Annotation of src/usr.bin/ssh/channels.c, Revision 1.146
1.1 deraadt 1: /*
1.26 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
5: * This file contains functions for generic socket connection forwarding.
6: * There is also code for initiating connection forwarding for X11 connections,
7: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 8: *
1.67 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
14: *
1.44 markus 15: * SSH2 support added by Markus Friedl.
1.128 markus 16: * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
1.67 deraadt 17: * Copyright (c) 1999 Dug Song. All rights reserved.
18: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
19: *
20: * Redistribution and use in source and binary forms, with or without
21: * modification, are permitted provided that the following conditions
22: * are met:
23: * 1. Redistributions of source code must retain the above copyright
24: * notice, this list of conditions and the following disclaimer.
25: * 2. Redistributions in binary form must reproduce the above copyright
26: * notice, this list of conditions and the following disclaimer in the
27: * documentation and/or other materials provided with the distribution.
28: *
29: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
30: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
31: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
32: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
33: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
34: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
38: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 39: */
1.1 deraadt 40:
41: #include "includes.h"
1.146 ! stevesk 42: RCSID("$OpenBSD: channels.c,v 1.145 2001/12/06 18:09:23 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"
1.44 markus 57:
1.1 deraadt 58:
1.121 markus 59: /* -- channel core */
1.12 markus 60:
1.27 markus 61: /*
62: * Pointer to an array containing all allocated channels. The array is
63: * dynamically extended as needed.
64: */
1.113 markus 65: static Channel **channels = NULL;
1.1 deraadt 66:
1.27 markus 67: /*
68: * Size of the channel array. All slots of the array must always be
1.113 markus 69: * initialized (at least the type field); unused slots set to NULL
1.27 markus 70: */
1.1 deraadt 71: static int channels_alloc = 0;
72:
1.27 markus 73: /*
74: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 75: * updated in channel_new.
1.27 markus 76: */
1.84 markus 77: static int channel_max_fd = 0;
1.1 deraadt 78:
79:
1.121 markus 80: /* -- tcp forwarding */
1.1 deraadt 81:
1.27 markus 82: /*
83: * Data structure for storing which hosts are permitted for forward requests.
84: * The local sides of any remote forwards are stored in this array to prevent
85: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
86: * network (which might be behind a firewall).
87: */
1.25 markus 88: typedef struct {
1.41 markus 89: char *host_to_connect; /* Connect to 'host'. */
90: u_short port_to_connect; /* Connect to 'port'. */
91: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 92: } ForwardPermission;
93:
94: /* List of all permitted host/port pairs to connect. */
95: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 96:
1.1 deraadt 97: /* Number of permitted host/port pairs in the array. */
98: static int num_permitted_opens = 0;
1.27 markus 99: /*
100: * If this is true, all opens are permitted. This is the case on the server
101: * on which we have to trust the client anyway, and the user could do
102: * anything after logging in anyway.
103: */
1.1 deraadt 104: static int all_opens_permitted = 0;
105:
1.121 markus 106:
107: /* -- X11 forwarding */
108:
109: /* Maximum number of fake X11 displays to try. */
110: #define MAX_DISPLAYS 1000
111:
112: /* Saved X11 authentication protocol name. */
113: static char *x11_saved_proto = NULL;
114:
115: /* Saved X11 authentication data. This is the real data. */
116: static char *x11_saved_data = NULL;
117: static u_int x11_saved_data_len = 0;
118:
119: /*
120: * Fake X11 authentication data. This is what the server will be sending us;
121: * we should replace any occurrences of this by the real data.
122: */
123: static char *x11_fake_data = NULL;
124: static u_int x11_fake_data_len;
125:
126:
127: /* -- agent forwarding */
128:
129: #define NUM_SOCKS 10
130:
131: /* Name and directory of socket for authentication agent forwarding. */
132: static char *auth_sock_name = NULL;
133: static char *auth_sock_dir = NULL;
134:
1.82 markus 135: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 136: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 137:
1.121 markus 138: /* helper */
1.127 itojun 139: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 140:
1.121 markus 141: /* -- channel core */
1.41 markus 142:
143: Channel *
144: channel_lookup(int id)
145: {
146: Channel *c;
1.113 markus 147:
1.63 provos 148: if (id < 0 || id > channels_alloc) {
1.41 markus 149: log("channel_lookup: %d: bad id", id);
150: return NULL;
151: }
1.113 markus 152: c = channels[id];
153: if (c == NULL) {
1.41 markus 154: log("channel_lookup: %d: bad id: channel free", id);
155: return NULL;
156: }
157: return c;
1.55 markus 158: }
159:
1.27 markus 160: /*
1.55 markus 161: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 162: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 163: */
1.1 deraadt 164:
1.127 itojun 165: static void
1.71 markus 166: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
167: int extusage, int nonblock)
1.1 deraadt 168: {
1.25 markus 169: /* Update the maximum file descriptor value. */
1.84 markus 170: channel_max_fd = MAX(channel_max_fd, rfd);
171: channel_max_fd = MAX(channel_max_fd, wfd);
172: channel_max_fd = MAX(channel_max_fd, efd);
173:
1.27 markus 174: /* XXX set close-on-exec -markus */
1.55 markus 175:
1.52 markus 176: c->rfd = rfd;
177: c->wfd = wfd;
178: c->sock = (rfd == wfd) ? rfd : -1;
179: c->efd = efd;
180: c->extended_usage = extusage;
1.71 markus 181:
1.91 markus 182: /* XXX ugly hack: nonblock is only set by the server */
183: if (nonblock && isatty(c->rfd)) {
1.94 markus 184: debug("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 185: c->isatty = 1;
186: if (!isatty(c->wfd)) {
1.94 markus 187: error("channel %d: wfd %d is not a tty?",
1.91 markus 188: c->self, c->wfd);
189: }
190: } else {
191: c->isatty = 0;
192: }
193:
1.71 markus 194: /* enable nonblocking mode */
195: if (nonblock) {
196: if (rfd != -1)
197: set_nonblock(rfd);
198: if (wfd != -1)
199: set_nonblock(wfd);
200: if (efd != -1)
201: set_nonblock(efd);
202: }
1.52 markus 203: }
204:
205: /*
206: * Allocate a new channel object and set its type and socket. This will cause
207: * remote_name to be freed.
208: */
209:
1.113 markus 210: Channel *
1.52 markus 211: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.71 markus 212: int window, int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 213: {
214: int i, found;
215: Channel *c;
1.25 markus 216:
217: /* Do initial allocation if this is the first call. */
218: if (channels_alloc == 0) {
1.44 markus 219: chan_init();
1.25 markus 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);
1.25 markus 248: chan_init_iostates(c);
1.71 markus 249: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
1.25 markus 250: c->self = found;
251: c->type = type;
1.41 markus 252: c->ctype = ctype;
1.51 markus 253: c->local_window = window;
254: c->local_window_max = window;
255: c->local_consumed = 0;
256: c->local_maxpacket = maxpack;
1.25 markus 257: c->remote_id = -1;
258: c->remote_name = remote_name;
1.41 markus 259: c->remote_window = 0;
260: c->remote_maxpacket = 0;
261: c->cb_fn = NULL;
262: c->cb_arg = NULL;
263: c->cb_event = 0;
1.133 markus 264: c->force_drain = 0;
1.131 markus 265: c->detach_user = NULL;
1.65 markus 266: c->input_filter = NULL;
1.25 markus 267: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 268: return c;
1.1 deraadt 269: }
1.52 markus 270:
1.132 markus 271: static int
272: channel_find_maxfd(void)
273: {
274: int i, max = 0;
275: Channel *c;
276:
277: for (i = 0; i < channels_alloc; i++) {
278: c = channels[i];
279: if (c != NULL) {
280: max = MAX(max, c->rfd);
281: max = MAX(max, c->wfd);
282: max = MAX(max, c->efd);
283: }
284: }
285: return max;
286: }
287:
288: int
289: channel_close_fd(int *fdp)
290: {
291: int ret = 0, fd = *fdp;
292:
293: if (fd != -1) {
294: ret = close(fd);
295: *fdp = -1;
296: if (fd == channel_max_fd)
297: channel_max_fd = channel_find_maxfd();
298: }
299: return ret;
300: }
301:
1.52 markus 302: /* Close all channel fd/socket. */
303:
1.127 itojun 304: static void
1.52 markus 305: channel_close_fds(Channel *c)
306: {
1.118 markus 307: debug3("channel_close_fds: channel %d: r %d w %d e %d",
308: c->self, c->rfd, c->wfd, c->efd);
309:
1.132 markus 310: channel_close_fd(&c->sock);
311: channel_close_fd(&c->rfd);
312: channel_close_fd(&c->wfd);
313: channel_close_fd(&c->efd);
1.121 markus 314: }
315:
316: /* Free the channel and close its fd/socket. */
317:
318: void
319: channel_free(Channel *c)
320: {
321: char *s;
322: int i, n;
323:
324: for (n = 0, i = 0; i < channels_alloc; i++)
325: if (channels[i])
326: n++;
327: debug("channel_free: channel %d: %s, nchannels %d", c->self,
328: c->remote_name ? c->remote_name : "???", n);
329:
330: s = channel_open_message();
331: debug3("channel_free: status: %s", s);
332: xfree(s);
333:
334: if (c->sock != -1)
335: shutdown(c->sock, SHUT_RDWR);
336: channel_close_fds(c);
337: buffer_free(&c->input);
338: buffer_free(&c->output);
339: buffer_free(&c->extended);
340: if (c->remote_name) {
341: xfree(c->remote_name);
342: c->remote_name = NULL;
343: }
344: channels[c->self] = NULL;
345: xfree(c);
346: }
347:
348: void
1.126 markus 349: channel_free_all(void)
1.121 markus 350: {
351: int i;
352:
1.126 markus 353: for (i = 0; i < channels_alloc; i++)
354: if (channels[i] != NULL)
355: channel_free(channels[i]);
1.131 markus 356: }
357:
1.121 markus 358: /*
359: * Closes the sockets/fds of all channels. This is used to close extra file
360: * descriptors after a fork.
361: */
362:
363: void
1.142 itojun 364: channel_close_all(void)
1.121 markus 365: {
366: int i;
367:
368: for (i = 0; i < channels_alloc; i++)
369: if (channels[i] != NULL)
370: channel_close_fds(channels[i]);
371: }
372:
373: /*
1.131 markus 374: * Stop listening to channels.
375: */
376:
377: void
378: channel_stop_listening(void)
379: {
380: int i;
381: Channel *c;
382:
383: for (i = 0; i < channels_alloc; i++) {
384: c = channels[i];
385: if (c != NULL) {
386: switch (c->type) {
387: case SSH_CHANNEL_AUTH_SOCKET:
388: case SSH_CHANNEL_PORT_LISTENER:
389: case SSH_CHANNEL_RPORT_LISTENER:
390: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 391: channel_close_fd(&c->sock);
1.131 markus 392: channel_free(c);
393: break;
394: }
395: }
396: }
397: }
398:
399: /*
1.121 markus 400: * Returns true if no channel has too much buffered data, and false if one or
401: * more channel is overfull.
