Annotation of src/usr.bin/ssh/channels.c, Revision 1.296
1.296 ! andreas 1: /* $OpenBSD: channels.c,v 1.295 2009/02/12 03:00:56 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>
1.234 stevesk 43: #include <sys/ioctl.h>
1.235 stevesk 44: #include <sys/un.h>
1.251 stevesk 45: #include <sys/socket.h>
1.261 stevesk 46: #include <sys/time.h>
1.275 djm 47: #include <sys/queue.h>
1.251 stevesk 48:
49: #include <netinet/in.h>
50: #include <arpa/inet.h>
1.233 stevesk 51:
1.254 stevesk 52: #include <errno.h>
1.255 stevesk 53: #include <netdb.h>
1.263 stevesk 54: #include <stdio.h>
1.262 stevesk 55: #include <stdlib.h>
1.260 stevesk 56: #include <string.h>
1.233 stevesk 57: #include <termios.h>
1.256 stevesk 58: #include <unistd.h>
1.265 deraadt 59: #include <stdarg.h>
1.1 deraadt 60:
1.265 deraadt 61: #include "xmalloc.h"
1.1 deraadt 62: #include "ssh.h"
1.82 markus 63: #include "ssh1.h"
64: #include "ssh2.h"
1.1 deraadt 65: #include "packet.h"
1.82 markus 66: #include "log.h"
67: #include "misc.h"
1.265 deraadt 68: #include "buffer.h"
1.14 markus 69: #include "channels.h"
70: #include "compat.h"
1.82 markus 71: #include "canohost.h"
1.64 markus 72: #include "key.h"
73: #include "authfd.h"
1.147 stevesk 74: #include "pathnames.h"
1.1 deraadt 75:
1.121 markus 76: /* -- channel core */
1.12 markus 77:
1.27 markus 78: /*
79: * Pointer to an array containing all allocated channels. The array is
80: * dynamically extended as needed.
81: */
1.113 markus 82: static Channel **channels = NULL;
1.1 deraadt 83:
1.27 markus 84: /*
85: * Size of the channel array. All slots of the array must always be
1.113 markus 86: * initialized (at least the type field); unused slots set to NULL
1.27 markus 87: */
1.209 avsm 88: static u_int channels_alloc = 0;
1.1 deraadt 89:
1.27 markus 90: /*
91: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 92: * updated in channel_new.
1.27 markus 93: */
1.84 markus 94: static int channel_max_fd = 0;
1.1 deraadt 95:
96:
1.121 markus 97: /* -- tcp forwarding */
1.1 deraadt 98:
1.27 markus 99: /*
100: * Data structure for storing which hosts are permitted for forward requests.
101: * The local sides of any remote forwards are stored in this array to prevent
102: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
103: * network (which might be behind a firewall).
104: */
1.25 markus 105: typedef struct {
1.41 markus 106: char *host_to_connect; /* Connect to 'host'. */
107: u_short port_to_connect; /* Connect to 'port'. */
108: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 109: } ForwardPermission;
110:
1.257 dtucker 111: /* List of all permitted host/port pairs to connect by the user. */
1.1 deraadt 112: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 113:
1.257 dtucker 114: /* List of all permitted host/port pairs to connect by the admin. */
115: static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
116:
117: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 118: static int num_permitted_opens = 0;
1.257 dtucker 119:
120: /* Number of permitted host/port pair in the array permitted by the admin. */
121: static int num_adm_permitted_opens = 0;
122:
1.27 markus 123: /*
124: * If this is true, all opens are permitted. This is the case on the server
125: * on which we have to trust the client anyway, and the user could do
126: * anything after logging in anyway.
127: */
1.1 deraadt 128: static int all_opens_permitted = 0;
129:
1.121 markus 130:
131: /* -- X11 forwarding */
132:
133: /* Maximum number of fake X11 displays to try. */
134: #define MAX_DISPLAYS 1000
135:
1.219 djm 136: /* Saved X11 local (client) display. */
137: static char *x11_saved_display = NULL;
138:
1.121 markus 139: /* Saved X11 authentication protocol name. */
140: static char *x11_saved_proto = NULL;
141:
142: /* Saved X11 authentication data. This is the real data. */
143: static char *x11_saved_data = NULL;
144: static u_int x11_saved_data_len = 0;
145:
146: /*
147: * Fake X11 authentication data. This is what the server will be sending us;
148: * we should replace any occurrences of this by the real data.
149: */
1.240 deraadt 150: static u_char *x11_fake_data = NULL;
1.121 markus 151: static u_int x11_fake_data_len;
152:
153:
154: /* -- agent forwarding */
155:
156: #define NUM_SOCKS 10
157:
1.82 markus 158: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 159: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 160:
1.121 markus 161: /* helper */
1.127 itojun 162: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 163:
1.276 djm 164: /* non-blocking connect helpers */
165: static int connect_next(struct channel_connect *);
166: static void channel_connect_ctx_free(struct channel_connect *);
167:
1.121 markus 168: /* -- channel core */
1.41 markus 169:
170: Channel *
1.229 markus 171: channel_by_id(int id)
1.41 markus 172: {
173: Channel *c;
1.113 markus 174:
1.209 avsm 175: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 176: logit("channel_by_id: %d: bad id", id);
1.41 markus 177: return NULL;
178: }
1.113 markus 179: c = channels[id];
180: if (c == NULL) {
1.229 markus 181: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 182: return NULL;
183: }
184: return c;
1.55 markus 185: }
186:
1.27 markus 187: /*
1.229 markus 188: * Returns the channel if it is allowed to receive protocol messages.
189: * Private channels, like listening sockets, may not receive messages.
190: */
191: Channel *
192: channel_lookup(int id)
193: {
194: Channel *c;
195:
196: if ((c = channel_by_id(id)) == NULL)
197: return (NULL);
198:
1.237 deraadt 199: switch (c->type) {
1.229 markus 200: case SSH_CHANNEL_X11_OPEN:
201: case SSH_CHANNEL_LARVAL:
202: case SSH_CHANNEL_CONNECTING:
203: case SSH_CHANNEL_DYNAMIC:
204: case SSH_CHANNEL_OPENING:
205: case SSH_CHANNEL_OPEN:
206: case SSH_CHANNEL_INPUT_DRAINING:
207: case SSH_CHANNEL_OUTPUT_DRAINING:
208: return (c);
209: }
210: logit("Non-public channel %d, type %d.", id, c->type);
211: return (NULL);
212: }
213:
214: /*
1.55 markus 215: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 216: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 217: */
1.127 itojun 218: static void
1.71 markus 219: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 220: int extusage, int nonblock, int is_tty)
1.1 deraadt 221: {
1.25 markus 222: /* Update the maximum file descriptor value. */
1.84 markus 223: channel_max_fd = MAX(channel_max_fd, rfd);
224: channel_max_fd = MAX(channel_max_fd, wfd);
225: channel_max_fd = MAX(channel_max_fd, efd);
226:
1.27 markus 227: /* XXX set close-on-exec -markus */
1.55 markus 228:
1.52 markus 229: c->rfd = rfd;
230: c->wfd = wfd;
231: c->sock = (rfd == wfd) ? rfd : -1;
1.204 djm 232: c->ctl_fd = -1; /* XXX: set elsewhere */
1.52 markus 233: c->efd = efd;
234: c->extended_usage = extusage;
1.71 markus 235:
1.282 dtucker 236: if ((c->isatty = is_tty) != 0)
1.194 markus 237: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 238:
1.71 markus 239: /* enable nonblocking mode */
240: if (nonblock) {
241: if (rfd != -1)
242: set_nonblock(rfd);
243: if (wfd != -1)
244: set_nonblock(wfd);
245: if (efd != -1)
246: set_nonblock(efd);
247: }
1.52 markus 248: }
249:
250: /*
251: * Allocate a new channel object and set its type and socket. This will cause
252: * remote_name to be freed.
253: */
1.113 markus 254: Channel *
1.52 markus 255: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 256: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 257: {
1.209 avsm 258: int found;
259: u_int i;
1.52 markus 260: Channel *c;
1.25 markus 261:
262: /* Do initial allocation if this is the first call. */
263: if (channels_alloc == 0) {
264: channels_alloc = 10;
1.242 djm 265: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 266: for (i = 0; i < channels_alloc; i++)
1.113 markus 267: channels[i] = NULL;
1.25 markus 268: }
269: /* Try to find a free slot where to put the new channel. */
270: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 271: if (channels[i] == NULL) {
1.25 markus 272: /* Found a free slot. */
1.209 avsm 273: found = (int)i;
1.25 markus 274: break;
275: }
1.209 avsm 276: if (found < 0) {
1.27 markus 277: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 278: found = channels_alloc;
1.179 markus 279: if (channels_alloc > 10000)
280: fatal("channel_new: internal error: channels_alloc %d "
281: "too big.", channels_alloc);
1.243 djm 282: channels = xrealloc(channels, channels_alloc + 10,
283: sizeof(Channel *));
1.195 markus 284: channels_alloc += 10;
1.70 markus 285: debug2("channel: expanding %d", channels_alloc);
1.25 markus 286: for (i = found; i < channels_alloc; i++)
1.113 markus 287: channels[i] = NULL;
1.25 markus 288: }
1.113 markus 289: /* Initialize and return new channel. */
1.242 djm 290: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 291: buffer_init(&c->input);
292: buffer_init(&c->output);
1.41 markus 293: buffer_init(&c->extended);
1.293 djm 294: c->path = NULL;
1.159 markus 295: c->ostate = CHAN_OUTPUT_OPEN;
296: c->istate = CHAN_INPUT_OPEN;
297: c->flags = 0;
1.281 djm 298: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 299: c->self = found;
300: c->type = type;
1.41 markus 301: c->ctype = ctype;
1.51 markus 302: c->local_window = window;
303: c->local_window_max = window;
304: c->local_consumed = 0;
305: c->local_maxpacket = maxpack;
1.25 markus 306: c->remote_id = -1;
1.190 markus 307: c->remote_name = xstrdup(remote_name);
1.41 markus 308: c->remote_window = 0;
309: c->remote_maxpacket = 0;
1.133 markus 310: c->force_drain = 0;
1.149 markus 311: c->single_connection = 0;
1.131 markus 312: c->detach_user = NULL;
1.225 djm 313: c->detach_close = 0;
1.275 djm 314: c->open_confirm = NULL;
315: c->open_confirm_ctx = NULL;
1.65 markus 316: c->input_filter = NULL;
1.231 reyk 317: c->output_filter = NULL;
1.280 djm 318: c->filter_ctx = NULL;
319: c->filter_cleanup = NULL;
1.275 djm 320: TAILQ_INIT(&c->status_confirms);
1.25 markus 321: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 322: return c;
1.1 deraadt 323: }
1.52 markus 324:
1.132 markus 325: static int
326: channel_find_maxfd(void)
327: {
1.209 avsm 328: u_int i;
329: int max = 0;
1.132 markus 330: Channel *c;
331:
332: for (i = 0; i < channels_alloc; i++) {
333: c = channels[i];
334: if (c != NULL) {
335: max = MAX(max, c->rfd);
336: max = MAX(max, c->wfd);
337: max = MAX(max, c->efd);
338: }
339: }
340: return max;
341: }
342:
343: int
344: channel_close_fd(int *fdp)
345: {
346: int ret = 0, fd = *fdp;
347:
348: if (fd != -1) {
349: ret = close(fd);
350: *fdp = -1;
351: if (fd == channel_max_fd)
352: channel_max_fd = channel_find_maxfd();
353: }
354: return ret;
355: }
356:
1.52 markus 357: /* Close all channel fd/socket. */
1.127 itojun 358: static void
1.52 markus 359: channel_close_fds(Channel *c)
360: {
1.204 djm 361: debug3("channel %d: close_fds r %d w %d e %d c %d",
362: c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
1.118 markus 363:
1.132 markus 364: channel_close_fd(&c->sock);
1.204 djm 365: channel_close_fd(&c->ctl_fd);
1.132 markus 366: channel_close_fd(&c->rfd);
367: channel_close_fd(&c->wfd);
368: channel_close_fd(&c->efd);
1.121 markus 369: }
370:
371: /* Free the channel and close its fd/socket. */
372: void
373: channel_free(Channel *c)
374: {
375: char *s;
1.209 avsm 376: u_int i, n;
1.275 djm 377: struct channel_confirm *cc;
1.121 markus 378:
379: for (n = 0, i = 0; i < channels_alloc; i++)
380: if (channels[i])
381: n++;
1.209 avsm 382: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 383: c->remote_name ? c->remote_name : "???", n);
384:
385: s = channel_open_message();
1.194 markus 386: debug3("channel %d: status: %s", c->self, s);
1.121 markus 387: xfree(s);
388:
389: if (c->sock != -1)
390: shutdown(c->sock, SHUT_RDWR);
1.204 djm 391: if (c->ctl_fd != -1)
392: shutdown(c->ctl_fd, SHUT_RDWR);
1.121 markus 393: channel_close_fds(c);
394: buffer_free(&c->input);
395: buffer_free(&c->output);
396: buffer_free(&c->extended);
397: if (c->remote_name) {
398: xfree(c->remote_name);
399: c->remote_name = NULL;
400: }
1.293 djm 401: if (c->path) {
402: xfree(c->path);
403: c->path = NULL;
404: }
1.275 djm 405: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
406: if (cc->abandon_cb != NULL)
407: cc->abandon_cb(c, cc->ctx);
408: TAILQ_REMOVE(&c->status_confirms, cc, entry);
409: bzero(cc, sizeof(*cc));
410: xfree(cc);
411: }
1.280 djm 412: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
413: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 414: channels[c->self] = NULL;
415: xfree(c);
416: }
417:
418: void
1.126 markus 419: channel_free_all(void)
1.121 markus 420: {
1.209 avsm 421: u_int i;
1.121 markus 422:
1.126 markus 423: for (i = 0; i < channels_alloc; i++)
424: if (channels[i] != NULL)
425: channel_free(channels[i]);
1.131 markus 426: }
427:
1.121 markus 428: /*
429: * Closes the sockets/fds of all channels. This is used to close extra file
430: * descriptors after a fork.
431: */
432: void
1.142 itojun 433: channel_close_all(void)
1.121 markus 434: {
1.209 avsm 435: u_int i;
1.121 markus 436:
437: for (i = 0; i < channels_alloc; i++)
438: if (channels[i] != NULL)
439: channel_close_fds(channels[i]);
440: }
441:
442: /*
1.131 markus 443: * Stop listening to channels.
