Annotation of src/usr.bin/ssh/channels.c, Revision 1.152
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"
1.152 ! markus 42: RCSID("$OpenBSD: channels.c,v 1.151 2001/12/27 20:39:58 markus Exp $");
1.1 deraadt 43:
44: #include "ssh.h"
1.82 markus 45: #include "ssh1.h"
46: #include "ssh2.h"
1.1 deraadt 47: #include "packet.h"
48: #include "xmalloc.h"
49: #include "uidswap.h"
1.82 markus 50: #include "log.h"
51: #include "misc.h"
1.14 markus 52: #include "channels.h"
53: #include "compat.h"
1.82 markus 54: #include "canohost.h"
1.64 markus 55: #include "key.h"
56: #include "authfd.h"
1.147 stevesk 57: #include "pathnames.h"
1.44 markus 58:
1.1 deraadt 59:
1.121 markus 60: /* -- channel core */
1.12 markus 61:
1.27 markus 62: /*
63: * Pointer to an array containing all allocated channels. The array is
64: * dynamically extended as needed.
65: */
1.113 markus 66: static Channel **channels = NULL;
1.1 deraadt 67:
1.27 markus 68: /*
69: * Size of the channel array. All slots of the array must always be
1.113 markus 70: * initialized (at least the type field); unused slots set to NULL
1.27 markus 71: */
1.1 deraadt 72: static int channels_alloc = 0;
73:
1.27 markus 74: /*
75: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 76: * updated in channel_new.
1.27 markus 77: */
1.84 markus 78: static int channel_max_fd = 0;
1.1 deraadt 79:
80:
1.121 markus 81: /* -- tcp forwarding */
1.1 deraadt 82:
1.27 markus 83: /*
84: * Data structure for storing which hosts are permitted for forward requests.
85: * The local sides of any remote forwards are stored in this array to prevent
86: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
87: * network (which might be behind a firewall).
88: */
1.25 markus 89: typedef struct {
1.41 markus 90: char *host_to_connect; /* Connect to 'host'. */
91: u_short port_to_connect; /* Connect to 'port'. */
92: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 93: } ForwardPermission;
94:
95: /* List of all permitted host/port pairs to connect. */
96: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 97:
1.1 deraadt 98: /* Number of permitted host/port pairs in the array. */
99: static int num_permitted_opens = 0;
1.27 markus 100: /*
101: * If this is true, all opens are permitted. This is the case on the server
102: * on which we have to trust the client anyway, and the user could do
103: * anything after logging in anyway.
104: */
1.1 deraadt 105: static int all_opens_permitted = 0;
106:
1.121 markus 107:
108: /* -- X11 forwarding */
109:
110: /* Maximum number of fake X11 displays to try. */
111: #define MAX_DISPLAYS 1000
112:
113: /* Saved X11 authentication protocol name. */
114: static char *x11_saved_proto = NULL;
115:
116: /* Saved X11 authentication data. This is the real data. */
117: static char *x11_saved_data = NULL;
118: static u_int x11_saved_data_len = 0;
119:
120: /*
121: * Fake X11 authentication data. This is what the server will be sending us;
122: * we should replace any occurrences of this by the real data.
123: */
124: static char *x11_fake_data = NULL;
125: static u_int x11_fake_data_len;
126:
127:
128: /* -- agent forwarding */
129:
130: #define NUM_SOCKS 10
131:
132: /* Name and directory of socket for authentication agent forwarding. */
133: static char *auth_sock_name = NULL;
134: static char *auth_sock_dir = NULL;
135:
1.82 markus 136: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 137: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 138:
1.121 markus 139: /* helper */
1.127 itojun 140: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 141:
1.121 markus 142: /* -- channel core */
1.41 markus 143:
144: Channel *
145: channel_lookup(int id)
146: {
147: Channel *c;
1.113 markus 148:
1.63 provos 149: if (id < 0 || id > channels_alloc) {
1.41 markus 150: log("channel_lookup: %d: bad id", id);
151: return NULL;
152: }
1.113 markus 153: c = channels[id];
154: if (c == NULL) {
1.41 markus 155: log("channel_lookup: %d: bad id: channel free", id);
156: return NULL;
157: }
158: return c;
1.55 markus 159: }
160:
1.27 markus 161: /*
1.55 markus 162: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 163: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 164: */
1.1 deraadt 165:
1.127 itojun 166: static void
1.71 markus 167: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
168: int extusage, int nonblock)
1.1 deraadt 169: {
1.25 markus 170: /* Update the maximum file descriptor value. */
1.84 markus 171: channel_max_fd = MAX(channel_max_fd, rfd);
172: channel_max_fd = MAX(channel_max_fd, wfd);
173: channel_max_fd = MAX(channel_max_fd, efd);
174:
1.27 markus 175: /* XXX set close-on-exec -markus */
1.55 markus 176:
1.52 markus 177: c->rfd = rfd;
178: c->wfd = wfd;
179: c->sock = (rfd == wfd) ? rfd : -1;
180: c->efd = efd;
181: c->extended_usage = extusage;
1.71 markus 182:
1.91 markus 183: /* XXX ugly hack: nonblock is only set by the server */
184: if (nonblock && isatty(c->rfd)) {
1.94 markus 185: debug("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 186: c->isatty = 1;
187: if (!isatty(c->wfd)) {
1.94 markus 188: error("channel %d: wfd %d is not a tty?",
1.91 markus 189: c->self, c->wfd);
190: }
191: } else {
192: c->isatty = 0;
193: }
194:
1.71 markus 195: /* enable nonblocking mode */
196: if (nonblock) {
197: if (rfd != -1)
198: set_nonblock(rfd);
199: if (wfd != -1)
200: set_nonblock(wfd);
201: if (efd != -1)
202: set_nonblock(efd);
203: }
1.52 markus 204: }
205:
206: /*
207: * Allocate a new channel object and set its type and socket. This will cause
208: * remote_name to be freed.
209: */
210:
1.113 markus 211: Channel *
1.52 markus 212: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.71 markus 213: int window, int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 214: {
215: int i, found;
216: Channel *c;
1.25 markus 217:
218: /* Do initial allocation if this is the first call. */
219: if (channels_alloc == 0) {
1.44 markus 220: chan_init();
1.25 markus 221: channels_alloc = 10;
1.113 markus 222: channels = xmalloc(channels_alloc * sizeof(Channel *));
1.25 markus 223: for (i = 0; i < channels_alloc; i++)
1.113 markus 224: channels[i] = NULL;
1.126 markus 225: fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL);
1.25 markus 226: }
227: /* Try to find a free slot where to put the new channel. */
228: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 229: if (channels[i] == NULL) {
1.25 markus 230: /* Found a free slot. */
231: found = i;
232: break;
233: }
234: if (found == -1) {
1.27 markus 235: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 236: found = channels_alloc;
237: channels_alloc += 10;
1.70 markus 238: debug2("channel: expanding %d", channels_alloc);
1.113 markus 239: channels = xrealloc(channels, channels_alloc * sizeof(Channel *));
1.25 markus 240: for (i = found; i < channels_alloc; i++)
1.113 markus 241: channels[i] = NULL;
1.25 markus 242: }
1.113 markus 243: /* Initialize and return new channel. */
244: c = channels[found] = xmalloc(sizeof(Channel));
1.137 markus 245: memset(c, 0, sizeof(Channel));
1.25 markus 246: buffer_init(&c->input);
247: buffer_init(&c->output);
1.41 markus 248: buffer_init(&c->extended);
1.25 markus 249: chan_init_iostates(c);
1.71 markus 250: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
1.25 markus 251: c->self = found;
252: c->type = type;
1.41 markus 253: c->ctype = ctype;
1.51 markus 254: c->local_window = window;
255: c->local_window_max = window;
256: c->local_consumed = 0;
257: c->local_maxpacket = maxpack;
1.25 markus 258: c->remote_id = -1;
259: c->remote_name = remote_name;
1.41 markus 260: c->remote_window = 0;
261: c->remote_maxpacket = 0;
262: c->cb_fn = NULL;
263: c->cb_arg = NULL;
264: c->cb_event = 0;
1.133 markus 265: c->force_drain = 0;
1.149 markus 266: c->single_connection = 0;
1.131 markus 267: c->detach_user = NULL;
1.65 markus 268: c->input_filter = NULL;
1.25 markus 269: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 270: return c;
1.1 deraadt 271: }
1.52 markus 272:
1.132 markus 273: static int
274: channel_find_maxfd(void)
275: {
276: int i, max = 0;
277: Channel *c;
278:
279: for (i = 0; i < channels_alloc; i++) {
280: c = channels[i];
281: if (c != NULL) {
282: max = MAX(max, c->rfd);
283: max = MAX(max, c->wfd);
284: max = MAX(max, c->efd);
285: }
286: }
287: return max;
288: }
289:
290: int
291: channel_close_fd(int *fdp)
292: {
293: int ret = 0, fd = *fdp;
294:
295: if (fd != -1) {
296: ret = close(fd);
297: *fdp = -1;
298: if (fd == channel_max_fd)
299: channel_max_fd = channel_find_maxfd();
300: }
301: return ret;
302: }
303:
1.52 markus 304: /* Close all channel fd/socket. */
305:
1.127 itojun 306: static void
1.52 markus 307: channel_close_fds(Channel *c)
308: {
1.118 markus 309: debug3("channel_close_fds: channel %d: r %d w %d e %d",
310: c->self, c->rfd, c->wfd, c->efd);
311:
1.132 markus 312: channel_close_fd(&c->sock);
313: channel_close_fd(&c->rfd);
314: channel_close_fd(&c->wfd);
315: channel_close_fd(&c->efd);
1.121 markus 316: }
317:
318: /* Free the channel and close its fd/socket. */
319:
320: void
321: channel_free(Channel *c)
322: {
323: char *s;
324: int i, n;
325:
326: for (n = 0, i = 0; i < channels_alloc; i++)
327: if (channels[i])
328: n++;
329: debug("channel_free: channel %d: %s, nchannels %d", c->self,
330: c->remote_name ? c->remote_name : "???", n);
331:
332: s = channel_open_message();
333: debug3("channel_free: status: %s", s);
334: xfree(s);
335:
336: if (c->sock != -1)
337: shutdown(c->sock, SHUT_RDWR);
338: channel_close_fds(c);
339: buffer_free(&c->input);
340: buffer_free(&c->output);
341: buffer_free(&c->extended);
342: if (c->remote_name) {
343: xfree(c->remote_name);
344: c->remote_name = NULL;
345: }
346: channels[c->self] = NULL;
347: xfree(c);
348: }
349:
350: void
1.126 markus 351: channel_free_all(void)
1.121 markus 352: {
353: int i;
354:
1.126 markus 355: for (i = 0; i < channels_alloc; i++)
356: if (channels[i] != NULL)
357: channel_free(channels[i]);
1.131 markus 358: }
359:
1.121 markus 360: /*
361: * Closes the sockets/fds of all channels. This is used to close extra file
362: * descriptors after a fork.
363: */
364:
365: void
1.142 itojun 366: channel_close_all(void)
1.121 markus 367: {
368: int i;
369:
370: for (i = 0; i < channels_alloc; i++)
371: if (channels[i] != NULL)
372: channel_close_fds(channels[i]);
373: }
374:
375: /*
1.131 markus 376: * Stop listening to channels.
377: */
378:
379: void
380: channel_stop_listening(void)
381: {
382: int i;
383: Channel *c;
384:
385: for (i = 0; i < channels_alloc; i++) {
386: c = channels[i];
387: if (c != NULL) {
388: switch (c->type) {
389: case SSH_CHANNEL_AUTH_SOCKET:
390: case SSH_CHANNEL_PORT_LISTENER:
391: case SSH_CHANNEL_RPORT_LISTENER:
392: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 393: channel_close_fd(&c->sock);
1.131 markus 394: channel_free(c);
395: break;
396: }
397: }
398: }
399: }
400:
401: /*
1.121 markus 402: * Returns true if no channel has too much buffered data, and false if one or
403: * more channel is overfull.