402: */
403:
404: int
1.142 itojun 405: channel_not_very_much_buffered_data(void)
1.121 markus 406: {
407: u_int i;
408: Channel *c;
409:
410: for (i = 0; i < channels_alloc; i++) {
411: c = channels[i];
412: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 413: #if 0
414: if (!compat20 &&
415: buffer_len(&c->input) > packet_get_maxsize()) {
1.121 markus 416: debug("channel %d: big input buffer %d",
417: c->self, buffer_len(&c->input));
418: return 0;
419: }
1.136 markus 420: #endif
1.121 markus 421: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.136 markus 422: debug("channel %d: big output buffer %d > %d",
423: c->self, buffer_len(&c->output),
424: packet_get_maxsize());
1.121 markus 425: return 0;
426: }
427: }
428: }
429: return 1;
430: }
431:
432: /* Returns true if any channel is still open. */
433:
434: int
1.142 itojun 435: channel_still_open(void)
1.121 markus 436: {
437: int i;
438: Channel *c;
439:
440: for (i = 0; i < channels_alloc; i++) {
441: c = channels[i];
442: if (c == NULL)
443: continue;
444: switch (c->type) {
445: case SSH_CHANNEL_X11_LISTENER:
446: case SSH_CHANNEL_PORT_LISTENER:
447: case SSH_CHANNEL_RPORT_LISTENER:
448: case SSH_CHANNEL_CLOSED:
449: case SSH_CHANNEL_AUTH_SOCKET:
450: case SSH_CHANNEL_DYNAMIC:
451: case SSH_CHANNEL_CONNECTING:
452: case SSH_CHANNEL_ZOMBIE:
453: continue;
454: case SSH_CHANNEL_LARVAL:
455: if (!compat20)
456: fatal("cannot happen: SSH_CHANNEL_LARVAL");
457: continue;
458: case SSH_CHANNEL_OPENING:
459: case SSH_CHANNEL_OPEN:
460: case SSH_CHANNEL_X11_OPEN:
461: return 1;
462: case SSH_CHANNEL_INPUT_DRAINING:
463: case SSH_CHANNEL_OUTPUT_DRAINING:
464: if (!compat13)
465: fatal("cannot happen: OUT_DRAIN");
466: return 1;
467: default:
468: fatal("channel_still_open: bad channel type %d", c->type);
469: /* NOTREACHED */
470: }
471: }
472: return 0;
473: }
474:
475: /* Returns the id of an open channel suitable for keepaliving */
476:
477: int
1.142 itojun 478: channel_find_open(void)
1.121 markus 479: {
480: int i;
481: Channel *c;
482:
483: for (i = 0; i < channels_alloc; i++) {
484: c = channels[i];
485: if (c == NULL)
486: continue;
487: switch (c->type) {
488: case SSH_CHANNEL_CLOSED:
489: case SSH_CHANNEL_DYNAMIC:
490: case SSH_CHANNEL_X11_LISTENER:
491: case SSH_CHANNEL_PORT_LISTENER:
492: case SSH_CHANNEL_RPORT_LISTENER:
493: case SSH_CHANNEL_OPENING:
494: case SSH_CHANNEL_CONNECTING:
495: case SSH_CHANNEL_ZOMBIE:
496: continue;
497: case SSH_CHANNEL_LARVAL:
498: case SSH_CHANNEL_AUTH_SOCKET:
499: case SSH_CHANNEL_OPEN:
500: case SSH_CHANNEL_X11_OPEN:
501: return i;
502: case SSH_CHANNEL_INPUT_DRAINING:
503: case SSH_CHANNEL_OUTPUT_DRAINING:
504: if (!compat13)
505: fatal("cannot happen: OUT_DRAIN");
506: return i;
507: default:
508: fatal("channel_find_open: bad channel type %d", c->type);
509: /* NOTREACHED */
510: }
511: }
512: return -1;
513: }
514:
515:
516: /*
517: * Returns a message describing the currently open forwarded connections,
518: * suitable for sending to the client. The message contains crlf pairs for
519: * newlines.
520: */
521:
522: char *
1.142 itojun 523: channel_open_message(void)
1.121 markus 524: {
525: Buffer buffer;
526: Channel *c;
527: char buf[1024], *cp;
528: int i;
529:
530: buffer_init(&buffer);
531: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
532: buffer_append(&buffer, buf, strlen(buf));
533: for (i = 0; i < channels_alloc; i++) {
534: c = channels[i];
535: if (c == NULL)
536: continue;
537: switch (c->type) {
538: case SSH_CHANNEL_X11_LISTENER:
539: case SSH_CHANNEL_PORT_LISTENER:
540: case SSH_CHANNEL_RPORT_LISTENER:
541: case SSH_CHANNEL_CLOSED:
542: case SSH_CHANNEL_AUTH_SOCKET:
543: case SSH_CHANNEL_ZOMBIE:
544: continue;
545: case SSH_CHANNEL_LARVAL:
546: case SSH_CHANNEL_OPENING:
547: case SSH_CHANNEL_CONNECTING:
548: case SSH_CHANNEL_DYNAMIC:
549: case SSH_CHANNEL_OPEN:
550: case SSH_CHANNEL_X11_OPEN:
551: case SSH_CHANNEL_INPUT_DRAINING:
552: case SSH_CHANNEL_OUTPUT_DRAINING:
553: snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
554: c->self, c->remote_name,
555: c->type, c->remote_id,
556: c->istate, buffer_len(&c->input),
557: c->ostate, buffer_len(&c->output),
558: c->rfd, c->wfd);
559: buffer_append(&buffer, buf, strlen(buf));
560: continue;
561: default:
562: fatal("channel_open_message: bad channel type %d", c->type);
563: /* NOTREACHED */
564: }
565: }
566: buffer_append(&buffer, "\0", 1);
567: cp = xstrdup(buffer_ptr(&buffer));
568: buffer_free(&buffer);
569: return cp;
570: }
571:
572: void
573: channel_send_open(int id)
574: {
575: Channel *c = channel_lookup(id);
576: if (c == NULL) {
577: log("channel_send_open: %d: bad id", id);
578: return;
579: }
580: debug("send channel open %d", id);
581: packet_start(SSH2_MSG_CHANNEL_OPEN);
582: packet_put_cstring(c->ctype);
583: packet_put_int(c->self);
584: packet_put_int(c->local_window);
585: packet_put_int(c->local_maxpacket);
586: packet_send();
587: }
588:
589: void
590: channel_request(int id, char *service, int wantconfirm)
591: {
592: channel_request_start(id, service, wantconfirm);
593: packet_send();
594: debug("channel request %d: %s", id, service) ;
595: }
596: void
597: channel_request_start(int id, char *service, int wantconfirm)
598: {
599: Channel *c = channel_lookup(id);
600: if (c == NULL) {
601: log("channel_request: %d: bad id", id);
602: return;
603: }
604: packet_start(SSH2_MSG_CHANNEL_REQUEST);
605: packet_put_int(c->remote_id);
606: packet_put_cstring(service);
607: packet_put_char(wantconfirm);
608: }
609: void
610: channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
611: {
612: Channel *c = channel_lookup(id);
613: if (c == NULL) {
614: log("channel_register_callback: %d: bad id", id);
615: return;
616: }
617: c->cb_event = mtype;
618: c->cb_fn = fn;
619: c->cb_arg = arg;
620: }
621: void
622: channel_register_cleanup(int id, channel_callback_fn *fn)
623: {
624: Channel *c = channel_lookup(id);
625: if (c == NULL) {
626: log("channel_register_cleanup: %d: bad id", id);
627: return;
628: }
1.131 markus 629: c->detach_user = fn;
1.121 markus 630: }
631: void
632: channel_cancel_cleanup(int id)
633: {
634: Channel *c = channel_lookup(id);
635: if (c == NULL) {
636: log("channel_cancel_cleanup: %d: bad id", id);
637: return;
1.52 markus 638: }
1.131 markus 639: c->detach_user = NULL;
1.121 markus 640: }
641: void
642: channel_register_filter(int id, channel_filter_fn *fn)
643: {
644: Channel *c = channel_lookup(id);
645: if (c == NULL) {
646: log("channel_register_filter: %d: bad id", id);
647: return;
1.52 markus 648: }
1.121 markus 649: c->input_filter = fn;
1.52 markus 650: }
651:
1.49 markus 652: void
1.121 markus 653: channel_set_fds(int id, int rfd, int wfd, int efd,
654: int extusage, int nonblock)
1.1 deraadt 655: {
1.121 markus 656: Channel *c = channel_lookup(id);
657: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
658: fatal("channel_activate for non-larval channel %d.", id);
659: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
660: c->type = SSH_CHANNEL_OPEN;
661: /* XXX window size? */
662: c->local_window = c->local_window_max = c->local_maxpacket * 2;
663: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
664: packet_put_int(c->remote_id);
665: packet_put_int(c->local_window);
666: packet_send();
1.1 deraadt 667: }
668:
1.27 markus 669: /*
1.41 markus 670: * 'channel_pre*' are called just before select() to add any bits relevant to
671: * channels in the select bitmasks.
672: */
673: /*
674: * 'channel_post*': perform any appropriate operations for channels which
675: * have events pending.
1.27 markus 676: */
1.41 markus 677: typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
678: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
679: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
680:
1.127 itojun 681: static void
1.41 markus 682: channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
683: {
684: FD_SET(c->sock, readset);
685: }
686:
1.127 itojun 687: static void
1.75 markus 688: channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
689: {
690: debug3("channel %d: waiting for connection", c->self);
691: FD_SET(c->sock, writeset);
692: }
693:
1.127 itojun 694: static void
1.41 markus 695: channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
696: {
697: if (buffer_len(&c->input) < packet_get_maxsize())
698: FD_SET(c->sock, readset);
699: if (buffer_len(&c->output) > 0)
700: FD_SET(c->sock, writeset);
701: }
1.1 deraadt 702:
1.127 itojun 703: static void
1.41 markus 704: channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
705: {
706: /* test whether sockets are 'alive' for read/write */
707: if (c->istate == CHAN_INPUT_OPEN)
708: if (buffer_len(&c->input) < packet_get_maxsize())
709: FD_SET(c->sock, readset);
710: if (c->ostate == CHAN_OUTPUT_OPEN ||
711: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
712: if (buffer_len(&c->output) > 0) {
713: FD_SET(c->sock, writeset);
714: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
715: chan_obuf_empty(c);
716: }
717: }
718: }
719:
1.127 itojun 720: static void
1.44 markus 721: channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset)
722: {
723: if (c->istate == CHAN_INPUT_OPEN &&
724: c->remote_window > 0 &&
725: buffer_len(&c->input) < c->remote_window)
726: FD_SET(c->rfd, readset);
727: if (c->ostate == CHAN_OUTPUT_OPEN ||
728: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
729: if (buffer_len(&c->output) > 0) {
730: FD_SET(c->wfd, writeset);
731: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
732: chan_obuf_empty(c);
733: }
734: }
735: /** XXX check close conditions, too */
736: if (c->efd != -1) {
737: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
738: buffer_len(&c->extended) > 0)
739: FD_SET(c->efd, writeset);
740: else if (c->extended_usage == CHAN_EXTENDED_READ &&
741: buffer_len(&c->extended) < c->remote_window)
742: FD_SET(c->efd, readset);
743: }
744: }
745:
1.127 itojun 746: static void
1.41 markus 747: channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
748: {
749: if (buffer_len(&c->input) == 0) {
750: packet_start(SSH_MSG_CHANNEL_CLOSE);
751: packet_put_int(c->remote_id);
752: packet_send();
753: c->type = SSH_CHANNEL_CLOSED;
1.105 markus 754: debug("channel %d: closing after input drain.", c->self);
1.41 markus 755: }
756: }
757:
1.127 itojun 758: static void
1.41 markus 759: channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
760: {
761: if (buffer_len(&c->output) == 0)
1.113 markus 762: chan_mark_dead(c);
1.49 markus 763: else
1.41 markus 764: FD_SET(c->sock, writeset);
765: }
766:
767: /*
768: * This is a special state for X11 authentication spoofing. An opened X11
769: * connection (when authentication spoofing is being done) remains in this
770: * state until the first packet has been completely read. The authentication
771: * data in that packet is then substituted by the real data if it matches the
772: * fake data, and the channel is put into normal mode.
1.51 markus 773: * XXX All this happens at the client side.
1.121 markus 774: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 775: */
1.127 itojun 776: static int
1.121 markus 777: x11_open_helper(Buffer *b)
1.1 deraadt 778: {
1.77 markus 779: u_char *ucp;
780: u_int proto_len, data_len;
1.25 markus 781:
1.41 markus 782: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 783: if (buffer_len(b) < 12)
1.41 markus 784: return 0;
785:
786: /* Parse the lengths of variable-length fields. */
1.121 markus 787: ucp = (u_char *) buffer_ptr(b);
1.41 markus 788: if (ucp[0] == 0x42) { /* Byte order MSB first. */
789: proto_len = 256 * ucp[6] + ucp[7];
790: data_len = 256 * ucp[8] + ucp[9];
791: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
792: proto_len = ucp[6] + 256 * ucp[7];
793: data_len = ucp[8] + 256 * ucp[9];
794: } else {
795: debug("Initial X11 packet contains bad byte order byte: 0x%x",
796: ucp[0]);
797: return -1;
798: }
799:
800: /* Check if the whole packet is in buffer. */
1.121 markus 801: if (buffer_len(b) <
1.41 markus 802: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
803: return 0;
804:
805: /* Check if authentication protocol matches. */
806: if (proto_len != strlen(x11_saved_proto) ||
807: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
808: debug("X11 connection uses different authentication protocol.");
809: return -1;
810: }
811: /* Check if authentication data matches our fake data. */
812: if (data_len != x11_fake_data_len ||
813: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
814: x11_fake_data, x11_fake_data_len) != 0) {
815: debug("X11 auth data does not match fake data.");
816: return -1;
817: }
818: /* Check fake data length */
819: if (x11_fake_data_len != x11_saved_data_len) {
820: error("X11 fake_data_len %d != saved_data_len %d",
821: x11_fake_data_len, x11_saved_data_len);
822: return -1;
823: }
824: /*
825: * Received authentication protocol and data match
826: * our fake data. Substitute the fake data with real
827: * data.
