Annotation of src/usr.bin/ssh/channels.c, Revision 1.158
1.1 deraadt 1: /*
1.26 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
5: * This file contains functions for generic socket connection forwarding.
6: * There is also code for initiating connection forwarding for X11 connections,
7: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 8: *
1.67 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
14: *
1.44 markus 15: * SSH2 support added by Markus Friedl.
1.156 markus 16: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 17: * Copyright (c) 1999 Dug Song. All rights reserved.
18: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
19: *
20: * Redistribution and use in source and binary forms, with or without
21: * modification, are permitted provided that the following conditions
22: * are met:
23: * 1. Redistributions of source code must retain the above copyright
24: * notice, this list of conditions and the following disclaimer.
25: * 2. Redistributions in binary form must reproduce the above copyright
26: * notice, this list of conditions and the following disclaimer in the
27: * documentation and/or other materials provided with the distribution.
28: *
29: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
30: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
31: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
32: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
33: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
34: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
38: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 39: */
1.1 deraadt 40:
41: #include "includes.h"
1.158 ! markus 42: RCSID("$OpenBSD: channels.c,v 1.157 2002/01/09 17:16:00 markus Exp $");
1.1 deraadt 43:
44: #include "ssh.h"
1.82 markus 45: #include "ssh1.h"
46: #include "ssh2.h"
1.1 deraadt 47: #include "packet.h"
48: #include "xmalloc.h"
49: #include "uidswap.h"
1.82 markus 50: #include "log.h"
51: #include "misc.h"
1.14 markus 52: #include "channels.h"
53: #include "compat.h"
1.82 markus 54: #include "canohost.h"
1.64 markus 55: #include "key.h"
56: #include "authfd.h"
1.147 stevesk 57: #include "pathnames.h"
1.44 markus 58:
1.1 deraadt 59:
1.121 markus 60: /* -- channel core */
1.12 markus 61:
1.27 markus 62: /*
63: * Pointer to an array containing all allocated channels. The array is
64: * dynamically extended as needed.
65: */
1.113 markus 66: static Channel **channels = NULL;
1.1 deraadt 67:
1.27 markus 68: /*
69: * Size of the channel array. All slots of the array must always be
1.113 markus 70: * initialized (at least the type field); unused slots set to NULL
1.27 markus 71: */
1.1 deraadt 72: static int channels_alloc = 0;
73:
1.27 markus 74: /*
75: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 76: * updated in channel_new.
1.27 markus 77: */
1.84 markus 78: static int channel_max_fd = 0;
1.1 deraadt 79:
80:
1.121 markus 81: /* -- tcp forwarding */
1.1 deraadt 82:
1.27 markus 83: /*
84: * Data structure for storing which hosts are permitted for forward requests.
85: * The local sides of any remote forwards are stored in this array to prevent
86: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
87: * network (which might be behind a firewall).
88: */
1.25 markus 89: typedef struct {
1.41 markus 90: char *host_to_connect; /* Connect to 'host'. */
91: u_short port_to_connect; /* Connect to 'port'. */
92: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 93: } ForwardPermission;
94:
95: /* List of all permitted host/port pairs to connect. */
96: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 97:
1.1 deraadt 98: /* Number of permitted host/port pairs in the array. */
99: static int num_permitted_opens = 0;
1.27 markus 100: /*
101: * If this is true, all opens are permitted. This is the case on the server
102: * on which we have to trust the client anyway, and the user could do
103: * anything after logging in anyway.
104: */
1.1 deraadt 105: static int all_opens_permitted = 0;
106:
1.121 markus 107:
108: /* -- X11 forwarding */
109:
110: /* Maximum number of fake X11 displays to try. */
111: #define MAX_DISPLAYS 1000
112:
113: /* Saved X11 authentication protocol name. */
114: static char *x11_saved_proto = NULL;
115:
116: /* Saved X11 authentication data. This is the real data. */
117: static char *x11_saved_data = NULL;
118: static u_int x11_saved_data_len = 0;
119:
120: /*
121: * Fake X11 authentication data. This is what the server will be sending us;
122: * we should replace any occurrences of this by the real data.
123: */
124: static char *x11_fake_data = NULL;
125: static u_int x11_fake_data_len;
126:
127:
128: /* -- agent forwarding */
129:
130: #define NUM_SOCKS 10
131:
132: /* Name and directory of socket for authentication agent forwarding. */
133: static char *auth_sock_name = NULL;
134: static char *auth_sock_dir = NULL;
135:
1.82 markus 136: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 137: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 138:
1.121 markus 139: /* helper */
1.127 itojun 140: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 141:
1.121 markus 142: /* -- channel core */
1.41 markus 143:
144: Channel *
145: channel_lookup(int id)
146: {
147: Channel *c;
1.113 markus 148:
1.63 provos 149: if (id < 0 || id > channels_alloc) {
1.41 markus 150: log("channel_lookup: %d: bad id", id);
151: return NULL;
152: }
1.113 markus 153: c = channels[id];
154: if (c == NULL) {
1.41 markus 155: log("channel_lookup: %d: bad id: channel free", id);
156: return NULL;
157: }
158: return c;
1.55 markus 159: }
160:
1.27 markus 161: /*
1.55 markus 162: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 163: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 164: */
1.1 deraadt 165:
1.127 itojun 166: static void
1.71 markus 167: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
168: int extusage, int nonblock)
1.1 deraadt 169: {
1.25 markus 170: /* Update the maximum file descriptor value. */
1.84 markus 171: channel_max_fd = MAX(channel_max_fd, rfd);
172: channel_max_fd = MAX(channel_max_fd, wfd);
173: channel_max_fd = MAX(channel_max_fd, efd);
174:
1.27 markus 175: /* XXX set close-on-exec -markus */
1.55 markus 176:
1.52 markus 177: c->rfd = rfd;
178: c->wfd = wfd;
179: c->sock = (rfd == wfd) ? rfd : -1;
180: c->efd = efd;
181: c->extended_usage = extusage;
1.71 markus 182:
1.91 markus 183: /* XXX ugly hack: nonblock is only set by the server */
184: if (nonblock && isatty(c->rfd)) {
1.94 markus 185: debug("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 186: c->isatty = 1;
187: if (!isatty(c->wfd)) {
1.94 markus 188: error("channel %d: wfd %d is not a tty?",
1.91 markus 189: c->self, c->wfd);
190: }
191: } else {
192: c->isatty = 0;
193: }
194:
1.71 markus 195: /* enable nonblocking mode */
196: if (nonblock) {
197: if (rfd != -1)
198: set_nonblock(rfd);
199: if (wfd != -1)
200: set_nonblock(wfd);
201: if (efd != -1)
202: set_nonblock(efd);
203: }
1.52 markus 204: }
205:
206: /*
207: * Allocate a new channel object and set its type and socket. This will cause
208: * remote_name to be freed.
209: */
210:
1.113 markus 211: Channel *
1.52 markus 212: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.71 markus 213: int window, int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 214: {
215: int i, found;
216: Channel *c;
1.25 markus 217:
218: /* Do initial allocation if this is the first call. */
219: if (channels_alloc == 0) {
1.44 markus 220: chan_init();
1.25 markus 221: channels_alloc = 10;
1.113 markus 222: channels = xmalloc(channels_alloc * sizeof(Channel *));
1.25 markus 223: for (i = 0; i < channels_alloc; i++)
1.113 markus 224: channels[i] = NULL;
1.126 markus 225: fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL);
1.25 markus 226: }
227: /* Try to find a free slot where to put the new channel. */
228: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 229: if (channels[i] == NULL) {
1.25 markus 230: /* Found a free slot. */
231: found = i;
232: break;
233: }
234: if (found == -1) {
1.27 markus 235: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 236: found = channels_alloc;
237: channels_alloc += 10;
1.70 markus 238: debug2("channel: expanding %d", channels_alloc);
1.113 markus 239: channels = xrealloc(channels, channels_alloc * sizeof(Channel *));
1.25 markus 240: for (i = found; i < channels_alloc; i++)
1.113 markus 241: channels[i] = NULL;
1.25 markus 242: }
1.113 markus 243: /* Initialize and return new channel. */
244: c = channels[found] = xmalloc(sizeof(Channel));
1.137 markus 245: memset(c, 0, sizeof(Channel));
1.25 markus 246: buffer_init(&c->input);
247: buffer_init(&c->output);
1.41 markus 248: buffer_init(&c->extended);
1.25 markus 249: chan_init_iostates(c);
1.71 markus 250: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
1.25 markus 251: c->self = found;
252: c->type = type;
1.41 markus 253: c->ctype = ctype;
1.51 markus 254: c->local_window = window;
255: c->local_window_max = window;
256: c->local_consumed = 0;
257: c->local_maxpacket = maxpack;
1.25 markus 258: c->remote_id = -1;
259: c->remote_name = remote_name;
1.41 markus 260: c->remote_window = 0;
261: c->remote_maxpacket = 0;
262: c->cb_fn = NULL;
263: c->cb_arg = NULL;
264: c->cb_event = 0;
1.133 markus 265: c->force_drain = 0;
1.149 markus 266: c->single_connection = 0;
1.131 markus 267: c->detach_user = NULL;
1.65 markus 268: c->input_filter = NULL;
1.25 markus 269: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 270: return c;
1.1 deraadt 271: }
1.52 markus 272:
1.132 markus 273: static int
274: channel_find_maxfd(void)
275: {
276: int i, max = 0;
277: Channel *c;
278:
279: for (i = 0; i < channels_alloc; i++) {
280: c = channels[i];
281: if (c != NULL) {
282: max = MAX(max, c->rfd);
283: max = MAX(max, c->wfd);
284: max = MAX(max, c->efd);
285: }
286: }
287: return max;
288: }
289:
290: int
291: channel_close_fd(int *fdp)
292: {
293: int ret = 0, fd = *fdp;
294:
295: if (fd != -1) {
296: ret = close(fd);
297: *fdp = -1;
298: if (fd == channel_max_fd)
299: channel_max_fd = channel_find_maxfd();
300: }
301: return ret;
302: }
303:
1.52 markus 304: /* Close all channel fd/socket. */
305:
1.127 itojun 306: static void
1.52 markus 307: channel_close_fds(Channel *c)
308: {
1.118 markus 309: debug3("channel_close_fds: channel %d: r %d w %d e %d",
310: c->self, c->rfd, c->wfd, c->efd);
311:
1.132 markus 312: channel_close_fd(&c->sock);
313: channel_close_fd(&c->rfd);
314: channel_close_fd(&c->wfd);
315: channel_close_fd(&c->efd);
1.121 markus 316: }
317:
318: /* Free the channel and close its fd/socket. */
319:
320: void
321: channel_free(Channel *c)
322: {
323: char *s;
324: int i, n;
325:
326: for (n = 0, i = 0; i < channels_alloc; i++)
327: if (channels[i])
328: n++;
329: debug("channel_free: channel %d: %s, nchannels %d", c->self,
330: c->remote_name ? c->remote_name : "???", n);
331:
332: s = channel_open_message();
333: debug3("channel_free: status: %s", s);
334: xfree(s);
335:
336: if (c->sock != -1)
337: shutdown(c->sock, SHUT_RDWR);
338: channel_close_fds(c);
339: buffer_free(&c->input);
340: buffer_free(&c->output);
341: buffer_free(&c->extended);
342: if (c->remote_name) {
343: xfree(c->remote_name);
344: c->remote_name = NULL;
345: }
346: channels[c->self] = NULL;
347: xfree(c);
348: }
349:
350: void
1.126 markus 351: channel_free_all(void)
1.121 markus 352: {
353: int i;
354:
1.126 markus 355: for (i = 0; i < channels_alloc; i++)
356: if (channels[i] != NULL)
357: channel_free(channels[i]);
1.131 markus 358: }
359:
1.121 markus 360: /*
361: * Closes the sockets/fds of all channels. This is used to close extra file
362: * descriptors after a fork.
363: */
364:
365: void
1.142 itojun 366: channel_close_all(void)
1.121 markus 367: {
368: int i;
369:
370: for (i = 0; i < channels_alloc; i++)
371: if (channels[i] != NULL)
372: channel_close_fds(channels[i]);
373: }
374:
375: /*
1.131 markus 376: * Stop listening to channels.