404: */
405:
406: int
1.142 itojun 407: channel_not_very_much_buffered_data(void)
1.121 markus 408: {
409: u_int i;
410: Channel *c;
411:
412: for (i = 0; i < channels_alloc; i++) {
413: c = channels[i];
414: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 415: #if 0
416: if (!compat20 &&
417: buffer_len(&c->input) > packet_get_maxsize()) {
1.121 markus 418: debug("channel %d: big input buffer %d",
419: c->self, buffer_len(&c->input));
420: return 0;
421: }
1.136 markus 422: #endif
1.121 markus 423: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.136 markus 424: debug("channel %d: big output buffer %d > %d",
425: c->self, buffer_len(&c->output),
426: packet_get_maxsize());
1.121 markus 427: return 0;
428: }
429: }
430: }
431: return 1;
432: }
433:
434: /* Returns true if any channel is still open. */
435:
436: int
1.142 itojun 437: channel_still_open(void)
1.121 markus 438: {
439: int i;
440: Channel *c;
441:
442: for (i = 0; i < channels_alloc; i++) {
443: c = channels[i];
444: if (c == NULL)
445: continue;
446: switch (c->type) {
447: case SSH_CHANNEL_X11_LISTENER:
448: case SSH_CHANNEL_PORT_LISTENER:
449: case SSH_CHANNEL_RPORT_LISTENER:
450: case SSH_CHANNEL_CLOSED:
451: case SSH_CHANNEL_AUTH_SOCKET:
452: case SSH_CHANNEL_DYNAMIC:
453: case SSH_CHANNEL_CONNECTING:
454: case SSH_CHANNEL_ZOMBIE:
455: continue;
456: case SSH_CHANNEL_LARVAL:
457: if (!compat20)
458: fatal("cannot happen: SSH_CHANNEL_LARVAL");
459: continue;
460: case SSH_CHANNEL_OPENING:
461: case SSH_CHANNEL_OPEN:
462: case SSH_CHANNEL_X11_OPEN:
463: return 1;
464: case SSH_CHANNEL_INPUT_DRAINING:
465: case SSH_CHANNEL_OUTPUT_DRAINING:
466: if (!compat13)
467: fatal("cannot happen: OUT_DRAIN");
468: return 1;
469: default:
470: fatal("channel_still_open: bad channel type %d", c->type);
471: /* NOTREACHED */
472: }
473: }
474: return 0;
475: }
476:
477: /* Returns the id of an open channel suitable for keepaliving */
478:
479: int
1.142 itojun 480: channel_find_open(void)
1.121 markus 481: {
482: int i;
483: Channel *c;
484:
485: for (i = 0; i < channels_alloc; i++) {
486: c = channels[i];
487: if (c == NULL)
488: continue;
489: switch (c->type) {
490: case SSH_CHANNEL_CLOSED:
491: case SSH_CHANNEL_DYNAMIC:
492: case SSH_CHANNEL_X11_LISTENER:
493: case SSH_CHANNEL_PORT_LISTENER:
494: case SSH_CHANNEL_RPORT_LISTENER:
495: case SSH_CHANNEL_OPENING:
496: case SSH_CHANNEL_CONNECTING:
497: case SSH_CHANNEL_ZOMBIE:
498: continue;
499: case SSH_CHANNEL_LARVAL:
500: case SSH_CHANNEL_AUTH_SOCKET:
501: case SSH_CHANNEL_OPEN:
502: case SSH_CHANNEL_X11_OPEN:
503: return i;
504: case SSH_CHANNEL_INPUT_DRAINING:
505: case SSH_CHANNEL_OUTPUT_DRAINING:
506: if (!compat13)
507: fatal("cannot happen: OUT_DRAIN");
508: return i;
509: default:
510: fatal("channel_find_open: bad channel type %d", c->type);
511: /* NOTREACHED */
512: }
513: }
514: return -1;
515: }
516:
517:
518: /*
519: * Returns a message describing the currently open forwarded connections,
520: * suitable for sending to the client. The message contains crlf pairs for
521: * newlines.
522: */
523:
524: char *
1.142 itojun 525: channel_open_message(void)
1.121 markus 526: {
527: Buffer buffer;
528: Channel *c;
529: char buf[1024], *cp;
530: int i;
531:
532: buffer_init(&buffer);
533: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
534: buffer_append(&buffer, buf, strlen(buf));
535: for (i = 0; i < channels_alloc; i++) {
536: c = channels[i];
537: if (c == NULL)
538: continue;
539: switch (c->type) {
540: case SSH_CHANNEL_X11_LISTENER:
541: case SSH_CHANNEL_PORT_LISTENER:
542: case SSH_CHANNEL_RPORT_LISTENER:
543: case SSH_CHANNEL_CLOSED:
544: case SSH_CHANNEL_AUTH_SOCKET:
545: case SSH_CHANNEL_ZOMBIE:
546: continue;
547: case SSH_CHANNEL_LARVAL:
548: case SSH_CHANNEL_OPENING:
549: case SSH_CHANNEL_CONNECTING:
550: case SSH_CHANNEL_DYNAMIC:
551: case SSH_CHANNEL_OPEN:
552: case SSH_CHANNEL_X11_OPEN:
553: case SSH_CHANNEL_INPUT_DRAINING:
554: case SSH_CHANNEL_OUTPUT_DRAINING:
555: snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
556: c->self, c->remote_name,
557: c->type, c->remote_id,
558: c->istate, buffer_len(&c->input),
559: c->ostate, buffer_len(&c->output),
560: c->rfd, c->wfd);
561: buffer_append(&buffer, buf, strlen(buf));
562: continue;
563: default:
564: fatal("channel_open_message: bad channel type %d", c->type);
565: /* NOTREACHED */
566: }
567: }
568: buffer_append(&buffer, "\0", 1);
569: cp = xstrdup(buffer_ptr(&buffer));
570: buffer_free(&buffer);
571: return cp;
572: }
573:
574: void
575: channel_send_open(int id)
576: {
577: Channel *c = channel_lookup(id);
578: if (c == NULL) {
579: log("channel_send_open: %d: bad id", id);
580: return;
581: }
582: debug("send channel open %d", id);
583: packet_start(SSH2_MSG_CHANNEL_OPEN);
584: packet_put_cstring(c->ctype);
585: packet_put_int(c->self);
586: packet_put_int(c->local_window);
587: packet_put_int(c->local_maxpacket);
588: packet_send();
589: }
590:
591: void
592: channel_request(int id, char *service, int wantconfirm)
593: {
594: channel_request_start(id, service, wantconfirm);
595: packet_send();
596: debug("channel request %d: %s", id, service) ;
597: }
598: void
599: channel_request_start(int id, char *service, int wantconfirm)
600: {
601: Channel *c = channel_lookup(id);
602: if (c == NULL) {
603: log("channel_request: %d: bad id", id);
604: return;
605: }
606: packet_start(SSH2_MSG_CHANNEL_REQUEST);
607: packet_put_int(c->remote_id);
608: packet_put_cstring(service);
609: packet_put_char(wantconfirm);
610: }
611: void
612: channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
613: {
614: Channel *c = channel_lookup(id);
615: if (c == NULL) {
616: log("channel_register_callback: %d: bad id", id);
617: return;
618: }
619: c->cb_event = mtype;
620: c->cb_fn = fn;
621: c->cb_arg = arg;
622: }
623: void
624: channel_register_cleanup(int id, channel_callback_fn *fn)
625: {
626: Channel *c = channel_lookup(id);
627: if (c == NULL) {
628: log("channel_register_cleanup: %d: bad id", id);
629: return;
630: }
1.131 markus 631: c->detach_user = fn;
1.121 markus 632: }
633: void
634: channel_cancel_cleanup(int id)
635: {
636: Channel *c = channel_lookup(id);
637: if (c == NULL) {
638: log("channel_cancel_cleanup: %d: bad id", id);
639: return;
1.52 markus 640: }
1.131 markus 641: c->detach_user = NULL;
1.121 markus 642: }
643: void
644: channel_register_filter(int id, channel_filter_fn *fn)
645: {
646: Channel *c = channel_lookup(id);
647: if (c == NULL) {
648: log("channel_register_filter: %d: bad id", id);
649: return;
1.52 markus 650: }
1.121 markus 651: c->input_filter = fn;
1.52 markus 652: }
653:
1.49 markus 654: void
1.121 markus 655: channel_set_fds(int id, int rfd, int wfd, int efd,
656: int extusage, int nonblock)
1.1 deraadt 657: {
1.121 markus 658: Channel *c = channel_lookup(id);
659: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
660: fatal("channel_activate for non-larval channel %d.", id);
661: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
662: c->type = SSH_CHANNEL_OPEN;
663: /* XXX window size? */
664: c->local_window = c->local_window_max = c->local_maxpacket * 2;
665: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
666: packet_put_int(c->remote_id);
667: packet_put_int(c->local_window);
668: packet_send();
1.1 deraadt 669: }
670:
1.27 markus 671: /*
1.41 markus 672: * 'channel_pre*' are called just before select() to add any bits relevant to
673: * channels in the select bitmasks.
674: */
675: /*
676: * 'channel_post*': perform any appropriate operations for channels which
677: * have events pending.
1.27 markus 678: */
1.41 markus 679: typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
680: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
681: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
682:
1.127 itojun 683: static void
1.41 markus 684: channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
685: {
686: FD_SET(c->sock, readset);
687: }
688:
1.127 itojun 689: static void
1.75 markus 690: channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
691: {
692: debug3("channel %d: waiting for connection", c->self);
693: FD_SET(c->sock, writeset);
694: }
695:
1.127 itojun 696: static void
1.41 markus 697: channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
698: {
699: if (buffer_len(&c->input) < packet_get_maxsize())
700: FD_SET(c->sock, readset);
701: if (buffer_len(&c->output) > 0)
702: FD_SET(c->sock, writeset);
703: }
1.1 deraadt 704:
1.127 itojun 705: static void
1.41 markus 706: channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
707: {
708: /* test whether sockets are 'alive' for read/write */
709: if (c->istate == CHAN_INPUT_OPEN)
710: if (buffer_len(&c->input) < packet_get_maxsize())
711: FD_SET(c->sock, readset);
712: if (c->ostate == CHAN_OUTPUT_OPEN ||
713: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
714: if (buffer_len(&c->output) > 0) {
715: FD_SET(c->sock, writeset);
716: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
717: chan_obuf_empty(c);
718: }
719: }
720: }
721:
1.127 itojun 722: static void
1.44 markus 723: channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset)
724: {
725: if (c->istate == CHAN_INPUT_OPEN &&
726: c->remote_window > 0 &&
727: buffer_len(&c->input) < c->remote_window)
728: FD_SET(c->rfd, readset);
729: if (c->ostate == CHAN_OUTPUT_OPEN ||
730: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
731: if (buffer_len(&c->output) > 0) {
732: FD_SET(c->wfd, writeset);
733: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
734: chan_obuf_empty(c);
735: }
736: }
737: /** XXX check close conditions, too */
738: if (c->efd != -1) {
739: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
740: buffer_len(&c->extended) > 0)
741: FD_SET(c->efd, writeset);
742: else if (c->extended_usage == CHAN_EXTENDED_READ &&
743: buffer_len(&c->extended) < c->remote_window)
744: FD_SET(c->efd, readset);
745: }
746: }
747:
1.127 itojun 748: static void
1.41 markus 749: channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
750: {
751: if (buffer_len(&c->input) == 0) {
752: packet_start(SSH_MSG_CHANNEL_CLOSE);
753: packet_put_int(c->remote_id);
754: packet_send();
755: c->type = SSH_CHANNEL_CLOSED;
1.105 markus 756: debug("channel %d: closing after input drain.", c->self);
1.41 markus 757: }
758: }
759:
1.127 itojun 760: static void
1.41 markus 761: channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
762: {
763: if (buffer_len(&c->output) == 0)
1.113 markus 764: chan_mark_dead(c);
1.49 markus 765: else
1.41 markus 766: FD_SET(c->sock, writeset);
767: }
768:
769: /*
770: * This is a special state for X11 authentication spoofing. An opened X11
771: * connection (when authentication spoofing is being done) remains in this
772: * state until the first packet has been completely read. The authentication
773: * data in that packet is then substituted by the real data if it matches the
774: * fake data, and the channel is put into normal mode.
1.51 markus 775: * XXX All this happens at the client side.
