Annotation of src/usr.bin/ssh/channels.c, Revision 1.163
1.1 deraadt 1: /*
1.26 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
5: * This file contains functions for generic socket connection forwarding.
6: * There is also code for initiating connection forwarding for X11 connections,
7: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 8: *
1.67 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
14: *
1.44 markus 15: * SSH2 support added by Markus Friedl.
1.156 markus 16: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 17: * Copyright (c) 1999 Dug Song. All rights reserved.
18: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
19: *
20: * Redistribution and use in source and binary forms, with or without
21: * modification, are permitted provided that the following conditions
22: * are met:
23: * 1. Redistributions of source code must retain the above copyright
24: * notice, this list of conditions and the following disclaimer.
25: * 2. Redistributions in binary form must reproduce the above copyright
26: * notice, this list of conditions and the following disclaimer in the
27: * documentation and/or other materials provided with the distribution.
28: *
29: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
30: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
31: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
32: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
33: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
34: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
38: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 39: */
1.1 deraadt 40:
41: #include "includes.h"
1.163 ! stevesk 42: RCSID("$OpenBSD: channels.c,v 1.162 2002/01/24 21:09:25 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) {
220: channels_alloc = 10;
1.113 markus 221: channels = xmalloc(channels_alloc * sizeof(Channel *));
1.25 markus 222: for (i = 0; i < channels_alloc; i++)
1.113 markus 223: channels[i] = NULL;
1.126 markus 224: fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL);
1.25 markus 225: }
226: /* Try to find a free slot where to put the new channel. */
227: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 228: if (channels[i] == NULL) {
1.25 markus 229: /* Found a free slot. */
230: found = i;
231: break;
232: }
233: if (found == -1) {
1.27 markus 234: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 235: found = channels_alloc;
236: channels_alloc += 10;
1.70 markus 237: debug2("channel: expanding %d", channels_alloc);
1.113 markus 238: channels = xrealloc(channels, channels_alloc * sizeof(Channel *));
1.25 markus 239: for (i = found; i < channels_alloc; i++)
1.113 markus 240: channels[i] = NULL;
1.25 markus 241: }
1.113 markus 242: /* Initialize and return new channel. */
243: c = channels[found] = xmalloc(sizeof(Channel));
1.137 markus 244: memset(c, 0, sizeof(Channel));
1.25 markus 245: buffer_init(&c->input);
246: buffer_init(&c->output);
1.41 markus 247: buffer_init(&c->extended);
1.159 markus 248: c->ostate = CHAN_OUTPUT_OPEN;
249: c->istate = CHAN_INPUT_OPEN;
250: c->flags = 0;
1.71 markus 251: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
1.25 markus 252: c->self = found;
253: c->type = type;
1.41 markus 254: c->ctype = ctype;
1.51 markus 255: c->local_window = window;
256: c->local_window_max = window;
257: c->local_consumed = 0;
258: c->local_maxpacket = maxpack;
1.25 markus 259: c->remote_id = -1;
260: c->remote_name = remote_name;
1.41 markus 261: c->remote_window = 0;
262: c->remote_maxpacket = 0;
263: c->cb_fn = NULL;
264: c->cb_arg = NULL;
265: c->cb_event = 0;
1.133 markus 266: c->force_drain = 0;
1.149 markus 267: c->single_connection = 0;
1.131 markus 268: c->detach_user = NULL;
1.65 markus 269: c->input_filter = NULL;
1.25 markus 270: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 271: return c;
1.1 deraadt 272: }
1.52 markus 273:
1.132 markus 274: static int
275: channel_find_maxfd(void)
276: {
277: int i, max = 0;
278: Channel *c;
279:
280: for (i = 0; i < channels_alloc; i++) {
281: c = channels[i];
282: if (c != NULL) {
283: max = MAX(max, c->rfd);
284: max = MAX(max, c->wfd);
285: max = MAX(max, c->efd);
286: }
287: }
288: return max;
289: }
290:
291: int
292: channel_close_fd(int *fdp)
293: {
294: int ret = 0, fd = *fdp;
295:
296: if (fd != -1) {
297: ret = close(fd);
298: *fdp = -1;
299: if (fd == channel_max_fd)
300: channel_max_fd = channel_find_maxfd();
301: }
302: return ret;
303: }
304:
1.52 markus 305: /* Close all channel fd/socket. */
306:
1.127 itojun 307: static void
1.52 markus 308: channel_close_fds(Channel *c)
309: {
1.118 markus 310: debug3("channel_close_fds: channel %d: r %d w %d e %d",
311: c->self, c->rfd, c->wfd, c->efd);
312:
1.132 markus 313: channel_close_fd(&c->sock);
314: channel_close_fd(&c->rfd);
315: channel_close_fd(&c->wfd);
316: channel_close_fd(&c->efd);
1.121 markus 317: }
318:
319: /* Free the channel and close its fd/socket. */
320:
321: void
322: channel_free(Channel *c)
323: {
324: char *s;
325: int i, n;
326:
327: for (n = 0, i = 0; i < channels_alloc; i++)
328: if (channels[i])
329: n++;
330: debug("channel_free: channel %d: %s, nchannels %d", c->self,
331: c->remote_name ? c->remote_name : "???", n);
332:
333: s = channel_open_message();
334: debug3("channel_free: status: %s", s);
335: xfree(s);
336:
337: if (c->sock != -1)
338: shutdown(c->sock, SHUT_RDWR);
339: channel_close_fds(c);
340: buffer_free(&c->input);
341: buffer_free(&c->output);
342: buffer_free(&c->extended);
343: if (c->remote_name) {
344: xfree(c->remote_name);
345: c->remote_name = NULL;
346: }
347: channels[c->self] = NULL;
348: xfree(c);
349: }
350:
351: void
1.126 markus 352: channel_free_all(void)
1.121 markus 353: {
354: int i;
355:
1.126 markus 356: for (i = 0; i < channels_alloc; i++)
357: if (channels[i] != NULL)
358: channel_free(channels[i]);
1.131 markus 359: }
360:
1.121 markus 361: /*
362: * Closes the sockets/fds of all channels. This is used to close extra file
363: * descriptors after a fork.
364: */
365:
366: void
1.142 itojun 367: channel_close_all(void)
1.121 markus 368: {
369: int i;
370:
371: for (i = 0; i < channels_alloc; i++)
372: if (channels[i] != NULL)
373: channel_close_fds(channels[i]);
374: }
375:
376: /*
1.131 markus 377: * Stop listening to channels.
378: */
379:
380: void
381: channel_stop_listening(void)
382: {
383: int i;
384: Channel *c;
385:
386: for (i = 0; i < channels_alloc; i++) {
387: c = channels[i];
388: if (c != NULL) {
389: switch (c->type) {
390: case SSH_CHANNEL_AUTH_SOCKET:
391: case SSH_CHANNEL_PORT_LISTENER:
392: case SSH_CHANNEL_RPORT_LISTENER:
393: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 394: channel_close_fd(&c->sock);
1.131 markus 395: channel_free(c);
396: break;
397: }
398: }
399: }
400: }
401:
402: /*
1.121 markus 403: * Returns true if no channel has too much buffered data, and false if one or
404: * more channel is overfull.
405: */
406:
407: int
1.142 itojun 408: channel_not_very_much_buffered_data(void)
1.121 markus 409: {
410: u_int i;
411: Channel *c;
412:
413: for (i = 0; i < channels_alloc; i++) {
414: c = channels[i];
415: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 416: #if 0
417: if (!compat20 &&
418: buffer_len(&c->input) > packet_get_maxsize()) {
1.121 markus 419: debug("channel %d: big input buffer %d",
420: c->self, buffer_len(&c->input));
421: return 0;
422: }
1.136 markus 423: #endif
1.121 markus 424: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.136 markus 425: debug("channel %d: big output buffer %d > %d",
426: c->self, buffer_len(&c->output),
427: packet_get_maxsize());
1.121 markus 428: return 0;
429: }
430: }
431: }
432: return 1;
433: }
434:
435: /* Returns true if any channel is still open. */
436:
437: int
1.142 itojun 438: channel_still_open(void)
1.121 markus 439: {
440: int i;
441: Channel *c;
442:
443: for (i = 0; i < channels_alloc; i++) {
444: c = channels[i];
445: if (c == NULL)
446: continue;
447: switch (c->type) {
448: case SSH_CHANNEL_X11_LISTENER:
449: case SSH_CHANNEL_PORT_LISTENER:
450: case SSH_CHANNEL_RPORT_LISTENER:
451: case SSH_CHANNEL_CLOSED:
452: case SSH_CHANNEL_AUTH_SOCKET:
453: case SSH_CHANNEL_DYNAMIC:
454: case SSH_CHANNEL_CONNECTING:
455: case SSH_CHANNEL_ZOMBIE:
456: continue;
457: case SSH_CHANNEL_LARVAL:
458: if (!compat20)
459: fatal("cannot happen: SSH_CHANNEL_LARVAL");
460: continue;
461: case SSH_CHANNEL_OPENING:
462: case SSH_CHANNEL_OPEN:
463: case SSH_CHANNEL_X11_OPEN:
464: return 1;
465: case SSH_CHANNEL_INPUT_DRAINING:
466: case SSH_CHANNEL_OUTPUT_DRAINING:
467: if (!compat13)
468: fatal("cannot happen: OUT_DRAIN");
469: return 1;
470: default:
471: fatal("channel_still_open: bad channel type %d", c->type);
472: /* NOTREACHED */
473: }
474: }
475: return 0;
476: }
477:
478: /* Returns the id of an open channel suitable for keepaliving */
479:
480: int
1.142 itojun 481: channel_find_open(void)
1.121 markus 482: {
483: int i;
484: Channel *c;
485:
486: for (i = 0; i < channels_alloc; i++) {
487: c = channels[i];
488: if (c == NULL)
489: continue;
490: switch (c->type) {
491: case SSH_CHANNEL_CLOSED:
492: case SSH_CHANNEL_DYNAMIC:
493: case SSH_CHANNEL_X11_LISTENER:
494: case SSH_CHANNEL_PORT_LISTENER:
495: case SSH_CHANNEL_RPORT_LISTENER:
496: case SSH_CHANNEL_OPENING:
497: case SSH_CHANNEL_CONNECTING:
498: case SSH_CHANNEL_ZOMBIE:
499: continue;
500: case SSH_CHANNEL_LARVAL:
501: case SSH_CHANNEL_AUTH_SOCKET:
502: case SSH_CHANNEL_OPEN:
503: case SSH_CHANNEL_X11_OPEN:
504: return i;
505: case SSH_CHANNEL_INPUT_DRAINING:
506: case SSH_CHANNEL_OUTPUT_DRAINING:
507: if (!compat13)
508: fatal("cannot happen: OUT_DRAIN");
509: return i;
510: default:
511: fatal("channel_find_open: bad channel type %d", c->type);
512: /* NOTREACHED */
513: }
514: }
515: return -1;
516: }
517:
518:
519: /*
520: * Returns a message describing the currently open forwarded connections,
521: * suitable for sending to the client. The message contains crlf pairs for
522: * newlines.
