Annotation of src/usr.bin/ssh/channels.c, Revision 1.299
1.299 ! markus 1: /* $OpenBSD: channels.c,v 1.298 2009/11/10 04:30:44 dtucker 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>
1.298 dtucker 53: #include <fcntl.h>
1.255 stevesk 54: #include <netdb.h>
1.263 stevesk 55: #include <stdio.h>
1.262 stevesk 56: #include <stdlib.h>
1.260 stevesk 57: #include <string.h>
1.233 stevesk 58: #include <termios.h>
1.256 stevesk 59: #include <unistd.h>
1.265 deraadt 60: #include <stdarg.h>
1.1 deraadt 61:
1.265 deraadt 62: #include "xmalloc.h"
1.1 deraadt 63: #include "ssh.h"
1.82 markus 64: #include "ssh1.h"
65: #include "ssh2.h"
1.1 deraadt 66: #include "packet.h"
1.82 markus 67: #include "log.h"
68: #include "misc.h"
1.265 deraadt 69: #include "buffer.h"
1.14 markus 70: #include "channels.h"
71: #include "compat.h"
1.82 markus 72: #include "canohost.h"
1.64 markus 73: #include "key.h"
74: #include "authfd.h"
1.147 stevesk 75: #include "pathnames.h"
1.1 deraadt 76:
1.121 markus 77: /* -- channel core */
1.12 markus 78:
1.27 markus 79: /*
80: * Pointer to an array containing all allocated channels. The array is
81: * dynamically extended as needed.
82: */
1.113 markus 83: static Channel **channels = NULL;
1.1 deraadt 84:
1.27 markus 85: /*
86: * Size of the channel array. All slots of the array must always be
1.113 markus 87: * initialized (at least the type field); unused slots set to NULL
1.27 markus 88: */
1.209 avsm 89: static u_int channels_alloc = 0;
1.1 deraadt 90:
1.27 markus 91: /*
92: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 93: * updated in channel_new.
1.27 markus 94: */
1.84 markus 95: static int channel_max_fd = 0;
1.1 deraadt 96:
97:
1.121 markus 98: /* -- tcp forwarding */
1.1 deraadt 99:
1.27 markus 100: /*
101: * Data structure for storing which hosts are permitted for forward requests.
102: * The local sides of any remote forwards are stored in this array to prevent
103: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
104: * network (which might be behind a firewall).
105: */
1.25 markus 106: typedef struct {
1.41 markus 107: char *host_to_connect; /* Connect to 'host'. */
108: u_short port_to_connect; /* Connect to 'port'. */
109: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 110: } ForwardPermission;
111:
1.257 dtucker 112: /* List of all permitted host/port pairs to connect by the user. */
1.1 deraadt 113: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 114:
1.257 dtucker 115: /* List of all permitted host/port pairs to connect by the admin. */
116: static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
117:
118: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 119: static int num_permitted_opens = 0;
1.257 dtucker 120:
121: /* Number of permitted host/port pair in the array permitted by the admin. */
122: static int num_adm_permitted_opens = 0;
123:
1.27 markus 124: /*
125: * If this is true, all opens are permitted. This is the case on the server
126: * on which we have to trust the client anyway, and the user could do
127: * anything after logging in anyway.
128: */
1.1 deraadt 129: static int all_opens_permitted = 0;
130:
1.121 markus 131:
132: /* -- X11 forwarding */
133:
134: /* Maximum number of fake X11 displays to try. */
135: #define MAX_DISPLAYS 1000
136:
1.219 djm 137: /* Saved X11 local (client) display. */
138: static char *x11_saved_display = NULL;
139:
1.121 markus 140: /* Saved X11 authentication protocol name. */
141: static char *x11_saved_proto = NULL;
142:
143: /* Saved X11 authentication data. This is the real data. */
144: static char *x11_saved_data = NULL;
145: static u_int x11_saved_data_len = 0;
146:
147: /*
148: * Fake X11 authentication data. This is what the server will be sending us;
149: * we should replace any occurrences of this by the real data.
150: */
1.240 deraadt 151: static u_char *x11_fake_data = NULL;
1.121 markus 152: static u_int x11_fake_data_len;
153:
154:
155: /* -- agent forwarding */
156:
157: #define NUM_SOCKS 10
158:
1.82 markus 159: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 160: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 161:
1.297 reyk 162: /* Set the routing domain a.k.a. VRF */
163: static int channel_rdomain = -1;
164:
1.121 markus 165: /* helper */
1.127 itojun 166: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 167:
1.276 djm 168: /* non-blocking connect helpers */
169: static int connect_next(struct channel_connect *);
170: static void channel_connect_ctx_free(struct channel_connect *);
171:
1.121 markus 172: /* -- channel core */
1.41 markus 173:
174: Channel *
1.229 markus 175: channel_by_id(int id)
1.41 markus 176: {
177: Channel *c;
1.113 markus 178:
1.209 avsm 179: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 180: logit("channel_by_id: %d: bad id", id);
1.41 markus 181: return NULL;
182: }
1.113 markus 183: c = channels[id];
184: if (c == NULL) {
1.229 markus 185: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 186: return NULL;
187: }
188: return c;
1.55 markus 189: }
190:
1.27 markus 191: /*
1.229 markus 192: * Returns the channel if it is allowed to receive protocol messages.
193: * Private channels, like listening sockets, may not receive messages.
194: */
195: Channel *
196: channel_lookup(int id)
197: {
198: Channel *c;
199:
200: if ((c = channel_by_id(id)) == NULL)
201: return (NULL);
202:
1.237 deraadt 203: switch (c->type) {
1.229 markus 204: case SSH_CHANNEL_X11_OPEN:
205: case SSH_CHANNEL_LARVAL:
206: case SSH_CHANNEL_CONNECTING:
207: case SSH_CHANNEL_DYNAMIC:
208: case SSH_CHANNEL_OPENING:
209: case SSH_CHANNEL_OPEN:
210: case SSH_CHANNEL_INPUT_DRAINING:
211: case SSH_CHANNEL_OUTPUT_DRAINING:
212: return (c);
213: }
214: logit("Non-public channel %d, type %d.", id, c->type);
215: return (NULL);
216: }
217:
218: /*
1.55 markus 219: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 220: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 221: */
1.127 itojun 222: static void
1.71 markus 223: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 224: int extusage, int nonblock, int is_tty)
1.1 deraadt 225: {
1.25 markus 226: /* Update the maximum file descriptor value. */
1.84 markus 227: channel_max_fd = MAX(channel_max_fd, rfd);
228: channel_max_fd = MAX(channel_max_fd, wfd);
229: channel_max_fd = MAX(channel_max_fd, efd);
230:
1.298 dtucker 231: if (rfd != -1)
232: fcntl(rfd, F_SETFD, FD_CLOEXEC);
233: if (wfd != -1 && wfd != rfd)
234: fcntl(wfd, F_SETFD, FD_CLOEXEC);
235: if (efd != -1 && efd != rfd && efd != wfd)
236: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 237:
1.52 markus 238: c->rfd = rfd;
239: c->wfd = wfd;
240: c->sock = (rfd == wfd) ? rfd : -1;
1.204 djm 241: c->ctl_fd = -1; /* XXX: set elsewhere */
1.52 markus 242: c->efd = efd;
243: c->extended_usage = extusage;
1.71 markus 244:
1.282 dtucker 245: if ((c->isatty = is_tty) != 0)
1.194 markus 246: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 247:
1.71 markus 248: /* enable nonblocking mode */
249: if (nonblock) {
250: if (rfd != -1)
251: set_nonblock(rfd);
252: if (wfd != -1)
253: set_nonblock(wfd);
254: if (efd != -1)
255: set_nonblock(efd);
256: }
1.52 markus 257: }
258:
259: /*
260: * Allocate a new channel object and set its type and socket. This will cause
261: * remote_name to be freed.
262: */
1.113 markus 263: Channel *
1.52 markus 264: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 265: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 266: {
1.209 avsm 267: int found;
268: u_int i;
1.52 markus 269: Channel *c;
1.25 markus 270:
271: /* Do initial allocation if this is the first call. */
272: if (channels_alloc == 0) {
273: channels_alloc = 10;
1.242 djm 274: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 275: for (i = 0; i < channels_alloc; i++)
1.113 markus 276: channels[i] = NULL;
1.25 markus 277: }
278: /* Try to find a free slot where to put the new channel. */
279: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 280: if (channels[i] == NULL) {
1.25 markus 281: /* Found a free slot. */
1.209 avsm 282: found = (int)i;
1.25 markus 283: break;
284: }
1.209 avsm 285: if (found < 0) {
1.27 markus 286: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 287: found = channels_alloc;
1.179 markus 288: if (channels_alloc > 10000)
289: fatal("channel_new: internal error: channels_alloc %d "
290: "too big.", channels_alloc);
1.243 djm 291: channels = xrealloc(channels, channels_alloc + 10,
292: sizeof(Channel *));
1.195 markus 293: channels_alloc += 10;
1.70 markus 294: debug2("channel: expanding %d", channels_alloc);
1.25 markus 295: for (i = found; i < channels_alloc; i++)
1.113 markus 296: channels[i] = NULL;
1.25 markus 297: }
1.113 markus 298: /* Initialize and return new channel. */
1.242 djm 299: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 300: buffer_init(&c->input);
301: buffer_init(&c->output);
1.41 markus 302: buffer_init(&c->extended);
1.293 djm 303: c->path = NULL;
1.159 markus 304: c->ostate = CHAN_OUTPUT_OPEN;
305: c->istate = CHAN_INPUT_OPEN;
306: c->flags = 0;
1.281 djm 307: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 308: c->self = found;
309: c->type = type;
1.41 markus 310: c->ctype = ctype;
1.51 markus 311: c->local_window = window;
312: c->local_window_max = window;
313: c->local_consumed = 0;
314: c->local_maxpacket = maxpack;
1.25 markus 315: c->remote_id = -1;
1.190 markus 316: c->remote_name = xstrdup(remote_name);
1.41 markus 317: c->remote_window = 0;
318: c->remote_maxpacket = 0;
1.133 markus 319: c->force_drain = 0;
1.149 markus 320: c->single_connection = 0;
1.131 markus 321: c->detach_user = NULL;
1.225 djm 322: c->detach_close = 0;
1.275 djm 323: c->open_confirm = NULL;
324: c->open_confirm_ctx = NULL;
1.65 markus 325: c->input_filter = NULL;
1.231 reyk 326: c->output_filter = NULL;
1.280 djm 327: c->filter_ctx = NULL;
328: c->filter_cleanup = NULL;
1.299 ! markus 329: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 330: TAILQ_INIT(&c->status_confirms);
1.25 markus 331: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 332: return c;
1.1 deraadt 333: }
1.52 markus 334:
1.132 markus 335: static int
336: channel_find_maxfd(void)
337: {
1.209 avsm 338: u_int i;
339: int max = 0;
1.132 markus 340: Channel *c;
341:
342: for (i = 0; i < channels_alloc; i++) {
343: c = channels[i];
344: if (c != NULL) {
345: max = MAX(max, c->rfd);
346: max = MAX(max, c->wfd);
347: max = MAX(max, c->efd);
348: }
349: }
350: return max;
351: }
352:
353: int
354: channel_close_fd(int *fdp)
355: {
356: int ret = 0, fd = *fdp;
357:
358: if (fd != -1) {
359: ret = close(fd);
360: *fdp = -1;
361: if (fd == channel_max_fd)
362: channel_max_fd = channel_find_maxfd();
363: }
364: return ret;
365: }
366:
1.52 markus 367: /* Close all channel fd/socket. */
1.127 itojun 368: static void
1.52 markus 369: channel_close_fds(Channel *c)
370: {
1.204 djm 371: debug3("channel %d: close_fds r %d w %d e %d c %d",
372: c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
1.118 markus 373:
1.132 markus 374: channel_close_fd(&c->sock);
1.204 djm 375: channel_close_fd(&c->ctl_fd);
1.132 markus 376: channel_close_fd(&c->rfd);
377: channel_close_fd(&c->wfd);
378: channel_close_fd(&c->efd);
1.121 markus 379: }
380:
381: /* Free the channel and close its fd/socket. */
382: void
383: channel_free(Channel *c)
384: {
385: char *s;
1.209 avsm 386: u_int i, n;
1.275 djm 387: struct channel_confirm *cc;
1.121 markus 388:
389: for (n = 0, i = 0; i < channels_alloc; i++)
390: if (channels[i])
391: n++;
1.209 avsm 392: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 393: c->remote_name ? c->remote_name : "???", n);
394:
395: s = channel_open_message();
1.194 markus 396: debug3("channel %d: status: %s", c->self, s);
1.121 markus 397: xfree(s);
398:
399: if (c->sock != -1)
400: shutdown(c->sock, SHUT_RDWR);
1.204 djm 401: if (c->ctl_fd != -1)
402: shutdown(c->ctl_fd, SHUT_RDWR);
1.121 markus 403: channel_close_fds(c);
404: buffer_free(&c->input);
405: buffer_free(&c->output);
406: buffer_free(&c->extended);
407: if (c->remote_name) {
408: xfree(c->remote_name);
409: c->remote_name = NULL;
410: }
1.293 djm 411: if (c->path) {
412: xfree(c->path);
413: c->path = NULL;
414: }
1.275 djm 415: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
416: if (cc->abandon_cb != NULL)
417: cc->abandon_cb(c, cc->ctx);
418: TAILQ_REMOVE(&c->status_confirms, cc, entry);
419: bzero(cc, sizeof(*cc));
420: xfree(cc);
421: }
1.280 djm 422: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
423: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 424: channels[c->self] = NULL;
425: xfree(c);
426: }
427:
428: void
1.126 markus 429: channel_free_all(void)
1.121 markus 430: {
1.209 avsm 431: u_int i;
1.121 markus 432:
1.126 markus 433: for (i = 0; i < channels_alloc; i++)
434: if (channels[i] != NULL)
435: channel_free(channels[i]);
1.131 markus 436: }
437:
1.121 markus 438: /*
439: * Closes the sockets/fds of all channels. This is used to close extra file
440: * descriptors after a fork.
441: */
442: void
1.142 itojun 443: channel_close_all(void)
1.121 markus 444: {
1.209 avsm 445: u_int i;
1.121 markus 446:
447: for (i = 0; i < channels_alloc; i++)
448: if (channels[i] != NULL)
449: channel_close_fds(channels[i]);
450: }
451:
452: /*
1.131 markus 453: * Stop listening to channels.