1.121 markus 776: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 777: */
1.127 itojun 778: static int
1.121 markus 779: x11_open_helper(Buffer *b)
1.1 deraadt 780: {
1.77 markus 781: u_char *ucp;
782: u_int proto_len, data_len;
1.25 markus 783:
1.41 markus 784: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 785: if (buffer_len(b) < 12)
1.41 markus 786: return 0;
787:
788: /* Parse the lengths of variable-length fields. */
1.121 markus 789: ucp = (u_char *) buffer_ptr(b);
1.41 markus 790: if (ucp[0] == 0x42) { /* Byte order MSB first. */
791: proto_len = 256 * ucp[6] + ucp[7];
792: data_len = 256 * ucp[8] + ucp[9];
793: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
794: proto_len = ucp[6] + 256 * ucp[7];
795: data_len = ucp[8] + 256 * ucp[9];
796: } else {
797: debug("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 798: ucp[0]);
1.41 markus 799: return -1;
800: }
801:
802: /* Check if the whole packet is in buffer. */
1.121 markus 803: if (buffer_len(b) <
1.41 markus 804: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
805: return 0;
806:
807: /* Check if authentication protocol matches. */
808: if (proto_len != strlen(x11_saved_proto) ||
809: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
810: debug("X11 connection uses different authentication protocol.");
811: return -1;
812: }
813: /* Check if authentication data matches our fake data. */
814: if (data_len != x11_fake_data_len ||
815: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
816: x11_fake_data, x11_fake_data_len) != 0) {
817: debug("X11 auth data does not match fake data.");
818: return -1;
819: }
820: /* Check fake data length */
821: if (x11_fake_data_len != x11_saved_data_len) {
822: error("X11 fake_data_len %d != saved_data_len %d",
823: x11_fake_data_len, x11_saved_data_len);
824: return -1;
825: }
826: /*
827: * Received authentication protocol and data match
828: * our fake data. Substitute the fake data with real
829: * data.
830: */
831: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
832: x11_saved_data, x11_saved_data_len);
833: return 1;
834: }
835:
1.127 itojun 836: static void
1.41 markus 837: channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
838: {
1.121 markus 839: int ret = x11_open_helper(&c->output);
1.41 markus 840: if (ret == 1) {
841: /* Start normal processing for the channel. */
842: c->type = SSH_CHANNEL_OPEN;
1.47 markus 843: channel_pre_open_13(c, readset, writeset);
1.41 markus 844: } else if (ret == -1) {
845: /*
846: * We have received an X11 connection that has bad
847: * authentication information.
848: */
1.98 millert 849: log("X11 connection rejected because of wrong authentication.");
1.41 markus 850: buffer_clear(&c->input);
851: buffer_clear(&c->output);
1.132 markus 852: channel_close_fd(&c->sock);
1.41 markus 853: c->sock = -1;
854: c->type = SSH_CHANNEL_CLOSED;
855: packet_start(SSH_MSG_CHANNEL_CLOSE);
856: packet_put_int(c->remote_id);
857: packet_send();
858: }
859: }
1.25 markus 860:
1.127 itojun 861: static void
1.51 markus 862: channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
1.41 markus 863: {
1.121 markus 864: int ret = x11_open_helper(&c->output);
1.133 markus 865:
866: /* c->force_drain = 1; */
867:
1.41 markus 868: if (ret == 1) {
869: c->type = SSH_CHANNEL_OPEN;
1.57 markus 870: if (compat20)
871: channel_pre_open_20(c, readset, writeset);
872: else
873: channel_pre_open_15(c, readset, writeset);
1.41 markus 874: } else if (ret == -1) {
875: debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.51 markus 876: chan_read_failed(c); /** force close? */
1.41 markus 877: chan_write_failed(c);
878: debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
879: }
880: }
1.25 markus 881:
1.104 markus 882: /* try to decode a socks4 header */
1.127 itojun 883: static int
1.104 markus 884: channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
1.103 markus 885: {
886: u_char *p, *host;
1.109 markus 887: int len, have, i, found;
1.148 deraadt 888: char username[256];
1.103 markus 889: struct {
890: u_int8_t version;
891: u_int8_t command;
892: u_int16_t dest_port;
1.104 markus 893: struct in_addr dest_addr;
1.103 markus 894: } s4_req, s4_rsp;
895:
1.104 markus 896: debug2("channel %d: decode socks4", c->self);
1.109 markus 897:
898: have = buffer_len(&c->input);
899: len = sizeof(s4_req);
900: if (have < len)
901: return 0;
902: p = buffer_ptr(&c->input);
903: for (found = 0, i = len; i < have; i++) {
904: if (p[i] == '\0') {
905: found = 1;
906: break;
907: }
908: if (i > 1024) {
909: /* the peer is probably sending garbage */
910: debug("channel %d: decode socks4: too long",
911: c->self);
912: return -1;
913: }
914: }
915: if (!found)
916: return 0;
1.103 markus 917: buffer_get(&c->input, (char *)&s4_req.version, 1);
918: buffer_get(&c->input, (char *)&s4_req.command, 1);
919: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 920: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 921: have = buffer_len(&c->input);
1.103 markus 922: p = buffer_ptr(&c->input);
923: len = strlen(p);
1.106 markus 924: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 925: if (len > have)
1.104 markus 926: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 927: c->self, len, have);
928: strlcpy(username, p, sizeof(username));
929: buffer_consume(&c->input, len);
930: buffer_consume(&c->input, 1); /* trailing '\0' */
931:
1.104 markus 932: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 933: strlcpy(c->path, host, sizeof(c->path));
934: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 935:
1.106 markus 936: debug("channel %d: dynamic request: socks4 host %s port %u command %u",
937: c->self, host, c->host_port, s4_req.command);
1.103 markus 938:
1.104 markus 939: if (s4_req.command != 1) {
940: debug("channel %d: cannot handle: socks4 cn %d",
941: c->self, s4_req.command);
942: return -1;
1.103 markus 943: }
1.104 markus 944: s4_rsp.version = 0; /* vn: 0 for reply */
945: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 946: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 947: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.103 markus 948: buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
1.104 markus 949: return 1;
950: }
951:
952: /* dynamic port forwarding */
1.127 itojun 953: static void
1.104 markus 954: channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
955: {
956: u_char *p;
957: int have, ret;
1.103 markus 958:
1.104 markus 959: have = buffer_len(&c->input);
1.137 markus 960: c->delayed = 0;
1.104 markus 961: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 962: /* buffer_dump(&c->input); */
1.104 markus 963: /* check if the fixed size part of the packet is in buffer. */
964: if (have < 4) {
965: /* need more */
966: FD_SET(c->sock, readset);
967: return;
968: }
969: /* try to guess the protocol */
970: p = buffer_ptr(&c->input);
971: switch (p[0]) {
972: case 0x04:
973: ret = channel_decode_socks4(c, readset, writeset);
974: break;
975: default:
976: ret = -1;
977: break;
978: }
979: if (ret < 0) {
1.113 markus 980: chan_mark_dead(c);
1.104 markus 981: } else if (ret == 0) {
982: debug2("channel %d: pre_dynamic: need more", c->self);
983: /* need more */
984: FD_SET(c->sock, readset);
985: } else {
986: /* switch to the next state */
987: c->type = SSH_CHANNEL_OPENING;
988: port_open_helper(c, "direct-tcpip");
989: }
1.103 markus 990: }
991:
1.41 markus 992: /* This is our fake X11 server socket. */
1.127 itojun 993: static void
1.41 markus 994: channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
995: {
1.113 markus 996: Channel *nc;
1.41 markus 997: struct sockaddr addr;
1.146 stevesk 998: int newsock, on = 1;
1.41 markus 999: socklen_t addrlen;
1.85 markus 1000: char buf[16384], *remote_ipaddr;
1.51 markus 1001: int remote_port;
1.25 markus 1002:
1.41 markus 1003: if (FD_ISSET(c->sock, readset)) {
1004: debug("X11 connection requested.");
1005: addrlen = sizeof(addr);
1006: newsock = accept(c->sock, &addr, &addrlen);
1.149 markus 1007: if (c->single_connection) {
1008: debug("single_connection: closing X11 listener.");
1009: channel_close_fd(&c->sock);
1010: chan_mark_dead(c);
1011: }
1.41 markus 1012: if (newsock < 0) {
1013: error("accept: %.100s", strerror(errno));
1014: return;
1015: }
1.146 stevesk 1016: if (setsockopt(newsock, IPPROTO_TCP, TCP_NODELAY, &on,
1017: sizeof on) == -1)
1018: error("setsockopt TCP_NODELAY: %.100s",
1019: strerror(errno));
1.85 markus 1020: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1021: remote_port = get_peer_port(newsock);
1.41 markus 1022: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1023: remote_ipaddr, remote_port);
1.51 markus 1024:
1.113 markus 1025: nc = channel_new("accepted x11 socket",
1.51 markus 1026: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1027: c->local_window_max, c->local_maxpacket,
1.71 markus 1028: 0, xstrdup(buf), 1);
1.113 markus 1029: if (nc == NULL) {
1030: close(newsock);
1031: xfree(remote_ipaddr);
1032: return;
1033: }
1.51 markus 1034: if (compat20) {
1035: packet_start(SSH2_MSG_CHANNEL_OPEN);
1036: packet_put_cstring("x11");
1.113 markus 1037: packet_put_int(nc->self);
1.149 markus 1038: packet_put_int(nc->local_window_max);
1039: packet_put_int(nc->local_maxpacket);
1.85 markus 1040: /* originator ipaddr and port */
1041: packet_put_cstring(remote_ipaddr);
1.57 markus 1042: if (datafellows & SSH_BUG_X11FWD) {
1043: debug("ssh2 x11 bug compat mode");
1044: } else {
1045: packet_put_int(remote_port);
1046: }
1.51 markus 1047: packet_send();
1048: } else {
1049: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1050: packet_put_int(nc->self);
1.121 markus 1051: if (packet_get_protocol_flags() &
1052: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1053: packet_put_cstring(buf);
1.51 markus 1054: packet_send();
1055: }
1.85 markus 1056: xfree(remote_ipaddr);
1.41 markus 1057: }
1058: }
1.25 markus 1059:
1.127 itojun 1060: static void
1.103 markus 1061: port_open_helper(Channel *c, char *rtype)
1062: {
1063: int direct;
1064: char buf[1024];
1065: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1066: u_short remote_port = get_peer_port(c->sock);
1067:
1068: direct = (strcmp(rtype, "direct-tcpip") == 0);
1069:
1070: snprintf(buf, sizeof buf,
1071: "%s: listening port %d for %.100s port %d, "
1072: "connect from %.200s port %d",
1073: rtype, c->listening_port, c->path, c->host_port,
1074: remote_ipaddr, remote_port);
1075:
1076: xfree(c->remote_name);
1077: c->remote_name = xstrdup(buf);
1078:
1079: if (compat20) {
1080: packet_start(SSH2_MSG_CHANNEL_OPEN);
1081: packet_put_cstring(rtype);
1082: packet_put_int(c->self);
1083: packet_put_int(c->local_window_max);
1084: packet_put_int(c->local_maxpacket);
1085: if (direct) {
1086: /* target host, port */
1087: packet_put_cstring(c->path);
1088: packet_put_int(c->host_port);
1089: } else {
1090: /* listen address, port */
1091: packet_put_cstring(c->path);
1092: packet_put_int(c->listening_port);
1093: }
1094: /* originator host and port */
1095: packet_put_cstring(remote_ipaddr);
1096: packet_put_int(remote_port);
1097: packet_send();
1098: } else {
1099: packet_start(SSH_MSG_PORT_OPEN);
1100: packet_put_int(c->self);
1101: packet_put_cstring(c->path);
1102: packet_put_int(c->host_port);
1.121 markus 1103: if (packet_get_protocol_flags() &
1104: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1105: packet_put_cstring(c->remote_name);
1106: packet_send();
1107: }
1108: xfree(remote_ipaddr);
1109: }
1110:
1.41 markus 1111: /*
1112: * This socket is listening for connections to a forwarded TCP/IP port.