828: */
829: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
830: x11_saved_data, x11_saved_data_len);
831: return 1;
832: }
833:
1.127 itojun 834: static void
1.41 markus 835: channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
836: {
1.121 markus 837: int ret = x11_open_helper(&c->output);
1.41 markus 838: if (ret == 1) {
839: /* Start normal processing for the channel. */
840: c->type = SSH_CHANNEL_OPEN;
1.47 markus 841: channel_pre_open_13(c, readset, writeset);
1.41 markus 842: } else if (ret == -1) {
843: /*
844: * We have received an X11 connection that has bad
845: * authentication information.
846: */
1.98 millert 847: log("X11 connection rejected because of wrong authentication.");
1.41 markus 848: buffer_clear(&c->input);
849: buffer_clear(&c->output);
1.132 markus 850: channel_close_fd(&c->sock);
1.41 markus 851: c->sock = -1;
852: c->type = SSH_CHANNEL_CLOSED;
853: packet_start(SSH_MSG_CHANNEL_CLOSE);
854: packet_put_int(c->remote_id);
855: packet_send();
856: }
857: }
1.25 markus 858:
1.127 itojun 859: static void
1.51 markus 860: channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 861: {
1.121 markus 862: int ret = x11_open_helper(&c->output);
1.133 markus 863:
864: /* c->force_drain = 1; */
865:
1.41 markus 866: if (ret == 1) {
867: c->type = SSH_CHANNEL_OPEN;
1.57 markus 868: if (compat20)
869: channel_pre_open_20(c, readset, writeset);
870: else
871: channel_pre_open_15(c, readset, writeset);
1.41 markus 872: } else if (ret == -1) {
873: debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.51 markus 874: chan_read_failed(c); /** force close? */
1.41 markus 875: chan_write_failed(c);
876: debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
877: }
878: }
1.25 markus 879:
1.104 markus 880: /* try to decode a socks4 header */
1.127 itojun 881: static int
1.104 markus 882: channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
1.103 markus 883: {
884: u_char *p, *host;
1.109 markus 885: int len, have, i, found;
1.104 markus 886: char username[256];
1.103 markus 887: struct {
888: u_int8_t version;
889: u_int8_t command;
890: u_int16_t dest_port;
1.104 markus 891: struct in_addr dest_addr;
1.103 markus 892: } s4_req, s4_rsp;
893:
1.104 markus 894: debug2("channel %d: decode socks4", c->self);
1.109 markus 895:
896: have = buffer_len(&c->input);
897: len = sizeof(s4_req);
898: if (have < len)
899: return 0;
900: p = buffer_ptr(&c->input);
901: for (found = 0, i = len; i < have; i++) {
902: if (p[i] == '\0') {
903: found = 1;
904: break;
905: }
906: if (i > 1024) {
907: /* the peer is probably sending garbage */
908: debug("channel %d: decode socks4: too long",
909: c->self);
910: return -1;
911: }
912: }
913: if (!found)
914: return 0;
1.103 markus 915: buffer_get(&c->input, (char *)&s4_req.version, 1);
916: buffer_get(&c->input, (char *)&s4_req.command, 1);
917: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 918: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 919: have = buffer_len(&c->input);
1.103 markus 920: p = buffer_ptr(&c->input);
921: len = strlen(p);
1.106 markus 922: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 923: if (len > have)
1.104 markus 924: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 925: c->self, len, have);
926: strlcpy(username, p, sizeof(username));
927: buffer_consume(&c->input, len);
928: buffer_consume(&c->input, 1); /* trailing '\0' */
929:
1.104 markus 930: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 931: strlcpy(c->path, host, sizeof(c->path));
932: c->host_port = ntohs(s4_req.dest_port);
933:
1.106 markus 934: debug("channel %d: dynamic request: socks4 host %s port %u command %u",
935: c->self, host, c->host_port, s4_req.command);
1.103 markus 936:
1.104 markus 937: if (s4_req.command != 1) {
938: debug("channel %d: cannot handle: socks4 cn %d",
939: c->self, s4_req.command);
940: return -1;
1.103 markus 941: }
1.104 markus 942: s4_rsp.version = 0; /* vn: 0 for reply */
943: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 944: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 945: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.103 markus 946: buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
1.104 markus 947: return 1;
948: }
949:
950: /* dynamic port forwarding */
1.127 itojun 951: static void
1.104 markus 952: channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
953: {
954: u_char *p;
955: int have, ret;
1.103 markus 956:
1.104 markus 957: have = buffer_len(&c->input);
1.137 markus 958: c->delayed = 0;
1.104 markus 959: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 960: /* buffer_dump(&c->input); */
1.104 markus 961: /* check if the fixed size part of the packet is in buffer. */
962: if (have < 4) {
963: /* need more */
964: FD_SET(c->sock, readset);
965: return;
966: }
967: /* try to guess the protocol */
968: p = buffer_ptr(&c->input);
969: switch (p[0]) {
970: case 0x04:
971: ret = channel_decode_socks4(c, readset, writeset);
972: break;
973: default:
974: ret = -1;
975: break;
976: }
977: if (ret < 0) {
1.113 markus 978: chan_mark_dead(c);
1.104 markus 979: } else if (ret == 0) {
980: debug2("channel %d: pre_dynamic: need more", c->self);
981: /* need more */
982: FD_SET(c->sock, readset);
983: } else {
984: /* switch to the next state */
985: c->type = SSH_CHANNEL_OPENING;
986: port_open_helper(c, "direct-tcpip");
987: }
1.103 markus 988: }
989:
1.41 markus 990: /* This is our fake X11 server socket. */
1.127 itojun 991: static void
1.41 markus 992: channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
993: {
1.113 markus 994: Channel *nc;
1.41 markus 995: struct sockaddr addr;
1.146 ! stevesk 996: int newsock, on = 1;
1.41 markus 997: socklen_t addrlen;
1.85 markus 998: char buf[16384], *remote_ipaddr;
1.51 markus 999: int remote_port;
1.25 markus 1000:
1.41 markus 1001: if (FD_ISSET(c->sock, readset)) {
1002: debug("X11 connection requested.");
1003: addrlen = sizeof(addr);
1004: newsock = accept(c->sock, &addr, &addrlen);
1005: if (newsock < 0) {
1006: error("accept: %.100s", strerror(errno));
1007: return;
1008: }
1.146 ! stevesk 1009: if (setsockopt(newsock, IPPROTO_TCP, TCP_NODELAY, &on,
! 1010: sizeof on) == -1)
! 1011: error("setsockopt TCP_NODELAY: %.100s",
! 1012: strerror(errno));
1.85 markus 1013: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1014: remote_port = get_peer_port(newsock);
1.41 markus 1015: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1016: remote_ipaddr, remote_port);
1.51 markus 1017:
1.113 markus 1018: nc = channel_new("accepted x11 socket",
1.51 markus 1019: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1020: c->local_window_max, c->local_maxpacket,
1.71 markus 1021: 0, xstrdup(buf), 1);
1.113 markus 1022: if (nc == NULL) {
1023: close(newsock);
1024: xfree(remote_ipaddr);
1025: return;
1026: }
1.51 markus 1027: if (compat20) {
1028: packet_start(SSH2_MSG_CHANNEL_OPEN);
1029: packet_put_cstring("x11");
1.113 markus 1030: packet_put_int(nc->self);
1.51 markus 1031: packet_put_int(c->local_window_max);
1032: packet_put_int(c->local_maxpacket);
1.85 markus 1033: /* originator ipaddr and port */
1034: packet_put_cstring(remote_ipaddr);
1.57 markus 1035: if (datafellows & SSH_BUG_X11FWD) {
1036: debug("ssh2 x11 bug compat mode");
1037: } else {
1038: packet_put_int(remote_port);
1039: }
1.51 markus 1040: packet_send();
1041: } else {
1042: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1043: packet_put_int(nc->self);
1.121 markus 1044: if (packet_get_protocol_flags() &
1045: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1046: packet_put_cstring(buf);
1.51 markus 1047: packet_send();
1048: }
1.85 markus 1049: xfree(remote_ipaddr);
1.41 markus 1050: }
1051: }
1.25 markus 1052:
1.127 itojun 1053: static void
1.103 markus 1054: port_open_helper(Channel *c, char *rtype)
1055: {
1056: int direct;
1057: char buf[1024];
1058: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1059: u_short remote_port = get_peer_port(c->sock);
1060:
1061: direct = (strcmp(rtype, "direct-tcpip") == 0);
1062:
1063: snprintf(buf, sizeof buf,
1064: "%s: listening port %d for %.100s port %d, "
1065: "connect from %.200s port %d",
1066: rtype, c->listening_port, c->path, c->host_port,
1067: remote_ipaddr, remote_port);
1068:
1069: xfree(c->remote_name);
1070: c->remote_name = xstrdup(buf);
1071:
1072: if (compat20) {
1073: packet_start(SSH2_MSG_CHANNEL_OPEN);
1074: packet_put_cstring(rtype);
1075: packet_put_int(c->self);
1076: packet_put_int(c->local_window_max);
1077: packet_put_int(c->local_maxpacket);
1078: if (direct) {
1079: /* target host, port */
1080: packet_put_cstring(c->path);
1081: packet_put_int(c->host_port);
1082: } else {
1083: /* listen address, port */
1084: packet_put_cstring(c->path);
1085: packet_put_int(c->listening_port);
1086: }
1087: /* originator host and port */
1088: packet_put_cstring(remote_ipaddr);
1089: packet_put_int(remote_port);
1090: packet_send();
1091: } else {
1092: packet_start(SSH_MSG_PORT_OPEN);
1093: packet_put_int(c->self);
1094: packet_put_cstring(c->path);
1095: packet_put_int(c->host_port);
1.121 markus 1096: if (packet_get_protocol_flags() &
1097: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1098: packet_put_cstring(c->remote_name);
1099: packet_send();
1100: }
1101: xfree(remote_ipaddr);
1102: }
1103:
1.41 markus 1104: /*
1105: * This socket is listening for connections to a forwarded TCP/IP port.
1106: */
1.127 itojun 1107: static void
1.41 markus 1108: channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1109: {
1.103 markus 1110: Channel *nc;
1.41 markus 1111: struct sockaddr addr;
1.113 markus 1112: int newsock, nextstate;
1.41 markus 1113: socklen_t addrlen;
1.103 markus 1114: char *rtype;
1.73 markus 1115:
1.41 markus 1116: if (FD_ISSET(c->sock, readset)) {
1117: debug("Connection to port %d forwarding "
1118: "to %.100s port %d requested.",
1119: c->listening_port, c->path, c->host_port);
1.103 markus 1120:
1.137 markus 1121: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1122: nextstate = SSH_CHANNEL_OPENING;
1123: rtype = "forwarded-tcpip";
1124: } else {
1125: if (c->host_port == 0) {
1126: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1127: rtype = "dynamic-tcpip";
1.137 markus 1128: } else {
1129: nextstate = SSH_CHANNEL_OPENING;
1130: rtype = "direct-tcpip";
1131: }
1132: }
1.103 markus 1133:
1.41 markus 1134: addrlen = sizeof(addr);
1135: newsock = accept(c->sock, &addr, &addrlen);
1136: if (newsock < 0) {
1137: error("accept: %.100s", strerror(errno));
1138: return;
1139: }
1.113 markus 1140: nc = channel_new(rtype,
1.103 markus 1141: nextstate, newsock, newsock, -1,
1.41 markus 1142: c->local_window_max, c->local_maxpacket,
1.103 markus 1143: 0, xstrdup(rtype), 1);
1144: if (nc == NULL) {
1.113 markus 1145: error("channel_post_port_listener: no new channel:");
1146: close(newsock);
1.103 markus 1147: return;
1.41 markus 1148: }
1.103 markus 1149: nc->listening_port = c->listening_port;
1150: nc->host_port = c->host_port;
1151: strlcpy(nc->path, c->path, sizeof(nc->path));
1152:
1.137 markus 1153: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1154: /*
1155: * do not call the channel_post handler until
1156: * this flag has been reset by a pre-handler.