377: */
378:
379: void
380: channel_stop_listening(void)
381: {
382: int i;
383: Channel *c;
384:
385: for (i = 0; i < channels_alloc; i++) {
386: c = channels[i];
387: if (c != NULL) {
388: switch (c->type) {
389: case SSH_CHANNEL_AUTH_SOCKET:
390: case SSH_CHANNEL_PORT_LISTENER:
391: case SSH_CHANNEL_RPORT_LISTENER:
392: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 393: channel_close_fd(&c->sock);
1.131 markus 394: channel_free(c);
395: break;
396: }
397: }
398: }
399: }
400:
401: /*
1.121 markus 402: * Returns true if no channel has too much buffered data, and false if one or
403: * more channel is overfull.
404: */
405:
406: int
1.142 itojun 407: channel_not_very_much_buffered_data(void)
1.121 markus 408: {
409: u_int i;
410: Channel *c;
411:
412: for (i = 0; i < channels_alloc; i++) {
413: c = channels[i];
414: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 415: #if 0
416: if (!compat20 &&
417: buffer_len(&c->input) > packet_get_maxsize()) {
1.121 markus 418: debug("channel %d: big input buffer %d",
419: c->self, buffer_len(&c->input));
420: return 0;
421: }
1.136 markus 422: #endif
1.121 markus 423: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.136 markus 424: debug("channel %d: big output buffer %d > %d",
425: c->self, buffer_len(&c->output),
426: packet_get_maxsize());
1.121 markus 427: return 0;
428: }
429: }
430: }
431: return 1;
432: }
433:
434: /* Returns true if any channel is still open. */
435:
436: int
1.142 itojun 437: channel_still_open(void)
1.121 markus 438: {
439: int i;
440: Channel *c;
441:
442: for (i = 0; i < channels_alloc; i++) {
443: c = channels[i];
444: if (c == NULL)
445: continue;
446: switch (c->type) {
447: case SSH_CHANNEL_X11_LISTENER:
448: case SSH_CHANNEL_PORT_LISTENER:
449: case SSH_CHANNEL_RPORT_LISTENER:
450: case SSH_CHANNEL_CLOSED:
451: case SSH_CHANNEL_AUTH_SOCKET:
452: case SSH_CHANNEL_DYNAMIC:
453: case SSH_CHANNEL_CONNECTING:
454: case SSH_CHANNEL_ZOMBIE:
455: continue;
456: case SSH_CHANNEL_LARVAL:
457: if (!compat20)
458: fatal("cannot happen: SSH_CHANNEL_LARVAL");
459: continue;
460: case SSH_CHANNEL_OPENING:
461: case SSH_CHANNEL_OPEN:
462: case SSH_CHANNEL_X11_OPEN:
463: return 1;
464: case SSH_CHANNEL_INPUT_DRAINING:
465: case SSH_CHANNEL_OUTPUT_DRAINING:
466: if (!compat13)
467: fatal("cannot happen: OUT_DRAIN");
468: return 1;
469: default:
470: fatal("channel_still_open: bad channel type %d", c->type);
471: /* NOTREACHED */
472: }
473: }
474: return 0;
475: }
476:
477: /* Returns the id of an open channel suitable for keepaliving */
478:
479: int
1.142 itojun 480: channel_find_open(void)
1.121 markus 481: {
482: int i;
483: Channel *c;
484:
485: for (i = 0; i < channels_alloc; i++) {
486: c = channels[i];
487: if (c == NULL)
488: continue;
489: switch (c->type) {
490: case SSH_CHANNEL_CLOSED:
491: case SSH_CHANNEL_DYNAMIC:
492: case SSH_CHANNEL_X11_LISTENER:
493: case SSH_CHANNEL_PORT_LISTENER:
494: case SSH_CHANNEL_RPORT_LISTENER:
495: case SSH_CHANNEL_OPENING:
496: case SSH_CHANNEL_CONNECTING:
497: case SSH_CHANNEL_ZOMBIE:
498: continue;
499: case SSH_CHANNEL_LARVAL:
500: case SSH_CHANNEL_AUTH_SOCKET:
501: case SSH_CHANNEL_OPEN:
502: case SSH_CHANNEL_X11_OPEN:
503: return i;
504: case SSH_CHANNEL_INPUT_DRAINING:
505: case SSH_CHANNEL_OUTPUT_DRAINING:
506: if (!compat13)
507: fatal("cannot happen: OUT_DRAIN");
508: return i;
509: default:
510: fatal("channel_find_open: bad channel type %d", c->type);
511: /* NOTREACHED */
512: }
513: }
514: return -1;
515: }
516:
517:
518: /*
519: * Returns a message describing the currently open forwarded connections,
520: * suitable for sending to the client. The message contains crlf pairs for
521: * newlines.
522: */
523:
524: char *
1.142 itojun 525: channel_open_message(void)
1.121 markus 526: {
527: Buffer buffer;
528: Channel *c;
529: char buf[1024], *cp;
530: int i;
531:
532: buffer_init(&buffer);
533: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
534: buffer_append(&buffer, buf, strlen(buf));
535: for (i = 0; i < channels_alloc; i++) {
536: c = channels[i];
537: if (c == NULL)
538: continue;
539: switch (c->type) {
540: case SSH_CHANNEL_X11_LISTENER:
541: case SSH_CHANNEL_PORT_LISTENER:
542: case SSH_CHANNEL_RPORT_LISTENER:
543: case SSH_CHANNEL_CLOSED:
544: case SSH_CHANNEL_AUTH_SOCKET:
545: case SSH_CHANNEL_ZOMBIE:
546: continue;
547: case SSH_CHANNEL_LARVAL:
548: case SSH_CHANNEL_OPENING:
549: case SSH_CHANNEL_CONNECTING:
550: case SSH_CHANNEL_DYNAMIC:
551: case SSH_CHANNEL_OPEN:
552: case SSH_CHANNEL_X11_OPEN:
553: case SSH_CHANNEL_INPUT_DRAINING:
554: case SSH_CHANNEL_OUTPUT_DRAINING:
555: snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
556: c->self, c->remote_name,
557: c->type, c->remote_id,
558: c->istate, buffer_len(&c->input),
559: c->ostate, buffer_len(&c->output),
560: c->rfd, c->wfd);
561: buffer_append(&buffer, buf, strlen(buf));
562: continue;
563: default:
564: fatal("channel_open_message: bad channel type %d", c->type);
565: /* NOTREACHED */
566: }
567: }
568: buffer_append(&buffer, "\0", 1);
569: cp = xstrdup(buffer_ptr(&buffer));
570: buffer_free(&buffer);
571: return cp;
572: }
573:
574: void
575: channel_send_open(int id)
576: {
577: Channel *c = channel_lookup(id);
578: if (c == NULL) {
579: log("channel_send_open: %d: bad id", id);
580: return;
581: }
582: debug("send channel open %d", id);
583: packet_start(SSH2_MSG_CHANNEL_OPEN);
584: packet_put_cstring(c->ctype);
585: packet_put_int(c->self);
586: packet_put_int(c->local_window);
587: packet_put_int(c->local_maxpacket);
588: packet_send();
589: }
590:
591: void
592: channel_request(int id, char *service, int wantconfirm)
593: {
594: channel_request_start(id, service, wantconfirm);
595: packet_send();
596: debug("channel request %d: %s", id, service) ;
597: }
598: void
599: channel_request_start(int id, char *service, int wantconfirm)
600: {
601: Channel *c = channel_lookup(id);
602: if (c == NULL) {
603: log("channel_request: %d: bad id", id);
604: return;
605: }
606: packet_start(SSH2_MSG_CHANNEL_REQUEST);
607: packet_put_int(c->remote_id);
608: packet_put_cstring(service);
609: packet_put_char(wantconfirm);
610: }
611: void
612: channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
613: {
614: Channel *c = channel_lookup(id);
615: if (c == NULL) {
616: log("channel_register_callback: %d: bad id", id);
617: return;
618: }
619: c->cb_event = mtype;
620: c->cb_fn = fn;
621: c->cb_arg = arg;
622: }
623: void
624: channel_register_cleanup(int id, channel_callback_fn *fn)
625: {
626: Channel *c = channel_lookup(id);
627: if (c == NULL) {
628: log("channel_register_cleanup: %d: bad id", id);
629: return;
630: }
1.131 markus 631: c->detach_user = fn;
1.121 markus 632: }
633: void
634: channel_cancel_cleanup(int id)
635: {
636: Channel *c = channel_lookup(id);
637: if (c == NULL) {
638: log("channel_cancel_cleanup: %d: bad id", id);
639: return;
1.52 markus 640: }
1.131 markus 641: c->detach_user = NULL;
1.121 markus 642: }
643: void
644: channel_register_filter(int id, channel_filter_fn *fn)
645: {
646: Channel *c = channel_lookup(id);
647: if (c == NULL) {
648: log("channel_register_filter: %d: bad id", id);
649: return;
1.52 markus 650: }
1.121 markus 651: c->input_filter = fn;
1.52 markus 652: }
653:
1.49 markus 654: void
1.121 markus 655: channel_set_fds(int id, int rfd, int wfd, int efd,
656: int extusage, int nonblock)
1.1 deraadt 657: {
1.121 markus 658: Channel *c = channel_lookup(id);
659: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
660: fatal("channel_activate for non-larval channel %d.", id);
661: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
662: c->type = SSH_CHANNEL_OPEN;
663: /* XXX window size? */
664: c->local_window = c->local_window_max = c->local_maxpacket * 2;
665: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
666: packet_put_int(c->remote_id);
667: packet_put_int(c->local_window);
668: packet_send();
1.1 deraadt 669: }
670:
1.27 markus 671: /*
1.41 markus 672: * 'channel_pre*' are called just before select() to add any bits relevant to
673: * channels in the select bitmasks.
674: */
675: /*
676: * 'channel_post*': perform any appropriate operations for channels which
677: * have events pending.
1.27 markus 678: */
1.41 markus 679: typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
680: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
681: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
682:
1.127 itojun 683: static void
1.41 markus 684: channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
685: {
686: FD_SET(c->sock, readset);
687: }
688:
1.127 itojun 689: static void
1.75 markus 690: channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
691: {
692: debug3("channel %d: waiting for connection", c->self);
693: FD_SET(c->sock, writeset);
694: }
695:
1.127 itojun 696: static void
1.41 markus 697: channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
698: {
699: if (buffer_len(&c->input) < packet_get_maxsize())
700: FD_SET(c->sock, readset);
701: if (buffer_len(&c->output) > 0)
702: FD_SET(c->sock, writeset);
703: }
1.1 deraadt 704:
1.127 itojun 705: static void
1.157 markus 706: channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 707: {
1.157 markus 708: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 709:
1.44 markus 710: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 711: limit > 0 &&
712: buffer_len(&c->input) < limit)
1.44 markus 713: FD_SET(c->rfd, readset);
714: if (c->ostate == CHAN_OUTPUT_OPEN ||
715: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
716: if (buffer_len(&c->output) > 0) {
717: FD_SET(c->wfd, writeset);
718: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
719: chan_obuf_empty(c);
720: }
721: }
722: /** XXX check close conditions, too */
1.157 markus 723: if (compat20 && c->efd != -1) {
1.44 markus 724: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
725: buffer_len(&c->extended) > 0)
726: FD_SET(c->efd, writeset);
727: else if (c->extended_usage == CHAN_EXTENDED_READ &&
728: buffer_len(&c->extended) < c->remote_window)
729: FD_SET(c->efd, readset);
730: }
731: }
732:
1.127 itojun 733: static void
1.41 markus 734: channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
735: {
736: if (buffer_len(&c->input) == 0) {
737: packet_start(SSH_MSG_CHANNEL_CLOSE);
738: packet_put_int(c->remote_id);
739: packet_send();
740: c->type = SSH_CHANNEL_CLOSED;
1.105 markus 741: debug("channel %d: closing after input drain.", c->self);
1.41 markus 742: }
743: }
744:
1.127 itojun 745: static void
1.41 markus 746: channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
747: {
748: if (buffer_len(&c->output) == 0)
1.113 markus 749: chan_mark_dead(c);
1.49 markus 750: else
1.41 markus 751: FD_SET(c->sock, writeset);
752: }
753:
754: /*
755: * This is a special state for X11 authentication spoofing. An opened X11
756: * connection (when authentication spoofing is being done) remains in this
757: * state until the first packet has been completely read. The authentication
758: * data in that packet is then substituted by the real data if it matches the
759: * fake data, and the channel is put into normal mode.
