Annotation of src/usr.bin/ssh/channels.c, Revision 1.297
1.297 ! reyk 1: /* $OpenBSD: channels.c,v 1.296 2009/05/25 06:48:00 andreas 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:
1.297 ! reyk 161: /* Set the routing domain a.k.a. VRF */
! 162: static int channel_rdomain = -1;
! 163:
1.121 markus 164: /* helper */
1.127 itojun 165: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 166:
1.276 djm 167: /* non-blocking connect helpers */
168: static int connect_next(struct channel_connect *);
169: static void channel_connect_ctx_free(struct channel_connect *);
170:
1.121 markus 171: /* -- channel core */
1.41 markus 172:
173: Channel *
1.229 markus 174: channel_by_id(int id)
1.41 markus 175: {
176: Channel *c;
1.113 markus 177:
1.209 avsm 178: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 179: logit("channel_by_id: %d: bad id", id);
1.41 markus 180: return NULL;
181: }
1.113 markus 182: c = channels[id];
183: if (c == NULL) {
1.229 markus 184: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 185: return NULL;
186: }
187: return c;
1.55 markus 188: }
189:
1.27 markus 190: /*
1.229 markus 191: * Returns the channel if it is allowed to receive protocol messages.
192: * Private channels, like listening sockets, may not receive messages.
193: */
194: Channel *
195: channel_lookup(int id)
196: {
197: Channel *c;
198:
199: if ((c = channel_by_id(id)) == NULL)
200: return (NULL);
201:
1.237 deraadt 202: switch (c->type) {
1.229 markus 203: case SSH_CHANNEL_X11_OPEN:
204: case SSH_CHANNEL_LARVAL:
205: case SSH_CHANNEL_CONNECTING:
206: case SSH_CHANNEL_DYNAMIC:
207: case SSH_CHANNEL_OPENING:
208: case SSH_CHANNEL_OPEN:
209: case SSH_CHANNEL_INPUT_DRAINING:
210: case SSH_CHANNEL_OUTPUT_DRAINING:
211: return (c);
212: }
213: logit("Non-public channel %d, type %d.", id, c->type);
214: return (NULL);
215: }
216:
217: /*
1.55 markus 218: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 219: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 220: */
1.127 itojun 221: static void
1.71 markus 222: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 223: int extusage, int nonblock, int is_tty)
1.1 deraadt 224: {
1.25 markus 225: /* Update the maximum file descriptor value. */
1.84 markus 226: channel_max_fd = MAX(channel_max_fd, rfd);
227: channel_max_fd = MAX(channel_max_fd, wfd);
228: channel_max_fd = MAX(channel_max_fd, efd);
229:
1.27 markus 230: /* XXX set close-on-exec -markus */
1.55 markus 231:
1.52 markus 232: c->rfd = rfd;
233: c->wfd = wfd;
234: c->sock = (rfd == wfd) ? rfd : -1;
1.204 djm 235: c->ctl_fd = -1; /* XXX: set elsewhere */
1.52 markus 236: c->efd = efd;
237: c->extended_usage = extusage;
1.71 markus 238:
1.282 dtucker 239: if ((c->isatty = is_tty) != 0)
1.194 markus 240: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 241:
1.71 markus 242: /* enable nonblocking mode */
243: if (nonblock) {
244: if (rfd != -1)
245: set_nonblock(rfd);
246: if (wfd != -1)
247: set_nonblock(wfd);
248: if (efd != -1)
249: set_nonblock(efd);
250: }
1.52 markus 251: }
252:
253: /*
254: * Allocate a new channel object and set its type and socket. This will cause
255: * remote_name to be freed.
256: */
1.113 markus 257: Channel *
1.52 markus 258: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 259: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 260: {
1.209 avsm 261: int found;
262: u_int i;
1.52 markus 263: Channel *c;
1.25 markus 264:
265: /* Do initial allocation if this is the first call. */
266: if (channels_alloc == 0) {
267: channels_alloc = 10;
1.242 djm 268: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 269: for (i = 0; i < channels_alloc; i++)
1.113 markus 270: channels[i] = NULL;
1.25 markus 271: }
272: /* Try to find a free slot where to put the new channel. */
273: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 274: if (channels[i] == NULL) {
1.25 markus 275: /* Found a free slot. */
1.209 avsm 276: found = (int)i;
1.25 markus 277: break;
278: }
1.209 avsm 279: if (found < 0) {
1.27 markus 280: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 281: found = channels_alloc;
1.179 markus 282: if (channels_alloc > 10000)
283: fatal("channel_new: internal error: channels_alloc %d "
284: "too big.", channels_alloc);
1.243 djm 285: channels = xrealloc(channels, channels_alloc + 10,
286: sizeof(Channel *));
1.195 markus 287: channels_alloc += 10;
1.70 markus 288: debug2("channel: expanding %d", channels_alloc);
1.25 markus 289: for (i = found; i < channels_alloc; i++)
1.113 markus 290: channels[i] = NULL;
1.25 markus 291: }
1.113 markus 292: /* Initialize and return new channel. */
1.242 djm 293: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 294: buffer_init(&c->input);
295: buffer_init(&c->output);
1.41 markus 296: buffer_init(&c->extended);
1.293 djm 297: c->path = NULL;
1.159 markus 298: c->ostate = CHAN_OUTPUT_OPEN;
299: c->istate = CHAN_INPUT_OPEN;
300: c->flags = 0;
1.281 djm 301: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 302: c->self = found;
303: c->type = type;
1.41 markus 304: c->ctype = ctype;
1.51 markus 305: c->local_window = window;
306: c->local_window_max = window;
307: c->local_consumed = 0;
308: c->local_maxpacket = maxpack;
1.25 markus 309: c->remote_id = -1;
1.190 markus 310: c->remote_name = xstrdup(remote_name);
1.41 markus 311: c->remote_window = 0;
312: c->remote_maxpacket = 0;
1.133 markus 313: c->force_drain = 0;
1.149 markus 314: c->single_connection = 0;
1.131 markus 315: c->detach_user = NULL;
1.225 djm 316: c->detach_close = 0;
1.275 djm 317: c->open_confirm = NULL;
318: c->open_confirm_ctx = NULL;
1.65 markus 319: c->input_filter = NULL;
1.231 reyk 320: c->output_filter = NULL;
1.280 djm 321: c->filter_ctx = NULL;
322: c->filter_cleanup = NULL;
1.275 djm 323: TAILQ_INIT(&c->status_confirms);
1.25 markus 324: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 325: return c;
1.1 deraadt 326: }
1.52 markus 327:
1.132 markus 328: static int
329: channel_find_maxfd(void)
330: {
1.209 avsm 331: u_int i;
332: int max = 0;
1.132 markus 333: Channel *c;
334:
335: for (i = 0; i < channels_alloc; i++) {
336: c = channels[i];
337: if (c != NULL) {
338: max = MAX(max, c->rfd);
339: max = MAX(max, c->wfd);
340: max = MAX(max, c->efd);
341: }
342: }
343: return max;
344: }
345:
346: int
347: channel_close_fd(int *fdp)
348: {
349: int ret = 0, fd = *fdp;
350:
351: if (fd != -1) {
352: ret = close(fd);
353: *fdp = -1;
354: if (fd == channel_max_fd)
355: channel_max_fd = channel_find_maxfd();
356: }
357: return ret;
358: }
359:
1.52 markus 360: /* Close all channel fd/socket. */
1.127 itojun 361: static void
1.52 markus 362: channel_close_fds(Channel *c)
363: {
1.204 djm 364: debug3("channel %d: close_fds r %d w %d e %d c %d",
365: c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
1.118 markus 366:
1.132 markus 367: channel_close_fd(&c->sock);
1.204 djm 368: channel_close_fd(&c->ctl_fd);
1.132 markus 369: channel_close_fd(&c->rfd);
370: channel_close_fd(&c->wfd);
371: channel_close_fd(&c->efd);
1.121 markus 372: }
373:
374: /* Free the channel and close its fd/socket. */
375: void
376: channel_free(Channel *c)
377: {
378: char *s;
1.209 avsm 379: u_int i, n;
1.275 djm 380: struct channel_confirm *cc;
1.121 markus 381:
382: for (n = 0, i = 0; i < channels_alloc; i++)
383: if (channels[i])
384: n++;
1.209 avsm 385: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 386: c->remote_name ? c->remote_name : "???", n);
387:
388: s = channel_open_message();
1.194 markus 389: debug3("channel %d: status: %s", c->self, s);
1.121 markus 390: xfree(s);
391:
392: if (c->sock != -1)
393: shutdown(c->sock, SHUT_RDWR);
1.204 djm 394: if (c->ctl_fd != -1)
395: shutdown(c->ctl_fd, SHUT_RDWR);
1.121 markus 396: channel_close_fds(c);
397: buffer_free(&c->input);
398: buffer_free(&c->output);
399: buffer_free(&c->extended);
400: if (c->remote_name) {
401: xfree(c->remote_name);
402: c->remote_name = NULL;
403: }
1.293 djm 404: if (c->path) {
405: xfree(c->path);
406: c->path = NULL;
407: }
1.275 djm 408: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
409: if (cc->abandon_cb != NULL)
410: cc->abandon_cb(c, cc->ctx);
411: TAILQ_REMOVE(&c->status_confirms, cc, entry);
412: bzero(cc, sizeof(*cc));
413: xfree(cc);
414: }
1.280 djm 415: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
416: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 417: channels[c->self] = NULL;
418: xfree(c);
419: }
420:
421: void
1.126 markus 422: channel_free_all(void)
1.121 markus 423: {
1.209 avsm 424: u_int i;
1.121 markus 425:
1.126 markus 426: for (i = 0; i < channels_alloc; i++)
427: if (channels[i] != NULL)
428: channel_free(channels[i]);
1.131 markus 429: }
430:
1.121 markus 431: /*
432: * Closes the sockets/fds of all channels. This is used to close extra file
433: * descriptors after a fork.
434: */
435: void
1.142 itojun 436: channel_close_all(void)
1.121 markus 437: {
1.209 avsm 438: u_int i;
1.121 markus 439:
440: for (i = 0; i < channels_alloc; i++)
441: if (channels[i] != NULL)
442: channel_close_fds(channels[i]);
443: }
444:
445: /*
1.131 markus 446: * Stop listening to channels.
447: */
448: void
449: channel_stop_listening(void)
450: {
1.209 avsm 451: u_int i;
1.131 markus 452: Channel *c;
453:
454: for (i = 0; i < channels_alloc; i++) {
455: c = channels[i];
456: if (c != NULL) {
457: switch (c->type) {
458: case SSH_CHANNEL_AUTH_SOCKET:
459: case SSH_CHANNEL_PORT_LISTENER:
460: case SSH_CHANNEL_RPORT_LISTENER:
461: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 462: channel_close_fd(&c->sock);
1.131 markus 463: channel_free(c);
464: break;
465: }
466: }
467: }
468: }
469:
470: /*
1.121 markus 471: * Returns true if no channel has too much buffered data, and false if one or
472: * more channel is overfull.
473: */
474: int
1.142 itojun 475: channel_not_very_much_buffered_data(void)
1.121 markus 476: {
477: u_int i;
478: Channel *c;
479:
480: for (i = 0; i < channels_alloc; i++) {
481: c = channels[i];
482: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 483: #if 0
484: if (!compat20 &&
485: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 486: debug2("channel %d: big input buffer %d",
1.121 markus 487: c->self, buffer_len(&c->input));
488: return 0;
489: }
1.136 markus 490: #endif
1.121 markus 491: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 492: debug2("channel %d: big output buffer %u > %u",
1.136 markus 493: c->self, buffer_len(&c->output),
494: packet_get_maxsize());
1.121 markus 495: return 0;
496: }
497: }
498: }
499: return 1;
500: }
501:
502: /* Returns true if any channel is still open. */
503: int
1.142 itojun 504: channel_still_open(void)
1.121 markus 505: {
1.209 avsm 506: u_int i;
1.121 markus 507: Channel *c;
508:
509: for (i = 0; i < channels_alloc; i++) {
510: c = channels[i];
511: if (c == NULL)
512: continue;
513: switch (c->type) {
514: case SSH_CHANNEL_X11_LISTENER:
515: case SSH_CHANNEL_PORT_LISTENER:
516: case SSH_CHANNEL_RPORT_LISTENER:
517: case SSH_CHANNEL_CLOSED:
518: case SSH_CHANNEL_AUTH_SOCKET:
519: case SSH_CHANNEL_DYNAMIC:
520: case SSH_CHANNEL_CONNECTING:
521: case SSH_CHANNEL_ZOMBIE:
522: continue;
523: case SSH_CHANNEL_LARVAL:
524: if (!compat20)
525: fatal("cannot happen: SSH_CHANNEL_LARVAL");
526: continue;
527: case SSH_CHANNEL_OPENING:
528: case SSH_CHANNEL_OPEN:
529: case SSH_CHANNEL_X11_OPEN:
530: return 1;
531: case SSH_CHANNEL_INPUT_DRAINING:
532: case SSH_CHANNEL_OUTPUT_DRAINING:
533: if (!compat13)
534: fatal("cannot happen: OUT_DRAIN");
535: return 1;
536: default:
537: fatal("channel_still_open: bad channel type %d", c->type);
538: /* NOTREACHED */
539: }
540: }
541: return 0;
542: }
543:
544: /* Returns the id of an open channel suitable for keepaliving */
545: int
1.142 itojun 546: channel_find_open(void)
1.121 markus 547: {
1.209 avsm 548: u_int i;
1.121 markus 549: Channel *c;
550:
551: for (i = 0; i < channels_alloc; i++) {
552: c = channels[i];
1.206 djm 553: if (c == NULL || c->remote_id < 0)
1.121 markus 554: continue;
555: switch (c->type) {
556: case SSH_CHANNEL_CLOSED:
557: case SSH_CHANNEL_DYNAMIC:
558: case SSH_CHANNEL_X11_LISTENER:
559: case SSH_CHANNEL_PORT_LISTENER:
560: case SSH_CHANNEL_RPORT_LISTENER:
561: case SSH_CHANNEL_OPENING:
562: case SSH_CHANNEL_CONNECTING:
563: case SSH_CHANNEL_ZOMBIE:
564: continue;
565: case SSH_CHANNEL_LARVAL:
566: case SSH_CHANNEL_AUTH_SOCKET:
567: case SSH_CHANNEL_OPEN:
568: case SSH_CHANNEL_X11_OPEN:
569: return i;
570: case SSH_CHANNEL_INPUT_DRAINING:
571: case SSH_CHANNEL_OUTPUT_DRAINING:
572: if (!compat13)
573: fatal("cannot happen: OUT_DRAIN");
574: return i;
575: default:
576: fatal("channel_find_open: bad channel type %d", c->type);
577: /* NOTREACHED */
578: }
579: }
580: return -1;
581: }
582:
583:
584: /*
585: * Returns a message describing the currently open forwarded connections,
586: * suitable for sending to the client. The message contains crlf pairs for
587: * newlines.