444: */
445: void
446: channel_stop_listening(void)
447: {
1.209 avsm 448: u_int i;
1.131 markus 449: Channel *c;
450:
451: for (i = 0; i < channels_alloc; i++) {
452: c = channels[i];
453: if (c != NULL) {
454: switch (c->type) {
455: case SSH_CHANNEL_AUTH_SOCKET:
456: case SSH_CHANNEL_PORT_LISTENER:
457: case SSH_CHANNEL_RPORT_LISTENER:
458: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 459: channel_close_fd(&c->sock);
1.131 markus 460: channel_free(c);
461: break;
462: }
463: }
464: }
465: }
466:
467: /*
1.121 markus 468: * Returns true if no channel has too much buffered data, and false if one or
469: * more channel is overfull.
470: */
471: int
1.142 itojun 472: channel_not_very_much_buffered_data(void)
1.121 markus 473: {
474: u_int i;
475: Channel *c;
476:
477: for (i = 0; i < channels_alloc; i++) {
478: c = channels[i];
479: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 480: #if 0
481: if (!compat20 &&
482: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 483: debug2("channel %d: big input buffer %d",
1.121 markus 484: c->self, buffer_len(&c->input));
485: return 0;
486: }
1.136 markus 487: #endif
1.121 markus 488: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 489: debug2("channel %d: big output buffer %u > %u",
1.136 markus 490: c->self, buffer_len(&c->output),
491: packet_get_maxsize());
1.121 markus 492: return 0;
493: }
494: }
495: }
496: return 1;
497: }
498:
499: /* Returns true if any channel is still open. */
500: int
1.142 itojun 501: channel_still_open(void)
1.121 markus 502: {
1.209 avsm 503: u_int i;
1.121 markus 504: Channel *c;
505:
506: for (i = 0; i < channels_alloc; i++) {
507: c = channels[i];
508: if (c == NULL)
509: continue;
510: switch (c->type) {
511: case SSH_CHANNEL_X11_LISTENER:
512: case SSH_CHANNEL_PORT_LISTENER:
513: case SSH_CHANNEL_RPORT_LISTENER:
514: case SSH_CHANNEL_CLOSED:
515: case SSH_CHANNEL_AUTH_SOCKET:
516: case SSH_CHANNEL_DYNAMIC:
517: case SSH_CHANNEL_CONNECTING:
518: case SSH_CHANNEL_ZOMBIE:
519: continue;
520: case SSH_CHANNEL_LARVAL:
521: if (!compat20)
522: fatal("cannot happen: SSH_CHANNEL_LARVAL");
523: continue;
524: case SSH_CHANNEL_OPENING:
525: case SSH_CHANNEL_OPEN:
526: case SSH_CHANNEL_X11_OPEN:
527: return 1;
528: case SSH_CHANNEL_INPUT_DRAINING:
529: case SSH_CHANNEL_OUTPUT_DRAINING:
530: if (!compat13)
531: fatal("cannot happen: OUT_DRAIN");
532: return 1;
533: default:
534: fatal("channel_still_open: bad channel type %d", c->type);
535: /* NOTREACHED */
536: }
537: }
538: return 0;
539: }
540:
541: /* Returns the id of an open channel suitable for keepaliving */
542: int
1.142 itojun 543: channel_find_open(void)
1.121 markus 544: {
1.209 avsm 545: u_int i;
1.121 markus 546: Channel *c;
547:
548: for (i = 0; i < channels_alloc; i++) {
549: c = channels[i];
1.206 djm 550: if (c == NULL || c->remote_id < 0)
1.121 markus 551: continue;
552: switch (c->type) {
553: case SSH_CHANNEL_CLOSED:
554: case SSH_CHANNEL_DYNAMIC:
555: case SSH_CHANNEL_X11_LISTENER:
556: case SSH_CHANNEL_PORT_LISTENER:
557: case SSH_CHANNEL_RPORT_LISTENER:
558: case SSH_CHANNEL_OPENING:
559: case SSH_CHANNEL_CONNECTING:
560: case SSH_CHANNEL_ZOMBIE:
561: continue;
562: case SSH_CHANNEL_LARVAL:
563: case SSH_CHANNEL_AUTH_SOCKET:
564: case SSH_CHANNEL_OPEN:
565: case SSH_CHANNEL_X11_OPEN:
566: return i;
567: case SSH_CHANNEL_INPUT_DRAINING:
568: case SSH_CHANNEL_OUTPUT_DRAINING:
569: if (!compat13)
570: fatal("cannot happen: OUT_DRAIN");
571: return i;
572: default:
573: fatal("channel_find_open: bad channel type %d", c->type);
574: /* NOTREACHED */
575: }
576: }
577: return -1;
578: }
579:
580:
581: /*
582: * Returns a message describing the currently open forwarded connections,
583: * suitable for sending to the client. The message contains crlf pairs for
584: * newlines.
585: */
586: char *
1.142 itojun 587: channel_open_message(void)
1.121 markus 588: {
589: Buffer buffer;
590: Channel *c;
591: char buf[1024], *cp;
1.209 avsm 592: u_int i;
1.121 markus 593:
594: buffer_init(&buffer);
595: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
596: buffer_append(&buffer, buf, strlen(buf));
597: for (i = 0; i < channels_alloc; i++) {
598: c = channels[i];
599: if (c == NULL)
600: continue;
601: switch (c->type) {
602: case SSH_CHANNEL_X11_LISTENER:
603: case SSH_CHANNEL_PORT_LISTENER:
604: case SSH_CHANNEL_RPORT_LISTENER:
605: case SSH_CHANNEL_CLOSED:
606: case SSH_CHANNEL_AUTH_SOCKET:
607: case SSH_CHANNEL_ZOMBIE:
608: continue;
609: case SSH_CHANNEL_LARVAL:
610: case SSH_CHANNEL_OPENING:
611: case SSH_CHANNEL_CONNECTING:
612: case SSH_CHANNEL_DYNAMIC:
613: case SSH_CHANNEL_OPEN:
614: case SSH_CHANNEL_X11_OPEN:
615: case SSH_CHANNEL_INPUT_DRAINING:
616: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 617: snprintf(buf, sizeof buf,
618: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
1.121 markus 619: c->self, c->remote_name,
620: c->type, c->remote_id,
621: c->istate, buffer_len(&c->input),
622: c->ostate, buffer_len(&c->output),
1.204 djm 623: c->rfd, c->wfd, c->ctl_fd);
1.121 markus 624: buffer_append(&buffer, buf, strlen(buf));
625: continue;
626: default:
627: fatal("channel_open_message: bad channel type %d", c->type);
628: /* NOTREACHED */
629: }
630: }
631: buffer_append(&buffer, "\0", 1);
632: cp = xstrdup(buffer_ptr(&buffer));
633: buffer_free(&buffer);
634: return cp;
635: }
636:
637: void
638: channel_send_open(int id)
639: {
640: Channel *c = channel_lookup(id);
1.180 deraadt 641:
1.121 markus 642: if (c == NULL) {
1.188 itojun 643: logit("channel_send_open: %d: bad id", id);
1.121 markus 644: return;
645: }
1.184 markus 646: debug2("channel %d: send open", id);
1.121 markus 647: packet_start(SSH2_MSG_CHANNEL_OPEN);
648: packet_put_cstring(c->ctype);
649: packet_put_int(c->self);
650: packet_put_int(c->local_window);
651: packet_put_int(c->local_maxpacket);
652: packet_send();
653: }
654:
655: void
1.184 markus 656: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 657: {
1.184 markus 658: Channel *c = channel_lookup(id);
1.180 deraadt 659:
1.121 markus 660: if (c == NULL) {
1.188 itojun 661: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 662: return;
663: }
1.204 djm 664: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 665: packet_start(SSH2_MSG_CHANNEL_REQUEST);
666: packet_put_int(c->remote_id);
667: packet_put_cstring(service);
668: packet_put_char(wantconfirm);
669: }
1.241 deraadt 670:
1.121 markus 671: void
1.275 djm 672: channel_register_status_confirm(int id, channel_confirm_cb *cb,
673: channel_confirm_abandon_cb *abandon_cb, void *ctx)
674: {
675: struct channel_confirm *cc;
676: Channel *c;
677:
678: if ((c = channel_lookup(id)) == NULL)
679: fatal("channel_register_expect: %d: bad id", id);
680:
681: cc = xmalloc(sizeof(*cc));
682: cc->cb = cb;
683: cc->abandon_cb = abandon_cb;
684: cc->ctx = ctx;
685: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
686: }
687:
688: void
689: channel_register_open_confirm(int id, channel_callback_fn *fn, void *ctx)
1.121 markus 690: {
691: Channel *c = channel_lookup(id);
1.180 deraadt 692:
1.121 markus 693: if (c == NULL) {
1.287 stevesk 694: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 695: return;
696: }
1.275 djm 697: c->open_confirm = fn;
698: c->open_confirm_ctx = ctx;
1.121 markus 699: }
1.241 deraadt 700:
1.121 markus 701: void
1.225 djm 702: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 703: {
1.229 markus 704: Channel *c = channel_by_id(id);
1.180 deraadt 705:
1.121 markus 706: if (c == NULL) {
1.188 itojun 707: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 708: return;
709: }
1.131 markus 710: c->detach_user = fn;
1.225 djm 711: c->detach_close = do_close;
1.121 markus 712: }
1.241 deraadt 713:
1.121 markus 714: void
715: channel_cancel_cleanup(int id)
716: {
1.229 markus 717: Channel *c = channel_by_id(id);
1.180 deraadt 718:
1.121 markus 719: if (c == NULL) {
1.188 itojun 720: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 721: return;
1.52 markus 722: }
1.131 markus 723: c->detach_user = NULL;
1.225 djm 724: c->detach_close = 0;
1.121 markus 725: }
1.241 deraadt 726:
1.121 markus 727: void
1.231 reyk 728: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 729: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 730: {
731: Channel *c = channel_lookup(id);
1.180 deraadt 732:
1.121 markus 733: if (c == NULL) {
1.188 itojun 734: logit("channel_register_filter: %d: bad id", id);
1.121 markus 735: return;
1.52 markus 736: }
1.231 reyk 737: c->input_filter = ifn;
738: c->output_filter = ofn;
1.279 djm 739: c->filter_ctx = ctx;
1.280 djm 740: c->filter_cleanup = cfn;
1.52 markus 741: }
742:
1.49 markus 743: void
1.121 markus 744: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 745: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 746: {
1.121 markus 747: Channel *c = channel_lookup(id);
1.180 deraadt 748:
1.121 markus 749: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
750: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 751: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 752: c->type = SSH_CHANNEL_OPEN;
1.168 markus 753: c->local_window = c->local_window_max = window_max;
1.121 markus 754: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
755: packet_put_int(c->remote_id);
756: packet_put_int(c->local_window);
757: packet_send();
1.1 deraadt 758: }
759:
1.27 markus 760: /*
1.41 markus 761: * 'channel_pre*' are called just before select() to add any bits relevant to
762: * channels in the select bitmasks.
763: */
764: /*
765: * 'channel_post*': perform any appropriate operations for channels which
766: * have events pending.
1.27 markus 767: */
1.237 deraadt 768: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 769: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
770: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
771:
1.259 stevesk 772: /* ARGSUSED */
1.127 itojun 773: static void
1.237 deraadt 774: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 775: {
776: FD_SET(c->sock, readset);
777: }
778:
1.259 stevesk 779: /* ARGSUSED */
1.127 itojun 780: static void
1.237 deraadt 781: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 782: {
783: debug3("channel %d: waiting for connection", c->self);
784: FD_SET(c->sock, writeset);
785: }
786:
1.127 itojun 787: static void
1.237 deraadt 788: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 789: {
790: if (buffer_len(&c->input) < packet_get_maxsize())
791: FD_SET(c->sock, readset);
792: if (buffer_len(&c->output) > 0)
793: FD_SET(c->sock, writeset);
794: }
1.1 deraadt 795:
1.127 itojun 796: static void
1.237 deraadt 797: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 798: {
1.157 markus 799: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 800:
1.44 markus 801: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 802: limit > 0 &&
1.250 djm 803: buffer_len(&c->input) < limit &&
804: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 805: FD_SET(c->rfd, readset);
806: if (c->ostate == CHAN_OUTPUT_OPEN ||
807: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
808: if (buffer_len(&c->output) > 0) {
809: FD_SET(c->wfd, writeset);
810: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 811: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 812: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
813: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 814: else
815: chan_obuf_empty(c);
1.44 markus 816: }
817: }
818: /** XXX check close conditions, too */
1.277 markus 819: if (compat20 && c->efd != -1 &&
820: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 821: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
822: buffer_len(&c->extended) > 0)
823: FD_SET(c->efd, writeset);
1.172 markus 824: else if (!(c->flags & CHAN_EOF_SENT) &&
825: c->extended_usage == CHAN_EXTENDED_READ &&
1.44 markus 826: buffer_len(&c->extended) < c->remote_window)
827: FD_SET(c->efd, readset);
828: }
1.204 djm 829: /* XXX: What about efd? races? */
1.208 deraadt 830: if (compat20 && c->ctl_fd != -1 &&
1.204 djm 831: c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
832: FD_SET(c->ctl_fd, readset);
1.44 markus 833: }
834:
1.259 stevesk 835: /* ARGSUSED */
1.127 itojun 836: static void
1.237 deraadt 837: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 838: {
839: if (buffer_len(&c->input) == 0) {
840: packet_start(SSH_MSG_CHANNEL_CLOSE);
841: packet_put_int(c->remote_id);
842: packet_send();
843: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 844: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 845: }
846: }
847:
1.259 stevesk 848: /* ARGSUSED */
1.127 itojun 849: static void
1.237 deraadt 850: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 851: {
852: if (buffer_len(&c->output) == 0)
1.113 markus 853: chan_mark_dead(c);
1.49 markus 854: else
1.41 markus 855: FD_SET(c->sock, writeset);
856: }
857:
858: /*
859: * This is a special state for X11 authentication spoofing. An opened X11
860: * connection (when authentication spoofing is being done) remains in this
861: * state until the first packet has been completely read. The authentication
862: * data in that packet is then substituted by the real data if it matches the
863: * fake data, and the channel is put into normal mode.
1.51 markus 864: * XXX All this happens at the client side.