523: */
524:
525: char *
1.142 itojun 526: channel_open_message(void)
1.121 markus 527: {
528: Buffer buffer;
529: Channel *c;
530: char buf[1024], *cp;
531: int i;
532:
533: buffer_init(&buffer);
534: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
535: buffer_append(&buffer, buf, strlen(buf));
536: for (i = 0; i < channels_alloc; i++) {
537: c = channels[i];
538: if (c == NULL)
539: continue;
540: switch (c->type) {
541: case SSH_CHANNEL_X11_LISTENER:
542: case SSH_CHANNEL_PORT_LISTENER:
543: case SSH_CHANNEL_RPORT_LISTENER:
544: case SSH_CHANNEL_CLOSED:
545: case SSH_CHANNEL_AUTH_SOCKET:
546: case SSH_CHANNEL_ZOMBIE:
547: continue;
548: case SSH_CHANNEL_LARVAL:
549: case SSH_CHANNEL_OPENING:
550: case SSH_CHANNEL_CONNECTING:
551: case SSH_CHANNEL_DYNAMIC:
552: case SSH_CHANNEL_OPEN:
553: case SSH_CHANNEL_X11_OPEN:
554: case SSH_CHANNEL_INPUT_DRAINING:
555: case SSH_CHANNEL_OUTPUT_DRAINING:
556: snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
557: c->self, c->remote_name,
558: c->type, c->remote_id,
559: c->istate, buffer_len(&c->input),
560: c->ostate, buffer_len(&c->output),
561: c->rfd, c->wfd);
562: buffer_append(&buffer, buf, strlen(buf));
563: continue;
564: default:
565: fatal("channel_open_message: bad channel type %d", c->type);
566: /* NOTREACHED */
567: }
568: }
569: buffer_append(&buffer, "\0", 1);
570: cp = xstrdup(buffer_ptr(&buffer));
571: buffer_free(&buffer);
572: return cp;
573: }
574:
575: void
576: channel_send_open(int id)
577: {
578: Channel *c = channel_lookup(id);
579: if (c == NULL) {
580: log("channel_send_open: %d: bad id", id);
581: return;
582: }
583: debug("send channel open %d", id);
584: packet_start(SSH2_MSG_CHANNEL_OPEN);
585: packet_put_cstring(c->ctype);
586: packet_put_int(c->self);
587: packet_put_int(c->local_window);
588: packet_put_int(c->local_maxpacket);
589: packet_send();
590: }
591:
592: void
593: channel_request(int id, char *service, int wantconfirm)
594: {
595: channel_request_start(id, service, wantconfirm);
596: packet_send();
597: debug("channel request %d: %s", id, service) ;
598: }
599: void
600: channel_request_start(int id, char *service, int wantconfirm)
601: {
602: Channel *c = channel_lookup(id);
603: if (c == NULL) {
604: log("channel_request: %d: bad id", id);
605: return;
606: }
607: packet_start(SSH2_MSG_CHANNEL_REQUEST);
608: packet_put_int(c->remote_id);
609: packet_put_cstring(service);
610: packet_put_char(wantconfirm);
611: }
612: void
613: channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
614: {
615: Channel *c = channel_lookup(id);
616: if (c == NULL) {
617: log("channel_register_callback: %d: bad id", id);
618: return;
619: }
620: c->cb_event = mtype;
621: c->cb_fn = fn;
622: c->cb_arg = arg;
623: }
624: void
625: channel_register_cleanup(int id, channel_callback_fn *fn)
626: {
627: Channel *c = channel_lookup(id);
628: if (c == NULL) {
629: log("channel_register_cleanup: %d: bad id", id);
630: return;
631: }
1.131 markus 632: c->detach_user = fn;
1.121 markus 633: }
634: void
635: channel_cancel_cleanup(int id)
636: {
637: Channel *c = channel_lookup(id);
638: if (c == NULL) {
639: log("channel_cancel_cleanup: %d: bad id", id);
640: return;
1.52 markus 641: }
1.131 markus 642: c->detach_user = NULL;
1.121 markus 643: }
644: void
645: channel_register_filter(int id, channel_filter_fn *fn)
646: {
647: Channel *c = channel_lookup(id);
648: if (c == NULL) {
649: log("channel_register_filter: %d: bad id", id);
650: return;
1.52 markus 651: }
1.121 markus 652: c->input_filter = fn;
1.52 markus 653: }
654:
1.49 markus 655: void
1.121 markus 656: channel_set_fds(int id, int rfd, int wfd, int efd,
657: int extusage, int nonblock)
1.1 deraadt 658: {
1.121 markus 659: Channel *c = channel_lookup(id);
660: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
661: fatal("channel_activate for non-larval channel %d.", id);
662: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
663: c->type = SSH_CHANNEL_OPEN;
664: /* XXX window size? */
665: c->local_window = c->local_window_max = c->local_maxpacket * 2;
666: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
667: packet_put_int(c->remote_id);
668: packet_put_int(c->local_window);
669: packet_send();
1.1 deraadt 670: }
671:
1.27 markus 672: /*
1.41 markus 673: * 'channel_pre*' are called just before select() to add any bits relevant to
674: * channels in the select bitmasks.
675: */
676: /*
677: * 'channel_post*': perform any appropriate operations for channels which
678: * have events pending.
1.27 markus 679: */
1.41 markus 680: typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
681: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
682: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
683:
1.127 itojun 684: static void
1.41 markus 685: channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
686: {
687: FD_SET(c->sock, readset);
688: }
689:
1.127 itojun 690: static void
1.75 markus 691: channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
692: {
693: debug3("channel %d: waiting for connection", c->self);
694: FD_SET(c->sock, writeset);
695: }
696:
1.127 itojun 697: static void
1.41 markus 698: channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
699: {
700: if (buffer_len(&c->input) < packet_get_maxsize())
701: FD_SET(c->sock, readset);
702: if (buffer_len(&c->output) > 0)
703: FD_SET(c->sock, writeset);
704: }
1.1 deraadt 705:
1.127 itojun 706: static void
1.157 markus 707: channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 708: {
1.157 markus 709: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 710:
1.44 markus 711: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 712: limit > 0 &&
713: buffer_len(&c->input) < limit)
1.44 markus 714: FD_SET(c->rfd, readset);
715: if (c->ostate == CHAN_OUTPUT_OPEN ||
716: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
717: if (buffer_len(&c->output) > 0) {
718: FD_SET(c->wfd, writeset);
719: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
720: chan_obuf_empty(c);
721: }
722: }
723: /** XXX check close conditions, too */
1.157 markus 724: if (compat20 && c->efd != -1) {
1.44 markus 725: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
726: buffer_len(&c->extended) > 0)
727: FD_SET(c->efd, writeset);
728: else if (c->extended_usage == CHAN_EXTENDED_READ &&
729: buffer_len(&c->extended) < c->remote_window)
730: FD_SET(c->efd, readset);
731: }
732: }
733:
1.127 itojun 734: static void
1.41 markus 735: channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
736: {
737: if (buffer_len(&c->input) == 0) {
738: packet_start(SSH_MSG_CHANNEL_CLOSE);
739: packet_put_int(c->remote_id);
740: packet_send();
741: c->type = SSH_CHANNEL_CLOSED;
1.105 markus 742: debug("channel %d: closing after input drain.", c->self);
1.41 markus 743: }
744: }
745:
1.127 itojun 746: static void
1.41 markus 747: channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
748: {
749: if (buffer_len(&c->output) == 0)
1.113 markus 750: chan_mark_dead(c);
1.49 markus 751: else
1.41 markus 752: FD_SET(c->sock, writeset);
753: }
754:
755: /*
756: * This is a special state for X11 authentication spoofing. An opened X11
757: * connection (when authentication spoofing is being done) remains in this
758: * state until the first packet has been completely read. The authentication
759: * data in that packet is then substituted by the real data if it matches the
760: * fake data, and the channel is put into normal mode.
1.51 markus 761: * XXX All this happens at the client side.
1.121 markus 762: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 763: */
1.127 itojun 764: static int
1.121 markus 765: x11_open_helper(Buffer *b)
1.1 deraadt 766: {
1.77 markus 767: u_char *ucp;
768: u_int proto_len, data_len;
1.25 markus 769:
1.41 markus 770: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 771: if (buffer_len(b) < 12)
1.41 markus 772: return 0;
773:
774: /* Parse the lengths of variable-length fields. */
1.155 stevesk 775: ucp = buffer_ptr(b);
1.41 markus 776: if (ucp[0] == 0x42) { /* Byte order MSB first. */
777: proto_len = 256 * ucp[6] + ucp[7];
778: data_len = 256 * ucp[8] + ucp[9];
779: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
780: proto_len = ucp[6] + 256 * ucp[7];
781: data_len = ucp[8] + 256 * ucp[9];
782: } else {
783: debug("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 784: ucp[0]);
1.41 markus 785: return -1;
786: }
787:
788: /* Check if the whole packet is in buffer. */
1.121 markus 789: if (buffer_len(b) <
1.41 markus 790: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
791: return 0;
792:
793: /* Check if authentication protocol matches. */
794: if (proto_len != strlen(x11_saved_proto) ||
795: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
796: debug("X11 connection uses different authentication protocol.");
797: return -1;
798: }
799: /* Check if authentication data matches our fake data. */
800: if (data_len != x11_fake_data_len ||
801: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
802: x11_fake_data, x11_fake_data_len) != 0) {
803: debug("X11 auth data does not match fake data.");
804: return -1;
805: }
806: /* Check fake data length */
807: if (x11_fake_data_len != x11_saved_data_len) {
808: error("X11 fake_data_len %d != saved_data_len %d",
809: x11_fake_data_len, x11_saved_data_len);
810: return -1;
811: }
812: /*
813: * Received authentication protocol and data match
814: * our fake data. Substitute the fake data with real
815: * data.
816: */
817: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
818: x11_saved_data, x11_saved_data_len);
819: return 1;
820: }
821:
1.127 itojun 822: static void
1.41 markus 823: channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
824: {
1.121 markus 825: int ret = x11_open_helper(&c->output);
1.41 markus 826: if (ret == 1) {
827: /* Start normal processing for the channel. */
828: c->type = SSH_CHANNEL_OPEN;
1.47 markus 829: channel_pre_open_13(c, readset, writeset);
1.41 markus 830: } else if (ret == -1) {
831: /*
832: * We have received an X11 connection that has bad
833: * authentication information.