1157: * otherwise the FD_ISSET calls might overflow
1158: */
1159: nc->delayed = 1;
1160: } else {
1.103 markus 1161: port_open_helper(nc, rtype);
1.137 markus 1162: }
1.41 markus 1163: }
1164: }
1.25 markus 1165:
1.41 markus 1166: /*
1167: * This is the authentication agent socket listening for connections from
1168: * clients.
1169: */
1.127 itojun 1170: static void
1.41 markus 1171: channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1172: {
1.113 markus 1173: Channel *nc;
1.121 markus 1174: char *name;
1.113 markus 1175: int newsock;
1.41 markus 1176: struct sockaddr addr;
1177: socklen_t addrlen;
1.25 markus 1178:
1.41 markus 1179: if (FD_ISSET(c->sock, readset)) {
1180: addrlen = sizeof(addr);
1181: newsock = accept(c->sock, &addr, &addrlen);
1182: if (newsock < 0) {
1183: error("accept from auth socket: %.100s", strerror(errno));
1184: return;
1185: }
1.121 markus 1186: name = xstrdup("accepted auth socket");
1.113 markus 1187: nc = channel_new("accepted auth socket",
1.73 markus 1188: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1189: c->local_window_max, c->local_maxpacket,
1.121 markus 1190: 0, name, 1);
1.113 markus 1191: if (nc == NULL) {
1192: error("channel_post_auth_listener: channel_new failed");
1.121 markus 1193: xfree(name);
1.113 markus 1194: close(newsock);
1195: }
1.73 markus 1196: if (compat20) {
1197: packet_start(SSH2_MSG_CHANNEL_OPEN);
1198: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1199: packet_put_int(nc->self);
1.73 markus 1200: packet_put_int(c->local_window_max);
1201: packet_put_int(c->local_maxpacket);
1202: } else {
1203: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1204: packet_put_int(nc->self);
1.73 markus 1205: }
1.41 markus 1206: packet_send();
1207: }
1208: }
1.25 markus 1209:
1.127 itojun 1210: static void
1.75 markus 1211: channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1212: {
1.114 markus 1213: int err = 0;
1.129 stevesk 1214: socklen_t sz = sizeof(err);
1.114 markus 1215:
1.75 markus 1216: if (FD_ISSET(c->sock, writeset)) {
1.114 markus 1217: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
1218: &sz) < 0) {
1219: err = errno;
1220: error("getsockopt SO_ERROR failed");
1221: }
1222: if (err == 0) {
1223: debug("channel %d: connected", c->self);
1224: c->type = SSH_CHANNEL_OPEN;
1225: if (compat20) {
1226: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1227: packet_put_int(c->remote_id);
1228: packet_put_int(c->self);
1229: packet_put_int(c->local_window);
1230: packet_put_int(c->local_maxpacket);
1231: } else {
1232: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1233: packet_put_int(c->remote_id);
1234: packet_put_int(c->self);
1235: }
1.75 markus 1236: } else {
1.114 markus 1237: debug("channel %d: not connected: %s",
1238: c->self, strerror(err));
1239: if (compat20) {
1240: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1241: packet_put_int(c->remote_id);
1242: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1243: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1244: packet_put_cstring(strerror(err));
1245: packet_put_cstring("");
1246: }
1.75 markus 1247: } else {
1.114 markus 1248: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1249: packet_put_int(c->remote_id);
1.75 markus 1250: }
1.114 markus 1251: chan_mark_dead(c);
1.75 markus 1252: }
1.114 markus 1253: packet_send();
1.75 markus 1254: }
1255: }
1256:
1.127 itojun 1257: static int
1.41 markus 1258: channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1259: {
1260: char buf[16*1024];
1261: int len;
1.25 markus 1262:
1.118 markus 1263: if (c->rfd != -1 &&
1.41 markus 1264: FD_ISSET(c->rfd, readset)) {
1265: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1266: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1267: return 1;
1.41 markus 1268: if (len <= 0) {
1.51 markus 1269: debug("channel %d: read<=0 rfd %d len %d",
1.41 markus 1270: c->self, c->rfd, len);
1.104 markus 1271: if (c->type != SSH_CHANNEL_OPEN) {
1272: debug("channel %d: not open", c->self);
1.113 markus 1273: chan_mark_dead(c);
1.103 markus 1274: return -1;
1.104 markus 1275: } else if (compat13) {
1.41 markus 1276: buffer_consume(&c->output, buffer_len(&c->output));
1277: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.121 markus 1278: debug("channel %d: input draining.", c->self);
1.25 markus 1279: } else {
1.41 markus 1280: chan_read_failed(c);
1.25 markus 1281: }
1.41 markus 1282: return -1;
1283: }
1.143 deraadt 1284: if (c->input_filter != NULL) {
1.66 markus 1285: if (c->input_filter(c, buf, len) == -1) {
1.105 markus 1286: debug("channel %d: filter stops", c->self);
1.65 markus 1287: chan_read_failed(c);
1288: }
1289: } else {
1290: buffer_append(&c->input, buf, len);
1291: }
1.41 markus 1292: }
1293: return 1;
1294: }
1.127 itojun 1295: static int
1.41 markus 1296: channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1297: {
1.95 markus 1298: struct termios tio;
1.134 markus 1299: u_char *data;
1300: u_int dlen;
1.41 markus 1301: int len;
1.25 markus 1302:
1.41 markus 1303: /* Send buffered output data to the socket. */
1.118 markus 1304: if (c->wfd != -1 &&
1.41 markus 1305: FD_ISSET(c->wfd, writeset) &&
1306: buffer_len(&c->output) > 0) {
1.134 markus 1307: data = buffer_ptr(&c->output);
1308: dlen = buffer_len(&c->output);
1309: len = write(c->wfd, data, dlen);
1.53 markus 1310: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1311: return 1;
1.41 markus 1312: if (len <= 0) {
1.104 markus 1313: if (c->type != SSH_CHANNEL_OPEN) {
1314: debug("channel %d: not open", c->self);
1.113 markus 1315: chan_mark_dead(c);
1.104 markus 1316: return -1;
1317: } else if (compat13) {
1.41 markus 1318: buffer_consume(&c->output, buffer_len(&c->output));
1.121 markus 1319: debug("channel %d: input draining.", c->self);
1.41 markus 1320: c->type = SSH_CHANNEL_INPUT_DRAINING;
1321: } else {
1322: chan_write_failed(c);
1323: }
1324: return -1;
1.91 markus 1325: }
1.134 markus 1326: if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
1.91 markus 1327: if (tcgetattr(c->wfd, &tio) == 0 &&
1328: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1329: /*
1330: * Simulate echo to reduce the impact of
1.96 markus 1331: * traffic analysis. We need to match the
1.95 markus 1332: * size of a SSH2_MSG_CHANNEL_DATA message
1333: * (4 byte channel id + data)
1.91 markus 1334: */
1.95 markus 1335: packet_send_ignore(4 + len);
1.91 markus 1336: packet_send();
1337: }
1.25 markus 1338: }
1.41 markus 1339: buffer_consume(&c->output, len);
1.44 markus 1340: if (compat20 && len > 0) {
1341: c->local_consumed += len;
1342: }
1343: }
1344: return 1;
1345: }
1.127 itojun 1346: static int
1.44 markus 1347: channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1348: {
1349: char buf[16*1024];
1350: int len;
1351:
1.45 markus 1352: /** XXX handle drain efd, too */
1.44 markus 1353: if (c->efd != -1) {
1354: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1355: FD_ISSET(c->efd, writeset) &&
1356: buffer_len(&c->extended) > 0) {
1357: len = write(c->efd, buffer_ptr(&c->extended),
1358: buffer_len(&c->extended));
1.70 markus 1359: debug2("channel %d: written %d to efd %d",
1.44 markus 1360: c->self, len, c->efd);
1.93 markus 1361: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1362: return 1;
1363: if (len <= 0) {
1364: debug2("channel %d: closing write-efd %d",
1365: c->self, c->efd);
1.132 markus 1366: channel_close_fd(&c->efd);
1.93 markus 1367: } else {
1.44 markus 1368: buffer_consume(&c->extended, len);
1369: c->local_consumed += len;
1370: }
1371: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1372: FD_ISSET(c->efd, readset)) {
1373: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1374: debug2("channel %d: read %d from efd %d",
1.44 markus 1375: c->self, len, c->efd);
1.93 markus 1376: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1377: return 1;
1378: if (len <= 0) {
1379: debug2("channel %d: closing read-efd %d",
1.45 markus 1380: c->self, c->efd);
1.132 markus 1381: channel_close_fd(&c->efd);
1.93 markus 1382: } else {
1.44 markus 1383: buffer_append(&c->extended, buf, len);
1.93 markus 1384: }
1.44 markus 1385: }
1386: }
1387: return 1;
1388: }
1.127 itojun 1389: static int
1.93 markus 1390: channel_check_window(Channel *c)
1.44 markus 1391: {
1.104 markus 1392: if (c->type == SSH_CHANNEL_OPEN &&
1393: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.44 markus 1394: c->local_window < c->local_window_max/2 &&
1395: c->local_consumed > 0) {
1396: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1397: packet_put_int(c->remote_id);
1398: packet_put_int(c->local_consumed);
1399: packet_send();
1.70 markus 1400: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1401: c->self, c->local_window,
1402: c->local_consumed);
1403: c->local_window += c->local_consumed;
1404: c->local_consumed = 0;
1.1 deraadt 1405: }
1.41 markus 1406: return 1;
1.1 deraadt 1407: }
1408:
1.127 itojun 1409: static void
1.41 markus 1410: channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
1411: {
1.137 markus 1412: if (c->delayed)
1413: return;
1.41 markus 1414: channel_handle_rfd(c, readset, writeset);
1415: channel_handle_wfd(c, readset, writeset);
1416: }
1.1 deraadt 1417:
1.127 itojun 1418: static void
1.44 markus 1419: channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset)
1420: {
1.137 markus 1421: if (c->delayed)
1422: return;
1.44 markus 1423: channel_handle_rfd(c, readset, writeset);
1424: channel_handle_wfd(c, readset, writeset);
1425: channel_handle_efd(c, readset, writeset);
1.93 markus 1426:
1427: channel_check_window(c);
1.44 markus 1428: }
1429:
1.127 itojun 1430: static void
1.41 markus 1431: channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1.1 deraadt 1432: {
1.41 markus 1433: int len;
1434: /* Send buffered output data to the socket. */
1435: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1436: len = write(c->sock, buffer_ptr(&c->output),
1437: buffer_len(&c->output));
1438: if (len <= 0)
1439: buffer_consume(&c->output, buffer_len(&c->output));
1440: else
1441: buffer_consume(&c->output, len);
1442: }
1443: }
1.25 markus 1444:
1.127 itojun 1445: static void
1.44 markus 1446: channel_handler_init_20(void)
1447: {
1448: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
1.51 markus 1449: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1450: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1451: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1452: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1453: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1454: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1455: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1456:
1457: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
1458: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1459: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1460: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1461: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1462: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1463: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2;
1.44 markus 1464: }
1465:
1.127 itojun 1466: static void
1.41 markus 1467: channel_handler_init_13(void)
1468: {
1469: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1470: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1471: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1472: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1473: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1474: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1475: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1476: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1477: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1478:
1.41 markus 1479: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1480: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1481: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1482: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1483: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1484: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1485: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
1.41 markus 1486: }
1.25 markus 1487:
1.127 itojun 1488: static void
1.41 markus 1489: channel_handler_init_15(void)
1490: {
1491: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
1.51 markus 1492: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1493: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1494: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1495: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1496: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1497: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1498:
1.41 markus 1499: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1500: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1501: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1502: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1.75 markus 1503: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1504: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
1.41 markus 1505: }
1.27 markus 1506:
1.127 itojun 1507: static void
1.41 markus 1508: channel_handler_init(void)
1509: {
1510: int i;
1511: for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1512: channel_pre[i] = NULL;
1513: channel_post[i] = NULL;
1514: }
1.44 markus 1515: if (compat20)
1516: channel_handler_init_20();
1517: else if (compat13)
1.41 markus 1518: channel_handler_init_13();
1519: else
1520: channel_handler_init_15();
1521: }
1.25 markus 1522:
1.140 markus 1523: /* gc dead channels */
1524: static void
1525: channel_garbage_collect(Channel *c)
1526: {
1527: if (c == NULL)
1528: return;
1529: if (c->detach_user != NULL) {
1530: if (!chan_is_dead(c, 0))
1531: return;
1532: debug("channel %d: gc: notify user", c->self);
1533: c->detach_user(c->self, NULL);
1534: /* if we still have a callback */
1535: if (c->detach_user != NULL)
1536: return;
1537: debug("channel %d: gc: user detached", c->self);
1538: }
1539: if (!chan_is_dead(c, 1))
1540: return;
1541: debug("channel %d: garbage collecting", c->self);
1542: channel_free(c);
1543: }
1544:
1.127 itojun 1545: static void
1.41 markus 1546: channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1547: {
1548: static int did_init = 0;
1549: int i;
1550: Channel *c;
1.25 markus 1551:
1.41 markus 1552: if (!did_init) {
1553: channel_handler_init();
1554: did_init = 1;
1555: }
1556: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1557: c = channels[i];
1558: if (c == NULL)
1.41 markus 1559: continue;
1.118 markus 1560: if (ftab[c->type] != NULL)
1561: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1562: channel_garbage_collect(c);
1.1 deraadt 1563: }
1564: }
1565:
1.121 markus 1566: /*
1567: * Allocate/update select bitmasks and add any bits relevant to channels in
1568: * select bitmasks.