1.121 markus 865: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 866: */
1.127 itojun 867: static int
1.121 markus 868: x11_open_helper(Buffer *b)
1.1 deraadt 869: {
1.77 markus 870: u_char *ucp;
871: u_int proto_len, data_len;
1.25 markus 872:
1.41 markus 873: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 874: if (buffer_len(b) < 12)
1.41 markus 875: return 0;
876:
877: /* Parse the lengths of variable-length fields. */
1.155 stevesk 878: ucp = buffer_ptr(b);
1.41 markus 879: if (ucp[0] == 0x42) { /* Byte order MSB first. */
880: proto_len = 256 * ucp[6] + ucp[7];
881: data_len = 256 * ucp[8] + ucp[9];
882: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
883: proto_len = ucp[6] + 256 * ucp[7];
884: data_len = ucp[8] + 256 * ucp[9];
885: } else {
1.194 markus 886: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 887: ucp[0]);
1.41 markus 888: return -1;
889: }
890:
891: /* Check if the whole packet is in buffer. */
1.121 markus 892: if (buffer_len(b) <
1.41 markus 893: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
894: return 0;
895:
896: /* Check if authentication protocol matches. */
897: if (proto_len != strlen(x11_saved_proto) ||
898: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 899: debug2("X11 connection uses different authentication protocol.");
1.41 markus 900: return -1;
901: }
902: /* Check if authentication data matches our fake data. */
903: if (data_len != x11_fake_data_len ||
904: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
905: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 906: debug2("X11 auth data does not match fake data.");
1.41 markus 907: return -1;
908: }
909: /* Check fake data length */
910: if (x11_fake_data_len != x11_saved_data_len) {
911: error("X11 fake_data_len %d != saved_data_len %d",
912: x11_fake_data_len, x11_saved_data_len);
913: return -1;
914: }
915: /*
916: * Received authentication protocol and data match
917: * our fake data. Substitute the fake data with real
918: * data.
919: */
920: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
921: x11_saved_data, x11_saved_data_len);
922: return 1;
923: }
924:
1.127 itojun 925: static void
1.237 deraadt 926: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 927: {
1.121 markus 928: int ret = x11_open_helper(&c->output);
1.180 deraadt 929:
1.41 markus 930: if (ret == 1) {
931: /* Start normal processing for the channel. */
932: c->type = SSH_CHANNEL_OPEN;
1.47 markus 933: channel_pre_open_13(c, readset, writeset);
1.41 markus 934: } else if (ret == -1) {
935: /*
936: * We have received an X11 connection that has bad
937: * authentication information.
938: */
1.188 itojun 939: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 940: buffer_clear(&c->input);
941: buffer_clear(&c->output);
1.132 markus 942: channel_close_fd(&c->sock);
1.41 markus 943: c->sock = -1;
944: c->type = SSH_CHANNEL_CLOSED;
945: packet_start(SSH_MSG_CHANNEL_CLOSE);
946: packet_put_int(c->remote_id);
947: packet_send();
948: }
949: }
1.25 markus 950:
1.127 itojun 951: static void
1.237 deraadt 952: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 953: {
1.121 markus 954: int ret = x11_open_helper(&c->output);
1.133 markus 955:
956: /* c->force_drain = 1; */
957:
1.41 markus 958: if (ret == 1) {
959: c->type = SSH_CHANNEL_OPEN;
1.157 markus 960: channel_pre_open(c, readset, writeset);
1.41 markus 961: } else if (ret == -1) {
1.188 itojun 962: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 963: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 964: chan_read_failed(c);
965: buffer_clear(&c->input);
966: chan_ibuf_empty(c);
967: buffer_clear(&c->output);
968: /* for proto v1, the peer will send an IEOF */
969: if (compat20)
970: chan_write_failed(c);
971: else
972: c->type = SSH_CHANNEL_OPEN;
1.194 markus 973: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 974: }
975: }
1.25 markus 976:
1.104 markus 977: /* try to decode a socks4 header */
1.259 stevesk 978: /* ARGSUSED */
1.127 itojun 979: static int
1.237 deraadt 980: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 981: {
1.181 markus 982: char *p, *host;
1.292 djm 983: u_int len, have, i, found, need;
1.148 deraadt 984: char username[256];
1.103 markus 985: struct {
986: u_int8_t version;
987: u_int8_t command;
988: u_int16_t dest_port;
1.104 markus 989: struct in_addr dest_addr;
1.103 markus 990: } s4_req, s4_rsp;
991:
1.104 markus 992: debug2("channel %d: decode socks4", c->self);
1.109 markus 993:
994: have = buffer_len(&c->input);
995: len = sizeof(s4_req);
996: if (have < len)
997: return 0;
998: p = buffer_ptr(&c->input);
1.292 djm 999:
1000: need = 1;
1001: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1002: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1003: debug2("channel %d: socks4a request", c->self);
1004: /* ... and needs an extra string (the hostname) */
1005: need = 2;
1006: }
1007: /* Check for terminating NUL on the string(s) */
1.109 markus 1008: for (found = 0, i = len; i < have; i++) {
1009: if (p[i] == '\0') {
1.292 djm 1010: found++;
1011: if (found == need)
1012: break;
1.109 markus 1013: }
1014: if (i > 1024) {
1015: /* the peer is probably sending garbage */
1016: debug("channel %d: decode socks4: too long",
1017: c->self);
1018: return -1;
1019: }
1020: }
1.292 djm 1021: if (found < need)
1.109 markus 1022: return 0;
1.103 markus 1023: buffer_get(&c->input, (char *)&s4_req.version, 1);
1024: buffer_get(&c->input, (char *)&s4_req.command, 1);
1025: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1026: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1027: have = buffer_len(&c->input);
1.103 markus 1028: p = buffer_ptr(&c->input);
1029: len = strlen(p);
1.106 markus 1030: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1031: len++; /* trailing '\0' */
1.103 markus 1032: if (len > have)
1.104 markus 1033: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1034: c->self, len, have);
1035: strlcpy(username, p, sizeof(username));
1036: buffer_consume(&c->input, len);
1037:
1.293 djm 1038: if (c->path != NULL) {
1039: xfree(c->path);
1040: c->path = NULL;
1041: }
1.292 djm 1042: if (need == 1) { /* SOCKS4: one string */
1043: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1044: c->path = xstrdup(host);
1.292 djm 1045: } else { /* SOCKS4A: two strings */
1046: have = buffer_len(&c->input);
1047: p = buffer_ptr(&c->input);
1048: len = strlen(p);
1049: debug2("channel %d: decode socks4a: host %s/%d",
1050: c->self, p, len);
1051: len++; /* trailing '\0' */
1052: if (len > have)
1053: fatal("channel %d: decode socks4a: len %d > have %d",
1054: c->self, len, have);
1.293 djm 1055: if (len > NI_MAXHOST) {
1.292 djm 1056: error("channel %d: hostname \"%.100s\" too long",
1057: c->self, p);
1058: return -1;
1059: }
1.293 djm 1060: c->path = xstrdup(p);
1.292 djm 1061: buffer_consume(&c->input, len);
1062: }
1.103 markus 1063: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1064:
1.194 markus 1065: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1066: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1067:
1.104 markus 1068: if (s4_req.command != 1) {
1.292 djm 1069: debug("channel %d: cannot handle: %s cn %d",
1070: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1071: return -1;
1.103 markus 1072: }
1.104 markus 1073: s4_rsp.version = 0; /* vn: 0 for reply */
1074: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1075: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1076: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1077: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1078: return 1;
1079: }
1080:
1.193 markus 1081: /* try to decode a socks5 header */
1082: #define SSH_SOCKS5_AUTHDONE 0x1000
1083: #define SSH_SOCKS5_NOAUTH 0x00
1084: #define SSH_SOCKS5_IPV4 0x01
1085: #define SSH_SOCKS5_DOMAIN 0x03
1086: #define SSH_SOCKS5_IPV6 0x04
1087: #define SSH_SOCKS5_CONNECT 0x01
1088: #define SSH_SOCKS5_SUCCESS 0x00
1089:
1.259 stevesk 1090: /* ARGSUSED */
1.193 markus 1091: static int
1.237 deraadt 1092: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1093: {
1094: struct {
1095: u_int8_t version;
1096: u_int8_t command;
1097: u_int8_t reserved;
1098: u_int8_t atyp;
1099: } s5_req, s5_rsp;
1100: u_int16_t dest_port;
1.293 djm 1101: u_char *p, dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.252 djm 1102: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1103:
1104: debug2("channel %d: decode socks5", c->self);
1105: p = buffer_ptr(&c->input);
1106: if (p[0] != 0x05)
1107: return -1;
1108: have = buffer_len(&c->input);
1109: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1110: /* format: ver | nmethods | methods */
1.198 djm 1111: if (have < 2)
1.193 markus 1112: return 0;
1113: nmethods = p[1];
1114: if (have < nmethods + 2)
1115: return 0;
1116: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1117: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1118: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1119: found = 1;
1120: break;
1121: }
1122: }
1123: if (!found) {
1124: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1125: c->self);
1126: return -1;
1127: }
1128: buffer_consume(&c->input, nmethods + 2);
1129: buffer_put_char(&c->output, 0x05); /* version */
1130: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1131: FD_SET(c->sock, writeset);
1132: c->flags |= SSH_SOCKS5_AUTHDONE;
1133: debug2("channel %d: socks5 auth done", c->self);
1134: return 0; /* need more */
1135: }
1136: debug2("channel %d: socks5 post auth", c->self);
1137: if (have < sizeof(s5_req)+1)
1138: return 0; /* need more */
1.247 deraadt 1139: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1140: if (s5_req.version != 0x05 ||
1141: s5_req.command != SSH_SOCKS5_CONNECT ||
1142: s5_req.reserved != 0x00) {
1.194 markus 1143: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1144: return -1;
1145: }
1.213 deraadt 1146: switch (s5_req.atyp){
1.193 markus 1147: case SSH_SOCKS5_IPV4:
1148: addrlen = 4;
1149: af = AF_INET;
1150: break;
1151: case SSH_SOCKS5_DOMAIN:
1152: addrlen = p[sizeof(s5_req)];
1153: af = -1;
1154: break;
1155: case SSH_SOCKS5_IPV6:
1156: addrlen = 16;
1157: af = AF_INET6;
1158: break;
1159: default:
1.194 markus 1160: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1161: return -1;
1162: }
1.252 djm 1163: need = sizeof(s5_req) + addrlen + 2;
1164: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1165: need++;
1166: if (have < need)
1.193 markus 1167: return 0;
1168: buffer_consume(&c->input, sizeof(s5_req));
1169: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1170: buffer_consume(&c->input, 1); /* host string length */
1171: buffer_get(&c->input, (char *)&dest_addr, addrlen);
1172: buffer_get(&c->input, (char *)&dest_port, 2);
1173: dest_addr[addrlen] = '\0';
1.293 djm 1174: if (c->path != NULL) {
1175: xfree(c->path);
1176: c->path = NULL;
1177: }
1178: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1179: if (addrlen >= NI_MAXHOST) {
1.293 djm 1180: error("channel %d: dynamic request: socks5 hostname "
1181: "\"%.100s\" too long", c->self, dest_addr);
1182: return -1;
1183: }
1184: c->path = xstrdup(dest_addr);
1185: } else {
1186: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1187: return -1;
1188: c->path = xstrdup(ntop);
1189: }
1.193 markus 1190: c->host_port = ntohs(dest_port);
1.198 djm 1191:
1.194 markus 1192: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1193: c->self, c->path, c->host_port, s5_req.command);
1194:
1195: s5_rsp.version = 0x05;
1196: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1197: s5_rsp.reserved = 0; /* ignored */
1198: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1199: ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1200: dest_port = 0; /* ignored */
1201:
1.246 deraadt 1202: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1203: buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1204: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1205: return 1;
1206: }
1207:
1.104 markus 1208: /* dynamic port forwarding */
1.127 itojun 1209: static void
1.237 deraadt 1210: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1211: {
1212: u_char *p;
1.217 djm 1213: u_int have;
1214: int ret;
1.103 markus 1215:
1.104 markus 1216: have = buffer_len(&c->input);
1.137 markus 1217: c->delayed = 0;
1.104 markus 1218: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1219: /* buffer_dump(&c->input); */
1.104 markus 1220: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1221: if (have < 3) {
1.104 markus 1222: /* need more */
1223: FD_SET(c->sock, readset);
1224: return;
1225: }
1226: /* try to guess the protocol */
1227: p = buffer_ptr(&c->input);
1228: switch (p[0]) {
1229: case 0x04:
1230: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1231: break;
1232: case 0x05:
1233: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1234: break;
1235: default:
1236: ret = -1;
1237: break;
1238: }
1239: if (ret < 0) {
1.113 markus 1240: chan_mark_dead(c);
1.104 markus 1241: } else if (ret == 0) {
1242: debug2("channel %d: pre_dynamic: need more", c->self);
1243: /* need more */
1244: FD_SET(c->sock, readset);
1245: } else {
1246: /* switch to the next state */
1247: c->type = SSH_CHANNEL_OPENING;
1248: port_open_helper(c, "direct-tcpip");
1249: }
1.103 markus 1250: }
1251:
1.41 markus 1252: /* This is our fake X11 server socket. */
1.259 stevesk 1253: /* ARGSUSED */
1.127 itojun 1254: static void
1.237 deraadt 1255: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1256: {
1.113 markus 1257: Channel *nc;
1.285 djm 1258: struct sockaddr_storage addr;
1.162 stevesk 1259: int newsock;
1.41 markus 1260: socklen_t addrlen;
1.85 markus 1261: char buf[16384], *remote_ipaddr;
1.51 markus 1262: int remote_port;
1.25 markus 1263:
1.41 markus 1264: if (FD_ISSET(c->sock, readset)) {
1265: debug("X11 connection requested.");
1266: addrlen = sizeof(addr);
1.285 djm 1267: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1268: if (c->single_connection) {
1.194 markus 1269: debug2("single_connection: closing X11 listener.");
1.149 markus 1270: channel_close_fd(&c->sock);
1271: chan_mark_dead(c);
1272: }
1.41 markus 1273: if (newsock < 0) {
1274: error("accept: %.100s", strerror(errno));
1275: return;
1276: }
1.162 stevesk 1277: set_nodelay(newsock);
1.85 markus 1278: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1279: remote_port = get_peer_port(newsock);
1.41 markus 1280: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1281: remote_ipaddr, remote_port);
1.51 markus 1282:
1.113 markus 1283: nc = channel_new("accepted x11 socket",
1.51 markus 1284: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1285: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1286: if (compat20) {
1287: packet_start(SSH2_MSG_CHANNEL_OPEN);
1288: packet_put_cstring("x11");
1.113 markus 1289: packet_put_int(nc->self);
1.149 markus 1290: packet_put_int(nc->local_window_max);
1291: packet_put_int(nc->local_maxpacket);
1.85 markus 1292: /* originator ipaddr and port */
1293: packet_put_cstring(remote_ipaddr);
1.57 markus 1294: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1295: debug2("ssh2 x11 bug compat mode");
1.57 markus 1296: } else {
1297: packet_put_int(remote_port);
1298: }
1.51 markus 1299: packet_send();
1300: } else {
1301: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1302: packet_put_int(nc->self);
1.121 markus 1303: if (packet_get_protocol_flags() &
1304: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1305: packet_put_cstring(buf);
1.51 markus 1306: packet_send();
1307: }
1.85 markus 1308: xfree(remote_ipaddr);
1.41 markus 1309: }
1310: }
1.25 markus 1311:
1.127 itojun 1312: static void
1.103 markus 1313: port_open_helper(Channel *c, char *rtype)
1314: {
1315: int direct;
1316: char buf[1024];
1317: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1318: int remote_port = get_peer_port(c->sock);
1.103 markus 1319:
1320: direct = (strcmp(rtype, "direct-tcpip") == 0);
1321:
1322: snprintf(buf, sizeof buf,
1323: "%s: listening port %d for %.100s port %d, "
1324: "connect from %.200s port %d",
1325: rtype, c->listening_port, c->path, c->host_port,
1326: remote_ipaddr, remote_port);
1327:
1328: xfree(c->remote_name);
1329: c->remote_name = xstrdup(buf);
1330:
1331: if (compat20) {
1332: packet_start(SSH2_MSG_CHANNEL_OPEN);
1333: packet_put_cstring(rtype);
1334: packet_put_int(c->self);
1335: packet_put_int(c->local_window_max);
1336: packet_put_int(c->local_maxpacket);
1337: if (direct) {
1338: /* target host, port */
1339: packet_put_cstring(c->path);
1340: packet_put_int(c->host_port);
1341: } else {
1342: /* listen address, port */
1343: packet_put_cstring(c->path);
1344: packet_put_int(c->listening_port);
1345: }
1346: /* originator host and port */
1347: packet_put_cstring(remote_ipaddr);
1.216 markus 1348: packet_put_int((u_int)remote_port);
1.103 markus 1349: packet_send();
1350: } else {
1351: packet_start(SSH_MSG_PORT_OPEN);
1352: packet_put_int(c->self);
1353: packet_put_cstring(c->path);
1354: packet_put_int(c->host_port);
1.121 markus 1355: if (packet_get_protocol_flags() &
1356: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1357: packet_put_cstring(c->remote_name);
1358: packet_send();
1359: }
1360: xfree(remote_ipaddr);
1361: }
1362:
1.226 djm 1363: static void
1364: channel_set_reuseaddr(int fd)
1365: {
1366: int on = 1;
1367:
1368: /*
1369: * Set socket options.