1113: */
1.127 itojun 1114: static void
1.41 markus 1115: channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
1116: {
1.103 markus 1117: Channel *nc;
1.41 markus 1118: struct sockaddr addr;
1.113 markus 1119: int newsock, nextstate;
1.41 markus 1120: socklen_t addrlen;
1.103 markus 1121: char *rtype;
1.73 markus 1122:
1.41 markus 1123: if (FD_ISSET(c->sock, readset)) {
1124: debug("Connection to port %d forwarding "
1125: "to %.100s port %d requested.",
1126: c->listening_port, c->path, c->host_port);
1.103 markus 1127:
1.137 markus 1128: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1129: nextstate = SSH_CHANNEL_OPENING;
1130: rtype = "forwarded-tcpip";
1131: } else {
1132: if (c->host_port == 0) {
1133: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1134: rtype = "dynamic-tcpip";
1.137 markus 1135: } else {
1136: nextstate = SSH_CHANNEL_OPENING;
1137: rtype = "direct-tcpip";
1138: }
1139: }
1.103 markus 1140:
1.41 markus 1141: addrlen = sizeof(addr);
1142: newsock = accept(c->sock, &addr, &addrlen);
1143: if (newsock < 0) {
1144: error("accept: %.100s", strerror(errno));
1145: return;
1146: }
1.113 markus 1147: nc = channel_new(rtype,
1.103 markus 1148: nextstate, newsock, newsock, -1,
1.41 markus 1149: c->local_window_max, c->local_maxpacket,
1.103 markus 1150: 0, xstrdup(rtype), 1);
1151: if (nc == NULL) {
1.113 markus 1152: error("channel_post_port_listener: no new channel:");
1153: close(newsock);
1.103 markus 1154: return;
1.41 markus 1155: }
1.103 markus 1156: nc->listening_port = c->listening_port;
1157: nc->host_port = c->host_port;
1158: strlcpy(nc->path, c->path, sizeof(nc->path));
1159:
1.137 markus 1160: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1161: /*
1162: * do not call the channel_post handler until
1163: * this flag has been reset by a pre-handler.
1164: * otherwise the FD_ISSET calls might overflow
1165: */
1166: nc->delayed = 1;
1167: } else {
1.103 markus 1168: port_open_helper(nc, rtype);
1.137 markus 1169: }
1.41 markus 1170: }
1171: }
1.25 markus 1172:
1.41 markus 1173: /*
1174: * This is the authentication agent socket listening for connections from
1175: * clients.
1176: */
1.127 itojun 1177: static void
1.41 markus 1178: channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
1179: {
1.113 markus 1180: Channel *nc;
1.121 markus 1181: char *name;
1.113 markus 1182: int newsock;
1.41 markus 1183: struct sockaddr addr;
1184: socklen_t addrlen;
1.25 markus 1185:
1.41 markus 1186: if (FD_ISSET(c->sock, readset)) {
1187: addrlen = sizeof(addr);
1188: newsock = accept(c->sock, &addr, &addrlen);
1189: if (newsock < 0) {
1190: error("accept from auth socket: %.100s", strerror(errno));
1191: return;
1192: }
1.121 markus 1193: name = xstrdup("accepted auth socket");
1.113 markus 1194: nc = channel_new("accepted auth socket",
1.73 markus 1195: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1196: c->local_window_max, c->local_maxpacket,
1.121 markus 1197: 0, name, 1);
1.113 markus 1198: if (nc == NULL) {
1199: error("channel_post_auth_listener: channel_new failed");
1.121 markus 1200: xfree(name);
1.113 markus 1201: close(newsock);
1202: }
1.73 markus 1203: if (compat20) {
1204: packet_start(SSH2_MSG_CHANNEL_OPEN);
1205: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1206: packet_put_int(nc->self);
1.73 markus 1207: packet_put_int(c->local_window_max);
1208: packet_put_int(c->local_maxpacket);
1209: } else {
1210: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1211: packet_put_int(nc->self);
1.73 markus 1212: }
1.41 markus 1213: packet_send();
1214: }
1215: }
1.25 markus 1216:
1.127 itojun 1217: static void
1.75 markus 1218: channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
1219: {
1.114 markus 1220: int err = 0;
1.129 stevesk 1221: socklen_t sz = sizeof(err);
1.114 markus 1222:
1.75 markus 1223: if (FD_ISSET(c->sock, writeset)) {
1.114 markus 1224: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
1225: &sz) < 0) {
1226: err = errno;
1227: error("getsockopt SO_ERROR failed");
1228: }
1229: if (err == 0) {
1230: debug("channel %d: connected", c->self);
1231: c->type = SSH_CHANNEL_OPEN;
1232: if (compat20) {
1233: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1234: packet_put_int(c->remote_id);
1235: packet_put_int(c->self);
1236: packet_put_int(c->local_window);
1237: packet_put_int(c->local_maxpacket);
1238: } else {
1239: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1240: packet_put_int(c->remote_id);
1241: packet_put_int(c->self);
1242: }
1.75 markus 1243: } else {
1.114 markus 1244: debug("channel %d: not connected: %s",
1245: c->self, strerror(err));
1246: if (compat20) {
1247: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1248: packet_put_int(c->remote_id);
1249: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1250: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1251: packet_put_cstring(strerror(err));
1252: packet_put_cstring("");
1253: }
1.75 markus 1254: } else {
1.114 markus 1255: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1256: packet_put_int(c->remote_id);
1.75 markus 1257: }
1.114 markus 1258: chan_mark_dead(c);
1.75 markus 1259: }
1.114 markus 1260: packet_send();
1.75 markus 1261: }
1262: }
1263:
1.127 itojun 1264: static int
1.41 markus 1265: channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
1266: {
1267: char buf[16*1024];
1268: int len;
1.25 markus 1269:
1.118 markus 1270: if (c->rfd != -1 &&
1.41 markus 1271: FD_ISSET(c->rfd, readset)) {
1272: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1273: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1274: return 1;
1.41 markus 1275: if (len <= 0) {
1.51 markus 1276: debug("channel %d: read<=0 rfd %d len %d",
1.41 markus 1277: c->self, c->rfd, len);
1.104 markus 1278: if (c->type != SSH_CHANNEL_OPEN) {
1279: debug("channel %d: not open", c->self);
1.113 markus 1280: chan_mark_dead(c);
1.103 markus 1281: return -1;
1.104 markus 1282: } else if (compat13) {
1.41 markus 1283: buffer_consume(&c->output, buffer_len(&c->output));
1284: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.121 markus 1285: debug("channel %d: input draining.", c->self);
1.25 markus 1286: } else {
1.41 markus 1287: chan_read_failed(c);
1.25 markus 1288: }
1.41 markus 1289: return -1;
1290: }
1.143 deraadt 1291: if (c->input_filter != NULL) {
1.66 markus 1292: if (c->input_filter(c, buf, len) == -1) {
1.105 markus 1293: debug("channel %d: filter stops", c->self);
1.65 markus 1294: chan_read_failed(c);
1295: }
1296: } else {
1297: buffer_append(&c->input, buf, len);
1298: }
1.41 markus 1299: }
1300: return 1;
1301: }
1.127 itojun 1302: static int
1.41 markus 1303: channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
1304: {
1.95 markus 1305: struct termios tio;
1.134 markus 1306: u_char *data;
1307: u_int dlen;
1.41 markus 1308: int len;
1.25 markus 1309:
1.41 markus 1310: /* Send buffered output data to the socket. */
1.118 markus 1311: if (c->wfd != -1 &&
1.41 markus 1312: FD_ISSET(c->wfd, writeset) &&
1313: buffer_len(&c->output) > 0) {
1.134 markus 1314: data = buffer_ptr(&c->output);
1315: dlen = buffer_len(&c->output);
1316: len = write(c->wfd, data, dlen);
1.53 markus 1317: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1318: return 1;
1.41 markus 1319: if (len <= 0) {
1.104 markus 1320: if (c->type != SSH_CHANNEL_OPEN) {
1321: debug("channel %d: not open", c->self);
1.113 markus 1322: chan_mark_dead(c);
1.104 markus 1323: return -1;
1324: } else if (compat13) {
1.41 markus 1325: buffer_consume(&c->output, buffer_len(&c->output));
1.121 markus 1326: debug("channel %d: input draining.", c->self);
1.41 markus 1327: c->type = SSH_CHANNEL_INPUT_DRAINING;
1328: } else {
1329: chan_write_failed(c);
1330: }
1331: return -1;
1.91 markus 1332: }
1.134 markus 1333: if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
1.91 markus 1334: if (tcgetattr(c->wfd, &tio) == 0 &&
1335: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1336: /*
1337: * Simulate echo to reduce the impact of
1.96 markus 1338: * traffic analysis. We need to match the
1.95 markus 1339: * size of a SSH2_MSG_CHANNEL_DATA message
1340: * (4 byte channel id + data)
1.91 markus 1341: */
1.95 markus 1342: packet_send_ignore(4 + len);
1.91 markus 1343: packet_send();
1344: }
1.25 markus 1345: }
1.41 markus 1346: buffer_consume(&c->output, len);
1.44 markus 1347: if (compat20 && len > 0) {
1348: c->local_consumed += len;
1349: }
1350: }
1351: return 1;
1352: }
1.127 itojun 1353: static int
1.44 markus 1354: channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
1355: {
1356: char buf[16*1024];
1357: int len;
1358:
1.45 markus 1359: /** XXX handle drain efd, too */
1.44 markus 1360: if (c->efd != -1) {
1361: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1362: FD_ISSET(c->efd, writeset) &&
1363: buffer_len(&c->extended) > 0) {
1364: len = write(c->efd, buffer_ptr(&c->extended),
1365: buffer_len(&c->extended));
1.70 markus 1366: debug2("channel %d: written %d to efd %d",
1.44 markus 1367: c->self, len, c->efd);
1.93 markus 1368: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1369: return 1;
1370: if (len <= 0) {
1371: debug2("channel %d: closing write-efd %d",
1372: c->self, c->efd);
1.132 markus 1373: channel_close_fd(&c->efd);
1.93 markus 1374: } else {
1.44 markus 1375: buffer_consume(&c->extended, len);
1376: c->local_consumed += len;
1377: }
1378: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1379: FD_ISSET(c->efd, readset)) {
1380: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1381: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1382: c->self, len, c->efd);
1.93 markus 1383: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1384: return 1;
1385: if (len <= 0) {
1386: debug2("channel %d: closing read-efd %d",
1.45 markus 1387: c->self, c->efd);
1.132 markus 1388: channel_close_fd(&c->efd);
1.93 markus 1389: } else {
1.44 markus 1390: buffer_append(&c->extended, buf, len);
1.93 markus 1391: }
1.44 markus 1392: }
1393: }
1394: return 1;
1395: }
1.127 itojun 1396: static int
1.93 markus 1397: channel_check_window(Channel *c)
1.44 markus 1398: {
1.104 markus 1399: if (c->type == SSH_CHANNEL_OPEN &&
1400: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.44 markus 1401: c->local_window < c->local_window_max/2 &&
1402: c->local_consumed > 0) {
1403: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1404: packet_put_int(c->remote_id);
1405: packet_put_int(c->local_consumed);
1406: packet_send();
1.70 markus 1407: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1408: c->self, c->local_window,
1409: c->local_consumed);
1410: c->local_window += c->local_consumed;
1411: c->local_consumed = 0;
1.1 deraadt 1412: }
1.41 markus 1413: return 1;
1.1 deraadt 1414: }
1415:
1.127 itojun 1416: static void
1.41 markus 1417: channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
1418: {
1.137 markus 1419: if (c->delayed)
1420: return;
1.41 markus 1421: channel_handle_rfd(c, readset, writeset);
1422: channel_handle_wfd(c, readset, writeset);
1423: }
1.1 deraadt 1424:
1.127 itojun 1425: static void
1.44 markus 1426: channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset)
1427: {
1.137 markus 1428: if (c->delayed)
1429: return;
1.44 markus 1430: channel_handle_rfd(c, readset, writeset);
1431: channel_handle_wfd(c, readset, writeset);
1432: channel_handle_efd(c, readset, writeset);
1.93 markus 1433:
1434: channel_check_window(c);
1.44 markus 1435: }
1436:
1.127 itojun 1437: static void
1.41 markus 1438: channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
1.1 deraadt 1439: {
1.41 markus 1440: int len;
1441: /* Send buffered output data to the socket. */
1442: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1443: len = write(c->sock, buffer_ptr(&c->output),
1444: buffer_len(&c->output));
1445: if (len <= 0)
1446: buffer_consume(&c->output, buffer_len(&c->output));
1447: else
1448: buffer_consume(&c->output, len);
1449: }
1450: }
1.25 markus 1451:
1.127 itojun 1452: static void
1.44 markus 1453: channel_handler_init_20(void)
1454: {
1455: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
1.51 markus 1456: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1457: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1458: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1459: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1460: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1461: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1462: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1463:
1464: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
1465: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1466: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1467: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1468: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1469: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1470: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2;
1.44 markus 1471: }
1472:
1.127 itojun 1473: static void
1.41 markus 1474: channel_handler_init_13(void)
1475: {
1476: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1477: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1478: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1479: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1480: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1481: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1482: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1483: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1484: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1485:
1.41 markus 1486: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1487: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1488: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1489: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1490: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1491: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1492: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
1.41 markus 1493: }
1.25 markus 1494:
1.127 itojun 1495: static void
1.41 markus 1496: channel_handler_init_15(void)
1497: {
1498: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
1.51 markus 1499: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1500: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1501: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1502: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1503: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1504: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1505:
1.41 markus 1506: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1507: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1508: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1509: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
1.75 markus 1510: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.104 markus 1511: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
1.41 markus 1512: }
1.27 markus 1513:
1.127 itojun 1514: static void
1.41 markus 1515: channel_handler_init(void)
1516: {
1517: int i;
1.148 deraadt 1518: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1519: channel_pre[i] = NULL;
1520: channel_post[i] = NULL;
1521: }
1.44 markus 1522: if (compat20)
1523: channel_handler_init_20();
1524: else if (compat13)
1.41 markus 1525: channel_handler_init_13();
1526: else
1527: channel_handler_init_15();
1528: }
1.25 markus 1529:
1.140 markus 1530: /* gc dead channels */
1531: static void
1532: channel_garbage_collect(Channel *c)
1533: {
1534: if (c == NULL)
1535: return;
1536: if (c->detach_user != NULL) {
1537: if (!chan_is_dead(c, 0))
1538: return;
1539: debug("channel %d: gc: notify user", c->self);
1540: c->detach_user(c->self, NULL);
1541: /* if we still have a callback */
1542: if (c->detach_user != NULL)
1543: return;
1544: debug("channel %d: gc: user detached", c->self);
1545: }
1546: if (!chan_is_dead(c, 1))
1547: return;
1548: debug("channel %d: garbage collecting", c->self);
1549: channel_free(c);
1550: }
1551:
1.127 itojun 1552: static void
1.41 markus 1553: channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
1554: {
1555: static int did_init = 0;
1556: int i;
1557: Channel *c;
1.25 markus 1558:
1.41 markus 1559: if (!did_init) {
1560: channel_handler_init();
1561: did_init = 1;
1562: }
1563: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1564: c = channels[i];
1565: if (c == NULL)
1.41 markus 1566: continue;
1.118 markus 1567: if (ftab[c->type] != NULL)
1568: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1569: channel_garbage_collect(c);
1.1 deraadt 1570: }
1571: }
1572:
1.121 markus 1573: /*
1574: * Allocate/update select bitmasks and add any bits relevant to channels in
1575: * select bitmasks.
