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8efc0c15 | 1 | /* |
6ae2364d | 2 | * |
5260325f | 3 | * channels.c |
6ae2364d | 4 | * |
5260325f | 5 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
6ae2364d | 6 | * |
5260325f | 7 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
8 | * All rights reserved | |
6ae2364d | 9 | * |
5260325f | 10 | * Created: Fri Mar 24 16:35:24 1995 ylo |
6ae2364d | 11 | * |
5260325f | 12 | * This file contains functions for generic socket connection forwarding. |
13 | * There is also code for initiating connection forwarding for X11 connections, | |
14 | * arbitrary tcp/ip connections, and the authentication agent connection. | |
6ae2364d | 15 | * |
7e7327a1 | 16 | * SSH2 support added by Markus Friedl. |
5260325f | 17 | */ |
8efc0c15 | 18 | |
19 | #include "includes.h" | |
20 | RCSID("$Id$"); | |
21 | ||
22 | #include "ssh.h" | |
23 | #include "packet.h" | |
24 | #include "xmalloc.h" | |
25 | #include "buffer.h" | |
26 | #include "authfd.h" | |
27 | #include "uidswap.h" | |
6fa724bc | 28 | #include "readconf.h" |
8efc0c15 | 29 | #include "servconf.h" |
30 | ||
31 | #include "channels.h" | |
32 | #include "nchan.h" | |
33 | #include "compat.h" | |
34 | ||
7e7327a1 | 35 | #include "ssh2.h" |
36 | ||
8efc0c15 | 37 | /* Maximum number of fake X11 displays to try. */ |
38 | #define MAX_DISPLAYS 1000 | |
39 | ||
40 | /* Max len of agent socket */ | |
41 | #define MAX_SOCKET_NAME 100 | |
42 | ||
0b242b12 | 43 | /* default window/packet sizes for tcp/x11-fwd-channel */ |
44 | #define CHAN_TCP_WINDOW_DEFAULT (8*1024) | |
45 | #define CHAN_TCP_PACKET_DEFAULT (CHAN_TCP_WINDOW_DEFAULT/2) | |
46 | #define CHAN_X11_WINDOW_DEFAULT (4*1024) | |
47 | #define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2) | |
7368a6c8 | 48 | |
aa3378df | 49 | /* |
50 | * Pointer to an array containing all allocated channels. The array is | |
51 | * dynamically extended as needed. | |
52 | */ | |
8efc0c15 | 53 | static Channel *channels = NULL; |
54 | ||
aa3378df | 55 | /* |
56 | * Size of the channel array. All slots of the array must always be | |
57 | * initialized (at least the type field); unused slots are marked with type | |
58 | * SSH_CHANNEL_FREE. | |
59 | */ | |
8efc0c15 | 60 | static int channels_alloc = 0; |
61 | ||
aa3378df | 62 | /* |
63 | * Maximum file descriptor value used in any of the channels. This is | |
64 | * updated in channel_allocate. | |
65 | */ | |
8efc0c15 | 66 | static int channel_max_fd_value = 0; |
67 | ||
68 | /* Name and directory of socket for authentication agent forwarding. */ | |
69 | static char *channel_forwarded_auth_socket_name = NULL; | |
5260325f | 70 | static char *channel_forwarded_auth_socket_dir = NULL; |
8efc0c15 | 71 | |
72 | /* Saved X11 authentication protocol name. */ | |
73 | char *x11_saved_proto = NULL; | |
74 | ||
75 | /* Saved X11 authentication data. This is the real data. */ | |
76 | char *x11_saved_data = NULL; | |
77 | unsigned int x11_saved_data_len = 0; | |
78 | ||
aa3378df | 79 | /* |
80 | * Fake X11 authentication data. This is what the server will be sending us; | |
81 | * we should replace any occurrences of this by the real data. | |
82 | */ | |
8efc0c15 | 83 | char *x11_fake_data = NULL; |
84 | unsigned int x11_fake_data_len; | |
85 | ||
aa3378df | 86 | /* |
87 | * Data structure for storing which hosts are permitted for forward requests. | |
88 | * The local sides of any remote forwards are stored in this array to prevent | |
89 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
90 | * network (which might be behind a firewall). | |
91 | */ | |
5260325f | 92 | typedef struct { |
7368a6c8 | 93 | char *host_to_connect; /* Connect to 'host'. */ |
94 | u_short port_to_connect; /* Connect to 'port'. */ | |
95 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 96 | } ForwardPermission; |
97 | ||
98 | /* List of all permitted host/port pairs to connect. */ | |
99 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
100 | /* Number of permitted host/port pairs in the array. */ | |
101 | static int num_permitted_opens = 0; | |
aa3378df | 102 | /* |
103 | * If this is true, all opens are permitted. This is the case on the server | |
104 | * on which we have to trust the client anyway, and the user could do | |
105 | * anything after logging in anyway. | |
106 | */ | |
8efc0c15 | 107 | static int all_opens_permitted = 0; |
108 | ||
109 | /* This is set to true if both sides support SSH_PROTOFLAG_HOST_IN_FWD_OPEN. */ | |
110 | static int have_hostname_in_open = 0; | |
111 | ||
112 | /* Sets specific protocol options. */ | |
113 | ||
6ae2364d | 114 | void |
5260325f | 115 | channel_set_options(int hostname_in_open) |
8efc0c15 | 116 | { |
5260325f | 117 | have_hostname_in_open = hostname_in_open; |
8efc0c15 | 118 | } |
119 | ||
aa3378df | 120 | /* |
121 | * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually | |
122 | * called by the server, because the user could connect to any port anyway, | |
123 | * and the server has no way to know but to trust the client anyway. | |
124 | */ | |
8efc0c15 | 125 | |
6ae2364d | 126 | void |
5260325f | 127 | channel_permit_all_opens() |
8efc0c15 | 128 | { |
5260325f | 129 | all_opens_permitted = 1; |
8efc0c15 | 130 | } |
131 | ||
7368a6c8 | 132 | /* lookup channel by id */ |
133 | ||
134 | Channel * | |
135 | channel_lookup(int id) | |
136 | { | |
137 | Channel *c; | |
138 | if (id < 0 && id > channels_alloc) { | |
139 | log("channel_lookup: %d: bad id", id); | |
140 | return NULL; | |
141 | } | |
142 | c = &channels[id]; | |
143 | if (c->type == SSH_CHANNEL_FREE) { | |
144 | log("channel_lookup: %d: bad id: channel free", id); | |
145 | return NULL; | |
146 | } | |
147 | return c; | |
148 | } | |
149 | ||
aa3378df | 150 | /* |
1d1ffb87 | 151 | * Register filedescriptors for a channel, used when allocating a channel or |
0fbe8c74 | 152 | * when the channel consumer/producer is ready, e.g. shell exec'd |
aa3378df | 153 | */ |
8efc0c15 | 154 | |
0fbe8c74 | 155 | void |
156 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, int extusage) | |
8efc0c15 | 157 | { |
5260325f | 158 | /* Update the maximum file descriptor value. */ |
7368a6c8 | 159 | if (rfd > channel_max_fd_value) |
160 | channel_max_fd_value = rfd; | |
161 | if (wfd > channel_max_fd_value) | |
162 | channel_max_fd_value = wfd; | |
163 | if (efd > channel_max_fd_value) | |
164 | channel_max_fd_value = efd; | |
aa3378df | 165 | /* XXX set close-on-exec -markus */ |
1d1ffb87 | 166 | |
0fbe8c74 | 167 | c->rfd = rfd; |
168 | c->wfd = wfd; | |
169 | c->sock = (rfd == wfd) ? rfd : -1; | |
170 | c->efd = efd; | |
171 | c->extended_usage = extusage; | |
1d1ffb87 | 172 | if (rfd != -1) |
173 | set_nonblock(rfd); | |
174 | if (wfd != -1) | |
175 | set_nonblock(wfd); | |
176 | if (efd != -1) | |
177 | set_nonblock(efd); | |
0fbe8c74 | 178 | } |
179 | ||
180 | /* | |
181 | * Allocate a new channel object and set its type and socket. This will cause | |
182 | * remote_name to be freed. | |
183 | */ | |
184 | ||
185 | int | |
186 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, | |
187 | int window, int maxpack, int extusage, char *remote_name) | |
188 | { | |
189 | int i, found; | |
190 | Channel *c; | |
5260325f | 191 | |
192 | /* Do initial allocation if this is the first call. */ | |
193 | if (channels_alloc == 0) { | |
7e7327a1 | 194 | chan_init(); |
5260325f | 195 | channels_alloc = 10; |
196 | channels = xmalloc(channels_alloc * sizeof(Channel)); | |
197 | for (i = 0; i < channels_alloc; i++) | |
198 | channels[i].type = SSH_CHANNEL_FREE; | |
aa3378df | 199 | /* |
200 | * Kludge: arrange a call to channel_stop_listening if we | |
201 | * terminate with fatal(). | |
202 | */ | |
5260325f | 203 | fatal_add_cleanup((void (*) (void *)) channel_stop_listening, NULL); |
204 | } | |
205 | /* Try to find a free slot where to put the new channel. */ | |
206 | for (found = -1, i = 0; i < channels_alloc; i++) | |
207 | if (channels[i].type == SSH_CHANNEL_FREE) { | |
208 | /* Found a free slot. */ | |
209 | found = i; | |
210 | break; | |
211 | } | |
212 | if (found == -1) { | |
aa3378df | 213 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 214 | found = channels_alloc; |
215 | channels_alloc += 10; | |
216 | debug("channel: expanding %d", channels_alloc); | |
217 | channels = xrealloc(channels, channels_alloc * sizeof(Channel)); | |
218 | for (i = found; i < channels_alloc; i++) | |
219 | channels[i].type = SSH_CHANNEL_FREE; | |
220 | } | |
221 | /* Initialize and return new channel number. */ | |
222 | c = &channels[found]; | |
223 | buffer_init(&c->input); | |
224 | buffer_init(&c->output); | |
7368a6c8 | 225 | buffer_init(&c->extended); |
5260325f | 226 | chan_init_iostates(c); |
0fbe8c74 | 227 | channel_register_fds(c, rfd, wfd, efd, extusage); |
5260325f | 228 | c->self = found; |
229 | c->type = type; | |
7368a6c8 | 230 | c->ctype = ctype; |
0b242b12 | 231 | c->local_window = window; |
232 | c->local_window_max = window; | |
233 | c->local_consumed = 0; | |
234 | c->local_maxpacket = maxpack; | |
5260325f | 235 | c->remote_id = -1; |
236 | c->remote_name = remote_name; | |
7368a6c8 | 237 | c->remote_window = 0; |
238 | c->remote_maxpacket = 0; | |
239 | c->cb_fn = NULL; | |
240 | c->cb_arg = NULL; | |
241 | c->cb_event = 0; | |
242 | c->dettach_user = NULL; | |
5260325f | 243 | debug("channel %d: new [%s]", found, remote_name); |
244 | return found; | |
8efc0c15 | 245 | } |
0fbe8c74 | 246 | /* old interface XXX */ |
6ae2364d | 247 | int |
7368a6c8 | 248 | channel_allocate(int type, int sock, char *remote_name) |
249 | { | |
250 | return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name); | |
251 | } | |
8efc0c15 | 252 | |
0fbe8c74 | 253 | |
254 | /* Close all channel fd/socket. */ | |
255 | ||
256 | void | |
257 | channel_close_fds(Channel *c) | |
258 | { | |
259 | if (c->sock != -1) { | |
260 | close(c->sock); | |
261 | c->sock = -1; | |
262 | } | |
263 | if (c->rfd != -1) { | |
264 | close(c->rfd); | |
265 | c->rfd = -1; | |
266 | } | |
267 | if (c->wfd != -1) { | |
268 | close(c->wfd); | |
269 | c->wfd = -1; | |
270 | } | |
271 | if (c->efd != -1) { | |
272 | close(c->efd); | |
273 | c->efd = -1; | |
274 | } | |
275 | } | |
276 | ||
277 | /* Free the channel and close its fd/socket. */ | |
8efc0c15 | 278 | |
6ae2364d | 279 | void |
7368a6c8 | 280 | channel_free(int id) |
8efc0c15 | 281 | { |
7368a6c8 | 282 | Channel *c = channel_lookup(id); |
283 | if (c == NULL) | |
284 | packet_disconnect("channel free: bad local channel %d", id); | |
285 | debug("channel_free: channel %d: status: %s", id, channel_open_message()); | |
7e7327a1 | 286 | if (c->dettach_user != NULL) { |
287 | debug("channel_free: channel %d: dettaching channel user", id); | |
288 | c->dettach_user(c->self, NULL); | |
289 | } | |
0fbe8c74 | 290 | if (c->sock != -1) |
7368a6c8 | 291 | shutdown(c->sock, SHUT_RDWR); |
0fbe8c74 | 292 | channel_close_fds(c); |
7368a6c8 | 293 | buffer_free(&c->input); |
294 | buffer_free(&c->output); | |
295 | buffer_free(&c->extended); | |
296 | c->type = SSH_CHANNEL_FREE; | |
297 | if (c->remote_name) { | |
298 | xfree(c->remote_name); | |
299 | c->remote_name = NULL; | |
5260325f | 300 | } |
8efc0c15 | 301 | } |
302 | ||
aa3378df | 303 | /* |
7368a6c8 | 304 | * 'channel_pre*' are called just before select() to add any bits relevant to |
305 | * channels in the select bitmasks. | |
aa3378df | 306 | */ |
7368a6c8 | 307 | /* |
308 | * 'channel_post*': perform any appropriate operations for channels which | |
309 | * have events pending. | |
310 | */ | |
311 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
312 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
313 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 314 | |
7368a6c8 | 315 | void |
316 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
8efc0c15 | 317 | { |
7368a6c8 | 318 | FD_SET(c->sock, readset); |
319 | } | |
5260325f | 320 | |
7368a6c8 | 321 | void |
322 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) | |
323 | { | |
324 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
325 | FD_SET(c->sock, readset); | |
326 | if (buffer_len(&c->output) > 0) | |
327 | FD_SET(c->sock, writeset); | |
328 | } | |
5260325f | 329 | |
7368a6c8 | 330 | void |
331 | channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset) | |
332 | { | |
333 | /* test whether sockets are 'alive' for read/write */ | |
334 | if (c->istate == CHAN_INPUT_OPEN) | |
335 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
336 | FD_SET(c->sock, readset); | |
337 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
338 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
339 | if (buffer_len(&c->output) > 0) { | |
340 | FD_SET(c->sock, writeset); | |
341 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
342 | chan_obuf_empty(c); | |
343 | } | |
344 | } | |
345 | } | |
5260325f | 346 | |
7e7327a1 | 347 | void |
348 | channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset) | |
349 | { | |
350 | if (c->istate == CHAN_INPUT_OPEN && | |
351 | c->remote_window > 0 && | |
352 | buffer_len(&c->input) < c->remote_window) | |
353 | FD_SET(c->rfd, readset); | |
354 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
355 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
356 | if (buffer_len(&c->output) > 0) { | |
357 | FD_SET(c->wfd, writeset); | |
358 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
359 | chan_obuf_empty(c); | |
360 | } | |
361 | } | |
362 | /** XXX check close conditions, too */ | |
363 | if (c->efd != -1) { | |
364 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
365 | buffer_len(&c->extended) > 0) | |
366 | FD_SET(c->efd, writeset); | |
367 | else if (c->extended_usage == CHAN_EXTENDED_READ && | |
368 | buffer_len(&c->extended) < c->remote_window) | |
369 | FD_SET(c->efd, readset); | |
370 | } | |
371 | } | |
372 | ||
7368a6c8 | 373 | void |
374 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) | |
375 | { | |
376 | if (buffer_len(&c->input) == 0) { | |
377 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
378 | packet_put_int(c->remote_id); | |
379 | packet_send(); | |
380 | c->type = SSH_CHANNEL_CLOSED; | |
381 | debug("Closing channel %d after input drain.", c->self); | |
382 | } | |
383 | } | |
5260325f | 384 | |
7368a6c8 | 385 | void |
386 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) | |
387 | { | |
388 | if (buffer_len(&c->output) == 0) | |
389 | channel_free(c->self); | |
6ae2364d | 390 | else |
7368a6c8 | 391 | FD_SET(c->sock, writeset); |
392 | } | |
5260325f | 393 | |
7368a6c8 | 394 | /* |
395 | * This is a special state for X11 authentication spoofing. An opened X11 | |
396 | * connection (when authentication spoofing is being done) remains in this | |
397 | * state until the first packet has been completely read. The authentication | |
398 | * data in that packet is then substituted by the real data if it matches the | |
399 | * fake data, and the channel is put into normal mode. | |
0b242b12 | 400 | * XXX All this happens at the client side. |
7368a6c8 | 401 | */ |
402 | int | |
403 | x11_open_helper(Channel *c) | |
404 | { | |
405 | unsigned char *ucp; | |
406 | unsigned int proto_len, data_len; | |
5260325f | 407 | |
7368a6c8 | 408 | /* Check if the fixed size part of the packet is in buffer. */ |
409 | if (buffer_len(&c->output) < 12) | |
410 | return 0; | |
411 | ||
412 | /* Parse the lengths of variable-length fields. */ | |
413 | ucp = (unsigned char *) buffer_ptr(&c->output); | |
414 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ | |
415 | proto_len = 256 * ucp[6] + ucp[7]; | |
416 | data_len = 256 * ucp[8] + ucp[9]; | |
417 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
418 | proto_len = ucp[6] + 256 * ucp[7]; | |
419 | data_len = ucp[8] + 256 * ucp[9]; | |
420 | } else { | |
421 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
422 | ucp[0]); | |
423 | return -1; | |
424 | } | |
5260325f | 425 | |
7368a6c8 | 426 | /* Check if the whole packet is in buffer. */ |
427 | if (buffer_len(&c->output) < | |
428 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) | |
429 | return 0; | |
5260325f | 430 | |
7368a6c8 | 431 | /* Check if authentication protocol matches. */ |
432 | if (proto_len != strlen(x11_saved_proto) || | |
433 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
434 | debug("X11 connection uses different authentication protocol."); | |
435 | return -1; | |
436 | } | |
437 | /* Check if authentication data matches our fake data. */ | |
438 | if (data_len != x11_fake_data_len || | |
439 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
440 | x11_fake_data, x11_fake_data_len) != 0) { | |
441 | debug("X11 auth data does not match fake data."); | |
442 | return -1; | |
443 | } | |
444 | /* Check fake data length */ | |
445 | if (x11_fake_data_len != x11_saved_data_len) { | |
446 | error("X11 fake_data_len %d != saved_data_len %d", | |
447 | x11_fake_data_len, x11_saved_data_len); | |
448 | return -1; | |
449 | } | |
450 | /* | |
451 | * Received authentication protocol and data match | |
452 | * our fake data. Substitute the fake data with real | |
453 | * data. | |
454 | */ | |
455 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
456 | x11_saved_data, x11_saved_data_len); | |
457 | return 1; | |
458 | } | |
5260325f | 459 | |
7368a6c8 | 460 | void |
461 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) | |
462 | { | |
463 | int ret = x11_open_helper(c); | |
464 | if (ret == 1) { | |
465 | /* Start normal processing for the channel. */ | |
466 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 467 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 468 | } else if (ret == -1) { |
469 | /* | |
470 | * We have received an X11 connection that has bad | |
471 | * authentication information. | |
472 | */ | |
473 | log("X11 connection rejected because of wrong authentication.\r\n"); | |
474 | buffer_clear(&c->input); | |
475 | buffer_clear(&c->output); | |
476 | close(c->sock); | |
477 | c->sock = -1; | |
478 | c->type = SSH_CHANNEL_CLOSED; | |
479 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
480 | packet_put_int(c->remote_id); | |
481 | packet_send(); | |
482 | } | |
483 | } | |
5260325f | 484 | |
7368a6c8 | 485 | void |
0b242b12 | 486 | channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset) |
7368a6c8 | 487 | { |
488 | int ret = x11_open_helper(c); | |
489 | if (ret == 1) { | |
490 | c->type = SSH_CHANNEL_OPEN; | |
d0c832f3 | 491 | if (compat20) |
492 | channel_pre_open_20(c, readset, writeset); | |
493 | else | |
494 | channel_pre_open_15(c, readset, writeset); | |
7368a6c8 | 495 | } else if (ret == -1) { |
496 | debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); | |
0b242b12 | 497 | chan_read_failed(c); /** force close? */ |
7368a6c8 | 498 | chan_write_failed(c); |
499 | debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); | |
500 | } | |
501 | } | |
5260325f | 502 | |
7368a6c8 | 503 | /* This is our fake X11 server socket. */ |
504 | void | |
505 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
506 | { | |
507 | struct sockaddr addr; | |
508 | int newsock, newch; | |
509 | socklen_t addrlen; | |
510 | char buf[16384], *remote_hostname; | |
0b242b12 | 511 | int remote_port; |
7368a6c8 | 512 | |
513 | if (FD_ISSET(c->sock, readset)) { | |
514 | debug("X11 connection requested."); | |
515 | addrlen = sizeof(addr); | |
516 | newsock = accept(c->sock, &addr, &addrlen); | |
517 | if (newsock < 0) { | |
518 | error("accept: %.100s", strerror(errno)); | |
519 | return; | |
5260325f | 520 | } |
7368a6c8 | 521 | remote_hostname = get_remote_hostname(newsock); |
0b242b12 | 522 | remote_port = get_peer_port(newsock); |
7368a6c8 | 523 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
0b242b12 | 524 | remote_hostname, remote_port); |
525 | ||
526 | newch = channel_new("x11", | |
527 | SSH_CHANNEL_OPENING, newsock, newsock, -1, | |
528 | c->local_window_max, c->local_maxpacket, | |
529 | 0, xstrdup(buf)); | |
530 | if (compat20) { | |
531 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
532 | packet_put_cstring("x11"); | |
533 | packet_put_int(newch); | |
534 | packet_put_int(c->local_window_max); | |
535 | packet_put_int(c->local_maxpacket); | |
536 | /* originator host and port */ | |
537 | packet_put_cstring(remote_hostname); | |
d0c832f3 | 538 | if (datafellows & SSH_BUG_X11FWD) { |
539 | debug("ssh2 x11 bug compat mode"); | |
540 | } else { | |
541 | packet_put_int(remote_port); | |
542 | } | |
0b242b12 | 543 | packet_send(); |
544 | } else { | |
545 | packet_start(SSH_SMSG_X11_OPEN); | |
546 | packet_put_int(newch); | |
547 | if (have_hostname_in_open) | |
548 | packet_put_string(buf, strlen(buf)); | |
549 | packet_send(); | |
550 | } | |
7368a6c8 | 551 | xfree(remote_hostname); |
8efc0c15 | 552 | } |
8efc0c15 | 553 | } |
554 | ||
aa3378df | 555 | /* |
7368a6c8 | 556 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 557 | */ |
7368a6c8 | 558 | void |
559 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
560 | { | |
561 | struct sockaddr addr; | |
562 | int newsock, newch; | |
563 | socklen_t addrlen; | |
564 | char buf[1024], *remote_hostname; | |
565 | int remote_port; | |
566 | ||
567 | if (FD_ISSET(c->sock, readset)) { | |
568 | debug("Connection to port %d forwarding " | |
569 | "to %.100s port %d requested.", | |
570 | c->listening_port, c->path, c->host_port); | |
571 | addrlen = sizeof(addr); | |
572 | newsock = accept(c->sock, &addr, &addrlen); | |
573 | if (newsock < 0) { | |
574 | error("accept: %.100s", strerror(errno)); | |
575 | return; | |
576 | } | |
577 | remote_hostname = get_remote_hostname(newsock); | |
578 | remote_port = get_peer_port(newsock); | |
579 | snprintf(buf, sizeof buf, | |
580 | "listen port %d for %.100s port %d, " | |
581 | "connect from %.200s port %d", | |
582 | c->listening_port, c->path, c->host_port, | |
583 | remote_hostname, remote_port); | |
584 | newch = channel_new("direct-tcpip", | |
585 | SSH_CHANNEL_OPENING, newsock, newsock, -1, | |
586 | c->local_window_max, c->local_maxpacket, | |
587 | 0, xstrdup(buf)); | |
7e7327a1 | 588 | if (compat20) { |
589 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
590 | packet_put_cstring("direct-tcpip"); | |
591 | packet_put_int(newch); | |
592 | packet_put_int(c->local_window_max); | |
593 | packet_put_int(c->local_maxpacket); | |
6ae2364d | 594 | /* target host and port */ |
7e7327a1 | 595 | packet_put_string(c->path, strlen(c->path)); |
596 | packet_put_int(c->host_port); | |
6ae2364d | 597 | /* originator host and port */ |
7e7327a1 | 598 | packet_put_cstring(remote_hostname); |
599 | packet_put_int(remote_port); | |
600 | packet_send(); | |
601 | } else { | |
602 | packet_start(SSH_MSG_PORT_OPEN); | |
603 | packet_put_int(newch); | |
604 | packet_put_string(c->path, strlen(c->path)); | |
605 | packet_put_int(c->host_port); | |
606 | if (have_hostname_in_open) { | |
607 | packet_put_string(buf, strlen(buf)); | |
608 | } | |
609 | packet_send(); | |
7368a6c8 | 610 | } |
7368a6c8 | 611 | xfree(remote_hostname); |
612 | } | |
613 | } | |
8efc0c15 | 614 | |
7368a6c8 | 615 | /* |
616 | * This is the authentication agent socket listening for connections from | |
617 | * clients. | |
618 | */ | |
619 | void | |
620 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
8efc0c15 | 621 | { |
5260325f | 622 | struct sockaddr addr; |
7368a6c8 | 623 | int newsock, newch; |
48e671d5 | 624 | socklen_t addrlen; |
5260325f | 625 | |
7368a6c8 | 626 | if (FD_ISSET(c->sock, readset)) { |
627 | addrlen = sizeof(addr); | |
628 | newsock = accept(c->sock, &addr, &addrlen); | |
629 | if (newsock < 0) { | |
630 | error("accept from auth socket: %.100s", strerror(errno)); | |
631 | return; | |
632 | } | |
633 | newch = channel_allocate(SSH_CHANNEL_OPENING, newsock, | |
634 | xstrdup("accepted auth socket")); | |
635 | packet_start(SSH_SMSG_AGENT_OPEN); | |
636 | packet_put_int(newch); | |
637 | packet_send(); | |
638 | } | |
639 | } | |
5260325f | 640 | |
7368a6c8 | 641 | int |
642 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) | |
643 | { | |
644 | char buf[16*1024]; | |
645 | int len; | |
646 | ||
647 | if (c->rfd != -1 && | |
648 | FD_ISSET(c->rfd, readset)) { | |
649 | len = read(c->rfd, buf, sizeof(buf)); | |
0fbe8c74 | 650 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
651 | return 1; | |
7368a6c8 | 652 | if (len <= 0) { |
0b242b12 | 653 | debug("channel %d: read<=0 rfd %d len %d", |
7368a6c8 | 654 | c->self, c->rfd, len); |
655 | if (compat13) { | |
656 | buffer_consume(&c->output, buffer_len(&c->output)); | |
657 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
658 | debug("Channel %d status set to input draining.", c->self); | |
659 | } else { | |
660 | chan_read_failed(c); | |
5260325f | 661 | } |
7368a6c8 | 662 | return -1; |
663 | } | |
664 | buffer_append(&c->input, buf, len); | |
665 | } | |
666 | return 1; | |
667 | } | |
668 | int | |
669 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) | |
670 | { | |
671 | int len; | |
672 | ||
673 | /* Send buffered output data to the socket. */ | |
674 | if (c->wfd != -1 && | |
675 | FD_ISSET(c->wfd, writeset) && | |
676 | buffer_len(&c->output) > 0) { | |
677 | len = write(c->wfd, buffer_ptr(&c->output), | |
0fbe8c74 | 678 | buffer_len(&c->output)); |
679 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) | |
680 | return 1; | |
7368a6c8 | 681 | if (len <= 0) { |
682 | if (compat13) { | |
683 | buffer_consume(&c->output, buffer_len(&c->output)); | |
684 | debug("Channel %d status set to input draining.", c->self); | |
685 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
686 | } else { | |
687 | chan_write_failed(c); | |
5260325f | 688 | } |
7368a6c8 | 689 | return -1; |
690 | } | |
691 | buffer_consume(&c->output, len); | |
7e7327a1 | 692 | if (compat20 && len > 0) { |
693 | c->local_consumed += len; | |
694 | } | |
695 | } | |
696 | return 1; | |
697 | } | |
698 | int | |
699 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) | |
700 | { | |
701 | char buf[16*1024]; | |
702 | int len; | |
703 | ||
8ce64345 | 704 | /** XXX handle drain efd, too */ |
7e7327a1 | 705 | if (c->efd != -1) { |
706 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
707 | FD_ISSET(c->efd, writeset) && | |
708 | buffer_len(&c->extended) > 0) { | |
709 | len = write(c->efd, buffer_ptr(&c->extended), | |
710 | buffer_len(&c->extended)); | |
711 | debug("channel %d: written %d to efd %d", | |
712 | c->self, len, c->efd); | |
713 | if (len > 0) { | |
714 | buffer_consume(&c->extended, len); | |
715 | c->local_consumed += len; | |
716 | } | |
717 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
718 | FD_ISSET(c->efd, readset)) { | |
719 | len = read(c->efd, buf, sizeof(buf)); | |
720 | debug("channel %d: read %d from efd %d", | |
721 | c->self, len, c->efd); | |
8ce64345 | 722 | if (len == 0) { |
723 | debug("channel %d: closing efd %d", | |
724 | c->self, c->efd); | |
725 | close(c->efd); | |
726 | c->efd = -1; | |
727 | } else if (len > 0) | |
7e7327a1 | 728 | buffer_append(&c->extended, buf, len); |
729 | } | |
730 | } | |
731 | return 1; | |
732 | } | |
733 | int | |
734 | channel_check_window(Channel *c, fd_set * readset, fd_set * writeset) | |
735 | { | |
e78a59f5 | 736 | if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && |
7e7327a1 | 737 | c->local_window < c->local_window_max/2 && |
738 | c->local_consumed > 0) { | |
739 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
740 | packet_put_int(c->remote_id); | |
741 | packet_put_int(c->local_consumed); | |
742 | packet_send(); | |
743 | debug("channel %d: window %d sent adjust %d", | |
744 | c->self, c->local_window, | |
745 | c->local_consumed); | |
746 | c->local_window += c->local_consumed; | |
747 | c->local_consumed = 0; | |
7368a6c8 | 748 | } |
749 | return 1; | |
750 | } | |
5260325f | 751 | |
7368a6c8 | 752 | void |
753 | channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset) | |
754 | { | |
755 | channel_handle_rfd(c, readset, writeset); | |
756 | channel_handle_wfd(c, readset, writeset); | |
757 | } | |
aa3378df | 758 | |
7e7327a1 | 759 | void |
760 | channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset) | |
761 | { | |
762 | channel_handle_rfd(c, readset, writeset); | |
763 | channel_handle_wfd(c, readset, writeset); | |
764 | channel_handle_efd(c, readset, writeset); | |
765 | channel_check_window(c, readset, writeset); | |
766 | } | |
767 | ||
7368a6c8 | 768 | void |
769 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) | |
770 | { | |
771 | int len; | |
772 | /* Send buffered output data to the socket. */ | |
773 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
774 | len = write(c->sock, buffer_ptr(&c->output), | |
775 | buffer_len(&c->output)); | |
776 | if (len <= 0) | |
777 | buffer_consume(&c->output, buffer_len(&c->output)); | |
778 | else | |
779 | buffer_consume(&c->output, len); | |
780 | } | |
781 | } | |
5260325f | 782 | |
7e7327a1 | 783 | void |
784 | channel_handler_init_20(void) | |
785 | { | |
786 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20; | |
0b242b12 | 787 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7e7327a1 | 788 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
0b242b12 | 789 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
7e7327a1 | 790 | |
791 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2; | |
792 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
0b242b12 | 793 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
7e7327a1 | 794 | } |
795 | ||
7368a6c8 | 796 | void |
797 | channel_handler_init_13(void) | |
798 | { | |
799 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
800 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
801 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
802 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
803 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
804 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
805 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
806 | ||
807 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
808 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
809 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
810 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
811 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
812 | } | |
5260325f | 813 | |
7368a6c8 | 814 | void |
815 | channel_handler_init_15(void) | |
816 | { | |
817 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15; | |
0b242b12 | 818 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
7368a6c8 | 819 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
820 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
821 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
822 | ||
823 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
824 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
825 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
826 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
827 | } | |
828 | ||
829 | void | |
830 | channel_handler_init(void) | |
831 | { | |
832 | int i; | |
833 | for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { | |
834 | channel_pre[i] = NULL; | |
835 | channel_post[i] = NULL; | |
836 | } | |
7e7327a1 | 837 | if (compat20) |
838 | channel_handler_init_20(); | |
839 | else if (compat13) | |
7368a6c8 | 840 | channel_handler_init_13(); |
841 | else | |
842 | channel_handler_init_15(); | |
843 | } | |
844 | ||
6ae2364d | 845 | void |
7368a6c8 | 846 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) |
847 | { | |
848 | static int did_init = 0; | |
849 | int i; | |
850 | Channel *c; | |
851 | ||
852 | if (!did_init) { | |
853 | channel_handler_init(); | |
854 | did_init = 1; | |
855 | } | |
856 | for (i = 0; i < channels_alloc; i++) { | |
857 | c = &channels[i]; | |
858 | if (c->type == SSH_CHANNEL_FREE) | |
5260325f | 859 | continue; |
7368a6c8 | 860 | if (ftab[c->type] == NULL) |
861 | continue; | |
862 | (*ftab[c->type])(c, readset, writeset); | |
7e7327a1 | 863 | chan_delete_if_full_closed(c); |
8efc0c15 | 864 | } |
8efc0c15 | 865 | } |
866 | ||
6ae2364d | 867 | void |
7368a6c8 | 868 | channel_prepare_select(fd_set * readset, fd_set * writeset) |
869 | { | |
870 | channel_handler(channel_pre, readset, writeset); | |
871 | } | |
872 | ||
6ae2364d | 873 | void |
7368a6c8 | 874 | channel_after_select(fd_set * readset, fd_set * writeset) |
875 | { | |
876 | channel_handler(channel_post, readset, writeset); | |
877 | } | |
878 | ||
8efc0c15 | 879 | /* If there is data to send to the connection, send some of it now. */ |
880 | ||
6ae2364d | 881 | void |
5260325f | 882 | channel_output_poll() |
8efc0c15 | 883 | { |
5260325f | 884 | int len, i; |
7368a6c8 | 885 | Channel *c; |
5260325f | 886 | |
887 | for (i = 0; i < channels_alloc; i++) { | |
7368a6c8 | 888 | c = &channels[i]; |
48e671d5 | 889 | |
aa3378df | 890 | /* We are only interested in channels that can have buffered incoming data. */ |
48e671d5 | 891 | if (compat13) { |
7368a6c8 | 892 | if (c->type != SSH_CHANNEL_OPEN && |
893 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 894 | continue; |
895 | } else { | |
7368a6c8 | 896 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 897 | continue; |
7368a6c8 | 898 | if (c->istate != CHAN_INPUT_OPEN && |
899 | c->istate != CHAN_INPUT_WAIT_DRAIN) | |
48e671d5 | 900 | continue; |
901 | } | |
e78a59f5 | 902 | if (compat20 && |
903 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
7e7327a1 | 904 | debug("channel: %d: no data after CLOSE", c->self); |
905 | continue; | |
906 | } | |
5260325f | 907 | |
908 | /* Get the amount of buffered data for this channel. */ | |
7368a6c8 | 909 | len = buffer_len(&c->input); |
5260325f | 910 | if (len > 0) { |
aa3378df | 911 | /* Send some data for the other side over the secure connection. */ |
7e7327a1 | 912 | if (compat20) { |
913 | if (len > c->remote_window) | |
914 | len = c->remote_window; | |
915 | if (len > c->remote_maxpacket) | |
916 | len = c->remote_maxpacket; | |
5260325f | 917 | } else { |
7e7327a1 | 918 | if (packet_is_interactive()) { |
919 | if (len > 1024) | |
920 | len = 512; | |
921 | } else { | |
922 | /* Keep the packets at reasonable size. */ | |
923 | if (len > packet_get_maxsize()/2) | |
924 | len = packet_get_maxsize()/2; | |
925 | } | |
5260325f | 926 | } |
7368a6c8 | 927 | if (len > 0) { |
7e7327a1 | 928 | packet_start(compat20 ? |
929 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 930 | packet_put_int(c->remote_id); |
931 | packet_put_string(buffer_ptr(&c->input), len); | |
932 | packet_send(); | |
933 | buffer_consume(&c->input, len); | |
934 | c->remote_window -= len; | |
7e7327a1 | 935 | debug("channel %d: send data len %d", c->self, len); |
7368a6c8 | 936 | } |
937 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 938 | if (compat13) |
939 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 940 | /* |
941 | * input-buffer is empty and read-socket shutdown: | |
942 | * tell peer, that we will not send more data: send IEOF | |
943 | */ | |
7368a6c8 | 944 | chan_ibuf_empty(c); |
5260325f | 945 | } |
7e7327a1 | 946 | /* Send extended data, i.e. stderr */ |
947 | if (compat20 && | |
948 | c->remote_window > 0 && | |
949 | (len = buffer_len(&c->extended)) > 0 && | |
950 | c->extended_usage == CHAN_EXTENDED_READ) { | |
951 | if (len > c->remote_window) | |
952 | len = c->remote_window; | |
953 | if (len > c->remote_maxpacket) | |
954 | len = c->remote_maxpacket; | |
955 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
956 | packet_put_int(c->remote_id); | |
957 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
958 | packet_put_string(buffer_ptr(&c->extended), len); | |
959 | packet_send(); | |
960 | buffer_consume(&c->extended, len); | |
961 | c->remote_window -= len; | |
962 | } | |
8efc0c15 | 963 | } |
8efc0c15 | 964 | } |
965 | ||
aa3378df | 966 | /* |
967 | * This is called when a packet of type CHANNEL_DATA has just been received. | |
968 | * The message type has already been consumed, but channel number and data is | |
969 | * still there. | |
970 | */ | |
8efc0c15 | 971 | |
6ae2364d | 972 | void |
7368a6c8 | 973 | channel_input_data(int type, int plen) |
8efc0c15 | 974 | { |
48e671d5 | 975 | int id; |
5260325f | 976 | char *data; |
977 | unsigned int data_len; | |
7368a6c8 | 978 | Channel *c; |
5260325f | 979 | |
980 | /* Get the channel number and verify it. */ | |
48e671d5 | 981 | id = packet_get_int(); |
7368a6c8 | 982 | c = channel_lookup(id); |
983 | if (c == NULL) | |
48e671d5 | 984 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 985 | |
986 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 987 | if (c->type != SSH_CHANNEL_OPEN && |
988 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 989 | return; |
990 | ||
991 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 992 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 993 | return; |
994 | ||
995 | /* Get the data. */ | |
996 | data = packet_get_string(&data_len); | |
6ae2364d | 997 | packet_done(); |
7368a6c8 | 998 | |
7e7327a1 | 999 | if (compat20){ |
1000 | if (data_len > c->local_maxpacket) { | |
1001 | log("channel %d: rcvd big packet %d, maxpack %d", | |
1002 | c->self, data_len, c->local_maxpacket); | |
1003 | } | |
1004 | if (data_len > c->local_window) { | |
1005 | log("channel %d: rcvd too much data %d, win %d", | |
1006 | c->self, data_len, c->local_window); | |
1007 | xfree(data); | |
1008 | return; | |
1009 | } | |
1010 | c->local_window -= data_len; | |
1011 | }else{ | |
1012 | packet_integrity_check(plen, 4 + 4 + data_len, type); | |
1013 | } | |
7368a6c8 | 1014 | buffer_append(&c->output, data, data_len); |
5260325f | 1015 | xfree(data); |
8efc0c15 | 1016 | } |
6ae2364d | 1017 | void |
7e7327a1 | 1018 | channel_input_extended_data(int type, int plen) |
1019 | { | |
1020 | int id; | |
1021 | int tcode; | |
1022 | char *data; | |
1023 | unsigned int data_len; | |
1024 | Channel *c; | |
1025 | ||
1026 | /* Get the channel number and verify it. */ | |
1027 | id = packet_get_int(); | |
1028 | c = channel_lookup(id); | |
1029 | ||
1030 | if (c == NULL) | |
1031 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
1032 | if (c->type != SSH_CHANNEL_OPEN) { | |
1033 | log("channel %d: ext data for non open", id); | |
1034 | return; | |
1035 | } | |
1036 | tcode = packet_get_int(); | |
1037 | if (c->efd == -1 || | |
1038 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
1039 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
1040 | log("channel %d: bad ext data", c->self); | |
1041 | return; | |
1042 | } | |
1043 | data = packet_get_string(&data_len); | |
6ae2364d | 1044 | packet_done(); |
7e7327a1 | 1045 | if (data_len > c->local_window) { |
1046 | log("channel %d: rcvd too much extended_data %d, win %d", | |
1047 | c->self, data_len, c->local_window); | |
1048 | xfree(data); | |
1049 | return; | |
1050 | } | |
1051 | debug("channel %d: rcvd ext data %d", c->self, data_len); | |
1052 | c->local_window -= data_len; | |
1053 | buffer_append(&c->extended, data, data_len); | |
1054 | xfree(data); | |
1055 | } | |
1056 | ||
8efc0c15 | 1057 | |
aa3378df | 1058 | /* |
1059 | * Returns true if no channel has too much buffered data, and false if one or | |
1060 | * more channel is overfull. | |
1061 | */ | |
8efc0c15 | 1062 | |
6ae2364d | 1063 | int |
5260325f | 1064 | channel_not_very_much_buffered_data() |
8efc0c15 | 1065 | { |
5260325f | 1066 | unsigned int i; |
7368a6c8 | 1067 | Channel *c; |
5260325f | 1068 | |
1069 | for (i = 0; i < channels_alloc; i++) { | |
7368a6c8 | 1070 | c = &channels[i]; |
1071 | if (c->type == SSH_CHANNEL_OPEN) { | |
7e7327a1 | 1072 | if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { |
7368a6c8 | 1073 | debug("channel %d: big input buffer %d", |
1074 | c->self, buffer_len(&c->input)); | |
5260325f | 1075 | return 0; |
7368a6c8 | 1076 | } |
1077 | if (buffer_len(&c->output) > packet_get_maxsize()) { | |
1078 | debug("channel %d: big output buffer %d", | |
1079 | c->self, buffer_len(&c->output)); | |
5260325f | 1080 | return 0; |
7368a6c8 | 1081 | } |
5260325f | 1082 | } |
8efc0c15 | 1083 | } |
5260325f | 1084 | return 1; |
8efc0c15 | 1085 | } |
1086 | ||
6ae2364d | 1087 | void |
7368a6c8 | 1088 | channel_input_ieof(int type, int plen) |
1089 | { | |
1090 | int id; | |
1091 | Channel *c; | |
1092 | ||
1093 | packet_integrity_check(plen, 4, type); | |
1094 | ||
1095 | id = packet_get_int(); | |
1096 | c = channel_lookup(id); | |
1097 | if (c == NULL) | |
1098 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1099 | chan_rcvd_ieof(c); | |
1100 | } | |
8efc0c15 | 1101 | |
6ae2364d | 1102 | void |
7368a6c8 | 1103 | channel_input_close(int type, int plen) |
8efc0c15 | 1104 | { |
7368a6c8 | 1105 | int id; |
1106 | Channel *c; | |
5260325f | 1107 | |
7368a6c8 | 1108 | packet_integrity_check(plen, 4, type); |
1109 | ||
1110 | id = packet_get_int(); | |
1111 | c = channel_lookup(id); | |
1112 | if (c == NULL) | |
1113 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1114 | |
1115 | /* | |
1116 | * Send a confirmation that we have closed the channel and no more | |
1117 | * data is coming for it. | |
1118 | */ | |
5260325f | 1119 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1120 | packet_put_int(c->remote_id); |
5260325f | 1121 | packet_send(); |
1122 | ||
aa3378df | 1123 | /* |
1124 | * If the channel is in closed state, we have sent a close request, | |
1125 | * and the other side will eventually respond with a confirmation. | |
1126 | * Thus, we cannot free the channel here, because then there would be | |
1127 | * no-one to receive the confirmation. The channel gets freed when | |
1128 | * the confirmation arrives. | |
1129 | */ | |
7368a6c8 | 1130 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1131 | /* |
1132 | * Not a closed channel - mark it as draining, which will | |
1133 | * cause it to be freed later. | |
1134 | */ | |
7368a6c8 | 1135 | buffer_consume(&c->input, buffer_len(&c->input)); |
1136 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; | |
5260325f | 1137 | } |
8efc0c15 | 1138 | } |
1139 | ||
7368a6c8 | 1140 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
6ae2364d | 1141 | void |
7368a6c8 | 1142 | channel_input_oclose(int type, int plen) |
8efc0c15 | 1143 | { |
7368a6c8 | 1144 | int id = packet_get_int(); |
1145 | Channel *c = channel_lookup(id); | |
1146 | packet_integrity_check(plen, 4, type); | |
1147 | if (c == NULL) | |
1148 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1149 | chan_rcvd_oclose(c); | |
8efc0c15 | 1150 | } |
1151 | ||
6ae2364d | 1152 | void |
7368a6c8 | 1153 | channel_input_close_confirmation(int type, int plen) |
1154 | { | |
1155 | int id = packet_get_int(); | |
1156 | Channel *c = channel_lookup(id); | |
1157 | ||
6ae2364d | 1158 | packet_done(); |
7368a6c8 | 1159 | if (c == NULL) |
1160 | packet_disconnect("Received close confirmation for " | |
1161 | "out-of-range channel %d.", id); | |
1162 | if (c->type != SSH_CHANNEL_CLOSED) | |
1163 | packet_disconnect("Received close confirmation for " | |
1164 | "non-closed channel %d (type %d).", id, c->type); | |
1165 | channel_free(c->self); | |
1166 | } | |
8efc0c15 | 1167 | |
6ae2364d | 1168 | void |
7368a6c8 | 1169 | channel_input_open_confirmation(int type, int plen) |
8efc0c15 | 1170 | { |
7368a6c8 | 1171 | int id, remote_id; |
1172 | Channel *c; | |
5260325f | 1173 | |
7e7327a1 | 1174 | if (!compat20) |
1175 | packet_integrity_check(plen, 4 + 4, type); | |
5260325f | 1176 | |
7368a6c8 | 1177 | id = packet_get_int(); |
1178 | c = channel_lookup(id); | |
5260325f | 1179 | |
7368a6c8 | 1180 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1181 | packet_disconnect("Received open confirmation for " | |
1182 | "non-opening channel %d.", id); | |
1183 | remote_id = packet_get_int(); | |
aa3378df | 1184 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1185 | c->remote_id = remote_id; |
1186 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1187 | |
1188 | if (compat20) { | |
1189 | c->remote_window = packet_get_int(); | |
1190 | c->remote_maxpacket = packet_get_int(); | |
6ae2364d | 1191 | packet_done(); |
7e7327a1 | 1192 | if (c->cb_fn != NULL && c->cb_event == type) { |
1193 | debug("callback start"); | |
1194 | c->cb_fn(c->self, c->cb_arg); | |
1195 | debug("callback done"); | |
1196 | } | |
1197 | debug("channel %d: open confirm rwindow %d rmax %d", c->self, | |
1198 | c->remote_window, c->remote_maxpacket); | |
1199 | } | |
8efc0c15 | 1200 | } |
1201 | ||
6ae2364d | 1202 | void |
7368a6c8 | 1203 | channel_input_open_failure(int type, int plen) |
8efc0c15 | 1204 | { |
7368a6c8 | 1205 | int id; |
1206 | Channel *c; | |
5260325f | 1207 | |
7e7327a1 | 1208 | if (!compat20) |
1209 | packet_integrity_check(plen, 4, type); | |
7368a6c8 | 1210 | |
1211 | id = packet_get_int(); | |
1212 | c = channel_lookup(id); | |
1213 | ||
1214 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1215 | packet_disconnect("Received open failure for " | |
1216 | "non-opening channel %d.", id); | |
7e7327a1 | 1217 | if (compat20) { |
1218 | int reason = packet_get_int(); | |
1219 | char *msg = packet_get_string(NULL); | |
6ae2364d | 1220 | char *lang = packet_get_string(NULL); |
7e7327a1 | 1221 | log("channel_open_failure: %d: reason %d: %s", id, reason, msg); |
6ae2364d | 1222 | packet_done(); |
7e7327a1 | 1223 | xfree(msg); |
6ae2364d | 1224 | xfree(lang); |
7e7327a1 | 1225 | } |
5260325f | 1226 | /* Free the channel. This will also close the socket. */ |
7368a6c8 | 1227 | channel_free(id); |
8efc0c15 | 1228 | } |
1229 | ||
7e7327a1 | 1230 | void |
1231 | channel_input_channel_request(int type, int plen) | |
1232 | { | |
1233 | int id; | |
1234 | Channel *c; | |
1235 | ||
1236 | id = packet_get_int(); | |
1237 | c = channel_lookup(id); | |
1238 | ||
1239 | if (c == NULL || | |
1240 | (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) | |
1241 | packet_disconnect("Received request for " | |
1242 | "non-open channel %d.", id); | |
1243 | if (c->cb_fn != NULL && c->cb_event == type) { | |
1244 | debug("callback start"); | |
1245 | c->cb_fn(c->self, c->cb_arg); | |
1246 | debug("callback done"); | |
1247 | } else { | |
1248 | char *service = packet_get_string(NULL); | |
1249 | debug("channel: %d rcvd request for %s", c->self, service); | |
1250 | debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); | |
1251 | xfree(service); | |
1252 | } | |
1253 | } | |
1254 | ||
6ae2364d | 1255 | void |
7e7327a1 | 1256 | channel_input_window_adjust(int type, int plen) |
1257 | { | |
1258 | Channel *c; | |
1259 | int id, adjust; | |
1260 | ||
1261 | if (!compat20) | |
1262 | return; | |
1263 | ||
1264 | /* Get the channel number and verify it. */ | |
1265 | id = packet_get_int(); | |
1266 | c = channel_lookup(id); | |
1267 | ||
1268 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1269 | log("Received window adjust for " | |
1270 | "non-open channel %d.", id); | |
1271 | return; | |
1272 | } | |
1273 | adjust = packet_get_int(); | |
6ae2364d | 1274 | packet_done(); |
7e7327a1 | 1275 | debug("channel %d: rcvd adjust %d", id, adjust); |
1276 | c->remote_window += adjust; | |
1277 | } | |
1278 | ||
aa3378df | 1279 | /* |
1280 | * Stops listening for channels, and removes any unix domain sockets that we | |
1281 | * might have. | |
1282 | */ | |
8efc0c15 | 1283 | |
6ae2364d | 1284 | void |
5260325f | 1285 | channel_stop_listening() |
8efc0c15 | 1286 | { |
5260325f | 1287 | int i; |
1288 | for (i = 0; i < channels_alloc; i++) { | |
1289 | switch (channels[i].type) { | |
1290 | case SSH_CHANNEL_AUTH_SOCKET: | |
1291 | close(channels[i].sock); | |
1292 | remove(channels[i].path); | |
1293 | channel_free(i); | |
1294 | break; | |
1295 | case SSH_CHANNEL_PORT_LISTENER: | |
1296 | case SSH_CHANNEL_X11_LISTENER: | |
1297 | close(channels[i].sock); | |
1298 | channel_free(i); | |
1299 | break; | |
1300 | default: | |
1301 | break; | |
1302 | } | |
8efc0c15 | 1303 | } |
8efc0c15 | 1304 | } |
1305 | ||
aa3378df | 1306 | /* |
0fbe8c74 | 1307 | * Closes the sockets/fds of all channels. This is used to close extra file |
aa3378df | 1308 | * descriptors after a fork. |
1309 | */ | |
8efc0c15 | 1310 | |
6ae2364d | 1311 | void |
5260325f | 1312 | channel_close_all() |
8efc0c15 | 1313 | { |
5260325f | 1314 | int i; |
0fbe8c74 | 1315 | for (i = 0; i < channels_alloc; i++) |
5260325f | 1316 | if (channels[i].type != SSH_CHANNEL_FREE) |
0fbe8c74 | 1317 | channel_close_fds(&channels[i]); |
8efc0c15 | 1318 | } |
1319 | ||
1320 | /* Returns the maximum file descriptor number used by the channels. */ | |
1321 | ||
6ae2364d | 1322 | int |
5260325f | 1323 | channel_max_fd() |
8efc0c15 | 1324 | { |
5260325f | 1325 | return channel_max_fd_value; |
8efc0c15 | 1326 | } |
1327 | ||
1328 | /* Returns true if any channel is still open. */ | |
1329 | ||
6ae2364d | 1330 | int |
5260325f | 1331 | channel_still_open() |
8efc0c15 | 1332 | { |
5260325f | 1333 | unsigned int i; |
1334 | for (i = 0; i < channels_alloc; i++) | |
1335 | switch (channels[i].type) { | |
1336 | case SSH_CHANNEL_FREE: | |
1337 | case SSH_CHANNEL_X11_LISTENER: | |
1338 | case SSH_CHANNEL_PORT_LISTENER: | |
1339 | case SSH_CHANNEL_CLOSED: | |
1340 | case SSH_CHANNEL_AUTH_SOCKET: | |
1341 | continue; | |
7e7327a1 | 1342 | case SSH_CHANNEL_LARVAL: |
1343 | if (!compat20) | |
1344 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
1345 | continue; | |
5260325f | 1346 | case SSH_CHANNEL_OPENING: |
1347 | case SSH_CHANNEL_OPEN: | |
1348 | case SSH_CHANNEL_X11_OPEN: | |
1349 | return 1; | |
1350 | case SSH_CHANNEL_INPUT_DRAINING: | |
1351 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
1352 | if (!compat13) | |
1353 | fatal("cannot happen: OUT_DRAIN"); | |
1354 | return 1; | |
1355 | default: | |
1356 | fatal("channel_still_open: bad channel type %d", channels[i].type); | |
1357 | /* NOTREACHED */ | |
1358 | } | |
1359 | return 0; | |
8efc0c15 | 1360 | } |
1361 | ||
aa3378df | 1362 | /* |
1363 | * Returns a message describing the currently open forwarded connections, | |
1364 | * suitable for sending to the client. The message contains crlf pairs for | |
1365 | * newlines. | |
1366 | */ | |
8efc0c15 | 1367 | |
5260325f | 1368 | char * |
1369 | channel_open_message() | |
8efc0c15 | 1370 | { |
5260325f | 1371 | Buffer buffer; |
1372 | int i; | |
1373 | char buf[512], *cp; | |
1374 | ||
1375 | buffer_init(&buffer); | |
1376 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
8efc0c15 | 1377 | buffer_append(&buffer, buf, strlen(buf)); |
5260325f | 1378 | for (i = 0; i < channels_alloc; i++) { |
1379 | Channel *c = &channels[i]; | |
1380 | switch (c->type) { | |
1381 | case SSH_CHANNEL_FREE: | |
1382 | case SSH_CHANNEL_X11_LISTENER: | |
1383 | case SSH_CHANNEL_PORT_LISTENER: | |
1384 | case SSH_CHANNEL_CLOSED: | |
1385 | case SSH_CHANNEL_AUTH_SOCKET: | |
1386 | continue; | |
7e7327a1 | 1387 | case SSH_CHANNEL_LARVAL: |
5260325f | 1388 | case SSH_CHANNEL_OPENING: |
1389 | case SSH_CHANNEL_OPEN: | |
1390 | case SSH_CHANNEL_X11_OPEN: | |
1391 | case SSH_CHANNEL_INPUT_DRAINING: | |
1392 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
7368a6c8 | 1393 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", |
48e671d5 | 1394 | c->self, c->remote_name, |
1395 | c->type, c->remote_id, | |
1396 | c->istate, buffer_len(&c->input), | |
7368a6c8 | 1397 | c->ostate, buffer_len(&c->output), |
1398 | c->rfd, c->wfd); | |
5260325f | 1399 | buffer_append(&buffer, buf, strlen(buf)); |
1400 | continue; | |
1401 | default: | |
7368a6c8 | 1402 | fatal("channel_open_message: bad channel type %d", c->type); |
5260325f | 1403 | /* NOTREACHED */ |
1404 | } | |
1405 | } | |
1406 | buffer_append(&buffer, "\0", 1); | |
1407 | cp = xstrdup(buffer_ptr(&buffer)); | |
1408 | buffer_free(&buffer); | |
1409 | return cp; | |
8efc0c15 | 1410 | } |
1411 | ||
aa3378df | 1412 | /* |
1413 | * Initiate forwarding of connections to local port "port" through the secure | |
1414 | * channel to host:port from remote side. | |
1415 | */ | |
8efc0c15 | 1416 | |
6ae2364d | 1417 | void |
57112b5a | 1418 | channel_request_local_forwarding(u_short port, const char *host, |
95f1eccc | 1419 | u_short host_port, int gateway_ports) |
8efc0c15 | 1420 | { |
48e671d5 | 1421 | int success, ch, sock, on = 1; |
1422 | struct addrinfo hints, *ai, *aitop; | |
1423 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
aa3378df | 1424 | struct linger linger; |
5260325f | 1425 | |
1426 | if (strlen(host) > sizeof(channels[0].path) - 1) | |
1427 | packet_disconnect("Forward host name too long."); | |
1428 | ||
aa3378df | 1429 | /* |
48e671d5 | 1430 | * getaddrinfo returns a loopback address if the hostname is |
1431 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 1432 | */ |
48e671d5 | 1433 | memset(&hints, 0, sizeof(hints)); |
1434 | hints.ai_family = IPv4or6; | |
1435 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
1436 | hints.ai_socktype = SOCK_STREAM; | |
1437 | snprintf(strport, sizeof strport, "%d", port); | |
1438 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) | |
1439 | packet_disconnect("getaddrinfo: fatal error"); | |
1440 | ||
1441 | success = 0; | |
1442 | for (ai = aitop; ai; ai = ai->ai_next) { | |
1443 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1444 | continue; | |
1445 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
1446 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
1447 | error("channel_request_local_forwarding: getnameinfo failed"); | |
1448 | continue; | |
1449 | } | |
1450 | /* Create a port to listen for the host. */ | |
1451 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1452 | if (sock < 0) { | |
1453 | /* this is no error since kernel may not support ipv6 */ | |
1454 | verbose("socket: %.100s", strerror(errno)); | |
1455 | continue; | |
1456 | } | |
1457 | /* | |
1458 | * Set socket options. We would like the socket to disappear | |
1459 | * as soon as it has been closed for whatever reason. | |
1460 | */ | |
1461 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); | |
1462 | linger.l_onoff = 1; | |
1463 | linger.l_linger = 5; | |
1464 | setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); | |
1465 | debug("Local forwarding listening on %s port %s.", ntop, strport); | |
1466 | ||
1467 | /* Bind the socket to the address. */ | |
1468 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1469 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 1470 | if (!ai->ai_next) |
1471 | error("bind: %.100s", strerror(errno)); | |
1472 | else | |
1473 | verbose("bind: %.100s", strerror(errno)); | |
1474 | ||
48e671d5 | 1475 | close(sock); |
1476 | continue; | |
1477 | } | |
1478 | /* Start listening for connections on the socket. */ | |
1479 | if (listen(sock, 5) < 0) { | |
1480 | error("listen: %.100s", strerror(errno)); | |
1481 | close(sock); | |
1482 | continue; | |
1483 | } | |
1484 | /* Allocate a channel number for the socket. */ | |
7368a6c8 | 1485 | ch = channel_new( |
1486 | "port listener", SSH_CHANNEL_PORT_LISTENER, | |
1487 | sock, sock, -1, | |
0b242b12 | 1488 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
7368a6c8 | 1489 | 0, xstrdup("port listener")); |
48e671d5 | 1490 | strlcpy(channels[ch].path, host, sizeof(channels[ch].path)); |
1491 | channels[ch].host_port = host_port; | |
1492 | channels[ch].listening_port = port; | |
1493 | success = 1; | |
1494 | } | |
1495 | if (success == 0) | |
1496 | packet_disconnect("cannot listen port: %d", port); | |
1497 | freeaddrinfo(aitop); | |
5260325f | 1498 | } |
8efc0c15 | 1499 | |
aa3378df | 1500 | /* |
1501 | * Initiate forwarding of connections to port "port" on remote host through | |
1502 | * the secure channel to host:port from local side. | |
1503 | */ | |
8efc0c15 | 1504 | |
6ae2364d | 1505 | void |
7368a6c8 | 1506 | channel_request_remote_forwarding(u_short listen_port, const char *host_to_connect, |
1507 | u_short port_to_connect) | |
8efc0c15 | 1508 | { |
5260325f | 1509 | int payload_len; |
1510 | /* Record locally that connection to this host/port is permitted. */ | |
1511 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
1512 | fatal("channel_request_remote_forwarding: too many forwards"); | |
1513 | ||
7368a6c8 | 1514 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); |
1515 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
1516 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
5260325f | 1517 | num_permitted_opens++; |
1518 | ||
1519 | /* Send the forward request to the remote side. */ | |
7e7327a1 | 1520 | if (compat20) { |
1521 | const char *address_to_bind = "0.0.0.0"; | |
1522 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
1523 | packet_put_cstring("tcpip-forward"); | |
1524 | packet_put_char(0); /* boolean: want reply */ | |
1525 | packet_put_cstring(address_to_bind); | |
1526 | packet_put_int(listen_port); | |
1527 | } else { | |
1528 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
7e7327a1 | 1529 | packet_put_int(listen_port); |
d6f24e45 | 1530 | packet_put_cstring(host_to_connect); |
1531 | packet_put_int(port_to_connect); | |
7e7327a1 | 1532 | packet_send(); |
1533 | packet_write_wait(); | |
1534 | /* | |
1535 | * Wait for response from the remote side. It will send a disconnect | |
1536 | * message on failure, and we will never see it here. | |
1537 | */ | |
1538 | packet_read_expect(&payload_len, SSH_SMSG_SUCCESS); | |
1539 | } | |
8efc0c15 | 1540 | } |
1541 | ||
aa3378df | 1542 | /* |
1543 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
1544 | * listening for the port, and sends back a success reply (or disconnect | |
1545 | * message if there was an error). This never returns if there was an error. | |
1546 | */ | |
8efc0c15 | 1547 | |
6ae2364d | 1548 | void |
1d1ffb87 | 1549 | channel_input_port_forward_request(int is_root, int gateway_ports) |
8efc0c15 | 1550 | { |
57112b5a | 1551 | u_short port, host_port; |
5260325f | 1552 | char *hostname; |
1553 | ||
1554 | /* Get arguments from the packet. */ | |
1555 | port = packet_get_int(); | |
1556 | hostname = packet_get_string(NULL); | |
1557 | host_port = packet_get_int(); | |
1558 | ||
aa3378df | 1559 | /* |
1560 | * Check that an unprivileged user is not trying to forward a | |
1561 | * privileged port. | |
1562 | */ | |
5260325f | 1563 | if (port < IPPORT_RESERVED && !is_root) |
1564 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
1565 | port); | |
95f1eccc | 1566 | /* |
1567 | * Initiate forwarding, | |
95f1eccc | 1568 | */ |
1d1ffb87 | 1569 | channel_request_local_forwarding(port, hostname, host_port, gateway_ports); |
5260325f | 1570 | |
1571 | /* Free the argument string. */ | |
1572 | xfree(hostname); | |
8efc0c15 | 1573 | } |
1574 | ||
7368a6c8 | 1575 | /* XXX move to aux.c */ |
1576 | int | |
1577 | channel_connect_to(const char *host, u_short host_port) | |
8efc0c15 | 1578 | { |
48e671d5 | 1579 | struct addrinfo hints, *ai, *aitop; |
1580 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
1581 | int gaierr; | |
7368a6c8 | 1582 | int sock = -1; |
48e671d5 | 1583 | |
1584 | memset(&hints, 0, sizeof(hints)); | |
1585 | hints.ai_family = IPv4or6; | |
1586 | hints.ai_socktype = SOCK_STREAM; | |
1587 | snprintf(strport, sizeof strport, "%d", host_port); | |
1588 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { | |
1589 | error("%.100s: unknown host (%s)", host, gai_strerror(gaierr)); | |
7368a6c8 | 1590 | return -1; |
48e671d5 | 1591 | } |
48e671d5 | 1592 | for (ai = aitop; ai; ai = ai->ai_next) { |
1593 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1594 | continue; | |
1595 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
1596 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
7368a6c8 | 1597 | error("channel_connect_to: getnameinfo failed"); |
48e671d5 | 1598 | continue; |
5260325f | 1599 | } |
48e671d5 | 1600 | /* Create the socket. */ |
1601 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1602 | if (sock < 0) { | |
1603 | error("socket: %.100s", strerror(errno)); | |
1604 | continue; | |
5260325f | 1605 | } |
48e671d5 | 1606 | /* Connect to the host/port. */ |
1607 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1608 | error("connect %.100s port %s: %.100s", ntop, strport, | |
1609 | strerror(errno)); | |
1610 | close(sock); | |
1611 | continue; /* fail -- try next */ | |
1612 | } | |
1613 | break; /* success */ | |
5260325f | 1614 | |
5260325f | 1615 | } |
48e671d5 | 1616 | freeaddrinfo(aitop); |
48e671d5 | 1617 | if (!ai) { |
1618 | error("connect %.100s port %d: failed.", host, host_port); | |
7368a6c8 | 1619 | return -1; |
8efc0c15 | 1620 | } |
7368a6c8 | 1621 | /* success */ |
1622 | return sock; | |
1623 | } | |
48e671d5 | 1624 | |
7368a6c8 | 1625 | /* |
1626 | * This is called after receiving PORT_OPEN message. This attempts to | |
1627 | * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION | |
1628 | * or CHANNEL_OPEN_FAILURE. | |
1629 | */ | |
5260325f | 1630 | |
6ae2364d | 1631 | void |
7368a6c8 | 1632 | channel_input_port_open(int type, int plen) |
1633 | { | |
1634 | u_short host_port; | |
1635 | char *host, *originator_string; | |
1636 | int remote_channel, sock = -1, newch, i, denied; | |
1637 | unsigned int host_len, originator_len; | |
5260325f | 1638 | |
7368a6c8 | 1639 | /* Get remote channel number. */ |
1640 | remote_channel = packet_get_int(); | |
5260325f | 1641 | |
7368a6c8 | 1642 | /* Get host name to connect to. */ |
1643 | host = packet_get_string(&host_len); | |
5260325f | 1644 | |
7368a6c8 | 1645 | /* Get port to connect to. */ |
1646 | host_port = packet_get_int(); | |
5260325f | 1647 | |
7368a6c8 | 1648 | /* Get remote originator name. */ |
1649 | if (have_hostname_in_open) { | |
1650 | originator_string = packet_get_string(&originator_len); | |
1651 | originator_len += 4; /* size of packet_int */ | |
1652 | } else { | |
1653 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
1654 | originator_len = 0; /* no originator supplied */ | |
1655 | } | |
5260325f | 1656 | |
7368a6c8 | 1657 | packet_integrity_check(plen, |
1658 | 4 + 4 + host_len + 4 + originator_len, SSH_MSG_PORT_OPEN); | |
1659 | ||
1660 | /* Check if opening that port is permitted. */ | |
1661 | denied = 0; | |
1662 | if (!all_opens_permitted) { | |
1663 | /* Go trough all permitted ports. */ | |
1664 | for (i = 0; i < num_permitted_opens; i++) | |
1665 | if (permitted_opens[i].port_to_connect == host_port && | |
1666 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
1667 | break; | |
1668 | ||
1669 | /* Check if we found the requested port among those permitted. */ | |
1670 | if (i >= num_permitted_opens) { | |
1671 | /* The port is not permitted. */ | |
1672 | log("Received request to connect to %.100s:%d, but the request was denied.", | |
1673 | host, host_port); | |
1674 | denied = 1; | |
1675 | } | |
1676 | } | |
1677 | sock = denied ? -1 : channel_connect_to(host, host_port); | |
1678 | if (sock > 0) { | |
1679 | /* Allocate a channel for this connection. */ | |
1680 | newch = channel_allocate(SSH_CHANNEL_OPEN, sock, originator_string); | |
1681 | channels[newch].remote_id = remote_channel; | |
1682 | ||
1683 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1684 | packet_put_int(remote_channel); | |
1685 | packet_put_int(newch); | |
1686 | packet_send(); | |
1687 | } else { | |
1688 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1689 | packet_put_int(remote_channel); | |
1690 | packet_send(); | |
1691 | } | |
1692 | xfree(host); | |
8efc0c15 | 1693 | } |
1694 | ||
aa3378df | 1695 | /* |
1696 | * Creates an internet domain socket for listening for X11 connections. | |
1697 | * Returns a suitable value for the DISPLAY variable, or NULL if an error | |
1698 | * occurs. | |
1699 | */ | |
8efc0c15 | 1700 | |
48e671d5 | 1701 | #define NUM_SOCKS 10 |
1702 | ||
5260325f | 1703 | char * |
95f1eccc | 1704 | x11_create_display_inet(int screen_number, int x11_display_offset) |
8efc0c15 | 1705 | { |
57112b5a | 1706 | int display_number, sock; |
1707 | u_short port; | |
48e671d5 | 1708 | struct addrinfo hints, *ai, *aitop; |
1709 | char strport[NI_MAXSERV]; | |
1710 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
1711 | char display[512]; | |
5260325f | 1712 | char hostname[MAXHOSTNAMELEN]; |
1713 | ||
95f1eccc | 1714 | for (display_number = x11_display_offset; |
5260325f | 1715 | display_number < MAX_DISPLAYS; |
1716 | display_number++) { | |
1717 | port = 6000 + display_number; | |
48e671d5 | 1718 | memset(&hints, 0, sizeof(hints)); |
1719 | hints.ai_family = IPv4or6; | |
1720 | hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */ | |
1721 | hints.ai_socktype = SOCK_STREAM; | |
1722 | snprintf(strport, sizeof strport, "%d", port); | |
1723 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
1724 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
5260325f | 1725 | return NULL; |
1726 | } | |
48e671d5 | 1727 | for (ai = aitop; ai; ai = ai->ai_next) { |
1728 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1729 | continue; | |
1730 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1731 | if (sock < 0) { | |
80a44451 | 1732 | if (errno != EINVAL) { |
1733 | error("socket: %.100s", strerror(errno)); | |
1734 | return NULL; | |
1735 | } else { | |
1736 | debug("Socket family %d not supported [X11 disp create]", ai->ai_family); | |
1737 | continue; | |
1738 | } | |
48e671d5 | 1739 | } |
1740 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1741 | debug("bind port %d: %.100s", port, strerror(errno)); | |
1742 | shutdown(sock, SHUT_RDWR); | |
1743 | close(sock); | |
16218745 | 1744 | |
1745 | if (ai->ai_next) | |
1746 | continue; | |
1747 | ||
48e671d5 | 1748 | for (n = 0; n < num_socks; n++) { |
1749 | shutdown(socks[n], SHUT_RDWR); | |
1750 | close(socks[n]); | |
1751 | } | |
1752 | num_socks = 0; | |
1753 | break; | |
1754 | } | |
1755 | socks[num_socks++] = sock; | |
80faa19f | 1756 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 1757 | if (num_socks == NUM_SOCKS) |
1758 | break; | |
80faa19f | 1759 | #else |
1760 | break; | |
1761 | #endif | |
5260325f | 1762 | } |
48e671d5 | 1763 | if (num_socks > 0) |
1764 | break; | |
5260325f | 1765 | } |
1766 | if (display_number >= MAX_DISPLAYS) { | |
1767 | error("Failed to allocate internet-domain X11 display socket."); | |
1768 | return NULL; | |
8efc0c15 | 1769 | } |
5260325f | 1770 | /* Start listening for connections on the socket. */ |
48e671d5 | 1771 | for (n = 0; n < num_socks; n++) { |
1772 | sock = socks[n]; | |
1773 | if (listen(sock, 5) < 0) { | |
1774 | error("listen: %.100s", strerror(errno)); | |
1775 | shutdown(sock, SHUT_RDWR); | |
1776 | close(sock); | |
1777 | return NULL; | |
1778 | } | |
8efc0c15 | 1779 | } |
48e671d5 | 1780 | |
5260325f | 1781 | /* Set up a suitable value for the DISPLAY variable. */ |
a7effaac | 1782 | |
5260325f | 1783 | if (gethostname(hostname, sizeof(hostname)) < 0) |
1784 | fatal("gethostname: %.100s", strerror(errno)); | |
a7effaac | 1785 | |
1786 | #ifdef IPADDR_IN_DISPLAY | |
1787 | /* | |
1788 | * HPUX detects the local hostname in the DISPLAY variable and tries | |
1789 | * to set up a shared memory connection to the server, which it | |
1790 | * incorrectly supposes to be local. | |
1791 | * | |
1792 | * The workaround - as used in later $$H and other programs - is | |
1793 | * is to set display to the host's IP address. | |
1794 | */ | |
1795 | { | |
1796 | struct hostent *he; | |
1797 | struct in_addr my_addr; | |
1798 | ||
1799 | he = gethostbyname(hostname); | |
1800 | if (he == NULL) { | |
1801 | error("[X11-broken-fwd-hostname-workaround] Could not get " | |
1802 | "IP address for hostname %s.", hostname); | |
1803 | ||
1804 | packet_send_debug("[X11-broken-fwd-hostname-workaround]" | |
1805 | "Could not get IP address for hostname %s.", hostname); | |
1806 | ||
1807 | shutdown(sock, SHUT_RDWR); | |
1808 | close(sock); | |
1809 | ||
1810 | return NULL; | |
1811 | } | |
1812 | ||
1813 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
1814 | ||
1815 | /* Set DISPLAY to <ip address>:screen.display */ | |
48e671d5 | 1816 | snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr), |
a7effaac | 1817 | display_number, screen_number); |
1818 | } | |
1819 | #else /* IPADDR_IN_DISPLAY */ | |
1820 | /* Just set DISPLAY to hostname:screen.display */ | |
48e671d5 | 1821 | snprintf(display, sizeof display, "%.400s:%d.%d", hostname, |
a7effaac | 1822 | display_number, screen_number); |
1823 | #endif /* IPADDR_IN_DISPLAY */ | |
5260325f | 1824 | |
48e671d5 | 1825 | /* Allocate a channel for each socket. */ |
1826 | for (n = 0; n < num_socks; n++) { | |
1827 | sock = socks[n]; | |
0b242b12 | 1828 | (void) channel_new("x11 listener", |
1829 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, | |
1830 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, | |
1831 | 0, xstrdup("X11 inet listener")); | |
48e671d5 | 1832 | } |
5260325f | 1833 | |
1834 | /* Return a suitable value for the DISPLAY environment variable. */ | |
48e671d5 | 1835 | return xstrdup(display); |
8efc0c15 | 1836 | } |
1837 | ||
1838 | #ifndef X_UNIX_PATH | |
1839 | #define X_UNIX_PATH "/tmp/.X11-unix/X" | |
1840 | #endif | |
1841 | ||
1842 | static | |
1843 | int | |
2f450969 | 1844 | connect_local_xsocket(unsigned int dnr) |
8efc0c15 | 1845 | { |
5260325f | 1846 | static const char *const x_sockets[] = { |
1847 | X_UNIX_PATH "%u", | |
1848 | "/var/X/.X11-unix/X" "%u", | |
1849 | "/usr/spool/sockets/X11/" "%u", | |
1850 | NULL | |
1851 | }; | |
1852 | int sock; | |
1853 | struct sockaddr_un addr; | |
1854 | const char *const * path; | |
1855 | ||
1856 | for (path = x_sockets; *path; ++path) { | |
1857 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
1858 | if (sock < 0) | |
1859 | error("socket: %.100s", strerror(errno)); | |
1860 | memset(&addr, 0, sizeof(addr)); | |
1861 | addr.sun_family = AF_UNIX; | |
1862 | snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr); | |
1863 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
1864 | return sock; | |
1865 | close(sock); | |
1866 | } | |
1867 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); | |
1868 | return -1; | |
8efc0c15 | 1869 | } |
1870 | ||
0b242b12 | 1871 | int |
1872 | x11_connect_display(void) | |
8efc0c15 | 1873 | { |
0b242b12 | 1874 | int display_number, sock = 0; |
5260325f | 1875 | const char *display; |
0b242b12 | 1876 | char buf[1024], *cp; |
48e671d5 | 1877 | struct addrinfo hints, *ai, *aitop; |
1878 | char strport[NI_MAXSERV]; | |
1879 | int gaierr; | |
5260325f | 1880 | |
5260325f | 1881 | /* Try to open a socket for the local X server. */ |
1882 | display = getenv("DISPLAY"); | |
1883 | if (!display) { | |
1884 | error("DISPLAY not set."); | |
0b242b12 | 1885 | return -1; |
5260325f | 1886 | } |
aa3378df | 1887 | /* |
1888 | * Now we decode the value of the DISPLAY variable and make a | |
1889 | * connection to the real X server. | |
1890 | */ | |
1891 | ||
1892 | /* | |
1893 | * Check if it is a unix domain socket. Unix domain displays are in | |
1894 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
1895 | */ | |
5260325f | 1896 | if (strncmp(display, "unix:", 5) == 0 || |
1897 | display[0] == ':') { | |
1898 | /* Connect to the unix domain socket. */ | |
1899 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
1900 | error("Could not parse display number from DISPLAY: %.100s", | |
1901 | display); | |
0b242b12 | 1902 | return -1; |
5260325f | 1903 | } |
1904 | /* Create a socket. */ | |
1905 | sock = connect_local_xsocket(display_number); | |
1906 | if (sock < 0) | |
0b242b12 | 1907 | return -1; |
5260325f | 1908 | |
1909 | /* OK, we now have a connection to the display. */ | |
0b242b12 | 1910 | return sock; |
5260325f | 1911 | } |
aa3378df | 1912 | /* |
1913 | * Connect to an inet socket. The DISPLAY value is supposedly | |
1914 | * hostname:d[.s], where hostname may also be numeric IP address. | |
1915 | */ | |
5260325f | 1916 | strncpy(buf, display, sizeof(buf)); |
1917 | buf[sizeof(buf) - 1] = 0; | |
1918 | cp = strchr(buf, ':'); | |
1919 | if (!cp) { | |
1920 | error("Could not find ':' in DISPLAY: %.100s", display); | |
0b242b12 | 1921 | return -1; |
5260325f | 1922 | } |
1923 | *cp = 0; | |
aa3378df | 1924 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 1925 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
1926 | error("Could not parse display number from DISPLAY: %.100s", | |
1927 | display); | |
0b242b12 | 1928 | return -1; |
5260325f | 1929 | } |
5260325f | 1930 | |
48e671d5 | 1931 | /* Look up the host address */ |
1932 | memset(&hints, 0, sizeof(hints)); | |
1933 | hints.ai_family = IPv4or6; | |
1934 | hints.ai_socktype = SOCK_STREAM; | |
1935 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
1936 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
1937 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
0b242b12 | 1938 | return -1; |
8efc0c15 | 1939 | } |
48e671d5 | 1940 | for (ai = aitop; ai; ai = ai->ai_next) { |
1941 | /* Create a socket. */ | |
1942 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1943 | if (sock < 0) { | |
1944 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 1945 | continue; |
1946 | } | |
1947 | /* Connect it to the display. */ | |
1948 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1949 | debug("connect %.100s port %d: %.100s", buf, | |
1950 | 6000 + display_number, strerror(errno)); | |
1951 | close(sock); | |
1952 | continue; | |
1953 | } | |
1954 | /* Success */ | |
1955 | break; | |
48e671d5 | 1956 | } |
48e671d5 | 1957 | freeaddrinfo(aitop); |
1958 | if (!ai) { | |
6ae2364d | 1959 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, |
48e671d5 | 1960 | strerror(errno)); |
0b242b12 | 1961 | return -1; |
8efc0c15 | 1962 | } |
0b242b12 | 1963 | return sock; |
1964 | } | |
5260325f | 1965 | |
0b242b12 | 1966 | /* |
1967 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
1968 | * the remote channel number. We should do whatever we want, and respond | |
1969 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
1970 | */ | |
5260325f | 1971 | |
0b242b12 | 1972 | void |
1973 | x11_input_open(int type, int plen) | |
1974 | { | |
1975 | int remote_channel, sock = 0, newch; | |
1976 | char *remote_host; | |
1977 | unsigned int remote_len; | |
5260325f | 1978 | |
0b242b12 | 1979 | /* Get remote channel number. */ |
1980 | remote_channel = packet_get_int(); | |
5260325f | 1981 | |
0b242b12 | 1982 | /* Get remote originator name. */ |
1983 | if (have_hostname_in_open) { | |
1984 | remote_host = packet_get_string(&remote_len); | |
1985 | remote_len += 4; | |
1986 | } else { | |
1987 | remote_host = xstrdup("unknown (remote did not supply name)"); | |
1988 | remote_len = 0; | |
1989 | } | |
1990 | ||
1991 | debug("Received X11 open request."); | |
1992 | packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN); | |
1993 | ||
1994 | /* Obtain a connection to the real X display. */ | |
1995 | sock = x11_connect_display(); | |
1996 | if (sock == -1) { | |
1997 | /* Send refusal to the remote host. */ | |
1998 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1999 | packet_put_int(remote_channel); | |
2000 | packet_send(); | |
2001 | } else { | |
2002 | /* Allocate a channel for this connection. */ | |
2003 | newch = channel_allocate( | |
2004 | (x11_saved_proto == NULL) ? | |
2005 | SSH_CHANNEL_OPEN : SSH_CHANNEL_X11_OPEN, | |
2006 | sock, remote_host); | |
2007 | channels[newch].remote_id = remote_channel; | |
2008 | ||
2009 | /* Send a confirmation to the remote host. */ | |
2010 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2011 | packet_put_int(remote_channel); | |
2012 | packet_put_int(newch); | |
2013 | packet_send(); | |
2014 | } | |
8efc0c15 | 2015 | } |
2016 | ||
aa3378df | 2017 | /* |
2018 | * Requests forwarding of X11 connections, generates fake authentication | |
2019 | * data, and enables authentication spoofing. | |
2020 | */ | |
8efc0c15 | 2021 | |
6ae2364d | 2022 | void |
0b242b12 | 2023 | x11_request_forwarding_with_spoofing(int client_session_id, |
2024 | const char *proto, const char *data) | |
8efc0c15 | 2025 | { |
5260325f | 2026 | unsigned int data_len = (unsigned int) strlen(data) / 2; |
2027 | unsigned int i, value; | |
2028 | char *new_data; | |
2029 | int screen_number; | |
2030 | const char *cp; | |
2031 | u_int32_t rand = 0; | |
2032 | ||
2033 | cp = getenv("DISPLAY"); | |
2034 | if (cp) | |
2035 | cp = strchr(cp, ':'); | |
2036 | if (cp) | |
2037 | cp = strchr(cp, '.'); | |
2038 | if (cp) | |
2039 | screen_number = atoi(cp + 1); | |
2040 | else | |
2041 | screen_number = 0; | |
2042 | ||
2043 | /* Save protocol name. */ | |
2044 | x11_saved_proto = xstrdup(proto); | |
2045 | ||
aa3378df | 2046 | /* |
2047 | * Extract real authentication data and generate fake data of the | |
2048 | * same length. | |
2049 | */ | |
5260325f | 2050 | x11_saved_data = xmalloc(data_len); |
2051 | x11_fake_data = xmalloc(data_len); | |
2052 | for (i = 0; i < data_len; i++) { | |
2053 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
2054 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
2055 | if (i % 4 == 0) | |
2056 | rand = arc4random(); | |
2057 | x11_saved_data[i] = value; | |
2058 | x11_fake_data[i] = rand & 0xff; | |
2059 | rand >>= 8; | |
2060 | } | |
2061 | x11_saved_data_len = data_len; | |
2062 | x11_fake_data_len = data_len; | |
2063 | ||
2064 | /* Convert the fake data into hex. */ | |
2065 | new_data = xmalloc(2 * data_len + 1); | |
2066 | for (i = 0; i < data_len; i++) | |
2067 | sprintf(new_data + 2 * i, "%02x", (unsigned char) x11_fake_data[i]); | |
2068 | ||
2069 | /* Send the request packet. */ | |
0b242b12 | 2070 | if (compat20) { |
2071 | channel_request_start(client_session_id, "x11-req", 0); | |
2072 | packet_put_char(0); /* XXX bool single connection */ | |
2073 | } else { | |
2074 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
2075 | } | |
2076 | packet_put_cstring(proto); | |
2077 | packet_put_cstring(new_data); | |
5260325f | 2078 | packet_put_int(screen_number); |
2079 | packet_send(); | |
2080 | packet_write_wait(); | |
2081 | xfree(new_data); | |
8efc0c15 | 2082 | } |
2083 | ||
2084 | /* Sends a message to the server to request authentication fd forwarding. */ | |
2085 | ||
6ae2364d | 2086 | void |
5260325f | 2087 | auth_request_forwarding() |
8efc0c15 | 2088 | { |
5260325f | 2089 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2090 | packet_send(); | |
2091 | packet_write_wait(); | |
8efc0c15 | 2092 | } |
2093 | ||
aa3378df | 2094 | /* |
2095 | * Returns the name of the forwarded authentication socket. Returns NULL if | |
2096 | * there is no forwarded authentication socket. The returned value points to | |
2097 | * a static buffer. | |
2098 | */ | |
8efc0c15 | 2099 | |
5260325f | 2100 | char * |
2101 | auth_get_socket_name() | |
8efc0c15 | 2102 | { |
5260325f | 2103 | return channel_forwarded_auth_socket_name; |
8efc0c15 | 2104 | } |
2105 | ||
2106 | /* removes the agent forwarding socket */ | |
2107 | ||
6ae2364d | 2108 | void |
5260325f | 2109 | cleanup_socket(void) |
2110 | { | |
2111 | remove(channel_forwarded_auth_socket_name); | |
2112 | rmdir(channel_forwarded_auth_socket_dir); | |
8efc0c15 | 2113 | } |
2114 | ||
aa3378df | 2115 | /* |
fa649821 | 2116 | * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
aa3378df | 2117 | * This starts forwarding authentication requests. |
2118 | */ | |
8efc0c15 | 2119 | |
fa649821 | 2120 | int |
5260325f | 2121 | auth_input_request_forwarding(struct passwd * pw) |
8efc0c15 | 2122 | { |
5260325f | 2123 | int sock, newch; |
2124 | struct sockaddr_un sunaddr; | |
2125 | ||
2126 | if (auth_get_socket_name() != NULL) | |
2127 | fatal("Protocol error: authentication forwarding requested twice."); | |
2128 | ||
2129 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
2130 | temporarily_use_uid(pw->pw_uid); | |
2131 | ||
2132 | /* Allocate a buffer for the socket name, and format the name. */ | |
2133 | channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME); | |
2134 | channel_forwarded_auth_socket_dir = xmalloc(MAX_SOCKET_NAME); | |
2135 | strlcpy(channel_forwarded_auth_socket_dir, "/tmp/ssh-XXXXXXXX", MAX_SOCKET_NAME); | |
2136 | ||
2137 | /* Create private directory for socket */ | |
fa649821 | 2138 | if (mkdtemp(channel_forwarded_auth_socket_dir) == NULL) { |
2139 | packet_send_debug("Agent forwarding disabled: mkdtemp() failed: %.100s", | |
2140 | strerror(errno)); | |
2141 | restore_uid(); | |
2142 | xfree(channel_forwarded_auth_socket_name); | |
2143 | xfree(channel_forwarded_auth_socket_dir); | |
2144 | channel_forwarded_auth_socket_name = NULL; | |
2145 | channel_forwarded_auth_socket_dir = NULL; | |
2146 | return 0; | |
2147 | } | |
5260325f | 2148 | snprintf(channel_forwarded_auth_socket_name, MAX_SOCKET_NAME, "%s/agent.%d", |
2149 | channel_forwarded_auth_socket_dir, (int) getpid()); | |
2150 | ||
2151 | if (atexit(cleanup_socket) < 0) { | |
2152 | int saved = errno; | |
2153 | cleanup_socket(); | |
2154 | packet_disconnect("socket: %.100s", strerror(saved)); | |
2155 | } | |
2156 | /* Create the socket. */ | |
2157 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2158 | if (sock < 0) | |
2159 | packet_disconnect("socket: %.100s", strerror(errno)); | |
2160 | ||
2161 | /* Bind it to the name. */ | |
2162 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
2163 | sunaddr.sun_family = AF_UNIX; | |
2164 | strncpy(sunaddr.sun_path, channel_forwarded_auth_socket_name, | |
2165 | sizeof(sunaddr.sun_path)); | |
2166 | ||
2167 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
2168 | packet_disconnect("bind: %.100s", strerror(errno)); | |
2169 | ||
2170 | /* Restore the privileged uid. */ | |
2171 | restore_uid(); | |
2172 | ||
2173 | /* Start listening on the socket. */ | |
2174 | if (listen(sock, 5) < 0) | |
2175 | packet_disconnect("listen: %.100s", strerror(errno)); | |
2176 | ||
2177 | /* Allocate a channel for the authentication agent socket. */ | |
2178 | newch = channel_allocate(SSH_CHANNEL_AUTH_SOCKET, sock, | |
2179 | xstrdup("auth socket")); | |
a408af76 | 2180 | strlcpy(channels[newch].path, channel_forwarded_auth_socket_name, |
2181 | sizeof(channels[newch].path)); | |
fa649821 | 2182 | return 1; |
8efc0c15 | 2183 | } |
2184 | ||
2185 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ | |
2186 | ||
6ae2364d | 2187 | void |
7368a6c8 | 2188 | auth_input_open_request(int type, int plen) |
8efc0c15 | 2189 | { |
5260325f | 2190 | int remch, sock, newch; |
2191 | char *dummyname; | |
2192 | ||
7368a6c8 | 2193 | packet_integrity_check(plen, 4, type); |
2194 | ||
5260325f | 2195 | /* Read the remote channel number from the message. */ |
2196 | remch = packet_get_int(); | |
2197 | ||
aa3378df | 2198 | /* |
2199 | * Get a connection to the local authentication agent (this may again | |
2200 | * get forwarded). | |
2201 | */ | |
5260325f | 2202 | sock = ssh_get_authentication_socket(); |
2203 | ||
aa3378df | 2204 | /* |
2205 | * If we could not connect the agent, send an error message back to | |
2206 | * the server. This should never happen unless the agent dies, | |
2207 | * because authentication forwarding is only enabled if we have an | |
2208 | * agent. | |
2209 | */ | |
5260325f | 2210 | if (sock < 0) { |
2211 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2212 | packet_put_int(remch); | |
2213 | packet_send(); | |
2214 | return; | |
2215 | } | |
2216 | debug("Forwarding authentication connection."); | |
2217 | ||
aa3378df | 2218 | /* |
2219 | * Dummy host name. This will be freed when the channel is freed; it | |
2220 | * will still be valid in the packet_put_string below since the | |
2221 | * channel cannot yet be freed at that point. | |
2222 | */ | |
5260325f | 2223 | dummyname = xstrdup("authentication agent connection"); |
2224 | ||
2225 | newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname); | |
2226 | channels[newch].remote_id = remch; | |
2227 | ||
2228 | /* Send a confirmation to the remote host. */ | |
2229 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2230 | packet_put_int(remch); | |
2231 | packet_put_int(newch); | |
2232 | packet_send(); | |
8efc0c15 | 2233 | } |
7e7327a1 | 2234 | |
2235 | void | |
0b242b12 | 2236 | channel_start_open(int id) |
7e7327a1 | 2237 | { |
2238 | Channel *c = channel_lookup(id); | |
2239 | if (c == NULL) { | |
2240 | log("channel_open: %d: bad id", id); | |
2241 | return; | |
2242 | } | |
0b242b12 | 2243 | debug("send channel open %d", id); |
7e7327a1 | 2244 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
2245 | packet_put_cstring(c->ctype); | |
2246 | packet_put_int(c->self); | |
2247 | packet_put_int(c->local_window); | |
2248 | packet_put_int(c->local_maxpacket); | |
0b242b12 | 2249 | } |
2250 | void | |
2251 | channel_open(int id) | |
2252 | { | |
2253 | /* XXX REMOVE ME */ | |
2254 | channel_start_open(id); | |
7e7327a1 | 2255 | packet_send(); |
7e7327a1 | 2256 | } |
2257 | void | |
2258 | channel_request(int id, char *service, int wantconfirm) | |
2259 | { | |
2260 | channel_request_start(id, service, wantconfirm); | |
2261 | packet_send(); | |
2262 | debug("channel request %d: %s", id, service) ; | |
2263 | } | |
2264 | void | |
2265 | channel_request_start(int id, char *service, int wantconfirm) | |
2266 | { | |
2267 | Channel *c = channel_lookup(id); | |
2268 | if (c == NULL) { | |
2269 | log("channel_request: %d: bad id", id); | |
2270 | return; | |
2271 | } | |
2272 | packet_start(SSH2_MSG_CHANNEL_REQUEST); | |
2273 | packet_put_int(c->remote_id); | |
2274 | packet_put_cstring(service); | |
2275 | packet_put_char(wantconfirm); | |
2276 | } | |
2277 | void | |
2278 | channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) | |
2279 | { | |
2280 | Channel *c = channel_lookup(id); | |
2281 | if (c == NULL) { | |
2282 | log("channel_register_callback: %d: bad id", id); | |
2283 | return; | |
2284 | } | |
2285 | c->cb_event = mtype; | |
2286 | c->cb_fn = fn; | |
2287 | c->cb_arg = arg; | |
2288 | } | |
2289 | void | |
2290 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
2291 | { | |
2292 | Channel *c = channel_lookup(id); | |
2293 | if (c == NULL) { | |
2294 | log("channel_register_cleanup: %d: bad id", id); | |
2295 | return; | |
2296 | } | |
2297 | c->dettach_user = fn; | |
2298 | } | |
2299 | void | |
2300 | channel_cancel_cleanup(int id) | |
2301 | { | |
2302 | Channel *c = channel_lookup(id); | |
2303 | if (c == NULL) { | |
2304 | log("channel_cancel_cleanup: %d: bad id", id); | |
2305 | return; | |
2306 | } | |
2307 | c->dettach_user = NULL; | |
2308 | } | |
2309 | ||
2310 | void | |
2311 | channel_set_fds(int id, int rfd, int wfd, int efd, int extusage) | |
2312 | { | |
2313 | Channel *c = channel_lookup(id); | |
2314 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) | |
2315 | fatal("channel_activate for non-larval channel %d.", id); | |
0fbe8c74 | 2316 | |
2317 | channel_register_fds(c, rfd, wfd, efd, extusage); | |
7e7327a1 | 2318 | c->type = SSH_CHANNEL_OPEN; |
7e7327a1 | 2319 | /* XXX window size? */ |
2320 | c->local_window = c->local_window_max = c->local_maxpacket/2; | |
2321 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
2322 | packet_put_int(c->remote_id); | |
2323 | packet_put_int(c->local_window); | |
2324 | packet_send(); | |
2325 | } |