1370: * Allow local port reuse in TIME_WAIT.
1371: */
1372: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1373: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1374: }
1375:
1.41 markus 1376: /*
1377: * This socket is listening for connections to a forwarded TCP/IP port.
1378: */
1.259 stevesk 1379: /* ARGSUSED */
1.127 itojun 1380: static void
1.237 deraadt 1381: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1382: {
1.103 markus 1383: Channel *nc;
1.285 djm 1384: struct sockaddr_storage addr;
1.113 markus 1385: int newsock, nextstate;
1.41 markus 1386: socklen_t addrlen;
1.103 markus 1387: char *rtype;
1.73 markus 1388:
1.41 markus 1389: if (FD_ISSET(c->sock, readset)) {
1390: debug("Connection to port %d forwarding "
1391: "to %.100s port %d requested.",
1392: c->listening_port, c->path, c->host_port);
1.103 markus 1393:
1.137 markus 1394: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1395: nextstate = SSH_CHANNEL_OPENING;
1396: rtype = "forwarded-tcpip";
1397: } else {
1398: if (c->host_port == 0) {
1399: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1400: rtype = "dynamic-tcpip";
1.137 markus 1401: } else {
1402: nextstate = SSH_CHANNEL_OPENING;
1403: rtype = "direct-tcpip";
1404: }
1405: }
1.103 markus 1406:
1.41 markus 1407: addrlen = sizeof(addr);
1.285 djm 1408: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1409: if (newsock < 0) {
1410: error("accept: %.100s", strerror(errno));
1411: return;
1412: }
1.169 stevesk 1413: set_nodelay(newsock);
1.190 markus 1414: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1415: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1416: nc->listening_port = c->listening_port;
1417: nc->host_port = c->host_port;
1.293 djm 1418: if (c->path != NULL)
1419: nc->path = xstrdup(c->path);
1.103 markus 1420:
1.137 markus 1421: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1422: /*
1423: * do not call the channel_post handler until
1424: * this flag has been reset by a pre-handler.
1425: * otherwise the FD_ISSET calls might overflow
1426: */
1427: nc->delayed = 1;
1428: } else {
1.103 markus 1429: port_open_helper(nc, rtype);
1.137 markus 1430: }
1.41 markus 1431: }
1432: }
1.25 markus 1433:
1.41 markus 1434: /*
1435: * This is the authentication agent socket listening for connections from
1436: * clients.
1437: */
1.259 stevesk 1438: /* ARGSUSED */
1.127 itojun 1439: static void
1.237 deraadt 1440: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1441: {
1.113 markus 1442: Channel *nc;
1443: int newsock;
1.285 djm 1444: struct sockaddr_storage addr;
1.41 markus 1445: socklen_t addrlen;
1.25 markus 1446:
1.41 markus 1447: if (FD_ISSET(c->sock, readset)) {
1448: addrlen = sizeof(addr);
1.285 djm 1449: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1450: if (newsock < 0) {
1451: error("accept from auth socket: %.100s", strerror(errno));
1452: return;
1453: }
1.113 markus 1454: nc = channel_new("accepted auth socket",
1.73 markus 1455: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1456: c->local_window_max, c->local_maxpacket,
1.190 markus 1457: 0, "accepted auth socket", 1);
1.73 markus 1458: if (compat20) {
1459: packet_start(SSH2_MSG_CHANNEL_OPEN);
1460: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1461: packet_put_int(nc->self);
1.73 markus 1462: packet_put_int(c->local_window_max);
1463: packet_put_int(c->local_maxpacket);
1464: } else {
1465: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1466: packet_put_int(nc->self);
1.73 markus 1467: }
1.41 markus 1468: packet_send();
1469: }
1470: }
1.25 markus 1471:
1.259 stevesk 1472: /* ARGSUSED */
1.127 itojun 1473: static void
1.237 deraadt 1474: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1475: {
1.276 djm 1476: int err = 0, sock;
1.129 stevesk 1477: socklen_t sz = sizeof(err);
1.114 markus 1478:
1.75 markus 1479: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1480: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1481: err = errno;
1482: error("getsockopt SO_ERROR failed");
1483: }
1484: if (err == 0) {
1.276 djm 1485: debug("channel %d: connected to %s port %d",
1486: c->self, c->connect_ctx.host, c->connect_ctx.port);
1487: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1488: c->type = SSH_CHANNEL_OPEN;
1489: if (compat20) {
1490: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1491: packet_put_int(c->remote_id);
1492: packet_put_int(c->self);
1493: packet_put_int(c->local_window);
1494: packet_put_int(c->local_maxpacket);
1495: } else {
1496: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1497: packet_put_int(c->remote_id);
1498: packet_put_int(c->self);
1499: }
1.75 markus 1500: } else {
1.276 djm 1501: debug("channel %d: connection failed: %s",
1.114 markus 1502: c->self, strerror(err));
1.276 djm 1503: /* Try next address, if any */
1504: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1505: close(c->sock);
1506: c->sock = c->rfd = c->wfd = sock;
1507: channel_max_fd = channel_find_maxfd();
1508: return;
1509: }
1510: /* Exhausted all addresses */
1511: error("connect_to %.100s port %d: failed.",
1512: c->connect_ctx.host, c->connect_ctx.port);
1513: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1514: if (compat20) {
1515: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1516: packet_put_int(c->remote_id);
1517: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1518: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1519: packet_put_cstring(strerror(err));
1520: packet_put_cstring("");
1521: }
1.75 markus 1522: } else {
1.114 markus 1523: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1524: packet_put_int(c->remote_id);
1.75 markus 1525: }
1.114 markus 1526: chan_mark_dead(c);
1.75 markus 1527: }
1.114 markus 1528: packet_send();
1.75 markus 1529: }
1530: }
1531:
1.259 stevesk 1532: /* ARGSUSED */
1.127 itojun 1533: static int
1.237 deraadt 1534: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1535: {
1.214 markus 1536: char buf[CHAN_RBUF];
1.41 markus 1537: int len;
1.25 markus 1538:
1.118 markus 1539: if (c->rfd != -1 &&
1.41 markus 1540: FD_ISSET(c->rfd, readset)) {
1541: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1542: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1543: return 1;
1.41 markus 1544: if (len <= 0) {
1.194 markus 1545: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1546: c->self, c->rfd, len);
1.104 markus 1547: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1548: debug2("channel %d: not open", c->self);
1.113 markus 1549: chan_mark_dead(c);
1.103 markus 1550: return -1;
1.104 markus 1551: } else if (compat13) {
1.158 markus 1552: buffer_clear(&c->output);
1.41 markus 1553: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1554: debug2("channel %d: input draining.", c->self);
1.25 markus 1555: } else {
1.41 markus 1556: chan_read_failed(c);
1.25 markus 1557: }
1.41 markus 1558: return -1;
1559: }
1.143 deraadt 1560: if (c->input_filter != NULL) {
1.66 markus 1561: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1562: debug2("channel %d: filter stops", c->self);
1.65 markus 1563: chan_read_failed(c);
1564: }
1.228 reyk 1565: } else if (c->datagram) {
1566: buffer_put_string(&c->input, buf, len);
1.65 markus 1567: } else {
1568: buffer_append(&c->input, buf, len);
1569: }
1.41 markus 1570: }
1571: return 1;
1572: }
1.241 deraadt 1573:
1.259 stevesk 1574: /* ARGSUSED */
1.127 itojun 1575: static int
1.237 deraadt 1576: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1577: {
1.95 markus 1578: struct termios tio;
1.231 reyk 1579: u_char *data = NULL, *buf;
1.134 markus 1580: u_int dlen;
1.41 markus 1581: int len;
1.25 markus 1582:
1.41 markus 1583: /* Send buffered output data to the socket. */
1.118 markus 1584: if (c->wfd != -1 &&
1.41 markus 1585: FD_ISSET(c->wfd, writeset) &&
1586: buffer_len(&c->output) > 0) {
1.231 reyk 1587: if (c->output_filter != NULL) {
1588: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1589: debug2("channel %d: filter stops", c->self);
1.232 reyk 1590: if (c->type != SSH_CHANNEL_OPEN)
1591: chan_mark_dead(c);
1592: else
1593: chan_write_failed(c);
1594: return -1;
1.231 reyk 1595: }
1596: } else if (c->datagram) {
1597: buf = data = buffer_get_string(&c->output, &dlen);
1598: } else {
1599: buf = data = buffer_ptr(&c->output);
1600: dlen = buffer_len(&c->output);
1601: }
1602:
1.228 reyk 1603: if (c->datagram) {
1604: /* ignore truncated writes, datagrams might get lost */
1605: c->local_consumed += dlen + 4;
1.231 reyk 1606: len = write(c->wfd, buf, dlen);
1.228 reyk 1607: xfree(data);
1608: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1609: return 1;
1610: if (len <= 0) {
1611: if (c->type != SSH_CHANNEL_OPEN)
1612: chan_mark_dead(c);
1613: else
1614: chan_write_failed(c);
1615: return -1;
1616: }
1617: return 1;
1618: }
1.231 reyk 1619:
1620: len = write(c->wfd, buf, dlen);
1.53 markus 1621: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1622: return 1;
1.41 markus 1623: if (len <= 0) {
1.104 markus 1624: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1625: debug2("channel %d: not open", c->self);
1.113 markus 1626: chan_mark_dead(c);
1.104 markus 1627: return -1;
1628: } else if (compat13) {
1.158 markus 1629: buffer_clear(&c->output);
1.194 markus 1630: debug2("channel %d: input draining.", c->self);
1.41 markus 1631: c->type = SSH_CHANNEL_INPUT_DRAINING;
1632: } else {
1633: chan_write_failed(c);
1634: }
1635: return -1;
1.91 markus 1636: }
1.231 reyk 1637: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1638: if (tcgetattr(c->wfd, &tio) == 0 &&
1639: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1640: /*
1641: * Simulate echo to reduce the impact of
1.96 markus 1642: * traffic analysis. We need to match the
1.95 markus 1643: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1644: * (4 byte channel id + buf)
1.91 markus 1645: */
1.95 markus 1646: packet_send_ignore(4 + len);
1.91 markus 1647: packet_send();
1648: }
1.25 markus 1649: }
1.41 markus 1650: buffer_consume(&c->output, len);
1.44 markus 1651: if (compat20 && len > 0) {
1652: c->local_consumed += len;
1653: }
1654: }
1655: return 1;
1656: }
1.241 deraadt 1657:
1.127 itojun 1658: static int
1.237 deraadt 1659: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1660: {
1.214 markus 1661: char buf[CHAN_RBUF];
1.44 markus 1662: int len;
1663:
1.45 markus 1664: /** XXX handle drain efd, too */
1.44 markus 1665: if (c->efd != -1) {
1666: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1667: FD_ISSET(c->efd, writeset) &&
1668: buffer_len(&c->extended) > 0) {
1669: len = write(c->efd, buffer_ptr(&c->extended),
1670: buffer_len(&c->extended));
1.70 markus 1671: debug2("channel %d: written %d to efd %d",
1.44 markus 1672: c->self, len, c->efd);
1.93 markus 1673: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1674: return 1;
1675: if (len <= 0) {
1676: debug2("channel %d: closing write-efd %d",
1677: c->self, c->efd);
1.132 markus 1678: channel_close_fd(&c->efd);
1.93 markus 1679: } else {
1.44 markus 1680: buffer_consume(&c->extended, len);
1681: c->local_consumed += len;
1682: }
1683: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1684: FD_ISSET(c->efd, readset)) {
1685: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1686: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1687: c->self, len, c->efd);
1.93 markus 1688: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1689: return 1;
1690: if (len <= 0) {
1691: debug2("channel %d: closing read-efd %d",
1.45 markus 1692: c->self, c->efd);
1.132 markus 1693: channel_close_fd(&c->efd);
1.93 markus 1694: } else {
1.44 markus 1695: buffer_append(&c->extended, buf, len);
1.93 markus 1696: }
1.44 markus 1697: }
1698: }
1699: return 1;
1700: }
1.241 deraadt 1701:
1.259 stevesk 1702: /* ARGSUSED */
1.127 itojun 1703: static int
1.237 deraadt 1704: channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
1.204 djm 1705: {
1706: char buf[16];
1707: int len;
1708:
1709: /* Monitor control fd to detect if the slave client exits */
1710: if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1711: len = read(c->ctl_fd, buf, sizeof(buf));
1712: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1713: return 1;
1714: if (len <= 0) {
1715: debug2("channel %d: ctl read<=0", c->self);
1716: if (c->type != SSH_CHANNEL_OPEN) {
1717: debug2("channel %d: not open", c->self);
1718: chan_mark_dead(c);
1719: return -1;
1720: } else {
1721: chan_read_failed(c);
1722: chan_write_failed(c);
1723: }
1724: return -1;
1725: } else
1726: fatal("%s: unexpected data on ctl fd", __func__);
1727: }
1728: return 1;
1729: }
1.241 deraadt 1730:
1.204 djm 1731: static int
1.93 markus 1732: channel_check_window(Channel *c)
1.44 markus 1733: {
1.104 markus 1734: if (c->type == SSH_CHANNEL_OPEN &&
1735: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1736: ((c->local_window_max - c->local_window >
1.269 markus 1737: c->local_maxpacket*3) ||
1738: c->local_window < c->local_window_max/2) &&
1.44 markus 1739: c->local_consumed > 0) {
1740: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1741: packet_put_int(c->remote_id);
1742: packet_put_int(c->local_consumed);
1743: packet_send();
1.70 markus 1744: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1745: c->self, c->local_window,
1746: c->local_consumed);
1747: c->local_window += c->local_consumed;
1748: c->local_consumed = 0;
1.1 deraadt 1749: }
1.41 markus 1750: return 1;
1.1 deraadt 1751: }
1752:
1.127 itojun 1753: static void
1.237 deraadt 1754: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1755: {
1.137 markus 1756: if (c->delayed)
1757: return;
1.41 markus 1758: channel_handle_rfd(c, readset, writeset);
1759: channel_handle_wfd(c, readset, writeset);
1.157 markus 1760: if (!compat20)
1.137 markus 1761: return;
1.44 markus 1762: channel_handle_efd(c, readset, writeset);
1.204 djm 1763: channel_handle_ctl(c, readset, writeset);
1.93 markus 1764: channel_check_window(c);
1.44 markus 1765: }
1766:
1.259 stevesk 1767: /* ARGSUSED */
1.127 itojun 1768: static void
1.237 deraadt 1769: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1770: {
1.41 markus 1771: int len;
1.180 deraadt 1772:
1.41 markus 1773: /* Send buffered output data to the socket. */
1774: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1775: len = write(c->sock, buffer_ptr(&c->output),
1776: buffer_len(&c->output));
1777: if (len <= 0)
1.158 markus 1778: buffer_clear(&c->output);
1.41 markus 1779: else
1780: buffer_consume(&c->output, len);
1781: }
1782: }
1.25 markus 1783:
1.127 itojun 1784: static void
1.44 markus 1785: channel_handler_init_20(void)
1786: {
1.157 markus 1787: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1788: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1789: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1790: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1791: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1792: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1793: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1794: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1795:
1.157 markus 1796: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1797: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1798: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1799: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1800: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1801: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1802: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1803: }
1804:
1.127 itojun 1805: static void
1.41 markus 1806: channel_handler_init_13(void)
1807: {
1808: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1809: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1810: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1811: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1812: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1813: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1814: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1815: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1816: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1817:
1.157 markus 1818: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1819: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1820: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1821: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1822: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1823: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1824: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1825: }
1.25 markus 1826:
1.127 itojun 1827: static void
1.41 markus 1828: channel_handler_init_15(void)
1829: {
1.157 markus 1830: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1831: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1832: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1833: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1834: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1835: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1836: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1837:
1.41 markus 1838: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1839: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1840: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1841: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1842: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1843: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1844: }
1.27 markus 1845:
1.127 itojun 1846: static void
1.41 markus 1847: channel_handler_init(void)
1848: {
1849: int i;
1.180 deraadt 1850:
1.148 deraadt 1851: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1852: channel_pre[i] = NULL;
1853: channel_post[i] = NULL;
1854: }
1.44 markus 1855: if (compat20)
1856: channel_handler_init_20();
1857: else if (compat13)
1.41 markus 1858: channel_handler_init_13();
1859: else
1860: channel_handler_init_15();
1861: }
1.25 markus 1862:
1.140 markus 1863: /* gc dead channels */
1864: static void
1865: channel_garbage_collect(Channel *c)
1866: {
1867: if (c == NULL)
1868: return;
1869: if (c->detach_user != NULL) {
1.225 djm 1870: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1871: return;
1.194 markus 1872: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1873: c->detach_user(c->self, NULL);
1874: /* if we still have a callback */
1875: if (c->detach_user != NULL)
1876: return;
1.194 markus 1877: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1878: }
1879: if (!chan_is_dead(c, 1))
1880: return;
1.194 markus 1881: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1882: channel_free(c);
1883: }
1884:
1.127 itojun 1885: static void
1.237 deraadt 1886: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
1.41 markus 1887: {
1888: static int did_init = 0;
1.209 avsm 1889: u_int i;
1.41 markus 1890: Channel *c;
1.25 markus 1891:
1.41 markus 1892: if (!did_init) {
1893: channel_handler_init();
1894: did_init = 1;
1895: }
1896: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1897: c = channels[i];
1898: if (c == NULL)
1.41 markus 1899: continue;
1.118 markus 1900: if (ftab[c->type] != NULL)
1901: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1902: channel_garbage_collect(c);
1.1 deraadt 1903: }
1904: }
1905:
1.121 markus 1906: /*
1907: * Allocate/update select bitmasks and add any bits relevant to channels in
1908: * select bitmasks.
1909: */
1.49 markus 1910: void
1.100 markus 1911: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.209 avsm 1912: u_int *nallocp, int rekeying)
1.41 markus 1913: {
1.243 djm 1914: u_int n, sz, nfdset;
1.84 markus 1915:
1916: n = MAX(*maxfdp, channel_max_fd);
1917:
1.243 djm 1918: nfdset = howmany(n+1, NFDBITS);
1919: /* Explicitly test here, because xrealloc isn't always called */
1920: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1921: fatal("channel_prepare_select: max_fd (%d) is too large", n);
1922: sz = nfdset * sizeof(fd_mask);
1923:
1.132 markus 1924: /* perhaps check sz < nalloc/2 and shrink? */
1925: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 1926: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1927: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 1928: *nallocp = sz;
1.84 markus 1929: }
1.132 markus 1930: *maxfdp = n;
1.84 markus 1931: memset(*readsetp, 0, sz);
1932: memset(*writesetp, 0, sz);
1933:
1.100 markus 1934: if (!rekeying)
1935: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1936: }
1937:
1.121 markus 1938: /*
1939: * After select, perform any appropriate operations for channels which have
1940: * events pending.
1941: */
1.49 markus 1942: void
1.237 deraadt 1943: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 1944: {
1945: channel_handler(channel_post, readset, writeset);
1946: }
1947:
1.121 markus 1948:
1.84 markus 1949: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 1950: void
1.142 itojun 1951: channel_output_poll(void)
1.1 deraadt 1952: {
1.41 markus 1953: Channel *c;
1.209 avsm 1954: u_int i, len;
1.1 deraadt 1955:
1.25 markus 1956: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1957: c = channels[i];
1958: if (c == NULL)
1959: continue;
1.37 markus 1960:
1.121 markus 1961: /*
1962: * We are only interested in channels that can have buffered
1963: * incoming data.
1964: */
1.37 markus 1965: if (compat13) {
1.41 markus 1966: if (c->type != SSH_CHANNEL_OPEN &&
1967: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1968: continue;
1969: } else {
1.41 markus 1970: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1971: continue;
1972: }
1.46 markus 1973: if (compat20 &&
1974: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1975: /* XXX is this true? */
1.140 markus 1976: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1977: continue;
1978: }
1.25 markus 1979:
1980: /* Get the amount of buffered data for this channel. */
1.93 markus 1981: if ((c->istate == CHAN_INPUT_OPEN ||
1982: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1983: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 1984: if (c->datagram) {
1985: if (len > 0) {
1986: u_char *data;
1987: u_int dlen;
1988:
1989: data = buffer_get_string(&c->input,
1990: &dlen);
1991: packet_start(SSH2_MSG_CHANNEL_DATA);
1992: packet_put_int(c->remote_id);
1993: packet_put_string(data, dlen);
1994: packet_send();
1995: c->remote_window -= dlen + 4;
1996: xfree(data);
1997: }
1998: continue;
1999: }
1.121 markus 2000: /*
2001: * Send some data for the other side over the secure
2002: * connection.
2003: */
1.44 markus 2004: if (compat20) {
2005: if (len > c->remote_window)
2006: len = c->remote_window;
2007: if (len > c->remote_maxpacket)
2008: len = c->remote_maxpacket;
1.25 markus 2009: } else {
1.44 markus 2010: if (packet_is_interactive()) {
2011: if (len > 1024)
2012: len = 512;
2013: } else {
2014: /* Keep the packets at reasonable size. */
2015: if (len > packet_get_maxsize()/2)
2016: len = packet_get_maxsize()/2;
2017: }
1.25 markus 2018: }
1.41 markus 2019: if (len > 0) {
1.44 markus 2020: packet_start(compat20 ?
2021: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2022: packet_put_int(c->remote_id);
2023: packet_put_string(buffer_ptr(&c->input), len);
2024: packet_send();
2025: buffer_consume(&c->input, len);
2026: c->remote_window -= len;
2027: }
2028: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2029: if (compat13)
2030: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2031: /*
2032: * input-buffer is empty and read-socket shutdown:
1.172 markus 2033: * tell peer, that we will not send more data: send IEOF.
2034: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2035: */
1.172 markus 2036: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2037: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2038: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2039: else
2040: chan_ibuf_empty(c);
1.25 markus 2041: }
1.44 markus 2042: /* Send extended data, i.e. stderr */
2043: if (compat20 &&
1.172 markus 2044: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2045: c->remote_window > 0 &&
2046: (len = buffer_len(&c->extended)) > 0 &&
2047: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2048: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2049: c->self, c->remote_window, buffer_len(&c->extended),
2050: c->extended_usage);
1.44 markus 2051: if (len > c->remote_window)
2052: len = c->remote_window;
2053: if (len > c->remote_maxpacket)
2054: len = c->remote_maxpacket;
2055: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2056: packet_put_int(c->remote_id);
2057: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2058: packet_put_string(buffer_ptr(&c->extended), len);
2059: packet_send();
2060: buffer_consume(&c->extended, len);
2061: c->remote_window -= len;
1.93 markus 2062: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2063: }
1.25 markus 2064: }
1.1 deraadt 2065: }
2066:
1.121 markus 2067:
2068: /* -- protocol input */
1.249 djm 2069:
2070: /* ARGSUSED */
1.49 markus 2071: void
1.154 markus 2072: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2073: {
1.37 markus 2074: int id;
1.25 markus 2075: char *data;
1.77 markus 2076: u_int data_len;
1.41 markus 2077: Channel *c;
1.25 markus 2078:
2079: /* Get the channel number and verify it. */
1.37 markus 2080: id = packet_get_int();
1.41 markus 2081: c = channel_lookup(id);
2082: if (c == NULL)
1.37 markus 2083: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2084:
2085: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2086: if (c->type != SSH_CHANNEL_OPEN &&
2087: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 2088: return;
2089:
1.25 markus 2090: /* Get the data. */
1.274 markus 2091: data = packet_get_string_ptr(&data_len);
1.200 markus 2092:
2093: /*
2094: * Ignore data for protocol > 1.3 if output end is no longer open.
2095: * For protocol 2 the sending side is reducing its window as it sends
2096: * data, so we must 'fake' consumption of the data in order to ensure
2097: * that window updates are sent back. Otherwise the connection might
2098: * deadlock.
2099: */
2100: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2101: if (compat20) {
2102: c->local_window -= data_len;
2103: c->local_consumed += data_len;
2104: }
2105: return;
2106: }
1.41 markus 2107:
1.143 deraadt 2108: if (compat20) {
1.44 markus 2109: if (data_len > c->local_maxpacket) {
1.188 itojun 2110: logit("channel %d: rcvd big packet %d, maxpack %d",
1.44 markus 2111: c->self, data_len, c->local_maxpacket);
2112: }
2113: if (data_len > c->local_window) {
1.188 itojun 2114: logit("channel %d: rcvd too much data %d, win %d",
1.44 markus 2115: c->self, data_len, c->local_window);
2116: return;
2117: }
2118: c->local_window -= data_len;
2119: }
1.228 reyk 2120: if (c->datagram)
2121: buffer_put_string(&c->output, data, data_len);
2122: else
2123: buffer_append(&c->output, data, data_len);
1.274 markus 2124: packet_check_eom();
1.1 deraadt 2125: }
1.121 markus 2126:
1.249 djm 2127: /* ARGSUSED */
1.49 markus 2128: void
1.154 markus 2129: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2130: {
2131: int id;
2132: char *data;
1.177 markus 2133: u_int data_len, tcode;
1.44 markus 2134: Channel *c;
2135:
2136: /* Get the channel number and verify it. */
2137: id = packet_get_int();
2138: c = channel_lookup(id);
2139:
2140: if (c == NULL)
2141: packet_disconnect("Received extended_data for bad channel %d.", id);
2142: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2143: logit("channel %d: ext data for non open", id);
1.44 markus 2144: return;
1.172 markus 2145: }
2146: if (c->flags & CHAN_EOF_RCVD) {
2147: if (datafellows & SSH_BUG_EXTEOF)
2148: debug("channel %d: accepting ext data after eof", id);
2149: else
2150: packet_disconnect("Received extended_data after EOF "
2151: "on channel %d.", id);
1.44 markus 2152: }
2153: tcode = packet_get_int();
2154: if (c->efd == -1 ||
2155: c->extended_usage != CHAN_EXTENDED_WRITE ||
2156: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2157: logit("channel %d: bad ext data", c->self);
1.44 markus 2158: return;
2159: }
2160: data = packet_get_string(&data_len);
1.152 markus 2161: packet_check_eom();
1.44 markus 2162: if (data_len > c->local_window) {
1.188 itojun 2163: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2164: c->self, data_len, c->local_window);
2165: xfree(data);
2166: return;
2167: }
1.70 markus 2168: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2169: c->local_window -= data_len;
2170: buffer_append(&c->extended, data, data_len);
2171: xfree(data);
2172: }
2173:
1.249 djm 2174: /* ARGSUSED */
1.49 markus 2175: void
1.154 markus 2176: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2177: {
2178: int id;
2179: Channel *c;
2180:
2181: id = packet_get_int();
1.152 markus 2182: packet_check_eom();
1.41 markus 2183: c = channel_lookup(id);
2184: if (c == NULL)
2185: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2186: chan_rcvd_ieof(c);
1.133 markus 2187:
2188: /* XXX force input close */
1.156 markus 2189: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2190: debug("channel %d: FORCE input drain", c->self);
2191: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2192: if (buffer_len(&c->input) == 0)
2193: chan_ibuf_empty(c);
1.133 markus 2194: }
2195:
1.41 markus 2196: }
1.1 deraadt 2197:
1.249 djm 2198: /* ARGSUSED */
1.49 markus 2199: void
1.154 markus 2200: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2201: {
1.41 markus 2202: int id;
2203: Channel *c;
1.1 deraadt 2204:
1.41 markus 2205: id = packet_get_int();
1.152 markus 2206: packet_check_eom();
1.41 markus 2207: c = channel_lookup(id);
2208: if (c == NULL)
2209: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2210:
2211: /*
2212: * Send a confirmation that we have closed the channel and no more
2213: * data is coming for it.
2214: */
1.25 markus 2215: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2216: packet_put_int(c->remote_id);
1.25 markus 2217: packet_send();
2218:
1.27 markus 2219: /*
2220: * If the channel is in closed state, we have sent a close request,
2221: * and the other side will eventually respond with a confirmation.
2222: * Thus, we cannot free the channel here, because then there would be
2223: * no-one to receive the confirmation. The channel gets freed when
2224: * the confirmation arrives.
2225: */
1.41 markus 2226: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2227: /*
2228: * Not a closed channel - mark it as draining, which will
2229: * cause it to be freed later.
2230: */
1.158 markus 2231: buffer_clear(&c->input);
1.41 markus 2232: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2233: }
1.1 deraadt 2234: }
2235:
1.41 markus 2236: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2237: /* ARGSUSED */
1.49 markus 2238: void
1.154 markus 2239: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2240: {
2241: int id = packet_get_int();
2242: Channel *c = channel_lookup(id);
1.151 markus 2243:
1.152 markus 2244: packet_check_eom();
1.41 markus 2245: if (c == NULL)
2246: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2247: chan_rcvd_oclose(c);
2248: }
1.1 deraadt 2249:
1.249 djm 2250: /* ARGSUSED */
1.49 markus 2251: void
1.154 markus 2252: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2253: {
1.41 markus 2254: int id = packet_get_int();
2255: Channel *c = channel_lookup(id);
1.1 deraadt 2256:
1.152 markus 2257: packet_check_eom();
1.41 markus 2258: if (c == NULL)
2259: packet_disconnect("Received close confirmation for "
2260: "out-of-range channel %d.", id);
2261: if (c->type != SSH_CHANNEL_CLOSED)
2262: packet_disconnect("Received close confirmation for "
2263: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2264: channel_free(c);
1.1 deraadt 2265: }
2266:
1.249 djm 2267: /* ARGSUSED */
1.49 markus 2268: void
1.154 markus 2269: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2270: {
1.41 markus 2271: int id, remote_id;
2272: Channel *c;
1.1 deraadt 2273:
1.41 markus 2274: id = packet_get_int();
2275: c = channel_lookup(id);
1.25 markus 2276:
1.41 markus 2277: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2278: packet_disconnect("Received open confirmation for "
2279: "non-opening channel %d.", id);
2280: remote_id = packet_get_int();
1.27 markus 2281: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2282: c->remote_id = remote_id;
2283: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2284:
2285: if (compat20) {
2286: c->remote_window = packet_get_int();
2287: c->remote_maxpacket = packet_get_int();
1.275 djm 2288: if (c->open_confirm) {
1.70 markus 2289: debug2("callback start");
1.275 djm 2290: c->open_confirm(c->self, c->open_confirm_ctx);
1.70 markus 2291: debug2("callback done");
1.44 markus 2292: }
1.194 markus 2293: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2294: c->remote_window, c->remote_maxpacket);
2295: }
1.152 markus 2296: packet_check_eom();
1.1 deraadt 2297: }
2298:
1.127 itojun 2299: static char *
1.114 markus 2300: reason2txt(int reason)
2301: {
1.143 deraadt 2302: switch (reason) {
1.114 markus 2303: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2304: return "administratively prohibited";
2305: case SSH2_OPEN_CONNECT_FAILED:
2306: return "connect failed";
2307: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2308: return "unknown channel type";
2309: case SSH2_OPEN_RESOURCE_SHORTAGE:
2310: return "resource shortage";
2311: }
1.117 stevesk 2312: return "unknown reason";
1.114 markus 2313: }
2314:
1.249 djm 2315: /* ARGSUSED */
1.49 markus 2316: void
1.154 markus 2317: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2318: {
1.86 markus 2319: int id, reason;
2320: char *msg = NULL, *lang = NULL;
1.41 markus 2321: Channel *c;
2322:
2323: id = packet_get_int();
2324: c = channel_lookup(id);
1.25 markus 2325:
1.41 markus 2326: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2327: packet_disconnect("Received open failure for "
2328: "non-opening channel %d.", id);
1.44 markus 2329: if (compat20) {
1.86 markus 2330: reason = packet_get_int();
1.110 markus 2331: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2332: msg = packet_get_string(NULL);
2333: lang = packet_get_string(NULL);
2334: }
1.188 itojun 2335: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2336: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 2337: if (msg != NULL)
2338: xfree(msg);
2339: if (lang != NULL)
2340: xfree(lang);
1.44 markus 2341: }
1.152 markus 2342: packet_check_eom();
1.291 djm 2343: /* Schedule the channel for cleanup/deletion. */
2344: chan_mark_dead(c);
1.44 markus 2345: }
2346:
1.249 djm 2347: /* ARGSUSED */
1.121 markus 2348: void
1.154 markus 2349: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2350: {
2351: Channel *c;
1.178 markus 2352: int id;
2353: u_int adjust;
1.121 markus 2354:
2355: if (!compat20)
2356: return;
2357:
2358: /* Get the channel number and verify it. */
2359: id = packet_get_int();
2360: c = channel_lookup(id);
1.1 deraadt 2361:
1.229 markus 2362: if (c == NULL) {
2363: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2364: return;
2365: }
2366: adjust = packet_get_int();
1.152 markus 2367: packet_check_eom();
1.178 markus 2368: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2369: c->remote_window += adjust;
2370: }
1.1 deraadt 2371:
1.249 djm 2372: /* ARGSUSED */
1.121 markus 2373: void
1.154 markus 2374: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2375: {
1.121 markus 2376: Channel *c = NULL;
2377: u_short host_port;
2378: char *host, *originator_string;
1.276 djm 2379: int remote_id;
1.121 markus 2380:
2381: remote_id = packet_get_int();
2382: host = packet_get_string(NULL);
2383: host_port = packet_get_int();
1.25 markus 2384:
1.121 markus 2385: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2386: originator_string = packet_get_string(NULL);
2387: } else {
2388: originator_string = xstrdup("unknown (remote did not supply name)");
2389: }
1.152 markus 2390: packet_check_eom();
1.276 djm 2391: c = channel_connect_to(host, host_port,
2392: "connected socket", originator_string);
1.190 markus 2393: xfree(originator_string);
1.276 djm 2394: xfree(host);
1.121 markus 2395: if (c == NULL) {
2396: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2397: packet_put_int(remote_id);
2398: packet_send();
1.276 djm 2399: } else
2400: c->remote_id = remote_id;
1.1 deraadt 2401: }
2402:
1.275 djm 2403: /* ARGSUSED */
2404: void
2405: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2406: {
2407: Channel *c;
2408: struct channel_confirm *cc;
1.289 markus 2409: int id;
1.275 djm 2410:
2411: /* Reset keepalive timeout */
1.296 ! andreas 2412: packet_set_alive_timeouts(0);
1.275 djm 2413:
1.289 markus 2414: id = packet_get_int();
1.275 djm 2415: packet_check_eom();
2416:
1.289 markus 2417: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2418:
1.289 markus 2419: if ((c = channel_lookup(id)) == NULL) {
2420: logit("channel_input_status_confirm: %d: unknown", id);
1.275 djm 2421: return;
2422: }
2423: ;
2424: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
2425: return;
2426: cc->cb(type, c, cc->ctx);
2427: TAILQ_REMOVE(&c->status_confirms, cc, entry);
2428: bzero(cc, sizeof(*cc));
2429: xfree(cc);
2430: }
1.121 markus 2431:
2432: /* -- tcp forwarding */
1.135 markus 2433:
2434: void
2435: channel_set_af(int af)
2436: {
2437: IPv4or6 = af;
2438: }
1.121 markus 2439:
1.160 markus 2440: static int
1.295 djm 2441: channel_setup_fwd_listener(int type, const char *listen_addr,
2442: u_short listen_port, int *allocated_listen_port,
1.160 markus 2443: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2444: {
1.113 markus 2445: Channel *c;
1.226 djm 2446: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2447: struct addrinfo hints, *ai, *aitop;
1.212 djm 2448: const char *host, *addr;
1.35 markus 2449: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2450: in_port_t *lport_p;
1.25 markus 2451:
1.160 markus 2452: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2453: listen_addr : host_to_connect;
1.212 djm 2454: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2455:
1.160 markus 2456: if (host == NULL) {
2457: error("No forward host name.");
1.218 markus 2458: return 0;
1.73 markus 2459: }
1.294 djm 2460: if (strlen(host) >= NI_MAXHOST) {
1.87 markus 2461: error("Forward host name too long.");
1.218 markus 2462: return 0;
1.87 markus 2463: }
1.25 markus 2464:
1.28 markus 2465: /*
1.212 djm 2466: * Determine whether or not a port forward listens to loopback,
1.213 deraadt 2467: * specified address or wildcard. On the client, a specified bind
2468: * address will always override gateway_ports. On the server, a
2469: * gateway_ports of 1 (``yes'') will override the client's
2470: * specification and force a wildcard bind, whereas a value of 2
2471: * (``clientspecified'') will bind to whatever address the client
1.212 djm 2472: * asked for.
2473: *
2474: * Special-case listen_addrs are:
2475: *
2476: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2477: * "" (empty string), "*" -> wildcard v4/v6
2478: * "localhost" -> loopback v4/v6
2479: */
2480: addr = NULL;
2481: if (listen_addr == NULL) {
2482: /* No address specified: default to gateway_ports setting */
2483: if (gateway_ports)
2484: wildcard = 1;
2485: } else if (gateway_ports || is_client) {
2486: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
1.272 djm 2487: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
1.212 djm 2488: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2489: (!is_client && gateway_ports == 1))
2490: wildcard = 1;
2491: else if (strcmp(listen_addr, "localhost") != 0)
2492: addr = listen_addr;
2493: }
2494:
2495: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2496: type, wildcard, (addr == NULL) ? "NULL" : addr);
2497:
2498: /*
1.35 markus 2499: * getaddrinfo returns a loopback address if the hostname is
2500: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2501: */
1.35 markus 2502: memset(&hints, 0, sizeof(hints));
2503: hints.ai_family = IPv4or6;
1.212 djm 2504: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2505: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2506: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2507: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2508: if (addr == NULL) {
2509: /* This really shouldn't happen */
2510: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2511: ssh_gai_strerror(r));
1.212 djm 2512: } else {
1.218 markus 2513: error("channel_setup_fwd_listener: "
1.271 dtucker 2514: "getaddrinfo(%.64s): %s", addr,
2515: ssh_gai_strerror(r));
1.212 djm 2516: }
1.218 markus 2517: return 0;
1.212 djm 2518: }
1.295 djm 2519: if (allocated_listen_port != NULL)
2520: *allocated_listen_port = 0;
1.35 markus 2521: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2522: switch (ai->ai_family) {
2523: case AF_INET:
2524: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2525: sin_port;
2526: break;
2527: case AF_INET6:
2528: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2529: sin6_port;
2530: break;
2531: default:
1.35 markus 2532: continue;
1.295 djm 2533: }
2534: /*
2535: * If allocating a port for -R forwards, then use the
2536: * same port for all address families.
2537: */
2538: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2539: allocated_listen_port != NULL && *allocated_listen_port > 0)
2540: *lport_p = htons(*allocated_listen_port);
2541:
1.35 markus 2542: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2543: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2544: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2545: continue;
2546: }
2547: /* Create a port to listen for the host. */
1.189 markus 2548: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2549: if (sock < 0) {
2550: /* this is no error since kernel may not support ipv6 */
2551: verbose("socket: %.100s", strerror(errno));
2552: continue;
2553: }
1.226 djm 2554:
2555: channel_set_reuseaddr(sock);
1.182 stevesk 2556:
1.295 djm 2557: debug("Local forwarding listening on %s port %s.",
2558: ntop, strport);
1.35 markus 2559:
2560: /* Bind the socket to the address. */
2561: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2562: /* address can be in use ipv6 address is already bound */
2563: verbose("bind: %.100s", strerror(errno));
2564: close(sock);
2565: continue;
2566: }
2567: /* Start listening for connections on the socket. */
1.199 markus 2568: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2569: error("listen: %.100s", strerror(errno));
2570: close(sock);
2571: continue;
2572: }
1.295 djm 2573:
2574: /*
2575: * listen_port == 0 requests a dynamically allocated port -
2576: * record what we got.
2577: */
2578: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2579: allocated_listen_port != NULL &&
2580: *allocated_listen_port == 0) {
2581: *allocated_listen_port = get_sock_port(sock, 1);
2582: debug("Allocated listen port %d",
2583: *allocated_listen_port);
2584: }
2585:
1.35 markus 2586: /* Allocate a channel number for the socket. */
1.121 markus 2587: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2588: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2589: 0, "port listener", 1);
1.293 djm 2590: c->path = xstrdup(host);
1.113 markus 2591: c->host_port = port_to_connect;
2592: c->listening_port = listen_port;
1.35 markus 2593: success = 1;
2594: }
2595: if (success == 0)
1.160 markus 2596: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2597: listen_port);
1.35 markus 2598: freeaddrinfo(aitop);
1.87 markus 2599: return success;
1.25 markus 2600: }
1.1 deraadt 2601:
1.202 djm 2602: int
2603: channel_cancel_rport_listener(const char *host, u_short port)
2604: {
1.209 avsm 2605: u_int i;
2606: int found = 0;
1.202 djm 2607:
1.213 deraadt 2608: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2609: Channel *c = channels[i];
2610:
2611: if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
1.293 djm 2612: strcmp(c->path, host) == 0 && c->listening_port == port) {
1.210 djm 2613: debug2("%s: close channel %d", __func__, i);
1.202 djm 2614: channel_free(c);
2615: found = 1;
2616: }
2617: }
2618:
2619: return (found);
2620: }
2621:
1.160 markus 2622: /* protocol local port fwd, used by ssh (and sshd in v1) */
2623: int
1.212 djm 2624: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2625: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2626: {
2627: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.295 djm 2628: listen_host, listen_port, NULL, host_to_connect, port_to_connect,
1.212 djm 2629: gateway_ports);
1.160 markus 2630: }
2631:
2632: /* protocol v2 remote port fwd, used by sshd */
2633: int
2634: channel_setup_remote_fwd_listener(const char *listen_address,
1.295 djm 2635: u_short listen_port, int *allocated_listen_port, int gateway_ports)
1.160 markus 2636: {
2637: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
1.295 djm 2638: listen_address, listen_port, allocated_listen_port,
2639: NULL, 0, gateway_ports);
1.160 markus 2640: }
2641:
1.27 markus 2642: /*
2643: * Initiate forwarding of connections to port "port" on remote host through
2644: * the secure channel to host:port from local side.
2645: */
1.1 deraadt 2646:
1.253 markus 2647: int
1.212 djm 2648: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2649: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2650: {
1.153 markus 2651: int type, success = 0;
1.73 markus 2652:
1.25 markus 2653: /* Record locally that connection to this host/port is permitted. */
2654: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2655: fatal("channel_request_remote_forwarding: too many forwards");
2656:
2657: /* Send the forward request to the remote side. */
1.44 markus 2658: if (compat20) {
1.212 djm 2659: const char *address_to_bind;
1.267 djm 2660: if (listen_host == NULL) {
2661: if (datafellows & SSH_BUG_RFWD_ADDR)
2662: address_to_bind = "127.0.0.1";
2663: else
2664: address_to_bind = "localhost";
2665: } else if (*listen_host == '\0' ||
2666: strcmp(listen_host, "*") == 0) {
2667: if (datafellows & SSH_BUG_RFWD_ADDR)
2668: address_to_bind = "0.0.0.0";
2669: else
2670: address_to_bind = "";
2671: } else
1.212 djm 2672: address_to_bind = listen_host;
2673:
1.44 markus 2674: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2675: packet_put_cstring("tcpip-forward");
1.173 markus 2676: packet_put_char(1); /* boolean: want reply */
1.44 markus 2677: packet_put_cstring(address_to_bind);
2678: packet_put_int(listen_port);
1.73 markus 2679: packet_send();
2680: packet_write_wait();
2681: /* Assume that server accepts the request */
2682: success = 1;
1.44 markus 2683: } else {
2684: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2685: packet_put_int(listen_port);
2686: packet_put_cstring(host_to_connect);
1.44 markus 2687: packet_put_int(port_to_connect);
2688: packet_send();
2689: packet_write_wait();
1.73 markus 2690:
2691: /* Wait for response from the remote side. */
1.153 markus 2692: type = packet_read();
1.73 markus 2693: switch (type) {
2694: case SSH_SMSG_SUCCESS:
2695: success = 1;
2696: break;
2697: case SSH_SMSG_FAILURE:
2698: break;
2699: default:
2700: /* Unknown packet */
2701: packet_disconnect("Protocol error for port forward request:"
2702: "received packet type %d.", type);
2703: }
2704: }
2705: if (success) {
2706: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2707: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2708: permitted_opens[num_permitted_opens].listen_port = listen_port;
2709: num_permitted_opens++;
1.44 markus 2710: }
1.253 markus 2711: return (success ? 0 : -1);
1.1 deraadt 2712: }
2713:
1.27 markus 2714: /*
1.208 deraadt 2715: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 2716: * local side.
2717: */
2718: void
1.212 djm 2719: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 2720: {
2721: int i;
2722:
2723: if (!compat20)
2724: return;
2725:
2726: for (i = 0; i < num_permitted_opens; i++) {
1.208 deraadt 2727: if (permitted_opens[i].host_to_connect != NULL &&
1.202 djm 2728: permitted_opens[i].listen_port == port)
2729: break;
2730: }
2731: if (i >= num_permitted_opens) {
2732: debug("%s: requested forward not found", __func__);
2733: return;
2734: }
2735: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2736: packet_put_cstring("cancel-tcpip-forward");
2737: packet_put_char(0);
1.212 djm 2738: packet_put_cstring(host == NULL ? "" : host);
1.202 djm 2739: packet_put_int(port);
2740: packet_send();
2741:
2742: permitted_opens[i].listen_port = 0;
2743: permitted_opens[i].port_to_connect = 0;
1.227 stevesk 2744: xfree(permitted_opens[i].host_to_connect);
1.202 djm 2745: permitted_opens[i].host_to_connect = NULL;
2746: }
2747:
2748: /*
1.27 markus 2749: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2750: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 2751: * message if there was an error).
1.27 markus 2752: */
1.253 markus 2753: int
1.56 markus 2754: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2755: {
1.31 markus 2756: u_short port, host_port;
1.253 markus 2757: int success = 0;
1.25 markus 2758: char *hostname;
1.1 deraadt 2759:
1.25 markus 2760: /* Get arguments from the packet. */
2761: port = packet_get_int();
2762: hostname = packet_get_string(NULL);
2763: host_port = packet_get_int();
2764:
1.27 markus 2765: /*
2766: * Check that an unprivileged user is not trying to forward a
2767: * privileged port.
2768: */
1.25 markus 2769: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 2770: packet_disconnect(
2771: "Requested forwarding of port %d but user is not root.",
2772: port);
2773: if (host_port == 0)
2774: packet_disconnect("Dynamic forwarding denied.");
2775:
1.73 markus 2776: /* Initiate forwarding */
1.253 markus 2777: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 2778: host_port, gateway_ports);
1.25 markus 2779:
2780: /* Free the argument string. */
2781: xfree(hostname);
1.253 markus 2782:
2783: return (success ? 0 : -1);
1.1 deraadt 2784: }
2785:
1.99 markus 2786: /*
2787: * Permits opening to any host/port if permitted_opens[] is empty. This is
2788: * usually called by the server, because the user could connect to any port
2789: * anyway, and the server has no way to know but to trust the client anyway.
2790: */
2791: void
1.142 itojun 2792: channel_permit_all_opens(void)
1.99 markus 2793: {
2794: if (num_permitted_opens == 0)
2795: all_opens_permitted = 1;
2796: }
2797:
1.101 markus 2798: void
1.99 markus 2799: channel_add_permitted_opens(char *host, int port)
2800: {
2801: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1.253 markus 2802: fatal("channel_add_permitted_opens: too many forwards");
1.99 markus 2803: debug("allow port forwarding to host %s port %d", host, port);
2804:
2805: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2806: permitted_opens[num_permitted_opens].port_to_connect = port;
2807: num_permitted_opens++;
2808:
2809: all_opens_permitted = 0;
2810: }
2811:
1.258 dtucker 2812: int
1.257 dtucker 2813: channel_add_adm_permitted_opens(char *host, int port)
2814: {
2815: if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2816: fatal("channel_add_adm_permitted_opens: too many forwards");
1.258 dtucker 2817: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 2818:
2819: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
2820: = xstrdup(host);
2821: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.258 dtucker 2822: return ++num_adm_permitted_opens;
1.257 dtucker 2823: }
2824:
2825: void
1.99 markus 2826: channel_clear_permitted_opens(void)
2827: {
2828: int i;
2829:
2830: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2831: if (permitted_opens[i].host_to_connect != NULL)
2832: xfree(permitted_opens[i].host_to_connect);
1.99 markus 2833: num_permitted_opens = 0;
1.257 dtucker 2834: }
2835:
2836: void
2837: channel_clear_adm_permitted_opens(void)
2838: {
2839: int i;
1.99 markus 2840:
1.257 dtucker 2841: for (i = 0; i < num_adm_permitted_opens; i++)
2842: if (permitted_adm_opens[i].host_to_connect != NULL)
2843: xfree(permitted_adm_opens[i].host_to_connect);
2844: num_adm_permitted_opens = 0;
1.278 dtucker 2845: }
2846:
2847: void
2848: channel_print_adm_permitted_opens(void)
2849: {
1.286 djm 2850: int i;
1.278 dtucker 2851:
1.290 stevesk 2852: printf("permitopen");
1.288 stevesk 2853: if (num_adm_permitted_opens == 0) {
1.290 stevesk 2854: printf(" any\n");
1.288 stevesk 2855: return;
2856: }
1.278 dtucker 2857: for (i = 0; i < num_adm_permitted_opens; i++)
2858: if (permitted_adm_opens[i].host_to_connect != NULL)
2859: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
2860: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 2861: printf("\n");
1.99 markus 2862: }
2863:
1.276 djm 2864: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 2865: static int
1.276 djm 2866: connect_next(struct channel_connect *cctx)
1.41 markus 2867: {
1.276 djm 2868: int sock, saved_errno;
1.41 markus 2869: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2870:
1.276 djm 2871: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
2872: if (cctx->ai->ai_family != AF_INET &&
2873: cctx->ai->ai_family != AF_INET6)
1.41 markus 2874: continue;
1.276 djm 2875: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
2876: ntop, sizeof(ntop), strport, sizeof(strport),
2877: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
2878: error("connect_next: getnameinfo failed");
1.41 markus 2879: continue;
2880: }
1.276 djm 2881: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
2882: cctx->ai->ai_protocol)) == -1) {
2883: if (cctx->ai->ai_next == NULL)
1.186 djm 2884: error("socket: %.100s", strerror(errno));
2885: else
2886: verbose("socket: %.100s", strerror(errno));
1.41 markus 2887: continue;
2888: }
1.205 djm 2889: if (set_nonblock(sock) == -1)
2890: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 2891: if (connect(sock, cctx->ai->ai_addr,
2892: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
2893: debug("connect_next: host %.100s ([%.100s]:%s): "
2894: "%.100s", cctx->host, ntop, strport,
1.41 markus 2895: strerror(errno));
1.276 djm 2896: saved_errno = errno;
1.41 markus 2897: close(sock);
1.276 djm 2898: errno = saved_errno;
1.89 stevesk 2899: continue; /* fail -- try next */
1.41 markus 2900: }
1.276 djm 2901: debug("connect_next: host %.100s ([%.100s]:%s) "
2902: "in progress, fd=%d", cctx->host, ntop, strport, sock);
2903: cctx->ai = cctx->ai->ai_next;
2904: set_nodelay(sock);
2905: return sock;
2906: }
2907: return -1;
2908: }
1.41 markus 2909:
1.276 djm 2910: static void
2911: channel_connect_ctx_free(struct channel_connect *cctx)
2912: {
2913: xfree(cctx->host);
2914: if (cctx->aitop)
2915: freeaddrinfo(cctx->aitop);
2916: bzero(cctx, sizeof(*cctx));
2917: cctx->host = NULL;
2918: cctx->ai = cctx->aitop = NULL;
2919: }
2920:
2921: /* Return CONNECTING channel to remote host, port */
2922: static Channel *
2923: connect_to(const char *host, u_short port, char *ctype, char *rname)
2924: {
2925: struct addrinfo hints;
2926: int gaierr;
2927: int sock = -1;
2928: char strport[NI_MAXSERV];
2929: struct channel_connect cctx;
2930: Channel *c;
2931:
1.284 djm 2932: memset(&cctx, 0, sizeof(cctx));
1.276 djm 2933: memset(&hints, 0, sizeof(hints));
2934: hints.ai_family = IPv4or6;
2935: hints.ai_socktype = SOCK_STREAM;
2936: snprintf(strport, sizeof strport, "%d", port);
2937: if ((gaierr = getaddrinfo(host, strport, &hints, &cctx.aitop)) != 0) {
2938: error("connect_to %.100s: unknown host (%s)", host,
2939: ssh_gai_strerror(gaierr));
2940: return NULL;
1.41 markus 2941: }
1.276 djm 2942:
2943: cctx.host = xstrdup(host);
2944: cctx.port = port;
2945: cctx.ai = cctx.aitop;
2946:
2947: if ((sock = connect_next(&cctx)) == -1) {
2948: error("connect to %.100s port %d failed: %s",
2949: host, port, strerror(errno));
2950: channel_connect_ctx_free(&cctx);
2951: return NULL;
1.41 markus 2952: }
1.276 djm 2953: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
2954: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
2955: c->connect_ctx = cctx;
2956: return c;
1.41 markus 2957: }
1.99 markus 2958:
1.276 djm 2959: Channel *
2960: channel_connect_by_listen_address(u_short listen_port, char *ctype, char *rname)
1.73 markus 2961: {
2962: int i;
1.99 markus 2963:
1.276 djm 2964: for (i = 0; i < num_permitted_opens; i++) {
1.202 djm 2965: if (permitted_opens[i].host_to_connect != NULL &&
1.276 djm 2966: permitted_opens[i].listen_port == listen_port) {
1.99 markus 2967: return connect_to(
1.73 markus 2968: permitted_opens[i].host_to_connect,
1.276 djm 2969: permitted_opens[i].port_to_connect, ctype, rname);
2970: }
2971: }
1.74 markus 2972: error("WARNING: Server requests forwarding for unknown listen_port %d",
2973: listen_port);
1.276 djm 2974: return NULL;
1.73 markus 2975: }
2976:
1.99 markus 2977: /* Check if connecting to that port is permitted and connect. */
1.276 djm 2978: Channel *
2979: channel_connect_to(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 2980: {
1.257 dtucker 2981: int i, permit, permit_adm = 1;
1.99 markus 2982:
2983: permit = all_opens_permitted;
2984: if (!permit) {
2985: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2986: if (permitted_opens[i].host_to_connect != NULL &&
2987: permitted_opens[i].port_to_connect == port &&
1.99 markus 2988: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2989: permit = 1;
1.257 dtucker 2990: }
1.99 markus 2991:
1.257 dtucker 2992: if (num_adm_permitted_opens > 0) {
2993: permit_adm = 0;
2994: for (i = 0; i < num_adm_permitted_opens; i++)
2995: if (permitted_adm_opens[i].host_to_connect != NULL &&
2996: permitted_adm_opens[i].port_to_connect == port &&
2997: strcmp(permitted_adm_opens[i].host_to_connect, host)
2998: == 0)
2999: permit_adm = 1;
1.99 markus 3000: }
1.257 dtucker 3001:
3002: if (!permit || !permit_adm) {
1.188 itojun 3003: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3004: "but the request was denied.", host, port);
1.276 djm 3005: return NULL;
1.99 markus 3006: }
1.276 djm 3007: return connect_to(host, port, ctype, rname);
1.204 djm 3008: }
3009:
3010: void
3011: channel_send_window_changes(void)
3012: {
1.209 avsm 3013: u_int i;
1.204 djm 3014: struct winsize ws;
3015:
3016: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3017: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3018: channels[i]->type != SSH_CHANNEL_OPEN)
3019: continue;
3020: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3021: continue;
3022: channel_request_start(i, "window-change", 0);
1.238 deraadt 3023: packet_put_int((u_int)ws.ws_col);
3024: packet_put_int((u_int)ws.ws_row);
3025: packet_put_int((u_int)ws.ws_xpixel);
3026: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3027: packet_send();
3028: }
1.99 markus 3029: }
3030:
1.121 markus 3031: /* -- X11 forwarding */
1.1 deraadt 3032:
1.27 markus 3033: /*
3034: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3035: * Returns 0 and a suitable display number for the DISPLAY variable
3036: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3037: */
1.141 stevesk 3038: int
1.163 stevesk 3039: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3040: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3041: {
1.149 markus 3042: Channel *nc = NULL;
1.31 markus 3043: int display_number, sock;
3044: u_short port;
1.35 markus 3045: struct addrinfo hints, *ai, *aitop;
3046: char strport[NI_MAXSERV];
3047: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3048:
1.224 markus 3049: if (chanids == NULL)
3050: return -1;
3051:
1.33 markus 3052: for (display_number = x11_display_offset;
1.148 deraadt 3053: display_number < MAX_DISPLAYS;
3054: display_number++) {
1.25 markus 3055: port = 6000 + display_number;
1.35 markus 3056: memset(&hints, 0, sizeof(hints));
3057: hints.ai_family = IPv4or6;
1.163 stevesk 3058: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3059: hints.ai_socktype = SOCK_STREAM;
3060: snprintf(strport, sizeof strport, "%d", port);
3061: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3062: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3063: return -1;
1.25 markus 3064: }
1.35 markus 3065: for (ai = aitop; ai; ai = ai->ai_next) {
3066: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3067: continue;
1.189 markus 3068: sock = socket(ai->ai_family, ai->ai_socktype,
3069: ai->ai_protocol);
1.35 markus 3070: if (sock < 0) {
3071: error("socket: %.100s", strerror(errno));
1.203 markus 3072: freeaddrinfo(aitop);
1.141 stevesk 3073: return -1;
1.35 markus 3074: }
1.226 djm 3075: channel_set_reuseaddr(sock);
1.35 markus 3076: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3077: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3078: close(sock);
1.183 itojun 3079:
1.35 markus 3080: for (n = 0; n < num_socks; n++) {
3081: close(socks[n]);
3082: }
3083: num_socks = 0;
3084: break;
3085: }
3086: socks[num_socks++] = sock;
3087: if (num_socks == NUM_SOCKS)
3088: break;
1.25 markus 3089: }
1.83 stevesk 3090: freeaddrinfo(aitop);
1.35 markus 3091: if (num_socks > 0)
3092: break;
1.25 markus 3093: }
3094: if (display_number >= MAX_DISPLAYS) {
3095: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3096: return -1;
1.25 markus 3097: }
3098: /* Start listening for connections on the socket. */
1.35 markus 3099: for (n = 0; n < num_socks; n++) {
3100: sock = socks[n];
1.199 markus 3101: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3102: error("listen: %.100s", strerror(errno));
3103: close(sock);
1.141 stevesk 3104: return -1;
1.35 markus 3105: }
1.25 markus 3106: }
1.35 markus 3107:
3108: /* Allocate a channel for each socket. */
1.242 djm 3109: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3110: for (n = 0; n < num_socks; n++) {
3111: sock = socks[n];
1.149 markus 3112: nc = channel_new("x11 listener",
1.51 markus 3113: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3114: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3115: 0, "X11 inet listener", 1);
1.167 markus 3116: nc->single_connection = single_connection;
1.224 markus 3117: (*chanids)[n] = nc->self;
1.35 markus 3118: }
1.224 markus 3119: (*chanids)[n] = -1;
1.1 deraadt 3120:
1.141 stevesk 3121: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3122: *display_numberp = display_number;
3123: return (0);
1.1 deraadt 3124: }
3125:
1.127 itojun 3126: static int
1.77 markus 3127: connect_local_xsocket(u_int dnr)
1.1 deraadt 3128: {
1.25 markus 3129: int sock;
3130: struct sockaddr_un addr;
3131:
1.147 stevesk 3132: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3133: if (sock < 0)
3134: error("socket: %.100s", strerror(errno));
3135: memset(&addr, 0, sizeof(addr));
3136: addr.sun_family = AF_UNIX;
3137: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3138: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3139: return sock;
3140: close(sock);
1.25 markus 3141: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3142: return -1;
1.1 deraadt 3143: }
3144:
1.51 markus 3145: int
3146: x11_connect_display(void)
1.1 deraadt 3147: {
1.248 deraadt 3148: u_int display_number;
1.25 markus 3149: const char *display;
1.51 markus 3150: char buf[1024], *cp;
1.35 markus 3151: struct addrinfo hints, *ai, *aitop;
3152: char strport[NI_MAXSERV];
1.248 deraadt 3153: int gaierr, sock = 0;
1.25 markus 3154:
3155: /* Try to open a socket for the local X server. */
3156: display = getenv("DISPLAY");
3157: if (!display) {
3158: error("DISPLAY not set.");
1.51 markus 3159: return -1;
1.25 markus 3160: }
1.27 markus 3161: /*
3162: * Now we decode the value of the DISPLAY variable and make a
3163: * connection to the real X server.
3164: */
3165:
3166: /*
3167: * Check if it is a unix domain socket. Unix domain displays are in
3168: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3169: */
1.25 markus 3170: if (strncmp(display, "unix:", 5) == 0 ||
3171: display[0] == ':') {
3172: /* Connect to the unix domain socket. */
1.248 deraadt 3173: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3174: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3175: display);
1.51 markus 3176: return -1;
1.25 markus 3177: }
3178: /* Create a socket. */
3179: sock = connect_local_xsocket(display_number);
3180: if (sock < 0)
1.51 markus 3181: return -1;
1.25 markus 3182:
3183: /* OK, we now have a connection to the display. */
1.51 markus 3184: return sock;
1.25 markus 3185: }
1.27 markus 3186: /*
3187: * Connect to an inet socket. The DISPLAY value is supposedly
3188: * hostname:d[.s], where hostname may also be numeric IP address.
3189: */
1.145 stevesk 3190: strlcpy(buf, display, sizeof(buf));
1.25 markus 3191: cp = strchr(buf, ':');
3192: if (!cp) {
3193: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3194: return -1;
1.25 markus 3195: }
3196: *cp = 0;
1.27 markus 3197: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 3198: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 3199: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3200: display);
1.51 markus 3201: return -1;
1.25 markus 3202: }
1.35 markus 3203:
3204: /* Look up the host address */
3205: memset(&hints, 0, sizeof(hints));
3206: hints.ai_family = IPv4or6;
3207: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 3208: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 3209: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3210: error("%.100s: unknown host. (%s)", buf,
3211: ssh_gai_strerror(gaierr));
1.51 markus 3212: return -1;
1.25 markus 3213: }
1.35 markus 3214: for (ai = aitop; ai; ai = ai->ai_next) {
3215: /* Create a socket. */
1.189 markus 3216: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3217: if (sock < 0) {
1.194 markus 3218: debug2("socket: %.100s", strerror(errno));
1.41 markus 3219: continue;
3220: }
3221: /* Connect it to the display. */
3222: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 3223: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 3224: 6000 + display_number, strerror(errno));
3225: close(sock);
3226: continue;
3227: }
3228: /* Success */
3229: break;
1.35 markus 3230: }
3231: freeaddrinfo(aitop);
3232: if (!ai) {
1.248 deraadt 3233: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3234: strerror(errno));
1.51 markus 3235: return -1;
1.25 markus 3236: }
1.162 stevesk 3237: set_nodelay(sock);
1.51 markus 3238: return sock;
3239: }
3240:
3241: /*
3242: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3243: * the remote channel number. We should do whatever we want, and respond
3244: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3245: */
3246:
1.259 stevesk 3247: /* ARGSUSED */
1.51 markus 3248: void
1.154 markus 3249: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3250: {
1.113 markus 3251: Channel *c = NULL;
3252: int remote_id, sock = 0;
1.51 markus 3253: char *remote_host;
1.25 markus 3254:
1.113 markus 3255: debug("Received X11 open request.");
1.51 markus 3256:
1.113 markus 3257: remote_id = packet_get_int();
1.121 markus 3258:
3259: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3260: remote_host = packet_get_string(NULL);
1.51 markus 3261: } else {
3262: remote_host = xstrdup("unknown (remote did not supply name)");
3263: }
1.152 markus 3264: packet_check_eom();
1.25 markus 3265:
1.51 markus 3266: /* Obtain a connection to the real X display. */
3267: sock = x11_connect_display();
1.113 markus 3268: if (sock != -1) {
3269: /* Allocate a channel for this connection. */
3270: c = channel_new("connected x11 socket",
3271: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3272: remote_host, 1);
1.167 markus 3273: c->remote_id = remote_id;
3274: c->force_drain = 1;
1.113 markus 3275: }
1.190 markus 3276: xfree(remote_host);
1.113 markus 3277: if (c == NULL) {
1.51 markus 3278: /* Send refusal to the remote host. */
3279: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3280: packet_put_int(remote_id);
1.51 markus 3281: } else {
3282: /* Send a confirmation to the remote host. */
3283: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3284: packet_put_int(remote_id);
3285: packet_put_int(c->self);
1.51 markus 3286: }
1.113 markus 3287: packet_send();
1.72 markus 3288: }
3289:
3290: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 3291: /* ARGSUSED */
1.72 markus 3292: void
1.154 markus 3293: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3294: {
3295: int rchan = packet_get_int();
1.180 deraadt 3296:
1.143 deraadt 3297: switch (type) {
1.72 markus 3298: case SSH_SMSG_AGENT_OPEN:
3299: error("Warning: ssh server tried agent forwarding.");
3300: break;
3301: case SSH_SMSG_X11_OPEN:
3302: error("Warning: ssh server tried X11 forwarding.");
3303: break;
3304: default:
1.154 markus 3305: error("deny_input_open: type %d", type);
1.72 markus 3306: break;
3307: }
1.230 stevesk 3308: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3309: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3310: packet_put_int(rchan);
3311: packet_send();
1.1 deraadt 3312: }
3313:
1.27 markus 3314: /*
3315: * Requests forwarding of X11 connections, generates fake authentication
3316: * data, and enables authentication spoofing.
1.121 markus 3317: * This should be called in the client only.
1.27 markus 3318: */
1.49 markus 3319: void
1.215 djm 3320: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.51 markus 3321: const char *proto, const char *data)
1.1 deraadt 3322: {
1.77 markus 3323: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3324: u_int i, value;
1.25 markus 3325: char *new_data;
3326: int screen_number;
3327: const char *cp;
1.207 avsm 3328: u_int32_t rnd = 0;
1.25 markus 3329:
1.220 markus 3330: if (x11_saved_display == NULL)
3331: x11_saved_display = xstrdup(disp);
3332: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3333: error("x11_request_forwarding_with_spoofing: different "
3334: "$DISPLAY already forwarded");
3335: return;
3336: }
3337:
1.266 djm 3338: cp = strchr(disp, ':');
1.25 markus 3339: if (cp)
3340: cp = strchr(cp, '.');
3341: if (cp)
1.245 deraadt 3342: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3343: else
3344: screen_number = 0;
3345:
1.219 djm 3346: if (x11_saved_proto == NULL) {
3347: /* Save protocol name. */
3348: x11_saved_proto = xstrdup(proto);
3349: /*
1.221 djm 3350: * Extract real authentication data and generate fake data
1.219 djm 3351: * of the same length.
3352: */
3353: x11_saved_data = xmalloc(data_len);
3354: x11_fake_data = xmalloc(data_len);
3355: for (i = 0; i < data_len; i++) {
3356: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3357: fatal("x11_request_forwarding: bad "
3358: "authentication data: %.100s", data);
3359: if (i % 4 == 0)
3360: rnd = arc4random();
3361: x11_saved_data[i] = value;
3362: x11_fake_data[i] = rnd & 0xff;
3363: rnd >>= 8;
3364: }
3365: x11_saved_data_len = data_len;
3366: x11_fake_data_len = data_len;
1.25 markus 3367: }
3368:
3369: /* Convert the fake data into hex. */
1.219 djm 3370: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3371:
3372: /* Send the request packet. */
1.51 markus 3373: if (compat20) {
3374: channel_request_start(client_session_id, "x11-req", 0);
3375: packet_put_char(0); /* XXX bool single connection */
3376: } else {
3377: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3378: }
3379: packet_put_cstring(proto);
3380: packet_put_cstring(new_data);
1.25 markus 3381: packet_put_int(screen_number);
3382: packet_send();
3383: packet_write_wait();
3384: xfree(new_data);
1.1 deraadt 3385: }
3386:
1.121 markus 3387:
3388: /* -- agent forwarding */
3389:
1.1 deraadt 3390: /* Sends a message to the server to request authentication fd forwarding. */
3391:
1.49 markus 3392: void
1.142 itojun 3393: auth_request_forwarding(void)
1.1 deraadt 3394: {
1.25 markus 3395: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3396: packet_send();
3397: packet_write_wait();
1.1 deraadt 3398: }
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