1576: */
1.49 markus 1577: void
1.100 markus 1578: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.132 markus 1579: int *nallocp, int rekeying)
1.41 markus 1580: {
1.84 markus 1581: int n;
1582: u_int sz;
1583:
1584: n = MAX(*maxfdp, channel_max_fd);
1585:
1586: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.132 markus 1587: /* perhaps check sz < nalloc/2 and shrink? */
1588: if (*readsetp == NULL || sz > *nallocp) {
1589: *readsetp = xrealloc(*readsetp, sz);
1590: *writesetp = xrealloc(*writesetp, sz);
1591: *nallocp = sz;
1.84 markus 1592: }
1.132 markus 1593: *maxfdp = n;
1.84 markus 1594: memset(*readsetp, 0, sz);
1595: memset(*writesetp, 0, sz);
1596:
1.100 markus 1597: if (!rekeying)
1598: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1599: }
1600:
1.121 markus 1601: /*
1602: * After select, perform any appropriate operations for channels which have
1603: * events pending.
1604: */
1.49 markus 1605: void
1.41 markus 1606: channel_after_select(fd_set * readset, fd_set * writeset)
1607: {
1608: channel_handler(channel_post, readset, writeset);
1609: }
1610:
1.121 markus 1611:
1.84 markus 1612: /* If there is data to send to the connection, enqueue some of it now. */
1.1 deraadt 1613:
1.49 markus 1614: void
1.142 itojun 1615: channel_output_poll(void)
1.1 deraadt 1616: {
1.25 markus 1617: int len, i;
1.41 markus 1618: Channel *c;
1.1 deraadt 1619:
1.25 markus 1620: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1621: c = channels[i];
1622: if (c == NULL)
1623: continue;
1.37 markus 1624:
1.121 markus 1625: /*
1626: * We are only interested in channels that can have buffered
1627: * incoming data.
1628: */
1.37 markus 1629: if (compat13) {
1.41 markus 1630: if (c->type != SSH_CHANNEL_OPEN &&
1631: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1632: continue;
1633: } else {
1.41 markus 1634: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1635: continue;
1636: }
1.46 markus 1637: if (compat20 &&
1638: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1639: /* XXX is this true? */
1.140 markus 1640: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1641: continue;
1642: }
1.25 markus 1643:
1644: /* Get the amount of buffered data for this channel. */
1.93 markus 1645: if ((c->istate == CHAN_INPUT_OPEN ||
1646: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1647: (len = buffer_len(&c->input)) > 0) {
1.121 markus 1648: /*
1649: * Send some data for the other side over the secure
1650: * connection.
1651: */
1.44 markus 1652: if (compat20) {
1653: if (len > c->remote_window)
1654: len = c->remote_window;
1655: if (len > c->remote_maxpacket)
1656: len = c->remote_maxpacket;
1.25 markus 1657: } else {
1.44 markus 1658: if (packet_is_interactive()) {
1659: if (len > 1024)
1660: len = 512;
1661: } else {
1662: /* Keep the packets at reasonable size. */
1663: if (len > packet_get_maxsize()/2)
1664: len = packet_get_maxsize()/2;
1665: }
1.25 markus 1666: }
1.41 markus 1667: if (len > 0) {
1.44 markus 1668: packet_start(compat20 ?
1669: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1670: packet_put_int(c->remote_id);
1671: packet_put_string(buffer_ptr(&c->input), len);
1672: packet_send();
1673: buffer_consume(&c->input, len);
1674: c->remote_window -= len;
1675: }
1676: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1677: if (compat13)
1678: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1679: /*
1680: * input-buffer is empty and read-socket shutdown:
1681: * tell peer, that we will not send more data: send IEOF
1682: */
1.41 markus 1683: chan_ibuf_empty(c);
1.25 markus 1684: }
1.44 markus 1685: /* Send extended data, i.e. stderr */
1686: if (compat20 &&
1687: c->remote_window > 0 &&
1688: (len = buffer_len(&c->extended)) > 0 &&
1689: c->extended_usage == CHAN_EXTENDED_READ) {
1.93 markus 1690: debug2("channel %d: rwin %d elen %d euse %d",
1691: c->self, c->remote_window, buffer_len(&c->extended),
1692: c->extended_usage);
1.44 markus 1693: if (len > c->remote_window)
1694: len = c->remote_window;
1695: if (len > c->remote_maxpacket)
1696: len = c->remote_maxpacket;
1697: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1698: packet_put_int(c->remote_id);
1699: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1700: packet_put_string(buffer_ptr(&c->extended), len);
1701: packet_send();
1702: buffer_consume(&c->extended, len);
1703: c->remote_window -= len;
1.93 markus 1704: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1705: }
1.25 markus 1706: }
1.1 deraadt 1707: }
1708:
1.121 markus 1709:
1710: /* -- protocol input */
1.1 deraadt 1711:
1.49 markus 1712: void
1.150 djm 1713: channel_input_data(int type, int plen, u_int32_t seq, void *ctxt)
1.1 deraadt 1714: {
1.37 markus 1715: int id;
1.25 markus 1716: char *data;
1.77 markus 1717: u_int data_len;
1.41 markus 1718: Channel *c;
1.25 markus 1719:
1720: /* Get the channel number and verify it. */
1.37 markus 1721: id = packet_get_int();
1.41 markus 1722: c = channel_lookup(id);
1723: if (c == NULL)
1.37 markus 1724: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 1725:
1726: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 1727: if (c->type != SSH_CHANNEL_OPEN &&
1728: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 1729: return;
1730:
1731: /* same for protocol 1.5 if output end is no longer open */
1.41 markus 1732: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
1.25 markus 1733: return;
1734:
1735: /* Get the data. */
1736: data = packet_get_string(&data_len);
1.41 markus 1737:
1.143 deraadt 1738: if (compat20) {
1.44 markus 1739: if (data_len > c->local_maxpacket) {
1740: log("channel %d: rcvd big packet %d, maxpack %d",
1741: c->self, data_len, c->local_maxpacket);
1742: }
1743: if (data_len > c->local_window) {
1744: log("channel %d: rcvd too much data %d, win %d",
1745: c->self, data_len, c->local_window);
1746: xfree(data);
1747: return;
1748: }
1749: c->local_window -= data_len;
1750: }
1.152 ! markus 1751: packet_check_eom();
1.41 markus 1752: buffer_append(&c->output, data, data_len);
1.25 markus 1753: xfree(data);
1.1 deraadt 1754: }
1.121 markus 1755:
1.49 markus 1756: void
1.150 djm 1757: channel_input_extended_data(int type, int plen, u_int32_t seq, void *ctxt)
1.44 markus 1758: {
1759: int id;
1760: int tcode;
1761: char *data;
1.77 markus 1762: u_int data_len;
1.44 markus 1763: Channel *c;
1764:
1765: /* Get the channel number and verify it. */
1766: id = packet_get_int();
1767: c = channel_lookup(id);
1768:
1769: if (c == NULL)
1770: packet_disconnect("Received extended_data for bad channel %d.", id);
1771: if (c->type != SSH_CHANNEL_OPEN) {
1772: log("channel %d: ext data for non open", id);
1773: return;
1774: }
1775: tcode = packet_get_int();
1776: if (c->efd == -1 ||
1777: c->extended_usage != CHAN_EXTENDED_WRITE ||
1778: tcode != SSH2_EXTENDED_DATA_STDERR) {
1779: log("channel %d: bad ext data", c->self);
1780: return;
1781: }
1782: data = packet_get_string(&data_len);
1.152 ! markus 1783: packet_check_eom();
1.44 markus 1784: if (data_len > c->local_window) {
1785: log("channel %d: rcvd too much extended_data %d, win %d",
1786: c->self, data_len, c->local_window);
1787: xfree(data);
1788: return;
1789: }
1.70 markus 1790: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 1791: c->local_window -= data_len;
1792: buffer_append(&c->extended, data, data_len);
1793: xfree(data);
1794: }
1795:
1.49 markus 1796: void
1.150 djm 1797: channel_input_ieof(int type, int plen, u_int32_t seq, void *ctxt)
1.41 markus 1798: {
1799: int id;
1800: Channel *c;
1801:
1802: id = packet_get_int();
1.152 ! markus 1803: packet_check_eom();
1.41 markus 1804: c = channel_lookup(id);
1805: if (c == NULL)
1806: packet_disconnect("Received ieof for nonexistent channel %d.", id);
1807: chan_rcvd_ieof(c);
1.133 markus 1808:
1809: /* XXX force input close */
1810: if (c->force_drain) {
1811: debug("channel %d: FORCE input drain", c->self);
1812: c->istate = CHAN_INPUT_WAIT_DRAIN;
1813: }
1814:
1.41 markus 1815: }
1.1 deraadt 1816:
1.49 markus 1817: void
1.150 djm 1818: channel_input_close(int type, int plen, u_int32_t seq, void *ctxt)
1.1 deraadt 1819: {
1.41 markus 1820: int id;
1821: Channel *c;
1.1 deraadt 1822:
1.41 markus 1823: id = packet_get_int();
1.152 ! markus 1824: packet_check_eom();
1.41 markus 1825: c = channel_lookup(id);
1826: if (c == NULL)
1827: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 1828:
1829: /*
1830: * Send a confirmation that we have closed the channel and no more
1831: * data is coming for it.