588: */
589: char *
1.142 itojun 590: channel_open_message(void)
1.121 markus 591: {
592: Buffer buffer;
593: Channel *c;
594: char buf[1024], *cp;
1.209 avsm 595: u_int i;
1.121 markus 596:
597: buffer_init(&buffer);
598: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
599: buffer_append(&buffer, buf, strlen(buf));
600: for (i = 0; i < channels_alloc; i++) {
601: c = channels[i];
602: if (c == NULL)
603: continue;
604: switch (c->type) {
605: case SSH_CHANNEL_X11_LISTENER:
606: case SSH_CHANNEL_PORT_LISTENER:
607: case SSH_CHANNEL_RPORT_LISTENER:
608: case SSH_CHANNEL_CLOSED:
609: case SSH_CHANNEL_AUTH_SOCKET:
610: case SSH_CHANNEL_ZOMBIE:
611: continue;
612: case SSH_CHANNEL_LARVAL:
613: case SSH_CHANNEL_OPENING:
614: case SSH_CHANNEL_CONNECTING:
615: case SSH_CHANNEL_DYNAMIC:
616: case SSH_CHANNEL_OPEN:
617: case SSH_CHANNEL_X11_OPEN:
618: case SSH_CHANNEL_INPUT_DRAINING:
619: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 620: snprintf(buf, sizeof buf,
621: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
1.121 markus 622: c->self, c->remote_name,
623: c->type, c->remote_id,
624: c->istate, buffer_len(&c->input),
625: c->ostate, buffer_len(&c->output),
1.204 djm 626: c->rfd, c->wfd, c->ctl_fd);
1.121 markus 627: buffer_append(&buffer, buf, strlen(buf));
628: continue;
629: default:
630: fatal("channel_open_message: bad channel type %d", c->type);
631: /* NOTREACHED */
632: }
633: }
634: buffer_append(&buffer, "\0", 1);
635: cp = xstrdup(buffer_ptr(&buffer));
636: buffer_free(&buffer);
637: return cp;
638: }
639:
640: void
641: channel_send_open(int id)
642: {
643: Channel *c = channel_lookup(id);
1.180 deraadt 644:
1.121 markus 645: if (c == NULL) {
1.188 itojun 646: logit("channel_send_open: %d: bad id", id);
1.121 markus 647: return;
648: }
1.184 markus 649: debug2("channel %d: send open", id);
1.121 markus 650: packet_start(SSH2_MSG_CHANNEL_OPEN);
651: packet_put_cstring(c->ctype);
652: packet_put_int(c->self);
653: packet_put_int(c->local_window);
654: packet_put_int(c->local_maxpacket);
655: packet_send();
656: }
657:
658: void
1.184 markus 659: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 660: {
1.184 markus 661: Channel *c = channel_lookup(id);
1.180 deraadt 662:
1.121 markus 663: if (c == NULL) {
1.188 itojun 664: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 665: return;
666: }
1.204 djm 667: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 668: packet_start(SSH2_MSG_CHANNEL_REQUEST);
669: packet_put_int(c->remote_id);
670: packet_put_cstring(service);
671: packet_put_char(wantconfirm);
672: }
1.241 deraadt 673:
1.121 markus 674: void
1.275 djm 675: channel_register_status_confirm(int id, channel_confirm_cb *cb,
676: channel_confirm_abandon_cb *abandon_cb, void *ctx)
677: {
678: struct channel_confirm *cc;
679: Channel *c;
680:
681: if ((c = channel_lookup(id)) == NULL)
682: fatal("channel_register_expect: %d: bad id", id);
683:
684: cc = xmalloc(sizeof(*cc));
685: cc->cb = cb;
686: cc->abandon_cb = abandon_cb;
687: cc->ctx = ctx;
688: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
689: }
690:
691: void
692: channel_register_open_confirm(int id, channel_callback_fn *fn, void *ctx)
1.121 markus 693: {
694: Channel *c = channel_lookup(id);
1.180 deraadt 695:
1.121 markus 696: if (c == NULL) {
1.287 stevesk 697: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 698: return;
699: }
1.275 djm 700: c->open_confirm = fn;
701: c->open_confirm_ctx = ctx;
1.121 markus 702: }
1.241 deraadt 703:
1.121 markus 704: void
1.225 djm 705: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 706: {
1.229 markus 707: Channel *c = channel_by_id(id);
1.180 deraadt 708:
1.121 markus 709: if (c == NULL) {
1.188 itojun 710: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 711: return;
712: }
1.131 markus 713: c->detach_user = fn;
1.225 djm 714: c->detach_close = do_close;
1.121 markus 715: }
1.241 deraadt 716:
1.121 markus 717: void
718: channel_cancel_cleanup(int id)
719: {
1.229 markus 720: Channel *c = channel_by_id(id);
1.180 deraadt 721:
1.121 markus 722: if (c == NULL) {
1.188 itojun 723: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 724: return;
1.52 markus 725: }
1.131 markus 726: c->detach_user = NULL;
1.225 djm 727: c->detach_close = 0;
1.121 markus 728: }
1.241 deraadt 729:
1.121 markus 730: void
1.231 reyk 731: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 732: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 733: {
734: Channel *c = channel_lookup(id);
1.180 deraadt 735:
1.121 markus 736: if (c == NULL) {
1.188 itojun 737: logit("channel_register_filter: %d: bad id", id);
1.121 markus 738: return;
1.52 markus 739: }
1.231 reyk 740: c->input_filter = ifn;
741: c->output_filter = ofn;
1.279 djm 742: c->filter_ctx = ctx;
1.280 djm 743: c->filter_cleanup = cfn;
1.52 markus 744: }
745:
1.49 markus 746: void
1.121 markus 747: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 748: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 749: {
1.121 markus 750: Channel *c = channel_lookup(id);
1.180 deraadt 751:
1.121 markus 752: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
753: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 754: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 755: c->type = SSH_CHANNEL_OPEN;
1.168 markus 756: c->local_window = c->local_window_max = window_max;
1.121 markus 757: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
758: packet_put_int(c->remote_id);
759: packet_put_int(c->local_window);
760: packet_send();
1.1 deraadt 761: }
762:
1.27 markus 763: /*
1.41 markus 764: * 'channel_pre*' are called just before select() to add any bits relevant to
765: * channels in the select bitmasks.
766: */
767: /*
768: * 'channel_post*': perform any appropriate operations for channels which
769: * have events pending.
1.27 markus 770: */
1.237 deraadt 771: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 772: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
773: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
774:
1.259 stevesk 775: /* ARGSUSED */
1.127 itojun 776: static void
1.237 deraadt 777: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 778: {
779: FD_SET(c->sock, readset);
780: }
781:
1.259 stevesk 782: /* ARGSUSED */
1.127 itojun 783: static void
1.237 deraadt 784: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 785: {
786: debug3("channel %d: waiting for connection", c->self);
787: FD_SET(c->sock, writeset);
788: }
789:
1.127 itojun 790: static void
1.237 deraadt 791: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 792: {
793: if (buffer_len(&c->input) < packet_get_maxsize())
794: FD_SET(c->sock, readset);
795: if (buffer_len(&c->output) > 0)
796: FD_SET(c->sock, writeset);
797: }
1.1 deraadt 798:
1.127 itojun 799: static void
1.237 deraadt 800: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 801: {
1.157 markus 802: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 803:
1.44 markus 804: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 805: limit > 0 &&
1.250 djm 806: buffer_len(&c->input) < limit &&
807: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 808: FD_SET(c->rfd, readset);
809: if (c->ostate == CHAN_OUTPUT_OPEN ||
810: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
811: if (buffer_len(&c->output) > 0) {
812: FD_SET(c->wfd, writeset);
813: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 814: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 815: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
816: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 817: else
818: chan_obuf_empty(c);
1.44 markus 819: }
820: }
821: /** XXX check close conditions, too */
1.277 markus 822: if (compat20 && c->efd != -1 &&
823: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 824: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
825: buffer_len(&c->extended) > 0)
826: FD_SET(c->efd, writeset);
1.172 markus 827: else if (!(c->flags & CHAN_EOF_SENT) &&
828: c->extended_usage == CHAN_EXTENDED_READ &&
1.44 markus 829: buffer_len(&c->extended) < c->remote_window)
830: FD_SET(c->efd, readset);
831: }
1.204 djm 832: /* XXX: What about efd? races? */
1.208 deraadt 833: if (compat20 && c->ctl_fd != -1 &&
1.204 djm 834: c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
835: FD_SET(c->ctl_fd, readset);
1.44 markus 836: }
837:
1.259 stevesk 838: /* ARGSUSED */
1.127 itojun 839: static void
1.237 deraadt 840: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 841: {
842: if (buffer_len(&c->input) == 0) {
843: packet_start(SSH_MSG_CHANNEL_CLOSE);
844: packet_put_int(c->remote_id);
845: packet_send();
846: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 847: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 848: }
849: }
850:
1.259 stevesk 851: /* ARGSUSED */
1.127 itojun 852: static void
1.237 deraadt 853: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 854: {
855: if (buffer_len(&c->output) == 0)
1.113 markus 856: chan_mark_dead(c);
1.49 markus 857: else
1.41 markus 858: FD_SET(c->sock, writeset);
859: }
860:
861: /*
862: * This is a special state for X11 authentication spoofing. An opened X11
863: * connection (when authentication spoofing is being done) remains in this
864: * state until the first packet has been completely read. The authentication
865: * data in that packet is then substituted by the real data if it matches the
866: * fake data, and the channel is put into normal mode.
1.51 markus 867: * XXX All this happens at the client side.
1.121 markus 868: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 869: */
1.127 itojun 870: static int
1.121 markus 871: x11_open_helper(Buffer *b)
1.1 deraadt 872: {
1.77 markus 873: u_char *ucp;
874: u_int proto_len, data_len;
1.25 markus 875:
1.41 markus 876: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 877: if (buffer_len(b) < 12)
1.41 markus 878: return 0;
879:
880: /* Parse the lengths of variable-length fields. */
1.155 stevesk 881: ucp = buffer_ptr(b);
1.41 markus 882: if (ucp[0] == 0x42) { /* Byte order MSB first. */
883: proto_len = 256 * ucp[6] + ucp[7];
884: data_len = 256 * ucp[8] + ucp[9];
885: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
886: proto_len = ucp[6] + 256 * ucp[7];
887: data_len = ucp[8] + 256 * ucp[9];
888: } else {
1.194 markus 889: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 890: ucp[0]);
1.41 markus 891: return -1;
892: }
893:
894: /* Check if the whole packet is in buffer. */
1.121 markus 895: if (buffer_len(b) <
1.41 markus 896: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
897: return 0;
898:
899: /* Check if authentication protocol matches. */
900: if (proto_len != strlen(x11_saved_proto) ||
901: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 902: debug2("X11 connection uses different authentication protocol.");
1.41 markus 903: return -1;
904: }
905: /* Check if authentication data matches our fake data. */
906: if (data_len != x11_fake_data_len ||
907: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
908: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 909: debug2("X11 auth data does not match fake data.");
1.41 markus 910: return -1;
911: }
912: /* Check fake data length */
913: if (x11_fake_data_len != x11_saved_data_len) {
914: error("X11 fake_data_len %d != saved_data_len %d",
915: x11_fake_data_len, x11_saved_data_len);
916: return -1;
917: }
918: /*
919: * Received authentication protocol and data match
920: * our fake data. Substitute the fake data with real
921: * data.
922: */
923: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
924: x11_saved_data, x11_saved_data_len);
925: return 1;
926: }
927:
1.127 itojun 928: static void
1.237 deraadt 929: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 930: {
1.121 markus 931: int ret = x11_open_helper(&c->output);
1.180 deraadt 932:
1.41 markus 933: if (ret == 1) {
934: /* Start normal processing for the channel. */
935: c->type = SSH_CHANNEL_OPEN;
1.47 markus 936: channel_pre_open_13(c, readset, writeset);
1.41 markus 937: } else if (ret == -1) {
938: /*
939: * We have received an X11 connection that has bad
940: * authentication information.