834: */
1.98 millert 835: log("X11 connection rejected because of wrong authentication.");
1.41 markus 836: buffer_clear(&c->input);
837: buffer_clear(&c->output);
1.132 markus 838: channel_close_fd(&c->sock);
1.41 markus 839: c->sock = -1;
840: c->type = SSH_CHANNEL_CLOSED;
841: packet_start(SSH_MSG_CHANNEL_CLOSE);
842: packet_put_int(c->remote_id);
843: packet_send();
844: }
845: }
1.25 markus 846:
1.127 itojun 847: static void
1.51 markus 848: channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 849: {
1.121 markus 850: int ret = x11_open_helper(&c->output);
1.133 markus 851:
852: /* c->force_drain = 1; */
853:
1.41 markus 854: if (ret == 1) {
855: c->type = SSH_CHANNEL_OPEN;
1.157 markus 856: channel_pre_open(c, readset, writeset);
1.41 markus 857: } else if (ret == -1) {
1.156 markus 858: log("X11 connection rejected because of wrong authentication.");
1.41 markus 859: debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 860: chan_read_failed(c);
861: buffer_clear(&c->input);
862: chan_ibuf_empty(c);
863: buffer_clear(&c->output);
864: /* for proto v1, the peer will send an IEOF */
865: if (compat20)
866: chan_write_failed(c);
867: else
868: c->type = SSH_CHANNEL_OPEN;
1.41 markus 869: debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
870: }
871: }
1.25 markus 872:
1.104 markus 873: /* try to decode a socks4 header */
1.127 itojun 874: static int
1.104 markus 875: channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
1.103 markus 876: {
877: u_char *p, *host;
1.109 markus 878: int len, have, i, found;
1.148 deraadt 879: char username[256];
1.103 markus 880: struct {
881: u_int8_t version;
882: u_int8_t command;
883: u_int16_t dest_port;
1.104 markus 884: struct in_addr dest_addr;
1.103 markus 885: } s4_req, s4_rsp;
886:
1.104 markus 887: debug2("channel %d: decode socks4", c->self);
1.109 markus 888:
889: have = buffer_len(&c->input);
890: len = sizeof(s4_req);
891: if (have < len)
892: return 0;
893: p = buffer_ptr(&c->input);
894: for (found = 0, i = len; i < have; i++) {
895: if (p[i] == '\0') {
896: found = 1;
897: break;
898: }
899: if (i > 1024) {
900: /* the peer is probably sending garbage */
901: debug("channel %d: decode socks4: too long",
902: c->self);
903: return -1;
904: }
905: }
906: if (!found)
907: return 0;
1.103 markus 908: buffer_get(&c->input, (char *)&s4_req.version, 1);
909: buffer_get(&c->input, (char *)&s4_req.command, 1);
910: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 911: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 912: have = buffer_len(&c->input);
1.103 markus 913: p = buffer_ptr(&c->input);
914: len = strlen(p);
1.106 markus 915: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 916: if (len > have)
1.104 markus 917: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 918: c->self, len, have);
919: strlcpy(username, p, sizeof(username));
920: buffer_consume(&c->input, len);
921: buffer_consume(&c->input, 1); /* trailing '\0' */
922:
1.104 markus 923: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 924: strlcpy(c->path, host, sizeof(c->path));
925: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 926:
1.106 markus 927: debug("channel %d: dynamic request: socks4 host %s port %u command %u",
928: c->self, host, c->host_port, s4_req.command);
1.103 markus 929:
1.104 markus 930: if (s4_req.command != 1) {
931: debug("channel %d: cannot handle: socks4 cn %d",
932: c->self, s4_req.command);
933: return -1;
1.103 markus 934: }
1.104 markus 935: s4_rsp.version = 0; /* vn: 0 for reply */
936: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 937: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 938: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.103 markus 939: buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
1.104 markus 940: return 1;
941: }
942:
943: /* dynamic port forwarding */
1.127 itojun 944: static void
1.104 markus 945: channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
946: {
947: u_char *p;
948: int have, ret;
1.103 markus 949:
1.104 markus 950: have = buffer_len(&c->input);
1.137 markus 951: c->delayed = 0;
1.104 markus 952: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 953: /* buffer_dump(&c->input); */
1.104 markus 954: /* check if the fixed size part of the packet is in buffer. */
955: if (have < 4) {
956: /* need more */
957: FD_SET(c->sock, readset);
958: return;
959: }
960: /* try to guess the protocol */
961: p = buffer_ptr(&c->input);
962: switch (p[0]) {
963: case 0x04:
964: ret = channel_decode_socks4(c, readset, writeset);
965: break;
966: default:
967: ret = -1;
968: break;
969: }
970: if (ret < 0) {
1.113 markus 971: chan_mark_dead(c);
1.104 markus 972: } else if (ret == 0) {
973: debug2("channel %d: pre_dynamic: need more", c->self);
974: /* need more */
975: FD_SET(c->sock, readset);
976: } else {
977: /* switch to the next state */
978: c->type = SSH_CHANNEL_OPENING;
979: port_open_helper(c, "direct-tcpip");
980: }
1.103 markus 981: }
982:
1.41 markus 983: /* This is our fake X11 server socket. */
1.127 itojun 984: static void
1.41 markus 985: channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
986: {
1.113 markus 987: Channel *nc;
1.41 markus 988: struct sockaddr addr;
1.162 stevesk 989: int newsock;
1.41 markus 990: socklen_t addrlen;
1.85 markus 991: char buf[16384], *remote_ipaddr;
1.51 markus 992: int remote_port;
1.25 markus 993:
1.41 markus 994: if (FD_ISSET(c->sock, readset)) {
995: debug("X11 connection requested.");
996: addrlen = sizeof(addr);
997: newsock = accept(c->sock, &addr, &addrlen);
1.149 markus 998: if (c->single_connection) {
999: debug("single_connection: closing X11 listener.");
1000: channel_close_fd(&c->sock);
1001: chan_mark_dead(c);
1002: }
1.41 markus 1003: if (newsock < 0) {
1004: error("accept: %.100s", strerror(errno));
1005: return;
1006: }
1.162 stevesk 1007: set_nodelay(newsock);
1.85 markus 1008: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1009: remote_port = get_peer_port(newsock);
1.41 markus 1010: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1011: remote_ipaddr, remote_port);
1.51 markus 1012:
1.113 markus 1013: nc = channel_new("accepted x11 socket",
1.51 markus 1014: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1015: c->local_window_max, c->local_maxpacket,
1.71 markus 1016: 0, xstrdup(buf), 1);
1.113 markus 1017: if (nc == NULL) {
1018: close(newsock);
1019: xfree(remote_ipaddr);
1020: return;
1021: }
1.51 markus 1022: if (compat20) {
1023: packet_start(SSH2_MSG_CHANNEL_OPEN);
1024: packet_put_cstring("x11");
1.113 markus 1025: packet_put_int(nc->self);
1.149 markus 1026: packet_put_int(nc->local_window_max);
1027: packet_put_int(nc->local_maxpacket);
1.85 markus 1028: /* originator ipaddr and port */
1029: packet_put_cstring(remote_ipaddr);
1.57 markus 1030: if (datafellows & SSH_BUG_X11FWD) {
1031: debug("ssh2 x11 bug compat mode");
1032: } else {
1033: packet_put_int(remote_port);
1034: }
1.51 markus 1035: packet_send();
1036: } else {
1037: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1038: packet_put_int(nc->self);
1.121 markus 1039: if (packet_get_protocol_flags() &
1040: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1041: packet_put_cstring(buf);
1.51 markus 1042: packet_send();
1043: }
1.85 markus 1044: xfree(remote_ipaddr);
1.41 markus 1045: }
1046: }
1.25 markus 1047:
1.127 itojun 1048: static void
1.103 markus 1049: port_open_helper(Channel *c, char *rtype)
1050: {
1051: int direct;
1052: char buf[1024];
1053: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1054: u_short remote_port = get_peer_port(c->sock);
1055:
1056: direct = (strcmp(rtype, "direct-tcpip") == 0);
1057:
1058: snprintf(buf, sizeof buf,
1059: "%s: listening port %d for %.100s port %d, "
1060: "connect from %.200s port %d",
1061: rtype, c->listening_port, c->path, c->host_port,
1062: remote_ipaddr, remote_port);
1063:
1064: xfree(c->remote_name);
1065: c->remote_name = xstrdup(buf);
1066:
1067: if (compat20) {
1068: packet_start(SSH2_MSG_CHANNEL_OPEN);
1069: packet_put_cstring(rtype);
1070: packet_put_int(c->self);
1071: packet_put_int(c->local_window_max);
1072: packet_put_int(c->local_maxpacket);
1073: if (direct) {
1074: /* target host, port */
1075: packet_put_cstring(c->path);
1076: packet_put_int(c->host_port);
1077: } else {
1078: /* listen address, port */
1079: packet_put_cstring(c->path);
1080: packet_put_int(c->listening_port);
1081: }
1082: /* originator host and port */
1083: packet_put_cstring(remote_ipaddr);
1084: packet_put_int(remote_port);
1085: packet_send();
1086: } else {
1087: packet_start(SSH_MSG_PORT_OPEN);
1088: packet_put_int(c->self);
1089: packet_put_cstring(c->path);
1090: packet_put_int(c->host_port);
1.121 markus 1091: if (packet_get_protocol_flags() &
1092: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1093: packet_put_cstring(c->remote_name);
1094: packet_send();
1095: }
1096: xfree(remote_ipaddr);
1097: }
1098:
1.41 markus 1099: /*
1100: * This socket is listening for connections to a forwarded TCP/IP port.
1101: */
1.127 itojun 1102: static void
1.41 markus 1103: channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1104: {
1.103 markus 1105: Channel *nc;
1.41 markus 1106: struct sockaddr addr;
1.113 markus 1107: int newsock, nextstate;
1.41 markus 1108: socklen_t addrlen;
1.103 markus 1109: char *rtype;
1.73 markus 1110:
1.41 markus 1111: if (FD_ISSET(c->sock, readset)) {
1112: debug("Connection to port %d forwarding "
1113: "to %.100s port %d requested.",
1114: c->listening_port, c->path, c->host_port);
1.103 markus 1115:
1.137 markus 1116: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1117: nextstate = SSH_CHANNEL_OPENING;
1118: rtype = "forwarded-tcpip";
1119: } else {
1120: if (c->host_port == 0) {
1121: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1122: rtype = "dynamic-tcpip";
1.137 markus 1123: } else {
1124: nextstate = SSH_CHANNEL_OPENING;
1125: rtype = "direct-tcpip";
1126: }
1127: }
1.103 markus 1128:
1.41 markus 1129: addrlen = sizeof(addr);
1130: newsock = accept(c->sock, &addr, &addrlen);
1131: if (newsock < 0) {
1132: error("accept: %.100s", strerror(errno));
1133: return;
1134: }
1.113 markus 1135: nc = channel_new(rtype,
1.103 markus 1136: nextstate, newsock, newsock, -1,
1.41 markus 1137: c->local_window_max, c->local_maxpacket,
1.103 markus 1138: 0, xstrdup(rtype), 1);
1139: if (nc == NULL) {
1.113 markus 1140: error("channel_post_port_listener: no new channel:");
1141: close(newsock);
1.103 markus 1142: return;
1.41 markus 1143: }
1.103 markus 1144: nc->listening_port = c->listening_port;
1145: nc->host_port = c->host_port;
1146: strlcpy(nc->path, c->path, sizeof(nc->path));
1147:
1.137 markus 1148: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1149: /*
1150: * do not call the channel_post handler until
1151: * this flag has been reset by a pre-handler.
1152: * otherwise the FD_ISSET calls might overflow
1153: */
1154: nc->delayed = 1;
1155: } else {
1.103 markus 1156: port_open_helper(nc, rtype);
1.137 markus 1157: }
1.41 markus 1158: }
1159: }
1.25 markus 1160:
1.41 markus 1161: /*
1162: * This is the authentication agent socket listening for connections from
1163: * clients.
