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8efc0c15 | 1 | /* |
5260325f | 2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
5260325f | 3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
4 | * All rights reserved | |
5260325f | 5 | * This file contains functions for generic socket connection forwarding. |
6 | * There is also code for initiating connection forwarding for X11 connections, | |
7 | * arbitrary tcp/ip connections, and the authentication agent connection. | |
6ae2364d | 8 | * |
bcbf86ec | 9 | * As far as I am concerned, the code I have written for this software |
10 | * can be used freely for any purpose. Any derived versions of this | |
11 | * software must be clearly marked as such, and if the derived work is | |
12 | * incompatible with the protocol description in the RFC file, it must be | |
13 | * called by a name other than "ssh" or "Secure Shell". | |
14 | * | |
15 | * | |
7e7327a1 | 16 | * SSH2 support added by Markus Friedl. |
bcbf86ec | 17 | * Copyright (c) 1999,2000 Markus Friedl. All rights reserved. |
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. | |
5260325f | 40 | */ |
8efc0c15 | 41 | |
42 | #include "includes.h" | |
28b9cb4d | 43 | RCSID("$OpenBSD: channels.c,v 1.104 2001/04/10 07:46:58 markus Exp $"); |
42f11eb2 | 44 | |
45 | #include <openssl/rsa.h> | |
46 | #include <openssl/dsa.h> | |
8efc0c15 | 47 | |
48 | #include "ssh.h" | |
42f11eb2 | 49 | #include "ssh1.h" |
50 | #include "ssh2.h" | |
8efc0c15 | 51 | #include "packet.h" |
52 | #include "xmalloc.h" | |
53 | #include "buffer.h" | |
0490e609 | 54 | #include "bufaux.h" |
8efc0c15 | 55 | #include "uidswap.h" |
42f11eb2 | 56 | #include "log.h" |
57 | #include "misc.h" | |
8efc0c15 | 58 | #include "channels.h" |
59 | #include "nchan.h" | |
60 | #include "compat.h" | |
42f11eb2 | 61 | #include "canohost.h" |
4c8722d9 | 62 | #include "key.h" |
63 | #include "authfd.h" | |
7e7327a1 | 64 | |
8efc0c15 | 65 | /* Maximum number of fake X11 displays to try. */ |
66 | #define MAX_DISPLAYS 1000 | |
67 | ||
68 | /* Max len of agent socket */ | |
69 | #define MAX_SOCKET_NAME 100 | |
70 | ||
aa3378df | 71 | /* |
72 | * Pointer to an array containing all allocated channels. The array is | |
73 | * dynamically extended as needed. | |
74 | */ | |
8efc0c15 | 75 | static Channel *channels = NULL; |
76 | ||
aa3378df | 77 | /* |
78 | * Size of the channel array. All slots of the array must always be | |
79 | * initialized (at least the type field); unused slots are marked with type | |
80 | * SSH_CHANNEL_FREE. | |
81 | */ | |
8efc0c15 | 82 | static int channels_alloc = 0; |
83 | ||
aa3378df | 84 | /* |
85 | * Maximum file descriptor value used in any of the channels. This is | |
86 | * updated in channel_allocate. | |
87 | */ | |
39929cdb | 88 | static int channel_max_fd = 0; |
8efc0c15 | 89 | |
90 | /* Name and directory of socket for authentication agent forwarding. */ | |
91 | static char *channel_forwarded_auth_socket_name = NULL; | |
5260325f | 92 | static char *channel_forwarded_auth_socket_dir = NULL; |
8efc0c15 | 93 | |
94 | /* Saved X11 authentication protocol name. */ | |
95 | char *x11_saved_proto = NULL; | |
96 | ||
97 | /* Saved X11 authentication data. This is the real data. */ | |
98 | char *x11_saved_data = NULL; | |
1e3b8b07 | 99 | u_int x11_saved_data_len = 0; |
8efc0c15 | 100 | |
aa3378df | 101 | /* |
102 | * Fake X11 authentication data. This is what the server will be sending us; | |
103 | * we should replace any occurrences of this by the real data. | |
104 | */ | |
8efc0c15 | 105 | char *x11_fake_data = NULL; |
1e3b8b07 | 106 | u_int x11_fake_data_len; |
8efc0c15 | 107 | |
aa3378df | 108 | /* |
109 | * Data structure for storing which hosts are permitted for forward requests. | |
110 | * The local sides of any remote forwards are stored in this array to prevent | |
111 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
112 | * network (which might be behind a firewall). | |
113 | */ | |
5260325f | 114 | typedef struct { |
7368a6c8 | 115 | char *host_to_connect; /* Connect to 'host'. */ |
116 | u_short port_to_connect; /* Connect to 'port'. */ | |
117 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 118 | } ForwardPermission; |
119 | ||
120 | /* List of all permitted host/port pairs to connect. */ | |
121 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
122 | /* Number of permitted host/port pairs in the array. */ | |
123 | static int num_permitted_opens = 0; | |
aa3378df | 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 | */ | |
8efc0c15 | 129 | static int all_opens_permitted = 0; |
130 | ||
131 | /* This is set to true if both sides support SSH_PROTOFLAG_HOST_IN_FWD_OPEN. */ | |
132 | static int have_hostname_in_open = 0; | |
133 | ||
42f11eb2 | 134 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
135 | extern int IPv4or6; | |
136 | ||
0490e609 | 137 | void port_open_helper(Channel *c, char *rtype); |
138 | ||
8efc0c15 | 139 | /* Sets specific protocol options. */ |
140 | ||
6ae2364d | 141 | void |
5260325f | 142 | channel_set_options(int hostname_in_open) |
8efc0c15 | 143 | { |
5260325f | 144 | have_hostname_in_open = hostname_in_open; |
8efc0c15 | 145 | } |
146 | ||
7368a6c8 | 147 | /* lookup channel by id */ |
148 | ||
149 | Channel * | |
150 | channel_lookup(int id) | |
151 | { | |
152 | Channel *c; | |
3e98362e | 153 | if (id < 0 || id > channels_alloc) { |
7368a6c8 | 154 | log("channel_lookup: %d: bad id", id); |
155 | return NULL; | |
156 | } | |
157 | c = &channels[id]; | |
158 | if (c->type == SSH_CHANNEL_FREE) { | |
159 | log("channel_lookup: %d: bad id: channel free", id); | |
160 | return NULL; | |
161 | } | |
162 | return c; | |
163 | } | |
164 | ||
aa3378df | 165 | /* |
1d1ffb87 | 166 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 167 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 168 | */ |
8efc0c15 | 169 | |
0fbe8c74 | 170 | void |
a22aff1f | 171 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
172 | int extusage, int nonblock) | |
8efc0c15 | 173 | { |
5260325f | 174 | /* Update the maximum file descriptor value. */ |
39929cdb | 175 | channel_max_fd = MAX(channel_max_fd, rfd); |
176 | channel_max_fd = MAX(channel_max_fd, wfd); | |
177 | channel_max_fd = MAX(channel_max_fd, efd); | |
178 | ||
aa3378df | 179 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 180 | |
0fbe8c74 | 181 | c->rfd = rfd; |
182 | c->wfd = wfd; | |
183 | c->sock = (rfd == wfd) ? rfd : -1; | |
184 | c->efd = efd; | |
185 | c->extended_usage = extusage; | |
a22aff1f | 186 | |
0ae4fe1d | 187 | /* XXX ugly hack: nonblock is only set by the server */ |
188 | if (nonblock && isatty(c->rfd)) { | |
94dfb550 | 189 | debug("channel %d: rfd %d isatty", c->self, c->rfd); |
0ae4fe1d | 190 | c->isatty = 1; |
191 | if (!isatty(c->wfd)) { | |
94dfb550 | 192 | error("channel %d: wfd %d is not a tty?", |
0ae4fe1d | 193 | c->self, c->wfd); |
194 | } | |
195 | } else { | |
196 | c->isatty = 0; | |
197 | } | |
198 | ||
a22aff1f | 199 | /* enable nonblocking mode */ |
200 | if (nonblock) { | |
201 | if (rfd != -1) | |
202 | set_nonblock(rfd); | |
203 | if (wfd != -1) | |
204 | set_nonblock(wfd); | |
205 | if (efd != -1) | |
206 | set_nonblock(efd); | |
207 | } | |
0fbe8c74 | 208 | } |
209 | ||
210 | /* | |
211 | * Allocate a new channel object and set its type and socket. This will cause | |
212 | * remote_name to be freed. | |
213 | */ | |
214 | ||
215 | int | |
216 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, | |
a22aff1f | 217 | int window, int maxpack, int extusage, char *remote_name, int nonblock) |
0fbe8c74 | 218 | { |
219 | int i, found; | |
220 | Channel *c; | |
5260325f | 221 | |
222 | /* Do initial allocation if this is the first call. */ | |
223 | if (channels_alloc == 0) { | |
7e7327a1 | 224 | chan_init(); |
5260325f | 225 | channels_alloc = 10; |
226 | channels = xmalloc(channels_alloc * sizeof(Channel)); | |
227 | for (i = 0; i < channels_alloc; i++) | |
228 | channels[i].type = SSH_CHANNEL_FREE; | |
aa3378df | 229 | /* |
230 | * Kludge: arrange a call to channel_stop_listening if we | |
231 | * terminate with fatal(). | |
232 | */ | |
5260325f | 233 | fatal_add_cleanup((void (*) (void *)) channel_stop_listening, NULL); |
234 | } | |
235 | /* Try to find a free slot where to put the new channel. */ | |
236 | for (found = -1, i = 0; i < channels_alloc; i++) | |
237 | if (channels[i].type == SSH_CHANNEL_FREE) { | |
238 | /* Found a free slot. */ | |
239 | found = i; | |
240 | break; | |
241 | } | |
242 | if (found == -1) { | |
aa3378df | 243 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 244 | found = channels_alloc; |
245 | channels_alloc += 10; | |
de273eef | 246 | debug2("channel: expanding %d", channels_alloc); |
5260325f | 247 | channels = xrealloc(channels, channels_alloc * sizeof(Channel)); |
248 | for (i = found; i < channels_alloc; i++) | |
249 | channels[i].type = SSH_CHANNEL_FREE; | |
250 | } | |
251 | /* Initialize and return new channel number. */ | |
252 | c = &channels[found]; | |
253 | buffer_init(&c->input); | |
254 | buffer_init(&c->output); | |
7368a6c8 | 255 | buffer_init(&c->extended); |
5260325f | 256 | chan_init_iostates(c); |
a22aff1f | 257 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
5260325f | 258 | c->self = found; |
259 | c->type = type; | |
7368a6c8 | 260 | c->ctype = ctype; |
0b242b12 | 261 | c->local_window = window; |
262 | c->local_window_max = window; | |
263 | c->local_consumed = 0; | |
264 | c->local_maxpacket = maxpack; | |
5260325f | 265 | c->remote_id = -1; |
266 | c->remote_name = remote_name; | |
7368a6c8 | 267 | c->remote_window = 0; |
268 | c->remote_maxpacket = 0; | |
269 | c->cb_fn = NULL; | |
270 | c->cb_arg = NULL; | |
271 | c->cb_event = 0; | |
272 | c->dettach_user = NULL; | |
2e73a022 | 273 | c->input_filter = NULL; |
5260325f | 274 | debug("channel %d: new [%s]", found, remote_name); |
275 | return found; | |
8efc0c15 | 276 | } |
0fbe8c74 | 277 | /* old interface XXX */ |
6ae2364d | 278 | int |
7368a6c8 | 279 | channel_allocate(int type, int sock, char *remote_name) |
280 | { | |
a22aff1f | 281 | return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name, 1); |
7368a6c8 | 282 | } |
8efc0c15 | 283 | |
0fbe8c74 | 284 | |
285 | /* Close all channel fd/socket. */ | |
286 | ||
287 | void | |
288 | channel_close_fds(Channel *c) | |
289 | { | |
290 | if (c->sock != -1) { | |
291 | close(c->sock); | |
292 | c->sock = -1; | |
293 | } | |
294 | if (c->rfd != -1) { | |
295 | close(c->rfd); | |
296 | c->rfd = -1; | |
297 | } | |
298 | if (c->wfd != -1) { | |
299 | close(c->wfd); | |
300 | c->wfd = -1; | |
301 | } | |
302 | if (c->efd != -1) { | |
303 | close(c->efd); | |
304 | c->efd = -1; | |
305 | } | |
306 | } | |
307 | ||
308 | /* Free the channel and close its fd/socket. */ | |
8efc0c15 | 309 | |
6ae2364d | 310 | void |
7368a6c8 | 311 | channel_free(int id) |
8efc0c15 | 312 | { |
7368a6c8 | 313 | Channel *c = channel_lookup(id); |
b148018f | 314 | char *s = channel_open_message(); |
315 | ||
7368a6c8 | 316 | if (c == NULL) |
317 | packet_disconnect("channel free: bad local channel %d", id); | |
b148018f | 318 | debug("channel_free: channel %d: status: %s", id, s); |
319 | xfree(s); | |
320 | ||
7e7327a1 | 321 | if (c->dettach_user != NULL) { |
322 | debug("channel_free: channel %d: dettaching channel user", id); | |
323 | c->dettach_user(c->self, NULL); | |
324 | } | |
0fbe8c74 | 325 | if (c->sock != -1) |
7368a6c8 | 326 | shutdown(c->sock, SHUT_RDWR); |
0fbe8c74 | 327 | channel_close_fds(c); |
7368a6c8 | 328 | buffer_free(&c->input); |
329 | buffer_free(&c->output); | |
330 | buffer_free(&c->extended); | |
331 | c->type = SSH_CHANNEL_FREE; | |
332 | if (c->remote_name) { | |
333 | xfree(c->remote_name); | |
334 | c->remote_name = NULL; | |
5260325f | 335 | } |
8efc0c15 | 336 | } |
337 | ||
aa3378df | 338 | /* |
7368a6c8 | 339 | * 'channel_pre*' are called just before select() to add any bits relevant to |
340 | * channels in the select bitmasks. | |
aa3378df | 341 | */ |
7368a6c8 | 342 | /* |
343 | * 'channel_post*': perform any appropriate operations for channels which | |
344 | * have events pending. | |
345 | */ | |
346 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
347 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
348 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 349 | |
7368a6c8 | 350 | void |
351 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
8efc0c15 | 352 | { |
7368a6c8 | 353 | FD_SET(c->sock, readset); |
354 | } | |
5260325f | 355 | |
97fb6912 | 356 | void |
357 | channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset) | |
358 | { | |
359 | debug3("channel %d: waiting for connection", c->self); | |
360 | FD_SET(c->sock, writeset); | |
361 | } | |
362 | ||
7368a6c8 | 363 | void |
364 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) | |
365 | { | |
366 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
367 | FD_SET(c->sock, readset); | |
368 | if (buffer_len(&c->output) > 0) | |
369 | FD_SET(c->sock, writeset); | |
370 | } | |
5260325f | 371 | |
7368a6c8 | 372 | void |
373 | channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset) | |
374 | { | |
375 | /* test whether sockets are 'alive' for read/write */ | |
376 | if (c->istate == CHAN_INPUT_OPEN) | |
377 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
378 | FD_SET(c->sock, readset); | |
379 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
380 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
381 | if (buffer_len(&c->output) > 0) { | |
382 | FD_SET(c->sock, writeset); | |
383 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
384 | chan_obuf_empty(c); | |
385 | } | |
386 | } | |
387 | } | |
5260325f | 388 | |
7e7327a1 | 389 | void |
390 | channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset) | |
391 | { | |
392 | if (c->istate == CHAN_INPUT_OPEN && | |
393 | c->remote_window > 0 && | |
394 | buffer_len(&c->input) < c->remote_window) | |
395 | FD_SET(c->rfd, readset); | |
396 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
397 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
398 | if (buffer_len(&c->output) > 0) { | |
399 | FD_SET(c->wfd, writeset); | |
400 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
401 | chan_obuf_empty(c); | |
402 | } | |
403 | } | |
404 | /** XXX check close conditions, too */ | |
405 | if (c->efd != -1) { | |
406 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
407 | buffer_len(&c->extended) > 0) | |
408 | FD_SET(c->efd, writeset); | |
409 | else if (c->extended_usage == CHAN_EXTENDED_READ && | |
410 | buffer_len(&c->extended) < c->remote_window) | |
411 | FD_SET(c->efd, readset); | |
412 | } | |
413 | } | |
414 | ||
7368a6c8 | 415 | void |
416 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) | |
417 | { | |
418 | if (buffer_len(&c->input) == 0) { | |
419 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
420 | packet_put_int(c->remote_id); | |
421 | packet_send(); | |
422 | c->type = SSH_CHANNEL_CLOSED; | |
423 | debug("Closing channel %d after input drain.", c->self); | |
424 | } | |
425 | } | |
5260325f | 426 | |
7368a6c8 | 427 | void |
428 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) | |
429 | { | |
430 | if (buffer_len(&c->output) == 0) | |
431 | channel_free(c->self); | |
6ae2364d | 432 | else |
7368a6c8 | 433 | FD_SET(c->sock, writeset); |
434 | } | |
5260325f | 435 | |
7368a6c8 | 436 | /* |
437 | * This is a special state for X11 authentication spoofing. An opened X11 | |
438 | * connection (when authentication spoofing is being done) remains in this | |
439 | * state until the first packet has been completely read. The authentication | |
440 | * data in that packet is then substituted by the real data if it matches the | |
441 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 442 | * XXX All this happens at the client side. |
7368a6c8 | 443 | */ |
444 | int | |
445 | x11_open_helper(Channel *c) | |
446 | { | |
1e3b8b07 | 447 | u_char *ucp; |
448 | u_int proto_len, data_len; | |
5260325f | 449 | |
7368a6c8 | 450 | /* Check if the fixed size part of the packet is in buffer. */ |
451 | if (buffer_len(&c->output) < 12) | |
452 | return 0; | |
453 | ||
454 | /* Parse the lengths of variable-length fields. */ | |
1e3b8b07 | 455 | ucp = (u_char *) buffer_ptr(&c->output); |
7368a6c8 | 456 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
457 | proto_len = 256 * ucp[6] + ucp[7]; | |
458 | data_len = 256 * ucp[8] + ucp[9]; | |
459 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
460 | proto_len = ucp[6] + 256 * ucp[7]; | |
461 | data_len = ucp[8] + 256 * ucp[9]; | |
462 | } else { | |
463 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
464 | ucp[0]); | |
465 | return -1; | |
466 | } | |
5260325f | 467 | |
7368a6c8 | 468 | /* Check if the whole packet is in buffer. */ |
469 | if (buffer_len(&c->output) < | |
470 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) | |
471 | return 0; | |
5260325f | 472 | |
7368a6c8 | 473 | /* Check if authentication protocol matches. */ |
474 | if (proto_len != strlen(x11_saved_proto) || | |
475 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
476 | debug("X11 connection uses different authentication protocol."); | |
477 | return -1; | |
478 | } | |
479 | /* Check if authentication data matches our fake data. */ | |
480 | if (data_len != x11_fake_data_len || | |
481 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
482 | x11_fake_data, x11_fake_data_len) != 0) { | |
483 | debug("X11 auth data does not match fake data."); | |
484 | return -1; | |
485 | } | |
486 | /* Check fake data length */ | |
487 | if (x11_fake_data_len != x11_saved_data_len) { | |
488 | error("X11 fake_data_len %d != saved_data_len %d", | |
489 | x11_fake_data_len, x11_saved_data_len); | |
490 | return -1; | |
491 | } | |
492 | /* | |
493 | * Received authentication protocol and data match | |
494 | * our fake data. Substitute the fake data with real | |
495 | * data. | |
496 | */ | |
497 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
498 | x11_saved_data, x11_saved_data_len); | |
499 | return 1; | |
500 | } | |
5260325f | 501 | |
7368a6c8 | 502 | void |
503 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) | |
504 | { | |
505 | int ret = x11_open_helper(c); | |
506 | if (ret == 1) { | |
507 | /* Start normal processing for the channel. */ | |
508 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 509 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 510 | } else if (ret == -1) { |
511 | /* | |
512 | * We have received an X11 connection that has bad | |
513 | * authentication information. | |
514 | */ | |
54b974dc | 515 | log("X11 connection rejected because of wrong authentication."); |
7368a6c8 | 516 | buffer_clear(&c->input); |
517 | buffer_clear(&c->output); | |
518 | close(c->sock); | |
519 | c->sock = -1; | |
520 | c->type = SSH_CHANNEL_CLOSED; | |
521 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
522 | packet_put_int(c->remote_id); | |
523 | packet_send(); | |
524 | } | |
525 | } | |
5260325f | 526 | |
7368a6c8 | 527 | void |
0b242b12 | 528 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 529 | { |
530 | int ret = x11_open_helper(c); | |
531 | if (ret == 1) { | |
532 | c->type = SSH_CHANNEL_OPEN; | |
d0c832f3 | 533 | if (compat20) |
534 | channel_pre_open_20(c, readset, writeset); | |
535 | else | |
536 | channel_pre_open_15(c, readset, writeset); | |
7368a6c8 | 537 | } else if (ret == -1) { |
538 | debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); | |
0b242b12 | 539 | chan_read_failed(c); /** force close? */ |
7368a6c8 | 540 | chan_write_failed(c); |
541 | debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); | |
542 | } | |
543 | } | |
5260325f | 544 | |
0490e609 | 545 | |
28b9cb4d | 546 | int |
547 | channel_decode_helper(Channel *c, int start, int lookfor) | |
548 | { | |
549 | u_char *p; | |
550 | int i, have; | |
551 | ||
552 | p = buffer_ptr(&c->input); | |
553 | have = buffer_len(&c->input); | |
554 | debug2("channel %d: decode_helper: start %d have %d lookfor %d", | |
555 | c->self, start, have, lookfor); | |
556 | if (have < start) | |
557 | return 0; | |
558 | for (i = start; i < have; i++) { | |
559 | if (p[i] == lookfor) { | |
560 | debug2("channel %d: decode_helper: matched at %d", | |
561 | c->self, i); | |
562 | if (lookfor == '\0' || | |
563 | (i+3 < have && | |
564 | p[i+1] == '\n' && | |
565 | p[i+2] == '\r' && | |
566 | p[i+3] == '\n')) | |
567 | return i; | |
568 | } | |
569 | if (i > 4096) { | |
570 | /* the peer is probably sending garbage */ | |
571 | debug("channel %d: decode_helper: too long", | |
572 | c->self); | |
573 | return -1; | |
574 | } | |
575 | } | |
576 | return 0; /* need more */ | |
577 | } | |
578 | ||
579 | /* try to decode a socks4 header */ | |
580 | int | |
581 | channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset) | |
0490e609 | 582 | { |
583 | u_char *p, *host; | |
28b9cb4d | 584 | int len, have, ret; |
585 | char username[256]; | |
0490e609 | 586 | struct { |
587 | u_int8_t version; | |
588 | u_int8_t command; | |
589 | u_int16_t dest_port; | |
28b9cb4d | 590 | struct in_addr dest_addr; |
0490e609 | 591 | } s4_req, s4_rsp; |
592 | ||
28b9cb4d | 593 | debug2("channel %d: decode socks4", c->self); |
594 | ret = channel_decode_helper(c, sizeof(s4_req), '\0'); | |
595 | if (ret <= 0) | |
596 | return ret; | |
0490e609 | 597 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
598 | buffer_get(&c->input, (char *)&s4_req.command, 1); | |
599 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); | |
28b9cb4d | 600 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
0490e609 | 601 | p = buffer_ptr(&c->input); |
602 | len = strlen(p); | |
603 | have = buffer_len(&c->input); | |
28b9cb4d | 604 | debug2("channel %d: pre_dynamic: user %s/%d", c->self, p, len); |
0490e609 | 605 | if (len > have) |
28b9cb4d | 606 | fatal("channel %d: decode socks4: len %d > have %d", |
0490e609 | 607 | c->self, len, have); |
608 | strlcpy(username, p, sizeof(username)); | |
609 | buffer_consume(&c->input, len); | |
610 | buffer_consume(&c->input, 1); /* trailing '\0' */ | |
611 | ||
28b9cb4d | 612 | host = inet_ntoa(s4_req.dest_addr); |
0490e609 | 613 | strlcpy(c->path, host, sizeof(c->path)); |
614 | c->host_port = ntohs(s4_req.dest_port); | |
615 | ||
28b9cb4d | 616 | debug("channel %d: dynamic request: " |
0490e609 | 617 | "socks%x://%s@%s:%u/command?%u", |
618 | c->self, s4_req.version, username, host, c->host_port, | |
619 | s4_req.command); | |
620 | ||
28b9cb4d | 621 | if (s4_req.command != 1) { |
622 | debug("channel %d: cannot handle: socks4 cn %d", | |
623 | c->self, s4_req.command); | |
624 | return -1; | |
0490e609 | 625 | } |
28b9cb4d | 626 | s4_rsp.version = 0; /* vn: 0 for reply */ |
627 | s4_rsp.command = 90; /* cd: req granted */ | |
0490e609 | 628 | s4_rsp.dest_port = 0; /* ignored */ |
28b9cb4d | 629 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
0490e609 | 630 | buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp)); |
28b9cb4d | 631 | return 1; |
0490e609 | 632 | } |
633 | ||
28b9cb4d | 634 | /* dynamic port forwarding */ |
635 | void | |
636 | channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset) | |
637 | { | |
638 | u_char *p; | |
639 | int have, ret; | |
640 | ||
641 | have = buffer_len(&c->input); | |
642 | ||
643 | debug2("channel %d: pre_dynamic: have %d", c->self, have); | |
644 | buffer_dump(&c->input); | |
645 | /* check if the fixed size part of the packet is in buffer. */ | |
646 | if (have < 4) { | |
647 | /* need more */ | |
648 | FD_SET(c->sock, readset); | |
649 | return; | |
650 | } | |
651 | /* try to guess the protocol */ | |
652 | p = buffer_ptr(&c->input); | |
653 | switch (p[0]) { | |
654 | case 0x04: | |
655 | ret = channel_decode_socks4(c, readset, writeset); | |
656 | break; | |
657 | #if 0 | |
658 | case 'C': | |
659 | ret = channel_decode_https(c, readset, writeset); | |
660 | break; | |
661 | case 0x05: | |
662 | ret = channel_decode_socks5(c, readset, writeset); | |
663 | break; | |
664 | #endif | |
665 | default: | |
666 | ret = -1; | |
667 | break; | |
668 | } | |
669 | if (ret < 0) { | |
670 | channel_free(c->self); | |
671 | } else if (ret == 0) { | |
672 | debug2("channel %d: pre_dynamic: need more", c->self); | |
673 | /* need more */ | |
674 | FD_SET(c->sock, readset); | |
675 | } else { | |
676 | /* switch to the next state */ | |
677 | c->type = SSH_CHANNEL_OPENING; | |
678 | port_open_helper(c, "direct-tcpip"); | |
679 | } | |
680 | } | |
0490e609 | 681 | |
7368a6c8 | 682 | /* This is our fake X11 server socket. */ |
683 | void | |
684 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
685 | { | |
686 | struct sockaddr addr; | |
687 | int newsock, newch; | |
688 | socklen_t addrlen; | |
865ac82e | 689 | char buf[16384], *remote_ipaddr; |
0b242b12 | 690 | int remote_port; |
7368a6c8 | 691 | |
692 | if (FD_ISSET(c->sock, readset)) { | |
693 | debug("X11 connection requested."); | |
694 | addrlen = sizeof(addr); | |
695 | newsock = accept(c->sock, &addr, &addrlen); | |
696 | if (newsock < 0) { | |
697 | error("accept: %.100s", strerror(errno)); | |
698 | return; | |
5260325f | 699 | } |
865ac82e | 700 | remote_ipaddr = get_peer_ipaddr(newsock); |
0b242b12 | 701 | remote_port = get_peer_port(newsock); |
7368a6c8 | 702 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
865ac82e | 703 | remote_ipaddr, remote_port); |
0b242b12 | 704 | |
705 | newch = channel_new("x11", | |
706 | SSH_CHANNEL_OPENING, newsock, newsock, -1, | |
707 | c->local_window_max, c->local_maxpacket, | |
a22aff1f | 708 | 0, xstrdup(buf), 1); |
0b242b12 | 709 | if (compat20) { |
710 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
711 | packet_put_cstring("x11"); | |
712 | packet_put_int(newch); | |
713 | packet_put_int(c->local_window_max); | |
714 | packet_put_int(c->local_maxpacket); | |
865ac82e | 715 | /* originator ipaddr and port */ |
716 | packet_put_cstring(remote_ipaddr); | |
d0c832f3 | 717 | if (datafellows & SSH_BUG_X11FWD) { |
718 | debug("ssh2 x11 bug compat mode"); | |
719 | } else { | |
720 | packet_put_int(remote_port); | |
721 | } | |
0b242b12 | 722 | packet_send(); |
723 | } else { | |
724 | packet_start(SSH_SMSG_X11_OPEN); | |
725 | packet_put_int(newch); | |
726 | if (have_hostname_in_open) | |
727 | packet_put_string(buf, strlen(buf)); | |
728 | packet_send(); | |
729 | } | |
865ac82e | 730 | xfree(remote_ipaddr); |
8efc0c15 | 731 | } |
8efc0c15 | 732 | } |
733 | ||
0490e609 | 734 | void |
735 | port_open_helper(Channel *c, char *rtype) | |
736 | { | |
737 | int direct; | |
738 | char buf[1024]; | |
739 | char *remote_ipaddr = get_peer_ipaddr(c->sock); | |
740 | u_short remote_port = get_peer_port(c->sock); | |
741 | ||
742 | direct = (strcmp(rtype, "direct-tcpip") == 0); | |
743 | ||
744 | snprintf(buf, sizeof buf, | |
745 | "%s: listening port %d for %.100s port %d, " | |
746 | "connect from %.200s port %d", | |
747 | rtype, c->listening_port, c->path, c->host_port, | |
748 | remote_ipaddr, remote_port); | |
749 | ||
750 | xfree(c->remote_name); | |
751 | c->remote_name = xstrdup(buf); | |
752 | ||
753 | if (compat20) { | |
754 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
755 | packet_put_cstring(rtype); | |
756 | packet_put_int(c->self); | |
757 | packet_put_int(c->local_window_max); | |
758 | packet_put_int(c->local_maxpacket); | |
759 | if (direct) { | |
760 | /* target host, port */ | |
761 | packet_put_cstring(c->path); | |
762 | packet_put_int(c->host_port); | |
763 | } else { | |
764 | /* listen address, port */ | |
765 | packet_put_cstring(c->path); | |
766 | packet_put_int(c->listening_port); | |
767 | } | |
768 | /* originator host and port */ | |
769 | packet_put_cstring(remote_ipaddr); | |
770 | packet_put_int(remote_port); | |
771 | packet_send(); | |
772 | } else { | |
773 | packet_start(SSH_MSG_PORT_OPEN); | |
774 | packet_put_int(c->self); | |
775 | packet_put_cstring(c->path); | |
776 | packet_put_int(c->host_port); | |
777 | if (have_hostname_in_open) | |
778 | packet_put_cstring(c->remote_name); | |
779 | packet_send(); | |
780 | } | |
781 | xfree(remote_ipaddr); | |
782 | } | |
783 | ||
aa3378df | 784 | /* |
7368a6c8 | 785 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 786 | */ |
7368a6c8 | 787 | void |
788 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
789 | { | |
0490e609 | 790 | Channel *nc; |
7368a6c8 | 791 | struct sockaddr addr; |
0490e609 | 792 | int newsock, newch, nextstate; |
7368a6c8 | 793 | socklen_t addrlen; |
0490e609 | 794 | char *rtype; |
fa08c86b | 795 | |
7368a6c8 | 796 | if (FD_ISSET(c->sock, readset)) { |
797 | debug("Connection to port %d forwarding " | |
798 | "to %.100s port %d requested.", | |
799 | c->listening_port, c->path, c->host_port); | |
0490e609 | 800 | |
801 | rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ? | |
802 | "forwarded-tcpip" : "direct-tcpip"; | |
803 | nextstate = (c->host_port == 0) ? SSH_CHANNEL_DYNAMIC : | |
804 | SSH_CHANNEL_OPENING; | |
805 | ||
7368a6c8 | 806 | addrlen = sizeof(addr); |
807 | newsock = accept(c->sock, &addr, &addrlen); | |
808 | if (newsock < 0) { | |
809 | error("accept: %.100s", strerror(errno)); | |
810 | return; | |
811 | } | |
fa08c86b | 812 | newch = channel_new(rtype, |
0490e609 | 813 | nextstate, newsock, newsock, -1, |
7368a6c8 | 814 | c->local_window_max, c->local_maxpacket, |
0490e609 | 815 | 0, xstrdup(rtype), 1); |
816 | ||
817 | nc = channel_lookup(newch); | |
818 | if (nc == NULL) { | |
819 | error("xxx: no new channel:"); | |
820 | return; | |
7368a6c8 | 821 | } |
0490e609 | 822 | nc->listening_port = c->listening_port; |
823 | nc->host_port = c->host_port; | |
824 | strlcpy(nc->path, c->path, sizeof(nc->path)); | |
825 | ||
826 | if (nextstate != SSH_CHANNEL_DYNAMIC) | |
827 | port_open_helper(nc, rtype); | |
7368a6c8 | 828 | } |
829 | } | |
8efc0c15 | 830 | |
7368a6c8 | 831 | /* |
832 | * This is the authentication agent socket listening for connections from | |
833 | * clients. | |
834 | */ | |
835 | void | |
836 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
8efc0c15 | 837 | { |
5260325f | 838 | struct sockaddr addr; |
7368a6c8 | 839 | int newsock, newch; |
48e671d5 | 840 | socklen_t addrlen; |
5260325f | 841 | |
7368a6c8 | 842 | if (FD_ISSET(c->sock, readset)) { |
843 | addrlen = sizeof(addr); | |
844 | newsock = accept(c->sock, &addr, &addrlen); | |
845 | if (newsock < 0) { | |
846 | error("accept from auth socket: %.100s", strerror(errno)); | |
847 | return; | |
848 | } | |
fa08c86b | 849 | newch = channel_new("accepted auth socket", |
850 | SSH_CHANNEL_OPENING, newsock, newsock, -1, | |
851 | c->local_window_max, c->local_maxpacket, | |
852 | 0, xstrdup("accepted auth socket"), 1); | |
853 | if (compat20) { | |
854 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
855 | packet_put_cstring("auth-agent@openssh.com"); | |
856 | packet_put_int(newch); | |
857 | packet_put_int(c->local_window_max); | |
858 | packet_put_int(c->local_maxpacket); | |
859 | } else { | |
860 | packet_start(SSH_SMSG_AGENT_OPEN); | |
861 | packet_put_int(newch); | |
862 | } | |
7368a6c8 | 863 | packet_send(); |
864 | } | |
865 | } | |
5260325f | 866 | |
97fb6912 | 867 | void |
868 | channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset) | |
869 | { | |
870 | if (FD_ISSET(c->sock, writeset)) { | |
871 | int err = 0; | |
872 | int sz = sizeof(err); | |
873 | c->type = SSH_CHANNEL_OPEN; | |
2b87da3b | 874 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, &sz) < 0) { |
97fb6912 | 875 | debug("getsockopt SO_ERROR failed"); |
876 | } else { | |
877 | if (err == 0) { | |
878 | debug("channel %d: connected)", c->self); | |
879 | } else { | |
880 | debug("channel %d: not connected: %s", | |
881 | c->self, strerror(err)); | |
882 | chan_read_failed(c); | |
883 | chan_write_failed(c); | |
884 | } | |
885 | } | |
886 | } | |
887 | } | |
888 | ||
7368a6c8 | 889 | int |
890 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) | |
891 | { | |
892 | char buf[16*1024]; | |
893 | int len; | |
894 | ||
895 | if (c->rfd != -1 && | |
896 | FD_ISSET(c->rfd, readset)) { | |
897 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 898 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
899 | return 1; | |
7368a6c8 | 900 | if (len <= 0) { |
0b242b12 | 901 | debug("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 902 | c->self, c->rfd, len); |
28b9cb4d | 903 | if (c->type != SSH_CHANNEL_OPEN) { |
904 | debug("channel %d: not open", c->self); | |
0490e609 | 905 | channel_free(c->self); |
906 | return -1; | |
28b9cb4d | 907 | } else if (compat13) { |
7368a6c8 | 908 | buffer_consume(&c->output, buffer_len(&c->output)); |
909 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
910 | debug("Channel %d status set to input draining.", c->self); | |
911 | } else { | |
912 | chan_read_failed(c); | |
5260325f | 913 | } |
7368a6c8 | 914 | return -1; |
915 | } | |
2e73a022 | 916 | if(c->input_filter != NULL) { |
917 | if (c->input_filter(c, buf, len) == -1) { | |
918 | debug("filter stops channel %d", c->self); | |
919 | chan_read_failed(c); | |
920 | } | |
921 | } else { | |
922 | buffer_append(&c->input, buf, len); | |
923 | } | |
7368a6c8 | 924 | } |
925 | return 1; | |
926 | } | |
927 | int | |
928 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) | |
929 | { | |
95ce5599 | 930 | struct termios tio; |
7368a6c8 | 931 | int len; |
932 | ||
933 | /* Send buffered output data to the socket. */ | |
934 | if (c->wfd != -1 && | |
935 | FD_ISSET(c->wfd, writeset) && | |
936 | buffer_len(&c->output) > 0) { | |
937 | len = write(c->wfd, buffer_ptr(&c->output), | |
0fbe8c74 | 938 | buffer_len(&c->output)); |
939 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
940 | return 1; | |
7368a6c8 | 941 | if (len <= 0) { |
28b9cb4d | 942 | if (c->type != SSH_CHANNEL_OPEN) { |
943 | debug("channel %d: not open", c->self); | |
944 | channel_free(c->self); | |
945 | return -1; | |
946 | } else if (compat13) { | |
7368a6c8 | 947 | buffer_consume(&c->output, buffer_len(&c->output)); |
948 | debug("Channel %d status set to input draining.", c->self); | |
949 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
950 | } else { | |
951 | chan_write_failed(c); | |
5260325f | 952 | } |
7368a6c8 | 953 | return -1; |
954 | } | |
0ae4fe1d | 955 | if (compat20 && c->isatty) { |
0ae4fe1d | 956 | if (tcgetattr(c->wfd, &tio) == 0 && |
957 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { | |
958 | /* | |
959 | * Simulate echo to reduce the impact of | |
355724fc | 960 | * traffic analysis. We need to match the |
95ce5599 | 961 | * size of a SSH2_MSG_CHANNEL_DATA message |
962 | * (4 byte channel id + data) | |
0ae4fe1d | 963 | */ |
95ce5599 | 964 | packet_send_ignore(4 + len); |
0ae4fe1d | 965 | packet_send(); |
0ae4fe1d | 966 | } |
967 | } | |
7368a6c8 | 968 | buffer_consume(&c->output, len); |
7e7327a1 | 969 | if (compat20 && len > 0) { |
970 | c->local_consumed += len; | |
971 | } | |
972 | } | |
973 | return 1; | |
974 | } | |
975 | int | |
976 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) | |
977 | { | |
978 | char buf[16*1024]; | |
979 | int len; | |
980 | ||
8ce64345 | 981 | /** XXX handle drain efd, too */ |
7e7327a1 | 982 | if (c->efd != -1) { |
983 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
984 | FD_ISSET(c->efd, writeset) && | |
985 | buffer_len(&c->extended) > 0) { | |
986 | len = write(c->efd, buffer_ptr(&c->extended), | |
987 | buffer_len(&c->extended)); | |
de273eef | 988 | debug2("channel %d: written %d to efd %d", |
7e7327a1 | 989 | c->self, len, c->efd); |
ee55dacf | 990 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
991 | return 1; | |
992 | if (len <= 0) { | |
993 | debug2("channel %d: closing write-efd %d", | |
994 | c->self, c->efd); | |
995 | close(c->efd); | |
996 | c->efd = -1; | |
997 | } else { | |
7e7327a1 | 998 | buffer_consume(&c->extended, len); |
999 | c->local_consumed += len; | |
1000 | } | |
1001 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
1002 | FD_ISSET(c->efd, readset)) { | |
1003 | len = read(c->efd, buf, sizeof(buf)); | |
de273eef | 1004 | debug2("channel %d: read %d from efd %d", |
7e7327a1 | 1005 | c->self, len, c->efd); |
ee55dacf | 1006 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
1007 | return 1; | |
1008 | if (len <= 0) { | |
1009 | debug2("channel %d: closing read-efd %d", | |
8ce64345 | 1010 | c->self, c->efd); |
1011 | close(c->efd); | |
1012 | c->efd = -1; | |
ee55dacf | 1013 | } else { |
7e7327a1 | 1014 | buffer_append(&c->extended, buf, len); |
ee55dacf | 1015 | } |
7e7327a1 | 1016 | } |
1017 | } | |
1018 | return 1; | |
1019 | } | |
1020 | int | |
ee55dacf | 1021 | channel_check_window(Channel *c) |
7e7327a1 | 1022 | { |
28b9cb4d | 1023 | if (c->type == SSH_CHANNEL_OPEN && |
1024 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && | |
7e7327a1 | 1025 | c->local_window < c->local_window_max/2 && |
1026 | c->local_consumed > 0) { | |
1027 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
1028 | packet_put_int(c->remote_id); | |
1029 | packet_put_int(c->local_consumed); | |
1030 | packet_send(); | |
de273eef | 1031 | debug2("channel %d: window %d sent adjust %d", |
7e7327a1 | 1032 | c->self, c->local_window, |
1033 | c->local_consumed); | |
1034 | c->local_window += c->local_consumed; | |
1035 | c->local_consumed = 0; | |
7368a6c8 | 1036 | } |
1037 | return 1; | |
1038 | } | |
5260325f | 1039 | |
7368a6c8 | 1040 | void |
1041 | channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset) | |
1042 | { | |
1043 | channel_handle_rfd(c, readset, writeset); | |
1044 | channel_handle_wfd(c, readset, writeset); | |
1045 | } | |
aa3378df | 1046 | |
7e7327a1 | 1047 | void |
1048 | channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset) | |
1049 | { | |
1050 | channel_handle_rfd(c, readset, writeset); | |
1051 | channel_handle_wfd(c, readset, writeset); | |
1052 | channel_handle_efd(c, readset, writeset); | |
ee55dacf | 1053 | |
1054 | channel_check_window(c); | |
7e7327a1 | 1055 | } |
1056 | ||
7368a6c8 | 1057 | void |
1058 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) | |
1059 | { | |
1060 | int len; | |
1061 | /* Send buffered output data to the socket. */ | |
1062 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
1063 | len = write(c->sock, buffer_ptr(&c->output), | |
1064 | buffer_len(&c->output)); | |
1065 | if (len <= 0) | |
1066 | buffer_consume(&c->output, buffer_len(&c->output)); | |
1067 | else | |
1068 | buffer_consume(&c->output, len); | |
1069 | } | |
1070 | } | |
5260325f | 1071 | |
7e7327a1 | 1072 | void |
1073 | channel_handler_init_20(void) | |
1074 | { | |
1075 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20; | |
0b242b12 | 1076 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 1077 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
fa08c86b | 1078 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 1079 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
fa08c86b | 1080 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
97fb6912 | 1081 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1082 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7e7327a1 | 1083 | |
1084 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2; | |
1085 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
fa08c86b | 1086 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
0b242b12 | 1087 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
fa08c86b | 1088 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
97fb6912 | 1089 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1090 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2; |
7e7327a1 | 1091 | } |
1092 | ||
7368a6c8 | 1093 | void |
1094 | channel_handler_init_13(void) | |
1095 | { | |
1096 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
1097 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
1098 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
1099 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1100 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
1101 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
1102 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
97fb6912 | 1103 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1104 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1105 | |
1106 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
1107 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1108 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1109 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1110 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
97fb6912 | 1111 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1112 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1113 | } |
5260325f | 1114 | |
7368a6c8 | 1115 | void |
1116 | channel_handler_init_15(void) | |
1117 | { | |
1118 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15; | |
0b242b12 | 1119 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 1120 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
1121 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
1122 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
97fb6912 | 1123 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
0490e609 | 1124 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
7368a6c8 | 1125 | |
1126 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
1127 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
1128 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
1129 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
97fb6912 | 1130 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
28b9cb4d | 1131 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1; |
7368a6c8 | 1132 | } |
1133 | ||
1134 | void | |
1135 | channel_handler_init(void) | |
1136 | { | |
1137 | int i; | |
1138 | for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { | |
1139 | channel_pre[i] = NULL; | |
1140 | channel_post[i] = NULL; | |
1141 | } | |
7e7327a1 | 1142 | if (compat20) |
1143 | channel_handler_init_20(); | |
1144 | else if (compat13) | |
7368a6c8 | 1145 | channel_handler_init_13(); |
1146 | else | |
1147 | channel_handler_init_15(); | |
1148 | } | |
1149 | ||
6ae2364d | 1150 | void |
7368a6c8 | 1151 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
1152 | { | |
1153 | static int did_init = 0; | |
1154 | int i; | |
1155 | Channel *c; | |
1156 | ||
1157 | if (!did_init) { | |
1158 | channel_handler_init(); | |
1159 | did_init = 1; | |
1160 | } | |
1161 | for (i = 0; i < channels_alloc; i++) { | |
1162 | c = &channels[i]; | |
1163 | if (c->type == SSH_CHANNEL_FREE) | |
5260325f | 1164 | continue; |
7368a6c8 | 1165 | if (ftab[c->type] == NULL) |
1166 | continue; | |
1167 | (*ftab[c->type])(c, readset, writeset); | |
ee55dacf | 1168 | if (chan_is_dead(c)) { |
1169 | /* | |
1170 | * we have to remove the fd's from the select mask | |
1171 | * before the channels are free'd and the fd's are | |
1172 | * closed | |
1173 | */ | |
1174 | if (c->wfd != -1) | |
1175 | FD_CLR(c->wfd, writeset); | |
1176 | if (c->rfd != -1) | |
1177 | FD_CLR(c->rfd, readset); | |
1178 | if (c->efd != -1) { | |
1179 | if (c->extended_usage == CHAN_EXTENDED_READ) | |
1180 | FD_CLR(c->efd, readset); | |
1181 | if (c->extended_usage == CHAN_EXTENDED_WRITE) | |
1182 | FD_CLR(c->efd, writeset); | |
1183 | } | |
1184 | channel_free(c->self); | |
1185 | } | |
8efc0c15 | 1186 | } |
8efc0c15 | 1187 | } |
1188 | ||
6ae2364d | 1189 | void |
c422989b | 1190 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
1191 | int rekeying) | |
7368a6c8 | 1192 | { |
39929cdb | 1193 | int n; |
1194 | u_int sz; | |
1195 | ||
1196 | n = MAX(*maxfdp, channel_max_fd); | |
1197 | ||
1198 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
1199 | if (*readsetp == NULL || n > *maxfdp) { | |
1200 | if (*readsetp) | |
1201 | xfree(*readsetp); | |
1202 | if (*writesetp) | |
1203 | xfree(*writesetp); | |
1204 | *readsetp = xmalloc(sz); | |
1205 | *writesetp = xmalloc(sz); | |
1206 | *maxfdp = n; | |
1207 | } | |
1208 | memset(*readsetp, 0, sz); | |
1209 | memset(*writesetp, 0, sz); | |
1210 | ||
c422989b | 1211 | if (!rekeying) |
1212 | channel_handler(channel_pre, *readsetp, *writesetp); | |
7368a6c8 | 1213 | } |
1214 | ||
6ae2364d | 1215 | void |
7368a6c8 | 1216 | channel_after_select(fd_set * readset, fd_set * writeset) |
1217 | { | |
1218 | channel_handler(channel_post, readset, writeset); | |
1219 | } | |
1220 | ||
39929cdb | 1221 | /* If there is data to send to the connection, enqueue some of it now. */ |
8efc0c15 | 1222 | |
6ae2364d | 1223 | void |
5260325f | 1224 | channel_output_poll() |
8efc0c15 | 1225 | { |
5260325f | 1226 | int len, i; |
7368a6c8 | 1227 | Channel *c; |
5260325f | 1228 | |
1229 | for (i = 0; i < channels_alloc; i++) { | |
7368a6c8 | 1230 | c = &channels[i]; |
48e671d5 | 1231 | |
aa3378df | 1232 | /* We are only interested in channels that can have buffered incoming data. */ |
48e671d5 | 1233 | if (compat13) { |
7368a6c8 | 1234 | if (c->type != SSH_CHANNEL_OPEN && |
1235 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 1236 | continue; |
1237 | } else { | |
7368a6c8 | 1238 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 1239 | continue; |
48e671d5 | 1240 | } |
e78a59f5 | 1241 | if (compat20 && |
1242 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
ee55dacf | 1243 | /* XXX is this true? */ |
61f8a1d1 | 1244 | debug2("channel %d: no data after CLOSE", c->self); |
7e7327a1 | 1245 | continue; |
1246 | } | |
5260325f | 1247 | |
1248 | /* Get the amount of buffered data for this channel. */ | |
ee55dacf | 1249 | if ((c->istate == CHAN_INPUT_OPEN || |
1250 | c->istate == CHAN_INPUT_WAIT_DRAIN) && | |
1251 | (len = buffer_len(&c->input)) > 0) { | |
aa3378df | 1252 | /* Send some data for the other side over the secure connection. */ |
7e7327a1 | 1253 | if (compat20) { |
1254 | if (len > c->remote_window) | |
1255 | len = c->remote_window; | |
1256 | if (len > c->remote_maxpacket) | |
1257 | len = c->remote_maxpacket; | |
5260325f | 1258 | } else { |
7e7327a1 | 1259 | if (packet_is_interactive()) { |
1260 | if (len > 1024) | |
1261 | len = 512; | |
1262 | } else { | |
1263 | /* Keep the packets at reasonable size. */ | |
1264 | if (len > packet_get_maxsize()/2) | |
1265 | len = packet_get_maxsize()/2; | |
1266 | } | |
5260325f | 1267 | } |
7368a6c8 | 1268 | if (len > 0) { |
7e7327a1 | 1269 | packet_start(compat20 ? |
1270 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 1271 | packet_put_int(c->remote_id); |
1272 | packet_put_string(buffer_ptr(&c->input), len); | |
1273 | packet_send(); | |
1274 | buffer_consume(&c->input, len); | |
1275 | c->remote_window -= len; | |
7368a6c8 | 1276 | } |
1277 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 1278 | if (compat13) |
1279 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 1280 | /* |
1281 | * input-buffer is empty and read-socket shutdown: | |
1282 | * tell peer, that we will not send more data: send IEOF | |
1283 | */ | |
7368a6c8 | 1284 | chan_ibuf_empty(c); |
5260325f | 1285 | } |
7e7327a1 | 1286 | /* Send extended data, i.e. stderr */ |
1287 | if (compat20 && | |
1288 | c->remote_window > 0 && | |
1289 | (len = buffer_len(&c->extended)) > 0 && | |
1290 | c->extended_usage == CHAN_EXTENDED_READ) { | |
ee55dacf | 1291 | debug2("channel %d: rwin %d elen %d euse %d", |
1292 | c->self, c->remote_window, buffer_len(&c->extended), | |
1293 | c->extended_usage); | |
7e7327a1 | 1294 | if (len > c->remote_window) |
1295 | len = c->remote_window; | |
1296 | if (len > c->remote_maxpacket) | |
1297 | len = c->remote_maxpacket; | |
1298 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
1299 | packet_put_int(c->remote_id); | |
1300 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
1301 | packet_put_string(buffer_ptr(&c->extended), len); | |
1302 | packet_send(); | |
1303 | buffer_consume(&c->extended, len); | |
1304 | c->remote_window -= len; | |
ee55dacf | 1305 | debug2("channel %d: sent ext data %d", c->self, len); |
7e7327a1 | 1306 | } |
8efc0c15 | 1307 | } |
8efc0c15 | 1308 | } |
1309 | ||
aa3378df | 1310 | /* |
1311 | * This is called when a packet of type CHANNEL_DATA has just been received. | |
1312 | * The message type has already been consumed, but channel number and data is | |
1313 | * still there. | |
1314 | */ | |
8efc0c15 | 1315 | |
6ae2364d | 1316 | void |
188adeb2 | 1317 | channel_input_data(int type, int plen, void *ctxt) |
8efc0c15 | 1318 | { |
48e671d5 | 1319 | int id; |
5260325f | 1320 | char *data; |
1e3b8b07 | 1321 | u_int data_len; |
7368a6c8 | 1322 | Channel *c; |
5260325f | 1323 | |
1324 | /* Get the channel number and verify it. */ | |
48e671d5 | 1325 | id = packet_get_int(); |
7368a6c8 | 1326 | c = channel_lookup(id); |
1327 | if (c == NULL) | |
48e671d5 | 1328 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 1329 | |
1330 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 1331 | if (c->type != SSH_CHANNEL_OPEN && |
1332 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 1333 | return; |
1334 | ||
1335 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 1336 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 1337 | return; |
1338 | ||
1339 | /* Get the data. */ | |
1340 | data = packet_get_string(&data_len); | |
6ae2364d | 1341 | packet_done(); |
7368a6c8 | 1342 | |
7e7327a1 | 1343 | if (compat20){ |
1344 | if (data_len > c->local_maxpacket) { | |
1345 | log("channel %d: rcvd big packet %d, maxpack %d", | |
1346 | c->self, data_len, c->local_maxpacket); | |
1347 | } | |
1348 | if (data_len > c->local_window) { | |
1349 | log("channel %d: rcvd too much data %d, win %d", | |
1350 | c->self, data_len, c->local_window); | |
1351 | xfree(data); | |
1352 | return; | |
1353 | } | |
1354 | c->local_window -= data_len; | |
1355 | }else{ | |
1356 | packet_integrity_check(plen, 4 + 4 + data_len, type); | |
1357 | } | |
7368a6c8 | 1358 | buffer_append(&c->output, data, data_len); |
5260325f | 1359 | xfree(data); |
8efc0c15 | 1360 | } |
6ae2364d | 1361 | void |
188adeb2 | 1362 | channel_input_extended_data(int type, int plen, void *ctxt) |
7e7327a1 | 1363 | { |
1364 | int id; | |
1365 | int tcode; | |
1366 | char *data; | |
1e3b8b07 | 1367 | u_int data_len; |
7e7327a1 | 1368 | Channel *c; |
1369 | ||
1370 | /* Get the channel number and verify it. */ | |
1371 | id = packet_get_int(); | |
1372 | c = channel_lookup(id); | |
1373 | ||
1374 | if (c == NULL) | |
1375 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
1376 | if (c->type != SSH_CHANNEL_OPEN) { | |
1377 | log("channel %d: ext data for non open", id); | |
1378 | return; | |
1379 | } | |
1380 | tcode = packet_get_int(); | |
1381 | if (c->efd == -1 || | |
1382 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
1383 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
1384 | log("channel %d: bad ext data", c->self); | |
1385 | return; | |
1386 | } | |
1387 | data = packet_get_string(&data_len); | |
6ae2364d | 1388 | packet_done(); |
7e7327a1 | 1389 | if (data_len > c->local_window) { |
1390 | log("channel %d: rcvd too much extended_data %d, win %d", | |
1391 | c->self, data_len, c->local_window); | |
1392 | xfree(data); | |
1393 | return; | |
1394 | } | |
de273eef | 1395 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
7e7327a1 | 1396 | c->local_window -= data_len; |
1397 | buffer_append(&c->extended, data, data_len); | |
1398 | xfree(data); | |
1399 | } | |
1400 | ||
8efc0c15 | 1401 | |
aa3378df | 1402 | /* |
1403 | * Returns true if no channel has too much buffered data, and false if one or | |
1404 | * more channel is overfull. | |
1405 | */ | |
8efc0c15 | 1406 | |
6ae2364d | 1407 | int |
5260325f | 1408 | channel_not_very_much_buffered_data() |
8efc0c15 | 1409 | { |
1e3b8b07 | 1410 | u_int i; |
7368a6c8 | 1411 | Channel *c; |
5260325f | 1412 | |
1413 | for (i = 0; i < channels_alloc; i++) { | |
7368a6c8 | 1414 | c = &channels[i]; |
1415 | if (c->type == SSH_CHANNEL_OPEN) { | |
7e7327a1 | 1416 | if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { |
7368a6c8 | 1417 | debug("channel %d: big input buffer %d", |
1418 | c->self, buffer_len(&c->input)); | |
5260325f | 1419 | return 0; |
7368a6c8 | 1420 | } |
1421 | if (buffer_len(&c->output) > packet_get_maxsize()) { | |
1422 | debug("channel %d: big output buffer %d", | |
1423 | c->self, buffer_len(&c->output)); | |
5260325f | 1424 | return 0; |
7368a6c8 | 1425 | } |
5260325f | 1426 | } |
8efc0c15 | 1427 | } |
5260325f | 1428 | return 1; |
8efc0c15 | 1429 | } |
1430 | ||
6ae2364d | 1431 | void |
188adeb2 | 1432 | channel_input_ieof(int type, int plen, void *ctxt) |
7368a6c8 | 1433 | { |
1434 | int id; | |
1435 | Channel *c; | |
1436 | ||
1437 | packet_integrity_check(plen, 4, type); | |
1438 | ||
1439 | id = packet_get_int(); | |
1440 | c = channel_lookup(id); | |
1441 | if (c == NULL) | |
1442 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1443 | chan_rcvd_ieof(c); | |
1444 | } | |
8efc0c15 | 1445 | |
6ae2364d | 1446 | void |
188adeb2 | 1447 | channel_input_close(int type, int plen, void *ctxt) |
8efc0c15 | 1448 | { |
7368a6c8 | 1449 | int id; |
1450 | Channel *c; | |
5260325f | 1451 | |
7368a6c8 | 1452 | packet_integrity_check(plen, 4, type); |
1453 | ||
1454 | id = packet_get_int(); | |
1455 | c = channel_lookup(id); | |
1456 | if (c == NULL) | |
1457 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1458 | |
1459 | /* | |
1460 | * Send a confirmation that we have closed the channel and no more | |
1461 | * data is coming for it. | |
1462 | */ | |
5260325f | 1463 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1464 | packet_put_int(c->remote_id); |
5260325f | 1465 | packet_send(); |
1466 | ||
aa3378df | 1467 | /* |
1468 | * If the channel is in closed state, we have sent a close request, | |
1469 | * and the other side will eventually respond with a confirmation. | |
1470 | * Thus, we cannot free the channel here, because then there would be | |
1471 | * no-one to receive the confirmation. The channel gets freed when | |
1472 | * the confirmation arrives. | |
1473 | */ | |
7368a6c8 | 1474 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1475 | /* |
1476 | * Not a closed channel - mark it as draining, which will | |
1477 | * cause it to be freed later. | |
1478 | */ | |
7368a6c8 | 1479 | buffer_consume(&c->input, buffer_len(&c->input)); |
1480 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; | |
5260325f | 1481 | } |
8efc0c15 | 1482 | } |
1483 | ||
7368a6c8 | 1484 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 1485 | void |
188adeb2 | 1486 | channel_input_oclose(int type, int plen, void *ctxt) |
8efc0c15 | 1487 | { |
7368a6c8 | 1488 | int id = packet_get_int(); |
1489 | Channel *c = channel_lookup(id); | |
1490 | packet_integrity_check(plen, 4, type); | |
1491 | if (c == NULL) | |
1492 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1493 | chan_rcvd_oclose(c); | |
8efc0c15 | 1494 | } |
1495 | ||
6ae2364d | 1496 | void |
188adeb2 | 1497 | channel_input_close_confirmation(int type, int plen, void *ctxt) |
7368a6c8 | 1498 | { |
1499 | int id = packet_get_int(); | |
1500 | Channel *c = channel_lookup(id); | |
1501 | ||
6ae2364d | 1502 | packet_done(); |
7368a6c8 | 1503 | if (c == NULL) |
1504 | packet_disconnect("Received close confirmation for " | |
1505 | "out-of-range channel %d.", id); | |
1506 | if (c->type != SSH_CHANNEL_CLOSED) | |
1507 | packet_disconnect("Received close confirmation for " | |
1508 | "non-closed channel %d (type %d).", id, c->type); | |
1509 | channel_free(c->self); | |
1510 | } | |
8efc0c15 | 1511 | |
6ae2364d | 1512 | void |
188adeb2 | 1513 | channel_input_open_confirmation(int type, int plen, void *ctxt) |
8efc0c15 | 1514 | { |
7368a6c8 | 1515 | int id, remote_id; |
1516 | Channel *c; | |
5260325f | 1517 | |
7e7327a1 | 1518 | if (!compat20) |
1519 | packet_integrity_check(plen, 4 + 4, type); | |
5260325f | 1520 | |
7368a6c8 | 1521 | id = packet_get_int(); |
1522 | c = channel_lookup(id); | |
5260325f | 1523 | |
7368a6c8 | 1524 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1525 | packet_disconnect("Received open confirmation for " | |
1526 | "non-opening channel %d.", id); | |
1527 | remote_id = packet_get_int(); | |
aa3378df | 1528 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1529 | c->remote_id = remote_id; |
1530 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1531 | |
1532 | if (compat20) { | |
1533 | c->remote_window = packet_get_int(); | |
1534 | c->remote_maxpacket = packet_get_int(); | |
6ae2364d | 1535 | packet_done(); |
7e7327a1 | 1536 | if (c->cb_fn != NULL && c->cb_event == type) { |
de273eef | 1537 | debug2("callback start"); |
7e7327a1 | 1538 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1539 | debug2("callback done"); |
7e7327a1 | 1540 | } |
1541 | debug("channel %d: open confirm rwindow %d rmax %d", c->self, | |
1542 | c->remote_window, c->remote_maxpacket); | |
1543 | } | |
8efc0c15 | 1544 | } |
1545 | ||
6ae2364d | 1546 | void |
188adeb2 | 1547 | channel_input_open_failure(int type, int plen, void *ctxt) |
8efc0c15 | 1548 | { |
02a024dd | 1549 | int id, reason; |
1550 | char *msg = NULL, *lang = NULL; | |
7368a6c8 | 1551 | Channel *c; |
5260325f | 1552 | |
7e7327a1 | 1553 | if (!compat20) |
1554 | packet_integrity_check(plen, 4, type); | |
7368a6c8 | 1555 | |
1556 | id = packet_get_int(); | |
1557 | c = channel_lookup(id); | |
1558 | ||
1559 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1560 | packet_disconnect("Received open failure for " | |
1561 | "non-opening channel %d.", id); | |
7e7327a1 | 1562 | if (compat20) { |
02a024dd | 1563 | reason = packet_get_int(); |
1564 | if (packet_remaining() > 0) { | |
1565 | msg = packet_get_string(NULL); | |
1566 | lang = packet_get_string(NULL); | |
1567 | } | |
6ae2364d | 1568 | packet_done(); |
02a024dd | 1569 | log("channel_open_failure: %d: reason %d %s", id, |
1570 | reason, msg ? msg : "<no additional info>"); | |
1571 | if (msg != NULL) | |
1572 | xfree(msg); | |
1573 | if (lang != NULL) | |
1574 | xfree(lang); | |
7e7327a1 | 1575 | } |
5260325f | 1576 | /* Free the channel. This will also close the socket. */ |
7368a6c8 | 1577 | channel_free(id); |
8efc0c15 | 1578 | } |
1579 | ||
7e7327a1 | 1580 | void |
188adeb2 | 1581 | channel_input_channel_request(int type, int plen, void *ctxt) |
7e7327a1 | 1582 | { |
1583 | int id; | |
1584 | Channel *c; | |
1585 | ||
1586 | id = packet_get_int(); | |
1587 | c = channel_lookup(id); | |
1588 | ||
1589 | if (c == NULL || | |
1590 | (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) | |
1591 | packet_disconnect("Received request for " | |
1592 | "non-open channel %d.", id); | |
1593 | if (c->cb_fn != NULL && c->cb_event == type) { | |
de273eef | 1594 | debug2("callback start"); |
7e7327a1 | 1595 | c->cb_fn(c->self, c->cb_arg); |
de273eef | 1596 | debug2("callback done"); |
7e7327a1 | 1597 | } else { |
1598 | char *service = packet_get_string(NULL); | |
94dfb550 | 1599 | debug("channel %d: rcvd request for %s", c->self, service); |
de273eef | 1600 | debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); |
7e7327a1 | 1601 | xfree(service); |
1602 | } | |
1603 | } | |
1604 | ||
6ae2364d | 1605 | void |
188adeb2 | 1606 | channel_input_window_adjust(int type, int plen, void *ctxt) |
7e7327a1 | 1607 | { |
1608 | Channel *c; | |
1609 | int id, adjust; | |
1610 | ||
1611 | if (!compat20) | |
1612 | return; | |
1613 | ||
1614 | /* Get the channel number and verify it. */ | |
1615 | id = packet_get_int(); | |
1616 | c = channel_lookup(id); | |
1617 | ||
1618 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1619 | log("Received window adjust for " | |
1620 | "non-open channel %d.", id); | |
1621 | return; | |
1622 | } | |
1623 | adjust = packet_get_int(); | |
6ae2364d | 1624 | packet_done(); |
de273eef | 1625 | debug2("channel %d: rcvd adjust %d", id, adjust); |
7e7327a1 | 1626 | c->remote_window += adjust; |
1627 | } | |
1628 | ||
aa3378df | 1629 | /* |
1630 | * Stops listening for channels, and removes any unix domain sockets that we | |
1631 | * might have. | |
1632 | */ | |
8efc0c15 | 1633 | |
6ae2364d | 1634 | void |
5260325f | 1635 | channel_stop_listening() |
8efc0c15 | 1636 | { |
5260325f | 1637 | int i; |
1638 | for (i = 0; i < channels_alloc; i++) { | |
1639 | switch (channels[i].type) { | |
1640 | case SSH_CHANNEL_AUTH_SOCKET: | |
1641 | close(channels[i].sock); | |
77bb0bca | 1642 | unlink(channels[i].path); |
5260325f | 1643 | channel_free(i); |
1644 | break; | |
1645 | case SSH_CHANNEL_PORT_LISTENER: | |
fa08c86b | 1646 | case SSH_CHANNEL_RPORT_LISTENER: |
5260325f | 1647 | case SSH_CHANNEL_X11_LISTENER: |
1648 | close(channels[i].sock); | |
1649 | channel_free(i); | |
1650 | break; | |
1651 | default: | |
1652 | break; | |
1653 | } | |
8efc0c15 | 1654 | } |
8efc0c15 | 1655 | } |
1656 | ||
aa3378df | 1657 | /* |
0fbe8c74 | 1658 | * Closes the sockets/fds of all channels. This is used to close extra file |
aa3378df | 1659 | * descriptors after a fork. |
1660 | */ | |
8efc0c15 | 1661 | |
6ae2364d | 1662 | void |
5260325f | 1663 | channel_close_all() |
8efc0c15 | 1664 | { |
5260325f | 1665 | int i; |
0fbe8c74 | 1666 | for (i = 0; i < channels_alloc; i++) |
5260325f | 1667 | if (channels[i].type != SSH_CHANNEL_FREE) |
0fbe8c74 | 1668 | channel_close_fds(&channels[i]); |
8efc0c15 | 1669 | } |
1670 | ||
8efc0c15 | 1671 | /* Returns true if any channel is still open. */ |
1672 | ||
6ae2364d | 1673 | int |
5260325f | 1674 | channel_still_open() |
8efc0c15 | 1675 | { |
1e3b8b07 | 1676 | u_int i; |
5260325f | 1677 | for (i = 0; i < channels_alloc; i++) |
1678 | switch (channels[i].type) { | |
1679 | case SSH_CHANNEL_FREE: | |
1680 | case SSH_CHANNEL_X11_LISTENER: | |
1681 | case SSH_CHANNEL_PORT_LISTENER: | |
fa08c86b | 1682 | case SSH_CHANNEL_RPORT_LISTENER: |
5260325f | 1683 | case SSH_CHANNEL_CLOSED: |
1684 | case SSH_CHANNEL_AUTH_SOCKET: | |
0490e609 | 1685 | case SSH_CHANNEL_DYNAMIC: |
97fb6912 | 1686 | case SSH_CHANNEL_CONNECTING: /* XXX ??? */ |
5260325f | 1687 | continue; |
7e7327a1 | 1688 | case SSH_CHANNEL_LARVAL: |
1689 | if (!compat20) | |
1690 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
1691 | continue; | |
5260325f | 1692 | case SSH_CHANNEL_OPENING: |
1693 | case SSH_CHANNEL_OPEN: | |
1694 | case SSH_CHANNEL_X11_OPEN: | |
1695 | return 1; | |
1696 | case SSH_CHANNEL_INPUT_DRAINING: | |
1697 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
1698 | if (!compat13) | |
1699 | fatal("cannot happen: OUT_DRAIN"); | |
1700 | return 1; | |
1701 | default: | |
1702 | fatal("channel_still_open: bad channel type %d", channels[i].type); | |
1703 | /* NOTREACHED */ | |
1704 | } | |
1705 | return 0; | |
8efc0c15 | 1706 | } |
1707 | ||
aa3378df | 1708 | /* |
1709 | * Returns a message describing the currently open forwarded connections, | |
1710 | * suitable for sending to the client. The message contains crlf pairs for | |
1711 | * newlines. | |
1712 | */ | |
8efc0c15 | 1713 | |
5260325f | 1714 | char * |
1715 | channel_open_message() | |
8efc0c15 | 1716 | { |
5260325f | 1717 | Buffer buffer; |
1718 | int i; | |
1719 | char buf[512], *cp; | |
1720 | ||
1721 | buffer_init(&buffer); | |
1722 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
8efc0c15 | 1723 | buffer_append(&buffer, buf, strlen(buf)); |
5260325f | 1724 | for (i = 0; i < channels_alloc; i++) { |
1725 | Channel *c = &channels[i]; | |
1726 | switch (c->type) { | |
1727 | case SSH_CHANNEL_FREE: | |
1728 | case SSH_CHANNEL_X11_LISTENER: | |
1729 | case SSH_CHANNEL_PORT_LISTENER: | |
fa08c86b | 1730 | case SSH_CHANNEL_RPORT_LISTENER: |
5260325f | 1731 | case SSH_CHANNEL_CLOSED: |
1732 | case SSH_CHANNEL_AUTH_SOCKET: | |
1733 | continue; | |
7e7327a1 | 1734 | case SSH_CHANNEL_LARVAL: |
5260325f | 1735 | case SSH_CHANNEL_OPENING: |
97fb6912 | 1736 | case SSH_CHANNEL_CONNECTING: |
0490e609 | 1737 | case SSH_CHANNEL_DYNAMIC: |
5260325f | 1738 | case SSH_CHANNEL_OPEN: |
1739 | case SSH_CHANNEL_X11_OPEN: | |
1740 | case SSH_CHANNEL_INPUT_DRAINING: | |
1741 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
7368a6c8 | 1742 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", |
48e671d5 | 1743 | c->self, c->remote_name, |
1744 | c->type, c->remote_id, | |
1745 | c->istate, buffer_len(&c->input), | |
7368a6c8 | 1746 | c->ostate, buffer_len(&c->output), |
1747 | c->rfd, c->wfd); | |
5260325f | 1748 | buffer_append(&buffer, buf, strlen(buf)); |
1749 | continue; | |
1750 | default: | |
7368a6c8 | 1751 | fatal("channel_open_message: bad channel type %d", c->type); |
5260325f | 1752 | /* NOTREACHED */ |
1753 | } | |
1754 | } | |
1755 | buffer_append(&buffer, "\0", 1); | |
1756 | cp = xstrdup(buffer_ptr(&buffer)); | |
1757 | buffer_free(&buffer); | |
1758 | return cp; | |
8efc0c15 | 1759 | } |
1760 | ||
aa3378df | 1761 | /* |
1762 | * Initiate forwarding of connections to local port "port" through the secure | |
1763 | * channel to host:port from remote side. | |
1764 | */ | |
02a024dd | 1765 | int |
fa08c86b | 1766 | channel_request_local_forwarding(u_short listen_port, const char *host_to_connect, |
1767 | u_short port_to_connect, int gateway_ports) | |
1768 | { | |
02a024dd | 1769 | return channel_request_forwarding( |
fa08c86b | 1770 | NULL, listen_port, |
1771 | host_to_connect, port_to_connect, | |
1772 | gateway_ports, /*remote_fwd*/ 0); | |
1773 | } | |
8efc0c15 | 1774 | |
fa08c86b | 1775 | /* |
1776 | * If 'remote_fwd' is true we have a '-R style' listener for protocol 2 | |
1777 | * (SSH_CHANNEL_RPORT_LISTENER). | |
1778 | */ | |
02a024dd | 1779 | int |
fa08c86b | 1780 | channel_request_forwarding( |
1781 | const char *listen_address, u_short listen_port, | |
1782 | const char *host_to_connect, u_short port_to_connect, | |
1783 | int gateway_ports, int remote_fwd) | |
8efc0c15 | 1784 | { |
fa08c86b | 1785 | int success, ch, sock, on = 1, ctype; |
48e671d5 | 1786 | struct addrinfo hints, *ai, *aitop; |
1787 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
fa08c86b | 1788 | const char *host; |
aa3378df | 1789 | struct linger linger; |
5260325f | 1790 | |
02a024dd | 1791 | success = 0; |
1792 | ||
fa08c86b | 1793 | if (remote_fwd) { |
1794 | host = listen_address; | |
2b87da3b | 1795 | ctype = SSH_CHANNEL_RPORT_LISTENER; |
fa08c86b | 1796 | } else { |
1797 | host = host_to_connect; | |
1798 | ctype =SSH_CHANNEL_PORT_LISTENER; | |
1799 | } | |
1800 | ||
02a024dd | 1801 | if (strlen(host) > sizeof(channels[0].path) - 1) { |
1802 | error("Forward host name too long."); | |
1803 | return success; | |
1804 | } | |
5260325f | 1805 | |
fa08c86b | 1806 | /* XXX listen_address is currently ignored */ |
aa3378df | 1807 | /* |
48e671d5 | 1808 | * getaddrinfo returns a loopback address if the hostname is |
1809 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 1810 | */ |
48e671d5 | 1811 | memset(&hints, 0, sizeof(hints)); |
1812 | hints.ai_family = IPv4or6; | |
1813 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
1814 | hints.ai_socktype = SOCK_STREAM; | |
fa08c86b | 1815 | snprintf(strport, sizeof strport, "%d", listen_port); |
48e671d5 | 1816 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) |
1817 | packet_disconnect("getaddrinfo: fatal error"); | |
1818 | ||
48e671d5 | 1819 | for (ai = aitop; ai; ai = ai->ai_next) { |
1820 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1821 | continue; | |
1822 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
1823 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
fa08c86b | 1824 | error("channel_request_forwarding: getnameinfo failed"); |
48e671d5 | 1825 | continue; |
1826 | } | |
1827 | /* Create a port to listen for the host. */ | |
1828 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1829 | if (sock < 0) { | |
1830 | /* this is no error since kernel may not support ipv6 */ | |
1831 | verbose("socket: %.100s", strerror(errno)); | |
1832 | continue; | |
1833 | } | |
1834 | /* | |
1835 | * Set socket options. We would like the socket to disappear | |
1836 | * as soon as it has been closed for whatever reason. | |
1837 | */ | |
1838 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); | |
1839 | linger.l_onoff = 1; | |
1840 | linger.l_linger = 5; | |
1841 | setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); | |
1842 | debug("Local forwarding listening on %s port %s.", ntop, strport); | |
1843 | ||
1844 | /* Bind the socket to the address. */ | |
1845 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1846 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 1847 | if (!ai->ai_next) |
1848 | error("bind: %.100s", strerror(errno)); | |
1849 | else | |
1850 | verbose("bind: %.100s", strerror(errno)); | |
2b87da3b | 1851 | |
48e671d5 | 1852 | close(sock); |
1853 | continue; | |
1854 | } | |
1855 | /* Start listening for connections on the socket. */ | |
1856 | if (listen(sock, 5) < 0) { | |
1857 | error("listen: %.100s", strerror(errno)); | |
1858 | close(sock); | |
1859 | continue; | |
1860 | } | |
1861 | /* Allocate a channel number for the socket. */ | |
fa08c86b | 1862 | ch = channel_new("port listener", ctype, sock, sock, -1, |
0b242b12 | 1863 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
a22aff1f | 1864 | 0, xstrdup("port listener"), 1); |
48e671d5 | 1865 | strlcpy(channels[ch].path, host, sizeof(channels[ch].path)); |
fa08c86b | 1866 | channels[ch].host_port = port_to_connect; |
1867 | channels[ch].listening_port = listen_port; | |
48e671d5 | 1868 | success = 1; |
1869 | } | |
1870 | if (success == 0) | |
02a024dd | 1871 | error("channel_request_forwarding: cannot listen to port: %d", |
1872 | listen_port); | |
48e671d5 | 1873 | freeaddrinfo(aitop); |
02a024dd | 1874 | return success; |
5260325f | 1875 | } |
8efc0c15 | 1876 | |
aa3378df | 1877 | /* |
1878 | * Initiate forwarding of connections to port "port" on remote host through | |
1879 | * the secure channel to host:port from local side. | |
1880 | */ | |
8efc0c15 | 1881 | |
6ae2364d | 1882 | void |
fa08c86b | 1883 | channel_request_remote_forwarding(u_short listen_port, |
1884 | const char *host_to_connect, u_short port_to_connect) | |
8efc0c15 | 1885 | { |
fa08c86b | 1886 | int payload_len, type, success = 0; |
1887 | ||
5260325f | 1888 | /* Record locally that connection to this host/port is permitted. */ |
1889 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
1890 | fatal("channel_request_remote_forwarding: too many forwards"); | |
1891 | ||
5260325f | 1892 | /* Send the forward request to the remote side. */ |
7e7327a1 | 1893 | if (compat20) { |
1894 | const char *address_to_bind = "0.0.0.0"; | |
1895 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
1896 | packet_put_cstring("tcpip-forward"); | |
1897 | packet_put_char(0); /* boolean: want reply */ | |
1898 | packet_put_cstring(address_to_bind); | |
1899 | packet_put_int(listen_port); | |
fa08c86b | 1900 | packet_send(); |
1901 | packet_write_wait(); | |
1902 | /* Assume that server accepts the request */ | |
1903 | success = 1; | |
7e7327a1 | 1904 | } else { |
1905 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 1906 | packet_put_int(listen_port); |
d6f24e45 | 1907 | packet_put_cstring(host_to_connect); |
1908 | packet_put_int(port_to_connect); | |
7e7327a1 | 1909 | packet_send(); |
1910 | packet_write_wait(); | |
fa08c86b | 1911 | |
1912 | /* Wait for response from the remote side. */ | |
1913 | type = packet_read(&payload_len); | |
1914 | switch (type) { | |
1915 | case SSH_SMSG_SUCCESS: | |
1916 | success = 1; | |
1917 | break; | |
1918 | case SSH_SMSG_FAILURE: | |
1919 | log("Warning: Server denied remote port forwarding."); | |
1920 | break; | |
1921 | default: | |
1922 | /* Unknown packet */ | |
1923 | packet_disconnect("Protocol error for port forward request:" | |
1924 | "received packet type %d.", type); | |
1925 | } | |
1926 | } | |
1927 | if (success) { | |
1928 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); | |
1929 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
1930 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
1931 | num_permitted_opens++; | |
7e7327a1 | 1932 | } |
8efc0c15 | 1933 | } |
1934 | ||
aa3378df | 1935 | /* |
1936 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
1937 | * listening for the port, and sends back a success reply (or disconnect | |
1938 | * message if there was an error). This never returns if there was an error. | |
1939 | */ | |
8efc0c15 | 1940 | |
6ae2364d | 1941 | void |
1d1ffb87 | 1942 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 1943 | { |
57112b5a | 1944 | u_short port, host_port; |
5260325f | 1945 | char *hostname; |
1946 | ||
1947 | /* Get arguments from the packet. */ | |
1948 | port = packet_get_int(); | |
1949 | hostname = packet_get_string(NULL); | |
1950 | host_port = packet_get_int(); | |
1951 | ||
3c62e7eb | 1952 | #ifndef HAVE_CYGWIN |
aa3378df | 1953 | /* |
1954 | * Check that an unprivileged user is not trying to forward a | |
1955 | * privileged port. | |
1956 | */ | |
5260325f | 1957 | if (port < IPPORT_RESERVED && !is_root) |
1958 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
1959 | port); | |
3c62e7eb | 1960 | #endif |
fa08c86b | 1961 | /* Initiate forwarding */ |
1d1ffb87 | 1962 | channel_request_local_forwarding(port, hostname, host_port, gateway_ports); |
5260325f | 1963 | |
1964 | /* Free the argument string. */ | |
1965 | xfree(hostname); | |
8efc0c15 | 1966 | } |
1967 | ||
01794848 | 1968 | /* |
1969 | * Permits opening to any host/port if permitted_opens[] is empty. This is | |
1970 | * usually called by the server, because the user could connect to any port | |
1971 | * anyway, and the server has no way to know but to trust the client anyway. | |
1972 | */ | |
1973 | void | |
1974 | channel_permit_all_opens() | |
1975 | { | |
1976 | if (num_permitted_opens == 0) | |
1977 | all_opens_permitted = 1; | |
1978 | } | |
1979 | ||
cd332296 | 1980 | void |
01794848 | 1981 | channel_add_permitted_opens(char *host, int port) |
1982 | { | |
1983 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
1984 | fatal("channel_request_remote_forwarding: too many forwards"); | |
1985 | debug("allow port forwarding to host %s port %d", host, port); | |
1986 | ||
1987 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); | |
1988 | permitted_opens[num_permitted_opens].port_to_connect = port; | |
1989 | num_permitted_opens++; | |
1990 | ||
1991 | all_opens_permitted = 0; | |
1992 | } | |
1993 | ||
cd332296 | 1994 | void |
01794848 | 1995 | channel_clear_permitted_opens(void) |
1996 | { | |
1997 | int i; | |
1998 | ||
1999 | for (i = 0; i < num_permitted_opens; i++) | |
2000 | xfree(permitted_opens[i].host_to_connect); | |
2001 | num_permitted_opens = 0; | |
2002 | ||
2003 | } | |
2004 | ||
2005 | ||
2006 | /* return socket to remote host, port */ | |
7368a6c8 | 2007 | int |
01794848 | 2008 | connect_to(const char *host, u_short port) |
8efc0c15 | 2009 | { |
48e671d5 | 2010 | struct addrinfo hints, *ai, *aitop; |
2011 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
2012 | int gaierr; | |
7368a6c8 | 2013 | int sock = -1; |
48e671d5 | 2014 | |
2015 | memset(&hints, 0, sizeof(hints)); | |
2016 | hints.ai_family = IPv4or6; | |
2017 | hints.ai_socktype = SOCK_STREAM; | |
01794848 | 2018 | snprintf(strport, sizeof strport, "%d", port); |
48e671d5 | 2019 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { |
01794848 | 2020 | error("connect_to %.100s: unknown host (%s)", host, |
2021 | gai_strerror(gaierr)); | |
7368a6c8 | 2022 | return -1; |
48e671d5 | 2023 | } |
48e671d5 | 2024 | for (ai = aitop; ai; ai = ai->ai_next) { |
2025 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2026 | continue; | |
2027 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
2028 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
01794848 | 2029 | error("connect_to: getnameinfo failed"); |
48e671d5 | 2030 | continue; |
5260325f | 2031 | } |
48e671d5 | 2032 | sock = socket(ai->ai_family, SOCK_STREAM, 0); |
2033 | if (sock < 0) { | |
2034 | error("socket: %.100s", strerror(errno)); | |
2035 | continue; | |
5260325f | 2036 | } |
eea39c02 | 2037 | if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) |
97fb6912 | 2038 | fatal("connect_to: F_SETFL: %s", strerror(errno)); |
97fb6912 | 2039 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 && |
2040 | errno != EINPROGRESS) { | |
01794848 | 2041 | error("connect_to %.100s port %s: %.100s", ntop, strport, |
48e671d5 | 2042 | strerror(errno)); |
2043 | close(sock); | |
2b87da3b | 2044 | continue; /* fail -- try next */ |
48e671d5 | 2045 | } |
2046 | break; /* success */ | |
5260325f | 2047 | |
5260325f | 2048 | } |
48e671d5 | 2049 | freeaddrinfo(aitop); |
48e671d5 | 2050 | if (!ai) { |
01794848 | 2051 | error("connect_to %.100s port %d: failed.", host, port); |
7368a6c8 | 2052 | return -1; |
8efc0c15 | 2053 | } |
7368a6c8 | 2054 | /* success */ |
2055 | return sock; | |
2056 | } | |
01794848 | 2057 | |
fa08c86b | 2058 | int |
2059 | channel_connect_by_listen_adress(u_short listen_port) | |
2060 | { | |
2061 | int i; | |
01794848 | 2062 | |
fa08c86b | 2063 | for (i = 0; i < num_permitted_opens; i++) |
2064 | if (permitted_opens[i].listen_port == listen_port) | |
01794848 | 2065 | return connect_to( |
fa08c86b | 2066 | permitted_opens[i].host_to_connect, |
2067 | permitted_opens[i].port_to_connect); | |
0b6fbf03 | 2068 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
2069 | listen_port); | |
fa08c86b | 2070 | return -1; |
2071 | } | |
48e671d5 | 2072 | |
01794848 | 2073 | /* Check if connecting to that port is permitted and connect. */ |
2074 | int | |
2075 | channel_connect_to(const char *host, u_short port) | |
2076 | { | |
2077 | int i, permit; | |
2078 | ||
2079 | permit = all_opens_permitted; | |
2080 | if (!permit) { | |
2081 | for (i = 0; i < num_permitted_opens; i++) | |
2082 | if (permitted_opens[i].port_to_connect == port && | |
2083 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
2084 | permit = 1; | |
2085 | ||
2086 | } | |
2087 | if (!permit) { | |
2088 | log("Received request to connect to host %.100s port %d, " | |
2089 | "but the request was denied.", host, port); | |
2090 | return -1; | |
2091 | } | |
2092 | return connect_to(host, port); | |
2093 | } | |
2094 | ||
7368a6c8 | 2095 | /* |
2096 | * This is called after receiving PORT_OPEN message. This attempts to | |
2097 | * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION | |
2098 | * or CHANNEL_OPEN_FAILURE. | |
2099 | */ | |
5260325f | 2100 | |
6ae2364d | 2101 | void |
188adeb2 | 2102 | channel_input_port_open(int type, int plen, void *ctxt) |
7368a6c8 | 2103 | { |
2104 | u_short host_port; | |
2105 | char *host, *originator_string; | |
01794848 | 2106 | int remote_channel, sock = -1, newch; |
5260325f | 2107 | |
7368a6c8 | 2108 | remote_channel = packet_get_int(); |
01794848 | 2109 | host = packet_get_string(NULL); |
7368a6c8 | 2110 | host_port = packet_get_int(); |
5260325f | 2111 | |
7368a6c8 | 2112 | if (have_hostname_in_open) { |
01794848 | 2113 | originator_string = packet_get_string(NULL); |
7368a6c8 | 2114 | } else { |
2115 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
7368a6c8 | 2116 | } |
01794848 | 2117 | packet_done(); |
2118 | sock = channel_connect_to(host, host_port); | |
2119 | if (sock != -1) { | |
97fb6912 | 2120 | newch = channel_allocate(SSH_CHANNEL_CONNECTING, |
2121 | sock, originator_string); | |
7368a6c8 | 2122 | channels[newch].remote_id = remote_channel; |
2123 | ||
01794848 | 2124 | /*XXX delay answer? */ |
7368a6c8 | 2125 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); |
2126 | packet_put_int(remote_channel); | |
2127 | packet_put_int(newch); | |
2128 | packet_send(); | |
2129 | } else { | |
2130 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2131 | packet_put_int(remote_channel); | |
2132 | packet_send(); | |
2133 | } | |
2134 | xfree(host); | |
8efc0c15 | 2135 | } |
2136 | ||
aa3378df | 2137 | /* |
2138 | * Creates an internet domain socket for listening for X11 connections. | |
2139 | * Returns a suitable value for the DISPLAY variable, or NULL if an error | |
2140 | * occurs. | |
2141 | */ | |
8efc0c15 | 2142 | |
48e671d5 | 2143 | #define NUM_SOCKS 10 |
2144 | ||
5260325f | 2145 | char * |
95f1eccc | 2146 | x11_create_display_inet(int screen_number, int x11_display_offset) |
8efc0c15 | 2147 | { |
57112b5a | 2148 | int display_number, sock; |
2149 | u_short port; | |
48e671d5 | 2150 | struct addrinfo hints, *ai, *aitop; |
2151 | char strport[NI_MAXSERV]; | |
2152 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
2153 | char display[512]; | |
5260325f | 2154 | char hostname[MAXHOSTNAMELEN]; |
2155 | ||
95f1eccc | 2156 | for (display_number = x11_display_offset; |
5260325f | 2157 | display_number < MAX_DISPLAYS; |
2158 | display_number++) { | |
2159 | port = 6000 + display_number; | |
48e671d5 | 2160 | memset(&hints, 0, sizeof(hints)); |
2161 | hints.ai_family = IPv4or6; | |
2162 | hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */ | |
2163 | hints.ai_socktype = SOCK_STREAM; | |
2164 | snprintf(strport, sizeof strport, "%d", port); | |
2165 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
2166 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
5260325f | 2167 | return NULL; |
2168 | } | |
48e671d5 | 2169 | for (ai = aitop; ai; ai = ai->ai_next) { |
2170 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
2171 | continue; | |
2172 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2173 | if (sock < 0) { | |
4ee81249 | 2174 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) { |
80a44451 | 2175 | error("socket: %.100s", strerror(errno)); |
2176 | return NULL; | |
2177 | } else { | |
22d89d24 | 2178 | debug("x11_create_display_inet: Socket family %d not supported", |
2179 | ai->ai_family); | |
80a44451 | 2180 | continue; |
2181 | } | |
48e671d5 | 2182 | } |
2183 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2184 | debug("bind port %d: %.100s", port, strerror(errno)); | |
2185 | shutdown(sock, SHUT_RDWR); | |
2186 | close(sock); | |
16218745 | 2187 | |
2188 | if (ai->ai_next) | |
2189 | continue; | |
2190 | ||
48e671d5 | 2191 | for (n = 0; n < num_socks; n++) { |
2192 | shutdown(socks[n], SHUT_RDWR); | |
2193 | close(socks[n]); | |
2194 | } | |
2195 | num_socks = 0; | |
2196 | break; | |
2197 | } | |
2198 | socks[num_socks++] = sock; | |
80faa19f | 2199 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 2200 | if (num_socks == NUM_SOCKS) |
2201 | break; | |
80faa19f | 2202 | #else |
2203 | break; | |
2204 | #endif | |
5260325f | 2205 | } |
4ccb01d6 | 2206 | freeaddrinfo(aitop); |
48e671d5 | 2207 | if (num_socks > 0) |
2208 | break; | |
5260325f | 2209 | } |
2210 | if (display_number >= MAX_DISPLAYS) { | |
2211 | error("Failed to allocate internet-domain X11 display socket."); | |
2212 | return NULL; | |
8efc0c15 | 2213 | } |
5260325f | 2214 | /* Start listening for connections on the socket. */ |
48e671d5 | 2215 | for (n = 0; n < num_socks; n++) { |
2216 | sock = socks[n]; | |
2217 | if (listen(sock, 5) < 0) { | |
2218 | error("listen: %.100s", strerror(errno)); | |
2219 | shutdown(sock, SHUT_RDWR); | |
2220 | close(sock); | |
2221 | return NULL; | |
2222 | } | |
8efc0c15 | 2223 | } |
48e671d5 | 2224 | |
5260325f | 2225 | /* Set up a suitable value for the DISPLAY variable. */ |
2226 | if (gethostname(hostname, sizeof(hostname)) < 0) | |
2227 | fatal("gethostname: %.100s", strerror(errno)); | |
a7effaac | 2228 | |
2229 | #ifdef IPADDR_IN_DISPLAY | |
2b87da3b | 2230 | /* |
a7effaac | 2231 | * HPUX detects the local hostname in the DISPLAY variable and tries |
2232 | * to set up a shared memory connection to the server, which it | |
2233 | * incorrectly supposes to be local. | |
2234 | * | |
2235 | * The workaround - as used in later $$H and other programs - is | |
2236 | * is to set display to the host's IP address. | |
2237 | */ | |
2238 | { | |
2239 | struct hostent *he; | |
2240 | struct in_addr my_addr; | |
2241 | ||
2242 | he = gethostbyname(hostname); | |
2243 | if (he == NULL) { | |
2244 | error("[X11-broken-fwd-hostname-workaround] Could not get " | |
2245 | "IP address for hostname %s.", hostname); | |
2246 | ||
2247 | packet_send_debug("[X11-broken-fwd-hostname-workaround]" | |
2248 | "Could not get IP address for hostname %s.", hostname); | |
2249 | ||
2250 | shutdown(sock, SHUT_RDWR); | |
2251 | close(sock); | |
2252 | ||
2253 | return NULL; | |
2254 | } | |
2255 | ||
2256 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
2257 | ||
2258 | /* Set DISPLAY to <ip address>:screen.display */ | |
2b87da3b | 2259 | snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr), |
74141647 | 2260 | display_number, screen_number); |
a7effaac | 2261 | } |
2262 | #else /* IPADDR_IN_DISPLAY */ | |
2263 | /* Just set DISPLAY to hostname:screen.display */ | |
48e671d5 | 2264 | snprintf(display, sizeof display, "%.400s:%d.%d", hostname, |
74141647 | 2265 | display_number, screen_number); |
a7effaac | 2266 | #endif /* IPADDR_IN_DISPLAY */ |
5260325f | 2267 | |
48e671d5 | 2268 | /* Allocate a channel for each socket. */ |
2269 | for (n = 0; n < num_socks; n++) { | |
2270 | sock = socks[n]; | |
0b242b12 | 2271 | (void) channel_new("x11 listener", |
2272 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, | |
2273 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
a22aff1f | 2274 | 0, xstrdup("X11 inet listener"), 1); |
48e671d5 | 2275 | } |
5260325f | 2276 | |
2277 | /* Return a suitable value for the DISPLAY environment variable. */ | |
48e671d5 | 2278 | return xstrdup(display); |
8efc0c15 | 2279 | } |
2280 | ||
2281 | #ifndef X_UNIX_PATH | |
2282 | #define X_UNIX_PATH "/tmp/.X11-unix/X" | |
2283 | #endif | |
2284 | ||
2285 | static | |
2286 | int | |
1e3b8b07 | 2287 | connect_local_xsocket(u_int dnr) |
8efc0c15 | 2288 | { |
5260325f | 2289 | static const char *const x_sockets[] = { |
2290 | X_UNIX_PATH "%u", | |
2291 | "/var/X/.X11-unix/X" "%u", | |
2292 | "/usr/spool/sockets/X11/" "%u", | |
2293 | NULL | |
2294 | }; | |
2295 | int sock; | |
2296 | struct sockaddr_un addr; | |
2297 | const char *const * path; | |
2298 | ||
2299 | for (path = x_sockets; *path; ++path) { | |
2300 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2301 | if (sock < 0) | |
2302 | error("socket: %.100s", strerror(errno)); | |
2303 | memset(&addr, 0, sizeof(addr)); | |
2304 | addr.sun_family = AF_UNIX; | |
2305 | snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr); | |
2306 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
2307 | return sock; | |
2308 | close(sock); | |
2309 | } | |
2310 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); | |
2311 | return -1; | |
8efc0c15 | 2312 | } |
2313 | ||
0b242b12 | 2314 | int |
2315 | x11_connect_display(void) | |
8efc0c15 | 2316 | { |
0b242b12 | 2317 | int display_number, sock = 0; |
5260325f | 2318 | const char *display; |
0b242b12 | 2319 | char buf[1024], *cp; |
48e671d5 | 2320 | struct addrinfo hints, *ai, *aitop; |
2321 | char strport[NI_MAXSERV]; | |
2322 | int gaierr; | |
5260325f | 2323 | |
5260325f | 2324 | /* Try to open a socket for the local X server. */ |
2325 | display = getenv("DISPLAY"); | |
2326 | if (!display) { | |
2327 | error("DISPLAY not set."); | |
0b242b12 | 2328 | return -1; |
5260325f | 2329 | } |
aa3378df | 2330 | /* |
2331 | * Now we decode the value of the DISPLAY variable and make a | |
2332 | * connection to the real X server. | |
2333 | */ | |
2334 | ||
2335 | /* | |
2336 | * Check if it is a unix domain socket. Unix domain displays are in | |
2337 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
2338 | */ | |
5260325f | 2339 | if (strncmp(display, "unix:", 5) == 0 || |
2340 | display[0] == ':') { | |
2341 | /* Connect to the unix domain socket. */ | |
2342 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
2343 | error("Could not parse display number from DISPLAY: %.100s", | |
2344 | display); | |
0b242b12 | 2345 | return -1; |
5260325f | 2346 | } |
2347 | /* Create a socket. */ | |
2348 | sock = connect_local_xsocket(display_number); | |
2349 | if (sock < 0) | |
0b242b12 | 2350 | return -1; |
5260325f | 2351 | |
2352 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 2353 | return sock; |
5260325f | 2354 | } |
aa3378df | 2355 | /* |
2356 | * Connect to an inet socket. The DISPLAY value is supposedly | |
2357 | * hostname:d[.s], where hostname may also be numeric IP address. | |
2358 | */ | |
5260325f | 2359 | strncpy(buf, display, sizeof(buf)); |
2360 | buf[sizeof(buf) - 1] = 0; | |
2361 | cp = strchr(buf, ':'); | |
2362 | if (!cp) { | |
2363 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 2364 | return -1; |
5260325f | 2365 | } |
2366 | *cp = 0; | |
aa3378df | 2367 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 2368 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
2369 | error("Could not parse display number from DISPLAY: %.100s", | |
2370 | display); | |
0b242b12 | 2371 | return -1; |
5260325f | 2372 | } |
5260325f | 2373 | |
48e671d5 | 2374 | /* Look up the host address */ |
2375 | memset(&hints, 0, sizeof(hints)); | |
2376 | hints.ai_family = IPv4or6; | |
2377 | hints.ai_socktype = SOCK_STREAM; | |
2378 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
2379 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
2380 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 2381 | return -1; |
8efc0c15 | 2382 | } |
48e671d5 | 2383 | for (ai = aitop; ai; ai = ai->ai_next) { |
2384 | /* Create a socket. */ | |
2385 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
2386 | if (sock < 0) { | |
2387 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 2388 | continue; |
2389 | } | |
2390 | /* Connect it to the display. */ | |
2391 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
2392 | debug("connect %.100s port %d: %.100s", buf, | |
2393 | 6000 + display_number, strerror(errno)); | |
2394 | close(sock); | |
2395 | continue; | |
2396 | } | |
2397 | /* Success */ | |
2398 | break; | |
48e671d5 | 2399 | } |
48e671d5 | 2400 | freeaddrinfo(aitop); |
2401 | if (!ai) { | |
6ae2364d | 2402 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 2403 | strerror(errno)); |
0b242b12 | 2404 | return -1; |
8efc0c15 | 2405 | } |
0b242b12 | 2406 | return sock; |
2407 | } | |
5260325f | 2408 | |
0b242b12 | 2409 | /* |
2410 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
2411 | * the remote channel number. We should do whatever we want, and respond | |
2412 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
2413 | */ | |
5260325f | 2414 | |
0b242b12 | 2415 | void |
188adeb2 | 2416 | x11_input_open(int type, int plen, void *ctxt) |
0b242b12 | 2417 | { |
2418 | int remote_channel, sock = 0, newch; | |
2419 | char *remote_host; | |
1e3b8b07 | 2420 | u_int remote_len; |
5260325f | 2421 | |
0b242b12 | 2422 | /* Get remote channel number. */ |
2423 | remote_channel = packet_get_int(); | |
5260325f | 2424 | |
0b242b12 | 2425 | /* Get remote originator name. */ |
2426 | if (have_hostname_in_open) { | |
2427 | remote_host = packet_get_string(&remote_len); | |
2428 | remote_len += 4; | |
2429 | } else { | |
2430 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
2431 | remote_len = 0; | |
2432 | } | |
2433 | ||
2434 | debug("Received X11 open request."); | |
2435 | packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN); | |
2436 | ||
2437 | /* Obtain a connection to the real X display. */ | |
2438 | sock = x11_connect_display(); | |
2439 | if (sock == -1) { | |
2440 | /* Send refusal to the remote host. */ | |
2441 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2442 | packet_put_int(remote_channel); | |
2443 | packet_send(); | |
2444 | } else { | |
2445 | /* Allocate a channel for this connection. */ | |
2446 | newch = channel_allocate( | |
2447 | (x11_saved_proto == NULL) ? | |
2448 | SSH_CHANNEL_OPEN : SSH_CHANNEL_X11_OPEN, | |
2449 | sock, remote_host); | |
2450 | channels[newch].remote_id = remote_channel; | |
2451 | ||
2452 | /* Send a confirmation to the remote host. */ | |
2453 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2454 | packet_put_int(remote_channel); | |
2455 | packet_put_int(newch); | |
2456 | packet_send(); | |
2457 | } | |
8efc0c15 | 2458 | } |
2459 | ||
a22aff1f | 2460 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
2461 | void | |
2462 | deny_input_open(int type, int plen, void *ctxt) | |
2463 | { | |
2464 | int rchan = packet_get_int(); | |
2465 | switch(type){ | |
2466 | case SSH_SMSG_AGENT_OPEN: | |
2467 | error("Warning: ssh server tried agent forwarding."); | |
2468 | break; | |
2469 | case SSH_SMSG_X11_OPEN: | |
2470 | error("Warning: ssh server tried X11 forwarding."); | |
2471 | break; | |
2472 | default: | |
2473 | error("deny_input_open: type %d plen %d", type, plen); | |
2474 | break; | |
2475 | } | |
2476 | error("Warning: this is probably a break in attempt by a malicious server."); | |
2477 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2478 | packet_put_int(rchan); | |
2479 | packet_send(); | |
2480 | } | |
2481 | ||
aa3378df | 2482 | /* |
2483 | * Requests forwarding of X11 connections, generates fake authentication | |
2484 | * data, and enables authentication spoofing. | |
2485 | */ | |
8efc0c15 | 2486 | |
6ae2364d | 2487 | void |
0b242b12 | 2488 | x11_request_forwarding_with_spoofing(int client_session_id, |
2489 | const char *proto, const char *data) | |
8efc0c15 | 2490 | { |
1e3b8b07 | 2491 | u_int data_len = (u_int) strlen(data) / 2; |
ca910e13 | 2492 | u_int i, value, len; |
5260325f | 2493 | char *new_data; |
2494 | int screen_number; | |
2495 | const char *cp; | |
2496 | u_int32_t rand = 0; | |
2497 | ||
2498 | cp = getenv("DISPLAY"); | |
2499 | if (cp) | |
2500 | cp = strchr(cp, ':'); | |
2501 | if (cp) | |
2502 | cp = strchr(cp, '.'); | |
2503 | if (cp) | |
2504 | screen_number = atoi(cp + 1); | |
2505 | else | |
2506 | screen_number = 0; | |
2507 | ||
2508 | /* Save protocol name. */ | |
2509 | x11_saved_proto = xstrdup(proto); | |
2510 | ||
aa3378df | 2511 | /* |
2512 | * Extract real authentication data and generate fake data of the | |
2513 | * same length. | |
2514 | */ | |
5260325f | 2515 | x11_saved_data = xmalloc(data_len); |
2516 | x11_fake_data = xmalloc(data_len); | |
2517 | for (i = 0; i < data_len; i++) { | |
2518 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
2519 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
2520 | if (i % 4 == 0) | |
2521 | rand = arc4random(); | |
2522 | x11_saved_data[i] = value; | |
2523 | x11_fake_data[i] = rand & 0xff; | |
2524 | rand >>= 8; | |
2525 | } | |
2526 | x11_saved_data_len = data_len; | |
2527 | x11_fake_data_len = data_len; | |
2528 | ||
2529 | /* Convert the fake data into hex. */ | |
ca910e13 | 2530 | len = 2 * data_len + 1; |
2531 | new_data = xmalloc(len); | |
5260325f | 2532 | for (i = 0; i < data_len; i++) |
ca910e13 | 2533 | snprintf(new_data + 2 * i, len - 2 * i, |
2534 | "%02x", (u_char) x11_fake_data[i]); | |
5260325f | 2535 | |
2536 | /* Send the request packet. */ | |
0b242b12 | 2537 | if (compat20) { |
2538 | channel_request_start(client_session_id, "x11-req", 0); | |
2539 | packet_put_char(0); /* XXX bool single connection */ | |
2540 | } else { | |
2541 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
2542 | } | |
2543 | packet_put_cstring(proto); | |
2544 | packet_put_cstring(new_data); | |
5260325f | 2545 | packet_put_int(screen_number); |
2546 | packet_send(); | |
2547 | packet_write_wait(); | |
2548 | xfree(new_data); | |
8efc0c15 | 2549 | } |
2550 | ||
2551 | /* Sends a message to the server to request authentication fd forwarding. */ | |
2552 | ||
6ae2364d | 2553 | void |
5260325f | 2554 | auth_request_forwarding() |
8efc0c15 | 2555 | { |
5260325f | 2556 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2557 | packet_send(); | |
2558 | packet_write_wait(); | |
8efc0c15 | 2559 | } |
2560 | ||
aa3378df | 2561 | /* |
2562 | * Returns the name of the forwarded authentication socket. Returns NULL if | |
2563 | * there is no forwarded authentication socket. The returned value points to | |
2564 | * a static buffer. | |
2565 | */ | |
8efc0c15 | 2566 | |
5260325f | 2567 | char * |
2568 | auth_get_socket_name() | |
8efc0c15 | 2569 | { |
5260325f | 2570 | return channel_forwarded_auth_socket_name; |
8efc0c15 | 2571 | } |
2572 | ||
2573 | /* removes the agent forwarding socket */ | |
2574 | ||
6ae2364d | 2575 | void |
5260325f | 2576 | cleanup_socket(void) |
2577 | { | |
77bb0bca | 2578 | unlink(channel_forwarded_auth_socket_name); |
5260325f | 2579 | rmdir(channel_forwarded_auth_socket_dir); |
8efc0c15 | 2580 | } |
2581 | ||
aa3378df | 2582 | /* |
fa649821 | 2583 | * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
aa3378df | 2584 | * This starts forwarding authentication requests. |
2585 | */ | |
8efc0c15 | 2586 | |
fa649821 | 2587 | int |
5260325f | 2588 | auth_input_request_forwarding(struct passwd * pw) |
8efc0c15 | 2589 | { |
5260325f | 2590 | int sock, newch; |
2591 | struct sockaddr_un sunaddr; | |
2592 | ||
2593 | if (auth_get_socket_name() != NULL) | |
2594 | fatal("Protocol error: authentication forwarding requested twice."); | |
2595 | ||
2596 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
63bd8c36 | 2597 | temporarily_use_uid(pw); |
5260325f | 2598 | |
2599 | /* Allocate a buffer for the socket name, and format the name. */ | |
2600 | channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME); | |
2601 | channel_forwarded_auth_socket_dir = xmalloc(MAX_SOCKET_NAME); | |
2602 | strlcpy(channel_forwarded_auth_socket_dir, "/tmp/ssh-XXXXXXXX", MAX_SOCKET_NAME); | |
2603 | ||
2604 | /* Create private directory for socket */ | |
fa649821 | 2605 | if (mkdtemp(channel_forwarded_auth_socket_dir) == NULL) { |
2606 | packet_send_debug("Agent forwarding disabled: mkdtemp() failed: %.100s", | |
2607 | strerror(errno)); | |
2608 | restore_uid(); | |
2609 | xfree(channel_forwarded_auth_socket_name); | |
2610 | xfree(channel_forwarded_auth_socket_dir); | |
2611 | channel_forwarded_auth_socket_name = NULL; | |
2612 | channel_forwarded_auth_socket_dir = NULL; | |
2613 | return 0; | |
2614 | } | |
5260325f | 2615 | snprintf(channel_forwarded_auth_socket_name, MAX_SOCKET_NAME, "%s/agent.%d", |
2616 | channel_forwarded_auth_socket_dir, (int) getpid()); | |
2617 | ||
2618 | if (atexit(cleanup_socket) < 0) { | |
2619 | int saved = errno; | |
2620 | cleanup_socket(); | |
2621 | packet_disconnect("socket: %.100s", strerror(saved)); | |
2622 | } | |
2623 | /* Create the socket. */ | |
2624 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2625 | if (sock < 0) | |
2626 | packet_disconnect("socket: %.100s", strerror(errno)); | |
2627 | ||
2628 | /* Bind it to the name. */ | |
2629 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
2630 | sunaddr.sun_family = AF_UNIX; | |
2631 | strncpy(sunaddr.sun_path, channel_forwarded_auth_socket_name, | |
2632 | sizeof(sunaddr.sun_path)); | |
2633 | ||
2634 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
2635 | packet_disconnect("bind: %.100s", strerror(errno)); | |
2636 | ||
2637 | /* Restore the privileged uid. */ | |
2638 | restore_uid(); | |
2639 | ||
2640 | /* Start listening on the socket. */ | |
2641 | if (listen(sock, 5) < 0) | |
2642 | packet_disconnect("listen: %.100s", strerror(errno)); | |
2643 | ||
2644 | /* Allocate a channel for the authentication agent socket. */ | |
fa08c86b | 2645 | newch = channel_new("auth socket", |
2646 | SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1, | |
2647 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
2648 | 0, xstrdup("auth socket"), 1); | |
2649 | ||
a408af76 | 2650 | strlcpy(channels[newch].path, channel_forwarded_auth_socket_name, |
2651 | sizeof(channels[newch].path)); | |
fa649821 | 2652 | return 1; |
8efc0c15 | 2653 | } |
2654 | ||
2655 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ | |
2656 | ||
6ae2364d | 2657 | void |
188adeb2 | 2658 | auth_input_open_request(int type, int plen, void *ctxt) |
8efc0c15 | 2659 | { |
5260325f | 2660 | int remch, sock, newch; |
2661 | char *dummyname; | |
2662 | ||
7368a6c8 | 2663 | packet_integrity_check(plen, 4, type); |
2664 | ||
5260325f | 2665 | /* Read the remote channel number from the message. */ |
2666 | remch = packet_get_int(); | |
2667 | ||
aa3378df | 2668 | /* |
2669 | * Get a connection to the local authentication agent (this may again | |
2670 | * get forwarded). | |
2671 | */ | |
5260325f | 2672 | sock = ssh_get_authentication_socket(); |
2673 | ||
aa3378df | 2674 | /* |
2675 | * If we could not connect the agent, send an error message back to | |
2676 | * the server. This should never happen unless the agent dies, | |
2677 | * because authentication forwarding is only enabled if we have an | |
2678 | * agent. | |
2679 | */ | |
5260325f | 2680 | if (sock < 0) { |
2681 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2682 | packet_put_int(remch); | |
2683 | packet_send(); | |
2684 | return; | |
2685 | } | |
2686 | debug("Forwarding authentication connection."); | |
2687 | ||
aa3378df | 2688 | /* |
2689 | * Dummy host name. This will be freed when the channel is freed; it | |
2690 | * will still be valid in the packet_put_string below since the | |
2691 | * channel cannot yet be freed at that point. | |
2692 | */ | |
5260325f | 2693 | dummyname = xstrdup("authentication agent connection"); |
2694 | ||
2695 | newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname); | |
2696 | channels[newch].remote_id = remch; | |
2697 | ||
2698 | /* Send a confirmation to the remote host. */ | |
2699 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2700 | packet_put_int(remch); | |
2701 | packet_put_int(newch); | |
2702 | packet_send(); | |
8efc0c15 | 2703 | } |
7e7327a1 | 2704 | |
2705 | void | |
0b242b12 | 2706 | channel_start_open(int id) |
7e7327a1 | 2707 | { |
2708 | Channel *c = channel_lookup(id); | |
2709 | if (c == NULL) { | |
2710 | log("channel_open: %d: bad id", id); | |
2711 | return; | |
2712 | } | |
0b242b12 | 2713 | debug("send channel open %d", id); |
7e7327a1 | 2714 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
2715 | packet_put_cstring(c->ctype); | |
2716 | packet_put_int(c->self); | |
2717 | packet_put_int(c->local_window); | |
2718 | packet_put_int(c->local_maxpacket); | |
0b242b12 | 2719 | } |
2720 | void | |
2721 | channel_open(int id) | |
2722 | { | |
2723 | /* XXX REMOVE ME */ | |
2724 | channel_start_open(id); | |
7e7327a1 | 2725 | packet_send(); |
7e7327a1 | 2726 | } |
2727 | void | |
2728 | channel_request(int id, char *service, int wantconfirm) | |
2729 | { | |
2730 | channel_request_start(id, service, wantconfirm); | |
2731 | packet_send(); | |
2732 | debug("channel request %d: %s", id, service) ; | |
2733 | } | |
2734 | void | |
2735 | channel_request_start(int id, char *service, int wantconfirm) | |
2736 | { | |
2737 | Channel *c = channel_lookup(id); | |
2738 | if (c == NULL) { | |
2739 | log("channel_request: %d: bad id", id); | |
2740 | return; | |
2741 | } | |
2742 | packet_start(SSH2_MSG_CHANNEL_REQUEST); | |
2743 | packet_put_int(c->remote_id); | |
2744 | packet_put_cstring(service); | |
2745 | packet_put_char(wantconfirm); | |
2746 | } | |
2747 | void | |
2748 | channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) | |
2749 | { | |
2750 | Channel *c = channel_lookup(id); | |
2751 | if (c == NULL) { | |
2752 | log("channel_register_callback: %d: bad id", id); | |
2753 | return; | |
2754 | } | |
2755 | c->cb_event = mtype; | |
2756 | c->cb_fn = fn; | |
2757 | c->cb_arg = arg; | |
2758 | } | |
2759 | void | |
2760 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
2761 | { | |
2762 | Channel *c = channel_lookup(id); | |
2763 | if (c == NULL) { | |
2764 | log("channel_register_cleanup: %d: bad id", id); | |
2765 | return; | |
2766 | } | |
2767 | c->dettach_user = fn; | |
2768 | } | |
2769 | void | |
2770 | channel_cancel_cleanup(int id) | |
2771 | { | |
2772 | Channel *c = channel_lookup(id); | |
2773 | if (c == NULL) { | |
2774 | log("channel_cancel_cleanup: %d: bad id", id); | |
2775 | return; | |
2776 | } | |
2777 | c->dettach_user = NULL; | |
2778 | } | |
2b87da3b | 2779 | void |
2e73a022 | 2780 | channel_register_filter(int id, channel_filter_fn *fn) |
2781 | { | |
2782 | Channel *c = channel_lookup(id); | |
2783 | if (c == NULL) { | |
2784 | log("channel_register_filter: %d: bad id", id); | |
2785 | return; | |
2786 | } | |
2787 | c->input_filter = fn; | |
2788 | } | |
7e7327a1 | 2789 | |
2790 | void | |
a22aff1f | 2791 | channel_set_fds(int id, int rfd, int wfd, int efd, |
2792 | int extusage, int nonblock) | |
7e7327a1 | 2793 | { |
2794 | Channel *c = channel_lookup(id); | |
2795 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) | |
2796 | fatal("channel_activate for non-larval channel %d.", id); | |
a22aff1f | 2797 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock); |
7e7327a1 | 2798 | c->type = SSH_CHANNEL_OPEN; |
7e7327a1 | 2799 | /* XXX window size? */ |
bcbf86ec | 2800 | c->local_window = c->local_window_max = c->local_maxpacket * 2; |
7e7327a1 | 2801 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
2802 | packet_put_int(c->remote_id); | |
2803 | packet_put_int(c->local_window); | |
2804 | packet_send(); | |
2805 | } |