454: */
455: void
456: channel_stop_listening(void)
457: {
1.209 avsm 458: u_int i;
1.131 markus 459: Channel *c;
460:
461: for (i = 0; i < channels_alloc; i++) {
462: c = channels[i];
463: if (c != NULL) {
464: switch (c->type) {
465: case SSH_CHANNEL_AUTH_SOCKET:
466: case SSH_CHANNEL_PORT_LISTENER:
467: case SSH_CHANNEL_RPORT_LISTENER:
468: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 469: channel_close_fd(&c->sock);
1.131 markus 470: channel_free(c);
471: break;
472: }
473: }
474: }
475: }
476:
477: /*
1.121 markus 478: * Returns true if no channel has too much buffered data, and false if one or
479: * more channel is overfull.
480: */
481: int
1.142 itojun 482: channel_not_very_much_buffered_data(void)
1.121 markus 483: {
484: u_int i;
485: Channel *c;
486:
487: for (i = 0; i < channels_alloc; i++) {
488: c = channels[i];
489: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 490: #if 0
491: if (!compat20 &&
492: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 493: debug2("channel %d: big input buffer %d",
1.121 markus 494: c->self, buffer_len(&c->input));
495: return 0;
496: }
1.136 markus 497: #endif
1.121 markus 498: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 499: debug2("channel %d: big output buffer %u > %u",
1.136 markus 500: c->self, buffer_len(&c->output),
501: packet_get_maxsize());
1.121 markus 502: return 0;
503: }
504: }
505: }
506: return 1;
507: }
508:
509: /* Returns true if any channel is still open. */
510: int
1.142 itojun 511: channel_still_open(void)
1.121 markus 512: {
1.209 avsm 513: u_int i;
1.121 markus 514: Channel *c;
515:
516: for (i = 0; i < channels_alloc; i++) {
517: c = channels[i];
518: if (c == NULL)
519: continue;
520: switch (c->type) {
521: case SSH_CHANNEL_X11_LISTENER:
522: case SSH_CHANNEL_PORT_LISTENER:
523: case SSH_CHANNEL_RPORT_LISTENER:
524: case SSH_CHANNEL_CLOSED:
525: case SSH_CHANNEL_AUTH_SOCKET:
526: case SSH_CHANNEL_DYNAMIC:
527: case SSH_CHANNEL_CONNECTING:
528: case SSH_CHANNEL_ZOMBIE:
529: continue;
530: case SSH_CHANNEL_LARVAL:
531: if (!compat20)
532: fatal("cannot happen: SSH_CHANNEL_LARVAL");
533: continue;
534: case SSH_CHANNEL_OPENING:
535: case SSH_CHANNEL_OPEN:
536: case SSH_CHANNEL_X11_OPEN:
537: return 1;
538: case SSH_CHANNEL_INPUT_DRAINING:
539: case SSH_CHANNEL_OUTPUT_DRAINING:
540: if (!compat13)
541: fatal("cannot happen: OUT_DRAIN");
542: return 1;
543: default:
544: fatal("channel_still_open: bad channel type %d", c->type);
545: /* NOTREACHED */
546: }
547: }
548: return 0;
549: }
550:
551: /* Returns the id of an open channel suitable for keepaliving */
552: int
1.142 itojun 553: channel_find_open(void)
1.121 markus 554: {
1.209 avsm 555: u_int i;
1.121 markus 556: Channel *c;
557:
558: for (i = 0; i < channels_alloc; i++) {
559: c = channels[i];
1.206 djm 560: if (c == NULL || c->remote_id < 0)
1.121 markus 561: continue;
562: switch (c->type) {
563: case SSH_CHANNEL_CLOSED:
564: case SSH_CHANNEL_DYNAMIC:
565: case SSH_CHANNEL_X11_LISTENER:
566: case SSH_CHANNEL_PORT_LISTENER:
567: case SSH_CHANNEL_RPORT_LISTENER:
568: case SSH_CHANNEL_OPENING:
569: case SSH_CHANNEL_CONNECTING:
570: case SSH_CHANNEL_ZOMBIE:
571: continue;
572: case SSH_CHANNEL_LARVAL:
573: case SSH_CHANNEL_AUTH_SOCKET:
574: case SSH_CHANNEL_OPEN:
575: case SSH_CHANNEL_X11_OPEN:
576: return i;
577: case SSH_CHANNEL_INPUT_DRAINING:
578: case SSH_CHANNEL_OUTPUT_DRAINING:
579: if (!compat13)
580: fatal("cannot happen: OUT_DRAIN");
581: return i;
582: default:
583: fatal("channel_find_open: bad channel type %d", c->type);
584: /* NOTREACHED */
585: }
586: }
587: return -1;
588: }
589:
590:
591: /*
592: * Returns a message describing the currently open forwarded connections,
593: * suitable for sending to the client. The message contains crlf pairs for
594: * newlines.
595: */
596: char *
1.142 itojun 597: channel_open_message(void)
1.121 markus 598: {
599: Buffer buffer;
600: Channel *c;
601: char buf[1024], *cp;
1.209 avsm 602: u_int i;
1.121 markus 603:
604: buffer_init(&buffer);
605: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
606: buffer_append(&buffer, buf, strlen(buf));
607: for (i = 0; i < channels_alloc; i++) {
608: c = channels[i];
609: if (c == NULL)
610: continue;
611: switch (c->type) {
612: case SSH_CHANNEL_X11_LISTENER:
613: case SSH_CHANNEL_PORT_LISTENER:
614: case SSH_CHANNEL_RPORT_LISTENER:
615: case SSH_CHANNEL_CLOSED:
616: case SSH_CHANNEL_AUTH_SOCKET:
617: case SSH_CHANNEL_ZOMBIE:
618: continue;
619: case SSH_CHANNEL_LARVAL:
620: case SSH_CHANNEL_OPENING:
621: case SSH_CHANNEL_CONNECTING:
622: case SSH_CHANNEL_DYNAMIC:
623: case SSH_CHANNEL_OPEN:
624: case SSH_CHANNEL_X11_OPEN:
625: case SSH_CHANNEL_INPUT_DRAINING:
626: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 627: snprintf(buf, sizeof buf,
628: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
1.121 markus 629: c->self, c->remote_name,
630: c->type, c->remote_id,
631: c->istate, buffer_len(&c->input),
632: c->ostate, buffer_len(&c->output),
1.204 djm 633: c->rfd, c->wfd, c->ctl_fd);
1.121 markus 634: buffer_append(&buffer, buf, strlen(buf));
635: continue;
636: default:
637: fatal("channel_open_message: bad channel type %d", c->type);
638: /* NOTREACHED */
639: }
640: }
641: buffer_append(&buffer, "\0", 1);
642: cp = xstrdup(buffer_ptr(&buffer));
643: buffer_free(&buffer);
644: return cp;
645: }
646:
647: void
648: channel_send_open(int id)
649: {
650: Channel *c = channel_lookup(id);
1.180 deraadt 651:
1.121 markus 652: if (c == NULL) {
1.188 itojun 653: logit("channel_send_open: %d: bad id", id);
1.121 markus 654: return;
655: }
1.184 markus 656: debug2("channel %d: send open", id);
1.121 markus 657: packet_start(SSH2_MSG_CHANNEL_OPEN);
658: packet_put_cstring(c->ctype);
659: packet_put_int(c->self);
660: packet_put_int(c->local_window);
661: packet_put_int(c->local_maxpacket);
662: packet_send();
663: }
664:
665: void
1.184 markus 666: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 667: {
1.184 markus 668: Channel *c = channel_lookup(id);
1.180 deraadt 669:
1.121 markus 670: if (c == NULL) {
1.188 itojun 671: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 672: return;
673: }
1.204 djm 674: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 675: packet_start(SSH2_MSG_CHANNEL_REQUEST);
676: packet_put_int(c->remote_id);
677: packet_put_cstring(service);
678: packet_put_char(wantconfirm);
679: }
1.241 deraadt 680:
1.121 markus 681: void
1.275 djm 682: channel_register_status_confirm(int id, channel_confirm_cb *cb,
683: channel_confirm_abandon_cb *abandon_cb, void *ctx)
684: {
685: struct channel_confirm *cc;
686: Channel *c;
687:
688: if ((c = channel_lookup(id)) == NULL)
689: fatal("channel_register_expect: %d: bad id", id);
690:
691: cc = xmalloc(sizeof(*cc));
692: cc->cb = cb;
693: cc->abandon_cb = abandon_cb;
694: cc->ctx = ctx;
695: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
696: }
697:
698: void
699: channel_register_open_confirm(int id, channel_callback_fn *fn, void *ctx)
1.121 markus 700: {
701: Channel *c = channel_lookup(id);
1.180 deraadt 702:
1.121 markus 703: if (c == NULL) {
1.287 stevesk 704: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 705: return;
706: }
1.275 djm 707: c->open_confirm = fn;
708: c->open_confirm_ctx = ctx;
1.121 markus 709: }
1.241 deraadt 710:
1.121 markus 711: void
1.225 djm 712: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 713: {
1.229 markus 714: Channel *c = channel_by_id(id);
1.180 deraadt 715:
1.121 markus 716: if (c == NULL) {
1.188 itojun 717: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 718: return;
719: }
1.131 markus 720: c->detach_user = fn;
1.225 djm 721: c->detach_close = do_close;
1.121 markus 722: }
1.241 deraadt 723:
1.121 markus 724: void
725: channel_cancel_cleanup(int id)
726: {
1.229 markus 727: Channel *c = channel_by_id(id);
1.180 deraadt 728:
1.121 markus 729: if (c == NULL) {
1.188 itojun 730: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 731: return;
1.52 markus 732: }
1.131 markus 733: c->detach_user = NULL;
1.225 djm 734: c->detach_close = 0;
1.121 markus 735: }
1.241 deraadt 736:
1.121 markus 737: void
1.231 reyk 738: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 739: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 740: {
741: Channel *c = channel_lookup(id);
1.180 deraadt 742:
1.121 markus 743: if (c == NULL) {
1.188 itojun 744: logit("channel_register_filter: %d: bad id", id);
1.121 markus 745: return;
1.52 markus 746: }
1.231 reyk 747: c->input_filter = ifn;
748: c->output_filter = ofn;
1.279 djm 749: c->filter_ctx = ctx;
1.280 djm 750: c->filter_cleanup = cfn;
1.52 markus 751: }
752:
1.49 markus 753: void
1.121 markus 754: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 755: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 756: {
1.121 markus 757: Channel *c = channel_lookup(id);
1.180 deraadt 758:
1.121 markus 759: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
760: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 761: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 762: c->type = SSH_CHANNEL_OPEN;
1.168 markus 763: c->local_window = c->local_window_max = window_max;
1.121 markus 764: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
765: packet_put_int(c->remote_id);
766: packet_put_int(c->local_window);
767: packet_send();
1.1 deraadt 768: }
769:
1.27 markus 770: /*
1.41 markus 771: * 'channel_pre*' are called just before select() to add any bits relevant to
772: * channels in the select bitmasks.
773: */
774: /*
775: * 'channel_post*': perform any appropriate operations for channels which
776: * have events pending.
1.27 markus 777: */
1.237 deraadt 778: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 779: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
780: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
781:
1.259 stevesk 782: /* ARGSUSED */
1.127 itojun 783: static void
1.237 deraadt 784: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 785: {
786: FD_SET(c->sock, readset);
787: }
788:
1.259 stevesk 789: /* ARGSUSED */
1.127 itojun 790: static void
1.237 deraadt 791: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 792: {
793: debug3("channel %d: waiting for connection", c->self);
794: FD_SET(c->sock, writeset);
795: }
796:
1.127 itojun 797: static void
1.237 deraadt 798: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 799: {
800: if (buffer_len(&c->input) < packet_get_maxsize())
801: FD_SET(c->sock, readset);
802: if (buffer_len(&c->output) > 0)
803: FD_SET(c->sock, writeset);
804: }
1.1 deraadt 805:
1.127 itojun 806: static void
1.237 deraadt 807: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 808: {
1.157 markus 809: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 810:
1.44 markus 811: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 812: limit > 0 &&
1.250 djm 813: buffer_len(&c->input) < limit &&
814: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 815: FD_SET(c->rfd, readset);
816: if (c->ostate == CHAN_OUTPUT_OPEN ||
817: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
818: if (buffer_len(&c->output) > 0) {
819: FD_SET(c->wfd, writeset);
820: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 821: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 822: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
823: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 824: else
825: chan_obuf_empty(c);
1.44 markus 826: }
827: }
828: /** XXX check close conditions, too */
1.277 markus 829: if (compat20 && c->efd != -1 &&
830: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 831: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
832: buffer_len(&c->extended) > 0)
833: FD_SET(c->efd, writeset);
1.172 markus 834: else if (!(c->flags & CHAN_EOF_SENT) &&
835: c->extended_usage == CHAN_EXTENDED_READ &&
1.44 markus 836: buffer_len(&c->extended) < c->remote_window)
837: FD_SET(c->efd, readset);
838: }
1.204 djm 839: /* XXX: What about efd? races? */
1.208 deraadt 840: if (compat20 && c->ctl_fd != -1 &&
1.204 djm 841: c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
842: FD_SET(c->ctl_fd, readset);
1.44 markus 843: }
844:
1.259 stevesk 845: /* ARGSUSED */
1.127 itojun 846: static void
1.237 deraadt 847: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 848: {
849: if (buffer_len(&c->input) == 0) {
850: packet_start(SSH_MSG_CHANNEL_CLOSE);
851: packet_put_int(c->remote_id);
852: packet_send();
853: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 854: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 855: }
856: }
857:
1.259 stevesk 858: /* ARGSUSED */
1.127 itojun 859: static void
1.237 deraadt 860: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 861: {
862: if (buffer_len(&c->output) == 0)
1.113 markus 863: chan_mark_dead(c);
1.49 markus 864: else
1.41 markus 865: FD_SET(c->sock, writeset);
866: }
867:
868: /*
869: * This is a special state for X11 authentication spoofing. An opened X11
870: * connection (when authentication spoofing is being done) remains in this
871: * state until the first packet has been completely read. The authentication
872: * data in that packet is then substituted by the real data if it matches the
873: * fake data, and the channel is put into normal mode.
1.51 markus 874: * XXX All this happens at the client side.
