Annotation of src/usr.bin/ssh/channels.c, Revision 1.148
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.
1.128 markus 16: * Copyright (c) 1999, 2000, 2001 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"
1.148 ! deraadt 42: RCSID("$OpenBSD: channels.c,v 1.147 2001/12/08 17:49:28 stevesk 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;
1.131 markus 266: c->detach_user = NULL;
1.65 markus 267: c->input_filter = NULL;
1.25 markus 268: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 269: return c;
1.1 deraadt 270: }
1.52 markus 271:
1.132 markus 272: static int
273: channel_find_maxfd(void)
274: {
275: int i, max = 0;
276: Channel *c;
277:
278: for (i = 0; i < channels_alloc; i++) {
279: c = channels[i];
280: if (c != NULL) {
281: max = MAX(max, c->rfd);
282: max = MAX(max, c->wfd);
283: max = MAX(max, c->efd);
284: }
285: }
286: return max;
287: }
288:
289: int
290: channel_close_fd(int *fdp)
291: {
292: int ret = 0, fd = *fdp;
293:
294: if (fd != -1) {
295: ret = close(fd);
296: *fdp = -1;
297: if (fd == channel_max_fd)
298: channel_max_fd = channel_find_maxfd();
299: }
300: return ret;
301: }
302:
1.52 markus 303: /* Close all channel fd/socket. */
304:
1.127 itojun 305: static void
1.52 markus 306: channel_close_fds(Channel *c)
307: {
1.118 markus 308: debug3("channel_close_fds: channel %d: r %d w %d e %d",
309: c->self, c->rfd, c->wfd, c->efd);
310:
1.132 markus 311: channel_close_fd(&c->sock);
312: channel_close_fd(&c->rfd);
313: channel_close_fd(&c->wfd);
314: channel_close_fd(&c->efd);
1.121 markus 315: }
316:
317: /* Free the channel and close its fd/socket. */
318:
319: void
320: channel_free(Channel *c)
321: {
322: char *s;
323: int i, n;
324:
325: for (n = 0, i = 0; i < channels_alloc; i++)
326: if (channels[i])
327: n++;
328: debug("channel_free: channel %d: %s, nchannels %d", c->self,
329: c->remote_name ? c->remote_name : "???", n);
330:
331: s = channel_open_message();
332: debug3("channel_free: status: %s", s);
333: xfree(s);
334:
335: if (c->sock != -1)
336: shutdown(c->sock, SHUT_RDWR);
337: channel_close_fds(c);
338: buffer_free(&c->input);
339: buffer_free(&c->output);
340: buffer_free(&c->extended);
341: if (c->remote_name) {
342: xfree(c->remote_name);
343: c->remote_name = NULL;
344: }
345: channels[c->self] = NULL;
346: xfree(c);
347: }
348:
349: void
1.126 markus 350: channel_free_all(void)
1.121 markus 351: {
352: int i;
353:
1.126 markus 354: for (i = 0; i < channels_alloc; i++)
355: if (channels[i] != NULL)
356: channel_free(channels[i]);
1.131 markus 357: }
358:
1.121 markus 359: /*
360: * Closes the sockets/fds of all channels. This is used to close extra file
361: * descriptors after a fork.
362: */
363:
364: void
1.142 itojun 365: channel_close_all(void)
1.121 markus 366: {
367: int i;
368:
369: for (i = 0; i < channels_alloc; i++)
370: if (channels[i] != NULL)
371: channel_close_fds(channels[i]);
372: }
373:
374: /*
1.131 markus 375: * Stop listening to channels.
376: */
377:
378: void
379: channel_stop_listening(void)
380: {
381: int i;
382: Channel *c;
383:
384: for (i = 0; i < channels_alloc; i++) {
385: c = channels[i];
386: if (c != NULL) {
387: switch (c->type) {
388: case SSH_CHANNEL_AUTH_SOCKET:
389: case SSH_CHANNEL_PORT_LISTENER:
390: case SSH_CHANNEL_RPORT_LISTENER:
391: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 392: channel_close_fd(&c->sock);
1.131 markus 393: channel_free(c);
394: break;
395: }
396: }
397: }
398: }
399:
400: /*
1.121 markus 401: * Returns true if no channel has too much buffered data, and false if one or
402: * more channel is overfull.
403: */
404:
405: int
1.142 itojun 406: channel_not_very_much_buffered_data(void)
1.121 markus 407: {
408: u_int i;
409: Channel *c;
410:
411: for (i = 0; i < channels_alloc; i++) {
412: c = channels[i];
413: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 414: #if 0
415: if (!compat20 &&
416: buffer_len(&c->input) > packet_get_maxsize()) {
1.121 markus 417: debug("channel %d: big input buffer %d",
418: c->self, buffer_len(&c->input));
419: return 0;
420: }
1.136 markus 421: #endif
1.121 markus 422: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.136 markus 423: debug("channel %d: big output buffer %d > %d",
424: c->self, buffer_len(&c->output),
425: packet_get_maxsize());
1.121 markus 426: return 0;
427: }
428: }
429: }
430: return 1;
431: }
432:
433: /* Returns true if any channel is still open. */
434:
435: int
1.142 itojun 436: channel_still_open(void)
1.121 markus 437: {
438: int i;
439: Channel *c;
440:
441: for (i = 0; i < channels_alloc; i++) {
442: c = channels[i];
443: if (c == NULL)
444: continue;
445: switch (c->type) {
446: case SSH_CHANNEL_X11_LISTENER:
447: case SSH_CHANNEL_PORT_LISTENER:
448: case SSH_CHANNEL_RPORT_LISTENER:
449: case SSH_CHANNEL_CLOSED:
450: case SSH_CHANNEL_AUTH_SOCKET:
451: case SSH_CHANNEL_DYNAMIC:
452: case SSH_CHANNEL_CONNECTING:
453: case SSH_CHANNEL_ZOMBIE:
454: continue;
455: case SSH_CHANNEL_LARVAL:
456: if (!compat20)
457: fatal("cannot happen: SSH_CHANNEL_LARVAL");
458: continue;
459: case SSH_CHANNEL_OPENING:
460: case SSH_CHANNEL_OPEN:
461: case SSH_CHANNEL_X11_OPEN:
462: return 1;
463: case SSH_CHANNEL_INPUT_DRAINING:
464: case SSH_CHANNEL_OUTPUT_DRAINING:
465: if (!compat13)
466: fatal("cannot happen: OUT_DRAIN");
467: return 1;
468: default:
469: fatal("channel_still_open: bad channel type %d", c->type);
470: /* NOTREACHED */
471: }
472: }
473: return 0;
474: }
475:
476: /* Returns the id of an open channel suitable for keepaliving */
477:
478: int
1.142 itojun 479: channel_find_open(void)
1.121 markus 480: {
481: int i;
482: Channel *c;
483:
484: for (i = 0; i < channels_alloc; i++) {
485: c = channels[i];
486: if (c == NULL)
487: continue;
488: switch (c->type) {
489: case SSH_CHANNEL_CLOSED:
490: case SSH_CHANNEL_DYNAMIC:
491: case SSH_CHANNEL_X11_LISTENER:
492: case SSH_CHANNEL_PORT_LISTENER:
493: case SSH_CHANNEL_RPORT_LISTENER:
494: case SSH_CHANNEL_OPENING:
495: case SSH_CHANNEL_CONNECTING:
496: case SSH_CHANNEL_ZOMBIE:
497: continue;
498: case SSH_CHANNEL_LARVAL:
499: case SSH_CHANNEL_AUTH_SOCKET:
500: case SSH_CHANNEL_OPEN:
501: case SSH_CHANNEL_X11_OPEN:
502: return i;
503: case SSH_CHANNEL_INPUT_DRAINING:
504: case SSH_CHANNEL_OUTPUT_DRAINING:
505: if (!compat13)
506: fatal("cannot happen: OUT_DRAIN");
507: return i;
508: default:
509: fatal("channel_find_open: bad channel type %d", c->type);
510: /* NOTREACHED */
511: }
512: }
513: return -1;
514: }
515:
516:
517: /*
518: * Returns a message describing the currently open forwarded connections,
519: * suitable for sending to the client. The message contains crlf pairs for
520: * newlines.
521: */
522:
523: char *
1.142 itojun 524: channel_open_message(void)
1.121 markus 525: {
526: Buffer buffer;
527: Channel *c;
528: char buf[1024], *cp;
529: int i;
530:
531: buffer_init(&buffer);
532: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
533: buffer_append(&buffer, buf, strlen(buf));
534: for (i = 0; i < channels_alloc; i++) {
535: c = channels[i];
536: if (c == NULL)
537: continue;
538: switch (c->type) {
539: case SSH_CHANNEL_X11_LISTENER:
540: case SSH_CHANNEL_PORT_LISTENER:
541: case SSH_CHANNEL_RPORT_LISTENER:
542: case SSH_CHANNEL_CLOSED:
543: case SSH_CHANNEL_AUTH_SOCKET:
544: case SSH_CHANNEL_ZOMBIE:
545: continue;
546: case SSH_CHANNEL_LARVAL:
547: case SSH_CHANNEL_OPENING:
548: case SSH_CHANNEL_CONNECTING:
549: case SSH_CHANNEL_DYNAMIC:
550: case SSH_CHANNEL_OPEN:
551: case SSH_CHANNEL_X11_OPEN:
552: case SSH_CHANNEL_INPUT_DRAINING:
553: case SSH_CHANNEL_OUTPUT_DRAINING:
554: snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
555: c->self, c->remote_name,
556: c->type, c->remote_id,
557: c->istate, buffer_len(&c->input),
558: c->ostate, buffer_len(&c->output),
559: c->rfd, c->wfd);
560: buffer_append(&buffer, buf, strlen(buf));
561: continue;
562: default:
563: fatal("channel_open_message: bad channel type %d", c->type);
564: /* NOTREACHED */
565: }
566: }
567: buffer_append(&buffer, "\0", 1);
568: cp = xstrdup(buffer_ptr(&buffer));
569: buffer_free(&buffer);
570: return cp;
571: }
572:
573: void
574: channel_send_open(int id)
575: {
576: Channel *c = channel_lookup(id);
577: if (c == NULL) {
578: log("channel_send_open: %d: bad id", id);
579: return;
580: }
581: debug("send channel open %d", id);
582: packet_start(SSH2_MSG_CHANNEL_OPEN);
583: packet_put_cstring(c->ctype);
584: packet_put_int(c->self);
585: packet_put_int(c->local_window);
586: packet_put_int(c->local_maxpacket);
587: packet_send();
588: }
589:
590: void
591: channel_request(int id, char *service, int wantconfirm)
592: {
593: channel_request_start(id, service, wantconfirm);
594: packet_send();
595: debug("channel request %d: %s", id, service) ;
596: }
597: void
598: channel_request_start(int id, char *service, int wantconfirm)
599: {
600: Channel *c = channel_lookup(id);
601: if (c == NULL) {
602: log("channel_request: %d: bad id", id);
603: return;
604: }
605: packet_start(SSH2_MSG_CHANNEL_REQUEST);
606: packet_put_int(c->remote_id);
607: packet_put_cstring(service);
608: packet_put_char(wantconfirm);
609: }
610: void
611: channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
612: {
613: Channel *c = channel_lookup(id);
614: if (c == NULL) {
615: log("channel_register_callback: %d: bad id", id);
616: return;
617: }
618: c->cb_event = mtype;
619: c->cb_fn = fn;
620: c->cb_arg = arg;
621: }
622: void
623: channel_register_cleanup(int id, channel_callback_fn *fn)
624: {
625: Channel *c = channel_lookup(id);
626: if (c == NULL) {
627: log("channel_register_cleanup: %d: bad id", id);
628: return;
629: }
1.131 markus 630: c->detach_user = fn;
1.121 markus 631: }
632: void
633: channel_cancel_cleanup(int id)
634: {
635: Channel *c = channel_lookup(id);
636: if (c == NULL) {
637: log("channel_cancel_cleanup: %d: bad id", id);
638: return;
1.52 markus 639: }
1.131 markus 640: c->detach_user = NULL;
1.121 markus 641: }
642: void
643: channel_register_filter(int id, channel_filter_fn *fn)
644: {
645: Channel *c = channel_lookup(id);
646: if (c == NULL) {
647: log("channel_register_filter: %d: bad id", id);
648: return;
1.52 markus 649: }
1.121 markus 650: c->input_filter = fn;
1.52 markus 651: }
652:
1.49 markus 653: void
1.121 markus 654: channel_set_fds(int id, int rfd, int wfd, int efd,
655: int extusage, int nonblock)
1.1 deraadt 656: {
1.121 markus 657: Channel *c = channel_lookup(id);
658: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
659: fatal("channel_activate for non-larval channel %d.", id);
660: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
661: c->type = SSH_CHANNEL_OPEN;
662: /* XXX window size? */
663: c->local_window = c->local_window_max = c->local_maxpacket * 2;
664: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
665: packet_put_int(c->remote_id);
666: packet_put_int(c->local_window);
667: packet_send();
1.1 deraadt 668: }
669:
1.27 markus 670: /*
1.41 markus 671: * 'channel_pre*' are called just before select() to add any bits relevant to
672: * channels in the select bitmasks.