1.51 markus 760: * XXX All this happens at the client side.
1.121 markus 761: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 762: */
1.127 itojun 763: static int
1.121 markus 764: x11_open_helper(Buffer *b)
1.1 deraadt 765: {
1.77 markus 766: u_char *ucp;
767: u_int proto_len, data_len;
1.25 markus 768:
1.41 markus 769: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 770: if (buffer_len(b) < 12)
1.41 markus 771: return 0;
772:
773: /* Parse the lengths of variable-length fields. */
1.155 stevesk 774: ucp = buffer_ptr(b);
1.41 markus 775: if (ucp[0] == 0x42) { /* Byte order MSB first. */
776: proto_len = 256 * ucp[6] + ucp[7];
777: data_len = 256 * ucp[8] + ucp[9];
778: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
779: proto_len = ucp[6] + 256 * ucp[7];
780: data_len = ucp[8] + 256 * ucp[9];
781: } else {
782: debug("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 783: ucp[0]);
1.41 markus 784: return -1;
785: }
786:
787: /* Check if the whole packet is in buffer. */
1.121 markus 788: if (buffer_len(b) <
1.41 markus 789: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
790: return 0;
791:
792: /* Check if authentication protocol matches. */
793: if (proto_len != strlen(x11_saved_proto) ||
794: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
795: debug("X11 connection uses different authentication protocol.");
796: return -1;
797: }
798: /* Check if authentication data matches our fake data. */
799: if (data_len != x11_fake_data_len ||
800: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
801: x11_fake_data, x11_fake_data_len) != 0) {
802: debug("X11 auth data does not match fake data.");
803: return -1;
804: }
805: /* Check fake data length */
806: if (x11_fake_data_len != x11_saved_data_len) {
807: error("X11 fake_data_len %d != saved_data_len %d",
808: x11_fake_data_len, x11_saved_data_len);
809: return -1;
810: }
811: /*
812: * Received authentication protocol and data match
813: * our fake data. Substitute the fake data with real
814: * data.
815: */
816: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
817: x11_saved_data, x11_saved_data_len);
818: return 1;
819: }
820:
1.127 itojun 821: static void
1.41 markus 822: channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
823: {
1.121 markus 824: int ret = x11_open_helper(&c->output);
1.41 markus 825: if (ret == 1) {
826: /* Start normal processing for the channel. */
827: c->type = SSH_CHANNEL_OPEN;
1.47 markus 828: channel_pre_open_13(c, readset, writeset);
1.41 markus 829: } else if (ret == -1) {
830: /*
831: * We have received an X11 connection that has bad
832: * authentication information.
833: */
1.98 millert 834: log("X11 connection rejected because of wrong authentication.");
1.41 markus 835: buffer_clear(&c->input);
836: buffer_clear(&c->output);
1.132 markus 837: channel_close_fd(&c->sock);
1.41 markus 838: c->sock = -1;
839: c->type = SSH_CHANNEL_CLOSED;
840: packet_start(SSH_MSG_CHANNEL_CLOSE);
841: packet_put_int(c->remote_id);
842: packet_send();
843: }
844: }
1.25 markus 845:
1.127 itojun 846: static void
1.51 markus 847: channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 848: {
1.121 markus 849: int ret = x11_open_helper(&c->output);
1.133 markus 850:
851: /* c->force_drain = 1; */
852:
1.41 markus 853: if (ret == 1) {
854: c->type = SSH_CHANNEL_OPEN;
1.157 markus 855: channel_pre_open(c, readset, writeset);
1.41 markus 856: } else if (ret == -1) {
1.156 markus 857: log("X11 connection rejected because of wrong authentication.");
1.41 markus 858: debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 859: chan_read_failed(c);
860: buffer_clear(&c->input);
861: chan_ibuf_empty(c);
862: buffer_clear(&c->output);
863: /* for proto v1, the peer will send an IEOF */
864: if (compat20)
865: chan_write_failed(c);
866: else
867: c->type = SSH_CHANNEL_OPEN;
1.41 markus 868: debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
869: }
870: }
1.25 markus 871:
1.104 markus 872: /* try to decode a socks4 header */
1.127 itojun 873: static int
1.104 markus 874: channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
1.103 markus 875: {
876: u_char *p, *host;
1.109 markus 877: int len, have, i, found;
1.148 deraadt 878: char username[256];
1.103 markus 879: struct {
880: u_int8_t version;
881: u_int8_t command;
882: u_int16_t dest_port;
1.104 markus 883: struct in_addr dest_addr;
1.103 markus 884: } s4_req, s4_rsp;
885:
1.104 markus 886: debug2("channel %d: decode socks4", c->self);
1.109 markus 887:
888: have = buffer_len(&c->input);
889: len = sizeof(s4_req);
890: if (have < len)
891: return 0;
892: p = buffer_ptr(&c->input);
893: for (found = 0, i = len; i < have; i++) {
894: if (p[i] == '\0') {
895: found = 1;
896: break;
897: }
898: if (i > 1024) {
899: /* the peer is probably sending garbage */
900: debug("channel %d: decode socks4: too long",
901: c->self);
902: return -1;
903: }
904: }
905: if (!found)
906: return 0;
1.103 markus 907: buffer_get(&c->input, (char *)&s4_req.version, 1);
908: buffer_get(&c->input, (char *)&s4_req.command, 1);
909: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 910: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 911: have = buffer_len(&c->input);
1.103 markus 912: p = buffer_ptr(&c->input);
913: len = strlen(p);
1.106 markus 914: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 915: if (len > have)
1.104 markus 916: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 917: c->self, len, have);
918: strlcpy(username, p, sizeof(username));
919: buffer_consume(&c->input, len);
920: buffer_consume(&c->input, 1); /* trailing '\0' */
921:
1.104 markus 922: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 923: strlcpy(c->path, host, sizeof(c->path));
924: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 925:
1.106 markus 926: debug("channel %d: dynamic request: socks4 host %s port %u command %u",
927: c->self, host, c->host_port, s4_req.command);
1.103 markus 928:
1.104 markus 929: if (s4_req.command != 1) {
930: debug("channel %d: cannot handle: socks4 cn %d",
931: c->self, s4_req.command);
932: return -1;
1.103 markus 933: }
1.104 markus 934: s4_rsp.version = 0; /* vn: 0 for reply */
935: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 936: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 937: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.103 markus 938: buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
1.104 markus 939: return 1;
940: }
941:
942: /* dynamic port forwarding */
1.127 itojun 943: static void
1.104 markus 944: channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
945: {
946: u_char *p;
947: int have, ret;
1.103 markus 948:
1.104 markus 949: have = buffer_len(&c->input);
1.137 markus 950: c->delayed = 0;
1.104 markus 951: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 952: /* buffer_dump(&c->input); */
1.104 markus 953: /* check if the fixed size part of the packet is in buffer. */
954: if (have < 4) {
955: /* need more */
956: FD_SET(c->sock, readset);
957: return;
958: }
959: /* try to guess the protocol */
960: p = buffer_ptr(&c->input);
961: switch (p[0]) {
962: case 0x04:
963: ret = channel_decode_socks4(c, readset, writeset);
964: break;
965: default:
966: ret = -1;
967: break;
968: }
969: if (ret < 0) {
1.113 markus 970: chan_mark_dead(c);
1.104 markus 971: } else if (ret == 0) {
972: debug2("channel %d: pre_dynamic: need more", c->self);
973: /* need more */
974: FD_SET(c->sock, readset);
975: } else {
976: /* switch to the next state */
977: c->type = SSH_CHANNEL_OPENING;
978: port_open_helper(c, "direct-tcpip");
979: }
1.103 markus 980: }
981:
1.41 markus 982: /* This is our fake X11 server socket. */
1.127 itojun 983: static void
1.41 markus 984: channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
985: {
1.113 markus 986: Channel *nc;
1.41 markus 987: struct sockaddr addr;
1.146 stevesk 988: int newsock, on = 1;
1.41 markus 989: socklen_t addrlen;
1.85 markus 990: char buf[16384], *remote_ipaddr;
1.51 markus 991: int remote_port;
1.25 markus 992:
1.41 markus 993: if (FD_ISSET(c->sock, readset)) {
994: debug("X11 connection requested.");
995: addrlen = sizeof(addr);
996: newsock = accept(c->sock, &addr, &addrlen);
1.149 markus 997: if (c->single_connection) {
998: debug("single_connection: closing X11 listener.");
999: channel_close_fd(&c->sock);
1000: chan_mark_dead(c);
1001: }
1.41 markus 1002: if (newsock < 0) {
1003: error("accept: %.100s", strerror(errno));
1004: return;
1005: }
1.146 stevesk 1006: if (setsockopt(newsock, IPPROTO_TCP, TCP_NODELAY, &on,
1007: sizeof on) == -1)
1008: error("setsockopt TCP_NODELAY: %.100s",
1009: strerror(errno));
1.85 markus 1010: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1011: remote_port = get_peer_port(newsock);
1.41 markus 1012: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1013: remote_ipaddr, remote_port);
1.51 markus 1014:
1.113 markus 1015: nc = channel_new("accepted x11 socket",
1.51 markus 1016: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1017: c->local_window_max, c->local_maxpacket,
1.71 markus 1018: 0, xstrdup(buf), 1);
1.113 markus 1019: if (nc == NULL) {
1020: close(newsock);
1021: xfree(remote_ipaddr);
1022: return;
1023: }
1.51 markus 1024: if (compat20) {
1025: packet_start(SSH2_MSG_CHANNEL_OPEN);
1026: packet_put_cstring("x11");
1.113 markus 1027: packet_put_int(nc->self);
1.149 markus 1028: packet_put_int(nc->local_window_max);
1029: packet_put_int(nc->local_maxpacket);
1.85 markus 1030: /* originator ipaddr and port */
1031: packet_put_cstring(remote_ipaddr);
1.57 markus 1032: if (datafellows & SSH_BUG_X11FWD) {
1033: debug("ssh2 x11 bug compat mode");
1034: } else {
1035: packet_put_int(remote_port);
1036: }
1.51 markus 1037: packet_send();
1038: } else {
1039: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1040: packet_put_int(nc->self);
1.121 markus 1041: if (packet_get_protocol_flags() &
1042: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1043: packet_put_cstring(buf);
1.51 markus 1044: packet_send();
1045: }
1.85 markus 1046: xfree(remote_ipaddr);
1.41 markus 1047: }
1048: }
1.25 markus 1049:
1.127 itojun 1050: static void
1.103 markus 1051: port_open_helper(Channel *c, char *rtype)
1052: {
1053: int direct;
1054: char buf[1024];
1055: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1056: u_short remote_port = get_peer_port(c->sock);
1057:
1058: direct = (strcmp(rtype, "direct-tcpip") == 0);
1059:
1060: snprintf(buf, sizeof buf,
1061: "%s: listening port %d for %.100s port %d, "
1062: "connect from %.200s port %d",
1063: rtype, c->listening_port, c->path, c->host_port,
1064: remote_ipaddr, remote_port);
1065:
1066: xfree(c->remote_name);
1067: c->remote_name = xstrdup(buf);
1068:
1069: if (compat20) {
1070: packet_start(SSH2_MSG_CHANNEL_OPEN);
1071: packet_put_cstring(rtype);
1072: packet_put_int(c->self);
1073: packet_put_int(c->local_window_max);
1074: packet_put_int(c->local_maxpacket);
1075: if (direct) {
1076: /* target host, port */
1077: packet_put_cstring(c->path);
1078: packet_put_int(c->host_port);
1079: } else {
1080: /* listen address, port */
1081: packet_put_cstring(c->path);
1082: packet_put_int(c->listening_port);
1083: }
1084: /* originator host and port */
1085: packet_put_cstring(remote_ipaddr);
1086: packet_put_int(remote_port);
1087: packet_send();
1088: } else {
1089: packet_start(SSH_MSG_PORT_OPEN);
1090: packet_put_int(c->self);
1091: packet_put_cstring(c->path);
1092: packet_put_int(c->host_port);
1.121 markus 1093: if (packet_get_protocol_flags() &
1094: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1095: packet_put_cstring(c->remote_name);
1096: packet_send();
1097: }
1098: xfree(remote_ipaddr);
1099: }
1100:
1.41 markus 1101: /*
1102: * This socket is listening for connections to a forwarded TCP/IP port.
1103: */
1.127 itojun 1104: static void
1.41 markus 1105: channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1106: {
1.103 markus 1107: Channel *nc;
1.41 markus 1108: struct sockaddr addr;
1.113 markus 1109: int newsock, nextstate;
1.41 markus 1110: socklen_t addrlen;
1.103 markus 1111: char *rtype;
1.73 markus 1112:
1.41 markus 1113: if (FD_ISSET(c->sock, readset)) {
1114: debug("Connection to port %d forwarding "
1115: "to %.100s port %d requested.",
1116: c->listening_port, c->path, c->host_port);
1.103 markus 1117:
1.137 markus 1118: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1119: nextstate = SSH_CHANNEL_OPENING;
1120: rtype = "forwarded-tcpip";
1121: } else {
1122: if (c->host_port == 0) {
1123: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1124: rtype = "dynamic-tcpip";
1.137 markus 1125: } else {
1126: nextstate = SSH_CHANNEL_OPENING;
1127: rtype = "direct-tcpip";
1128: }
1129: }
1.103 markus 1130:
1.41 markus 1131: addrlen = sizeof(addr);
1132: newsock = accept(c->sock, &addr, &addrlen);
1133: if (newsock < 0) {
1134: error("accept: %.100s", strerror(errno));
1135: return;
1136: }
1.113 markus 1137: nc = channel_new(rtype,
1.103 markus 1138: nextstate, newsock, newsock, -1,
1.41 markus 1139: c->local_window_max, c->local_maxpacket,
1.103 markus 1140: 0, xstrdup(rtype), 1);
1141: if (nc == NULL) {
1.113 markus 1142: error("channel_post_port_listener: no new channel:");
1143: close(newsock);
1.103 markus 1144: return;
1.41 markus 1145: }
1.103 markus 1146: nc->listening_port = c->listening_port;
1147: nc->host_port = c->host_port;
1148: strlcpy(nc->path, c->path, sizeof(nc->path));
1149:
1.137 markus 1150: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1151: /*
1152: * do not call the channel_post handler until
1153: * this flag has been reset by a pre-handler.
1154: * otherwise the FD_ISSET calls might overflow
1155: */
1156: nc->delayed = 1;
1157: } else {
1.103 markus 1158: port_open_helper(nc, rtype);
1.137 markus 1159: }
1.41 markus 1160: }
1161: }
1.25 markus 1162:
1.41 markus 1163: /*
1164: * This is the authentication agent socket listening for connections from
1165: * clients.
1166: */
1.127 itojun 1167: static void
1.41 markus 1168: channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1169: {
1.113 markus 1170: Channel *nc;
1.121 markus 1171: char *name;
1.113 markus 1172: int newsock;
1.41 markus 1173: struct sockaddr addr;
1174: socklen_t addrlen;
1.25 markus 1175:
1.41 markus 1176: if (FD_ISSET(c->sock, readset)) {
1177: addrlen = sizeof(addr);
1178: newsock = accept(c->sock, &addr, &addrlen);
1179: if (newsock < 0) {
1180: error("accept from auth socket: %.100s", strerror(errno));
1181: return;
1182: }
1.121 markus 1183: name = xstrdup("accepted auth socket");
1.113 markus 1184: nc = channel_new("accepted auth socket",
1.73 markus 1185: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1186: c->local_window_max, c->local_maxpacket,
1.121 markus 1187: 0, name, 1);
1.113 markus 1188: if (nc == NULL) {
1189: error("channel_post_auth_listener: channel_new failed");
1.121 markus 1190: xfree(name);
1.113 markus 1191: close(newsock);
1192: }
1.73 markus 1193: if (compat20) {
1194: packet_start(SSH2_MSG_CHANNEL_OPEN);
1195: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1196: packet_put_int(nc->self);
1.73 markus 1197: packet_put_int(c->local_window_max);
1198: packet_put_int(c->local_maxpacket);
1199: } else {
1200: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1201: packet_put_int(nc->self);
1.73 markus 1202: }
1.41 markus 1203: packet_send();
1204: }
1205: }
1.25 markus 1206:
1.127 itojun 1207: static void
1.75 markus 1208: channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1209: {
1.114 markus 1210: int err = 0;
1.129 stevesk 1211: socklen_t sz = sizeof(err);
1.114 markus 1212:
1.75 markus 1213: if (FD_ISSET(c->sock, writeset)) {
1.114 markus 1214: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
1215: &sz) < 0) {
1216: err = errno;
1217: error("getsockopt SO_ERROR failed");
1218: }
1219: if (err == 0) {
1220: debug("channel %d: connected", c->self);
1221: c->type = SSH_CHANNEL_OPEN;
1222: if (compat20) {
1223: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1224: packet_put_int(c->remote_id);
1225: packet_put_int(c->self);
1226: packet_put_int(c->local_window);
1227: packet_put_int(c->local_maxpacket);
1228: } else {
1229: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1230: packet_put_int(c->remote_id);
1231: packet_put_int(c->self);
1232: }
1.75 markus 1233: } else {
1.114 markus 1234: debug("channel %d: not connected: %s",
1235: c->self, strerror(err));
1236: if (compat20) {
1237: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1238: packet_put_int(c->remote_id);
1239: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1240: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1241: packet_put_cstring(strerror(err));
1242: packet_put_cstring("");
1243: }
1.75 markus 1244: } else {
1.114 markus 1245: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1246: packet_put_int(c->remote_id);
1.75 markus 1247: }
1.114 markus 1248: chan_mark_dead(c);
1.75 markus 1249: }
1.114 markus 1250: packet_send();
1.75 markus 1251: }
1252: }
1253:
1.127 itojun 1254: static int
1.41 markus 1255: channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1256: {
1257: char buf[16*1024];
1258: int len;
1.25 markus 1259:
1.118 markus 1260: if (c->rfd != -1 &&
1.41 markus 1261: FD_ISSET(c->rfd, readset)) {
1262: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1263: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1264: return 1;
1.41 markus 1265: if (len <= 0) {
1.51 markus 1266: debug("channel %d: read<=0 rfd %d len %d",
1.41 markus 1267: c->self, c->rfd, len);
1.104 markus 1268: if (c->type != SSH_CHANNEL_OPEN) {
1269: debug("channel %d: not open", c->self);
1.113 markus 1270: chan_mark_dead(c);
1.103 markus 1271: return -1;
1.104 markus 1272: } else if (compat13) {
1.158 ! markus 1273: buffer_clear(&c->output);
1.41 markus 1274: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.121 markus 1275: debug("channel %d: input draining.", c->self);
1.25 markus 1276: } else {
1.41 markus 1277: chan_read_failed(c);
1.25 markus 1278: }
1.41 markus 1279: return -1;
1280: }
1.143 deraadt 1281: if (c->input_filter != NULL) {
1.66 markus 1282: if (c->input_filter(c, buf, len) == -1) {
1.105 markus 1283: debug("channel %d: filter stops", c->self);
1.65 markus 1284: chan_read_failed(c);
1285: }
1286: } else {
1287: buffer_append(&c->input, buf, len);
1288: }
1.41 markus 1289: }
1290: return 1;
1291: }
1.127 itojun 1292: static int
1.41 markus 1293: channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1294: {
1.95 markus 1295: struct termios tio;
1.134 markus 1296: u_char *data;
1297: u_int dlen;
1.41 markus 1298: int len;
1.25 markus 1299:
1.41 markus 1300: /* Send buffered output data to the socket. */
1.118 markus 1301: if (c->wfd != -1 &&
1.41 markus 1302: FD_ISSET(c->wfd, writeset) &&
1303: buffer_len(&c->output) > 0) {
1.134 markus 1304: data = buffer_ptr(&c->output);
1305: dlen = buffer_len(&c->output);
1306: len = write(c->wfd, data, dlen);
1.53 markus 1307: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1308: return 1;
1.41 markus 1309: if (len <= 0) {
1.104 markus 1310: if (c->type != SSH_CHANNEL_OPEN) {
1311: debug("channel %d: not open", c->self);
1.113 markus 1312: chan_mark_dead(c);
1.104 markus 1313: return -1;
1314: } else if (compat13) {
1.158 ! markus 1315: buffer_clear(&c->output);
1.121 markus 1316: debug("channel %d: input draining.", c->self);
1.41 markus 1317: c->type = SSH_CHANNEL_INPUT_DRAINING;
1318: } else {
1319: chan_write_failed(c);
1320: }
1321: return -1;
1.91 markus 1322: }
1.134 markus 1323: if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
1.91 markus 1324: if (tcgetattr(c->wfd, &tio) == 0 &&
1325: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1326: /*
1327: * Simulate echo to reduce the impact of
1.96 markus 1328: * traffic analysis. We need to match the
1.95 markus 1329: * size of a SSH2_MSG_CHANNEL_DATA message
1330: * (4 byte channel id + data)
1.91 markus 1331: */
1.95 markus 1332: packet_send_ignore(4 + len);
1.91 markus 1333: packet_send();
1334: }
1.25 markus 1335: }
1.41 markus 1336: buffer_consume(&c->output, len);
1.44 markus 1337: if (compat20 && len > 0) {
1338: c->local_consumed += len;
1339: }
1340: }
1341: return 1;
1342: }
1.127 itojun 1343: static int
1.44 markus 1344: channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1345: {
1346: char buf[16*1024];
1347: int len;
1348:
1.45 markus 1349: /** XXX handle drain efd, too */
1.44 markus 1350: if (c->efd != -1) {
1351: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1352: FD_ISSET(c->efd, writeset) &&
1353: buffer_len(&c->extended) > 0) {
1354: len = write(c->efd, buffer_ptr(&c->extended),
1355: buffer_len(&c->extended));
1.70 markus 1356: debug2("channel %d: written %d to efd %d",
1.44 markus 1357: c->self, len, c->efd);
1.93 markus 1358: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1359: return 1;
1360: if (len <= 0) {
1361: debug2("channel %d: closing write-efd %d",
1362: c->self, c->efd);
1.132 markus 1363: channel_close_fd(&c->efd);
1.93 markus 1364: } else {
1.44 markus 1365: buffer_consume(&c->extended, len);
1366: c->local_consumed += len;
1367: }
1368: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1369: FD_ISSET(c->efd, readset)) {
1370: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1371: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1372: c->self, len, c->efd);
1.93 markus 1373: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1374: return 1;
1375: if (len <= 0) {
1376: debug2("channel %d: closing read-efd %d",
1.45 markus 1377: c->self, c->efd);
1.132 markus 1378: channel_close_fd(&c->efd);
1.93 markus 1379: } else {
1.44 markus 1380: buffer_append(&c->extended, buf, len);
1.93 markus 1381: }
1.44 markus 1382: }
1383: }
1384: return 1;
1385: }
1.127 itojun 1386: static int
1.93 markus 1387: channel_check_window(Channel *c)
1.44 markus 1388: {
1.104 markus 1389: if (c->type == SSH_CHANNEL_OPEN &&
1390: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.44 markus 1391: c->local_window < c->local_window_max/2 &&
1392: c->local_consumed > 0) {
1393: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1394: packet_put_int(c->remote_id);
1395: packet_put_int(c->local_consumed);
1396: packet_send();
1.70 markus 1397: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1398: c->self, c->local_window,
1399: c->local_consumed);
1400: c->local_window += c->local_consumed;
1401: c->local_consumed = 0;
1.1 deraadt 1402: }
1.41 markus 1403: return 1;
1.1 deraadt 1404: }
1405:
1.127 itojun 1406: static void
1.157 markus 1407: channel_post_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 1408: {
1.137 markus 1409: if (c->delayed)
1410: return;
1.41 markus 1411: channel_handle_rfd(c, readset, writeset);
1412: channel_handle_wfd(c, readset, writeset);
1.157 markus 1413: if (!compat20)
1.137 markus 1414: return;
1.44 markus 1415: channel_handle_efd(c, readset, writeset);
1.93 markus 1416: channel_check_window(c);
1.44 markus 1417: }
1418:
1.127 itojun 1419: static void
1.41 markus 1420: channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1.1 deraadt 1421: {
1.41 markus 1422: int len;
1423: /* Send buffered output data to the socket. */
1424: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1425: len = write(c->sock, buffer_ptr(&c->output),
1426: buffer_len(&c->output));
1427: if (len <= 0)
1.158 ! markus 1428: buffer_clear(&c->output);
1.41 markus 1429: else
1430: buffer_consume(&c->output, len);
1431: }
1432: }
1.25 markus 1433:
1.127 itojun 1434: static void
1.44 markus 1435: channel_handler_init_20(void)
1436: {
1.157 markus 1437: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1438: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1439: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1440: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1441: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1442: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1443: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1444: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1445:
1.157 markus 1446: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1447: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1448: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1449: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1450: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1451: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1452: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1453: }
1454:
1.127 itojun 1455: static void
1.41 markus 1456: channel_handler_init_13(void)
1457: {
1458: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1459: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1460: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1461: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1462: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1463: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1464: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1465: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1466: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1467:
1.157 markus 1468: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1469: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1470: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1471: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1472: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1473: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1474: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1475: }
1.25 markus 1476:
1.127 itojun 1477: static void
1.41 markus 1478: channel_handler_init_15(void)
1479: {
1.157 markus 1480: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1481: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1482: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1483: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1484: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1485: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1486: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1487:
1.41 markus 1488: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1489: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1490: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1491: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1492: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1493: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1494: }
1.27 markus 1495:
1.127 itojun 1496: static void
1.41 markus 1497: channel_handler_init(void)
1498: {
1499: int i;
1.148 deraadt 1500: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1501: channel_pre[i] = NULL;
1502: channel_post[i] = NULL;
1503: }
1.44 markus 1504: if (compat20)
1505: channel_handler_init_20();
1506: else if (compat13)
1.41 markus 1507: channel_handler_init_13();
1508: else
1509: channel_handler_init_15();
1510: }
1.25 markus 1511:
1.140 markus 1512: /* gc dead channels */
1513: static void
1514: channel_garbage_collect(Channel *c)
1515: {
1516: if (c == NULL)
1517: return;
1518: if (c->detach_user != NULL) {
1519: if (!chan_is_dead(c, 0))
1520: return;
1521: debug("channel %d: gc: notify user", c->self);
1522: c->detach_user(c->self, NULL);
1523: /* if we still have a callback */
1524: if (c->detach_user != NULL)
1525: return;
1526: debug("channel %d: gc: user detached", c->self);
1527: }
1528: if (!chan_is_dead(c, 1))
1529: return;
1530: debug("channel %d: garbage collecting", c->self);
1531: channel_free(c);
1532: }
1533:
1.127 itojun 1534: static void
1.41 markus 1535: channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1536: {
1537: static int did_init = 0;
1538: int i;
1539: Channel *c;
1.25 markus 1540:
1.41 markus 1541: if (!did_init) {
1542: channel_handler_init();
1543: did_init = 1;
1544: }
1545: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1546: c = channels[i];
1547: if (c == NULL)
1.41 markus 1548: continue;
1.118 markus 1549: if (ftab[c->type] != NULL)
1550: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1551: channel_garbage_collect(c);
1.1 deraadt 1552: }
1553: }
1554:
1.121 markus 1555: /*
1556: * Allocate/update select bitmasks and add any bits relevant to channels in
1557: * select bitmasks.
1558: */
1.49 markus 1559: void
1.100 markus 1560: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.132 markus 1561: int *nallocp, int rekeying)
1.41 markus 1562: {
1.84 markus 1563: int n;
1564: u_int sz;
1565:
1566: n = MAX(*maxfdp, channel_max_fd);
1567:
1568: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.132 markus 1569: /* perhaps check sz < nalloc/2 and shrink? */
1570: if (*readsetp == NULL || sz > *nallocp) {
1571: *readsetp = xrealloc(*readsetp, sz);
1572: *writesetp = xrealloc(*writesetp, sz);
1573: *nallocp = sz;
1.84 markus 1574: }
1.132 markus 1575: *maxfdp = n;
1.84 markus 1576: memset(*readsetp, 0, sz);
1577: memset(*writesetp, 0, sz);
1578:
1.100 markus 1579: if (!rekeying)
1580: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1581: }
1582:
1.121 markus 1583: /*
1584: * After select, perform any appropriate operations for channels which have
1585: * events pending.
1586: */
1.49 markus 1587: void
1.41 markus 1588: channel_after_select(fd_set * readset, fd_set * writeset)
1589: {
1590: channel_handler(channel_post, readset, writeset);
1591: }
1592:
1.121 markus 1593:
1.84 markus 1594: /* If there is data to send to the connection, enqueue some of it now. */
1.1 deraadt 1595:
1.49 markus 1596: void
1.142 itojun 1597: channel_output_poll(void)
1.1 deraadt 1598: {
1.25 markus 1599: int len, i;
1.41 markus 1600: Channel *c;
1.1 deraadt 1601:
1.25 markus 1602: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1603: c = channels[i];
1604: if (c == NULL)
1605: continue;
1.37 markus 1606:
1.121 markus 1607: /*
1608: * We are only interested in channels that can have buffered
1609: * incoming data.
1610: */
1.37 markus 1611: if (compat13) {
1.41 markus 1612: if (c->type != SSH_CHANNEL_OPEN &&
1613: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1614: continue;
1615: } else {
1.41 markus 1616: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1617: continue;
1618: }
1.46 markus 1619: if (compat20 &&
1620: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1621: /* XXX is this true? */
1.140 markus 1622: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1623: continue;
1624: }
1.25 markus 1625:
1626: /* Get the amount of buffered data for this channel. */
1.93 markus 1627: if ((c->istate == CHAN_INPUT_OPEN ||
1628: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1629: (len = buffer_len(&c->input)) > 0) {
1.121 markus 1630: /*
1631: * Send some data for the other side over the secure
1632: * connection.
1633: */
1.44 markus 1634: if (compat20) {
1635: if (len > c->remote_window)
1636: len = c->remote_window;
1637: if (len > c->remote_maxpacket)
1638: len = c->remote_maxpacket;
1.25 markus 1639: } else {
1.44 markus 1640: if (packet_is_interactive()) {
1641: if (len > 1024)
1642: len = 512;
1643: } else {
1644: /* Keep the packets at reasonable size. */
1645: if (len > packet_get_maxsize()/2)
1646: len = packet_get_maxsize()/2;
1647: }
1.25 markus 1648: }
1.41 markus 1649: if (len > 0) {
1.44 markus 1650: packet_start(compat20 ?
1651: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1652: packet_put_int(c->remote_id);
1653: packet_put_string(buffer_ptr(&c->input), len);
1654: packet_send();
1655: buffer_consume(&c->input, len);
1656: c->remote_window -= len;
1657: }
1658: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1659: if (compat13)
1660: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1661: /*
1662: * input-buffer is empty and read-socket shutdown:
1663: * tell peer, that we will not send more data: send IEOF
1664: */
1.41 markus 1665: chan_ibuf_empty(c);
1.25 markus 1666: }
1.44 markus 1667: /* Send extended data, i.e. stderr */
1668: if (compat20 &&
1669: c->remote_window > 0 &&
1670: (len = buffer_len(&c->extended)) > 0 &&
1671: c->extended_usage == CHAN_EXTENDED_READ) {
1.93 markus 1672: debug2("channel %d: rwin %d elen %d euse %d",
1673: c->self, c->remote_window, buffer_len(&c->extended),
1674: c->extended_usage);
1.44 markus 1675: if (len > c->remote_window)
1676: len = c->remote_window;
1677: if (len > c->remote_maxpacket)
1678: len = c->remote_maxpacket;
1679: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1680: packet_put_int(c->remote_id);
1681: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1682: packet_put_string(buffer_ptr(&c->extended), len);
1683: packet_send();
1684: buffer_consume(&c->extended, len);
1685: c->remote_window -= len;
1.93 markus 1686: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1687: }
1.25 markus 1688: }
1.1 deraadt 1689: }
1690:
1.121 markus 1691:
1692: /* -- protocol input */
1.1 deraadt 1693:
1.49 markus 1694: void
1.154 markus 1695: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1696: {
1.37 markus 1697: int id;
1.25 markus 1698: char *data;
1.77 markus 1699: u_int data_len;
1.41 markus 1700: Channel *c;
1.25 markus 1701:
1702: /* Get the channel number and verify it. */
1.37 markus 1703: id = packet_get_int();
1.41 markus 1704: c = channel_lookup(id);
1705: if (c == NULL)
1.37 markus 1706: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 1707:
1708: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 1709: if (c->type != SSH_CHANNEL_OPEN &&
1710: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 1711: return;
1712:
1713: /* same for protocol 1.5 if output end is no longer open */
1.41 markus 1714: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
1.25 markus 1715: return;
1716:
1717: /* Get the data. */
1718: data = packet_get_string(&data_len);
1.41 markus 1719:
1.143 deraadt 1720: if (compat20) {
1.44 markus 1721: if (data_len > c->local_maxpacket) {
1722: log("channel %d: rcvd big packet %d, maxpack %d",
1723: c->self, data_len, c->local_maxpacket);
1724: }
1725: if (data_len > c->local_window) {
1726: log("channel %d: rcvd too much data %d, win %d",
1727: c->self, data_len, c->local_window);
1728: xfree(data);
1729: return;
1730: }
1731: c->local_window -= data_len;
1732: }
1.152 markus 1733: packet_check_eom();
1.41 markus 1734: buffer_append(&c->output, data, data_len);
1.25 markus 1735: xfree(data);
1.1 deraadt 1736: }
1.121 markus 1737:
1.49 markus 1738: void
1.154 markus 1739: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 1740: {
1741: int id;
1742: int tcode;
1743: char *data;
1.77 markus 1744: u_int data_len;
1.44 markus 1745: Channel *c;
1746:
1747: /* Get the channel number and verify it. */
1748: id = packet_get_int();
1749: c = channel_lookup(id);
1750:
1751: if (c == NULL)
1752: packet_disconnect("Received extended_data for bad channel %d.", id);
1753: if (c->type != SSH_CHANNEL_OPEN) {
1754: log("channel %d: ext data for non open", id);
1755: return;
1756: }
1757: tcode = packet_get_int();
1758: if (c->efd == -1 ||
1759: c->extended_usage != CHAN_EXTENDED_WRITE ||
1760: tcode != SSH2_EXTENDED_DATA_STDERR) {
1761: log("channel %d: bad ext data", c->self);
1762: return;
1763: }
1764: data = packet_get_string(&data_len);
1.152 markus 1765: packet_check_eom();
1.44 markus 1766: if (data_len > c->local_window) {
1767: log("channel %d: rcvd too much extended_data %d, win %d",
1768: c->self, data_len, c->local_window);
1769: xfree(data);
1770: return;
1771: }
1.70 markus 1772: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 1773: c->local_window -= data_len;
1774: buffer_append(&c->extended, data, data_len);
1775: xfree(data);
1776: }
1777:
1.49 markus 1778: void
1.154 markus 1779: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 1780: {
1781: int id;
1782: Channel *c;
1783:
1784: id = packet_get_int();
1.152 markus 1785: packet_check_eom();
1.41 markus 1786: c = channel_lookup(id);
1787: if (c == NULL)
1788: packet_disconnect("Received ieof for nonexistent channel %d.", id);
1789: chan_rcvd_ieof(c);
1.133 markus 1790:
1791: /* XXX force input close */
1.156 markus 1792: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 1793: debug("channel %d: FORCE input drain", c->self);
1794: c->istate = CHAN_INPUT_WAIT_DRAIN;
1795: }
1796:
1.41 markus 1797: }
1.1 deraadt 1798:
1.49 markus 1799: void
1.154 markus 1800: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1801: {
1.41 markus 1802: int id;
1803: Channel *c;
1.1 deraadt 1804:
1.41 markus 1805: id = packet_get_int();
1.152 markus 1806: packet_check_eom();
1.41 markus 1807: c = channel_lookup(id);
1808: if (c == NULL)
1809: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 1810:
1811: /*
1812: * Send a confirmation that we have closed the channel and no more
1813: * data is coming for it.
1814: */
1.25 markus 1815: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 1816: packet_put_int(c->remote_id);
1.25 markus 1817: packet_send();
1818:
1.27 markus 1819: /*
1820: * If the channel is in closed state, we have sent a close request,
1821: * and the other side will eventually respond with a confirmation.
1822: * Thus, we cannot free the channel here, because then there would be
1823: * no-one to receive the confirmation. The channel gets freed when
1824: * the confirmation arrives.
1825: */
1.41 markus 1826: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 1827: /*
1828: * Not a closed channel - mark it as draining, which will
1829: * cause it to be freed later.
1830: */
1.158 ! markus 1831: buffer_clear(&c->input);
1.41 markus 1832: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 1833: }
1.1 deraadt 1834: }
1835:
1.41 markus 1836: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.49 markus 1837: void
1.154 markus 1838: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 1839: {
1840: int id = packet_get_int();
1841: Channel *c = channel_lookup(id);
1.151 markus 1842:
1.152 markus 1843: packet_check_eom();
1.41 markus 1844: if (c == NULL)
1845: packet_disconnect("Received oclose for nonexistent channel %d.", id);
1846: chan_rcvd_oclose(c);
1847: }
1.1 deraadt 1848:
1.49 markus 1849: void
1.154 markus 1850: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1851: {
1.41 markus 1852: int id = packet_get_int();
1853: Channel *c = channel_lookup(id);
1.1 deraadt 1854:
1.152 markus 1855: packet_check_eom();
1.41 markus 1856: if (c == NULL)
1857: packet_disconnect("Received close confirmation for "
1858: "out-of-range channel %d.", id);
1859: if (c->type != SSH_CHANNEL_CLOSED)
1860: packet_disconnect("Received close confirmation for "
1861: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 1862: channel_free(c);
1.1 deraadt 1863: }
1864:
1.49 markus 1865: void
1.154 markus 1866: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1867: {
1.41 markus 1868: int id, remote_id;
1869: Channel *c;
1.1 deraadt 1870:
1.41 markus 1871: id = packet_get_int();
1872: c = channel_lookup(id);
1.25 markus 1873:
1.41 markus 1874: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1875: packet_disconnect("Received open confirmation for "
1876: "non-opening channel %d.", id);
1877: remote_id = packet_get_int();
1.27 markus 1878: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 1879: c->remote_id = remote_id;
1880: c->type = SSH_CHANNEL_OPEN;
1.44 markus 1881:
1882: if (compat20) {
1883: c->remote_window = packet_get_int();
1884: c->remote_maxpacket = packet_get_int();
1885: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1886: debug2("callback start");
1.44 markus 1887: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1888: debug2("callback done");
1.44 markus 1889: }
1890: debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1891: c->remote_window, c->remote_maxpacket);
1892: }
1.152 markus 1893: packet_check_eom();
1.1 deraadt 1894: }
1895:
1.127 itojun 1896: static char *
1.114 markus 1897: reason2txt(int reason)
1898: {
1.143 deraadt 1899: switch (reason) {
1.114 markus 1900: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1901: return "administratively prohibited";
1902: case SSH2_OPEN_CONNECT_FAILED:
1903: return "connect failed";
1904: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1905: return "unknown channel type";
1906: case SSH2_OPEN_RESOURCE_SHORTAGE:
1907: return "resource shortage";
1908: }
1.117 stevesk 1909: return "unknown reason";
1.114 markus 1910: }
1911:
1.49 markus 1912: void
1.154 markus 1913: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1914: {
1.86 markus 1915: int id, reason;
1916: char *msg = NULL, *lang = NULL;
1.41 markus 1917: Channel *c;
1918:
1919: id = packet_get_int();
1920: c = channel_lookup(id);
1.25 markus 1921:
1.41 markus 1922: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1923: packet_disconnect("Received open failure for "
1924: "non-opening channel %d.", id);
1.44 markus 1925: if (compat20) {
1.86 markus 1926: reason = packet_get_int();
1.110 markus 1927: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 1928: msg = packet_get_string(NULL);
1929: lang = packet_get_string(NULL);
1930: }
1.114 markus 1931: log("channel %d: open failed: %s%s%s", id,
1932: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 1933: if (msg != NULL)
1934: xfree(msg);
1935: if (lang != NULL)
1936: xfree(lang);
1.44 markus 1937: }
1.152 markus 1938: packet_check_eom();
1.25 markus 1939: /* Free the channel. This will also close the socket. */
1.113 markus 1940: channel_free(c);
1.1 deraadt 1941: }
1942:
1.44 markus 1943: void
1.154 markus 1944: channel_input_channel_request(int type, u_int32_t seq, void *ctxt)
1.44 markus 1945: {
1946: int id;
1947: Channel *c;
1948:
1949: id = packet_get_int();
1950: c = channel_lookup(id);
1951:
1952: if (c == NULL ||
1953: (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1954: packet_disconnect("Received request for "
1955: "non-open channel %d.", id);
1956: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1957: debug2("callback start");
1.44 markus 1958: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1959: debug2("callback done");
1.44 markus 1960: } else {
1961: char *service = packet_get_string(NULL);
1.94 markus 1962: debug("channel %d: rcvd request for %s", c->self, service);
1.70 markus 1963: debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
1.44 markus 1964: xfree(service);
1965: }
1966: }
1967:
1.121 markus 1968: void
1.154 markus 1969: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 1970: {
1971: Channel *c;
1972: int id, adjust;
1973:
1974: if (!compat20)
1975: return;
1976:
1977: /* Get the channel number and verify it. */
1978: id = packet_get_int();
1979: c = channel_lookup(id);
1.1 deraadt 1980:
1.121 markus 1981: if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
1982: log("Received window adjust for "
1983: "non-open channel %d.", id);
1984: return;
1985: }
1986: adjust = packet_get_int();
1.152 markus 1987: packet_check_eom();
1.121 markus 1988: debug2("channel %d: rcvd adjust %d", id, adjust);
1989: c->remote_window += adjust;
1990: }
1.1 deraadt 1991:
1.121 markus 1992: void
1.154 markus 1993: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1994: {
1.121 markus 1995: Channel *c = NULL;
1996: u_short host_port;
1997: char *host, *originator_string;
1998: int remote_id, sock = -1;
1999:
2000: remote_id = packet_get_int();
2001: host = packet_get_string(NULL);
2002: host_port = packet_get_int();
1.25 markus 2003:
1.121 markus 2004: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2005: originator_string = packet_get_string(NULL);
2006: } else {
2007: originator_string = xstrdup("unknown (remote did not supply name)");
2008: }
1.152 markus 2009: packet_check_eom();
1.121 markus 2010: sock = channel_connect_to(host, host_port);
2011: if (sock != -1) {
2012: c = channel_new("connected socket",
2013: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2014: originator_string, 1);
2015: if (c == NULL) {
2016: error("channel_input_port_open: channel_new failed");
2017: close(sock);
2018: } else {
2019: c->remote_id = remote_id;
1.25 markus 2020: }
2021: }
1.121 markus 2022: if (c == NULL) {
2023: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2024: packet_put_int(remote_id);
2025: packet_send();
2026: }
2027: xfree(host);
1.1 deraadt 2028: }
2029:
1.121 markus 2030:
2031: /* -- tcp forwarding */
1.135 markus 2032:
2033: void
2034: channel_set_af(int af)
2035: {
2036: IPv4or6 = af;
2037: }
1.121 markus 2038:
1.27 markus 2039: /*
2040: * Initiate forwarding of connections to local port "port" through the secure
2041: * channel to host:port from remote side.
2042: */
1.87 markus 2043: int
1.73 markus 2044: channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
2045: u_short port_to_connect, int gateway_ports)
2046: {
1.87 markus 2047: return channel_request_forwarding(
1.73 markus 2048: NULL, listen_port,
2049: host_to_connect, port_to_connect,
2050: gateway_ports, /*remote_fwd*/ 0);
2051: }
1.1 deraadt 2052:
1.73 markus 2053: /*
2054: * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
2055: * (SSH_CHANNEL_RPORT_LISTENER).
2056: */
1.87 markus 2057: int
1.73 markus 2058: channel_request_forwarding(
2059: const char *listen_address, u_short listen_port,
2060: const char *host_to_connect, u_short port_to_connect,
2061: int gateway_ports, int remote_fwd)
1.25 markus 2062: {
1.113 markus 2063: Channel *c;
1.121 markus 2064: int success, sock, on = 1, type;
1.35 markus 2065: struct addrinfo hints, *ai, *aitop;
2066: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.73 markus 2067: const char *host;
1.28 markus 2068: struct linger linger;
1.25 markus 2069:
1.87 markus 2070: success = 0;
2071:
1.73 markus 2072: if (remote_fwd) {
2073: host = listen_address;
1.121 markus 2074: type = SSH_CHANNEL_RPORT_LISTENER;
1.73 markus 2075: } else {
2076: host = host_to_connect;
1.121 markus 2077: type = SSH_CHANNEL_PORT_LISTENER;
1.73 markus 2078: }
2079:
1.113 markus 2080: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2081: error("Forward host name too long.");
2082: return success;
2083: }
1.25 markus 2084:
1.73 markus 2085: /* XXX listen_address is currently ignored */
1.28 markus 2086: /*
1.35 markus 2087: * getaddrinfo returns a loopback address if the hostname is
2088: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2089: */
1.35 markus 2090: memset(&hints, 0, sizeof(hints));
2091: hints.ai_family = IPv4or6;
2092: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2093: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2094: snprintf(strport, sizeof strport, "%d", listen_port);
1.35 markus 2095: if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2096: packet_disconnect("getaddrinfo: fatal error");
2097:
2098: for (ai = aitop; ai; ai = ai->ai_next) {
2099: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2100: continue;
2101: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2102: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.73 markus 2103: error("channel_request_forwarding: getnameinfo failed");
1.35 markus 2104: continue;
2105: }
2106: /* Create a port to listen for the host. */
2107: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2108: if (sock < 0) {
2109: /* this is no error since kernel may not support ipv6 */
2110: verbose("socket: %.100s", strerror(errno));
2111: continue;
2112: }
2113: /*
2114: * Set socket options. We would like the socket to disappear
2115: * as soon as it has been closed for whatever reason.
2116: */
2117: setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
2118: linger.l_onoff = 1;
2119: linger.l_linger = 5;
2120: setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
2121: debug("Local forwarding listening on %s port %s.", ntop, strport);
2122:
2123: /* Bind the socket to the address. */
2124: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2125: /* address can be in use ipv6 address is already bound */
2126: verbose("bind: %.100s", strerror(errno));
2127: close(sock);
2128: continue;
2129: }
2130: /* Start listening for connections on the socket. */
2131: if (listen(sock, 5) < 0) {
2132: error("listen: %.100s", strerror(errno));
2133: close(sock);
2134: continue;
2135: }
2136: /* Allocate a channel number for the socket. */
1.121 markus 2137: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2138: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.71 markus 2139: 0, xstrdup("port listener"), 1);
1.113 markus 2140: if (c == NULL) {
2141: error("channel_request_forwarding: channel_new failed");
2142: close(sock);
2143: continue;
2144: }
2145: strlcpy(c->path, host, sizeof(c->path));
2146: c->host_port = port_to_connect;
2147: c->listening_port = listen_port;
1.35 markus 2148: success = 1;
2149: }
2150: if (success == 0)
1.87 markus 2151: error("channel_request_forwarding: cannot listen to port: %d",
2152: listen_port);
1.35 markus 2153: freeaddrinfo(aitop);
1.87 markus 2154: return success;
1.25 markus 2155: }
1.1 deraadt 2156:
1.27 markus 2157: /*
2158: * Initiate forwarding of connections to port "port" on remote host through
2159: * the secure channel to host:port from local side.
2160: */
1.1 deraadt 2161:
1.49 markus 2162: void
1.73 markus 2163: channel_request_remote_forwarding(u_short listen_port,
2164: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2165: {
1.153 markus 2166: int type, success = 0;
1.73 markus 2167:
1.25 markus 2168: /* Record locally that connection to this host/port is permitted. */
2169: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2170: fatal("channel_request_remote_forwarding: too many forwards");
2171:
2172: /* Send the forward request to the remote side. */
1.44 markus 2173: if (compat20) {
2174: const char *address_to_bind = "0.0.0.0";
2175: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2176: packet_put_cstring("tcpip-forward");
2177: packet_put_char(0); /* boolean: want reply */
2178: packet_put_cstring(address_to_bind);
2179: packet_put_int(listen_port);
1.73 markus 2180: packet_send();
2181: packet_write_wait();
2182: /* Assume that server accepts the request */
2183: success = 1;
1.44 markus 2184: } else {
2185: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2186: packet_put_int(listen_port);
2187: packet_put_cstring(host_to_connect);
1.44 markus 2188: packet_put_int(port_to_connect);
2189: packet_send();
2190: packet_write_wait();
1.73 markus 2191:
2192: /* Wait for response from the remote side. */
1.153 markus 2193: type = packet_read();
1.73 markus 2194: switch (type) {
2195: case SSH_SMSG_SUCCESS:
2196: success = 1;
2197: break;
2198: case SSH_SMSG_FAILURE:
2199: log("Warning: Server denied remote port forwarding.");
2200: break;
2201: default:
2202: /* Unknown packet */
2203: packet_disconnect("Protocol error for port forward request:"
2204: "received packet type %d.", type);
2205: }
2206: }
2207: if (success) {
2208: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2209: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2210: permitted_opens[num_permitted_opens].listen_port = listen_port;
2211: num_permitted_opens++;
1.44 markus 2212: }
1.1 deraadt 2213: }
2214:
1.27 markus 2215: /*
2216: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2217: * listening for the port, and sends back a success reply (or disconnect
2218: * message if there was an error). This never returns if there was an error.
2219: */
1.1 deraadt 2220:
1.49 markus 2221: void
1.56 markus 2222: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2223: {
1.31 markus 2224: u_short port, host_port;
1.25 markus 2225: char *hostname;
1.1 deraadt 2226:
1.25 markus 2227: /* Get arguments from the packet. */
2228: port = packet_get_int();
2229: hostname = packet_get_string(NULL);
2230: host_port = packet_get_int();
2231:
1.27 markus 2232: /*
2233: * Check that an unprivileged user is not trying to forward a
2234: * privileged port.
2235: */
1.25 markus 2236: if (port < IPPORT_RESERVED && !is_root)
2237: packet_disconnect("Requested forwarding of port %d but user is not root.",
2238: port);
1.73 markus 2239: /* Initiate forwarding */
1.56 markus 2240: channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
1.25 markus 2241:
2242: /* Free the argument string. */
2243: xfree(hostname);
1.1 deraadt 2244: }
2245:
1.99 markus 2246: /*
2247: * Permits opening to any host/port if permitted_opens[] is empty. This is
2248: * usually called by the server, because the user could connect to any port
2249: * anyway, and the server has no way to know but to trust the client anyway.
2250: */
2251: void
1.142 itojun 2252: channel_permit_all_opens(void)
1.99 markus 2253: {
2254: if (num_permitted_opens == 0)
2255: all_opens_permitted = 1;
2256: }
2257:
1.101 markus 2258: void
1.99 markus 2259: channel_add_permitted_opens(char *host, int port)
2260: {
2261: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2262: fatal("channel_request_remote_forwarding: too many forwards");
2263: debug("allow port forwarding to host %s port %d", host, port);
2264:
2265: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2266: permitted_opens[num_permitted_opens].port_to_connect = port;
2267: num_permitted_opens++;
2268:
2269: all_opens_permitted = 0;
2270: }
2271:
1.101 markus 2272: void
1.99 markus 2273: channel_clear_permitted_opens(void)
2274: {
2275: int i;
2276:
2277: for (i = 0; i < num_permitted_opens; i++)
2278: xfree(permitted_opens[i].host_to_connect);
2279: num_permitted_opens = 0;
2280:
2281: }
2282:
2283:
2284: /* return socket to remote host, port */
1.127 itojun 2285: static int
1.99 markus 2286: connect_to(const char *host, u_short port)
1.41 markus 2287: {
2288: struct addrinfo hints, *ai, *aitop;
2289: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2290: int gaierr;
2291: int sock = -1;
2292:
2293: memset(&hints, 0, sizeof(hints));
2294: hints.ai_family = IPv4or6;
2295: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2296: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2297: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2298: error("connect_to %.100s: unknown host (%s)", host,
2299: gai_strerror(gaierr));
1.41 markus 2300: return -1;
2301: }
2302: for (ai = aitop; ai; ai = ai->ai_next) {
2303: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2304: continue;
2305: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2306: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2307: error("connect_to: getnameinfo failed");
1.41 markus 2308: continue;
2309: }
2310: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2311: if (sock < 0) {
2312: error("socket: %.100s", strerror(errno));
2313: continue;
2314: }
1.80 markus 2315: if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
1.75 markus 2316: fatal("connect_to: F_SETFL: %s", strerror(errno));
2317: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2318: errno != EINPROGRESS) {
1.99 markus 2319: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2320: strerror(errno));
2321: close(sock);
1.89 stevesk 2322: continue; /* fail -- try next */
1.41 markus 2323: }
2324: break; /* success */
2325:
2326: }
2327: freeaddrinfo(aitop);
2328: if (!ai) {
1.99 markus 2329: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2330: return -1;
2331: }
2332: /* success */
2333: return sock;
2334: }
1.99 markus 2335:
1.73 markus 2336: int
1.130 stevesk 2337: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2338: {
2339: int i;
1.99 markus 2340:
1.73 markus 2341: for (i = 0; i < num_permitted_opens; i++)
2342: if (permitted_opens[i].listen_port == listen_port)
1.99 markus 2343: return connect_to(
1.73 markus 2344: permitted_opens[i].host_to_connect,
2345: permitted_opens[i].port_to_connect);
1.74 markus 2346: error("WARNING: Server requests forwarding for unknown listen_port %d",
2347: listen_port);
1.73 markus 2348: return -1;
2349: }
2350:
1.99 markus 2351: /* Check if connecting to that port is permitted and connect. */
2352: int
2353: channel_connect_to(const char *host, u_short port)
2354: {
2355: int i, permit;
2356:
2357: permit = all_opens_permitted;
2358: if (!permit) {
2359: for (i = 0; i < num_permitted_opens; i++)
2360: if (permitted_opens[i].port_to_connect == port &&
2361: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2362: permit = 1;
2363:
2364: }
2365: if (!permit) {
2366: log("Received request to connect to host %.100s port %d, "
2367: "but the request was denied.", host, port);
2368: return -1;
2369: }
2370: return connect_to(host, port);
2371: }
2372:
1.121 markus 2373: /* -- X11 forwarding */
1.1 deraadt 2374:
1.27 markus 2375: /*
2376: * Creates an internet domain socket for listening for X11 connections.
1.141 stevesk 2377: * Returns a suitable display number for the DISPLAY variable, or -1 if
2378: * an error occurs.
1.27 markus 2379: */
1.141 stevesk 2380: int
1.149 markus 2381: x11_create_display_inet(int x11_display_offset, int gateway_ports,
2382: int single_connection)
1.1 deraadt 2383: {
1.149 markus 2384: Channel *nc = NULL;
1.31 markus 2385: int display_number, sock;
2386: u_short port;
1.35 markus 2387: struct addrinfo hints, *ai, *aitop;
2388: char strport[NI_MAXSERV];
2389: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 2390:
1.33 markus 2391: for (display_number = x11_display_offset;
1.148 deraadt 2392: display_number < MAX_DISPLAYS;
2393: display_number++) {
1.25 markus 2394: port = 6000 + display_number;
1.35 markus 2395: memset(&hints, 0, sizeof(hints));
2396: hints.ai_family = IPv4or6;
1.141 stevesk 2397: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
1.35 markus 2398: hints.ai_socktype = SOCK_STREAM;
2399: snprintf(strport, sizeof strport, "%d", port);
2400: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2401: error("getaddrinfo: %.100s", gai_strerror(gaierr));
1.141 stevesk 2402: return -1;
1.25 markus 2403: }
1.35 markus 2404: for (ai = aitop; ai; ai = ai->ai_next) {
2405: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2406: continue;
2407: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2408: if (sock < 0) {
2409: error("socket: %.100s", strerror(errno));
1.141 stevesk 2410: return -1;
1.35 markus 2411: }
2412: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2413: debug("bind port %d: %.100s", port, strerror(errno));
2414: close(sock);
2415: for (n = 0; n < num_socks; n++) {
2416: close(socks[n]);
2417: }
2418: num_socks = 0;
2419: break;
2420: }
2421: socks[num_socks++] = sock;
2422: if (num_socks == NUM_SOCKS)
2423: break;
1.25 markus 2424: }
1.83 stevesk 2425: freeaddrinfo(aitop);
1.35 markus 2426: if (num_socks > 0)
2427: break;
1.25 markus 2428: }
2429: if (display_number >= MAX_DISPLAYS) {
2430: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 2431: return -1;
1.25 markus 2432: }
2433: /* Start listening for connections on the socket. */
1.35 markus 2434: for (n = 0; n < num_socks; n++) {
2435: sock = socks[n];
2436: if (listen(sock, 5) < 0) {
2437: error("listen: %.100s", strerror(errno));
2438: close(sock);
1.141 stevesk 2439: return -1;
1.35 markus 2440: }
1.25 markus 2441: }
1.35 markus 2442:
2443: /* Allocate a channel for each socket. */
2444: for (n = 0; n < num_socks; n++) {
2445: sock = socks[n];
1.149 markus 2446: nc = channel_new("x11 listener",
1.51 markus 2447: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2448: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.71 markus 2449: 0, xstrdup("X11 inet listener"), 1);
1.149 markus 2450: if (nc != NULL)
2451: nc->single_connection = single_connection;
1.35 markus 2452: }
1.1 deraadt 2453:
1.141 stevesk 2454: /* Return the display number for the DISPLAY environment variable. */
2455: return display_number;
1.1 deraadt 2456: }
2457:
1.127 itojun 2458: static int
1.77 markus 2459: connect_local_xsocket(u_int dnr)
1.1 deraadt 2460: {
1.25 markus 2461: int sock;
2462: struct sockaddr_un addr;
2463:
1.147 stevesk 2464: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2465: if (sock < 0)
2466: error("socket: %.100s", strerror(errno));
2467: memset(&addr, 0, sizeof(addr));
2468: addr.sun_family = AF_UNIX;
2469: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
2470: if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2471: return sock;
2472: close(sock);
1.25 markus 2473: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2474: return -1;
1.1 deraadt 2475: }
2476:
1.51 markus 2477: int
2478: x11_connect_display(void)
1.1 deraadt 2479: {
1.146 stevesk 2480: int display_number, sock = 0, on = 1;
1.25 markus 2481: const char *display;
1.51 markus 2482: char buf[1024], *cp;
1.35 markus 2483: struct addrinfo hints, *ai, *aitop;
2484: char strport[NI_MAXSERV];
2485: int gaierr;
1.25 markus 2486:
2487: /* Try to open a socket for the local X server. */
2488: display = getenv("DISPLAY");
2489: if (!display) {
2490: error("DISPLAY not set.");
1.51 markus 2491: return -1;
1.25 markus 2492: }
1.27 markus 2493: /*
2494: * Now we decode the value of the DISPLAY variable and make a
2495: * connection to the real X server.
2496: */
2497:
2498: /*
2499: * Check if it is a unix domain socket. Unix domain displays are in
2500: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2501: */
1.25 markus 2502: if (strncmp(display, "unix:", 5) == 0 ||
2503: display[0] == ':') {
2504: /* Connect to the unix domain socket. */
2505: if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2506: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2507: display);
1.51 markus 2508: return -1;
1.25 markus 2509: }
2510: /* Create a socket. */
2511: sock = connect_local_xsocket(display_number);
2512: if (sock < 0)
1.51 markus 2513: return -1;
1.25 markus 2514:
2515: /* OK, we now have a connection to the display. */
1.51 markus 2516: return sock;
1.25 markus 2517: }
1.27 markus 2518: /*
2519: * Connect to an inet socket. The DISPLAY value is supposedly
2520: * hostname:d[.s], where hostname may also be numeric IP address.
2521: */
1.145 stevesk 2522: strlcpy(buf, display, sizeof(buf));
1.25 markus 2523: cp = strchr(buf, ':');
2524: if (!cp) {
2525: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 2526: return -1;
1.25 markus 2527: }
2528: *cp = 0;
1.27 markus 2529: /* buf now contains the host name. But first we parse the display number. */
1.25 markus 2530: if (sscanf(cp + 1, "%d", &display_number) != 1) {
2531: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2532: display);
1.51 markus 2533: return -1;
1.25 markus 2534: }
1.35 markus 2535:
2536: /* Look up the host address */
2537: memset(&hints, 0, sizeof(hints));
2538: hints.ai_family = IPv4or6;
2539: hints.ai_socktype = SOCK_STREAM;
2540: snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2541: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2542: error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
1.51 markus 2543: return -1;
1.25 markus 2544: }
1.35 markus 2545: for (ai = aitop; ai; ai = ai->ai_next) {
2546: /* Create a socket. */
2547: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2548: if (sock < 0) {
2549: debug("socket: %.100s", strerror(errno));
1.41 markus 2550: continue;
2551: }
2552: /* Connect it to the display. */
2553: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2554: debug("connect %.100s port %d: %.100s", buf,
2555: 6000 + display_number, strerror(errno));
2556: close(sock);
2557: continue;
2558: }
2559: /* Success */
2560: break;
1.35 markus 2561: }
2562: freeaddrinfo(aitop);
2563: if (!ai) {
1.49 markus 2564: error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
1.35 markus 2565: strerror(errno));
1.51 markus 2566: return -1;
1.25 markus 2567: }
1.146 stevesk 2568: if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on) == -1)
2569: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
1.51 markus 2570: return sock;
2571: }
2572:
2573: /*
2574: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2575: * the remote channel number. We should do whatever we want, and respond
2576: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2577: */
2578:
2579: void
1.154 markus 2580: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 2581: {
1.113 markus 2582: Channel *c = NULL;
2583: int remote_id, sock = 0;
1.51 markus 2584: char *remote_host;
1.25 markus 2585:
1.113 markus 2586: debug("Received X11 open request.");
1.51 markus 2587:
1.113 markus 2588: remote_id = packet_get_int();
1.121 markus 2589:
2590: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 2591: remote_host = packet_get_string(NULL);
1.51 markus 2592: } else {
2593: remote_host = xstrdup("unknown (remote did not supply name)");
2594: }
1.152 markus 2595: packet_check_eom();
1.25 markus 2596:
1.51 markus 2597: /* Obtain a connection to the real X display. */
2598: sock = x11_connect_display();
1.113 markus 2599: if (sock != -1) {
2600: /* Allocate a channel for this connection. */
2601: c = channel_new("connected x11 socket",
2602: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2603: remote_host, 1);
2604: if (c == NULL) {
2605: error("x11_input_open: channel_new failed");
2606: close(sock);
2607: } else {
2608: c->remote_id = remote_id;
1.133 markus 2609: c->force_drain = 1;
1.113 markus 2610: }
2611: }
2612: if (c == NULL) {
1.51 markus 2613: /* Send refusal to the remote host. */
2614: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2615: packet_put_int(remote_id);
1.51 markus 2616: } else {
2617: /* Send a confirmation to the remote host. */
2618: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 2619: packet_put_int(remote_id);
2620: packet_put_int(c->self);
1.51 markus 2621: }
1.113 markus 2622: packet_send();
1.72 markus 2623: }
2624:
2625: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2626: void
1.154 markus 2627: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 2628: {
2629: int rchan = packet_get_int();
1.143 deraadt 2630: switch (type) {
1.72 markus 2631: case SSH_SMSG_AGENT_OPEN:
2632: error("Warning: ssh server tried agent forwarding.");
2633: break;
2634: case SSH_SMSG_X11_OPEN:
2635: error("Warning: ssh server tried X11 forwarding.");
2636: break;
2637: default:
1.154 markus 2638: error("deny_input_open: type %d", type);
1.72 markus 2639: break;
2640: }
2641: error("Warning: this is probably a break in attempt by a malicious server.");
2642: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2643: packet_put_int(rchan);
2644: packet_send();
1.1 deraadt 2645: }
2646:
1.27 markus 2647: /*
2648: * Requests forwarding of X11 connections, generates fake authentication
2649: * data, and enables authentication spoofing.
1.121 markus 2650: * This should be called in the client only.
1.27 markus 2651: */
1.49 markus 2652: void
1.51 markus 2653: x11_request_forwarding_with_spoofing(int client_session_id,
2654: const char *proto, const char *data)
1.1 deraadt 2655: {
1.77 markus 2656: u_int data_len = (u_int) strlen(data) / 2;
1.90 markus 2657: u_int i, value, len;
1.25 markus 2658: char *new_data;
2659: int screen_number;
2660: const char *cp;
2661: u_int32_t rand = 0;
2662:
2663: cp = getenv("DISPLAY");
2664: if (cp)
2665: cp = strchr(cp, ':');
2666: if (cp)
2667: cp = strchr(cp, '.');
2668: if (cp)
2669: screen_number = atoi(cp + 1);
2670: else
2671: screen_number = 0;
2672:
2673: /* Save protocol name. */
2674: x11_saved_proto = xstrdup(proto);
2675:
1.27 markus 2676: /*
2677: * Extract real authentication data and generate fake data of the
2678: * same length.
2679: */
1.25 markus 2680: x11_saved_data = xmalloc(data_len);
2681: x11_fake_data = xmalloc(data_len);
2682: for (i = 0; i < data_len; i++) {
2683: if (sscanf(data + 2 * i, "%2x", &value) != 1)
2684: fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2685: if (i % 4 == 0)
2686: rand = arc4random();
2687: x11_saved_data[i] = value;
2688: x11_fake_data[i] = rand & 0xff;
2689: rand >>= 8;
2690: }
2691: x11_saved_data_len = data_len;
2692: x11_fake_data_len = data_len;
2693:
2694: /* Convert the fake data into hex. */
1.90 markus 2695: len = 2 * data_len + 1;
2696: new_data = xmalloc(len);
1.25 markus 2697: for (i = 0; i < data_len; i++)
1.90 markus 2698: snprintf(new_data + 2 * i, len - 2 * i,
2699: "%02x", (u_char) x11_fake_data[i]);
1.25 markus 2700:
2701: /* Send the request packet. */
1.51 markus 2702: if (compat20) {
2703: channel_request_start(client_session_id, "x11-req", 0);
2704: packet_put_char(0); /* XXX bool single connection */
2705: } else {
2706: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2707: }
2708: packet_put_cstring(proto);
2709: packet_put_cstring(new_data);
1.25 markus 2710: packet_put_int(screen_number);
2711: packet_send();
2712: packet_write_wait();
2713: xfree(new_data);
1.1 deraadt 2714: }
2715:
1.121 markus 2716:
2717: /* -- agent forwarding */
2718:
1.1 deraadt 2719: /* Sends a message to the server to request authentication fd forwarding. */
2720:
1.49 markus 2721: void
1.142 itojun 2722: auth_request_forwarding(void)
1.1 deraadt 2723: {
1.25 markus 2724: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2725: packet_send();
2726: packet_write_wait();
1.1 deraadt 2727: }
2728:
1.27 markus 2729: /*
2730: * Returns the name of the forwarded authentication socket. Returns NULL if
2731: * there is no forwarded authentication socket. The returned value points to
2732: * a static buffer.
2733: */
1.1 deraadt 2734:
1.25 markus 2735: char *
1.142 itojun 2736: auth_get_socket_name(void)
1.1 deraadt 2737: {
1.121 markus 2738: return auth_sock_name;
1.1 deraadt 2739: }
2740:
1.12 markus 2741: /* removes the agent forwarding socket */
2742:
1.49 markus 2743: void
1.123 markus 2744: auth_sock_cleanup_proc(void *_pw)
1.25 markus 2745: {
1.123 markus 2746: struct passwd *pw = _pw;
2747:
1.122 markus 2748: if (auth_sock_name) {
1.123 markus 2749: temporarily_use_uid(pw);
1.122 markus 2750: unlink(auth_sock_name);
2751: rmdir(auth_sock_dir);
2752: auth_sock_name = NULL;
1.123 markus 2753: restore_uid();
1.122 markus 2754: }
1.12 markus 2755: }
2756:
1.27 markus 2757: /*
1.59 markus 2758: * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
1.27 markus 2759: * This starts forwarding authentication requests.
2760: */
1.1 deraadt 2761:
1.59 markus 2762: int
1.25 markus 2763: auth_input_request_forwarding(struct passwd * pw)
1.1 deraadt 2764: {
1.113 markus 2765: Channel *nc;
2766: int sock;
1.25 markus 2767: struct sockaddr_un sunaddr;
2768:
1.121 markus 2769: if (auth_get_socket_name() != NULL) {
2770: error("authentication forwarding requested twice.");
2771: return 0;
2772: }
1.25 markus 2773:
2774: /* Temporarily drop privileged uid for mkdir/bind. */
1.102 markus 2775: temporarily_use_uid(pw);
1.25 markus 2776:
2777: /* Allocate a buffer for the socket name, and format the name. */
1.121 markus 2778: auth_sock_name = xmalloc(MAXPATHLEN);
2779: auth_sock_dir = xmalloc(MAXPATHLEN);
2780: strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1.25 markus 2781:
2782: /* Create private directory for socket */
1.121 markus 2783: if (mkdtemp(auth_sock_dir) == NULL) {
2784: packet_send_debug("Agent forwarding disabled: "
2785: "mkdtemp() failed: %.100s", strerror(errno));
1.59 markus 2786: restore_uid();
1.121 markus 2787: xfree(auth_sock_name);
2788: xfree(auth_sock_dir);
2789: auth_sock_name = NULL;
2790: auth_sock_dir = NULL;
1.59 markus 2791: return 0;
2792: }
1.121 markus 2793: snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d",
2794: auth_sock_dir, (int) getpid());
1.25 markus 2795:
1.122 markus 2796: /* delete agent socket on fatal() */
1.123 markus 2797: fatal_add_cleanup(auth_sock_cleanup_proc, pw);
1.122 markus 2798:
1.25 markus 2799: /* Create the socket. */
2800: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2801: if (sock < 0)
2802: packet_disconnect("socket: %.100s", strerror(errno));
2803:
2804: /* Bind it to the name. */
2805: memset(&sunaddr, 0, sizeof(sunaddr));
2806: sunaddr.sun_family = AF_UNIX;
1.145 stevesk 2807: strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
1.25 markus 2808:
2809: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2810: packet_disconnect("bind: %.100s", strerror(errno));
2811:
2812: /* Restore the privileged uid. */
2813: restore_uid();
2814:
2815: /* Start listening on the socket. */
2816: if (listen(sock, 5) < 0)
2817: packet_disconnect("listen: %.100s", strerror(errno));
2818:
2819: /* Allocate a channel for the authentication agent socket. */
1.113 markus 2820: nc = channel_new("auth socket",
1.73 markus 2821: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2822: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2823: 0, xstrdup("auth socket"), 1);
1.113 markus 2824: if (nc == NULL) {
2825: error("auth_input_request_forwarding: channel_new failed");
1.123 markus 2826: auth_sock_cleanup_proc(pw);
1.124 markus 2827: fatal_remove_cleanup(auth_sock_cleanup_proc, pw);
1.113 markus 2828: close(sock);
2829: return 0;
2830: }
1.121 markus 2831: strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
1.59 markus 2832: return 1;
1.1 deraadt 2833: }
2834:
2835: /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2836:
1.49 markus 2837: void
1.154 markus 2838: auth_input_open_request(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2839: {
1.113 markus 2840: Channel *c = NULL;
2841: int remote_id, sock;
1.121 markus 2842: char *name;
1.41 markus 2843:
1.25 markus 2844: /* Read the remote channel number from the message. */
1.113 markus 2845: remote_id = packet_get_int();
1.152 markus 2846: packet_check_eom();
1.25 markus 2847:
1.27 markus 2848: /*
2849: * Get a connection to the local authentication agent (this may again
2850: * get forwarded).
2851: */
1.25 markus 2852: sock = ssh_get_authentication_socket();
2853:
1.27 markus 2854: /*
2855: * If we could not connect the agent, send an error message back to
2856: * the server. This should never happen unless the agent dies,
2857: * because authentication forwarding is only enabled if we have an
2858: * agent.
2859: */
1.113 markus 2860: if (sock >= 0) {
1.121 markus 2861: name = xstrdup("authentication agent connection");
2862: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2863: -1, 0, 0, 0, name, 1);
1.113 markus 2864: if (c == NULL) {
2865: error("auth_input_open_request: channel_new failed");
1.121 markus 2866: xfree(name);
1.113 markus 2867: close(sock);
2868: } else {
2869: c->remote_id = remote_id;
1.133 markus 2870: c->force_drain = 1;
1.113 markus 2871: }
2872: }
2873: if (c == NULL) {
1.25 markus 2874: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2875: packet_put_int(remote_id);
2876: } else {
2877: /* Send a confirmation to the remote host. */
2878: debug("Forwarding authentication connection.");
2879: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2880: packet_put_int(remote_id);
2881: packet_put_int(c->self);
1.25 markus 2882: }
2883: packet_send();
1.1 deraadt 2884: }
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