941: */
1.188 itojun 942: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 943: buffer_clear(&c->input);
944: buffer_clear(&c->output);
1.132 markus 945: channel_close_fd(&c->sock);
1.41 markus 946: c->sock = -1;
947: c->type = SSH_CHANNEL_CLOSED;
948: packet_start(SSH_MSG_CHANNEL_CLOSE);
949: packet_put_int(c->remote_id);
950: packet_send();
951: }
952: }
1.25 markus 953:
1.127 itojun 954: static void
1.237 deraadt 955: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 956: {
1.121 markus 957: int ret = x11_open_helper(&c->output);
1.133 markus 958:
959: /* c->force_drain = 1; */
960:
1.41 markus 961: if (ret == 1) {
962: c->type = SSH_CHANNEL_OPEN;
1.157 markus 963: channel_pre_open(c, readset, writeset);
1.41 markus 964: } else if (ret == -1) {
1.188 itojun 965: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 966: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 967: chan_read_failed(c);
968: buffer_clear(&c->input);
969: chan_ibuf_empty(c);
970: buffer_clear(&c->output);
971: /* for proto v1, the peer will send an IEOF */
972: if (compat20)
973: chan_write_failed(c);
974: else
975: c->type = SSH_CHANNEL_OPEN;
1.194 markus 976: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 977: }
978: }
1.25 markus 979:
1.104 markus 980: /* try to decode a socks4 header */
1.259 stevesk 981: /* ARGSUSED */
1.127 itojun 982: static int
1.237 deraadt 983: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 984: {
1.181 markus 985: char *p, *host;
1.292 djm 986: u_int len, have, i, found, need;
1.148 deraadt 987: char username[256];
1.103 markus 988: struct {
989: u_int8_t version;
990: u_int8_t command;
991: u_int16_t dest_port;
1.104 markus 992: struct in_addr dest_addr;
1.103 markus 993: } s4_req, s4_rsp;
994:
1.104 markus 995: debug2("channel %d: decode socks4", c->self);
1.109 markus 996:
997: have = buffer_len(&c->input);
998: len = sizeof(s4_req);
999: if (have < len)
1000: return 0;
1001: p = buffer_ptr(&c->input);
1.292 djm 1002:
1003: need = 1;
1004: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1005: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1006: debug2("channel %d: socks4a request", c->self);
1007: /* ... and needs an extra string (the hostname) */
1008: need = 2;
1009: }
1010: /* Check for terminating NUL on the string(s) */
1.109 markus 1011: for (found = 0, i = len; i < have; i++) {
1012: if (p[i] == '\0') {
1.292 djm 1013: found++;
1014: if (found == need)
1015: break;
1.109 markus 1016: }
1017: if (i > 1024) {
1018: /* the peer is probably sending garbage */
1019: debug("channel %d: decode socks4: too long",
1020: c->self);
1021: return -1;
1022: }
1023: }
1.292 djm 1024: if (found < need)
1.109 markus 1025: return 0;
1.103 markus 1026: buffer_get(&c->input, (char *)&s4_req.version, 1);
1027: buffer_get(&c->input, (char *)&s4_req.command, 1);
1028: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1029: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1030: have = buffer_len(&c->input);
1.103 markus 1031: p = buffer_ptr(&c->input);
1032: len = strlen(p);
1.106 markus 1033: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1034: len++; /* trailing '\0' */
1.103 markus 1035: if (len > have)
1.104 markus 1036: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1037: c->self, len, have);
1038: strlcpy(username, p, sizeof(username));
1039: buffer_consume(&c->input, len);
1040:
1.293 djm 1041: if (c->path != NULL) {
1042: xfree(c->path);
1043: c->path = NULL;
1044: }
1.292 djm 1045: if (need == 1) { /* SOCKS4: one string */
1046: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1047: c->path = xstrdup(host);
1.292 djm 1048: } else { /* SOCKS4A: two strings */
1049: have = buffer_len(&c->input);
1050: p = buffer_ptr(&c->input);
1051: len = strlen(p);
1052: debug2("channel %d: decode socks4a: host %s/%d",
1053: c->self, p, len);
1054: len++; /* trailing '\0' */
1055: if (len > have)
1056: fatal("channel %d: decode socks4a: len %d > have %d",
1057: c->self, len, have);
1.293 djm 1058: if (len > NI_MAXHOST) {
1.292 djm 1059: error("channel %d: hostname \"%.100s\" too long",
1060: c->self, p);
1061: return -1;
1062: }
1.293 djm 1063: c->path = xstrdup(p);
1.292 djm 1064: buffer_consume(&c->input, len);
1065: }
1.103 markus 1066: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1067:
1.194 markus 1068: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1069: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1070:
1.104 markus 1071: if (s4_req.command != 1) {
1.292 djm 1072: debug("channel %d: cannot handle: %s cn %d",
1073: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1074: return -1;
1.103 markus 1075: }
1.104 markus 1076: s4_rsp.version = 0; /* vn: 0 for reply */
1077: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1078: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1079: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1080: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1081: return 1;
1082: }
1083:
1.193 markus 1084: /* try to decode a socks5 header */
1085: #define SSH_SOCKS5_AUTHDONE 0x1000
1086: #define SSH_SOCKS5_NOAUTH 0x00
1087: #define SSH_SOCKS5_IPV4 0x01
1088: #define SSH_SOCKS5_DOMAIN 0x03
1089: #define SSH_SOCKS5_IPV6 0x04
1090: #define SSH_SOCKS5_CONNECT 0x01
1091: #define SSH_SOCKS5_SUCCESS 0x00
1092:
1.259 stevesk 1093: /* ARGSUSED */
1.193 markus 1094: static int
1.237 deraadt 1095: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1096: {
1097: struct {
1098: u_int8_t version;
1099: u_int8_t command;
1100: u_int8_t reserved;
1101: u_int8_t atyp;
1102: } s5_req, s5_rsp;
1103: u_int16_t dest_port;
1.293 djm 1104: u_char *p, dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.252 djm 1105: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1106:
1107: debug2("channel %d: decode socks5", c->self);
1108: p = buffer_ptr(&c->input);
1109: if (p[0] != 0x05)
1110: return -1;
1111: have = buffer_len(&c->input);
1112: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1113: /* format: ver | nmethods | methods */
1.198 djm 1114: if (have < 2)
1.193 markus 1115: return 0;
1116: nmethods = p[1];
1117: if (have < nmethods + 2)
1118: return 0;
1119: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1120: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1121: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1122: found = 1;
1123: break;
1124: }
1125: }
1126: if (!found) {
1127: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1128: c->self);
1129: return -1;
1130: }
1131: buffer_consume(&c->input, nmethods + 2);
1132: buffer_put_char(&c->output, 0x05); /* version */
1133: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1134: FD_SET(c->sock, writeset);
1135: c->flags |= SSH_SOCKS5_AUTHDONE;
1136: debug2("channel %d: socks5 auth done", c->self);
1137: return 0; /* need more */
1138: }
1139: debug2("channel %d: socks5 post auth", c->self);
1140: if (have < sizeof(s5_req)+1)
1141: return 0; /* need more */
1.247 deraadt 1142: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1143: if (s5_req.version != 0x05 ||
1144: s5_req.command != SSH_SOCKS5_CONNECT ||
1145: s5_req.reserved != 0x00) {
1.194 markus 1146: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1147: return -1;
1148: }
1.213 deraadt 1149: switch (s5_req.atyp){
1.193 markus 1150: case SSH_SOCKS5_IPV4:
1151: addrlen = 4;
1152: af = AF_INET;
1153: break;
1154: case SSH_SOCKS5_DOMAIN:
1155: addrlen = p[sizeof(s5_req)];
1156: af = -1;
1157: break;
1158: case SSH_SOCKS5_IPV6:
1159: addrlen = 16;
1160: af = AF_INET6;
1161: break;
1162: default:
1.194 markus 1163: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1164: return -1;
1165: }
1.252 djm 1166: need = sizeof(s5_req) + addrlen + 2;
1167: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1168: need++;
1169: if (have < need)
1.193 markus 1170: return 0;
1171: buffer_consume(&c->input, sizeof(s5_req));
1172: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1173: buffer_consume(&c->input, 1); /* host string length */
1174: buffer_get(&c->input, (char *)&dest_addr, addrlen);
1175: buffer_get(&c->input, (char *)&dest_port, 2);
1176: dest_addr[addrlen] = '\0';
1.293 djm 1177: if (c->path != NULL) {
1178: xfree(c->path);
1179: c->path = NULL;
1180: }
1181: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1182: if (addrlen >= NI_MAXHOST) {
1.293 djm 1183: error("channel %d: dynamic request: socks5 hostname "
1184: "\"%.100s\" too long", c->self, dest_addr);
1185: return -1;
1186: }
1187: c->path = xstrdup(dest_addr);
1188: } else {
1189: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1190: return -1;
1191: c->path = xstrdup(ntop);
1192: }
1.193 markus 1193: c->host_port = ntohs(dest_port);
1.198 djm 1194:
1.194 markus 1195: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1196: c->self, c->path, c->host_port, s5_req.command);
1197:
1198: s5_rsp.version = 0x05;
1199: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1200: s5_rsp.reserved = 0; /* ignored */
1201: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1202: ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1203: dest_port = 0; /* ignored */
1204:
1.246 deraadt 1205: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1206: buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1207: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1208: return 1;
1209: }
1210:
1.104 markus 1211: /* dynamic port forwarding */
1.127 itojun 1212: static void
1.237 deraadt 1213: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1214: {
1215: u_char *p;
1.217 djm 1216: u_int have;
1217: int ret;
1.103 markus 1218:
1.104 markus 1219: have = buffer_len(&c->input);
1.137 markus 1220: c->delayed = 0;
1.104 markus 1221: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1222: /* buffer_dump(&c->input); */
1.104 markus 1223: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1224: if (have < 3) {
1.104 markus 1225: /* need more */
1226: FD_SET(c->sock, readset);
1227: return;
1228: }
1229: /* try to guess the protocol */
1230: p = buffer_ptr(&c->input);
1231: switch (p[0]) {
1232: case 0x04:
1233: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1234: break;
1235: case 0x05:
1236: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1237: break;
1238: default:
1239: ret = -1;
1240: break;
1241: }
1242: if (ret < 0) {
1.113 markus 1243: chan_mark_dead(c);
1.104 markus 1244: } else if (ret == 0) {
1245: debug2("channel %d: pre_dynamic: need more", c->self);
1246: /* need more */
1247: FD_SET(c->sock, readset);
1248: } else {
1249: /* switch to the next state */
1250: c->type = SSH_CHANNEL_OPENING;
1251: port_open_helper(c, "direct-tcpip");
1252: }
1.103 markus 1253: }
1254:
1.41 markus 1255: /* This is our fake X11 server socket. */
1.259 stevesk 1256: /* ARGSUSED */
1.127 itojun 1257: static void
1.237 deraadt 1258: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1259: {
1.113 markus 1260: Channel *nc;
1.285 djm 1261: struct sockaddr_storage addr;
1.162 stevesk 1262: int newsock;
1.41 markus 1263: socklen_t addrlen;
1.85 markus 1264: char buf[16384], *remote_ipaddr;
1.51 markus 1265: int remote_port;
1.25 markus 1266:
1.41 markus 1267: if (FD_ISSET(c->sock, readset)) {
1268: debug("X11 connection requested.");
1269: addrlen = sizeof(addr);
1.285 djm 1270: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1271: if (c->single_connection) {
1.194 markus 1272: debug2("single_connection: closing X11 listener.");
1.149 markus 1273: channel_close_fd(&c->sock);
1274: chan_mark_dead(c);
1275: }
1.41 markus 1276: if (newsock < 0) {
1277: error("accept: %.100s", strerror(errno));
1278: return;
1279: }
1.162 stevesk 1280: set_nodelay(newsock);
1.85 markus 1281: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1282: remote_port = get_peer_port(newsock);
1.41 markus 1283: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1284: remote_ipaddr, remote_port);
1.51 markus 1285:
1.113 markus 1286: nc = channel_new("accepted x11 socket",
1.51 markus 1287: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1288: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1289: if (compat20) {
1290: packet_start(SSH2_MSG_CHANNEL_OPEN);
1291: packet_put_cstring("x11");
1.113 markus 1292: packet_put_int(nc->self);
1.149 markus 1293: packet_put_int(nc->local_window_max);
1294: packet_put_int(nc->local_maxpacket);
1.85 markus 1295: /* originator ipaddr and port */
1296: packet_put_cstring(remote_ipaddr);
1.57 markus 1297: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1298: debug2("ssh2 x11 bug compat mode");
1.57 markus 1299: } else {
1300: packet_put_int(remote_port);
1301: }
1.51 markus 1302: packet_send();
1303: } else {
1304: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1305: packet_put_int(nc->self);
1.121 markus 1306: if (packet_get_protocol_flags() &
1307: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1308: packet_put_cstring(buf);
1.51 markus 1309: packet_send();
1310: }
1.85 markus 1311: xfree(remote_ipaddr);
1.41 markus 1312: }
1313: }
1.25 markus 1314:
1.127 itojun 1315: static void
1.103 markus 1316: port_open_helper(Channel *c, char *rtype)
1317: {
1318: int direct;
1319: char buf[1024];
1320: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1321: int remote_port = get_peer_port(c->sock);
1.103 markus 1322:
1323: direct = (strcmp(rtype, "direct-tcpip") == 0);
1324:
1325: snprintf(buf, sizeof buf,
1326: "%s: listening port %d for %.100s port %d, "
1327: "connect from %.200s port %d",
1328: rtype, c->listening_port, c->path, c->host_port,
1329: remote_ipaddr, remote_port);
1330:
1331: xfree(c->remote_name);
1332: c->remote_name = xstrdup(buf);
1333:
1334: if (compat20) {
1335: packet_start(SSH2_MSG_CHANNEL_OPEN);
1336: packet_put_cstring(rtype);
1337: packet_put_int(c->self);
1338: packet_put_int(c->local_window_max);
1339: packet_put_int(c->local_maxpacket);
1340: if (direct) {
1341: /* target host, port */
1342: packet_put_cstring(c->path);
1343: packet_put_int(c->host_port);
1344: } else {
1345: /* listen address, port */
1346: packet_put_cstring(c->path);
1347: packet_put_int(c->listening_port);
1348: }
1349: /* originator host and port */
1350: packet_put_cstring(remote_ipaddr);
1.216 markus 1351: packet_put_int((u_int)remote_port);
1.103 markus 1352: packet_send();
1353: } else {
1354: packet_start(SSH_MSG_PORT_OPEN);
1355: packet_put_int(c->self);
1356: packet_put_cstring(c->path);
1357: packet_put_int(c->host_port);
1.121 markus 1358: if (packet_get_protocol_flags() &
1359: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1360: packet_put_cstring(c->remote_name);
1361: packet_send();
1362: }
1363: xfree(remote_ipaddr);
1364: }
1365:
1.226 djm 1366: static void
1367: channel_set_reuseaddr(int fd)
1368: {
1369: int on = 1;
1370:
1371: /*
1372: * Set socket options.
1373: * Allow local port reuse in TIME_WAIT.
1374: */
1375: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1376: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1377: }
1378:
1.41 markus 1379: /*
1380: * This socket is listening for connections to a forwarded TCP/IP port.
1381: */
1.259 stevesk 1382: /* ARGSUSED */
1.127 itojun 1383: static void
1.237 deraadt 1384: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1385: {
1.103 markus 1386: Channel *nc;
1.285 djm 1387: struct sockaddr_storage addr;
1.113 markus 1388: int newsock, nextstate;
1.41 markus 1389: socklen_t addrlen;
1.103 markus 1390: char *rtype;
1.73 markus 1391:
1.41 markus 1392: if (FD_ISSET(c->sock, readset)) {
1393: debug("Connection to port %d forwarding "
1394: "to %.100s port %d requested.",
1395: c->listening_port, c->path, c->host_port);
1.103 markus 1396:
1.137 markus 1397: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1398: nextstate = SSH_CHANNEL_OPENING;
1399: rtype = "forwarded-tcpip";
1400: } else {
1401: if (c->host_port == 0) {
1402: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1403: rtype = "dynamic-tcpip";
1.137 markus 1404: } else {
1405: nextstate = SSH_CHANNEL_OPENING;
1406: rtype = "direct-tcpip";
1407: }
1408: }
1.103 markus 1409:
1.41 markus 1410: addrlen = sizeof(addr);
1.285 djm 1411: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1412: if (newsock < 0) {
1413: error("accept: %.100s", strerror(errno));
1414: return;
1415: }
1.169 stevesk 1416: set_nodelay(newsock);
1.190 markus 1417: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1418: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1419: nc->listening_port = c->listening_port;
1420: nc->host_port = c->host_port;
1.293 djm 1421: if (c->path != NULL)
1422: nc->path = xstrdup(c->path);
1.103 markus 1423:
1.137 markus 1424: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1425: /*
1426: * do not call the channel_post handler until
1427: * this flag has been reset by a pre-handler.
1428: * otherwise the FD_ISSET calls might overflow
1429: */
1430: nc->delayed = 1;
1431: } else {
1.103 markus 1432: port_open_helper(nc, rtype);
1.137 markus 1433: }
1.41 markus 1434: }
1435: }
1.25 markus 1436:
1.41 markus 1437: /*
1438: * This is the authentication agent socket listening for connections from
1439: * clients.
1440: */
1.259 stevesk 1441: /* ARGSUSED */
1.127 itojun 1442: static void
1.237 deraadt 1443: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1444: {
1.113 markus 1445: Channel *nc;
1446: int newsock;
1.285 djm 1447: struct sockaddr_storage addr;
1.41 markus 1448: socklen_t addrlen;
1.25 markus 1449:
1.41 markus 1450: if (FD_ISSET(c->sock, readset)) {
1451: addrlen = sizeof(addr);
1.285 djm 1452: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1453: if (newsock < 0) {
1454: error("accept from auth socket: %.100s", strerror(errno));
1455: return;
1456: }
1.113 markus 1457: nc = channel_new("accepted auth socket",
1.73 markus 1458: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1459: c->local_window_max, c->local_maxpacket,
1.190 markus 1460: 0, "accepted auth socket", 1);
1.73 markus 1461: if (compat20) {
1462: packet_start(SSH2_MSG_CHANNEL_OPEN);
1463: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1464: packet_put_int(nc->self);
1.73 markus 1465: packet_put_int(c->local_window_max);
1466: packet_put_int(c->local_maxpacket);
1467: } else {
1468: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1469: packet_put_int(nc->self);
1.73 markus 1470: }
1.41 markus 1471: packet_send();
1472: }
1473: }
1.25 markus 1474:
1.259 stevesk 1475: /* ARGSUSED */
1.127 itojun 1476: static void
1.237 deraadt 1477: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1478: {
1.276 djm 1479: int err = 0, sock;
1.129 stevesk 1480: socklen_t sz = sizeof(err);
1.114 markus 1481:
1.75 markus 1482: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1483: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1484: err = errno;
1485: error("getsockopt SO_ERROR failed");
1486: }
1487: if (err == 0) {
1.276 djm 1488: debug("channel %d: connected to %s port %d",
1489: c->self, c->connect_ctx.host, c->connect_ctx.port);
1490: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1491: c->type = SSH_CHANNEL_OPEN;
1492: if (compat20) {
1493: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1494: packet_put_int(c->remote_id);
1495: packet_put_int(c->self);
1496: packet_put_int(c->local_window);
1497: packet_put_int(c->local_maxpacket);
1498: } else {
1499: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1500: packet_put_int(c->remote_id);
1501: packet_put_int(c->self);
1502: }
1.75 markus 1503: } else {
1.276 djm 1504: debug("channel %d: connection failed: %s",
1.114 markus 1505: c->self, strerror(err));
1.276 djm 1506: /* Try next address, if any */
1507: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1508: close(c->sock);
1509: c->sock = c->rfd = c->wfd = sock;
1510: channel_max_fd = channel_find_maxfd();
1511: return;
1512: }
1513: /* Exhausted all addresses */
1514: error("connect_to %.100s port %d: failed.",
1515: c->connect_ctx.host, c->connect_ctx.port);
1516: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1517: if (compat20) {
1518: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1519: packet_put_int(c->remote_id);
1520: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1521: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1522: packet_put_cstring(strerror(err));
1523: packet_put_cstring("");
1524: }
1.75 markus 1525: } else {
1.114 markus 1526: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1527: packet_put_int(c->remote_id);
1.75 markus 1528: }
1.114 markus 1529: chan_mark_dead(c);
1.75 markus 1530: }
1.114 markus 1531: packet_send();
1.75 markus 1532: }
1533: }
1534:
1.259 stevesk 1535: /* ARGSUSED */
1.127 itojun 1536: static int
1.237 deraadt 1537: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1538: {
1.214 markus 1539: char buf[CHAN_RBUF];
1.41 markus 1540: int len;
1.25 markus 1541:
1.118 markus 1542: if (c->rfd != -1 &&
1.41 markus 1543: FD_ISSET(c->rfd, readset)) {
1544: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1545: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1546: return 1;
1.41 markus 1547: if (len <= 0) {
1.194 markus 1548: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1549: c->self, c->rfd, len);
1.104 markus 1550: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1551: debug2("channel %d: not open", c->self);
1.113 markus 1552: chan_mark_dead(c);
1.103 markus 1553: return -1;
1.104 markus 1554: } else if (compat13) {
1.158 markus 1555: buffer_clear(&c->output);
1.41 markus 1556: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1557: debug2("channel %d: input draining.", c->self);
1.25 markus 1558: } else {
1.41 markus 1559: chan_read_failed(c);
1.25 markus 1560: }
1.41 markus 1561: return -1;
1562: }
1.143 deraadt 1563: if (c->input_filter != NULL) {
1.66 markus 1564: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1565: debug2("channel %d: filter stops", c->self);
1.65 markus 1566: chan_read_failed(c);
1567: }
1.228 reyk 1568: } else if (c->datagram) {
1569: buffer_put_string(&c->input, buf, len);
1.65 markus 1570: } else {
1571: buffer_append(&c->input, buf, len);
1572: }
1.41 markus 1573: }
1574: return 1;
1575: }
1.241 deraadt 1576:
1.259 stevesk 1577: /* ARGSUSED */
1.127 itojun 1578: static int
1.237 deraadt 1579: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1580: {
1.95 markus 1581: struct termios tio;
1.231 reyk 1582: u_char *data = NULL, *buf;
1.134 markus 1583: u_int dlen;
1.41 markus 1584: int len;
1.25 markus 1585:
1.41 markus 1586: /* Send buffered output data to the socket. */
1.118 markus 1587: if (c->wfd != -1 &&
1.41 markus 1588: FD_ISSET(c->wfd, writeset) &&
1589: buffer_len(&c->output) > 0) {
1.231 reyk 1590: if (c->output_filter != NULL) {
1591: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1592: debug2("channel %d: filter stops", c->self);
1.232 reyk 1593: if (c->type != SSH_CHANNEL_OPEN)
1594: chan_mark_dead(c);
1595: else
1596: chan_write_failed(c);
1597: return -1;
1.231 reyk 1598: }
1599: } else if (c->datagram) {
1600: buf = data = buffer_get_string(&c->output, &dlen);
1601: } else {
1602: buf = data = buffer_ptr(&c->output);
1603: dlen = buffer_len(&c->output);
1604: }
1605:
1.228 reyk 1606: if (c->datagram) {
1607: /* ignore truncated writes, datagrams might get lost */
1608: c->local_consumed += dlen + 4;
1.231 reyk 1609: len = write(c->wfd, buf, dlen);
1.228 reyk 1610: xfree(data);
1611: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1612: return 1;
1613: if (len <= 0) {
1614: if (c->type != SSH_CHANNEL_OPEN)
1615: chan_mark_dead(c);
1616: else
1617: chan_write_failed(c);
1618: return -1;
1619: }
1620: return 1;
1621: }
1.231 reyk 1622:
1623: len = write(c->wfd, buf, dlen);
1.53 markus 1624: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1625: return 1;
1.41 markus 1626: if (len <= 0) {
1.104 markus 1627: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1628: debug2("channel %d: not open", c->self);
1.113 markus 1629: chan_mark_dead(c);
1.104 markus 1630: return -1;
1631: } else if (compat13) {
1.158 markus 1632: buffer_clear(&c->output);
1.194 markus 1633: debug2("channel %d: input draining.", c->self);
1.41 markus 1634: c->type = SSH_CHANNEL_INPUT_DRAINING;
1635: } else {
1636: chan_write_failed(c);
1637: }
1638: return -1;
1.91 markus 1639: }
1.231 reyk 1640: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1641: if (tcgetattr(c->wfd, &tio) == 0 &&
1642: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1643: /*
1644: * Simulate echo to reduce the impact of
1.96 markus 1645: * traffic analysis. We need to match the
1.95 markus 1646: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1647: * (4 byte channel id + buf)
1.91 markus 1648: */
1.95 markus 1649: packet_send_ignore(4 + len);
1.91 markus 1650: packet_send();
1651: }
1.25 markus 1652: }
1.41 markus 1653: buffer_consume(&c->output, len);
1.44 markus 1654: if (compat20 && len > 0) {
1655: c->local_consumed += len;
1656: }
1657: }
1658: return 1;
1659: }
1.241 deraadt 1660:
1.127 itojun 1661: static int
1.237 deraadt 1662: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1663: {
1.214 markus 1664: char buf[CHAN_RBUF];
1.44 markus 1665: int len;
1666:
1.45 markus 1667: /** XXX handle drain efd, too */
1.44 markus 1668: if (c->efd != -1) {
1669: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1670: FD_ISSET(c->efd, writeset) &&
1671: buffer_len(&c->extended) > 0) {
1672: len = write(c->efd, buffer_ptr(&c->extended),
1673: buffer_len(&c->extended));
1.70 markus 1674: debug2("channel %d: written %d to efd %d",
1.44 markus 1675: c->self, len, c->efd);
1.93 markus 1676: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1677: return 1;
1678: if (len <= 0) {
1679: debug2("channel %d: closing write-efd %d",
1680: c->self, c->efd);
1.132 markus 1681: channel_close_fd(&c->efd);
1.93 markus 1682: } else {
1.44 markus 1683: buffer_consume(&c->extended, len);
1684: c->local_consumed += len;
1685: }
1686: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1687: FD_ISSET(c->efd, readset)) {
1688: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1689: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1690: c->self, len, c->efd);
1.93 markus 1691: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1692: return 1;
1693: if (len <= 0) {
1694: debug2("channel %d: closing read-efd %d",
1.45 markus 1695: c->self, c->efd);
1.132 markus 1696: channel_close_fd(&c->efd);
1.93 markus 1697: } else {
1.44 markus 1698: buffer_append(&c->extended, buf, len);
1.93 markus 1699: }
1.44 markus 1700: }
1701: }
1702: return 1;
1703: }
1.241 deraadt 1704:
1.259 stevesk 1705: /* ARGSUSED */
1.127 itojun 1706: static int
1.237 deraadt 1707: channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
1.204 djm 1708: {
1709: char buf[16];
1710: int len;
1711:
1712: /* Monitor control fd to detect if the slave client exits */
1713: if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1714: len = read(c->ctl_fd, buf, sizeof(buf));
1715: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1716: return 1;
1717: if (len <= 0) {
1718: debug2("channel %d: ctl read<=0", c->self);
1719: if (c->type != SSH_CHANNEL_OPEN) {
1720: debug2("channel %d: not open", c->self);
1721: chan_mark_dead(c);
1722: return -1;
1723: } else {
1724: chan_read_failed(c);
1725: chan_write_failed(c);
1726: }
1727: return -1;
1728: } else
1729: fatal("%s: unexpected data on ctl fd", __func__);
1730: }
1731: return 1;
1732: }
1.241 deraadt 1733:
1.204 djm 1734: static int
1.93 markus 1735: channel_check_window(Channel *c)
1.44 markus 1736: {
1.104 markus 1737: if (c->type == SSH_CHANNEL_OPEN &&
1738: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1739: ((c->local_window_max - c->local_window >
1.269 markus 1740: c->local_maxpacket*3) ||
1741: c->local_window < c->local_window_max/2) &&
1.44 markus 1742: c->local_consumed > 0) {
1743: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1744: packet_put_int(c->remote_id);
1745: packet_put_int(c->local_consumed);
1746: packet_send();
1.70 markus 1747: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1748: c->self, c->local_window,
1749: c->local_consumed);
1750: c->local_window += c->local_consumed;
1751: c->local_consumed = 0;
1.1 deraadt 1752: }
1.41 markus 1753: return 1;
1.1 deraadt 1754: }
1755:
1.127 itojun 1756: static void
1.237 deraadt 1757: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1758: {
1.137 markus 1759: if (c->delayed)
1760: return;
1.41 markus 1761: channel_handle_rfd(c, readset, writeset);
1762: channel_handle_wfd(c, readset, writeset);
1.157 markus 1763: if (!compat20)
1.137 markus 1764: return;
1.44 markus 1765: channel_handle_efd(c, readset, writeset);
1.204 djm 1766: channel_handle_ctl(c, readset, writeset);
1.93 markus 1767: channel_check_window(c);
1.44 markus 1768: }
1769:
1.259 stevesk 1770: /* ARGSUSED */
1.127 itojun 1771: static void
1.237 deraadt 1772: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1773: {
1.41 markus 1774: int len;
1.180 deraadt 1775:
1.41 markus 1776: /* Send buffered output data to the socket. */
1777: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1778: len = write(c->sock, buffer_ptr(&c->output),
1779: buffer_len(&c->output));
1780: if (len <= 0)
1.158 markus 1781: buffer_clear(&c->output);
1.41 markus 1782: else
1783: buffer_consume(&c->output, len);
1784: }
1785: }
1.25 markus 1786:
1.127 itojun 1787: static void
1.44 markus 1788: channel_handler_init_20(void)
1789: {
1.157 markus 1790: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1791: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1792: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1793: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1794: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1795: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1796: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1797: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1798:
1.157 markus 1799: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1800: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1801: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1802: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1803: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1804: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1805: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1806: }
1807:
1.127 itojun 1808: static void
1.41 markus 1809: channel_handler_init_13(void)
1810: {
1811: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1812: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1813: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1814: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1815: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1816: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1817: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1818: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1819: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1820:
1.157 markus 1821: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1822: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1823: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1824: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1825: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1826: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1827: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1828: }
1.25 markus 1829:
1.127 itojun 1830: static void
1.41 markus 1831: channel_handler_init_15(void)
1832: {
1.157 markus 1833: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1834: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1835: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1836: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1837: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1838: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1839: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1840:
1.41 markus 1841: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1842: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1843: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1844: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1845: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1846: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1847: }
1.27 markus 1848:
1.127 itojun 1849: static void
1.41 markus 1850: channel_handler_init(void)
1851: {
1852: int i;
1.180 deraadt 1853:
1.148 deraadt 1854: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1855: channel_pre[i] = NULL;
1856: channel_post[i] = NULL;
1857: }
1.44 markus 1858: if (compat20)
1859: channel_handler_init_20();
1860: else if (compat13)
1.41 markus 1861: channel_handler_init_13();
1862: else
1863: channel_handler_init_15();
1864: }
1.25 markus 1865:
1.140 markus 1866: /* gc dead channels */
1867: static void
1868: channel_garbage_collect(Channel *c)
1869: {
1870: if (c == NULL)
1871: return;
1872: if (c->detach_user != NULL) {
1.225 djm 1873: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1874: return;
1.194 markus 1875: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1876: c->detach_user(c->self, NULL);
1877: /* if we still have a callback */
1878: if (c->detach_user != NULL)
1879: return;
1.194 markus 1880: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1881: }
1882: if (!chan_is_dead(c, 1))
1883: return;
1.194 markus 1884: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1885: channel_free(c);
1886: }
1887:
1.127 itojun 1888: static void
1.237 deraadt 1889: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
1.41 markus 1890: {
1891: static int did_init = 0;
1.209 avsm 1892: u_int i;
1.41 markus 1893: Channel *c;
1.25 markus 1894:
1.41 markus 1895: if (!did_init) {
1896: channel_handler_init();
1897: did_init = 1;
1898: }
1899: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1900: c = channels[i];
1901: if (c == NULL)
1.41 markus 1902: continue;
1.118 markus 1903: if (ftab[c->type] != NULL)
1904: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1905: channel_garbage_collect(c);
1.1 deraadt 1906: }
1907: }
1908:
1.121 markus 1909: /*
1910: * Allocate/update select bitmasks and add any bits relevant to channels in
1911: * select bitmasks.
1912: */
1.49 markus 1913: void
1.100 markus 1914: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.209 avsm 1915: u_int *nallocp, int rekeying)
1.41 markus 1916: {
1.243 djm 1917: u_int n, sz, nfdset;
1.84 markus 1918:
1919: n = MAX(*maxfdp, channel_max_fd);
1920:
1.243 djm 1921: nfdset = howmany(n+1, NFDBITS);
1922: /* Explicitly test here, because xrealloc isn't always called */
1923: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1924: fatal("channel_prepare_select: max_fd (%d) is too large", n);
1925: sz = nfdset * sizeof(fd_mask);
1926:
1.132 markus 1927: /* perhaps check sz < nalloc/2 and shrink? */
1928: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 1929: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1930: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 1931: *nallocp = sz;
1.84 markus 1932: }
1.132 markus 1933: *maxfdp = n;
1.84 markus 1934: memset(*readsetp, 0, sz);
1935: memset(*writesetp, 0, sz);
1936:
1.100 markus 1937: if (!rekeying)
1938: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1939: }
1940:
1.121 markus 1941: /*
1942: * After select, perform any appropriate operations for channels which have
1943: * events pending.
1944: */
1.49 markus 1945: void
1.237 deraadt 1946: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 1947: {
1948: channel_handler(channel_post, readset, writeset);
1949: }
1950:
1.121 markus 1951:
1.84 markus 1952: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 1953: void
1.142 itojun 1954: channel_output_poll(void)
1.1 deraadt 1955: {
1.41 markus 1956: Channel *c;
1.209 avsm 1957: u_int i, len;
1.1 deraadt 1958:
1.25 markus 1959: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1960: c = channels[i];
1961: if (c == NULL)
1962: continue;
1.37 markus 1963:
1.121 markus 1964: /*
1965: * We are only interested in channels that can have buffered
1966: * incoming data.
1967: */
1.37 markus 1968: if (compat13) {
1.41 markus 1969: if (c->type != SSH_CHANNEL_OPEN &&
1970: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1971: continue;
1972: } else {
1.41 markus 1973: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1974: continue;
1975: }
1.46 markus 1976: if (compat20 &&
1977: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1978: /* XXX is this true? */
1.140 markus 1979: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1980: continue;
1981: }
1.25 markus 1982:
1983: /* Get the amount of buffered data for this channel. */
1.93 markus 1984: if ((c->istate == CHAN_INPUT_OPEN ||
1985: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1986: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 1987: if (c->datagram) {
1988: if (len > 0) {
1989: u_char *data;
1990: u_int dlen;
1991:
1992: data = buffer_get_string(&c->input,
1993: &dlen);
1994: packet_start(SSH2_MSG_CHANNEL_DATA);
1995: packet_put_int(c->remote_id);
1996: packet_put_string(data, dlen);
1997: packet_send();
1998: c->remote_window -= dlen + 4;
1999: xfree(data);
2000: }
2001: continue;
2002: }
1.121 markus 2003: /*
2004: * Send some data for the other side over the secure
2005: * connection.
2006: */
1.44 markus 2007: if (compat20) {
2008: if (len > c->remote_window)
2009: len = c->remote_window;
2010: if (len > c->remote_maxpacket)
2011: len = c->remote_maxpacket;
1.25 markus 2012: } else {
1.44 markus 2013: if (packet_is_interactive()) {
2014: if (len > 1024)
2015: len = 512;
2016: } else {
2017: /* Keep the packets at reasonable size. */
2018: if (len > packet_get_maxsize()/2)
2019: len = packet_get_maxsize()/2;
2020: }
1.25 markus 2021: }
1.41 markus 2022: if (len > 0) {
1.44 markus 2023: packet_start(compat20 ?
2024: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2025: packet_put_int(c->remote_id);
2026: packet_put_string(buffer_ptr(&c->input), len);
2027: packet_send();
2028: buffer_consume(&c->input, len);
2029: c->remote_window -= len;
2030: }
2031: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2032: if (compat13)
2033: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2034: /*
2035: * input-buffer is empty and read-socket shutdown:
1.172 markus 2036: * tell peer, that we will not send more data: send IEOF.
2037: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2038: */
1.172 markus 2039: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2040: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2041: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2042: else
2043: chan_ibuf_empty(c);
1.25 markus 2044: }
1.44 markus 2045: /* Send extended data, i.e. stderr */
2046: if (compat20 &&
1.172 markus 2047: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2048: c->remote_window > 0 &&
2049: (len = buffer_len(&c->extended)) > 0 &&
2050: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2051: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2052: c->self, c->remote_window, buffer_len(&c->extended),
2053: c->extended_usage);
1.44 markus 2054: if (len > c->remote_window)
2055: len = c->remote_window;
2056: if (len > c->remote_maxpacket)
2057: len = c->remote_maxpacket;
2058: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2059: packet_put_int(c->remote_id);
2060: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2061: packet_put_string(buffer_ptr(&c->extended), len);
2062: packet_send();
2063: buffer_consume(&c->extended, len);
2064: c->remote_window -= len;
1.93 markus 2065: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2066: }
1.25 markus 2067: }
1.1 deraadt 2068: }
2069:
1.121 markus 2070:
2071: /* -- protocol input */
1.249 djm 2072:
2073: /* ARGSUSED */
1.49 markus 2074: void
1.154 markus 2075: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2076: {
1.37 markus 2077: int id;
1.25 markus 2078: char *data;
1.77 markus 2079: u_int data_len;
1.41 markus 2080: Channel *c;
1.25 markus 2081:
2082: /* Get the channel number and verify it. */
1.37 markus 2083: id = packet_get_int();
1.41 markus 2084: c = channel_lookup(id);
2085: if (c == NULL)
1.37 markus 2086: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2087:
2088: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2089: if (c->type != SSH_CHANNEL_OPEN &&
2090: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 2091: return;
2092:
1.25 markus 2093: /* Get the data. */
1.274 markus 2094: data = packet_get_string_ptr(&data_len);
1.200 markus 2095:
2096: /*
2097: * Ignore data for protocol > 1.3 if output end is no longer open.
2098: * For protocol 2 the sending side is reducing its window as it sends
2099: * data, so we must 'fake' consumption of the data in order to ensure
2100: * that window updates are sent back. Otherwise the connection might
2101: * deadlock.
2102: */
2103: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2104: if (compat20) {
2105: c->local_window -= data_len;
2106: c->local_consumed += data_len;
2107: }
2108: return;
2109: }
1.41 markus 2110:
1.143 deraadt 2111: if (compat20) {
1.44 markus 2112: if (data_len > c->local_maxpacket) {
1.188 itojun 2113: logit("channel %d: rcvd big packet %d, maxpack %d",
1.44 markus 2114: c->self, data_len, c->local_maxpacket);
2115: }
2116: if (data_len > c->local_window) {
1.188 itojun 2117: logit("channel %d: rcvd too much data %d, win %d",
1.44 markus 2118: c->self, data_len, c->local_window);
2119: return;
2120: }
2121: c->local_window -= data_len;
2122: }
1.228 reyk 2123: if (c->datagram)
2124: buffer_put_string(&c->output, data, data_len);
2125: else
2126: buffer_append(&c->output, data, data_len);
1.274 markus 2127: packet_check_eom();
1.1 deraadt 2128: }
1.121 markus 2129:
1.249 djm 2130: /* ARGSUSED */
1.49 markus 2131: void
1.154 markus 2132: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2133: {
2134: int id;
2135: char *data;
1.177 markus 2136: u_int data_len, tcode;
1.44 markus 2137: Channel *c;
2138:
2139: /* Get the channel number and verify it. */
2140: id = packet_get_int();
2141: c = channel_lookup(id);
2142:
2143: if (c == NULL)
2144: packet_disconnect("Received extended_data for bad channel %d.", id);
2145: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2146: logit("channel %d: ext data for non open", id);
1.44 markus 2147: return;
1.172 markus 2148: }
2149: if (c->flags & CHAN_EOF_RCVD) {
2150: if (datafellows & SSH_BUG_EXTEOF)
2151: debug("channel %d: accepting ext data after eof", id);
2152: else
2153: packet_disconnect("Received extended_data after EOF "
2154: "on channel %d.", id);
1.44 markus 2155: }
2156: tcode = packet_get_int();
2157: if (c->efd == -1 ||
2158: c->extended_usage != CHAN_EXTENDED_WRITE ||
2159: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2160: logit("channel %d: bad ext data", c->self);
1.44 markus 2161: return;
2162: }
2163: data = packet_get_string(&data_len);
1.152 markus 2164: packet_check_eom();
1.44 markus 2165: if (data_len > c->local_window) {
1.188 itojun 2166: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2167: c->self, data_len, c->local_window);
2168: xfree(data);
2169: return;
2170: }
1.70 markus 2171: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2172: c->local_window -= data_len;
2173: buffer_append(&c->extended, data, data_len);
2174: xfree(data);
2175: }
2176:
1.249 djm 2177: /* ARGSUSED */
1.49 markus 2178: void
1.154 markus 2179: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2180: {
2181: int id;
2182: Channel *c;
2183:
2184: id = packet_get_int();
1.152 markus 2185: packet_check_eom();
1.41 markus 2186: c = channel_lookup(id);
2187: if (c == NULL)
2188: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2189: chan_rcvd_ieof(c);
1.133 markus 2190:
2191: /* XXX force input close */
1.156 markus 2192: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2193: debug("channel %d: FORCE input drain", c->self);
2194: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2195: if (buffer_len(&c->input) == 0)
2196: chan_ibuf_empty(c);
1.133 markus 2197: }
2198:
1.41 markus 2199: }
1.1 deraadt 2200:
1.249 djm 2201: /* ARGSUSED */
1.49 markus 2202: void
1.154 markus 2203: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2204: {
1.41 markus 2205: int id;
2206: Channel *c;
1.1 deraadt 2207:
1.41 markus 2208: id = packet_get_int();
1.152 markus 2209: packet_check_eom();
1.41 markus 2210: c = channel_lookup(id);
2211: if (c == NULL)
2212: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2213:
2214: /*
2215: * Send a confirmation that we have closed the channel and no more
2216: * data is coming for it.
2217: */
1.25 markus 2218: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2219: packet_put_int(c->remote_id);
1.25 markus 2220: packet_send();
2221:
1.27 markus 2222: /*
2223: * If the channel is in closed state, we have sent a close request,
2224: * and the other side will eventually respond with a confirmation.
2225: * Thus, we cannot free the channel here, because then there would be
2226: * no-one to receive the confirmation. The channel gets freed when
2227: * the confirmation arrives.
2228: */
1.41 markus 2229: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2230: /*
2231: * Not a closed channel - mark it as draining, which will
2232: * cause it to be freed later.
2233: */
1.158 markus 2234: buffer_clear(&c->input);
1.41 markus 2235: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2236: }
1.1 deraadt 2237: }
2238:
1.41 markus 2239: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2240: /* ARGSUSED */
1.49 markus 2241: void
1.154 markus 2242: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2243: {
2244: int id = packet_get_int();
2245: Channel *c = channel_lookup(id);
1.151 markus 2246:
1.152 markus 2247: packet_check_eom();
1.41 markus 2248: if (c == NULL)
2249: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2250: chan_rcvd_oclose(c);
2251: }
1.1 deraadt 2252:
1.249 djm 2253: /* ARGSUSED */
1.49 markus 2254: void
1.154 markus 2255: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2256: {
1.41 markus 2257: int id = packet_get_int();
2258: Channel *c = channel_lookup(id);
1.1 deraadt 2259:
1.152 markus 2260: packet_check_eom();
1.41 markus 2261: if (c == NULL)
2262: packet_disconnect("Received close confirmation for "
2263: "out-of-range channel %d.", id);
2264: if (c->type != SSH_CHANNEL_CLOSED)
2265: packet_disconnect("Received close confirmation for "
2266: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2267: channel_free(c);
1.1 deraadt 2268: }
2269:
1.249 djm 2270: /* ARGSUSED */
1.49 markus 2271: void
1.154 markus 2272: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2273: {
1.41 markus 2274: int id, remote_id;
2275: Channel *c;
1.1 deraadt 2276:
1.41 markus 2277: id = packet_get_int();
2278: c = channel_lookup(id);
1.25 markus 2279:
1.41 markus 2280: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2281: packet_disconnect("Received open confirmation for "
2282: "non-opening channel %d.", id);
2283: remote_id = packet_get_int();
1.27 markus 2284: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2285: c->remote_id = remote_id;
2286: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2287:
2288: if (compat20) {
2289: c->remote_window = packet_get_int();
2290: c->remote_maxpacket = packet_get_int();
1.275 djm 2291: if (c->open_confirm) {
1.70 markus 2292: debug2("callback start");
1.275 djm 2293: c->open_confirm(c->self, c->open_confirm_ctx);
1.70 markus 2294: debug2("callback done");
1.44 markus 2295: }
1.194 markus 2296: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2297: c->remote_window, c->remote_maxpacket);
2298: }
1.152 markus 2299: packet_check_eom();
1.1 deraadt 2300: }
2301:
1.127 itojun 2302: static char *
1.114 markus 2303: reason2txt(int reason)
2304: {
1.143 deraadt 2305: switch (reason) {
1.114 markus 2306: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2307: return "administratively prohibited";
2308: case SSH2_OPEN_CONNECT_FAILED:
2309: return "connect failed";
2310: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2311: return "unknown channel type";
2312: case SSH2_OPEN_RESOURCE_SHORTAGE:
2313: return "resource shortage";
2314: }
1.117 stevesk 2315: return "unknown reason";
1.114 markus 2316: }
2317:
1.249 djm 2318: /* ARGSUSED */
1.49 markus 2319: void
1.154 markus 2320: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2321: {
1.86 markus 2322: int id, reason;
2323: char *msg = NULL, *lang = NULL;
1.41 markus 2324: Channel *c;
2325:
2326: id = packet_get_int();
2327: c = channel_lookup(id);
1.25 markus 2328:
1.41 markus 2329: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2330: packet_disconnect("Received open failure for "
2331: "non-opening channel %d.", id);
1.44 markus 2332: if (compat20) {
1.86 markus 2333: reason = packet_get_int();
1.110 markus 2334: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2335: msg = packet_get_string(NULL);
2336: lang = packet_get_string(NULL);
2337: }
1.188 itojun 2338: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2339: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 2340: if (msg != NULL)
2341: xfree(msg);
2342: if (lang != NULL)
2343: xfree(lang);
1.44 markus 2344: }
1.152 markus 2345: packet_check_eom();
1.291 djm 2346: /* Schedule the channel for cleanup/deletion. */
2347: chan_mark_dead(c);
1.44 markus 2348: }
2349:
1.249 djm 2350: /* ARGSUSED */
1.121 markus 2351: void
1.154 markus 2352: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2353: {
2354: Channel *c;
1.178 markus 2355: int id;
2356: u_int adjust;
1.121 markus 2357:
2358: if (!compat20)
2359: return;
2360:
2361: /* Get the channel number and verify it. */
2362: id = packet_get_int();
2363: c = channel_lookup(id);
1.1 deraadt 2364:
1.229 markus 2365: if (c == NULL) {
2366: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2367: return;
2368: }
2369: adjust = packet_get_int();
1.152 markus 2370: packet_check_eom();
1.178 markus 2371: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2372: c->remote_window += adjust;
2373: }
1.1 deraadt 2374:
1.249 djm 2375: /* ARGSUSED */
1.121 markus 2376: void
1.154 markus 2377: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2378: {
1.121 markus 2379: Channel *c = NULL;
2380: u_short host_port;
2381: char *host, *originator_string;
1.276 djm 2382: int remote_id;
1.121 markus 2383:
2384: remote_id = packet_get_int();
2385: host = packet_get_string(NULL);
2386: host_port = packet_get_int();
1.25 markus 2387:
1.121 markus 2388: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2389: originator_string = packet_get_string(NULL);
2390: } else {
2391: originator_string = xstrdup("unknown (remote did not supply name)");
2392: }
1.152 markus 2393: packet_check_eom();
1.276 djm 2394: c = channel_connect_to(host, host_port,
2395: "connected socket", originator_string);
1.190 markus 2396: xfree(originator_string);
1.276 djm 2397: xfree(host);
1.121 markus 2398: if (c == NULL) {
2399: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2400: packet_put_int(remote_id);
2401: packet_send();
1.276 djm 2402: } else
2403: c->remote_id = remote_id;
1.1 deraadt 2404: }
2405:
1.275 djm 2406: /* ARGSUSED */
2407: void
2408: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2409: {
2410: Channel *c;
2411: struct channel_confirm *cc;
1.289 markus 2412: int id;
1.275 djm 2413:
2414: /* Reset keepalive timeout */
1.296 andreas 2415: packet_set_alive_timeouts(0);
1.275 djm 2416:
1.289 markus 2417: id = packet_get_int();
1.275 djm 2418: packet_check_eom();
2419:
1.289 markus 2420: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2421:
1.289 markus 2422: if ((c = channel_lookup(id)) == NULL) {
2423: logit("channel_input_status_confirm: %d: unknown", id);
1.275 djm 2424: return;
2425: }
2426: ;
2427: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
2428: return;
2429: cc->cb(type, c, cc->ctx);
2430: TAILQ_REMOVE(&c->status_confirms, cc, entry);
2431: bzero(cc, sizeof(*cc));
2432: xfree(cc);
2433: }
1.121 markus 2434:
2435: /* -- tcp forwarding */
1.135 markus 2436:
2437: void
2438: channel_set_af(int af)
2439: {
2440: IPv4or6 = af;
2441: }
1.121 markus 2442:
1.297 ! reyk 2443: void
! 2444: channel_set_rdomain(int rdomain)
! 2445: {
! 2446: channel_rdomain = rdomain;
! 2447: }
! 2448:
1.160 markus 2449: static int
1.295 djm 2450: channel_setup_fwd_listener(int type, const char *listen_addr,
2451: u_short listen_port, int *allocated_listen_port,
1.160 markus 2452: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2453: {
1.113 markus 2454: Channel *c;
1.226 djm 2455: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2456: struct addrinfo hints, *ai, *aitop;
1.212 djm 2457: const char *host, *addr;
1.35 markus 2458: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2459: in_port_t *lport_p;
1.25 markus 2460:
1.160 markus 2461: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2462: listen_addr : host_to_connect;
1.212 djm 2463: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2464:
1.160 markus 2465: if (host == NULL) {
2466: error("No forward host name.");
1.218 markus 2467: return 0;
1.73 markus 2468: }
1.294 djm 2469: if (strlen(host) >= NI_MAXHOST) {
1.87 markus 2470: error("Forward host name too long.");
1.218 markus 2471: return 0;
1.87 markus 2472: }
1.25 markus 2473:
1.28 markus 2474: /*
1.212 djm 2475: * Determine whether or not a port forward listens to loopback,
1.213 deraadt 2476: * specified address or wildcard. On the client, a specified bind
2477: * address will always override gateway_ports. On the server, a
2478: * gateway_ports of 1 (``yes'') will override the client's
2479: * specification and force a wildcard bind, whereas a value of 2
2480: * (``clientspecified'') will bind to whatever address the client
1.212 djm 2481: * asked for.
2482: *
2483: * Special-case listen_addrs are:
2484: *
2485: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2486: * "" (empty string), "*" -> wildcard v4/v6
2487: * "localhost" -> loopback v4/v6
2488: */
2489: addr = NULL;
2490: if (listen_addr == NULL) {
2491: /* No address specified: default to gateway_ports setting */
2492: if (gateway_ports)
2493: wildcard = 1;
2494: } else if (gateway_ports || is_client) {
2495: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
1.272 djm 2496: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
1.212 djm 2497: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2498: (!is_client && gateway_ports == 1))
2499: wildcard = 1;
2500: else if (strcmp(listen_addr, "localhost") != 0)
2501: addr = listen_addr;
2502: }
2503:
2504: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2505: type, wildcard, (addr == NULL) ? "NULL" : addr);
2506:
2507: /*
1.35 markus 2508: * getaddrinfo returns a loopback address if the hostname is
2509: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2510: */
1.35 markus 2511: memset(&hints, 0, sizeof(hints));
2512: hints.ai_family = IPv4or6;
1.212 djm 2513: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2514: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2515: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2516: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2517: if (addr == NULL) {
2518: /* This really shouldn't happen */
2519: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2520: ssh_gai_strerror(r));
1.212 djm 2521: } else {
1.218 markus 2522: error("channel_setup_fwd_listener: "
1.271 dtucker 2523: "getaddrinfo(%.64s): %s", addr,
2524: ssh_gai_strerror(r));
1.212 djm 2525: }
1.218 markus 2526: return 0;
1.212 djm 2527: }
1.295 djm 2528: if (allocated_listen_port != NULL)
2529: *allocated_listen_port = 0;
1.35 markus 2530: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2531: switch (ai->ai_family) {
2532: case AF_INET:
2533: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2534: sin_port;
2535: break;
2536: case AF_INET6:
2537: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2538: sin6_port;
2539: break;
2540: default:
1.35 markus 2541: continue;
1.295 djm 2542: }
2543: /*
2544: * If allocating a port for -R forwards, then use the
2545: * same port for all address families.
2546: */
2547: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2548: allocated_listen_port != NULL && *allocated_listen_port > 0)
2549: *lport_p = htons(*allocated_listen_port);
2550:
1.35 markus 2551: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2552: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2553: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2554: continue;
2555: }
2556: /* Create a port to listen for the host. */
1.297 ! reyk 2557: sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
! 2558: ai->ai_protocol, channel_rdomain);
1.35 markus 2559: if (sock < 0) {
2560: /* this is no error since kernel may not support ipv6 */
2561: verbose("socket: %.100s", strerror(errno));
2562: continue;
2563: }
1.226 djm 2564:
2565: channel_set_reuseaddr(sock);
1.182 stevesk 2566:
1.295 djm 2567: debug("Local forwarding listening on %s port %s.",
2568: ntop, strport);
1.35 markus 2569:
2570: /* Bind the socket to the address. */
2571: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2572: /* address can be in use ipv6 address is already bound */
2573: verbose("bind: %.100s", strerror(errno));
2574: close(sock);
2575: continue;
2576: }
2577: /* Start listening for connections on the socket. */
1.199 markus 2578: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2579: error("listen: %.100s", strerror(errno));
2580: close(sock);
2581: continue;
2582: }
1.295 djm 2583:
2584: /*
2585: * listen_port == 0 requests a dynamically allocated port -
2586: * record what we got.
2587: */
2588: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2589: allocated_listen_port != NULL &&
2590: *allocated_listen_port == 0) {
2591: *allocated_listen_port = get_sock_port(sock, 1);
2592: debug("Allocated listen port %d",
2593: *allocated_listen_port);
2594: }
2595:
1.35 markus 2596: /* Allocate a channel number for the socket. */
1.121 markus 2597: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2598: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2599: 0, "port listener", 1);
1.293 djm 2600: c->path = xstrdup(host);
1.113 markus 2601: c->host_port = port_to_connect;
2602: c->listening_port = listen_port;
1.35 markus 2603: success = 1;
2604: }
2605: if (success == 0)
1.160 markus 2606: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2607: listen_port);
1.35 markus 2608: freeaddrinfo(aitop);
1.87 markus 2609: return success;
1.25 markus 2610: }
1.1 deraadt 2611:
1.202 djm 2612: int
2613: channel_cancel_rport_listener(const char *host, u_short port)
2614: {
1.209 avsm 2615: u_int i;
2616: int found = 0;
1.202 djm 2617:
1.213 deraadt 2618: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2619: Channel *c = channels[i];
2620:
2621: if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
1.293 djm 2622: strcmp(c->path, host) == 0 && c->listening_port == port) {
1.210 djm 2623: debug2("%s: close channel %d", __func__, i);
1.202 djm 2624: channel_free(c);
2625: found = 1;
2626: }
2627: }
2628:
2629: return (found);
2630: }
2631:
1.160 markus 2632: /* protocol local port fwd, used by ssh (and sshd in v1) */
2633: int
1.212 djm 2634: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2635: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2636: {
2637: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.295 djm 2638: listen_host, listen_port, NULL, host_to_connect, port_to_connect,
1.212 djm 2639: gateway_ports);
1.160 markus 2640: }
2641:
2642: /* protocol v2 remote port fwd, used by sshd */
2643: int
2644: channel_setup_remote_fwd_listener(const char *listen_address,
1.295 djm 2645: u_short listen_port, int *allocated_listen_port, int gateway_ports)
1.160 markus 2646: {
2647: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
1.295 djm 2648: listen_address, listen_port, allocated_listen_port,
2649: NULL, 0, gateway_ports);
1.160 markus 2650: }
2651:
1.27 markus 2652: /*
2653: * Initiate forwarding of connections to port "port" on remote host through
2654: * the secure channel to host:port from local side.
2655: */
1.1 deraadt 2656:
1.253 markus 2657: int
1.212 djm 2658: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2659: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2660: {
1.153 markus 2661: int type, success = 0;
1.73 markus 2662:
1.25 markus 2663: /* Record locally that connection to this host/port is permitted. */
2664: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2665: fatal("channel_request_remote_forwarding: too many forwards");
2666:
2667: /* Send the forward request to the remote side. */
1.44 markus 2668: if (compat20) {
1.212 djm 2669: const char *address_to_bind;
1.267 djm 2670: if (listen_host == NULL) {
2671: if (datafellows & SSH_BUG_RFWD_ADDR)
2672: address_to_bind = "127.0.0.1";
2673: else
2674: address_to_bind = "localhost";
2675: } else if (*listen_host == '\0' ||
2676: strcmp(listen_host, "*") == 0) {
2677: if (datafellows & SSH_BUG_RFWD_ADDR)
2678: address_to_bind = "0.0.0.0";
2679: else
2680: address_to_bind = "";
2681: } else
1.212 djm 2682: address_to_bind = listen_host;
2683:
1.44 markus 2684: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2685: packet_put_cstring("tcpip-forward");
1.173 markus 2686: packet_put_char(1); /* boolean: want reply */
1.44 markus 2687: packet_put_cstring(address_to_bind);
2688: packet_put_int(listen_port);
1.73 markus 2689: packet_send();
2690: packet_write_wait();
2691: /* Assume that server accepts the request */
2692: success = 1;
1.44 markus 2693: } else {
2694: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2695: packet_put_int(listen_port);
2696: packet_put_cstring(host_to_connect);
1.44 markus 2697: packet_put_int(port_to_connect);
2698: packet_send();
2699: packet_write_wait();
1.73 markus 2700:
2701: /* Wait for response from the remote side. */
1.153 markus 2702: type = packet_read();
1.73 markus 2703: switch (type) {
2704: case SSH_SMSG_SUCCESS:
2705: success = 1;
2706: break;
2707: case SSH_SMSG_FAILURE:
2708: break;
2709: default:
2710: /* Unknown packet */
2711: packet_disconnect("Protocol error for port forward request:"
2712: "received packet type %d.", type);
2713: }
2714: }
2715: if (success) {
2716: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2717: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2718: permitted_opens[num_permitted_opens].listen_port = listen_port;
2719: num_permitted_opens++;
1.44 markus 2720: }
1.253 markus 2721: return (success ? 0 : -1);
1.1 deraadt 2722: }
2723:
1.27 markus 2724: /*
1.208 deraadt 2725: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 2726: * local side.
2727: */
2728: void
1.212 djm 2729: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 2730: {
2731: int i;
2732:
2733: if (!compat20)
2734: return;
2735:
2736: for (i = 0; i < num_permitted_opens; i++) {
1.208 deraadt 2737: if (permitted_opens[i].host_to_connect != NULL &&
1.202 djm 2738: permitted_opens[i].listen_port == port)
2739: break;
2740: }
2741: if (i >= num_permitted_opens) {
2742: debug("%s: requested forward not found", __func__);
2743: return;
2744: }
2745: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2746: packet_put_cstring("cancel-tcpip-forward");
2747: packet_put_char(0);
1.212 djm 2748: packet_put_cstring(host == NULL ? "" : host);
1.202 djm 2749: packet_put_int(port);
2750: packet_send();
2751:
2752: permitted_opens[i].listen_port = 0;
2753: permitted_opens[i].port_to_connect = 0;
1.227 stevesk 2754: xfree(permitted_opens[i].host_to_connect);
1.202 djm 2755: permitted_opens[i].host_to_connect = NULL;
2756: }
2757:
2758: /*
1.27 markus 2759: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2760: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 2761: * message if there was an error).
1.27 markus 2762: */
1.253 markus 2763: int
1.56 markus 2764: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2765: {
1.31 markus 2766: u_short port, host_port;
1.253 markus 2767: int success = 0;
1.25 markus 2768: char *hostname;
1.1 deraadt 2769:
1.25 markus 2770: /* Get arguments from the packet. */
2771: port = packet_get_int();
2772: hostname = packet_get_string(NULL);
2773: host_port = packet_get_int();
2774:
1.27 markus 2775: /*
2776: * Check that an unprivileged user is not trying to forward a
2777: * privileged port.
2778: */
1.25 markus 2779: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 2780: packet_disconnect(
2781: "Requested forwarding of port %d but user is not root.",
2782: port);
2783: if (host_port == 0)
2784: packet_disconnect("Dynamic forwarding denied.");
2785:
1.73 markus 2786: /* Initiate forwarding */
1.253 markus 2787: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 2788: host_port, gateway_ports);
1.25 markus 2789:
2790: /* Free the argument string. */
2791: xfree(hostname);
1.253 markus 2792:
2793: return (success ? 0 : -1);
1.1 deraadt 2794: }
2795:
1.99 markus 2796: /*
2797: * Permits opening to any host/port if permitted_opens[] is empty. This is
2798: * usually called by the server, because the user could connect to any port
2799: * anyway, and the server has no way to know but to trust the client anyway.
2800: */
2801: void
1.142 itojun 2802: channel_permit_all_opens(void)
1.99 markus 2803: {
2804: if (num_permitted_opens == 0)
2805: all_opens_permitted = 1;
2806: }
2807:
1.101 markus 2808: void
1.99 markus 2809: channel_add_permitted_opens(char *host, int port)
2810: {
2811: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1.253 markus 2812: fatal("channel_add_permitted_opens: too many forwards");
1.99 markus 2813: debug("allow port forwarding to host %s port %d", host, port);
2814:
2815: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2816: permitted_opens[num_permitted_opens].port_to_connect = port;
2817: num_permitted_opens++;
2818:
2819: all_opens_permitted = 0;
2820: }
2821:
1.258 dtucker 2822: int
1.257 dtucker 2823: channel_add_adm_permitted_opens(char *host, int port)
2824: {
2825: if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2826: fatal("channel_add_adm_permitted_opens: too many forwards");
1.258 dtucker 2827: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 2828:
2829: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
2830: = xstrdup(host);
2831: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.258 dtucker 2832: return ++num_adm_permitted_opens;
1.257 dtucker 2833: }
2834:
2835: void
1.99 markus 2836: channel_clear_permitted_opens(void)
2837: {
2838: int i;
2839:
2840: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2841: if (permitted_opens[i].host_to_connect != NULL)
2842: xfree(permitted_opens[i].host_to_connect);
1.99 markus 2843: num_permitted_opens = 0;
1.257 dtucker 2844: }
2845:
2846: void
2847: channel_clear_adm_permitted_opens(void)
2848: {
2849: int i;
1.99 markus 2850:
1.257 dtucker 2851: for (i = 0; i < num_adm_permitted_opens; i++)
2852: if (permitted_adm_opens[i].host_to_connect != NULL)
2853: xfree(permitted_adm_opens[i].host_to_connect);
2854: num_adm_permitted_opens = 0;
1.278 dtucker 2855: }
2856:
2857: void
2858: channel_print_adm_permitted_opens(void)
2859: {
1.286 djm 2860: int i;
1.278 dtucker 2861:
1.290 stevesk 2862: printf("permitopen");
1.288 stevesk 2863: if (num_adm_permitted_opens == 0) {
1.290 stevesk 2864: printf(" any\n");
1.288 stevesk 2865: return;
2866: }
1.278 dtucker 2867: for (i = 0; i < num_adm_permitted_opens; i++)
2868: if (permitted_adm_opens[i].host_to_connect != NULL)
2869: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
2870: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 2871: printf("\n");
1.99 markus 2872: }
2873:
1.276 djm 2874: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 2875: static int
1.276 djm 2876: connect_next(struct channel_connect *cctx)
1.41 markus 2877: {
1.276 djm 2878: int sock, saved_errno;
1.41 markus 2879: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2880:
1.276 djm 2881: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
2882: if (cctx->ai->ai_family != AF_INET &&
2883: cctx->ai->ai_family != AF_INET6)
1.41 markus 2884: continue;
1.276 djm 2885: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
2886: ntop, sizeof(ntop), strport, sizeof(strport),
2887: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
2888: error("connect_next: getnameinfo failed");
1.41 markus 2889: continue;
2890: }
1.297 ! reyk 2891: if ((sock = socket_rdomain(cctx->ai->ai_family,
! 2892: cctx->ai->ai_socktype, cctx->ai->ai_protocol,
! 2893: channel_rdomain)) == -1) {
1.276 djm 2894: if (cctx->ai->ai_next == NULL)
1.186 djm 2895: error("socket: %.100s", strerror(errno));
2896: else
2897: verbose("socket: %.100s", strerror(errno));
1.41 markus 2898: continue;
2899: }
1.205 djm 2900: if (set_nonblock(sock) == -1)
2901: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 2902: if (connect(sock, cctx->ai->ai_addr,
2903: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
2904: debug("connect_next: host %.100s ([%.100s]:%s): "
2905: "%.100s", cctx->host, ntop, strport,
1.41 markus 2906: strerror(errno));
1.276 djm 2907: saved_errno = errno;
1.41 markus 2908: close(sock);
1.276 djm 2909: errno = saved_errno;
1.89 stevesk 2910: continue; /* fail -- try next */
1.41 markus 2911: }
1.276 djm 2912: debug("connect_next: host %.100s ([%.100s]:%s) "
2913: "in progress, fd=%d", cctx->host, ntop, strport, sock);
2914: cctx->ai = cctx->ai->ai_next;
2915: set_nodelay(sock);
2916: return sock;
2917: }
2918: return -1;
2919: }
1.41 markus 2920:
1.276 djm 2921: static void
2922: channel_connect_ctx_free(struct channel_connect *cctx)
2923: {
2924: xfree(cctx->host);
2925: if (cctx->aitop)
2926: freeaddrinfo(cctx->aitop);
2927: bzero(cctx, sizeof(*cctx));
2928: cctx->host = NULL;
2929: cctx->ai = cctx->aitop = NULL;
2930: }
2931:
2932: /* Return CONNECTING channel to remote host, port */
2933: static Channel *
2934: connect_to(const char *host, u_short port, char *ctype, char *rname)
2935: {
2936: struct addrinfo hints;
2937: int gaierr;
2938: int sock = -1;
2939: char strport[NI_MAXSERV];
2940: struct channel_connect cctx;
2941: Channel *c;
2942:
1.284 djm 2943: memset(&cctx, 0, sizeof(cctx));
1.276 djm 2944: memset(&hints, 0, sizeof(hints));
2945: hints.ai_family = IPv4or6;
2946: hints.ai_socktype = SOCK_STREAM;
2947: snprintf(strport, sizeof strport, "%d", port);
2948: if ((gaierr = getaddrinfo(host, strport, &hints, &cctx.aitop)) != 0) {
2949: error("connect_to %.100s: unknown host (%s)", host,
2950: ssh_gai_strerror(gaierr));
2951: return NULL;
1.41 markus 2952: }
1.276 djm 2953:
2954: cctx.host = xstrdup(host);
2955: cctx.port = port;
2956: cctx.ai = cctx.aitop;
2957:
2958: if ((sock = connect_next(&cctx)) == -1) {
2959: error("connect to %.100s port %d failed: %s",
2960: host, port, strerror(errno));
2961: channel_connect_ctx_free(&cctx);
2962: return NULL;
1.41 markus 2963: }
1.276 djm 2964: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
2965: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
2966: c->connect_ctx = cctx;
2967: return c;
1.41 markus 2968: }
1.99 markus 2969:
1.276 djm 2970: Channel *
2971: channel_connect_by_listen_address(u_short listen_port, char *ctype, char *rname)
1.73 markus 2972: {
2973: int i;
1.99 markus 2974:
1.276 djm 2975: for (i = 0; i < num_permitted_opens; i++) {
1.202 djm 2976: if (permitted_opens[i].host_to_connect != NULL &&
1.276 djm 2977: permitted_opens[i].listen_port == listen_port) {
1.99 markus 2978: return connect_to(
1.73 markus 2979: permitted_opens[i].host_to_connect,
1.276 djm 2980: permitted_opens[i].port_to_connect, ctype, rname);
2981: }
2982: }
1.74 markus 2983: error("WARNING: Server requests forwarding for unknown listen_port %d",
2984: listen_port);
1.276 djm 2985: return NULL;
1.73 markus 2986: }
2987:
1.99 markus 2988: /* Check if connecting to that port is permitted and connect. */
1.276 djm 2989: Channel *
2990: channel_connect_to(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 2991: {
1.257 dtucker 2992: int i, permit, permit_adm = 1;
1.99 markus 2993:
2994: permit = all_opens_permitted;
2995: if (!permit) {
2996: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2997: if (permitted_opens[i].host_to_connect != NULL &&
2998: permitted_opens[i].port_to_connect == port &&
1.99 markus 2999: strcmp(permitted_opens[i].host_to_connect, host) == 0)
3000: permit = 1;
1.257 dtucker 3001: }
1.99 markus 3002:
1.257 dtucker 3003: if (num_adm_permitted_opens > 0) {
3004: permit_adm = 0;
3005: for (i = 0; i < num_adm_permitted_opens; i++)
3006: if (permitted_adm_opens[i].host_to_connect != NULL &&
3007: permitted_adm_opens[i].port_to_connect == port &&
3008: strcmp(permitted_adm_opens[i].host_to_connect, host)
3009: == 0)
3010: permit_adm = 1;
1.99 markus 3011: }
1.257 dtucker 3012:
3013: if (!permit || !permit_adm) {
1.188 itojun 3014: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3015: "but the request was denied.", host, port);
1.276 djm 3016: return NULL;
1.99 markus 3017: }
1.276 djm 3018: return connect_to(host, port, ctype, rname);
1.204 djm 3019: }
3020:
3021: void
3022: channel_send_window_changes(void)
3023: {
1.209 avsm 3024: u_int i;
1.204 djm 3025: struct winsize ws;
3026:
3027: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3028: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3029: channels[i]->type != SSH_CHANNEL_OPEN)
3030: continue;
3031: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3032: continue;
3033: channel_request_start(i, "window-change", 0);
1.238 deraadt 3034: packet_put_int((u_int)ws.ws_col);