673: */
674: /*
675: * 'channel_post*': perform any appropriate operations for channels which
676: * have events pending.
1.27 markus 677: */
1.41 markus 678: typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
679: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
680: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
681:
1.127 itojun 682: static void
1.41 markus 683: channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
684: {
685: FD_SET(c->sock, readset);
686: }
687:
1.127 itojun 688: static void
1.75 markus 689: channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
690: {
691: debug3("channel %d: waiting for connection", c->self);
692: FD_SET(c->sock, writeset);
693: }
694:
1.127 itojun 695: static void
1.41 markus 696: channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
697: {
698: if (buffer_len(&c->input) < packet_get_maxsize())
699: FD_SET(c->sock, readset);
700: if (buffer_len(&c->output) > 0)
701: FD_SET(c->sock, writeset);
702: }
1.1 deraadt 703:
1.127 itojun 704: static void
1.41 markus 705: channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
706: {
707: /* test whether sockets are 'alive' for read/write */
708: if (c->istate == CHAN_INPUT_OPEN)
709: if (buffer_len(&c->input) < packet_get_maxsize())
710: FD_SET(c->sock, readset);
711: if (c->ostate == CHAN_OUTPUT_OPEN ||
712: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
713: if (buffer_len(&c->output) > 0) {
714: FD_SET(c->sock, writeset);
715: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
716: chan_obuf_empty(c);
717: }
718: }
719: }
720:
1.127 itojun 721: static void
1.44 markus 722: channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset)
723: {
724: if (c->istate == CHAN_INPUT_OPEN &&
725: c->remote_window > 0 &&
726: buffer_len(&c->input) < c->remote_window)
727: FD_SET(c->rfd, readset);
728: if (c->ostate == CHAN_OUTPUT_OPEN ||
729: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
730: if (buffer_len(&c->output) > 0) {
731: FD_SET(c->wfd, writeset);
732: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
733: chan_obuf_empty(c);
734: }
735: }
736: /** XXX check close conditions, too */
737: if (c->efd != -1) {
738: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
739: buffer_len(&c->extended) > 0)
740: FD_SET(c->efd, writeset);
741: else if (c->extended_usage == CHAN_EXTENDED_READ &&
742: buffer_len(&c->extended) < c->remote_window)
743: FD_SET(c->efd, readset);
744: }
745: }
746:
1.127 itojun 747: static void
1.41 markus 748: channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
749: {
750: if (buffer_len(&c->input) == 0) {
751: packet_start(SSH_MSG_CHANNEL_CLOSE);
752: packet_put_int(c->remote_id);
753: packet_send();
754: c->type = SSH_CHANNEL_CLOSED;
1.105 markus 755: debug("channel %d: closing after input drain.", c->self);
1.41 markus 756: }
757: }
758:
1.127 itojun 759: static void
1.41 markus 760: channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
761: {
762: if (buffer_len(&c->output) == 0)
1.113 markus 763: chan_mark_dead(c);
1.49 markus 764: else
1.41 markus 765: FD_SET(c->sock, writeset);
766: }
767:
768: /*
769: * This is a special state for X11 authentication spoofing. An opened X11
770: * connection (when authentication spoofing is being done) remains in this
771: * state until the first packet has been completely read. The authentication
772: * data in that packet is then substituted by the real data if it matches the
773: * fake data, and the channel is put into normal mode.
1.51 markus 774: * XXX All this happens at the client side.
1.121 markus 775: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 776: */
1.127 itojun 777: static int
1.121 markus 778: x11_open_helper(Buffer *b)
1.1 deraadt 779: {
1.77 markus 780: u_char *ucp;
781: u_int proto_len, data_len;
1.25 markus 782:
1.41 markus 783: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 784: if (buffer_len(b) < 12)
1.41 markus 785: return 0;
786:
787: /* Parse the lengths of variable-length fields. */
1.121 markus 788: ucp = (u_char *) buffer_ptr(b);
1.41 markus 789: if (ucp[0] == 0x42) { /* Byte order MSB first. */
790: proto_len = 256 * ucp[6] + ucp[7];
791: data_len = 256 * ucp[8] + ucp[9];
792: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
793: proto_len = ucp[6] + 256 * ucp[7];
794: data_len = ucp[8] + 256 * ucp[9];
795: } else {
796: debug("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 ! deraadt 797: ucp[0]);
1.41 markus 798: return -1;
799: }
800:
801: /* Check if the whole packet is in buffer. */
1.121 markus 802: if (buffer_len(b) <
1.41 markus 803: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
804: return 0;
805:
806: /* Check if authentication protocol matches. */
807: if (proto_len != strlen(x11_saved_proto) ||
808: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
809: debug("X11 connection uses different authentication protocol.");
810: return -1;
811: }
812: /* Check if authentication data matches our fake data. */
813: if (data_len != x11_fake_data_len ||
814: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
815: x11_fake_data, x11_fake_data_len) != 0) {
816: debug("X11 auth data does not match fake data.");
817: return -1;
818: }
819: /* Check fake data length */
820: if (x11_fake_data_len != x11_saved_data_len) {
821: error("X11 fake_data_len %d != saved_data_len %d",
822: x11_fake_data_len, x11_saved_data_len);
823: return -1;
824: }
825: /*
826: * Received authentication protocol and data match
827: * our fake data. Substitute the fake data with real
828: * data.
829: */
830: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
831: x11_saved_data, x11_saved_data_len);
832: return 1;
833: }
834:
1.127 itojun 835: static void
1.41 markus 836: channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
837: {
1.121 markus 838: int ret = x11_open_helper(&c->output);
1.41 markus 839: if (ret == 1) {
840: /* Start normal processing for the channel. */
841: c->type = SSH_CHANNEL_OPEN;
1.47 markus 842: channel_pre_open_13(c, readset, writeset);
1.41 markus 843: } else if (ret == -1) {
844: /*
845: * We have received an X11 connection that has bad
846: * authentication information.
847: */
1.98 millert 848: log("X11 connection rejected because of wrong authentication.");
1.41 markus 849: buffer_clear(&c->input);
850: buffer_clear(&c->output);
1.132 markus 851: channel_close_fd(&c->sock);
1.41 markus 852: c->sock = -1;
853: c->type = SSH_CHANNEL_CLOSED;
854: packet_start(SSH_MSG_CHANNEL_CLOSE);
855: packet_put_int(c->remote_id);
856: packet_send();
857: }
858: }
1.25 markus 859:
1.127 itojun 860: static void
1.51 markus 861: channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 862: {
1.121 markus 863: int ret = x11_open_helper(&c->output);
1.133 markus 864:
865: /* c->force_drain = 1; */
866:
1.41 markus 867: if (ret == 1) {
868: c->type = SSH_CHANNEL_OPEN;
1.57 markus 869: if (compat20)
870: channel_pre_open_20(c, readset, writeset);
871: else
872: channel_pre_open_15(c, readset, writeset);
1.41 markus 873: } else if (ret == -1) {
874: debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.51 markus 875: chan_read_failed(c); /** force close? */
1.41 markus 876: chan_write_failed(c);
877: debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
878: }
879: }
1.25 markus 880:
1.104 markus 881: /* try to decode a socks4 header */
1.127 itojun 882: static int
1.104 markus 883: channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
1.103 markus 884: {
885: u_char *p, *host;
1.109 markus 886: int len, have, i, found;
1.148 ! deraadt 887: char username[256];
1.103 markus 888: struct {
889: u_int8_t version;
890: u_int8_t command;
891: u_int16_t dest_port;
1.104 markus 892: struct in_addr dest_addr;
1.103 markus 893: } s4_req, s4_rsp;
894:
1.104 markus 895: debug2("channel %d: decode socks4", c->self);
1.109 markus 896:
897: have = buffer_len(&c->input);
898: len = sizeof(s4_req);
899: if (have < len)
900: return 0;
901: p = buffer_ptr(&c->input);
902: for (found = 0, i = len; i < have; i++) {
903: if (p[i] == '\0') {
904: found = 1;
905: break;
906: }
907: if (i > 1024) {
908: /* the peer is probably sending garbage */
909: debug("channel %d: decode socks4: too long",
910: c->self);
911: return -1;
912: }
913: }
914: if (!found)
915: return 0;
1.103 markus 916: buffer_get(&c->input, (char *)&s4_req.version, 1);
917: buffer_get(&c->input, (char *)&s4_req.command, 1);
918: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 919: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 920: have = buffer_len(&c->input);
1.103 markus 921: p = buffer_ptr(&c->input);
922: len = strlen(p);
1.106 markus 923: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 924: if (len > have)
1.104 markus 925: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 926: c->self, len, have);
927: strlcpy(username, p, sizeof(username));
928: buffer_consume(&c->input, len);
929: buffer_consume(&c->input, 1); /* trailing '\0' */
930:
1.104 markus 931: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 932: strlcpy(c->path, host, sizeof(c->path));
933: c->host_port = ntohs(s4_req.dest_port);
1.148 ! deraadt 934:
1.106 markus 935: debug("channel %d: dynamic request: socks4 host %s port %u command %u",
936: c->self, host, c->host_port, s4_req.command);
1.103 markus 937:
1.104 markus 938: if (s4_req.command != 1) {
939: debug("channel %d: cannot handle: socks4 cn %d",
940: c->self, s4_req.command);
941: return -1;
1.103 markus 942: }
1.104 markus 943: s4_rsp.version = 0; /* vn: 0 for reply */
944: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 945: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 946: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.103 markus 947: buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
1.104 markus 948: return 1;
949: }
950:
951: /* dynamic port forwarding */
1.127 itojun 952: static void
1.104 markus 953: channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
954: {
955: u_char *p;
956: int have, ret;
1.103 markus 957:
1.104 markus 958: have = buffer_len(&c->input);
1.137 markus 959: c->delayed = 0;
1.104 markus 960: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 961: /* buffer_dump(&c->input); */
1.104 markus 962: /* check if the fixed size part of the packet is in buffer. */
963: if (have < 4) {
964: /* need more */
965: FD_SET(c->sock, readset);
966: return;
967: }
968: /* try to guess the protocol */
969: p = buffer_ptr(&c->input);
970: switch (p[0]) {
971: case 0x04:
972: ret = channel_decode_socks4(c, readset, writeset);
973: break;
974: default:
975: ret = -1;
976: break;
977: }
978: if (ret < 0) {
1.113 markus 979: chan_mark_dead(c);
1.104 markus 980: } else if (ret == 0) {
981: debug2("channel %d: pre_dynamic: need more", c->self);
982: /* need more */
983: FD_SET(c->sock, readset);
984: } else {
985: /* switch to the next state */
986: c->type = SSH_CHANNEL_OPENING;
987: port_open_helper(c, "direct-tcpip");
988: }
1.103 markus 989: }
990:
1.41 markus 991: /* This is our fake X11 server socket. */
1.127 itojun 992: static void
1.41 markus 993: channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