1569: */
1.49 markus 1570: void
1.100 markus 1571: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.132 markus 1572: int *nallocp, int rekeying)
1.41 markus 1573: {
1.84 markus 1574: int n;
1575: u_int sz;
1576:
1577: n = MAX(*maxfdp, channel_max_fd);
1578:
1579: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.132 markus 1580: /* perhaps check sz < nalloc/2 and shrink? */
1581: if (*readsetp == NULL || sz > *nallocp) {
1582: *readsetp = xrealloc(*readsetp, sz);
1583: *writesetp = xrealloc(*writesetp, sz);
1584: *nallocp = sz;
1.84 markus 1585: }
1.132 markus 1586: *maxfdp = n;
1.84 markus 1587: memset(*readsetp, 0, sz);
1588: memset(*writesetp, 0, sz);
1589:
1.100 markus 1590: if (!rekeying)
1591: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1592: }
1593:
1.121 markus 1594: /*
1595: * After select, perform any appropriate operations for channels which have
1596: * events pending.
1597: */
1.49 markus 1598: void
1.41 markus 1599: channel_after_select(fd_set * readset, fd_set * writeset)
1600: {
1601: channel_handler(channel_post, readset, writeset);
1602: }
1603:
1.121 markus 1604:
1.84 markus 1605: /* If there is data to send to the connection, enqueue some of it now. */
1.1 deraadt 1606:
1.49 markus 1607: void
1.142 itojun 1608: channel_output_poll(void)
1.1 deraadt 1609: {
1.25 markus 1610: int len, i;
1.41 markus 1611: Channel *c;
1.1 deraadt 1612:
1.25 markus 1613: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1614: c = channels[i];
1615: if (c == NULL)
1616: continue;
1.37 markus 1617:
1.121 markus 1618: /*
1619: * We are only interested in channels that can have buffered
1620: * incoming data.
1621: */
1.37 markus 1622: if (compat13) {
1.41 markus 1623: if (c->type != SSH_CHANNEL_OPEN &&
1624: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1625: continue;
1626: } else {
1.41 markus 1627: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1628: continue;
1629: }
1.46 markus 1630: if (compat20 &&
1631: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1632: /* XXX is this true? */
1.140 markus 1633: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1634: continue;
1635: }
1.25 markus 1636:
1637: /* Get the amount of buffered data for this channel. */
1.93 markus 1638: if ((c->istate == CHAN_INPUT_OPEN ||
1639: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1640: (len = buffer_len(&c->input)) > 0) {
1.121 markus 1641: /*
1642: * Send some data for the other side over the secure
1643: * connection.
1644: */
1.44 markus 1645: if (compat20) {
1646: if (len > c->remote_window)
1647: len = c->remote_window;
1648: if (len > c->remote_maxpacket)
1649: len = c->remote_maxpacket;
1.25 markus 1650: } else {
1.44 markus 1651: if (packet_is_interactive()) {
1652: if (len > 1024)
1653: len = 512;
1654: } else {
1655: /* Keep the packets at reasonable size. */
1656: if (len > packet_get_maxsize()/2)
1657: len = packet_get_maxsize()/2;
1658: }
1.25 markus 1659: }
1.41 markus 1660: if (len > 0) {
1.44 markus 1661: packet_start(compat20 ?
1662: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1663: packet_put_int(c->remote_id);
1664: packet_put_string(buffer_ptr(&c->input), len);
1665: packet_send();
1666: buffer_consume(&c->input, len);
1667: c->remote_window -= len;
1668: }
1669: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1670: if (compat13)
1671: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1672: /*
1673: * input-buffer is empty and read-socket shutdown:
1674: * tell peer, that we will not send more data: send IEOF
1675: */
1.41 markus 1676: chan_ibuf_empty(c);
1.25 markus 1677: }
1.44 markus 1678: /* Send extended data, i.e. stderr */
1679: if (compat20 &&
1680: c->remote_window > 0 &&
1681: (len = buffer_len(&c->extended)) > 0 &&
1682: c->extended_usage == CHAN_EXTENDED_READ) {
1.93 markus 1683: debug2("channel %d: rwin %d elen %d euse %d",
1684: c->self, c->remote_window, buffer_len(&c->extended),
1685: c->extended_usage);
1.44 markus 1686: if (len > c->remote_window)
1687: len = c->remote_window;
1688: if (len > c->remote_maxpacket)
1689: len = c->remote_maxpacket;
1690: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1691: packet_put_int(c->remote_id);
1692: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1693: packet_put_string(buffer_ptr(&c->extended), len);
1694: packet_send();
1695: buffer_consume(&c->extended, len);
1696: c->remote_window -= len;
1.93 markus 1697: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1698: }
1.25 markus 1699: }
1.1 deraadt 1700: }
1701:
1.121 markus 1702:
1703: /* -- protocol input */
1.1 deraadt 1704:
1.49 markus 1705: void
1.69 markus 1706: channel_input_data(int type, int plen, void *ctxt)
1.1 deraadt 1707: {
1.37 markus 1708: int id;
1.25 markus 1709: char *data;
1.77 markus 1710: u_int data_len;
1.41 markus 1711: Channel *c;
1.25 markus 1712:
1713: /* Get the channel number and verify it. */
1.37 markus 1714: id = packet_get_int();
1.41 markus 1715: c = channel_lookup(id);
1716: if (c == NULL)
1.37 markus 1717: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 1718:
1719: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 1720: if (c->type != SSH_CHANNEL_OPEN &&
1721: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 1722: return;
1723:
1724: /* same for protocol 1.5 if output end is no longer open */
1.41 markus 1725: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
1.25 markus 1726: return;
1727:
1728: /* Get the data. */
1729: data = packet_get_string(&data_len);
1.48 markus 1730: packet_done();
1.41 markus 1731:
1.143 deraadt 1732: if (compat20) {
1.44 markus 1733: if (data_len > c->local_maxpacket) {
1734: log("channel %d: rcvd big packet %d, maxpack %d",
1735: c->self, data_len, c->local_maxpacket);
1736: }
1737: if (data_len > c->local_window) {
1738: log("channel %d: rcvd too much data %d, win %d",
1739: c->self, data_len, c->local_window);
1740: xfree(data);
1741: return;
1742: }
1743: c->local_window -= data_len;
1744: }else{
1745: packet_integrity_check(plen, 4 + 4 + data_len, type);
1746: }
1.41 markus 1747: buffer_append(&c->output, data, data_len);
1.25 markus 1748: xfree(data);
1.1 deraadt 1749: }
1.121 markus 1750:
1.49 markus 1751: void
1.69 markus 1752: channel_input_extended_data(int type, int plen, void *ctxt)
1.44 markus 1753: {
1754: int id;
1755: int tcode;
1756: char *data;
1.77 markus 1757: u_int data_len;
1.44 markus 1758: Channel *c;
1759:
1760: /* Get the channel number and verify it. */
1761: id = packet_get_int();
1762: c = channel_lookup(id);
1763:
1764: if (c == NULL)
1765: packet_disconnect("Received extended_data for bad channel %d.", id);
1766: if (c->type != SSH_CHANNEL_OPEN) {
1767: log("channel %d: ext data for non open", id);
1768: return;
1769: }
1770: tcode = packet_get_int();
1771: if (c->efd == -1 ||
1772: c->extended_usage != CHAN_EXTENDED_WRITE ||
1773: tcode != SSH2_EXTENDED_DATA_STDERR) {
1774: log("channel %d: bad ext data", c->self);
1775: return;
1776: }
1777: data = packet_get_string(&data_len);
1.48 markus 1778: packet_done();
1.44 markus 1779: if (data_len > c->local_window) {
1780: log("channel %d: rcvd too much extended_data %d, win %d",
1781: c->self, data_len, c->local_window);
1782: xfree(data);
1783: return;
1784: }
1.70 markus 1785: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 1786: c->local_window -= data_len;
1787: buffer_append(&c->extended, data, data_len);
1788: xfree(data);
1789: }
1790:
1.49 markus 1791: void
1.69 markus 1792: channel_input_ieof(int type, int plen, void *ctxt)
1.41 markus 1793: {
1794: int id;
1795: Channel *c;
1796:
1797: packet_integrity_check(plen, 4, type);
1798:
1799: id = packet_get_int();
1800: c = channel_lookup(id);
1801: if (c == NULL)
1802: packet_disconnect("Received ieof for nonexistent channel %d.", id);
1803: chan_rcvd_ieof(c);
1.133 markus 1804:
1805: /* XXX force input close */
1806: if (c->force_drain) {
1807: debug("channel %d: FORCE input drain", c->self);
1808: c->istate = CHAN_INPUT_WAIT_DRAIN;
1809: }
1810:
1.41 markus 1811: }
1.1 deraadt 1812:
1.49 markus 1813: void
1.69 markus 1814: channel_input_close(int type, int plen, void *ctxt)
1.1 deraadt 1815: {
1.41 markus 1816: int id;
1817: Channel *c;
1.1 deraadt 1818:
1.41 markus 1819: packet_integrity_check(plen, 4, type);
1820:
1821: id = packet_get_int();
1822: c = channel_lookup(id);
1823: if (c == NULL)
1824: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 1825:
1826: /*
1827: * Send a confirmation that we have closed the channel and no more
1828: * data is coming for it.
1829: */
1.25 markus 1830: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 1831: packet_put_int(c->remote_id);
1.25 markus 1832: packet_send();
1833:
1.27 markus 1834: /*
1835: * If the channel is in closed state, we have sent a close request,
1836: * and the other side will eventually respond with a confirmation.
1837: * Thus, we cannot free the channel here, because then there would be
1838: * no-one to receive the confirmation. The channel gets freed when
1839: * the confirmation arrives.
1840: */
1.41 markus 1841: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 1842: /*
1843: * Not a closed channel - mark it as draining, which will
1844: * cause it to be freed later.
