Annotation of src/usr.bin/ssh/channels.c, Revision 1.257
1.257 ! dtucker 1: /* $OpenBSD: channels.c,v 1.256 2006/07/17 01:31:09 stevesk Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
42: #include "includes.h"
1.234 stevesk 43:
44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/types.h>
46: #include <sys/un.h>
1.251 stevesk 47: #include <sys/socket.h>
48:
49: #include <netinet/in.h>
50: #include <arpa/inet.h>
1.233 stevesk 51:
1.254 stevesk 52: #include <errno.h>
1.255 stevesk 53: #include <netdb.h>
1.233 stevesk 54: #include <termios.h>
1.256 stevesk 55: #include <unistd.h>
1.1 deraadt 56:
57: #include "ssh.h"
1.82 markus 58: #include "ssh1.h"
59: #include "ssh2.h"
1.1 deraadt 60: #include "packet.h"
61: #include "xmalloc.h"
1.82 markus 62: #include "log.h"
63: #include "misc.h"
1.14 markus 64: #include "channels.h"
65: #include "compat.h"
1.82 markus 66: #include "canohost.h"
1.64 markus 67: #include "key.h"
68: #include "authfd.h"
1.147 stevesk 69: #include "pathnames.h"
1.193 markus 70: #include "bufaux.h"
1.1 deraadt 71:
1.121 markus 72: /* -- channel core */
1.12 markus 73:
1.27 markus 74: /*
75: * Pointer to an array containing all allocated channels. The array is
76: * dynamically extended as needed.
77: */
1.113 markus 78: static Channel **channels = NULL;
1.1 deraadt 79:
1.27 markus 80: /*
81: * Size of the channel array. All slots of the array must always be
1.113 markus 82: * initialized (at least the type field); unused slots set to NULL
1.27 markus 83: */
1.209 avsm 84: static u_int channels_alloc = 0;
1.1 deraadt 85:
1.27 markus 86: /*
87: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 88: * updated in channel_new.
1.27 markus 89: */
1.84 markus 90: static int channel_max_fd = 0;
1.1 deraadt 91:
92:
1.121 markus 93: /* -- tcp forwarding */
1.1 deraadt 94:
1.27 markus 95: /*
96: * Data structure for storing which hosts are permitted for forward requests.
97: * The local sides of any remote forwards are stored in this array to prevent
98: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
99: * network (which might be behind a firewall).
100: */
1.25 markus 101: typedef struct {
1.41 markus 102: char *host_to_connect; /* Connect to 'host'. */
103: u_short port_to_connect; /* Connect to 'port'. */
104: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 105: } ForwardPermission;
106:
1.257 ! dtucker 107: /* List of all permitted host/port pairs to connect by the user. */
1.1 deraadt 108: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 109:
1.257 ! dtucker 110: /* List of all permitted host/port pairs to connect by the admin. */
! 111: static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
! 112:
! 113: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 114: static int num_permitted_opens = 0;
1.257 ! dtucker 115:
! 116: /* Number of permitted host/port pair in the array permitted by the admin. */
! 117: static int num_adm_permitted_opens = 0;
! 118:
1.27 markus 119: /*
120: * If this is true, all opens are permitted. This is the case on the server
121: * on which we have to trust the client anyway, and the user could do
122: * anything after logging in anyway.
123: */
1.1 deraadt 124: static int all_opens_permitted = 0;
125:
1.121 markus 126:
127: /* -- X11 forwarding */
128:
129: /* Maximum number of fake X11 displays to try. */
130: #define MAX_DISPLAYS 1000
131:
1.219 djm 132: /* Saved X11 local (client) display. */
133: static char *x11_saved_display = NULL;
134:
1.121 markus 135: /* Saved X11 authentication protocol name. */
136: static char *x11_saved_proto = NULL;
137:
138: /* Saved X11 authentication data. This is the real data. */
139: static char *x11_saved_data = NULL;
140: static u_int x11_saved_data_len = 0;
141:
142: /*
143: * Fake X11 authentication data. This is what the server will be sending us;
144: * we should replace any occurrences of this by the real data.
145: */
1.240 deraadt 146: static u_char *x11_fake_data = NULL;
1.121 markus 147: static u_int x11_fake_data_len;
148:
149:
150: /* -- agent forwarding */
151:
152: #define NUM_SOCKS 10
153:
1.82 markus 154: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 155: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 156:
1.121 markus 157: /* helper */
1.127 itojun 158: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 159:
1.121 markus 160: /* -- channel core */
1.41 markus 161:
162: Channel *
1.229 markus 163: channel_by_id(int id)
1.41 markus 164: {
165: Channel *c;
1.113 markus 166:
1.209 avsm 167: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 168: logit("channel_by_id: %d: bad id", id);
1.41 markus 169: return NULL;
170: }
1.113 markus 171: c = channels[id];
172: if (c == NULL) {
1.229 markus 173: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 174: return NULL;
175: }
176: return c;
1.55 markus 177: }
178:
1.27 markus 179: /*
1.229 markus 180: * Returns the channel if it is allowed to receive protocol messages.
181: * Private channels, like listening sockets, may not receive messages.
182: */
183: Channel *
184: channel_lookup(int id)
185: {
186: Channel *c;
187:
188: if ((c = channel_by_id(id)) == NULL)
189: return (NULL);
190:
1.237 deraadt 191: switch (c->type) {
1.229 markus 192: case SSH_CHANNEL_X11_OPEN:
193: case SSH_CHANNEL_LARVAL:
194: case SSH_CHANNEL_CONNECTING:
195: case SSH_CHANNEL_DYNAMIC:
196: case SSH_CHANNEL_OPENING:
197: case SSH_CHANNEL_OPEN:
198: case SSH_CHANNEL_INPUT_DRAINING:
199: case SSH_CHANNEL_OUTPUT_DRAINING:
200: return (c);
201: }
202: logit("Non-public channel %d, type %d.", id, c->type);
203: return (NULL);
204: }
205:
206: /*
1.55 markus 207: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 208: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 209: */
1.127 itojun 210: static void
1.71 markus 211: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
212: int extusage, int nonblock)
1.1 deraadt 213: {
1.25 markus 214: /* Update the maximum file descriptor value. */
1.84 markus 215: channel_max_fd = MAX(channel_max_fd, rfd);
216: channel_max_fd = MAX(channel_max_fd, wfd);
217: channel_max_fd = MAX(channel_max_fd, efd);
218:
1.27 markus 219: /* XXX set close-on-exec -markus */
1.55 markus 220:
1.52 markus 221: c->rfd = rfd;
222: c->wfd = wfd;
223: c->sock = (rfd == wfd) ? rfd : -1;
1.204 djm 224: c->ctl_fd = -1; /* XXX: set elsewhere */
1.52 markus 225: c->efd = efd;
226: c->extended_usage = extusage;
1.71 markus 227:
1.91 markus 228: /* XXX ugly hack: nonblock is only set by the server */
229: if (nonblock && isatty(c->rfd)) {
1.194 markus 230: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 231: c->isatty = 1;
232: if (!isatty(c->wfd)) {
1.94 markus 233: error("channel %d: wfd %d is not a tty?",
1.91 markus 234: c->self, c->wfd);
235: }
236: } else {
237: c->isatty = 0;
238: }
239:
1.71 markus 240: /* enable nonblocking mode */
241: if (nonblock) {
242: if (rfd != -1)
243: set_nonblock(rfd);
244: if (wfd != -1)
245: set_nonblock(wfd);
246: if (efd != -1)
247: set_nonblock(efd);
248: }
1.52 markus 249: }
250:
251: /*
252: * Allocate a new channel object and set its type and socket. This will cause
253: * remote_name to be freed.
254: */
1.113 markus 255: Channel *
1.52 markus 256: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 257: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 258: {
1.209 avsm 259: int found;
260: u_int i;
1.52 markus 261: Channel *c;
1.25 markus 262:
263: /* Do initial allocation if this is the first call. */
264: if (channels_alloc == 0) {
265: channels_alloc = 10;
1.242 djm 266: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 267: for (i = 0; i < channels_alloc; i++)
1.113 markus 268: channels[i] = NULL;
1.25 markus 269: }
270: /* Try to find a free slot where to put the new channel. */
271: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 272: if (channels[i] == NULL) {
1.25 markus 273: /* Found a free slot. */
1.209 avsm 274: found = (int)i;
1.25 markus 275: break;
276: }
1.209 avsm 277: if (found < 0) {
1.27 markus 278: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 279: found = channels_alloc;
1.179 markus 280: if (channels_alloc > 10000)
281: fatal("channel_new: internal error: channels_alloc %d "
282: "too big.", channels_alloc);
1.243 djm 283: channels = xrealloc(channels, channels_alloc + 10,
284: sizeof(Channel *));
1.195 markus 285: channels_alloc += 10;
1.70 markus 286: debug2("channel: expanding %d", channels_alloc);
1.25 markus 287: for (i = found; i < channels_alloc; i++)
1.113 markus 288: channels[i] = NULL;
1.25 markus 289: }
1.113 markus 290: /* Initialize and return new channel. */
1.242 djm 291: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 292: buffer_init(&c->input);
293: buffer_init(&c->output);
1.41 markus 294: buffer_init(&c->extended);
1.159 markus 295: c->ostate = CHAN_OUTPUT_OPEN;
296: c->istate = CHAN_INPUT_OPEN;
297: c->flags = 0;
1.71 markus 298: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
1.25 markus 299: c->self = found;
300: c->type = type;
1.41 markus 301: c->ctype = ctype;
1.51 markus 302: c->local_window = window;
303: c->local_window_max = window;
304: c->local_consumed = 0;
305: c->local_maxpacket = maxpack;
1.25 markus 306: c->remote_id = -1;
1.190 markus 307: c->remote_name = xstrdup(remote_name);
1.41 markus 308: c->remote_window = 0;
309: c->remote_maxpacket = 0;
1.133 markus 310: c->force_drain = 0;
1.149 markus 311: c->single_connection = 0;
1.131 markus 312: c->detach_user = NULL;
1.225 djm 313: c->detach_close = 0;
1.165 markus 314: c->confirm = NULL;
1.204 djm 315: c->confirm_ctx = NULL;
1.65 markus 316: c->input_filter = NULL;
1.231 reyk 317: c->output_filter = NULL;
1.25 markus 318: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 319: return c;
1.1 deraadt 320: }
1.52 markus 321:
1.132 markus 322: static int
323: channel_find_maxfd(void)
324: {
1.209 avsm 325: u_int i;
326: int max = 0;
1.132 markus 327: Channel *c;
328:
329: for (i = 0; i < channels_alloc; i++) {
330: c = channels[i];
331: if (c != NULL) {
332: max = MAX(max, c->rfd);
333: max = MAX(max, c->wfd);
334: max = MAX(max, c->efd);
335: }
336: }
337: return max;
338: }
339:
340: int
341: channel_close_fd(int *fdp)
342: {
343: int ret = 0, fd = *fdp;
344:
345: if (fd != -1) {
346: ret = close(fd);
347: *fdp = -1;
348: if (fd == channel_max_fd)
349: channel_max_fd = channel_find_maxfd();
350: }
351: return ret;
352: }
353:
1.52 markus 354: /* Close all channel fd/socket. */
1.127 itojun 355: static void
1.52 markus 356: channel_close_fds(Channel *c)
357: {
1.204 djm 358: debug3("channel %d: close_fds r %d w %d e %d c %d",
359: c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
1.118 markus 360:
1.132 markus 361: channel_close_fd(&c->sock);
1.204 djm 362: channel_close_fd(&c->ctl_fd);
1.132 markus 363: channel_close_fd(&c->rfd);
364: channel_close_fd(&c->wfd);
365: channel_close_fd(&c->efd);
1.121 markus 366: }
367:
368: /* Free the channel and close its fd/socket. */
369: void
370: channel_free(Channel *c)
371: {
372: char *s;
1.209 avsm 373: u_int i, n;
1.121 markus 374:
375: for (n = 0, i = 0; i < channels_alloc; i++)
376: if (channels[i])
377: n++;
1.209 avsm 378: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 379: c->remote_name ? c->remote_name : "???", n);
380:
381: s = channel_open_message();
1.194 markus 382: debug3("channel %d: status: %s", c->self, s);
1.121 markus 383: xfree(s);
384:
385: if (c->sock != -1)
386: shutdown(c->sock, SHUT_RDWR);
1.204 djm 387: if (c->ctl_fd != -1)
388: shutdown(c->ctl_fd, SHUT_RDWR);
1.121 markus 389: channel_close_fds(c);
390: buffer_free(&c->input);
391: buffer_free(&c->output);
392: buffer_free(&c->extended);
393: if (c->remote_name) {
394: xfree(c->remote_name);
395: c->remote_name = NULL;
396: }
397: channels[c->self] = NULL;
398: xfree(c);
399: }
400:
401: void
1.126 markus 402: channel_free_all(void)
1.121 markus 403: {
1.209 avsm 404: u_int i;
1.121 markus 405:
1.126 markus 406: for (i = 0; i < channels_alloc; i++)
407: if (channels[i] != NULL)
408: channel_free(channels[i]);
1.131 markus 409: }
410:
1.121 markus 411: /*
412: * Closes the sockets/fds of all channels. This is used to close extra file
413: * descriptors after a fork.
414: */
415: void
1.142 itojun 416: channel_close_all(void)
1.121 markus 417: {
1.209 avsm 418: u_int i;
1.121 markus 419:
420: for (i = 0; i < channels_alloc; i++)
421: if (channels[i] != NULL)
422: channel_close_fds(channels[i]);
423: }
424:
425: /*
1.131 markus 426: * Stop listening to channels.
427: */
428: void
429: channel_stop_listening(void)
430: {
1.209 avsm 431: u_int i;
1.131 markus 432: Channel *c;
433:
434: for (i = 0; i < channels_alloc; i++) {
435: c = channels[i];
436: if (c != NULL) {
437: switch (c->type) {
438: case SSH_CHANNEL_AUTH_SOCKET:
439: case SSH_CHANNEL_PORT_LISTENER:
440: case SSH_CHANNEL_RPORT_LISTENER:
441: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 442: channel_close_fd(&c->sock);
1.131 markus 443: channel_free(c);
444: break;
445: }
446: }
447: }
448: }
449:
450: /*
1.121 markus 451: * Returns true if no channel has too much buffered data, and false if one or
452: * more channel is overfull.
453: */
454: int
1.142 itojun 455: channel_not_very_much_buffered_data(void)
1.121 markus 456: {
457: u_int i;
458: Channel *c;
459:
460: for (i = 0; i < channels_alloc; i++) {
461: c = channels[i];
462: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 463: #if 0
464: if (!compat20 &&
465: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 466: debug2("channel %d: big input buffer %d",
1.121 markus 467: c->self, buffer_len(&c->input));
468: return 0;
469: }
1.136 markus 470: #endif
1.121 markus 471: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 472: debug2("channel %d: big output buffer %u > %u",
1.136 markus 473: c->self, buffer_len(&c->output),
474: packet_get_maxsize());
1.121 markus 475: return 0;
476: }
477: }
478: }
479: return 1;
480: }
481:
482: /* Returns true if any channel is still open. */
483: int
1.142 itojun 484: channel_still_open(void)
1.121 markus 485: {
1.209 avsm 486: u_int i;
1.121 markus 487: Channel *c;
488:
489: for (i = 0; i < channels_alloc; i++) {
490: c = channels[i];
491: if (c == NULL)
492: continue;
493: switch (c->type) {
494: case SSH_CHANNEL_X11_LISTENER:
495: case SSH_CHANNEL_PORT_LISTENER:
496: case SSH_CHANNEL_RPORT_LISTENER:
497: case SSH_CHANNEL_CLOSED:
498: case SSH_CHANNEL_AUTH_SOCKET:
499: case SSH_CHANNEL_DYNAMIC:
500: case SSH_CHANNEL_CONNECTING:
501: case SSH_CHANNEL_ZOMBIE:
502: continue;
503: case SSH_CHANNEL_LARVAL:
504: if (!compat20)
505: fatal("cannot happen: SSH_CHANNEL_LARVAL");
506: continue;
507: case SSH_CHANNEL_OPENING:
508: case SSH_CHANNEL_OPEN:
509: case SSH_CHANNEL_X11_OPEN:
510: return 1;
511: case SSH_CHANNEL_INPUT_DRAINING:
512: case SSH_CHANNEL_OUTPUT_DRAINING:
513: if (!compat13)
514: fatal("cannot happen: OUT_DRAIN");
515: return 1;
516: default:
517: fatal("channel_still_open: bad channel type %d", c->type);
518: /* NOTREACHED */
519: }
520: }
521: return 0;
522: }
523:
524: /* Returns the id of an open channel suitable for keepaliving */
525: int
1.142 itojun 526: channel_find_open(void)
1.121 markus 527: {
1.209 avsm 528: u_int i;
1.121 markus 529: Channel *c;
530:
531: for (i = 0; i < channels_alloc; i++) {
532: c = channels[i];
1.206 djm 533: if (c == NULL || c->remote_id < 0)
1.121 markus 534: continue;
535: switch (c->type) {
536: case SSH_CHANNEL_CLOSED:
537: case SSH_CHANNEL_DYNAMIC:
538: case SSH_CHANNEL_X11_LISTENER:
539: case SSH_CHANNEL_PORT_LISTENER:
540: case SSH_CHANNEL_RPORT_LISTENER:
541: case SSH_CHANNEL_OPENING:
542: case SSH_CHANNEL_CONNECTING:
543: case SSH_CHANNEL_ZOMBIE:
544: continue;
545: case SSH_CHANNEL_LARVAL:
546: case SSH_CHANNEL_AUTH_SOCKET:
547: case SSH_CHANNEL_OPEN:
548: case SSH_CHANNEL_X11_OPEN:
549: return i;
550: case SSH_CHANNEL_INPUT_DRAINING:
551: case SSH_CHANNEL_OUTPUT_DRAINING:
552: if (!compat13)
553: fatal("cannot happen: OUT_DRAIN");
554: return i;
555: default:
556: fatal("channel_find_open: bad channel type %d", c->type);
557: /* NOTREACHED */
558: }
559: }
560: return -1;
561: }
562:
563:
564: /*
565: * Returns a message describing the currently open forwarded connections,
566: * suitable for sending to the client. The message contains crlf pairs for
567: * newlines.
568: */
569: char *
1.142 itojun 570: channel_open_message(void)
1.121 markus 571: {
572: Buffer buffer;
573: Channel *c;
574: char buf[1024], *cp;
1.209 avsm 575: u_int i;
1.121 markus 576:
577: buffer_init(&buffer);
578: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
579: buffer_append(&buffer, buf, strlen(buf));
580: for (i = 0; i < channels_alloc; i++) {
581: c = channels[i];
582: if (c == NULL)
583: continue;
584: switch (c->type) {
585: case SSH_CHANNEL_X11_LISTENER:
586: case SSH_CHANNEL_PORT_LISTENER:
587: case SSH_CHANNEL_RPORT_LISTENER:
588: case SSH_CHANNEL_CLOSED:
589: case SSH_CHANNEL_AUTH_SOCKET:
590: case SSH_CHANNEL_ZOMBIE:
591: continue;
592: case SSH_CHANNEL_LARVAL:
593: case SSH_CHANNEL_OPENING:
594: case SSH_CHANNEL_CONNECTING:
595: case SSH_CHANNEL_DYNAMIC:
596: case SSH_CHANNEL_OPEN:
597: case SSH_CHANNEL_X11_OPEN:
598: case SSH_CHANNEL_INPUT_DRAINING:
599: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 600: snprintf(buf, sizeof buf,
601: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
1.121 markus 602: c->self, c->remote_name,
603: c->type, c->remote_id,
604: c->istate, buffer_len(&c->input),
605: c->ostate, buffer_len(&c->output),
1.204 djm 606: c->rfd, c->wfd, c->ctl_fd);
1.121 markus 607: buffer_append(&buffer, buf, strlen(buf));
608: continue;
609: default:
610: fatal("channel_open_message: bad channel type %d", c->type);
611: /* NOTREACHED */
612: }
613: }
614: buffer_append(&buffer, "\0", 1);
615: cp = xstrdup(buffer_ptr(&buffer));
616: buffer_free(&buffer);
617: return cp;
618: }
619:
620: void
621: channel_send_open(int id)
622: {
623: Channel *c = channel_lookup(id);
1.180 deraadt 624:
1.121 markus 625: if (c == NULL) {
1.188 itojun 626: logit("channel_send_open: %d: bad id", id);
1.121 markus 627: return;
628: }
1.184 markus 629: debug2("channel %d: send open", id);
1.121 markus 630: packet_start(SSH2_MSG_CHANNEL_OPEN);
631: packet_put_cstring(c->ctype);
632: packet_put_int(c->self);
633: packet_put_int(c->local_window);
634: packet_put_int(c->local_maxpacket);
635: packet_send();
636: }
637:
638: void
1.184 markus 639: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 640: {
1.184 markus 641: Channel *c = channel_lookup(id);
1.180 deraadt 642:
1.121 markus 643: if (c == NULL) {
1.188 itojun 644: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 645: return;
646: }
1.204 djm 647: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 648: packet_start(SSH2_MSG_CHANNEL_REQUEST);
649: packet_put_int(c->remote_id);
650: packet_put_cstring(service);
651: packet_put_char(wantconfirm);
652: }
1.241 deraadt 653:
1.121 markus 654: void
1.204 djm 655: channel_register_confirm(int id, channel_callback_fn *fn, void *ctx)
1.121 markus 656: {
657: Channel *c = channel_lookup(id);
1.180 deraadt 658:
1.121 markus 659: if (c == NULL) {
1.188 itojun 660: logit("channel_register_comfirm: %d: bad id", id);
1.121 markus 661: return;
662: }
1.165 markus 663: c->confirm = fn;
1.204 djm 664: c->confirm_ctx = ctx;
1.121 markus 665: }
1.241 deraadt 666:
1.121 markus 667: void
1.225 djm 668: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 669: {
1.229 markus 670: Channel *c = channel_by_id(id);
1.180 deraadt 671:
1.121 markus 672: if (c == NULL) {
1.188 itojun 673: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 674: return;
675: }
1.131 markus 676: c->detach_user = fn;
1.225 djm 677: c->detach_close = do_close;
1.121 markus 678: }
1.241 deraadt 679:
1.121 markus 680: void
681: channel_cancel_cleanup(int id)
682: {
1.229 markus 683: Channel *c = channel_by_id(id);
1.180 deraadt 684:
1.121 markus 685: if (c == NULL) {
1.188 itojun 686: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 687: return;
1.52 markus 688: }
1.131 markus 689: c->detach_user = NULL;
1.225 djm 690: c->detach_close = 0;
1.121 markus 691: }
1.241 deraadt 692:
1.121 markus 693: void
1.231 reyk 694: channel_register_filter(int id, channel_infilter_fn *ifn,
695: channel_outfilter_fn *ofn)
1.121 markus 696: {
697: Channel *c = channel_lookup(id);
1.180 deraadt 698:
1.121 markus 699: if (c == NULL) {
1.188 itojun 700: logit("channel_register_filter: %d: bad id", id);
1.121 markus 701: return;
1.52 markus 702: }
1.231 reyk 703: c->input_filter = ifn;
704: c->output_filter = ofn;
1.52 markus 705: }
706:
1.49 markus 707: void
1.121 markus 708: channel_set_fds(int id, int rfd, int wfd, int efd,
1.168 markus 709: int extusage, int nonblock, u_int window_max)
1.1 deraadt 710: {
1.121 markus 711: Channel *c = channel_lookup(id);
1.180 deraadt 712:
1.121 markus 713: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
714: fatal("channel_activate for non-larval channel %d.", id);
715: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
716: c->type = SSH_CHANNEL_OPEN;
1.168 markus 717: c->local_window = c->local_window_max = window_max;
1.121 markus 718: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
719: packet_put_int(c->remote_id);
720: packet_put_int(c->local_window);
721: packet_send();
1.1 deraadt 722: }
723:
1.27 markus 724: /*
1.41 markus 725: * 'channel_pre*' are called just before select() to add any bits relevant to
726: * channels in the select bitmasks.
727: */
728: /*
729: * 'channel_post*': perform any appropriate operations for channels which
730: * have events pending.
1.27 markus 731: */
1.237 deraadt 732: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 733: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
734: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
735:
1.127 itojun 736: static void
1.237 deraadt 737: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 738: {
739: FD_SET(c->sock, readset);
740: }
741:
1.127 itojun 742: static void
1.237 deraadt 743: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 744: {
745: debug3("channel %d: waiting for connection", c->self);
746: FD_SET(c->sock, writeset);
747: }
748:
1.127 itojun 749: static void
1.237 deraadt 750: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 751: {
752: if (buffer_len(&c->input) < packet_get_maxsize())
753: FD_SET(c->sock, readset);
754: if (buffer_len(&c->output) > 0)
755: FD_SET(c->sock, writeset);
756: }
1.1 deraadt 757:
1.127 itojun 758: static void
1.237 deraadt 759: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 760: {
1.157 markus 761: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 762:
1.44 markus 763: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 764: limit > 0 &&
1.250 djm 765: buffer_len(&c->input) < limit &&
766: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 767: FD_SET(c->rfd, readset);
768: if (c->ostate == CHAN_OUTPUT_OPEN ||
769: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
770: if (buffer_len(&c->output) > 0) {
771: FD_SET(c->wfd, writeset);
772: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 773: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 774: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
775: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 776: else
777: chan_obuf_empty(c);
1.44 markus 778: }
779: }
780: /** XXX check close conditions, too */
1.157 markus 781: if (compat20 && c->efd != -1) {
1.44 markus 782: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
783: buffer_len(&c->extended) > 0)
784: FD_SET(c->efd, writeset);
1.172 markus 785: else if (!(c->flags & CHAN_EOF_SENT) &&
786: c->extended_usage == CHAN_EXTENDED_READ &&
1.44 markus 787: buffer_len(&c->extended) < c->remote_window)
788: FD_SET(c->efd, readset);
789: }
1.204 djm 790: /* XXX: What about efd? races? */
1.208 deraadt 791: if (compat20 && c->ctl_fd != -1 &&
1.204 djm 792: c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
793: FD_SET(c->ctl_fd, readset);
1.44 markus 794: }
795:
1.127 itojun 796: static void
1.237 deraadt 797: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 798: {
799: if (buffer_len(&c->input) == 0) {
800: packet_start(SSH_MSG_CHANNEL_CLOSE);
801: packet_put_int(c->remote_id);
802: packet_send();
803: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 804: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 805: }
806: }
807:
1.127 itojun 808: static void
1.237 deraadt 809: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 810: {
811: if (buffer_len(&c->output) == 0)
1.113 markus 812: chan_mark_dead(c);
1.49 markus 813: else
1.41 markus 814: FD_SET(c->sock, writeset);
815: }
816:
817: /*
818: * This is a special state for X11 authentication spoofing. An opened X11
819: * connection (when authentication spoofing is being done) remains in this
820: * state until the first packet has been completely read. The authentication
821: * data in that packet is then substituted by the real data if it matches the
822: * fake data, and the channel is put into normal mode.
1.51 markus 823: * XXX All this happens at the client side.
1.121 markus 824: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 825: */
1.127 itojun 826: static int
1.121 markus 827: x11_open_helper(Buffer *b)
1.1 deraadt 828: {
1.77 markus 829: u_char *ucp;
830: u_int proto_len, data_len;
1.25 markus 831:
1.41 markus 832: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 833: if (buffer_len(b) < 12)
1.41 markus 834: return 0;
835:
836: /* Parse the lengths of variable-length fields. */
1.155 stevesk 837: ucp = buffer_ptr(b);
1.41 markus 838: if (ucp[0] == 0x42) { /* Byte order MSB first. */
839: proto_len = 256 * ucp[6] + ucp[7];
840: data_len = 256 * ucp[8] + ucp[9];
841: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
842: proto_len = ucp[6] + 256 * ucp[7];
843: data_len = ucp[8] + 256 * ucp[9];
844: } else {
1.194 markus 845: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 846: ucp[0]);
1.41 markus 847: return -1;
848: }
849:
850: /* Check if the whole packet is in buffer. */
1.121 markus 851: if (buffer_len(b) <
1.41 markus 852: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
853: return 0;
854:
855: /* Check if authentication protocol matches. */
856: if (proto_len != strlen(x11_saved_proto) ||
857: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 858: debug2("X11 connection uses different authentication protocol.");
1.41 markus 859: return -1;
860: }
861: /* Check if authentication data matches our fake data. */
862: if (data_len != x11_fake_data_len ||
863: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
864: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 865: debug2("X11 auth data does not match fake data.");
1.41 markus 866: return -1;
867: }
868: /* Check fake data length */
869: if (x11_fake_data_len != x11_saved_data_len) {
870: error("X11 fake_data_len %d != saved_data_len %d",
871: x11_fake_data_len, x11_saved_data_len);
872: return -1;
873: }
874: /*
875: * Received authentication protocol and data match
876: * our fake data. Substitute the fake data with real
877: * data.
878: */
879: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
880: x11_saved_data, x11_saved_data_len);
881: return 1;
882: }
883:
1.127 itojun 884: static void
1.237 deraadt 885: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 886: {
1.121 markus 887: int ret = x11_open_helper(&c->output);
1.180 deraadt 888:
1.41 markus 889: if (ret == 1) {
890: /* Start normal processing for the channel. */
891: c->type = SSH_CHANNEL_OPEN;
1.47 markus 892: channel_pre_open_13(c, readset, writeset);
1.41 markus 893: } else if (ret == -1) {
894: /*
895: * We have received an X11 connection that has bad
896: * authentication information.
897: */
1.188 itojun 898: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 899: buffer_clear(&c->input);
900: buffer_clear(&c->output);
1.132 markus 901: channel_close_fd(&c->sock);
1.41 markus 902: c->sock = -1;
903: c->type = SSH_CHANNEL_CLOSED;
904: packet_start(SSH_MSG_CHANNEL_CLOSE);
905: packet_put_int(c->remote_id);
906: packet_send();
907: }
908: }
1.25 markus 909:
1.127 itojun 910: static void
1.237 deraadt 911: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 912: {
1.121 markus 913: int ret = x11_open_helper(&c->output);
1.133 markus 914:
915: /* c->force_drain = 1; */
916:
1.41 markus 917: if (ret == 1) {
918: c->type = SSH_CHANNEL_OPEN;
1.157 markus 919: channel_pre_open(c, readset, writeset);
1.41 markus 920: } else if (ret == -1) {
1.188 itojun 921: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 922: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 923: chan_read_failed(c);
924: buffer_clear(&c->input);
925: chan_ibuf_empty(c);
926: buffer_clear(&c->output);
927: /* for proto v1, the peer will send an IEOF */
928: if (compat20)
929: chan_write_failed(c);
930: else
931: c->type = SSH_CHANNEL_OPEN;
1.194 markus 932: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 933: }
934: }
1.25 markus 935:
1.104 markus 936: /* try to decode a socks4 header */
1.127 itojun 937: static int
1.237 deraadt 938: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 939: {
1.181 markus 940: char *p, *host;
1.217 djm 941: u_int len, have, i, found;
1.148 deraadt 942: char username[256];
1.103 markus 943: struct {
944: u_int8_t version;
945: u_int8_t command;
946: u_int16_t dest_port;
1.104 markus 947: struct in_addr dest_addr;
1.103 markus 948: } s4_req, s4_rsp;
949:
1.104 markus 950: debug2("channel %d: decode socks4", c->self);
1.109 markus 951:
952: have = buffer_len(&c->input);
953: len = sizeof(s4_req);
954: if (have < len)
955: return 0;
956: p = buffer_ptr(&c->input);
957: for (found = 0, i = len; i < have; i++) {
958: if (p[i] == '\0') {
959: found = 1;
960: break;
961: }
962: if (i > 1024) {
963: /* the peer is probably sending garbage */
964: debug("channel %d: decode socks4: too long",
965: c->self);
966: return -1;
967: }
968: }
969: if (!found)
970: return 0;
1.103 markus 971: buffer_get(&c->input, (char *)&s4_req.version, 1);
972: buffer_get(&c->input, (char *)&s4_req.command, 1);
973: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 974: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 975: have = buffer_len(&c->input);
1.103 markus 976: p = buffer_ptr(&c->input);
977: len = strlen(p);
1.106 markus 978: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 979: if (len > have)
1.104 markus 980: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 981: c->self, len, have);
982: strlcpy(username, p, sizeof(username));
983: buffer_consume(&c->input, len);
984: buffer_consume(&c->input, 1); /* trailing '\0' */
985:
1.104 markus 986: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 987: strlcpy(c->path, host, sizeof(c->path));
988: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 989:
1.194 markus 990: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.106 markus 991: c->self, host, c->host_port, s4_req.command);
1.103 markus 992:
1.104 markus 993: if (s4_req.command != 1) {
994: debug("channel %d: cannot handle: socks4 cn %d",
995: c->self, s4_req.command);
996: return -1;
1.103 markus 997: }
1.104 markus 998: s4_rsp.version = 0; /* vn: 0 for reply */
999: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1000: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1001: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1002: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1003: return 1;
1004: }
1005:
1.193 markus 1006: /* try to decode a socks5 header */
1007: #define SSH_SOCKS5_AUTHDONE 0x1000
1008: #define SSH_SOCKS5_NOAUTH 0x00
1009: #define SSH_SOCKS5_IPV4 0x01
1010: #define SSH_SOCKS5_DOMAIN 0x03
1011: #define SSH_SOCKS5_IPV6 0x04
1012: #define SSH_SOCKS5_CONNECT 0x01
1013: #define SSH_SOCKS5_SUCCESS 0x00
1014:
1015: static int
1.237 deraadt 1016: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1017: {
1018: struct {
1019: u_int8_t version;
1020: u_int8_t command;
1021: u_int8_t reserved;
1022: u_int8_t atyp;
1023: } s5_req, s5_rsp;
1024: u_int16_t dest_port;
1025: u_char *p, dest_addr[255+1];
1.252 djm 1026: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1027:
1028: debug2("channel %d: decode socks5", c->self);
1029: p = buffer_ptr(&c->input);
1030: if (p[0] != 0x05)
1031: return -1;
1032: have = buffer_len(&c->input);
1033: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1034: /* format: ver | nmethods | methods */
1.198 djm 1035: if (have < 2)
1.193 markus 1036: return 0;
1037: nmethods = p[1];
1038: if (have < nmethods + 2)
1039: return 0;
1040: /* look for method: "NO AUTHENTICATION REQUIRED" */
1041: for (found = 0, i = 2 ; i < nmethods + 2; i++) {
1042: if (p[i] == SSH_SOCKS5_NOAUTH ) {
1043: found = 1;
1044: break;
1045: }
1046: }
1047: if (!found) {
1048: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1049: c->self);
1050: return -1;
1051: }
1052: buffer_consume(&c->input, nmethods + 2);
1053: buffer_put_char(&c->output, 0x05); /* version */
1054: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1055: FD_SET(c->sock, writeset);
1056: c->flags |= SSH_SOCKS5_AUTHDONE;
1057: debug2("channel %d: socks5 auth done", c->self);
1058: return 0; /* need more */
1059: }
1060: debug2("channel %d: socks5 post auth", c->self);
1061: if (have < sizeof(s5_req)+1)
1062: return 0; /* need more */
1.247 deraadt 1063: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1064: if (s5_req.version != 0x05 ||
1065: s5_req.command != SSH_SOCKS5_CONNECT ||
1066: s5_req.reserved != 0x00) {
1.194 markus 1067: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1068: return -1;
1069: }
1.213 deraadt 1070: switch (s5_req.atyp){
1.193 markus 1071: case SSH_SOCKS5_IPV4:
1072: addrlen = 4;
1073: af = AF_INET;
1074: break;
1075: case SSH_SOCKS5_DOMAIN:
1076: addrlen = p[sizeof(s5_req)];
1077: af = -1;
1078: break;
1079: case SSH_SOCKS5_IPV6:
1080: addrlen = 16;
1081: af = AF_INET6;
1082: break;
1083: default:
1.194 markus 1084: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1085: return -1;
1086: }
1.252 djm 1087: need = sizeof(s5_req) + addrlen + 2;
1088: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1089: need++;
1090: if (have < need)
1.193 markus 1091: return 0;
1092: buffer_consume(&c->input, sizeof(s5_req));
1093: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1094: buffer_consume(&c->input, 1); /* host string length */
1095: buffer_get(&c->input, (char *)&dest_addr, addrlen);
1096: buffer_get(&c->input, (char *)&dest_port, 2);
1097: dest_addr[addrlen] = '\0';
1098: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1.201 deraadt 1099: strlcpy(c->path, (char *)dest_addr, sizeof(c->path));
1.193 markus 1100: else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL)
1101: return -1;
1102: c->host_port = ntohs(dest_port);
1.198 djm 1103:
1.194 markus 1104: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1105: c->self, c->path, c->host_port, s5_req.command);
1106:
1107: s5_rsp.version = 0x05;
1108: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1109: s5_rsp.reserved = 0; /* ignored */
1110: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1111: ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1112: dest_port = 0; /* ignored */
1113:
1.246 deraadt 1114: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1115: buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1116: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1117: return 1;
1118: }
1119:
1.104 markus 1120: /* dynamic port forwarding */
1.127 itojun 1121: static void
1.237 deraadt 1122: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1123: {
1124: u_char *p;
1.217 djm 1125: u_int have;
1126: int ret;
1.103 markus 1127:
1.104 markus 1128: have = buffer_len(&c->input);
1.137 markus 1129: c->delayed = 0;
1.104 markus 1130: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1131: /* buffer_dump(&c->input); */
1.104 markus 1132: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1133: if (have < 3) {
1.104 markus 1134: /* need more */
1135: FD_SET(c->sock, readset);
1136: return;
1137: }
1138: /* try to guess the protocol */
1139: p = buffer_ptr(&c->input);
1140: switch (p[0]) {
1141: case 0x04:
1142: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1143: break;
1144: case 0x05:
1145: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1146: break;
1147: default:
1148: ret = -1;
1149: break;
1150: }
1151: if (ret < 0) {
1.113 markus 1152: chan_mark_dead(c);
1.104 markus 1153: } else if (ret == 0) {
1154: debug2("channel %d: pre_dynamic: need more", c->self);
1155: /* need more */
1156: FD_SET(c->sock, readset);
1157: } else {
1158: /* switch to the next state */
1159: c->type = SSH_CHANNEL_OPENING;
1160: port_open_helper(c, "direct-tcpip");
1161: }
1.103 markus 1162: }
1163:
1.41 markus 1164: /* This is our fake X11 server socket. */
1.127 itojun 1165: static void
1.237 deraadt 1166: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1167: {
1.113 markus 1168: Channel *nc;
1.41 markus 1169: struct sockaddr addr;
1.162 stevesk 1170: int newsock;
1.41 markus 1171: socklen_t addrlen;
1.85 markus 1172: char buf[16384], *remote_ipaddr;
1.51 markus 1173: int remote_port;
1.25 markus 1174:
1.41 markus 1175: if (FD_ISSET(c->sock, readset)) {
1176: debug("X11 connection requested.");
1177: addrlen = sizeof(addr);
1178: newsock = accept(c->sock, &addr, &addrlen);
1.149 markus 1179: if (c->single_connection) {
1.194 markus 1180: debug2("single_connection: closing X11 listener.");
1.149 markus 1181: channel_close_fd(&c->sock);
1182: chan_mark_dead(c);
1183: }
1.41 markus 1184: if (newsock < 0) {
1185: error("accept: %.100s", strerror(errno));
1186: return;
1187: }
1.162 stevesk 1188: set_nodelay(newsock);
1.85 markus 1189: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1190: remote_port = get_peer_port(newsock);
1.41 markus 1191: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1192: remote_ipaddr, remote_port);
1.51 markus 1193:
1.113 markus 1194: nc = channel_new("accepted x11 socket",
1.51 markus 1195: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1196: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1197: if (compat20) {
1198: packet_start(SSH2_MSG_CHANNEL_OPEN);
1199: packet_put_cstring("x11");
1.113 markus 1200: packet_put_int(nc->self);
1.149 markus 1201: packet_put_int(nc->local_window_max);
1202: packet_put_int(nc->local_maxpacket);
1.85 markus 1203: /* originator ipaddr and port */
1204: packet_put_cstring(remote_ipaddr);
1.57 markus 1205: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1206: debug2("ssh2 x11 bug compat mode");
1.57 markus 1207: } else {
1208: packet_put_int(remote_port);
1209: }
1.51 markus 1210: packet_send();
1211: } else {
1212: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1213: packet_put_int(nc->self);
1.121 markus 1214: if (packet_get_protocol_flags() &
1215: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1216: packet_put_cstring(buf);
1.51 markus 1217: packet_send();
1218: }
1.85 markus 1219: xfree(remote_ipaddr);
1.41 markus 1220: }
1221: }
1.25 markus 1222:
1.127 itojun 1223: static void
1.103 markus 1224: port_open_helper(Channel *c, char *rtype)
1225: {
1226: int direct;
1227: char buf[1024];
1228: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1229: int remote_port = get_peer_port(c->sock);
1.103 markus 1230:
1231: direct = (strcmp(rtype, "direct-tcpip") == 0);
1232:
1233: snprintf(buf, sizeof buf,
1234: "%s: listening port %d for %.100s port %d, "
1235: "connect from %.200s port %d",
1236: rtype, c->listening_port, c->path, c->host_port,
1237: remote_ipaddr, remote_port);
1238:
1239: xfree(c->remote_name);
1240: c->remote_name = xstrdup(buf);
1241:
1242: if (compat20) {
1243: packet_start(SSH2_MSG_CHANNEL_OPEN);
1244: packet_put_cstring(rtype);
1245: packet_put_int(c->self);
1246: packet_put_int(c->local_window_max);
1247: packet_put_int(c->local_maxpacket);
1248: if (direct) {
1249: /* target host, port */
1250: packet_put_cstring(c->path);
1251: packet_put_int(c->host_port);
1252: } else {
1253: /* listen address, port */
1254: packet_put_cstring(c->path);
1255: packet_put_int(c->listening_port);
1256: }
1257: /* originator host and port */
1258: packet_put_cstring(remote_ipaddr);
1.216 markus 1259: packet_put_int((u_int)remote_port);
1.103 markus 1260: packet_send();
1261: } else {
1262: packet_start(SSH_MSG_PORT_OPEN);
1263: packet_put_int(c->self);
1264: packet_put_cstring(c->path);
1265: packet_put_int(c->host_port);
1.121 markus 1266: if (packet_get_protocol_flags() &
1267: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1268: packet_put_cstring(c->remote_name);
1269: packet_send();
1270: }
1271: xfree(remote_ipaddr);
1272: }
1273:
1.226 djm 1274: static void
1275: channel_set_reuseaddr(int fd)
1276: {
1277: int on = 1;
1278:
1279: /*
1280: * Set socket options.
1281: * Allow local port reuse in TIME_WAIT.
1282: */
1283: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1284: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1285: }
1286:
1.41 markus 1287: /*
1288: * This socket is listening for connections to a forwarded TCP/IP port.
1289: */
1.127 itojun 1290: static void
1.237 deraadt 1291: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1292: {
1.103 markus 1293: Channel *nc;
1.41 markus 1294: struct sockaddr addr;
1.113 markus 1295: int newsock, nextstate;
1.41 markus 1296: socklen_t addrlen;
1.103 markus 1297: char *rtype;
1.73 markus 1298:
1.41 markus 1299: if (FD_ISSET(c->sock, readset)) {
1300: debug("Connection to port %d forwarding "
1301: "to %.100s port %d requested.",
1302: c->listening_port, c->path, c->host_port);
1.103 markus 1303:
1.137 markus 1304: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1305: nextstate = SSH_CHANNEL_OPENING;
1306: rtype = "forwarded-tcpip";
1307: } else {
1308: if (c->host_port == 0) {
1309: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1310: rtype = "dynamic-tcpip";
1.137 markus 1311: } else {
1312: nextstate = SSH_CHANNEL_OPENING;
1313: rtype = "direct-tcpip";
1314: }
1315: }
1.103 markus 1316:
1.41 markus 1317: addrlen = sizeof(addr);
1318: newsock = accept(c->sock, &addr, &addrlen);
1319: if (newsock < 0) {
1320: error("accept: %.100s", strerror(errno));
1321: return;
1322: }
1.169 stevesk 1323: set_nodelay(newsock);
1.190 markus 1324: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1325: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1326: nc->listening_port = c->listening_port;
1327: nc->host_port = c->host_port;
1328: strlcpy(nc->path, c->path, sizeof(nc->path));
1329:
1.137 markus 1330: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1331: /*
1332: * do not call the channel_post handler until
1333: * this flag has been reset by a pre-handler.
1334: * otherwise the FD_ISSET calls might overflow
1335: */
1336: nc->delayed = 1;
1337: } else {
1.103 markus 1338: port_open_helper(nc, rtype);
1.137 markus 1339: }
1.41 markus 1340: }
1341: }
1.25 markus 1342:
1.41 markus 1343: /*
1344: * This is the authentication agent socket listening for connections from
1345: * clients.
1346: */
1.127 itojun 1347: static void
1.237 deraadt 1348: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1349: {
1.113 markus 1350: Channel *nc;
1351: int newsock;
1.41 markus 1352: struct sockaddr addr;
1353: socklen_t addrlen;
1.25 markus 1354:
1.41 markus 1355: if (FD_ISSET(c->sock, readset)) {
1356: addrlen = sizeof(addr);
1357: newsock = accept(c->sock, &addr, &addrlen);
1358: if (newsock < 0) {
1359: error("accept from auth socket: %.100s", strerror(errno));
1360: return;
1361: }
1.113 markus 1362: nc = channel_new("accepted auth socket",
1.73 markus 1363: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1364: c->local_window_max, c->local_maxpacket,
1.190 markus 1365: 0, "accepted auth socket", 1);
1.73 markus 1366: if (compat20) {
1367: packet_start(SSH2_MSG_CHANNEL_OPEN);
1368: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1369: packet_put_int(nc->self);
1.73 markus 1370: packet_put_int(c->local_window_max);
1371: packet_put_int(c->local_maxpacket);
1372: } else {
1373: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1374: packet_put_int(nc->self);
1.73 markus 1375: }
1.41 markus 1376: packet_send();
1377: }
1378: }
1.25 markus 1379:
1.127 itojun 1380: static void
1.237 deraadt 1381: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1382: {
1.114 markus 1383: int err = 0;
1.129 stevesk 1384: socklen_t sz = sizeof(err);
1.114 markus 1385:
1.75 markus 1386: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1387: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1388: err = errno;
1389: error("getsockopt SO_ERROR failed");
1390: }
1391: if (err == 0) {
1392: debug("channel %d: connected", c->self);
1393: c->type = SSH_CHANNEL_OPEN;
1394: if (compat20) {
1395: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1396: packet_put_int(c->remote_id);
1397: packet_put_int(c->self);
1398: packet_put_int(c->local_window);
1399: packet_put_int(c->local_maxpacket);
1400: } else {
1401: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1402: packet_put_int(c->remote_id);
1403: packet_put_int(c->self);
1404: }
1.75 markus 1405: } else {
1.114 markus 1406: debug("channel %d: not connected: %s",
1407: c->self, strerror(err));
1408: if (compat20) {
1409: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1410: packet_put_int(c->remote_id);
1411: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1412: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1413: packet_put_cstring(strerror(err));
1414: packet_put_cstring("");
1415: }
1.75 markus 1416: } else {
1.114 markus 1417: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1418: packet_put_int(c->remote_id);
1.75 markus 1419: }
1.114 markus 1420: chan_mark_dead(c);
1.75 markus 1421: }
1.114 markus 1422: packet_send();
1.75 markus 1423: }
1424: }
1425:
1.127 itojun 1426: static int
1.237 deraadt 1427: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1428: {
1.214 markus 1429: char buf[CHAN_RBUF];
1.41 markus 1430: int len;
1.25 markus 1431:
1.118 markus 1432: if (c->rfd != -1 &&
1.41 markus 1433: FD_ISSET(c->rfd, readset)) {
1434: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1435: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1436: return 1;
1.41 markus 1437: if (len <= 0) {
1.194 markus 1438: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1439: c->self, c->rfd, len);
1.104 markus 1440: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1441: debug2("channel %d: not open", c->self);
1.113 markus 1442: chan_mark_dead(c);
1.103 markus 1443: return -1;
1.104 markus 1444: } else if (compat13) {
1.158 markus 1445: buffer_clear(&c->output);
1.41 markus 1446: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1447: debug2("channel %d: input draining.", c->self);
1.25 markus 1448: } else {
1.41 markus 1449: chan_read_failed(c);
1.25 markus 1450: }
1.41 markus 1451: return -1;
1452: }
1.143 deraadt 1453: if (c->input_filter != NULL) {
1.66 markus 1454: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1455: debug2("channel %d: filter stops", c->self);
1.65 markus 1456: chan_read_failed(c);
1457: }
1.228 reyk 1458: } else if (c->datagram) {
1459: buffer_put_string(&c->input, buf, len);
1.65 markus 1460: } else {
1461: buffer_append(&c->input, buf, len);
1462: }
1.41 markus 1463: }
1464: return 1;
1465: }
1.241 deraadt 1466:
1.127 itojun 1467: static int
1.237 deraadt 1468: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1469: {
1.95 markus 1470: struct termios tio;
1.231 reyk 1471: u_char *data = NULL, *buf;
1.134 markus 1472: u_int dlen;
1.41 markus 1473: int len;
1.25 markus 1474:
1.41 markus 1475: /* Send buffered output data to the socket. */
1.118 markus 1476: if (c->wfd != -1 &&
1.41 markus 1477: FD_ISSET(c->wfd, writeset) &&
1478: buffer_len(&c->output) > 0) {
1.231 reyk 1479: if (c->output_filter != NULL) {
1480: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1481: debug2("channel %d: filter stops", c->self);
1.232 reyk 1482: if (c->type != SSH_CHANNEL_OPEN)
1483: chan_mark_dead(c);
1484: else
1485: chan_write_failed(c);
1486: return -1;
1.231 reyk 1487: }
1488: } else if (c->datagram) {
1489: buf = data = buffer_get_string(&c->output, &dlen);
1490: } else {
1491: buf = data = buffer_ptr(&c->output);
1492: dlen = buffer_len(&c->output);
1493: }
1494:
1.228 reyk 1495: if (c->datagram) {
1496: /* ignore truncated writes, datagrams might get lost */
1497: c->local_consumed += dlen + 4;
1.231 reyk 1498: len = write(c->wfd, buf, dlen);
1.228 reyk 1499: xfree(data);
1500: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1501: return 1;
1502: if (len <= 0) {
1503: if (c->type != SSH_CHANNEL_OPEN)
1504: chan_mark_dead(c);
1505: else
1506: chan_write_failed(c);
1507: return -1;
1508: }
1509: return 1;
1510: }
1.231 reyk 1511:
1512: len = write(c->wfd, buf, dlen);
1.53 markus 1513: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1514: return 1;
1.41 markus 1515: if (len <= 0) {
1.104 markus 1516: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1517: debug2("channel %d: not open", c->self);
1.113 markus 1518: chan_mark_dead(c);
1.104 markus 1519: return -1;
1520: } else if (compat13) {
1.158 markus 1521: buffer_clear(&c->output);
1.194 markus 1522: debug2("channel %d: input draining.", c->self);
1.41 markus 1523: c->type = SSH_CHANNEL_INPUT_DRAINING;
1524: } else {
1525: chan_write_failed(c);
1526: }
1527: return -1;
1.91 markus 1528: }
1.231 reyk 1529: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1530: if (tcgetattr(c->wfd, &tio) == 0 &&
1531: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1532: /*
1533: * Simulate echo to reduce the impact of
1.96 markus 1534: * traffic analysis. We need to match the
1.95 markus 1535: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1536: * (4 byte channel id + buf)
1.91 markus 1537: */
1.95 markus 1538: packet_send_ignore(4 + len);
1.91 markus 1539: packet_send();
1540: }
1.25 markus 1541: }
1.41 markus 1542: buffer_consume(&c->output, len);
1.44 markus 1543: if (compat20 && len > 0) {
1544: c->local_consumed += len;
1545: }
1546: }
1547: return 1;
1548: }
1.241 deraadt 1549:
1.127 itojun 1550: static int
1.237 deraadt 1551: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1552: {
1.214 markus 1553: char buf[CHAN_RBUF];
1.44 markus 1554: int len;
1555:
1.45 markus 1556: /** XXX handle drain efd, too */
1.44 markus 1557: if (c->efd != -1) {
1558: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1559: FD_ISSET(c->efd, writeset) &&
1560: buffer_len(&c->extended) > 0) {
1561: len = write(c->efd, buffer_ptr(&c->extended),
1562: buffer_len(&c->extended));
1.70 markus 1563: debug2("channel %d: written %d to efd %d",
1.44 markus 1564: c->self, len, c->efd);
1.93 markus 1565: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1566: return 1;
1567: if (len <= 0) {
1568: debug2("channel %d: closing write-efd %d",
1569: c->self, c->efd);
1.132 markus 1570: channel_close_fd(&c->efd);
1.93 markus 1571: } else {
1.44 markus 1572: buffer_consume(&c->extended, len);
1573: c->local_consumed += len;
1574: }
1575: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1576: FD_ISSET(c->efd, readset)) {
1577: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1578: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1579: c->self, len, c->efd);
1.93 markus 1580: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1581: return 1;
1582: if (len <= 0) {
1583: debug2("channel %d: closing read-efd %d",
1.45 markus 1584: c->self, c->efd);
1.132 markus 1585: channel_close_fd(&c->efd);
1.93 markus 1586: } else {
1.44 markus 1587: buffer_append(&c->extended, buf, len);
1.93 markus 1588: }
1.44 markus 1589: }
1590: }
1591: return 1;
1592: }
1.241 deraadt 1593:
1.127 itojun 1594: static int
1.237 deraadt 1595: channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
1.204 djm 1596: {
1597: char buf[16];
1598: int len;
1599:
1600: /* Monitor control fd to detect if the slave client exits */
1601: if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1602: len = read(c->ctl_fd, buf, sizeof(buf));
1603: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1604: return 1;
1605: if (len <= 0) {
1606: debug2("channel %d: ctl read<=0", c->self);
1607: if (c->type != SSH_CHANNEL_OPEN) {
1608: debug2("channel %d: not open", c->self);
1609: chan_mark_dead(c);
1610: return -1;
1611: } else {
1612: chan_read_failed(c);
1613: chan_write_failed(c);
1614: }
1615: return -1;
1616: } else
1617: fatal("%s: unexpected data on ctl fd", __func__);
1618: }
1619: return 1;
1620: }
1.241 deraadt 1621:
1.204 djm 1622: static int
1.93 markus 1623: channel_check_window(Channel *c)
1.44 markus 1624: {
1.104 markus 1625: if (c->type == SSH_CHANNEL_OPEN &&
1626: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.44 markus 1627: c->local_window < c->local_window_max/2 &&
1628: c->local_consumed > 0) {
1629: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1630: packet_put_int(c->remote_id);
1631: packet_put_int(c->local_consumed);
1632: packet_send();
1.70 markus 1633: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1634: c->self, c->local_window,
1635: c->local_consumed);
1636: c->local_window += c->local_consumed;
1637: c->local_consumed = 0;
1.1 deraadt 1638: }
1.41 markus 1639: return 1;
1.1 deraadt 1640: }
1641:
1.127 itojun 1642: static void
1.237 deraadt 1643: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1644: {
1.137 markus 1645: if (c->delayed)
1646: return;
1.41 markus 1647: channel_handle_rfd(c, readset, writeset);
1648: channel_handle_wfd(c, readset, writeset);
1.157 markus 1649: if (!compat20)
1.137 markus 1650: return;
1.44 markus 1651: channel_handle_efd(c, readset, writeset);
1.204 djm 1652: channel_handle_ctl(c, readset, writeset);
1.93 markus 1653: channel_check_window(c);
1.44 markus 1654: }
1655:
1.127 itojun 1656: static void
1.237 deraadt 1657: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1658: {
1.41 markus 1659: int len;
1.180 deraadt 1660:
1.41 markus 1661: /* Send buffered output data to the socket. */
1662: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1663: len = write(c->sock, buffer_ptr(&c->output),
1664: buffer_len(&c->output));
1665: if (len <= 0)
1.158 markus 1666: buffer_clear(&c->output);
1.41 markus 1667: else
1668: buffer_consume(&c->output, len);
1669: }
1670: }
1.25 markus 1671:
1.127 itojun 1672: static void
1.44 markus 1673: channel_handler_init_20(void)
1674: {
1.157 markus 1675: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1676: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1677: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1678: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1679: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1680: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1681: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1682: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1683:
1.157 markus 1684: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1685: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1686: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1687: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1688: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1689: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1690: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1691: }
1692:
1.127 itojun 1693: static void
1.41 markus 1694: channel_handler_init_13(void)
1695: {
1696: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1697: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1698: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1699: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1700: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1701: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1702: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1703: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1704: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1705:
1.157 markus 1706: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1707: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1708: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1709: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1710: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1711: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1712: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1713: }
1.25 markus 1714:
1.127 itojun 1715: static void
1.41 markus 1716: channel_handler_init_15(void)
1717: {
1.157 markus 1718: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1719: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1720: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1721: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1722: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1723: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1724: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1725:
1.41 markus 1726: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1727: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1728: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1729: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1730: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1731: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1732: }
1.27 markus 1733:
1.127 itojun 1734: static void
1.41 markus 1735: channel_handler_init(void)
1736: {
1737: int i;
1.180 deraadt 1738:
1.148 deraadt 1739: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1740: channel_pre[i] = NULL;
1741: channel_post[i] = NULL;
1742: }
1.44 markus 1743: if (compat20)
1744: channel_handler_init_20();
1745: else if (compat13)
1.41 markus 1746: channel_handler_init_13();
1747: else
1748: channel_handler_init_15();
1749: }
1.25 markus 1750:
1.140 markus 1751: /* gc dead channels */
1752: static void
1753: channel_garbage_collect(Channel *c)
1754: {
1755: if (c == NULL)
1756: return;
1757: if (c->detach_user != NULL) {
1.225 djm 1758: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1759: return;
1.194 markus 1760: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1761: c->detach_user(c->self, NULL);
1762: /* if we still have a callback */
1763: if (c->detach_user != NULL)
1764: return;
1.194 markus 1765: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1766: }
1767: if (!chan_is_dead(c, 1))
1768: return;
1.194 markus 1769: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1770: channel_free(c);
1771: }
1772:
1.127 itojun 1773: static void
1.237 deraadt 1774: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
1.41 markus 1775: {
1776: static int did_init = 0;
1.209 avsm 1777: u_int i;
1.41 markus 1778: Channel *c;
1.25 markus 1779:
1.41 markus 1780: if (!did_init) {
1781: channel_handler_init();
1782: did_init = 1;
1783: }
1784: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1785: c = channels[i];
1786: if (c == NULL)
1.41 markus 1787: continue;
1.118 markus 1788: if (ftab[c->type] != NULL)
1789: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1790: channel_garbage_collect(c);
1.1 deraadt 1791: }
1792: }
1793:
1.121 markus 1794: /*
1795: * Allocate/update select bitmasks and add any bits relevant to channels in
1796: * select bitmasks.
1797: */
1.49 markus 1798: void
1.100 markus 1799: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.209 avsm 1800: u_int *nallocp, int rekeying)
1.41 markus 1801: {
1.243 djm 1802: u_int n, sz, nfdset;
1.84 markus 1803:
1804: n = MAX(*maxfdp, channel_max_fd);
1805:
1.243 djm 1806: nfdset = howmany(n+1, NFDBITS);
1807: /* Explicitly test here, because xrealloc isn't always called */
1808: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1809: fatal("channel_prepare_select: max_fd (%d) is too large", n);
1810: sz = nfdset * sizeof(fd_mask);
1811:
1.132 markus 1812: /* perhaps check sz < nalloc/2 and shrink? */
1813: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 1814: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1815: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 1816: *nallocp = sz;
1.84 markus 1817: }
1.132 markus 1818: *maxfdp = n;
1.84 markus 1819: memset(*readsetp, 0, sz);
1820: memset(*writesetp, 0, sz);
1821:
1.100 markus 1822: if (!rekeying)
1823: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1824: }
1825:
1.121 markus 1826: /*
1827: * After select, perform any appropriate operations for channels which have
1828: * events pending.
1829: */
1.49 markus 1830: void
1.237 deraadt 1831: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 1832: {
1833: channel_handler(channel_post, readset, writeset);
1834: }
1835:
1.121 markus 1836:
1.84 markus 1837: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 1838: void
1.142 itojun 1839: channel_output_poll(void)
1.1 deraadt 1840: {
1.41 markus 1841: Channel *c;
1.209 avsm 1842: u_int i, len;
1.1 deraadt 1843:
1.25 markus 1844: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1845: c = channels[i];
1846: if (c == NULL)
1847: continue;
1.37 markus 1848:
1.121 markus 1849: /*
1850: * We are only interested in channels that can have buffered
1851: * incoming data.
1852: */
1.37 markus 1853: if (compat13) {
1.41 markus 1854: if (c->type != SSH_CHANNEL_OPEN &&
1855: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1856: continue;
1857: } else {
1.41 markus 1858: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1859: continue;
1860: }
1.46 markus 1861: if (compat20 &&
1862: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1863: /* XXX is this true? */
1.140 markus 1864: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1865: continue;
1866: }
1.25 markus 1867:
1868: /* Get the amount of buffered data for this channel. */
1.93 markus 1869: if ((c->istate == CHAN_INPUT_OPEN ||
1870: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1871: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 1872: if (c->datagram) {
1873: if (len > 0) {
1874: u_char *data;
1875: u_int dlen;
1876:
1877: data = buffer_get_string(&c->input,
1878: &dlen);
1879: packet_start(SSH2_MSG_CHANNEL_DATA);
1880: packet_put_int(c->remote_id);
1881: packet_put_string(data, dlen);
1882: packet_send();
1883: c->remote_window -= dlen + 4;
1884: xfree(data);
1885: }
1886: continue;
1887: }
1.121 markus 1888: /*
1889: * Send some data for the other side over the secure
1890: * connection.
1891: */
1.44 markus 1892: if (compat20) {
1893: if (len > c->remote_window)
1894: len = c->remote_window;
1895: if (len > c->remote_maxpacket)
1896: len = c->remote_maxpacket;
1.25 markus 1897: } else {
1.44 markus 1898: if (packet_is_interactive()) {
1899: if (len > 1024)
1900: len = 512;
1901: } else {
1902: /* Keep the packets at reasonable size. */
1903: if (len > packet_get_maxsize()/2)
1904: len = packet_get_maxsize()/2;
1905: }
1.25 markus 1906: }
1.41 markus 1907: if (len > 0) {
1.44 markus 1908: packet_start(compat20 ?
1909: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1910: packet_put_int(c->remote_id);
1911: packet_put_string(buffer_ptr(&c->input), len);
1912: packet_send();
1913: buffer_consume(&c->input, len);
1914: c->remote_window -= len;
1915: }
1916: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1917: if (compat13)
1918: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1919: /*
1920: * input-buffer is empty and read-socket shutdown:
1.172 markus 1921: * tell peer, that we will not send more data: send IEOF.
1922: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 1923: */
1.172 markus 1924: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 1925: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
1926: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 1927: else
1928: chan_ibuf_empty(c);
1.25 markus 1929: }
1.44 markus 1930: /* Send extended data, i.e. stderr */
1931: if (compat20 &&
1.172 markus 1932: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 1933: c->remote_window > 0 &&
1934: (len = buffer_len(&c->extended)) > 0 &&
1935: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 1936: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 1937: c->self, c->remote_window, buffer_len(&c->extended),
1938: c->extended_usage);
1.44 markus 1939: if (len > c->remote_window)
1940: len = c->remote_window;
1941: if (len > c->remote_maxpacket)
1942: len = c->remote_maxpacket;
1943: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1944: packet_put_int(c->remote_id);
1945: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1946: packet_put_string(buffer_ptr(&c->extended), len);
1947: packet_send();
1948: buffer_consume(&c->extended, len);
1949: c->remote_window -= len;
1.93 markus 1950: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1951: }
1.25 markus 1952: }
1.1 deraadt 1953: }
1954:
1.121 markus 1955:
1956: /* -- protocol input */
1.249 djm 1957:
1958: /* ARGSUSED */
1.49 markus 1959: void
1.154 markus 1960: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1961: {
1.37 markus 1962: int id;
1.25 markus 1963: char *data;
1.77 markus 1964: u_int data_len;
1.41 markus 1965: Channel *c;
1.25 markus 1966:
1967: /* Get the channel number and verify it. */
1.37 markus 1968: id = packet_get_int();
1.41 markus 1969: c = channel_lookup(id);
1970: if (c == NULL)
1.37 markus 1971: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 1972:
1973: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 1974: if (c->type != SSH_CHANNEL_OPEN &&
1975: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 1976: return;
1977:
1.25 markus 1978: /* Get the data. */
1979: data = packet_get_string(&data_len);
1.200 markus 1980:
1981: /*
1982: * Ignore data for protocol > 1.3 if output end is no longer open.
1983: * For protocol 2 the sending side is reducing its window as it sends
1984: * data, so we must 'fake' consumption of the data in order to ensure
1985: * that window updates are sent back. Otherwise the connection might
1986: * deadlock.
1987: */
1988: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
1989: if (compat20) {
1990: c->local_window -= data_len;
1991: c->local_consumed += data_len;
1992: }
1993: xfree(data);
1994: return;
1995: }
1.41 markus 1996:
1.143 deraadt 1997: if (compat20) {
1.44 markus 1998: if (data_len > c->local_maxpacket) {
1.188 itojun 1999: logit("channel %d: rcvd big packet %d, maxpack %d",
1.44 markus 2000: c->self, data_len, c->local_maxpacket);
2001: }
2002: if (data_len > c->local_window) {
1.188 itojun 2003: logit("channel %d: rcvd too much data %d, win %d",
1.44 markus 2004: c->self, data_len, c->local_window);
2005: xfree(data);
2006: return;
2007: }
2008: c->local_window -= data_len;
2009: }
1.152 markus 2010: packet_check_eom();
1.228 reyk 2011: if (c->datagram)
2012: buffer_put_string(&c->output, data, data_len);
2013: else
2014: buffer_append(&c->output, data, data_len);
1.25 markus 2015: xfree(data);
1.1 deraadt 2016: }
1.121 markus 2017:
1.249 djm 2018: /* ARGSUSED */
1.49 markus 2019: void
1.154 markus 2020: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2021: {
2022: int id;
2023: char *data;
1.177 markus 2024: u_int data_len, tcode;
1.44 markus 2025: Channel *c;
2026:
2027: /* Get the channel number and verify it. */
2028: id = packet_get_int();
2029: c = channel_lookup(id);
2030:
2031: if (c == NULL)
2032: packet_disconnect("Received extended_data for bad channel %d.", id);
2033: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2034: logit("channel %d: ext data for non open", id);
1.44 markus 2035: return;
1.172 markus 2036: }
2037: if (c->flags & CHAN_EOF_RCVD) {
2038: if (datafellows & SSH_BUG_EXTEOF)
2039: debug("channel %d: accepting ext data after eof", id);
2040: else
2041: packet_disconnect("Received extended_data after EOF "
2042: "on channel %d.", id);
1.44 markus 2043: }
2044: tcode = packet_get_int();
2045: if (c->efd == -1 ||
2046: c->extended_usage != CHAN_EXTENDED_WRITE ||
2047: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2048: logit("channel %d: bad ext data", c->self);
1.44 markus 2049: return;
2050: }
2051: data = packet_get_string(&data_len);
1.152 markus 2052: packet_check_eom();
1.44 markus 2053: if (data_len > c->local_window) {
1.188 itojun 2054: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2055: c->self, data_len, c->local_window);
2056: xfree(data);
2057: return;
2058: }
1.70 markus 2059: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2060: c->local_window -= data_len;
2061: buffer_append(&c->extended, data, data_len);
2062: xfree(data);
2063: }
2064:
1.249 djm 2065: /* ARGSUSED */
1.49 markus 2066: void
1.154 markus 2067: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2068: {
2069: int id;
2070: Channel *c;
2071:
2072: id = packet_get_int();
1.152 markus 2073: packet_check_eom();
1.41 markus 2074: c = channel_lookup(id);
2075: if (c == NULL)
2076: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2077: chan_rcvd_ieof(c);
1.133 markus 2078:
2079: /* XXX force input close */
1.156 markus 2080: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2081: debug("channel %d: FORCE input drain", c->self);
2082: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2083: if (buffer_len(&c->input) == 0)
2084: chan_ibuf_empty(c);
1.133 markus 2085: }
2086:
1.41 markus 2087: }
1.1 deraadt 2088:
1.249 djm 2089: /* ARGSUSED */
1.49 markus 2090: void
1.154 markus 2091: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2092: {
1.41 markus 2093: int id;
2094: Channel *c;
1.1 deraadt 2095:
1.41 markus 2096: id = packet_get_int();
1.152 markus 2097: packet_check_eom();
1.41 markus 2098: c = channel_lookup(id);
2099: if (c == NULL)
2100: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2101:
2102: /*
2103: * Send a confirmation that we have closed the channel and no more
2104: * data is coming for it.
2105: */
1.25 markus 2106: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2107: packet_put_int(c->remote_id);
1.25 markus 2108: packet_send();
2109:
1.27 markus 2110: /*
2111: * If the channel is in closed state, we have sent a close request,
2112: * and the other side will eventually respond with a confirmation.
2113: * Thus, we cannot free the channel here, because then there would be
2114: * no-one to receive the confirmation. The channel gets freed when
2115: * the confirmation arrives.
2116: */
1.41 markus 2117: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2118: /*
2119: * Not a closed channel - mark it as draining, which will
2120: * cause it to be freed later.
2121: */
1.158 markus 2122: buffer_clear(&c->input);
1.41 markus 2123: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2124: }
1.1 deraadt 2125: }
2126:
1.41 markus 2127: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2128: /* ARGSUSED */
1.49 markus 2129: void
1.154 markus 2130: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2131: {
2132: int id = packet_get_int();
2133: Channel *c = channel_lookup(id);
1.151 markus 2134:
1.152 markus 2135: packet_check_eom();
1.41 markus 2136: if (c == NULL)
2137: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2138: chan_rcvd_oclose(c);
2139: }
1.1 deraadt 2140:
1.249 djm 2141: /* ARGSUSED */
1.49 markus 2142: void
1.154 markus 2143: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2144: {
1.41 markus 2145: int id = packet_get_int();
2146: Channel *c = channel_lookup(id);
1.1 deraadt 2147:
1.152 markus 2148: packet_check_eom();
1.41 markus 2149: if (c == NULL)
2150: packet_disconnect("Received close confirmation for "
2151: "out-of-range channel %d.", id);
2152: if (c->type != SSH_CHANNEL_CLOSED)
2153: packet_disconnect("Received close confirmation for "
2154: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2155: channel_free(c);
1.1 deraadt 2156: }
2157:
1.249 djm 2158: /* ARGSUSED */
1.49 markus 2159: void
1.154 markus 2160: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2161: {
1.41 markus 2162: int id, remote_id;
2163: Channel *c;
1.1 deraadt 2164:
1.41 markus 2165: id = packet_get_int();
2166: c = channel_lookup(id);
1.25 markus 2167:
1.41 markus 2168: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2169: packet_disconnect("Received open confirmation for "
2170: "non-opening channel %d.", id);
2171: remote_id = packet_get_int();
1.27 markus 2172: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2173: c->remote_id = remote_id;
2174: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2175:
2176: if (compat20) {
2177: c->remote_window = packet_get_int();
2178: c->remote_maxpacket = packet_get_int();
1.165 markus 2179: if (c->confirm) {
1.70 markus 2180: debug2("callback start");
1.204 djm 2181: c->confirm(c->self, c->confirm_ctx);
1.70 markus 2182: debug2("callback done");
1.44 markus 2183: }
1.194 markus 2184: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2185: c->remote_window, c->remote_maxpacket);
2186: }
1.152 markus 2187: packet_check_eom();
1.1 deraadt 2188: }
2189:
1.127 itojun 2190: static char *
1.114 markus 2191: reason2txt(int reason)
2192: {
1.143 deraadt 2193: switch (reason) {
1.114 markus 2194: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2195: return "administratively prohibited";
2196: case SSH2_OPEN_CONNECT_FAILED:
2197: return "connect failed";
2198: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2199: return "unknown channel type";
2200: case SSH2_OPEN_RESOURCE_SHORTAGE:
2201: return "resource shortage";
2202: }
1.117 stevesk 2203: return "unknown reason";
1.114 markus 2204: }
2205:
1.249 djm 2206: /* ARGSUSED */
1.49 markus 2207: void
1.154 markus 2208: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2209: {
1.86 markus 2210: int id, reason;
2211: char *msg = NULL, *lang = NULL;
1.41 markus 2212: Channel *c;
2213:
2214: id = packet_get_int();
2215: c = channel_lookup(id);
1.25 markus 2216:
1.41 markus 2217: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2218: packet_disconnect("Received open failure for "
2219: "non-opening channel %d.", id);
1.44 markus 2220: if (compat20) {
1.86 markus 2221: reason = packet_get_int();
1.110 markus 2222: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2223: msg = packet_get_string(NULL);
2224: lang = packet_get_string(NULL);
2225: }
1.188 itojun 2226: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2227: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 2228: if (msg != NULL)
2229: xfree(msg);
2230: if (lang != NULL)
2231: xfree(lang);
1.44 markus 2232: }
1.152 markus 2233: packet_check_eom();
1.25 markus 2234: /* Free the channel. This will also close the socket. */
1.113 markus 2235: channel_free(c);
1.44 markus 2236: }
2237:
1.249 djm 2238: /* ARGSUSED */
1.121 markus 2239: void
1.154 markus 2240: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2241: {
2242: Channel *c;
1.178 markus 2243: int id;
2244: u_int adjust;
1.121 markus 2245:
2246: if (!compat20)
2247: return;
2248:
2249: /* Get the channel number and verify it. */
2250: id = packet_get_int();
2251: c = channel_lookup(id);
1.1 deraadt 2252:
1.229 markus 2253: if (c == NULL) {
2254: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2255: return;
2256: }
2257: adjust = packet_get_int();
1.152 markus 2258: packet_check_eom();
1.178 markus 2259: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2260: c->remote_window += adjust;
2261: }
1.1 deraadt 2262:
1.249 djm 2263: /* ARGSUSED */
1.121 markus 2264: void
1.154 markus 2265: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2266: {
1.121 markus 2267: Channel *c = NULL;
2268: u_short host_port;
2269: char *host, *originator_string;
2270: int remote_id, sock = -1;
2271:
2272: remote_id = packet_get_int();
2273: host = packet_get_string(NULL);
2274: host_port = packet_get_int();
1.25 markus 2275:
1.121 markus 2276: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2277: originator_string = packet_get_string(NULL);
2278: } else {
2279: originator_string = xstrdup("unknown (remote did not supply name)");
2280: }
1.152 markus 2281: packet_check_eom();
1.121 markus 2282: sock = channel_connect_to(host, host_port);
2283: if (sock != -1) {
2284: c = channel_new("connected socket",
2285: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2286: originator_string, 1);
1.167 markus 2287: c->remote_id = remote_id;
1.25 markus 2288: }
1.190 markus 2289: xfree(originator_string);
1.121 markus 2290: if (c == NULL) {
2291: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2292: packet_put_int(remote_id);
2293: packet_send();
2294: }
2295: xfree(host);
1.1 deraadt 2296: }
2297:
1.121 markus 2298:
2299: /* -- tcp forwarding */
1.135 markus 2300:
2301: void
2302: channel_set_af(int af)
2303: {
2304: IPv4or6 = af;
2305: }
1.121 markus 2306:
1.160 markus 2307: static int
2308: channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port,
2309: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2310: {
1.113 markus 2311: Channel *c;
1.226 djm 2312: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2313: struct addrinfo hints, *ai, *aitop;
1.212 djm 2314: const char *host, *addr;
1.35 markus 2315: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.25 markus 2316:
1.160 markus 2317: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2318: listen_addr : host_to_connect;
1.212 djm 2319: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2320:
1.160 markus 2321: if (host == NULL) {
2322: error("No forward host name.");
1.218 markus 2323: return 0;
1.73 markus 2324: }
1.113 markus 2325: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2326: error("Forward host name too long.");
1.218 markus 2327: return 0;
1.87 markus 2328: }
1.25 markus 2329:
1.28 markus 2330: /*
1.212 djm 2331: * Determine whether or not a port forward listens to loopback,
1.213 deraadt 2332: * specified address or wildcard. On the client, a specified bind
2333: * address will always override gateway_ports. On the server, a
2334: * gateway_ports of 1 (``yes'') will override the client's
2335: * specification and force a wildcard bind, whereas a value of 2
2336: * (``clientspecified'') will bind to whatever address the client
1.212 djm 2337: * asked for.
2338: *
2339: * Special-case listen_addrs are:
2340: *
2341: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2342: * "" (empty string), "*" -> wildcard v4/v6
2343: * "localhost" -> loopback v4/v6
2344: */
2345: addr = NULL;
2346: if (listen_addr == NULL) {
2347: /* No address specified: default to gateway_ports setting */
2348: if (gateway_ports)
2349: wildcard = 1;
2350: } else if (gateway_ports || is_client) {
2351: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2352: strcmp(listen_addr, "0.0.0.0") == 0) ||
2353: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2354: (!is_client && gateway_ports == 1))
2355: wildcard = 1;
2356: else if (strcmp(listen_addr, "localhost") != 0)
2357: addr = listen_addr;
2358: }
2359:
2360: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2361: type, wildcard, (addr == NULL) ? "NULL" : addr);
2362:
2363: /*
1.35 markus 2364: * getaddrinfo returns a loopback address if the hostname is
2365: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2366: */
1.35 markus 2367: memset(&hints, 0, sizeof(hints));
2368: hints.ai_family = IPv4or6;
1.212 djm 2369: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2370: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2371: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2372: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2373: if (addr == NULL) {
2374: /* This really shouldn't happen */
2375: packet_disconnect("getaddrinfo: fatal error: %s",
2376: gai_strerror(r));
2377: } else {
1.218 markus 2378: error("channel_setup_fwd_listener: "
1.212 djm 2379: "getaddrinfo(%.64s): %s", addr, gai_strerror(r));
2380: }
1.218 markus 2381: return 0;
1.212 djm 2382: }
1.35 markus 2383:
2384: for (ai = aitop; ai; ai = ai->ai_next) {
2385: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2386: continue;
2387: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2388: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2389: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2390: continue;
2391: }
2392: /* Create a port to listen for the host. */
1.189 markus 2393: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2394: if (sock < 0) {
2395: /* this is no error since kernel may not support ipv6 */
2396: verbose("socket: %.100s", strerror(errno));
2397: continue;
2398: }
1.226 djm 2399:
2400: channel_set_reuseaddr(sock);
1.182 stevesk 2401:
1.35 markus 2402: debug("Local forwarding listening on %s port %s.", ntop, strport);
2403:
2404: /* Bind the socket to the address. */
2405: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2406: /* address can be in use ipv6 address is already bound */
2407: verbose("bind: %.100s", strerror(errno));
2408: close(sock);
2409: continue;
2410: }
2411: /* Start listening for connections on the socket. */
1.199 markus 2412: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2413: error("listen: %.100s", strerror(errno));
2414: close(sock);
2415: continue;
2416: }
2417: /* Allocate a channel number for the socket. */
1.121 markus 2418: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2419: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2420: 0, "port listener", 1);
1.113 markus 2421: strlcpy(c->path, host, sizeof(c->path));
2422: c->host_port = port_to_connect;
2423: c->listening_port = listen_port;
1.35 markus 2424: success = 1;
2425: }
2426: if (success == 0)
1.160 markus 2427: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2428: listen_port);
1.35 markus 2429: freeaddrinfo(aitop);
1.87 markus 2430: return success;
1.25 markus 2431: }
1.1 deraadt 2432:
1.202 djm 2433: int
2434: channel_cancel_rport_listener(const char *host, u_short port)
2435: {
1.209 avsm 2436: u_int i;
2437: int found = 0;
1.202 djm 2438:
1.213 deraadt 2439: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2440: Channel *c = channels[i];
2441:
2442: if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
2443: strncmp(c->path, host, sizeof(c->path)) == 0 &&
1.208 deraadt 2444: c->listening_port == port) {
1.210 djm 2445: debug2("%s: close channel %d", __func__, i);
1.202 djm 2446: channel_free(c);
2447: found = 1;
2448: }
2449: }
2450:
2451: return (found);
2452: }
2453:
1.160 markus 2454: /* protocol local port fwd, used by ssh (and sshd in v1) */
2455: int
1.212 djm 2456: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2457: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2458: {
2459: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.212 djm 2460: listen_host, listen_port, host_to_connect, port_to_connect,
2461: gateway_ports);
1.160 markus 2462: }
2463:
2464: /* protocol v2 remote port fwd, used by sshd */
2465: int
2466: channel_setup_remote_fwd_listener(const char *listen_address,
2467: u_short listen_port, int gateway_ports)
2468: {
2469: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
2470: listen_address, listen_port, NULL, 0, gateway_ports);
2471: }
2472:
1.27 markus 2473: /*
2474: * Initiate forwarding of connections to port "port" on remote host through
2475: * the secure channel to host:port from local side.
2476: */
1.1 deraadt 2477:
1.253 markus 2478: int
1.212 djm 2479: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2480: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2481: {
1.153 markus 2482: int type, success = 0;
1.73 markus 2483:
1.25 markus 2484: /* Record locally that connection to this host/port is permitted. */
2485: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2486: fatal("channel_request_remote_forwarding: too many forwards");
2487:
2488: /* Send the forward request to the remote side. */
1.44 markus 2489: if (compat20) {
1.212 djm 2490: const char *address_to_bind;
2491: if (listen_host == NULL)
2492: address_to_bind = "localhost";
2493: else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0)
2494: address_to_bind = "";
2495: else
2496: address_to_bind = listen_host;
2497:
1.44 markus 2498: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2499: packet_put_cstring("tcpip-forward");
1.173 markus 2500: packet_put_char(1); /* boolean: want reply */
1.44 markus 2501: packet_put_cstring(address_to_bind);
2502: packet_put_int(listen_port);
1.73 markus 2503: packet_send();
2504: packet_write_wait();
2505: /* Assume that server accepts the request */
2506: success = 1;
1.44 markus 2507: } else {
2508: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2509: packet_put_int(listen_port);
2510: packet_put_cstring(host_to_connect);
1.44 markus 2511: packet_put_int(port_to_connect);
2512: packet_send();
2513: packet_write_wait();
1.73 markus 2514:
2515: /* Wait for response from the remote side. */
1.153 markus 2516: type = packet_read();
1.73 markus 2517: switch (type) {
2518: case SSH_SMSG_SUCCESS:
2519: success = 1;
2520: break;
2521: case SSH_SMSG_FAILURE:
2522: break;
2523: default:
2524: /* Unknown packet */
2525: packet_disconnect("Protocol error for port forward request:"
2526: "received packet type %d.", type);
2527: }
2528: }
2529: if (success) {
2530: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2531: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2532: permitted_opens[num_permitted_opens].listen_port = listen_port;
2533: num_permitted_opens++;
1.44 markus 2534: }
1.253 markus 2535: return (success ? 0 : -1);
1.1 deraadt 2536: }
2537:
1.27 markus 2538: /*
1.208 deraadt 2539: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 2540: * local side.
2541: */
2542: void
1.212 djm 2543: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 2544: {
2545: int i;
2546:
2547: if (!compat20)
2548: return;
2549:
2550: for (i = 0; i < num_permitted_opens; i++) {
1.208 deraadt 2551: if (permitted_opens[i].host_to_connect != NULL &&
1.202 djm 2552: permitted_opens[i].listen_port == port)
2553: break;
2554: }
2555: if (i >= num_permitted_opens) {
2556: debug("%s: requested forward not found", __func__);
2557: return;
2558: }
2559: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2560: packet_put_cstring("cancel-tcpip-forward");
2561: packet_put_char(0);
1.212 djm 2562: packet_put_cstring(host == NULL ? "" : host);
1.202 djm 2563: packet_put_int(port);
2564: packet_send();
2565:
2566: permitted_opens[i].listen_port = 0;
2567: permitted_opens[i].port_to_connect = 0;
1.227 stevesk 2568: xfree(permitted_opens[i].host_to_connect);
1.202 djm 2569: permitted_opens[i].host_to_connect = NULL;
2570: }
2571:
2572: /*
1.27 markus 2573: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2574: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 2575: * message if there was an error).
1.27 markus 2576: */
1.253 markus 2577: int
1.56 markus 2578: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2579: {
1.31 markus 2580: u_short port, host_port;
1.253 markus 2581: int success = 0;
1.25 markus 2582: char *hostname;
1.1 deraadt 2583:
1.25 markus 2584: /* Get arguments from the packet. */
2585: port = packet_get_int();
2586: hostname = packet_get_string(NULL);
2587: host_port = packet_get_int();
2588:
1.27 markus 2589: /*
2590: * Check that an unprivileged user is not trying to forward a
2591: * privileged port.
2592: */
1.25 markus 2593: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 2594: packet_disconnect(
2595: "Requested forwarding of port %d but user is not root.",
2596: port);
2597: if (host_port == 0)
2598: packet_disconnect("Dynamic forwarding denied.");
2599:
1.73 markus 2600: /* Initiate forwarding */
1.253 markus 2601: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 2602: host_port, gateway_ports);
1.25 markus 2603:
2604: /* Free the argument string. */
2605: xfree(hostname);
1.253 markus 2606:
2607: return (success ? 0 : -1);
1.1 deraadt 2608: }
2609:
1.99 markus 2610: /*
2611: * Permits opening to any host/port if permitted_opens[] is empty. This is
2612: * usually called by the server, because the user could connect to any port
2613: * anyway, and the server has no way to know but to trust the client anyway.
2614: */
2615: void
1.142 itojun 2616: channel_permit_all_opens(void)
1.99 markus 2617: {
2618: if (num_permitted_opens == 0)
2619: all_opens_permitted = 1;
2620: }
2621:
1.101 markus 2622: void
1.99 markus 2623: channel_add_permitted_opens(char *host, int port)
2624: {
2625: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1.253 markus 2626: fatal("channel_add_permitted_opens: too many forwards");
1.99 markus 2627: debug("allow port forwarding to host %s port %d", host, port);
2628:
2629: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2630: permitted_opens[num_permitted_opens].port_to_connect = port;
2631: num_permitted_opens++;
2632:
2633: all_opens_permitted = 0;
2634: }
2635:
1.101 markus 2636: void
1.257 ! dtucker 2637: channel_add_adm_permitted_opens(char *host, int port)
! 2638: {
! 2639: if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
! 2640: fatal("channel_add_adm_permitted_opens: too many forwards");
! 2641: debug("allow port forwarding to host %s port %d", host, port);
! 2642:
! 2643: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
! 2644: = xstrdup(host);
! 2645: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
! 2646: num_adm_permitted_opens++;
! 2647: }
! 2648:
! 2649: void
1.99 markus 2650: channel_clear_permitted_opens(void)
2651: {
2652: int i;
2653:
2654: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2655: if (permitted_opens[i].host_to_connect != NULL)
2656: xfree(permitted_opens[i].host_to_connect);
1.99 markus 2657: num_permitted_opens = 0;
1.257 ! dtucker 2658: }
! 2659:
! 2660: void
! 2661: channel_clear_adm_permitted_opens(void)
! 2662: {
! 2663: int i;
1.99 markus 2664:
1.257 ! dtucker 2665: for (i = 0; i < num_adm_permitted_opens; i++)
! 2666: if (permitted_adm_opens[i].host_to_connect != NULL)
! 2667: xfree(permitted_adm_opens[i].host_to_connect);
! 2668: num_adm_permitted_opens = 0;
1.99 markus 2669: }
2670:
2671: /* return socket to remote host, port */
1.127 itojun 2672: static int
1.99 markus 2673: connect_to(const char *host, u_short port)
1.41 markus 2674: {
2675: struct addrinfo hints, *ai, *aitop;
2676: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2677: int gaierr;
2678: int sock = -1;
2679:
2680: memset(&hints, 0, sizeof(hints));
2681: hints.ai_family = IPv4or6;
2682: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2683: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2684: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2685: error("connect_to %.100s: unknown host (%s)", host,
2686: gai_strerror(gaierr));
1.41 markus 2687: return -1;
2688: }
2689: for (ai = aitop; ai; ai = ai->ai_next) {
2690: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2691: continue;
2692: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2693: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2694: error("connect_to: getnameinfo failed");
1.41 markus 2695: continue;
2696: }
1.189 markus 2697: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.41 markus 2698: if (sock < 0) {
1.186 djm 2699: if (ai->ai_next == NULL)
2700: error("socket: %.100s", strerror(errno));
2701: else
2702: verbose("socket: %.100s", strerror(errno));
1.41 markus 2703: continue;
2704: }
1.205 djm 2705: if (set_nonblock(sock) == -1)
2706: fatal("%s: set_nonblock(%d)", __func__, sock);
1.75 markus 2707: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2708: errno != EINPROGRESS) {
1.99 markus 2709: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2710: strerror(errno));
2711: close(sock);
1.89 stevesk 2712: continue; /* fail -- try next */
1.41 markus 2713: }
2714: break; /* success */
2715:
2716: }
2717: freeaddrinfo(aitop);
2718: if (!ai) {
1.99 markus 2719: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2720: return -1;
2721: }
2722: /* success */
1.169 stevesk 2723: set_nodelay(sock);
1.41 markus 2724: return sock;
2725: }
1.99 markus 2726:
1.73 markus 2727: int
1.130 stevesk 2728: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2729: {
2730: int i;
1.99 markus 2731:
1.73 markus 2732: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2733: if (permitted_opens[i].host_to_connect != NULL &&
2734: permitted_opens[i].listen_port == listen_port)
1.99 markus 2735: return connect_to(
1.73 markus 2736: permitted_opens[i].host_to_connect,
2737: permitted_opens[i].port_to_connect);
1.74 markus 2738: error("WARNING: Server requests forwarding for unknown listen_port %d",
2739: listen_port);
1.73 markus 2740: return -1;
2741: }
2742:
1.99 markus 2743: /* Check if connecting to that port is permitted and connect. */
2744: int
2745: channel_connect_to(const char *host, u_short port)
2746: {
1.257 ! dtucker 2747: int i, permit, permit_adm = 1;
1.99 markus 2748:
2749: permit = all_opens_permitted;
2750: if (!permit) {
2751: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2752: if (permitted_opens[i].host_to_connect != NULL &&
2753: permitted_opens[i].port_to_connect == port &&
1.99 markus 2754: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2755: permit = 1;
1.257 ! dtucker 2756: }
1.99 markus 2757:
1.257 ! dtucker 2758: if (num_adm_permitted_opens > 0) {
! 2759: permit_adm = 0;
! 2760: for (i = 0; i < num_adm_permitted_opens; i++)
! 2761: if (permitted_adm_opens[i].host_to_connect != NULL &&
! 2762: permitted_adm_opens[i].port_to_connect == port &&
! 2763: strcmp(permitted_adm_opens[i].host_to_connect, host)
! 2764: == 0)
! 2765: permit_adm = 1;
1.99 markus 2766: }
1.257 ! dtucker 2767:
! 2768: if (!permit || !permit_adm) {
1.188 itojun 2769: logit("Received request to connect to host %.100s port %d, "
1.99 markus 2770: "but the request was denied.", host, port);
2771: return -1;
2772: }
2773: return connect_to(host, port);
1.204 djm 2774: }
2775:
2776: void
2777: channel_send_window_changes(void)
2778: {
1.209 avsm 2779: u_int i;
1.204 djm 2780: struct winsize ws;
2781:
2782: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 2783: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 2784: channels[i]->type != SSH_CHANNEL_OPEN)
2785: continue;
2786: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
2787: continue;
2788: channel_request_start(i, "window-change", 0);
1.238 deraadt 2789: packet_put_int((u_int)ws.ws_col);
2790: packet_put_int((u_int)ws.ws_row);
2791: packet_put_int((u_int)ws.ws_xpixel);
2792: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 2793: packet_send();
2794: }
1.99 markus 2795: }
2796:
1.121 markus 2797: /* -- X11 forwarding */
1.1 deraadt 2798:
1.27 markus 2799: /*
2800: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 2801: * Returns 0 and a suitable display number for the DISPLAY variable
2802: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 2803: */
1.141 stevesk 2804: int
1.163 stevesk 2805: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 2806: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 2807: {
1.149 markus 2808: Channel *nc = NULL;
1.31 markus 2809: int display_number, sock;
2810: u_short port;
1.35 markus 2811: struct addrinfo hints, *ai, *aitop;
2812: char strport[NI_MAXSERV];
2813: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 2814:
1.224 markus 2815: if (chanids == NULL)
2816: return -1;
2817:
1.33 markus 2818: for (display_number = x11_display_offset;
1.148 deraadt 2819: display_number < MAX_DISPLAYS;
2820: display_number++) {
1.25 markus 2821: port = 6000 + display_number;
1.35 markus 2822: memset(&hints, 0, sizeof(hints));
2823: hints.ai_family = IPv4or6;
1.163 stevesk 2824: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 2825: hints.ai_socktype = SOCK_STREAM;
2826: snprintf(strport, sizeof strport, "%d", port);
2827: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2828: error("getaddrinfo: %.100s", gai_strerror(gaierr));
1.141 stevesk 2829: return -1;
1.25 markus 2830: }
1.35 markus 2831: for (ai = aitop; ai; ai = ai->ai_next) {
2832: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2833: continue;
1.189 markus 2834: sock = socket(ai->ai_family, ai->ai_socktype,
2835: ai->ai_protocol);
1.35 markus 2836: if (sock < 0) {
2837: error("socket: %.100s", strerror(errno));
1.203 markus 2838: freeaddrinfo(aitop);
1.141 stevesk 2839: return -1;
1.35 markus 2840: }
1.226 djm 2841: channel_set_reuseaddr(sock);
1.35 markus 2842: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 2843: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 2844: close(sock);
1.183 itojun 2845:
2846: if (ai->ai_next)
2847: continue;
2848:
1.35 markus 2849: for (n = 0; n < num_socks; n++) {
2850: close(socks[n]);
2851: }
2852: num_socks = 0;
2853: break;
2854: }
2855: socks[num_socks++] = sock;
2856: if (num_socks == NUM_SOCKS)
2857: break;
1.25 markus 2858: }
1.83 stevesk 2859: freeaddrinfo(aitop);
1.35 markus 2860: if (num_socks > 0)
2861: break;
1.25 markus 2862: }
2863: if (display_number >= MAX_DISPLAYS) {
2864: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 2865: return -1;
1.25 markus 2866: }
2867: /* Start listening for connections on the socket. */
1.35 markus 2868: for (n = 0; n < num_socks; n++) {
2869: sock = socks[n];
1.199 markus 2870: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2871: error("listen: %.100s", strerror(errno));
2872: close(sock);
1.141 stevesk 2873: return -1;
1.35 markus 2874: }
1.25 markus 2875: }
1.35 markus 2876:
2877: /* Allocate a channel for each socket. */
1.242 djm 2878: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 2879: for (n = 0; n < num_socks; n++) {
2880: sock = socks[n];
1.149 markus 2881: nc = channel_new("x11 listener",
1.51 markus 2882: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2883: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 2884: 0, "X11 inet listener", 1);
1.167 markus 2885: nc->single_connection = single_connection;
1.224 markus 2886: (*chanids)[n] = nc->self;
1.35 markus 2887: }
1.224 markus 2888: (*chanids)[n] = -1;
1.1 deraadt 2889:
1.141 stevesk 2890: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 2891: *display_numberp = display_number;
2892: return (0);
1.1 deraadt 2893: }
2894:
1.127 itojun 2895: static int
1.77 markus 2896: connect_local_xsocket(u_int dnr)
1.1 deraadt 2897: {
1.25 markus 2898: int sock;
2899: struct sockaddr_un addr;
2900:
1.147 stevesk 2901: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2902: if (sock < 0)
2903: error("socket: %.100s", strerror(errno));
2904: memset(&addr, 0, sizeof(addr));
2905: addr.sun_family = AF_UNIX;
2906: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 2907: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 2908: return sock;
2909: close(sock);
1.25 markus 2910: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2911: return -1;
1.1 deraadt 2912: }
2913:
1.51 markus 2914: int
2915: x11_connect_display(void)
1.1 deraadt 2916: {
1.248 deraadt 2917: u_int display_number;
1.25 markus 2918: const char *display;
1.51 markus 2919: char buf[1024], *cp;
1.35 markus 2920: struct addrinfo hints, *ai, *aitop;
2921: char strport[NI_MAXSERV];
1.248 deraadt 2922: int gaierr, sock = 0;
1.25 markus 2923:
2924: /* Try to open a socket for the local X server. */
2925: display = getenv("DISPLAY");
2926: if (!display) {
2927: error("DISPLAY not set.");
1.51 markus 2928: return -1;
1.25 markus 2929: }
1.27 markus 2930: /*
2931: * Now we decode the value of the DISPLAY variable and make a
2932: * connection to the real X server.
2933: */
2934:
2935: /*
2936: * Check if it is a unix domain socket. Unix domain displays are in
2937: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2938: */
1.25 markus 2939: if (strncmp(display, "unix:", 5) == 0 ||
2940: display[0] == ':') {
2941: /* Connect to the unix domain socket. */
1.248 deraadt 2942: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 2943: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2944: display);
1.51 markus 2945: return -1;
1.25 markus 2946: }
2947: /* Create a socket. */
2948: sock = connect_local_xsocket(display_number);
2949: if (sock < 0)
1.51 markus 2950: return -1;
1.25 markus 2951:
2952: /* OK, we now have a connection to the display. */
1.51 markus 2953: return sock;
1.25 markus 2954: }
1.27 markus 2955: /*
2956: * Connect to an inet socket. The DISPLAY value is supposedly
2957: * hostname:d[.s], where hostname may also be numeric IP address.
2958: */
1.145 stevesk 2959: strlcpy(buf, display, sizeof(buf));
1.25 markus 2960: cp = strchr(buf, ':');
2961: if (!cp) {
2962: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 2963: return -1;
1.25 markus 2964: }
2965: *cp = 0;
1.27 markus 2966: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 2967: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 2968: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2969: display);
1.51 markus 2970: return -1;
1.25 markus 2971: }
1.35 markus 2972:
2973: /* Look up the host address */
2974: memset(&hints, 0, sizeof(hints));
2975: hints.ai_family = IPv4or6;
2976: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 2977: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 2978: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2979: error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
1.51 markus 2980: return -1;
1.25 markus 2981: }
1.35 markus 2982: for (ai = aitop; ai; ai = ai->ai_next) {
2983: /* Create a socket. */
1.189 markus 2984: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2985: if (sock < 0) {
1.194 markus 2986: debug2("socket: %.100s", strerror(errno));
1.41 markus 2987: continue;
2988: }
2989: /* Connect it to the display. */
2990: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 2991: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 2992: 6000 + display_number, strerror(errno));
2993: close(sock);
2994: continue;
2995: }
2996: /* Success */
2997: break;
1.35 markus 2998: }
2999: freeaddrinfo(aitop);
3000: if (!ai) {
1.248 deraadt 3001: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3002: strerror(errno));
1.51 markus 3003: return -1;
1.25 markus 3004: }
1.162 stevesk 3005: set_nodelay(sock);
1.51 markus 3006: return sock;
3007: }
3008:
3009: /*
3010: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3011: * the remote channel number. We should do whatever we want, and respond
3012: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3013: */
3014:
3015: void
1.154 markus 3016: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3017: {
1.113 markus 3018: Channel *c = NULL;
3019: int remote_id, sock = 0;
1.51 markus 3020: char *remote_host;
1.25 markus 3021:
1.113 markus 3022: debug("Received X11 open request.");
1.51 markus 3023:
1.113 markus 3024: remote_id = packet_get_int();
1.121 markus 3025:
3026: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3027: remote_host = packet_get_string(NULL);
1.51 markus 3028: } else {
3029: remote_host = xstrdup("unknown (remote did not supply name)");
3030: }
1.152 markus 3031: packet_check_eom();
1.25 markus 3032:
1.51 markus 3033: /* Obtain a connection to the real X display. */
3034: sock = x11_connect_display();
1.113 markus 3035: if (sock != -1) {
3036: /* Allocate a channel for this connection. */
3037: c = channel_new("connected x11 socket",
3038: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3039: remote_host, 1);
1.167 markus 3040: c->remote_id = remote_id;
3041: c->force_drain = 1;
1.113 markus 3042: }
1.190 markus 3043: xfree(remote_host);
1.113 markus 3044: if (c == NULL) {
1.51 markus 3045: /* Send refusal to the remote host. */
3046: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3047: packet_put_int(remote_id);
1.51 markus 3048: } else {
3049: /* Send a confirmation to the remote host. */
3050: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3051: packet_put_int(remote_id);
3052: packet_put_int(c->self);
1.51 markus 3053: }
1.113 markus 3054: packet_send();
1.72 markus 3055: }
3056:
3057: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
3058: void
1.154 markus 3059: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3060: {
3061: int rchan = packet_get_int();
1.180 deraadt 3062:
1.143 deraadt 3063: switch (type) {
1.72 markus 3064: case SSH_SMSG_AGENT_OPEN:
3065: error("Warning: ssh server tried agent forwarding.");
3066: break;
3067: case SSH_SMSG_X11_OPEN:
3068: error("Warning: ssh server tried X11 forwarding.");
3069: break;
3070: default:
1.154 markus 3071: error("deny_input_open: type %d", type);
1.72 markus 3072: break;
3073: }
1.230 stevesk 3074: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3075: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3076: packet_put_int(rchan);
3077: packet_send();
1.1 deraadt 3078: }
3079:
1.27 markus 3080: /*
3081: * Requests forwarding of X11 connections, generates fake authentication
3082: * data, and enables authentication spoofing.
1.121 markus 3083: * This should be called in the client only.
1.27 markus 3084: */
1.49 markus 3085: void
1.215 djm 3086: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.51 markus 3087: const char *proto, const char *data)
1.1 deraadt 3088: {
1.77 markus 3089: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3090: u_int i, value;
1.25 markus 3091: char *new_data;
3092: int screen_number;
3093: const char *cp;
1.207 avsm 3094: u_int32_t rnd = 0;
1.25 markus 3095:
1.220 markus 3096: if (x11_saved_display == NULL)
3097: x11_saved_display = xstrdup(disp);
3098: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3099: error("x11_request_forwarding_with_spoofing: different "
3100: "$DISPLAY already forwarded");
3101: return;
3102: }
3103:
1.215 djm 3104: cp = disp;
3105: if (disp)
3106: cp = strchr(disp, ':');
1.25 markus 3107: if (cp)
3108: cp = strchr(cp, '.');
3109: if (cp)
1.245 deraadt 3110: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3111: else
3112: screen_number = 0;
3113:
1.219 djm 3114: if (x11_saved_proto == NULL) {
3115: /* Save protocol name. */
3116: x11_saved_proto = xstrdup(proto);
3117: /*
1.221 djm 3118: * Extract real authentication data and generate fake data
1.219 djm 3119: * of the same length.
3120: */
3121: x11_saved_data = xmalloc(data_len);
3122: x11_fake_data = xmalloc(data_len);
3123: for (i = 0; i < data_len; i++) {
3124: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3125: fatal("x11_request_forwarding: bad "
3126: "authentication data: %.100s", data);
3127: if (i % 4 == 0)
3128: rnd = arc4random();
3129: x11_saved_data[i] = value;
3130: x11_fake_data[i] = rnd & 0xff;
3131: rnd >>= 8;
3132: }
3133: x11_saved_data_len = data_len;
3134: x11_fake_data_len = data_len;
1.25 markus 3135: }
3136:
3137: /* Convert the fake data into hex. */
1.219 djm 3138: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3139:
3140: /* Send the request packet. */
1.51 markus 3141: if (compat20) {
3142: channel_request_start(client_session_id, "x11-req", 0);
3143: packet_put_char(0); /* XXX bool single connection */
3144: } else {
3145: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3146: }
3147: packet_put_cstring(proto);
3148: packet_put_cstring(new_data);
1.25 markus 3149: packet_put_int(screen_number);
3150: packet_send();
3151: packet_write_wait();
3152: xfree(new_data);
1.1 deraadt 3153: }
3154:
1.121 markus 3155:
3156: /* -- agent forwarding */
3157:
1.1 deraadt 3158: /* Sends a message to the server to request authentication fd forwarding. */
3159:
1.49 markus 3160: void
1.142 itojun 3161: auth_request_forwarding(void)
1.1 deraadt 3162: {
1.25 markus 3163: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3164: packet_send();
3165: packet_write_wait();
1.1 deraadt 3166: }
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