1164: */
1.127 itojun 1165: static void
1.41 markus 1166: channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1167: {
1.113 markus 1168: Channel *nc;
1.121 markus 1169: char *name;
1.113 markus 1170: int newsock;
1.41 markus 1171: struct sockaddr addr;
1172: socklen_t addrlen;
1.25 markus 1173:
1.41 markus 1174: if (FD_ISSET(c->sock, readset)) {
1175: addrlen = sizeof(addr);
1176: newsock = accept(c->sock, &addr, &addrlen);
1177: if (newsock < 0) {
1178: error("accept from auth socket: %.100s", strerror(errno));
1179: return;
1180: }
1.121 markus 1181: name = xstrdup("accepted auth socket");
1.113 markus 1182: nc = channel_new("accepted auth socket",
1.73 markus 1183: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1184: c->local_window_max, c->local_maxpacket,
1.121 markus 1185: 0, name, 1);
1.113 markus 1186: if (nc == NULL) {
1187: error("channel_post_auth_listener: channel_new failed");
1.121 markus 1188: xfree(name);
1.113 markus 1189: close(newsock);
1190: }
1.73 markus 1191: if (compat20) {
1192: packet_start(SSH2_MSG_CHANNEL_OPEN);
1193: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1194: packet_put_int(nc->self);
1.73 markus 1195: packet_put_int(c->local_window_max);
1196: packet_put_int(c->local_maxpacket);
1197: } else {
1198: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1199: packet_put_int(nc->self);
1.73 markus 1200: }
1.41 markus 1201: packet_send();
1202: }
1203: }
1.25 markus 1204:
1.127 itojun 1205: static void
1.75 markus 1206: channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1207: {
1.114 markus 1208: int err = 0;
1.129 stevesk 1209: socklen_t sz = sizeof(err);
1.114 markus 1210:
1.75 markus 1211: if (FD_ISSET(c->sock, writeset)) {
1.114 markus 1212: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
1213: &sz) < 0) {
1214: err = errno;
1215: error("getsockopt SO_ERROR failed");
1216: }
1217: if (err == 0) {
1218: debug("channel %d: connected", c->self);
1219: c->type = SSH_CHANNEL_OPEN;
1220: if (compat20) {
1221: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1222: packet_put_int(c->remote_id);
1223: packet_put_int(c->self);
1224: packet_put_int(c->local_window);
1225: packet_put_int(c->local_maxpacket);
1226: } else {
1227: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1228: packet_put_int(c->remote_id);
1229: packet_put_int(c->self);
1230: }
1.75 markus 1231: } else {
1.114 markus 1232: debug("channel %d: not connected: %s",
1233: c->self, strerror(err));
1234: if (compat20) {
1235: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1236: packet_put_int(c->remote_id);
1237: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1238: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1239: packet_put_cstring(strerror(err));
1240: packet_put_cstring("");
1241: }
1.75 markus 1242: } else {
1.114 markus 1243: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1244: packet_put_int(c->remote_id);
1.75 markus 1245: }
1.114 markus 1246: chan_mark_dead(c);
1.75 markus 1247: }
1.114 markus 1248: packet_send();
1.75 markus 1249: }
1250: }
1251:
1.127 itojun 1252: static int
1.41 markus 1253: channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1254: {
1255: char buf[16*1024];
1256: int len;
1.25 markus 1257:
1.118 markus 1258: if (c->rfd != -1 &&
1.41 markus 1259: FD_ISSET(c->rfd, readset)) {
1260: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1261: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1262: return 1;
1.41 markus 1263: if (len <= 0) {
1.51 markus 1264: debug("channel %d: read<=0 rfd %d len %d",
1.41 markus 1265: c->self, c->rfd, len);
1.104 markus 1266: if (c->type != SSH_CHANNEL_OPEN) {
1267: debug("channel %d: not open", c->self);
1.113 markus 1268: chan_mark_dead(c);
1.103 markus 1269: return -1;
1.104 markus 1270: } else if (compat13) {
1.158 markus 1271: buffer_clear(&c->output);
1.41 markus 1272: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.121 markus 1273: debug("channel %d: input draining.", c->self);
1.25 markus 1274: } else {
1.41 markus 1275: chan_read_failed(c);
1.25 markus 1276: }
1.41 markus 1277: return -1;
1278: }
1.143 deraadt 1279: if (c->input_filter != NULL) {
1.66 markus 1280: if (c->input_filter(c, buf, len) == -1) {
1.105 markus 1281: debug("channel %d: filter stops", c->self);
1.65 markus 1282: chan_read_failed(c);
1283: }
1284: } else {
1285: buffer_append(&c->input, buf, len);
1286: }
1.41 markus 1287: }
1288: return 1;
1289: }
1.127 itojun 1290: static int
1.41 markus 1291: channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1292: {
1.95 markus 1293: struct termios tio;
1.134 markus 1294: u_char *data;
1295: u_int dlen;
1.41 markus 1296: int len;
1.25 markus 1297:
1.41 markus 1298: /* Send buffered output data to the socket. */
1.118 markus 1299: if (c->wfd != -1 &&
1.41 markus 1300: FD_ISSET(c->wfd, writeset) &&
1301: buffer_len(&c->output) > 0) {
1.134 markus 1302: data = buffer_ptr(&c->output);
1303: dlen = buffer_len(&c->output);
1304: len = write(c->wfd, data, dlen);
1.53 markus 1305: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1306: return 1;
1.41 markus 1307: if (len <= 0) {
1.104 markus 1308: if (c->type != SSH_CHANNEL_OPEN) {
1309: debug("channel %d: not open", c->self);
1.113 markus 1310: chan_mark_dead(c);
1.104 markus 1311: return -1;
1312: } else if (compat13) {
1.158 markus 1313: buffer_clear(&c->output);
1.121 markus 1314: debug("channel %d: input draining.", c->self);
1.41 markus 1315: c->type = SSH_CHANNEL_INPUT_DRAINING;
1316: } else {
1317: chan_write_failed(c);
1318: }
1319: return -1;
1.91 markus 1320: }
1.134 markus 1321: if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
1.91 markus 1322: if (tcgetattr(c->wfd, &tio) == 0 &&
1323: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1324: /*
1325: * Simulate echo to reduce the impact of
1.96 markus 1326: * traffic analysis. We need to match the
1.95 markus 1327: * size of a SSH2_MSG_CHANNEL_DATA message
1328: * (4 byte channel id + data)
1.91 markus 1329: */
1.95 markus 1330: packet_send_ignore(4 + len);
1.91 markus 1331: packet_send();
1332: }
1.25 markus 1333: }
1.41 markus 1334: buffer_consume(&c->output, len);
1.44 markus 1335: if (compat20 && len > 0) {
1336: c->local_consumed += len;
1337: }
1338: }
1339: return 1;
1340: }
1.127 itojun 1341: static int
1.44 markus 1342: channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1343: {
1344: char buf[16*1024];
1345: int len;
1346:
1.45 markus 1347: /** XXX handle drain efd, too */
1.44 markus 1348: if (c->efd != -1) {
1349: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1350: FD_ISSET(c->efd, writeset) &&
1351: buffer_len(&c->extended) > 0) {
1352: len = write(c->efd, buffer_ptr(&c->extended),
1353: buffer_len(&c->extended));
1.70 markus 1354: debug2("channel %d: written %d to efd %d",
1.44 markus 1355: c->self, len, c->efd);
1.93 markus 1356: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1357: return 1;
1358: if (len <= 0) {
1359: debug2("channel %d: closing write-efd %d",
1360: c->self, c->efd);
1.132 markus 1361: channel_close_fd(&c->efd);
1.93 markus 1362: } else {
1.44 markus 1363: buffer_consume(&c->extended, len);
1364: c->local_consumed += len;
1365: }
1366: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1367: FD_ISSET(c->efd, readset)) {
1368: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1369: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1370: c->self, len, c->efd);
1.93 markus 1371: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1372: return 1;
1373: if (len <= 0) {
1374: debug2("channel %d: closing read-efd %d",
1.45 markus 1375: c->self, c->efd);
1.132 markus 1376: channel_close_fd(&c->efd);
1.93 markus 1377: } else {
1.44 markus 1378: buffer_append(&c->extended, buf, len);
1.93 markus 1379: }
1.44 markus 1380: }
1381: }
1382: return 1;
1383: }
1.127 itojun 1384: static int
1.93 markus 1385: channel_check_window(Channel *c)
1.44 markus 1386: {
1.104 markus 1387: if (c->type == SSH_CHANNEL_OPEN &&
1388: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.44 markus 1389: c->local_window < c->local_window_max/2 &&
1390: c->local_consumed > 0) {
1391: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1392: packet_put_int(c->remote_id);
1393: packet_put_int(c->local_consumed);
1394: packet_send();
1.70 markus 1395: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1396: c->self, c->local_window,
1397: c->local_consumed);
1398: c->local_window += c->local_consumed;
1399: c->local_consumed = 0;
1.1 deraadt 1400: }
1.41 markus 1401: return 1;
1.1 deraadt 1402: }
1403:
1.127 itojun 1404: static void
1.157 markus 1405: channel_post_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 1406: {
1.137 markus 1407: if (c->delayed)
1408: return;
1.41 markus 1409: channel_handle_rfd(c, readset, writeset);
1410: channel_handle_wfd(c, readset, writeset);
1.157 markus 1411: if (!compat20)
1.137 markus 1412: return;
1.44 markus 1413: channel_handle_efd(c, readset, writeset);
1.93 markus 1414: channel_check_window(c);
1.44 markus 1415: }
1416:
1.127 itojun 1417: static void
1.41 markus 1418: channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1.1 deraadt 1419: {
1.41 markus 1420: int len;
1421: /* Send buffered output data to the socket. */
1422: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1423: len = write(c->sock, buffer_ptr(&c->output),
1424: buffer_len(&c->output));
1425: if (len <= 0)
1.158 markus 1426: buffer_clear(&c->output);
1.41 markus 1427: else
1428: buffer_consume(&c->output, len);
1429: }
1430: }
1.25 markus 1431:
1.127 itojun 1432: static void
1.44 markus 1433: channel_handler_init_20(void)
1434: {
1.157 markus 1435: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1436: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1437: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1438: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1439: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1440: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1441: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1442: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1443:
1.157 markus 1444: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1445: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1446: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1447: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1448: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1449: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1450: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1451: }
1452:
1.127 itojun 1453: static void
1.41 markus 1454: channel_handler_init_13(void)
1455: {
1456: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1457: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1458: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1459: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1460: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1461: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1462: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1463: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1464: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1465:
1.157 markus 1466: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1467: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1468: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1469: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1470: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1471: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1472: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1473: }
1.25 markus 1474:
1.127 itojun 1475: static void
1.41 markus 1476: channel_handler_init_15(void)
1477: {
1.157 markus 1478: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1479: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1480: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1481: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1482: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1483: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1484: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1485:
1.41 markus 1486: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1487: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1488: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1489: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1490: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1491: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1492: }
1.27 markus 1493:
1.127 itojun 1494: static void
1.41 markus 1495: channel_handler_init(void)
1496: {
1497: int i;
1.148 deraadt 1498: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1499: channel_pre[i] = NULL;
1500: channel_post[i] = NULL;
1501: }
1.44 markus 1502: if (compat20)
1503: channel_handler_init_20();
1504: else if (compat13)
1.41 markus 1505: channel_handler_init_13();
1506: else
1507: channel_handler_init_15();
1508: }
1.25 markus 1509:
1.140 markus 1510: /* gc dead channels */
1511: static void
1512: channel_garbage_collect(Channel *c)
1513: {
1514: if (c == NULL)
1515: return;
1516: if (c->detach_user != NULL) {
1517: if (!chan_is_dead(c, 0))
1518: return;
1519: debug("channel %d: gc: notify user", c->self);
1520: c->detach_user(c->self, NULL);
1521: /* if we still have a callback */
1522: if (c->detach_user != NULL)
1523: return;
1524: debug("channel %d: gc: user detached", c->self);
1525: }
1526: if (!chan_is_dead(c, 1))
1527: return;
1528: debug("channel %d: garbage collecting", c->self);
1529: channel_free(c);
1530: }
1531:
1.127 itojun 1532: static void
1.41 markus 1533: channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1534: {
1535: static int did_init = 0;
1536: int i;
1537: Channel *c;
1.25 markus 1538:
1.41 markus 1539: if (!did_init) {
1540: channel_handler_init();
1541: did_init = 1;
1542: }
1543: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1544: c = channels[i];
1545: if (c == NULL)
1.41 markus 1546: continue;
1.118 markus 1547: if (ftab[c->type] != NULL)
1548: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1549: channel_garbage_collect(c);
1.1 deraadt 1550: }
1551: }
1552:
1.121 markus 1553: /*
1554: * Allocate/update select bitmasks and add any bits relevant to channels in
1555: * select bitmasks.
1556: */
1.49 markus 1557: void
1.100 markus 1558: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.132 markus 1559: int *nallocp, int rekeying)
1.41 markus 1560: {
1.84 markus 1561: int n;
1562: u_int sz;
1563:
1564: n = MAX(*maxfdp, channel_max_fd);
1565:
1566: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.132 markus 1567: /* perhaps check sz < nalloc/2 and shrink? */
1568: if (*readsetp == NULL || sz > *nallocp) {
1569: *readsetp = xrealloc(*readsetp, sz);
1570: *writesetp = xrealloc(*writesetp, sz);
1571: *nallocp = sz;
1.84 markus 1572: }
1.132 markus 1573: *maxfdp = n;
1.84 markus 1574: memset(*readsetp, 0, sz);
1575: memset(*writesetp, 0, sz);
1576:
1.100 markus 1577: if (!rekeying)
1578: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1579: }
1580:
1.121 markus 1581: /*
1582: * After select, perform any appropriate operations for channels which have
1583: * events pending.
1584: */
1.49 markus 1585: void
1.41 markus 1586: channel_after_select(fd_set * readset, fd_set * writeset)
1587: {
1588: channel_handler(channel_post, readset, writeset);
1589: }
1590:
1.121 markus 1591:
1.84 markus 1592: /* If there is data to send to the connection, enqueue some of it now. */
1.1 deraadt 1593:
1.49 markus 1594: void
1.142 itojun 1595: channel_output_poll(void)
1.1 deraadt 1596: {
1.25 markus 1597: int len, i;
1.41 markus 1598: Channel *c;
1.1 deraadt 1599:
1.25 markus 1600: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1601: c = channels[i];
1602: if (c == NULL)
1603: continue;
1.37 markus 1604:
1.121 markus 1605: /*
1606: * We are only interested in channels that can have buffered
1607: * incoming data.
1608: */
1.37 markus 1609: if (compat13) {
1.41 markus 1610: if (c->type != SSH_CHANNEL_OPEN &&
1611: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1612: continue;
1613: } else {
1.41 markus 1614: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1615: continue;
1616: }
1.46 markus 1617: if (compat20 &&
1618: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1619: /* XXX is this true? */
1.140 markus 1620: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1621: continue;
1622: }
1.25 markus 1623:
1624: /* Get the amount of buffered data for this channel. */
1.93 markus 1625: if ((c->istate == CHAN_INPUT_OPEN ||
1626: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1627: (len = buffer_len(&c->input)) > 0) {
1.121 markus 1628: /*
1629: * Send some data for the other side over the secure
1630: * connection.
1631: */
1.44 markus 1632: if (compat20) {
1633: if (len > c->remote_window)
1634: len = c->remote_window;
1635: if (len > c->remote_maxpacket)
1636: len = c->remote_maxpacket;
1.25 markus 1637: } else {
1.44 markus 1638: if (packet_is_interactive()) {
1639: if (len > 1024)
1640: len = 512;
1641: } else {
1642: /* Keep the packets at reasonable size. */
1643: if (len > packet_get_maxsize()/2)
1644: len = packet_get_maxsize()/2;
1645: }
1.25 markus 1646: }
1.41 markus 1647: if (len > 0) {
1.44 markus 1648: packet_start(compat20 ?
1649: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1650: packet_put_int(c->remote_id);
1651: packet_put_string(buffer_ptr(&c->input), len);
1652: packet_send();
1653: buffer_consume(&c->input, len);
1654: c->remote_window -= len;
1655: }
1656: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1657: if (compat13)
1658: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1659: /*
1660: * input-buffer is empty and read-socket shutdown:
1661: * tell peer, that we will not send more data: send IEOF
1662: */
1.41 markus 1663: chan_ibuf_empty(c);
1.25 markus 1664: }
1.44 markus 1665: /* Send extended data, i.e. stderr */
1666: if (compat20 &&
1667: c->remote_window > 0 &&
1668: (len = buffer_len(&c->extended)) > 0 &&
1669: c->extended_usage == CHAN_EXTENDED_READ) {
1.93 markus 1670: debug2("channel %d: rwin %d elen %d euse %d",
1671: c->self, c->remote_window, buffer_len(&c->extended),
1672: c->extended_usage);
1.44 markus 1673: if (len > c->remote_window)
1674: len = c->remote_window;
1675: if (len > c->remote_maxpacket)
1676: len = c->remote_maxpacket;
1677: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1678: packet_put_int(c->remote_id);
1679: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1680: packet_put_string(buffer_ptr(&c->extended), len);
1681: packet_send();
1682: buffer_consume(&c->extended, len);
1683: c->remote_window -= len;
1.93 markus 1684: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1685: }
1.25 markus 1686: }
1.1 deraadt 1687: }
1688:
1.121 markus 1689:
1690: /* -- protocol input */
1.1 deraadt 1691:
1.49 markus 1692: void
1.154 markus 1693: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1694: {
1.37 markus 1695: int id;
1.25 markus 1696: char *data;
1.77 markus 1697: u_int data_len;
1.41 markus 1698: Channel *c;
1.25 markus 1699:
1700: /* Get the channel number and verify it. */
1.37 markus 1701: id = packet_get_int();
1.41 markus 1702: c = channel_lookup(id);
1703: if (c == NULL)
1.37 markus 1704: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 1705:
1706: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 1707: if (c->type != SSH_CHANNEL_OPEN &&
1708: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 1709: return;
1710:
1711: /* same for protocol 1.5 if output end is no longer open */
1.41 markus 1712: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
1.25 markus 1713: return;
1714:
1715: /* Get the data. */
1716: data = packet_get_string(&data_len);
1.41 markus 1717:
1.143 deraadt 1718: if (compat20) {
1.44 markus 1719: if (data_len > c->local_maxpacket) {
1720: log("channel %d: rcvd big packet %d, maxpack %d",
1721: c->self, data_len, c->local_maxpacket);
1722: }
1723: if (data_len > c->local_window) {
1724: log("channel %d: rcvd too much data %d, win %d",
1725: c->self, data_len, c->local_window);
1726: xfree(data);
1727: return;
1728: }
1729: c->local_window -= data_len;
1730: }
1.152 markus 1731: packet_check_eom();
1.41 markus 1732: buffer_append(&c->output, data, data_len);
1.25 markus 1733: xfree(data);
1.1 deraadt 1734: }
1.121 markus 1735:
1.49 markus 1736: void
1.154 markus 1737: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 1738: {
1739: int id;
1740: int tcode;
1741: char *data;
1.77 markus 1742: u_int data_len;
1.44 markus 1743: Channel *c;
1744:
1745: /* Get the channel number and verify it. */
1746: id = packet_get_int();
1747: c = channel_lookup(id);
1748:
1749: if (c == NULL)
1750: packet_disconnect("Received extended_data for bad channel %d.", id);
1751: if (c->type != SSH_CHANNEL_OPEN) {
1752: log("channel %d: ext data for non open", id);
1753: return;
1754: }
1755: tcode = packet_get_int();
1756: if (c->efd == -1 ||
1757: c->extended_usage != CHAN_EXTENDED_WRITE ||
1758: tcode != SSH2_EXTENDED_DATA_STDERR) {
1759: log("channel %d: bad ext data", c->self);
1760: return;
1761: }
1762: data = packet_get_string(&data_len);
1.152 markus 1763: packet_check_eom();
1.44 markus 1764: if (data_len > c->local_window) {
1765: log("channel %d: rcvd too much extended_data %d, win %d",
1766: c->self, data_len, c->local_window);
1767: xfree(data);
1768: return;
1769: }
1.70 markus 1770: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 1771: c->local_window -= data_len;
1772: buffer_append(&c->extended, data, data_len);
1773: xfree(data);
1774: }
1775:
1.49 markus 1776: void
1.154 markus 1777: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 1778: {
1779: int id;
1780: Channel *c;
1781:
1782: id = packet_get_int();
1.152 markus 1783: packet_check_eom();
1.41 markus 1784: c = channel_lookup(id);
1785: if (c == NULL)
1786: packet_disconnect("Received ieof for nonexistent channel %d.", id);
1787: chan_rcvd_ieof(c);
1.133 markus 1788:
1789: /* XXX force input close */
1.156 markus 1790: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 1791: debug("channel %d: FORCE input drain", c->self);
1792: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 1793: if (buffer_len(&c->input) == 0)
1794: chan_ibuf_empty(c);
1.133 markus 1795: }
1796:
1.41 markus 1797: }
1.1 deraadt 1798:
1.49 markus 1799: void
1.154 markus 1800: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1801: {
1.41 markus 1802: int id;
1803: Channel *c;
1.1 deraadt 1804:
1.41 markus 1805: id = packet_get_int();
1.152 markus 1806: packet_check_eom();
1.41 markus 1807: c = channel_lookup(id);
1808: if (c == NULL)
1809: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 1810:
1811: /*
1812: * Send a confirmation that we have closed the channel and no more
1813: * data is coming for it.
1814: */
1.25 markus 1815: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 1816: packet_put_int(c->remote_id);
1.25 markus 1817: packet_send();
1818:
1.27 markus 1819: /*
1820: * If the channel is in closed state, we have sent a close request,
1821: * and the other side will eventually respond with a confirmation.
1822: * Thus, we cannot free the channel here, because then there would be
1823: * no-one to receive the confirmation. The channel gets freed when
1824: * the confirmation arrives.
1825: */
1.41 markus 1826: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 1827: /*
1828: * Not a closed channel - mark it as draining, which will
1829: * cause it to be freed later.
1830: */
1.158 markus 1831: buffer_clear(&c->input);
1.41 markus 1832: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 1833: }
1.1 deraadt 1834: }
1835:
1.41 markus 1836: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.49 markus 1837: void
1.154 markus 1838: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 1839: {
1840: int id = packet_get_int();
1841: Channel *c = channel_lookup(id);
1.151 markus 1842:
1.152 markus 1843: packet_check_eom();
1.41 markus 1844: if (c == NULL)
1845: packet_disconnect("Received oclose for nonexistent channel %d.", id);
1846: chan_rcvd_oclose(c);
1847: }
1.1 deraadt 1848:
1.49 markus 1849: void
1.154 markus 1850: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1851: {
1.41 markus 1852: int id = packet_get_int();
1853: Channel *c = channel_lookup(id);
1.1 deraadt 1854:
1.152 markus 1855: packet_check_eom();
1.41 markus 1856: if (c == NULL)
1857: packet_disconnect("Received close confirmation for "
1858: "out-of-range channel %d.", id);
1859: if (c->type != SSH_CHANNEL_CLOSED)
1860: packet_disconnect("Received close confirmation for "
1861: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 1862: channel_free(c);
1.1 deraadt 1863: }
1864:
1.49 markus 1865: void
1.154 markus 1866: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1867: {
1.41 markus 1868: int id, remote_id;
1869: Channel *c;
1.1 deraadt 1870:
1.41 markus 1871: id = packet_get_int();
1872: c = channel_lookup(id);
1.25 markus 1873:
1.41 markus 1874: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1875: packet_disconnect("Received open confirmation for "
1876: "non-opening channel %d.", id);
1877: remote_id = packet_get_int();
1.27 markus 1878: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 1879: c->remote_id = remote_id;
1880: c->type = SSH_CHANNEL_OPEN;
1.44 markus 1881:
1882: if (compat20) {
1883: c->remote_window = packet_get_int();
1884: c->remote_maxpacket = packet_get_int();
1885: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1886: debug2("callback start");
1.44 markus 1887: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1888: debug2("callback done");
1.44 markus 1889: }
1890: debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1891: c->remote_window, c->remote_maxpacket);
1892: }
1.152 markus 1893: packet_check_eom();
1.1 deraadt 1894: }
1895:
1.127 itojun 1896: static char *
1.114 markus 1897: reason2txt(int reason)
1898: {
1.143 deraadt 1899: switch (reason) {
1.114 markus 1900: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1901: return "administratively prohibited";
1902: case SSH2_OPEN_CONNECT_FAILED:
1903: return "connect failed";
1904: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1905: return "unknown channel type";
1906: case SSH2_OPEN_RESOURCE_SHORTAGE:
1907: return "resource shortage";
1908: }
1.117 stevesk 1909: return "unknown reason";
1.114 markus 1910: }
1911:
1.49 markus 1912: void
1.154 markus 1913: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1914: {
1.86 markus 1915: int id, reason;
1916: char *msg = NULL, *lang = NULL;
1.41 markus 1917: Channel *c;
1918:
1919: id = packet_get_int();
1920: c = channel_lookup(id);
1.25 markus 1921:
1.41 markus 1922: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1923: packet_disconnect("Received open failure for "
1924: "non-opening channel %d.", id);
1.44 markus 1925: if (compat20) {
1.86 markus 1926: reason = packet_get_int();
1.110 markus 1927: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 1928: msg = packet_get_string(NULL);
1929: lang = packet_get_string(NULL);
1930: }
1.114 markus 1931: log("channel %d: open failed: %s%s%s", id,
1932: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 1933: if (msg != NULL)
1934: xfree(msg);
1935: if (lang != NULL)
1936: xfree(lang);
1.44 markus 1937: }
1.152 markus 1938: packet_check_eom();
1.25 markus 1939: /* Free the channel. This will also close the socket. */
1.113 markus 1940: channel_free(c);
1.1 deraadt 1941: }
1942:
1.44 markus 1943: void
1.154 markus 1944: channel_input_channel_request(int type, u_int32_t seq, void *ctxt)
1.44 markus 1945: {
1946: int id;
1947: Channel *c;
1948:
1949: id = packet_get_int();
1950: c = channel_lookup(id);
1951:
1952: if (c == NULL ||
1953: (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1954: packet_disconnect("Received request for "
1955: "non-open channel %d.", id);
1956: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1957: debug2("callback start");
1.44 markus 1958: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1959: debug2("callback done");
1.44 markus 1960: } else {
1961: char *service = packet_get_string(NULL);
1.94 markus 1962: debug("channel %d: rcvd request for %s", c->self, service);
1.70 markus 1963: debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
1.44 markus 1964: xfree(service);
1965: }
1966: }
1967:
1.121 markus 1968: void
1.154 markus 1969: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 1970: {
1971: Channel *c;
1972: int id, adjust;
1973:
1974: if (!compat20)
1975: return;
1976:
1977: /* Get the channel number and verify it. */
1978: id = packet_get_int();
1979: c = channel_lookup(id);
1.1 deraadt 1980:
1.121 markus 1981: if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
1982: log("Received window adjust for "
1983: "non-open channel %d.", id);
1984: return;
1985: }
1986: adjust = packet_get_int();
1.152 markus 1987: packet_check_eom();
1.121 markus 1988: debug2("channel %d: rcvd adjust %d", id, adjust);
1989: c->remote_window += adjust;
1990: }
1.1 deraadt 1991:
1.121 markus 1992: void
1.154 markus 1993: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1994: {
1.121 markus 1995: Channel *c = NULL;
1996: u_short host_port;
1997: char *host, *originator_string;
1998: int remote_id, sock = -1;
1999:
2000: remote_id = packet_get_int();
2001: host = packet_get_string(NULL);
2002: host_port = packet_get_int();
1.25 markus 2003:
1.121 markus 2004: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2005: originator_string = packet_get_string(NULL);
2006: } else {
2007: originator_string = xstrdup("unknown (remote did not supply name)");
2008: }
1.152 markus 2009: packet_check_eom();
1.121 markus 2010: sock = channel_connect_to(host, host_port);
2011: if (sock != -1) {
2012: c = channel_new("connected socket",
2013: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2014: originator_string, 1);
2015: if (c == NULL) {
2016: error("channel_input_port_open: channel_new failed");
2017: close(sock);
2018: } else {
2019: c->remote_id = remote_id;
1.25 markus 2020: }
2021: }
1.121 markus 2022: if (c == NULL) {
2023: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2024: packet_put_int(remote_id);
2025: packet_send();
2026: }
2027: xfree(host);
1.1 deraadt 2028: }
2029:
1.121 markus 2030:
2031: /* -- tcp forwarding */
1.135 markus 2032:
2033: void
2034: channel_set_af(int af)
2035: {
2036: IPv4or6 = af;
2037: }
1.121 markus 2038:
1.160 markus 2039: static int
2040: channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port,
2041: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2042: {
1.113 markus 2043: Channel *c;
1.160 markus 2044: int success, sock, on = 1;
1.35 markus 2045: struct addrinfo hints, *ai, *aitop;
1.160 markus 2046: const char *host;
1.35 markus 2047: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.28 markus 2048: struct linger linger;
1.25 markus 2049:
1.87 markus 2050: success = 0;
1.160 markus 2051: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2052: listen_addr : host_to_connect;
1.87 markus 2053:
1.160 markus 2054: if (host == NULL) {
2055: error("No forward host name.");
2056: return success;
1.73 markus 2057: }
1.113 markus 2058: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2059: error("Forward host name too long.");
2060: return success;
2061: }
1.25 markus 2062:
1.28 markus 2063: /*
1.35 markus 2064: * getaddrinfo returns a loopback address if the hostname is
2065: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2066: */
1.35 markus 2067: memset(&hints, 0, sizeof(hints));
2068: hints.ai_family = IPv4or6;
2069: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2070: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2071: snprintf(strport, sizeof strport, "%d", listen_port);
1.35 markus 2072: if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2073: packet_disconnect("getaddrinfo: fatal error");
2074:
2075: for (ai = aitop; ai; ai = ai->ai_next) {
2076: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2077: continue;
2078: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2079: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2080: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2081: continue;
2082: }
2083: /* Create a port to listen for the host. */
2084: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2085: if (sock < 0) {
2086: /* this is no error since kernel may not support ipv6 */
2087: verbose("socket: %.100s", strerror(errno));
2088: continue;
2089: }
2090: /*
2091: * Set socket options. We would like the socket to disappear
2092: * as soon as it has been closed for whatever reason.
2093: */
2094: setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
2095: linger.l_onoff = 1;
2096: linger.l_linger = 5;
2097: setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
2098: debug("Local forwarding listening on %s port %s.", ntop, strport);
2099:
2100: /* Bind the socket to the address. */
2101: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2102: /* address can be in use ipv6 address is already bound */
2103: verbose("bind: %.100s", strerror(errno));
2104: close(sock);
2105: continue;
2106: }
2107: /* Start listening for connections on the socket. */
2108: if (listen(sock, 5) < 0) {
2109: error("listen: %.100s", strerror(errno));
2110: close(sock);
2111: continue;
2112: }
2113: /* Allocate a channel number for the socket. */
1.121 markus 2114: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2115: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.71 markus 2116: 0, xstrdup("port listener"), 1);
1.113 markus 2117: if (c == NULL) {
1.160 markus 2118: error("channel_setup_fwd_listener: channel_new failed");
1.113 markus 2119: close(sock);
2120: continue;
2121: }
2122: strlcpy(c->path, host, sizeof(c->path));
2123: c->host_port = port_to_connect;
2124: c->listening_port = listen_port;
1.35 markus 2125: success = 1;
2126: }
2127: if (success == 0)
1.160 markus 2128: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2129: listen_port);
1.35 markus 2130: freeaddrinfo(aitop);
1.87 markus 2131: return success;
1.25 markus 2132: }
1.1 deraadt 2133:
1.160 markus 2134: /* protocol local port fwd, used by ssh (and sshd in v1) */
2135: int
2136: channel_setup_local_fwd_listener(u_short listen_port,
2137: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2138: {
2139: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
2140: NULL, listen_port, host_to_connect, port_to_connect, gateway_ports);
2141: }
2142:
2143: /* protocol v2 remote port fwd, used by sshd */
2144: int
2145: channel_setup_remote_fwd_listener(const char *listen_address,
2146: u_short listen_port, int gateway_ports)
2147: {
2148: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
2149: listen_address, listen_port, NULL, 0, gateway_ports);
2150: }
2151:
1.27 markus 2152: /*
2153: * Initiate forwarding of connections to port "port" on remote host through
2154: * the secure channel to host:port from local side.
2155: */
1.1 deraadt 2156:
1.49 markus 2157: void
1.73 markus 2158: channel_request_remote_forwarding(u_short listen_port,
2159: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2160: {
1.153 markus 2161: int type, success = 0;
1.73 markus 2162:
1.25 markus 2163: /* Record locally that connection to this host/port is permitted. */
2164: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2165: fatal("channel_request_remote_forwarding: too many forwards");
2166:
2167: /* Send the forward request to the remote side. */
1.44 markus 2168: if (compat20) {
2169: const char *address_to_bind = "0.0.0.0";
2170: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2171: packet_put_cstring("tcpip-forward");
2172: packet_put_char(0); /* boolean: want reply */
2173: packet_put_cstring(address_to_bind);
2174: packet_put_int(listen_port);
1.73 markus 2175: packet_send();
2176: packet_write_wait();
2177: /* Assume that server accepts the request */
2178: success = 1;
1.44 markus 2179: } else {
2180: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2181: packet_put_int(listen_port);
2182: packet_put_cstring(host_to_connect);
1.44 markus 2183: packet_put_int(port_to_connect);
2184: packet_send();
2185: packet_write_wait();
1.73 markus 2186:
2187: /* Wait for response from the remote side. */
1.153 markus 2188: type = packet_read();
1.73 markus 2189: switch (type) {
2190: case SSH_SMSG_SUCCESS:
2191: success = 1;
2192: break;
2193: case SSH_SMSG_FAILURE:
2194: log("Warning: Server denied remote port forwarding.");
2195: break;
2196: default:
2197: /* Unknown packet */
2198: packet_disconnect("Protocol error for port forward request:"
2199: "received packet type %d.", type);
2200: }
2201: }
2202: if (success) {
2203: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2204: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2205: permitted_opens[num_permitted_opens].listen_port = listen_port;
2206: num_permitted_opens++;
1.44 markus 2207: }
1.1 deraadt 2208: }
2209:
1.27 markus 2210: /*
2211: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2212: * listening for the port, and sends back a success reply (or disconnect
2213: * message if there was an error). This never returns if there was an error.
2214: */
1.1 deraadt 2215:
1.49 markus 2216: void
1.56 markus 2217: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2218: {
1.31 markus 2219: u_short port, host_port;
1.25 markus 2220: char *hostname;
1.1 deraadt 2221:
1.25 markus 2222: /* Get arguments from the packet. */
2223: port = packet_get_int();
2224: hostname = packet_get_string(NULL);
2225: host_port = packet_get_int();
2226:
1.27 markus 2227: /*
2228: * Check that an unprivileged user is not trying to forward a
2229: * privileged port.
2230: */
1.25 markus 2231: if (port < IPPORT_RESERVED && !is_root)
2232: packet_disconnect("Requested forwarding of port %d but user is not root.",
2233: port);
1.73 markus 2234: /* Initiate forwarding */
1.160 markus 2235: channel_setup_local_fwd_listener(port, hostname, host_port, gateway_ports);
1.25 markus 2236:
2237: /* Free the argument string. */
2238: xfree(hostname);
1.1 deraadt 2239: }
2240:
1.99 markus 2241: /*
2242: * Permits opening to any host/port if permitted_opens[] is empty. This is
2243: * usually called by the server, because the user could connect to any port
2244: * anyway, and the server has no way to know but to trust the client anyway.
2245: */
2246: void
1.142 itojun 2247: channel_permit_all_opens(void)
1.99 markus 2248: {
2249: if (num_permitted_opens == 0)
2250: all_opens_permitted = 1;
2251: }
2252:
1.101 markus 2253: void
1.99 markus 2254: channel_add_permitted_opens(char *host, int port)
2255: {
2256: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2257: fatal("channel_request_remote_forwarding: too many forwards");
2258: debug("allow port forwarding to host %s port %d", host, port);
2259:
2260: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2261: permitted_opens[num_permitted_opens].port_to_connect = port;
2262: num_permitted_opens++;
2263:
2264: all_opens_permitted = 0;
2265: }
2266:
1.101 markus 2267: void
1.99 markus 2268: channel_clear_permitted_opens(void)
2269: {
2270: int i;
2271:
2272: for (i = 0; i < num_permitted_opens; i++)
2273: xfree(permitted_opens[i].host_to_connect);
2274: num_permitted_opens = 0;
2275:
2276: }
2277:
2278:
2279: /* return socket to remote host, port */
1.127 itojun 2280: static int
1.99 markus 2281: connect_to(const char *host, u_short port)
1.41 markus 2282: {
2283: struct addrinfo hints, *ai, *aitop;
2284: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2285: int gaierr;
2286: int sock = -1;
2287:
2288: memset(&hints, 0, sizeof(hints));
2289: hints.ai_family = IPv4or6;
2290: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2291: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2292: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2293: error("connect_to %.100s: unknown host (%s)", host,
2294: gai_strerror(gaierr));
1.41 markus 2295: return -1;
2296: }
2297: for (ai = aitop; ai; ai = ai->ai_next) {
2298: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2299: continue;
2300: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2301: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2302: error("connect_to: getnameinfo failed");
1.41 markus 2303: continue;
2304: }
2305: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2306: if (sock < 0) {
2307: error("socket: %.100s", strerror(errno));
2308: continue;
2309: }
1.80 markus 2310: if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
1.75 markus 2311: fatal("connect_to: F_SETFL: %s", strerror(errno));
2312: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2313: errno != EINPROGRESS) {
1.99 markus 2314: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2315: strerror(errno));
2316: close(sock);
1.89 stevesk 2317: continue; /* fail -- try next */
1.41 markus 2318: }
2319: break; /* success */
2320:
2321: }
2322: freeaddrinfo(aitop);
2323: if (!ai) {
1.99 markus 2324: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2325: return -1;
2326: }
2327: /* success */
2328: return sock;
2329: }
1.99 markus 2330:
1.73 markus 2331: int
1.130 stevesk 2332: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2333: {
2334: int i;
1.99 markus 2335:
1.73 markus 2336: for (i = 0; i < num_permitted_opens; i++)
2337: if (permitted_opens[i].listen_port == listen_port)
1.99 markus 2338: return connect_to(
1.73 markus 2339: permitted_opens[i].host_to_connect,
2340: permitted_opens[i].port_to_connect);
1.74 markus 2341: error("WARNING: Server requests forwarding for unknown listen_port %d",
2342: listen_port);
1.73 markus 2343: return -1;
2344: }
2345:
1.99 markus 2346: /* Check if connecting to that port is permitted and connect. */
2347: int
2348: channel_connect_to(const char *host, u_short port)
2349: {
2350: int i, permit;
2351:
2352: permit = all_opens_permitted;
2353: if (!permit) {
2354: for (i = 0; i < num_permitted_opens; i++)
2355: if (permitted_opens[i].port_to_connect == port &&
2356: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2357: permit = 1;
2358:
2359: }
2360: if (!permit) {
2361: log("Received request to connect to host %.100s port %d, "
2362: "but the request was denied.", host, port);
2363: return -1;
2364: }
2365: return connect_to(host, port);
2366: }
2367:
1.121 markus 2368: /* -- X11 forwarding */
1.1 deraadt 2369:
1.27 markus 2370: /*
2371: * Creates an internet domain socket for listening for X11 connections.
1.141 stevesk 2372: * Returns a suitable display number for the DISPLAY variable, or -1 if
2373: * an error occurs.
1.27 markus 2374: */
1.141 stevesk 2375: int
1.163 ! stevesk 2376: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.149 markus 2377: int single_connection)
1.1 deraadt 2378: {
1.149 markus 2379: Channel *nc = NULL;
1.31 markus 2380: int display_number, sock;
2381: u_short port;
1.35 markus 2382: struct addrinfo hints, *ai, *aitop;
2383: char strport[NI_MAXSERV];
2384: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 2385:
1.33 markus 2386: for (display_number = x11_display_offset;
1.148 deraadt 2387: display_number < MAX_DISPLAYS;
2388: display_number++) {
1.25 markus 2389: port = 6000 + display_number;
1.35 markus 2390: memset(&hints, 0, sizeof(hints));
2391: hints.ai_family = IPv4or6;
1.163 ! stevesk 2392: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 2393: hints.ai_socktype = SOCK_STREAM;
2394: snprintf(strport, sizeof strport, "%d", port);
2395: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2396: error("getaddrinfo: %.100s", gai_strerror(gaierr));
1.141 stevesk 2397: return -1;
1.25 markus 2398: }
1.35 markus 2399: for (ai = aitop; ai; ai = ai->ai_next) {
2400: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2401: continue;
2402: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2403: if (sock < 0) {
2404: error("socket: %.100s", strerror(errno));
1.141 stevesk 2405: return -1;
1.35 markus 2406: }
2407: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2408: debug("bind port %d: %.100s", port, strerror(errno));
2409: close(sock);
2410: for (n = 0; n < num_socks; n++) {
2411: close(socks[n]);
2412: }
2413: num_socks = 0;
2414: break;
2415: }
2416: socks[num_socks++] = sock;
2417: if (num_socks == NUM_SOCKS)
2418: break;
1.25 markus 2419: }
1.83 stevesk 2420: freeaddrinfo(aitop);
1.35 markus 2421: if (num_socks > 0)
2422: break;
1.25 markus 2423: }
2424: if (display_number >= MAX_DISPLAYS) {
2425: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 2426: return -1;
1.25 markus 2427: }
2428: /* Start listening for connections on the socket. */
1.35 markus 2429: for (n = 0; n < num_socks; n++) {
2430: sock = socks[n];
2431: if (listen(sock, 5) < 0) {
2432: error("listen: %.100s", strerror(errno));
2433: close(sock);
1.141 stevesk 2434: return -1;
1.35 markus 2435: }
1.25 markus 2436: }
1.35 markus 2437:
2438: /* Allocate a channel for each socket. */
2439: for (n = 0; n < num_socks; n++) {
2440: sock = socks[n];
1.149 markus 2441: nc = channel_new("x11 listener",
1.51 markus 2442: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2443: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.71 markus 2444: 0, xstrdup("X11 inet listener"), 1);
1.149 markus 2445: if (nc != NULL)
2446: nc->single_connection = single_connection;
1.35 markus 2447: }
1.1 deraadt 2448:
1.141 stevesk 2449: /* Return the display number for the DISPLAY environment variable. */
2450: return display_number;
1.1 deraadt 2451: }
2452:
1.127 itojun 2453: static int
1.77 markus 2454: connect_local_xsocket(u_int dnr)
1.1 deraadt 2455: {
1.25 markus 2456: int sock;
2457: struct sockaddr_un addr;
2458:
1.147 stevesk 2459: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2460: if (sock < 0)
2461: error("socket: %.100s", strerror(errno));
2462: memset(&addr, 0, sizeof(addr));
2463: addr.sun_family = AF_UNIX;
2464: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
2465: if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2466: return sock;
2467: close(sock);
1.25 markus 2468: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2469: return -1;
1.1 deraadt 2470: }
2471:
1.51 markus 2472: int
2473: x11_connect_display(void)
1.1 deraadt 2474: {
1.162 stevesk 2475: int display_number, sock = 0;
1.25 markus 2476: const char *display;
1.51 markus 2477: char buf[1024], *cp;
1.35 markus 2478: struct addrinfo hints, *ai, *aitop;
2479: char strport[NI_MAXSERV];
2480: int gaierr;
1.25 markus 2481:
2482: /* Try to open a socket for the local X server. */
2483: display = getenv("DISPLAY");
2484: if (!display) {
2485: error("DISPLAY not set.");
1.51 markus 2486: return -1;
1.25 markus 2487: }
1.27 markus 2488: /*
2489: * Now we decode the value of the DISPLAY variable and make a
2490: * connection to the real X server.
2491: */
2492:
2493: /*
2494: * Check if it is a unix domain socket. Unix domain displays are in
2495: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2496: */
1.25 markus 2497: if (strncmp(display, "unix:", 5) == 0 ||
2498: display[0] == ':') {
2499: /* Connect to the unix domain socket. */
2500: if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2501: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2502: display);
1.51 markus 2503: return -1;
1.25 markus 2504: }
2505: /* Create a socket. */
2506: sock = connect_local_xsocket(display_number);
2507: if (sock < 0)
1.51 markus 2508: return -1;
1.25 markus 2509:
2510: /* OK, we now have a connection to the display. */
1.51 markus 2511: return sock;
1.25 markus 2512: }
1.27 markus 2513: /*
2514: * Connect to an inet socket. The DISPLAY value is supposedly
2515: * hostname:d[.s], where hostname may also be numeric IP address.
2516: */
1.145 stevesk 2517: strlcpy(buf, display, sizeof(buf));
1.25 markus 2518: cp = strchr(buf, ':');
2519: if (!cp) {
2520: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 2521: return -1;
1.25 markus 2522: }
2523: *cp = 0;
1.27 markus 2524: /* buf now contains the host name. But first we parse the display number. */
1.25 markus 2525: if (sscanf(cp + 1, "%d", &display_number) != 1) {
2526: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2527: display);
1.51 markus 2528: return -1;
1.25 markus 2529: }
1.35 markus 2530:
2531: /* Look up the host address */
2532: memset(&hints, 0, sizeof(hints));
2533: hints.ai_family = IPv4or6;
2534: hints.ai_socktype = SOCK_STREAM;
2535: snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2536: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2537: error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
1.51 markus 2538: return -1;
1.25 markus 2539: }
1.35 markus 2540: for (ai = aitop; ai; ai = ai->ai_next) {
2541: /* Create a socket. */
2542: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2543: if (sock < 0) {
2544: debug("socket: %.100s", strerror(errno));
1.41 markus 2545: continue;
2546: }
2547: /* Connect it to the display. */
2548: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2549: debug("connect %.100s port %d: %.100s", buf,
2550: 6000 + display_number, strerror(errno));
2551: close(sock);
2552: continue;
2553: }
2554: /* Success */
2555: break;
1.35 markus 2556: }
2557: freeaddrinfo(aitop);
2558: if (!ai) {
1.49 markus 2559: error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
1.35 markus 2560: strerror(errno));
1.51 markus 2561: return -1;
1.25 markus 2562: }
1.162 stevesk 2563: set_nodelay(sock);
1.51 markus 2564: return sock;
2565: }
2566:
2567: /*
2568: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2569: * the remote channel number. We should do whatever we want, and respond
2570: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2571: */
2572:
2573: void
1.154 markus 2574: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 2575: {
1.113 markus 2576: Channel *c = NULL;
2577: int remote_id, sock = 0;
1.51 markus 2578: char *remote_host;
1.25 markus 2579:
1.113 markus 2580: debug("Received X11 open request.");
1.51 markus 2581:
1.113 markus 2582: remote_id = packet_get_int();
1.121 markus 2583:
2584: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 2585: remote_host = packet_get_string(NULL);
1.51 markus 2586: } else {
2587: remote_host = xstrdup("unknown (remote did not supply name)");
2588: }
1.152 markus 2589: packet_check_eom();
1.25 markus 2590:
1.51 markus 2591: /* Obtain a connection to the real X display. */
2592: sock = x11_connect_display();
1.113 markus 2593: if (sock != -1) {
2594: /* Allocate a channel for this connection. */
2595: c = channel_new("connected x11 socket",
2596: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2597: remote_host, 1);
2598: if (c == NULL) {
2599: error("x11_input_open: channel_new failed");
2600: close(sock);
2601: } else {
2602: c->remote_id = remote_id;
1.133 markus 2603: c->force_drain = 1;
1.113 markus 2604: }
2605: }
2606: if (c == NULL) {
1.51 markus 2607: /* Send refusal to the remote host. */
2608: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2609: packet_put_int(remote_id);
1.51 markus 2610: } else {
2611: /* Send a confirmation to the remote host. */
2612: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 2613: packet_put_int(remote_id);
2614: packet_put_int(c->self);
1.51 markus 2615: }
1.113 markus 2616: packet_send();
1.72 markus 2617: }
2618:
2619: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2620: void
1.154 markus 2621: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 2622: {
2623: int rchan = packet_get_int();
1.143 deraadt 2624: switch (type) {
1.72 markus 2625: case SSH_SMSG_AGENT_OPEN:
2626: error("Warning: ssh server tried agent forwarding.");
2627: break;
2628: case SSH_SMSG_X11_OPEN:
2629: error("Warning: ssh server tried X11 forwarding.");
2630: break;
2631: default:
1.154 markus 2632: error("deny_input_open: type %d", type);
1.72 markus 2633: break;
2634: }
2635: error("Warning: this is probably a break in attempt by a malicious server.");
2636: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2637: packet_put_int(rchan);
2638: packet_send();
1.1 deraadt 2639: }
2640:
1.27 markus 2641: /*
2642: * Requests forwarding of X11 connections, generates fake authentication
2643: * data, and enables authentication spoofing.
1.121 markus 2644: * This should be called in the client only.
1.27 markus 2645: */
1.49 markus 2646: void
1.51 markus 2647: x11_request_forwarding_with_spoofing(int client_session_id,
2648: const char *proto, const char *data)
1.1 deraadt 2649: {
1.77 markus 2650: u_int data_len = (u_int) strlen(data) / 2;
1.90 markus 2651: u_int i, value, len;
1.25 markus 2652: char *new_data;
2653: int screen_number;
2654: const char *cp;
2655: u_int32_t rand = 0;
2656:
2657: cp = getenv("DISPLAY");
2658: if (cp)
2659: cp = strchr(cp, ':');
2660: if (cp)
2661: cp = strchr(cp, '.');
2662: if (cp)
2663: screen_number = atoi(cp + 1);
2664: else
2665: screen_number = 0;
2666:
2667: /* Save protocol name. */
2668: x11_saved_proto = xstrdup(proto);
2669:
1.27 markus 2670: /*
2671: * Extract real authentication data and generate fake data of the
2672: * same length.
2673: */
1.25 markus 2674: x11_saved_data = xmalloc(data_len);
2675: x11_fake_data = xmalloc(data_len);
2676: for (i = 0; i < data_len; i++) {
2677: if (sscanf(data + 2 * i, "%2x", &value) != 1)
2678: fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2679: if (i % 4 == 0)
2680: rand = arc4random();
2681: x11_saved_data[i] = value;
2682: x11_fake_data[i] = rand & 0xff;
2683: rand >>= 8;
2684: }
2685: x11_saved_data_len = data_len;
2686: x11_fake_data_len = data_len;
2687:
2688: /* Convert the fake data into hex. */
1.90 markus 2689: len = 2 * data_len + 1;
2690: new_data = xmalloc(len);
1.25 markus 2691: for (i = 0; i < data_len; i++)
1.90 markus 2692: snprintf(new_data + 2 * i, len - 2 * i,
2693: "%02x", (u_char) x11_fake_data[i]);
1.25 markus 2694:
2695: /* Send the request packet. */
1.51 markus 2696: if (compat20) {
2697: channel_request_start(client_session_id, "x11-req", 0);
2698: packet_put_char(0); /* XXX bool single connection */
2699: } else {
2700: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2701: }
2702: packet_put_cstring(proto);
2703: packet_put_cstring(new_data);
1.25 markus 2704: packet_put_int(screen_number);
2705: packet_send();
2706: packet_write_wait();
2707: xfree(new_data);
1.1 deraadt 2708: }
2709:
1.121 markus 2710:
2711: /* -- agent forwarding */
2712:
1.1 deraadt 2713: /* Sends a message to the server to request authentication fd forwarding. */
2714:
1.49 markus 2715: void
1.142 itojun 2716: auth_request_forwarding(void)
1.1 deraadt 2717: {
1.25 markus 2718: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2719: packet_send();
2720: packet_write_wait();
1.1 deraadt 2721: }
2722:
1.27 markus 2723: /*
2724: * Returns the name of the forwarded authentication socket. Returns NULL if
2725: * there is no forwarded authentication socket. The returned value points to
2726: * a static buffer.
2727: */
1.1 deraadt 2728:
1.25 markus 2729: char *
1.142 itojun 2730: auth_get_socket_name(void)
1.1 deraadt 2731: {
1.121 markus 2732: return auth_sock_name;
1.1 deraadt 2733: }
2734:
1.12 markus 2735: /* removes the agent forwarding socket */
2736:
1.49 markus 2737: void
1.123 markus 2738: auth_sock_cleanup_proc(void *_pw)
1.25 markus 2739: {
1.123 markus 2740: struct passwd *pw = _pw;
2741:
1.122 markus 2742: if (auth_sock_name) {
1.123 markus 2743: temporarily_use_uid(pw);
1.122 markus 2744: unlink(auth_sock_name);
2745: rmdir(auth_sock_dir);
2746: auth_sock_name = NULL;
1.123 markus 2747: restore_uid();
1.122 markus 2748: }
1.12 markus 2749: }
2750:
1.27 markus 2751: /*
1.59 markus 2752: * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
1.27 markus 2753: * This starts forwarding authentication requests.
2754: */
1.1 deraadt 2755:
1.59 markus 2756: int
1.25 markus 2757: auth_input_request_forwarding(struct passwd * pw)
1.1 deraadt 2758: {
1.113 markus 2759: Channel *nc;
2760: int sock;
1.25 markus 2761: struct sockaddr_un sunaddr;
2762:
1.121 markus 2763: if (auth_get_socket_name() != NULL) {
2764: error("authentication forwarding requested twice.");
2765: return 0;
2766: }
1.25 markus 2767:
2768: /* Temporarily drop privileged uid for mkdir/bind. */
1.102 markus 2769: temporarily_use_uid(pw);
1.25 markus 2770:
2771: /* Allocate a buffer for the socket name, and format the name. */
1.121 markus 2772: auth_sock_name = xmalloc(MAXPATHLEN);
2773: auth_sock_dir = xmalloc(MAXPATHLEN);
2774: strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1.25 markus 2775:
2776: /* Create private directory for socket */
1.121 markus 2777: if (mkdtemp(auth_sock_dir) == NULL) {
2778: packet_send_debug("Agent forwarding disabled: "
2779: "mkdtemp() failed: %.100s", strerror(errno));
1.59 markus 2780: restore_uid();
1.121 markus 2781: xfree(auth_sock_name);
2782: xfree(auth_sock_dir);
2783: auth_sock_name = NULL;
2784: auth_sock_dir = NULL;
1.59 markus 2785: return 0;
2786: }
1.121 markus 2787: snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d",
2788: auth_sock_dir, (int) getpid());
1.25 markus 2789:
1.122 markus 2790: /* delete agent socket on fatal() */
1.123 markus 2791: fatal_add_cleanup(auth_sock_cleanup_proc, pw);
1.122 markus 2792:
1.25 markus 2793: /* Create the socket. */
2794: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2795: if (sock < 0)
2796: packet_disconnect("socket: %.100s", strerror(errno));
2797:
2798: /* Bind it to the name. */
2799: memset(&sunaddr, 0, sizeof(sunaddr));
2800: sunaddr.sun_family = AF_UNIX;
1.145 stevesk 2801: strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
1.25 markus 2802:
2803: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2804: packet_disconnect("bind: %.100s", strerror(errno));
2805:
2806: /* Restore the privileged uid. */
2807: restore_uid();
2808:
2809: /* Start listening on the socket. */
2810: if (listen(sock, 5) < 0)
2811: packet_disconnect("listen: %.100s", strerror(errno));
2812:
2813: /* Allocate a channel for the authentication agent socket. */
1.113 markus 2814: nc = channel_new("auth socket",
1.73 markus 2815: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2816: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2817: 0, xstrdup("auth socket"), 1);
1.113 markus 2818: if (nc == NULL) {
2819: error("auth_input_request_forwarding: channel_new failed");
1.123 markus 2820: auth_sock_cleanup_proc(pw);
1.124 markus 2821: fatal_remove_cleanup(auth_sock_cleanup_proc, pw);
1.113 markus 2822: close(sock);
2823: return 0;
2824: }
1.121 markus 2825: strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
1.59 markus 2826: return 1;
1.1 deraadt 2827: }
2828:
2829: /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2830:
1.49 markus 2831: void
1.154 markus 2832: auth_input_open_request(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2833: {
1.113 markus 2834: Channel *c = NULL;
2835: int remote_id, sock;
1.121 markus 2836: char *name;
1.41 markus 2837:
1.25 markus 2838: /* Read the remote channel number from the message. */
1.113 markus 2839: remote_id = packet_get_int();
1.152 markus 2840: packet_check_eom();
1.25 markus 2841:
1.27 markus 2842: /*
2843: * Get a connection to the local authentication agent (this may again
2844: * get forwarded).
2845: */
1.25 markus 2846: sock = ssh_get_authentication_socket();
2847:
1.27 markus 2848: /*
2849: * If we could not connect the agent, send an error message back to
2850: * the server. This should never happen unless the agent dies,
2851: * because authentication forwarding is only enabled if we have an
2852: * agent.
2853: */
1.113 markus 2854: if (sock >= 0) {
1.121 markus 2855: name = xstrdup("authentication agent connection");
2856: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2857: -1, 0, 0, 0, name, 1);
1.113 markus 2858: if (c == NULL) {
2859: error("auth_input_open_request: channel_new failed");
1.121 markus 2860: xfree(name);
1.113 markus 2861: close(sock);
2862: } else {
2863: c->remote_id = remote_id;
1.133 markus 2864: c->force_drain = 1;
1.113 markus 2865: }
2866: }
2867: if (c == NULL) {
1.25 markus 2868: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2869: packet_put_int(remote_id);
2870: } else {
2871: /* Send a confirmation to the remote host. */
2872: debug("Forwarding authentication connection.");
2873: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2874: packet_put_int(remote_id);
2875: packet_put_int(c->self);
1.25 markus 2876: }
2877: packet_send();
1.1 deraadt 2878: }