Annotation of src/usr.bin/ssh/channels.c, Revision 1.301
1.301 ! dtucker 1: /* $OpenBSD: channels.c,v 1.300 2010/01/09 23:04:13 dtucker 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:
1.265 deraadt 42: #include <sys/types.h>
1.234 stevesk 43: #include <sys/ioctl.h>
1.235 stevesk 44: #include <sys/un.h>
1.251 stevesk 45: #include <sys/socket.h>
1.261 stevesk 46: #include <sys/time.h>
1.275 djm 47: #include <sys/queue.h>
1.251 stevesk 48:
49: #include <netinet/in.h>
50: #include <arpa/inet.h>
1.233 stevesk 51:
1.254 stevesk 52: #include <errno.h>
1.298 dtucker 53: #include <fcntl.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>
1.265 deraadt 60: #include <stdarg.h>
1.1 deraadt 61:
1.265 deraadt 62: #include "xmalloc.h"
1.1 deraadt 63: #include "ssh.h"
1.82 markus 64: #include "ssh1.h"
65: #include "ssh2.h"
1.1 deraadt 66: #include "packet.h"
1.82 markus 67: #include "log.h"
68: #include "misc.h"
1.265 deraadt 69: #include "buffer.h"
1.14 markus 70: #include "channels.h"
71: #include "compat.h"
1.82 markus 72: #include "canohost.h"
1.64 markus 73: #include "key.h"
74: #include "authfd.h"
1.147 stevesk 75: #include "pathnames.h"
1.1 deraadt 76:
1.121 markus 77: /* -- channel core */
1.12 markus 78:
1.27 markus 79: /*
80: * Pointer to an array containing all allocated channels. The array is
81: * dynamically extended as needed.
82: */
1.113 markus 83: static Channel **channels = NULL;
1.1 deraadt 84:
1.27 markus 85: /*
86: * Size of the channel array. All slots of the array must always be
1.113 markus 87: * initialized (at least the type field); unused slots set to NULL
1.27 markus 88: */
1.209 avsm 89: static u_int channels_alloc = 0;
1.1 deraadt 90:
1.27 markus 91: /*
92: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 93: * updated in channel_new.
1.27 markus 94: */
1.84 markus 95: static int channel_max_fd = 0;
1.1 deraadt 96:
97:
1.121 markus 98: /* -- tcp forwarding */
1.1 deraadt 99:
1.27 markus 100: /*
101: * Data structure for storing which hosts are permitted for forward requests.
102: * The local sides of any remote forwards are stored in this array to prevent
103: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
104: * network (which might be behind a firewall).
105: */
1.25 markus 106: typedef struct {
1.41 markus 107: char *host_to_connect; /* Connect to 'host'. */
108: u_short port_to_connect; /* Connect to 'port'. */
109: u_short listen_port; /* Remote side should listen port number. */
1.1 deraadt 110: } ForwardPermission;
111:
1.257 dtucker 112: /* List of all permitted host/port pairs to connect by the user. */
1.1 deraadt 113: static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
1.121 markus 114:
1.257 dtucker 115: /* List of all permitted host/port pairs to connect by the admin. */
116: static ForwardPermission permitted_adm_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
117:
118: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 119: static int num_permitted_opens = 0;
1.257 dtucker 120:
121: /* Number of permitted host/port pair in the array permitted by the admin. */
122: static int num_adm_permitted_opens = 0;
123:
1.27 markus 124: /*
125: * If this is true, all opens are permitted. This is the case on the server
126: * on which we have to trust the client anyway, and the user could do
127: * anything after logging in anyway.
128: */
1.1 deraadt 129: static int all_opens_permitted = 0;
130:
1.121 markus 131:
132: /* -- X11 forwarding */
133:
134: /* Maximum number of fake X11 displays to try. */
135: #define MAX_DISPLAYS 1000
136:
1.219 djm 137: /* Saved X11 local (client) display. */
138: static char *x11_saved_display = NULL;
139:
1.121 markus 140: /* Saved X11 authentication protocol name. */
141: static char *x11_saved_proto = NULL;
142:
143: /* Saved X11 authentication data. This is the real data. */
144: static char *x11_saved_data = NULL;
145: static u_int x11_saved_data_len = 0;
146:
147: /*
148: * Fake X11 authentication data. This is what the server will be sending us;
149: * we should replace any occurrences of this by the real data.
150: */
1.240 deraadt 151: static u_char *x11_fake_data = NULL;
1.121 markus 152: static u_int x11_fake_data_len;
153:
154:
155: /* -- agent forwarding */
156:
157: #define NUM_SOCKS 10
158:
1.82 markus 159: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 160: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 161:
1.121 markus 162: /* helper */
1.127 itojun 163: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 164:
1.276 djm 165: /* non-blocking connect helpers */
166: static int connect_next(struct channel_connect *);
167: static void channel_connect_ctx_free(struct channel_connect *);
168:
1.121 markus 169: /* -- channel core */
1.41 markus 170:
171: Channel *
1.229 markus 172: channel_by_id(int id)
1.41 markus 173: {
174: Channel *c;
1.113 markus 175:
1.209 avsm 176: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 177: logit("channel_by_id: %d: bad id", id);
1.41 markus 178: return NULL;
179: }
1.113 markus 180: c = channels[id];
181: if (c == NULL) {
1.229 markus 182: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 183: return NULL;
184: }
185: return c;
1.55 markus 186: }
187:
1.27 markus 188: /*
1.229 markus 189: * Returns the channel if it is allowed to receive protocol messages.
190: * Private channels, like listening sockets, may not receive messages.
191: */
192: Channel *
193: channel_lookup(int id)
194: {
195: Channel *c;
196:
197: if ((c = channel_by_id(id)) == NULL)
198: return (NULL);
199:
1.237 deraadt 200: switch (c->type) {
1.229 markus 201: case SSH_CHANNEL_X11_OPEN:
202: case SSH_CHANNEL_LARVAL:
203: case SSH_CHANNEL_CONNECTING:
204: case SSH_CHANNEL_DYNAMIC:
205: case SSH_CHANNEL_OPENING:
206: case SSH_CHANNEL_OPEN:
207: case SSH_CHANNEL_INPUT_DRAINING:
208: case SSH_CHANNEL_OUTPUT_DRAINING:
209: return (c);
210: }
211: logit("Non-public channel %d, type %d.", id, c->type);
212: return (NULL);
213: }
214:
215: /*
1.55 markus 216: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 217: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 218: */
1.127 itojun 219: static void
1.71 markus 220: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 221: int extusage, int nonblock, int is_tty)
1.1 deraadt 222: {
1.25 markus 223: /* Update the maximum file descriptor value. */
1.84 markus 224: channel_max_fd = MAX(channel_max_fd, rfd);
225: channel_max_fd = MAX(channel_max_fd, wfd);
226: channel_max_fd = MAX(channel_max_fd, efd);
227:
1.298 dtucker 228: if (rfd != -1)
229: fcntl(rfd, F_SETFD, FD_CLOEXEC);
230: if (wfd != -1 && wfd != rfd)
231: fcntl(wfd, F_SETFD, FD_CLOEXEC);
232: if (efd != -1 && efd != rfd && efd != wfd)
233: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 234:
1.52 markus 235: c->rfd = rfd;
236: c->wfd = wfd;
237: c->sock = (rfd == wfd) ? rfd : -1;
1.204 djm 238: c->ctl_fd = -1; /* XXX: set elsewhere */
1.52 markus 239: c->efd = efd;
240: c->extended_usage = extusage;
1.71 markus 241:
1.282 dtucker 242: if ((c->isatty = is_tty) != 0)
1.194 markus 243: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 244:
1.71 markus 245: /* enable nonblocking mode */
246: if (nonblock) {
247: if (rfd != -1)
248: set_nonblock(rfd);
249: if (wfd != -1)
250: set_nonblock(wfd);
251: if (efd != -1)
252: set_nonblock(efd);
253: }
1.52 markus 254: }
255:
256: /*
257: * Allocate a new channel object and set its type and socket. This will cause
258: * remote_name to be freed.
259: */
1.113 markus 260: Channel *
1.52 markus 261: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 262: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 263: {
1.209 avsm 264: int found;
265: u_int i;
1.52 markus 266: Channel *c;
1.25 markus 267:
268: /* Do initial allocation if this is the first call. */
269: if (channels_alloc == 0) {
270: channels_alloc = 10;
1.242 djm 271: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 272: for (i = 0; i < channels_alloc; i++)
1.113 markus 273: channels[i] = NULL;
1.25 markus 274: }
275: /* Try to find a free slot where to put the new channel. */
276: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 277: if (channels[i] == NULL) {
1.25 markus 278: /* Found a free slot. */
1.209 avsm 279: found = (int)i;
1.25 markus 280: break;
281: }
1.209 avsm 282: if (found < 0) {
1.27 markus 283: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 284: found = channels_alloc;
1.179 markus 285: if (channels_alloc > 10000)
286: fatal("channel_new: internal error: channels_alloc %d "
287: "too big.", channels_alloc);
1.243 djm 288: channels = xrealloc(channels, channels_alloc + 10,
289: sizeof(Channel *));
1.195 markus 290: channels_alloc += 10;
1.70 markus 291: debug2("channel: expanding %d", channels_alloc);
1.25 markus 292: for (i = found; i < channels_alloc; i++)
1.113 markus 293: channels[i] = NULL;
1.25 markus 294: }
1.113 markus 295: /* Initialize and return new channel. */
1.242 djm 296: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 297: buffer_init(&c->input);
298: buffer_init(&c->output);
1.41 markus 299: buffer_init(&c->extended);
1.293 djm 300: c->path = NULL;
1.159 markus 301: c->ostate = CHAN_OUTPUT_OPEN;
302: c->istate = CHAN_INPUT_OPEN;
303: c->flags = 0;
1.281 djm 304: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 305: c->self = found;
306: c->type = type;
1.41 markus 307: c->ctype = ctype;
1.51 markus 308: c->local_window = window;
309: c->local_window_max = window;
310: c->local_consumed = 0;
311: c->local_maxpacket = maxpack;
1.25 markus 312: c->remote_id = -1;
1.190 markus 313: c->remote_name = xstrdup(remote_name);
1.41 markus 314: c->remote_window = 0;
315: c->remote_maxpacket = 0;
1.133 markus 316: c->force_drain = 0;
1.149 markus 317: c->single_connection = 0;
1.131 markus 318: c->detach_user = NULL;
1.225 djm 319: c->detach_close = 0;
1.275 djm 320: c->open_confirm = NULL;
321: c->open_confirm_ctx = NULL;
1.65 markus 322: c->input_filter = NULL;
1.231 reyk 323: c->output_filter = NULL;
1.280 djm 324: c->filter_ctx = NULL;
325: c->filter_cleanup = NULL;
1.299 markus 326: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 327: TAILQ_INIT(&c->status_confirms);
1.25 markus 328: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 329: return c;
1.1 deraadt 330: }
1.52 markus 331:
1.132 markus 332: static int
333: channel_find_maxfd(void)
334: {
1.209 avsm 335: u_int i;
336: int max = 0;
1.132 markus 337: Channel *c;
338:
339: for (i = 0; i < channels_alloc; i++) {
340: c = channels[i];
341: if (c != NULL) {
342: max = MAX(max, c->rfd);
343: max = MAX(max, c->wfd);
344: max = MAX(max, c->efd);
345: }
346: }
347: return max;
348: }
349:
350: int
351: channel_close_fd(int *fdp)
352: {
353: int ret = 0, fd = *fdp;
354:
355: if (fd != -1) {
356: ret = close(fd);
357: *fdp = -1;
358: if (fd == channel_max_fd)
359: channel_max_fd = channel_find_maxfd();
360: }
361: return ret;
362: }
363:
1.52 markus 364: /* Close all channel fd/socket. */
1.127 itojun 365: static void
1.52 markus 366: channel_close_fds(Channel *c)
367: {
1.204 djm 368: debug3("channel %d: close_fds r %d w %d e %d c %d",
369: c->self, c->rfd, c->wfd, c->efd, c->ctl_fd);
1.118 markus 370:
1.132 markus 371: channel_close_fd(&c->sock);
1.204 djm 372: channel_close_fd(&c->ctl_fd);
1.132 markus 373: channel_close_fd(&c->rfd);
374: channel_close_fd(&c->wfd);
375: channel_close_fd(&c->efd);
1.121 markus 376: }
377:
378: /* Free the channel and close its fd/socket. */
379: void
380: channel_free(Channel *c)
381: {
382: char *s;
1.209 avsm 383: u_int i, n;
1.275 djm 384: struct channel_confirm *cc;
1.121 markus 385:
386: for (n = 0, i = 0; i < channels_alloc; i++)
387: if (channels[i])
388: n++;
1.209 avsm 389: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 390: c->remote_name ? c->remote_name : "???", n);
391:
392: s = channel_open_message();
1.194 markus 393: debug3("channel %d: status: %s", c->self, s);
1.121 markus 394: xfree(s);
395:
396: if (c->sock != -1)
397: shutdown(c->sock, SHUT_RDWR);
1.204 djm 398: if (c->ctl_fd != -1)
399: shutdown(c->ctl_fd, SHUT_RDWR);
1.121 markus 400: channel_close_fds(c);
401: buffer_free(&c->input);
402: buffer_free(&c->output);
403: buffer_free(&c->extended);
404: if (c->remote_name) {
405: xfree(c->remote_name);
406: c->remote_name = NULL;
407: }
1.293 djm 408: if (c->path) {
409: xfree(c->path);
410: c->path = NULL;
411: }
1.275 djm 412: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
413: if (cc->abandon_cb != NULL)
414: cc->abandon_cb(c, cc->ctx);
415: TAILQ_REMOVE(&c->status_confirms, cc, entry);
416: bzero(cc, sizeof(*cc));
417: xfree(cc);
418: }
1.280 djm 419: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
420: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 421: channels[c->self] = NULL;
422: xfree(c);
423: }
424:
425: void
1.126 markus 426: channel_free_all(void)
1.121 markus 427: {
1.209 avsm 428: u_int i;
1.121 markus 429:
1.126 markus 430: for (i = 0; i < channels_alloc; i++)
431: if (channels[i] != NULL)
432: channel_free(channels[i]);
1.131 markus 433: }
434:
1.121 markus 435: /*
436: * Closes the sockets/fds of all channels. This is used to close extra file
437: * descriptors after a fork.
438: */
439: void
1.142 itojun 440: channel_close_all(void)
1.121 markus 441: {
1.209 avsm 442: u_int i;
1.121 markus 443:
444: for (i = 0; i < channels_alloc; i++)
445: if (channels[i] != NULL)
446: channel_close_fds(channels[i]);
447: }
448:
449: /*
1.131 markus 450: * Stop listening to channels.
451: */
452: void
453: channel_stop_listening(void)
454: {
1.209 avsm 455: u_int i;
1.131 markus 456: Channel *c;
457:
458: for (i = 0; i < channels_alloc; i++) {
459: c = channels[i];
460: if (c != NULL) {
461: switch (c->type) {
462: case SSH_CHANNEL_AUTH_SOCKET:
463: case SSH_CHANNEL_PORT_LISTENER:
464: case SSH_CHANNEL_RPORT_LISTENER:
465: case SSH_CHANNEL_X11_LISTENER:
1.132 markus 466: channel_close_fd(&c->sock);
1.131 markus 467: channel_free(c);
468: break;
469: }
470: }
471: }
472: }
473:
474: /*
1.121 markus 475: * Returns true if no channel has too much buffered data, and false if one or
476: * more channel is overfull.
477: */
478: int
1.142 itojun 479: channel_not_very_much_buffered_data(void)
1.121 markus 480: {
481: u_int i;
482: Channel *c;
483:
484: for (i = 0; i < channels_alloc; i++) {
485: c = channels[i];
486: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 487: #if 0
488: if (!compat20 &&
489: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 490: debug2("channel %d: big input buffer %d",
1.121 markus 491: c->self, buffer_len(&c->input));
492: return 0;
493: }
1.136 markus 494: #endif
1.121 markus 495: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 496: debug2("channel %d: big output buffer %u > %u",
1.136 markus 497: c->self, buffer_len(&c->output),
498: packet_get_maxsize());
1.121 markus 499: return 0;
500: }
501: }
502: }
503: return 1;
504: }
505:
506: /* Returns true if any channel is still open. */
507: int
1.142 itojun 508: channel_still_open(void)
1.121 markus 509: {
1.209 avsm 510: u_int i;
1.121 markus 511: Channel *c;
512:
513: for (i = 0; i < channels_alloc; i++) {
514: c = channels[i];
515: if (c == NULL)
516: continue;
517: switch (c->type) {
518: case SSH_CHANNEL_X11_LISTENER:
519: case SSH_CHANNEL_PORT_LISTENER:
520: case SSH_CHANNEL_RPORT_LISTENER:
521: case SSH_CHANNEL_CLOSED:
522: case SSH_CHANNEL_AUTH_SOCKET:
523: case SSH_CHANNEL_DYNAMIC:
524: case SSH_CHANNEL_CONNECTING:
525: case SSH_CHANNEL_ZOMBIE:
526: continue;
527: case SSH_CHANNEL_LARVAL:
528: if (!compat20)
529: fatal("cannot happen: SSH_CHANNEL_LARVAL");
530: continue;
531: case SSH_CHANNEL_OPENING:
532: case SSH_CHANNEL_OPEN:
533: case SSH_CHANNEL_X11_OPEN:
534: return 1;
535: case SSH_CHANNEL_INPUT_DRAINING:
536: case SSH_CHANNEL_OUTPUT_DRAINING:
537: if (!compat13)
538: fatal("cannot happen: OUT_DRAIN");
539: return 1;
540: default:
541: fatal("channel_still_open: bad channel type %d", c->type);
542: /* NOTREACHED */
543: }
544: }
545: return 0;
546: }
547:
548: /* Returns the id of an open channel suitable for keepaliving */
549: int
1.142 itojun 550: channel_find_open(void)
1.121 markus 551: {
1.209 avsm 552: u_int i;
1.121 markus 553: Channel *c;
554:
555: for (i = 0; i < channels_alloc; i++) {
556: c = channels[i];
1.206 djm 557: if (c == NULL || c->remote_id < 0)
1.121 markus 558: continue;
559: switch (c->type) {
560: case SSH_CHANNEL_CLOSED:
561: case SSH_CHANNEL_DYNAMIC:
562: case SSH_CHANNEL_X11_LISTENER:
563: case SSH_CHANNEL_PORT_LISTENER:
564: case SSH_CHANNEL_RPORT_LISTENER:
565: case SSH_CHANNEL_OPENING:
566: case SSH_CHANNEL_CONNECTING:
567: case SSH_CHANNEL_ZOMBIE:
568: continue;
569: case SSH_CHANNEL_LARVAL:
570: case SSH_CHANNEL_AUTH_SOCKET:
571: case SSH_CHANNEL_OPEN:
572: case SSH_CHANNEL_X11_OPEN:
573: return i;
574: case SSH_CHANNEL_INPUT_DRAINING:
575: case SSH_CHANNEL_OUTPUT_DRAINING:
576: if (!compat13)
577: fatal("cannot happen: OUT_DRAIN");
578: return i;
579: default:
580: fatal("channel_find_open: bad channel type %d", c->type);
581: /* NOTREACHED */
582: }
583: }
584: return -1;
585: }
586:
587:
588: /*
589: * Returns a message describing the currently open forwarded connections,
590: * suitable for sending to the client. The message contains crlf pairs for
591: * newlines.
592: */
593: char *
1.142 itojun 594: channel_open_message(void)
1.121 markus 595: {
596: Buffer buffer;
597: Channel *c;
598: char buf[1024], *cp;
1.209 avsm 599: u_int i;
1.121 markus 600:
601: buffer_init(&buffer);
602: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
603: buffer_append(&buffer, buf, strlen(buf));
604: for (i = 0; i < channels_alloc; i++) {
605: c = channels[i];
606: if (c == NULL)
607: continue;
608: switch (c->type) {
609: case SSH_CHANNEL_X11_LISTENER:
610: case SSH_CHANNEL_PORT_LISTENER:
611: case SSH_CHANNEL_RPORT_LISTENER:
612: case SSH_CHANNEL_CLOSED:
613: case SSH_CHANNEL_AUTH_SOCKET:
614: case SSH_CHANNEL_ZOMBIE:
615: continue;
616: case SSH_CHANNEL_LARVAL:
617: case SSH_CHANNEL_OPENING:
618: case SSH_CHANNEL_CONNECTING:
619: case SSH_CHANNEL_DYNAMIC:
620: case SSH_CHANNEL_OPEN:
621: case SSH_CHANNEL_X11_OPEN:
622: case SSH_CHANNEL_INPUT_DRAINING:
623: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 624: snprintf(buf, sizeof buf,
625: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cfd %d)\r\n",
1.121 markus 626: c->self, c->remote_name,
627: c->type, c->remote_id,
628: c->istate, buffer_len(&c->input),
629: c->ostate, buffer_len(&c->output),
1.204 djm 630: c->rfd, c->wfd, c->ctl_fd);
1.121 markus 631: buffer_append(&buffer, buf, strlen(buf));
632: continue;
633: default:
634: fatal("channel_open_message: bad channel type %d", c->type);
635: /* NOTREACHED */
636: }
637: }
638: buffer_append(&buffer, "\0", 1);
639: cp = xstrdup(buffer_ptr(&buffer));
640: buffer_free(&buffer);
641: return cp;
642: }
643:
644: void
645: channel_send_open(int id)
646: {
647: Channel *c = channel_lookup(id);
1.180 deraadt 648:
1.121 markus 649: if (c == NULL) {
1.188 itojun 650: logit("channel_send_open: %d: bad id", id);
1.121 markus 651: return;
652: }
1.184 markus 653: debug2("channel %d: send open", id);
1.121 markus 654: packet_start(SSH2_MSG_CHANNEL_OPEN);
655: packet_put_cstring(c->ctype);
656: packet_put_int(c->self);
657: packet_put_int(c->local_window);
658: packet_put_int(c->local_maxpacket);
659: packet_send();
660: }
661:
662: void
1.184 markus 663: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 664: {
1.184 markus 665: Channel *c = channel_lookup(id);
1.180 deraadt 666:
1.121 markus 667: if (c == NULL) {
1.188 itojun 668: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 669: return;
670: }
1.204 djm 671: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 672: packet_start(SSH2_MSG_CHANNEL_REQUEST);
673: packet_put_int(c->remote_id);
674: packet_put_cstring(service);
675: packet_put_char(wantconfirm);
676: }
1.241 deraadt 677:
1.121 markus 678: void
1.275 djm 679: channel_register_status_confirm(int id, channel_confirm_cb *cb,
680: channel_confirm_abandon_cb *abandon_cb, void *ctx)
681: {
682: struct channel_confirm *cc;
683: Channel *c;
684:
685: if ((c = channel_lookup(id)) == NULL)
686: fatal("channel_register_expect: %d: bad id", id);
687:
688: cc = xmalloc(sizeof(*cc));
689: cc->cb = cb;
690: cc->abandon_cb = abandon_cb;
691: cc->ctx = ctx;
692: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
693: }
694:
695: void
696: channel_register_open_confirm(int id, channel_callback_fn *fn, void *ctx)
1.121 markus 697: {
698: Channel *c = channel_lookup(id);
1.180 deraadt 699:
1.121 markus 700: if (c == NULL) {
1.287 stevesk 701: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 702: return;
703: }
1.275 djm 704: c->open_confirm = fn;
705: c->open_confirm_ctx = ctx;
1.121 markus 706: }
1.241 deraadt 707:
1.121 markus 708: void
1.225 djm 709: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 710: {
1.229 markus 711: Channel *c = channel_by_id(id);
1.180 deraadt 712:
1.121 markus 713: if (c == NULL) {
1.188 itojun 714: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 715: return;
716: }
1.131 markus 717: c->detach_user = fn;
1.225 djm 718: c->detach_close = do_close;
1.121 markus 719: }
1.241 deraadt 720:
1.121 markus 721: void
722: channel_cancel_cleanup(int id)
723: {
1.229 markus 724: Channel *c = channel_by_id(id);
1.180 deraadt 725:
1.121 markus 726: if (c == NULL) {
1.188 itojun 727: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 728: return;
1.52 markus 729: }
1.131 markus 730: c->detach_user = NULL;
1.225 djm 731: c->detach_close = 0;
1.121 markus 732: }
1.241 deraadt 733:
1.121 markus 734: void
1.231 reyk 735: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 736: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 737: {
738: Channel *c = channel_lookup(id);
1.180 deraadt 739:
1.121 markus 740: if (c == NULL) {
1.188 itojun 741: logit("channel_register_filter: %d: bad id", id);
1.121 markus 742: return;
1.52 markus 743: }
1.231 reyk 744: c->input_filter = ifn;
745: c->output_filter = ofn;
1.279 djm 746: c->filter_ctx = ctx;
1.280 djm 747: c->filter_cleanup = cfn;
1.52 markus 748: }
749:
1.49 markus 750: void
1.121 markus 751: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 752: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 753: {
1.121 markus 754: Channel *c = channel_lookup(id);
1.180 deraadt 755:
1.121 markus 756: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
757: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 758: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 759: c->type = SSH_CHANNEL_OPEN;
1.168 markus 760: c->local_window = c->local_window_max = window_max;
1.121 markus 761: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
762: packet_put_int(c->remote_id);
763: packet_put_int(c->local_window);
764: packet_send();
1.1 deraadt 765: }
766:
1.27 markus 767: /*
1.41 markus 768: * 'channel_pre*' are called just before select() to add any bits relevant to
769: * channels in the select bitmasks.
770: */
771: /*
772: * 'channel_post*': perform any appropriate operations for channels which
773: * have events pending.
1.27 markus 774: */
1.237 deraadt 775: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 776: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
777: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
778:
1.259 stevesk 779: /* ARGSUSED */
1.127 itojun 780: static void
1.237 deraadt 781: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 782: {
783: FD_SET(c->sock, readset);
784: }
785:
1.259 stevesk 786: /* ARGSUSED */
1.127 itojun 787: static void
1.237 deraadt 788: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 789: {
790: debug3("channel %d: waiting for connection", c->self);
791: FD_SET(c->sock, writeset);
792: }
793:
1.127 itojun 794: static void
1.237 deraadt 795: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 796: {
797: if (buffer_len(&c->input) < packet_get_maxsize())
798: FD_SET(c->sock, readset);
799: if (buffer_len(&c->output) > 0)
800: FD_SET(c->sock, writeset);
801: }
1.1 deraadt 802:
1.127 itojun 803: static void
1.237 deraadt 804: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 805: {
1.157 markus 806: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 807:
1.44 markus 808: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 809: limit > 0 &&
1.250 djm 810: buffer_len(&c->input) < limit &&
811: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 812: FD_SET(c->rfd, readset);
813: if (c->ostate == CHAN_OUTPUT_OPEN ||
814: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
815: if (buffer_len(&c->output) > 0) {
816: FD_SET(c->wfd, writeset);
817: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 818: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 819: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
820: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 821: else
822: chan_obuf_empty(c);
1.44 markus 823: }
824: }
825: /** XXX check close conditions, too */
1.277 markus 826: if (compat20 && c->efd != -1 &&
827: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 828: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
829: buffer_len(&c->extended) > 0)
830: FD_SET(c->efd, writeset);
1.172 markus 831: else if (!(c->flags & CHAN_EOF_SENT) &&
832: c->extended_usage == CHAN_EXTENDED_READ &&
1.44 markus 833: buffer_len(&c->extended) < c->remote_window)
834: FD_SET(c->efd, readset);
835: }
1.204 djm 836: /* XXX: What about efd? races? */
1.208 deraadt 837: if (compat20 && c->ctl_fd != -1 &&
1.204 djm 838: c->istate == CHAN_INPUT_OPEN && c->ostate == CHAN_OUTPUT_OPEN)
839: FD_SET(c->ctl_fd, readset);
1.44 markus 840: }
841:
1.259 stevesk 842: /* ARGSUSED */
1.127 itojun 843: static void
1.237 deraadt 844: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 845: {
846: if (buffer_len(&c->input) == 0) {
847: packet_start(SSH_MSG_CHANNEL_CLOSE);
848: packet_put_int(c->remote_id);
849: packet_send();
850: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 851: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 852: }
853: }
854:
1.259 stevesk 855: /* ARGSUSED */
1.127 itojun 856: static void
1.237 deraadt 857: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 858: {
859: if (buffer_len(&c->output) == 0)
1.113 markus 860: chan_mark_dead(c);
1.49 markus 861: else
1.41 markus 862: FD_SET(c->sock, writeset);
863: }
864:
865: /*
866: * This is a special state for X11 authentication spoofing. An opened X11
867: * connection (when authentication spoofing is being done) remains in this
868: * state until the first packet has been completely read. The authentication
869: * data in that packet is then substituted by the real data if it matches the
870: * fake data, and the channel is put into normal mode.
1.51 markus 871: * XXX All this happens at the client side.
1.121 markus 872: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 873: */
1.127 itojun 874: static int
1.121 markus 875: x11_open_helper(Buffer *b)
1.1 deraadt 876: {
1.77 markus 877: u_char *ucp;
878: u_int proto_len, data_len;
1.25 markus 879:
1.41 markus 880: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 881: if (buffer_len(b) < 12)
1.41 markus 882: return 0;
883:
884: /* Parse the lengths of variable-length fields. */
1.155 stevesk 885: ucp = buffer_ptr(b);
1.41 markus 886: if (ucp[0] == 0x42) { /* Byte order MSB first. */
887: proto_len = 256 * ucp[6] + ucp[7];
888: data_len = 256 * ucp[8] + ucp[9];
889: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
890: proto_len = ucp[6] + 256 * ucp[7];
891: data_len = ucp[8] + 256 * ucp[9];
892: } else {
1.194 markus 893: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 894: ucp[0]);
1.41 markus 895: return -1;
896: }
897:
898: /* Check if the whole packet is in buffer. */
1.121 markus 899: if (buffer_len(b) <
1.41 markus 900: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
901: return 0;
902:
903: /* Check if authentication protocol matches. */
904: if (proto_len != strlen(x11_saved_proto) ||
905: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 906: debug2("X11 connection uses different authentication protocol.");
1.41 markus 907: return -1;
908: }
909: /* Check if authentication data matches our fake data. */
910: if (data_len != x11_fake_data_len ||
911: memcmp(ucp + 12 + ((proto_len + 3) & ~3),
912: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 913: debug2("X11 auth data does not match fake data.");
1.41 markus 914: return -1;
915: }
916: /* Check fake data length */
917: if (x11_fake_data_len != x11_saved_data_len) {
918: error("X11 fake_data_len %d != saved_data_len %d",
919: x11_fake_data_len, x11_saved_data_len);
920: return -1;
921: }
922: /*
923: * Received authentication protocol and data match
924: * our fake data. Substitute the fake data with real
925: * data.
926: */
927: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
928: x11_saved_data, x11_saved_data_len);
929: return 1;
930: }
931:
1.127 itojun 932: static void
1.237 deraadt 933: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 934: {
1.121 markus 935: int ret = x11_open_helper(&c->output);
1.180 deraadt 936:
1.41 markus 937: if (ret == 1) {
938: /* Start normal processing for the channel. */
939: c->type = SSH_CHANNEL_OPEN;
1.47 markus 940: channel_pre_open_13(c, readset, writeset);
1.41 markus 941: } else if (ret == -1) {
942: /*
943: * We have received an X11 connection that has bad
944: * authentication information.
945: */
1.188 itojun 946: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 947: buffer_clear(&c->input);
948: buffer_clear(&c->output);
1.132 markus 949: channel_close_fd(&c->sock);
1.41 markus 950: c->sock = -1;
951: c->type = SSH_CHANNEL_CLOSED;
952: packet_start(SSH_MSG_CHANNEL_CLOSE);
953: packet_put_int(c->remote_id);
954: packet_send();
955: }
956: }
1.25 markus 957:
1.127 itojun 958: static void
1.237 deraadt 959: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 960: {
1.121 markus 961: int ret = x11_open_helper(&c->output);
1.133 markus 962:
963: /* c->force_drain = 1; */
964:
1.41 markus 965: if (ret == 1) {
966: c->type = SSH_CHANNEL_OPEN;
1.157 markus 967: channel_pre_open(c, readset, writeset);
1.41 markus 968: } else if (ret == -1) {
1.188 itojun 969: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 970: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 971: chan_read_failed(c);
972: buffer_clear(&c->input);
973: chan_ibuf_empty(c);
974: buffer_clear(&c->output);
975: /* for proto v1, the peer will send an IEOF */
976: if (compat20)
977: chan_write_failed(c);
978: else
979: c->type = SSH_CHANNEL_OPEN;
1.194 markus 980: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 981: }
982: }
1.25 markus 983:
1.104 markus 984: /* try to decode a socks4 header */
1.259 stevesk 985: /* ARGSUSED */
1.127 itojun 986: static int
1.237 deraadt 987: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 988: {
1.181 markus 989: char *p, *host;
1.292 djm 990: u_int len, have, i, found, need;
1.148 deraadt 991: char username[256];
1.103 markus 992: struct {
993: u_int8_t version;
994: u_int8_t command;
995: u_int16_t dest_port;
1.104 markus 996: struct in_addr dest_addr;
1.103 markus 997: } s4_req, s4_rsp;
998:
1.104 markus 999: debug2("channel %d: decode socks4", c->self);
1.109 markus 1000:
1001: have = buffer_len(&c->input);
1002: len = sizeof(s4_req);
1003: if (have < len)
1004: return 0;
1005: p = buffer_ptr(&c->input);
1.292 djm 1006:
1007: need = 1;
1008: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1009: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1010: debug2("channel %d: socks4a request", c->self);
1011: /* ... and needs an extra string (the hostname) */
1012: need = 2;
1013: }
1014: /* Check for terminating NUL on the string(s) */
1.109 markus 1015: for (found = 0, i = len; i < have; i++) {
1016: if (p[i] == '\0') {
1.292 djm 1017: found++;
1018: if (found == need)
1019: break;
1.109 markus 1020: }
1021: if (i > 1024) {
1022: /* the peer is probably sending garbage */
1023: debug("channel %d: decode socks4: too long",
1024: c->self);
1025: return -1;
1026: }
1027: }
1.292 djm 1028: if (found < need)
1.109 markus 1029: return 0;
1.103 markus 1030: buffer_get(&c->input, (char *)&s4_req.version, 1);
1031: buffer_get(&c->input, (char *)&s4_req.command, 1);
1032: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1033: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1034: have = buffer_len(&c->input);
1.103 markus 1035: p = buffer_ptr(&c->input);
1036: len = strlen(p);
1.106 markus 1037: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1038: len++; /* trailing '\0' */
1.103 markus 1039: if (len > have)
1.104 markus 1040: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1041: c->self, len, have);
1042: strlcpy(username, p, sizeof(username));
1043: buffer_consume(&c->input, len);
1044:
1.293 djm 1045: if (c->path != NULL) {
1046: xfree(c->path);
1047: c->path = NULL;
1048: }
1.292 djm 1049: if (need == 1) { /* SOCKS4: one string */
1050: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1051: c->path = xstrdup(host);
1.292 djm 1052: } else { /* SOCKS4A: two strings */
1053: have = buffer_len(&c->input);
1054: p = buffer_ptr(&c->input);
1055: len = strlen(p);
1056: debug2("channel %d: decode socks4a: host %s/%d",
1057: c->self, p, len);
1058: len++; /* trailing '\0' */
1059: if (len > have)
1060: fatal("channel %d: decode socks4a: len %d > have %d",
1061: c->self, len, have);
1.293 djm 1062: if (len > NI_MAXHOST) {
1.292 djm 1063: error("channel %d: hostname \"%.100s\" too long",
1064: c->self, p);
1065: return -1;
1066: }
1.293 djm 1067: c->path = xstrdup(p);
1.292 djm 1068: buffer_consume(&c->input, len);
1069: }
1.103 markus 1070: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1071:
1.194 markus 1072: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1073: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1074:
1.104 markus 1075: if (s4_req.command != 1) {
1.292 djm 1076: debug("channel %d: cannot handle: %s cn %d",
1077: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1078: return -1;
1.103 markus 1079: }
1.104 markus 1080: s4_rsp.version = 0; /* vn: 0 for reply */
1081: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1082: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1083: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1084: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1085: return 1;
1086: }
1087:
1.193 markus 1088: /* try to decode a socks5 header */
1089: #define SSH_SOCKS5_AUTHDONE 0x1000
1090: #define SSH_SOCKS5_NOAUTH 0x00
1091: #define SSH_SOCKS5_IPV4 0x01
1092: #define SSH_SOCKS5_DOMAIN 0x03
1093: #define SSH_SOCKS5_IPV6 0x04
1094: #define SSH_SOCKS5_CONNECT 0x01
1095: #define SSH_SOCKS5_SUCCESS 0x00
1096:
1.259 stevesk 1097: /* ARGSUSED */
1.193 markus 1098: static int
1.237 deraadt 1099: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1100: {
1101: struct {
1102: u_int8_t version;
1103: u_int8_t command;
1104: u_int8_t reserved;
1105: u_int8_t atyp;
1106: } s5_req, s5_rsp;
1107: u_int16_t dest_port;
1.293 djm 1108: u_char *p, dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.252 djm 1109: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1110:
1111: debug2("channel %d: decode socks5", c->self);
1112: p = buffer_ptr(&c->input);
1113: if (p[0] != 0x05)
1114: return -1;
1115: have = buffer_len(&c->input);
1116: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1117: /* format: ver | nmethods | methods */
1.198 djm 1118: if (have < 2)
1.193 markus 1119: return 0;
1120: nmethods = p[1];
1121: if (have < nmethods + 2)
1122: return 0;
1123: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1124: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1125: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1126: found = 1;
1127: break;
1128: }
1129: }
1130: if (!found) {
1131: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1132: c->self);
1133: return -1;
1134: }
1135: buffer_consume(&c->input, nmethods + 2);
1136: buffer_put_char(&c->output, 0x05); /* version */
1137: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1138: FD_SET(c->sock, writeset);
1139: c->flags |= SSH_SOCKS5_AUTHDONE;
1140: debug2("channel %d: socks5 auth done", c->self);
1141: return 0; /* need more */
1142: }
1143: debug2("channel %d: socks5 post auth", c->self);
1144: if (have < sizeof(s5_req)+1)
1145: return 0; /* need more */
1.247 deraadt 1146: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1147: if (s5_req.version != 0x05 ||
1148: s5_req.command != SSH_SOCKS5_CONNECT ||
1149: s5_req.reserved != 0x00) {
1.194 markus 1150: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1151: return -1;
1152: }
1.213 deraadt 1153: switch (s5_req.atyp){
1.193 markus 1154: case SSH_SOCKS5_IPV4:
1155: addrlen = 4;
1156: af = AF_INET;
1157: break;
1158: case SSH_SOCKS5_DOMAIN:
1159: addrlen = p[sizeof(s5_req)];
1160: af = -1;
1161: break;
1162: case SSH_SOCKS5_IPV6:
1163: addrlen = 16;
1164: af = AF_INET6;
1165: break;
1166: default:
1.194 markus 1167: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1168: return -1;
1169: }
1.252 djm 1170: need = sizeof(s5_req) + addrlen + 2;
1171: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1172: need++;
1173: if (have < need)
1.193 markus 1174: return 0;
1175: buffer_consume(&c->input, sizeof(s5_req));
1176: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1177: buffer_consume(&c->input, 1); /* host string length */
1178: buffer_get(&c->input, (char *)&dest_addr, addrlen);
1179: buffer_get(&c->input, (char *)&dest_port, 2);
1180: dest_addr[addrlen] = '\0';
1.293 djm 1181: if (c->path != NULL) {
1182: xfree(c->path);
1183: c->path = NULL;
1184: }
1185: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1186: if (addrlen >= NI_MAXHOST) {
1.293 djm 1187: error("channel %d: dynamic request: socks5 hostname "
1188: "\"%.100s\" too long", c->self, dest_addr);
1189: return -1;
1190: }
1191: c->path = xstrdup(dest_addr);
1192: } else {
1193: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1194: return -1;
1195: c->path = xstrdup(ntop);
1196: }
1.193 markus 1197: c->host_port = ntohs(dest_port);
1.198 djm 1198:
1.194 markus 1199: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1200: c->self, c->path, c->host_port, s5_req.command);
1201:
1202: s5_rsp.version = 0x05;
1203: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1204: s5_rsp.reserved = 0; /* ignored */
1205: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1206: ((struct in_addr *)&dest_addr)->s_addr = INADDR_ANY;
1207: dest_port = 0; /* ignored */
1208:
1.246 deraadt 1209: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1210: buffer_append(&c->output, &dest_addr, sizeof(struct in_addr));
1211: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1212: return 1;
1.301 ! dtucker 1213: }
! 1214:
! 1215: Channel *
! 1216: channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
! 1217: {
! 1218: Channel *c;
! 1219: int in, out;
! 1220:
! 1221: debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
! 1222: port_to_connect);
! 1223:
! 1224: in = dup(STDIN_FILENO);
! 1225: out = dup(STDOUT_FILENO);
! 1226: if (in < 0 || out < 0)
! 1227: fatal("channel_connect_stdio_fwd: dup() in/out failed");
! 1228:
! 1229: c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
! 1230: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
! 1231: 0, "stdio-forward", /*nonblock*/0);
! 1232:
! 1233: c->path = xstrdup(host_to_connect);
! 1234: c->host_port = port_to_connect;
! 1235: c->listening_port = 0;
! 1236: c->force_drain = 1;
! 1237:
! 1238: channel_register_fds(c, in, out, -1, 0, 1, 0);
! 1239: port_open_helper(c, "direct-tcpip");
! 1240:
! 1241: return c;
1.193 markus 1242: }
1243:
1.104 markus 1244: /* dynamic port forwarding */
1.127 itojun 1245: static void
1.237 deraadt 1246: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1247: {
1248: u_char *p;
1.217 djm 1249: u_int have;
1250: int ret;
1.103 markus 1251:
1.104 markus 1252: have = buffer_len(&c->input);
1253: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1254: /* buffer_dump(&c->input); */
1.104 markus 1255: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1256: if (have < 3) {
1.104 markus 1257: /* need more */
1258: FD_SET(c->sock, readset);
1259: return;
1260: }
1261: /* try to guess the protocol */
1262: p = buffer_ptr(&c->input);
1263: switch (p[0]) {
1264: case 0x04:
1265: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1266: break;
1267: case 0x05:
1268: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1269: break;
1270: default:
1271: ret = -1;
1272: break;
1273: }
1274: if (ret < 0) {
1.113 markus 1275: chan_mark_dead(c);
1.104 markus 1276: } else if (ret == 0) {
1277: debug2("channel %d: pre_dynamic: need more", c->self);
1278: /* need more */
1279: FD_SET(c->sock, readset);
1280: } else {
1281: /* switch to the next state */
1282: c->type = SSH_CHANNEL_OPENING;
1283: port_open_helper(c, "direct-tcpip");
1284: }
1.103 markus 1285: }
1286:
1.41 markus 1287: /* This is our fake X11 server socket. */
1.259 stevesk 1288: /* ARGSUSED */
1.127 itojun 1289: static void
1.237 deraadt 1290: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1291: {
1.113 markus 1292: Channel *nc;
1.285 djm 1293: struct sockaddr_storage addr;
1.162 stevesk 1294: int newsock;
1.41 markus 1295: socklen_t addrlen;
1.85 markus 1296: char buf[16384], *remote_ipaddr;
1.51 markus 1297: int remote_port;
1.25 markus 1298:
1.41 markus 1299: if (FD_ISSET(c->sock, readset)) {
1300: debug("X11 connection requested.");
1301: addrlen = sizeof(addr);
1.285 djm 1302: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1303: if (c->single_connection) {
1.194 markus 1304: debug2("single_connection: closing X11 listener.");
1.149 markus 1305: channel_close_fd(&c->sock);
1306: chan_mark_dead(c);
1307: }
1.41 markus 1308: if (newsock < 0) {
1309: error("accept: %.100s", strerror(errno));
1310: return;
1311: }
1.162 stevesk 1312: set_nodelay(newsock);
1.85 markus 1313: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1314: remote_port = get_peer_port(newsock);
1.41 markus 1315: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1316: remote_ipaddr, remote_port);
1.51 markus 1317:
1.113 markus 1318: nc = channel_new("accepted x11 socket",
1.51 markus 1319: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1320: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1321: if (compat20) {
1322: packet_start(SSH2_MSG_CHANNEL_OPEN);
1323: packet_put_cstring("x11");
1.113 markus 1324: packet_put_int(nc->self);
1.149 markus 1325: packet_put_int(nc->local_window_max);
1326: packet_put_int(nc->local_maxpacket);
1.85 markus 1327: /* originator ipaddr and port */
1328: packet_put_cstring(remote_ipaddr);
1.57 markus 1329: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1330: debug2("ssh2 x11 bug compat mode");
1.57 markus 1331: } else {
1332: packet_put_int(remote_port);
1333: }
1.51 markus 1334: packet_send();
1335: } else {
1336: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1337: packet_put_int(nc->self);
1.121 markus 1338: if (packet_get_protocol_flags() &
1339: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1340: packet_put_cstring(buf);
1.51 markus 1341: packet_send();
1342: }
1.85 markus 1343: xfree(remote_ipaddr);
1.41 markus 1344: }
1345: }
1.25 markus 1346:
1.127 itojun 1347: static void
1.103 markus 1348: port_open_helper(Channel *c, char *rtype)
1349: {
1350: int direct;
1351: char buf[1024];
1352: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1353: int remote_port = get_peer_port(c->sock);
1.103 markus 1354:
1355: direct = (strcmp(rtype, "direct-tcpip") == 0);
1356:
1357: snprintf(buf, sizeof buf,
1358: "%s: listening port %d for %.100s port %d, "
1359: "connect from %.200s port %d",
1360: rtype, c->listening_port, c->path, c->host_port,
1361: remote_ipaddr, remote_port);
1362:
1363: xfree(c->remote_name);
1364: c->remote_name = xstrdup(buf);
1365:
1366: if (compat20) {
1367: packet_start(SSH2_MSG_CHANNEL_OPEN);
1368: packet_put_cstring(rtype);
1369: packet_put_int(c->self);
1370: packet_put_int(c->local_window_max);
1371: packet_put_int(c->local_maxpacket);
1372: if (direct) {
1373: /* target host, port */
1374: packet_put_cstring(c->path);
1375: packet_put_int(c->host_port);
1376: } else {
1377: /* listen address, port */
1378: packet_put_cstring(c->path);
1379: packet_put_int(c->listening_port);
1380: }
1381: /* originator host and port */
1382: packet_put_cstring(remote_ipaddr);
1.216 markus 1383: packet_put_int((u_int)remote_port);
1.103 markus 1384: packet_send();
1385: } else {
1386: packet_start(SSH_MSG_PORT_OPEN);
1387: packet_put_int(c->self);
1388: packet_put_cstring(c->path);
1389: packet_put_int(c->host_port);
1.121 markus 1390: if (packet_get_protocol_flags() &
1391: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1392: packet_put_cstring(c->remote_name);
1393: packet_send();
1394: }
1395: xfree(remote_ipaddr);
1396: }
1397:
1.226 djm 1398: static void
1399: channel_set_reuseaddr(int fd)
1400: {
1401: int on = 1;
1402:
1403: /*
1404: * Set socket options.
1405: * Allow local port reuse in TIME_WAIT.
1406: */
1407: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1408: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1409: }
1410:
1.41 markus 1411: /*
1412: * This socket is listening for connections to a forwarded TCP/IP port.
1413: */
1.259 stevesk 1414: /* ARGSUSED */
1.127 itojun 1415: static void
1.237 deraadt 1416: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1417: {
1.103 markus 1418: Channel *nc;
1.285 djm 1419: struct sockaddr_storage addr;
1.113 markus 1420: int newsock, nextstate;
1.41 markus 1421: socklen_t addrlen;
1.103 markus 1422: char *rtype;
1.73 markus 1423:
1.41 markus 1424: if (FD_ISSET(c->sock, readset)) {
1425: debug("Connection to port %d forwarding "
1426: "to %.100s port %d requested.",
1427: c->listening_port, c->path, c->host_port);
1.103 markus 1428:
1.137 markus 1429: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1430: nextstate = SSH_CHANNEL_OPENING;
1431: rtype = "forwarded-tcpip";
1432: } else {
1433: if (c->host_port == 0) {
1434: nextstate = SSH_CHANNEL_DYNAMIC;
1.138 markus 1435: rtype = "dynamic-tcpip";
1.137 markus 1436: } else {
1437: nextstate = SSH_CHANNEL_OPENING;
1438: rtype = "direct-tcpip";
1439: }
1440: }
1.103 markus 1441:
1.41 markus 1442: addrlen = sizeof(addr);
1.285 djm 1443: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1444: if (newsock < 0) {
1445: error("accept: %.100s", strerror(errno));
1446: return;
1447: }
1.169 stevesk 1448: set_nodelay(newsock);
1.190 markus 1449: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1450: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1451: nc->listening_port = c->listening_port;
1452: nc->host_port = c->host_port;
1.293 djm 1453: if (c->path != NULL)
1454: nc->path = xstrdup(c->path);
1.103 markus 1455:
1.299 markus 1456: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1457: port_open_helper(nc, rtype);
1.41 markus 1458: }
1459: }
1.25 markus 1460:
1.41 markus 1461: /*
1462: * This is the authentication agent socket listening for connections from
1463: * clients.
1464: */
1.259 stevesk 1465: /* ARGSUSED */
1.127 itojun 1466: static void
1.237 deraadt 1467: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1468: {
1.113 markus 1469: Channel *nc;
1470: int newsock;
1.285 djm 1471: struct sockaddr_storage addr;
1.41 markus 1472: socklen_t addrlen;
1.25 markus 1473:
1.41 markus 1474: if (FD_ISSET(c->sock, readset)) {
1475: addrlen = sizeof(addr);
1.285 djm 1476: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1477: if (newsock < 0) {
1478: error("accept from auth socket: %.100s", strerror(errno));
1479: return;
1480: }
1.113 markus 1481: nc = channel_new("accepted auth socket",
1.73 markus 1482: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1483: c->local_window_max, c->local_maxpacket,
1.190 markus 1484: 0, "accepted auth socket", 1);
1.73 markus 1485: if (compat20) {
1486: packet_start(SSH2_MSG_CHANNEL_OPEN);
1487: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1488: packet_put_int(nc->self);
1.73 markus 1489: packet_put_int(c->local_window_max);
1490: packet_put_int(c->local_maxpacket);
1491: } else {
1492: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1493: packet_put_int(nc->self);
1.73 markus 1494: }
1.41 markus 1495: packet_send();
1496: }
1497: }
1.25 markus 1498:
1.259 stevesk 1499: /* ARGSUSED */
1.127 itojun 1500: static void
1.237 deraadt 1501: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1502: {
1.276 djm 1503: int err = 0, sock;
1.129 stevesk 1504: socklen_t sz = sizeof(err);
1.114 markus 1505:
1.75 markus 1506: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1507: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1508: err = errno;
1509: error("getsockopt SO_ERROR failed");
1510: }
1511: if (err == 0) {
1.276 djm 1512: debug("channel %d: connected to %s port %d",
1513: c->self, c->connect_ctx.host, c->connect_ctx.port);
1514: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1515: c->type = SSH_CHANNEL_OPEN;
1516: if (compat20) {
1517: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1518: packet_put_int(c->remote_id);
1519: packet_put_int(c->self);
1520: packet_put_int(c->local_window);
1521: packet_put_int(c->local_maxpacket);
1522: } else {
1523: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1524: packet_put_int(c->remote_id);
1525: packet_put_int(c->self);
1526: }
1.75 markus 1527: } else {
1.276 djm 1528: debug("channel %d: connection failed: %s",
1.114 markus 1529: c->self, strerror(err));
1.276 djm 1530: /* Try next address, if any */
1531: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1532: close(c->sock);
1533: c->sock = c->rfd = c->wfd = sock;
1534: channel_max_fd = channel_find_maxfd();
1535: return;
1536: }
1537: /* Exhausted all addresses */
1538: error("connect_to %.100s port %d: failed.",
1539: c->connect_ctx.host, c->connect_ctx.port);
1540: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1541: if (compat20) {
1542: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1543: packet_put_int(c->remote_id);
1544: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1545: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1546: packet_put_cstring(strerror(err));
1547: packet_put_cstring("");
1548: }
1.75 markus 1549: } else {
1.114 markus 1550: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1551: packet_put_int(c->remote_id);
1.75 markus 1552: }
1.114 markus 1553: chan_mark_dead(c);
1.75 markus 1554: }
1.114 markus 1555: packet_send();
1.75 markus 1556: }
1557: }
1558:
1.259 stevesk 1559: /* ARGSUSED */
1.127 itojun 1560: static int
1.237 deraadt 1561: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1562: {
1.214 markus 1563: char buf[CHAN_RBUF];
1.41 markus 1564: int len;
1.25 markus 1565:
1.118 markus 1566: if (c->rfd != -1 &&
1.41 markus 1567: FD_ISSET(c->rfd, readset)) {
1568: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1569: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1570: return 1;
1.41 markus 1571: if (len <= 0) {
1.194 markus 1572: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1573: c->self, c->rfd, len);
1.104 markus 1574: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1575: debug2("channel %d: not open", c->self);
1.113 markus 1576: chan_mark_dead(c);
1.103 markus 1577: return -1;
1.104 markus 1578: } else if (compat13) {
1.158 markus 1579: buffer_clear(&c->output);
1.41 markus 1580: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1581: debug2("channel %d: input draining.", c->self);
1.25 markus 1582: } else {
1.41 markus 1583: chan_read_failed(c);
1.25 markus 1584: }
1.41 markus 1585: return -1;
1586: }
1.143 deraadt 1587: if (c->input_filter != NULL) {
1.66 markus 1588: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1589: debug2("channel %d: filter stops", c->self);
1.65 markus 1590: chan_read_failed(c);
1591: }
1.228 reyk 1592: } else if (c->datagram) {
1593: buffer_put_string(&c->input, buf, len);
1.65 markus 1594: } else {
1595: buffer_append(&c->input, buf, len);
1596: }
1.41 markus 1597: }
1598: return 1;
1599: }
1.241 deraadt 1600:
1.259 stevesk 1601: /* ARGSUSED */
1.127 itojun 1602: static int
1.237 deraadt 1603: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1604: {
1.95 markus 1605: struct termios tio;
1.231 reyk 1606: u_char *data = NULL, *buf;
1.134 markus 1607: u_int dlen;
1.41 markus 1608: int len;
1.25 markus 1609:
1.41 markus 1610: /* Send buffered output data to the socket. */
1.118 markus 1611: if (c->wfd != -1 &&
1.41 markus 1612: FD_ISSET(c->wfd, writeset) &&
1613: buffer_len(&c->output) > 0) {
1.231 reyk 1614: if (c->output_filter != NULL) {
1615: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1616: debug2("channel %d: filter stops", c->self);
1.232 reyk 1617: if (c->type != SSH_CHANNEL_OPEN)
1618: chan_mark_dead(c);
1619: else
1620: chan_write_failed(c);
1621: return -1;
1.231 reyk 1622: }
1623: } else if (c->datagram) {
1624: buf = data = buffer_get_string(&c->output, &dlen);
1625: } else {
1626: buf = data = buffer_ptr(&c->output);
1627: dlen = buffer_len(&c->output);
1628: }
1629:
1.228 reyk 1630: if (c->datagram) {
1631: /* ignore truncated writes, datagrams might get lost */
1632: c->local_consumed += dlen + 4;
1.231 reyk 1633: len = write(c->wfd, buf, dlen);
1.228 reyk 1634: xfree(data);
1635: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1636: return 1;
1637: if (len <= 0) {
1638: if (c->type != SSH_CHANNEL_OPEN)
1639: chan_mark_dead(c);
1640: else
1641: chan_write_failed(c);
1642: return -1;
1643: }
1644: return 1;
1645: }
1.231 reyk 1646:
1647: len = write(c->wfd, buf, dlen);
1.53 markus 1648: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1649: return 1;
1.41 markus 1650: if (len <= 0) {
1.104 markus 1651: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1652: debug2("channel %d: not open", c->self);
1.113 markus 1653: chan_mark_dead(c);
1.104 markus 1654: return -1;
1655: } else if (compat13) {
1.158 markus 1656: buffer_clear(&c->output);
1.194 markus 1657: debug2("channel %d: input draining.", c->self);
1.41 markus 1658: c->type = SSH_CHANNEL_INPUT_DRAINING;
1659: } else {
1660: chan_write_failed(c);
1661: }
1662: return -1;
1.91 markus 1663: }
1.231 reyk 1664: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1665: if (tcgetattr(c->wfd, &tio) == 0 &&
1666: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1667: /*
1668: * Simulate echo to reduce the impact of
1.96 markus 1669: * traffic analysis. We need to match the
1.95 markus 1670: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1671: * (4 byte channel id + buf)
1.91 markus 1672: */
1.95 markus 1673: packet_send_ignore(4 + len);
1.91 markus 1674: packet_send();
1675: }
1.25 markus 1676: }
1.41 markus 1677: buffer_consume(&c->output, len);
1.44 markus 1678: if (compat20 && len > 0) {
1679: c->local_consumed += len;
1680: }
1681: }
1682: return 1;
1683: }
1.241 deraadt 1684:
1.127 itojun 1685: static int
1.237 deraadt 1686: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1687: {
1.214 markus 1688: char buf[CHAN_RBUF];
1.44 markus 1689: int len;
1690:
1.45 markus 1691: /** XXX handle drain efd, too */
1.44 markus 1692: if (c->efd != -1) {
1693: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1694: FD_ISSET(c->efd, writeset) &&
1695: buffer_len(&c->extended) > 0) {
1696: len = write(c->efd, buffer_ptr(&c->extended),
1697: buffer_len(&c->extended));
1.70 markus 1698: debug2("channel %d: written %d to efd %d",
1.44 markus 1699: c->self, len, c->efd);
1.93 markus 1700: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1701: return 1;
1702: if (len <= 0) {
1703: debug2("channel %d: closing write-efd %d",
1704: c->self, c->efd);
1.132 markus 1705: channel_close_fd(&c->efd);
1.93 markus 1706: } else {
1.44 markus 1707: buffer_consume(&c->extended, len);
1708: c->local_consumed += len;
1709: }
1710: } else if (c->extended_usage == CHAN_EXTENDED_READ &&
1711: FD_ISSET(c->efd, readset)) {
1712: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1713: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1714: c->self, len, c->efd);
1.93 markus 1715: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1716: return 1;
1717: if (len <= 0) {
1718: debug2("channel %d: closing read-efd %d",
1.45 markus 1719: c->self, c->efd);
1.132 markus 1720: channel_close_fd(&c->efd);
1.93 markus 1721: } else {
1.44 markus 1722: buffer_append(&c->extended, buf, len);
1.93 markus 1723: }
1.44 markus 1724: }
1725: }
1726: return 1;
1727: }
1.241 deraadt 1728:
1.259 stevesk 1729: /* ARGSUSED */
1.127 itojun 1730: static int
1.237 deraadt 1731: channel_handle_ctl(Channel *c, fd_set *readset, fd_set *writeset)
1.204 djm 1732: {
1733: char buf[16];
1734: int len;
1735:
1736: /* Monitor control fd to detect if the slave client exits */
1737: if (c->ctl_fd != -1 && FD_ISSET(c->ctl_fd, readset)) {
1738: len = read(c->ctl_fd, buf, sizeof(buf));
1739: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1740: return 1;
1741: if (len <= 0) {
1742: debug2("channel %d: ctl read<=0", c->self);
1743: if (c->type != SSH_CHANNEL_OPEN) {
1744: debug2("channel %d: not open", c->self);
1745: chan_mark_dead(c);
1746: return -1;
1747: } else {
1748: chan_read_failed(c);
1749: chan_write_failed(c);
1750: }
1751: return -1;
1752: } else
1753: fatal("%s: unexpected data on ctl fd", __func__);
1754: }
1755: return 1;
1756: }
1.241 deraadt 1757:
1.204 djm 1758: static int
1.93 markus 1759: channel_check_window(Channel *c)
1.44 markus 1760: {
1.104 markus 1761: if (c->type == SSH_CHANNEL_OPEN &&
1762: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1763: ((c->local_window_max - c->local_window >
1.269 markus 1764: c->local_maxpacket*3) ||
1765: c->local_window < c->local_window_max/2) &&
1.44 markus 1766: c->local_consumed > 0) {
1767: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1768: packet_put_int(c->remote_id);
1769: packet_put_int(c->local_consumed);
1770: packet_send();
1.70 markus 1771: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1772: c->self, c->local_window,
1773: c->local_consumed);
1774: c->local_window += c->local_consumed;
1775: c->local_consumed = 0;
1.1 deraadt 1776: }
1.41 markus 1777: return 1;
1.1 deraadt 1778: }
1779:
1.127 itojun 1780: static void
1.237 deraadt 1781: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1782: {
1783: channel_handle_rfd(c, readset, writeset);
1784: channel_handle_wfd(c, readset, writeset);
1.157 markus 1785: if (!compat20)
1.137 markus 1786: return;
1.44 markus 1787: channel_handle_efd(c, readset, writeset);
1.204 djm 1788: channel_handle_ctl(c, readset, writeset);
1.93 markus 1789: channel_check_window(c);
1.44 markus 1790: }
1791:
1.259 stevesk 1792: /* ARGSUSED */
1.127 itojun 1793: static void
1.237 deraadt 1794: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1795: {
1.41 markus 1796: int len;
1.180 deraadt 1797:
1.41 markus 1798: /* Send buffered output data to the socket. */
1799: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1800: len = write(c->sock, buffer_ptr(&c->output),
1801: buffer_len(&c->output));
1802: if (len <= 0)
1.158 markus 1803: buffer_clear(&c->output);
1.41 markus 1804: else
1805: buffer_consume(&c->output, len);
1806: }
1807: }
1.25 markus 1808:
1.127 itojun 1809: static void
1.44 markus 1810: channel_handler_init_20(void)
1811: {
1.157 markus 1812: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1813: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1814: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1815: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.51 markus 1816: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1817: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1818: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1819: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.44 markus 1820:
1.157 markus 1821: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1822: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1823: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.51 markus 1824: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1825: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1826: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1827: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.44 markus 1828: }
1829:
1.127 itojun 1830: static void
1.41 markus 1831: channel_handler_init_13(void)
1832: {
1833: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
1834: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
1835: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1836: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1837: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1838: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
1839: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 1840: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1841: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1842:
1.157 markus 1843: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 1844: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1845: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1846: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1847: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 1848: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1849: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1850: }
1.25 markus 1851:
1.127 itojun 1852: static void
1.41 markus 1853: channel_handler_init_15(void)
1854: {
1.157 markus 1855: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1856: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 1857: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1858: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1859: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1860: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1861: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 1862:
1.41 markus 1863: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1864: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1865: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 1866: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 1867: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1868: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 1869: }
1.27 markus 1870:
1.127 itojun 1871: static void
1.41 markus 1872: channel_handler_init(void)
1873: {
1874: int i;
1.180 deraadt 1875:
1.148 deraadt 1876: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 1877: channel_pre[i] = NULL;
1878: channel_post[i] = NULL;
1879: }
1.44 markus 1880: if (compat20)
1881: channel_handler_init_20();
1882: else if (compat13)
1.41 markus 1883: channel_handler_init_13();
1884: else
1885: channel_handler_init_15();
1886: }
1.25 markus 1887:
1.140 markus 1888: /* gc dead channels */
1889: static void
1890: channel_garbage_collect(Channel *c)
1891: {
1892: if (c == NULL)
1893: return;
1894: if (c->detach_user != NULL) {
1.225 djm 1895: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1896: return;
1.194 markus 1897: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1898: c->detach_user(c->self, NULL);
1899: /* if we still have a callback */
1900: if (c->detach_user != NULL)
1901: return;
1.194 markus 1902: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1903: }
1904: if (!chan_is_dead(c, 1))
1905: return;
1.194 markus 1906: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1907: channel_free(c);
1908: }
1909:
1.127 itojun 1910: static void
1.237 deraadt 1911: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset)
1.41 markus 1912: {
1913: static int did_init = 0;
1.299 markus 1914: u_int i, oalloc;
1.41 markus 1915: Channel *c;
1.25 markus 1916:
1.41 markus 1917: if (!did_init) {
1918: channel_handler_init();
1919: did_init = 1;
1920: }
1.299 markus 1921: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 1922: c = channels[i];
1923: if (c == NULL)
1.41 markus 1924: continue;
1.299 markus 1925: if (c->delayed) {
1926: if (ftab == channel_pre)
1927: c->delayed = 0;
1928: else
1929: continue;
1930: }
1.118 markus 1931: if (ftab[c->type] != NULL)
1932: (*ftab[c->type])(c, readset, writeset);
1.140 markus 1933: channel_garbage_collect(c);
1.1 deraadt 1934: }
1935: }
1936:
1.121 markus 1937: /*
1938: * Allocate/update select bitmasks and add any bits relevant to channels in
1939: * select bitmasks.
1940: */
1.49 markus 1941: void
1.100 markus 1942: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.209 avsm 1943: u_int *nallocp, int rekeying)
1.41 markus 1944: {
1.243 djm 1945: u_int n, sz, nfdset;
1.84 markus 1946:
1947: n = MAX(*maxfdp, channel_max_fd);
1948:
1.243 djm 1949: nfdset = howmany(n+1, NFDBITS);
1950: /* Explicitly test here, because xrealloc isn't always called */
1951: if (nfdset && SIZE_T_MAX / nfdset < sizeof(fd_mask))
1952: fatal("channel_prepare_select: max_fd (%d) is too large", n);
1953: sz = nfdset * sizeof(fd_mask);
1954:
1.132 markus 1955: /* perhaps check sz < nalloc/2 and shrink? */
1956: if (*readsetp == NULL || sz > *nallocp) {
1.243 djm 1957: *readsetp = xrealloc(*readsetp, nfdset, sizeof(fd_mask));
1958: *writesetp = xrealloc(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 1959: *nallocp = sz;
1.84 markus 1960: }
1.132 markus 1961: *maxfdp = n;
1.84 markus 1962: memset(*readsetp, 0, sz);
1963: memset(*writesetp, 0, sz);
1964:
1.100 markus 1965: if (!rekeying)
1966: channel_handler(channel_pre, *readsetp, *writesetp);
1.41 markus 1967: }
1968:
1.121 markus 1969: /*
1970: * After select, perform any appropriate operations for channels which have
1971: * events pending.
1972: */
1.49 markus 1973: void
1.237 deraadt 1974: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 1975: {
1976: channel_handler(channel_post, readset, writeset);
1977: }
1978:
1.121 markus 1979:
1.84 markus 1980: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 1981: void
1.142 itojun 1982: channel_output_poll(void)
1.1 deraadt 1983: {
1.41 markus 1984: Channel *c;
1.209 avsm 1985: u_int i, len;
1.1 deraadt 1986:
1.25 markus 1987: for (i = 0; i < channels_alloc; i++) {
1.113 markus 1988: c = channels[i];
1989: if (c == NULL)
1990: continue;
1.37 markus 1991:
1.121 markus 1992: /*
1993: * We are only interested in channels that can have buffered
1994: * incoming data.
1995: */
1.37 markus 1996: if (compat13) {
1.41 markus 1997: if (c->type != SSH_CHANNEL_OPEN &&
1998: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 1999: continue;
2000: } else {
1.41 markus 2001: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 2002: continue;
2003: }
1.46 markus 2004: if (compat20 &&
2005: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2006: /* XXX is this true? */
1.140 markus 2007: debug3("channel %d: will not send data after close", c->self);
1.44 markus 2008: continue;
2009: }
1.25 markus 2010:
2011: /* Get the amount of buffered data for this channel. */
1.93 markus 2012: if ((c->istate == CHAN_INPUT_OPEN ||
2013: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2014: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 2015: if (c->datagram) {
2016: if (len > 0) {
2017: u_char *data;
2018: u_int dlen;
2019:
2020: data = buffer_get_string(&c->input,
2021: &dlen);
2022: packet_start(SSH2_MSG_CHANNEL_DATA);
2023: packet_put_int(c->remote_id);
2024: packet_put_string(data, dlen);
2025: packet_send();
2026: c->remote_window -= dlen + 4;
2027: xfree(data);
2028: }
2029: continue;
2030: }
1.121 markus 2031: /*
2032: * Send some data for the other side over the secure
2033: * connection.
2034: */
1.44 markus 2035: if (compat20) {
2036: if (len > c->remote_window)
2037: len = c->remote_window;
2038: if (len > c->remote_maxpacket)
2039: len = c->remote_maxpacket;
1.25 markus 2040: } else {
1.44 markus 2041: if (packet_is_interactive()) {
2042: if (len > 1024)
2043: len = 512;
2044: } else {
2045: /* Keep the packets at reasonable size. */
2046: if (len > packet_get_maxsize()/2)
2047: len = packet_get_maxsize()/2;
2048: }
1.25 markus 2049: }
1.41 markus 2050: if (len > 0) {
1.44 markus 2051: packet_start(compat20 ?
2052: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2053: packet_put_int(c->remote_id);
2054: packet_put_string(buffer_ptr(&c->input), len);
2055: packet_send();
2056: buffer_consume(&c->input, len);
2057: c->remote_window -= len;
2058: }
2059: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2060: if (compat13)
2061: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2062: /*
2063: * input-buffer is empty and read-socket shutdown:
1.172 markus 2064: * tell peer, that we will not send more data: send IEOF.
2065: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2066: */
1.172 markus 2067: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2068: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2069: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2070: else
2071: chan_ibuf_empty(c);
1.25 markus 2072: }
1.44 markus 2073: /* Send extended data, i.e. stderr */
2074: if (compat20 &&
1.172 markus 2075: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2076: c->remote_window > 0 &&
2077: (len = buffer_len(&c->extended)) > 0 &&
2078: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2079: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2080: c->self, c->remote_window, buffer_len(&c->extended),
2081: c->extended_usage);
1.44 markus 2082: if (len > c->remote_window)
2083: len = c->remote_window;
2084: if (len > c->remote_maxpacket)
2085: len = c->remote_maxpacket;
2086: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2087: packet_put_int(c->remote_id);
2088: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2089: packet_put_string(buffer_ptr(&c->extended), len);
2090: packet_send();
2091: buffer_consume(&c->extended, len);
2092: c->remote_window -= len;
1.93 markus 2093: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2094: }
1.25 markus 2095: }
1.1 deraadt 2096: }
2097:
1.121 markus 2098:
2099: /* -- protocol input */
1.249 djm 2100:
2101: /* ARGSUSED */
1.49 markus 2102: void
1.154 markus 2103: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2104: {
1.37 markus 2105: int id;
1.25 markus 2106: char *data;
1.77 markus 2107: u_int data_len;
1.41 markus 2108: Channel *c;
1.25 markus 2109:
2110: /* Get the channel number and verify it. */
1.37 markus 2111: id = packet_get_int();
1.41 markus 2112: c = channel_lookup(id);
2113: if (c == NULL)
1.37 markus 2114: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2115:
2116: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2117: if (c->type != SSH_CHANNEL_OPEN &&
2118: c->type != SSH_CHANNEL_X11_OPEN)
1.37 markus 2119: return;
2120:
1.25 markus 2121: /* Get the data. */
1.274 markus 2122: data = packet_get_string_ptr(&data_len);
1.200 markus 2123:
2124: /*
2125: * Ignore data for protocol > 1.3 if output end is no longer open.
2126: * For protocol 2 the sending side is reducing its window as it sends
2127: * data, so we must 'fake' consumption of the data in order to ensure
2128: * that window updates are sent back. Otherwise the connection might
2129: * deadlock.
2130: */
2131: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2132: if (compat20) {
2133: c->local_window -= data_len;
2134: c->local_consumed += data_len;
2135: }
2136: return;
2137: }
1.41 markus 2138:
1.143 deraadt 2139: if (compat20) {
1.44 markus 2140: if (data_len > c->local_maxpacket) {
1.188 itojun 2141: logit("channel %d: rcvd big packet %d, maxpack %d",
1.44 markus 2142: c->self, data_len, c->local_maxpacket);
2143: }
2144: if (data_len > c->local_window) {
1.188 itojun 2145: logit("channel %d: rcvd too much data %d, win %d",
1.44 markus 2146: c->self, data_len, c->local_window);
2147: return;
2148: }
2149: c->local_window -= data_len;
2150: }
1.228 reyk 2151: if (c->datagram)
2152: buffer_put_string(&c->output, data, data_len);
2153: else
2154: buffer_append(&c->output, data, data_len);
1.274 markus 2155: packet_check_eom();
1.1 deraadt 2156: }
1.121 markus 2157:
1.249 djm 2158: /* ARGSUSED */
1.49 markus 2159: void
1.154 markus 2160: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2161: {
2162: int id;
2163: char *data;
1.177 markus 2164: u_int data_len, tcode;
1.44 markus 2165: Channel *c;
2166:
2167: /* Get the channel number and verify it. */
2168: id = packet_get_int();
2169: c = channel_lookup(id);
2170:
2171: if (c == NULL)
2172: packet_disconnect("Received extended_data for bad channel %d.", id);
2173: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2174: logit("channel %d: ext data for non open", id);
1.44 markus 2175: return;
1.172 markus 2176: }
2177: if (c->flags & CHAN_EOF_RCVD) {
2178: if (datafellows & SSH_BUG_EXTEOF)
2179: debug("channel %d: accepting ext data after eof", id);
2180: else
2181: packet_disconnect("Received extended_data after EOF "
2182: "on channel %d.", id);
1.44 markus 2183: }
2184: tcode = packet_get_int();
2185: if (c->efd == -1 ||
2186: c->extended_usage != CHAN_EXTENDED_WRITE ||
2187: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2188: logit("channel %d: bad ext data", c->self);
1.44 markus 2189: return;
2190: }
2191: data = packet_get_string(&data_len);
1.152 markus 2192: packet_check_eom();
1.44 markus 2193: if (data_len > c->local_window) {
1.188 itojun 2194: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2195: c->self, data_len, c->local_window);
2196: xfree(data);
2197: return;
2198: }
1.70 markus 2199: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2200: c->local_window -= data_len;
2201: buffer_append(&c->extended, data, data_len);
2202: xfree(data);
2203: }
2204:
1.249 djm 2205: /* ARGSUSED */
1.49 markus 2206: void
1.154 markus 2207: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2208: {
2209: int id;
2210: Channel *c;
2211:
2212: id = packet_get_int();
1.152 markus 2213: packet_check_eom();
1.41 markus 2214: c = channel_lookup(id);
2215: if (c == NULL)
2216: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2217: chan_rcvd_ieof(c);
1.133 markus 2218:
2219: /* XXX force input close */
1.156 markus 2220: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2221: debug("channel %d: FORCE input drain", c->self);
2222: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2223: if (buffer_len(&c->input) == 0)
2224: chan_ibuf_empty(c);
1.133 markus 2225: }
2226:
1.41 markus 2227: }
1.1 deraadt 2228:
1.249 djm 2229: /* ARGSUSED */
1.49 markus 2230: void
1.154 markus 2231: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2232: {
1.41 markus 2233: int id;
2234: Channel *c;
1.1 deraadt 2235:
1.41 markus 2236: id = packet_get_int();
1.152 markus 2237: packet_check_eom();
1.41 markus 2238: c = channel_lookup(id);
2239: if (c == NULL)
2240: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2241:
2242: /*
2243: * Send a confirmation that we have closed the channel and no more
2244: * data is coming for it.
2245: */
1.25 markus 2246: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2247: packet_put_int(c->remote_id);
1.25 markus 2248: packet_send();
2249:
1.27 markus 2250: /*
2251: * If the channel is in closed state, we have sent a close request,
2252: * and the other side will eventually respond with a confirmation.
2253: * Thus, we cannot free the channel here, because then there would be
2254: * no-one to receive the confirmation. The channel gets freed when
2255: * the confirmation arrives.
2256: */
1.41 markus 2257: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2258: /*
2259: * Not a closed channel - mark it as draining, which will
2260: * cause it to be freed later.
2261: */
1.158 markus 2262: buffer_clear(&c->input);
1.41 markus 2263: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2264: }
1.1 deraadt 2265: }
2266:
1.41 markus 2267: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2268: /* ARGSUSED */
1.49 markus 2269: void
1.154 markus 2270: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2271: {
2272: int id = packet_get_int();
2273: Channel *c = channel_lookup(id);
1.151 markus 2274:
1.152 markus 2275: packet_check_eom();
1.41 markus 2276: if (c == NULL)
2277: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2278: chan_rcvd_oclose(c);
2279: }
1.1 deraadt 2280:
1.249 djm 2281: /* ARGSUSED */
1.49 markus 2282: void
1.154 markus 2283: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2284: {
1.41 markus 2285: int id = packet_get_int();
2286: Channel *c = channel_lookup(id);
1.1 deraadt 2287:
1.152 markus 2288: packet_check_eom();
1.41 markus 2289: if (c == NULL)
2290: packet_disconnect("Received close confirmation for "
2291: "out-of-range channel %d.", id);
2292: if (c->type != SSH_CHANNEL_CLOSED)
2293: packet_disconnect("Received close confirmation for "
2294: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2295: channel_free(c);
1.1 deraadt 2296: }
2297:
1.249 djm 2298: /* ARGSUSED */
1.49 markus 2299: void
1.154 markus 2300: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2301: {
1.41 markus 2302: int id, remote_id;
2303: Channel *c;
1.1 deraadt 2304:
1.41 markus 2305: id = packet_get_int();
2306: c = channel_lookup(id);
1.25 markus 2307:
1.41 markus 2308: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2309: packet_disconnect("Received open confirmation for "
2310: "non-opening channel %d.", id);
2311: remote_id = packet_get_int();
1.27 markus 2312: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2313: c->remote_id = remote_id;
2314: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2315:
2316: if (compat20) {
2317: c->remote_window = packet_get_int();
2318: c->remote_maxpacket = packet_get_int();
1.275 djm 2319: if (c->open_confirm) {
1.70 markus 2320: debug2("callback start");
1.275 djm 2321: c->open_confirm(c->self, c->open_confirm_ctx);
1.70 markus 2322: debug2("callback done");
1.44 markus 2323: }
1.194 markus 2324: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2325: c->remote_window, c->remote_maxpacket);
2326: }
1.152 markus 2327: packet_check_eom();
1.1 deraadt 2328: }
2329:
1.127 itojun 2330: static char *
1.114 markus 2331: reason2txt(int reason)
2332: {
1.143 deraadt 2333: switch (reason) {
1.114 markus 2334: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2335: return "administratively prohibited";
2336: case SSH2_OPEN_CONNECT_FAILED:
2337: return "connect failed";
2338: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2339: return "unknown channel type";
2340: case SSH2_OPEN_RESOURCE_SHORTAGE:
2341: return "resource shortage";
2342: }
1.117 stevesk 2343: return "unknown reason";
1.114 markus 2344: }
2345:
1.249 djm 2346: /* ARGSUSED */
1.49 markus 2347: void
1.154 markus 2348: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2349: {
1.86 markus 2350: int id, reason;
2351: char *msg = NULL, *lang = NULL;
1.41 markus 2352: Channel *c;
2353:
2354: id = packet_get_int();
2355: c = channel_lookup(id);
1.25 markus 2356:
1.41 markus 2357: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2358: packet_disconnect("Received open failure for "
2359: "non-opening channel %d.", id);
1.44 markus 2360: if (compat20) {
1.86 markus 2361: reason = packet_get_int();
1.110 markus 2362: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2363: msg = packet_get_string(NULL);
2364: lang = packet_get_string(NULL);
2365: }
1.188 itojun 2366: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2367: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.86 markus 2368: if (msg != NULL)
2369: xfree(msg);
2370: if (lang != NULL)
2371: xfree(lang);
1.44 markus 2372: }
1.152 markus 2373: packet_check_eom();
1.291 djm 2374: /* Schedule the channel for cleanup/deletion. */
2375: chan_mark_dead(c);
1.44 markus 2376: }
2377:
1.249 djm 2378: /* ARGSUSED */
1.121 markus 2379: void
1.154 markus 2380: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2381: {
2382: Channel *c;
1.178 markus 2383: int id;
2384: u_int adjust;
1.121 markus 2385:
2386: if (!compat20)
2387: return;
2388:
2389: /* Get the channel number and verify it. */
2390: id = packet_get_int();
2391: c = channel_lookup(id);
1.1 deraadt 2392:
1.229 markus 2393: if (c == NULL) {
2394: logit("Received window adjust for non-open channel %d.", id);
1.121 markus 2395: return;
2396: }
2397: adjust = packet_get_int();
1.152 markus 2398: packet_check_eom();
1.178 markus 2399: debug2("channel %d: rcvd adjust %u", id, adjust);
1.121 markus 2400: c->remote_window += adjust;
2401: }
1.1 deraadt 2402:
1.249 djm 2403: /* ARGSUSED */
1.121 markus 2404: void
1.154 markus 2405: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2406: {
1.121 markus 2407: Channel *c = NULL;
2408: u_short host_port;
2409: char *host, *originator_string;
1.276 djm 2410: int remote_id;
1.121 markus 2411:
2412: remote_id = packet_get_int();
2413: host = packet_get_string(NULL);
2414: host_port = packet_get_int();
1.25 markus 2415:
1.121 markus 2416: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2417: originator_string = packet_get_string(NULL);
2418: } else {
2419: originator_string = xstrdup("unknown (remote did not supply name)");
2420: }
1.152 markus 2421: packet_check_eom();
1.276 djm 2422: c = channel_connect_to(host, host_port,
2423: "connected socket", originator_string);
1.190 markus 2424: xfree(originator_string);
1.276 djm 2425: xfree(host);
1.121 markus 2426: if (c == NULL) {
2427: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2428: packet_put_int(remote_id);
2429: packet_send();
1.276 djm 2430: } else
2431: c->remote_id = remote_id;
1.1 deraadt 2432: }
2433:
1.275 djm 2434: /* ARGSUSED */
2435: void
2436: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2437: {
2438: Channel *c;
2439: struct channel_confirm *cc;
1.289 markus 2440: int id;
1.275 djm 2441:
2442: /* Reset keepalive timeout */
1.296 andreas 2443: packet_set_alive_timeouts(0);
1.275 djm 2444:
1.289 markus 2445: id = packet_get_int();
1.275 djm 2446: packet_check_eom();
2447:
1.289 markus 2448: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2449:
1.289 markus 2450: if ((c = channel_lookup(id)) == NULL) {
2451: logit("channel_input_status_confirm: %d: unknown", id);
1.275 djm 2452: return;
2453: }
2454: ;
2455: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
2456: return;
2457: cc->cb(type, c, cc->ctx);
2458: TAILQ_REMOVE(&c->status_confirms, cc, entry);
2459: bzero(cc, sizeof(*cc));
2460: xfree(cc);
2461: }
1.121 markus 2462:
2463: /* -- tcp forwarding */
1.135 markus 2464:
2465: void
2466: channel_set_af(int af)
2467: {
2468: IPv4or6 = af;
2469: }
1.121 markus 2470:
1.160 markus 2471: static int
1.295 djm 2472: channel_setup_fwd_listener(int type, const char *listen_addr,
2473: u_short listen_port, int *allocated_listen_port,
1.160 markus 2474: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
1.25 markus 2475: {
1.113 markus 2476: Channel *c;
1.226 djm 2477: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2478: struct addrinfo hints, *ai, *aitop;
1.212 djm 2479: const char *host, *addr;
1.35 markus 2480: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2481: in_port_t *lport_p;
1.25 markus 2482:
1.160 markus 2483: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2484: listen_addr : host_to_connect;
1.212 djm 2485: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2486:
1.160 markus 2487: if (host == NULL) {
2488: error("No forward host name.");
1.218 markus 2489: return 0;
1.73 markus 2490: }
1.294 djm 2491: if (strlen(host) >= NI_MAXHOST) {
1.87 markus 2492: error("Forward host name too long.");
1.218 markus 2493: return 0;
1.87 markus 2494: }
1.25 markus 2495:
1.28 markus 2496: /*
1.212 djm 2497: * Determine whether or not a port forward listens to loopback,
1.213 deraadt 2498: * specified address or wildcard. On the client, a specified bind
2499: * address will always override gateway_ports. On the server, a
2500: * gateway_ports of 1 (``yes'') will override the client's
2501: * specification and force a wildcard bind, whereas a value of 2
2502: * (``clientspecified'') will bind to whatever address the client
1.212 djm 2503: * asked for.
2504: *
2505: * Special-case listen_addrs are:
2506: *
2507: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2508: * "" (empty string), "*" -> wildcard v4/v6
2509: * "localhost" -> loopback v4/v6
2510: */
2511: addr = NULL;
2512: if (listen_addr == NULL) {
2513: /* No address specified: default to gateway_ports setting */
2514: if (gateway_ports)
2515: wildcard = 1;
2516: } else if (gateway_ports || is_client) {
2517: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
1.272 djm 2518: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
1.212 djm 2519: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
2520: (!is_client && gateway_ports == 1))
2521: wildcard = 1;
2522: else if (strcmp(listen_addr, "localhost") != 0)
2523: addr = listen_addr;
2524: }
2525:
2526: debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
2527: type, wildcard, (addr == NULL) ? "NULL" : addr);
2528:
2529: /*
1.35 markus 2530: * getaddrinfo returns a loopback address if the hostname is
2531: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2532: */
1.35 markus 2533: memset(&hints, 0, sizeof(hints));
2534: hints.ai_family = IPv4or6;
1.212 djm 2535: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2536: hints.ai_socktype = SOCK_STREAM;
1.73 markus 2537: snprintf(strport, sizeof strport, "%d", listen_port);
1.212 djm 2538: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2539: if (addr == NULL) {
2540: /* This really shouldn't happen */
2541: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2542: ssh_gai_strerror(r));
1.212 djm 2543: } else {
1.218 markus 2544: error("channel_setup_fwd_listener: "
1.271 dtucker 2545: "getaddrinfo(%.64s): %s", addr,
2546: ssh_gai_strerror(r));
1.212 djm 2547: }
1.218 markus 2548: return 0;
1.212 djm 2549: }
1.295 djm 2550: if (allocated_listen_port != NULL)
2551: *allocated_listen_port = 0;
1.35 markus 2552: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2553: switch (ai->ai_family) {
2554: case AF_INET:
2555: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2556: sin_port;
2557: break;
2558: case AF_INET6:
2559: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2560: sin6_port;
2561: break;
2562: default:
1.35 markus 2563: continue;
1.295 djm 2564: }
2565: /*
2566: * If allocating a port for -R forwards, then use the
2567: * same port for all address families.
2568: */
2569: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2570: allocated_listen_port != NULL && *allocated_listen_port > 0)
2571: *lport_p = htons(*allocated_listen_port);
2572:
1.35 markus 2573: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2574: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.160 markus 2575: error("channel_setup_fwd_listener: getnameinfo failed");
1.35 markus 2576: continue;
2577: }
2578: /* Create a port to listen for the host. */
1.300 dtucker 2579: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2580: if (sock < 0) {
2581: /* this is no error since kernel may not support ipv6 */
2582: verbose("socket: %.100s", strerror(errno));
2583: continue;
2584: }
1.226 djm 2585:
2586: channel_set_reuseaddr(sock);
1.182 stevesk 2587:
1.295 djm 2588: debug("Local forwarding listening on %s port %s.",
2589: ntop, strport);
1.35 markus 2590:
2591: /* Bind the socket to the address. */
2592: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2593: /* address can be in use ipv6 address is already bound */
2594: verbose("bind: %.100s", strerror(errno));
2595: close(sock);
2596: continue;
2597: }
2598: /* Start listening for connections on the socket. */
1.199 markus 2599: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2600: error("listen: %.100s", strerror(errno));
2601: close(sock);
2602: continue;
2603: }
1.295 djm 2604:
2605: /*
2606: * listen_port == 0 requests a dynamically allocated port -
2607: * record what we got.
2608: */
2609: if (type == SSH_CHANNEL_RPORT_LISTENER && listen_port == 0 &&
2610: allocated_listen_port != NULL &&
2611: *allocated_listen_port == 0) {
2612: *allocated_listen_port = get_sock_port(sock, 1);
2613: debug("Allocated listen port %d",
2614: *allocated_listen_port);
2615: }
2616:
1.35 markus 2617: /* Allocate a channel number for the socket. */
1.121 markus 2618: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2619: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2620: 0, "port listener", 1);
1.293 djm 2621: c->path = xstrdup(host);
1.113 markus 2622: c->host_port = port_to_connect;
2623: c->listening_port = listen_port;
1.35 markus 2624: success = 1;
2625: }
2626: if (success == 0)
1.160 markus 2627: error("channel_setup_fwd_listener: cannot listen to port: %d",
1.87 markus 2628: listen_port);
1.35 markus 2629: freeaddrinfo(aitop);
1.87 markus 2630: return success;
1.25 markus 2631: }
1.1 deraadt 2632:
1.202 djm 2633: int
2634: channel_cancel_rport_listener(const char *host, u_short port)
2635: {
1.209 avsm 2636: u_int i;
2637: int found = 0;
1.202 djm 2638:
1.213 deraadt 2639: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2640: Channel *c = channels[i];
2641:
2642: if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
1.293 djm 2643: strcmp(c->path, host) == 0 && c->listening_port == port) {
1.210 djm 2644: debug2("%s: close channel %d", __func__, i);
1.202 djm 2645: channel_free(c);
2646: found = 1;
2647: }
2648: }
2649:
2650: return (found);
2651: }
2652:
1.160 markus 2653: /* protocol local port fwd, used by ssh (and sshd in v1) */
2654: int
1.212 djm 2655: channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
1.160 markus 2656: const char *host_to_connect, u_short port_to_connect, int gateway_ports)
2657: {
2658: return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
1.295 djm 2659: listen_host, listen_port, NULL, host_to_connect, port_to_connect,
1.212 djm 2660: gateway_ports);
1.160 markus 2661: }
2662:
2663: /* protocol v2 remote port fwd, used by sshd */
2664: int
2665: channel_setup_remote_fwd_listener(const char *listen_address,
1.295 djm 2666: u_short listen_port, int *allocated_listen_port, int gateway_ports)
1.160 markus 2667: {
2668: return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
1.295 djm 2669: listen_address, listen_port, allocated_listen_port,
2670: NULL, 0, gateway_ports);
1.160 markus 2671: }
2672:
1.27 markus 2673: /*
2674: * Initiate forwarding of connections to port "port" on remote host through
2675: * the secure channel to host:port from local side.
2676: */
1.1 deraadt 2677:
1.253 markus 2678: int
1.212 djm 2679: channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
1.73 markus 2680: const char *host_to_connect, u_short port_to_connect)
1.25 markus 2681: {
1.153 markus 2682: int type, success = 0;
1.73 markus 2683:
1.25 markus 2684: /* Record locally that connection to this host/port is permitted. */
2685: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2686: fatal("channel_request_remote_forwarding: too many forwards");
2687:
2688: /* Send the forward request to the remote side. */
1.44 markus 2689: if (compat20) {
1.212 djm 2690: const char *address_to_bind;
1.267 djm 2691: if (listen_host == NULL) {
2692: if (datafellows & SSH_BUG_RFWD_ADDR)
2693: address_to_bind = "127.0.0.1";
2694: else
2695: address_to_bind = "localhost";
2696: } else if (*listen_host == '\0' ||
2697: strcmp(listen_host, "*") == 0) {
2698: if (datafellows & SSH_BUG_RFWD_ADDR)
2699: address_to_bind = "0.0.0.0";
2700: else
2701: address_to_bind = "";
2702: } else
1.212 djm 2703: address_to_bind = listen_host;
2704:
1.44 markus 2705: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2706: packet_put_cstring("tcpip-forward");
1.173 markus 2707: packet_put_char(1); /* boolean: want reply */
1.44 markus 2708: packet_put_cstring(address_to_bind);
2709: packet_put_int(listen_port);
1.73 markus 2710: packet_send();
2711: packet_write_wait();
2712: /* Assume that server accepts the request */
2713: success = 1;
1.44 markus 2714: } else {
2715: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.50 markus 2716: packet_put_int(listen_port);
2717: packet_put_cstring(host_to_connect);
1.44 markus 2718: packet_put_int(port_to_connect);
2719: packet_send();
2720: packet_write_wait();
1.73 markus 2721:
2722: /* Wait for response from the remote side. */
1.153 markus 2723: type = packet_read();
1.73 markus 2724: switch (type) {
2725: case SSH_SMSG_SUCCESS:
2726: success = 1;
2727: break;
2728: case SSH_SMSG_FAILURE:
2729: break;
2730: default:
2731: /* Unknown packet */
2732: packet_disconnect("Protocol error for port forward request:"
2733: "received packet type %d.", type);
2734: }
2735: }
2736: if (success) {
2737: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
2738: permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
2739: permitted_opens[num_permitted_opens].listen_port = listen_port;
2740: num_permitted_opens++;
1.44 markus 2741: }
1.253 markus 2742: return (success ? 0 : -1);
1.1 deraadt 2743: }
2744:
1.27 markus 2745: /*
1.208 deraadt 2746: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 2747: * local side.
2748: */
2749: void
1.212 djm 2750: channel_request_rforward_cancel(const char *host, u_short port)
1.202 djm 2751: {
2752: int i;
2753:
2754: if (!compat20)
2755: return;
2756:
2757: for (i = 0; i < num_permitted_opens; i++) {
1.208 deraadt 2758: if (permitted_opens[i].host_to_connect != NULL &&
1.202 djm 2759: permitted_opens[i].listen_port == port)
2760: break;
2761: }
2762: if (i >= num_permitted_opens) {
2763: debug("%s: requested forward not found", __func__);
2764: return;
2765: }
2766: packet_start(SSH2_MSG_GLOBAL_REQUEST);
2767: packet_put_cstring("cancel-tcpip-forward");
2768: packet_put_char(0);
1.212 djm 2769: packet_put_cstring(host == NULL ? "" : host);
1.202 djm 2770: packet_put_int(port);
2771: packet_send();
2772:
2773: permitted_opens[i].listen_port = 0;
2774: permitted_opens[i].port_to_connect = 0;
1.227 stevesk 2775: xfree(permitted_opens[i].host_to_connect);
1.202 djm 2776: permitted_opens[i].host_to_connect = NULL;
2777: }
2778:
2779: /*
1.27 markus 2780: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
2781: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 2782: * message if there was an error).
1.27 markus 2783: */
1.253 markus 2784: int
1.56 markus 2785: channel_input_port_forward_request(int is_root, int gateway_ports)
1.1 deraadt 2786: {
1.31 markus 2787: u_short port, host_port;
1.253 markus 2788: int success = 0;
1.25 markus 2789: char *hostname;
1.1 deraadt 2790:
1.25 markus 2791: /* Get arguments from the packet. */
2792: port = packet_get_int();
2793: hostname = packet_get_string(NULL);
2794: host_port = packet_get_int();
2795:
1.27 markus 2796: /*
2797: * Check that an unprivileged user is not trying to forward a
2798: * privileged port.
2799: */
1.25 markus 2800: if (port < IPPORT_RESERVED && !is_root)
1.192 markus 2801: packet_disconnect(
2802: "Requested forwarding of port %d but user is not root.",
2803: port);
2804: if (host_port == 0)
2805: packet_disconnect("Dynamic forwarding denied.");
2806:
1.73 markus 2807: /* Initiate forwarding */
1.253 markus 2808: success = channel_setup_local_fwd_listener(NULL, port, hostname,
1.212 djm 2809: host_port, gateway_ports);
1.25 markus 2810:
2811: /* Free the argument string. */
2812: xfree(hostname);
1.253 markus 2813:
2814: return (success ? 0 : -1);
1.1 deraadt 2815: }
2816:
1.99 markus 2817: /*
2818: * Permits opening to any host/port if permitted_opens[] is empty. This is
2819: * usually called by the server, because the user could connect to any port
2820: * anyway, and the server has no way to know but to trust the client anyway.
2821: */
2822: void
1.142 itojun 2823: channel_permit_all_opens(void)
1.99 markus 2824: {
2825: if (num_permitted_opens == 0)
2826: all_opens_permitted = 1;
2827: }
2828:
1.101 markus 2829: void
1.99 markus 2830: channel_add_permitted_opens(char *host, int port)
2831: {
2832: if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1.253 markus 2833: fatal("channel_add_permitted_opens: too many forwards");
1.99 markus 2834: debug("allow port forwarding to host %s port %d", host, port);
2835:
2836: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
2837: permitted_opens[num_permitted_opens].port_to_connect = port;
2838: num_permitted_opens++;
2839:
2840: all_opens_permitted = 0;
2841: }
2842:
1.258 dtucker 2843: int
1.257 dtucker 2844: channel_add_adm_permitted_opens(char *host, int port)
2845: {
2846: if (num_adm_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
2847: fatal("channel_add_adm_permitted_opens: too many forwards");
1.258 dtucker 2848: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 2849:
2850: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
2851: = xstrdup(host);
2852: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.258 dtucker 2853: return ++num_adm_permitted_opens;
1.257 dtucker 2854: }
2855:
2856: void
1.99 markus 2857: channel_clear_permitted_opens(void)
2858: {
2859: int i;
2860:
2861: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 2862: if (permitted_opens[i].host_to_connect != NULL)
2863: xfree(permitted_opens[i].host_to_connect);
1.99 markus 2864: num_permitted_opens = 0;
1.257 dtucker 2865: }
2866:
2867: void
2868: channel_clear_adm_permitted_opens(void)
2869: {
2870: int i;
1.99 markus 2871:
1.257 dtucker 2872: for (i = 0; i < num_adm_permitted_opens; i++)
2873: if (permitted_adm_opens[i].host_to_connect != NULL)
2874: xfree(permitted_adm_opens[i].host_to_connect);
2875: num_adm_permitted_opens = 0;
1.278 dtucker 2876: }
2877:
2878: void
2879: channel_print_adm_permitted_opens(void)
2880: {
1.286 djm 2881: int i;
1.278 dtucker 2882:
1.290 stevesk 2883: printf("permitopen");
1.288 stevesk 2884: if (num_adm_permitted_opens == 0) {
1.290 stevesk 2885: printf(" any\n");
1.288 stevesk 2886: return;
2887: }
1.278 dtucker 2888: for (i = 0; i < num_adm_permitted_opens; i++)
2889: if (permitted_adm_opens[i].host_to_connect != NULL)
2890: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
2891: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 2892: printf("\n");
1.99 markus 2893: }
2894:
1.276 djm 2895: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 2896: static int
1.276 djm 2897: connect_next(struct channel_connect *cctx)
1.41 markus 2898: {
1.276 djm 2899: int sock, saved_errno;
1.41 markus 2900: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
2901:
1.276 djm 2902: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
2903: if (cctx->ai->ai_family != AF_INET &&
2904: cctx->ai->ai_family != AF_INET6)
1.41 markus 2905: continue;
1.276 djm 2906: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
2907: ntop, sizeof(ntop), strport, sizeof(strport),
2908: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
2909: error("connect_next: getnameinfo failed");
1.41 markus 2910: continue;
2911: }
1.300 dtucker 2912: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
2913: cctx->ai->ai_protocol)) == -1) {
1.276 djm 2914: if (cctx->ai->ai_next == NULL)
1.186 djm 2915: error("socket: %.100s", strerror(errno));
2916: else
2917: verbose("socket: %.100s", strerror(errno));
1.41 markus 2918: continue;
2919: }
1.205 djm 2920: if (set_nonblock(sock) == -1)
2921: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 2922: if (connect(sock, cctx->ai->ai_addr,
2923: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
2924: debug("connect_next: host %.100s ([%.100s]:%s): "
2925: "%.100s", cctx->host, ntop, strport,
1.41 markus 2926: strerror(errno));
1.276 djm 2927: saved_errno = errno;
1.41 markus 2928: close(sock);
1.276 djm 2929: errno = saved_errno;
1.89 stevesk 2930: continue; /* fail -- try next */
1.41 markus 2931: }
1.276 djm 2932: debug("connect_next: host %.100s ([%.100s]:%s) "
2933: "in progress, fd=%d", cctx->host, ntop, strport, sock);
2934: cctx->ai = cctx->ai->ai_next;
2935: set_nodelay(sock);
2936: return sock;
2937: }
2938: return -1;
2939: }
1.41 markus 2940:
1.276 djm 2941: static void
2942: channel_connect_ctx_free(struct channel_connect *cctx)
2943: {
2944: xfree(cctx->host);
2945: if (cctx->aitop)
2946: freeaddrinfo(cctx->aitop);
2947: bzero(cctx, sizeof(*cctx));
2948: cctx->host = NULL;
2949: cctx->ai = cctx->aitop = NULL;
2950: }
2951:
2952: /* Return CONNECTING channel to remote host, port */
2953: static Channel *
2954: connect_to(const char *host, u_short port, char *ctype, char *rname)
2955: {
2956: struct addrinfo hints;
2957: int gaierr;
2958: int sock = -1;
2959: char strport[NI_MAXSERV];
2960: struct channel_connect cctx;
2961: Channel *c;
2962:
1.284 djm 2963: memset(&cctx, 0, sizeof(cctx));
1.276 djm 2964: memset(&hints, 0, sizeof(hints));
2965: hints.ai_family = IPv4or6;
2966: hints.ai_socktype = SOCK_STREAM;
2967: snprintf(strport, sizeof strport, "%d", port);
2968: if ((gaierr = getaddrinfo(host, strport, &hints, &cctx.aitop)) != 0) {
2969: error("connect_to %.100s: unknown host (%s)", host,
2970: ssh_gai_strerror(gaierr));
2971: return NULL;
1.41 markus 2972: }
1.276 djm 2973:
2974: cctx.host = xstrdup(host);
2975: cctx.port = port;
2976: cctx.ai = cctx.aitop;
2977:
2978: if ((sock = connect_next(&cctx)) == -1) {
2979: error("connect to %.100s port %d failed: %s",
2980: host, port, strerror(errno));
2981: channel_connect_ctx_free(&cctx);
2982: return NULL;
1.41 markus 2983: }
1.276 djm 2984: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
2985: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
2986: c->connect_ctx = cctx;
2987: return c;
1.41 markus 2988: }
1.99 markus 2989:
1.276 djm 2990: Channel *
2991: channel_connect_by_listen_address(u_short listen_port, char *ctype, char *rname)
1.73 markus 2992: {
2993: int i;
1.99 markus 2994:
1.276 djm 2995: for (i = 0; i < num_permitted_opens; i++) {
1.202 djm 2996: if (permitted_opens[i].host_to_connect != NULL &&
1.276 djm 2997: permitted_opens[i].listen_port == listen_port) {
1.99 markus 2998: return connect_to(
1.73 markus 2999: permitted_opens[i].host_to_connect,
1.276 djm 3000: permitted_opens[i].port_to_connect, ctype, rname);
3001: }
3002: }
1.74 markus 3003: error("WARNING: Server requests forwarding for unknown listen_port %d",
3004: listen_port);
1.276 djm 3005: return NULL;
1.73 markus 3006: }
3007:
1.99 markus 3008: /* Check if connecting to that port is permitted and connect. */
1.276 djm 3009: Channel *
3010: channel_connect_to(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 3011: {
1.257 dtucker 3012: int i, permit, permit_adm = 1;
1.99 markus 3013:
3014: permit = all_opens_permitted;
3015: if (!permit) {
3016: for (i = 0; i < num_permitted_opens; i++)
1.202 djm 3017: if (permitted_opens[i].host_to_connect != NULL &&
3018: permitted_opens[i].port_to_connect == port &&
1.99 markus 3019: strcmp(permitted_opens[i].host_to_connect, host) == 0)
3020: permit = 1;
1.257 dtucker 3021: }
1.99 markus 3022:
1.257 dtucker 3023: if (num_adm_permitted_opens > 0) {
3024: permit_adm = 0;
3025: for (i = 0; i < num_adm_permitted_opens; i++)
3026: if (permitted_adm_opens[i].host_to_connect != NULL &&
3027: permitted_adm_opens[i].port_to_connect == port &&
3028: strcmp(permitted_adm_opens[i].host_to_connect, host)
3029: == 0)
3030: permit_adm = 1;
1.99 markus 3031: }
1.257 dtucker 3032:
3033: if (!permit || !permit_adm) {
1.188 itojun 3034: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3035: "but the request was denied.", host, port);
1.276 djm 3036: return NULL;
1.99 markus 3037: }
1.276 djm 3038: return connect_to(host, port, ctype, rname);
1.204 djm 3039: }
3040:
3041: void
3042: channel_send_window_changes(void)
3043: {
1.209 avsm 3044: u_int i;
1.204 djm 3045: struct winsize ws;
3046:
3047: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3048: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3049: channels[i]->type != SSH_CHANNEL_OPEN)
3050: continue;
3051: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3052: continue;
3053: channel_request_start(i, "window-change", 0);
1.238 deraadt 3054: packet_put_int((u_int)ws.ws_col);
3055: packet_put_int((u_int)ws.ws_row);
3056: packet_put_int((u_int)ws.ws_xpixel);
3057: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3058: packet_send();
3059: }
1.99 markus 3060: }
3061:
1.121 markus 3062: /* -- X11 forwarding */
1.1 deraadt 3063:
1.27 markus 3064: /*
3065: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3066: * Returns 0 and a suitable display number for the DISPLAY variable
3067: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3068: */
1.141 stevesk 3069: int
1.163 stevesk 3070: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3071: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3072: {
1.149 markus 3073: Channel *nc = NULL;
1.31 markus 3074: int display_number, sock;
3075: u_short port;
1.35 markus 3076: struct addrinfo hints, *ai, *aitop;
3077: char strport[NI_MAXSERV];
3078: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3079:
1.224 markus 3080: if (chanids == NULL)
3081: return -1;
3082:
1.33 markus 3083: for (display_number = x11_display_offset;
1.148 deraadt 3084: display_number < MAX_DISPLAYS;
3085: display_number++) {
1.25 markus 3086: port = 6000 + display_number;
1.35 markus 3087: memset(&hints, 0, sizeof(hints));
3088: hints.ai_family = IPv4or6;
1.163 stevesk 3089: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3090: hints.ai_socktype = SOCK_STREAM;
3091: snprintf(strport, sizeof strport, "%d", port);
3092: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3093: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3094: return -1;
1.25 markus 3095: }
1.35 markus 3096: for (ai = aitop; ai; ai = ai->ai_next) {
3097: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3098: continue;
1.300 dtucker 3099: sock = socket(ai->ai_family, ai->ai_socktype,
3100: ai->ai_protocol);
1.35 markus 3101: if (sock < 0) {
3102: error("socket: %.100s", strerror(errno));
1.203 markus 3103: freeaddrinfo(aitop);
1.141 stevesk 3104: return -1;
1.35 markus 3105: }
1.226 djm 3106: channel_set_reuseaddr(sock);
1.35 markus 3107: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3108: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3109: close(sock);
1.183 itojun 3110:
1.35 markus 3111: for (n = 0; n < num_socks; n++) {
3112: close(socks[n]);
3113: }
3114: num_socks = 0;
3115: break;
3116: }
3117: socks[num_socks++] = sock;
3118: if (num_socks == NUM_SOCKS)
3119: break;
1.25 markus 3120: }
1.83 stevesk 3121: freeaddrinfo(aitop);
1.35 markus 3122: if (num_socks > 0)
3123: break;
1.25 markus 3124: }
3125: if (display_number >= MAX_DISPLAYS) {
3126: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3127: return -1;
1.25 markus 3128: }
3129: /* Start listening for connections on the socket. */
1.35 markus 3130: for (n = 0; n < num_socks; n++) {
3131: sock = socks[n];
1.199 markus 3132: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3133: error("listen: %.100s", strerror(errno));
3134: close(sock);
1.141 stevesk 3135: return -1;
1.35 markus 3136: }
1.25 markus 3137: }
1.35 markus 3138:
3139: /* Allocate a channel for each socket. */
1.242 djm 3140: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3141: for (n = 0; n < num_socks; n++) {
3142: sock = socks[n];
1.149 markus 3143: nc = channel_new("x11 listener",
1.51 markus 3144: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3145: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3146: 0, "X11 inet listener", 1);
1.167 markus 3147: nc->single_connection = single_connection;
1.224 markus 3148: (*chanids)[n] = nc->self;
1.35 markus 3149: }
1.224 markus 3150: (*chanids)[n] = -1;
1.1 deraadt 3151:
1.141 stevesk 3152: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3153: *display_numberp = display_number;
3154: return (0);
1.1 deraadt 3155: }
3156:
1.127 itojun 3157: static int
1.77 markus 3158: connect_local_xsocket(u_int dnr)
1.1 deraadt 3159: {
1.25 markus 3160: int sock;
3161: struct sockaddr_un addr;
3162:
1.147 stevesk 3163: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3164: if (sock < 0)
3165: error("socket: %.100s", strerror(errno));
3166: memset(&addr, 0, sizeof(addr));
3167: addr.sun_family = AF_UNIX;
3168: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3169: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3170: return sock;
3171: close(sock);
1.25 markus 3172: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3173: return -1;
1.1 deraadt 3174: }
3175:
1.51 markus 3176: int
3177: x11_connect_display(void)
1.1 deraadt 3178: {
1.248 deraadt 3179: u_int display_number;
1.25 markus 3180: const char *display;
1.51 markus 3181: char buf[1024], *cp;
1.35 markus 3182: struct addrinfo hints, *ai, *aitop;
3183: char strport[NI_MAXSERV];
1.248 deraadt 3184: int gaierr, sock = 0;
1.25 markus 3185:
3186: /* Try to open a socket for the local X server. */
3187: display = getenv("DISPLAY");
3188: if (!display) {
3189: error("DISPLAY not set.");
1.51 markus 3190: return -1;
1.25 markus 3191: }
1.27 markus 3192: /*
3193: * Now we decode the value of the DISPLAY variable and make a
3194: * connection to the real X server.
3195: */
3196:
3197: /*
3198: * Check if it is a unix domain socket. Unix domain displays are in
3199: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3200: */
1.25 markus 3201: if (strncmp(display, "unix:", 5) == 0 ||
3202: display[0] == ':') {
3203: /* Connect to the unix domain socket. */
1.248 deraadt 3204: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3205: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3206: display);
1.51 markus 3207: return -1;
1.25 markus 3208: }
3209: /* Create a socket. */
3210: sock = connect_local_xsocket(display_number);
3211: if (sock < 0)
1.51 markus 3212: return -1;
1.25 markus 3213:
3214: /* OK, we now have a connection to the display. */
1.51 markus 3215: return sock;
1.25 markus 3216: }
1.27 markus 3217: /*
3218: * Connect to an inet socket. The DISPLAY value is supposedly
3219: * hostname:d[.s], where hostname may also be numeric IP address.
3220: */
1.145 stevesk 3221: strlcpy(buf, display, sizeof(buf));
1.25 markus 3222: cp = strchr(buf, ':');
3223: if (!cp) {
3224: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3225: return -1;
1.25 markus 3226: }
3227: *cp = 0;
1.27 markus 3228: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 3229: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 3230: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3231: display);
1.51 markus 3232: return -1;
1.25 markus 3233: }
1.35 markus 3234:
3235: /* Look up the host address */
3236: memset(&hints, 0, sizeof(hints));
3237: hints.ai_family = IPv4or6;
3238: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 3239: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 3240: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3241: error("%.100s: unknown host. (%s)", buf,
3242: ssh_gai_strerror(gaierr));
1.51 markus 3243: return -1;
1.25 markus 3244: }
1.35 markus 3245: for (ai = aitop; ai; ai = ai->ai_next) {
3246: /* Create a socket. */
1.300 dtucker 3247: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 3248: if (sock < 0) {
1.194 markus 3249: debug2("socket: %.100s", strerror(errno));
1.41 markus 3250: continue;
3251: }
3252: /* Connect it to the display. */
3253: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 3254: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 3255: 6000 + display_number, strerror(errno));
3256: close(sock);
3257: continue;
3258: }
3259: /* Success */
3260: break;
1.35 markus 3261: }
3262: freeaddrinfo(aitop);
3263: if (!ai) {
1.248 deraadt 3264: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 3265: strerror(errno));
1.51 markus 3266: return -1;
1.25 markus 3267: }
1.162 stevesk 3268: set_nodelay(sock);
1.51 markus 3269: return sock;
3270: }
3271:
3272: /*
3273: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
3274: * the remote channel number. We should do whatever we want, and respond
3275: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
3276: */
3277:
1.259 stevesk 3278: /* ARGSUSED */
1.51 markus 3279: void
1.154 markus 3280: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 3281: {
1.113 markus 3282: Channel *c = NULL;
3283: int remote_id, sock = 0;
1.51 markus 3284: char *remote_host;
1.25 markus 3285:
1.113 markus 3286: debug("Received X11 open request.");
1.51 markus 3287:
1.113 markus 3288: remote_id = packet_get_int();
1.121 markus 3289:
3290: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 3291: remote_host = packet_get_string(NULL);
1.51 markus 3292: } else {
3293: remote_host = xstrdup("unknown (remote did not supply name)");
3294: }
1.152 markus 3295: packet_check_eom();
1.25 markus 3296:
1.51 markus 3297: /* Obtain a connection to the real X display. */
3298: sock = x11_connect_display();
1.113 markus 3299: if (sock != -1) {
3300: /* Allocate a channel for this connection. */
3301: c = channel_new("connected x11 socket",
3302: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
3303: remote_host, 1);
1.167 markus 3304: c->remote_id = remote_id;
3305: c->force_drain = 1;
1.113 markus 3306: }
1.190 markus 3307: xfree(remote_host);
1.113 markus 3308: if (c == NULL) {
1.51 markus 3309: /* Send refusal to the remote host. */
3310: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 3311: packet_put_int(remote_id);
1.51 markus 3312: } else {
3313: /* Send a confirmation to the remote host. */
3314: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 3315: packet_put_int(remote_id);
3316: packet_put_int(c->self);
1.51 markus 3317: }
1.113 markus 3318: packet_send();
1.72 markus 3319: }
3320:
3321: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 3322: /* ARGSUSED */
1.72 markus 3323: void
1.154 markus 3324: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 3325: {
3326: int rchan = packet_get_int();
1.180 deraadt 3327:
1.143 deraadt 3328: switch (type) {
1.72 markus 3329: case SSH_SMSG_AGENT_OPEN:
3330: error("Warning: ssh server tried agent forwarding.");
3331: break;
3332: case SSH_SMSG_X11_OPEN:
3333: error("Warning: ssh server tried X11 forwarding.");
3334: break;
3335: default:
1.154 markus 3336: error("deny_input_open: type %d", type);
1.72 markus 3337: break;
3338: }
1.230 stevesk 3339: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 3340: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
3341: packet_put_int(rchan);
3342: packet_send();
1.1 deraadt 3343: }
3344:
1.27 markus 3345: /*
3346: * Requests forwarding of X11 connections, generates fake authentication
3347: * data, and enables authentication spoofing.
1.121 markus 3348: * This should be called in the client only.
1.27 markus 3349: */
1.49 markus 3350: void
1.215 djm 3351: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.51 markus 3352: const char *proto, const char *data)
1.1 deraadt 3353: {
1.77 markus 3354: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 3355: u_int i, value;
1.25 markus 3356: char *new_data;
3357: int screen_number;
3358: const char *cp;
1.207 avsm 3359: u_int32_t rnd = 0;
1.25 markus 3360:
1.220 markus 3361: if (x11_saved_display == NULL)
3362: x11_saved_display = xstrdup(disp);
3363: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 3364: error("x11_request_forwarding_with_spoofing: different "
3365: "$DISPLAY already forwarded");
3366: return;
3367: }
3368:
1.266 djm 3369: cp = strchr(disp, ':');
1.25 markus 3370: if (cp)
3371: cp = strchr(cp, '.');
3372: if (cp)
1.245 deraadt 3373: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 3374: else
3375: screen_number = 0;
3376:
1.219 djm 3377: if (x11_saved_proto == NULL) {
3378: /* Save protocol name. */
3379: x11_saved_proto = xstrdup(proto);
3380: /*
1.221 djm 3381: * Extract real authentication data and generate fake data
1.219 djm 3382: * of the same length.
3383: */
3384: x11_saved_data = xmalloc(data_len);
3385: x11_fake_data = xmalloc(data_len);
3386: for (i = 0; i < data_len; i++) {
3387: if (sscanf(data + 2 * i, "%2x", &value) != 1)
3388: fatal("x11_request_forwarding: bad "
3389: "authentication data: %.100s", data);
3390: if (i % 4 == 0)
3391: rnd = arc4random();
3392: x11_saved_data[i] = value;
3393: x11_fake_data[i] = rnd & 0xff;
3394: rnd >>= 8;
3395: }
3396: x11_saved_data_len = data_len;
3397: x11_fake_data_len = data_len;
1.25 markus 3398: }
3399:
3400: /* Convert the fake data into hex. */
1.219 djm 3401: new_data = tohex(x11_fake_data, data_len);
1.25 markus 3402:
3403: /* Send the request packet. */
1.51 markus 3404: if (compat20) {
3405: channel_request_start(client_session_id, "x11-req", 0);
3406: packet_put_char(0); /* XXX bool single connection */
3407: } else {
3408: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
3409: }
3410: packet_put_cstring(proto);
3411: packet_put_cstring(new_data);
1.25 markus 3412: packet_put_int(screen_number);
3413: packet_send();
3414: packet_write_wait();
3415: xfree(new_data);
1.1 deraadt 3416: }
3417:
1.121 markus 3418:
3419: /* -- agent forwarding */
3420:
1.1 deraadt 3421: /* Sends a message to the server to request authentication fd forwarding. */
3422:
1.49 markus 3423: void
1.142 itojun 3424: auth_request_forwarding(void)
1.1 deraadt 3425: {
1.25 markus 3426: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
3427: packet_send();
3428: packet_write_wait();
1.1 deraadt 3429: }
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