994: {
1.113 markus 995: Channel *nc;
1.41 markus 996: struct sockaddr addr;
1.146 stevesk 997: int newsock, on = 1;
1.41 markus 998: socklen_t addrlen;
1.85 markus 999: char buf[16384], *remote_ipaddr;
1.51 markus 1000: int remote_port;
1.25 markus 1001:
1.41 markus 1002: if (FD_ISSET(c->sock, readset)) {
1003: debug("X11 connection requested.");
1004: addrlen = sizeof(addr);
1005: newsock = accept(c->sock, &addr, &addrlen);
1006: if (newsock < 0) {
1007: error("accept: %.100s", strerror(errno));
1008: return;
1009: }
1.146 stevesk 1010: if (setsockopt(newsock, IPPROTO_TCP, TCP_NODELAY, &on,
1011: sizeof on) == -1)
1012: error("setsockopt TCP_NODELAY: %.100s",
1013: strerror(errno));
1.85 markus 1014: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1015: remote_port = get_peer_port(newsock);
1.41 markus 1016: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1017: remote_ipaddr, remote_port);
1.51 markus 1018:
1.113 markus 1019: nc = channel_new("accepted x11 socket",
1.51 markus 1020: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1021: c->local_window_max, c->local_maxpacket,
1.71 markus 1022: 0, xstrdup(buf), 1);
1.113 markus 1023: if (nc == NULL) {
1024: close(newsock);
1025: xfree(remote_ipaddr);
1026: return;
1027: }
1.51 markus 1028: if (compat20) {
1029: packet_start(SSH2_MSG_CHANNEL_OPEN);
1030: packet_put_cstring("x11");
1.113 markus 1031: packet_put_int(nc->self);
1.51 markus 1032: packet_put_int(c->local_window_max);
1033: packet_put_int(c->local_maxpacket);
1.85 markus 1034: /* originator ipaddr and port */
1035: packet_put_cstring(remote_ipaddr);
1.57 markus 1036: if (datafellows & SSH_BUG_X11FWD) {
1037: debug("ssh2 x11 bug compat mode");
1038: } else {
1039: packet_put_int(remote_port);
1040: }
1.51 markus 1041: packet_send();
1042: } else {
1043: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1044: packet_put_int(nc->self);
1.121 markus 1045: if (packet_get_protocol_flags() &
1046: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1047: packet_put_cstring(buf);
1.51 markus 1048: packet_send();
1049: }
1.85 markus 1050: xfree(remote_ipaddr);
1.41 markus 1051: }
1052: }
1.25 markus 1053:
1.127 itojun 1054: static void
1.103 markus 1055: port_open_helper(Channel *c, char *rtype)
1056: {
1057: int direct;
1058: char buf[1024];
1059: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1060: u_short remote_port = get_peer_port(c->sock);
1061:
1062: direct = (strcmp(rtype, "direct-tcpip") == 0);
1063:
1064: snprintf(buf, sizeof buf,
1065: "%s: listening port %d for %.100s port %d, "
1066: "connect from %.200s port %d",
1067: rtype, c->listening_port, c->path, c->host_port,
1068: remote_ipaddr, remote_port);
1069:
1070: xfree(c->remote_name);
1071: c->remote_name = xstrdup(buf);
1072:
1073: if (compat20) {
1074: packet_start(SSH2_MSG_CHANNEL_OPEN);
1075: packet_put_cstring(rtype);
1076: packet_put_int(c->self);
1077: packet_put_int(c->local_window_max);
1078: packet_put_int(c->local_maxpacket);
1079: if (direct) {
1080: /* target host, port */
1081: packet_put_cstring(c->path);
1082: packet_put_int(c->host_port);
1083: } else {
1084: /* listen address, port */
1085: packet_put_cstring(c->path);
1086: packet_put_int(c->listening_port);
1087: }
1088: /* originator host and port */
1089: packet_put_cstring(remote_ipaddr);
1090: packet_put_int(remote_port);
1091: packet_send();
1092: } else {
1093: packet_start(SSH_MSG_PORT_OPEN);
1094: packet_put_int(c->self);
1095: packet_put_cstring(c->path);
1096: packet_put_int(c->host_port);
1.121 markus 1097: if (packet_get_protocol_flags() &
1098: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1099: packet_put_cstring(c->remote_name);
1100: packet_send();
1101: }
1102: xfree(remote_ipaddr);
1103: }
1104:
1.41 markus 1105: /*
1106: * This socket is listening for connections to a forwarded TCP/IP port.
1107: */
1.127 itojun 1108: static void
1.41 markus 1109: channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1110: {
1.103 markus 1111: Channel *nc;
1.41 markus 1112: struct sockaddr addr;
1.113 markus 1113: int newsock, nextstate;
1.41 markus 1114: socklen_t addrlen;
1.103 markus 1115: char *rtype;
1.73 markus 1116:
1.41 markus 1117: if (FD_ISSET(c->sock, readset)) {
1118: debug("Connection to port %d forwarding "
1119: "to %.100s port %d requested.",
1120: c->listening_port, c->path, c->host_port);
1.103 markus 1121:
1.137 markus 1122: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1123: nextstate = SSH_CHANNEL_OPENING;
1124: rtype = "forwarded-tcpip";
1125: } else {
1126: if (c->host_port == 0) {
1127: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1128: rtype = "dynamic-tcpip";
1.137 markus 1129: } else {
1130: nextstate = SSH_CHANNEL_OPENING;
1131: rtype = "direct-tcpip";
1132: }
1133: }
1.103 markus 1134:
1.41 markus 1135: addrlen = sizeof(addr);
1136: newsock = accept(c->sock, &addr, &addrlen);
1137: if (newsock < 0) {
1138: error("accept: %.100s", strerror(errno));
1139: return;
1140: }
1.113 markus 1141: nc = channel_new(rtype,
1.103 markus 1142: nextstate, newsock, newsock, -1,
1.41 markus 1143: c->local_window_max, c->local_maxpacket,
1.103 markus 1144: 0, xstrdup(rtype), 1);
1145: if (nc == NULL) {
1.113 markus 1146: error("channel_post_port_listener: no new channel:");
1147: close(newsock);
1.103 markus 1148: return;
1.41 markus 1149: }
1.103 markus 1150: nc->listening_port = c->listening_port;
1151: nc->host_port = c->host_port;
1152: strlcpy(nc->path, c->path, sizeof(nc->path));
1153:
1.137 markus 1154: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1155: /*
1156: * do not call the channel_post handler until
1157: * this flag has been reset by a pre-handler.
1158: * otherwise the FD_ISSET calls might overflow
1159: */
1160: nc->delayed = 1;
1161: } else {
1.103 markus 1162: port_open_helper(nc, rtype);
1.137 markus 1163: }
1.41 markus 1164: }
1165: }
1.25 markus 1166:
1.41 markus 1167: /*
1168: * This is the authentication agent socket listening for connections from
1169: * clients.
1170: */
1.127 itojun 1171: static void
1.41 markus 1172: channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1173: {
1.113 markus 1174: Channel *nc;
1.121 markus 1175: char *name;
1.113 markus 1176: int newsock;
1.41 markus 1177: struct sockaddr addr;
1178: socklen_t addrlen;
1.25 markus 1179:
1.41 markus 1180: if (FD_ISSET(c->sock, readset)) {
1181: addrlen = sizeof(addr);
1182: newsock = accept(c->sock, &addr, &addrlen);
1183: if (newsock < 0) {
1184: error("accept from auth socket: %.100s", strerror(errno));
1185: return;
1186: }
1.121 markus 1187: name = xstrdup("accepted auth socket");
1.113 markus 1188: nc = channel_new("accepted auth socket",
1.73 markus 1189: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1190: c->local_window_max, c->local_maxpacket,
1.121 markus 1191: 0, name, 1);
1.113 markus 1192: if (nc == NULL) {
1193: error("channel_post_auth_listener: channel_new failed");
1.121 markus 1194: xfree(name);
1.113 markus 1195: close(newsock);
1196: }
1.73 markus 1197: if (compat20) {
1198: packet_start(SSH2_MSG_CHANNEL_OPEN);
1199: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1200: packet_put_int(nc->self);
1.73 markus 1201: packet_put_int(c->local_window_max);
1202: packet_put_int(c->local_maxpacket);
1203: } else {
1204: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1205: packet_put_int(nc->self);
1.73 markus 1206: }
1.41 markus 1207: packet_send();
1208: }
1209: }
1.25 markus 1210:
1.127 itojun 1211: static void
1.75 markus 1212: channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1213: {
1.114 markus 1214: int err = 0;
1.129 stevesk 1215: socklen_t sz = sizeof(err);
1.114 markus 1216:
1.75 markus 1217: if (FD_ISSET(c->sock, writeset)) {
1.114 markus 1218: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
1219: &sz) < 0) {
1220: err = errno;
1221: error("getsockopt SO_ERROR failed");
1222: }
1223: if (err == 0) {
1224: debug("channel %d: connected", c->self);
1225: c->type = SSH_CHANNEL_OPEN;
1226: if (compat20) {
1227: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1228: packet_put_int(c->remote_id);
1229: packet_put_int(c->self);
1230: packet_put_int(c->local_window);
1231: packet_put_int(c->local_maxpacket);
1232: } else {
1233: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1234: packet_put_int(c->remote_id);
1235: packet_put_int(c->self);
1236: }
1.75 markus 1237: } else {
1.114 markus 1238: debug("channel %d: not connected: %s",
1239: c->self, strerror(err));
1240: if (compat20) {
1241: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1242: packet_put_int(c->remote_id);
1243: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1244: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1245: packet_put_cstring(strerror(err));
1246: packet_put_cstring("");
1247: }
1.75 markus 1248: } else {
1.114 markus 1249: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1250: packet_put_int(c->remote_id);
1.75 markus 1251: }
1.114 markus 1252: chan_mark_dead(c);
1.75 markus 1253: }
1.114 markus 1254: packet_send();
1.75 markus 1255: }
1256: }
1257:
1.127 itojun 1258: static int
1.41 markus 1259: channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1260: {
1261: char buf[16*1024];
1262: int len;
1.25 markus 1263:
1.118 markus 1264: if (c->rfd != -1 &&
1.41 markus 1265: FD_ISSET(c->rfd, readset)) {
1266: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1267: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1268: return 1;
1.41 markus 1269: if (len <= 0) {
1.51 markus 1270: debug("channel %d: read<=0 rfd %d len %d",
1.41 markus 1271: c->self, c->rfd, len);
1.104 markus 1272: if (c->type != SSH_CHANNEL_OPEN) {
1273: debug("channel %d: not open", c->self);
1.113 markus 1274: chan_mark_dead(c);
1.103 markus 1275: return -1;
1.104 markus 1276: } else if (compat13) {
1.41 markus 1277: buffer_consume(&c->output, buffer_len(&c->output));
1278: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.121 markus 1279: debug("channel %d: input draining.", c->self);
1.25 markus 1280: } else {
1.41 markus 1281: chan_read_failed(c);
1.25 markus 1282: }
1.41 markus 1283: return -1;
1284: }
1.143 deraadt 1285: if (c->input_filter != NULL) {
1.66 markus 1286: if (c->input_filter(c, buf, len) == -1) {
1.105 markus 1287: debug("channel %d: filter stops", c->self);
1.65 markus 1288: chan_read_failed(c);
1289: }
1290: } else {
1291: buffer_append(&c->input, buf, len);
1292: }
1.41 markus 1293: }
1294: return 1;
1295: }
1.127 itojun 1296: static int
1.41 markus 1297: channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1298: {
1.95 markus 1299: struct termios tio;
1.134 markus 1300: u_char *data;
1301: u_int dlen;
1.41 markus 1302: int len;
1.25 markus 1303:
1.41 markus 1304: /* Send buffered output data to the socket. */
1.118 markus 1305: if (c->wfd != -1 &&
1.41 markus 1306: FD_ISSET(c->wfd, writeset) &&
1307: buffer_len(&c->output) > 0) {
1.134 markus 1308: data = buffer_ptr(&c->output);
1309: dlen = buffer_len(&c->output);
1310: len = write(c->wfd, data, dlen);
1.53 markus 1311: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1312: return 1;
1.41 markus 1313: if (len <= 0) {
1.104 markus 1314: if (c->type != SSH_CHANNEL_OPEN) {
1315: debug("channel %d: not open", c->self);
1.113 markus 1316: chan_mark_dead(c);
1.104 markus 1317: return -1;
1318: } else if (compat13) {
1.41 markus 1319: buffer_consume(&c->output, buffer_len(&c->output));
1.121 markus 1320: debug("channel %d: input draining.", c->self);
1.41 markus 1321: c->type = SSH_CHANNEL_INPUT_DRAINING;
1322: } else {
1323: chan_write_failed(c);
1324: }
1325: return -1;
1.91 markus 1326: }
1.134 markus 1327: if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
1.91 markus 1328: if (tcgetattr(c->wfd, &tio) == 0 &&
1329: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1330: /*
1331: * Simulate echo to reduce the impact of
1.96 markus 1332: * traffic analysis. We need to match the
1.95 markus 1333: * size of a SSH2_MSG_CHANNEL_DATA message
1334: * (4 byte channel id + data)
1.91 markus 1335: */
1.95 markus 1336: packet_send_ignore(4 + len);
1.91 markus 1337: packet_send();
1338: }
1.25 markus 1339: }
1.41 markus 1340: buffer_consume(&c->output, len);
1.44 markus 1341: if (compat20 && len > 0) {
1342: c->local_consumed += len;
1343: }
1344: }
1345: return 1;
1346: }
1.127 itojun 1347: static int
1.44 markus 1348: channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1349: {
1350: char buf[16*1024];
1351: int len;
1352:
1.45 markus 1353: /** XXX handle drain efd, too */
1.44 markus 1354: if (c->efd != -1) {
1355: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1356: FD_ISSET(c->efd, writeset) &&
1357: buffer_len(&c->extended) > 0) {
1358: len = write(c->efd, buffer_ptr(&c->extended),
1359: buffer_len(&c->extended));
1.70 markus 1360: debug2("channel %d: written %d to efd %d",
1.44 markus 1361: c->self, len, c->efd);
1.93 markus 1362: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1363: return 1;
1364: if (len <= 0) {
1365: debug2("channel %d: closing write-efd %d",
1366: c->self, c->efd);
1.132 markus 1367: channel_close_fd(&c->efd);
1.93 markus 1368: } else {
1.44 markus 1369: buffer_consume(&c->extended, len);
1370: c->local_consumed += len;
1371: }
1372: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1373: FD_ISSET(c->efd, readset)) {
1374: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1375: debug2("channel %d: read %d from efd %d",
1.148 ! deraadt 1376: c->self, len, c->efd);
1.93 markus 1377: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1378: return 1;
1379: if (len <= 0) {
1380: debug2("channel %d: closing read-efd %d",
1.45 markus 1381: c->self, c->efd);
1.132 markus 1382: channel_close_fd(&c->efd);
1.93 markus 1383: } else {
1.44 markus 1384: buffer_append(&c->extended, buf, len);
1.93 markus 1385: }
1.44 markus 1386: }
1387: }
1388: return 1;
1389: }
1.127 itojun 1390: static int
1.93 markus 1391: channel_check_window(Channel *c)
1.44 markus 1392: {
1.104 markus 1393: if (c->type == SSH_CHANNEL_OPEN &&
1394: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.44 markus 1395: c->local_window < c->local_window_max/2 &&
1396: c->local_consumed > 0) {
1397: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1398: packet_put_int(c->remote_id);
1399: packet_put_int(c->local_consumed);
1400: packet_send();
1.70 markus 1401: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1402: c->self, c->local_window,
1403: c->local_consumed);
1404: c->local_window += c->local_consumed;
1405: c->local_consumed = 0;
1.1 deraadt 1406: }
1.41 markus 1407: return 1;
1.1 deraadt 1408: }
1409:
1.127 itojun 1410: static void
1.41 markus 1411: channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
1412: {
1.137 markus 1413: if (c->delayed)
1414: return;
1.41 markus 1415: channel_handle_rfd(c, readset, writeset);
1416: channel_handle_wfd(c, readset, writeset);
1417: }
1.1 deraadt 1418:
1.127 itojun 1419: static void
1.44 markus 1420: channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset)
1421: {
1.137 markus 1422: if (c->delayed)
1423: return;
1.44 markus 1424: channel_handle_rfd(c, readset, writeset);
1425: channel_handle_wfd(c, readset, writeset);
1426: channel_handle_efd(c, readset, writeset);
1.93 markus 1427:
1428: channel_check_window(c);
1.44 markus 1429: }
1430:
1.127 itojun 1431: static void
1.41 markus 1432: channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1.1 deraadt 1433: {
1.41 markus 1434: int len;
1435: /* Send buffered output data to the socket. */
1436: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1437: len = write(c->sock, buffer_ptr(&c->output),
1438: buffer_len(&c->output));
1439: if (len <= 0)
1440: buffer_consume(&c->output, buffer_len(&c->output));
1441: else
1442: buffer_consume(&c->output, len);
1443: }
1444: }
1.25 markus 1445:
1.127 itojun 1446: static void
1.44 markus 1447: channel_handler_init_20(void)
1448: {
1449: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
1.51 markus 1450: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1451: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1452: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1453: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1454: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1455: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1456: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1457:
1458: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
1459: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1460: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1461: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1462: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1463: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1464: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2;
1.44 markus 1465: }
1466:
1.127 itojun 1467: static void
1.41 markus 1468: channel_handler_init_13(void)
1469: {
1470: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1471: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1472: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1473: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1474: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1475: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1476: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1477: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1478: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1479:
1.41 markus 1480: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1481: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1482: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1483: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1484: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1485: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1486: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
1.41 markus 1487: }
1.25 markus 1488:
1.127 itojun 1489: static void
1.41 markus 1490: channel_handler_init_15(void)
1491: {
1492: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
1.51 markus 1493: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1494: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1495: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1496: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1497: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1498: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1499:
1.41 markus 1500: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1501: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1502: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1503: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1.75 markus 1504: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1505: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
1.41 markus 1506: }
1.27 markus 1507:
1.127 itojun 1508: static void
1.41 markus 1509: channel_handler_init(void)
1510: {
1511: int i;
1.148 ! deraadt 1512: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1513: channel_pre[i] = NULL;
1514: channel_post[i] = NULL;
1515: }
1.44 markus 1516: if (compat20)
1517: channel_handler_init_20();
1518: else if (compat13)
1.41 markus 1519: channel_handler_init_13();
1520: else
1521: channel_handler_init_15();
1522: }
1.25 markus 1523:
1.140 markus 1524: /* gc dead channels */
1525: static void
1526: channel_garbage_collect(Channel *c)
1527: {
1528: if (c == NULL)
1529: return;
1530: if (c->detach_user != NULL) {
1531: if (!chan_is_dead(c, 0))
1532: return;
1533: debug("channel %d: gc: notify user", c->self);
1534: c->detach_user(c->self, NULL);
1535: /* if we still have a callback */
1536: if (c->detach_user != NULL)
1537: return;
1538: debug("channel %d: gc: user detached", c->self);
1539: }
1540: if (!chan_is_dead(c, 1))
1541: return;
1542: debug("channel %d: garbage collecting", c->self);
1543: channel_free(c);
1544: }
1545:
1.127 itojun 1546: static void
1.41 markus 1547: channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1548: {
1549: static int did_init = 0;
1550: int i;
1551: Channel *c;
1.25 markus 1552:
1.41 markus 1553: if (!did_init) {
1554: channel_handler_init();
1555: did_init = 1;
1556: }
1557: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1558: c = channels[i];
1559: if (c == NULL)
1.41 markus 1560: continue;
1.118 markus 1561: if (ftab[c->type] != NULL)
1562: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1563: channel_garbage_collect(c);
1.1 deraadt 1564: }
1565: }
1566:
1.121 markus 1567: /*
1568: * Allocate/update select bitmasks and add any bits relevant to channels in
1569: * select bitmasks.
1570: */
1.49 markus 1571: void
1.100 markus 1572: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.132 markus 1573: int *nallocp, int rekeying)
1.41 markus 1574: {
1.84 markus 1575: int n;
1576: u_int sz;
1577:
1578: n = MAX(*maxfdp, channel_max_fd);
1579:
1580: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.132 markus 1581: /* perhaps check sz < nalloc/2 and shrink? */
1582: if (*readsetp == NULL || sz > *nallocp) {
1583: *readsetp = xrealloc(*readsetp, sz);
1584: *writesetp = xrealloc(*writesetp, sz);
1585: *nallocp = sz;
1.84 markus 1586: }
1.132 markus 1587: *maxfdp = n;
1.84 markus 1588: memset(*readsetp, 0, sz);
1589: memset(*writesetp, 0, sz);
1590:
1.100 markus 1591: if (!rekeying)
1592: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1593: }
1594:
1.121 markus 1595: /*
1596: * After select, perform any appropriate operations for channels which have
1597: * events pending.
1598: */
1.49 markus 1599: void
1.41 markus 1600: channel_after_select(fd_set * readset, fd_set * writeset)
1601: {
1602: channel_handler(channel_post, readset, writeset);
1603: }
1604:
1.121 markus 1605:
1.84 markus 1606: /* If there is data to send to the connection, enqueue some of it now. */
1.1 deraadt 1607:
1.49 markus 1608: void
1.142 itojun 1609: channel_output_poll(void)
1.1 deraadt 1610: {
1.25 markus 1611: int len, i;
1.41 markus 1612: Channel *c;
1.1 deraadt 1613:
1.25 markus 1614: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1615: c = channels[i];
1616: if (c == NULL)
1617: continue;
1.37 markus 1618:
1.121 markus 1619: /*
1620: * We are only interested in channels that can have buffered
1621: * incoming data.
1622: */
1.37 markus 1623: if (compat13) {
1.41 markus 1624: if (c->type != SSH_CHANNEL_OPEN &&
1625: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1626: continue;
1627: } else {
1.41 markus 1628: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1629: continue;
1630: }
1.46 markus 1631: if (compat20 &&
1632: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1633: /* XXX is this true? */
1.140 markus 1634: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1635: continue;
1636: }
1.25 markus 1637:
1638: /* Get the amount of buffered data for this channel. */
1.93 markus 1639: if ((c->istate == CHAN_INPUT_OPEN ||
1640: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1641: (len = buffer_len(&c->input)) > 0) {
1.121 markus 1642: /*
1643: * Send some data for the other side over the secure
1644: * connection.
1645: */
1.44 markus 1646: if (compat20) {
1647: if (len > c->remote_window)
1648: len = c->remote_window;
1649: if (len > c->remote_maxpacket)
1650: len = c->remote_maxpacket;
1.25 markus 1651: } else {
1.44 markus 1652: if (packet_is_interactive()) {
1653: if (len > 1024)
1654: len = 512;
1655: } else {
1656: /* Keep the packets at reasonable size. */
1657: if (len > packet_get_maxsize()/2)
1658: len = packet_get_maxsize()/2;
1659: }
1.25 markus 1660: }
1.41 markus 1661: if (len > 0) {
1.44 markus 1662: packet_start(compat20 ?
1663: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1664: packet_put_int(c->remote_id);
1665: packet_put_string(buffer_ptr(&c->input), len);
1666: packet_send();
1667: buffer_consume(&c->input, len);
1668: c->remote_window -= len;
1669: }
1670: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1671: if (compat13)
1672: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1673: /*
1674: * input-buffer is empty and read-socket shutdown:
1675: * tell peer, that we will not send more data: send IEOF
1676: */
1.41 markus 1677: chan_ibuf_empty(c);
1.25 markus 1678: }
1.44 markus 1679: /* Send extended data, i.e. stderr */
1680: if (compat20 &&
1681: c->remote_window > 0 &&
1682: (len = buffer_len(&c->extended)) > 0 &&
1683: c->extended_usage == CHAN_EXTENDED_READ) {
1.93 markus 1684: debug2("channel %d: rwin %d elen %d euse %d",
1685: c->self, c->remote_window, buffer_len(&c->extended),
1686: c->extended_usage);
1.44 markus 1687: if (len > c->remote_window)
1688: len = c->remote_window;
1689: if (len > c->remote_maxpacket)
1690: len = c->remote_maxpacket;
1691: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1692: packet_put_int(c->remote_id);
1693: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1694: packet_put_string(buffer_ptr(&c->extended), len);
1695: packet_send();
1696: buffer_consume(&c->extended, len);
1697: c->remote_window -= len;
1.93 markus 1698: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1699: }
1.25 markus 1700: }
1.1 deraadt 1701: }
1702:
1.121 markus 1703:
1704: /* -- protocol input */
1.1 deraadt 1705:
1.49 markus 1706: void
1.69 markus 1707: channel_input_data(int type, int plen, void *ctxt)
1.1 deraadt 1708: {
1.37 markus 1709: int id;
1.25 markus 1710: char *data;
1.77 markus 1711: u_int data_len;
1.41 markus 1712: Channel *c;
1.25 markus 1713:
1714: /* Get the channel number and verify it. */
1.37 markus 1715: id = packet_get_int();
1.41 markus 1716: c = channel_lookup(id);
1717: if (c == NULL)
1.37 markus 1718: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 1719:
1720: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 1721: if (c->type != SSH_CHANNEL_OPEN &&
1722: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 1723: return;
1724:
1725: /* same for protocol 1.5 if output end is no longer open */
1.41 markus 1726: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
1.25 markus 1727: return;
1728:
1729: /* Get the data. */
1730: data = packet_get_string(&data_len);
1.48 markus 1731: packet_done();
1.41 markus 1732:
1.143 deraadt 1733: if (compat20) {
1.44 markus 1734: if (data_len > c->local_maxpacket) {
1735: log("channel %d: rcvd big packet %d, maxpack %d",
1736: c->self, data_len, c->local_maxpacket);
1737: }
1738: if (data_len > c->local_window) {
1739: log("channel %d: rcvd too much data %d, win %d",
1740: c->self, data_len, c->local_window);
1741: xfree(data);
1742: return;
1743: }
1744: c->local_window -= data_len;
1745: }else{
1746: packet_integrity_check(plen, 4 + 4 + data_len, type);
1747: }
1.41 markus 1748: buffer_append(&c->output, data, data_len);
1.25 markus 1749: xfree(data);
1.1 deraadt 1750: }
1.121 markus 1751:
1.49 markus 1752: void
1.69 markus 1753: channel_input_extended_data(int type, int plen, void *ctxt)
1.44 markus 1754: {
1755: int id;
1756: int tcode;
1757: char *data;
1.77 markus 1758: u_int data_len;
1.44 markus 1759: Channel *c;
1760:
1761: /* Get the channel number and verify it. */
1762: id = packet_get_int();
1763: c = channel_lookup(id);
1764:
1765: if (c == NULL)
1766: packet_disconnect("Received extended_data for bad channel %d.", id);
1767: if (c->type != SSH_CHANNEL_OPEN) {
1768: log("channel %d: ext data for non open", id);
1769: return;
1770: }
1771: tcode = packet_get_int();
1772: if (c->efd == -1 ||
1773: c->extended_usage != CHAN_EXTENDED_WRITE ||
1774: tcode != SSH2_EXTENDED_DATA_STDERR) {
1775: log("channel %d: bad ext data", c->self);
1776: return;
1777: }
1778: data = packet_get_string(&data_len);
1.48 markus 1779: packet_done();
1.44 markus 1780: if (data_len > c->local_window) {
1781: log("channel %d: rcvd too much extended_data %d, win %d",
1782: c->self, data_len, c->local_window);
1783: xfree(data);
1784: return;
1785: }
1.70 markus 1786: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 1787: c->local_window -= data_len;
1788: buffer_append(&c->extended, data, data_len);
1789: xfree(data);
1790: }
1791:
1.49 markus 1792: void
1.69 markus 1793: channel_input_ieof(int type, int plen, void *ctxt)
1.41 markus 1794: {
1795: int id;
1796: Channel *c;
1797:
1798: packet_integrity_check(plen, 4, type);
1799:
1800: id = packet_get_int();
1801: c = channel_lookup(id);
1802: if (c == NULL)
1803: packet_disconnect("Received ieof for nonexistent channel %d.", id);
1804: chan_rcvd_ieof(c);
1.133 markus 1805:
1806: /* XXX force input close */
1807: if (c->force_drain) {
1808: debug("channel %d: FORCE input drain", c->self);
1809: c->istate = CHAN_INPUT_WAIT_DRAIN;
1810: }
1811:
1.41 markus 1812: }
1.1 deraadt 1813:
1.49 markus 1814: void
1.69 markus 1815: channel_input_close(int type, int plen, void *ctxt)
1.1 deraadt 1816: {
1.41 markus 1817: int id;
1818: Channel *c;
1.1 deraadt 1819:
1.41 markus 1820: packet_integrity_check(plen, 4, type);
1821:
1822: id = packet_get_int();
1823: c = channel_lookup(id);
1824: if (c == NULL)
1825: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 1826:
1827: /*
1828: * Send a confirmation that we have closed the channel and no more
1829: * data is coming for it.
1830: */
1.25 markus 1831: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 1832: packet_put_int(c->remote_id);
1.25 markus 1833: packet_send();
1834:
1.27 markus 1835: /*
1836: * If the channel is in closed state, we have sent a close request,
1837: * and the other side will eventually respond with a confirmation.
1838: * Thus, we cannot free the channel here, because then there would be
1839: * no-one to receive the confirmation. The channel gets freed when
1840: * the confirmation arrives.
1841: */
1.41 markus 1842: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 1843: /*
1844: * Not a closed channel - mark it as draining, which will
1845: * cause it to be freed later.
1846: */
1.41 markus 1847: buffer_consume(&c->input, buffer_len(&c->input));
1848: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 1849: }
1.1 deraadt 1850: }
1851:
1.41 markus 1852: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.49 markus 1853: void
1.69 markus 1854: channel_input_oclose(int type, int plen, void *ctxt)
1.41 markus 1855: {
1856: int id = packet_get_int();
1857: Channel *c = channel_lookup(id);
1858: packet_integrity_check(plen, 4, type);
1859: if (c == NULL)
1860: packet_disconnect("Received oclose for nonexistent channel %d.", id);
1861: chan_rcvd_oclose(c);
1862: }
1.1 deraadt 1863:
1.49 markus 1864: void
1.69 markus 1865: channel_input_close_confirmation(int type, int plen, void *ctxt)
1.1 deraadt 1866: {
1.41 markus 1867: int id = packet_get_int();
1868: Channel *c = channel_lookup(id);
1.1 deraadt 1869:
1.48 markus 1870: packet_done();
1.41 markus 1871: if (c == NULL)
1872: packet_disconnect("Received close confirmation for "
1873: "out-of-range channel %d.", id);
1874: if (c->type != SSH_CHANNEL_CLOSED)
1875: packet_disconnect("Received close confirmation for "
1876: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 1877: channel_free(c);
1.1 deraadt 1878: }
1879:
1.49 markus 1880: void
1.69 markus 1881: channel_input_open_confirmation(int type, int plen, void *ctxt)
1.1 deraadt 1882: {
1.41 markus 1883: int id, remote_id;
1884: Channel *c;
1.1 deraadt 1885:
1.44 markus 1886: if (!compat20)
1887: packet_integrity_check(plen, 4 + 4, type);
1.25 markus 1888:
1.41 markus 1889: id = packet_get_int();
1890: c = channel_lookup(id);
1.25 markus 1891:
1.41 markus 1892: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1893: packet_disconnect("Received open confirmation for "
1894: "non-opening channel %d.", id);
1895: remote_id = packet_get_int();
1.27 markus 1896: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 1897: c->remote_id = remote_id;
1898: c->type = SSH_CHANNEL_OPEN;
1.44 markus 1899:
1900: if (compat20) {
1901: c->remote_window = packet_get_int();
1902: c->remote_maxpacket = packet_get_int();
1.48 markus 1903: packet_done();
1.44 markus 1904: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1905: debug2("callback start");
1.44 markus 1906: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1907: debug2("callback done");
1.44 markus 1908: }
1909: debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1910: c->remote_window, c->remote_maxpacket);
1911: }
1.1 deraadt 1912: }
1913:
1.127 itojun 1914: static char *
1.114 markus 1915: reason2txt(int reason)
1916: {
1.143 deraadt 1917: switch (reason) {
1.114 markus 1918: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1919: return "administratively prohibited";
1920: case SSH2_OPEN_CONNECT_FAILED:
1921: return "connect failed";
1922: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1923: return "unknown channel type";
1924: case SSH2_OPEN_RESOURCE_SHORTAGE:
1925: return "resource shortage";
1926: }
1.117 stevesk 1927: return "unknown reason";
1.114 markus 1928: }
1929:
1.49 markus 1930: void
1.69 markus 1931: channel_input_open_failure(int type, int plen, void *ctxt)
1.1 deraadt 1932: {
1.86 markus 1933: int id, reason;
1934: char *msg = NULL, *lang = NULL;
1.41 markus 1935: Channel *c;
1936:
1.44 markus 1937: if (!compat20)
1938: packet_integrity_check(plen, 4, type);
1.41 markus 1939:
1940: id = packet_get_int();
1941: c = channel_lookup(id);
1.25 markus 1942:
1.41 markus 1943: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1944: packet_disconnect("Received open failure for "
1945: "non-opening channel %d.", id);
1.44 markus 1946: if (compat20) {
1.86 markus 1947: reason = packet_get_int();
1.110 markus 1948: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 1949: msg = packet_get_string(NULL);
1950: lang = packet_get_string(NULL);
1951: }
1.48 markus 1952: packet_done();
1.114 markus 1953: log("channel %d: open failed: %s%s%s", id,
1954: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 1955: if (msg != NULL)
1956: xfree(msg);
1957: if (lang != NULL)
1958: xfree(lang);
1.44 markus 1959: }
1.25 markus 1960: /* Free the channel. This will also close the socket. */
1.113 markus 1961: channel_free(c);
1.1 deraadt 1962: }
1963:
1.44 markus 1964: void
1.69 markus 1965: channel_input_channel_request(int type, int plen, void *ctxt)
1.44 markus 1966: {
1967: int id;
1968: Channel *c;
1969:
1970: id = packet_get_int();
1971: c = channel_lookup(id);
1972:
1973: if (c == NULL ||
1974: (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1975: packet_disconnect("Received request for "
1976: "non-open channel %d.", id);
1977: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1978: debug2("callback start");
1.44 markus 1979: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1980: debug2("callback done");
1.44 markus 1981: } else {
1982: char *service = packet_get_string(NULL);
1.94 markus 1983: debug("channel %d: rcvd request for %s", c->self, service);
1.70 markus 1984: debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
1.44 markus 1985: xfree(service);
1986: }
1987: }
1988:
1.121 markus 1989: void
1990: channel_input_window_adjust(int type, int plen, void *ctxt)
1991: {
1992: Channel *c;
1993: int id, adjust;
1994:
1995: if (!compat20)
1996: return;
1997:
1998: /* Get the channel number and verify it. */
1999: id = packet_get_int();
2000: c = channel_lookup(id);
1.1 deraadt 2001:
1.121 markus 2002: if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
2003: log("Received window adjust for "
2004: "non-open channel %d.", id);
2005: return;
2006: }
2007: adjust = packet_get_int();
2008: packet_done();
2009: debug2("channel %d: rcvd adjust %d", id, adjust);
2010: c->remote_window += adjust;
2011: }
1.1 deraadt 2012:
1.121 markus 2013: void
2014: channel_input_port_open(int type, int plen, void *ctxt)
1.1 deraadt 2015: {
1.121 markus 2016: Channel *c = NULL;
2017: u_short host_port;
2018: char *host, *originator_string;
2019: int remote_id, sock = -1;
2020:
2021: remote_id = packet_get_int();
2022: host = packet_get_string(NULL);
2023: host_port = packet_get_int();
1.25 markus 2024:
1.121 markus 2025: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2026: originator_string = packet_get_string(NULL);
2027: } else {
2028: originator_string = xstrdup("unknown (remote did not supply name)");
2029: }
2030: packet_done();
2031: sock = channel_connect_to(host, host_port);
2032: if (sock != -1) {
2033: c = channel_new("connected socket",
2034: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2035: originator_string, 1);
2036: if (c == NULL) {
2037: error("channel_input_port_open: channel_new failed");
2038: close(sock);
2039: } else {
2040: c->remote_id = remote_id;
1.25 markus 2041: }
2042: }
1.121 markus 2043: if (c == NULL) {
2044: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2045: packet_put_int(remote_id);
2046: packet_send();
2047: }
2048: xfree(host);
1.1 deraadt 2049: }
2050:
1.121 markus 2051:
2052: /* -- tcp forwarding */
1.135 markus 2053:
2054: void
2055: channel_set_af(int af)
2056: {
2057: IPv4or6 = af;
2058: }
1.121 markus 2059:
1.27 markus 2060: /*
2061: * Initiate forwarding of connections to local port "port" through the secure
2062: * channel to host:port from remote side.
2063: */
1.87 markus 2064: int
1.73 markus 2065: channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
2066: u_short port_to_connect, int gateway_ports)
2067: {
1.87 markus 2068: return channel_request_forwarding(
1.73 markus 2069: NULL, listen_port,
2070: host_to_connect, port_to_connect,
2071: gateway_ports, /*remote_fwd*/ 0);
2072: }
1.1 deraadt 2073:
1.73 markus 2074: /*
2075: * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
2076: * (SSH_CHANNEL_RPORT_LISTENER).
2077: */
1.87 markus 2078: int
1.73 markus 2079: channel_request_forwarding(
2080: const char *listen_address, u_short listen_port,
2081: const char *host_to_connect, u_short port_to_connect,
2082: int gateway_ports, int remote_fwd)
1.25 markus 2083: {
1.113 markus 2084: Channel *c;
1.121 markus 2085: int success, sock, on = 1, type;
1.35 markus 2086: struct addrinfo hints, *ai, *aitop;
2087: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.73 markus 2088: const char *host;
1.28 markus 2089: struct linger linger;
1.25 markus 2090:
1.87 markus 2091: success = 0;
2092:
1.73 markus 2093: if (remote_fwd) {
2094: host = listen_address;
1.121 markus 2095: type = SSH_CHANNEL_RPORT_LISTENER;
1.73 markus 2096: } else {
2097: host = host_to_connect;
1.121 markus 2098: type = SSH_CHANNEL_PORT_LISTENER;
1.73 markus 2099: }
2100:
1.113 markus 2101: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2102: error("Forward host name too long.");
2103: return success;
2104: }
1.25 markus 2105:
1.73 markus 2106: /* XXX listen_address is currently ignored */
1.28 markus 2107: /*
1.35 markus 2108: * getaddrinfo returns a loopback address if the hostname is
2109: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2110: */
1.35 markus 2111: memset(&hints, 0, sizeof(hints));
2112: hints.ai_family = IPv4or6;
2113: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2114: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2115: snprintf(strport, sizeof strport, "%d", listen_port);
1.35 markus 2116: if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2117: packet_disconnect("getaddrinfo: fatal error");
2118:
2119: for (ai = aitop; ai; ai = ai->ai_next) {
2120: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2121: continue;
2122: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2123: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.73 markus 2124: error("channel_request_forwarding: getnameinfo failed");
1.35 markus 2125: continue;
2126: }
2127: /* Create a port to listen for the host. */
2128: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2129: if (sock < 0) {
2130: /* this is no error since kernel may not support ipv6 */
2131: verbose("socket: %.100s", strerror(errno));
2132: continue;
2133: }
2134: /*
2135: * Set socket options. We would like the socket to disappear
2136: * as soon as it has been closed for whatever reason.
2137: */
2138: setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
2139: linger.l_onoff = 1;
2140: linger.l_linger = 5;
2141: setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
2142: debug("Local forwarding listening on %s port %s.", ntop, strport);
2143:
2144: /* Bind the socket to the address. */
2145: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2146: /* address can be in use ipv6 address is already bound */
2147: verbose("bind: %.100s", strerror(errno));
2148: close(sock);
2149: continue;
2150: }
2151: /* Start listening for connections on the socket. */
2152: if (listen(sock, 5) < 0) {
2153: error("listen: %.100s", strerror(errno));
2154: close(sock);
2155: continue;
2156: }
2157: /* Allocate a channel number for the socket. */
1.121 markus 2158: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2159: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.71 markus 2160: 0, xstrdup("port listener"), 1);
1.113 markus 2161: if (c == NULL) {
2162: error("channel_request_forwarding: channel_new failed");
2163: close(sock);
2164: continue;
2165: }
2166: strlcpy(c->path, host, sizeof(c->path));
2167: c->host_port = port_to_connect;
2168: c->listening_port = listen_port;
1.35 markus 2169: success = 1;
2170: }
2171: if (success == 0)
1.87 markus 2172: error("channel_request_forwarding: cannot listen to port: %d",
2173: listen_port);
1.35 markus 2174: freeaddrinfo(aitop);
1.87 markus 2175: return success;
1.25 markus 2176: }
1.1 deraadt 2177:
1.27 markus 2178: /*
2179: * Initiate forwarding of connections to port "port" on remote host through
2180: * the secure channel to host:port from local side.
2181: */
1.1 deraadt 2182:
1.49 markus 2183: void
1.73 markus 2184: channel_request_remote_forwarding(u_short listen_port,
2185: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2186: {
1.73 markus 2187: int payload_len, type, success = 0;
2188:
1.25 markus 2189: /* Record locally that connection to this host/port is permitted. */
2190: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2191: fatal("channel_request_remote_forwarding: too many forwards");
2192:
2193: /* Send the forward request to the remote side. */
1.44 markus 2194: if (compat20) {
2195: const char *address_to_bind = "0.0.0.0";
2196: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2197: packet_put_cstring("tcpip-forward");
2198: packet_put_char(0); /* boolean: want reply */
2199: packet_put_cstring(address_to_bind);
2200: packet_put_int(listen_port);
1.73 markus 2201: packet_send();
2202: packet_write_wait();
2203: /* Assume that server accepts the request */
2204: success = 1;
1.44 markus 2205: } else {
2206: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2207: packet_put_int(listen_port);
2208: packet_put_cstring(host_to_connect);
1.44 markus 2209: packet_put_int(port_to_connect);
2210: packet_send();
2211: packet_write_wait();
1.73 markus 2212:
2213: /* Wait for response from the remote side. */
2214: type = packet_read(&payload_len);
2215: switch (type) {
2216: case SSH_SMSG_SUCCESS:
2217: success = 1;
2218: break;
2219: case SSH_SMSG_FAILURE:
2220: log("Warning: Server denied remote port forwarding.");
2221: break;
2222: default:
2223: /* Unknown packet */
2224: packet_disconnect("Protocol error for port forward request:"
2225: "received packet type %d.", type);
2226: }
2227: }
2228: if (success) {
2229: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2230: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2231: permitted_opens[num_permitted_opens].listen_port = listen_port;
2232: num_permitted_opens++;
1.44 markus 2233: }
1.1 deraadt 2234: }
2235:
1.27 markus 2236: /*
2237: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2238: * listening for the port, and sends back a success reply (or disconnect
2239: * message if there was an error). This never returns if there was an error.
2240: */
1.1 deraadt 2241:
1.49 markus 2242: void
1.56 markus 2243: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2244: {
1.31 markus 2245: u_short port, host_port;
1.25 markus 2246: char *hostname;
1.1 deraadt 2247:
1.25 markus 2248: /* Get arguments from the packet. */
2249: port = packet_get_int();
2250: hostname = packet_get_string(NULL);
2251: host_port = packet_get_int();
2252:
1.27 markus 2253: /*
2254: * Check that an unprivileged user is not trying to forward a
2255: * privileged port.
2256: */
1.25 markus 2257: if (port < IPPORT_RESERVED && !is_root)
2258: packet_disconnect("Requested forwarding of port %d but user is not root.",
2259: port);
1.73 markus 2260: /* Initiate forwarding */
1.56 markus 2261: channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
1.25 markus 2262:
2263: /* Free the argument string. */
2264: xfree(hostname);
1.1 deraadt 2265: }
2266:
1.99 markus 2267: /*
2268: * Permits opening to any host/port if permitted_opens[] is empty. This is
2269: * usually called by the server, because the user could connect to any port
2270: * anyway, and the server has no way to know but to trust the client anyway.
2271: */
2272: void
1.142 itojun 2273: channel_permit_all_opens(void)
1.99 markus 2274: {
2275: if (num_permitted_opens == 0)
2276: all_opens_permitted = 1;
2277: }
2278:
1.101 markus 2279: void
1.99 markus 2280: channel_add_permitted_opens(char *host, int port)
2281: {
2282: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2283: fatal("channel_request_remote_forwarding: too many forwards");
2284: debug("allow port forwarding to host %s port %d", host, port);
2285:
2286: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2287: permitted_opens[num_permitted_opens].port_to_connect = port;
2288: num_permitted_opens++;
2289:
2290: all_opens_permitted = 0;
2291: }
2292:
1.101 markus 2293: void
1.99 markus 2294: channel_clear_permitted_opens(void)
2295: {
2296: int i;
2297:
2298: for (i = 0; i < num_permitted_opens; i++)
2299: xfree(permitted_opens[i].host_to_connect);
2300: num_permitted_opens = 0;
2301:
2302: }
2303:
2304:
2305: /* return socket to remote host, port */
1.127 itojun 2306: static int
1.99 markus 2307: connect_to(const char *host, u_short port)
1.41 markus 2308: {
2309: struct addrinfo hints, *ai, *aitop;
2310: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2311: int gaierr;
2312: int sock = -1;
2313:
2314: memset(&hints, 0, sizeof(hints));
2315: hints.ai_family = IPv4or6;
2316: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2317: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2318: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2319: error("connect_to %.100s: unknown host (%s)", host,
2320: gai_strerror(gaierr));
1.41 markus 2321: return -1;
2322: }
2323: for (ai = aitop; ai; ai = ai->ai_next) {
2324: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2325: continue;
2326: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2327: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2328: error("connect_to: getnameinfo failed");
1.41 markus 2329: continue;
2330: }
2331: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2332: if (sock < 0) {
2333: error("socket: %.100s", strerror(errno));
2334: continue;
2335: }
1.80 markus 2336: if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
1.75 markus 2337: fatal("connect_to: F_SETFL: %s", strerror(errno));
2338: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2339: errno != EINPROGRESS) {
1.99 markus 2340: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2341: strerror(errno));
2342: close(sock);
1.89 stevesk 2343: continue; /* fail -- try next */
1.41 markus 2344: }
2345: break; /* success */
2346:
2347: }
2348: freeaddrinfo(aitop);
2349: if (!ai) {
1.99 markus 2350: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2351: return -1;
2352: }
2353: /* success */
2354: return sock;
2355: }
1.99 markus 2356:
1.73 markus 2357: int
1.130 stevesk 2358: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2359: {
2360: int i;
1.99 markus 2361:
1.73 markus 2362: for (i = 0; i < num_permitted_opens; i++)
2363: if (permitted_opens[i].listen_port == listen_port)
1.99 markus 2364: return connect_to(
1.73 markus 2365: permitted_opens[i].host_to_connect,
2366: permitted_opens[i].port_to_connect);
1.74 markus 2367: error("WARNING: Server requests forwarding for unknown listen_port %d",
2368: listen_port);
1.73 markus 2369: return -1;
2370: }
2371:
1.99 markus 2372: /* Check if connecting to that port is permitted and connect. */
2373: int
2374: channel_connect_to(const char *host, u_short port)
2375: {
2376: int i, permit;
2377:
2378: permit = all_opens_permitted;
2379: if (!permit) {
2380: for (i = 0; i < num_permitted_opens; i++)
2381: if (permitted_opens[i].port_to_connect == port &&
2382: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2383: permit = 1;
2384:
2385: }
2386: if (!permit) {
2387: log("Received request to connect to host %.100s port %d, "
2388: "but the request was denied.", host, port);
2389: return -1;
2390: }
2391: return connect_to(host, port);
2392: }
2393:
1.121 markus 2394: /* -- X11 forwarding */
1.1 deraadt 2395:
1.27 markus 2396: /*
2397: * Creates an internet domain socket for listening for X11 connections.
1.141 stevesk 2398: * Returns a suitable display number for the DISPLAY variable, or -1 if
2399: * an error occurs.
1.27 markus 2400: */
1.141 stevesk 2401: int
2402: x11_create_display_inet(int x11_display_offset, int gateway_ports)
1.1 deraadt 2403: {
1.31 markus 2404: int display_number, sock;
2405: u_short port;
1.35 markus 2406: struct addrinfo hints, *ai, *aitop;
2407: char strport[NI_MAXSERV];
2408: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 2409:
1.33 markus 2410: for (display_number = x11_display_offset;
1.148 ! deraadt 2411: display_number < MAX_DISPLAYS;
! 2412: display_number++) {
1.25 markus 2413: port = 6000 + display_number;
1.35 markus 2414: memset(&hints, 0, sizeof(hints));
2415: hints.ai_family = IPv4or6;
1.141 stevesk 2416: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
1.35 markus 2417: hints.ai_socktype = SOCK_STREAM;
2418: snprintf(strport, sizeof strport, "%d", port);
2419: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2420: error("getaddrinfo: %.100s", gai_strerror(gaierr));
1.141 stevesk 2421: return -1;
1.25 markus 2422: }
1.35 markus 2423: for (ai = aitop; ai; ai = ai->ai_next) {
2424: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2425: continue;
2426: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2427: if (sock < 0) {
2428: error("socket: %.100s", strerror(errno));
1.141 stevesk 2429: return -1;
1.35 markus 2430: }
2431: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2432: debug("bind port %d: %.100s", port, strerror(errno));
2433: close(sock);
2434: for (n = 0; n < num_socks; n++) {
2435: close(socks[n]);
2436: }
2437: num_socks = 0;
2438: break;
2439: }
2440: socks[num_socks++] = sock;
2441: if (num_socks == NUM_SOCKS)
2442: break;
1.25 markus 2443: }
1.83 stevesk 2444: freeaddrinfo(aitop);
1.35 markus 2445: if (num_socks > 0)
2446: break;
1.25 markus 2447: }
2448: if (display_number >= MAX_DISPLAYS) {
2449: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 2450: return -1;
1.25 markus 2451: }
2452: /* Start listening for connections on the socket. */
1.35 markus 2453: for (n = 0; n < num_socks; n++) {
2454: sock = socks[n];
2455: if (listen(sock, 5) < 0) {
2456: error("listen: %.100s", strerror(errno));
2457: close(sock);
1.141 stevesk 2458: return -1;
1.35 markus 2459: }
1.25 markus 2460: }
1.35 markus 2461:
2462: /* Allocate a channel for each socket. */
2463: for (n = 0; n < num_socks; n++) {
2464: sock = socks[n];
1.51 markus 2465: (void) channel_new("x11 listener",
2466: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2467: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.71 markus 2468: 0, xstrdup("X11 inet listener"), 1);
1.35 markus 2469: }
1.1 deraadt 2470:
1.141 stevesk 2471: /* Return the display number for the DISPLAY environment variable. */
2472: return display_number;
1.1 deraadt 2473: }
2474:
1.127 itojun 2475: static int
1.77 markus 2476: connect_local_xsocket(u_int dnr)
1.1 deraadt 2477: {
1.25 markus 2478: int sock;
2479: struct sockaddr_un addr;
2480:
1.147 stevesk 2481: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2482: if (sock < 0)
2483: error("socket: %.100s", strerror(errno));
2484: memset(&addr, 0, sizeof(addr));
2485: addr.sun_family = AF_UNIX;
2486: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
2487: if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2488: return sock;
2489: close(sock);
1.25 markus 2490: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2491: return -1;
1.1 deraadt 2492: }
2493:
1.51 markus 2494: int
2495: x11_connect_display(void)
1.1 deraadt 2496: {
1.146 stevesk 2497: int display_number, sock = 0, on = 1;
1.25 markus 2498: const char *display;
1.51 markus 2499: char buf[1024], *cp;
1.35 markus 2500: struct addrinfo hints, *ai, *aitop;
2501: char strport[NI_MAXSERV];
2502: int gaierr;
1.25 markus 2503:
2504: /* Try to open a socket for the local X server. */
2505: display = getenv("DISPLAY");
2506: if (!display) {
2507: error("DISPLAY not set.");
1.51 markus 2508: return -1;
1.25 markus 2509: }
1.27 markus 2510: /*
2511: * Now we decode the value of the DISPLAY variable and make a
2512: * connection to the real X server.
2513: */
2514:
2515: /*
2516: * Check if it is a unix domain socket. Unix domain displays are in
2517: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2518: */
1.25 markus 2519: if (strncmp(display, "unix:", 5) == 0 ||
2520: display[0] == ':') {
2521: /* Connect to the unix domain socket. */
2522: if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2523: error("Could not parse display number from DISPLAY: %.100s",
1.148 ! deraadt 2524: display);
1.51 markus 2525: return -1;
1.25 markus 2526: }
2527: /* Create a socket. */
2528: sock = connect_local_xsocket(display_number);
2529: if (sock < 0)
1.51 markus 2530: return -1;
1.25 markus 2531:
2532: /* OK, we now have a connection to the display. */
1.51 markus 2533: return sock;
1.25 markus 2534: }
1.27 markus 2535: /*
2536: * Connect to an inet socket. The DISPLAY value is supposedly
2537: * hostname:d[.s], where hostname may also be numeric IP address.
2538: */
1.145 stevesk 2539: strlcpy(buf, display, sizeof(buf));
1.25 markus 2540: cp = strchr(buf, ':');
2541: if (!cp) {
2542: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 2543: return -1;
1.25 markus 2544: }
2545: *cp = 0;
1.27 markus 2546: /* buf now contains the host name. But first we parse the display number. */
1.25 markus 2547: if (sscanf(cp + 1, "%d", &display_number) != 1) {
2548: error("Could not parse display number from DISPLAY: %.100s",
1.148 ! deraadt 2549: display);
1.51 markus 2550: return -1;
1.25 markus 2551: }
1.35 markus 2552:
2553: /* Look up the host address */
2554: memset(&hints, 0, sizeof(hints));
2555: hints.ai_family = IPv4or6;
2556: hints.ai_socktype = SOCK_STREAM;
2557: snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2558: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2559: error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
1.51 markus 2560: return -1;
1.25 markus 2561: }
1.35 markus 2562: for (ai = aitop; ai; ai = ai->ai_next) {
2563: /* Create a socket. */
2564: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2565: if (sock < 0) {
2566: debug("socket: %.100s", strerror(errno));
1.41 markus 2567: continue;
2568: }
2569: /* Connect it to the display. */
2570: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2571: debug("connect %.100s port %d: %.100s", buf,
2572: 6000 + display_number, strerror(errno));
2573: close(sock);
2574: continue;
2575: }
2576: /* Success */
2577: break;
1.35 markus 2578: }
2579: freeaddrinfo(aitop);
2580: if (!ai) {
1.49 markus 2581: error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
1.35 markus 2582: strerror(errno));
1.51 markus 2583: return -1;
1.25 markus 2584: }
1.146 stevesk 2585: if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on) == -1)
2586: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
1.51 markus 2587: return sock;
2588: }
2589:
2590: /*
2591: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2592: * the remote channel number. We should do whatever we want, and respond
2593: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2594: */
2595:
2596: void
1.69 markus 2597: x11_input_open(int type, int plen, void *ctxt)
1.51 markus 2598: {
1.113 markus 2599: Channel *c = NULL;
2600: int remote_id, sock = 0;
1.51 markus 2601: char *remote_host;
1.25 markus 2602:
1.113 markus 2603: debug("Received X11 open request.");
1.51 markus 2604:
1.113 markus 2605: remote_id = packet_get_int();
1.121 markus 2606:
2607: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 2608: remote_host = packet_get_string(NULL);
1.51 markus 2609: } else {
2610: remote_host = xstrdup("unknown (remote did not supply name)");
2611: }
1.113 markus 2612: packet_done();
1.25 markus 2613:
1.51 markus 2614: /* Obtain a connection to the real X display. */
2615: sock = x11_connect_display();
1.113 markus 2616: if (sock != -1) {
2617: /* Allocate a channel for this connection. */
2618: c = channel_new("connected x11 socket",
2619: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2620: remote_host, 1);
2621: if (c == NULL) {
2622: error("x11_input_open: channel_new failed");
2623: close(sock);
2624: } else {
2625: c->remote_id = remote_id;
1.133 markus 2626: c->force_drain = 1;
1.113 markus 2627: }
2628: }
2629: if (c == NULL) {
1.51 markus 2630: /* Send refusal to the remote host. */
2631: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2632: packet_put_int(remote_id);
1.51 markus 2633: } else {
2634: /* Send a confirmation to the remote host. */
2635: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 2636: packet_put_int(remote_id);
2637: packet_put_int(c->self);
1.51 markus 2638: }
1.113 markus 2639: packet_send();
1.72 markus 2640: }
2641:
2642: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2643: void
2644: deny_input_open(int type, int plen, void *ctxt)
2645: {
2646: int rchan = packet_get_int();
1.143 deraadt 2647: switch (type) {
1.72 markus 2648: case SSH_SMSG_AGENT_OPEN:
2649: error("Warning: ssh server tried agent forwarding.");
2650: break;
2651: case SSH_SMSG_X11_OPEN:
2652: error("Warning: ssh server tried X11 forwarding.");
2653: break;
2654: default:
2655: error("deny_input_open: type %d plen %d", type, plen);
2656: break;
2657: }
2658: error("Warning: this is probably a break in attempt by a malicious server.");
2659: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2660: packet_put_int(rchan);
2661: packet_send();
1.1 deraadt 2662: }
2663:
1.27 markus 2664: /*
2665: * Requests forwarding of X11 connections, generates fake authentication
2666: * data, and enables authentication spoofing.
1.121 markus 2667: * This should be called in the client only.
1.27 markus 2668: */
1.49 markus 2669: void
1.51 markus 2670: x11_request_forwarding_with_spoofing(int client_session_id,
2671: const char *proto, const char *data)
1.1 deraadt 2672: {
1.77 markus 2673: u_int data_len = (u_int) strlen(data) / 2;
1.90 markus 2674: u_int i, value, len;
1.25 markus 2675: char *new_data;
2676: int screen_number;
2677: const char *cp;
2678: u_int32_t rand = 0;
2679:
2680: cp = getenv("DISPLAY");
2681: if (cp)
2682: cp = strchr(cp, ':');
2683: if (cp)
2684: cp = strchr(cp, '.');
2685: if (cp)
2686: screen_number = atoi(cp + 1);
2687: else
2688: screen_number = 0;
2689:
2690: /* Save protocol name. */
2691: x11_saved_proto = xstrdup(proto);
2692:
1.27 markus 2693: /*
2694: * Extract real authentication data and generate fake data of the
2695: * same length.
2696: */
1.25 markus 2697: x11_saved_data = xmalloc(data_len);
2698: x11_fake_data = xmalloc(data_len);
2699: for (i = 0; i < data_len; i++) {
2700: if (sscanf(data + 2 * i, "%2x", &value) != 1)
2701: fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2702: if (i % 4 == 0)
2703: rand = arc4random();
2704: x11_saved_data[i] = value;
2705: x11_fake_data[i] = rand & 0xff;
2706: rand >>= 8;
2707: }
2708: x11_saved_data_len = data_len;
2709: x11_fake_data_len = data_len;
2710:
2711: /* Convert the fake data into hex. */
1.90 markus 2712: len = 2 * data_len + 1;
2713: new_data = xmalloc(len);
1.25 markus 2714: for (i = 0; i < data_len; i++)
1.90 markus 2715: snprintf(new_data + 2 * i, len - 2 * i,
2716: "%02x", (u_char) x11_fake_data[i]);
1.25 markus 2717:
2718: /* Send the request packet. */
1.51 markus 2719: if (compat20) {
2720: channel_request_start(client_session_id, "x11-req", 0);
2721: packet_put_char(0); /* XXX bool single connection */
2722: } else {
2723: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2724: }
2725: packet_put_cstring(proto);
2726: packet_put_cstring(new_data);
1.25 markus 2727: packet_put_int(screen_number);
2728: packet_send();
2729: packet_write_wait();
2730: xfree(new_data);
1.1 deraadt 2731: }
2732:
1.121 markus 2733:
2734: /* -- agent forwarding */
2735:
1.1 deraadt 2736: /* Sends a message to the server to request authentication fd forwarding. */
2737:
1.49 markus 2738: void
1.142 itojun 2739: auth_request_forwarding(void)
1.1 deraadt 2740: {
1.25 markus 2741: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2742: packet_send();
2743: packet_write_wait();
1.1 deraadt 2744: }
2745:
1.27 markus 2746: /*
2747: * Returns the name of the forwarded authentication socket. Returns NULL if
2748: * there is no forwarded authentication socket. The returned value points to
2749: * a static buffer.
2750: */
1.1 deraadt 2751:
1.25 markus 2752: char *
1.142 itojun 2753: auth_get_socket_name(void)
1.1 deraadt 2754: {
1.121 markus 2755: return auth_sock_name;
1.1 deraadt 2756: }
2757:
1.12 markus 2758: /* removes the agent forwarding socket */
2759:
1.49 markus 2760: void
1.123 markus 2761: auth_sock_cleanup_proc(void *_pw)
1.25 markus 2762: {
1.123 markus 2763: struct passwd *pw = _pw;
2764:
1.122 markus 2765: if (auth_sock_name) {
1.123 markus 2766: temporarily_use_uid(pw);
1.122 markus 2767: unlink(auth_sock_name);
2768: rmdir(auth_sock_dir);
2769: auth_sock_name = NULL;
1.123 markus 2770: restore_uid();
1.122 markus 2771: }
1.12 markus 2772: }
2773:
1.27 markus 2774: /*
1.59 markus 2775: * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
1.27 markus 2776: * This starts forwarding authentication requests.
2777: */
1.1 deraadt 2778:
1.59 markus 2779: int
1.25 markus 2780: auth_input_request_forwarding(struct passwd * pw)
1.1 deraadt 2781: {
1.113 markus 2782: Channel *nc;
2783: int sock;
1.25 markus 2784: struct sockaddr_un sunaddr;
2785:
1.121 markus 2786: if (auth_get_socket_name() != NULL) {
2787: error("authentication forwarding requested twice.");
2788: return 0;
2789: }
1.25 markus 2790:
2791: /* Temporarily drop privileged uid for mkdir/bind. */
1.102 markus 2792: temporarily_use_uid(pw);
1.25 markus 2793:
2794: /* Allocate a buffer for the socket name, and format the name. */
1.121 markus 2795: auth_sock_name = xmalloc(MAXPATHLEN);
2796: auth_sock_dir = xmalloc(MAXPATHLEN);
2797: strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1.25 markus 2798:
2799: /* Create private directory for socket */
1.121 markus 2800: if (mkdtemp(auth_sock_dir) == NULL) {
2801: packet_send_debug("Agent forwarding disabled: "
2802: "mkdtemp() failed: %.100s", strerror(errno));
1.59 markus 2803: restore_uid();
1.121 markus 2804: xfree(auth_sock_name);
2805: xfree(auth_sock_dir);
2806: auth_sock_name = NULL;
2807: auth_sock_dir = NULL;
1.59 markus 2808: return 0;
2809: }
1.121 markus 2810: snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d",
2811: auth_sock_dir, (int) getpid());
1.25 markus 2812:
1.122 markus 2813: /* delete agent socket on fatal() */
1.123 markus 2814: fatal_add_cleanup(auth_sock_cleanup_proc, pw);
1.122 markus 2815:
1.25 markus 2816: /* Create the socket. */
2817: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2818: if (sock < 0)
2819: packet_disconnect("socket: %.100s", strerror(errno));
2820:
2821: /* Bind it to the name. */
2822: memset(&sunaddr, 0, sizeof(sunaddr));
2823: sunaddr.sun_family = AF_UNIX;
1.145 stevesk 2824: strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
1.25 markus 2825:
2826: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2827: packet_disconnect("bind: %.100s", strerror(errno));
2828:
2829: /* Restore the privileged uid. */
2830: restore_uid();
2831:
2832: /* Start listening on the socket. */
2833: if (listen(sock, 5) < 0)
2834: packet_disconnect("listen: %.100s", strerror(errno));
2835:
2836: /* Allocate a channel for the authentication agent socket. */
1.113 markus 2837: nc = channel_new("auth socket",
1.73 markus 2838: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2839: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2840: 0, xstrdup("auth socket"), 1);
1.113 markus 2841: if (nc == NULL) {
2842: error("auth_input_request_forwarding: channel_new failed");
1.123 markus 2843: auth_sock_cleanup_proc(pw);
1.124 markus 2844: fatal_remove_cleanup(auth_sock_cleanup_proc, pw);
1.113 markus 2845: close(sock);
2846: return 0;
2847: }
1.121 markus 2848: strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
1.59 markus 2849: return 1;
1.1 deraadt 2850: }
2851:
2852: /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2853:
1.49 markus 2854: void
1.69 markus 2855: auth_input_open_request(int type, int plen, void *ctxt)
1.1 deraadt 2856: {
1.113 markus 2857: Channel *c = NULL;
2858: int remote_id, sock;
1.121 markus 2859: char *name;
1.41 markus 2860:
2861: packet_integrity_check(plen, 4, type);
1.25 markus 2862:
2863: /* Read the remote channel number from the message. */
1.113 markus 2864: remote_id = packet_get_int();
1.25 markus 2865:
1.27 markus 2866: /*
2867: * Get a connection to the local authentication agent (this may again
2868: * get forwarded).
2869: */
1.25 markus 2870: sock = ssh_get_authentication_socket();
2871:
1.27 markus 2872: /*
2873: * If we could not connect the agent, send an error message back to
2874: * the server. This should never happen unless the agent dies,
2875: * because authentication forwarding is only enabled if we have an
2876: * agent.
2877: */
1.113 markus 2878: if (sock >= 0) {
1.121 markus 2879: name = xstrdup("authentication agent connection");
2880: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2881: -1, 0, 0, 0, name, 1);
1.113 markus 2882: if (c == NULL) {
2883: error("auth_input_open_request: channel_new failed");
1.121 markus 2884: xfree(name);
1.113 markus 2885: close(sock);
2886: } else {
2887: c->remote_id = remote_id;
1.133 markus 2888: c->force_drain = 1;
1.113 markus 2889: }
2890: }
2891: if (c == NULL) {
1.25 markus 2892: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2893: packet_put_int(remote_id);
2894: } else {
2895: /* Send a confirmation to the remote host. */
2896: debug("Forwarding authentication connection.");
2897: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2898: packet_put_int(remote_id);
2899: packet_put_int(c->self);
1.25 markus 2900: }
2901: packet_send();
1.1 deraadt 2902: }