1832: */
1.25 markus 1833: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 1834: packet_put_int(c->remote_id);
1.25 markus 1835: packet_send();
1836:
1.27 markus 1837: /*
1838: * If the channel is in closed state, we have sent a close request,
1839: * and the other side will eventually respond with a confirmation.
1840: * Thus, we cannot free the channel here, because then there would be
1841: * no-one to receive the confirmation. The channel gets freed when
1842: * the confirmation arrives.
1843: */
1.41 markus 1844: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 1845: /*
1846: * Not a closed channel - mark it as draining, which will
1847: * cause it to be freed later.
1848: */
1.41 markus 1849: buffer_consume(&c->input, buffer_len(&c->input));
1850: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 1851: }
1.1 deraadt 1852: }
1853:
1.41 markus 1854: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.49 markus 1855: void
1.150 djm 1856: channel_input_oclose(int type, int plen, u_int32_t seq, void *ctxt)
1.41 markus 1857: {
1858: int id = packet_get_int();
1859: Channel *c = channel_lookup(id);
1.151 markus 1860:
1.152 ! markus 1861: packet_check_eom();
1.41 markus 1862: if (c == NULL)
1863: packet_disconnect("Received oclose for nonexistent channel %d.", id);
1864: chan_rcvd_oclose(c);
1865: }
1.1 deraadt 1866:
1.49 markus 1867: void
1.150 djm 1868: channel_input_close_confirmation(int type, int plen, u_int32_t seq, void *ctxt)
1.1 deraadt 1869: {
1.41 markus 1870: int id = packet_get_int();
1871: Channel *c = channel_lookup(id);
1.1 deraadt 1872:
1.152 ! markus 1873: packet_check_eom();
1.41 markus 1874: if (c == NULL)
1875: packet_disconnect("Received close confirmation for "
1876: "out-of-range channel %d.", id);
1877: if (c->type != SSH_CHANNEL_CLOSED)
1878: packet_disconnect("Received close confirmation for "
1879: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 1880: channel_free(c);
1.1 deraadt 1881: }
1882:
1.49 markus 1883: void
1.150 djm 1884: channel_input_open_confirmation(int type, int plen, u_int32_t seq, void *ctxt)
1.1 deraadt 1885: {
1.41 markus 1886: int id, remote_id;
1887: Channel *c;
1.1 deraadt 1888:
1.41 markus 1889: id = packet_get_int();
1890: c = channel_lookup(id);
1.25 markus 1891:
1.41 markus 1892: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1893: packet_disconnect("Received open confirmation for "
1894: "non-opening channel %d.", id);
1895: remote_id = packet_get_int();
1.27 markus 1896: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 1897: c->remote_id = remote_id;
1898: c->type = SSH_CHANNEL_OPEN;
1.44 markus 1899:
1900: if (compat20) {
1901: c->remote_window = packet_get_int();
1902: c->remote_maxpacket = packet_get_int();
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: }
1.152 ! markus 1911: packet_check_eom();
1.1 deraadt 1912: }
1913:
1.127 itojun 1914: static char *
1.114 markus 1915: reason2txt(int reason)
1916: {
1.143 deraadt 1917: switch (reason) {
1.114 markus 1918: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
1919: return "administratively prohibited";
1920: case SSH2_OPEN_CONNECT_FAILED:
1921: return "connect failed";
1922: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
1923: return "unknown channel type";
1924: case SSH2_OPEN_RESOURCE_SHORTAGE:
1925: return "resource shortage";
1926: }
1.117 stevesk 1927: return "unknown reason";
1.114 markus 1928: }
1929:
1.49 markus 1930: void
1.150 djm 1931: channel_input_open_failure(int type, int plen, u_int32_t seq, void *ctxt)
1.1 deraadt 1932: {
1.86 markus 1933: int id, reason;
1934: char *msg = NULL, *lang = NULL;
1.41 markus 1935: Channel *c;
1936:
1937: id = packet_get_int();
1938: c = channel_lookup(id);
1.25 markus 1939:
1.41 markus 1940: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1941: packet_disconnect("Received open failure for "
1942: "non-opening channel %d.", id);
1.44 markus 1943: if (compat20) {
1.86 markus 1944: reason = packet_get_int();
1.110 markus 1945: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 1946: msg = packet_get_string(NULL);
1947: lang = packet_get_string(NULL);
1948: }
1.114 markus 1949: log("channel %d: open failed: %s%s%s", id,
1950: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 1951: if (msg != NULL)
1952: xfree(msg);
1953: if (lang != NULL)
1954: xfree(lang);
1.44 markus 1955: }
1.152 ! markus 1956: packet_check_eom();
1.25 markus 1957: /* Free the channel. This will also close the socket. */
1.113 markus 1958: channel_free(c);
1.1 deraadt 1959: }
1960:
1.44 markus 1961: void
1.150 djm 1962: channel_input_channel_request(int type, int plen, u_int32_t seq, void *ctxt)
1.44 markus 1963: {
1964: int id;
1965: Channel *c;
1966:
1967: id = packet_get_int();
1968: c = channel_lookup(id);
1969:
1970: if (c == NULL ||
1971: (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1972: packet_disconnect("Received request for "
1973: "non-open channel %d.", id);
1974: if (c->cb_fn != NULL && c->cb_event == type) {
1.70 markus 1975: debug2("callback start");
1.44 markus 1976: c->cb_fn(c->self, c->cb_arg);
1.70 markus 1977: debug2("callback done");
1.44 markus 1978: } else {
1979: char *service = packet_get_string(NULL);
1.94 markus 1980: debug("channel %d: rcvd request for %s", c->self, service);
1.70 markus 1981: debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
1.44 markus 1982: xfree(service);
1983: }
1984: }
1985:
1.121 markus 1986: void
1.150 djm 1987: channel_input_window_adjust(int type, int plen, u_int32_t seq, void *ctxt)
1.121 markus 1988: {
1989: Channel *c;
1990: int id, adjust;
1991:
1992: if (!compat20)
1993: return;
1994:
1995: /* Get the channel number and verify it. */
1996: id = packet_get_int();
1997: c = channel_lookup(id);
1.1 deraadt 1998:
1.121 markus 1999: if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
2000: log("Received window adjust for "
2001: "non-open channel %d.", id);
2002: return;
2003: }
2004: adjust = packet_get_int();
1.152 ! markus 2005: packet_check_eom();
1.121 markus 2006: debug2("channel %d: rcvd adjust %d", id, adjust);
2007: c->remote_window += adjust;
2008: }
1.1 deraadt 2009:
1.121 markus 2010: void
1.150 djm 2011: channel_input_port_open(int type, int plen, u_int32_t seq, void *ctxt)
1.1 deraadt 2012: {
1.121 markus 2013: Channel *c = NULL;
2014: u_short host_port;
2015: char *host, *originator_string;
2016: int remote_id, sock = -1;
2017:
2018: remote_id = packet_get_int();
2019: host = packet_get_string(NULL);
2020: host_port = packet_get_int();
1.25 markus 2021:
1.121 markus 2022: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2023: originator_string = packet_get_string(NULL);
2024: } else {
2025: originator_string = xstrdup("unknown (remote did not supply name)");
2026: }
1.152 ! markus 2027: packet_check_eom();
1.121 markus 2028: sock = channel_connect_to(host, host_port);
2029: if (sock != -1) {
2030: c = channel_new("connected socket",
2031: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2032: originator_string, 1);
2033: if (c == NULL) {
2034: error("channel_input_port_open: channel_new failed");
2035: close(sock);
2036: } else {
2037: c->remote_id = remote_id;
1.25 markus 2038: }
2039: }
1.121 markus 2040: if (c == NULL) {
2041: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2042: packet_put_int(remote_id);
2043: packet_send();
2044: }
2045: xfree(host);
1.1 deraadt 2046: }
2047:
1.121 markus 2048:
2049: /* -- tcp forwarding */
1.135 markus 2050:
2051: void
2052: channel_set_af(int af)
2053: {
2054: IPv4or6 = af;
2055: }
1.121 markus 2056:
1.27 markus 2057: /*
2058: * Initiate forwarding of connections to local port "port" through the secure
2059: * channel to host:port from remote side.
2060: */
1.87 markus 2061: int
1.73 markus 2062: channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
2063: u_short port_to_connect, int gateway_ports)
2064: {
1.87 markus 2065: return channel_request_forwarding(
1.73 markus 2066: NULL, listen_port,
2067: host_to_connect, port_to_connect,
2068: gateway_ports, /*remote_fwd*/ 0);
2069: }
1.1 deraadt 2070:
1.73 markus 2071: /*
2072: * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
2073: * (SSH_CHANNEL_RPORT_LISTENER).
2074: */
1.87 markus 2075: int
1.73 markus 2076: channel_request_forwarding(
2077: const char *listen_address, u_short listen_port,
2078: const char *host_to_connect, u_short port_to_connect,
2079: int gateway_ports, int remote_fwd)
1.25 markus 2080: {
1.113 markus 2081: Channel *c;
1.121 markus 2082: int success, sock, on = 1, type;
1.35 markus 2083: struct addrinfo hints, *ai, *aitop;
2084: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.73 markus 2085: const char *host;
1.28 markus 2086: struct linger linger;
1.25 markus 2087:
1.87 markus 2088: success = 0;
2089:
1.73 markus 2090: if (remote_fwd) {
2091: host = listen_address;
1.121 markus 2092: type = SSH_CHANNEL_RPORT_LISTENER;
1.73 markus 2093: } else {
2094: host = host_to_connect;
1.121 markus 2095: type = SSH_CHANNEL_PORT_LISTENER;
1.73 markus 2096: }
2097:
1.113 markus 2098: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2099: error("Forward host name too long.");
2100: return success;
2101: }
1.25 markus 2102:
1.73 markus 2103: /* XXX listen_address is currently ignored */
1.28 markus 2104: /*
1.35 markus 2105: * getaddrinfo returns a loopback address if the hostname is
2106: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2107: */
1.35 markus 2108: memset(&hints, 0, sizeof(hints));
2109: hints.ai_family = IPv4or6;
2110: hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
2111: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2112: snprintf(strport, sizeof strport, "%d", listen_port);
1.35 markus 2113: if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
2114: packet_disconnect("getaddrinfo: fatal error");
2115:
2116: for (ai = aitop; ai; ai = ai->ai_next) {
2117: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2118: continue;
2119: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2120: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.73 markus 2121: error("channel_request_forwarding: getnameinfo failed");
1.35 markus 2122: continue;
2123: }
2124: /* Create a port to listen for the host. */
2125: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2126: if (sock < 0) {
2127: /* this is no error since kernel may not support ipv6 */
2128: verbose("socket: %.100s", strerror(errno));
2129: continue;
2130: }
2131: /*
2132: * Set socket options. We would like the socket to disappear
2133: * as soon as it has been closed for whatever reason.
2134: */
2135: setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
2136: linger.l_onoff = 1;
2137: linger.l_linger = 5;
2138: setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
2139: debug("Local forwarding listening on %s port %s.", ntop, strport);
2140:
2141: /* Bind the socket to the address. */
2142: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2143: /* address can be in use ipv6 address is already bound */
2144: verbose("bind: %.100s", strerror(errno));
2145: close(sock);
2146: continue;
2147: }
2148: /* Start listening for connections on the socket. */
2149: if (listen(sock, 5) < 0) {
2150: error("listen: %.100s", strerror(errno));
2151: close(sock);
2152: continue;
2153: }
2154: /* Allocate a channel number for the socket. */
1.121 markus 2155: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2156: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.71 markus 2157: 0, xstrdup("port listener"), 1);
1.113 markus 2158: if (c == NULL) {
2159: error("channel_request_forwarding: channel_new failed");
2160: close(sock);
2161: continue;
2162: }
2163: strlcpy(c->path, host, sizeof(c->path));
2164: c->host_port = port_to_connect;
2165: c->listening_port = listen_port;
1.35 markus 2166: success = 1;
2167: }
2168: if (success == 0)
1.87 markus 2169: error("channel_request_forwarding: cannot listen to port: %d",
2170: listen_port);
1.35 markus 2171: freeaddrinfo(aitop);
1.87 markus 2172: return success;
1.25 markus 2173: }
1.1 deraadt 2174:
1.27 markus 2175: /*
2176: * Initiate forwarding of connections to port "port" on remote host through
2177: * the secure channel to host:port from local side.
2178: */
1.1 deraadt 2179:
1.49 markus 2180: void
1.73 markus 2181: channel_request_remote_forwarding(u_short listen_port,
2182: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2183: {
1.73 markus 2184: int payload_len, type, success = 0;
2185:
1.25 markus 2186: /* Record locally that connection to this host/port is permitted. */
2187: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2188: fatal("channel_request_remote_forwarding: too many forwards");
2189:
2190: /* Send the forward request to the remote side. */
1.44 markus 2191: if (compat20) {
2192: const char *address_to_bind = "0.0.0.0";
2193: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2194: packet_put_cstring("tcpip-forward");
2195: packet_put_char(0); /* boolean: want reply */
2196: packet_put_cstring(address_to_bind);
2197: packet_put_int(listen_port);
1.73 markus 2198: packet_send();
2199: packet_write_wait();
2200: /* Assume that server accepts the request */
2201: success = 1;
1.44 markus 2202: } else {
2203: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2204: packet_put_int(listen_port);
2205: packet_put_cstring(host_to_connect);
1.44 markus 2206: packet_put_int(port_to_connect);
2207: packet_send();
2208: packet_write_wait();
1.73 markus 2209:
2210: /* Wait for response from the remote side. */
2211: type = packet_read(&payload_len);
2212: switch (type) {
2213: case SSH_SMSG_SUCCESS:
2214: success = 1;
2215: break;
2216: case SSH_SMSG_FAILURE:
2217: log("Warning: Server denied remote port forwarding.");
2218: break;
2219: default:
2220: /* Unknown packet */
2221: packet_disconnect("Protocol error for port forward request:"
2222: "received packet type %d.", type);
2223: }
2224: }
2225: if (success) {
2226: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2227: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2228: permitted_opens[num_permitted_opens].listen_port = listen_port;
2229: num_permitted_opens++;
1.44 markus 2230: }
1.1 deraadt 2231: }
2232:
1.27 markus 2233: /*
2234: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2235: * listening for the port, and sends back a success reply (or disconnect
2236: * message if there was an error). This never returns if there was an error.
2237: */
1.1 deraadt 2238:
1.49 markus 2239: void
1.56 markus 2240: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2241: {
1.31 markus 2242: u_short port, host_port;
1.25 markus 2243: char *hostname;
1.1 deraadt 2244:
1.25 markus 2245: /* Get arguments from the packet. */
2246: port = packet_get_int();
2247: hostname = packet_get_string(NULL);
2248: host_port = packet_get_int();
2249:
1.27 markus 2250: /*
2251: * Check that an unprivileged user is not trying to forward a
2252: * privileged port.
2253: */
1.25 markus 2254: if (port < IPPORT_RESERVED && !is_root)
2255: packet_disconnect("Requested forwarding of port %d but user is not root.",
2256: port);
1.73 markus 2257: /* Initiate forwarding */
1.56 markus 2258: channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
1.25 markus 2259:
2260: /* Free the argument string. */
2261: xfree(hostname);
1.1 deraadt 2262: }
2263:
1.99 markus 2264: /*
2265: * Permits opening to any host/port if permitted_opens[] is empty. This is
2266: * usually called by the server, because the user could connect to any port
2267: * anyway, and the server has no way to know but to trust the client anyway.
2268: */
2269: void
1.142 itojun 2270: channel_permit_all_opens(void)
1.99 markus 2271: {
2272: if (num_permitted_opens == 0)
2273: all_opens_permitted = 1;
2274: }
2275:
1.101 markus 2276: void
1.99 markus 2277: channel_add_permitted_opens(char *host, int port)
2278: {
2279: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2280: fatal("channel_request_remote_forwarding: too many forwards");
2281: debug("allow port forwarding to host %s port %d", host, port);
2282:
2283: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2284: permitted_opens[num_permitted_opens].port_to_connect = port;
2285: num_permitted_opens++;
2286:
2287: all_opens_permitted = 0;
2288: }
2289:
1.101 markus 2290: void
1.99 markus 2291: channel_clear_permitted_opens(void)
2292: {
2293: int i;
2294:
2295: for (i = 0; i < num_permitted_opens; i++)
2296: xfree(permitted_opens[i].host_to_connect);
2297: num_permitted_opens = 0;
2298:
2299: }
2300:
2301:
2302: /* return socket to remote host, port */
1.127 itojun 2303: static int
1.99 markus 2304: connect_to(const char *host, u_short port)
1.41 markus 2305: {
2306: struct addrinfo hints, *ai, *aitop;
2307: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2308: int gaierr;
2309: int sock = -1;
2310:
2311: memset(&hints, 0, sizeof(hints));
2312: hints.ai_family = IPv4or6;
2313: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2314: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2315: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2316: error("connect_to %.100s: unknown host (%s)", host,
2317: gai_strerror(gaierr));
1.41 markus 2318: return -1;
2319: }
2320: for (ai = aitop; ai; ai = ai->ai_next) {
2321: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2322: continue;
2323: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2324: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2325: error("connect_to: getnameinfo failed");
1.41 markus 2326: continue;
2327: }
2328: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2329: if (sock < 0) {
2330: error("socket: %.100s", strerror(errno));
2331: continue;
2332: }
1.80 markus 2333: if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
1.75 markus 2334: fatal("connect_to: F_SETFL: %s", strerror(errno));
2335: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2336: errno != EINPROGRESS) {
1.99 markus 2337: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2338: strerror(errno));
2339: close(sock);
1.89 stevesk 2340: continue; /* fail -- try next */
1.41 markus 2341: }
2342: break; /* success */
2343:
2344: }
2345: freeaddrinfo(aitop);
2346: if (!ai) {
1.99 markus 2347: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2348: return -1;
2349: }
2350: /* success */
2351: return sock;
2352: }
1.99 markus 2353:
1.73 markus 2354: int
1.130 stevesk 2355: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2356: {
2357: int i;
1.99 markus 2358:
1.73 markus 2359: for (i = 0; i < num_permitted_opens; i++)
2360: if (permitted_opens[i].listen_port == listen_port)
1.99 markus 2361: return connect_to(
1.73 markus 2362: permitted_opens[i].host_to_connect,
2363: permitted_opens[i].port_to_connect);
1.74 markus 2364: error("WARNING: Server requests forwarding for unknown listen_port %d",
2365: listen_port);
1.73 markus 2366: return -1;
2367: }
2368:
1.99 markus 2369: /* Check if connecting to that port is permitted and connect. */
2370: int
2371: channel_connect_to(const char *host, u_short port)
2372: {
2373: int i, permit;
2374:
2375: permit = all_opens_permitted;
2376: if (!permit) {
2377: for (i = 0; i < num_permitted_opens; i++)
2378: if (permitted_opens[i].port_to_connect == port &&
2379: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2380: permit = 1;
2381:
2382: }
2383: if (!permit) {
2384: log("Received request to connect to host %.100s port %d, "
2385: "but the request was denied.", host, port);
2386: return -1;
2387: }
2388: return connect_to(host, port);
2389: }
2390:
1.121 markus 2391: /* -- X11 forwarding */
1.1 deraadt 2392:
1.27 markus 2393: /*
2394: * Creates an internet domain socket for listening for X11 connections.
1.141 stevesk 2395: * Returns a suitable display number for the DISPLAY variable, or -1 if
2396: * an error occurs.
1.27 markus 2397: */
1.141 stevesk 2398: int
1.149 markus 2399: x11_create_display_inet(int x11_display_offset, int gateway_ports,
2400: int single_connection)
1.1 deraadt 2401: {
1.149 markus 2402: Channel *nc = NULL;
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;
1.148 deraadt 2410: display_number < MAX_DISPLAYS;
2411: display_number++) {
1.25 markus 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];
1.149 markus 2464: nc = channel_new("x11 listener",
1.51 markus 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);
1.149 markus 2468: if (nc != NULL)
2469: nc->single_connection = single_connection;
1.35 markus 2470: }
1.1 deraadt 2471:
1.141 stevesk 2472: /* Return the display number for the DISPLAY environment variable. */
2473: return display_number;
1.1 deraadt 2474: }
2475:
1.127 itojun 2476: static int
1.77 markus 2477: connect_local_xsocket(u_int dnr)
1.1 deraadt 2478: {
1.25 markus 2479: int sock;
2480: struct sockaddr_un addr;
2481:
1.147 stevesk 2482: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2483: if (sock < 0)
2484: error("socket: %.100s", strerror(errno));
2485: memset(&addr, 0, sizeof(addr));
2486: addr.sun_family = AF_UNIX;
2487: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
2488: if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2489: return sock;
2490: close(sock);
1.25 markus 2491: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2492: return -1;
1.1 deraadt 2493: }
2494:
1.51 markus 2495: int
2496: x11_connect_display(void)
1.1 deraadt 2497: {
1.146 stevesk 2498: int display_number, sock = 0, on = 1;
1.25 markus 2499: const char *display;
1.51 markus 2500: char buf[1024], *cp;
1.35 markus 2501: struct addrinfo hints, *ai, *aitop;
2502: char strport[NI_MAXSERV];
2503: int gaierr;
1.25 markus 2504:
2505: /* Try to open a socket for the local X server. */
2506: display = getenv("DISPLAY");
2507: if (!display) {
2508: error("DISPLAY not set.");
1.51 markus 2509: return -1;
1.25 markus 2510: }
1.27 markus 2511: /*
2512: * Now we decode the value of the DISPLAY variable and make a
2513: * connection to the real X server.
2514: */
2515:
2516: /*
2517: * Check if it is a unix domain socket. Unix domain displays are in
2518: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2519: */
1.25 markus 2520: if (strncmp(display, "unix:", 5) == 0 ||
2521: display[0] == ':') {
2522: /* Connect to the unix domain socket. */
2523: if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2524: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2525: display);
1.51 markus 2526: return -1;
1.25 markus 2527: }
2528: /* Create a socket. */
2529: sock = connect_local_xsocket(display_number);
2530: if (sock < 0)
1.51 markus 2531: return -1;
1.25 markus 2532:
2533: /* OK, we now have a connection to the display. */
1.51 markus 2534: return sock;
1.25 markus 2535: }
1.27 markus 2536: /*
2537: * Connect to an inet socket. The DISPLAY value is supposedly
2538: * hostname:d[.s], where hostname may also be numeric IP address.
2539: */
1.145 stevesk 2540: strlcpy(buf, display, sizeof(buf));
1.25 markus 2541: cp = strchr(buf, ':');
2542: if (!cp) {
2543: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 2544: return -1;
1.25 markus 2545: }
2546: *cp = 0;
1.27 markus 2547: /* buf now contains the host name. But first we parse the display number. */
1.25 markus 2548: if (sscanf(cp + 1, "%d", &display_number) != 1) {
2549: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2550: display);
1.51 markus 2551: return -1;
1.25 markus 2552: }
1.35 markus 2553:
2554: /* Look up the host address */
2555: memset(&hints, 0, sizeof(hints));
2556: hints.ai_family = IPv4or6;
2557: hints.ai_socktype = SOCK_STREAM;
2558: snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2559: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2560: error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
1.51 markus 2561: return -1;
1.25 markus 2562: }
1.35 markus 2563: for (ai = aitop; ai; ai = ai->ai_next) {
2564: /* Create a socket. */
2565: sock = socket(ai->ai_family, SOCK_STREAM, 0);
2566: if (sock < 0) {
2567: debug("socket: %.100s", strerror(errno));
1.41 markus 2568: continue;
2569: }
2570: /* Connect it to the display. */
2571: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2572: debug("connect %.100s port %d: %.100s", buf,
2573: 6000 + display_number, strerror(errno));
2574: close(sock);
2575: continue;
2576: }
2577: /* Success */
2578: break;
1.35 markus 2579: }
2580: freeaddrinfo(aitop);
2581: if (!ai) {
1.49 markus 2582: error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
1.35 markus 2583: strerror(errno));
1.51 markus 2584: return -1;
1.25 markus 2585: }
1.146 stevesk 2586: if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on) == -1)
2587: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
1.51 markus 2588: return sock;
2589: }
2590:
2591: /*
2592: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2593: * the remote channel number. We should do whatever we want, and respond
2594: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2595: */
2596:
2597: void
1.150 djm 2598: x11_input_open(int type, int plen, u_int32_t seq, void *ctxt)
1.51 markus 2599: {
1.113 markus 2600: Channel *c = NULL;
2601: int remote_id, sock = 0;
1.51 markus 2602: char *remote_host;
1.25 markus 2603:
1.113 markus 2604: debug("Received X11 open request.");
1.51 markus 2605:
1.113 markus 2606: remote_id = packet_get_int();
1.121 markus 2607:
2608: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 2609: remote_host = packet_get_string(NULL);
1.51 markus 2610: } else {
2611: remote_host = xstrdup("unknown (remote did not supply name)");
2612: }
1.152 ! markus 2613: packet_check_eom();
1.25 markus 2614:
1.51 markus 2615: /* Obtain a connection to the real X display. */
2616: sock = x11_connect_display();
1.113 markus 2617: if (sock != -1) {
2618: /* Allocate a channel for this connection. */
2619: c = channel_new("connected x11 socket",
2620: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
2621: remote_host, 1);
2622: if (c == NULL) {
2623: error("x11_input_open: channel_new failed");
2624: close(sock);
2625: } else {
2626: c->remote_id = remote_id;
1.133 markus 2627: c->force_drain = 1;
1.113 markus 2628: }
2629: }
2630: if (c == NULL) {
1.51 markus 2631: /* Send refusal to the remote host. */
2632: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2633: packet_put_int(remote_id);
1.51 markus 2634: } else {
2635: /* Send a confirmation to the remote host. */
2636: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 2637: packet_put_int(remote_id);
2638: packet_put_int(c->self);
1.51 markus 2639: }
1.113 markus 2640: packet_send();
1.72 markus 2641: }
2642:
2643: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2644: void
1.150 djm 2645: deny_input_open(int type, int plen, u_int32_t seq, void *ctxt)
1.72 markus 2646: {
2647: int rchan = packet_get_int();
1.143 deraadt 2648: switch (type) {
1.72 markus 2649: case SSH_SMSG_AGENT_OPEN:
2650: error("Warning: ssh server tried agent forwarding.");
2651: break;
2652: case SSH_SMSG_X11_OPEN:
2653: error("Warning: ssh server tried X11 forwarding.");
2654: break;
2655: default:
2656: error("deny_input_open: type %d plen %d", type, plen);
2657: break;
2658: }
2659: error("Warning: this is probably a break in attempt by a malicious server.");
2660: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2661: packet_put_int(rchan);
2662: packet_send();
1.1 deraadt 2663: }
2664:
1.27 markus 2665: /*
2666: * Requests forwarding of X11 connections, generates fake authentication
2667: * data, and enables authentication spoofing.
1.121 markus 2668: * This should be called in the client only.
1.27 markus 2669: */
1.49 markus 2670: void
1.51 markus 2671: x11_request_forwarding_with_spoofing(int client_session_id,
2672: const char *proto, const char *data)
1.1 deraadt 2673: {
1.77 markus 2674: u_int data_len = (u_int) strlen(data) / 2;
1.90 markus 2675: u_int i, value, len;
1.25 markus 2676: char *new_data;
2677: int screen_number;
2678: const char *cp;
2679: u_int32_t rand = 0;
2680:
2681: cp = getenv("DISPLAY");
2682: if (cp)
2683: cp = strchr(cp, ':');
2684: if (cp)
2685: cp = strchr(cp, '.');
2686: if (cp)
2687: screen_number = atoi(cp + 1);
2688: else
2689: screen_number = 0;
2690:
2691: /* Save protocol name. */
2692: x11_saved_proto = xstrdup(proto);
2693:
1.27 markus 2694: /*
2695: * Extract real authentication data and generate fake data of the
2696: * same length.
2697: */
1.25 markus 2698: x11_saved_data = xmalloc(data_len);
2699: x11_fake_data = xmalloc(data_len);
2700: for (i = 0; i < data_len; i++) {
2701: if (sscanf(data + 2 * i, "%2x", &value) != 1)
2702: fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2703: if (i % 4 == 0)
2704: rand = arc4random();
2705: x11_saved_data[i] = value;
2706: x11_fake_data[i] = rand & 0xff;
2707: rand >>= 8;
2708: }
2709: x11_saved_data_len = data_len;
2710: x11_fake_data_len = data_len;
2711:
2712: /* Convert the fake data into hex. */
1.90 markus 2713: len = 2 * data_len + 1;
2714: new_data = xmalloc(len);
1.25 markus 2715: for (i = 0; i < data_len; i++)
1.90 markus 2716: snprintf(new_data + 2 * i, len - 2 * i,
2717: "%02x", (u_char) x11_fake_data[i]);
1.25 markus 2718:
2719: /* Send the request packet. */
1.51 markus 2720: if (compat20) {
2721: channel_request_start(client_session_id, "x11-req", 0);
2722: packet_put_char(0); /* XXX bool single connection */
2723: } else {
2724: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2725: }
2726: packet_put_cstring(proto);
2727: packet_put_cstring(new_data);
1.25 markus 2728: packet_put_int(screen_number);
2729: packet_send();
2730: packet_write_wait();
2731: xfree(new_data);
1.1 deraadt 2732: }
2733:
1.121 markus 2734:
2735: /* -- agent forwarding */
2736:
1.1 deraadt 2737: /* Sends a message to the server to request authentication fd forwarding. */
2738:
1.49 markus 2739: void
1.142 itojun 2740: auth_request_forwarding(void)
1.1 deraadt 2741: {
1.25 markus 2742: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2743: packet_send();
2744: packet_write_wait();
1.1 deraadt 2745: }
2746:
1.27 markus 2747: /*
2748: * Returns the name of the forwarded authentication socket. Returns NULL if
2749: * there is no forwarded authentication socket. The returned value points to
2750: * a static buffer.
2751: */
1.1 deraadt 2752:
1.25 markus 2753: char *
1.142 itojun 2754: auth_get_socket_name(void)
1.1 deraadt 2755: {
1.121 markus 2756: return auth_sock_name;
1.1 deraadt 2757: }
2758:
1.12 markus 2759: /* removes the agent forwarding socket */
2760:
1.49 markus 2761: void
1.123 markus 2762: auth_sock_cleanup_proc(void *_pw)
1.25 markus 2763: {
1.123 markus 2764: struct passwd *pw = _pw;
2765:
1.122 markus 2766: if (auth_sock_name) {
1.123 markus 2767: temporarily_use_uid(pw);
1.122 markus 2768: unlink(auth_sock_name);
2769: rmdir(auth_sock_dir);
2770: auth_sock_name = NULL;
1.123 markus 2771: restore_uid();
1.122 markus 2772: }
1.12 markus 2773: }
2774:
1.27 markus 2775: /*
1.59 markus 2776: * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
1.27 markus 2777: * This starts forwarding authentication requests.
2778: */
1.1 deraadt 2779:
1.59 markus 2780: int
1.25 markus 2781: auth_input_request_forwarding(struct passwd * pw)
1.1 deraadt 2782: {
1.113 markus 2783: Channel *nc;
2784: int sock;
1.25 markus 2785: struct sockaddr_un sunaddr;
2786:
1.121 markus 2787: if (auth_get_socket_name() != NULL) {
2788: error("authentication forwarding requested twice.");
2789: return 0;
2790: }
1.25 markus 2791:
2792: /* Temporarily drop privileged uid for mkdir/bind. */
1.102 markus 2793: temporarily_use_uid(pw);
1.25 markus 2794:
2795: /* Allocate a buffer for the socket name, and format the name. */
1.121 markus 2796: auth_sock_name = xmalloc(MAXPATHLEN);
2797: auth_sock_dir = xmalloc(MAXPATHLEN);
2798: strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
1.25 markus 2799:
2800: /* Create private directory for socket */
1.121 markus 2801: if (mkdtemp(auth_sock_dir) == NULL) {
2802: packet_send_debug("Agent forwarding disabled: "
2803: "mkdtemp() failed: %.100s", strerror(errno));
1.59 markus 2804: restore_uid();
1.121 markus 2805: xfree(auth_sock_name);
2806: xfree(auth_sock_dir);
2807: auth_sock_name = NULL;
2808: auth_sock_dir = NULL;
1.59 markus 2809: return 0;
2810: }
1.121 markus 2811: snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%d",
2812: auth_sock_dir, (int) getpid());
1.25 markus 2813:
1.122 markus 2814: /* delete agent socket on fatal() */
1.123 markus 2815: fatal_add_cleanup(auth_sock_cleanup_proc, pw);
1.122 markus 2816:
1.25 markus 2817: /* Create the socket. */
2818: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2819: if (sock < 0)
2820: packet_disconnect("socket: %.100s", strerror(errno));
2821:
2822: /* Bind it to the name. */
2823: memset(&sunaddr, 0, sizeof(sunaddr));
2824: sunaddr.sun_family = AF_UNIX;
1.145 stevesk 2825: strlcpy(sunaddr.sun_path, auth_sock_name, sizeof(sunaddr.sun_path));
1.25 markus 2826:
2827: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2828: packet_disconnect("bind: %.100s", strerror(errno));
2829:
2830: /* Restore the privileged uid. */
2831: restore_uid();
2832:
2833: /* Start listening on the socket. */
2834: if (listen(sock, 5) < 0)
2835: packet_disconnect("listen: %.100s", strerror(errno));
2836:
2837: /* Allocate a channel for the authentication agent socket. */
1.113 markus 2838: nc = channel_new("auth socket",
1.73 markus 2839: SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2840: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2841: 0, xstrdup("auth socket"), 1);
1.113 markus 2842: if (nc == NULL) {
2843: error("auth_input_request_forwarding: channel_new failed");
1.123 markus 2844: auth_sock_cleanup_proc(pw);
1.124 markus 2845: fatal_remove_cleanup(auth_sock_cleanup_proc, pw);
1.113 markus 2846: close(sock);
2847: return 0;
2848: }
1.121 markus 2849: strlcpy(nc->path, auth_sock_name, sizeof(nc->path));
1.59 markus 2850: return 1;
1.1 deraadt 2851: }
2852:
2853: /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2854:
1.49 markus 2855: void
1.150 djm 2856: auth_input_open_request(int type, int plen, u_int32_t seq, void *ctxt)
1.1 deraadt 2857: {
1.113 markus 2858: Channel *c = NULL;
2859: int remote_id, sock;
1.121 markus 2860: char *name;
1.41 markus 2861:
1.25 markus 2862: /* Read the remote channel number from the message. */
1.113 markus 2863: remote_id = packet_get_int();
1.152 ! markus 2864: packet_check_eom();
1.25 markus 2865:
1.27 markus 2866: /*
2867: * Get a connection to the local authentication agent (this may again
2868: * get forwarded).
2869: */
1.25 markus 2870: sock = ssh_get_authentication_socket();
2871:
1.27 markus 2872: /*
2873: * If we could not connect the agent, send an error message back to
2874: * the server. This should never happen unless the agent dies,
2875: * because authentication forwarding is only enabled if we have an
2876: * agent.
2877: */
1.113 markus 2878: if (sock >= 0) {
1.121 markus 2879: name = xstrdup("authentication agent connection");
2880: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
2881: -1, 0, 0, 0, name, 1);
1.113 markus 2882: if (c == NULL) {
2883: error("auth_input_open_request: channel_new failed");
1.121 markus 2884: xfree(name);
1.113 markus 2885: close(sock);
2886: } else {
2887: c->remote_id = remote_id;
1.133 markus 2888: c->force_drain = 1;
1.113 markus 2889: }
2890: }
2891: if (c == NULL) {
1.25 markus 2892: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 2893: packet_put_int(remote_id);
2894: } else {
2895: /* Send a confirmation to the remote host. */
2896: debug("Forwarding authentication connection.");
2897: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2898: packet_put_int(remote_id);
2899: packet_put_int(c->self);
1.25 markus 2900: }
2901: packet_send();
1.1 deraadt 2902: }