1845: */
1.41 markus 1846: buffer_consume(&c->input, buffer_len(&c->input));
1847: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 1848: }
1.1 deraadt 1849: }
1850:
1.41 markus 1851: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.49 markus 1852: void
1.69 markus 1853: channel_input_oclose(int type, int plen, void *ctxt)
1.41 markus 1854: {
1855: int id = packet_get_int();
1856: Channel *c = channel_lookup(id);
1857: packet_integrity_check(plen, 4, type);
1858: if (c == NULL)
1859: packet_disconnect("Received oclose for nonexistent channel %d.", id);
1860: chan_rcvd_oclose(c);
1861: }
1.1 deraadt 1862:
1.49 markus 1863: void
1.69 markus 1864: channel_input_close_confirmation(int type, int plen, void *ctxt)
1.1 deraadt 1865: {
1.41 markus 1866: int id = packet_get_int();
1867: Channel *c = channel_lookup(id);
1.1 deraadt 1868:
1.48 markus 1869: packet_done();
1.41 markus 1870: if (c == NULL)
1871: packet_disconnect("Received close confirmation for "
1872: "out-of-range channel %d.", id);
1873: if (c->type != SSH_CHANNEL_CLOSED)
1874: packet_disconnect("Received close confirmation for "
1875: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 1876: channel_free(c);
1.1 deraadt 1877: }
1878:
1.49 markus 1879: void
1.69 markus 1880: channel_input_open_confirmation(int type, int plen, void *ctxt)
1.1 deraadt 1881: {
1.41 markus 1882: int id, remote_id;
1883: Channel *c;
1.1 deraadt 1884:
1.44 markus 1885: if (!compat20)
1886: packet_integrity_check(plen, 4 + 4, type);
1.25 markus 1887:
1.41 markus 1888: id = packet_get_int();
1889: c = channel_lookup(id);
1.25 markus 1890:
1.41 markus 1891: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1892: packet_disconnect("Received open confirmation for "
1893: "non-opening channel %d.", id);
1894: remote_id = packet_get_int();
1.27 markus 1895: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 1896: c->remote_id = remote_id;
1897: c->type = SSH_CHANNEL_OPEN;
1.44 markus 1898:
1899: if (compat20) {
1900: c->remote_window = packet_get_int();
1901: c->remote_maxpacket = packet_get_int();
1.48 markus 1902: packet_done();
1.44 markus 1903: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1904: debug2("callback start");
1.44 markus 1905: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1906: debug2("callback done");
1.44 markus 1907: }
1908: debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1909: c->remote_window, c->remote_maxpacket);
1910: }
1.1 deraadt 1911: }
1912:
1.127 itojun 1913: static char *
1.114 markus 1914: reason2txt(int reason)
1915: {
1.143 deraadt 1916: switch (reason) {
1.114 markus 1917: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1918: return "administratively prohibited";
1919: case SSH2_OPEN_CONNECT_FAILED:
1920: return "connect failed";
1921: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1922: return "unknown channel type";
1923: case SSH2_OPEN_RESOURCE_SHORTAGE:
1924: return "resource shortage";
1925: }
1.117 stevesk 1926: return "unknown reason";
1.114 markus 1927: }
1928:
1.49 markus 1929: void
1.69 markus 1930: channel_input_open_failure(int type, int plen, void *ctxt)
1.1 deraadt 1931: {
1.86 markus 1932: int id, reason;
1933: char *msg = NULL, *lang = NULL;
1.41 markus 1934: Channel *c;
1935:
1.44 markus 1936: if (!compat20)
1937: packet_integrity_check(plen, 4, type);
1.41 markus 1938:
1939: id = packet_get_int();
1940: c = channel_lookup(id);
1.25 markus 1941:
1.41 markus 1942: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1943: packet_disconnect("Received open failure for "
1944: "non-opening channel %d.", id);
1.44 markus 1945: if (compat20) {
1.86 markus 1946: reason = packet_get_int();
1.110 markus 1947: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 1948: msg = packet_get_string(NULL);
1949: lang = packet_get_string(NULL);
1950: }
1.48 markus 1951: packet_done();
1.114 markus 1952: log("channel %d: open failed: %s%s%s", id,
1953: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 1954: if (msg != NULL)
1955: xfree(msg);
1956: if (lang != NULL)
1957: xfree(lang);
1.44 markus 1958: }
1.25 markus 1959: /* Free the channel. This will also close the socket. */
1.113 markus 1960: channel_free(c);
1.1 deraadt 1961: }
1962:
1.44 markus 1963: void
1.69 markus 1964: channel_input_channel_request(int type, int plen, void *ctxt)
1.44 markus 1965: {
1966: int id;
1967: Channel *c;
1968:
1969: id = packet_get_int();
1970: c = channel_lookup(id);
1971:
1972: if (c == NULL ||
1973: (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1974: packet_disconnect("Received request for "
1975: "non-open channel %d.", id);
1976: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1977: debug2("callback start");
1.44 markus 1978: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1979: debug2("callback done");
1.44 markus 1980: } else {
1981: char *service = packet_get_string(NULL);
1.94 markus 1982: debug("channel %d: rcvd request for %s", c->self, service);
1.70 markus 1983: debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
1.44 markus 1984: xfree(service);
1985: }
1986: }
1987:
1.121 markus 1988: void
1989: channel_input_window_adjust(int type, int plen, void *ctxt)
1990: {
1991: Channel *c;
1992: int id, adjust;
1993:
1994: if (!compat20)
1995: return;
1996:
1997: /* Get the channel number and verify it. */
1998: id = packet_get_int();
1999: c = channel_lookup(id);
1.1 deraadt 2000:
1.121 markus 2001: if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
2002: log("Received window adjust for "
2003: "non-open channel %d.", id);
2004: return;
2005: }
2006: adjust = packet_get_int();
2007: packet_done();
2008: debug2("channel %d: rcvd adjust %d", id, adjust);
2009: c->remote_window += adjust;
2010: }
1.1 deraadt 2011:
1.121 markus 2012: void
2013: channel_input_port_open(int type, int plen, void *ctxt)
1.1 deraadt 2014: {
1.121 markus 2015: Channel *c = NULL;
2016: u_short host_port;
2017: char *host, *originator_string;
2018: int remote_id, sock = -1;
2019:
2020: remote_id = packet_get_int();
2021: host = packet_get_string(NULL);
2022: host_port = packet_get_int();
1.25 markus 2023:
1.121 markus 2024: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2025: originator_string = packet_get_string(NULL);
2026: } else {
2027: originator_string = xstrdup("unknown (remote did not supply name)");
2028: }
2029: packet_done();
2030: sock = channel_connect_to(host, host_port);
2031: if (sock != -1) {
2032: c = channel_new("connected socket",
2033: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2034: originator_string, 1);
2035: if (c == NULL) {
2036: error("channel_input_port_open: channel_new failed");
2037: close(sock);
2038: } else {
2039: c->remote_id = remote_id;
1.25 markus 2040: }
2041: }
1.121 markus 2042: if (c == NULL) {
2043: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2044: packet_put_int(remote_id);
2045: packet_send();
2046: }
2047: xfree(host);
1.1 deraadt 2048: }
2049:
1.121 markus 2050:
2051: /* -- tcp forwarding */
1.135 markus 2052:
2053: void
2054: channel_set_af(int af)
2055: {
2056: IPv4or6 = af;
2057: }
1.121 markus 2058:
1.27 markus 2059: /*
2060: * Initiate forwarding of connections to local port "port" through the secure
2061: * channel to host:port from remote side.
2062: */
1.87 markus 2063: int
1.73 markus 2064: channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
2065: u_short port_to_connect, int gateway_ports)
2066: {
1.87 markus 2067: return channel_request_forwarding(
1.73 markus 2068: NULL, listen_port,
2069: host_to_connect, port_to_connect,
2070: gateway_ports, /*remote_fwd*/ 0);
2071: }
1.1 deraadt 2072:
1.73 markus 2073: /*
2074: * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
2075: * (SSH_CHANNEL_RPORT_LISTENER).
2076: */
1.87 markus 2077: int
1.73 markus 2078: channel_request_forwarding(
2079: const char *listen_address, u_short listen_port,
2080: const char *host_to_connect, u_short port_to_connect,
2081: int gateway_ports, int remote_fwd)
1.25 markus 2082: {
1.113 markus 2083: Channel *c;
1.121 markus 2084: int success, sock, on = 1, type;
1.35 markus 2085: struct addrinfo hints, *ai, *aitop;
2086: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.73 markus 2087: const char *host;
1.28 markus 2088: struct linger linger;
1.25 markus 2089:
1.87 markus 2090: success = 0;
2091:
1.73 markus 2092: if (remote_fwd) {
2093: host = listen_address;
1.121 markus 2094: type = SSH_CHANNEL_RPORT_LISTENER;
1.73 markus 2095: } else {
2096: host = host_to_connect;
1.121 markus 2097: type = SSH_CHANNEL_PORT_LISTENER;
1.73 markus 2098: }
2099:
1.113 markus 2100: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2101: error("Forward host name too long.");
2102: return success;
2103: }
1.25 markus 2104:
1.73 markus 2105: /* XXX listen_address is currently ignored */
1.28 markus 2106: /*
1.35 markus 2107: * getaddrinfo returns a loopback address if the hostname is
2108: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2109: */
1.35 markus 2110: memset(&hints, 0, sizeof(hints));
2111: hints.ai_family = IPv4or6;
2112: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2113: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2114: snprintf(strport, sizeof strport, "%d", listen_port);
1.35 markus 2115: if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2116: packet_disconnect("getaddrinfo: fatal error");
2117:
2118: for (ai = aitop; ai; ai = ai->ai_next) {
2119: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2120: continue;
2121: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2122: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.73 markus 2123: error("channel_request_forwarding: getnameinfo failed");
1.35 markus 2124: continue;
2125: }
2126: /* Create a port to listen for the host. */
2127: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2128: if (sock < 0) {
2129: /* this is no error since kernel may not support ipv6 */
2130: verbose("socket: %.100s", strerror(errno));
2131: continue;
2132: }
2133: /*
2134: * Set socket options. We would like the socket to disappear
2135: * as soon as it has been closed for whatever reason.
2136: */
2137: setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
2138: linger.l_onoff = 1;
2139: linger.l_linger = 5;
2140: setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
2141: debug("Local forwarding listening on %s port %s.", ntop, strport);
2142:
2143: /* Bind the socket to the address. */
2144: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2145: /* address can be in use ipv6 address is already bound */
2146: verbose("bind: %.100s", strerror(errno));
2147: close(sock);
2148: continue;
2149: }
2150: /* Start listening for connections on the socket. */
2151: if (listen(sock, 5) < 0) {
2152: error("listen: %.100s", strerror(errno));
2153: close(sock);
2154: continue;
2155: }
2156: /* Allocate a channel number for the socket. */
1.121 markus 2157: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2158: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.71 markus 2159: 0, xstrdup("port listener"), 1);
1.113 markus 2160: if (c == NULL) {
2161: error("channel_request_forwarding: channel_new failed");
2162: close(sock);
2163: continue;
2164: }
2165: strlcpy(c->path, host, sizeof(c->path));
2166: c->host_port = port_to_connect;
2167: c->listening_port = listen_port;
1.35 markus 2168: success = 1;
2169: }
2170: if (success == 0)
1.87 markus 2171: error("channel_request_forwarding: cannot listen to port: %d",
2172: listen_port);
1.35 markus 2173: freeaddrinfo(aitop);
1.87 markus 2174: return success;
1.25 markus 2175: }
1.1 deraadt 2176:
1.27 markus 2177: /*
2178: * Initiate forwarding of connections to port "port" on remote host through
2179: * the secure channel to host:port from local side.
2180: */
1.1 deraadt 2181:
1.49 markus 2182: void
1.73 markus 2183: channel_request_remote_forwarding(u_short listen_port,
2184: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2185: {
1.73 markus 2186: int payload_len, type, success = 0;
2187:
1.25 markus 2188: /* Record locally that connection to this host/port is permitted. */
2189: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2190: fatal("channel_request_remote_forwarding: too many forwards");
2191:
2192: /* Send the forward request to the remote side. */
1.44 markus 2193: if (compat20) {
2194: const char *address_to_bind = "0.0.0.0";
2195: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2196: packet_put_cstring("tcpip-forward");
2197: packet_put_char(0); /* boolean: want reply */
2198: packet_put_cstring(address_to_bind);
2199: packet_put_int(listen_port);
1.73 markus 2200: packet_send();
2201: packet_write_wait();
2202: /* Assume that server accepts the request */
2203: success = 1;
1.44 markus 2204: } else {
2205: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2206: packet_put_int(listen_port);
2207: packet_put_cstring(host_to_connect);
1.44 markus 2208: packet_put_int(port_to_connect);
2209: packet_send();
2210: packet_write_wait();
1.73 markus 2211:
2212: /* Wait for response from the remote side. */
2213: type = packet_read(&payload_len);
2214: switch (type) {
2215: case SSH_SMSG_SUCCESS:
2216: success = 1;
2217: break;
2218: case SSH_SMSG_FAILURE:
2219: log("Warning: Server denied remote port forwarding.");
2220: break;
2221: default:
2222: /* Unknown packet */
2223: packet_disconnect("Protocol error for port forward request:"
2224: "received packet type %d.", type);
2225: }
2226: }
2227: if (success) {
2228: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2229: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2230: permitted_opens[num_permitted_opens].listen_port = listen_port;
2231: num_permitted_opens++;
1.44 markus 2232: }
1.1 deraadt 2233: }
2234:
1.27 markus 2235: /*
2236: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2237: * listening for the port, and sends back a success reply (or disconnect
2238: * message if there was an error). This never returns if there was an error.
2239: */
1.1 deraadt 2240:
1.49 markus 2241: void
1.56 markus 2242: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2243: {
1.31 markus 2244: u_short port, host_port;
1.25 markus 2245: char *hostname;
1.1 deraadt 2246:
1.25 markus 2247: /* Get arguments from the packet. */
2248: port = packet_get_int();
2249: hostname = packet_get_string(NULL);
2250: host_port = packet_get_int();
2251:
1.27 markus 2252: /*
2253: * Check that an unprivileged user is not trying to forward a
2254: * privileged port.
2255: */
1.25 markus 2256: if (port < IPPORT_RESERVED && !is_root)
2257: packet_disconnect("Requested forwarding of port %d but user is not root.",
2258: port);
1.73 markus 2259: /* Initiate forwarding */
1.56 markus 2260: channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
1.25 markus 2261:
2262: /* Free the argument string. */
2263: xfree(hostname);
1.1 deraadt 2264: }
2265:
1.99 markus 2266: /*
2267: * Permits opening to any host/port if permitted_opens[] is empty. This is
2268: * usually called by the server, because the user could connect to any port
2269: * anyway, and the server has no way to know but to trust the client anyway.
2270: */
2271: void
1.142 itojun 2272: channel_permit_all_opens(void)
1.99 markus 2273: {
2274: if (num_permitted_opens == 0)
2275: all_opens_permitted = 1;
2276: }
2277:
1.101 markus 2278: void
1.99 markus 2279: channel_add_permitted_opens(char *host, int port)
2280: {
2281: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2282: fatal("channel_request_remote_forwarding: too many forwards");
2283: debug("allow port forwarding to host %s port %d", host, port);
2284:
2285: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2286: permitted_opens[num_permitted_opens].port_to_connect = port;
2287: num_permitted_opens++;
2288:
2289: all_opens_permitted = 0;
2290: }
2291:
1.101 markus 2292: void
1.99 markus 2293: channel_clear_permitted_opens(void)
2294: {
2295: int i;
2296:
2297: for (i = 0; i < num_permitted_opens; i++)
2298: xfree(permitted_opens[i].host_to_connect);
2299: num_permitted_opens = 0;
2300:
2301: }
2302:
2303:
2304: /* return socket to remote host, port */
1.127 itojun 2305: static int
1.99 markus 2306: connect_to(const char *host, u_short port)
1.41 markus 2307: {
2308: struct addrinfo hints, *ai, *aitop;
2309: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2310: int gaierr;
2311: int sock = -1;
2312:
2313: memset(&hints, 0, sizeof(hints));
2314: hints.ai_family = IPv4or6;
2315: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2316: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2317: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2318: error("connect_to %.100s: unknown host (%s)", host,
2319: gai_strerror(gaierr));
1.41 markus 2320: return -1;
2321: }
2322: for (ai = aitop; ai; ai = ai->ai_next) {
2323: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2324: continue;
2325: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2326: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2327: error("connect_to: getnameinfo failed");
1.41 markus 2328: continue;
2329: }
2330: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2331: if (sock < 0) {
2332: error("socket: %.100s", strerror(errno));
2333: continue;
2334: }
1.80 markus 2335: if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
1.75 markus 2336: fatal("connect_to: F_SETFL: %s", strerror(errno));
2337: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2338: errno != EINPROGRESS) {
1.99 markus 2339: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2340: strerror(errno));
2341: close(sock);
1.89 stevesk 2342: continue; /* fail -- try next */
1.41 markus 2343: }
2344: break; /* success */
2345:
2346: }
2347: freeaddrinfo(aitop);
2348: if (!ai) {
1.99 markus 2349: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2350: return -1;
2351: }
2352: /* success */
2353: return sock;
2354: }
1.99 markus 2355:
1.73 markus 2356: int
1.130 stevesk 2357: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2358: {
2359: int i;
1.99 markus 2360:
1.73 markus 2361: for (i = 0; i < num_permitted_opens; i++)
2362: if (permitted_opens[i].listen_port == listen_port)
1.99 markus 2363: return connect_to(
1.73 markus 2364: permitted_opens[i].host_to_connect,
2365: permitted_opens[i].port_to_connect);
1.74 markus 2366: error("WARNING: Server requests forwarding for unknown listen_port %d",
2367: listen_port);
1.73 markus 2368: return -1;
2369: }
2370:
1.99 markus 2371: /* Check if connecting to that port is permitted and connect. */
2372: int
2373: channel_connect_to(const char *host, u_short port)
2374: {
2375: int i, permit;
2376:
2377: permit = all_opens_permitted;
2378: if (!permit) {
2379: for (i = 0; i < num_permitted_opens; i++)
2380: if (permitted_opens[i].port_to_connect == port &&
2381: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2382: permit = 1;
2383:
2384: }
2385: if (!permit) {
2386: log("Received request to connect to host %.100s port %d, "
2387: "but the request was denied.", host, port);
2388: return -1;
2389: }
2390: return connect_to(host, port);
2391: }
2392:
1.121 markus 2393: /* -- X11 forwarding */
1.1 deraadt 2394:
1.27 markus 2395: /*
2396: * Creates an internet domain socket for listening for X11 connections.
1.141 stevesk 2397: * Returns a suitable display number for the DISPLAY variable, or -1 if
2398: * an error occurs.
1.27 markus 2399: */
1.141 stevesk 2400: int
2401: x11_create_display_inet(int x11_display_offset, int gateway_ports)
1.1 deraadt 2402: {
1.31 markus 2403: int display_number, sock;
2404: u_short port;
1.35 markus 2405: struct addrinfo hints, *ai, *aitop;
2406: char strport[NI_MAXSERV];
2407: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 2408:
1.33 markus 2409: for (display_number = x11_display_offset;
1.25 markus 2410: display_number < MAX_DISPLAYS;
2411: display_number++) {
2412: port = 6000 + display_number;
1.35 markus 2413: memset(&hints, 0, sizeof(hints));
2414: hints.ai_family = IPv4or6;
1.141 stevesk 2415: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
1.35 markus 2416: hints.ai_socktype = SOCK_STREAM;
2417: snprintf(strport, sizeof strport, "%d", port);
2418: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2419: error("getaddrinfo: %.100s", gai_strerror(gaierr));
1.141 stevesk 2420: return -1;
1.25 markus 2421: }
1.35 markus 2422: for (ai = aitop; ai; ai = ai->ai_next) {
2423: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2424: continue;
2425: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2426: if (sock < 0) {
2427: error("socket: %.100s", strerror(errno));
1.141 stevesk 2428: return -1;
1.35 markus 2429: }
2430: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2431: debug("bind port %d: %.100s", port, strerror(errno));
2432: close(sock);
2433: for (n = 0; n < num_socks; n++) {
2434: close(socks[n]);
2435: }
2436: num_socks = 0;
2437: break;
2438: }
2439: socks[num_socks++] = sock;
2440: if (num_socks == NUM_SOCKS)
2441: break;
1.25 markus 2442: }
1.83 stevesk 2443: freeaddrinfo(aitop);
1.35 markus 2444: if (num_socks > 0)
2445: break;
1.25 markus 2446: }
2447: if (display_number >= MAX_DISPLAYS) {
2448: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 2449: return -1;
1.25 markus 2450: }
2451: /* Start listening for connections on the socket. */
1.35 markus 2452: for (n = 0; n < num_socks; n++) {
2453: sock = socks[n];
2454: if (listen(sock, 5) < 0) {
2455: error("listen: %.100s", strerror(errno));
2456: close(sock);
1.141 stevesk 2457: return -1;
1.35 markus 2458: }
1.25 markus 2459: }
1.35 markus 2460:
2461: /* Allocate a channel for each socket. */
2462: for (n = 0; n < num_socks; n++) {
2463: sock = socks[n];
1.51 markus 2464: (void) channel_new("x11 listener",
2465: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2466: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.71 markus 2467: 0, xstrdup("X11 inet listener"), 1);
1.35 markus 2468: }
1.1 deraadt 2469:
1.141 stevesk 2470: /* Return the display number for the DISPLAY environment variable. */
2471: return display_number;
1.1 deraadt 2472: }
2473:
2474: #ifndef X_UNIX_PATH
2475: #define X_UNIX_PATH "/tmp/.X11-unix/X"
2476: #endif
2477:
1.127 itojun 2478: static int
1.77 markus 2479: connect_local_xsocket(u_int dnr)
1.1 deraadt 2480: {
1.25 markus 2481: static const char *const x_sockets[] = {
2482: X_UNIX_PATH "%u",
2483: "/var/X/.X11-unix/X" "%u",
2484: "/usr/spool/sockets/X11/" "%u",
2485: NULL
2486: };
2487: int sock;
2488: struct sockaddr_un addr;
2489: const char *const * path;
2490:
2491: for (path = x_sockets; *path; ++path) {
2492: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2493: if (sock < 0)
2494: error("socket: %.100s", strerror(errno));
2495: memset(&addr, 0, sizeof(addr));
2496: addr.sun_family = AF_UNIX;
2497: snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr);
2498: if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2499: return sock;
2500: close(sock);
2501: }
2502: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2503: return -1;
1.1 deraadt 2504: }
2505:
1.51 markus 2506: int
2507: x11_connect_display(void)
1.1 deraadt 2508: {
1.146 ! stevesk 2509: int display_number, sock = 0, on = 1;
1.25 markus 2510: const char *display;
1.51 markus 2511: char buf[1024], *cp;
1.35 markus 2512: struct addrinfo hints, *ai, *aitop;
2513: char strport[NI_MAXSERV];
2514: int gaierr;
1.25 markus 2515:
2516: /* Try to open a socket for the local X server. */
2517: display = getenv("DISPLAY");
2518: if (!display) {
2519: error("DISPLAY not set.");
1.51 markus 2520: return -1;
1.25 markus 2521: }
1.27 markus 2522: /*
2523: * Now we decode the value of the DISPLAY variable and make a
2524: * connection to the real X server.
2525: */
2526:
2527: /*
2528: * Check if it is a unix domain socket. Unix domain displays are in
2529: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2530: */
1.25 markus 2531: if (strncmp(display, "unix:", 5) == 0 ||
2532: display[0] == ':') {
2533: /* Connect to the unix domain socket. */
2534: if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2535: error("Could not parse display number from DISPLAY: %.100s",
2536: display);
1.51 markus 2537: return -1;
1.25 markus 2538: }
2539: /* Create a socket. */
2540: sock = connect_local_xsocket(display_number);
2541: if (sock < 0)
1.51 markus 2542: return -1;
1.25 markus 2543:
2544: /* OK, we now have a connection to the display. */
1.51 markus 2545: return sock;
1.25 markus 2546: }
1.27 markus 2547: /*
2548: * Connect to an inet socket. The DISPLAY value is supposedly
2549: * hostname:d[.s], where hostname may also be numeric IP address.
2550: */
1.145 stevesk 2551: strlcpy(buf, display, sizeof(buf));
1.25 markus 2552: cp = strchr(buf, ':');
2553: if (!cp) {
2554: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 2555: return -1;
1.25 markus 2556: }
2557: *cp = 0;
1.27 markus 2558: /* buf now contains the host name. But first we parse the display number. */
1.25 markus 2559: if (sscanf(cp + 1, "%d", &display_number) != 1) {
2560: error("Could not parse display number from DISPLAY: %.100s",
2561: display);
1.51 markus 2562: return -1;
1.25 markus 2563: }
1.35 markus 2564:
2565: /* Look up the host address */
2566: memset(&hints, 0, sizeof(hints));
2567: hints.ai_family = IPv4or6;
2568: hints.ai_socktype = SOCK_STREAM;
2569: snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2570: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2571: error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
1.51 markus 2572: return -1;
1.25 markus 2573: }
1.35 markus 2574: for (ai = aitop; ai; ai = ai->ai_next) {
2575: /* Create a socket. */
2576: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2577: if (sock < 0) {
2578: debug("socket: %.100s", strerror(errno));
1.41 markus 2579: continue;
2580: }
2581: /* Connect it to the display. */
2582: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2583: debug("connect %.100s port %d: %.100s", buf,
2584: 6000 + display_number, strerror(errno));
2585: close(sock);
2586: continue;
2587: }
2588: /* Success */
2589: break;
1.35 markus 2590: }
2591: freeaddrinfo(aitop);
2592: if (!ai) {
1.49 markus 2593: error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
1.35 markus 2594: strerror(errno));
1.51 markus 2595: return -1;
1.25 markus 2596: }
1.146 ! stevesk 2597: if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on) == -1)
! 2598: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
1.51 markus 2599: return sock;
2600: }
2601:
2602: /*
2603: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2604: * the remote channel number. We should do whatever we want, and respond
2605: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2606: */
2607:
2608: void
1.69 markus 2609: x11_input_open(int type, int plen, void *ctxt)
1.51 markus 2610: {
1.113 markus 2611: Channel *c = NULL;
2612: int remote_id, sock = 0;
1.51 markus 2613: char *remote_host;
1.25 markus 2614:
1.113 markus 2615: debug("Received X11 open request.");
1.51 markus 2616:
1.113 markus 2617: remote_id = packet_get_int();
1.121 markus 2618:
2619: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 2620: remote_host = packet_get_string(NULL);
1.51 markus 2621: } else {
2622: remote_host = xstrdup("unknown (remote did not supply name)");
2623: }
1.113 markus 2624: packet_done();
1.25 markus 2625:
1.51 markus 2626: /* Obtain a connection to the real X display. */
2627: sock = x11_connect_display();
1.113 markus 2628: if (sock != -1) {
2629: /* Allocate a channel for this connection. */
2630: c = channel_new("connected x11 socket",
2631: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2632: remote_host, 1);
2633: if (c == NULL) {
2634: error("x11_input_open: channel_new failed");
2635: close(sock);
2636: } else {
2637: c->remote_id = remote_id;
1.133 markus 2638: c->force_drain = 1;
1.113 markus 2639: }
2640: }
2641: if (c == NULL) {
1.51 markus 2642: /* Send refusal to the remote host. */
2643: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2644: packet_put_int(remote_id);
1.51 markus 2645: } else {
2646: /* Send a confirmation to the remote host. */
2647: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 2648: packet_put_int(remote_id);
2649: packet_put_int(c->self);
1.51 markus 2650: }
1.113 markus 2651: packet_send();
1.72 markus 2652: }
2653:
2654: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2655: void
2656: deny_input_open(int type, int plen, void *ctxt)
2657: {
2658: int rchan = packet_get_int();
1.143 deraadt 2659: switch (type) {
1.72 markus 2660: case SSH_SMSG_AGENT_OPEN:
2661: error("Warning: ssh server tried agent forwarding.");
2662: break;
2663: case SSH_SMSG_X11_OPEN:
2664: error("Warning: ssh server tried X11 forwarding.");
2665: break;
2666: default:
2667: error("deny_input_open: type %d plen %d", type, plen);
2668: break;
2669: }
2670: error("Warning: this is probably a break in attempt by a malicious server.");
2671: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2672: packet_put_int(rchan);
2673: packet_send();
1.1 deraadt 2674: }
2675:
1.27 markus 2676: /*
2677: * Requests forwarding of X11 connections, generates fake authentication
2678: * data, and enables authentication spoofing.
1.121 markus 2679: * This should be called in the client only.
1.27 markus 2680: */
1.49 markus 2681: void
1.51 markus 2682: x11_request_forwarding_with_spoofing(int client_session_id,
2683: const char *proto, const char *data)
1.1 deraadt 2684: {
1.77 markus 2685: u_int data_len = (u_int) strlen(data) / 2;
1.90 markus 2686: u_int i, value, len;
1.25 markus 2687: char *new_data;
2688: int screen_number;
2689: const char *cp;
2690: u_int32_t rand = 0;
2691:
2692: cp = getenv("DISPLAY");
2693: if (cp)
2694: cp = strchr(cp, ':');
2695: if (cp)
2696: cp = strchr(cp, '.');
2697: if (cp)
2698: screen_number = atoi(cp + 1);
2699: else
2700: screen_number = 0;
2701:
2702: /* Save protocol name. */
2703: x11_saved_proto = xstrdup(proto);
2704:
1.27 markus 2705: /*
2706: * Extract real authentication data and generate fake data of the
2707: * same length.
2708: */
1.25 markus 2709: x11_saved_data = xmalloc(data_len);
2710: x11_fake_data = xmalloc(data_len);
2711: for (i = 0; i < data_len; i++) {
2712: if (sscanf(data + 2 * i, "%2x", &value) != 1)
2713: fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2714: if (i % 4 == 0)
2715: rand = arc4random();
2716: x11_saved_data[i] = value;
2717: x11_fake_data[i] = rand & 0xff;
2718: rand >>= 8;
2719: }
2720: x11_saved_data_len = data_len;
2721: x11_fake_data_len = data_len;
2722:
2723: /* Convert the fake data into hex. */
1.90 markus 2724: len = 2 * data_len + 1;
2725: new_data = xmalloc(len);
1.25 markus 2726: for (i = 0; i < data_len; i++)
1.90 markus 2727: snprintf(new_data + 2 * i, len - 2 * i,
2728: "%02x", (u_char) x11_fake_data[i]);
1.25 markus 2729:
2730: /* Send the request packet. */
1.51 markus 2731: if (compat20) {
2732: channel_request_start(client_session_id, "x11-req", 0);
2733: packet_put_char(0); /* XXX bool single connection */
2734: } else {
2735: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2736: }
2737: packet_put_cstring(proto);
2738: packet_put_cstring(new_data);
1.25 markus 2739: packet_put_int(screen_number);
2740: packet_send();
2741: packet_write_wait();
2742: xfree(new_data);
1.1 deraadt 2743: }
2744:
1.121 markus 2745:
2746: /* -- agent forwarding */
2747:
1.1 deraadt 2748: /* Sends a message to the server to request authentication fd forwarding. */
2749:
1.49 markus 2750: void
1.142 itojun 2751: auth_request_forwarding(void)
1.1 deraadt 2752: {
1.25 markus 2753: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2754: packet_send();
2755: packet_write_wait();
1.1 deraadt 2756: }
2757:
1.27 markus 2758: /*
2759: * Returns the name of the forwarded authentication socket. Returns NULL if
2760: * there is no forwarded authentication socket. The returned value points to
2761: * a static buffer.
2762: */
1.1 deraadt 2763:
1.25 markus 2764: char *
1.142 itojun 2765: auth_get_socket_name(void)
1.1 deraadt 2766: {
1.121 markus 2767: return auth_sock_name;
1.1 deraadt 2768: }
2769:
1.12 markus 2770: /* removes the agent forwarding socket */
2771:
1.49 markus 2772: void
1.123 markus 2773: auth_sock_cleanup_proc(void *_pw)
1.25 markus 2774: {
1.123 markus 2775: struct passwd *pw = _pw;
2776:
1.122 markus 2777: if (auth_sock_name) {
1.123 markus 2778: temporarily_use_uid(pw);
1.122 markus 2779: unlink(auth_sock_name);
2780: rmdir(auth_sock_dir);
2781: auth_sock_name = NULL;
1.123 markus 2782: restore_uid();
1.122 markus 2783: }
1.12 markus 2784: }
2785:
1.27 markus 2786: /*
1.59 markus 2787: * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
1.27 markus 2788: * This starts forwarding authentication requests.
2789: */
1.1 deraadt 2790:
1.59 markus 2791: int
1.25 markus 2792: auth_input_request_forwarding(struct passwd * pw)
1.1 deraadt 2793: {
1.113 markus 2794: Channel *nc;
2795: int sock;
1.25 markus 2796: struct sockaddr_un sunaddr;
2797:
1.121 markus 2798: if (auth_get_socket_name() != NULL) {
2799: error("authentication forwarding requested twice.");
2800: return 0;
2801: }
1.25 markus 2802:
2803: /* Temporarily drop privileged uid for mkdir/bind. */
1.102 markus 2804: temporarily_use_uid(pw);
1.25 markus 2805:
2806: /* Allocate a buffer for the socket name, and format the name. */
1.121 markus 2807: auth_sock_name = xmalloc(MAXPATHLEN);
2808: auth_sock_dir = xmalloc(MAXPATHLEN);
2809: strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1.25 markus 2810:
2811: /* Create private directory for socket */
1.121 markus 2812: if (mkdtemp(auth_sock_dir) == NULL) {
2813: packet_send_debug("Agent forwarding disabled: "
2814: "mkdtemp() failed: %.100s", strerror(errno));
1.59 markus 2815: restore_uid();
1.121 markus 2816: xfree(auth_sock_name);
2817: xfree(auth_sock_dir);
2818: auth_sock_name = NULL;
2819: auth_sock_dir = NULL;
1.59 markus 2820: return 0;
2821: }
1.121 markus 2822: snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d",
2823: auth_sock_dir, (int) getpid());
1.25 markus 2824:
1.122 markus 2825: /* delete agent socket on fatal() */
1.123 markus 2826: fatal_add_cleanup(auth_sock_cleanup_proc, pw);
1.122 markus 2827:
1.25 markus 2828: /* Create the socket. */
2829: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2830: if (sock < 0)
2831: packet_disconnect("socket: %.100s", strerror(errno));
2832:
2833: /* Bind it to the name. */
2834: memset(&sunaddr, 0, sizeof(sunaddr));
2835: sunaddr.sun_family = AF_UNIX;
1.145 stevesk 2836: strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
1.25 markus 2837:
2838: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2839: packet_disconnect("bind: %.100s", strerror(errno));
2840:
2841: /* Restore the privileged uid. */
2842: restore_uid();
2843:
2844: /* Start listening on the socket. */
2845: if (listen(sock, 5) < 0)
2846: packet_disconnect("listen: %.100s", strerror(errno));
2847:
2848: /* Allocate a channel for the authentication agent socket. */
1.113 markus 2849: nc = channel_new("auth socket",
1.73 markus 2850: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2851: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2852: 0, xstrdup("auth socket"), 1);
1.113 markus 2853: if (nc == NULL) {
2854: error("auth_input_request_forwarding: channel_new failed");
1.123 markus 2855: auth_sock_cleanup_proc(pw);
1.124 markus 2856: fatal_remove_cleanup(auth_sock_cleanup_proc, pw);
1.113 markus 2857: close(sock);
2858: return 0;
2859: }
1.121 markus 2860: strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
1.59 markus 2861: return 1;
1.1 deraadt 2862: }
2863:
2864: /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2865:
1.49 markus 2866: void
1.69 markus 2867: auth_input_open_request(int type, int plen, void *ctxt)
1.1 deraadt 2868: {
1.113 markus 2869: Channel *c = NULL;
2870: int remote_id, sock;
1.121 markus 2871: char *name;
1.41 markus 2872:
2873: packet_integrity_check(plen, 4, type);
1.25 markus 2874:
2875: /* Read the remote channel number from the message. */
1.113 markus 2876: remote_id = packet_get_int();
1.25 markus 2877:
1.27 markus 2878: /*
2879: * Get a connection to the local authentication agent (this may again
2880: * get forwarded).
2881: */
1.25 markus 2882: sock = ssh_get_authentication_socket();
2883:
1.27 markus 2884: /*
2885: * If we could not connect the agent, send an error message back to
2886: * the server. This should never happen unless the agent dies,
2887: * because authentication forwarding is only enabled if we have an
2888: * agent.
2889: */
1.113 markus 2890: if (sock >= 0) {
1.121 markus 2891: name = xstrdup("authentication agent connection");
2892: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2893: -1, 0, 0, 0, name, 1);
1.113 markus 2894: if (c == NULL) {
2895: error("auth_input_open_request: channel_new failed");
1.121 markus 2896: xfree(name);
1.113 markus 2897: close(sock);
2898: } else {
2899: c->remote_id = remote_id;
1.133 markus 2900: c->force_drain = 1;
1.113 markus 2901: }
2902: }
2903: if (c == NULL) {
1.25 markus 2904: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2905: packet_put_int(remote_id);
2906: } else {
2907: /* Send a confirmation to the remote host. */
2908: debug("Forwarding authentication connection.");
2909: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2910: packet_put_int(remote_id);
2911: packet_put_int(c->self);
1.25 markus 2912: }
2913: packet_send();
1.1 deraadt 2914: }
![[BACK]](/icons/back.gif){kind=icon}
Return to channels.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh