Annotation of src/usr.bin/ssh/channels.c, Revision 1.263
1.263 ! stevesk 1: /* $OpenBSD: channels.c,v 1.262 2006/07/26 13:57:17 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>
1.261 stevesk 48: #include <sys/time.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.255 stevesk 54: #include <netdb.h>
1.263 ! stevesk 55: #include <stdio.h>
1.262 stevesk 56: #include <stdlib.h>
1.260 stevesk 57: #include <string.h>
1.233 stevesk 58: #include <termios.h>
1.256 stevesk 59: #include <unistd.h>
1.1 deraadt 60:
61: #include "ssh.h"
1.82 markus 62: #include "ssh1.h"
63: #include "ssh2.h"
1.1 deraadt 64: #include "packet.h"
65: #include "xmalloc.h"
1.82 markus 66: #include "log.h"
67: #include "misc.h"
1.14 markus 68: #include "channels.h"
69: #include "compat.h"
1.82 markus 70: #include "canohost.h"
1.64 markus 71: #include "key.h"
72: #include "authfd.h"
1.147 stevesk 73: #include "pathnames.h"
1.193 markus 74: #include "bufaux.h"
1.1 deraadt 75:
1.121 markus 76: /* -- channel core */
1.12 markus 77:
1.27 markus 78: /*
79: * Pointer to an array containing all allocated channels. The array is
80: * dynamically extended as needed.
81: */
1.113 markus 82: static Channel **channels = NULL;
1.1 deraadt 83:
1.27 markus 84: /*
85: * Size of the channel array. All slots of the array must always be
1.113 markus 86: * initialized (at least the type field); unused slots set to NULL
1.27 markus 87: */
1.209 avsm 88: static u_int channels_alloc = 0;
1.1 deraadt 89:
1.27 markus 90: /*
91: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 92: * updated in channel_new.
1.27 markus 93: */
1.84 markus 94: static int channel_max_fd = 0;
1.1 deraadt 95:
96:
1.121 markus 97: /* -- tcp forwarding */
1.1 deraadt 98:
1.27 markus 99: /*
100: * Data structure for storing which hosts are permitted for forward requests.
101: * The local sides of any remote forwards are stored in this array to prevent
102: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
103: * network (which might be behind a firewall).
104: */
1.25 markus 105: typedef struct {
1.41 markus 106: char *host_to_connect; /* Connect to 'host'. */
107: u_short port_to_connect; /* Connect to 'port'. */
108: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 109: } ForwardPermission;
110:
1.257 dtucker 111: /* List of all permitted host/port pairs to connect by the user. */
1.1 deraadt 112: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 113:
1.257 dtucker 114: /* List of all permitted host/port pairs to connect by the admin. */
115: static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
116:
117: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 118: static int num_permitted_opens = 0;
1.257 dtucker 119:
120: /* Number of permitted host/port pair in the array permitted by the admin. */
121: static int num_adm_permitted_opens = 0;
122:
1.27 markus 123: /*
124: * If this is true, all opens are permitted. This is the case on the server
125: * on which we have to trust the client anyway, and the user could do
126: * anything after logging in anyway.
127: */
1.1 deraadt 128: static int all_opens_permitted = 0;
129:
1.121 markus 130:
131: /* -- X11 forwarding */
132:
133: /* Maximum number of fake X11 displays to try. */
134: #define MAX_DISPLAYS 1000
135:
1.219 djm 136: /* Saved X11 local (client) display. */
137: static char *x11_saved_display = NULL;
138:
1.121 markus 139: /* Saved X11 authentication protocol name. */
140: static char *x11_saved_proto = NULL;
141:
142: /* Saved X11 authentication data. This is the real data. */
143: static char *x11_saved_data = NULL;
144: static u_int x11_saved_data_len = 0;
145:
146: /*
147: * Fake X11 authentication data. This is what the server will be sending us;
148: * we should replace any occurrences of this by the real data.
149: */
1.240 deraadt 150: static u_char *x11_fake_data = NULL;
1.121 markus 151: static u_int x11_fake_data_len;
152:
153:
154: /* -- agent forwarding */
155:
156: #define NUM_SOCKS 10
157:
1.82 markus 158: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 159: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 160:
1.121 markus 161: /* helper */
1.127 itojun 162: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 163:
1.121 markus 164: /* -- channel core */
1.41 markus 165:
166: Channel *
1.229 markus 167: channel_by_id(int id)
1.41 markus 168: {
169: Channel *c;
1.113 markus 170:
1.209 avsm 171: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 172: logit("channel_by_id: %d: bad id", id);
1.41 markus 173: return NULL;
174: }
1.113 markus 175: c = channels[id];
176: if (c == NULL) {
1.229 markus 177: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 178: return NULL;
179: }
180: return c;
1.55 markus 181: }
182:
1.27 markus 183: /*
1.229 markus 184: * Returns the channel if it is allowed to receive protocol messages.
185: * Private channels, like listening sockets, may not receive messages.
186: */
187: Channel *
188: channel_lookup(int id)
189: {
190: Channel *c;
191:
192: if ((c = channel_by_id(id)) == NULL)
193: return (NULL);
194:
1.237 deraadt 195: switch (c->type) {
1.229 markus 196: case SSH_CHANNEL_X11_OPEN:
197: case SSH_CHANNEL_LARVAL:
198: case SSH_CHANNEL_CONNECTING:
199: case SSH_CHANNEL_DYNAMIC:
200: case SSH_CHANNEL_OPENING:
201: case SSH_CHANNEL_OPEN:
202: case SSH_CHANNEL_INPUT_DRAINING:
203: case SSH_CHANNEL_OUTPUT_DRAINING:
204: return (c);
205: }
206: logit("Non-public channel %d, type %d.", id, c->type);
207: return (NULL);
208: }
209:
210: /*
1.55 markus 211: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 212: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 213: */
1.127 itojun 214: static void
1.71 markus 215: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
216: int extusage, int nonblock)
1.1 deraadt 217: {
1.25 markus 218: /* Update the maximum file descriptor value. */
1.84 markus 219: channel_max_fd = MAX(channel_max_fd, rfd);
220: channel_max_fd = MAX(channel_max_fd, wfd);
221: channel_max_fd = MAX(channel_max_fd, efd);
222:
1.27 markus 223: /* XXX set close-on-exec -markus */
1.55 markus 224:
1.52 markus 225: c->rfd = rfd;
226: c->wfd = wfd;
227: c->sock = (rfd == wfd) ? rfd : -1;
1.204 djm 228: c->ctl_fd = -1; /* XXX: set elsewhere */
1.52 markus 229: c->efd = efd;
230: c->extended_usage = extusage;
1.71 markus 231:
1.91 markus 232: /* XXX ugly hack: nonblock is only set by the server */
233: if (nonblock && isatty(c->rfd)) {
1.194 markus 234: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 235: c->isatty = 1;
236: if (!isatty(c->wfd)) {
1.94 markus 237: error("channel %d: wfd %d is not a tty?",
1.91 markus 238: c->self, c->wfd);
239: }
240: } else {
241: c->isatty = 0;
242: }
243:
1.71 markus 244: /* enable nonblocking mode */
245: if (nonblock) {
246: if (rfd != -1)
247: set_nonblock(rfd);
248: if (wfd != -1)
249: set_nonblock(wfd);
250: if (efd != -1)
251: set_nonblock(efd);
252: }
1.52 markus 253: }
254:
255: /*
256: * Allocate a new channel object and set its type and socket. This will cause
257: * remote_name to be freed.
258: */
1.113 markus 259: Channel *
1.52 markus 260: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 261: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 262: {
1.209 avsm 263: int found;
264: u_int i;
1.52 markus 265: Channel *c;
1.25 markus 266:
267: /* Do initial allocation if this is the first call. */
268: if (channels_alloc == 0) {
269: channels_alloc = 10;
1.242 djm 270: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 271: for (i = 0; i < channels_alloc; i++)
1.113 markus 272: channels[i] = NULL;
1.25 markus 273: }
274: /* Try to find a free slot where to put the new channel. */
275: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 276: if (channels[i] == NULL) {
1.25 markus 277: /* Found a free slot. */
1.209 avsm 278: found = (int)i;
1.25 markus 279: break;
280: }
1.209 avsm 281: if (found < 0) {
1.27 markus 282: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 283: found = channels_alloc;
1.179 markus 284: if (channels_alloc > 10000)
285: fatal("channel_new: internal error: channels_alloc %d "
286: "too big.", channels_alloc);
1.243 djm 287: channels = xrealloc(channels, channels_alloc + 10,
288: sizeof(Channel *));
1.195 markus 289: channels_alloc += 10;
1.70 markus 290: debug2("channel: expanding %d", channels_alloc);
1.25 markus 291: for (i = found; i < channels_alloc; i++)
1.113 markus 292: channels[i] = NULL;
1.25 markus 293: }
1.113 markus 294: /* Initialize and return new channel. */
1.242 djm 295: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 296: buffer_init(&c->input);
297: buffer_init(&c->output);
1.41 markus 298: buffer_init(&c->extended);
1.159 markus 299: c->ostate = CHAN_OUTPUT_OPEN;
300: c->istate = CHAN_INPUT_OPEN;
301: c->flags = 0;
1.71 markus 302: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
1.25 markus 303: c->self = found;
304: c->type = type;
1.41 markus 305: c->ctype = ctype;
1.51 markus 306: c->local_window = window;
307: c->local_window_max = window;
308: c->local_consumed = 0;
309: c->local_maxpacket = maxpack;
1.25 markus 310: c->remote_id = -1;
1.190 markus 311: c->remote_name = xstrdup(remote_name);
1.41 markus 312: c->remote_window = 0;
313: c->remote_maxpacket = 0;
1.133 markus 314: c->force_drain = 0;
1.149 markus 315: c->single_connection = 0;
1.131 markus 316: c->detach_user = NULL;
1.225 djm 317: c->detach_close = 0;
1.165 markus 318: c->confirm = NULL;
1.204 djm 319: c->confirm_ctx = NULL;
1.65 markus 320: c->input_filter = NULL;
1.231 reyk 321: c->output_filter = NULL;
1.25 markus 322: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 323: return c;
1.1 deraadt 324: }
1.52 markus 325:
1.132 markus 326: static int
327: channel_find_maxfd(void)
328: {
1.209 avsm 329: u_int i;
330: int max = 0;
1.132 markus 331: Channel *c;
332:
333: for (i = 0; i < channels_alloc; i++) {
334: c = channels[i];
335: if (c != NULL) {
336: max = MAX(max, c->rfd);
337: max = MAX(max, c->wfd);
338: max = MAX(max, c->efd);
339: }
340: }
341: return max;
342: }
343:
344: int
345: channel_close_fd(int *fdp)
346: {
347: int ret = 0, fd = *fdp;
348:
349: if (fd != -1) {
350: ret = close(fd);
351: *fdp = -1;
352: if (fd == channel_max_fd)
353: channel_max_fd = channel_find_maxfd();
354: }
355: return ret;
356: }
357:
1.52 markus 358: /* Close all channel fd/socket. */
1.127 itojun 359: static void
1.52 markus 360: channel_close_fds(Channel *c)
361: {
1.204 djm 362: debug3("channel %d: close_fds r %d w %d e %d c %d",
363: c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
1.118 markus 364:
1.132 markus 365: channel_close_fd(&c->sock);
1.204 djm 366: channel_close_fd(&c->ctl_fd);
1.132 markus 367: channel_close_fd(&c->rfd);
368: channel_close_fd(&c->wfd);
369: channel_close_fd(&c->efd);
1.121 markus 370: }
371:
372: /* Free the channel and close its fd/socket. */
373: void
374: channel_free(Channel *c)
375: {
376: char *s;
1.209 avsm 377: u_int i, n;
1.121 markus 378:
379: for (n = 0, i = 0; i < channels_alloc; i++)
380: if (channels[i])
381: n++;
1.209 avsm 382: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 383: c->remote_name ? c->remote_name : "???", n);
384:
385: s = channel_open_message();
1.194 markus 386: debug3("channel %d: status: %s", c->self, s);
1.121 markus 387: xfree(s);
388:
389: if (c->sock != -1)
390: shutdown(c->sock, SHUT_RDWR);
1.204 djm 391: if (c->ctl_fd != -1)
392: shutdown(c->ctl_fd, SHUT_RDWR);
1.121 markus 393: channel_close_fds(c);
394: buffer_free(&c->input);
395: buffer_free(&c->output);
396: buffer_free(&c->extended);
397: if (c->remote_name) {
398: xfree(c->remote_name);
399: c->remote_name = NULL;
400: }
401: channels[c->self] = NULL;
402: xfree(c);
403: }
404:
405: void
1.126 markus 406: channel_free_all(void)
1.121 markus 407: {
1.209 avsm 408: u_int i;
1.121 markus 409:
1.126 markus 410: for (i = 0; i < channels_alloc; i++)
411: if (channels[i] != NULL)
412: channel_free(channels[i]);
1.131 markus 413: }
414:
1.121 markus 415: /*
416: * Closes the sockets/fds of all channels. This is used to close extra file
417: * descriptors after a fork.
418: */
419: void
1.142 itojun 420: channel_close_all(void)
1.121 markus 421: {
1.209 avsm 422: u_int i;
1.121 markus 423:
424: for (i = 0; i < channels_alloc; i++)
425: if (channels[i] != NULL)
426: channel_close_fds(channels[i]);
427: }
428:
429: /*
1.131 markus 430: * Stop listening to channels.
431: */
432: void
433: channel_stop_listening(void)
434: {
1.209 avsm 435: u_int i;
1.131 markus 436: Channel *c;
437:
438: for (i = 0; i < channels_alloc; i++) {
439: c = channels[i];
440: if (c != NULL) {
441: switch (c->type) {
442: case SSH_CHANNEL_AUTH_SOCKET:
443: case SSH_CHANNEL_PORT_LISTENER:
444: case SSH_CHANNEL_RPORT_LISTENER:
445: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 446: channel_close_fd(&c->sock);
1.131 markus 447: channel_free(c);
448: break;
449: }
450: }
451: }
452: }
453:
454: /*
1.121 markus 455: * Returns true if no channel has too much buffered data, and false if one or
456: * more channel is overfull.
457: */
458: int
1.142 itojun 459: channel_not_very_much_buffered_data(void)
1.121 markus 460: {
461: u_int i;
462: Channel *c;
463:
464: for (i = 0; i < channels_alloc; i++) {
465: c = channels[i];
466: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 467: #if 0
468: if (!compat20 &&
469: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 470: debug2("channel %d: big input buffer %d",
1.121 markus 471: c->self, buffer_len(&c->input));
472: return 0;
473: }
1.136 markus 474: #endif
1.121 markus 475: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 476: debug2("channel %d: big output buffer %u > %u",
1.136 markus 477: c->self, buffer_len(&c->output),
478: packet_get_maxsize());
1.121 markus 479: return 0;
480: }
481: }
482: }
483: return 1;
484: }
485:
486: /* Returns true if any channel is still open. */
487: int
1.142 itojun 488: channel_still_open(void)
1.121 markus 489: {
1.209 avsm 490: u_int i;
1.121 markus 491: Channel *c;
492:
493: for (i = 0; i < channels_alloc; i++) {
494: c = channels[i];
495: if (c == NULL)
496: continue;
497: switch (c->type) {
498: case SSH_CHANNEL_X11_LISTENER:
499: case SSH_CHANNEL_PORT_LISTENER:
500: case SSH_CHANNEL_RPORT_LISTENER:
501: case SSH_CHANNEL_CLOSED:
502: case SSH_CHANNEL_AUTH_SOCKET:
503: case SSH_CHANNEL_DYNAMIC:
504: case SSH_CHANNEL_CONNECTING:
505: case SSH_CHANNEL_ZOMBIE:
506: continue;
507: case SSH_CHANNEL_LARVAL:
508: if (!compat20)
509: fatal("cannot happen: SSH_CHANNEL_LARVAL");
510: continue;
511: case SSH_CHANNEL_OPENING:
512: case SSH_CHANNEL_OPEN:
513: case SSH_CHANNEL_X11_OPEN:
514: return 1;
515: case SSH_CHANNEL_INPUT_DRAINING:
516: case SSH_CHANNEL_OUTPUT_DRAINING:
517: if (!compat13)
518: fatal("cannot happen: OUT_DRAIN");
519: return 1;
520: default:
521: fatal("channel_still_open: bad channel type %d", c->type);
522: /* NOTREACHED */
523: }
524: }
525: return 0;
526: }
527:
528: /* Returns the id of an open channel suitable for keepaliving */
529: int
1.142 itojun 530: channel_find_open(void)
1.121 markus 531: {
1.209 avsm 532: u_int i;
1.121 markus 533: Channel *c;
534:
535: for (i = 0; i < channels_alloc; i++) {
536: c = channels[i];
1.206 djm 537: if (c == NULL || c->remote_id < 0)
1.121 markus 538: continue;
539: switch (c->type) {
540: case SSH_CHANNEL_CLOSED:
541: case SSH_CHANNEL_DYNAMIC:
542: case SSH_CHANNEL_X11_LISTENER:
543: case SSH_CHANNEL_PORT_LISTENER:
544: case SSH_CHANNEL_RPORT_LISTENER:
545: case SSH_CHANNEL_OPENING:
546: case SSH_CHANNEL_CONNECTING:
547: case SSH_CHANNEL_ZOMBIE:
548: continue;
549: case SSH_CHANNEL_LARVAL:
550: case SSH_CHANNEL_AUTH_SOCKET:
551: case SSH_CHANNEL_OPEN:
552: case SSH_CHANNEL_X11_OPEN:
553: return i;
554: case SSH_CHANNEL_INPUT_DRAINING:
555: case SSH_CHANNEL_OUTPUT_DRAINING:
556: if (!compat13)
557: fatal("cannot happen: OUT_DRAIN");
558: return i;
559: default:
560: fatal("channel_find_open: bad channel type %d", c->type);
561: /* NOTREACHED */
562: }
563: }
564: return -1;
565: }
566:
567:
568: /*
569: * Returns a message describing the currently open forwarded connections,
570: * suitable for sending to the client. The message contains crlf pairs for
571: * newlines.
572: */
573: char *
1.142 itojun 574: channel_open_message(void)
1.121 markus 575: {
576: Buffer buffer;
577: Channel *c;
578: char buf[1024], *cp;
1.209 avsm 579: u_int i;
1.121 markus 580:
581: buffer_init(&buffer);
582: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
583: buffer_append(&buffer, buf, strlen(buf));
584: for (i = 0; i < channels_alloc; i++) {
585: c = channels[i];
586: if (c == NULL)
587: continue;
588: switch (c->type) {
589: case SSH_CHANNEL_X11_LISTENER:
590: case SSH_CHANNEL_PORT_LISTENER:
591: case SSH_CHANNEL_RPORT_LISTENER:
592: case SSH_CHANNEL_CLOSED:
593: case SSH_CHANNEL_AUTH_SOCKET:
594: case SSH_CHANNEL_ZOMBIE:
595: continue;
596: case SSH_CHANNEL_LARVAL:
597: case SSH_CHANNEL_OPENING:
598: case SSH_CHANNEL_CONNECTING:
599: case SSH_CHANNEL_DYNAMIC:
600: case SSH_CHANNEL_OPEN:
601: case SSH_CHANNEL_X11_OPEN:
602: case SSH_CHANNEL_INPUT_DRAINING:
603: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 604: snprintf(buf, sizeof buf,
605: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
1.121 markus 606: c->self, c->remote_name,
607: c->type, c->remote_id,
608: c->istate, buffer_len(&c->input),
609: c->ostate, buffer_len(&c->output),
1.204 djm 610: c->rfd, c->wfd, c->ctl_fd);
1.121 markus 611: buffer_append(&buffer, buf, strlen(buf));
612: continue;
613: default:
614: fatal("channel_open_message: bad channel type %d", c->type);
615: /* NOTREACHED */
616: }
617: }
618: buffer_append(&buffer, "\0", 1);
619: cp = xstrdup(buffer_ptr(&buffer));
620: buffer_free(&buffer);
621: return cp;
622: }
623:
624: void
625: channel_send_open(int id)
626: {
627: Channel *c = channel_lookup(id);
1.180 deraadt 628:
1.121 markus 629: if (c == NULL) {
1.188 itojun 630: logit("channel_send_open: %d: bad id", id);
1.121 markus 631: return;
632: }
1.184 markus 633: debug2("channel %d: send open", id);
1.121 markus 634: packet_start(SSH2_MSG_CHANNEL_OPEN);
635: packet_put_cstring(c->ctype);
636: packet_put_int(c->self);
637: packet_put_int(c->local_window);
638: packet_put_int(c->local_maxpacket);
639: packet_send();
640: }
641:
642: void
1.184 markus 643: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 644: {
1.184 markus 645: Channel *c = channel_lookup(id);
1.180 deraadt 646:
1.121 markus 647: if (c == NULL) {
1.188 itojun 648: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 649: return;
650: }
1.204 djm 651: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 652: packet_start(SSH2_MSG_CHANNEL_REQUEST);
653: packet_put_int(c->remote_id);
654: packet_put_cstring(service);
655: packet_put_char(wantconfirm);
656: }
1.241 deraadt 657:
1.121 markus 658: void
1.204 djm 659: channel_register_confirm(int id, channel_callback_fn *fn, void *ctx)
1.121 markus 660: {
661: Channel *c = channel_lookup(id);
1.180 deraadt 662:
1.121 markus 663: if (c == NULL) {
1.188 itojun 664: logit("channel_register_comfirm: %d: bad id", id);
1.121 markus 665: return;
666: }
1.165 markus 667: c->confirm = fn;
1.204 djm 668: c->confirm_ctx = ctx;
1.121 markus 669: }
1.241 deraadt 670:
1.121 markus 671: void
1.225 djm 672: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 673: {
1.229 markus 674: Channel *c = channel_by_id(id);
1.180 deraadt 675:
1.121 markus 676: if (c == NULL) {
1.188 itojun 677: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 678: return;
679: }
1.131 markus 680: c->detach_user = fn;
1.225 djm 681: c->detach_close = do_close;
1.121 markus 682: }
1.241 deraadt 683:
1.121 markus 684: void
685: channel_cancel_cleanup(int id)
686: {
1.229 markus 687: Channel *c = channel_by_id(id);
1.180 deraadt 688:
1.121 markus 689: if (c == NULL) {
1.188 itojun 690: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 691: return;
1.52 markus 692: }
1.131 markus 693: c->detach_user = NULL;
1.225 djm 694: c->detach_close = 0;
1.121 markus 695: }
1.241 deraadt 696:
1.121 markus 697: void
1.231 reyk 698: channel_register_filter(int id, channel_infilter_fn *ifn,
699: channel_outfilter_fn *ofn)
1.121 markus 700: {
701: Channel *c = channel_lookup(id);
1.180 deraadt 702:
1.121 markus 703: if (c == NULL) {
1.188 itojun 704: logit("channel_register_filter: %d: bad id", id);
1.121 markus 705: return;
1.52 markus 706: }
1.231 reyk 707: c->input_filter = ifn;
708: c->output_filter = ofn;
1.52 markus 709: }
710:
1.49 markus 711: void
1.121 markus 712: channel_set_fds(int id, int rfd, int wfd, int efd,
1.168 markus 713: int extusage, int nonblock, u_int window_max)
1.1 deraadt 714: {
1.121 markus 715: Channel *c = channel_lookup(id);
1.180 deraadt 716:
1.121 markus 717: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
718: fatal("channel_activate for non-larval channel %d.", id);
719: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
720: c->type = SSH_CHANNEL_OPEN;
1.168 markus 721: c->local_window = c->local_window_max = window_max;
1.121 markus 722: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
723: packet_put_int(c->remote_id);
724: packet_put_int(c->local_window);
725: packet_send();
1.1 deraadt 726: }
727:
1.27 markus 728: /*
1.41 markus 729: * 'channel_pre*' are called just before select() to add any bits relevant to
730: * channels in the select bitmasks.
731: */
732: /*
733: * 'channel_post*': perform any appropriate operations for channels which
734: * have events pending.
1.27 markus 735: */
1.237 deraadt 736: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 737: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
738: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
739:
1.259 stevesk 740: /* ARGSUSED */
1.127 itojun 741: static void
1.237 deraadt 742: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 743: {
744: FD_SET(c->sock, readset);
745: }
746:
1.259 stevesk 747: /* ARGSUSED */
1.127 itojun 748: static void
1.237 deraadt 749: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 750: {
751: debug3("channel %d: waiting for connection", c->self);
752: FD_SET(c->sock, writeset);
753: }
754:
1.127 itojun 755: static void
1.237 deraadt 756: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 757: {
758: if (buffer_len(&c->input) < packet_get_maxsize())
759: FD_SET(c->sock, readset);
760: if (buffer_len(&c->output) > 0)
761: FD_SET(c->sock, writeset);
762: }
1.1 deraadt 763:
1.127 itojun 764: static void
1.237 deraadt 765: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 766: {
1.157 markus 767: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 768:
1.44 markus 769: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 770: limit > 0 &&
1.250 djm 771: buffer_len(&c->input) < limit &&
772: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 773: FD_SET(c->rfd, readset);
774: if (c->ostate == CHAN_OUTPUT_OPEN ||
775: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
776: if (buffer_len(&c->output) > 0) {
777: FD_SET(c->wfd, writeset);
778: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 779: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 780: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
781: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 782: else
783: chan_obuf_empty(c);
1.44 markus 784: }
785: }
786: /** XXX check close conditions, too */
1.157 markus 787: if (compat20 && c->efd != -1) {
1.44 markus 788: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
789: buffer_len(&c->extended) > 0)
790: FD_SET(c->efd, writeset);
1.172 markus 791: else if (!(c->flags & CHAN_EOF_SENT) &&
792: c->extended_usage == CHAN_EXTENDED_READ &&
1.44 markus 793: buffer_len(&c->extended) < c->remote_window)
794: FD_SET(c->efd, readset);
795: }
1.204 djm 796: /* XXX: What about efd? races? */
1.208 deraadt 797: if (compat20 && c->ctl_fd != -1 &&
1.204 djm 798: c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
799: FD_SET(c->ctl_fd, readset);
1.44 markus 800: }
801:
1.259 stevesk 802: /* ARGSUSED */
1.127 itojun 803: static void
1.237 deraadt 804: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 805: {
806: if (buffer_len(&c->input) == 0) {
807: packet_start(SSH_MSG_CHANNEL_CLOSE);
808: packet_put_int(c->remote_id);
809: packet_send();
810: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 811: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 812: }
813: }
814:
1.259 stevesk 815: /* ARGSUSED */
1.127 itojun 816: static void
1.237 deraadt 817: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 818: {
819: if (buffer_len(&c->output) == 0)
1.113 markus 820: chan_mark_dead(c);
1.49 markus 821: else
1.41 markus 822: FD_SET(c->sock, writeset);
823: }
824:
825: /*
826: * This is a special state for X11 authentication spoofing. An opened X11
827: * connection (when authentication spoofing is being done) remains in this
828: * state until the first packet has been completely read. The authentication
829: * data in that packet is then substituted by the real data if it matches the
830: * fake data, and the channel is put into normal mode.
1.51 markus 831: * XXX All this happens at the client side.
1.121 markus 832: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 833: */
1.127 itojun 834: static int
1.121 markus 835: x11_open_helper(Buffer *b)
1.1 deraadt 836: {
1.77 markus 837: u_char *ucp;
838: u_int proto_len, data_len;
1.25 markus 839:
1.41 markus 840: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 841: if (buffer_len(b) < 12)
1.41 markus 842: return 0;
843:
844: /* Parse the lengths of variable-length fields. */
1.155 stevesk 845: ucp = buffer_ptr(b);
1.41 markus 846: if (ucp[0] == 0x42) { /* Byte order MSB first. */
847: proto_len = 256 * ucp[6] + ucp[7];
848: data_len = 256 * ucp[8] + ucp[9];
849: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
850: proto_len = ucp[6] + 256 * ucp[7];
851: data_len = ucp[8] + 256 * ucp[9];
852: } else {
1.194 markus 853: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 854: ucp[0]);
1.41 markus 855: return -1;
856: }
857:
858: /* Check if the whole packet is in buffer. */
1.121 markus 859: if (buffer_len(b) <
1.41 markus 860: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
861: return 0;
862:
863: /* Check if authentication protocol matches. */
864: if (proto_len != strlen(x11_saved_proto) ||
865: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 866: debug2("X11 connection uses different authentication protocol.");
1.41 markus 867: return -1;
868: }
869: /* Check if authentication data matches our fake data. */
870: if (data_len != x11_fake_data_len ||
871: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
872: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 873: debug2("X11 auth data does not match fake data.");
1.41 markus 874: return -1;
875: }
876: /* Check fake data length */
877: if (x11_fake_data_len != x11_saved_data_len) {
878: error("X11 fake_data_len %d != saved_data_len %d",
879: x11_fake_data_len, x11_saved_data_len);
880: return -1;
881: }
882: /*
883: * Received authentication protocol and data match
884: * our fake data. Substitute the fake data with real
885: * data.
886: */
887: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
888: x11_saved_data, x11_saved_data_len);
889: return 1;
890: }
891:
1.127 itojun 892: static void
1.237 deraadt 893: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 894: {
1.121 markus 895: int ret = x11_open_helper(&c->output);
1.180 deraadt 896:
1.41 markus 897: if (ret == 1) {
898: /* Start normal processing for the channel. */
899: c->type = SSH_CHANNEL_OPEN;
1.47 markus 900: channel_pre_open_13(c, readset, writeset);
1.41 markus 901: } else if (ret == -1) {
902: /*
903: * We have received an X11 connection that has bad
904: * authentication information.
905: */
1.188 itojun 906: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 907: buffer_clear(&c->input);
908: buffer_clear(&c->output);
1.132 markus 909: channel_close_fd(&c->sock);
1.41 markus 910: c->sock = -1;
911: c->type = SSH_CHANNEL_CLOSED;
912: packet_start(SSH_MSG_CHANNEL_CLOSE);
913: packet_put_int(c->remote_id);
914: packet_send();
915: }
916: }
1.25 markus 917:
1.127 itojun 918: static void
1.237 deraadt 919: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 920: {
1.121 markus 921: int ret = x11_open_helper(&c->output);
1.133 markus 922:
923: /* c->force_drain = 1; */
924:
1.41 markus 925: if (ret == 1) {
926: c->type = SSH_CHANNEL_OPEN;
1.157 markus 927: channel_pre_open(c, readset, writeset);
1.41 markus 928: } else if (ret == -1) {
1.188 itojun 929: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 930: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 931: chan_read_failed(c);
932: buffer_clear(&c->input);
933: chan_ibuf_empty(c);
934: buffer_clear(&c->output);
935: /* for proto v1, the peer will send an IEOF */
936: if (compat20)
937: chan_write_failed(c);
938: else
939: c->type = SSH_CHANNEL_OPEN;
1.194 markus 940: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 941: }
942: }
1.25 markus 943:
1.104 markus 944: /* try to decode a socks4 header */
1.259 stevesk 945: /* ARGSUSED */
1.127 itojun 946: static int
1.237 deraadt 947: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 948: {
1.181 markus 949: char *p, *host;
1.217 djm 950: u_int len, have, i, found;
1.148 deraadt 951: char username[256];
1.103 markus 952: struct {
953: u_int8_t version;
954: u_int8_t command;
955: u_int16_t dest_port;
1.104 markus 956: struct in_addr dest_addr;
1.103 markus 957: } s4_req, s4_rsp;
958:
1.104 markus 959: debug2("channel %d: decode socks4", c->self);
1.109 markus 960:
961: have = buffer_len(&c->input);
962: len = sizeof(s4_req);
963: if (have < len)
964: return 0;
965: p = buffer_ptr(&c->input);
966: for (found = 0, i = len; i < have; i++) {
967: if (p[i] == '\0') {
968: found = 1;
969: break;
970: }
971: if (i > 1024) {
972: /* the peer is probably sending garbage */
973: debug("channel %d: decode socks4: too long",
974: c->self);
975: return -1;
976: }
977: }
978: if (!found)
979: return 0;
1.103 markus 980: buffer_get(&c->input, (char *)&s4_req.version, 1);
981: buffer_get(&c->input, (char *)&s4_req.command, 1);
982: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 983: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 984: have = buffer_len(&c->input);
1.103 markus 985: p = buffer_ptr(&c->input);
986: len = strlen(p);
1.106 markus 987: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.103 markus 988: if (len > have)
1.104 markus 989: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 990: c->self, len, have);
991: strlcpy(username, p, sizeof(username));
992: buffer_consume(&c->input, len);
993: buffer_consume(&c->input, 1); /* trailing '\0' */
994:
1.104 markus 995: host = inet_ntoa(s4_req.dest_addr);
1.103 markus 996: strlcpy(c->path, host, sizeof(c->path));
997: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 998:
1.194 markus 999: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.106 markus 1000: c->self, host, c->host_port, s4_req.command);
1.103 markus 1001:
1.104 markus 1002: if (s4_req.command != 1) {
1003: debug("channel %d: cannot handle: socks4 cn %d",
1004: c->self, s4_req.command);
1005: return -1;
1.103 markus 1006: }
1.104 markus 1007: s4_rsp.version = 0; /* vn: 0 for reply */
1008: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1009: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1010: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1011: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1012: return 1;
1013: }
1014:
1.193 markus 1015: /* try to decode a socks5 header */
1016: #define SSH_SOCKS5_AUTHDONE 0x1000
1017: #define SSH_SOCKS5_NOAUTH 0x00
1018: #define SSH_SOCKS5_IPV4 0x01
1019: #define SSH_SOCKS5_DOMAIN 0x03
1020: #define SSH_SOCKS5_IPV6 0x04
1021: #define SSH_SOCKS5_CONNECT 0x01
1022: #define SSH_SOCKS5_SUCCESS 0x00
1023:
1.259 stevesk 1024: /* ARGSUSED */
1.193 markus 1025: static int
1.237 deraadt 1026: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1027: {
1028: struct {
1029: u_int8_t version;
1030: u_int8_t command;
1031: u_int8_t reserved;
1032: u_int8_t atyp;
1033: } s5_req, s5_rsp;
1034: u_int16_t dest_port;
1035: u_char *p, dest_addr[255+1];
1.252 djm 1036: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1037:
1038: debug2("channel %d: decode socks5", c->self);
1039: p = buffer_ptr(&c->input);
1040: if (p[0] != 0x05)
1041: return -1;
1042: have = buffer_len(&c->input);
1043: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1044: /* format: ver | nmethods | methods */
1.198 djm 1045: if (have < 2)
1.193 markus 1046: return 0;
1047: nmethods = p[1];
1048: if (have < nmethods + 2)
1049: return 0;
1050: /* look for method: "NO AUTHENTICATION REQUIRED" */
1051: for (found = 0, i = 2 ; i < nmethods + 2; i++) {
1052: if (p[i] == SSH_SOCKS5_NOAUTH ) {
1053: found = 1;
1054: break;
1055: }
1056: }
1057: if (!found) {
1058: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1059: c->self);
1060: return -1;
1061: }
1062: buffer_consume(&c->input, nmethods + 2);
1063: buffer_put_char(&c->output, 0x05); /* version */
1064: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1065: FD_SET(c->sock, writeset);
1066: c->flags |= SSH_SOCKS5_AUTHDONE;
1067: debug2("channel %d: socks5 auth done", c->self);
1068: return 0; /* need more */
1069: }
1070: debug2("channel %d: socks5 post auth", c->self);
1071: if (have < sizeof(s5_req)+1)
1072: return 0; /* need more */
1.247 deraadt 1073: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1074: if (s5_req.version != 0x05 ||
1075: s5_req.command != SSH_SOCKS5_CONNECT ||
1076: s5_req.reserved != 0x00) {
1.194 markus 1077: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1078: return -1;
1079: }
1.213 deraadt 1080: switch (s5_req.atyp){
1.193 markus 1081: case SSH_SOCKS5_IPV4:
1082: addrlen = 4;
1083: af = AF_INET;
1084: break;
1085: case SSH_SOCKS5_DOMAIN:
1086: addrlen = p[sizeof(s5_req)];
1087: af = -1;
1088: break;
1089: case SSH_SOCKS5_IPV6:
1090: addrlen = 16;
1091: af = AF_INET6;
1092: break;
1093: default:
1.194 markus 1094: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1095: return -1;
1096: }
1.252 djm 1097: need = sizeof(s5_req) + addrlen + 2;
1098: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1099: need++;
1100: if (have < need)
1.193 markus 1101: return 0;
1102: buffer_consume(&c->input, sizeof(s5_req));
1103: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1104: buffer_consume(&c->input, 1); /* host string length */
1105: buffer_get(&c->input, (char *)&dest_addr, addrlen);
1106: buffer_get(&c->input, (char *)&dest_port, 2);
1107: dest_addr[addrlen] = '\0';
1108: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1.201 deraadt 1109: strlcpy(c->path, (char *)dest_addr, sizeof(c->path));
1.193 markus 1110: else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL)
1111: return -1;
1112: c->host_port = ntohs(dest_port);
1.198 djm 1113:
1.194 markus 1114: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1115: c->self, c->path, c->host_port, s5_req.command);
1116:
1117: s5_rsp.version = 0x05;
1118: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1119: s5_rsp.reserved = 0; /* ignored */
1120: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1121: ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1122: dest_port = 0; /* ignored */
1123:
1.246 deraadt 1124: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1125: buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1126: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1127: return 1;
1128: }
1129:
1.104 markus 1130: /* dynamic port forwarding */
1.127 itojun 1131: static void
1.237 deraadt 1132: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1133: {
1134: u_char *p;
1.217 djm 1135: u_int have;
1136: int ret;
1.103 markus 1137:
1.104 markus 1138: have = buffer_len(&c->input);
1.137 markus 1139: c->delayed = 0;
1.104 markus 1140: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1141: /* buffer_dump(&c->input); */
1.104 markus 1142: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1143: if (have < 3) {
1.104 markus 1144: /* need more */
1145: FD_SET(c->sock, readset);
1146: return;
1147: }
1148: /* try to guess the protocol */
1149: p = buffer_ptr(&c->input);
1150: switch (p[0]) {
1151: case 0x04:
1152: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1153: break;
1154: case 0x05:
1155: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1156: break;
1157: default:
1158: ret = -1;
1159: break;
1160: }
1161: if (ret < 0) {
1.113 markus 1162: chan_mark_dead(c);
1.104 markus 1163: } else if (ret == 0) {
1164: debug2("channel %d: pre_dynamic: need more", c->self);
1165: /* need more */
1166: FD_SET(c->sock, readset);
1167: } else {
1168: /* switch to the next state */
1169: c->type = SSH_CHANNEL_OPENING;
1170: port_open_helper(c, "direct-tcpip");
1171: }
1.103 markus 1172: }
1173:
1.41 markus 1174: /* This is our fake X11 server socket. */
1.259 stevesk 1175: /* ARGSUSED */
1.127 itojun 1176: static void
1.237 deraadt 1177: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1178: {
1.113 markus 1179: Channel *nc;
1.41 markus 1180: struct sockaddr addr;
1.162 stevesk 1181: int newsock;
1.41 markus 1182: socklen_t addrlen;
1.85 markus 1183: char buf[16384], *remote_ipaddr;
1.51 markus 1184: int remote_port;
1.25 markus 1185:
1.41 markus 1186: if (FD_ISSET(c->sock, readset)) {
1187: debug("X11 connection requested.");
1188: addrlen = sizeof(addr);
1189: newsock = accept(c->sock, &addr, &addrlen);
1.149 markus 1190: if (c->single_connection) {
1.194 markus 1191: debug2("single_connection: closing X11 listener.");
1.149 markus 1192: channel_close_fd(&c->sock);
1193: chan_mark_dead(c);
1194: }
1.41 markus 1195: if (newsock < 0) {
1196: error("accept: %.100s", strerror(errno));
1197: return;
1198: }
1.162 stevesk 1199: set_nodelay(newsock);
1.85 markus 1200: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1201: remote_port = get_peer_port(newsock);
1.41 markus 1202: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1203: remote_ipaddr, remote_port);
1.51 markus 1204:
1.113 markus 1205: nc = channel_new("accepted x11 socket",
1.51 markus 1206: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1207: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1208: if (compat20) {
1209: packet_start(SSH2_MSG_CHANNEL_OPEN);
1210: packet_put_cstring("x11");
1.113 markus 1211: packet_put_int(nc->self);
1.149 markus 1212: packet_put_int(nc->local_window_max);
1213: packet_put_int(nc->local_maxpacket);
1.85 markus 1214: /* originator ipaddr and port */
1215: packet_put_cstring(remote_ipaddr);
1.57 markus 1216: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1217: debug2("ssh2 x11 bug compat mode");
1.57 markus 1218: } else {
1219: packet_put_int(remote_port);
1220: }
1.51 markus 1221: packet_send();
1222: } else {
1223: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1224: packet_put_int(nc->self);
1.121 markus 1225: if (packet_get_protocol_flags() &
1226: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1227: packet_put_cstring(buf);
1.51 markus 1228: packet_send();
1229: }
1.85 markus 1230: xfree(remote_ipaddr);
1.41 markus 1231: }
1232: }
1.25 markus 1233:
1.127 itojun 1234: static void
1.103 markus 1235: port_open_helper(Channel *c, char *rtype)
1236: {
1237: int direct;
1238: char buf[1024];
1239: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1240: int remote_port = get_peer_port(c->sock);
1.103 markus 1241:
1242: direct = (strcmp(rtype, "direct-tcpip") == 0);
1243:
1244: snprintf(buf, sizeof buf,
1245: "%s: listening port %d for %.100s port %d, "
1246: "connect from %.200s port %d",
1247: rtype, c->listening_port, c->path, c->host_port,
1248: remote_ipaddr, remote_port);
1249:
1250: xfree(c->remote_name);
1251: c->remote_name = xstrdup(buf);
1252:
1253: if (compat20) {
1254: packet_start(SSH2_MSG_CHANNEL_OPEN);
1255: packet_put_cstring(rtype);
1256: packet_put_int(c->self);
1257: packet_put_int(c->local_window_max);
1258: packet_put_int(c->local_maxpacket);
1259: if (direct) {
1260: /* target host, port */
1261: packet_put_cstring(c->path);
1262: packet_put_int(c->host_port);
1263: } else {
1264: /* listen address, port */
1265: packet_put_cstring(c->path);
1266: packet_put_int(c->listening_port);
1267: }
1268: /* originator host and port */
1269: packet_put_cstring(remote_ipaddr);
1.216 markus 1270: packet_put_int((u_int)remote_port);
1.103 markus 1271: packet_send();
1272: } else {
1273: packet_start(SSH_MSG_PORT_OPEN);
1274: packet_put_int(c->self);
1275: packet_put_cstring(c->path);
1276: packet_put_int(c->host_port);
1.121 markus 1277: if (packet_get_protocol_flags() &
1278: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1279: packet_put_cstring(c->remote_name);
1280: packet_send();
1281: }
1282: xfree(remote_ipaddr);
1283: }
1284:
1.226 djm 1285: static void
1286: channel_set_reuseaddr(int fd)
1287: {
1288: int on = 1;
1289:
1290: /*
1291: * Set socket options.
1292: * Allow local port reuse in TIME_WAIT.
1293: */
1294: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1295: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1296: }
1297:
1.41 markus 1298: /*
1299: * This socket is listening for connections to a forwarded TCP/IP port.
1300: */
1.259 stevesk 1301: /* ARGSUSED */
1.127 itojun 1302: static void
1.237 deraadt 1303: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1304: {
1.103 markus 1305: Channel *nc;
1.41 markus 1306: struct sockaddr addr;
1.113 markus 1307: int newsock, nextstate;
1.41 markus 1308: socklen_t addrlen;
1.103 markus 1309: char *rtype;
1.73 markus 1310:
1.41 markus 1311: if (FD_ISSET(c->sock, readset)) {
1312: debug("Connection to port %d forwarding "
1313: "to %.100s port %d requested.",
1314: c->listening_port, c->path, c->host_port);
1.103 markus 1315:
1.137 markus 1316: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1317: nextstate = SSH_CHANNEL_OPENING;
1318: rtype = "forwarded-tcpip";
1319: } else {
1320: if (c->host_port == 0) {
1321: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1322: rtype = "dynamic-tcpip";
1.137 markus 1323: } else {
1324: nextstate = SSH_CHANNEL_OPENING;
1325: rtype = "direct-tcpip";
1326: }
1327: }
1.103 markus 1328:
1.41 markus 1329: addrlen = sizeof(addr);
1330: newsock = accept(c->sock, &addr, &addrlen);
1331: if (newsock < 0) {
1332: error("accept: %.100s", strerror(errno));
1333: return;
1334: }
1.169 stevesk 1335: set_nodelay(newsock);
1.190 markus 1336: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1337: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1338: nc->listening_port = c->listening_port;
1339: nc->host_port = c->host_port;
1340: strlcpy(nc->path, c->path, sizeof(nc->path));
1341:
1.137 markus 1342: if (nextstate == SSH_CHANNEL_DYNAMIC) {
1343: /*
1344: * do not call the channel_post handler until
1345: * this flag has been reset by a pre-handler.
1346: * otherwise the FD_ISSET calls might overflow
1347: */
1348: nc->delayed = 1;
1349: } else {
1.103 markus 1350: port_open_helper(nc, rtype);
1.137 markus 1351: }
1.41 markus 1352: }
1353: }
1.25 markus 1354:
1.41 markus 1355: /*
1356: * This is the authentication agent socket listening for connections from
1357: * clients.
1358: */
1.259 stevesk 1359: /* ARGSUSED */
1.127 itojun 1360: static void
1.237 deraadt 1361: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1362: {
1.113 markus 1363: Channel *nc;
1364: int newsock;
1.41 markus 1365: struct sockaddr addr;
1366: socklen_t addrlen;
1.25 markus 1367:
1.41 markus 1368: if (FD_ISSET(c->sock, readset)) {
1369: addrlen = sizeof(addr);
1370: newsock = accept(c->sock, &addr, &addrlen);
1371: if (newsock < 0) {
1372: error("accept from auth socket: %.100s", strerror(errno));
1373: return;
1374: }
1.113 markus 1375: nc = channel_new("accepted auth socket",
1.73 markus 1376: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1377: c->local_window_max, c->local_maxpacket,
1.190 markus 1378: 0, "accepted auth socket", 1);
1.73 markus 1379: if (compat20) {
1380: packet_start(SSH2_MSG_CHANNEL_OPEN);
1381: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1382: packet_put_int(nc->self);
1.73 markus 1383: packet_put_int(c->local_window_max);
1384: packet_put_int(c->local_maxpacket);
1385: } else {
1386: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1387: packet_put_int(nc->self);
1.73 markus 1388: }
1.41 markus 1389: packet_send();
1390: }
1391: }
1.25 markus 1392:
1.259 stevesk 1393: /* ARGSUSED */
1.127 itojun 1394: static void
1.237 deraadt 1395: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1396: {
1.114 markus 1397: int err = 0;
1.129 stevesk 1398: socklen_t sz = sizeof(err);
1.114 markus 1399:
1.75 markus 1400: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1401: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1402: err = errno;
1403: error("getsockopt SO_ERROR failed");
1404: }
1405: if (err == 0) {
1406: debug("channel %d: connected", c->self);
1407: c->type = SSH_CHANNEL_OPEN;
1408: if (compat20) {
1409: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1410: packet_put_int(c->remote_id);
1411: packet_put_int(c->self);
1412: packet_put_int(c->local_window);
1413: packet_put_int(c->local_maxpacket);
1414: } else {
1415: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1416: packet_put_int(c->remote_id);
1417: packet_put_int(c->self);
1418: }
1.75 markus 1419: } else {
1.114 markus 1420: debug("channel %d: not connected: %s",
1421: c->self, strerror(err));
1422: if (compat20) {
1423: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1424: packet_put_int(c->remote_id);
1425: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1426: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1427: packet_put_cstring(strerror(err));
1428: packet_put_cstring("");
1429: }
1.75 markus 1430: } else {
1.114 markus 1431: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1432: packet_put_int(c->remote_id);
1.75 markus 1433: }
1.114 markus 1434: chan_mark_dead(c);
1.75 markus 1435: }
1.114 markus 1436: packet_send();
1.75 markus 1437: }
1438: }
1439:
1.259 stevesk 1440: /* ARGSUSED */
1.127 itojun 1441: static int
1.237 deraadt 1442: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1443: {
1.214 markus 1444: char buf[CHAN_RBUF];
1.41 markus 1445: int len;
1.25 markus 1446:
1.118 markus 1447: if (c->rfd != -1 &&
1.41 markus 1448: FD_ISSET(c->rfd, readset)) {
1449: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1450: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1451: return 1;
1.41 markus 1452: if (len <= 0) {
1.194 markus 1453: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1454: c->self, c->rfd, len);
1.104 markus 1455: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1456: debug2("channel %d: not open", c->self);
1.113 markus 1457: chan_mark_dead(c);
1.103 markus 1458: return -1;
1.104 markus 1459: } else if (compat13) {
1.158 markus 1460: buffer_clear(&c->output);
1.41 markus 1461: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1462: debug2("channel %d: input draining.", c->self);
1.25 markus 1463: } else {
1.41 markus 1464: chan_read_failed(c);
1.25 markus 1465: }
1.41 markus 1466: return -1;
1467: }
1.143 deraadt 1468: if (c->input_filter != NULL) {
1.66 markus 1469: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1470: debug2("channel %d: filter stops", c->self);
1.65 markus 1471: chan_read_failed(c);
1472: }
1.228 reyk 1473: } else if (c->datagram) {
1474: buffer_put_string(&c->input, buf, len);
1.65 markus 1475: } else {
1476: buffer_append(&c->input, buf, len);
1477: }
1.41 markus 1478: }
1479: return 1;
1480: }
1.241 deraadt 1481:
1.259 stevesk 1482: /* ARGSUSED */
1.127 itojun 1483: static int
1.237 deraadt 1484: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1485: {
1.95 markus 1486: struct termios tio;
1.231 reyk 1487: u_char *data = NULL, *buf;
1.134 markus 1488: u_int dlen;
1.41 markus 1489: int len;
1.25 markus 1490:
1.41 markus 1491: /* Send buffered output data to the socket. */
1.118 markus 1492: if (c->wfd != -1 &&
1.41 markus 1493: FD_ISSET(c->wfd, writeset) &&
1494: buffer_len(&c->output) > 0) {
1.231 reyk 1495: if (c->output_filter != NULL) {
1496: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1497: debug2("channel %d: filter stops", c->self);
1.232 reyk 1498: if (c->type != SSH_CHANNEL_OPEN)
1499: chan_mark_dead(c);
1500: else
1501: chan_write_failed(c);
1502: return -1;
1.231 reyk 1503: }
1504: } else if (c->datagram) {
1505: buf = data = buffer_get_string(&c->output, &dlen);
1506: } else {
1507: buf = data = buffer_ptr(&c->output);
1508: dlen = buffer_len(&c->output);
1509: }
1510:
1.228 reyk 1511: if (c->datagram) {
1512: /* ignore truncated writes, datagrams might get lost */
1513: c->local_consumed += dlen + 4;
1.231 reyk 1514: len = write(c->wfd, buf, dlen);
1.228 reyk 1515: xfree(data);
1516: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1517: return 1;
1518: if (len <= 0) {
1519: if (c->type != SSH_CHANNEL_OPEN)
1520: chan_mark_dead(c);
1521: else
1522: chan_write_failed(c);
1523: return -1;
1524: }
1525: return 1;
1526: }
1.231 reyk 1527:
1528: len = write(c->wfd, buf, dlen);
1.53 markus 1529: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1530: return 1;
1.41 markus 1531: if (len <= 0) {
1.104 markus 1532: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1533: debug2("channel %d: not open", c->self);
1.113 markus 1534: chan_mark_dead(c);
1.104 markus 1535: return -1;
1536: } else if (compat13) {
1.158 markus 1537: buffer_clear(&c->output);
1.194 markus 1538: debug2("channel %d: input draining.", c->self);
1.41 markus 1539: c->type = SSH_CHANNEL_INPUT_DRAINING;
1540: } else {
1541: chan_write_failed(c);
1542: }
1543: return -1;
1.91 markus 1544: }
1.231 reyk 1545: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1546: if (tcgetattr(c->wfd, &tio) == 0 &&
1547: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1548: /*
1549: * Simulate echo to reduce the impact of
1.96 markus 1550: * traffic analysis. We need to match the
1.95 markus 1551: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1552: * (4 byte channel id + buf)
1.91 markus 1553: */
1.95 markus 1554: packet_send_ignore(4 + len);
1.91 markus 1555: packet_send();
1556: }
1.25 markus 1557: }
1.41 markus 1558: buffer_consume(&c->output, len);
1.44 markus 1559: if (compat20 && len > 0) {
1560: c->local_consumed += len;
1561: }
1562: }
1563: return 1;
1564: }
1.241 deraadt 1565:
1.127 itojun 1566: static int
1.237 deraadt 1567: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1568: {
1.214 markus 1569: char buf[CHAN_RBUF];
1.44 markus 1570: int len;
1571:
1.45 markus 1572: /** XXX handle drain efd, too */
1.44 markus 1573: if (c->efd != -1) {
1574: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1575: FD_ISSET(c->efd, writeset) &&
1576: buffer_len(&c->extended) > 0) {
1577: len = write(c->efd, buffer_ptr(&c->extended),
1578: buffer_len(&c->extended));
1.70 markus 1579: debug2("channel %d: written %d to efd %d",
1.44 markus 1580: c->self, len, c->efd);
1.93 markus 1581: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1582: return 1;
1583: if (len <= 0) {
1584: debug2("channel %d: closing write-efd %d",
1585: c->self, c->efd);
1.132 markus 1586: channel_close_fd(&c->efd);
1.93 markus 1587: } else {
1.44 markus 1588: buffer_consume(&c->extended, len);
1589: c->local_consumed += len;
1590: }
1591: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1592: FD_ISSET(c->efd, readset)) {
1593: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1594: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1595: c->self, len, c->efd);
1.93 markus 1596: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1597: return 1;
1598: if (len <= 0) {
1599: debug2("channel %d: closing read-efd %d",
1.45 markus 1600: c->self, c->efd);
1.132 markus 1601: channel_close_fd(&c->efd);
1.93 markus 1602: } else {
1.44 markus 1603: buffer_append(&c->extended, buf, len);
1.93 markus 1604: }
1.44 markus 1605: }
1606: }
1607: return 1;
1608: }
1.241 deraadt 1609:
1.259 stevesk 1610: /* ARGSUSED */
1.127 itojun 1611: static int
1.237 deraadt 1612: channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
1.204 djm 1613: {
1614: char buf[16];
1615: int len;
1616:
1617: /* Monitor control fd to detect if the slave client exits */
1618: if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1619: len = read(c->ctl_fd, buf, sizeof(buf));
1620: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1621: return 1;
1622: if (len <= 0) {
1623: debug2("channel %d: ctl read<=0", c->self);
1624: if (c->type != SSH_CHANNEL_OPEN) {
1625: debug2("channel %d: not open", c->self);
1626: chan_mark_dead(c);
1627: return -1;
1628: } else {
1629: chan_read_failed(c);
1630: chan_write_failed(c);
1631: }
1632: return -1;
1633: } else
1634: fatal("%s: unexpected data on ctl fd", __func__);
1635: }
1636: return 1;
1637: }
1.241 deraadt 1638:
1.204 djm 1639: static int
1.93 markus 1640: channel_check_window(Channel *c)
1.44 markus 1641: {
1.104 markus 1642: if (c->type == SSH_CHANNEL_OPEN &&
1643: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.44 markus 1644: c->local_window < c->local_window_max/2 &&
1645: c->local_consumed > 0) {
1646: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1647: packet_put_int(c->remote_id);
1648: packet_put_int(c->local_consumed);
1649: packet_send();
1.70 markus 1650: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1651: c->self, c->local_window,
1652: c->local_consumed);
1653: c->local_window += c->local_consumed;
1654: c->local_consumed = 0;
1.1 deraadt 1655: }
1.41 markus 1656: return 1;
1.1 deraadt 1657: }
1658:
1.127 itojun 1659: static void
1.237 deraadt 1660: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1661: {
1.137 markus 1662: if (c->delayed)
1663: return;
1.41 markus 1664: channel_handle_rfd(c, readset, writeset);
1665: channel_handle_wfd(c, readset, writeset);
1.157 markus 1666: if (!compat20)
1.137 markus 1667: return;
1.44 markus 1668: channel_handle_efd(c, readset, writeset);
1.204 djm 1669: channel_handle_ctl(c, readset, writeset);
1.93 markus 1670: channel_check_window(c);
1.44 markus 1671: }
1672:
1.259 stevesk 1673: /* ARGSUSED */
1.127 itojun 1674: static void
1.237 deraadt 1675: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1676: {
1.41 markus 1677: int len;
1.180 deraadt 1678:
1.41 markus 1679: /* Send buffered output data to the socket. */
1680: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1681: len = write(c->sock, buffer_ptr(&c->output),
1682: buffer_len(&c->output));
1683: if (len <= 0)
1.158 markus 1684: buffer_clear(&c->output);
1.41 markus 1685: else
1686: buffer_consume(&c->output, len);
1687: }
1688: }
1.25 markus 1689:
1.127 itojun 1690: static void
1.44 markus 1691: channel_handler_init_20(void)
1692: {
1.157 markus 1693: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1694: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1695: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1696: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1697: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1698: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1699: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1700: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1701:
1.157 markus 1702: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1703: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1704: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1705: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1706: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1707: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1708: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1709: }
1710:
1.127 itojun 1711: static void
1.41 markus 1712: channel_handler_init_13(void)
1713: {
1714: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1715: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1716: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1717: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1718: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1719: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1720: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1721: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1722: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1723:
1.157 markus 1724: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1725: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1726: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1727: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1728: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1729: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1730: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1731: }
1.25 markus 1732:
1.127 itojun 1733: static void
1.41 markus 1734: channel_handler_init_15(void)
1735: {
1.157 markus 1736: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1737: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1738: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1739: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1740: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1741: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1742: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1743:
1.41 markus 1744: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1745: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1746: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1747: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1748: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1749: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1750: }
1.27 markus 1751:
1.127 itojun 1752: static void
1.41 markus 1753: channel_handler_init(void)
1754: {
1755: int i;
1.180 deraadt 1756:
1.148 deraadt 1757: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1758: channel_pre[i] = NULL;
1759: channel_post[i] = NULL;
1760: }
1.44 markus 1761: if (compat20)
1762: channel_handler_init_20();
1763: else if (compat13)
1.41 markus 1764: channel_handler_init_13();
1765: else
1766: channel_handler_init_15();
1767: }
1.25 markus 1768:
1.140 markus 1769: /* gc dead channels */
1770: static void
1771: channel_garbage_collect(Channel *c)
1772: {
1773: if (c == NULL)
1774: return;
1775: if (c->detach_user != NULL) {
1.225 djm 1776: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1777: return;
1.194 markus 1778: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1779: c->detach_user(c->self, NULL);
1780: /* if we still have a callback */
1781: if (c->detach_user != NULL)
1782: return;
1.194 markus 1783: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1784: }
1785: if (!chan_is_dead(c, 1))
1786: return;
1.194 markus 1787: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1788: channel_free(c);
1789: }
1790:
1.127 itojun 1791: static void
1.237 deraadt 1792: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
1.41 markus 1793: {
1794: static int did_init = 0;
1.209 avsm 1795: u_int i;
1.41 markus 1796: Channel *c;
1.25 markus 1797:
1.41 markus 1798: if (!did_init) {
1799: channel_handler_init();
1800: did_init = 1;
1801: }
1802: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1803: c = channels[i];
1804: if (c == NULL)
1.41 markus 1805: continue;
1.118 markus 1806: if (ftab[c->type] != NULL)
1807: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1808: channel_garbage_collect(c);
1.1 deraadt 1809: }
1810: }
1811:
1.121 markus 1812: /*
1813: * Allocate/update select bitmasks and add any bits relevant to channels in
1814: * select bitmasks.
1815: */
1.49 markus 1816: void
1.100 markus 1817: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.209 avsm 1818: u_int *nallocp, int rekeying)
1.41 markus 1819: {
1.243 djm 1820: u_int n, sz, nfdset;
1.84 markus 1821:
1822: n = MAX(*maxfdp, channel_max_fd);
1823:
1.243 djm 1824: nfdset = howmany(n+1, NFDBITS);
1825: /* Explicitly test here, because xrealloc isn't always called */
1826: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1827: fatal("channel_prepare_select: max_fd (%d) is too large", n);
1828: sz = nfdset * sizeof(fd_mask);
1829:
1.132 markus 1830: /* perhaps check sz < nalloc/2 and shrink? */
1831: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 1832: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1833: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 1834: *nallocp = sz;
1.84 markus 1835: }
1.132 markus 1836: *maxfdp = n;
1.84 markus 1837: memset(*readsetp, 0, sz);
1838: memset(*writesetp, 0, sz);
1839:
1.100 markus 1840: if (!rekeying)
1841: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1842: }
1843:
1.121 markus 1844: /*
1845: * After select, perform any appropriate operations for channels which have
1846: * events pending.
1847: */
1.49 markus 1848: void
1.237 deraadt 1849: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 1850: {
1851: channel_handler(channel_post, readset, writeset);
1852: }
1853:
1.121 markus 1854:
1.84 markus 1855: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 1856: void
1.142 itojun 1857: channel_output_poll(void)
1.1 deraadt 1858: {
1.41 markus 1859: Channel *c;
1.209 avsm 1860: u_int i, len;
1.1 deraadt 1861:
1.25 markus 1862: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1863: c = channels[i];
1864: if (c == NULL)
1865: continue;
1.37 markus 1866:
1.121 markus 1867: /*
1868: * We are only interested in channels that can have buffered
1869: * incoming data.
1870: */
1.37 markus 1871: if (compat13) {
1.41 markus 1872: if (c->type != SSH_CHANNEL_OPEN &&
1873: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1874: continue;
1875: } else {
1.41 markus 1876: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 1877: continue;
1878: }
1.46 markus 1879: if (compat20 &&
1880: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 1881: /* XXX is this true? */
1.140 markus 1882: debug3("channel %d: will not send data after close", c->self);
1.44 markus 1883: continue;
1884: }
1.25 markus 1885:
1886: /* Get the amount of buffered data for this channel. */
1.93 markus 1887: if ((c->istate == CHAN_INPUT_OPEN ||
1888: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1889: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 1890: if (c->datagram) {
1891: if (len > 0) {
1892: u_char *data;
1893: u_int dlen;
1894:
1895: data = buffer_get_string(&c->input,
1896: &dlen);
1897: packet_start(SSH2_MSG_CHANNEL_DATA);
1898: packet_put_int(c->remote_id);
1899: packet_put_string(data, dlen);
1900: packet_send();
1901: c->remote_window -= dlen + 4;
1902: xfree(data);
1903: }
1904: continue;
1905: }
1.121 markus 1906: /*
1907: * Send some data for the other side over the secure
1908: * connection.
1909: */
1.44 markus 1910: if (compat20) {
1911: if (len > c->remote_window)
1912: len = c->remote_window;
1913: if (len > c->remote_maxpacket)
1914: len = c->remote_maxpacket;
1.25 markus 1915: } else {
1.44 markus 1916: if (packet_is_interactive()) {
1917: if (len > 1024)
1918: len = 512;
1919: } else {
1920: /* Keep the packets at reasonable size. */
1921: if (len > packet_get_maxsize()/2)
1922: len = packet_get_maxsize()/2;
1923: }
1.25 markus 1924: }
1.41 markus 1925: if (len > 0) {
1.44 markus 1926: packet_start(compat20 ?
1927: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 1928: packet_put_int(c->remote_id);
1929: packet_put_string(buffer_ptr(&c->input), len);
1930: packet_send();
1931: buffer_consume(&c->input, len);
1932: c->remote_window -= len;
1933: }
1934: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 1935: if (compat13)
1936: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 1937: /*
1938: * input-buffer is empty and read-socket shutdown:
1.172 markus 1939: * tell peer, that we will not send more data: send IEOF.
1940: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 1941: */
1.172 markus 1942: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 1943: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
1944: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 1945: else
1946: chan_ibuf_empty(c);
1.25 markus 1947: }
1.44 markus 1948: /* Send extended data, i.e. stderr */
1949: if (compat20 &&
1.172 markus 1950: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 1951: c->remote_window > 0 &&
1952: (len = buffer_len(&c->extended)) > 0 &&
1953: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 1954: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 1955: c->self, c->remote_window, buffer_len(&c->extended),
1956: c->extended_usage);
1.44 markus 1957: if (len > c->remote_window)
1958: len = c->remote_window;
1959: if (len > c->remote_maxpacket)
1960: len = c->remote_maxpacket;
1961: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1962: packet_put_int(c->remote_id);
1963: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1964: packet_put_string(buffer_ptr(&c->extended), len);
1965: packet_send();
1966: buffer_consume(&c->extended, len);
1967: c->remote_window -= len;
1.93 markus 1968: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 1969: }
1.25 markus 1970: }
1.1 deraadt 1971: }
1972:
1.121 markus 1973:
1974: /* -- protocol input */
1.249 djm 1975:
1976: /* ARGSUSED */
1.49 markus 1977: void
1.154 markus 1978: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 1979: {
1.37 markus 1980: int id;
1.25 markus 1981: char *data;
1.77 markus 1982: u_int data_len;
1.41 markus 1983: Channel *c;
1.25 markus 1984:
1985: /* Get the channel number and verify it. */
1.37 markus 1986: id = packet_get_int();
1.41 markus 1987: c = channel_lookup(id);
1988: if (c == NULL)
1.37 markus 1989: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 1990:
1991: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 1992: if (c->type != SSH_CHANNEL_OPEN &&
1993: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 1994: return;
1995:
1.25 markus 1996: /* Get the data. */
1997: data = packet_get_string(&data_len);
1.200 markus 1998:
1999: /*
2000: * Ignore data for protocol > 1.3 if output end is no longer open.
2001: * For protocol 2 the sending side is reducing its window as it sends
2002: * data, so we must 'fake' consumption of the data in order to ensure
2003: * that window updates are sent back. Otherwise the connection might
2004: * deadlock.
2005: */
2006: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2007: if (compat20) {
2008: c->local_window -= data_len;
2009: c->local_consumed += data_len;
2010: }
2011: xfree(data);
2012: return;
2013: }
1.41 markus 2014:
1.143 deraadt 2015: if (compat20) {
1.44 markus 2016: if (data_len > c->local_maxpacket) {
1.188 itojun 2017: logit("channel %d: rcvd big packet %d, maxpack %d",
1.44 markus 2018: c->self, data_len, c->local_maxpacket);
2019: }
2020: if (data_len > c->local_window) {
1.188 itojun 2021: logit("channel %d: rcvd too much data %d, win %d",
1.44 markus 2022: c->self, data_len, c->local_window);
2023: xfree(data);
2024: return;
2025: }
2026: c->local_window -= data_len;
2027: }
1.152 markus 2028: packet_check_eom();
1.228 reyk 2029: if (c->datagram)
2030: buffer_put_string(&c->output, data, data_len);
2031: else
2032: buffer_append(&c->output, data, data_len);
1.25 markus 2033: xfree(data);
1.1 deraadt 2034: }
1.121 markus 2035:
1.249 djm 2036: /* ARGSUSED */
1.49 markus 2037: void
1.154 markus 2038: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2039: {
2040: int id;
2041: char *data;
1.177 markus 2042: u_int data_len, tcode;
1.44 markus 2043: Channel *c;
2044:
2045: /* Get the channel number and verify it. */
2046: id = packet_get_int();
2047: c = channel_lookup(id);
2048:
2049: if (c == NULL)
2050: packet_disconnect("Received extended_data for bad channel %d.", id);
2051: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2052: logit("channel %d: ext data for non open", id);
1.44 markus 2053: return;
1.172 markus 2054: }
2055: if (c->flags & CHAN_EOF_RCVD) {
2056: if (datafellows & SSH_BUG_EXTEOF)
2057: debug("channel %d: accepting ext data after eof", id);
2058: else
2059: packet_disconnect("Received extended_data after EOF "
2060: "on channel %d.", id);
1.44 markus 2061: }
2062: tcode = packet_get_int();
2063: if (c->efd == -1 ||
2064: c->extended_usage != CHAN_EXTENDED_WRITE ||
2065: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2066: logit("channel %d: bad ext data", c->self);
1.44 markus 2067: return;
2068: }
2069: data = packet_get_string(&data_len);
1.152 markus 2070: packet_check_eom();
1.44 markus 2071: if (data_len > c->local_window) {
1.188 itojun 2072: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2073: c->self, data_len, c->local_window);
2074: xfree(data);
2075: return;
2076: }
1.70 markus 2077: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2078: c->local_window -= data_len;
2079: buffer_append(&c->extended, data, data_len);
2080: xfree(data);
2081: }
2082:
1.249 djm 2083: /* ARGSUSED */
1.49 markus 2084: void
1.154 markus 2085: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2086: {
2087: int id;
2088: Channel *c;
2089:
2090: id = packet_get_int();
1.152 markus 2091: packet_check_eom();
1.41 markus 2092: c = channel_lookup(id);
2093: if (c == NULL)
2094: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2095: chan_rcvd_ieof(c);
1.133 markus 2096:
2097: /* XXX force input close */
1.156 markus 2098: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2099: debug("channel %d: FORCE input drain", c->self);
2100: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2101: if (buffer_len(&c->input) == 0)
2102: chan_ibuf_empty(c);
1.133 markus 2103: }
2104:
1.41 markus 2105: }
1.1 deraadt 2106:
1.249 djm 2107: /* ARGSUSED */
1.49 markus 2108: void
1.154 markus 2109: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2110: {
1.41 markus 2111: int id;
2112: Channel *c;
1.1 deraadt 2113:
1.41 markus 2114: id = packet_get_int();
1.152 markus 2115: packet_check_eom();
1.41 markus 2116: c = channel_lookup(id);
2117: if (c == NULL)
2118: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2119:
2120: /*
2121: * Send a confirmation that we have closed the channel and no more
2122: * data is coming for it.
2123: */
1.25 markus 2124: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2125: packet_put_int(c->remote_id);
1.25 markus 2126: packet_send();
2127:
1.27 markus 2128: /*
2129: * If the channel is in closed state, we have sent a close request,
2130: * and the other side will eventually respond with a confirmation.
2131: * Thus, we cannot free the channel here, because then there would be
2132: * no-one to receive the confirmation. The channel gets freed when
2133: * the confirmation arrives.
2134: */
1.41 markus 2135: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2136: /*
2137: * Not a closed channel - mark it as draining, which will
2138: * cause it to be freed later.
2139: */
1.158 markus 2140: buffer_clear(&c->input);
1.41 markus 2141: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2142: }
1.1 deraadt 2143: }
2144:
1.41 markus 2145: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2146: /* ARGSUSED */
1.49 markus 2147: void
1.154 markus 2148: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2149: {
2150: int id = packet_get_int();
2151: Channel *c = channel_lookup(id);
1.151 markus 2152:
1.152 markus 2153: packet_check_eom();
1.41 markus 2154: if (c == NULL)
2155: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2156: chan_rcvd_oclose(c);
2157: }
1.1 deraadt 2158:
1.249 djm 2159: /* ARGSUSED */
1.49 markus 2160: void
1.154 markus 2161: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2162: {
1.41 markus 2163: int id = packet_get_int();
2164: Channel *c = channel_lookup(id);
1.1 deraadt 2165:
1.152 markus 2166: packet_check_eom();
1.41 markus 2167: if (c == NULL)
2168: packet_disconnect("Received close confirmation for "
2169: "out-of-range channel %d.", id);
2170: if (c->type != SSH_CHANNEL_CLOSED)
2171: packet_disconnect("Received close confirmation for "
2172: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2173: channel_free(c);
1.1 deraadt 2174: }
2175:
1.249 djm 2176: /* ARGSUSED */
1.49 markus 2177: void
1.154 markus 2178: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2179: {
1.41 markus 2180: int id, remote_id;
2181: Channel *c;
1.1 deraadt 2182:
1.41 markus 2183: id = packet_get_int();
2184: c = channel_lookup(id);
1.25 markus 2185:
1.41 markus 2186: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2187: packet_disconnect("Received open confirmation for "
2188: "non-opening channel %d.", id);
2189: remote_id = packet_get_int();
1.27 markus 2190: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2191: c->remote_id = remote_id;
2192: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2193:
2194: if (compat20) {
2195: c->remote_window = packet_get_int();
2196: c->remote_maxpacket = packet_get_int();
1.165 markus 2197: if (c->confirm) {
1.70 markus 2198: debug2("callback start");
1.204 djm 2199: c->confirm(c->self, c->confirm_ctx);
1.70 markus 2200: debug2("callback done");
1.44 markus 2201: }
1.194 markus 2202: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2203: c->remote_window, c->remote_maxpacket);
2204: }
1.152 markus 2205: packet_check_eom();
1.1 deraadt 2206: }
2207:
1.127 itojun 2208: static char *
1.114 markus 2209: reason2txt(int reason)
2210: {
1.143 deraadt 2211: switch (reason) {
1.114 markus 2212: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2213: return "administratively prohibited";
2214: case SSH2_OPEN_CONNECT_FAILED:
2215: return "connect failed";
2216: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2217: return "unknown channel type";
2218: case SSH2_OPEN_RESOURCE_SHORTAGE:
2219: return "resource shortage";
2220: }
1.117 stevesk 2221: return "unknown reason";
1.114 markus 2222: }
2223:
1.249 djm 2224: /* ARGSUSED */
1.49 markus 2225: void
1.154 markus 2226: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2227: {
1.86 markus 2228: int id, reason;
2229: char *msg = NULL, *lang = NULL;
1.41 markus 2230: Channel *c;
2231:
2232: id = packet_get_int();
2233: c = channel_lookup(id);
1.25 markus 2234:
1.41 markus 2235: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2236: packet_disconnect("Received open failure for "
2237: "non-opening channel %d.", id);
1.44 markus 2238: if (compat20) {
1.86 markus 2239: reason = packet_get_int();
1.110 markus 2240: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2241: msg = packet_get_string(NULL);
2242: lang = packet_get_string(NULL);
2243: }
1.188 itojun 2244: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2245: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 2246: if (msg != NULL)
2247: xfree(msg);
2248: if (lang != NULL)
2249: xfree(lang);
1.44 markus 2250: }
1.152 markus 2251: packet_check_eom();
1.25 markus 2252: /* Free the channel. This will also close the socket. */
1.113 markus 2253: channel_free(c);
1.44 markus 2254: }
2255:
1.249 djm 2256: /* ARGSUSED */
1.121 markus 2257: void
1.154 markus 2258: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2259: {
2260: Channel *c;
1.178 markus 2261: int id;
2262: u_int adjust;
1.121 markus 2263:
2264: if (!compat20)
2265: return;
2266:
2267: /* Get the channel number and verify it. */
2268: id = packet_get_int();
2269: c = channel_lookup(id);
1.1 deraadt 2270:
1.229 markus 2271: if (c == NULL) {
2272: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2273: return;
2274: }
2275: adjust = packet_get_int();
1.152 markus 2276: packet_check_eom();
1.178 markus 2277: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2278: c->remote_window += adjust;
2279: }
1.1 deraadt 2280:
1.249 djm 2281: /* ARGSUSED */
1.121 markus 2282: void
1.154 markus 2283: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2284: {
1.121 markus 2285: Channel *c = NULL;
2286: u_short host_port;
2287: char *host, *originator_string;
2288: int remote_id, sock = -1;
2289:
2290: remote_id = packet_get_int();
2291: host = packet_get_string(NULL);
2292: host_port = packet_get_int();
1.25 markus 2293:
1.121 markus 2294: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2295: originator_string = packet_get_string(NULL);
2296: } else {
2297: originator_string = xstrdup("unknown (remote did not supply name)");
2298: }
1.152 markus 2299: packet_check_eom();
1.121 markus 2300: sock = channel_connect_to(host, host_port);
2301: if (sock != -1) {
2302: c = channel_new("connected socket",
2303: SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
2304: originator_string, 1);
1.167 markus 2305: c->remote_id = remote_id;
1.25 markus 2306: }
1.190 markus 2307: xfree(originator_string);
1.121 markus 2308: if (c == NULL) {
2309: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2310: packet_put_int(remote_id);
2311: packet_send();
2312: }
2313: xfree(host);
1.1 deraadt 2314: }
2315:
1.121 markus 2316:
2317: /* -- tcp forwarding */
1.135 markus 2318:
2319: void
2320: channel_set_af(int af)
2321: {
2322: IPv4or6 = af;
2323: }
1.121 markus 2324:
1.160 markus 2325: static int
2326: channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port,
2327: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2328: {
1.113 markus 2329: Channel *c;
1.226 djm 2330: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2331: struct addrinfo hints, *ai, *aitop;
1.212 djm 2332: const char *host, *addr;
1.35 markus 2333: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.25 markus 2334:
1.160 markus 2335: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2336: listen_addr : host_to_connect;
1.212 djm 2337: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2338:
1.160 markus 2339: if (host == NULL) {
2340: error("No forward host name.");
1.218 markus 2341: return 0;
1.73 markus 2342: }
1.113 markus 2343: if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
1.87 markus 2344: error("Forward host name too long.");
1.218 markus 2345: return 0;
1.87 markus 2346: }
1.25 markus 2347:
1.28 markus 2348: /*
1.212 djm 2349: * Determine whether or not a port forward listens to loopback,
1.213 deraadt 2350: * specified address or wildcard. On the client, a specified bind
2351: * address will always override gateway_ports. On the server, a
2352: * gateway_ports of 1 (``yes'') will override the client's
2353: * specification and force a wildcard bind, whereas a value of 2
2354: * (``clientspecified'') will bind to whatever address the client
1.212 djm 2355: * asked for.
2356: *
2357: * Special-case listen_addrs are:
2358: *
2359: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2360: * "" (empty string), "*" -> wildcard v4/v6
2361: * "localhost" -> loopback v4/v6
2362: */
2363: addr = NULL;
2364: if (listen_addr == NULL) {
2365: /* No address specified: default to gateway_ports setting */
2366: if (gateway_ports)
2367: wildcard = 1;
2368: } else if (gateway_ports || is_client) {
2369: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2370: strcmp(listen_addr, "0.0.0.0") == 0) ||
2371: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2372: (!is_client && gateway_ports == 1))
2373: wildcard = 1;
2374: else if (strcmp(listen_addr, "localhost") != 0)
2375: addr = listen_addr;
2376: }
2377:
2378: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2379: type, wildcard, (addr == NULL) ? "NULL" : addr);
2380:
2381: /*
1.35 markus 2382: * getaddrinfo returns a loopback address if the hostname is
2383: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2384: */
1.35 markus 2385: memset(&hints, 0, sizeof(hints));
2386: hints.ai_family = IPv4or6;
1.212 djm 2387: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2388: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2389: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2390: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2391: if (addr == NULL) {
2392: /* This really shouldn't happen */
2393: packet_disconnect("getaddrinfo: fatal error: %s",
2394: gai_strerror(r));
2395: } else {
1.218 markus 2396: error("channel_setup_fwd_listener: "
1.212 djm 2397: "getaddrinfo(%.64s): %s", addr, gai_strerror(r));
2398: }
1.218 markus 2399: return 0;
1.212 djm 2400: }
1.35 markus 2401:
2402: for (ai = aitop; ai; ai = ai->ai_next) {
2403: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2404: continue;
2405: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2406: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2407: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2408: continue;
2409: }
2410: /* Create a port to listen for the host. */
1.189 markus 2411: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2412: if (sock < 0) {
2413: /* this is no error since kernel may not support ipv6 */
2414: verbose("socket: %.100s", strerror(errno));
2415: continue;
2416: }
1.226 djm 2417:
2418: channel_set_reuseaddr(sock);
1.182 stevesk 2419:
1.35 markus 2420: debug("Local forwarding listening on %s port %s.", ntop, strport);
2421:
2422: /* Bind the socket to the address. */
2423: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2424: /* address can be in use ipv6 address is already bound */
2425: verbose("bind: %.100s", strerror(errno));
2426: close(sock);
2427: continue;
2428: }
2429: /* Start listening for connections on the socket. */
1.199 markus 2430: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2431: error("listen: %.100s", strerror(errno));
2432: close(sock);
2433: continue;
2434: }
2435: /* Allocate a channel number for the socket. */
1.121 markus 2436: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2437: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2438: 0, "port listener", 1);
1.113 markus 2439: strlcpy(c->path, host, sizeof(c->path));
2440: c->host_port = port_to_connect;
2441: c->listening_port = listen_port;
1.35 markus 2442: success = 1;
2443: }
2444: if (success == 0)
1.160 markus 2445: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2446: listen_port);
1.35 markus 2447: freeaddrinfo(aitop);
1.87 markus 2448: return success;
1.25 markus 2449: }
1.1 deraadt 2450:
1.202 djm 2451: int
2452: channel_cancel_rport_listener(const char *host, u_short port)
2453: {
1.209 avsm 2454: u_int i;
2455: int found = 0;
1.202 djm 2456:
1.213 deraadt 2457: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2458: Channel *c = channels[i];
2459:
2460: if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
2461: strncmp(c->path, host, sizeof(c->path)) == 0 &&
1.208 deraadt 2462: c->listening_port == port) {
1.210 djm 2463: debug2("%s: close channel %d", __func__, i);
1.202 djm 2464: channel_free(c);
2465: found = 1;
2466: }
2467: }
2468:
2469: return (found);
2470: }
2471:
1.160 markus 2472: /* protocol local port fwd, used by ssh (and sshd in v1) */
2473: int
1.212 djm 2474: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2475: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2476: {
2477: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.212 djm 2478: listen_host, listen_port, host_to_connect, port_to_connect,
2479: gateway_ports);
1.160 markus 2480: }
2481:
2482: /* protocol v2 remote port fwd, used by sshd */
2483: int
2484: channel_setup_remote_fwd_listener(const char *listen_address,
2485: u_short listen_port, int gateway_ports)
2486: {
2487: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
2488: listen_address, listen_port, NULL, 0, gateway_ports);
2489: }
2490:
1.27 markus 2491: /*
2492: * Initiate forwarding of connections to port "port" on remote host through
2493: * the secure channel to host:port from local side.
2494: */
1.1 deraadt 2495:
1.253 markus 2496: int
1.212 djm 2497: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2498: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2499: {
1.153 markus 2500: int type, success = 0;
1.73 markus 2501:
1.25 markus 2502: /* Record locally that connection to this host/port is permitted. */
2503: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2504: fatal("channel_request_remote_forwarding: too many forwards");
2505:
2506: /* Send the forward request to the remote side. */
1.44 markus 2507: if (compat20) {
1.212 djm 2508: const char *address_to_bind;
2509: if (listen_host == NULL)
2510: address_to_bind = "localhost";
2511: else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0)
2512: address_to_bind = "";
2513: else
2514: address_to_bind = listen_host;
2515:
1.44 markus 2516: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2517: packet_put_cstring("tcpip-forward");
1.173 markus 2518: packet_put_char(1); /* boolean: want reply */
1.44 markus 2519: packet_put_cstring(address_to_bind);
2520: packet_put_int(listen_port);
1.73 markus 2521: packet_send();
2522: packet_write_wait();
2523: /* Assume that server accepts the request */
2524: success = 1;
1.44 markus 2525: } else {
2526: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2527: packet_put_int(listen_port);
2528: packet_put_cstring(host_to_connect);
1.44 markus 2529: packet_put_int(port_to_connect);
2530: packet_send();
2531: packet_write_wait();
1.73 markus 2532:
2533: /* Wait for response from the remote side. */
1.153 markus 2534: type = packet_read();
1.73 markus 2535: switch (type) {
2536: case SSH_SMSG_SUCCESS:
2537: success = 1;
2538: break;
2539: case SSH_SMSG_FAILURE:
2540: break;
2541: default:
2542: /* Unknown packet */
2543: packet_disconnect("Protocol error for port forward request:"
2544: "received packet type %d.", type);
2545: }
2546: }
2547: if (success) {
2548: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2549: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2550: permitted_opens[num_permitted_opens].listen_port = listen_port;
2551: num_permitted_opens++;
1.44 markus 2552: }
1.253 markus 2553: return (success ? 0 : -1);
1.1 deraadt 2554: }
2555:
1.27 markus 2556: /*
1.208 deraadt 2557: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 2558: * local side.
2559: */
2560: void
1.212 djm 2561: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 2562: {
2563: int i;
2564:
2565: if (!compat20)
2566: return;
2567:
2568: for (i = 0; i < num_permitted_opens; i++) {
1.208 deraadt 2569: if (permitted_opens[i].host_to_connect != NULL &&
1.202 djm 2570: permitted_opens[i].listen_port == port)
2571: break;
2572: }
2573: if (i >= num_permitted_opens) {
2574: debug("%s: requested forward not found", __func__);
2575: return;
2576: }
2577: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2578: packet_put_cstring("cancel-tcpip-forward");
2579: packet_put_char(0);
1.212 djm 2580: packet_put_cstring(host == NULL ? "" : host);
1.202 djm 2581: packet_put_int(port);
2582: packet_send();
2583:
2584: permitted_opens[i].listen_port = 0;
2585: permitted_opens[i].port_to_connect = 0;
1.227 stevesk 2586: xfree(permitted_opens[i].host_to_connect);
1.202 djm 2587: permitted_opens[i].host_to_connect = NULL;
2588: }
2589:
2590: /*
1.27 markus 2591: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2592: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 2593: * message if there was an error).
1.27 markus 2594: */
1.253 markus 2595: int
1.56 markus 2596: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2597: {
1.31 markus 2598: u_short port, host_port;
1.253 markus 2599: int success = 0;
1.25 markus 2600: char *hostname;
1.1 deraadt 2601:
1.25 markus 2602: /* Get arguments from the packet. */
2603: port = packet_get_int();
2604: hostname = packet_get_string(NULL);
2605: host_port = packet_get_int();
2606:
1.27 markus 2607: /*
2608: * Check that an unprivileged user is not trying to forward a
2609: * privileged port.
2610: */
1.25 markus 2611: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 2612: packet_disconnect(
2613: "Requested forwarding of port %d but user is not root.",
2614: port);
2615: if (host_port == 0)
2616: packet_disconnect("Dynamic forwarding denied.");
2617:
1.73 markus 2618: /* Initiate forwarding */
1.253 markus 2619: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 2620: host_port, gateway_ports);
1.25 markus 2621:
2622: /* Free the argument string. */
2623: xfree(hostname);
1.253 markus 2624:
2625: return (success ? 0 : -1);
1.1 deraadt 2626: }
2627:
1.99 markus 2628: /*
2629: * Permits opening to any host/port if permitted_opens[] is empty. This is
2630: * usually called by the server, because the user could connect to any port
2631: * anyway, and the server has no way to know but to trust the client anyway.
2632: */
2633: void
1.142 itojun 2634: channel_permit_all_opens(void)
1.99 markus 2635: {
2636: if (num_permitted_opens == 0)
2637: all_opens_permitted = 1;
2638: }
2639:
1.101 markus 2640: void
1.99 markus 2641: channel_add_permitted_opens(char *host, int port)
2642: {
2643: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1.253 markus 2644: fatal("channel_add_permitted_opens: too many forwards");
1.99 markus 2645: debug("allow port forwarding to host %s port %d", host, port);
2646:
2647: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2648: permitted_opens[num_permitted_opens].port_to_connect = port;
2649: num_permitted_opens++;
2650:
2651: all_opens_permitted = 0;
2652: }
2653:
1.258 dtucker 2654: int
1.257 dtucker 2655: channel_add_adm_permitted_opens(char *host, int port)
2656: {
2657: if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2658: fatal("channel_add_adm_permitted_opens: too many forwards");
1.258 dtucker 2659: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 2660:
2661: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
2662: = xstrdup(host);
2663: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.258 dtucker 2664: return ++num_adm_permitted_opens;
1.257 dtucker 2665: }
2666:
2667: void
1.99 markus 2668: channel_clear_permitted_opens(void)
2669: {
2670: int i;
2671:
2672: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2673: if (permitted_opens[i].host_to_connect != NULL)
2674: xfree(permitted_opens[i].host_to_connect);
1.99 markus 2675: num_permitted_opens = 0;
1.257 dtucker 2676: }
2677:
2678: void
2679: channel_clear_adm_permitted_opens(void)
2680: {
2681: int i;
1.99 markus 2682:
1.257 dtucker 2683: for (i = 0; i < num_adm_permitted_opens; i++)
2684: if (permitted_adm_opens[i].host_to_connect != NULL)
2685: xfree(permitted_adm_opens[i].host_to_connect);
2686: num_adm_permitted_opens = 0;
1.99 markus 2687: }
2688:
2689: /* return socket to remote host, port */
1.127 itojun 2690: static int
1.99 markus 2691: connect_to(const char *host, u_short port)
1.41 markus 2692: {
2693: struct addrinfo hints, *ai, *aitop;
2694: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2695: int gaierr;
2696: int sock = -1;
2697:
2698: memset(&hints, 0, sizeof(hints));
2699: hints.ai_family = IPv4or6;
2700: hints.ai_socktype = SOCK_STREAM;
1.99 markus 2701: snprintf(strport, sizeof strport, "%d", port);
1.41 markus 2702: if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1.99 markus 2703: error("connect_to %.100s: unknown host (%s)", host,
2704: gai_strerror(gaierr));
1.41 markus 2705: return -1;
2706: }
2707: for (ai = aitop; ai; ai = ai->ai_next) {
2708: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2709: continue;
2710: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2711: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.99 markus 2712: error("connect_to: getnameinfo failed");
1.41 markus 2713: continue;
2714: }
1.189 markus 2715: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.41 markus 2716: if (sock < 0) {
1.186 djm 2717: if (ai->ai_next == NULL)
2718: error("socket: %.100s", strerror(errno));
2719: else
2720: verbose("socket: %.100s", strerror(errno));
1.41 markus 2721: continue;
2722: }
1.205 djm 2723: if (set_nonblock(sock) == -1)
2724: fatal("%s: set_nonblock(%d)", __func__, sock);
1.75 markus 2725: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
2726: errno != EINPROGRESS) {
1.99 markus 2727: error("connect_to %.100s port %s: %.100s", ntop, strport,
1.41 markus 2728: strerror(errno));
2729: close(sock);
1.89 stevesk 2730: continue; /* fail -- try next */
1.41 markus 2731: }
2732: break; /* success */
2733:
2734: }
2735: freeaddrinfo(aitop);
2736: if (!ai) {
1.99 markus 2737: error("connect_to %.100s port %d: failed.", host, port);
1.41 markus 2738: return -1;
2739: }
2740: /* success */
1.169 stevesk 2741: set_nodelay(sock);
1.41 markus 2742: return sock;
2743: }
1.99 markus 2744:
1.73 markus 2745: int
1.130 stevesk 2746: channel_connect_by_listen_address(u_short listen_port)
1.73 markus 2747: {
2748: int i;
1.99 markus 2749:
1.73 markus 2750: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2751: if (permitted_opens[i].host_to_connect != NULL &&
2752: permitted_opens[i].listen_port == listen_port)
1.99 markus 2753: return connect_to(
1.73 markus 2754: permitted_opens[i].host_to_connect,
2755: permitted_opens[i].port_to_connect);
1.74 markus 2756: error("WARNING: Server requests forwarding for unknown listen_port %d",
2757: listen_port);
1.73 markus 2758: return -1;
2759: }
2760:
1.99 markus 2761: /* Check if connecting to that port is permitted and connect. */
2762: int
2763: channel_connect_to(const char *host, u_short port)
2764: {
1.257 dtucker 2765: int i, permit, permit_adm = 1;
1.99 markus 2766:
2767: permit = all_opens_permitted;
2768: if (!permit) {
2769: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2770: if (permitted_opens[i].host_to_connect != NULL &&
2771: permitted_opens[i].port_to_connect == port &&
1.99 markus 2772: strcmp(permitted_opens[i].host_to_connect, host) == 0)
2773: permit = 1;
1.257 dtucker 2774: }
1.99 markus 2775:
1.257 dtucker 2776: if (num_adm_permitted_opens > 0) {
2777: permit_adm = 0;
2778: for (i = 0; i < num_adm_permitted_opens; i++)
2779: if (permitted_adm_opens[i].host_to_connect != NULL &&
2780: permitted_adm_opens[i].port_to_connect == port &&
2781: strcmp(permitted_adm_opens[i].host_to_connect, host)
2782: == 0)
2783: permit_adm = 1;
1.99 markus 2784: }
1.257 dtucker 2785:
2786: if (!permit || !permit_adm) {
1.188 itojun 2787: logit("Received request to connect to host %.100s port %d, "
1.99 markus 2788: "but the request was denied.", host, port);
2789: return -1;
2790: }
2791: return connect_to(host, port);
1.204 djm 2792: }
2793:
2794: void
2795: channel_send_window_changes(void)
2796: {
1.209 avsm 2797: u_int i;
1.204 djm 2798: struct winsize ws;
2799:
2800: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 2801: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 2802: channels[i]->type != SSH_CHANNEL_OPEN)
2803: continue;
2804: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
2805: continue;
2806: channel_request_start(i, "window-change", 0);
1.238 deraadt 2807: packet_put_int((u_int)ws.ws_col);
2808: packet_put_int((u_int)ws.ws_row);
2809: packet_put_int((u_int)ws.ws_xpixel);
2810: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 2811: packet_send();
2812: }
1.99 markus 2813: }
2814:
1.121 markus 2815: /* -- X11 forwarding */
1.1 deraadt 2816:
1.27 markus 2817: /*
2818: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 2819: * Returns 0 and a suitable display number for the DISPLAY variable
2820: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 2821: */
1.141 stevesk 2822: int
1.163 stevesk 2823: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 2824: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 2825: {
1.149 markus 2826: Channel *nc = NULL;
1.31 markus 2827: int display_number, sock;
2828: u_short port;
1.35 markus 2829: struct addrinfo hints, *ai, *aitop;
2830: char strport[NI_MAXSERV];
2831: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 2832:
1.224 markus 2833: if (chanids == NULL)
2834: return -1;
2835:
1.33 markus 2836: for (display_number = x11_display_offset;
1.148 deraadt 2837: display_number < MAX_DISPLAYS;
2838: display_number++) {
1.25 markus 2839: port = 6000 + display_number;
1.35 markus 2840: memset(&hints, 0, sizeof(hints));
2841: hints.ai_family = IPv4or6;
1.163 stevesk 2842: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 2843: hints.ai_socktype = SOCK_STREAM;
2844: snprintf(strport, sizeof strport, "%d", port);
2845: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
2846: error("getaddrinfo: %.100s", gai_strerror(gaierr));
1.141 stevesk 2847: return -1;
1.25 markus 2848: }
1.35 markus 2849: for (ai = aitop; ai; ai = ai->ai_next) {
2850: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
2851: continue;
1.189 markus 2852: sock = socket(ai->ai_family, ai->ai_socktype,
2853: ai->ai_protocol);
1.35 markus 2854: if (sock < 0) {
2855: error("socket: %.100s", strerror(errno));
1.203 markus 2856: freeaddrinfo(aitop);
1.141 stevesk 2857: return -1;
1.35 markus 2858: }
1.226 djm 2859: channel_set_reuseaddr(sock);
1.35 markus 2860: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 2861: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 2862: close(sock);
1.183 itojun 2863:
2864: if (ai->ai_next)
2865: continue;
2866:
1.35 markus 2867: for (n = 0; n < num_socks; n++) {
2868: close(socks[n]);
2869: }
2870: num_socks = 0;
2871: break;
2872: }
2873: socks[num_socks++] = sock;
2874: if (num_socks == NUM_SOCKS)
2875: break;
1.25 markus 2876: }
1.83 stevesk 2877: freeaddrinfo(aitop);
1.35 markus 2878: if (num_socks > 0)
2879: break;
1.25 markus 2880: }
2881: if (display_number >= MAX_DISPLAYS) {
2882: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 2883: return -1;
1.25 markus 2884: }
2885: /* Start listening for connections on the socket. */
1.35 markus 2886: for (n = 0; n < num_socks; n++) {
2887: sock = socks[n];
1.199 markus 2888: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2889: error("listen: %.100s", strerror(errno));
2890: close(sock);
1.141 stevesk 2891: return -1;
1.35 markus 2892: }
1.25 markus 2893: }
1.35 markus 2894:
2895: /* Allocate a channel for each socket. */
1.242 djm 2896: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 2897: for (n = 0; n < num_socks; n++) {
2898: sock = socks[n];
1.149 markus 2899: nc = channel_new("x11 listener",
1.51 markus 2900: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2901: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 2902: 0, "X11 inet listener", 1);
1.167 markus 2903: nc->single_connection = single_connection;
1.224 markus 2904: (*chanids)[n] = nc->self;
1.35 markus 2905: }
1.224 markus 2906: (*chanids)[n] = -1;
1.1 deraadt 2907:
1.141 stevesk 2908: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 2909: *display_numberp = display_number;
2910: return (0);
1.1 deraadt 2911: }
2912:
1.127 itojun 2913: static int
1.77 markus 2914: connect_local_xsocket(u_int dnr)
1.1 deraadt 2915: {
1.25 markus 2916: int sock;
2917: struct sockaddr_un addr;
2918:
1.147 stevesk 2919: sock = socket(AF_UNIX, SOCK_STREAM, 0);
2920: if (sock < 0)
2921: error("socket: %.100s", strerror(errno));
2922: memset(&addr, 0, sizeof(addr));
2923: addr.sun_family = AF_UNIX;
2924: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 2925: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 2926: return sock;
2927: close(sock);
1.25 markus 2928: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2929: return -1;
1.1 deraadt 2930: }
2931:
1.51 markus 2932: int
2933: x11_connect_display(void)
1.1 deraadt 2934: {
1.248 deraadt 2935: u_int display_number;
1.25 markus 2936: const char *display;
1.51 markus 2937: char buf[1024], *cp;
1.35 markus 2938: struct addrinfo hints, *ai, *aitop;
2939: char strport[NI_MAXSERV];
1.248 deraadt 2940: int gaierr, sock = 0;
1.25 markus 2941:
2942: /* Try to open a socket for the local X server. */
2943: display = getenv("DISPLAY");
2944: if (!display) {
2945: error("DISPLAY not set.");
1.51 markus 2946: return -1;
1.25 markus 2947: }
1.27 markus 2948: /*
2949: * Now we decode the value of the DISPLAY variable and make a
2950: * connection to the real X server.
2951: */
2952:
2953: /*
2954: * Check if it is a unix domain socket. Unix domain displays are in
2955: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2956: */
1.25 markus 2957: if (strncmp(display, "unix:", 5) == 0 ||
2958: display[0] == ':') {
2959: /* Connect to the unix domain socket. */
1.248 deraadt 2960: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 2961: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2962: display);
1.51 markus 2963: return -1;
1.25 markus 2964: }
2965: /* Create a socket. */
2966: sock = connect_local_xsocket(display_number);
2967: if (sock < 0)
1.51 markus 2968: return -1;
1.25 markus 2969:
2970: /* OK, we now have a connection to the display. */
1.51 markus 2971: return sock;
1.25 markus 2972: }
1.27 markus 2973: /*
2974: * Connect to an inet socket. The DISPLAY value is supposedly
2975: * hostname:d[.s], where hostname may also be numeric IP address.
2976: */
1.145 stevesk 2977: strlcpy(buf, display, sizeof(buf));
1.25 markus 2978: cp = strchr(buf, ':');
2979: if (!cp) {
2980: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 2981: return -1;
1.25 markus 2982: }
2983: *cp = 0;
1.27 markus 2984: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 2985: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 2986: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 2987: display);
1.51 markus 2988: return -1;
1.25 markus 2989: }
1.35 markus 2990:
2991: /* Look up the host address */
2992: memset(&hints, 0, sizeof(hints));
2993: hints.ai_family = IPv4or6;
2994: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 2995: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 2996: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2997: error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
1.51 markus 2998: return -1;
1.25 markus 2999: }
1.35 markus 3000: for (ai = aitop; ai; ai = ai->ai_next) {
3001: /* Create a socket. */
1.189 markus 3002: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3003: if (sock < 0) {
1.194 markus 3004: debug2("socket: %.100s", strerror(errno));
1.41 markus 3005: continue;
3006: }
3007: /* Connect it to the display. */
3008: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 3009: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 3010: 6000 + display_number, strerror(errno));
3011: close(sock);
3012: continue;
3013: }
3014: /* Success */
3015: break;
1.35 markus 3016: }
3017: freeaddrinfo(aitop);
3018: if (!ai) {
1.248 deraadt 3019: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3020: strerror(errno));
1.51 markus 3021: return -1;
1.25 markus 3022: }
1.162 stevesk 3023: set_nodelay(sock);
1.51 markus 3024: return sock;
3025: }
3026:
3027: /*
3028: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3029: * the remote channel number. We should do whatever we want, and respond
3030: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3031: */
3032:
1.259 stevesk 3033: /* ARGSUSED */
1.51 markus 3034: void
1.154 markus 3035: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3036: {
1.113 markus 3037: Channel *c = NULL;
3038: int remote_id, sock = 0;
1.51 markus 3039: char *remote_host;
1.25 markus 3040:
1.113 markus 3041: debug("Received X11 open request.");
1.51 markus 3042:
1.113 markus 3043: remote_id = packet_get_int();
1.121 markus 3044:
3045: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3046: remote_host = packet_get_string(NULL);
1.51 markus 3047: } else {
3048: remote_host = xstrdup("unknown (remote did not supply name)");
3049: }
1.152 markus 3050: packet_check_eom();
1.25 markus 3051:
1.51 markus 3052: /* Obtain a connection to the real X display. */
3053: sock = x11_connect_display();
1.113 markus 3054: if (sock != -1) {
3055: /* Allocate a channel for this connection. */
3056: c = channel_new("connected x11 socket",
3057: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3058: remote_host, 1);
1.167 markus 3059: c->remote_id = remote_id;
3060: c->force_drain = 1;
1.113 markus 3061: }
1.190 markus 3062: xfree(remote_host);
1.113 markus 3063: if (c == NULL) {
1.51 markus 3064: /* Send refusal to the remote host. */
3065: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3066: packet_put_int(remote_id);
1.51 markus 3067: } else {
3068: /* Send a confirmation to the remote host. */
3069: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3070: packet_put_int(remote_id);
3071: packet_put_int(c->self);
1.51 markus 3072: }
1.113 markus 3073: packet_send();
1.72 markus 3074: }
3075:
3076: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 3077: /* ARGSUSED */
1.72 markus 3078: void
1.154 markus 3079: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3080: {
3081: int rchan = packet_get_int();
1.180 deraadt 3082:
1.143 deraadt 3083: switch (type) {
1.72 markus 3084: case SSH_SMSG_AGENT_OPEN:
3085: error("Warning: ssh server tried agent forwarding.");
3086: break;
3087: case SSH_SMSG_X11_OPEN:
3088: error("Warning: ssh server tried X11 forwarding.");
3089: break;
3090: default:
1.154 markus 3091: error("deny_input_open: type %d", type);
1.72 markus 3092: break;
3093: }
1.230 stevesk 3094: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3095: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3096: packet_put_int(rchan);
3097: packet_send();
1.1 deraadt 3098: }
3099:
1.27 markus 3100: /*
3101: * Requests forwarding of X11 connections, generates fake authentication
3102: * data, and enables authentication spoofing.
1.121 markus 3103: * This should be called in the client only.
1.27 markus 3104: */
1.49 markus 3105: void
1.215 djm 3106: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.51 markus 3107: const char *proto, const char *data)
1.1 deraadt 3108: {
1.77 markus 3109: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3110: u_int i, value;
1.25 markus 3111: char *new_data;
3112: int screen_number;
3113: const char *cp;
1.207 avsm 3114: u_int32_t rnd = 0;
1.25 markus 3115:
1.220 markus 3116: if (x11_saved_display == NULL)
3117: x11_saved_display = xstrdup(disp);
3118: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3119: error("x11_request_forwarding_with_spoofing: different "
3120: "$DISPLAY already forwarded");
3121: return;
3122: }
3123:
1.215 djm 3124: cp = disp;
3125: if (disp)
3126: cp = strchr(disp, ':');
1.25 markus 3127: if (cp)
3128: cp = strchr(cp, '.');
3129: if (cp)
1.245 deraadt 3130: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3131: else
3132: screen_number = 0;
3133:
1.219 djm 3134: if (x11_saved_proto == NULL) {
3135: /* Save protocol name. */
3136: x11_saved_proto = xstrdup(proto);
3137: /*
1.221 djm 3138: * Extract real authentication data and generate fake data
1.219 djm 3139: * of the same length.
3140: */
3141: x11_saved_data = xmalloc(data_len);
3142: x11_fake_data = xmalloc(data_len);
3143: for (i = 0; i < data_len; i++) {
3144: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3145: fatal("x11_request_forwarding: bad "
3146: "authentication data: %.100s", data);
3147: if (i % 4 == 0)
3148: rnd = arc4random();
3149: x11_saved_data[i] = value;
3150: x11_fake_data[i] = rnd & 0xff;
3151: rnd >>= 8;
3152: }
3153: x11_saved_data_len = data_len;
3154: x11_fake_data_len = data_len;
1.25 markus 3155: }
3156:
3157: /* Convert the fake data into hex. */
1.219 djm 3158: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3159:
3160: /* Send the request packet. */
1.51 markus 3161: if (compat20) {
3162: channel_request_start(client_session_id, "x11-req", 0);
3163: packet_put_char(0); /* XXX bool single connection */
3164: } else {
3165: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3166: }
3167: packet_put_cstring(proto);
3168: packet_put_cstring(new_data);
1.25 markus 3169: packet_put_int(screen_number);
3170: packet_send();
3171: packet_write_wait();
3172: xfree(new_data);
1.1 deraadt 3173: }
3174:
1.121 markus 3175:
3176: /* -- agent forwarding */
3177:
1.1 deraadt 3178: /* Sends a message to the server to request authentication fd forwarding. */
3179:
1.49 markus 3180: void
1.142 itojun 3181: auth_request_forwarding(void)
1.1 deraadt 3182: {
1.25 markus 3183: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3184: packet_send();
3185: packet_write_wait();
1.1 deraadt 3186: }
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