Annotation of src/usr.bin/ssh/channels.c, Revision 1.275
1.275 ! djm 1: /* $OpenBSD: channels.c,v 1.274 2008/05/08 06:59:01 markus Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.234 stevesk 43: #include <sys/ioctl.h>
1.235 stevesk 44: #include <sys/un.h>
1.251 stevesk 45: #include <sys/socket.h>
1.261 stevesk 46: #include <sys/time.h>
1.275 ! djm 47: #include <sys/queue.h>
1.251 stevesk 48:
49: #include <netinet/in.h>
50: #include <arpa/inet.h>
1.233 stevesk 51:
1.254 stevesk 52: #include <errno.h>
1.255 stevesk 53: #include <netdb.h>
1.263 stevesk 54: #include <stdio.h>
1.262 stevesk 55: #include <stdlib.h>
1.260 stevesk 56: #include <string.h>
1.233 stevesk 57: #include <termios.h>
1.256 stevesk 58: #include <unistd.h>
1.265 deraadt 59: #include <stdarg.h>
1.1 deraadt 60:
1.265 deraadt 61: #include "xmalloc.h"
1.1 deraadt 62: #include "ssh.h"
1.82 markus 63: #include "ssh1.h"
64: #include "ssh2.h"
1.1 deraadt 65: #include "packet.h"
1.82 markus 66: #include "log.h"
67: #include "misc.h"
1.265 deraadt 68: #include "buffer.h"
1.14 markus 69: #include "channels.h"
70: #include "compat.h"
1.82 markus 71: #include "canohost.h"
1.64 markus 72: #include "key.h"
73: #include "authfd.h"
1.147 stevesk 74: #include "pathnames.h"
1.1 deraadt 75:
1.121 markus 76: /* -- channel core */
1.12 markus 77:
1.27 markus 78: /*
79: * Pointer to an array containing all allocated channels. The array is
80: * dynamically extended as needed.
81: */
1.113 markus 82: static Channel **channels = NULL;
1.1 deraadt 83:
1.27 markus 84: /*
85: * Size of the channel array. All slots of the array must always be
1.113 markus 86: * initialized (at least the type field); unused slots set to NULL
1.27 markus 87: */
1.209 avsm 88: static u_int channels_alloc = 0;
1.1 deraadt 89:
1.27 markus 90: /*
91: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 92: * updated in channel_new.
1.27 markus 93: */
1.84 markus 94: static int channel_max_fd = 0;
1.1 deraadt 95:
96:
1.121 markus 97: /* -- tcp forwarding */
1.1 deraadt 98:
1.27 markus 99: /*
100: * Data structure for storing which hosts are permitted for forward requests.
101: * The local sides of any remote forwards are stored in this array to prevent
102: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
103: * network (which might be behind a firewall).
104: */
1.25 markus 105: typedef struct {
1.41 markus 106: char *host_to_connect; /* Connect to 'host'. */
107: u_short port_to_connect; /* Connect to 'port'. */
108: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 109: } ForwardPermission;
110:
1.257 dtucker 111: /* List of all permitted host/port pairs to connect by the user. */
1.1 deraadt 112: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 113:
1.257 dtucker 114: /* List of all permitted host/port pairs to connect by the admin. */
115: static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
116:
117: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 118: static int num_permitted_opens = 0;
1.257 dtucker 119:
120: /* Number of permitted host/port pair in the array permitted by the admin. */
121: static int num_adm_permitted_opens = 0;
122:
1.27 markus 123: /*
124: * If this is true, all opens are permitted. This is the case on the server
125: * on which we have to trust the client anyway, and the user could do
126: * anything after logging in anyway.
127: */
1.1 deraadt 128: static int all_opens_permitted = 0;
129:
1.121 markus 130:
131: /* -- X11 forwarding */
132:
133: /* Maximum number of fake X11 displays to try. */
134: #define MAX_DISPLAYS 1000
135:
1.219 djm 136: /* Saved X11 local (client) display. */
137: static char *x11_saved_display = NULL;
138:
1.121 markus 139: /* Saved X11 authentication protocol name. */
140: static char *x11_saved_proto = NULL;
141:
142: /* Saved X11 authentication data. This is the real data. */
143: static char *x11_saved_data = NULL;
144: static u_int x11_saved_data_len = 0;
145:
146: /*
147: * Fake X11 authentication data. This is what the server will be sending us;
148: * we should replace any occurrences of this by the real data.
149: */
1.240 deraadt 150: static u_char *x11_fake_data = NULL;
1.121 markus 151: static u_int x11_fake_data_len;
152:
153:
154: /* -- agent forwarding */
155:
156: #define NUM_SOCKS 10
157:
1.82 markus 158: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 159: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 160:
1.121 markus 161: /* helper */
1.127 itojun 162: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 163:
1.121 markus 164: /* -- channel core */
1.41 markus 165:
166: Channel *
1.229 markus 167: channel_by_id(int id)
1.41 markus 168: {
169: Channel *c;
1.113 markus 170:
1.209 avsm 171: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 172: logit("channel_by_id: %d: bad id", id);
1.41 markus 173: return NULL;
174: }
1.113 markus 175: c = channels[id];
176: if (c == NULL) {
1.229 markus 177: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 178: return NULL;
179: }
180: return c;
1.55 markus 181: }
182:
1.27 markus 183: /*
1.229 markus 184: * Returns the channel if it is allowed to receive protocol messages.
185: * Private channels, like listening sockets, may not receive messages.
186: */
187: Channel *
188: channel_lookup(int id)
189: {
190: Channel *c;
191:
192: if ((c = channel_by_id(id)) == NULL)
193: return (NULL);
194:
1.237 deraadt 195: switch (c->type) {
1.229 markus 196: case SSH_CHANNEL_X11_OPEN:
197: case SSH_CHANNEL_LARVAL:
198: case SSH_CHANNEL_CONNECTING:
199: case SSH_CHANNEL_DYNAMIC:
200: case SSH_CHANNEL_OPENING:
201: case SSH_CHANNEL_OPEN:
202: case SSH_CHANNEL_INPUT_DRAINING:
203: case SSH_CHANNEL_OUTPUT_DRAINING:
204: return (c);
205: }
206: logit("Non-public channel %d, type %d.", id, c->type);
207: return (NULL);
208: }
209:
210: /*
1.55 markus 211: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 212: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 213: */
1.127 itojun 214: static void
1.71 markus 215: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
216: int extusage, int nonblock)
1.1 deraadt 217: {
1.25 markus 218: /* Update the maximum file descriptor value. */
1.84 markus 219: channel_max_fd = MAX(channel_max_fd, rfd);
220: channel_max_fd = MAX(channel_max_fd, wfd);
221: channel_max_fd = MAX(channel_max_fd, efd);
222:
1.27 markus 223: /* XXX set close-on-exec -markus */
1.55 markus 224:
1.52 markus 225: c->rfd = rfd;
226: c->wfd = wfd;
227: c->sock = (rfd == wfd) ? rfd : -1;
1.204 djm 228: c->ctl_fd = -1; /* XXX: set elsewhere */
1.52 markus 229: c->efd = efd;
230: c->extended_usage = extusage;
1.71 markus 231:
1.91 markus 232: /* XXX ugly hack: nonblock is only set by the server */
233: if (nonblock && isatty(c->rfd)) {
1.194 markus 234: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 235: c->isatty = 1;
236: if (!isatty(c->wfd)) {
1.94 markus 237: error("channel %d: wfd %d is not a tty?",
1.91 markus 238: c->self, c->wfd);
239: }
240: } else {
241: c->isatty = 0;
242: }
243:
1.71 markus 244: /* enable nonblocking mode */
245: if (nonblock) {
246: if (rfd != -1)
247: set_nonblock(rfd);
248: if (wfd != -1)
249: set_nonblock(wfd);
250: if (efd != -1)
251: set_nonblock(efd);
252: }
1.52 markus 253: }
254:
255: /*
256: * Allocate a new channel object and set its type and socket. This will cause
257: * remote_name to be freed.
258: */
1.113 markus 259: Channel *
1.52 markus 260: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 261: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 262: {
1.209 avsm 263: int found;
264: u_int i;
1.52 markus 265: Channel *c;
1.25 markus 266:
267: /* Do initial allocation if this is the first call. */
268: if (channels_alloc == 0) {
269: channels_alloc = 10;
1.242 djm 270: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 271: for (i = 0; i < channels_alloc; i++)
1.113 markus 272: channels[i] = NULL;
1.25 markus 273: }
274: /* Try to find a free slot where to put the new channel. */
275: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 276: if (channels[i] == NULL) {
1.25 markus 277: /* Found a free slot. */
1.209 avsm 278: found = (int)i;
1.25 markus 279: break;
280: }
1.209 avsm 281: if (found < 0) {
1.27 markus 282: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 283: found = channels_alloc;
1.179 markus 284: if (channels_alloc > 10000)
285: fatal("channel_new: internal error: channels_alloc %d "
286: "too big.", channels_alloc);
1.243 djm 287: channels = xrealloc(channels, channels_alloc + 10,
288: sizeof(Channel *));
1.195 markus 289: channels_alloc += 10;
1.70 markus 290: debug2("channel: expanding %d", channels_alloc);
1.25 markus 291: for (i = found; i < channels_alloc; i++)
1.113 markus 292: channels[i] = NULL;
1.25 markus 293: }
1.113 markus 294: /* Initialize and return new channel. */
1.242 djm 295: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 296: buffer_init(&c->input);
297: buffer_init(&c->output);
1.41 markus 298: buffer_init(&c->extended);
1.159 markus 299: c->ostate = CHAN_OUTPUT_OPEN;
300: c->istate = CHAN_INPUT_OPEN;
301: c->flags = 0;
1.71 markus 302: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
1.25 markus 303: c->self = found;
304: c->type = type;
1.41 markus 305: c->ctype = ctype;
1.51 markus 306: c->local_window = window;
307: c->local_window_max = window;
308: c->local_consumed = 0;
309: c->local_maxpacket = maxpack;
1.25 markus 310: c->remote_id = -1;
1.190 markus 311: c->remote_name = xstrdup(remote_name);
1.41 markus 312: c->remote_window = 0;
313: c->remote_maxpacket = 0;
1.133 markus 314: c->force_drain = 0;
1.149 markus 315: c->single_connection = 0;
1.131 markus 316: c->detach_user = NULL;
1.225 djm 317: c->detach_close = 0;
1.275 ! djm 318: c->open_confirm = NULL;
! 319: c->open_confirm_ctx = NULL;
1.65 markus 320: c->input_filter = NULL;
1.231 reyk 321: c->output_filter = NULL;
1.275 ! djm 322: TAILQ_INIT(&c->status_confirms);
1.25 markus 323: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 324: return c;
1.1 deraadt 325: }
1.52 markus 326:
1.132 markus 327: static int
328: channel_find_maxfd(void)
329: {
1.209 avsm 330: u_int i;
331: int max = 0;
1.132 markus 332: Channel *c;
333:
334: for (i = 0; i < channels_alloc; i++) {
335: c = channels[i];
336: if (c != NULL) {
337: max = MAX(max, c->rfd);
338: max = MAX(max, c->wfd);
339: max = MAX(max, c->efd);
340: }
341: }
342: return max;
343: }
344:
345: int
346: channel_close_fd(int *fdp)
347: {
348: int ret = 0, fd = *fdp;
349:
350: if (fd != -1) {
351: ret = close(fd);
352: *fdp = -1;
353: if (fd == channel_max_fd)
354: channel_max_fd = channel_find_maxfd();
355: }
356: return ret;
357: }
358:
1.52 markus 359: /* Close all channel fd/socket. */
1.127 itojun 360: static void
1.52 markus 361: channel_close_fds(Channel *c)
362: {
1.204 djm 363: debug3("channel %d: close_fds r %d w %d e %d c %d",
364: c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
1.118 markus 365:
1.132 markus 366: channel_close_fd(&c->sock);
1.204 djm 367: channel_close_fd(&c->ctl_fd);
1.132 markus 368: channel_close_fd(&c->rfd);
369: channel_close_fd(&c->wfd);
370: channel_close_fd(&c->efd);
1.121 markus 371: }
372:
373: /* Free the channel and close its fd/socket. */
374: void
375: channel_free(Channel *c)
376: {
377: char *s;
1.209 avsm 378: u_int i, n;
1.275 ! djm 379: struct channel_confirm *cc;
1.121 markus 380:
381: for (n = 0, i = 0; i < channels_alloc; i++)
382: if (channels[i])
383: n++;
1.209 avsm 384: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 385: c->remote_name ? c->remote_name : "???", n);
386:
387: s = channel_open_message();
1.194 markus 388: debug3("channel %d: status: %s", c->self, s);
1.121 markus 389: xfree(s);
390:
391: if (c->sock != -1)
392: shutdown(c->sock, SHUT_RDWR);
1.204 djm 393: if (c->ctl_fd != -1)
394: shutdown(c->ctl_fd, SHUT_RDWR);
1.121 markus 395: channel_close_fds(c);
396: buffer_free(&c->input);
397: buffer_free(&c->output);
398: buffer_free(&c->extended);
399: if (c->remote_name) {
400: xfree(c->remote_name);
401: c->remote_name = NULL;
402: }
1.275 ! djm 403: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
! 404: if (cc->abandon_cb != NULL)
! 405: cc->abandon_cb(c, cc->ctx);
! 406: TAILQ_REMOVE(&c->status_confirms, cc, entry);
! 407: bzero(cc, sizeof(*cc));
! 408: xfree(cc);
! 409: }
1.121 markus 410: channels[c->self] = NULL;
411: xfree(c);
412: }
413:
414: void
1.126 markus 415: channel_free_all(void)
1.121 markus 416: {
1.209 avsm 417: u_int i;
1.121 markus 418:
1.126 markus 419: for (i = 0; i < channels_alloc; i++)
420: if (channels[i] != NULL)
421: channel_free(channels[i]);
1.131 markus 422: }
423:
1.121 markus 424: /*
425: * Closes the sockets/fds of all channels. This is used to close extra file
426: * descriptors after a fork.
427: */
428: void
1.142 itojun 429: channel_close_all(void)
1.121 markus 430: {
1.209 avsm 431: u_int i;
1.121 markus 432:
433: for (i = 0; i < channels_alloc; i++)
434: if (channels[i] != NULL)
435: channel_close_fds(channels[i]);
436: }
437:
438: /*
1.131 markus 439: * Stop listening to channels.
440: */
441: void
442: channel_stop_listening(void)
443: {
1.209 avsm 444: u_int i;
1.131 markus 445: Channel *c;
446:
447: for (i = 0; i < channels_alloc; i++) {
448: c = channels[i];
449: if (c != NULL) {
450: switch (c->type) {
451: case SSH_CHANNEL_AUTH_SOCKET:
452: case SSH_CHANNEL_PORT_LISTENER:
453: case SSH_CHANNEL_RPORT_LISTENER:
454: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 455: channel_close_fd(&c->sock);
1.131 markus 456: channel_free(c);
457: break;
458: }
459: }
460: }
461: }
462:
463: /*
1.121 markus 464: * Returns true if no channel has too much buffered data, and false if one or
465: * more channel is overfull.
466: */
467: int
1.142 itojun 468: channel_not_very_much_buffered_data(void)
1.121 markus 469: {
470: u_int i;
471: Channel *c;
472:
473: for (i = 0; i < channels_alloc; i++) {
474: c = channels[i];
475: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 476: #if 0
477: if (!compat20 &&
478: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 479: debug2("channel %d: big input buffer %d",
1.121 markus 480: c->self, buffer_len(&c->input));
481: return 0;
482: }
1.136 markus 483: #endif
1.121 markus 484: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 485: debug2("channel %d: big output buffer %u > %u",
1.136 markus 486: c->self, buffer_len(&c->output),
487: packet_get_maxsize());
1.121 markus 488: return 0;
489: }
490: }
491: }
492: return 1;
493: }
494:
495: /* Returns true if any channel is still open. */
496: int
1.142 itojun 497: channel_still_open(void)
1.121 markus 498: {
1.209 avsm 499: u_int i;
1.121 markus 500: Channel *c;
501:
502: for (i = 0; i < channels_alloc; i++) {
503: c = channels[i];
504: if (c == NULL)
505: continue;
506: switch (c->type) {
507: case SSH_CHANNEL_X11_LISTENER:
508: case SSH_CHANNEL_PORT_LISTENER:
509: case SSH_CHANNEL_RPORT_LISTENER:
510: case SSH_CHANNEL_CLOSED:
511: case SSH_CHANNEL_AUTH_SOCKET:
512: case SSH_CHANNEL_DYNAMIC:
513: case SSH_CHANNEL_CONNECTING:
514: case SSH_CHANNEL_ZOMBIE:
515: continue;
516: case SSH_CHANNEL_LARVAL:
517: if (!compat20)
518: fatal("cannot happen: SSH_CHANNEL_LARVAL");
519: continue;
520: case SSH_CHANNEL_OPENING:
521: case SSH_CHANNEL_OPEN:
522: case SSH_CHANNEL_X11_OPEN:
523: return 1;
524: case SSH_CHANNEL_INPUT_DRAINING:
525: case SSH_CHANNEL_OUTPUT_DRAINING:
526: if (!compat13)
527: fatal("cannot happen: OUT_DRAIN");
528: return 1;
529: default:
530: fatal("channel_still_open: bad channel type %d", c->type);
531: /* NOTREACHED */
532: }
533: }
534: return 0;
535: }
536:
537: /* Returns the id of an open channel suitable for keepaliving */
538: int
1.142 itojun 539: channel_find_open(void)
1.121 markus 540: {
1.209 avsm 541: u_int i;
1.121 markus 542: Channel *c;
543:
544: for (i = 0; i < channels_alloc; i++) {
545: c = channels[i];
1.206 djm 546: if (c == NULL || c->remote_id < 0)
1.121 markus 547: continue;
548: switch (c->type) {
549: case SSH_CHANNEL_CLOSED:
550: case SSH_CHANNEL_DYNAMIC:
551: case SSH_CHANNEL_X11_LISTENER:
552: case SSH_CHANNEL_PORT_LISTENER:
553: case SSH_CHANNEL_RPORT_LISTENER:
554: case SSH_CHANNEL_OPENING:
555: case SSH_CHANNEL_CONNECTING:
556: case SSH_CHANNEL_ZOMBIE:
557: continue;
558: case SSH_CHANNEL_LARVAL:
559: case SSH_CHANNEL_AUTH_SOCKET:
560: case SSH_CHANNEL_OPEN:
561: case SSH_CHANNEL_X11_OPEN:
562: return i;
563: case SSH_CHANNEL_INPUT_DRAINING:
564: case SSH_CHANNEL_OUTPUT_DRAINING:
565: if (!compat13)
566: fatal("cannot happen: OUT_DRAIN");
567: return i;
568: default:
569: fatal("channel_find_open: bad channel type %d", c->type);
570: /* NOTREACHED */
571: }
572: }
573: return -1;
574: }
575:
576:
577: /*
578: * Returns a message describing the currently open forwarded connections,
579: * suitable for sending to the client. The message contains crlf pairs for
580: * newlines.
581: */
582: char *
1.142 itojun 583: channel_open_message(void)
1.121 markus 584: {
585: Buffer buffer;
586: Channel *c;
587: char buf[1024], *cp;
1.209 avsm 588: u_int i;
1.121 markus 589:
590: buffer_init(&buffer);
591: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
592: buffer_append(&buffer, buf, strlen(buf));
593: for (i = 0; i < channels_alloc; i++) {
594: c = channels[i];
595: if (c == NULL)
596: continue;
597: switch (c->type) {
598: case SSH_CHANNEL_X11_LISTENER:
599: case SSH_CHANNEL_PORT_LISTENER:
600: case SSH_CHANNEL_RPORT_LISTENER:
601: case SSH_CHANNEL_CLOSED:
602: case SSH_CHANNEL_AUTH_SOCKET:
603: case SSH_CHANNEL_ZOMBIE:
604: continue;
605: case SSH_CHANNEL_LARVAL:
606: case SSH_CHANNEL_OPENING:
607: case SSH_CHANNEL_CONNECTING:
608: case SSH_CHANNEL_DYNAMIC:
609: case SSH_CHANNEL_OPEN:
610: case SSH_CHANNEL_X11_OPEN:
611: case SSH_CHANNEL_INPUT_DRAINING:
612: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 613: snprintf(buf, sizeof buf,
614: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
1.121 markus 615: c->self, c->remote_name,
616: c->type, c->remote_id,
617: c->istate, buffer_len(&c->input),
618: c->ostate, buffer_len(&c->output),
1.204 djm 619: c->rfd, c->wfd, c->ctl_fd);
1.121 markus 620: buffer_append(&buffer, buf, strlen(buf));
621: continue;
622: default:
623: fatal("channel_open_message: bad channel type %d", c->type);
624: /* NOTREACHED */
625: }
626: }
627: buffer_append(&buffer, "\0", 1);
628: cp = xstrdup(buffer_ptr(&buffer));
629: buffer_free(&buffer);
630: return cp;
631: }
632:
633: void
634: channel_send_open(int id)
635: {
636: Channel *c = channel_lookup(id);
1.180 deraadt 637:
1.121 markus 638: if (c == NULL) {
1.188 itojun 639: logit("channel_send_open: %d: bad id", id);
1.121 markus 640: return;
641: }
1.184 markus 642: debug2("channel %d: send open", id);
1.121 markus 643: packet_start(SSH2_MSG_CHANNEL_OPEN);
644: packet_put_cstring(c->ctype);
645: packet_put_int(c->self);
646: packet_put_int(c->local_window);
647: packet_put_int(c->local_maxpacket);
648: packet_send();
649: }
650:
651: void
1.184 markus 652: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 653: {
1.184 markus 654: Channel *c = channel_lookup(id);
1.180 deraadt 655:
1.121 markus 656: if (c == NULL) {
1.188 itojun 657: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 658: return;
659: }
1.204 djm 660: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 661: packet_start(SSH2_MSG_CHANNEL_REQUEST);
662: packet_put_int(c->remote_id);
663: packet_put_cstring(service);
664: packet_put_char(wantconfirm);
665: }
1.241 deraadt 666:
1.121 markus 667: void
1.275 ! djm 668: channel_register_status_confirm(int id, channel_confirm_cb *cb,
! 669: channel_confirm_abandon_cb *abandon_cb, void *ctx)
! 670: {
! 671: struct channel_confirm *cc;
! 672: Channel *c;
! 673:
! 674: if ((c = channel_lookup(id)) == NULL)
! 675: fatal("channel_register_expect: %d: bad id", id);
! 676:
! 677: cc = xmalloc(sizeof(*cc));
! 678: cc->cb = cb;
! 679: cc->abandon_cb = abandon_cb;
! 680: cc->ctx = ctx;
! 681: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
! 682: }
! 683:
! 684: void
! 685: channel_register_open_confirm(int id, channel_callback_fn *fn, void *ctx)
1.121 markus 686: {
687: Channel *c = channel_lookup(id);
1.180 deraadt 688:
1.121 markus 689: if (c == NULL) {
1.275 ! djm 690: logit("channel_register_open_comfirm: %d: bad id", id);
1.121 markus 691: return;
692: }
1.275 ! djm 693: c->open_confirm = fn;
! 694: c->open_confirm_ctx = ctx;
1.121 markus 695: }
1.241 deraadt 696:
1.121 markus 697: void
1.225 djm 698: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 699: {
1.229 markus 700: Channel *c = channel_by_id(id);
1.180 deraadt 701:
1.121 markus 702: if (c == NULL) {
1.188 itojun 703: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 704: return;
705: }
1.131 markus 706: c->detach_user = fn;
1.225 djm 707: c->detach_close = do_close;
1.121 markus 708: }
1.241 deraadt 709:
1.121 markus 710: void
711: channel_cancel_cleanup(int id)
712: {
1.229 markus 713: Channel *c = channel_by_id(id);
1.180 deraadt 714:
1.121 markus 715: if (c == NULL) {
1.188 itojun 716: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 717: return;
1.52 markus 718: }
1.131 markus 719: c->detach_user = NULL;
1.225 djm 720: c->detach_close = 0;
1.121 markus 721: }
1.241 deraadt 722:
1.121 markus 723: void
1.231 reyk 724: channel_register_filter(int id, channel_infilter_fn *ifn,
725: channel_outfilter_fn *ofn)
1.121 markus 726: {
727: Channel *c = channel_lookup(id);
1.180 deraadt 728:
1.121 markus 729: if (c == NULL) {
1.188 itojun 730: logit("channel_register_filter: %d: bad id", id);
1.121 markus 731: return;
1.52 markus 732: }
1.231 reyk 733: c->input_filter = ifn;
734: c->output_filter = ofn;
1.52 markus 735: }
736:
1.49 markus 737: void
1.121 markus 738: channel_set_fds(int id, int rfd, int wfd, int efd,
1.168 markus 739: int extusage, int nonblock, u_int window_max)
1.1 deraadt 740: {
1.121 markus 741: Channel *c = channel_lookup(id);
1.180 deraadt 742:
1.121 markus 743: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
744: fatal("channel_activate for non-larval channel %d.", id);
745: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
746: c->type = SSH_CHANNEL_OPEN;
1.168 markus 747: c->local_window = c->local_window_max = window_max;
1.121 markus 748: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
749: packet_put_int(c->remote_id);
750: packet_put_int(c->local_window);
751: packet_send();
1.1 deraadt 752: }
753:
1.27 markus 754: /*
1.41 markus 755: * 'channel_pre*' are called just before select() to add any bits relevant to
756: * channels in the select bitmasks.
757: */
758: /*
759: * 'channel_post*': perform any appropriate operations for channels which
760: * have events pending.
1.27 markus 761: */
1.237 deraadt 762: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 763: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
764: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
765:
1.259 stevesk 766: /* ARGSUSED */
1.127 itojun 767: static void
1.237 deraadt 768: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 769: {
770: FD_SET(c->sock, readset);
771: }
772:
1.259 stevesk 773: /* ARGSUSED */
1.127 itojun 774: static void
1.237 deraadt 775: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 776: {
777: debug3("channel %d: waiting for connection", c->self);
778: FD_SET(c->sock, writeset);
779: }
780:
1.127 itojun 781: static void
1.237 deraadt 782: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 783: {
784: if (buffer_len(&c->input) < packet_get_maxsize())
785: FD_SET(c->sock, readset);
786: if (buffer_len(&c->output) > 0)
787: FD_SET(c->sock, writeset);
788: }
1.1 deraadt 789:
1.127 itojun 790: static void
1.237 deraadt 791: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 792: {
1.157 markus 793: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 794:
1.44 markus 795: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 796: limit > 0 &&
1.250 djm 797: buffer_len(&c->input) < limit &&
798: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 799: FD_SET(c->rfd, readset);
800: if (c->ostate == CHAN_OUTPUT_OPEN ||
801: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
802: if (buffer_len(&c->output) > 0) {
803: FD_SET(c->wfd, writeset);
804: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 805: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 806: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
807: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 808: else
809: chan_obuf_empty(c);
1.44 markus 810: }
811: }
812: /** XXX check close conditions, too */
1.157 markus 813: if (compat20 && c->efd != -1) {
1.44 markus 814: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
815: buffer_len(&c->extended) > 0)
816: FD_SET(c->efd, writeset);
1.172 markus 817: else if (!(c->flags & CHAN_EOF_SENT) &&
818: c->extended_usage == CHAN_EXTENDED_READ &&
1.44 markus 819: buffer_len(&c->extended) < c->remote_window)
820: FD_SET(c->efd, readset);
821: }
1.204 djm 822: /* XXX: What about efd? races? */
1.208 deraadt 823: if (compat20 && c->ctl_fd != -1 &&
1.204 djm 824: c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
825: FD_SET(c->ctl_fd, readset);
1.44 markus 826: }
827:
1.259 stevesk 828: /* ARGSUSED */
1.127 itojun 829: static void
1.237 deraadt 830: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 831: {
832: if (buffer_len(&c->input) == 0) {
833: packet_start(SSH_MSG_CHANNEL_CLOSE);
834: packet_put_int(c->remote_id);
835: packet_send();
836: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 837: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 838: }
839: }
840:
1.259 stevesk 841: /* ARGSUSED */
1.127 itojun 842: static void
1.237 deraadt 843: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 844: {
845: if (buffer_len(&c->output) == 0)
1.113 markus 846: chan_mark_dead(c);
1.49 markus 847: else
1.41 markus 848: FD_SET(c->sock, writeset);
849: }
850:
851: /*
852: * This is a special state for X11 authentication spoofing. An opened X11
853: * connection (when authentication spoofing is being done) remains in this
854: * state until the first packet has been completely read. The authentication
855: * data in that packet is then substituted by the real data if it matches the
856: * fake data, and the channel is put into normal mode.
1.51 markus 857: * XXX All this happens at the client side.
1.121 markus 858: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 859: */
1.127 itojun 860: static int
1.121 markus 861: x11_open_helper(Buffer *b)
1.1 deraadt 862: {
1.77 markus 863: u_char *ucp;
864: u_int proto_len, data_len;
1.25 markus 865:
1.41 markus 866: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 867: if (buffer_len(b) < 12)
1.41 markus 868: return 0;
869:
870: /* Parse the lengths of variable-length fields. */
1.155 stevesk 871: ucp = buffer_ptr(b);
1.41 markus 872: if (ucp[0] == 0x42) { /* Byte order MSB first. */
873: proto_len = 256 * ucp[6] + ucp[7];
874: data_len = 256 * ucp[8] + ucp[9];
875: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
876: proto_len = ucp[6] + 256 * ucp[7];
877: data_len = ucp[8] + 256 * ucp[9];
878: } else {
1.194 markus 879: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 880: ucp[0]);
1.41 markus 881: return -1;
882: }
883:
884: /* Check if the whole packet is in buffer. */
1.121 markus 885: if (buffer_len(b) <
1.41 markus 886: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
887: return 0;
888:
889: /* Check if authentication protocol matches. */
890: if (proto_len != strlen(x11_saved_proto) ||
891: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 892: debug2("X11 connection uses different authentication protocol.");
1.41 markus 893: return -1;
894: }
895: /* Check if authentication data matches our fake data. */
896: if (data_len != x11_fake_data_len ||
897: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
898: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 899: debug2("X11 auth data does not match fake data.");
1.41 markus 900: return -1;
901: }
902: /* Check fake data length */
903: if (x11_fake_data_len != x11_saved_data_len) {
904: error("X11 fake_data_len %d != saved_data_len %d",
905: x11_fake_data_len, x11_saved_data_len);
906: return -1;
907: }
908: /*
909: * Received authentication protocol and data match
910: * our fake data. Substitute the fake data with real
911: * data.
912: */
913: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
914: x11_saved_data, x11_saved_data_len);
915: return 1;
916: }
917:
1.127 itojun 918: static void
1.237 deraadt 919: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 920: {
1.121 markus 921: int ret = x11_open_helper(&c->output);
1.180 deraadt 922:
1.41 markus 923: if (ret == 1) {
924: /* Start normal processing for the channel. */
925: c->type = SSH_CHANNEL_OPEN;
1.47 markus 926: channel_pre_open_13(c, readset, writeset);
1.41 markus 927: } else if (ret == -1) {
928: /*
929: * We have received an X11 connection that has bad
930: * authentication information.
931: */
1.188 itojun 932: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 933: buffer_clear(&c->input);
934: buffer_clear(&c->output);
1.132 markus 935: channel_close_fd(&c->sock);
1.41 markus 936: c->sock = -1;
937: c->type = SSH_CHANNEL_CLOSED;
938: packet_start(SSH_MSG_CHANNEL_CLOSE);
939: packet_put_int(c->remote_id);
940: packet_send();
941: }
942: }
1.25 markus 943:
1.127 itojun 944: static void
1.237 deraadt 945: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 946: {
1.121 markus 947: int ret = x11_open_helper(&c->output);
1.133 markus 948:
949: /* c->force_drain = 1; */
950:
1.41 markus 951: if (ret == 1) {
952: c->type = SSH_CHANNEL_OPEN;
1.157 markus 953: channel_pre_open(c, readset, writeset);
1.41 markus 954: } else if (ret == -1) {
1.188 itojun 955: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 956: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 957: chan_read_failed(c);
958: buffer_clear(&c->input);
959: chan_ibuf_empty(c);
960: buffer_clear(&c->output);
961: /* for proto v1, the peer will send an IEOF */
962: if (compat20)
963: chan_write_failed(c);
964: else
965: c->type = SSH_CHANNEL_OPEN;
1.194 markus 966: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 967: }
968: }
1.25 markus 969:
1.104 markus 970: /* try to decode a socks4 header */
1.259 stevesk 971: /* ARGSUSED */
1.127 itojun 972: static int
1.237 deraadt 973: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 974: {
1.181 markus 975: char *p, *host;
1.217 djm 976: u_int len, have, i, found;
1.148 deraadt 977: char username[256];
1.103 markus 978: struct {
979: u_int8_t version;
980: u_int8_t command;
981: u_int16_t dest_port;
1.104 markus 982: struct in_addr dest_addr;
1.103 markus 983: } s4_req, s4_rsp;
984:
1.104 markus 985: debug2("channel %d: decode socks4", c->self);
1.109 markus 986:
987: have = buffer_len(&c->input);
988: len = sizeof(s4_req);
989: if (have < len)
990: return 0;
991: p = buffer_ptr(&c->input);
992: for (found = 0, i = len; i < have; i++) {
993: if (p[i] == '\0') {
994: found = 1;
995: break;
996: }
997: if (i > 1024) {
998: /* the peer is probably sending garbage */
999: debug("channel %d: decode socks4: too long",
1000: c->self);
1001: return -1;
1002: }
1003: }
1004: if (!found)
1005: return 0;
1.103 markus 1006: buffer_get(&c->input, (char *)&s4_req.version, 1);
1007: buffer_get(&c->input, (char *)&s4_req.command, 1);
1008: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1009: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1010: have = buffer_len(&c->input);
1.103 markus 1011: p = buffer_ptr(&c->input);
1012: len = strlen(p);
1.106 markus 1013: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 1014: if (len > have)
1.104 markus 1015: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1016: c->self, len, have);
1017: strlcpy(username, p, sizeof(username));
1018: buffer_consume(&c->input, len);
1019: buffer_consume(&c->input, 1); /* trailing '\0' */
1020:
1.104 markus 1021: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 1022: strlcpy(c->path, host, sizeof(c->path));
1023: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1024:
1.194 markus 1025: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.106 markus 1026: c->self, host, c->host_port, s4_req.command);
1.103 markus 1027:
1.104 markus 1028: if (s4_req.command != 1) {
1029: debug("channel %d: cannot handle: socks4 cn %d",
1030: c->self, s4_req.command);
1031: return -1;
1.103 markus 1032: }
1.104 markus 1033: s4_rsp.version = 0; /* vn: 0 for reply */
1034: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1035: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1036: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1037: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1038: return 1;
1039: }
1040:
1.193 markus 1041: /* try to decode a socks5 header */
1042: #define SSH_SOCKS5_AUTHDONE 0x1000
1043: #define SSH_SOCKS5_NOAUTH 0x00
1044: #define SSH_SOCKS5_IPV4 0x01
1045: #define SSH_SOCKS5_DOMAIN 0x03
1046: #define SSH_SOCKS5_IPV6 0x04
1047: #define SSH_SOCKS5_CONNECT 0x01
1048: #define SSH_SOCKS5_SUCCESS 0x00
1049:
1.259 stevesk 1050: /* ARGSUSED */
1.193 markus 1051: static int
1.237 deraadt 1052: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1053: {
1054: struct {
1055: u_int8_t version;
1056: u_int8_t command;
1057: u_int8_t reserved;
1058: u_int8_t atyp;
1059: } s5_req, s5_rsp;
1060: u_int16_t dest_port;
1061: u_char *p, dest_addr[255+1];
1.252 djm 1062: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1063:
1064: debug2("channel %d: decode socks5", c->self);
1065: p = buffer_ptr(&c->input);
1066: if (p[0] != 0x05)
1067: return -1;
1068: have = buffer_len(&c->input);
1069: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1070: /* format: ver | nmethods | methods */
1.198 djm 1071: if (have < 2)
1.193 markus 1072: return 0;
1073: nmethods = p[1];
1074: if (have < nmethods + 2)
1075: return 0;
1076: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1077: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1078: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1079: found = 1;
1080: break;
1081: }
1082: }
1083: if (!found) {
1084: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1085: c->self);
1086: return -1;
1087: }
1088: buffer_consume(&c->input, nmethods + 2);
1089: buffer_put_char(&c->output, 0x05); /* version */
1090: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1091: FD_SET(c->sock, writeset);
1092: c->flags |= SSH_SOCKS5_AUTHDONE;
1093: debug2("channel %d: socks5 auth done", c->self);
1094: return 0; /* need more */
1095: }
1096: debug2("channel %d: socks5 post auth", c->self);
1097: if (have < sizeof(s5_req)+1)
1098: return 0; /* need more */
1.247 deraadt 1099: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1100: if (s5_req.version != 0x05 ||
1101: s5_req.command != SSH_SOCKS5_CONNECT ||
1102: s5_req.reserved != 0x00) {
1.194 markus 1103: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1104: return -1;
1105: }
1.213 deraadt 1106: switch (s5_req.atyp){
1.193 markus 1107: case SSH_SOCKS5_IPV4:
1108: addrlen = 4;
1109: af = AF_INET;
1110: break;
1111: case SSH_SOCKS5_DOMAIN:
1112: addrlen = p[sizeof(s5_req)];
1113: af = -1;
1114: break;
1115: case SSH_SOCKS5_IPV6:
1116: addrlen = 16;
1117: af = AF_INET6;
1118: break;
1119: default:
1.194 markus 1120: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1121: return -1;
1122: }
1.252 djm 1123: need = sizeof(s5_req) + addrlen + 2;
1124: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1125: need++;
1126: if (have < need)
1.193 markus 1127: return 0;
1128: buffer_consume(&c->input, sizeof(s5_req));
1129: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1130: buffer_consume(&c->input, 1); /* host string length */
1131: buffer_get(&c->input, (char *)&dest_addr, addrlen);
1132: buffer_get(&c->input, (char *)&dest_port, 2);
1133: dest_addr[addrlen] = '\0';
1134: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1.201 deraadt 1135: strlcpy(c->path, (char *)dest_addr, sizeof(c->path));
1.193 markus 1136: else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL)
1137: return -1;
1138: c->host_port = ntohs(dest_port);
1.198 djm 1139:
1.194 markus 1140: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1141: c->self, c->path, c->host_port, s5_req.command);
1142:
1143: s5_rsp.version = 0x05;
1144: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1145: s5_rsp.reserved = 0; /* ignored */
1146: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1147: ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1148: dest_port = 0; /* ignored */
1149:
1.246 deraadt 1150: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1151: buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1152: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1153: return 1;
1154: }
1155:
1.104 markus 1156: /* dynamic port forwarding */
1.127 itojun 1157: static void
1.237 deraadt 1158: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1159: {
1160: u_char *p;
1.217 djm 1161: u_int have;
1162: int ret;
1.103 markus 1163:
1.104 markus 1164: have = buffer_len(&c->input);
1.137 markus 1165: c->delayed = 0;
1.104 markus 1166: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1167: /* buffer_dump(&c->input); */
1.104 markus 1168: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1169: if (have < 3) {
1.104 markus 1170: /* need more */
1171: FD_SET(c->sock, readset);
1172: return;
1173: }
1174: /* try to guess the protocol */
1175: p = buffer_ptr(&c->input);
1176: switch (p[0]) {
1177: case 0x04:
1178: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1179: break;
1180: case 0x05:
1181: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1182: break;
1183: default:
1184: ret = -1;
1185: break;
1186: }
1187: if (ret < 0) {
1.113 markus 1188: chan_mark_dead(c);
1.104 markus 1189: } else if (ret == 0) {
1190: debug2("channel %d: pre_dynamic: need more", c->self);
1191: /* need more */
1192: FD_SET(c->sock, readset);
1193: } else {
1194: /* switch to the next state */
1195: c->type = SSH_CHANNEL_OPENING;
1196: port_open_helper(c, "direct-tcpip");
1197: }
1.103 markus 1198: }
1199:
1.41 markus 1200: /* This is our fake X11 server socket. */
1.259 stevesk 1201: /* ARGSUSED */
1.127 itojun 1202: static void
1.237 deraadt 1203: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1204: {
1.113 markus 1205: Channel *nc;
1.41 markus 1206: struct sockaddr addr;
1.162 stevesk 1207: int newsock;
1.41 markus 1208: socklen_t addrlen;
1.85 markus 1209: char buf[16384], *remote_ipaddr;
1.51 markus 1210: int remote_port;
1.25 markus 1211:
1.41 markus 1212: if (FD_ISSET(c->sock, readset)) {
1213: debug("X11 connection requested.");
1214: addrlen = sizeof(addr);
1215: newsock = accept(c->sock, &addr, &addrlen);
1.149 markus 1216: if (c->single_connection) {
1.194 markus 1217: debug2("single_connection: closing X11 listener.");
1.149 markus 1218: channel_close_fd(&c->sock);
1219: chan_mark_dead(c);
1220: }
1.41 markus 1221: if (newsock < 0) {
1222: error("accept: %.100s", strerror(errno));
1223: return;
1224: }
1.162 stevesk 1225: set_nodelay(newsock);
1.85 markus 1226: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1227: remote_port = get_peer_port(newsock);
1.41 markus 1228: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1229: remote_ipaddr, remote_port);
1.51 markus 1230:
1.113 markus 1231: nc = channel_new("accepted x11 socket",
1.51 markus 1232: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1233: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1234: if (compat20) {
1235: packet_start(SSH2_MSG_CHANNEL_OPEN);
1236: packet_put_cstring("x11");
1.113 markus 1237: packet_put_int(nc->self);
1.149 markus 1238: packet_put_int(nc->local_window_max);
1239: packet_put_int(nc->local_maxpacket);
1.85 markus 1240: /* originator ipaddr and port */
1241: packet_put_cstring(remote_ipaddr);
1.57 markus 1242: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1243: debug2("ssh2 x11 bug compat mode");
1.57 markus 1244: } else {
1245: packet_put_int(remote_port);
1246: }
1.51 markus 1247: packet_send();
1248: } else {
1249: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1250: packet_put_int(nc->self);
1.121 markus 1251: if (packet_get_protocol_flags() &
1252: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1253: packet_put_cstring(buf);
1.51 markus 1254: packet_send();
1255: }
1.85 markus 1256: xfree(remote_ipaddr);
1.41 markus 1257: }
1258: }
1.25 markus 1259:
1.127 itojun 1260: static void
1.103 markus 1261: port_open_helper(Channel *c, char *rtype)
1262: {
1263: int direct;
1264: char buf[1024];
1265: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1266: int remote_port = get_peer_port(c->sock);
1.103 markus 1267:
1268: direct = (strcmp(rtype, "direct-tcpip") == 0);
1269:
1270: snprintf(buf, sizeof buf,
1271: "%s: listening port %d for %.100s port %d, "
1272: "connect from %.200s port %d",
1273: rtype, c->listening_port, c->path, c->host_port,
1274: remote_ipaddr, remote_port);
1275:
1276: xfree(c->remote_name);
1277: c->remote_name = xstrdup(buf);
1278:
1279: if (compat20) {
1280: packet_start(SSH2_MSG_CHANNEL_OPEN);
1281: packet_put_cstring(rtype);
1282: packet_put_int(c->self);
1283: packet_put_int(c->local_window_max);
1284: packet_put_int(c->local_maxpacket);
1285: if (direct) {
1286: /* target host, port */
1287: packet_put_cstring(c->path);
1288: packet_put_int(c->host_port);
1289: } else {
1290: /* listen address, port */
1291: packet_put_cstring(c->path);
1292: packet_put_int(c->listening_port);
1293: }
1294: /* originator host and port */
1295: packet_put_cstring(remote_ipaddr);
1.216 markus 1296: packet_put_int((u_int)remote_port);
1.103 markus 1297: packet_send();
1298: } else {
1299: packet_start(SSH_MSG_PORT_OPEN);
1300: packet_put_int(c->self);
1301: packet_put_cstring(c->path);
1302: packet_put_int(c->host_port);
1.121 markus 1303: if (packet_get_protocol_flags() &
1304: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1305: packet_put_cstring(c->remote_name);
1306: packet_send();
1307: }
1308: xfree(remote_ipaddr);
1309: }
1310:
1.226 djm 1311: static void
1312: channel_set_reuseaddr(int fd)
1313: {
1314: int on = 1;
1315:
1316: /*
1317: * Set socket options.
1318: * Allow local port reuse in TIME_WAIT.
1319: */
1320: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1321: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1322: }
1323:
1.41 markus 1324: /*
1325: * This socket is listening for connections to a forwarded TCP/IP port.
1326: */
1.259 stevesk 1327: /* ARGSUSED */
1.127 itojun 1328: static void
1.237 deraadt 1329: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1330: {
1.103 markus 1331: Channel *nc;
1.41 markus 1332: struct sockaddr addr;
1.113 markus 1333: int newsock, nextstate;
1.41 markus 1334: socklen_t addrlen;
1.103 markus 1335: char *rtype;
1.73 markus 1336:
1.41 markus 1337: if (FD_ISSET(c->sock, readset)) {
1338: debug("Connection to port %d forwarding "
1339: "to %.100s port %d requested.",
1340: c->listening_port, c->path, c->host_port);
1.103 markus 1341:
1.137 markus 1342: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1343: nextstate = SSH_CHANNEL_OPENING;
1344: rtype = "forwarded-tcpip";
1345: } else {
1346: if (c->host_port == 0) {
1347: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1348: rtype = "dynamic-tcpip";
1.137 markus 1349: } else {
1350: nextstate = SSH_CHANNEL_OPENING;
1351: rtype = "direct-tcpip";
1352: }
1353: }
1.103 markus 1354:
1.41 markus 1355: addrlen = sizeof(addr);
1356: newsock = accept(c->sock, &addr, &addrlen);
1357: if (newsock < 0) {
1358: error("accept: %.100s", strerror(errno));
1359: return;
1360: }
1.169 stevesk 1361: set_nodelay(newsock);
1.190 markus 1362: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1363: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1364: nc->listening_port = c->listening_port;
1365: nc->host_port = c->host_port;
1366: strlcpy(nc->path, c->path, sizeof(nc->path));
1367:
1.137 markus 1368: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1369: /*
1370: * do not call the channel_post handler until
1371: * this flag has been reset by a pre-handler.
1372: * otherwise the FD_ISSET calls might overflow
1373: */
1374: nc->delayed = 1;
1375: } else {
1.103 markus 1376: port_open_helper(nc, rtype);
1.137 markus 1377: }
1.41 markus 1378: }
1379: }
1.25 markus 1380:
1.41 markus 1381: /*
1382: * This is the authentication agent socket listening for connections from
1383: * clients.
1384: */
1.259 stevesk 1385: /* ARGSUSED */
1.127 itojun 1386: static void
1.237 deraadt 1387: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1388: {
1.113 markus 1389: Channel *nc;
1390: int newsock;
1.41 markus 1391: struct sockaddr addr;
1392: socklen_t addrlen;
1.25 markus 1393:
1.41 markus 1394: if (FD_ISSET(c->sock, readset)) {
1395: addrlen = sizeof(addr);
1396: newsock = accept(c->sock, &addr, &addrlen);
1397: if (newsock < 0) {
1398: error("accept from auth socket: %.100s", strerror(errno));
1399: return;
1400: }
1.113 markus 1401: nc = channel_new("accepted auth socket",
1.73 markus 1402: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1403: c->local_window_max, c->local_maxpacket,
1.190 markus 1404: 0, "accepted auth socket", 1);
1.73 markus 1405: if (compat20) {
1406: packet_start(SSH2_MSG_CHANNEL_OPEN);
1407: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1408: packet_put_int(nc->self);
1.73 markus 1409: packet_put_int(c->local_window_max);
1410: packet_put_int(c->local_maxpacket);
1411: } else {
1412: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1413: packet_put_int(nc->self);
1.73 markus 1414: }
1.41 markus 1415: packet_send();
1416: }
1417: }
1.25 markus 1418:
1.259 stevesk 1419: /* ARGSUSED */
1.127 itojun 1420: static void
1.237 deraadt 1421: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1422: {
1.114 markus 1423: int err = 0;
1.129 stevesk 1424: socklen_t sz = sizeof(err);
1.114 markus 1425:
1.75 markus 1426: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1427: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1428: err = errno;
1429: error("getsockopt SO_ERROR failed");
1430: }
1431: if (err == 0) {
1432: debug("channel %d: connected", c->self);
1433: c->type = SSH_CHANNEL_OPEN;
1434: if (compat20) {
1435: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1436: packet_put_int(c->remote_id);
1437: packet_put_int(c->self);
1438: packet_put_int(c->local_window);
1439: packet_put_int(c->local_maxpacket);
1440: } else {
1441: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1442: packet_put_int(c->remote_id);
1443: packet_put_int(c->self);
1444: }
1.75 markus 1445: } else {
1.114 markus 1446: debug("channel %d: not connected: %s",
1447: c->self, strerror(err));
1448: if (compat20) {
1449: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1450: packet_put_int(c->remote_id);
1451: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1452: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1453: packet_put_cstring(strerror(err));
1454: packet_put_cstring("");
1455: }
1.75 markus 1456: } else {
1.114 markus 1457: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1458: packet_put_int(c->remote_id);
1.75 markus 1459: }
1.114 markus 1460: chan_mark_dead(c);
1.75 markus 1461: }
1.114 markus 1462: packet_send();
1.75 markus 1463: }
1464: }
1465:
1.259 stevesk 1466: /* ARGSUSED */
1.127 itojun 1467: static int
1.237 deraadt 1468: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1469: {
1.214 markus 1470: char buf[CHAN_RBUF];
1.41 markus 1471: int len;
1.25 markus 1472:
1.118 markus 1473: if (c->rfd != -1 &&
1.41 markus 1474: FD_ISSET(c->rfd, readset)) {
1475: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1476: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1477: return 1;
1.41 markus 1478: if (len <= 0) {
1.194 markus 1479: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1480: c->self, c->rfd, len);
1.104 markus 1481: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1482: debug2("channel %d: not open", c->self);
1.113 markus 1483: chan_mark_dead(c);
1.103 markus 1484: return -1;
1.104 markus 1485: } else if (compat13) {
1.158 markus 1486: buffer_clear(&c->output);
1.41 markus 1487: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1488: debug2("channel %d: input draining.", c->self);
1.25 markus 1489: } else {
1.41 markus 1490: chan_read_failed(c);
1.25 markus 1491: }
1.41 markus 1492: return -1;
1493: }
1.143 deraadt 1494: if (c->input_filter != NULL) {
1.66 markus 1495: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1496: debug2("channel %d: filter stops", c->self);
1.65 markus 1497: chan_read_failed(c);
1498: }
1.228 reyk 1499: } else if (c->datagram) {
1500: buffer_put_string(&c->input, buf, len);
1.65 markus 1501: } else {
1502: buffer_append(&c->input, buf, len);
1503: }
1.41 markus 1504: }
1505: return 1;
1506: }
1.241 deraadt 1507:
1.259 stevesk 1508: /* ARGSUSED */
1.127 itojun 1509: static int
1.237 deraadt 1510: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1511: {
1.95 markus 1512: struct termios tio;
1.231 reyk 1513: u_char *data = NULL, *buf;
1.134 markus 1514: u_int dlen;
1.41 markus 1515: int len;
1.25 markus 1516:
1.41 markus 1517: /* Send buffered output data to the socket. */
1.118 markus 1518: if (c->wfd != -1 &&
1.41 markus 1519: FD_ISSET(c->wfd, writeset) &&
1520: buffer_len(&c->output) > 0) {
1.231 reyk 1521: if (c->output_filter != NULL) {
1522: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1523: debug2("channel %d: filter stops", c->self);
1.232 reyk 1524: if (c->type != SSH_CHANNEL_OPEN)
1525: chan_mark_dead(c);
1526: else
1527: chan_write_failed(c);
1528: return -1;
1.231 reyk 1529: }
1530: } else if (c->datagram) {
1531: buf = data = buffer_get_string(&c->output, &dlen);
1532: } else {
1533: buf = data = buffer_ptr(&c->output);
1534: dlen = buffer_len(&c->output);
1535: }
1536:
1.228 reyk 1537: if (c->datagram) {
1538: /* ignore truncated writes, datagrams might get lost */
1539: c->local_consumed += dlen + 4;
1.231 reyk 1540: len = write(c->wfd, buf, dlen);
1.228 reyk 1541: xfree(data);
1542: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1543: return 1;
1544: if (len <= 0) {
1545: if (c->type != SSH_CHANNEL_OPEN)
1546: chan_mark_dead(c);
1547: else
1548: chan_write_failed(c);
1549: return -1;
1550: }
1551: return 1;
1552: }
1.231 reyk 1553:
1554: len = write(c->wfd, buf, dlen);
1.53 markus 1555: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1556: return 1;
1.41 markus 1557: if (len <= 0) {
1.104 markus 1558: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1559: debug2("channel %d: not open", c->self);
1.113 markus 1560: chan_mark_dead(c);
1.104 markus 1561: return -1;
1562: } else if (compat13) {
1.158 markus 1563: buffer_clear(&c->output);
1.194 markus 1564: debug2("channel %d: input draining.", c->self);
1.41 markus 1565: c->type = SSH_CHANNEL_INPUT_DRAINING;
1566: } else {
1567: chan_write_failed(c);
1568: }
1569: return -1;
1.91 markus 1570: }
1.231 reyk 1571: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1572: if (tcgetattr(c->wfd, &tio) == 0 &&
1573: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1574: /*
1575: * Simulate echo to reduce the impact of
1.96 markus 1576: * traffic analysis. We need to match the
1.95 markus 1577: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1578: * (4 byte channel id + buf)
1.91 markus 1579: */
1.95 markus 1580: packet_send_ignore(4 + len);
1.91 markus 1581: packet_send();
1582: }
1.25 markus 1583: }
1.41 markus 1584: buffer_consume(&c->output, len);
1.44 markus 1585: if (compat20 && len > 0) {
1586: c->local_consumed += len;
1587: }
1588: }
1589: return 1;
1590: }
1.241 deraadt 1591:
1.127 itojun 1592: static int
1.237 deraadt 1593: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1594: {
1.214 markus 1595: char buf[CHAN_RBUF];
1.44 markus 1596: int len;
1597:
1.45 markus 1598: /** XXX handle drain efd, too */
1.44 markus 1599: if (c->efd != -1) {
1600: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1601: FD_ISSET(c->efd, writeset) &&
1602: buffer_len(&c->extended) > 0) {
1603: len = write(c->efd, buffer_ptr(&c->extended),
1604: buffer_len(&c->extended));
1.70 markus 1605: debug2("channel %d: written %d to efd %d",
1.44 markus 1606: c->self, len, c->efd);
1.93 markus 1607: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1608: return 1;
1609: if (len <= 0) {
1610: debug2("channel %d: closing write-efd %d",
1611: c->self, c->efd);
1.132 markus 1612: channel_close_fd(&c->efd);
1.93 markus 1613: } else {
1.44 markus 1614: buffer_consume(&c->extended, len);
1615: c->local_consumed += len;
1616: }
1617: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1618: FD_ISSET(c->efd, readset)) {
1619: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1620: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1621: c->self, len, c->efd);
1.93 markus 1622: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1623: return 1;
1624: if (len <= 0) {
1625: debug2("channel %d: closing read-efd %d",
1.45 markus 1626: c->self, c->efd);
1.132 markus 1627: channel_close_fd(&c->efd);
1.93 markus 1628: } else {
1.44 markus 1629: buffer_append(&c->extended, buf, len);
1.93 markus 1630: }
1.44 markus 1631: }
1632: }
1633: return 1;
1634: }
1.241 deraadt 1635:
1.259 stevesk 1636: /* ARGSUSED */
1.127 itojun 1637: static int
1.237 deraadt 1638: channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
1.204 djm 1639: {
1640: char buf[16];
1641: int len;
1642:
1643: /* Monitor control fd to detect if the slave client exits */
1644: if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1645: len = read(c->ctl_fd, buf, sizeof(buf));
1646: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1647: return 1;
1648: if (len <= 0) {
1649: debug2("channel %d: ctl read<=0", c->self);
1650: if (c->type != SSH_CHANNEL_OPEN) {
1651: debug2("channel %d: not open", c->self);
1652: chan_mark_dead(c);
1653: return -1;
1654: } else {
1655: chan_read_failed(c);
1656: chan_write_failed(c);
1657: }
1658: return -1;
1659: } else
1660: fatal("%s: unexpected data on ctl fd", __func__);
1661: }
1662: return 1;
1663: }
1.241 deraadt 1664:
1.204 djm 1665: static int
1.93 markus 1666: channel_check_window(Channel *c)
1.44 markus 1667: {
1.104 markus 1668: if (c->type == SSH_CHANNEL_OPEN &&
1669: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1670: ((c->local_window_max - c->local_window >
1.269 markus 1671: c->local_maxpacket*3) ||
1672: c->local_window < c->local_window_max/2) &&
1.44 markus 1673: c->local_consumed > 0) {
1674: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1675: packet_put_int(c->remote_id);
1676: packet_put_int(c->local_consumed);
1677: packet_send();
1.70 markus 1678: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1679: c->self, c->local_window,
1680: c->local_consumed);
1681: c->local_window += c->local_consumed;
1682: c->local_consumed = 0;
1.1 deraadt 1683: }
1.41 markus 1684: return 1;
1.1 deraadt 1685: }
1686:
1.127 itojun 1687: static void
1.237 deraadt 1688: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1689: {
1.137 markus 1690: if (c->delayed)
1691: return;
1.41 markus 1692: channel_handle_rfd(c, readset, writeset);
1693: channel_handle_wfd(c, readset, writeset);
1.157 markus 1694: if (!compat20)
1.137 markus 1695: return;
1.44 markus 1696: channel_handle_efd(c, readset, writeset);
1.204 djm 1697: channel_handle_ctl(c, readset, writeset);
1.93 markus 1698: channel_check_window(c);
1.44 markus 1699: }
1700:
1.259 stevesk 1701: /* ARGSUSED */
1.127 itojun 1702: static void
1.237 deraadt 1703: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1704: {
1.41 markus 1705: int len;
1.180 deraadt 1706:
1.41 markus 1707: /* Send buffered output data to the socket. */
1708: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1709: len = write(c->sock, buffer_ptr(&c->output),
1710: buffer_len(&c->output));
1711: if (len <= 0)
1.158 markus 1712: buffer_clear(&c->output);
1.41 markus 1713: else
1714: buffer_consume(&c->output, len);
1715: }
1716: }
1.25 markus 1717:
1.127 itojun 1718: static void
1.44 markus 1719: channel_handler_init_20(void)
1720: {
1.157 markus 1721: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1722: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1723: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1724: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1725: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1726: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1727: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1728: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1729:
1.157 markus 1730: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1731: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1732: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1733: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1734: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1735: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1736: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1737: }
1738:
1.127 itojun 1739: static void
1.41 markus 1740: channel_handler_init_13(void)
1741: {
1742: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1743: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1744: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1745: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1746: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1747: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1748: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1749: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1750: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1751:
1.157 markus 1752: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1753: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1754: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1755: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1756: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1757: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1758: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1759: }
1.25 markus 1760:
1.127 itojun 1761: static void
1.41 markus 1762: channel_handler_init_15(void)
1763: {
1.157 markus 1764: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1765: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1766: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1767: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1768: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1769: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1770: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1771:
1.41 markus 1772: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1773: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1774: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1775: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1776: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1777: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1778: }
1.27 markus 1779:
1.127 itojun 1780: static void
1.41 markus 1781: channel_handler_init(void)
1782: {
1783: int i;
1.180 deraadt 1784:
1.148 deraadt 1785: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1786: channel_pre[i] = NULL;
1787: channel_post[i] = NULL;
1788: }
1.44 markus 1789: if (compat20)
1790: channel_handler_init_20();
1791: else if (compat13)
1.41 markus 1792: channel_handler_init_13();
1793: else
1794: channel_handler_init_15();
1795: }
1.25 markus 1796:
1.140 markus 1797: /* gc dead channels */
1798: static void
1799: channel_garbage_collect(Channel *c)
1800: {
1801: if (c == NULL)
1802: return;
1803: if (c->detach_user != NULL) {
1.225 djm 1804: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1805: return;
1.194 markus 1806: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1807: c->detach_user(c->self, NULL);
1808: /* if we still have a callback */
1809: if (c->detach_user != NULL)
1810: return;
1.194 markus 1811: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1812: }
1813: if (!chan_is_dead(c, 1))
1814: return;
1.194 markus 1815: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1816: channel_free(c);
1817: }
1818:
1.127 itojun 1819: static void
1.237 deraadt 1820: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
1.41 markus 1821: {
1822: static int did_init = 0;
1.209 avsm 1823: u_int i;
1.41 markus 1824: Channel *c;
1.25 markus 1825:
1.41 markus 1826: if (!did_init) {
1827: channel_handler_init();
1828: did_init = 1;
1829: }
1830: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1831: c = channels[i];
1832: if (c == NULL)
1.41 markus 1833: continue;
1.118 markus 1834: if (ftab[c->type] != NULL)
1835: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1836: channel_garbage_collect(c);
1.1 deraadt 1837: }
1838: }
1839:
1.121 markus 1840: /*
1841: * Allocate/update select bitmasks and add any bits relevant to channels in
1842: * select bitmasks.
1843: */
1.49 markus 1844: void
1.100 markus 1845: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.209 avsm 1846: u_int *nallocp, int rekeying)
1.41 markus 1847: {
1.243 djm 1848: u_int n, sz, nfdset;
1.84 markus 1849:
1850: n = MAX(*maxfdp, channel_max_fd);
1851:
1.243 djm 1852: nfdset = howmany(n+1, NFDBITS);
1853: /* Explicitly test here, because xrealloc isn't always called */
1854: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1855: fatal("channel_prepare_select: max_fd (%d) is too large", n);
1856: sz = nfdset * sizeof(fd_mask);
1857:
1.132 markus 1858: /* perhaps check sz < nalloc/2 and shrink? */
1859: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 1860: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1861: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 1862: *nallocp = sz;
1.84 markus 1863: }
1.132 markus 1864: *maxfdp = n;
1.84 markus 1865: memset(*readsetp, 0, sz);
1866: memset(*writesetp, 0, sz);
1867:
1.100 markus 1868: if (!rekeying)
1869: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1870: }
1871:
1.121 markus 1872: /*
1873: * After select, perform any appropriate operations for channels which have
1874: * events pending.
1875: */
1.49 markus 1876: void
1.237 deraadt 1877: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 1878: {
1879: channel_handler(channel_post, readset, writeset);
1880: }
1881:
1.121 markus 1882:
1.84 markus 1883: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 1884: void
1.142 itojun 1885: channel_output_poll(void)
1.1 deraadt 1886: {
1.41 markus 1887: Channel *c;
1.209 avsm 1888: u_int i, len;
1.1 deraadt 1889:
1.25 markus 1890: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1891: c = channels[i];
1892: if (c == NULL)
1893: continue;
1.37 markus 1894:
1.121 markus 1895: /*
1896: * We are only interested in channels that can have buffered
1897: * incoming data.
1898: */
1.37 markus 1899: if (compat13) {
1.41 markus 1900: if (c->type != SSH_CHANNEL_OPEN &&
1901: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1902: continue;
1903: } else {
1.41 markus 1904: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1905: continue;
1906: }
1.46 markus 1907: if (compat20 &&
1908: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1909: /* XXX is this true? */
1.140 markus 1910: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1911: continue;
1912: }
1.25 markus 1913:
1914: /* Get the amount of buffered data for this channel. */
1.93 markus 1915: if ((c->istate == CHAN_INPUT_OPEN ||
1916: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1917: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 1918: if (c->datagram) {
1919: if (len > 0) {
1920: u_char *data;
1921: u_int dlen;
1922:
1923: data = buffer_get_string(&c->input,
1924: &dlen);
1925: packet_start(SSH2_MSG_CHANNEL_DATA);
1926: packet_put_int(c->remote_id);
1927: packet_put_string(data, dlen);
1928: packet_send();
1929: c->remote_window -= dlen + 4;
1930: xfree(data);
1931: }
1932: continue;
1933: }
1.121 markus 1934: /*
1935: * Send some data for the other side over the secure
1936: * connection.
1937: */
1.44 markus 1938: if (compat20) {
1939: if (len > c->remote_window)
1940: len = c->remote_window;
1941: if (len > c->remote_maxpacket)
1942: len = c->remote_maxpacket;
1.25 markus 1943: } else {
1.44 markus 1944: if (packet_is_interactive()) {
1945: if (len > 1024)
1946: len = 512;
1947: } else {
1948: /* Keep the packets at reasonable size. */
1949: if (len > packet_get_maxsize()/2)
1950: len = packet_get_maxsize()/2;
1951: }
1.25 markus 1952: }
1.41 markus 1953: if (len > 0) {
1.44 markus 1954: packet_start(compat20 ?
1955: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1956: packet_put_int(c->remote_id);
1957: packet_put_string(buffer_ptr(&c->input), len);
1958: packet_send();
1959: buffer_consume(&c->input, len);
1960: c->remote_window -= len;
1961: }
1962: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1963: if (compat13)
1964: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1965: /*
1966: * input-buffer is empty and read-socket shutdown:
1.172 markus 1967: * tell peer, that we will not send more data: send IEOF.
1968: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 1969: */
1.172 markus 1970: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 1971: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
1972: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 1973: else
1974: chan_ibuf_empty(c);
1.25 markus 1975: }
1.44 markus 1976: /* Send extended data, i.e. stderr */
1977: if (compat20 &&
1.172 markus 1978: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 1979: c->remote_window > 0 &&
1980: (len = buffer_len(&c->extended)) > 0 &&
1981: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 1982: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 1983: c->self, c->remote_window, buffer_len(&c->extended),
1984: c->extended_usage);
1.44 markus 1985: if (len > c->remote_window)
1986: len = c->remote_window;
1987: if (len > c->remote_maxpacket)
1988: len = c->remote_maxpacket;
1989: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1990: packet_put_int(c->remote_id);
1991: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1992: packet_put_string(buffer_ptr(&c->extended), len);
1993: packet_send();
1994: buffer_consume(&c->extended, len);
1995: c->remote_window -= len;
1.93 markus 1996: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1997: }
1.25 markus 1998: }
1.1 deraadt 1999: }
2000:
1.121 markus 2001:
2002: /* -- protocol input */
1.249 djm 2003:
2004: /* ARGSUSED */
1.49 markus 2005: void
1.154 markus 2006: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2007: {
1.37 markus 2008: int id;
1.25 markus 2009: char *data;
1.77 markus 2010: u_int data_len;
1.41 markus 2011: Channel *c;
1.25 markus 2012:
2013: /* Get the channel number and verify it. */
1.37 markus 2014: id = packet_get_int();
1.41 markus 2015: c = channel_lookup(id);
2016: if (c == NULL)
1.37 markus 2017: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2018:
2019: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2020: if (c->type != SSH_CHANNEL_OPEN &&
2021: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 2022: return;
2023:
1.25 markus 2024: /* Get the data. */
1.274 markus 2025: data = packet_get_string_ptr(&data_len);
1.200 markus 2026:
2027: /*
2028: * Ignore data for protocol > 1.3 if output end is no longer open.
2029: * For protocol 2 the sending side is reducing its window as it sends
2030: * data, so we must 'fake' consumption of the data in order to ensure
2031: * that window updates are sent back. Otherwise the connection might
2032: * deadlock.
2033: */
2034: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2035: if (compat20) {
2036: c->local_window -= data_len;
2037: c->local_consumed += data_len;
2038: }
2039: return;
2040: }
1.41 markus 2041:
1.143 deraadt 2042: if (compat20) {
1.44 markus 2043: if (data_len > c->local_maxpacket) {
1.188 itojun 2044: logit("channel %d: rcvd big packet %d, maxpack %d",
1.44 markus 2045: c->self, data_len, c->local_maxpacket);
2046: }
2047: if (data_len > c->local_window) {
1.188 itojun 2048: logit("channel %d: rcvd too much data %d, win %d",
1.44 markus 2049: c->self, data_len, c->local_window);
2050: return;
2051: }
2052: c->local_window -= data_len;
2053: }
1.228 reyk 2054: if (c->datagram)
2055: buffer_put_string(&c->output, data, data_len);
2056: else
2057: buffer_append(&c->output, data, data_len);
1.274 markus 2058: packet_check_eom();
1.1 deraadt 2059: }
1.121 markus 2060:
1.249 djm 2061: /* ARGSUSED */
1.49 markus 2062: void
1.154 markus 2063: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2064: {
2065: int id;
2066: char *data;
1.177 markus 2067: u_int data_len, tcode;
1.44 markus 2068: Channel *c;
2069:
2070: /* Get the channel number and verify it. */
2071: id = packet_get_int();
2072: c = channel_lookup(id);
2073:
2074: if (c == NULL)
2075: packet_disconnect("Received extended_data for bad channel %d.", id);
2076: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2077: logit("channel %d: ext data for non open", id);
1.44 markus 2078: return;
1.172 markus 2079: }
2080: if (c->flags & CHAN_EOF_RCVD) {
2081: if (datafellows & SSH_BUG_EXTEOF)
2082: debug("channel %d: accepting ext data after eof", id);
2083: else
2084: packet_disconnect("Received extended_data after EOF "
2085: "on channel %d.", id);
1.44 markus 2086: }
2087: tcode = packet_get_int();
2088: if (c->efd == -1 ||
2089: c->extended_usage != CHAN_EXTENDED_WRITE ||
2090: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2091: logit("channel %d: bad ext data", c->self);
1.44 markus 2092: return;
2093: }
2094: data = packet_get_string(&data_len);
1.152 markus 2095: packet_check_eom();
1.44 markus 2096: if (data_len > c->local_window) {
1.188 itojun 2097: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2098: c->self, data_len, c->local_window);
2099: xfree(data);
2100: return;
2101: }
1.70 markus 2102: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2103: c->local_window -= data_len;
2104: buffer_append(&c->extended, data, data_len);
2105: xfree(data);
2106: }
2107:
1.249 djm 2108: /* ARGSUSED */
1.49 markus 2109: void
1.154 markus 2110: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2111: {
2112: int id;
2113: Channel *c;
2114:
2115: id = packet_get_int();
1.152 markus 2116: packet_check_eom();
1.41 markus 2117: c = channel_lookup(id);
2118: if (c == NULL)
2119: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2120: chan_rcvd_ieof(c);
1.133 markus 2121:
2122: /* XXX force input close */
1.156 markus 2123: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2124: debug("channel %d: FORCE input drain", c->self);
2125: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2126: if (buffer_len(&c->input) == 0)
2127: chan_ibuf_empty(c);
1.133 markus 2128: }
2129:
1.41 markus 2130: }
1.1 deraadt 2131:
1.249 djm 2132: /* ARGSUSED */
1.49 markus 2133: void
1.154 markus 2134: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2135: {
1.41 markus 2136: int id;
2137: Channel *c;
1.1 deraadt 2138:
1.41 markus 2139: id = packet_get_int();
1.152 markus 2140: packet_check_eom();
1.41 markus 2141: c = channel_lookup(id);
2142: if (c == NULL)
2143: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2144:
2145: /*
2146: * Send a confirmation that we have closed the channel and no more
2147: * data is coming for it.
2148: */
1.25 markus 2149: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2150: packet_put_int(c->remote_id);
1.25 markus 2151: packet_send();
2152:
1.27 markus 2153: /*
2154: * If the channel is in closed state, we have sent a close request,
2155: * and the other side will eventually respond with a confirmation.
2156: * Thus, we cannot free the channel here, because then there would be
2157: * no-one to receive the confirmation. The channel gets freed when
2158: * the confirmation arrives.
2159: */
1.41 markus 2160: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2161: /*
2162: * Not a closed channel - mark it as draining, which will
2163: * cause it to be freed later.
2164: */
1.158 markus 2165: buffer_clear(&c->input);
1.41 markus 2166: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2167: }
1.1 deraadt 2168: }
2169:
1.41 markus 2170: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2171: /* ARGSUSED */
1.49 markus 2172: void
1.154 markus 2173: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2174: {
2175: int id = packet_get_int();
2176: Channel *c = channel_lookup(id);
1.151 markus 2177:
1.152 markus 2178: packet_check_eom();
1.41 markus 2179: if (c == NULL)
2180: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2181: chan_rcvd_oclose(c);
2182: }
1.1 deraadt 2183:
1.249 djm 2184: /* ARGSUSED */
1.49 markus 2185: void
1.154 markus 2186: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2187: {
1.41 markus 2188: int id = packet_get_int();
2189: Channel *c = channel_lookup(id);
1.1 deraadt 2190:
1.152 markus 2191: packet_check_eom();
1.41 markus 2192: if (c == NULL)
2193: packet_disconnect("Received close confirmation for "
2194: "out-of-range channel %d.", id);
2195: if (c->type != SSH_CHANNEL_CLOSED)
2196: packet_disconnect("Received close confirmation for "
2197: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2198: channel_free(c);
1.1 deraadt 2199: }
2200:
1.249 djm 2201: /* ARGSUSED */
1.49 markus 2202: void
1.154 markus 2203: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2204: {
1.41 markus 2205: int id, remote_id;
2206: Channel *c;
1.1 deraadt 2207:
1.41 markus 2208: id = packet_get_int();
2209: c = channel_lookup(id);
1.25 markus 2210:
1.41 markus 2211: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2212: packet_disconnect("Received open confirmation for "
2213: "non-opening channel %d.", id);
2214: remote_id = packet_get_int();
1.27 markus 2215: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2216: c->remote_id = remote_id;
2217: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2218:
2219: if (compat20) {
2220: c->remote_window = packet_get_int();
2221: c->remote_maxpacket = packet_get_int();
1.275 ! djm 2222: if (c->open_confirm) {
1.70 markus 2223: debug2("callback start");
1.275 ! djm 2224: c->open_confirm(c->self, c->open_confirm_ctx);
1.70 markus 2225: debug2("callback done");
1.44 markus 2226: }
1.194 markus 2227: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2228: c->remote_window, c->remote_maxpacket);
2229: }
1.152 markus 2230: packet_check_eom();
1.1 deraadt 2231: }
2232:
1.127 itojun 2233: static char *
1.114 markus 2234: reason2txt(int reason)
2235: {
1.143 deraadt 2236: switch (reason) {
1.114 markus 2237: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2238: return "administratively prohibited";
2239: case SSH2_OPEN_CONNECT_FAILED:
2240: return "connect failed";
2241: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2242: return "unknown channel type";
2243: case SSH2_OPEN_RESOURCE_SHORTAGE:
2244: return "resource shortage";
2245: }
1.117 stevesk 2246: return "unknown reason";
1.114 markus 2247: }
2248:
1.249 djm 2249: /* ARGSUSED */
1.49 markus 2250: void
1.154 markus 2251: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2252: {
1.86 markus 2253: int id, reason;
2254: char *msg = NULL, *lang = NULL;
1.41 markus 2255: Channel *c;
2256:
2257: id = packet_get_int();
2258: c = channel_lookup(id);
1.25 markus 2259:
1.41 markus 2260: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2261: packet_disconnect("Received open failure for "
2262: "non-opening channel %d.", id);
1.44 markus 2263: if (compat20) {
1.86 markus 2264: reason = packet_get_int();
1.110 markus 2265: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2266: msg = packet_get_string(NULL);
2267: lang = packet_get_string(NULL);
2268: }
1.188 itojun 2269: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2270: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 2271: if (msg != NULL)
2272: xfree(msg);
2273: if (lang != NULL)
2274: xfree(lang);
1.44 markus 2275: }
1.152 markus 2276: packet_check_eom();
1.25 markus 2277: /* Free the channel. This will also close the socket. */
1.113 markus 2278: channel_free(c);
1.44 markus 2279: }
2280:
1.249 djm 2281: /* ARGSUSED */
1.121 markus 2282: void
1.154 markus 2283: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2284: {
2285: Channel *c;
1.178 markus 2286: int id;
2287: u_int adjust;
1.121 markus 2288:
2289: if (!compat20)
2290: return;
2291:
2292: /* Get the channel number and verify it. */
2293: id = packet_get_int();
2294: c = channel_lookup(id);
1.1 deraadt 2295:
1.229 markus 2296: if (c == NULL) {
2297: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2298: return;
2299: }
2300: adjust = packet_get_int();
1.152 markus 2301: packet_check_eom();
1.178 markus 2302: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2303: c->remote_window += adjust;
2304: }
1.1 deraadt 2305:
1.249 djm 2306: /* ARGSUSED */
1.121 markus 2307: void
1.154 markus 2308: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2309: {
1.121 markus 2310: Channel *c = NULL;
2311: u_short host_port;
2312: char *host, *originator_string;
2313: int remote_id, sock = -1;
2314:
2315: remote_id = packet_get_int();
2316: host = packet_get_string(NULL);
2317: host_port = packet_get_int();
1.25 markus 2318:
1.121 markus 2319: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2320: originator_string = packet_get_string(NULL);
2321: } else {
2322: originator_string = xstrdup("unknown (remote did not supply name)");
2323: }
1.152 markus 2324: packet_check_eom();
1.121 markus 2325: sock = channel_connect_to(host, host_port);
2326: if (sock != -1) {
2327: c = channel_new("connected socket",
2328: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2329: originator_string, 1);
1.167 markus 2330: c->remote_id = remote_id;
1.25 markus 2331: }
1.190 markus 2332: xfree(originator_string);
1.121 markus 2333: if (c == NULL) {
2334: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2335: packet_put_int(remote_id);
2336: packet_send();
2337: }
2338: xfree(host);
1.1 deraadt 2339: }
2340:
1.275 ! djm 2341: /* ARGSUSED */
! 2342: void
! 2343: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
! 2344: {
! 2345: Channel *c;
! 2346: struct channel_confirm *cc;
! 2347: int remote_id;
! 2348:
! 2349: /* Reset keepalive timeout */
! 2350: keep_alive_timeouts = 0;
! 2351:
! 2352: remote_id = packet_get_int();
! 2353: packet_check_eom();
! 2354:
! 2355: debug2("channel_input_confirm: type %d id %d", type, remote_id);
! 2356:
! 2357: if ((c = channel_lookup(remote_id)) == NULL) {
! 2358: logit("channel_input_success_failure: %d: unknown", remote_id);
! 2359: return;
! 2360: }
! 2361: ;
! 2362: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
! 2363: return;
! 2364: cc->cb(type, c, cc->ctx);
! 2365: TAILQ_REMOVE(&c->status_confirms, cc, entry);
! 2366: bzero(cc, sizeof(*cc));
! 2367: xfree(cc);
! 2368: }
1.121 markus 2369:
2370: /* -- tcp forwarding */
1.135 markus 2371:
2372: void
2373: channel_set_af(int af)
2374: {
2375: IPv4or6 = af;
2376: }
1.121 markus 2377:
1.160 markus 2378: static int
2379: channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port,
2380: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2381: {
1.113 markus 2382: Channel *c;
1.226 djm 2383: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2384: struct addrinfo hints, *ai, *aitop;
1.212 djm 2385: const char *host, *addr;
1.35 markus 2386: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.25 markus 2387:
1.160 markus 2388: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2389: listen_addr : host_to_connect;
1.212 djm 2390: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2391:
1.160 markus 2392: if (host == NULL) {
2393: error("No forward host name.");
1.218 markus 2394: return 0;
1.73 markus 2395: }
1.113 markus 2396: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2397: error("Forward host name too long.");
1.218 markus 2398: return 0;
1.87 markus 2399: }
1.25 markus 2400:
1.28 markus 2401: /*
1.212 djm 2402: * Determine whether or not a port forward listens to loopback,
1.213 deraadt 2403: * specified address or wildcard. On the client, a specified bind
2404: * address will always override gateway_ports. On the server, a
2405: * gateway_ports of 1 (``yes'') will override the client's
2406: * specification and force a wildcard bind, whereas a value of 2
2407: * (``clientspecified'') will bind to whatever address the client
1.212 djm 2408: * asked for.
2409: *
2410: * Special-case listen_addrs are:
2411: *
2412: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2413: * "" (empty string), "*" -> wildcard v4/v6
2414: * "localhost" -> loopback v4/v6
2415: */
2416: addr = NULL;
2417: if (listen_addr == NULL) {
2418: /* No address specified: default to gateway_ports setting */
2419: if (gateway_ports)
2420: wildcard = 1;
2421: } else if (gateway_ports || is_client) {
2422: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
1.272 djm 2423: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
1.212 djm 2424: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2425: (!is_client && gateway_ports == 1))
2426: wildcard = 1;
2427: else if (strcmp(listen_addr, "localhost") != 0)
2428: addr = listen_addr;
2429: }
2430:
2431: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2432: type, wildcard, (addr == NULL) ? "NULL" : addr);
2433:
2434: /*
1.35 markus 2435: * getaddrinfo returns a loopback address if the hostname is
2436: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2437: */
1.35 markus 2438: memset(&hints, 0, sizeof(hints));
2439: hints.ai_family = IPv4or6;
1.212 djm 2440: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2441: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2442: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2443: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2444: if (addr == NULL) {
2445: /* This really shouldn't happen */
2446: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2447: ssh_gai_strerror(r));
1.212 djm 2448: } else {
1.218 markus 2449: error("channel_setup_fwd_listener: "
1.271 dtucker 2450: "getaddrinfo(%.64s): %s", addr,
2451: ssh_gai_strerror(r));
1.212 djm 2452: }
1.218 markus 2453: return 0;
1.212 djm 2454: }
1.35 markus 2455:
2456: for (ai = aitop; ai; ai = ai->ai_next) {
2457: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2458: continue;
2459: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2460: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2461: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2462: continue;
2463: }
2464: /* Create a port to listen for the host. */
1.189 markus 2465: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2466: if (sock < 0) {
2467: /* this is no error since kernel may not support ipv6 */
2468: verbose("socket: %.100s", strerror(errno));
2469: continue;
2470: }
1.226 djm 2471:
2472: channel_set_reuseaddr(sock);
1.182 stevesk 2473:
1.35 markus 2474: debug("Local forwarding listening on %s port %s.", ntop, strport);
2475:
2476: /* Bind the socket to the address. */
2477: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2478: /* address can be in use ipv6 address is already bound */
2479: verbose("bind: %.100s", strerror(errno));
2480: close(sock);
2481: continue;
2482: }
2483: /* Start listening for connections on the socket. */
1.199 markus 2484: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2485: error("listen: %.100s", strerror(errno));
2486: close(sock);
2487: continue;
2488: }
2489: /* Allocate a channel number for the socket. */
1.121 markus 2490: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2491: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2492: 0, "port listener", 1);
1.113 markus 2493: strlcpy(c->path, host, sizeof(c->path));
2494: c->host_port = port_to_connect;
2495: c->listening_port = listen_port;
1.35 markus 2496: success = 1;
2497: }
2498: if (success == 0)
1.160 markus 2499: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2500: listen_port);
1.35 markus 2501: freeaddrinfo(aitop);
1.87 markus 2502: return success;
1.25 markus 2503: }
1.1 deraadt 2504:
1.202 djm 2505: int
2506: channel_cancel_rport_listener(const char *host, u_short port)
2507: {
1.209 avsm 2508: u_int i;
2509: int found = 0;
1.202 djm 2510:
1.213 deraadt 2511: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2512: Channel *c = channels[i];
2513:
2514: if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
2515: strncmp(c->path, host, sizeof(c->path)) == 0 &&
1.208 deraadt 2516: c->listening_port == port) {
1.210 djm 2517: debug2("%s: close channel %d", __func__, i);
1.202 djm 2518: channel_free(c);
2519: found = 1;
2520: }
2521: }
2522:
2523: return (found);
2524: }
2525:
1.160 markus 2526: /* protocol local port fwd, used by ssh (and sshd in v1) */
2527: int
1.212 djm 2528: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2529: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2530: {
2531: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.212 djm 2532: listen_host, listen_port, host_to_connect, port_to_connect,
2533: gateway_ports);
1.160 markus 2534: }
2535:
2536: /* protocol v2 remote port fwd, used by sshd */
2537: int
2538: channel_setup_remote_fwd_listener(const char *listen_address,
2539: u_short listen_port, int gateway_ports)
2540: {
2541: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
2542: listen_address, listen_port, NULL, 0, gateway_ports);
2543: }
2544:
1.27 markus 2545: /*
2546: * Initiate forwarding of connections to port "port" on remote host through
2547: * the secure channel to host:port from local side.
2548: */
1.1 deraadt 2549:
1.253 markus 2550: int
1.212 djm 2551: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2552: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2553: {
1.153 markus 2554: int type, success = 0;
1.73 markus 2555:
1.25 markus 2556: /* Record locally that connection to this host/port is permitted. */
2557: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2558: fatal("channel_request_remote_forwarding: too many forwards");
2559:
2560: /* Send the forward request to the remote side. */
1.44 markus 2561: if (compat20) {
1.212 djm 2562: const char *address_to_bind;
1.267 djm 2563: if (listen_host == NULL) {
2564: if (datafellows & SSH_BUG_RFWD_ADDR)
2565: address_to_bind = "127.0.0.1";
2566: else
2567: address_to_bind = "localhost";
2568: } else if (*listen_host == '\0' ||
2569: strcmp(listen_host, "*") == 0) {
2570: if (datafellows & SSH_BUG_RFWD_ADDR)
2571: address_to_bind = "0.0.0.0";
2572: else
2573: address_to_bind = "";
2574: } else
1.212 djm 2575: address_to_bind = listen_host;
2576:
1.44 markus 2577: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2578: packet_put_cstring("tcpip-forward");
1.173 markus 2579: packet_put_char(1); /* boolean: want reply */
1.44 markus 2580: packet_put_cstring(address_to_bind);
2581: packet_put_int(listen_port);
1.73 markus 2582: packet_send();
2583: packet_write_wait();
2584: /* Assume that server accepts the request */
2585: success = 1;
1.44 markus 2586: } else {
2587: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2588: packet_put_int(listen_port);
2589: packet_put_cstring(host_to_connect);
1.44 markus 2590: packet_put_int(port_to_connect);
2591: packet_send();
2592: packet_write_wait();
1.73 markus 2593:
2594: /* Wait for response from the remote side. */
1.153 markus 2595: type = packet_read();
1.73 markus 2596: switch (type) {
2597: case SSH_SMSG_SUCCESS:
2598: success = 1;
2599: break;
2600: case SSH_SMSG_FAILURE:
2601: break;
2602: default:
2603: /* Unknown packet */
2604: packet_disconnect("Protocol error for port forward request:"
2605: "received packet type %d.", type);
2606: }
2607: }
2608: if (success) {
2609: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2610: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2611: permitted_opens[num_permitted_opens].listen_port = listen_port;
2612: num_permitted_opens++;
1.44 markus 2613: }
1.253 markus 2614: return (success ? 0 : -1);
1.1 deraadt 2615: }
2616:
1.27 markus 2617: /*
1.208 deraadt 2618: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 2619: * local side.
2620: */
2621: void
1.212 djm 2622: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 2623: {
2624: int i;
2625:
2626: if (!compat20)
2627: return;
2628:
2629: for (i = 0; i < num_permitted_opens; i++) {
1.208 deraadt 2630: if (permitted_opens[i].host_to_connect != NULL &&
1.202 djm 2631: permitted_opens[i].listen_port == port)
2632: break;
2633: }
2634: if (i >= num_permitted_opens) {
2635: debug("%s: requested forward not found", __func__);
2636: return;
2637: }
2638: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2639: packet_put_cstring("cancel-tcpip-forward");
2640: packet_put_char(0);
1.212 djm 2641: packet_put_cstring(host == NULL ? "" : host);
1.202 djm 2642: packet_put_int(port);
2643: packet_send();
2644:
2645: permitted_opens[i].listen_port = 0;
2646: permitted_opens[i].port_to_connect = 0;
1.227 stevesk 2647: xfree(permitted_opens[i].host_to_connect);
1.202 djm 2648: permitted_opens[i].host_to_connect = NULL;
2649: }
2650:
2651: /*
1.27 markus 2652: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2653: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 2654: * message if there was an error).
1.27 markus 2655: */
1.253 markus 2656: int
1.56 markus 2657: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2658: {
1.31 markus 2659: u_short port, host_port;
1.253 markus 2660: int success = 0;
1.25 markus 2661: char *hostname;
1.1 deraadt 2662:
1.25 markus 2663: /* Get arguments from the packet. */
2664: port = packet_get_int();
2665: hostname = packet_get_string(NULL);
2666: host_port = packet_get_int();
2667:
1.27 markus 2668: /*
2669: * Check that an unprivileged user is not trying to forward a
2670: * privileged port.
2671: */
1.25 markus 2672: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 2673: packet_disconnect(
2674: "Requested forwarding of port %d but user is not root.",
2675: port);
2676: if (host_port == 0)
2677: packet_disconnect("Dynamic forwarding denied.");
2678:
1.73 markus 2679: /* Initiate forwarding */
1.253 markus 2680: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 2681: host_port, gateway_ports);
1.25 markus 2682:
2683: /* Free the argument string. */
2684: xfree(hostname);
1.253 markus 2685:
2686: return (success ? 0 : -1);
1.1 deraadt 2687: }
2688:
1.99 markus 2689: /*
2690: * Permits opening to any host/port if permitted_opens[] is empty. This is
2691: * usually called by the server, because the user could connect to any port
2692: * anyway, and the server has no way to know but to trust the client anyway.
2693: */
2694: void
1.142 itojun 2695: channel_permit_all_opens(void)
1.99 markus 2696: {
2697: if (num_permitted_opens == 0)
2698: all_opens_permitted = 1;
2699: }
2700:
1.101 markus 2701: void
1.99 markus 2702: channel_add_permitted_opens(char *host, int port)
2703: {
2704: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1.253 markus 2705: fatal("channel_add_permitted_opens: too many forwards");
1.99 markus 2706: debug("allow port forwarding to host %s port %d", host, port);
2707:
2708: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2709: permitted_opens[num_permitted_opens].port_to_connect = port;
2710: num_permitted_opens++;
2711:
2712: all_opens_permitted = 0;
2713: }
2714:
1.258 dtucker 2715: int
1.257 dtucker 2716: channel_add_adm_permitted_opens(char *host, int port)
2717: {
2718: if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2719: fatal("channel_add_adm_permitted_opens: too many forwards");
1.258 dtucker 2720: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 2721:
2722: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
2723: = xstrdup(host);
2724: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.258 dtucker 2725: return ++num_adm_permitted_opens;
1.257 dtucker 2726: }
2727:
2728: void
1.99 markus 2729: channel_clear_permitted_opens(void)
2730: {
2731: int i;
2732:
2733: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2734: if (permitted_opens[i].host_to_connect != NULL)
2735: xfree(permitted_opens[i].host_to_connect);
1.99 markus 2736: num_permitted_opens = 0;
1.257 dtucker 2737: }
2738:
2739: void
2740: channel_clear_adm_permitted_opens(void)
2741: {
2742: int i;
1.99 markus 2743:
1.257 dtucker 2744: for (i = 0; i < num_adm_permitted_opens; i++)
2745: if (permitted_adm_opens[i].host_to_connect != NULL)
2746: xfree(permitted_adm_opens[i].host_to_connect);
2747: num_adm_permitted_opens = 0;
1.99 markus 2748: }
2749:
2750: /* return socket to remote host, port */
1.127 itojun 2751: static int
1.99 markus 2752: connect_to(const char *host, u_short port)
1.41 markus 2753: {
2754: struct addrinfo hints, *ai, *aitop;
2755: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2756: int gaierr;
2757: int sock = -1;
2758:
2759: memset(&hints, 0, sizeof(hints));
2760: hints.ai_family = IPv4or6;
2761: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2762: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2763: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2764: error("connect_to %.100s: unknown host (%s)", host,
1.271 dtucker 2765: ssh_gai_strerror(gaierr));
1.41 markus 2766: return -1;
2767: }
2768: for (ai = aitop; ai; ai = ai->ai_next) {
2769: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2770: continue;
2771: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2772: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2773: error("connect_to: getnameinfo failed");
1.41 markus 2774: continue;
2775: }
1.189 markus 2776: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.41 markus 2777: if (sock < 0) {
1.186 djm 2778: if (ai->ai_next == NULL)
2779: error("socket: %.100s", strerror(errno));
2780: else
2781: verbose("socket: %.100s", strerror(errno));
1.41 markus 2782: continue;
2783: }
1.205 djm 2784: if (set_nonblock(sock) == -1)
2785: fatal("%s: set_nonblock(%d)", __func__, sock);
1.75 markus 2786: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2787: errno != EINPROGRESS) {
1.99 markus 2788: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2789: strerror(errno));
2790: close(sock);
1.89 stevesk 2791: continue; /* fail -- try next */
1.41 markus 2792: }
2793: break; /* success */
2794:
2795: }
2796: freeaddrinfo(aitop);
2797: if (!ai) {
1.99 markus 2798: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2799: return -1;
2800: }
2801: /* success */
1.169 stevesk 2802: set_nodelay(sock);
1.41 markus 2803: return sock;
2804: }
1.99 markus 2805:
1.73 markus 2806: int
1.130 stevesk 2807: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2808: {
2809: int i;
1.99 markus 2810:
1.73 markus 2811: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2812: if (permitted_opens[i].host_to_connect != NULL &&
2813: permitted_opens[i].listen_port == listen_port)
1.99 markus 2814: return connect_to(
1.73 markus 2815: permitted_opens[i].host_to_connect,
2816: permitted_opens[i].port_to_connect);
1.74 markus 2817: error("WARNING: Server requests forwarding for unknown listen_port %d",
2818: listen_port);
1.73 markus 2819: return -1;
2820: }
2821:
1.99 markus 2822: /* Check if connecting to that port is permitted and connect. */
2823: int
2824: channel_connect_to(const char *host, u_short port)
2825: {
1.257 dtucker 2826: int i, permit, permit_adm = 1;
1.99 markus 2827:
2828: permit = all_opens_permitted;
2829: if (!permit) {
2830: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2831: if (permitted_opens[i].host_to_connect != NULL &&
2832: permitted_opens[i].port_to_connect == port &&
1.99 markus 2833: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2834: permit = 1;
1.257 dtucker 2835: }
1.99 markus 2836:
1.257 dtucker 2837: if (num_adm_permitted_opens > 0) {
2838: permit_adm = 0;
2839: for (i = 0; i < num_adm_permitted_opens; i++)
2840: if (permitted_adm_opens[i].host_to_connect != NULL &&
2841: permitted_adm_opens[i].port_to_connect == port &&
2842: strcmp(permitted_adm_opens[i].host_to_connect, host)
2843: == 0)
2844: permit_adm = 1;
1.99 markus 2845: }
1.257 dtucker 2846:
2847: if (!permit || !permit_adm) {
1.188 itojun 2848: logit("Received request to connect to host %.100s port %d, "
1.99 markus 2849: "but the request was denied.", host, port);
2850: return -1;
2851: }
2852: return connect_to(host, port);
1.204 djm 2853: }
2854:
2855: void
2856: channel_send_window_changes(void)
2857: {
1.209 avsm 2858: u_int i;
1.204 djm 2859: struct winsize ws;
2860:
2861: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 2862: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 2863: channels[i]->type != SSH_CHANNEL_OPEN)
2864: continue;
2865: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
2866: continue;
2867: channel_request_start(i, "window-change", 0);
1.238 deraadt 2868: packet_put_int((u_int)ws.ws_col);
2869: packet_put_int((u_int)ws.ws_row);
2870: packet_put_int((u_int)ws.ws_xpixel);
2871: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 2872: packet_send();
2873: }
1.99 markus 2874: }
2875:
1.121 markus 2876: /* -- X11 forwarding */
1.1 deraadt 2877:
1.27 markus 2878: /*
2879: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 2880: * Returns 0 and a suitable display number for the DISPLAY variable
2881: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 2882: */
1.141 stevesk 2883: int
1.163 stevesk 2884: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 2885: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 2886: {
1.149 markus 2887: Channel *nc = NULL;
1.31 markus 2888: int display_number, sock;
2889: u_short port;
1.35 markus 2890: struct addrinfo hints, *ai, *aitop;
2891: char strport[NI_MAXSERV];
2892: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 2893:
1.224 markus 2894: if (chanids == NULL)
2895: return -1;
2896:
1.33 markus 2897: for (display_number = x11_display_offset;
1.148 deraadt 2898: display_number < MAX_DISPLAYS;
2899: display_number++) {
1.25 markus 2900: port = 6000 + display_number;
1.35 markus 2901: memset(&hints, 0, sizeof(hints));
2902: hints.ai_family = IPv4or6;
1.163 stevesk 2903: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 2904: hints.ai_socktype = SOCK_STREAM;
2905: snprintf(strport, sizeof strport, "%d", port);
2906: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 2907: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 2908: return -1;
1.25 markus 2909: }
1.35 markus 2910: for (ai = aitop; ai; ai = ai->ai_next) {
2911: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2912: continue;
1.189 markus 2913: sock = socket(ai->ai_family, ai->ai_socktype,
2914: ai->ai_protocol);
1.35 markus 2915: if (sock < 0) {
2916: error("socket: %.100s", strerror(errno));
1.203 markus 2917: freeaddrinfo(aitop);
1.141 stevesk 2918: return -1;
1.35 markus 2919: }
1.226 djm 2920: channel_set_reuseaddr(sock);
1.35 markus 2921: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 2922: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 2923: close(sock);
1.183 itojun 2924:
1.35 markus 2925: for (n = 0; n < num_socks; n++) {
2926: close(socks[n]);
2927: }
2928: num_socks = 0;
2929: break;
2930: }
2931: socks[num_socks++] = sock;
2932: if (num_socks == NUM_SOCKS)
2933: break;
1.25 markus 2934: }
1.83 stevesk 2935: freeaddrinfo(aitop);
1.35 markus 2936: if (num_socks > 0)
2937: break;
1.25 markus 2938: }
2939: if (display_number >= MAX_DISPLAYS) {
2940: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 2941: return -1;
1.25 markus 2942: }
2943: /* Start listening for connections on the socket. */
1.35 markus 2944: for (n = 0; n < num_socks; n++) {
2945: sock = socks[n];
1.199 markus 2946: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2947: error("listen: %.100s", strerror(errno));
2948: close(sock);
1.141 stevesk 2949: return -1;
1.35 markus 2950: }
1.25 markus 2951: }
1.35 markus 2952:
2953: /* Allocate a channel for each socket. */
1.242 djm 2954: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 2955: for (n = 0; n < num_socks; n++) {
2956: sock = socks[n];
1.149 markus 2957: nc = channel_new("x11 listener",
1.51 markus 2958: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2959: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 2960: 0, "X11 inet listener", 1);
1.167 markus 2961: nc->single_connection = single_connection;
1.224 markus 2962: (*chanids)[n] = nc->self;
1.35 markus 2963: }
1.224 markus 2964: (*chanids)[n] = -1;
1.1 deraadt 2965:
1.141 stevesk 2966: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 2967: *display_numberp = display_number;
2968: return (0);
1.1 deraadt 2969: }
2970:
1.127 itojun 2971: static int
1.77 markus 2972: connect_local_xsocket(u_int dnr)
1.1 deraadt 2973: {
1.25 markus 2974: int sock;
2975: struct sockaddr_un addr;
2976:
1.147 stevesk 2977: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2978: if (sock < 0)
2979: error("socket: %.100s", strerror(errno));
2980: memset(&addr, 0, sizeof(addr));
2981: addr.sun_family = AF_UNIX;
2982: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 2983: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 2984: return sock;
2985: close(sock);
1.25 markus 2986: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2987: return -1;
1.1 deraadt 2988: }
2989:
1.51 markus 2990: int
2991: x11_connect_display(void)
1.1 deraadt 2992: {
1.248 deraadt 2993: u_int display_number;
1.25 markus 2994: const char *display;
1.51 markus 2995: char buf[1024], *cp;
1.35 markus 2996: struct addrinfo hints, *ai, *aitop;
2997: char strport[NI_MAXSERV];
1.248 deraadt 2998: int gaierr, sock = 0;
1.25 markus 2999:
3000: /* Try to open a socket for the local X server. */
3001: display = getenv("DISPLAY");
3002: if (!display) {
3003: error("DISPLAY not set.");
1.51 markus 3004: return -1;
1.25 markus 3005: }
1.27 markus 3006: /*
3007: * Now we decode the value of the DISPLAY variable and make a
3008: * connection to the real X server.
3009: */
3010:
3011: /*
3012: * Check if it is a unix domain socket. Unix domain displays are in
3013: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3014: */
1.25 markus 3015: if (strncmp(display, "unix:", 5) == 0 ||
3016: display[0] == ':') {
3017: /* Connect to the unix domain socket. */
1.248 deraadt 3018: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3019: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3020: display);
1.51 markus 3021: return -1;
1.25 markus 3022: }
3023: /* Create a socket. */
3024: sock = connect_local_xsocket(display_number);
3025: if (sock < 0)
1.51 markus 3026: return -1;
1.25 markus 3027:
3028: /* OK, we now have a connection to the display. */
1.51 markus 3029: return sock;
1.25 markus 3030: }
1.27 markus 3031: /*
3032: * Connect to an inet socket. The DISPLAY value is supposedly
3033: * hostname:d[.s], where hostname may also be numeric IP address.
3034: */
1.145 stevesk 3035: strlcpy(buf, display, sizeof(buf));
1.25 markus 3036: cp = strchr(buf, ':');
3037: if (!cp) {
3038: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3039: return -1;
1.25 markus 3040: }
3041: *cp = 0;
1.27 markus 3042: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 3043: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 3044: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3045: display);
1.51 markus 3046: return -1;
1.25 markus 3047: }
1.35 markus 3048:
3049: /* Look up the host address */
3050: memset(&hints, 0, sizeof(hints));
3051: hints.ai_family = IPv4or6;
3052: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 3053: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 3054: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3055: error("%.100s: unknown host. (%s)", buf,
3056: ssh_gai_strerror(gaierr));
1.51 markus 3057: return -1;
1.25 markus 3058: }
1.35 markus 3059: for (ai = aitop; ai; ai = ai->ai_next) {
3060: /* Create a socket. */
1.189 markus 3061: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3062: if (sock < 0) {
1.194 markus 3063: debug2("socket: %.100s", strerror(errno));
1.41 markus 3064: continue;
3065: }
3066: /* Connect it to the display. */
3067: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 3068: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 3069: 6000 + display_number, strerror(errno));
3070: close(sock);
3071: continue;
3072: }
3073: /* Success */
3074: break;
1.35 markus 3075: }
3076: freeaddrinfo(aitop);
3077: if (!ai) {
1.248 deraadt 3078: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3079: strerror(errno));
1.51 markus 3080: return -1;
1.25 markus 3081: }
1.162 stevesk 3082: set_nodelay(sock);
1.51 markus 3083: return sock;
3084: }
3085:
3086: /*
3087: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3088: * the remote channel number. We should do whatever we want, and respond
3089: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3090: */
3091:
1.259 stevesk 3092: /* ARGSUSED */
1.51 markus 3093: void
1.154 markus 3094: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3095: {
1.113 markus 3096: Channel *c = NULL;
3097: int remote_id, sock = 0;
1.51 markus 3098: char *remote_host;
1.25 markus 3099:
1.113 markus 3100: debug("Received X11 open request.");
1.51 markus 3101:
1.113 markus 3102: remote_id = packet_get_int();
1.121 markus 3103:
3104: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3105: remote_host = packet_get_string(NULL);
1.51 markus 3106: } else {
3107: remote_host = xstrdup("unknown (remote did not supply name)");
3108: }
1.152 markus 3109: packet_check_eom();
1.25 markus 3110:
1.51 markus 3111: /* Obtain a connection to the real X display. */
3112: sock = x11_connect_display();
1.113 markus 3113: if (sock != -1) {
3114: /* Allocate a channel for this connection. */
3115: c = channel_new("connected x11 socket",
3116: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3117: remote_host, 1);
1.167 markus 3118: c->remote_id = remote_id;
3119: c->force_drain = 1;
1.113 markus 3120: }
1.190 markus 3121: xfree(remote_host);
1.113 markus 3122: if (c == NULL) {
1.51 markus 3123: /* Send refusal to the remote host. */
3124: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3125: packet_put_int(remote_id);
1.51 markus 3126: } else {
3127: /* Send a confirmation to the remote host. */
3128: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3129: packet_put_int(remote_id);
3130: packet_put_int(c->self);
1.51 markus 3131: }
1.113 markus 3132: packet_send();
1.72 markus 3133: }
3134:
3135: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 3136: /* ARGSUSED */
1.72 markus 3137: void
1.154 markus 3138: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3139: {
3140: int rchan = packet_get_int();
1.180 deraadt 3141:
1.143 deraadt 3142: switch (type) {
1.72 markus 3143: case SSH_SMSG_AGENT_OPEN:
3144: error("Warning: ssh server tried agent forwarding.");
3145: break;
3146: case SSH_SMSG_X11_OPEN:
3147: error("Warning: ssh server tried X11 forwarding.");
3148: break;
3149: default:
1.154 markus 3150: error("deny_input_open: type %d", type);
1.72 markus 3151: break;
3152: }
1.230 stevesk 3153: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3154: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3155: packet_put_int(rchan);
3156: packet_send();
1.1 deraadt 3157: }
3158:
1.27 markus 3159: /*
3160: * Requests forwarding of X11 connections, generates fake authentication
3161: * data, and enables authentication spoofing.
1.121 markus 3162: * This should be called in the client only.
1.27 markus 3163: */
1.49 markus 3164: void
1.215 djm 3165: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.51 markus 3166: const char *proto, const char *data)
1.1 deraadt 3167: {
1.77 markus 3168: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3169: u_int i, value;
1.25 markus 3170: char *new_data;
3171: int screen_number;
3172: const char *cp;
1.207 avsm 3173: u_int32_t rnd = 0;
1.25 markus 3174:
1.220 markus 3175: if (x11_saved_display == NULL)
3176: x11_saved_display = xstrdup(disp);
3177: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3178: error("x11_request_forwarding_with_spoofing: different "
3179: "$DISPLAY already forwarded");
3180: return;
3181: }
3182:
1.266 djm 3183: cp = strchr(disp, ':');
1.25 markus 3184: if (cp)
3185: cp = strchr(cp, '.');
3186: if (cp)
1.245 deraadt 3187: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3188: else
3189: screen_number = 0;
3190:
1.219 djm 3191: if (x11_saved_proto == NULL) {
3192: /* Save protocol name. */
3193: x11_saved_proto = xstrdup(proto);
3194: /*
1.221 djm 3195: * Extract real authentication data and generate fake data
1.219 djm 3196: * of the same length.
3197: */
3198: x11_saved_data = xmalloc(data_len);
3199: x11_fake_data = xmalloc(data_len);
3200: for (i = 0; i < data_len; i++) {
3201: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3202: fatal("x11_request_forwarding: bad "
3203: "authentication data: %.100s", data);
3204: if (i % 4 == 0)
3205: rnd = arc4random();
3206: x11_saved_data[i] = value;
3207: x11_fake_data[i] = rnd & 0xff;
3208: rnd >>= 8;
3209: }
3210: x11_saved_data_len = data_len;
3211: x11_fake_data_len = data_len;
1.25 markus 3212: }
3213:
3214: /* Convert the fake data into hex. */
1.219 djm 3215: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3216:
3217: /* Send the request packet. */
1.51 markus 3218: if (compat20) {
3219: channel_request_start(client_session_id, "x11-req", 0);
3220: packet_put_char(0); /* XXX bool single connection */
3221: } else {
3222: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3223: }
3224: packet_put_cstring(proto);
3225: packet_put_cstring(new_data);
1.25 markus 3226: packet_put_int(screen_number);
3227: packet_send();
3228: packet_write_wait();
3229: xfree(new_data);
1.1 deraadt 3230: }
3231:
1.121 markus 3232:
3233: /* -- agent forwarding */
3234:
1.1 deraadt 3235: /* Sends a message to the server to request authentication fd forwarding. */
3236:
1.49 markus 3237: void
1.142 itojun 3238: auth_request_forwarding(void)
1.1 deraadt 3239: {
1.25 markus 3240: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3241: packet_send();
3242: packet_write_wait();
1.1 deraadt 3243: }
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