1.121 markus 875: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 876: */
1.127 itojun 877: static int
1.121 markus 878: x11_open_helper(Buffer *b)
1.1 deraadt 879: {
1.77 markus 880: u_char *ucp;
881: u_int proto_len, data_len;
1.25 markus 882:
1.41 markus 883: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 884: if (buffer_len(b) < 12)
1.41 markus 885: return 0;
886:
887: /* Parse the lengths of variable-length fields. */
1.155 stevesk 888: ucp = buffer_ptr(b);
1.41 markus 889: if (ucp[0] == 0x42) { /* Byte order MSB first. */
890: proto_len = 256 * ucp[6] + ucp[7];
891: data_len = 256 * ucp[8] + ucp[9];
892: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
893: proto_len = ucp[6] + 256 * ucp[7];
894: data_len = ucp[8] + 256 * ucp[9];
895: } else {
1.194 markus 896: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 897: ucp[0]);
1.41 markus 898: return -1;
899: }
900:
901: /* Check if the whole packet is in buffer. */
1.121 markus 902: if (buffer_len(b) <
1.41 markus 903: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
904: return 0;
905:
906: /* Check if authentication protocol matches. */
907: if (proto_len != strlen(x11_saved_proto) ||
908: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 909: debug2("X11 connection uses different authentication protocol.");
1.41 markus 910: return -1;
911: }
912: /* Check if authentication data matches our fake data. */
913: if (data_len != x11_fake_data_len ||
914: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
915: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 916: debug2("X11 auth data does not match fake data.");
1.41 markus 917: return -1;
918: }
919: /* Check fake data length */
920: if (x11_fake_data_len != x11_saved_data_len) {
921: error("X11 fake_data_len %d != saved_data_len %d",
922: x11_fake_data_len, x11_saved_data_len);
923: return -1;
924: }
925: /*
926: * Received authentication protocol and data match
927: * our fake data. Substitute the fake data with real
928: * data.
929: */
930: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
931: x11_saved_data, x11_saved_data_len);
932: return 1;
933: }
934:
1.127 itojun 935: static void
1.237 deraadt 936: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 937: {
1.121 markus 938: int ret = x11_open_helper(&c->output);
1.180 deraadt 939:
1.41 markus 940: if (ret == 1) {
941: /* Start normal processing for the channel. */
942: c->type = SSH_CHANNEL_OPEN;
1.47 markus 943: channel_pre_open_13(c, readset, writeset);
1.41 markus 944: } else if (ret == -1) {
945: /*
946: * We have received an X11 connection that has bad
947: * authentication information.
948: */
1.188 itojun 949: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 950: buffer_clear(&c->input);
951: buffer_clear(&c->output);
1.132 markus 952: channel_close_fd(&c->sock);
1.41 markus 953: c->sock = -1;
954: c->type = SSH_CHANNEL_CLOSED;
955: packet_start(SSH_MSG_CHANNEL_CLOSE);
956: packet_put_int(c->remote_id);
957: packet_send();
958: }
959: }
1.25 markus 960:
1.127 itojun 961: static void
1.237 deraadt 962: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 963: {
1.121 markus 964: int ret = x11_open_helper(&c->output);
1.133 markus 965:
966: /* c->force_drain = 1; */
967:
1.41 markus 968: if (ret == 1) {
969: c->type = SSH_CHANNEL_OPEN;
1.157 markus 970: channel_pre_open(c, readset, writeset);
1.41 markus 971: } else if (ret == -1) {
1.188 itojun 972: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 973: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 974: chan_read_failed(c);
975: buffer_clear(&c->input);
976: chan_ibuf_empty(c);
977: buffer_clear(&c->output);
978: /* for proto v1, the peer will send an IEOF */
979: if (compat20)
980: chan_write_failed(c);
981: else
982: c->type = SSH_CHANNEL_OPEN;
1.194 markus 983: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 984: }
985: }
1.25 markus 986:
1.104 markus 987: /* try to decode a socks4 header */
1.259 stevesk 988: /* ARGSUSED */
1.127 itojun 989: static int
1.237 deraadt 990: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 991: {
1.181 markus 992: char *p, *host;
1.292 djm 993: u_int len, have, i, found, need;
1.148 deraadt 994: char username[256];
1.103 markus 995: struct {
996: u_int8_t version;
997: u_int8_t command;
998: u_int16_t dest_port;
1.104 markus 999: struct in_addr dest_addr;
1.103 markus 1000: } s4_req, s4_rsp;
1001:
1.104 markus 1002: debug2("channel %d: decode socks4", c->self);
1.109 markus 1003:
1004: have = buffer_len(&c->input);
1005: len = sizeof(s4_req);
1006: if (have < len)
1007: return 0;
1008: p = buffer_ptr(&c->input);
1.292 djm 1009:
1010: need = 1;
1011: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1012: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1013: debug2("channel %d: socks4a request", c->self);
1014: /* ... and needs an extra string (the hostname) */
1015: need = 2;
1016: }
1017: /* Check for terminating NUL on the string(s) */
1.109 markus 1018: for (found = 0, i = len; i < have; i++) {
1019: if (p[i] == '\0') {
1.292 djm 1020: found++;
1021: if (found == need)
1022: break;
1.109 markus 1023: }
1024: if (i > 1024) {
1025: /* the peer is probably sending garbage */
1026: debug("channel %d: decode socks4: too long",
1027: c->self);
1028: return -1;
1029: }
1030: }
1.292 djm 1031: if (found < need)
1.109 markus 1032: return 0;
1.103 markus 1033: buffer_get(&c->input, (char *)&s4_req.version, 1);
1034: buffer_get(&c->input, (char *)&s4_req.command, 1);
1035: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1036: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1037: have = buffer_len(&c->input);
1.103 markus 1038: p = buffer_ptr(&c->input);
1039: len = strlen(p);
1.106 markus 1040: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1041: len++; /* trailing '\0' */
1.103 markus 1042: if (len > have)
1.104 markus 1043: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1044: c->self, len, have);
1045: strlcpy(username, p, sizeof(username));
1046: buffer_consume(&c->input, len);
1047:
1.293 djm 1048: if (c->path != NULL) {
1049: xfree(c->path);
1050: c->path = NULL;
1051: }
1.292 djm 1052: if (need == 1) { /* SOCKS4: one string */
1053: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1054: c->path = xstrdup(host);
1.292 djm 1055: } else { /* SOCKS4A: two strings */
1056: have = buffer_len(&c->input);
1057: p = buffer_ptr(&c->input);
1058: len = strlen(p);
1059: debug2("channel %d: decode socks4a: host %s/%d",
1060: c->self, p, len);
1061: len++; /* trailing '\0' */
1062: if (len > have)
1063: fatal("channel %d: decode socks4a: len %d > have %d",
1064: c->self, len, have);
1.293 djm 1065: if (len > NI_MAXHOST) {
1.292 djm 1066: error("channel %d: hostname \"%.100s\" too long",
1067: c->self, p);
1068: return -1;
1069: }
1.293 djm 1070: c->path = xstrdup(p);
1.292 djm 1071: buffer_consume(&c->input, len);
1072: }
1.103 markus 1073: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1074:
1.194 markus 1075: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1076: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1077:
1.104 markus 1078: if (s4_req.command != 1) {
1.292 djm 1079: debug("channel %d: cannot handle: %s cn %d",
1080: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1081: return -1;
1.103 markus 1082: }
1.104 markus 1083: s4_rsp.version = 0; /* vn: 0 for reply */
1084: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1085: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1086: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1087: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1088: return 1;
1089: }
1090:
1.193 markus 1091: /* try to decode a socks5 header */
1092: #define SSH_SOCKS5_AUTHDONE 0x1000
1093: #define SSH_SOCKS5_NOAUTH 0x00
1094: #define SSH_SOCKS5_IPV4 0x01
1095: #define SSH_SOCKS5_DOMAIN 0x03
1096: #define SSH_SOCKS5_IPV6 0x04
1097: #define SSH_SOCKS5_CONNECT 0x01
1098: #define SSH_SOCKS5_SUCCESS 0x00
1099:
1.259 stevesk 1100: /* ARGSUSED */
1.193 markus 1101: static int
1.237 deraadt 1102: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1103: {
1104: struct {
1105: u_int8_t version;
1106: u_int8_t command;
1107: u_int8_t reserved;
1108: u_int8_t atyp;
1109: } s5_req, s5_rsp;
1110: u_int16_t dest_port;
1.293 djm 1111: u_char *p, dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.252 djm 1112: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1113:
1114: debug2("channel %d: decode socks5", c->self);
1115: p = buffer_ptr(&c->input);
1116: if (p[0] != 0x05)
1117: return -1;
1118: have = buffer_len(&c->input);
1119: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1120: /* format: ver | nmethods | methods */
1.198 djm 1121: if (have < 2)
1.193 markus 1122: return 0;
1123: nmethods = p[1];
1124: if (have < nmethods + 2)
1125: return 0;
1126: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1127: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1128: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1129: found = 1;
1130: break;
1131: }
1132: }
1133: if (!found) {
1134: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1135: c->self);
1136: return -1;
1137: }
1138: buffer_consume(&c->input, nmethods + 2);
1139: buffer_put_char(&c->output, 0x05); /* version */
1140: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1141: FD_SET(c->sock, writeset);
1142: c->flags |= SSH_SOCKS5_AUTHDONE;
1143: debug2("channel %d: socks5 auth done", c->self);
1144: return 0; /* need more */
1145: }
1146: debug2("channel %d: socks5 post auth", c->self);
1147: if (have < sizeof(s5_req)+1)
1148: return 0; /* need more */
1.247 deraadt 1149: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1150: if (s5_req.version != 0x05 ||
1151: s5_req.command != SSH_SOCKS5_CONNECT ||
1152: s5_req.reserved != 0x00) {
1.194 markus 1153: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1154: return -1;
1155: }
1.213 deraadt 1156: switch (s5_req.atyp){
1.193 markus 1157: case SSH_SOCKS5_IPV4:
1158: addrlen = 4;
1159: af = AF_INET;
1160: break;
1161: case SSH_SOCKS5_DOMAIN:
1162: addrlen = p[sizeof(s5_req)];
1163: af = -1;
1164: break;
1165: case SSH_SOCKS5_IPV6:
1166: addrlen = 16;
1167: af = AF_INET6;
1168: break;
1169: default:
1.194 markus 1170: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1171: return -1;
1172: }
1.252 djm 1173: need = sizeof(s5_req) + addrlen + 2;
1174: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1175: need++;
1176: if (have < need)
1.193 markus 1177: return 0;
1178: buffer_consume(&c->input, sizeof(s5_req));
1179: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1180: buffer_consume(&c->input, 1); /* host string length */
1181: buffer_get(&c->input, (char *)&dest_addr, addrlen);
1182: buffer_get(&c->input, (char *)&dest_port, 2);
1183: dest_addr[addrlen] = '\0';
1.293 djm 1184: if (c->path != NULL) {
1185: xfree(c->path);
1186: c->path = NULL;
1187: }
1188: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1189: if (addrlen >= NI_MAXHOST) {
1.293 djm 1190: error("channel %d: dynamic request: socks5 hostname "
1191: "\"%.100s\" too long", c->self, dest_addr);
1192: return -1;
1193: }
1194: c->path = xstrdup(dest_addr);
1195: } else {
1196: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1197: return -1;
1198: c->path = xstrdup(ntop);
1199: }
1.193 markus 1200: c->host_port = ntohs(dest_port);
1.198 djm 1201:
1.194 markus 1202: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1203: c->self, c->path, c->host_port, s5_req.command);
1204:
1205: s5_rsp.version = 0x05;
1206: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1207: s5_rsp.reserved = 0; /* ignored */
1208: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1209: ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1210: dest_port = 0; /* ignored */
1211:
1.246 deraadt 1212: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1213: buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1214: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1215: return 1;
1216: }
1217:
1.104 markus 1218: /* dynamic port forwarding */
1.127 itojun 1219: static void
1.237 deraadt 1220: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1221: {
1222: u_char *p;
1.217 djm 1223: u_int have;
1224: int ret;
1.103 markus 1225:
1.104 markus 1226: have = buffer_len(&c->input);
1227: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1228: /* buffer_dump(&c->input); */
1.104 markus 1229: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1230: if (have < 3) {
1.104 markus 1231: /* need more */
1232: FD_SET(c->sock, readset);
1233: return;
1234: }
1235: /* try to guess the protocol */
1236: p = buffer_ptr(&c->input);
1237: switch (p[0]) {
1238: case 0x04:
1239: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1240: break;
1241: case 0x05:
1242: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1243: break;
1244: default:
1245: ret = -1;
1246: break;
1247: }
1248: if (ret < 0) {
1.113 markus 1249: chan_mark_dead(c);
1.104 markus 1250: } else if (ret == 0) {
1251: debug2("channel %d: pre_dynamic: need more", c->self);
1252: /* need more */
1253: FD_SET(c->sock, readset);
1254: } else {
1255: /* switch to the next state */
1256: c->type = SSH_CHANNEL_OPENING;
1257: port_open_helper(c, "direct-tcpip");
1258: }
1.103 markus 1259: }
1260:
1.41 markus 1261: /* This is our fake X11 server socket. */
1.259 stevesk 1262: /* ARGSUSED */
1.127 itojun 1263: static void
1.237 deraadt 1264: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1265: {
1.113 markus 1266: Channel *nc;
1.285 djm 1267: struct sockaddr_storage addr;
1.162 stevesk 1268: int newsock;
1.41 markus 1269: socklen_t addrlen;
1.85 markus 1270: char buf[16384], *remote_ipaddr;
1.51 markus 1271: int remote_port;
1.25 markus 1272:
1.41 markus 1273: if (FD_ISSET(c->sock, readset)) {
1274: debug("X11 connection requested.");
1275: addrlen = sizeof(addr);
1.285 djm 1276: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1277: if (c->single_connection) {
1.194 markus 1278: debug2("single_connection: closing X11 listener.");
1.149 markus 1279: channel_close_fd(&c->sock);
1280: chan_mark_dead(c);
1281: }
1.41 markus 1282: if (newsock < 0) {
1283: error("accept: %.100s", strerror(errno));
1284: return;
1285: }
1.162 stevesk 1286: set_nodelay(newsock);
1.85 markus 1287: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1288: remote_port = get_peer_port(newsock);
1.41 markus 1289: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1290: remote_ipaddr, remote_port);
1.51 markus 1291:
1.113 markus 1292: nc = channel_new("accepted x11 socket",
1.51 markus 1293: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1294: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1295: if (compat20) {
1296: packet_start(SSH2_MSG_CHANNEL_OPEN);
1297: packet_put_cstring("x11");
1.113 markus 1298: packet_put_int(nc->self);
1.149 markus 1299: packet_put_int(nc->local_window_max);
1300: packet_put_int(nc->local_maxpacket);
1.85 markus 1301: /* originator ipaddr and port */
1302: packet_put_cstring(remote_ipaddr);
1.57 markus 1303: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1304: debug2("ssh2 x11 bug compat mode");
1.57 markus 1305: } else {
1306: packet_put_int(remote_port);
1307: }
1.51 markus 1308: packet_send();
1309: } else {
1310: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1311: packet_put_int(nc->self);
1.121 markus 1312: if (packet_get_protocol_flags() &
1313: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1314: packet_put_cstring(buf);
1.51 markus 1315: packet_send();
1316: }
1.85 markus 1317: xfree(remote_ipaddr);
1.41 markus 1318: }
1319: }
1.25 markus 1320:
1.127 itojun 1321: static void
1.103 markus 1322: port_open_helper(Channel *c, char *rtype)
1323: {
1324: int direct;
1325: char buf[1024];
1326: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1327: int remote_port = get_peer_port(c->sock);
1.103 markus 1328:
1329: direct = (strcmp(rtype, "direct-tcpip") == 0);
1330:
1331: snprintf(buf, sizeof buf,
1332: "%s: listening port %d for %.100s port %d, "
1333: "connect from %.200s port %d",
1334: rtype, c->listening_port, c->path, c->host_port,
1335: remote_ipaddr, remote_port);
1336:
1337: xfree(c->remote_name);
1338: c->remote_name = xstrdup(buf);
1339:
1340: if (compat20) {
1341: packet_start(SSH2_MSG_CHANNEL_OPEN);
1342: packet_put_cstring(rtype);
1343: packet_put_int(c->self);
1344: packet_put_int(c->local_window_max);
1345: packet_put_int(c->local_maxpacket);
1346: if (direct) {
1347: /* target host, port */
1348: packet_put_cstring(c->path);
1349: packet_put_int(c->host_port);
1350: } else {
1351: /* listen address, port */
1352: packet_put_cstring(c->path);
1353: packet_put_int(c->listening_port);
1354: }
1355: /* originator host and port */
1356: packet_put_cstring(remote_ipaddr);
1.216 markus 1357: packet_put_int((u_int)remote_port);
1.103 markus 1358: packet_send();
1359: } else {
1360: packet_start(SSH_MSG_PORT_OPEN);
1361: packet_put_int(c->self);
1362: packet_put_cstring(c->path);
1363: packet_put_int(c->host_port);
1.121 markus 1364: if (packet_get_protocol_flags() &
1365: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1366: packet_put_cstring(c->remote_name);
1367: packet_send();
1368: }
1369: xfree(remote_ipaddr);
1370: }
1371:
1.226 djm 1372: static void
1373: channel_set_reuseaddr(int fd)
1374: {
1375: int on = 1;
1376:
1377: /*
1378: * Set socket options.
1379: * Allow local port reuse in TIME_WAIT.
1380: */
1381: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1382: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1383: }
1384:
1.41 markus 1385: /*
1386: * This socket is listening for connections to a forwarded TCP/IP port.
1387: */
1.259 stevesk 1388: /* ARGSUSED */
1.127 itojun 1389: static void
1.237 deraadt 1390: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1391: {
1.103 markus 1392: Channel *nc;
1.285 djm 1393: struct sockaddr_storage addr;
1.113 markus 1394: int newsock, nextstate;
1.41 markus 1395: socklen_t addrlen;
1.103 markus 1396: char *rtype;
1.73 markus 1397:
1.41 markus 1398: if (FD_ISSET(c->sock, readset)) {
1399: debug("Connection to port %d forwarding "
1400: "to %.100s port %d requested.",
1401: c->listening_port, c->path, c->host_port);
1.103 markus 1402:
1.137 markus 1403: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1404: nextstate = SSH_CHANNEL_OPENING;
1405: rtype = "forwarded-tcpip";
1406: } else {
1407: if (c->host_port == 0) {
1408: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1409: rtype = "dynamic-tcpip";
1.137 markus 1410: } else {
1411: nextstate = SSH_CHANNEL_OPENING;
1412: rtype = "direct-tcpip";
1413: }
1414: }
1.103 markus 1415:
1.41 markus 1416: addrlen = sizeof(addr);
1.285 djm 1417: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1418: if (newsock < 0) {
1419: error("accept: %.100s", strerror(errno));
1420: return;
1421: }
1.169 stevesk 1422: set_nodelay(newsock);
1.190 markus 1423: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1424: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1425: nc->listening_port = c->listening_port;
1426: nc->host_port = c->host_port;
1.293 djm 1427: if (c->path != NULL)
1428: nc->path = xstrdup(c->path);
1.103 markus 1429:
1.299 ! markus 1430: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1431: port_open_helper(nc, rtype);
1.41 markus 1432: }
1433: }
1.25 markus 1434:
1.41 markus 1435: /*
1436: * This is the authentication agent socket listening for connections from
1437: * clients.
1438: */
1.259 stevesk 1439: /* ARGSUSED */
1.127 itojun 1440: static void
1.237 deraadt 1441: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1442: {
1.113 markus 1443: Channel *nc;
1444: int newsock;
1.285 djm 1445: struct sockaddr_storage addr;
1.41 markus 1446: socklen_t addrlen;
1.25 markus 1447:
1.41 markus 1448: if (FD_ISSET(c->sock, readset)) {
1449: addrlen = sizeof(addr);
1.285 djm 1450: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1451: if (newsock < 0) {
1452: error("accept from auth socket: %.100s", strerror(errno));
1453: return;
1454: }
1.113 markus 1455: nc = channel_new("accepted auth socket",
1.73 markus 1456: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1457: c->local_window_max, c->local_maxpacket,
1.190 markus 1458: 0, "accepted auth socket", 1);
1.73 markus 1459: if (compat20) {
1460: packet_start(SSH2_MSG_CHANNEL_OPEN);
1461: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1462: packet_put_int(nc->self);
1.73 markus 1463: packet_put_int(c->local_window_max);
1464: packet_put_int(c->local_maxpacket);
1465: } else {
1466: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1467: packet_put_int(nc->self);
1.73 markus 1468: }
1.41 markus 1469: packet_send();
1470: }
1471: }
1.25 markus 1472:
1.259 stevesk 1473: /* ARGSUSED */
1.127 itojun 1474: static void
1.237 deraadt 1475: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1476: {
1.276 djm 1477: int err = 0, sock;
1.129 stevesk 1478: socklen_t sz = sizeof(err);
1.114 markus 1479:
1.75 markus 1480: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1481: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1482: err = errno;
1483: error("getsockopt SO_ERROR failed");
1484: }
1485: if (err == 0) {
1.276 djm 1486: debug("channel %d: connected to %s port %d",
1487: c->self, c->connect_ctx.host, c->connect_ctx.port);
1488: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1489: c->type = SSH_CHANNEL_OPEN;
1490: if (compat20) {
1491: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1492: packet_put_int(c->remote_id);
1493: packet_put_int(c->self);
1494: packet_put_int(c->local_window);
1495: packet_put_int(c->local_maxpacket);
1496: } else {
1497: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1498: packet_put_int(c->remote_id);
1499: packet_put_int(c->self);
1500: }
1.75 markus 1501: } else {
1.276 djm 1502: debug("channel %d: connection failed: %s",
1.114 markus 1503: c->self, strerror(err));
1.276 djm 1504: /* Try next address, if any */
1505: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1506: close(c->sock);
1507: c->sock = c->rfd = c->wfd = sock;
1508: channel_max_fd = channel_find_maxfd();
1509: return;
1510: }
1511: /* Exhausted all addresses */
1512: error("connect_to %.100s port %d: failed.",
1513: c->connect_ctx.host, c->connect_ctx.port);
1514: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1515: if (compat20) {
1516: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1517: packet_put_int(c->remote_id);
1518: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1519: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1520: packet_put_cstring(strerror(err));
1521: packet_put_cstring("");
1522: }
1.75 markus 1523: } else {
1.114 markus 1524: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1525: packet_put_int(c->remote_id);
1.75 markus 1526: }
1.114 markus 1527: chan_mark_dead(c);
1.75 markus 1528: }
1.114 markus 1529: packet_send();
1.75 markus 1530: }
1531: }
1532:
1.259 stevesk 1533: /* ARGSUSED */
1.127 itojun 1534: static int
1.237 deraadt 1535: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1536: {
1.214 markus 1537: char buf[CHAN_RBUF];
1.41 markus 1538: int len;
1.25 markus 1539:
1.118 markus 1540: if (c->rfd != -1 &&
1.41 markus 1541: FD_ISSET(c->rfd, readset)) {
1542: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1543: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1544: return 1;
1.41 markus 1545: if (len <= 0) {
1.194 markus 1546: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1547: c->self, c->rfd, len);
1.104 markus 1548: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1549: debug2("channel %d: not open", c->self);
1.113 markus 1550: chan_mark_dead(c);
1.103 markus 1551: return -1;
1.104 markus 1552: } else if (compat13) {
1.158 markus 1553: buffer_clear(&c->output);
1.41 markus 1554: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1555: debug2("channel %d: input draining.", c->self);
1.25 markus 1556: } else {
1.41 markus 1557: chan_read_failed(c);
1.25 markus 1558: }
1.41 markus 1559: return -1;
1560: }
1.143 deraadt 1561: if (c->input_filter != NULL) {
1.66 markus 1562: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1563: debug2("channel %d: filter stops", c->self);
1.65 markus 1564: chan_read_failed(c);
1565: }
1.228 reyk 1566: } else if (c->datagram) {
1567: buffer_put_string(&c->input, buf, len);
1.65 markus 1568: } else {
1569: buffer_append(&c->input, buf, len);
1570: }
1.41 markus 1571: }
1572: return 1;
1573: }
1.241 deraadt 1574:
1.259 stevesk 1575: /* ARGSUSED */
1.127 itojun 1576: static int
1.237 deraadt 1577: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1578: {
1.95 markus 1579: struct termios tio;
1.231 reyk 1580: u_char *data = NULL, *buf;
1.134 markus 1581: u_int dlen;
1.41 markus 1582: int len;
1.25 markus 1583:
1.41 markus 1584: /* Send buffered output data to the socket. */
1.118 markus 1585: if (c->wfd != -1 &&
1.41 markus 1586: FD_ISSET(c->wfd, writeset) &&
1587: buffer_len(&c->output) > 0) {
1.231 reyk 1588: if (c->output_filter != NULL) {
1589: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1590: debug2("channel %d: filter stops", c->self);
1.232 reyk 1591: if (c->type != SSH_CHANNEL_OPEN)
1592: chan_mark_dead(c);
1593: else
1594: chan_write_failed(c);
1595: return -1;
1.231 reyk 1596: }
1597: } else if (c->datagram) {
1598: buf = data = buffer_get_string(&c->output, &dlen);
1599: } else {
1600: buf = data = buffer_ptr(&c->output);
1601: dlen = buffer_len(&c->output);
1602: }
1603:
1.228 reyk 1604: if (c->datagram) {
1605: /* ignore truncated writes, datagrams might get lost */
1606: c->local_consumed += dlen + 4;
1.231 reyk 1607: len = write(c->wfd, buf, dlen);
1.228 reyk 1608: xfree(data);
1609: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1610: return 1;
1611: if (len <= 0) {
1612: if (c->type != SSH_CHANNEL_OPEN)
1613: chan_mark_dead(c);
1614: else
1615: chan_write_failed(c);
1616: return -1;
1617: }
1618: return 1;
1619: }
1.231 reyk 1620:
1621: len = write(c->wfd, buf, dlen);
1.53 markus 1622: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1623: return 1;
1.41 markus 1624: if (len <= 0) {
1.104 markus 1625: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1626: debug2("channel %d: not open", c->self);
1.113 markus 1627: chan_mark_dead(c);
1.104 markus 1628: return -1;
1629: } else if (compat13) {
1.158 markus 1630: buffer_clear(&c->output);
1.194 markus 1631: debug2("channel %d: input draining.", c->self);
1.41 markus 1632: c->type = SSH_CHANNEL_INPUT_DRAINING;
1633: } else {
1634: chan_write_failed(c);
1635: }
1636: return -1;
1.91 markus 1637: }
1.231 reyk 1638: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1639: if (tcgetattr(c->wfd, &tio) == 0 &&
1640: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1641: /*
1642: * Simulate echo to reduce the impact of
1.96 markus 1643: * traffic analysis. We need to match the
1.95 markus 1644: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1645: * (4 byte channel id + buf)
1.91 markus 1646: */
1.95 markus 1647: packet_send_ignore(4 + len);
1.91 markus 1648: packet_send();
1649: }
1.25 markus 1650: }
1.41 markus 1651: buffer_consume(&c->output, len);
1.44 markus 1652: if (compat20 && len > 0) {
1653: c->local_consumed += len;
1654: }
1655: }
1656: return 1;
1657: }
1.241 deraadt 1658:
1.127 itojun 1659: static int
1.237 deraadt 1660: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1661: {
1.214 markus 1662: char buf[CHAN_RBUF];
1.44 markus 1663: int len;
1664:
1.45 markus 1665: /** XXX handle drain efd, too */
1.44 markus 1666: if (c->efd != -1) {
1667: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1668: FD_ISSET(c->efd, writeset) &&
1669: buffer_len(&c->extended) > 0) {
1670: len = write(c->efd, buffer_ptr(&c->extended),
1671: buffer_len(&c->extended));
1.70 markus 1672: debug2("channel %d: written %d to efd %d",
1.44 markus 1673: c->self, len, c->efd);
1.93 markus 1674: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1675: return 1;
1676: if (len <= 0) {
1677: debug2("channel %d: closing write-efd %d",
1678: c->self, c->efd);
1.132 markus 1679: channel_close_fd(&c->efd);
1.93 markus 1680: } else {
1.44 markus 1681: buffer_consume(&c->extended, len);
1682: c->local_consumed += len;
1683: }
1684: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1685: FD_ISSET(c->efd, readset)) {
1686: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1687: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1688: c->self, len, c->efd);
1.93 markus 1689: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1690: return 1;
1691: if (len <= 0) {
1692: debug2("channel %d: closing read-efd %d",
1.45 markus 1693: c->self, c->efd);
1.132 markus 1694: channel_close_fd(&c->efd);
1.93 markus 1695: } else {
1.44 markus 1696: buffer_append(&c->extended, buf, len);
1.93 markus 1697: }
1.44 markus 1698: }
1699: }
1700: return 1;
1701: }
1.241 deraadt 1702:
1.259 stevesk 1703: /* ARGSUSED */
1.127 itojun 1704: static int
1.237 deraadt 1705: channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
1.204 djm 1706: {
1707: char buf[16];
1708: int len;
1709:
1710: /* Monitor control fd to detect if the slave client exits */
1711: if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1712: len = read(c->ctl_fd, buf, sizeof(buf));
1713: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1714: return 1;
1715: if (len <= 0) {
1716: debug2("channel %d: ctl read<=0", c->self);
1717: if (c->type != SSH_CHANNEL_OPEN) {
1718: debug2("channel %d: not open", c->self);
1719: chan_mark_dead(c);
1720: return -1;
1721: } else {
1722: chan_read_failed(c);
1723: chan_write_failed(c);
1724: }
1725: return -1;
1726: } else
1727: fatal("%s: unexpected data on ctl fd", __func__);
1728: }
1729: return 1;
1730: }
1.241 deraadt 1731:
1.204 djm 1732: static int
1.93 markus 1733: channel_check_window(Channel *c)
1.44 markus 1734: {
1.104 markus 1735: if (c->type == SSH_CHANNEL_OPEN &&
1736: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1737: ((c->local_window_max - c->local_window >
1.269 markus 1738: c->local_maxpacket*3) ||
1739: c->local_window < c->local_window_max/2) &&
1.44 markus 1740: c->local_consumed > 0) {
1741: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1742: packet_put_int(c->remote_id);
1743: packet_put_int(c->local_consumed);
1744: packet_send();
1.70 markus 1745: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1746: c->self, c->local_window,
1747: c->local_consumed);
1748: c->local_window += c->local_consumed;
1749: c->local_consumed = 0;
1.1 deraadt 1750: }
1.41 markus 1751: return 1;
1.1 deraadt 1752: }
1753:
1.127 itojun 1754: static void
1.237 deraadt 1755: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1756: {
1757: channel_handle_rfd(c, readset, writeset);
1758: channel_handle_wfd(c, readset, writeset);
1.157 markus 1759: if (!compat20)
1.137 markus 1760: return;
1.44 markus 1761: channel_handle_efd(c, readset, writeset);
1.204 djm 1762: channel_handle_ctl(c, readset, writeset);
1.93 markus 1763: channel_check_window(c);
1.44 markus 1764: }
1765:
1.259 stevesk 1766: /* ARGSUSED */
1.127 itojun 1767: static void
1.237 deraadt 1768: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1769: {
1.41 markus 1770: int len;
1.180 deraadt 1771:
1.41 markus 1772: /* Send buffered output data to the socket. */
1773: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1774: len = write(c->sock, buffer_ptr(&c->output),
1775: buffer_len(&c->output));
1776: if (len <= 0)
1.158 markus 1777: buffer_clear(&c->output);
1.41 markus 1778: else
1779: buffer_consume(&c->output, len);
1780: }
1781: }
1.25 markus 1782:
1.127 itojun 1783: static void
1.44 markus 1784: channel_handler_init_20(void)
1785: {
1.157 markus 1786: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1787: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1788: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1789: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1790: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1791: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1792: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1793: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1794:
1.157 markus 1795: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1796: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1797: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1798: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1799: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1800: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1801: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1802: }
1803:
1.127 itojun 1804: static void
1.41 markus 1805: channel_handler_init_13(void)
1806: {
1807: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1808: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1809: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1810: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1811: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1812: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1813: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1814: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1815: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1816:
1.157 markus 1817: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1818: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1819: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1820: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1821: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1822: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1823: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1824: }
1.25 markus 1825:
1.127 itojun 1826: static void
1.41 markus 1827: channel_handler_init_15(void)
1828: {
1.157 markus 1829: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1830: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1831: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1832: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1833: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1834: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1835: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1836:
1.41 markus 1837: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1838: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1839: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1840: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1841: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1842: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1843: }
1.27 markus 1844:
1.127 itojun 1845: static void
1.41 markus 1846: channel_handler_init(void)
1847: {
1848: int i;
1.180 deraadt 1849:
1.148 deraadt 1850: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1851: channel_pre[i] = NULL;
1852: channel_post[i] = NULL;
1853: }
1.44 markus 1854: if (compat20)
1855: channel_handler_init_20();
1856: else if (compat13)
1.41 markus 1857: channel_handler_init_13();
1858: else
1859: channel_handler_init_15();
1860: }
1.25 markus 1861:
1.140 markus 1862: /* gc dead channels */
1863: static void
1864: channel_garbage_collect(Channel *c)
1865: {
1866: if (c == NULL)
1867: return;
1868: if (c->detach_user != NULL) {
1.225 djm 1869: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1870: return;
1.194 markus 1871: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1872: c->detach_user(c->self, NULL);
1873: /* if we still have a callback */
1874: if (c->detach_user != NULL)
1875: return;
1.194 markus 1876: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1877: }
1878: if (!chan_is_dead(c, 1))
1879: return;
1.194 markus 1880: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1881: channel_free(c);
1882: }
1883:
1.127 itojun 1884: static void
1.237 deraadt 1885: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
1.41 markus 1886: {
1887: static int did_init = 0;
1.299 ! markus 1888: u_int i, oalloc;
1.41 markus 1889: Channel *c;
1.25 markus 1890:
1.41 markus 1891: if (!did_init) {
1892: channel_handler_init();
1893: did_init = 1;
1894: }
1.299 ! markus 1895: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 1896: c = channels[i];
1897: if (c == NULL)
1.41 markus 1898: continue;
1.299 ! markus 1899: if (c->delayed) {
! 1900: if (ftab == channel_pre)
! 1901: c->delayed = 0;
! 1902: else
! 1903: continue;
! 1904: }
1.118 markus 1905: if (ftab[c->type] != NULL)
1906: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1907: channel_garbage_collect(c);
1.1 deraadt 1908: }
1909: }
1910:
1.121 markus 1911: /*
1912: * Allocate/update select bitmasks and add any bits relevant to channels in
1913: * select bitmasks.
1914: */
1.49 markus 1915: void
1.100 markus 1916: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.209 avsm 1917: u_int *nallocp, int rekeying)
1.41 markus 1918: {
1.243 djm 1919: u_int n, sz, nfdset;
1.84 markus 1920:
1921: n = MAX(*maxfdp, channel_max_fd);
1922:
1.243 djm 1923: nfdset = howmany(n+1, NFDBITS);
1924: /* Explicitly test here, because xrealloc isn't always called */
1925: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1926: fatal("channel_prepare_select: max_fd (%d) is too large", n);
1927: sz = nfdset * sizeof(fd_mask);
1928:
1.132 markus 1929: /* perhaps check sz < nalloc/2 and shrink? */
1930: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 1931: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1932: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 1933: *nallocp = sz;
1.84 markus 1934: }
1.132 markus 1935: *maxfdp = n;
1.84 markus 1936: memset(*readsetp, 0, sz);
1937: memset(*writesetp, 0, sz);
1938:
1.100 markus 1939: if (!rekeying)
1940: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1941: }
1942:
1.121 markus 1943: /*
1944: * After select, perform any appropriate operations for channels which have
1945: * events pending.
1946: */
1.49 markus 1947: void
1.237 deraadt 1948: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 1949: {
1950: channel_handler(channel_post, readset, writeset);
1951: }
1952:
1.121 markus 1953:
1.84 markus 1954: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 1955: void
1.142 itojun 1956: channel_output_poll(void)
1.1 deraadt 1957: {
1.41 markus 1958: Channel *c;
1.209 avsm 1959: u_int i, len;
1.1 deraadt 1960:
1.25 markus 1961: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1962: c = channels[i];
1963: if (c == NULL)
1964: continue;
1.37 markus 1965:
1.121 markus 1966: /*
1967: * We are only interested in channels that can have buffered
1968: * incoming data.
1969: */
1.37 markus 1970: if (compat13) {
1.41 markus 1971: if (c->type != SSH_CHANNEL_OPEN &&
1972: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1973: continue;
1974: } else {
1.41 markus 1975: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1976: continue;
1977: }
1.46 markus 1978: if (compat20 &&
1979: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1980: /* XXX is this true? */
1.140 markus 1981: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1982: continue;
1983: }
1.25 markus 1984:
1985: /* Get the amount of buffered data for this channel. */
1.93 markus 1986: if ((c->istate == CHAN_INPUT_OPEN ||
1987: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1988: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 1989: if (c->datagram) {
1990: if (len > 0) {
1991: u_char *data;
1992: u_int dlen;
1993:
1994: data = buffer_get_string(&c->input,
1995: &dlen);
1996: packet_start(SSH2_MSG_CHANNEL_DATA);
1997: packet_put_int(c->remote_id);
1998: packet_put_string(data, dlen);
1999: packet_send();
2000: c->remote_window -= dlen + 4;
2001: xfree(data);
2002: }
2003: continue;
2004: }
1.121 markus 2005: /*
2006: * Send some data for the other side over the secure
2007: * connection.
2008: */
1.44 markus 2009: if (compat20) {
2010: if (len > c->remote_window)
2011: len = c->remote_window;
2012: if (len > c->remote_maxpacket)
2013: len = c->remote_maxpacket;
1.25 markus 2014: } else {
1.44 markus 2015: if (packet_is_interactive()) {
2016: if (len > 1024)
2017: len = 512;
2018: } else {
2019: /* Keep the packets at reasonable size. */
2020: if (len > packet_get_maxsize()/2)
2021: len = packet_get_maxsize()/2;
2022: }
1.25 markus 2023: }
1.41 markus 2024: if (len > 0) {
1.44 markus 2025: packet_start(compat20 ?
2026: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2027: packet_put_int(c->remote_id);
2028: packet_put_string(buffer_ptr(&c->input), len);
2029: packet_send();
2030: buffer_consume(&c->input, len);
2031: c->remote_window -= len;
2032: }
2033: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2034: if (compat13)
2035: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2036: /*
2037: * input-buffer is empty and read-socket shutdown:
1.172 markus 2038: * tell peer, that we will not send more data: send IEOF.
2039: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2040: */
1.172 markus 2041: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2042: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2043: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2044: else
2045: chan_ibuf_empty(c);
1.25 markus 2046: }
1.44 markus 2047: /* Send extended data, i.e. stderr */
2048: if (compat20 &&
1.172 markus 2049: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2050: c->remote_window > 0 &&
2051: (len = buffer_len(&c->extended)) > 0 &&
2052: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2053: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2054: c->self, c->remote_window, buffer_len(&c->extended),
2055: c->extended_usage);
1.44 markus 2056: if (len > c->remote_window)
2057: len = c->remote_window;
2058: if (len > c->remote_maxpacket)
2059: len = c->remote_maxpacket;
2060: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2061: packet_put_int(c->remote_id);
2062: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2063: packet_put_string(buffer_ptr(&c->extended), len);
2064: packet_send();
2065: buffer_consume(&c->extended, len);
2066: c->remote_window -= len;
1.93 markus 2067: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2068: }
1.25 markus 2069: }
1.1 deraadt 2070: }
2071:
1.121 markus 2072:
2073: /* -- protocol input */
1.249 djm 2074:
2075: /* ARGSUSED */
1.49 markus 2076: void
1.154 markus 2077: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2078: {
1.37 markus 2079: int id;
1.25 markus 2080: char *data;
1.77 markus 2081: u_int data_len;
1.41 markus 2082: Channel *c;
1.25 markus 2083:
2084: /* Get the channel number and verify it. */
1.37 markus 2085: id = packet_get_int();
1.41 markus 2086: c = channel_lookup(id);
2087: if (c == NULL)
1.37 markus 2088: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2089:
2090: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2091: if (c->type != SSH_CHANNEL_OPEN &&
2092: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 2093: return;
2094:
1.25 markus 2095: /* Get the data. */
1.274 markus 2096: data = packet_get_string_ptr(&data_len);
1.200 markus 2097:
2098: /*
2099: * Ignore data for protocol > 1.3 if output end is no longer open.
2100: * For protocol 2 the sending side is reducing its window as it sends
2101: * data, so we must 'fake' consumption of the data in order to ensure
2102: * that window updates are sent back. Otherwise the connection might
2103: * deadlock.
2104: */
2105: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2106: if (compat20) {
2107: c->local_window -= data_len;
2108: c->local_consumed += data_len;
2109: }
2110: return;
2111: }
1.41 markus 2112:
1.143 deraadt 2113: if (compat20) {
1.44 markus 2114: if (data_len > c->local_maxpacket) {
1.188 itojun 2115: logit("channel %d: rcvd big packet %d, maxpack %d",
1.44 markus 2116: c->self, data_len, c->local_maxpacket);
2117: }
2118: if (data_len > c->local_window) {
1.188 itojun 2119: logit("channel %d: rcvd too much data %d, win %d",
1.44 markus 2120: c->self, data_len, c->local_window);
2121: return;
2122: }
2123: c->local_window -= data_len;
2124: }
1.228 reyk 2125: if (c->datagram)
2126: buffer_put_string(&c->output, data, data_len);
2127: else
2128: buffer_append(&c->output, data, data_len);
1.274 markus 2129: packet_check_eom();
1.1 deraadt 2130: }
1.121 markus 2131:
1.249 djm 2132: /* ARGSUSED */
1.49 markus 2133: void
1.154 markus 2134: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2135: {
2136: int id;
2137: char *data;
1.177 markus 2138: u_int data_len, tcode;
1.44 markus 2139: Channel *c;
2140:
2141: /* Get the channel number and verify it. */
2142: id = packet_get_int();
2143: c = channel_lookup(id);
2144:
2145: if (c == NULL)
2146: packet_disconnect("Received extended_data for bad channel %d.", id);
2147: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2148: logit("channel %d: ext data for non open", id);
1.44 markus 2149: return;
1.172 markus 2150: }
2151: if (c->flags & CHAN_EOF_RCVD) {
2152: if (datafellows & SSH_BUG_EXTEOF)
2153: debug("channel %d: accepting ext data after eof", id);
2154: else
2155: packet_disconnect("Received extended_data after EOF "
2156: "on channel %d.", id);
1.44 markus 2157: }
2158: tcode = packet_get_int();
2159: if (c->efd == -1 ||
2160: c->extended_usage != CHAN_EXTENDED_WRITE ||
2161: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2162: logit("channel %d: bad ext data", c->self);
1.44 markus 2163: return;
2164: }
2165: data = packet_get_string(&data_len);
1.152 markus 2166: packet_check_eom();
1.44 markus 2167: if (data_len > c->local_window) {
1.188 itojun 2168: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2169: c->self, data_len, c->local_window);
2170: xfree(data);
2171: return;
2172: }
1.70 markus 2173: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2174: c->local_window -= data_len;
2175: buffer_append(&c->extended, data, data_len);
2176: xfree(data);
2177: }
2178:
1.249 djm 2179: /* ARGSUSED */
1.49 markus 2180: void
1.154 markus 2181: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2182: {
2183: int id;
2184: Channel *c;
2185:
2186: id = packet_get_int();
1.152 markus 2187: packet_check_eom();
1.41 markus 2188: c = channel_lookup(id);
2189: if (c == NULL)
2190: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2191: chan_rcvd_ieof(c);
1.133 markus 2192:
2193: /* XXX force input close */
1.156 markus 2194: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2195: debug("channel %d: FORCE input drain", c->self);
2196: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2197: if (buffer_len(&c->input) == 0)
2198: chan_ibuf_empty(c);
1.133 markus 2199: }
2200:
1.41 markus 2201: }
1.1 deraadt 2202:
1.249 djm 2203: /* ARGSUSED */
1.49 markus 2204: void
1.154 markus 2205: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2206: {
1.41 markus 2207: int id;
2208: Channel *c;
1.1 deraadt 2209:
1.41 markus 2210: id = packet_get_int();
1.152 markus 2211: packet_check_eom();
1.41 markus 2212: c = channel_lookup(id);
2213: if (c == NULL)
2214: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2215:
2216: /*
2217: * Send a confirmation that we have closed the channel and no more
2218: * data is coming for it.
2219: */
1.25 markus 2220: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2221: packet_put_int(c->remote_id);
1.25 markus 2222: packet_send();
2223:
1.27 markus 2224: /*
2225: * If the channel is in closed state, we have sent a close request,
2226: * and the other side will eventually respond with a confirmation.
2227: * Thus, we cannot free the channel here, because then there would be
2228: * no-one to receive the confirmation. The channel gets freed when
2229: * the confirmation arrives.
2230: */
1.41 markus 2231: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2232: /*
2233: * Not a closed channel - mark it as draining, which will
2234: * cause it to be freed later.
2235: */
1.158 markus 2236: buffer_clear(&c->input);
1.41 markus 2237: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2238: }
1.1 deraadt 2239: }
2240:
1.41 markus 2241: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2242: /* ARGSUSED */
1.49 markus 2243: void
1.154 markus 2244: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2245: {
2246: int id = packet_get_int();
2247: Channel *c = channel_lookup(id);
1.151 markus 2248:
1.152 markus 2249: packet_check_eom();
1.41 markus 2250: if (c == NULL)
2251: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2252: chan_rcvd_oclose(c);
2253: }
1.1 deraadt 2254:
1.249 djm 2255: /* ARGSUSED */
1.49 markus 2256: void
1.154 markus 2257: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2258: {
1.41 markus 2259: int id = packet_get_int();
2260: Channel *c = channel_lookup(id);
1.1 deraadt 2261:
1.152 markus 2262: packet_check_eom();
1.41 markus 2263: if (c == NULL)
2264: packet_disconnect("Received close confirmation for "
2265: "out-of-range channel %d.", id);
2266: if (c->type != SSH_CHANNEL_CLOSED)
2267: packet_disconnect("Received close confirmation for "
2268: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2269: channel_free(c);
1.1 deraadt 2270: }
2271:
1.249 djm 2272: /* ARGSUSED */
1.49 markus 2273: void
1.154 markus 2274: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2275: {
1.41 markus 2276: int id, remote_id;
2277: Channel *c;
1.1 deraadt 2278:
1.41 markus 2279: id = packet_get_int();
2280: c = channel_lookup(id);
1.25 markus 2281:
1.41 markus 2282: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2283: packet_disconnect("Received open confirmation for "
2284: "non-opening channel %d.", id);
2285: remote_id = packet_get_int();
1.27 markus 2286: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2287: c->remote_id = remote_id;
2288: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2289:
2290: if (compat20) {
2291: c->remote_window = packet_get_int();
2292: c->remote_maxpacket = packet_get_int();
1.275 djm 2293: if (c->open_confirm) {
1.70 markus 2294: debug2("callback start");
1.275 djm 2295: c->open_confirm(c->self, c->open_confirm_ctx);
1.70 markus 2296: debug2("callback done");
1.44 markus 2297: }
1.194 markus 2298: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2299: c->remote_window, c->remote_maxpacket);
2300: }
1.152 markus 2301: packet_check_eom();
1.1 deraadt 2302: }
2303:
1.127 itojun 2304: static char *
1.114 markus 2305: reason2txt(int reason)
2306: {
1.143 deraadt 2307: switch (reason) {
1.114 markus 2308: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2309: return "administratively prohibited";
2310: case SSH2_OPEN_CONNECT_FAILED:
2311: return "connect failed";
2312: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2313: return "unknown channel type";
2314: case SSH2_OPEN_RESOURCE_SHORTAGE:
2315: return "resource shortage";
2316: }
1.117 stevesk 2317: return "unknown reason";
1.114 markus 2318: }
2319:
1.249 djm 2320: /* ARGSUSED */
1.49 markus 2321: void
1.154 markus 2322: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2323: {
1.86 markus 2324: int id, reason;
2325: char *msg = NULL, *lang = NULL;
1.41 markus 2326: Channel *c;
2327:
2328: id = packet_get_int();
2329: c = channel_lookup(id);
1.25 markus 2330:
1.41 markus 2331: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2332: packet_disconnect("Received open failure for "
2333: "non-opening channel %d.", id);
1.44 markus 2334: if (compat20) {
1.86 markus 2335: reason = packet_get_int();
1.110 markus 2336: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2337: msg = packet_get_string(NULL);
2338: lang = packet_get_string(NULL);
2339: }
1.188 itojun 2340: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2341: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 2342: if (msg != NULL)
2343: xfree(msg);
2344: if (lang != NULL)
2345: xfree(lang);
1.44 markus 2346: }
1.152 markus 2347: packet_check_eom();
1.291 djm 2348: /* Schedule the channel for cleanup/deletion. */
2349: chan_mark_dead(c);
1.44 markus 2350: }
2351:
1.249 djm 2352: /* ARGSUSED */
1.121 markus 2353: void
1.154 markus 2354: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2355: {
2356: Channel *c;
1.178 markus 2357: int id;
2358: u_int adjust;
1.121 markus 2359:
2360: if (!compat20)
2361: return;
2362:
2363: /* Get the channel number and verify it. */
2364: id = packet_get_int();
2365: c = channel_lookup(id);
1.1 deraadt 2366:
1.229 markus 2367: if (c == NULL) {
2368: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2369: return;
2370: }
2371: adjust = packet_get_int();
1.152 markus 2372: packet_check_eom();
1.178 markus 2373: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2374: c->remote_window += adjust;
2375: }
1.1 deraadt 2376:
1.249 djm 2377: /* ARGSUSED */
1.121 markus 2378: void
1.154 markus 2379: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2380: {
1.121 markus 2381: Channel *c = NULL;
2382: u_short host_port;
2383: char *host, *originator_string;
1.276 djm 2384: int remote_id;
1.121 markus 2385:
2386: remote_id = packet_get_int();
2387: host = packet_get_string(NULL);
2388: host_port = packet_get_int();
1.25 markus 2389:
1.121 markus 2390: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2391: originator_string = packet_get_string(NULL);
2392: } else {
2393: originator_string = xstrdup("unknown (remote did not supply name)");
2394: }
1.152 markus 2395: packet_check_eom();
1.276 djm 2396: c = channel_connect_to(host, host_port,
2397: "connected socket", originator_string);
1.190 markus 2398: xfree(originator_string);
1.276 djm 2399: xfree(host);
1.121 markus 2400: if (c == NULL) {
2401: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2402: packet_put_int(remote_id);
2403: packet_send();
1.276 djm 2404: } else
2405: c->remote_id = remote_id;
1.1 deraadt 2406: }
2407:
1.275 djm 2408: /* ARGSUSED */
2409: void
2410: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2411: {
2412: Channel *c;
2413: struct channel_confirm *cc;
1.289 markus 2414: int id;
1.275 djm 2415:
2416: /* Reset keepalive timeout */
1.296 andreas 2417: packet_set_alive_timeouts(0);
1.275 djm 2418:
1.289 markus 2419: id = packet_get_int();
1.275 djm 2420: packet_check_eom();
2421:
1.289 markus 2422: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2423:
1.289 markus 2424: if ((c = channel_lookup(id)) == NULL) {
2425: logit("channel_input_status_confirm: %d: unknown", id);
1.275 djm 2426: return;
2427: }
2428: ;
2429: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
2430: return;
2431: cc->cb(type, c, cc->ctx);
2432: TAILQ_REMOVE(&c->status_confirms, cc, entry);
2433: bzero(cc, sizeof(*cc));
2434: xfree(cc);
2435: }
1.121 markus 2436:
2437: /* -- tcp forwarding */
1.135 markus 2438:
2439: void
2440: channel_set_af(int af)
2441: {
2442: IPv4or6 = af;
2443: }
1.121 markus 2444:
1.297 reyk 2445: void
2446: channel_set_rdomain(int rdomain)
2447: {
2448: channel_rdomain = rdomain;
2449: }
2450:
1.160 markus 2451: static int
1.295 djm 2452: channel_setup_fwd_listener(int type, const char *listen_addr,
2453: u_short listen_port, int *allocated_listen_port,
1.160 markus 2454: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2455: {
1.113 markus 2456: Channel *c;
1.226 djm 2457: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2458: struct addrinfo hints, *ai, *aitop;
1.212 djm 2459: const char *host, *addr;
1.35 markus 2460: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2461: in_port_t *lport_p;
1.25 markus 2462:
1.160 markus 2463: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2464: listen_addr : host_to_connect;
1.212 djm 2465: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2466:
1.160 markus 2467: if (host == NULL) {
2468: error("No forward host name.");
1.218 markus 2469: return 0;
1.73 markus 2470: }
1.294 djm 2471: if (strlen(host) >= NI_MAXHOST) {
1.87 markus 2472: error("Forward host name too long.");
1.218 markus 2473: return 0;
1.87 markus 2474: }
1.25 markus 2475:
1.28 markus 2476: /*
1.212 djm 2477: * Determine whether or not a port forward listens to loopback,
1.213 deraadt 2478: * specified address or wildcard. On the client, a specified bind
2479: * address will always override gateway_ports. On the server, a
2480: * gateway_ports of 1 (``yes'') will override the client's
2481: * specification and force a wildcard bind, whereas a value of 2
2482: * (``clientspecified'') will bind to whatever address the client
1.212 djm 2483: * asked for.
2484: *
2485: * Special-case listen_addrs are:
2486: *
2487: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2488: * "" (empty string), "*" -> wildcard v4/v6
2489: * "localhost" -> loopback v4/v6
2490: */
2491: addr = NULL;
2492: if (listen_addr == NULL) {
2493: /* No address specified: default to gateway_ports setting */
2494: if (gateway_ports)
2495: wildcard = 1;
2496: } else if (gateway_ports || is_client) {
2497: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
1.272 djm 2498: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
1.212 djm 2499: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2500: (!is_client && gateway_ports == 1))
2501: wildcard = 1;
2502: else if (strcmp(listen_addr, "localhost") != 0)
2503: addr = listen_addr;
2504: }
2505:
2506: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2507: type, wildcard, (addr == NULL) ? "NULL" : addr);
2508:
2509: /*
1.35 markus 2510: * getaddrinfo returns a loopback address if the hostname is
2511: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2512: */
1.35 markus 2513: memset(&hints, 0, sizeof(hints));
2514: hints.ai_family = IPv4or6;
1.212 djm 2515: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2516: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2517: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2518: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2519: if (addr == NULL) {
2520: /* This really shouldn't happen */
2521: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2522: ssh_gai_strerror(r));
1.212 djm 2523: } else {
1.218 markus 2524: error("channel_setup_fwd_listener: "
1.271 dtucker 2525: "getaddrinfo(%.64s): %s", addr,
2526: ssh_gai_strerror(r));
1.212 djm 2527: }
1.218 markus 2528: return 0;
1.212 djm 2529: }
1.295 djm 2530: if (allocated_listen_port != NULL)
2531: *allocated_listen_port = 0;
1.35 markus 2532: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2533: switch (ai->ai_family) {
2534: case AF_INET:
2535: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2536: sin_port;
2537: break;
2538: case AF_INET6:
2539: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2540: sin6_port;
2541: break;
2542: default:
1.35 markus 2543: continue;
1.295 djm 2544: }
2545: /*
2546: * If allocating a port for -R forwards, then use the
2547: * same port for all address families.
2548: */
2549: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2550: allocated_listen_port != NULL && *allocated_listen_port > 0)
2551: *lport_p = htons(*allocated_listen_port);
2552:
1.35 markus 2553: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2554: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2555: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2556: continue;
2557: }
2558: /* Create a port to listen for the host. */
1.297 reyk 2559: sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
2560: ai->ai_protocol, channel_rdomain);
1.35 markus 2561: if (sock < 0) {
2562: /* this is no error since kernel may not support ipv6 */
2563: verbose("socket: %.100s", strerror(errno));
2564: continue;
2565: }
1.226 djm 2566:
2567: channel_set_reuseaddr(sock);
1.182 stevesk 2568:
1.295 djm 2569: debug("Local forwarding listening on %s port %s.",
2570: ntop, strport);
1.35 markus 2571:
2572: /* Bind the socket to the address. */
2573: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2574: /* address can be in use ipv6 address is already bound */
2575: verbose("bind: %.100s", strerror(errno));
2576: close(sock);
2577: continue;
2578: }
2579: /* Start listening for connections on the socket. */
1.199 markus 2580: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2581: error("listen: %.100s", strerror(errno));
2582: close(sock);
2583: continue;
2584: }
1.295 djm 2585:
2586: /*
2587: * listen_port == 0 requests a dynamically allocated port -
2588: * record what we got.
2589: */
2590: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2591: allocated_listen_port != NULL &&
2592: *allocated_listen_port == 0) {
2593: *allocated_listen_port = get_sock_port(sock, 1);
2594: debug("Allocated listen port %d",
2595: *allocated_listen_port);
2596: }
2597:
1.35 markus 2598: /* Allocate a channel number for the socket. */
1.121 markus 2599: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2600: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2601: 0, "port listener", 1);
1.293 djm 2602: c->path = xstrdup(host);
1.113 markus 2603: c->host_port = port_to_connect;
2604: c->listening_port = listen_port;
1.35 markus 2605: success = 1;
2606: }
2607: if (success == 0)
1.160 markus 2608: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2609: listen_port);
1.35 markus 2610: freeaddrinfo(aitop);
1.87 markus 2611: return success;
1.25 markus 2612: }
1.1 deraadt 2613:
1.202 djm 2614: int
2615: channel_cancel_rport_listener(const char *host, u_short port)
2616: {
1.209 avsm 2617: u_int i;
2618: int found = 0;
1.202 djm 2619:
1.213 deraadt 2620: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2621: Channel *c = channels[i];
2622:
2623: if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
1.293 djm 2624: strcmp(c->path, host) == 0 && c->listening_port == port) {
1.210 djm 2625: debug2("%s: close channel %d", __func__, i);
1.202 djm 2626: channel_free(c);
2627: found = 1;
2628: }
2629: }
2630:
2631: return (found);
2632: }
2633:
1.160 markus 2634: /* protocol local port fwd, used by ssh (and sshd in v1) */
2635: int
1.212 djm 2636: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2637: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2638: {
2639: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.295 djm 2640: listen_host, listen_port, NULL, host_to_connect, port_to_connect,
1.212 djm 2641: gateway_ports);
1.160 markus 2642: }
2643:
2644: /* protocol v2 remote port fwd, used by sshd */
2645: int
2646: channel_setup_remote_fwd_listener(const char *listen_address,
1.295 djm 2647: u_short listen_port, int *allocated_listen_port, int gateway_ports)
1.160 markus 2648: {
2649: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
1.295 djm 2650: listen_address, listen_port, allocated_listen_port,
2651: NULL, 0, gateway_ports);
1.160 markus 2652: }
2653:
1.27 markus 2654: /*
2655: * Initiate forwarding of connections to port "port" on remote host through
2656: * the secure channel to host:port from local side.
2657: */
1.1 deraadt 2658:
1.253 markus 2659: int
1.212 djm 2660: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2661: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2662: {
1.153 markus 2663: int type, success = 0;
1.73 markus 2664:
1.25 markus 2665: /* Record locally that connection to this host/port is permitted. */
2666: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2667: fatal("channel_request_remote_forwarding: too many forwards");
2668:
2669: /* Send the forward request to the remote side. */
1.44 markus 2670: if (compat20) {
1.212 djm 2671: const char *address_to_bind;
1.267 djm 2672: if (listen_host == NULL) {
2673: if (datafellows & SSH_BUG_RFWD_ADDR)
2674: address_to_bind = "127.0.0.1";
2675: else
2676: address_to_bind = "localhost";
2677: } else if (*listen_host == '\0' ||
2678: strcmp(listen_host, "*") == 0) {
2679: if (datafellows & SSH_BUG_RFWD_ADDR)
2680: address_to_bind = "0.0.0.0";
2681: else
2682: address_to_bind = "";
2683: } else
1.212 djm 2684: address_to_bind = listen_host;
2685:
1.44 markus 2686: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2687: packet_put_cstring("tcpip-forward");
1.173 markus 2688: packet_put_char(1); /* boolean: want reply */
1.44 markus 2689: packet_put_cstring(address_to_bind);
2690: packet_put_int(listen_port);
1.73 markus 2691: packet_send();
2692: packet_write_wait();
2693: /* Assume that server accepts the request */
2694: success = 1;
1.44 markus 2695: } else {
2696: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2697: packet_put_int(listen_port);
2698: packet_put_cstring(host_to_connect);
1.44 markus 2699: packet_put_int(port_to_connect);
2700: packet_send();
2701: packet_write_wait();
1.73 markus 2702:
2703: /* Wait for response from the remote side. */
1.153 markus 2704: type = packet_read();
1.73 markus 2705: switch (type) {
2706: case SSH_SMSG_SUCCESS:
2707: success = 1;
2708: break;
2709: case SSH_SMSG_FAILURE:
2710: break;
2711: default:
2712: /* Unknown packet */
2713: packet_disconnect("Protocol error for port forward request:"
2714: "received packet type %d.", type);
2715: }
2716: }
2717: if (success) {
2718: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2719: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2720: permitted_opens[num_permitted_opens].listen_port = listen_port;
2721: num_permitted_opens++;
1.44 markus 2722: }
1.253 markus 2723: return (success ? 0 : -1);
1.1 deraadt 2724: }
2725:
1.27 markus 2726: /*
1.208 deraadt 2727: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 2728: * local side.
2729: */
2730: void
1.212 djm 2731: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 2732: {
2733: int i;
2734:
2735: if (!compat20)
2736: return;
2737:
2738: for (i = 0; i < num_permitted_opens; i++) {
1.208 deraadt 2739: if (permitted_opens[i].host_to_connect != NULL &&
1.202 djm 2740: permitted_opens[i].listen_port == port)
2741: break;
2742: }
2743: if (i >= num_permitted_opens) {
2744: debug("%s: requested forward not found", __func__);
2745: return;
2746: }
2747: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2748: packet_put_cstring("cancel-tcpip-forward");
2749: packet_put_char(0);
1.212 djm 2750: packet_put_cstring(host == NULL ? "" : host);
1.202 djm 2751: packet_put_int(port);
2752: packet_send();
2753:
2754: permitted_opens[i].listen_port = 0;
2755: permitted_opens[i].port_to_connect = 0;
1.227 stevesk 2756: xfree(permitted_opens[i].host_to_connect);
1.202 djm 2757: permitted_opens[i].host_to_connect = NULL;
2758: }
2759:
2760: /*
1.27 markus 2761: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2762: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 2763: * message if there was an error).
1.27 markus 2764: */
1.253 markus 2765: int
1.56 markus 2766: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2767: {
1.31 markus 2768: u_short port, host_port;
1.253 markus 2769: int success = 0;
1.25 markus 2770: char *hostname;
1.1 deraadt 2771:
1.25 markus 2772: /* Get arguments from the packet. */
2773: port = packet_get_int();
2774: hostname = packet_get_string(NULL);
2775: host_port = packet_get_int();
2776:
1.27 markus 2777: /*
2778: * Check that an unprivileged user is not trying to forward a
2779: * privileged port.
2780: */
1.25 markus 2781: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 2782: packet_disconnect(
2783: "Requested forwarding of port %d but user is not root.",
2784: port);
2785: if (host_port == 0)
2786: packet_disconnect("Dynamic forwarding denied.");
2787:
1.73 markus 2788: /* Initiate forwarding */
1.253 markus 2789: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 2790: host_port, gateway_ports);
1.25 markus 2791:
2792: /* Free the argument string. */
2793: xfree(hostname);
1.253 markus 2794:
2795: return (success ? 0 : -1);
1.1 deraadt 2796: }
2797:
1.99 markus 2798: /*
2799: * Permits opening to any host/port if permitted_opens[] is empty. This is
2800: * usually called by the server, because the user could connect to any port
2801: * anyway, and the server has no way to know but to trust the client anyway.
2802: */
2803: void
1.142 itojun 2804: channel_permit_all_opens(void)
1.99 markus 2805: {
2806: if (num_permitted_opens == 0)
2807: all_opens_permitted = 1;
2808: }
2809:
1.101 markus 2810: void
1.99 markus 2811: channel_add_permitted_opens(char *host, int port)
2812: {
2813: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1.253 markus 2814: fatal("channel_add_permitted_opens: too many forwards");
1.99 markus 2815: debug("allow port forwarding to host %s port %d", host, port);
2816:
2817: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2818: permitted_opens[num_permitted_opens].port_to_connect = port;
2819: num_permitted_opens++;
2820:
2821: all_opens_permitted = 0;
2822: }
2823:
1.258 dtucker 2824: int
1.257 dtucker 2825: channel_add_adm_permitted_opens(char *host, int port)
2826: {
2827: if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2828: fatal("channel_add_adm_permitted_opens: too many forwards");
1.258 dtucker 2829: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 2830:
2831: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
2832: = xstrdup(host);
2833: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.258 dtucker 2834: return ++num_adm_permitted_opens;
1.257 dtucker 2835: }
2836:
2837: void
1.99 markus 2838: channel_clear_permitted_opens(void)
2839: {
2840: int i;
2841:
2842: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2843: if (permitted_opens[i].host_to_connect != NULL)
2844: xfree(permitted_opens[i].host_to_connect);
1.99 markus 2845: num_permitted_opens = 0;
1.257 dtucker 2846: }
2847:
2848: void
2849: channel_clear_adm_permitted_opens(void)
2850: {
2851: int i;
1.99 markus 2852:
1.257 dtucker 2853: for (i = 0; i < num_adm_permitted_opens; i++)
2854: if (permitted_adm_opens[i].host_to_connect != NULL)
2855: xfree(permitted_adm_opens[i].host_to_connect);
2856: num_adm_permitted_opens = 0;
1.278 dtucker 2857: }
2858:
2859: void
2860: channel_print_adm_permitted_opens(void)
2861: {
1.286 djm 2862: int i;
1.278 dtucker 2863:
1.290 stevesk 2864: printf("permitopen");
1.288 stevesk 2865: if (num_adm_permitted_opens == 0) {
1.290 stevesk 2866: printf(" any\n");
1.288 stevesk 2867: return;
2868: }
1.278 dtucker 2869: for (i = 0; i < num_adm_permitted_opens; i++)
2870: if (permitted_adm_opens[i].host_to_connect != NULL)
2871: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
2872: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 2873: printf("\n");
1.99 markus 2874: }
2875:
1.276 djm 2876: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 2877: static int
1.276 djm 2878: connect_next(struct channel_connect *cctx)
1.41 markus 2879: {
1.276 djm 2880: int sock, saved_errno;
1.41 markus 2881: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2882:
1.276 djm 2883: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
2884: if (cctx->ai->ai_family != AF_INET &&
2885: cctx->ai->ai_family != AF_INET6)
1.41 markus 2886: continue;
1.276 djm 2887: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
2888: ntop, sizeof(ntop), strport, sizeof(strport),
2889: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
2890: error("connect_next: getnameinfo failed");
1.41 markus 2891: continue;
2892: }
1.297 reyk 2893: if ((sock = socket_rdomain(cctx->ai->ai_family,
2894: cctx->ai->ai_socktype, cctx->ai->ai_protocol,
2895: channel_rdomain)) == -1) {
1.276 djm 2896: if (cctx->ai->ai_next == NULL)
1.186 djm 2897: error("socket: %.100s", strerror(errno));
2898: else
2899: verbose("socket: %.100s", strerror(errno));
1.41 markus 2900: continue;
2901: }
1.205 djm 2902: if (set_nonblock(sock) == -1)
2903: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 2904: if (connect(sock, cctx->ai->ai_addr,
2905: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
2906: debug("connect_next: host %.100s ([%.100s]:%s): "
2907: "%.100s", cctx->host, ntop, strport,
1.41 markus 2908: strerror(errno));
1.276 djm 2909: saved_errno = errno;
1.41 markus 2910: close(sock);
1.276 djm 2911: errno = saved_errno;
1.89 stevesk 2912: continue; /* fail -- try next */
1.41 markus 2913: }
1.276 djm 2914: debug("connect_next: host %.100s ([%.100s]:%s) "
2915: "in progress, fd=%d", cctx->host, ntop, strport, sock);
2916: cctx->ai = cctx->ai->ai_next;
2917: set_nodelay(sock);
2918: return sock;
2919: }
2920: return -1;
2921: }
1.41 markus 2922:
1.276 djm 2923: static void
2924: channel_connect_ctx_free(struct channel_connect *cctx)
2925: {
2926: xfree(cctx->host);
2927: if (cctx->aitop)
2928: freeaddrinfo(cctx->aitop);
2929: bzero(cctx, sizeof(*cctx));
2930: cctx->host = NULL;
2931: cctx->ai = cctx->aitop = NULL;
2932: }
2933:
2934: /* Return CONNECTING channel to remote host, port */
2935: static Channel *
2936: connect_to(const char *host, u_short port, char *ctype, char *rname)
2937: {
2938: struct addrinfo hints;
2939: int gaierr;
2940: int sock = -1;
2941: char strport[NI_MAXSERV];
2942: struct channel_connect cctx;
2943: Channel *c;
2944:
1.284 djm 2945: memset(&cctx, 0, sizeof(cctx));
1.276 djm 2946: memset(&hints, 0, sizeof(hints));
2947: hints.ai_family = IPv4or6;
2948: hints.ai_socktype = SOCK_STREAM;
2949: snprintf(strport, sizeof strport, "%d", port);
2950: if ((gaierr = getaddrinfo(host, strport, &hints, &cctx.aitop)) != 0) {
2951: error("connect_to %.100s: unknown host (%s)", host,
2952: ssh_gai_strerror(gaierr));
2953: return NULL;
1.41 markus 2954: }
1.276 djm 2955:
2956: cctx.host = xstrdup(host);
2957: cctx.port = port;
2958: cctx.ai = cctx.aitop;
2959:
2960: if ((sock = connect_next(&cctx)) == -1) {
2961: error("connect to %.100s port %d failed: %s",
2962: host, port, strerror(errno));
2963: channel_connect_ctx_free(&cctx);
2964: return NULL;
1.41 markus 2965: }
1.276 djm 2966: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
2967: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
2968: c->connect_ctx = cctx;
2969: return c;
1.41 markus 2970: }
1.99 markus 2971:
1.276 djm 2972: Channel *
2973: channel_connect_by_listen_address(u_short listen_port, char *ctype, char *rname)
1.73 markus 2974: {
2975: int i;
1.99 markus 2976:
1.276 djm 2977: for (i = 0; i < num_permitted_opens; i++) {
1.202 djm 2978: if (permitted_opens[i].host_to_connect != NULL &&
1.276 djm 2979: permitted_opens[i].listen_port == listen_port) {
1.99 markus 2980: return connect_to(
1.73 markus 2981: permitted_opens[i].host_to_connect,
1.276 djm 2982: permitted_opens[i].port_to_connect, ctype, rname);
2983: }
2984: }
1.74 markus 2985: error("WARNING: Server requests forwarding for unknown listen_port %d",
2986: listen_port);
1.276 djm 2987: return NULL;
1.73 markus 2988: }
2989:
1.99 markus 2990: /* Check if connecting to that port is permitted and connect. */
1.276 djm 2991: Channel *
2992: channel_connect_to(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 2993: {
1.257 dtucker 2994: int i, permit, permit_adm = 1;
1.99 markus 2995:
2996: permit = all_opens_permitted;
2997: if (!permit) {
2998: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2999: if (permitted_opens[i].host_to_connect != NULL &&
3000: permitted_opens[i].port_to_connect == port &&
1.99 markus 3001: strcmp(permitted_opens[i].host_to_connect, host) == 0)
3002: permit = 1;
1.257 dtucker 3003: }
1.99 markus 3004:
1.257 dtucker 3005: if (num_adm_permitted_opens > 0) {
3006: permit_adm = 0;
3007: for (i = 0; i < num_adm_permitted_opens; i++)
3008: if (permitted_adm_opens[i].host_to_connect != NULL &&
3009: permitted_adm_opens[i].port_to_connect == port &&
3010: strcmp(permitted_adm_opens[i].host_to_connect, host)
3011: == 0)
3012: permit_adm = 1;
1.99 markus 3013: }
1.257 dtucker 3014:
3015: if (!permit || !permit_adm) {
1.188 itojun 3016: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3017: "but the request was denied.", host, port);
1.276 djm 3018: return NULL;
1.99 markus 3019: }
1.276 djm 3020: return connect_to(host, port, ctype, rname);
1.204 djm 3021: }
3022:
3023: void
3024: channel_send_window_changes(void)
3025: {
1.209 avsm 3026: u_int i;
1.204 djm 3027: struct winsize ws;
3028:
3029: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3030: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3031: channels[i]->type != SSH_CHANNEL_OPEN)
3032: continue;
3033: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3034: continue;
3035: channel_request_start(i, "window-change", 0);
1.238 deraadt 3036: packet_put_int((u_int)ws.ws_col);
3037: packet_put_int((u_int)ws.ws_row);
3038: packet_put_int((u_int)ws.ws_xpixel);
3039: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3040: packet_send();
3041: }
1.99 markus 3042: }
3043:
1.121 markus 3044: /* -- X11 forwarding */
1.1 deraadt 3045:
1.27 markus 3046: /*
3047: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3048: * Returns 0 and a suitable display number for the DISPLAY variable
3049: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3050: */
1.141 stevesk 3051: int
1.163 stevesk 3052: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3053: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3054: {
1.149 markus 3055: Channel *nc = NULL;
1.31 markus 3056: int display_number, sock;
3057: u_short port;
1.35 markus 3058: struct addrinfo hints, *ai, *aitop;
3059: char strport[NI_MAXSERV];
3060: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3061:
1.224 markus 3062: if (chanids == NULL)
3063: return -1;
3064:
1.33 markus 3065: for (display_number = x11_display_offset;
1.148 deraadt 3066: display_number < MAX_DISPLAYS;
3067: display_number++) {
1.25 markus 3068: port = 6000 + display_number;
1.35 markus 3069: memset(&hints, 0, sizeof(hints));
3070: hints.ai_family = IPv4or6;
1.163 stevesk 3071: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3072: hints.ai_socktype = SOCK_STREAM;
3073: snprintf(strport, sizeof strport, "%d", port);
3074: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3075: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3076: return -1;
1.25 markus 3077: }
1.35 markus 3078: for (ai = aitop; ai; ai = ai->ai_next) {
3079: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3080: continue;
1.297 reyk 3081: sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
3082: ai->ai_protocol, channel_rdomain);
1.35 markus 3083: if (sock < 0) {
3084: error("socket: %.100s", strerror(errno));
1.203 markus 3085: freeaddrinfo(aitop);
1.141 stevesk 3086: return -1;
1.35 markus 3087: }
1.226 djm 3088: channel_set_reuseaddr(sock);
1.35 markus 3089: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3090: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3091: close(sock);
1.183 itojun 3092:
1.35 markus 3093: for (n = 0; n < num_socks; n++) {
3094: close(socks[n]);
3095: }
3096: num_socks = 0;
3097: break;
3098: }
3099: socks[num_socks++] = sock;
3100: if (num_socks == NUM_SOCKS)
3101: break;
1.25 markus 3102: }
1.83 stevesk 3103: freeaddrinfo(aitop);
1.35 markus 3104: if (num_socks > 0)
3105: break;
1.25 markus 3106: }
3107: if (display_number >= MAX_DISPLAYS) {
3108: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3109: return -1;
1.25 markus 3110: }
3111: /* Start listening for connections on the socket. */
1.35 markus 3112: for (n = 0; n < num_socks; n++) {
3113: sock = socks[n];
1.199 markus 3114: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3115: error("listen: %.100s", strerror(errno));
3116: close(sock);
1.141 stevesk 3117: return -1;
1.35 markus 3118: }
1.25 markus 3119: }
1.35 markus 3120:
3121: /* Allocate a channel for each socket. */
1.242 djm 3122: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3123: for (n = 0; n < num_socks; n++) {
3124: sock = socks[n];
1.149 markus 3125: nc = channel_new("x11 listener",
1.51 markus 3126: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3127: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3128: 0, "X11 inet listener", 1);
1.167 markus 3129: nc->single_connection = single_connection;
1.224 markus 3130: (*chanids)[n] = nc->self;
1.35 markus 3131: }
1.224 markus 3132: (*chanids)[n] = -1;
1.1 deraadt 3133:
1.141 stevesk 3134: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3135: *display_numberp = display_number;
3136: return (0);
1.1 deraadt 3137: }
3138:
1.127 itojun 3139: static int
1.77 markus 3140: connect_local_xsocket(u_int dnr)
1.1 deraadt 3141: {
1.25 markus 3142: int sock;
3143: struct sockaddr_un addr;
3144:
1.147 stevesk 3145: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3146: if (sock < 0)
3147: error("socket: %.100s", strerror(errno));
3148: memset(&addr, 0, sizeof(addr));
3149: addr.sun_family = AF_UNIX;
3150: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3151: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3152: return sock;
3153: close(sock);
1.25 markus 3154: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3155: return -1;
1.1 deraadt 3156: }
3157:
1.51 markus 3158: int
3159: x11_connect_display(void)
1.1 deraadt 3160: {
1.248 deraadt 3161: u_int display_number;
1.25 markus 3162: const char *display;
1.51 markus 3163: char buf[1024], *cp;
1.35 markus 3164: struct addrinfo hints, *ai, *aitop;
3165: char strport[NI_MAXSERV];
1.248 deraadt 3166: int gaierr, sock = 0;
1.25 markus 3167:
3168: /* Try to open a socket for the local X server. */
3169: display = getenv("DISPLAY");
3170: if (!display) {
3171: error("DISPLAY not set.");
1.51 markus 3172: return -1;
1.25 markus 3173: }
1.27 markus 3174: /*
3175: * Now we decode the value of the DISPLAY variable and make a
3176: * connection to the real X server.
3177: */
3178:
3179: /*
3180: * Check if it is a unix domain socket. Unix domain displays are in
3181: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3182: */
1.25 markus 3183: if (strncmp(display, "unix:", 5) == 0 ||
3184: display[0] == ':') {
3185: /* Connect to the unix domain socket. */
1.248 deraadt 3186: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3187: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3188: display);
1.51 markus 3189: return -1;
1.25 markus 3190: }
3191: /* Create a socket. */
3192: sock = connect_local_xsocket(display_number);
3193: if (sock < 0)
1.51 markus 3194: return -1;
1.25 markus 3195:
3196: /* OK, we now have a connection to the display. */
1.51 markus 3197: return sock;
1.25 markus 3198: }
1.27 markus 3199: /*
3200: * Connect to an inet socket. The DISPLAY value is supposedly
3201: * hostname:d[.s], where hostname may also be numeric IP address.
3202: */
1.145 stevesk 3203: strlcpy(buf, display, sizeof(buf));
1.25 markus 3204: cp = strchr(buf, ':');
3205: if (!cp) {
3206: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3207: return -1;
1.25 markus 3208: }
3209: *cp = 0;
1.27 markus 3210: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 3211: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 3212: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3213: display);
1.51 markus 3214: return -1;
1.25 markus 3215: }
1.35 markus 3216:
3217: /* Look up the host address */
3218: memset(&hints, 0, sizeof(hints));
3219: hints.ai_family = IPv4or6;
3220: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 3221: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 3222: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3223: error("%.100s: unknown host. (%s)", buf,
3224: ssh_gai_strerror(gaierr));
1.51 markus 3225: return -1;
1.25 markus 3226: }
1.35 markus 3227: for (ai = aitop; ai; ai = ai->ai_next) {
3228: /* Create a socket. */
1.297 reyk 3229: sock = socket_rdomain(ai->ai_family, ai->ai_socktype,
3230: ai->ai_protocol, channel_rdomain);
1.35 markus 3231: if (sock < 0) {
1.194 markus 3232: debug2("socket: %.100s", strerror(errno));
1.41 markus 3233: continue;
3234: }
3235: /* Connect it to the display. */
3236: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 3237: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 3238: 6000 + display_number, strerror(errno));
3239: close(sock);
3240: continue;
3241: }
3242: /* Success */
3243: break;
1.35 markus 3244: }
3245: freeaddrinfo(aitop);
3246: if (!ai) {
1.248 deraadt 3247: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3248: strerror(errno));
1.51 markus 3249: return -1;
1.25 markus 3250: }
1.162 stevesk 3251: set_nodelay(sock);
1.51 markus 3252: return sock;
3253: }
3254:
3255: /*
3256: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3257: * the remote channel number. We should do whatever we want, and respond
3258: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3259: */
3260:
1.259 stevesk 3261: /* ARGSUSED */
1.51 markus 3262: void
1.154 markus 3263: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3264: {
1.113 markus 3265: Channel *c = NULL;
3266: int remote_id, sock = 0;
1.51 markus 3267: char *remote_host;
1.25 markus 3268:
1.113 markus 3269: debug("Received X11 open request.");
1.51 markus 3270:
1.113 markus 3271: remote_id = packet_get_int();
1.121 markus 3272:
3273: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3274: remote_host = packet_get_string(NULL);
1.51 markus 3275: } else {
3276: remote_host = xstrdup("unknown (remote did not supply name)");
3277: }
1.152 markus 3278: packet_check_eom();
1.25 markus 3279:
1.51 markus 3280: /* Obtain a connection to the real X display. */
3281: sock = x11_connect_display();
1.113 markus 3282: if (sock != -1) {
3283: /* Allocate a channel for this connection. */
3284: c = channel_new("connected x11 socket",
3285: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3286: remote_host, 1);
1.167 markus 3287: c->remote_id = remote_id;
3288: c->force_drain = 1;
1.113 markus 3289: }
1.190 markus 3290: xfree(remote_host);
1.113 markus 3291: if (c == NULL) {
1.51 markus 3292: /* Send refusal to the remote host. */
3293: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3294: packet_put_int(remote_id);
1.51 markus 3295: } else {
3296: /* Send a confirmation to the remote host. */
3297: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3298: packet_put_int(remote_id);
3299: packet_put_int(c->self);
1.51 markus 3300: }
1.113 markus 3301: packet_send();
1.72 markus 3302: }
3303:
3304: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 3305: /* ARGSUSED */
1.72 markus 3306: void
1.154 markus 3307: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3308: {
3309: int rchan = packet_get_int();
1.180 deraadt 3310:
1.143 deraadt 3311: switch (type) {
1.72 markus 3312: case SSH_SMSG_AGENT_OPEN:
3313: error("Warning: ssh server tried agent forwarding.");
3314: break;
3315: case SSH_SMSG_X11_OPEN:
3316: error("Warning: ssh server tried X11 forwarding.");
3317: break;
3318: default:
1.154 markus 3319: error("deny_input_open: type %d", type);
1.72 markus 3320: break;
3321: }
1.230 stevesk 3322: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3323: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3324: packet_put_int(rchan);
3325: packet_send();
1.1 deraadt 3326: }
3327:
1.27 markus 3328: /*
3329: * Requests forwarding of X11 connections, generates fake authentication
3330: * data, and enables authentication spoofing.
1.121 markus 3331: * This should be called in the client only.
1.27 markus 3332: */
1.49 markus 3333: void
1.215 djm 3334: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.51 markus 3335: const char *proto, const char *data)
1.1 deraadt 3336: {
1.77 markus 3337: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3338: u_int i, value;
1.25 markus 3339: char *new_data;
3340: int screen_number;
3341: const char *cp;
1.207 avsm 3342: u_int32_t rnd = 0;
1.25 markus 3343:
1.220 markus 3344: if (x11_saved_display == NULL)
3345: x11_saved_display = xstrdup(disp);
3346: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3347: error("x11_request_forwarding_with_spoofing: different "
3348: "$DISPLAY already forwarded");
3349: return;
3350: }
3351:
1.266 djm 3352: cp = strchr(disp, ':');
1.25 markus 3353: if (cp)
3354: cp = strchr(cp, '.');
3355: if (cp)
1.245 deraadt 3356: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3357: else
3358: screen_number = 0;
3359:
1.219 djm 3360: if (x11_saved_proto == NULL) {
3361: /* Save protocol name. */
3362: x11_saved_proto = xstrdup(proto);
3363: /*
1.221 djm 3364: * Extract real authentication data and generate fake data
1.219 djm 3365: * of the same length.
3366: */
3367: x11_saved_data = xmalloc(data_len);
3368: x11_fake_data = xmalloc(data_len);
3369: for (i = 0; i < data_len; i++) {
3370: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3371: fatal("x11_request_forwarding: bad "
3372: "authentication data: %.100s", data);
3373: if (i % 4 == 0)
3374: rnd = arc4random();
3375: x11_saved_data[i] = value;
3376: x11_fake_data[i] = rnd & 0xff;
3377: rnd >>= 8;
3378: }
3379: x11_saved_data_len = data_len;
3380: x11_fake_data_len = data_len;
1.25 markus 3381: }
3382:
3383: /* Convert the fake data into hex. */
1.219 djm 3384: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3385:
3386: /* Send the request packet. */
1.51 markus 3387: if (compat20) {
3388: channel_request_start(client_session_id, "x11-req", 0);
3389: packet_put_char(0); /* XXX bool single connection */
3390: } else {
3391: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3392: }
3393: packet_put_cstring(proto);
3394: packet_put_cstring(new_data);
1.25 markus 3395: packet_put_int(screen_number);
3396: packet_send();
3397: packet_write_wait();
3398: xfree(new_data);
1.1 deraadt 3399: }
3400:
1.121 markus 3401:
3402: /* -- agent forwarding */
3403:
1.1 deraadt 3404: /* Sends a message to the server to request authentication fd forwarding. */
3405:
1.49 markus 3406: void
1.142 itojun 3407: auth_request_forwarding(void)
1.1 deraadt 3408: {
1.25 markus 3409: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3410: packet_send();
3411: packet_write_wait();
1.1 deraadt 3412: }
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