3035: packet_put_int((u_int)ws.ws_row);
3036: packet_put_int((u_int)ws.ws_xpixel);
3037: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3038: packet_send();
3039: }
1.99 markus 3040: }
3041:
1.121 markus 3042: /* -- X11 forwarding */
1.1 deraadt 3043:
1.27 markus 3044: /*
3045: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3046: * Returns 0 and a suitable display number for the DISPLAY variable
3047: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3048: */
1.141 stevesk 3049: int
1.163 stevesk 3050: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3051: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3052: {
1.149 markus 3053: Channel *nc = NULL;
1.31 markus 3054: int display_number, sock;
3055: u_short port;
1.35 markus 3056: struct addrinfo hints, *ai, *aitop;
3057: char strport[NI_MAXSERV];
3058: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3059:
1.224 markus 3060: if (chanids == NULL)
3061: return -1;
3062:
1.33 markus 3063: for (display_number = x11_display_offset;
1.148 deraadt 3064: display_number < MAX_DISPLAYS;
3065: display_number++) {
1.25 markus 3066: port = 6000 + display_number;
1.35 markus 3067: memset(&hints, 0, sizeof(hints));
3068: hints.ai_family = IPv4or6;
1.163 stevesk 3069: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3070: hints.ai_socktype = SOCK_STREAM;
3071: snprintf(strport, sizeof strport, "%d", port);
3072: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3073: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3074: return -1;
1.25 markus 3075: }
1.35 markus 3076: for (ai = aitop; ai; ai = ai->ai_next) {
3077: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3078: continue;
1.297 ! reyk 3079: sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
! 3080: ai->ai_protocol, channel_rdomain);
1.35 markus 3081: if (sock < 0) {
3082: error("socket: %.100s", strerror(errno));
1.203 markus 3083: freeaddrinfo(aitop);
1.141 stevesk 3084: return -1;
1.35 markus 3085: }
1.226 djm 3086: channel_set_reuseaddr(sock);
1.35 markus 3087: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3088: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3089: close(sock);
1.183 itojun 3090:
1.35 markus 3091: for (n = 0; n < num_socks; n++) {
3092: close(socks[n]);
3093: }
3094: num_socks = 0;
3095: break;
3096: }
3097: socks[num_socks++] = sock;
3098: if (num_socks == NUM_SOCKS)
3099: break;
1.25 markus 3100: }
1.83 stevesk 3101: freeaddrinfo(aitop);
1.35 markus 3102: if (num_socks > 0)
3103: break;
1.25 markus 3104: }
3105: if (display_number >= MAX_DISPLAYS) {
3106: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3107: return -1;
1.25 markus 3108: }
3109: /* Start listening for connections on the socket. */
1.35 markus 3110: for (n = 0; n < num_socks; n++) {
3111: sock = socks[n];
1.199 markus 3112: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3113: error("listen: %.100s", strerror(errno));
3114: close(sock);
1.141 stevesk 3115: return -1;
1.35 markus 3116: }
1.25 markus 3117: }
1.35 markus 3118:
3119: /* Allocate a channel for each socket. */
1.242 djm 3120: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3121: for (n = 0; n < num_socks; n++) {
3122: sock = socks[n];
1.149 markus 3123: nc = channel_new("x11 listener",
1.51 markus 3124: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3125: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3126: 0, "X11 inet listener", 1);
1.167 markus 3127: nc->single_connection = single_connection;
1.224 markus 3128: (*chanids)[n] = nc->self;
1.35 markus 3129: }
1.224 markus 3130: (*chanids)[n] = -1;
1.1 deraadt 3131:
1.141 stevesk 3132: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3133: *display_numberp = display_number;
3134: return (0);
1.1 deraadt 3135: }
3136:
1.127 itojun 3137: static int
1.77 markus 3138: connect_local_xsocket(u_int dnr)
1.1 deraadt 3139: {
1.25 markus 3140: int sock;
3141: struct sockaddr_un addr;
3142:
1.147 stevesk 3143: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3144: if (sock < 0)
3145: error("socket: %.100s", strerror(errno));
3146: memset(&addr, 0, sizeof(addr));
3147: addr.sun_family = AF_UNIX;
3148: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3149: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3150: return sock;
3151: close(sock);
1.25 markus 3152: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3153: return -1;
1.1 deraadt 3154: }
3155:
1.51 markus 3156: int
3157: x11_connect_display(void)
1.1 deraadt 3158: {
1.248 deraadt 3159: u_int display_number;
1.25 markus 3160: const char *display;
1.51 markus 3161: char buf[1024], *cp;
1.35 markus 3162: struct addrinfo hints, *ai, *aitop;
3163: char strport[NI_MAXSERV];
1.248 deraadt 3164: int gaierr, sock = 0;
1.25 markus 3165:
3166: /* Try to open a socket for the local X server. */
3167: display = getenv("DISPLAY");
3168: if (!display) {
3169: error("DISPLAY not set.");
1.51 markus 3170: return -1;
1.25 markus 3171: }
1.27 markus 3172: /*
3173: * Now we decode the value of the DISPLAY variable and make a
3174: * connection to the real X server.
3175: */
3176:
3177: /*
3178: * Check if it is a unix domain socket. Unix domain displays are in
3179: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3180: */
1.25 markus 3181: if (strncmp(display, "unix:", 5) == 0 ||
3182: display[0] == ':') {
3183: /* Connect to the unix domain socket. */
1.248 deraadt 3184: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3185: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3186: display);
1.51 markus 3187: return -1;
1.25 markus 3188: }
3189: /* Create a socket. */
3190: sock = connect_local_xsocket(display_number);
3191: if (sock < 0)
1.51 markus 3192: return -1;
1.25 markus 3193:
3194: /* OK, we now have a connection to the display. */
1.51 markus 3195: return sock;
1.25 markus 3196: }
1.27 markus 3197: /*
3198: * Connect to an inet socket. The DISPLAY value is supposedly
3199: * hostname:d[.s], where hostname may also be numeric IP address.
3200: */
1.145 stevesk 3201: strlcpy(buf, display, sizeof(buf));
1.25 markus 3202: cp = strchr(buf, ':');
3203: if (!cp) {
3204: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3205: return -1;
1.25 markus 3206: }
3207: *cp = 0;
1.27 markus 3208: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 3209: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 3210: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3211: display);
1.51 markus 3212: return -1;
1.25 markus 3213: }
1.35 markus 3214:
3215: /* Look up the host address */
3216: memset(&hints, 0, sizeof(hints));
3217: hints.ai_family = IPv4or6;
3218: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 3219: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 3220: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3221: error("%.100s: unknown host. (%s)", buf,
3222: ssh_gai_strerror(gaierr));
1.51 markus 3223: return -1;
1.25 markus 3224: }
1.35 markus 3225: for (ai = aitop; ai; ai = ai->ai_next) {
3226: /* Create a socket. */
1.297 ! reyk 3227: sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
! 3228: ai->ai_protocol, channel_rdomain);
1.35 markus 3229: if (sock < 0) {
1.194 markus 3230: debug2("socket: %.100s", strerror(errno));
1.41 markus 3231: continue;
3232: }
3233: /* Connect it to the display. */
3234: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 3235: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 3236: 6000 + display_number, strerror(errno));
3237: close(sock);
3238: continue;
3239: }
3240: /* Success */
3241: break;
1.35 markus 3242: }
3243: freeaddrinfo(aitop);
3244: if (!ai) {
1.248 deraadt 3245: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3246: strerror(errno));
1.51 markus 3247: return -1;
1.25 markus 3248: }
1.162 stevesk 3249: set_nodelay(sock);
1.51 markus 3250: return sock;
3251: }
3252:
3253: /*
3254: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3255: * the remote channel number. We should do whatever we want, and respond
3256: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3257: */
3258:
1.259 stevesk 3259: /* ARGSUSED */
1.51 markus 3260: void
1.154 markus 3261: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3262: {
1.113 markus 3263: Channel *c = NULL;
3264: int remote_id, sock = 0;
1.51 markus 3265: char *remote_host;
1.25 markus 3266:
1.113 markus 3267: debug("Received X11 open request.");
1.51 markus 3268:
1.113 markus 3269: remote_id = packet_get_int();
1.121 markus 3270:
3271: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3272: remote_host = packet_get_string(NULL);
1.51 markus 3273: } else {
3274: remote_host = xstrdup("unknown (remote did not supply name)");
3275: }
1.152 markus 3276: packet_check_eom();
1.25 markus 3277:
1.51 markus 3278: /* Obtain a connection to the real X display. */
3279: sock = x11_connect_display();
1.113 markus 3280: if (sock != -1) {
3281: /* Allocate a channel for this connection. */
3282: c = channel_new("connected x11 socket",
3283: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3284: remote_host, 1);
1.167 markus 3285: c->remote_id = remote_id;
3286: c->force_drain = 1;
1.113 markus 3287: }
1.190 markus 3288: xfree(remote_host);
1.113 markus 3289: if (c == NULL) {
1.51 markus 3290: /* Send refusal to the remote host. */
3291: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3292: packet_put_int(remote_id);
1.51 markus 3293: } else {
3294: /* Send a confirmation to the remote host. */
3295: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3296: packet_put_int(remote_id);
3297: packet_put_int(c->self);
1.51 markus 3298: }
1.113 markus 3299: packet_send();
1.72 markus 3300: }
3301:
3302: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 3303: /* ARGSUSED */
1.72 markus 3304: void
1.154 markus 3305: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3306: {
3307: int rchan = packet_get_int();
1.180 deraadt 3308:
1.143 deraadt 3309: switch (type) {
1.72 markus 3310: case SSH_SMSG_AGENT_OPEN:
3311: error("Warning: ssh server tried agent forwarding.");
3312: break;
3313: case SSH_SMSG_X11_OPEN:
3314: error("Warning: ssh server tried X11 forwarding.");
3315: break;
3316: default:
1.154 markus 3317: error("deny_input_open: type %d", type);
1.72 markus 3318: break;
3319: }
1.230 stevesk 3320: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3321: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3322: packet_put_int(rchan);
3323: packet_send();
1.1 deraadt 3324: }
3325:
1.27 markus 3326: /*
3327: * Requests forwarding of X11 connections, generates fake authentication
3328: * data, and enables authentication spoofing.
1.121 markus 3329: * This should be called in the client only.
1.27 markus 3330: */
1.49 markus 3331: void
1.215 djm 3332: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.51 markus 3333: const char *proto, const char *data)
1.1 deraadt 3334: {
1.77 markus 3335: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3336: u_int i, value;
1.25 markus 3337: char *new_data;
3338: int screen_number;
3339: const char *cp;
1.207 avsm 3340: u_int32_t rnd = 0;
1.25 markus 3341:
1.220 markus 3342: if (x11_saved_display == NULL)
3343: x11_saved_display = xstrdup(disp);
3344: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3345: error("x11_request_forwarding_with_spoofing: different "
3346: "$DISPLAY already forwarded");
3347: return;
3348: }
3349:
1.266 djm 3350: cp = strchr(disp, ':');
1.25 markus 3351: if (cp)
3352: cp = strchr(cp, '.');
3353: if (cp)
1.245 deraadt 3354: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3355: else
3356: screen_number = 0;
3357:
1.219 djm 3358: if (x11_saved_proto == NULL) {
3359: /* Save protocol name. */
3360: x11_saved_proto = xstrdup(proto);
3361: /*
1.221 djm 3362: * Extract real authentication data and generate fake data
1.219 djm 3363: * of the same length.
3364: */
3365: x11_saved_data = xmalloc(data_len);
3366: x11_fake_data = xmalloc(data_len);
3367: for (i = 0; i < data_len; i++) {
3368: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3369: fatal("x11_request_forwarding: bad "
3370: "authentication data: %.100s", data);
3371: if (i % 4 == 0)
3372: rnd = arc4random();
3373: x11_saved_data[i] = value;
3374: x11_fake_data[i] = rnd & 0xff;
3375: rnd >>= 8;
3376: }
3377: x11_saved_data_len = data_len;
3378: x11_fake_data_len = data_len;
1.25 markus 3379: }
3380:
3381: /* Convert the fake data into hex. */
1.219 djm 3382: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3383:
3384: /* Send the request packet. */
1.51 markus 3385: if (compat20) {
3386: channel_request_start(client_session_id, "x11-req", 0);
3387: packet_put_char(0); /* XXX bool single connection */
3388: } else {
3389: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3390: }
3391: packet_put_cstring(proto);
3392: packet_put_cstring(new_data);
1.25 markus 3393: packet_put_int(screen_number);
3394: packet_send();
3395: packet_write_wait();
3396: xfree(new_data);
1.1 deraadt 3397: }
3398:
1.121 markus 3399:
3400: /* -- agent forwarding */
3401:
1.1 deraadt 3402: /* Sends a message to the server to request authentication fd forwarding. */
3403:
1.49 markus 3404: void
1.142 itojun 3405: auth_request_forwarding(void)
1.1 deraadt 3406: {
1.25 markus 3407: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3408: packet_send();
3409: packet_write_wait();
1.1 deraadt 3410: }
![[BACK]](/icons/back.gif){kind=icon}
Return to channels.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh