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Commit | Line | Data |
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8efc0c15 | 1 | /* |
5260325f | 2 | * |
3 | * channels.c | |
4 | * | |
5 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | |
6 | * | |
7 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
8 | * All rights reserved | |
9 | * | |
10 | * Created: Fri Mar 24 16:35:24 1995 ylo | |
11 | * | |
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. | |
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 | ||
7368a6c8 | 43 | /* default buffer for tcp-fwd-channel */ |
44 | #define CHAN_WINDOW_DEFAULT (8*1024) | |
45 | #define CHAN_PACKET_DEFAULT (CHAN_WINDOW_DEFAULT/2) | |
46 | ||
aa3378df | 47 | /* |
48 | * Pointer to an array containing all allocated channels. The array is | |
49 | * dynamically extended as needed. | |
50 | */ | |
8efc0c15 | 51 | static Channel *channels = NULL; |
52 | ||
aa3378df | 53 | /* |
54 | * Size of the channel array. All slots of the array must always be | |
55 | * initialized (at least the type field); unused slots are marked with type | |
56 | * SSH_CHANNEL_FREE. | |
57 | */ | |
8efc0c15 | 58 | static int channels_alloc = 0; |
59 | ||
aa3378df | 60 | /* |
61 | * Maximum file descriptor value used in any of the channels. This is | |
62 | * updated in channel_allocate. | |
63 | */ | |
8efc0c15 | 64 | static int channel_max_fd_value = 0; |
65 | ||
66 | /* Name and directory of socket for authentication agent forwarding. */ | |
67 | static char *channel_forwarded_auth_socket_name = NULL; | |
5260325f | 68 | static char *channel_forwarded_auth_socket_dir = NULL; |
8efc0c15 | 69 | |
70 | /* Saved X11 authentication protocol name. */ | |
71 | char *x11_saved_proto = NULL; | |
72 | ||
73 | /* Saved X11 authentication data. This is the real data. */ | |
74 | char *x11_saved_data = NULL; | |
75 | unsigned int x11_saved_data_len = 0; | |
76 | ||
aa3378df | 77 | /* |
78 | * Fake X11 authentication data. This is what the server will be sending us; | |
79 | * we should replace any occurrences of this by the real data. | |
80 | */ | |
8efc0c15 | 81 | char *x11_fake_data = NULL; |
82 | unsigned int x11_fake_data_len; | |
83 | ||
aa3378df | 84 | /* |
85 | * Data structure for storing which hosts are permitted for forward requests. | |
86 | * The local sides of any remote forwards are stored in this array to prevent | |
87 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local | |
88 | * network (which might be behind a firewall). | |
89 | */ | |
5260325f | 90 | typedef struct { |
7368a6c8 | 91 | char *host_to_connect; /* Connect to 'host'. */ |
92 | u_short port_to_connect; /* Connect to 'port'. */ | |
93 | u_short listen_port; /* Remote side should listen port number. */ | |
8efc0c15 | 94 | } ForwardPermission; |
95 | ||
96 | /* List of all permitted host/port pairs to connect. */ | |
97 | static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION]; | |
98 | /* Number of permitted host/port pairs in the array. */ | |
99 | static int num_permitted_opens = 0; | |
aa3378df | 100 | /* |
101 | * If this is true, all opens are permitted. This is the case on the server | |
102 | * on which we have to trust the client anyway, and the user could do | |
103 | * anything after logging in anyway. | |
104 | */ | |
8efc0c15 | 105 | static int all_opens_permitted = 0; |
106 | ||
107 | /* This is set to true if both sides support SSH_PROTOFLAG_HOST_IN_FWD_OPEN. */ | |
108 | static int have_hostname_in_open = 0; | |
109 | ||
110 | /* Sets specific protocol options. */ | |
111 | ||
5260325f | 112 | void |
113 | channel_set_options(int hostname_in_open) | |
8efc0c15 | 114 | { |
5260325f | 115 | have_hostname_in_open = hostname_in_open; |
8efc0c15 | 116 | } |
117 | ||
aa3378df | 118 | /* |
119 | * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually | |
120 | * called by the server, because the user could connect to any port anyway, | |
121 | * and the server has no way to know but to trust the client anyway. | |
122 | */ | |
8efc0c15 | 123 | |
5260325f | 124 | void |
125 | channel_permit_all_opens() | |
8efc0c15 | 126 | { |
5260325f | 127 | all_opens_permitted = 1; |
8efc0c15 | 128 | } |
129 | ||
7368a6c8 | 130 | /* lookup channel by id */ |
131 | ||
132 | Channel * | |
133 | channel_lookup(int id) | |
134 | { | |
135 | Channel *c; | |
136 | if (id < 0 && id > channels_alloc) { | |
137 | log("channel_lookup: %d: bad id", id); | |
138 | return NULL; | |
139 | } | |
140 | c = &channels[id]; | |
141 | if (c->type == SSH_CHANNEL_FREE) { | |
142 | log("channel_lookup: %d: bad id: channel free", id); | |
143 | return NULL; | |
144 | } | |
145 | return c; | |
146 | } | |
147 | ||
aa3378df | 148 | /* |
149 | * Allocate a new channel object and set its type and socket. This will cause | |
150 | * remote_name to be freed. | |
151 | */ | |
8efc0c15 | 152 | |
5260325f | 153 | int |
7368a6c8 | 154 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
155 | int window, int maxpack, int extended_usage, char *remote_name) | |
8efc0c15 | 156 | { |
5260325f | 157 | int i, found; |
158 | Channel *c; | |
159 | ||
160 | /* Update the maximum file descriptor value. */ | |
7368a6c8 | 161 | if (rfd > channel_max_fd_value) |
162 | channel_max_fd_value = rfd; | |
163 | if (wfd > channel_max_fd_value) | |
164 | channel_max_fd_value = wfd; | |
165 | if (efd > channel_max_fd_value) | |
166 | channel_max_fd_value = efd; | |
aa3378df | 167 | /* XXX set close-on-exec -markus */ |
5260325f | 168 | |
169 | /* Do initial allocation if this is the first call. */ | |
170 | if (channels_alloc == 0) { | |
7e7327a1 | 171 | chan_init(); |
5260325f | 172 | channels_alloc = 10; |
173 | channels = xmalloc(channels_alloc * sizeof(Channel)); | |
174 | for (i = 0; i < channels_alloc; i++) | |
175 | channels[i].type = SSH_CHANNEL_FREE; | |
aa3378df | 176 | /* |
177 | * Kludge: arrange a call to channel_stop_listening if we | |
178 | * terminate with fatal(). | |
179 | */ | |
5260325f | 180 | fatal_add_cleanup((void (*) (void *)) channel_stop_listening, NULL); |
181 | } | |
182 | /* Try to find a free slot where to put the new channel. */ | |
183 | for (found = -1, i = 0; i < channels_alloc; i++) | |
184 | if (channels[i].type == SSH_CHANNEL_FREE) { | |
185 | /* Found a free slot. */ | |
186 | found = i; | |
187 | break; | |
188 | } | |
189 | if (found == -1) { | |
aa3378df | 190 | /* There are no free slots. Take last+1 slot and expand the array. */ |
5260325f | 191 | found = channels_alloc; |
192 | channels_alloc += 10; | |
193 | debug("channel: expanding %d", channels_alloc); | |
194 | channels = xrealloc(channels, channels_alloc * sizeof(Channel)); | |
195 | for (i = found; i < channels_alloc; i++) | |
196 | channels[i].type = SSH_CHANNEL_FREE; | |
197 | } | |
198 | /* Initialize and return new channel number. */ | |
199 | c = &channels[found]; | |
200 | buffer_init(&c->input); | |
201 | buffer_init(&c->output); | |
7368a6c8 | 202 | buffer_init(&c->extended); |
5260325f | 203 | chan_init_iostates(c); |
204 | c->self = found; | |
205 | c->type = type; | |
7368a6c8 | 206 | c->ctype = ctype; |
207 | c->local_window = window; | |
208 | c->local_window_max = window; | |
209 | c->local_consumed = 0; | |
210 | c->local_maxpacket = maxpack; | |
211 | c->remote_window = 0; | |
212 | c->remote_maxpacket = 0; | |
213 | c->rfd = rfd; | |
214 | c->wfd = wfd; | |
215 | c->sock = (rfd == wfd) ? rfd : -1; | |
216 | c->efd = efd; | |
217 | c->extended_usage = extended_usage; | |
5260325f | 218 | c->remote_id = -1; |
219 | c->remote_name = remote_name; | |
7368a6c8 | 220 | c->remote_window = 0; |
221 | c->remote_maxpacket = 0; | |
222 | c->cb_fn = NULL; | |
223 | c->cb_arg = NULL; | |
224 | c->cb_event = 0; | |
225 | c->dettach_user = NULL; | |
5260325f | 226 | debug("channel %d: new [%s]", found, remote_name); |
227 | return found; | |
8efc0c15 | 228 | } |
7368a6c8 | 229 | int |
230 | channel_allocate(int type, int sock, char *remote_name) | |
231 | { | |
232 | return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name); | |
233 | } | |
8efc0c15 | 234 | |
235 | /* Free the channel and close its socket. */ | |
236 | ||
5260325f | 237 | void |
7368a6c8 | 238 | channel_free(int id) |
8efc0c15 | 239 | { |
7368a6c8 | 240 | Channel *c = channel_lookup(id); |
241 | if (c == NULL) | |
242 | packet_disconnect("channel free: bad local channel %d", id); | |
243 | debug("channel_free: channel %d: status: %s", id, channel_open_message()); | |
7e7327a1 | 244 | if (c->dettach_user != NULL) { |
245 | debug("channel_free: channel %d: dettaching channel user", id); | |
246 | c->dettach_user(c->self, NULL); | |
247 | } | |
7368a6c8 | 248 | if (c->sock != -1) { |
249 | shutdown(c->sock, SHUT_RDWR); | |
250 | close(c->sock); | |
7e7327a1 | 251 | c->sock = -1; |
252 | } | |
253 | if (compat20) { | |
254 | if (c->rfd != -1) { | |
255 | close(c->rfd); | |
256 | c->rfd = -1; | |
257 | } | |
258 | if (c->wfd != -1) { | |
259 | close(c->wfd); | |
260 | c->wfd = -1; | |
261 | } | |
262 | if (c->efd != -1) { | |
263 | close(c->efd); | |
264 | c->efd = -1; | |
265 | } | |
7368a6c8 | 266 | } |
267 | buffer_free(&c->input); | |
268 | buffer_free(&c->output); | |
269 | buffer_free(&c->extended); | |
270 | c->type = SSH_CHANNEL_FREE; | |
271 | if (c->remote_name) { | |
272 | xfree(c->remote_name); | |
273 | c->remote_name = NULL; | |
5260325f | 274 | } |
8efc0c15 | 275 | } |
276 | ||
aa3378df | 277 | /* |
7368a6c8 | 278 | * 'channel_pre*' are called just before select() to add any bits relevant to |
279 | * channels in the select bitmasks. | |
aa3378df | 280 | */ |
7368a6c8 | 281 | /* |
282 | * 'channel_post*': perform any appropriate operations for channels which | |
283 | * have events pending. | |
284 | */ | |
285 | typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset); | |
286 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; | |
287 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; | |
8efc0c15 | 288 | |
7368a6c8 | 289 | void |
290 | channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
8efc0c15 | 291 | { |
7368a6c8 | 292 | FD_SET(c->sock, readset); |
293 | } | |
5260325f | 294 | |
7368a6c8 | 295 | void |
296 | channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset) | |
297 | { | |
298 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
299 | FD_SET(c->sock, readset); | |
300 | if (buffer_len(&c->output) > 0) | |
301 | FD_SET(c->sock, writeset); | |
302 | } | |
5260325f | 303 | |
7368a6c8 | 304 | void |
305 | channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset) | |
306 | { | |
307 | /* test whether sockets are 'alive' for read/write */ | |
308 | if (c->istate == CHAN_INPUT_OPEN) | |
309 | if (buffer_len(&c->input) < packet_get_maxsize()) | |
310 | FD_SET(c->sock, readset); | |
311 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
312 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
313 | if (buffer_len(&c->output) > 0) { | |
314 | FD_SET(c->sock, writeset); | |
315 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
316 | chan_obuf_empty(c); | |
317 | } | |
318 | } | |
319 | } | |
5260325f | 320 | |
7e7327a1 | 321 | void |
322 | channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset) | |
323 | { | |
324 | if (c->istate == CHAN_INPUT_OPEN && | |
325 | c->remote_window > 0 && | |
326 | buffer_len(&c->input) < c->remote_window) | |
327 | FD_SET(c->rfd, readset); | |
328 | if (c->ostate == CHAN_OUTPUT_OPEN || | |
329 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
330 | if (buffer_len(&c->output) > 0) { | |
331 | FD_SET(c->wfd, writeset); | |
332 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { | |
333 | chan_obuf_empty(c); | |
334 | } | |
335 | } | |
336 | /** XXX check close conditions, too */ | |
337 | if (c->efd != -1) { | |
338 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
339 | buffer_len(&c->extended) > 0) | |
340 | FD_SET(c->efd, writeset); | |
341 | else if (c->extended_usage == CHAN_EXTENDED_READ && | |
342 | buffer_len(&c->extended) < c->remote_window) | |
343 | FD_SET(c->efd, readset); | |
344 | } | |
345 | } | |
346 | ||
7368a6c8 | 347 | void |
348 | channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset) | |
349 | { | |
350 | if (buffer_len(&c->input) == 0) { | |
351 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
352 | packet_put_int(c->remote_id); | |
353 | packet_send(); | |
354 | c->type = SSH_CHANNEL_CLOSED; | |
355 | debug("Closing channel %d after input drain.", c->self); | |
356 | } | |
357 | } | |
5260325f | 358 | |
7368a6c8 | 359 | void |
360 | channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset) | |
361 | { | |
362 | if (buffer_len(&c->output) == 0) | |
363 | channel_free(c->self); | |
364 | else | |
365 | FD_SET(c->sock, writeset); | |
366 | } | |
5260325f | 367 | |
7368a6c8 | 368 | /* |
369 | * This is a special state for X11 authentication spoofing. An opened X11 | |
370 | * connection (when authentication spoofing is being done) remains in this | |
371 | * state until the first packet has been completely read. The authentication | |
372 | * data in that packet is then substituted by the real data if it matches the | |
373 | * fake data, and the channel is put into normal mode. | |
374 | */ | |
375 | int | |
376 | x11_open_helper(Channel *c) | |
377 | { | |
378 | unsigned char *ucp; | |
379 | unsigned int proto_len, data_len; | |
5260325f | 380 | |
7368a6c8 | 381 | /* Check if the fixed size part of the packet is in buffer. */ |
382 | if (buffer_len(&c->output) < 12) | |
383 | return 0; | |
384 | ||
385 | /* Parse the lengths of variable-length fields. */ | |
386 | ucp = (unsigned char *) buffer_ptr(&c->output); | |
387 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ | |
388 | proto_len = 256 * ucp[6] + ucp[7]; | |
389 | data_len = 256 * ucp[8] + ucp[9]; | |
390 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ | |
391 | proto_len = ucp[6] + 256 * ucp[7]; | |
392 | data_len = ucp[8] + 256 * ucp[9]; | |
393 | } else { | |
394 | debug("Initial X11 packet contains bad byte order byte: 0x%x", | |
395 | ucp[0]); | |
396 | return -1; | |
397 | } | |
5260325f | 398 | |
7368a6c8 | 399 | /* Check if the whole packet is in buffer. */ |
400 | if (buffer_len(&c->output) < | |
401 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) | |
402 | return 0; | |
5260325f | 403 | |
7368a6c8 | 404 | /* Check if authentication protocol matches. */ |
405 | if (proto_len != strlen(x11_saved_proto) || | |
406 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { | |
407 | debug("X11 connection uses different authentication protocol."); | |
408 | return -1; | |
409 | } | |
410 | /* Check if authentication data matches our fake data. */ | |
411 | if (data_len != x11_fake_data_len || | |
412 | memcmp(ucp + 12 + ((proto_len + 3) & ~3), | |
413 | x11_fake_data, x11_fake_data_len) != 0) { | |
414 | debug("X11 auth data does not match fake data."); | |
415 | return -1; | |
416 | } | |
417 | /* Check fake data length */ | |
418 | if (x11_fake_data_len != x11_saved_data_len) { | |
419 | error("X11 fake_data_len %d != saved_data_len %d", | |
420 | x11_fake_data_len, x11_saved_data_len); | |
421 | return -1; | |
422 | } | |
423 | /* | |
424 | * Received authentication protocol and data match | |
425 | * our fake data. Substitute the fake data with real | |
426 | * data. | |
427 | */ | |
428 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), | |
429 | x11_saved_data, x11_saved_data_len); | |
430 | return 1; | |
431 | } | |
5260325f | 432 | |
7368a6c8 | 433 | void |
434 | channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset) | |
435 | { | |
436 | int ret = x11_open_helper(c); | |
437 | if (ret == 1) { | |
438 | /* Start normal processing for the channel. */ | |
439 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 440 | channel_pre_open_13(c, readset, writeset); |
7368a6c8 | 441 | } else if (ret == -1) { |
442 | /* | |
443 | * We have received an X11 connection that has bad | |
444 | * authentication information. | |
445 | */ | |
446 | log("X11 connection rejected because of wrong authentication.\r\n"); | |
447 | buffer_clear(&c->input); | |
448 | buffer_clear(&c->output); | |
449 | close(c->sock); | |
450 | c->sock = -1; | |
451 | c->type = SSH_CHANNEL_CLOSED; | |
452 | packet_start(SSH_MSG_CHANNEL_CLOSE); | |
453 | packet_put_int(c->remote_id); | |
454 | packet_send(); | |
455 | } | |
456 | } | |
5260325f | 457 | |
7368a6c8 | 458 | void |
459 | channel_pre_x11_open_15(Channel *c, fd_set * readset, fd_set * writeset) | |
460 | { | |
461 | int ret = x11_open_helper(c); | |
462 | if (ret == 1) { | |
463 | c->type = SSH_CHANNEL_OPEN; | |
a8be9f80 | 464 | channel_pre_open_15(c, readset, writeset); |
7368a6c8 | 465 | } else if (ret == -1) { |
466 | debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); | |
467 | chan_read_failed(c); | |
468 | chan_write_failed(c); | |
469 | debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); | |
470 | } | |
471 | } | |
5260325f | 472 | |
7368a6c8 | 473 | /* This is our fake X11 server socket. */ |
474 | void | |
475 | channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
476 | { | |
477 | struct sockaddr addr; | |
478 | int newsock, newch; | |
479 | socklen_t addrlen; | |
480 | char buf[16384], *remote_hostname; | |
481 | ||
482 | if (FD_ISSET(c->sock, readset)) { | |
483 | debug("X11 connection requested."); | |
484 | addrlen = sizeof(addr); | |
485 | newsock = accept(c->sock, &addr, &addrlen); | |
486 | if (newsock < 0) { | |
487 | error("accept: %.100s", strerror(errno)); | |
488 | return; | |
5260325f | 489 | } |
7368a6c8 | 490 | remote_hostname = get_remote_hostname(newsock); |
491 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", | |
492 | remote_hostname, get_peer_port(newsock)); | |
493 | xfree(remote_hostname); | |
494 | newch = channel_allocate(SSH_CHANNEL_OPENING, newsock, | |
495 | xstrdup(buf)); | |
496 | packet_start(SSH_SMSG_X11_OPEN); | |
497 | packet_put_int(newch); | |
498 | if (have_hostname_in_open) | |
499 | packet_put_string(buf, strlen(buf)); | |
500 | packet_send(); | |
8efc0c15 | 501 | } |
8efc0c15 | 502 | } |
503 | ||
aa3378df | 504 | /* |
7368a6c8 | 505 | * This socket is listening for connections to a forwarded TCP/IP port. |
aa3378df | 506 | */ |
7368a6c8 | 507 | void |
508 | channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
509 | { | |
510 | struct sockaddr addr; | |
511 | int newsock, newch; | |
512 | socklen_t addrlen; | |
513 | char buf[1024], *remote_hostname; | |
514 | int remote_port; | |
515 | ||
516 | if (FD_ISSET(c->sock, readset)) { | |
517 | debug("Connection to port %d forwarding " | |
518 | "to %.100s port %d requested.", | |
519 | c->listening_port, c->path, c->host_port); | |
520 | addrlen = sizeof(addr); | |
521 | newsock = accept(c->sock, &addr, &addrlen); | |
522 | if (newsock < 0) { | |
523 | error("accept: %.100s", strerror(errno)); | |
524 | return; | |
525 | } | |
526 | remote_hostname = get_remote_hostname(newsock); | |
527 | remote_port = get_peer_port(newsock); | |
528 | snprintf(buf, sizeof buf, | |
529 | "listen port %d for %.100s port %d, " | |
530 | "connect from %.200s port %d", | |
531 | c->listening_port, c->path, c->host_port, | |
532 | remote_hostname, remote_port); | |
533 | newch = channel_new("direct-tcpip", | |
534 | SSH_CHANNEL_OPENING, newsock, newsock, -1, | |
535 | c->local_window_max, c->local_maxpacket, | |
536 | 0, xstrdup(buf)); | |
7e7327a1 | 537 | if (compat20) { |
538 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
539 | packet_put_cstring("direct-tcpip"); | |
540 | packet_put_int(newch); | |
541 | packet_put_int(c->local_window_max); | |
542 | packet_put_int(c->local_maxpacket); | |
543 | packet_put_string(c->path, strlen(c->path)); | |
544 | packet_put_int(c->host_port); | |
545 | packet_put_cstring(remote_hostname); | |
546 | packet_put_int(remote_port); | |
547 | packet_send(); | |
548 | } else { | |
549 | packet_start(SSH_MSG_PORT_OPEN); | |
550 | packet_put_int(newch); | |
551 | packet_put_string(c->path, strlen(c->path)); | |
552 | packet_put_int(c->host_port); | |
553 | if (have_hostname_in_open) { | |
554 | packet_put_string(buf, strlen(buf)); | |
555 | } | |
556 | packet_send(); | |
7368a6c8 | 557 | } |
7368a6c8 | 558 | xfree(remote_hostname); |
559 | } | |
560 | } | |
8efc0c15 | 561 | |
7368a6c8 | 562 | /* |
563 | * This is the authentication agent socket listening for connections from | |
564 | * clients. | |
565 | */ | |
566 | void | |
567 | channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset) | |
8efc0c15 | 568 | { |
5260325f | 569 | struct sockaddr addr; |
7368a6c8 | 570 | int newsock, newch; |
48e671d5 | 571 | socklen_t addrlen; |
5260325f | 572 | |
7368a6c8 | 573 | if (FD_ISSET(c->sock, readset)) { |
574 | addrlen = sizeof(addr); | |
575 | newsock = accept(c->sock, &addr, &addrlen); | |
576 | if (newsock < 0) { | |
577 | error("accept from auth socket: %.100s", strerror(errno)); | |
578 | return; | |
579 | } | |
580 | newch = channel_allocate(SSH_CHANNEL_OPENING, newsock, | |
581 | xstrdup("accepted auth socket")); | |
582 | packet_start(SSH_SMSG_AGENT_OPEN); | |
583 | packet_put_int(newch); | |
584 | packet_send(); | |
585 | } | |
586 | } | |
5260325f | 587 | |
7368a6c8 | 588 | int |
589 | channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset) | |
590 | { | |
591 | char buf[16*1024]; | |
592 | int len; | |
593 | ||
594 | if (c->rfd != -1 && | |
595 | FD_ISSET(c->rfd, readset)) { | |
596 | len = read(c->rfd, buf, sizeof(buf)); | |
597 | if (len <= 0) { | |
598 | debug("channel %d: read<0 rfd %d len %d", | |
599 | c->self, c->rfd, len); | |
600 | if (compat13) { | |
601 | buffer_consume(&c->output, buffer_len(&c->output)); | |
602 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
603 | debug("Channel %d status set to input draining.", c->self); | |
604 | } else { | |
605 | chan_read_failed(c); | |
5260325f | 606 | } |
7368a6c8 | 607 | return -1; |
608 | } | |
609 | buffer_append(&c->input, buf, len); | |
610 | } | |
611 | return 1; | |
612 | } | |
613 | int | |
614 | channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset) | |
615 | { | |
616 | int len; | |
617 | ||
618 | /* Send buffered output data to the socket. */ | |
619 | if (c->wfd != -1 && | |
620 | FD_ISSET(c->wfd, writeset) && | |
621 | buffer_len(&c->output) > 0) { | |
622 | len = write(c->wfd, buffer_ptr(&c->output), | |
623 | buffer_len(&c->output)); | |
624 | if (len <= 0) { | |
625 | if (compat13) { | |
626 | buffer_consume(&c->output, buffer_len(&c->output)); | |
627 | debug("Channel %d status set to input draining.", c->self); | |
628 | c->type = SSH_CHANNEL_INPUT_DRAINING; | |
629 | } else { | |
630 | chan_write_failed(c); | |
5260325f | 631 | } |
7368a6c8 | 632 | return -1; |
633 | } | |
634 | buffer_consume(&c->output, len); | |
7e7327a1 | 635 | if (compat20 && len > 0) { |
636 | c->local_consumed += len; | |
637 | } | |
638 | } | |
639 | return 1; | |
640 | } | |
641 | int | |
642 | channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset) | |
643 | { | |
644 | char buf[16*1024]; | |
645 | int len; | |
646 | ||
8ce64345 | 647 | /** XXX handle drain efd, too */ |
7e7327a1 | 648 | if (c->efd != -1) { |
649 | if (c->extended_usage == CHAN_EXTENDED_WRITE && | |
650 | FD_ISSET(c->efd, writeset) && | |
651 | buffer_len(&c->extended) > 0) { | |
652 | len = write(c->efd, buffer_ptr(&c->extended), | |
653 | buffer_len(&c->extended)); | |
654 | debug("channel %d: written %d to efd %d", | |
655 | c->self, len, c->efd); | |
656 | if (len > 0) { | |
657 | buffer_consume(&c->extended, len); | |
658 | c->local_consumed += len; | |
659 | } | |
660 | } else if (c->extended_usage == CHAN_EXTENDED_READ && | |
661 | FD_ISSET(c->efd, readset)) { | |
662 | len = read(c->efd, buf, sizeof(buf)); | |
663 | debug("channel %d: read %d from efd %d", | |
664 | c->self, len, c->efd); | |
8ce64345 | 665 | if (len == 0) { |
666 | debug("channel %d: closing efd %d", | |
667 | c->self, c->efd); | |
668 | close(c->efd); | |
669 | c->efd = -1; | |
670 | } else if (len > 0) | |
7e7327a1 | 671 | buffer_append(&c->extended, buf, len); |
672 | } | |
673 | } | |
674 | return 1; | |
675 | } | |
676 | int | |
677 | channel_check_window(Channel *c, fd_set * readset, fd_set * writeset) | |
678 | { | |
e78a59f5 | 679 | if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && |
7e7327a1 | 680 | c->local_window < c->local_window_max/2 && |
681 | c->local_consumed > 0) { | |
682 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
683 | packet_put_int(c->remote_id); | |
684 | packet_put_int(c->local_consumed); | |
685 | packet_send(); | |
686 | debug("channel %d: window %d sent adjust %d", | |
687 | c->self, c->local_window, | |
688 | c->local_consumed); | |
689 | c->local_window += c->local_consumed; | |
690 | c->local_consumed = 0; | |
7368a6c8 | 691 | } |
692 | return 1; | |
693 | } | |
5260325f | 694 | |
7368a6c8 | 695 | void |
696 | channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset) | |
697 | { | |
698 | channel_handle_rfd(c, readset, writeset); | |
699 | channel_handle_wfd(c, readset, writeset); | |
700 | } | |
aa3378df | 701 | |
7e7327a1 | 702 | void |
703 | channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset) | |
704 | { | |
705 | channel_handle_rfd(c, readset, writeset); | |
706 | channel_handle_wfd(c, readset, writeset); | |
707 | channel_handle_efd(c, readset, writeset); | |
708 | channel_check_window(c, readset, writeset); | |
709 | } | |
710 | ||
7368a6c8 | 711 | void |
712 | channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset) | |
713 | { | |
714 | int len; | |
715 | /* Send buffered output data to the socket. */ | |
716 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { | |
717 | len = write(c->sock, buffer_ptr(&c->output), | |
718 | buffer_len(&c->output)); | |
719 | if (len <= 0) | |
720 | buffer_consume(&c->output, buffer_len(&c->output)); | |
721 | else | |
722 | buffer_consume(&c->output, len); | |
723 | } | |
724 | } | |
5260325f | 725 | |
7e7327a1 | 726 | void |
727 | channel_handler_init_20(void) | |
728 | { | |
729 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20; | |
730 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
731 | ||
732 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2; | |
733 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
734 | } | |
735 | ||
7368a6c8 | 736 | void |
737 | channel_handler_init_13(void) | |
738 | { | |
739 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; | |
740 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; | |
741 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
742 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
743 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
744 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; | |
745 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; | |
746 | ||
747 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
748 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
749 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
750 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
751 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; | |
752 | } | |
5260325f | 753 | |
7368a6c8 | 754 | void |
755 | channel_handler_init_15(void) | |
756 | { | |
757 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15; | |
758 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_15; | |
759 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; | |
760 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; | |
761 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; | |
762 | ||
763 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; | |
764 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; | |
765 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; | |
766 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1; | |
767 | } | |
768 | ||
769 | void | |
770 | channel_handler_init(void) | |
771 | { | |
772 | int i; | |
773 | for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { | |
774 | channel_pre[i] = NULL; | |
775 | channel_post[i] = NULL; | |
776 | } | |
7e7327a1 | 777 | if (compat20) |
778 | channel_handler_init_20(); | |
779 | else if (compat13) | |
7368a6c8 | 780 | channel_handler_init_13(); |
781 | else | |
782 | channel_handler_init_15(); | |
783 | } | |
784 | ||
785 | void | |
786 | channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset) | |
787 | { | |
788 | static int did_init = 0; | |
789 | int i; | |
790 | Channel *c; | |
791 | ||
792 | if (!did_init) { | |
793 | channel_handler_init(); | |
794 | did_init = 1; | |
795 | } | |
796 | for (i = 0; i < channels_alloc; i++) { | |
797 | c = &channels[i]; | |
798 | if (c->type == SSH_CHANNEL_FREE) | |
5260325f | 799 | continue; |
7368a6c8 | 800 | if (ftab[c->type] == NULL) |
801 | continue; | |
802 | (*ftab[c->type])(c, readset, writeset); | |
7e7327a1 | 803 | chan_delete_if_full_closed(c); |
8efc0c15 | 804 | } |
8efc0c15 | 805 | } |
806 | ||
7368a6c8 | 807 | void |
808 | channel_prepare_select(fd_set * readset, fd_set * writeset) | |
809 | { | |
810 | channel_handler(channel_pre, readset, writeset); | |
811 | } | |
812 | ||
813 | void | |
814 | channel_after_select(fd_set * readset, fd_set * writeset) | |
815 | { | |
816 | channel_handler(channel_post, readset, writeset); | |
817 | } | |
818 | ||
8efc0c15 | 819 | /* If there is data to send to the connection, send some of it now. */ |
820 | ||
5260325f | 821 | void |
822 | channel_output_poll() | |
8efc0c15 | 823 | { |
5260325f | 824 | int len, i; |
7368a6c8 | 825 | Channel *c; |
5260325f | 826 | |
827 | for (i = 0; i < channels_alloc; i++) { | |
7368a6c8 | 828 | c = &channels[i]; |
48e671d5 | 829 | |
aa3378df | 830 | /* We are only interested in channels that can have buffered incoming data. */ |
48e671d5 | 831 | if (compat13) { |
7368a6c8 | 832 | if (c->type != SSH_CHANNEL_OPEN && |
833 | c->type != SSH_CHANNEL_INPUT_DRAINING) | |
48e671d5 | 834 | continue; |
835 | } else { | |
7368a6c8 | 836 | if (c->type != SSH_CHANNEL_OPEN) |
48e671d5 | 837 | continue; |
7368a6c8 | 838 | if (c->istate != CHAN_INPUT_OPEN && |
839 | c->istate != CHAN_INPUT_WAIT_DRAIN) | |
48e671d5 | 840 | continue; |
841 | } | |
e78a59f5 | 842 | if (compat20 && |
843 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { | |
7e7327a1 | 844 | debug("channel: %d: no data after CLOSE", c->self); |
845 | continue; | |
846 | } | |
5260325f | 847 | |
848 | /* Get the amount of buffered data for this channel. */ | |
7368a6c8 | 849 | len = buffer_len(&c->input); |
5260325f | 850 | if (len > 0) { |
aa3378df | 851 | /* Send some data for the other side over the secure connection. */ |
7e7327a1 | 852 | if (compat20) { |
853 | if (len > c->remote_window) | |
854 | len = c->remote_window; | |
855 | if (len > c->remote_maxpacket) | |
856 | len = c->remote_maxpacket; | |
5260325f | 857 | } else { |
7e7327a1 | 858 | if (packet_is_interactive()) { |
859 | if (len > 1024) | |
860 | len = 512; | |
861 | } else { | |
862 | /* Keep the packets at reasonable size. */ | |
863 | if (len > packet_get_maxsize()/2) | |
864 | len = packet_get_maxsize()/2; | |
865 | } | |
5260325f | 866 | } |
7368a6c8 | 867 | if (len > 0) { |
7e7327a1 | 868 | packet_start(compat20 ? |
869 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); | |
7368a6c8 | 870 | packet_put_int(c->remote_id); |
871 | packet_put_string(buffer_ptr(&c->input), len); | |
872 | packet_send(); | |
873 | buffer_consume(&c->input, len); | |
874 | c->remote_window -= len; | |
7e7327a1 | 875 | debug("channel %d: send data len %d", c->self, len); |
7368a6c8 | 876 | } |
877 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { | |
5260325f | 878 | if (compat13) |
879 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); | |
aa3378df | 880 | /* |
881 | * input-buffer is empty and read-socket shutdown: | |
882 | * tell peer, that we will not send more data: send IEOF | |
883 | */ | |
7368a6c8 | 884 | chan_ibuf_empty(c); |
5260325f | 885 | } |
7e7327a1 | 886 | /* Send extended data, i.e. stderr */ |
887 | if (compat20 && | |
888 | c->remote_window > 0 && | |
889 | (len = buffer_len(&c->extended)) > 0 && | |
890 | c->extended_usage == CHAN_EXTENDED_READ) { | |
891 | if (len > c->remote_window) | |
892 | len = c->remote_window; | |
893 | if (len > c->remote_maxpacket) | |
894 | len = c->remote_maxpacket; | |
895 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); | |
896 | packet_put_int(c->remote_id); | |
897 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); | |
898 | packet_put_string(buffer_ptr(&c->extended), len); | |
899 | packet_send(); | |
900 | buffer_consume(&c->extended, len); | |
901 | c->remote_window -= len; | |
902 | } | |
8efc0c15 | 903 | } |
8efc0c15 | 904 | } |
905 | ||
aa3378df | 906 | /* |
907 | * This is called when a packet of type CHANNEL_DATA has just been received. | |
908 | * The message type has already been consumed, but channel number and data is | |
909 | * still there. | |
910 | */ | |
8efc0c15 | 911 | |
5260325f | 912 | void |
7368a6c8 | 913 | channel_input_data(int type, int plen) |
8efc0c15 | 914 | { |
48e671d5 | 915 | int id; |
5260325f | 916 | char *data; |
917 | unsigned int data_len; | |
7368a6c8 | 918 | Channel *c; |
5260325f | 919 | |
920 | /* Get the channel number and verify it. */ | |
48e671d5 | 921 | id = packet_get_int(); |
7368a6c8 | 922 | c = channel_lookup(id); |
923 | if (c == NULL) | |
48e671d5 | 924 | packet_disconnect("Received data for nonexistent channel %d.", id); |
5260325f | 925 | |
926 | /* Ignore any data for non-open channels (might happen on close) */ | |
7368a6c8 | 927 | if (c->type != SSH_CHANNEL_OPEN && |
928 | c->type != SSH_CHANNEL_X11_OPEN) | |
48e671d5 | 929 | return; |
930 | ||
931 | /* same for protocol 1.5 if output end is no longer open */ | |
7368a6c8 | 932 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) |
5260325f | 933 | return; |
934 | ||
935 | /* Get the data. */ | |
936 | data = packet_get_string(&data_len); | |
7368a6c8 | 937 | |
7e7327a1 | 938 | if (compat20){ |
939 | if (data_len > c->local_maxpacket) { | |
940 | log("channel %d: rcvd big packet %d, maxpack %d", | |
941 | c->self, data_len, c->local_maxpacket); | |
942 | } | |
943 | if (data_len > c->local_window) { | |
944 | log("channel %d: rcvd too much data %d, win %d", | |
945 | c->self, data_len, c->local_window); | |
946 | xfree(data); | |
947 | return; | |
948 | } | |
949 | c->local_window -= data_len; | |
950 | }else{ | |
951 | packet_integrity_check(plen, 4 + 4 + data_len, type); | |
952 | } | |
7368a6c8 | 953 | buffer_append(&c->output, data, data_len); |
5260325f | 954 | xfree(data); |
8efc0c15 | 955 | } |
7e7327a1 | 956 | void |
957 | channel_input_extended_data(int type, int plen) | |
958 | { | |
959 | int id; | |
960 | int tcode; | |
961 | char *data; | |
962 | unsigned int data_len; | |
963 | Channel *c; | |
964 | ||
965 | /* Get the channel number and verify it. */ | |
966 | id = packet_get_int(); | |
967 | c = channel_lookup(id); | |
968 | ||
969 | if (c == NULL) | |
970 | packet_disconnect("Received extended_data for bad channel %d.", id); | |
971 | if (c->type != SSH_CHANNEL_OPEN) { | |
972 | log("channel %d: ext data for non open", id); | |
973 | return; | |
974 | } | |
975 | tcode = packet_get_int(); | |
976 | if (c->efd == -1 || | |
977 | c->extended_usage != CHAN_EXTENDED_WRITE || | |
978 | tcode != SSH2_EXTENDED_DATA_STDERR) { | |
979 | log("channel %d: bad ext data", c->self); | |
980 | return; | |
981 | } | |
982 | data = packet_get_string(&data_len); | |
983 | if (data_len > c->local_window) { | |
984 | log("channel %d: rcvd too much extended_data %d, win %d", | |
985 | c->self, data_len, c->local_window); | |
986 | xfree(data); | |
987 | return; | |
988 | } | |
989 | debug("channel %d: rcvd ext data %d", c->self, data_len); | |
990 | c->local_window -= data_len; | |
991 | buffer_append(&c->extended, data, data_len); | |
992 | xfree(data); | |
993 | } | |
994 | ||
8efc0c15 | 995 | |
aa3378df | 996 | /* |
997 | * Returns true if no channel has too much buffered data, and false if one or | |
998 | * more channel is overfull. | |
999 | */ | |
8efc0c15 | 1000 | |
5260325f | 1001 | int |
1002 | channel_not_very_much_buffered_data() | |
8efc0c15 | 1003 | { |
5260325f | 1004 | unsigned int i; |
7368a6c8 | 1005 | Channel *c; |
5260325f | 1006 | |
1007 | for (i = 0; i < channels_alloc; i++) { | |
7368a6c8 | 1008 | c = &channels[i]; |
1009 | if (c->type == SSH_CHANNEL_OPEN) { | |
7e7327a1 | 1010 | if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) { |
7368a6c8 | 1011 | debug("channel %d: big input buffer %d", |
1012 | c->self, buffer_len(&c->input)); | |
5260325f | 1013 | return 0; |
7368a6c8 | 1014 | } |
1015 | if (buffer_len(&c->output) > packet_get_maxsize()) { | |
1016 | debug("channel %d: big output buffer %d", | |
1017 | c->self, buffer_len(&c->output)); | |
5260325f | 1018 | return 0; |
7368a6c8 | 1019 | } |
5260325f | 1020 | } |
8efc0c15 | 1021 | } |
5260325f | 1022 | return 1; |
8efc0c15 | 1023 | } |
1024 | ||
7368a6c8 | 1025 | void |
1026 | channel_input_ieof(int type, int plen) | |
1027 | { | |
1028 | int id; | |
1029 | Channel *c; | |
1030 | ||
1031 | packet_integrity_check(plen, 4, type); | |
1032 | ||
1033 | id = packet_get_int(); | |
1034 | c = channel_lookup(id); | |
1035 | if (c == NULL) | |
1036 | packet_disconnect("Received ieof for nonexistent channel %d.", id); | |
1037 | chan_rcvd_ieof(c); | |
1038 | } | |
8efc0c15 | 1039 | |
5260325f | 1040 | void |
7368a6c8 | 1041 | channel_input_close(int type, int plen) |
8efc0c15 | 1042 | { |
7368a6c8 | 1043 | int id; |
1044 | Channel *c; | |
5260325f | 1045 | |
7368a6c8 | 1046 | packet_integrity_check(plen, 4, type); |
1047 | ||
1048 | id = packet_get_int(); | |
1049 | c = channel_lookup(id); | |
1050 | if (c == NULL) | |
1051 | packet_disconnect("Received close for nonexistent channel %d.", id); | |
aa3378df | 1052 | |
1053 | /* | |
1054 | * Send a confirmation that we have closed the channel and no more | |
1055 | * data is coming for it. | |
1056 | */ | |
5260325f | 1057 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
7368a6c8 | 1058 | packet_put_int(c->remote_id); |
5260325f | 1059 | packet_send(); |
1060 | ||
aa3378df | 1061 | /* |
1062 | * If the channel is in closed state, we have sent a close request, | |
1063 | * and the other side will eventually respond with a confirmation. | |
1064 | * Thus, we cannot free the channel here, because then there would be | |
1065 | * no-one to receive the confirmation. The channel gets freed when | |
1066 | * the confirmation arrives. | |
1067 | */ | |
7368a6c8 | 1068 | if (c->type != SSH_CHANNEL_CLOSED) { |
aa3378df | 1069 | /* |
1070 | * Not a closed channel - mark it as draining, which will | |
1071 | * cause it to be freed later. | |
1072 | */ | |
7368a6c8 | 1073 | buffer_consume(&c->input, buffer_len(&c->input)); |
1074 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; | |
5260325f | 1075 | } |
8efc0c15 | 1076 | } |
1077 | ||
7368a6c8 | 1078 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
5260325f | 1079 | void |
7368a6c8 | 1080 | channel_input_oclose(int type, int plen) |
8efc0c15 | 1081 | { |
7368a6c8 | 1082 | int id = packet_get_int(); |
1083 | Channel *c = channel_lookup(id); | |
1084 | packet_integrity_check(plen, 4, type); | |
1085 | if (c == NULL) | |
1086 | packet_disconnect("Received oclose for nonexistent channel %d.", id); | |
1087 | chan_rcvd_oclose(c); | |
8efc0c15 | 1088 | } |
1089 | ||
7368a6c8 | 1090 | void |
1091 | channel_input_close_confirmation(int type, int plen) | |
1092 | { | |
1093 | int id = packet_get_int(); | |
1094 | Channel *c = channel_lookup(id); | |
1095 | ||
1096 | if (c == NULL) | |
1097 | packet_disconnect("Received close confirmation for " | |
1098 | "out-of-range channel %d.", id); | |
1099 | if (c->type != SSH_CHANNEL_CLOSED) | |
1100 | packet_disconnect("Received close confirmation for " | |
1101 | "non-closed channel %d (type %d).", id, c->type); | |
1102 | channel_free(c->self); | |
1103 | } | |
8efc0c15 | 1104 | |
5260325f | 1105 | void |
7368a6c8 | 1106 | channel_input_open_confirmation(int type, int plen) |
8efc0c15 | 1107 | { |
7368a6c8 | 1108 | int id, remote_id; |
1109 | Channel *c; | |
5260325f | 1110 | |
7e7327a1 | 1111 | if (!compat20) |
1112 | packet_integrity_check(plen, 4 + 4, type); | |
5260325f | 1113 | |
7368a6c8 | 1114 | id = packet_get_int(); |
1115 | c = channel_lookup(id); | |
5260325f | 1116 | |
7368a6c8 | 1117 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) |
1118 | packet_disconnect("Received open confirmation for " | |
1119 | "non-opening channel %d.", id); | |
1120 | remote_id = packet_get_int(); | |
aa3378df | 1121 | /* Record the remote channel number and mark that the channel is now open. */ |
7368a6c8 | 1122 | c->remote_id = remote_id; |
1123 | c->type = SSH_CHANNEL_OPEN; | |
7e7327a1 | 1124 | |
1125 | if (compat20) { | |
1126 | c->remote_window = packet_get_int(); | |
1127 | c->remote_maxpacket = packet_get_int(); | |
1128 | if (c->cb_fn != NULL && c->cb_event == type) { | |
1129 | debug("callback start"); | |
1130 | c->cb_fn(c->self, c->cb_arg); | |
1131 | debug("callback done"); | |
1132 | } | |
1133 | debug("channel %d: open confirm rwindow %d rmax %d", c->self, | |
1134 | c->remote_window, c->remote_maxpacket); | |
1135 | } | |
8efc0c15 | 1136 | } |
1137 | ||
5260325f | 1138 | void |
7368a6c8 | 1139 | channel_input_open_failure(int type, int plen) |
8efc0c15 | 1140 | { |
7368a6c8 | 1141 | int id; |
1142 | Channel *c; | |
5260325f | 1143 | |
7e7327a1 | 1144 | if (!compat20) |
1145 | packet_integrity_check(plen, 4, type); | |
7368a6c8 | 1146 | |
1147 | id = packet_get_int(); | |
1148 | c = channel_lookup(id); | |
1149 | ||
1150 | if (c==NULL || c->type != SSH_CHANNEL_OPENING) | |
1151 | packet_disconnect("Received open failure for " | |
1152 | "non-opening channel %d.", id); | |
7e7327a1 | 1153 | if (compat20) { |
1154 | int reason = packet_get_int(); | |
1155 | char *msg = packet_get_string(NULL); | |
1156 | log("channel_open_failure: %d: reason %d: %s", id, reason, msg); | |
1157 | xfree(msg); | |
1158 | } | |
5260325f | 1159 | /* Free the channel. This will also close the socket. */ |
7368a6c8 | 1160 | channel_free(id); |
8efc0c15 | 1161 | } |
1162 | ||
7e7327a1 | 1163 | void |
1164 | channel_input_channel_request(int type, int plen) | |
1165 | { | |
1166 | int id; | |
1167 | Channel *c; | |
1168 | ||
1169 | id = packet_get_int(); | |
1170 | c = channel_lookup(id); | |
1171 | ||
1172 | if (c == NULL || | |
1173 | (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL)) | |
1174 | packet_disconnect("Received request for " | |
1175 | "non-open channel %d.", id); | |
1176 | if (c->cb_fn != NULL && c->cb_event == type) { | |
1177 | debug("callback start"); | |
1178 | c->cb_fn(c->self, c->cb_arg); | |
1179 | debug("callback done"); | |
1180 | } else { | |
1181 | char *service = packet_get_string(NULL); | |
1182 | debug("channel: %d rcvd request for %s", c->self, service); | |
1183 | debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event); | |
1184 | xfree(service); | |
1185 | } | |
1186 | } | |
1187 | ||
1188 | void | |
1189 | channel_input_window_adjust(int type, int plen) | |
1190 | { | |
1191 | Channel *c; | |
1192 | int id, adjust; | |
1193 | ||
1194 | if (!compat20) | |
1195 | return; | |
1196 | ||
1197 | /* Get the channel number and verify it. */ | |
1198 | id = packet_get_int(); | |
1199 | c = channel_lookup(id); | |
1200 | ||
1201 | if (c == NULL || c->type != SSH_CHANNEL_OPEN) { | |
1202 | log("Received window adjust for " | |
1203 | "non-open channel %d.", id); | |
1204 | return; | |
1205 | } | |
1206 | adjust = packet_get_int(); | |
1207 | debug("channel %d: rcvd adjust %d", id, adjust); | |
1208 | c->remote_window += adjust; | |
1209 | } | |
1210 | ||
aa3378df | 1211 | /* |
1212 | * Stops listening for channels, and removes any unix domain sockets that we | |
1213 | * might have. | |
1214 | */ | |
8efc0c15 | 1215 | |
5260325f | 1216 | void |
1217 | channel_stop_listening() | |
8efc0c15 | 1218 | { |
5260325f | 1219 | int i; |
1220 | for (i = 0; i < channels_alloc; i++) { | |
1221 | switch (channels[i].type) { | |
1222 | case SSH_CHANNEL_AUTH_SOCKET: | |
1223 | close(channels[i].sock); | |
1224 | remove(channels[i].path); | |
1225 | channel_free(i); | |
1226 | break; | |
1227 | case SSH_CHANNEL_PORT_LISTENER: | |
1228 | case SSH_CHANNEL_X11_LISTENER: | |
1229 | close(channels[i].sock); | |
1230 | channel_free(i); | |
1231 | break; | |
1232 | default: | |
1233 | break; | |
1234 | } | |
8efc0c15 | 1235 | } |
8efc0c15 | 1236 | } |
1237 | ||
aa3378df | 1238 | /* |
1239 | * Closes the sockets of all channels. This is used to close extra file | |
1240 | * descriptors after a fork. | |
1241 | */ | |
8efc0c15 | 1242 | |
5260325f | 1243 | void |
1244 | channel_close_all() | |
8efc0c15 | 1245 | { |
5260325f | 1246 | int i; |
1247 | for (i = 0; i < channels_alloc; i++) { | |
1248 | if (channels[i].type != SSH_CHANNEL_FREE) | |
1249 | close(channels[i].sock); | |
1250 | } | |
8efc0c15 | 1251 | } |
1252 | ||
1253 | /* Returns the maximum file descriptor number used by the channels. */ | |
1254 | ||
5260325f | 1255 | int |
1256 | channel_max_fd() | |
8efc0c15 | 1257 | { |
5260325f | 1258 | return channel_max_fd_value; |
8efc0c15 | 1259 | } |
1260 | ||
1261 | /* Returns true if any channel is still open. */ | |
1262 | ||
5260325f | 1263 | int |
1264 | channel_still_open() | |
8efc0c15 | 1265 | { |
5260325f | 1266 | unsigned int i; |
1267 | for (i = 0; i < channels_alloc; i++) | |
1268 | switch (channels[i].type) { | |
1269 | case SSH_CHANNEL_FREE: | |
1270 | case SSH_CHANNEL_X11_LISTENER: | |
1271 | case SSH_CHANNEL_PORT_LISTENER: | |
1272 | case SSH_CHANNEL_CLOSED: | |
1273 | case SSH_CHANNEL_AUTH_SOCKET: | |
1274 | continue; | |
7e7327a1 | 1275 | case SSH_CHANNEL_LARVAL: |
1276 | if (!compat20) | |
1277 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); | |
1278 | continue; | |
5260325f | 1279 | case SSH_CHANNEL_OPENING: |
1280 | case SSH_CHANNEL_OPEN: | |
1281 | case SSH_CHANNEL_X11_OPEN: | |
1282 | return 1; | |
1283 | case SSH_CHANNEL_INPUT_DRAINING: | |
1284 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
1285 | if (!compat13) | |
1286 | fatal("cannot happen: OUT_DRAIN"); | |
1287 | return 1; | |
1288 | default: | |
1289 | fatal("channel_still_open: bad channel type %d", channels[i].type); | |
1290 | /* NOTREACHED */ | |
1291 | } | |
1292 | return 0; | |
8efc0c15 | 1293 | } |
1294 | ||
aa3378df | 1295 | /* |
1296 | * Returns a message describing the currently open forwarded connections, | |
1297 | * suitable for sending to the client. The message contains crlf pairs for | |
1298 | * newlines. | |
1299 | */ | |
8efc0c15 | 1300 | |
5260325f | 1301 | char * |
1302 | channel_open_message() | |
8efc0c15 | 1303 | { |
5260325f | 1304 | Buffer buffer; |
1305 | int i; | |
1306 | char buf[512], *cp; | |
1307 | ||
1308 | buffer_init(&buffer); | |
1309 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); | |
8efc0c15 | 1310 | buffer_append(&buffer, buf, strlen(buf)); |
5260325f | 1311 | for (i = 0; i < channels_alloc; i++) { |
1312 | Channel *c = &channels[i]; | |
1313 | switch (c->type) { | |
1314 | case SSH_CHANNEL_FREE: | |
1315 | case SSH_CHANNEL_X11_LISTENER: | |
1316 | case SSH_CHANNEL_PORT_LISTENER: | |
1317 | case SSH_CHANNEL_CLOSED: | |
1318 | case SSH_CHANNEL_AUTH_SOCKET: | |
1319 | continue; | |
7e7327a1 | 1320 | case SSH_CHANNEL_LARVAL: |
5260325f | 1321 | case SSH_CHANNEL_OPENING: |
1322 | case SSH_CHANNEL_OPEN: | |
1323 | case SSH_CHANNEL_X11_OPEN: | |
1324 | case SSH_CHANNEL_INPUT_DRAINING: | |
1325 | case SSH_CHANNEL_OUTPUT_DRAINING: | |
7368a6c8 | 1326 | snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n", |
48e671d5 | 1327 | c->self, c->remote_name, |
1328 | c->type, c->remote_id, | |
1329 | c->istate, buffer_len(&c->input), | |
7368a6c8 | 1330 | c->ostate, buffer_len(&c->output), |
1331 | c->rfd, c->wfd); | |
5260325f | 1332 | buffer_append(&buffer, buf, strlen(buf)); |
1333 | continue; | |
1334 | default: | |
7368a6c8 | 1335 | fatal("channel_open_message: bad channel type %d", c->type); |
5260325f | 1336 | /* NOTREACHED */ |
1337 | } | |
1338 | } | |
1339 | buffer_append(&buffer, "\0", 1); | |
1340 | cp = xstrdup(buffer_ptr(&buffer)); | |
1341 | buffer_free(&buffer); | |
1342 | return cp; | |
8efc0c15 | 1343 | } |
1344 | ||
aa3378df | 1345 | /* |
1346 | * Initiate forwarding of connections to local port "port" through the secure | |
1347 | * channel to host:port from remote side. | |
1348 | */ | |
8efc0c15 | 1349 | |
5260325f | 1350 | void |
57112b5a | 1351 | channel_request_local_forwarding(u_short port, const char *host, |
95f1eccc | 1352 | u_short host_port, int gateway_ports) |
8efc0c15 | 1353 | { |
48e671d5 | 1354 | int success, ch, sock, on = 1; |
1355 | struct addrinfo hints, *ai, *aitop; | |
1356 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
aa3378df | 1357 | struct linger linger; |
5260325f | 1358 | |
1359 | if (strlen(host) > sizeof(channels[0].path) - 1) | |
1360 | packet_disconnect("Forward host name too long."); | |
1361 | ||
aa3378df | 1362 | /* |
48e671d5 | 1363 | * getaddrinfo returns a loopback address if the hostname is |
1364 | * set to NULL and hints.ai_flags is not AI_PASSIVE | |
aa3378df | 1365 | */ |
48e671d5 | 1366 | memset(&hints, 0, sizeof(hints)); |
1367 | hints.ai_family = IPv4or6; | |
1368 | hints.ai_flags = gateway_ports ? AI_PASSIVE : 0; | |
1369 | hints.ai_socktype = SOCK_STREAM; | |
1370 | snprintf(strport, sizeof strport, "%d", port); | |
1371 | if (getaddrinfo(NULL, strport, &hints, &aitop) != 0) | |
1372 | packet_disconnect("getaddrinfo: fatal error"); | |
1373 | ||
1374 | success = 0; | |
1375 | for (ai = aitop; ai; ai = ai->ai_next) { | |
1376 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1377 | continue; | |
1378 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
1379 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
1380 | error("channel_request_local_forwarding: getnameinfo failed"); | |
1381 | continue; | |
1382 | } | |
1383 | /* Create a port to listen for the host. */ | |
1384 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1385 | if (sock < 0) { | |
1386 | /* this is no error since kernel may not support ipv6 */ | |
1387 | verbose("socket: %.100s", strerror(errno)); | |
1388 | continue; | |
1389 | } | |
1390 | /* | |
1391 | * Set socket options. We would like the socket to disappear | |
1392 | * as soon as it has been closed for whatever reason. | |
1393 | */ | |
1394 | setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); | |
1395 | linger.l_onoff = 1; | |
1396 | linger.l_linger = 5; | |
1397 | setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger)); | |
1398 | debug("Local forwarding listening on %s port %s.", ntop, strport); | |
1399 | ||
1400 | /* Bind the socket to the address. */ | |
1401 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1402 | /* address can be in use ipv6 address is already bound */ | |
16218745 | 1403 | if (!ai->ai_next) |
1404 | error("bind: %.100s", strerror(errno)); | |
1405 | else | |
1406 | verbose("bind: %.100s", strerror(errno)); | |
1407 | ||
48e671d5 | 1408 | close(sock); |
1409 | continue; | |
1410 | } | |
1411 | /* Start listening for connections on the socket. */ | |
1412 | if (listen(sock, 5) < 0) { | |
1413 | error("listen: %.100s", strerror(errno)); | |
1414 | close(sock); | |
1415 | continue; | |
1416 | } | |
1417 | /* Allocate a channel number for the socket. */ | |
7368a6c8 | 1418 | ch = channel_new( |
1419 | "port listener", SSH_CHANNEL_PORT_LISTENER, | |
1420 | sock, sock, -1, | |
1421 | CHAN_WINDOW_DEFAULT, CHAN_PACKET_DEFAULT, | |
1422 | 0, xstrdup("port listener")); | |
48e671d5 | 1423 | strlcpy(channels[ch].path, host, sizeof(channels[ch].path)); |
1424 | channels[ch].host_port = host_port; | |
1425 | channels[ch].listening_port = port; | |
1426 | success = 1; | |
1427 | } | |
1428 | if (success == 0) | |
1429 | packet_disconnect("cannot listen port: %d", port); | |
1430 | freeaddrinfo(aitop); | |
5260325f | 1431 | } |
8efc0c15 | 1432 | |
aa3378df | 1433 | /* |
1434 | * Initiate forwarding of connections to port "port" on remote host through | |
1435 | * the secure channel to host:port from local side. | |
1436 | */ | |
8efc0c15 | 1437 | |
5260325f | 1438 | void |
7368a6c8 | 1439 | channel_request_remote_forwarding(u_short listen_port, const char *host_to_connect, |
1440 | u_short port_to_connect) | |
8efc0c15 | 1441 | { |
5260325f | 1442 | int payload_len; |
1443 | /* Record locally that connection to this host/port is permitted. */ | |
1444 | if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION) | |
1445 | fatal("channel_request_remote_forwarding: too many forwards"); | |
1446 | ||
7368a6c8 | 1447 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect); |
1448 | permitted_opens[num_permitted_opens].port_to_connect = port_to_connect; | |
1449 | permitted_opens[num_permitted_opens].listen_port = listen_port; | |
5260325f | 1450 | num_permitted_opens++; |
1451 | ||
1452 | /* Send the forward request to the remote side. */ | |
7e7327a1 | 1453 | if (compat20) { |
1454 | const char *address_to_bind = "0.0.0.0"; | |
1455 | packet_start(SSH2_MSG_GLOBAL_REQUEST); | |
1456 | packet_put_cstring("tcpip-forward"); | |
1457 | packet_put_char(0); /* boolean: want reply */ | |
1458 | packet_put_cstring(address_to_bind); | |
1459 | packet_put_int(listen_port); | |
1460 | } else { | |
1461 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); | |
1462 | packet_put_int(port_to_connect); | |
1463 | packet_put_cstring(host_to_connect); | |
1464 | packet_put_int(listen_port); | |
1465 | packet_send(); | |
1466 | packet_write_wait(); | |
1467 | /* | |
1468 | * Wait for response from the remote side. It will send a disconnect | |
1469 | * message on failure, and we will never see it here. | |
1470 | */ | |
1471 | packet_read_expect(&payload_len, SSH_SMSG_SUCCESS); | |
1472 | } | |
8efc0c15 | 1473 | } |
1474 | ||
aa3378df | 1475 | /* |
1476 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates | |
1477 | * listening for the port, and sends back a success reply (or disconnect | |
1478 | * message if there was an error). This never returns if there was an error. | |
1479 | */ | |
8efc0c15 | 1480 | |
5260325f | 1481 | void |
1482 | channel_input_port_forward_request(int is_root) | |
8efc0c15 | 1483 | { |
57112b5a | 1484 | u_short port, host_port; |
5260325f | 1485 | char *hostname; |
1486 | ||
1487 | /* Get arguments from the packet. */ | |
1488 | port = packet_get_int(); | |
1489 | hostname = packet_get_string(NULL); | |
1490 | host_port = packet_get_int(); | |
1491 | ||
aa3378df | 1492 | /* |
1493 | * Check that an unprivileged user is not trying to forward a | |
1494 | * privileged port. | |
1495 | */ | |
5260325f | 1496 | if (port < IPPORT_RESERVED && !is_root) |
1497 | packet_disconnect("Requested forwarding of port %d but user is not root.", | |
1498 | port); | |
95f1eccc | 1499 | /* |
1500 | * Initiate forwarding, | |
1501 | * bind port to localhost only (gateway ports == 0). | |
1502 | */ | |
1503 | channel_request_local_forwarding(port, hostname, host_port, 0); | |
5260325f | 1504 | |
1505 | /* Free the argument string. */ | |
1506 | xfree(hostname); | |
8efc0c15 | 1507 | } |
1508 | ||
7368a6c8 | 1509 | /* XXX move to aux.c */ |
1510 | int | |
1511 | channel_connect_to(const char *host, u_short host_port) | |
8efc0c15 | 1512 | { |
48e671d5 | 1513 | struct addrinfo hints, *ai, *aitop; |
1514 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
1515 | int gaierr; | |
7368a6c8 | 1516 | int sock = -1; |
48e671d5 | 1517 | |
1518 | memset(&hints, 0, sizeof(hints)); | |
1519 | hints.ai_family = IPv4or6; | |
1520 | hints.ai_socktype = SOCK_STREAM; | |
1521 | snprintf(strport, sizeof strport, "%d", host_port); | |
1522 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) { | |
1523 | error("%.100s: unknown host (%s)", host, gai_strerror(gaierr)); | |
7368a6c8 | 1524 | return -1; |
48e671d5 | 1525 | } |
48e671d5 | 1526 | for (ai = aitop; ai; ai = ai->ai_next) { |
1527 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1528 | continue; | |
1529 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), | |
1530 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
7368a6c8 | 1531 | error("channel_connect_to: getnameinfo failed"); |
48e671d5 | 1532 | continue; |
5260325f | 1533 | } |
48e671d5 | 1534 | /* Create the socket. */ |
1535 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1536 | if (sock < 0) { | |
1537 | error("socket: %.100s", strerror(errno)); | |
1538 | continue; | |
5260325f | 1539 | } |
48e671d5 | 1540 | /* Connect to the host/port. */ |
1541 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1542 | error("connect %.100s port %s: %.100s", ntop, strport, | |
1543 | strerror(errno)); | |
1544 | close(sock); | |
1545 | continue; /* fail -- try next */ | |
1546 | } | |
1547 | break; /* success */ | |
5260325f | 1548 | |
5260325f | 1549 | } |
48e671d5 | 1550 | freeaddrinfo(aitop); |
48e671d5 | 1551 | if (!ai) { |
1552 | error("connect %.100s port %d: failed.", host, host_port); | |
7368a6c8 | 1553 | return -1; |
8efc0c15 | 1554 | } |
7368a6c8 | 1555 | /* success */ |
1556 | return sock; | |
1557 | } | |
48e671d5 | 1558 | |
7368a6c8 | 1559 | /* |
1560 | * This is called after receiving PORT_OPEN message. This attempts to | |
1561 | * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION | |
1562 | * or CHANNEL_OPEN_FAILURE. | |
1563 | */ | |
5260325f | 1564 | |
7368a6c8 | 1565 | void |
1566 | channel_input_port_open(int type, int plen) | |
1567 | { | |
1568 | u_short host_port; | |
1569 | char *host, *originator_string; | |
1570 | int remote_channel, sock = -1, newch, i, denied; | |
1571 | unsigned int host_len, originator_len; | |
5260325f | 1572 | |
7368a6c8 | 1573 | /* Get remote channel number. */ |
1574 | remote_channel = packet_get_int(); | |
5260325f | 1575 | |
7368a6c8 | 1576 | /* Get host name to connect to. */ |
1577 | host = packet_get_string(&host_len); | |
5260325f | 1578 | |
7368a6c8 | 1579 | /* Get port to connect to. */ |
1580 | host_port = packet_get_int(); | |
5260325f | 1581 | |
7368a6c8 | 1582 | /* Get remote originator name. */ |
1583 | if (have_hostname_in_open) { | |
1584 | originator_string = packet_get_string(&originator_len); | |
1585 | originator_len += 4; /* size of packet_int */ | |
1586 | } else { | |
1587 | originator_string = xstrdup("unknown (remote did not supply name)"); | |
1588 | originator_len = 0; /* no originator supplied */ | |
1589 | } | |
5260325f | 1590 | |
7368a6c8 | 1591 | packet_integrity_check(plen, |
1592 | 4 + 4 + host_len + 4 + originator_len, SSH_MSG_PORT_OPEN); | |
1593 | ||
1594 | /* Check if opening that port is permitted. */ | |
1595 | denied = 0; | |
1596 | if (!all_opens_permitted) { | |
1597 | /* Go trough all permitted ports. */ | |
1598 | for (i = 0; i < num_permitted_opens; i++) | |
1599 | if (permitted_opens[i].port_to_connect == host_port && | |
1600 | strcmp(permitted_opens[i].host_to_connect, host) == 0) | |
1601 | break; | |
1602 | ||
1603 | /* Check if we found the requested port among those permitted. */ | |
1604 | if (i >= num_permitted_opens) { | |
1605 | /* The port is not permitted. */ | |
1606 | log("Received request to connect to %.100s:%d, but the request was denied.", | |
1607 | host, host_port); | |
1608 | denied = 1; | |
1609 | } | |
1610 | } | |
1611 | sock = denied ? -1 : channel_connect_to(host, host_port); | |
1612 | if (sock > 0) { | |
1613 | /* Allocate a channel for this connection. */ | |
1614 | newch = channel_allocate(SSH_CHANNEL_OPEN, sock, originator_string); | |
1615 | channels[newch].remote_id = remote_channel; | |
1616 | ||
1617 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1618 | packet_put_int(remote_channel); | |
1619 | packet_put_int(newch); | |
1620 | packet_send(); | |
1621 | } else { | |
1622 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1623 | packet_put_int(remote_channel); | |
1624 | packet_send(); | |
1625 | } | |
1626 | xfree(host); | |
8efc0c15 | 1627 | } |
1628 | ||
aa3378df | 1629 | /* |
1630 | * Creates an internet domain socket for listening for X11 connections. | |
1631 | * Returns a suitable value for the DISPLAY variable, or NULL if an error | |
1632 | * occurs. | |
1633 | */ | |
8efc0c15 | 1634 | |
48e671d5 | 1635 | #define NUM_SOCKS 10 |
1636 | ||
5260325f | 1637 | char * |
95f1eccc | 1638 | x11_create_display_inet(int screen_number, int x11_display_offset) |
8efc0c15 | 1639 | { |
57112b5a | 1640 | int display_number, sock; |
1641 | u_short port; | |
48e671d5 | 1642 | struct addrinfo hints, *ai, *aitop; |
1643 | char strport[NI_MAXSERV]; | |
1644 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; | |
1645 | char display[512]; | |
5260325f | 1646 | char hostname[MAXHOSTNAMELEN]; |
1647 | ||
95f1eccc | 1648 | for (display_number = x11_display_offset; |
5260325f | 1649 | display_number < MAX_DISPLAYS; |
1650 | display_number++) { | |
1651 | port = 6000 + display_number; | |
48e671d5 | 1652 | memset(&hints, 0, sizeof(hints)); |
1653 | hints.ai_family = IPv4or6; | |
1654 | hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */ | |
1655 | hints.ai_socktype = SOCK_STREAM; | |
1656 | snprintf(strport, sizeof strport, "%d", port); | |
1657 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { | |
1658 | error("getaddrinfo: %.100s", gai_strerror(gaierr)); | |
5260325f | 1659 | return NULL; |
1660 | } | |
48e671d5 | 1661 | for (ai = aitop; ai; ai = ai->ai_next) { |
1662 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1663 | continue; | |
1664 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1665 | if (sock < 0) { | |
80a44451 | 1666 | if (errno != EINVAL) { |
1667 | error("socket: %.100s", strerror(errno)); | |
1668 | return NULL; | |
1669 | } else { | |
1670 | debug("Socket family %d not supported [X11 disp create]", ai->ai_family); | |
1671 | continue; | |
1672 | } | |
48e671d5 | 1673 | } |
1674 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1675 | debug("bind port %d: %.100s", port, strerror(errno)); | |
1676 | shutdown(sock, SHUT_RDWR); | |
1677 | close(sock); | |
16218745 | 1678 | |
1679 | if (ai->ai_next) | |
1680 | continue; | |
1681 | ||
48e671d5 | 1682 | for (n = 0; n < num_socks; n++) { |
1683 | shutdown(socks[n], SHUT_RDWR); | |
1684 | close(socks[n]); | |
1685 | } | |
1686 | num_socks = 0; | |
1687 | break; | |
1688 | } | |
1689 | socks[num_socks++] = sock; | |
80faa19f | 1690 | #ifndef DONT_TRY_OTHER_AF |
48e671d5 | 1691 | if (num_socks == NUM_SOCKS) |
1692 | break; | |
80faa19f | 1693 | #else |
1694 | break; | |
1695 | #endif | |
5260325f | 1696 | } |
48e671d5 | 1697 | if (num_socks > 0) |
1698 | break; | |
5260325f | 1699 | } |
1700 | if (display_number >= MAX_DISPLAYS) { | |
1701 | error("Failed to allocate internet-domain X11 display socket."); | |
1702 | return NULL; | |
8efc0c15 | 1703 | } |
5260325f | 1704 | /* Start listening for connections on the socket. */ |
48e671d5 | 1705 | for (n = 0; n < num_socks; n++) { |
1706 | sock = socks[n]; | |
1707 | if (listen(sock, 5) < 0) { | |
1708 | error("listen: %.100s", strerror(errno)); | |
1709 | shutdown(sock, SHUT_RDWR); | |
1710 | close(sock); | |
1711 | return NULL; | |
1712 | } | |
8efc0c15 | 1713 | } |
48e671d5 | 1714 | |
5260325f | 1715 | /* Set up a suitable value for the DISPLAY variable. */ |
a7effaac | 1716 | |
5260325f | 1717 | if (gethostname(hostname, sizeof(hostname)) < 0) |
1718 | fatal("gethostname: %.100s", strerror(errno)); | |
a7effaac | 1719 | |
1720 | #ifdef IPADDR_IN_DISPLAY | |
1721 | /* | |
1722 | * HPUX detects the local hostname in the DISPLAY variable and tries | |
1723 | * to set up a shared memory connection to the server, which it | |
1724 | * incorrectly supposes to be local. | |
1725 | * | |
1726 | * The workaround - as used in later $$H and other programs - is | |
1727 | * is to set display to the host's IP address. | |
1728 | */ | |
1729 | { | |
1730 | struct hostent *he; | |
1731 | struct in_addr my_addr; | |
1732 | ||
1733 | he = gethostbyname(hostname); | |
1734 | if (he == NULL) { | |
1735 | error("[X11-broken-fwd-hostname-workaround] Could not get " | |
1736 | "IP address for hostname %s.", hostname); | |
1737 | ||
1738 | packet_send_debug("[X11-broken-fwd-hostname-workaround]" | |
1739 | "Could not get IP address for hostname %s.", hostname); | |
1740 | ||
1741 | shutdown(sock, SHUT_RDWR); | |
1742 | close(sock); | |
1743 | ||
1744 | return NULL; | |
1745 | } | |
1746 | ||
1747 | memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr)); | |
1748 | ||
1749 | /* Set DISPLAY to <ip address>:screen.display */ | |
48e671d5 | 1750 | snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr), |
a7effaac | 1751 | display_number, screen_number); |
1752 | } | |
1753 | #else /* IPADDR_IN_DISPLAY */ | |
1754 | /* Just set DISPLAY to hostname:screen.display */ | |
48e671d5 | 1755 | snprintf(display, sizeof display, "%.400s:%d.%d", hostname, |
a7effaac | 1756 | display_number, screen_number); |
1757 | #endif /* IPADDR_IN_DISPLAY */ | |
5260325f | 1758 | |
48e671d5 | 1759 | /* Allocate a channel for each socket. */ |
1760 | for (n = 0; n < num_socks; n++) { | |
1761 | sock = socks[n]; | |
1762 | (void) channel_allocate(SSH_CHANNEL_X11_LISTENER, sock, | |
1763 | xstrdup("X11 inet listener")); | |
1764 | } | |
5260325f | 1765 | |
1766 | /* Return a suitable value for the DISPLAY environment variable. */ | |
48e671d5 | 1767 | return xstrdup(display); |
8efc0c15 | 1768 | } |
1769 | ||
1770 | #ifndef X_UNIX_PATH | |
1771 | #define X_UNIX_PATH "/tmp/.X11-unix/X" | |
1772 | #endif | |
1773 | ||
1774 | static | |
1775 | int | |
2f450969 | 1776 | connect_local_xsocket(unsigned int dnr) |
8efc0c15 | 1777 | { |
5260325f | 1778 | static const char *const x_sockets[] = { |
1779 | X_UNIX_PATH "%u", | |
1780 | "/var/X/.X11-unix/X" "%u", | |
1781 | "/usr/spool/sockets/X11/" "%u", | |
1782 | NULL | |
1783 | }; | |
1784 | int sock; | |
1785 | struct sockaddr_un addr; | |
1786 | const char *const * path; | |
1787 | ||
1788 | for (path = x_sockets; *path; ++path) { | |
1789 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
1790 | if (sock < 0) | |
1791 | error("socket: %.100s", strerror(errno)); | |
1792 | memset(&addr, 0, sizeof(addr)); | |
1793 | addr.sun_family = AF_UNIX; | |
1794 | snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr); | |
1795 | if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0) | |
1796 | return sock; | |
1797 | close(sock); | |
1798 | } | |
1799 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); | |
1800 | return -1; | |
8efc0c15 | 1801 | } |
1802 | ||
1803 | ||
aa3378df | 1804 | /* |
1805 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains | |
1806 | * the remote channel number. We should do whatever we want, and respond | |
1807 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. | |
1808 | */ | |
8efc0c15 | 1809 | |
5260325f | 1810 | void |
7368a6c8 | 1811 | x11_input_open(int type, int plen) |
8efc0c15 | 1812 | { |
48e671d5 | 1813 | int remote_channel, display_number, sock = 0, newch; |
5260325f | 1814 | const char *display; |
5260325f | 1815 | char buf[1024], *cp, *remote_host; |
610cd5c6 | 1816 | unsigned int remote_len; |
48e671d5 | 1817 | struct addrinfo hints, *ai, *aitop; |
1818 | char strport[NI_MAXSERV]; | |
1819 | int gaierr; | |
5260325f | 1820 | |
1821 | /* Get remote channel number. */ | |
1822 | remote_channel = packet_get_int(); | |
1823 | ||
1824 | /* Get remote originator name. */ | |
aa3378df | 1825 | if (have_hostname_in_open) { |
5260325f | 1826 | remote_host = packet_get_string(&remote_len); |
aa3378df | 1827 | remote_len += 4; |
1828 | } else { | |
5260325f | 1829 | remote_host = xstrdup("unknown (remote did not supply name)"); |
aa3378df | 1830 | remote_len = 0; |
1831 | } | |
5260325f | 1832 | |
1833 | debug("Received X11 open request."); | |
7368a6c8 | 1834 | packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN); |
5260325f | 1835 | |
1836 | /* Try to open a socket for the local X server. */ | |
1837 | display = getenv("DISPLAY"); | |
1838 | if (!display) { | |
1839 | error("DISPLAY not set."); | |
1840 | goto fail; | |
1841 | } | |
aa3378df | 1842 | /* |
1843 | * Now we decode the value of the DISPLAY variable and make a | |
1844 | * connection to the real X server. | |
1845 | */ | |
1846 | ||
1847 | /* | |
1848 | * Check if it is a unix domain socket. Unix domain displays are in | |
1849 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] | |
1850 | */ | |
5260325f | 1851 | if (strncmp(display, "unix:", 5) == 0 || |
1852 | display[0] == ':') { | |
1853 | /* Connect to the unix domain socket. */ | |
1854 | if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) { | |
1855 | error("Could not parse display number from DISPLAY: %.100s", | |
1856 | display); | |
1857 | goto fail; | |
1858 | } | |
1859 | /* Create a socket. */ | |
1860 | sock = connect_local_xsocket(display_number); | |
1861 | if (sock < 0) | |
1862 | goto fail; | |
1863 | ||
1864 | /* OK, we now have a connection to the display. */ | |
1865 | goto success; | |
1866 | } | |
aa3378df | 1867 | /* |
1868 | * Connect to an inet socket. The DISPLAY value is supposedly | |
1869 | * hostname:d[.s], where hostname may also be numeric IP address. | |
1870 | */ | |
5260325f | 1871 | strncpy(buf, display, sizeof(buf)); |
1872 | buf[sizeof(buf) - 1] = 0; | |
1873 | cp = strchr(buf, ':'); | |
1874 | if (!cp) { | |
1875 | error("Could not find ':' in DISPLAY: %.100s", display); | |
1876 | goto fail; | |
1877 | } | |
1878 | *cp = 0; | |
aa3378df | 1879 | /* buf now contains the host name. But first we parse the display number. */ |
5260325f | 1880 | if (sscanf(cp + 1, "%d", &display_number) != 1) { |
1881 | error("Could not parse display number from DISPLAY: %.100s", | |
1882 | display); | |
1883 | goto fail; | |
1884 | } | |
5260325f | 1885 | |
48e671d5 | 1886 | /* Look up the host address */ |
1887 | memset(&hints, 0, sizeof(hints)); | |
1888 | hints.ai_family = IPv4or6; | |
1889 | hints.ai_socktype = SOCK_STREAM; | |
1890 | snprintf(strport, sizeof strport, "%d", 6000 + display_number); | |
1891 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { | |
1892 | error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr)); | |
5260325f | 1893 | goto fail; |
8efc0c15 | 1894 | } |
48e671d5 | 1895 | for (ai = aitop; ai; ai = ai->ai_next) { |
1896 | /* Create a socket. */ | |
1897 | sock = socket(ai->ai_family, SOCK_STREAM, 0); | |
1898 | if (sock < 0) { | |
1899 | debug("socket: %.100s", strerror(errno)); | |
7368a6c8 | 1900 | continue; |
1901 | } | |
1902 | /* Connect it to the display. */ | |
1903 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1904 | debug("connect %.100s port %d: %.100s", buf, | |
1905 | 6000 + display_number, strerror(errno)); | |
1906 | close(sock); | |
1907 | continue; | |
1908 | } | |
1909 | /* Success */ | |
1910 | break; | |
48e671d5 | 1911 | } |
48e671d5 | 1912 | freeaddrinfo(aitop); |
1913 | if (!ai) { | |
1914 | error("connect %.100s port %d: %.100s", buf, 6000 + display_number, | |
1915 | strerror(errno)); | |
5260325f | 1916 | goto fail; |
8efc0c15 | 1917 | } |
5260325f | 1918 | success: |
1919 | /* We have successfully obtained a connection to the real X display. */ | |
1920 | ||
1921 | /* Allocate a channel for this connection. */ | |
1922 | if (x11_saved_proto == NULL) | |
1923 | newch = channel_allocate(SSH_CHANNEL_OPEN, sock, remote_host); | |
1924 | else | |
1925 | newch = channel_allocate(SSH_CHANNEL_X11_OPEN, sock, remote_host); | |
1926 | channels[newch].remote_id = remote_channel; | |
1927 | ||
1928 | /* Send a confirmation to the remote host. */ | |
1929 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
1930 | packet_put_int(remote_channel); | |
1931 | packet_put_int(newch); | |
1932 | packet_send(); | |
1933 | ||
1934 | return; | |
1935 | ||
1936 | fail: | |
1937 | /* Send refusal to the remote host. */ | |
1938 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
1939 | packet_put_int(remote_channel); | |
1940 | packet_send(); | |
8efc0c15 | 1941 | } |
1942 | ||
aa3378df | 1943 | /* |
1944 | * Requests forwarding of X11 connections, generates fake authentication | |
1945 | * data, and enables authentication spoofing. | |
1946 | */ | |
8efc0c15 | 1947 | |
5260325f | 1948 | void |
1949 | x11_request_forwarding_with_spoofing(const char *proto, const char *data) | |
8efc0c15 | 1950 | { |
5260325f | 1951 | unsigned int data_len = (unsigned int) strlen(data) / 2; |
1952 | unsigned int i, value; | |
1953 | char *new_data; | |
1954 | int screen_number; | |
1955 | const char *cp; | |
1956 | u_int32_t rand = 0; | |
1957 | ||
1958 | cp = getenv("DISPLAY"); | |
1959 | if (cp) | |
1960 | cp = strchr(cp, ':'); | |
1961 | if (cp) | |
1962 | cp = strchr(cp, '.'); | |
1963 | if (cp) | |
1964 | screen_number = atoi(cp + 1); | |
1965 | else | |
1966 | screen_number = 0; | |
1967 | ||
1968 | /* Save protocol name. */ | |
1969 | x11_saved_proto = xstrdup(proto); | |
1970 | ||
aa3378df | 1971 | /* |
1972 | * Extract real authentication data and generate fake data of the | |
1973 | * same length. | |
1974 | */ | |
5260325f | 1975 | x11_saved_data = xmalloc(data_len); |
1976 | x11_fake_data = xmalloc(data_len); | |
1977 | for (i = 0; i < data_len; i++) { | |
1978 | if (sscanf(data + 2 * i, "%2x", &value) != 1) | |
1979 | fatal("x11_request_forwarding: bad authentication data: %.100s", data); | |
1980 | if (i % 4 == 0) | |
1981 | rand = arc4random(); | |
1982 | x11_saved_data[i] = value; | |
1983 | x11_fake_data[i] = rand & 0xff; | |
1984 | rand >>= 8; | |
1985 | } | |
1986 | x11_saved_data_len = data_len; | |
1987 | x11_fake_data_len = data_len; | |
1988 | ||
1989 | /* Convert the fake data into hex. */ | |
1990 | new_data = xmalloc(2 * data_len + 1); | |
1991 | for (i = 0; i < data_len; i++) | |
1992 | sprintf(new_data + 2 * i, "%02x", (unsigned char) x11_fake_data[i]); | |
1993 | ||
1994 | /* Send the request packet. */ | |
1995 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); | |
1996 | packet_put_string(proto, strlen(proto)); | |
1997 | packet_put_string(new_data, strlen(new_data)); | |
1998 | packet_put_int(screen_number); | |
1999 | packet_send(); | |
2000 | packet_write_wait(); | |
2001 | xfree(new_data); | |
8efc0c15 | 2002 | } |
2003 | ||
2004 | /* Sends a message to the server to request authentication fd forwarding. */ | |
2005 | ||
5260325f | 2006 | void |
2007 | auth_request_forwarding() | |
8efc0c15 | 2008 | { |
5260325f | 2009 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
2010 | packet_send(); | |
2011 | packet_write_wait(); | |
8efc0c15 | 2012 | } |
2013 | ||
aa3378df | 2014 | /* |
2015 | * Returns the name of the forwarded authentication socket. Returns NULL if | |
2016 | * there is no forwarded authentication socket. The returned value points to | |
2017 | * a static buffer. | |
2018 | */ | |
8efc0c15 | 2019 | |
5260325f | 2020 | char * |
2021 | auth_get_socket_name() | |
8efc0c15 | 2022 | { |
5260325f | 2023 | return channel_forwarded_auth_socket_name; |
8efc0c15 | 2024 | } |
2025 | ||
2026 | /* removes the agent forwarding socket */ | |
2027 | ||
5260325f | 2028 | void |
2029 | cleanup_socket(void) | |
2030 | { | |
2031 | remove(channel_forwarded_auth_socket_name); | |
2032 | rmdir(channel_forwarded_auth_socket_dir); | |
8efc0c15 | 2033 | } |
2034 | ||
aa3378df | 2035 | /* |
2036 | * This if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. | |
2037 | * This starts forwarding authentication requests. | |
2038 | */ | |
8efc0c15 | 2039 | |
5260325f | 2040 | void |
2041 | auth_input_request_forwarding(struct passwd * pw) | |
8efc0c15 | 2042 | { |
5260325f | 2043 | int sock, newch; |
2044 | struct sockaddr_un sunaddr; | |
2045 | ||
2046 | if (auth_get_socket_name() != NULL) | |
2047 | fatal("Protocol error: authentication forwarding requested twice."); | |
2048 | ||
2049 | /* Temporarily drop privileged uid for mkdir/bind. */ | |
2050 | temporarily_use_uid(pw->pw_uid); | |
2051 | ||
2052 | /* Allocate a buffer for the socket name, and format the name. */ | |
2053 | channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME); | |
2054 | channel_forwarded_auth_socket_dir = xmalloc(MAX_SOCKET_NAME); | |
2055 | strlcpy(channel_forwarded_auth_socket_dir, "/tmp/ssh-XXXXXXXX", MAX_SOCKET_NAME); | |
2056 | ||
2057 | /* Create private directory for socket */ | |
2058 | if (mkdtemp(channel_forwarded_auth_socket_dir) == NULL) | |
2059 | packet_disconnect("mkdtemp: %.100s", strerror(errno)); | |
2060 | snprintf(channel_forwarded_auth_socket_name, MAX_SOCKET_NAME, "%s/agent.%d", | |
2061 | channel_forwarded_auth_socket_dir, (int) getpid()); | |
2062 | ||
2063 | if (atexit(cleanup_socket) < 0) { | |
2064 | int saved = errno; | |
2065 | cleanup_socket(); | |
2066 | packet_disconnect("socket: %.100s", strerror(saved)); | |
2067 | } | |
2068 | /* Create the socket. */ | |
2069 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
2070 | if (sock < 0) | |
2071 | packet_disconnect("socket: %.100s", strerror(errno)); | |
2072 | ||
2073 | /* Bind it to the name. */ | |
2074 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
2075 | sunaddr.sun_family = AF_UNIX; | |
2076 | strncpy(sunaddr.sun_path, channel_forwarded_auth_socket_name, | |
2077 | sizeof(sunaddr.sun_path)); | |
2078 | ||
2079 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) | |
2080 | packet_disconnect("bind: %.100s", strerror(errno)); | |
2081 | ||
2082 | /* Restore the privileged uid. */ | |
2083 | restore_uid(); | |
2084 | ||
2085 | /* Start listening on the socket. */ | |
2086 | if (listen(sock, 5) < 0) | |
2087 | packet_disconnect("listen: %.100s", strerror(errno)); | |
2088 | ||
2089 | /* Allocate a channel for the authentication agent socket. */ | |
2090 | newch = channel_allocate(SSH_CHANNEL_AUTH_SOCKET, sock, | |
2091 | xstrdup("auth socket")); | |
a408af76 | 2092 | strlcpy(channels[newch].path, channel_forwarded_auth_socket_name, |
2093 | sizeof(channels[newch].path)); | |
8efc0c15 | 2094 | } |
2095 | ||
2096 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ | |
2097 | ||
5260325f | 2098 | void |
7368a6c8 | 2099 | auth_input_open_request(int type, int plen) |
8efc0c15 | 2100 | { |
5260325f | 2101 | int remch, sock, newch; |
2102 | char *dummyname; | |
2103 | ||
7368a6c8 | 2104 | packet_integrity_check(plen, 4, type); |
2105 | ||
5260325f | 2106 | /* Read the remote channel number from the message. */ |
2107 | remch = packet_get_int(); | |
2108 | ||
aa3378df | 2109 | /* |
2110 | * Get a connection to the local authentication agent (this may again | |
2111 | * get forwarded). | |
2112 | */ | |
5260325f | 2113 | sock = ssh_get_authentication_socket(); |
2114 | ||
aa3378df | 2115 | /* |
2116 | * If we could not connect the agent, send an error message back to | |
2117 | * the server. This should never happen unless the agent dies, | |
2118 | * because authentication forwarding is only enabled if we have an | |
2119 | * agent. | |
2120 | */ | |
5260325f | 2121 | if (sock < 0) { |
2122 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); | |
2123 | packet_put_int(remch); | |
2124 | packet_send(); | |
2125 | return; | |
2126 | } | |
2127 | debug("Forwarding authentication connection."); | |
2128 | ||
aa3378df | 2129 | /* |
2130 | * Dummy host name. This will be freed when the channel is freed; it | |
2131 | * will still be valid in the packet_put_string below since the | |
2132 | * channel cannot yet be freed at that point. | |
2133 | */ | |
5260325f | 2134 | dummyname = xstrdup("authentication agent connection"); |
2135 | ||
2136 | newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname); | |
2137 | channels[newch].remote_id = remch; | |
2138 | ||
2139 | /* Send a confirmation to the remote host. */ | |
2140 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); | |
2141 | packet_put_int(remch); | |
2142 | packet_put_int(newch); | |
2143 | packet_send(); | |
8efc0c15 | 2144 | } |
7e7327a1 | 2145 | |
2146 | void | |
2147 | channel_open(int id) | |
2148 | { | |
2149 | Channel *c = channel_lookup(id); | |
2150 | if (c == NULL) { | |
2151 | log("channel_open: %d: bad id", id); | |
2152 | return; | |
2153 | } | |
2154 | packet_start(SSH2_MSG_CHANNEL_OPEN); | |
2155 | packet_put_cstring(c->ctype); | |
2156 | packet_put_int(c->self); | |
2157 | packet_put_int(c->local_window); | |
2158 | packet_put_int(c->local_maxpacket); | |
2159 | packet_send(); | |
2160 | debug("channel open %d", id); | |
2161 | } | |
2162 | void | |
2163 | channel_request(int id, char *service, int wantconfirm) | |
2164 | { | |
2165 | channel_request_start(id, service, wantconfirm); | |
2166 | packet_send(); | |
2167 | debug("channel request %d: %s", id, service) ; | |
2168 | } | |
2169 | void | |
2170 | channel_request_start(int id, char *service, int wantconfirm) | |
2171 | { | |
2172 | Channel *c = channel_lookup(id); | |
2173 | if (c == NULL) { | |
2174 | log("channel_request: %d: bad id", id); | |
2175 | return; | |
2176 | } | |
2177 | packet_start(SSH2_MSG_CHANNEL_REQUEST); | |
2178 | packet_put_int(c->remote_id); | |
2179 | packet_put_cstring(service); | |
2180 | packet_put_char(wantconfirm); | |
2181 | } | |
2182 | void | |
2183 | channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg) | |
2184 | { | |
2185 | Channel *c = channel_lookup(id); | |
2186 | if (c == NULL) { | |
2187 | log("channel_register_callback: %d: bad id", id); | |
2188 | return; | |
2189 | } | |
2190 | c->cb_event = mtype; | |
2191 | c->cb_fn = fn; | |
2192 | c->cb_arg = arg; | |
2193 | } | |
2194 | void | |
2195 | channel_register_cleanup(int id, channel_callback_fn *fn) | |
2196 | { | |
2197 | Channel *c = channel_lookup(id); | |
2198 | if (c == NULL) { | |
2199 | log("channel_register_cleanup: %d: bad id", id); | |
2200 | return; | |
2201 | } | |
2202 | c->dettach_user = fn; | |
2203 | } | |
2204 | void | |
2205 | channel_cancel_cleanup(int id) | |
2206 | { | |
2207 | Channel *c = channel_lookup(id); | |
2208 | if (c == NULL) { | |
2209 | log("channel_cancel_cleanup: %d: bad id", id); | |
2210 | return; | |
2211 | } | |
2212 | c->dettach_user = NULL; | |
2213 | } | |
2214 | ||
2215 | void | |
2216 | channel_set_fds(int id, int rfd, int wfd, int efd, int extusage) | |
2217 | { | |
2218 | Channel *c = channel_lookup(id); | |
2219 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) | |
2220 | fatal("channel_activate for non-larval channel %d.", id); | |
2221 | if (rfd > channel_max_fd_value) | |
2222 | channel_max_fd_value = rfd; | |
2223 | if (wfd > channel_max_fd_value) | |
2224 | channel_max_fd_value = wfd; | |
2225 | if (efd > channel_max_fd_value) | |
2226 | channel_max_fd_value = efd; | |
2227 | c->type = SSH_CHANNEL_OPEN; | |
2228 | c->rfd = rfd; | |
2229 | c->wfd = wfd; | |
2230 | c->efd = efd; | |
2231 | c->extended_usage = extusage; | |
2232 | /* XXX window size? */ | |
2233 | c->local_window = c->local_window_max = c->local_maxpacket/2; | |
2234 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); | |
2235 | packet_put_int(c->remote_id); | |
2236 | packet_put_int(c->local_window); | |
2237 | packet_send(); | |
2238 | } |