Annotation of src/usr.bin/ssh/channels.c, Revision 1.365
1.365 ! deraadt 1: /* $OpenBSD: channels.c,v 1.364 2017/05/31 00:43:04 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.255 stevesk 55: #include <netdb.h>
1.341 millert 56: #include <stdint.h>
1.263 stevesk 57: #include <stdio.h>
1.262 stevesk 58: #include <stdlib.h>
1.260 stevesk 59: #include <string.h>
1.233 stevesk 60: #include <termios.h>
1.256 stevesk 61: #include <unistd.h>
1.265 deraadt 62: #include <stdarg.h>
1.1 deraadt 63:
1.265 deraadt 64: #include "xmalloc.h"
1.1 deraadt 65: #include "ssh.h"
1.82 markus 66: #include "ssh2.h"
1.354 markus 67: #include "ssherr.h"
1.1 deraadt 68: #include "packet.h"
1.82 markus 69: #include "log.h"
70: #include "misc.h"
1.265 deraadt 71: #include "buffer.h"
1.14 markus 72: #include "channels.h"
73: #include "compat.h"
1.82 markus 74: #include "canohost.h"
1.64 markus 75: #include "key.h"
76: #include "authfd.h"
1.147 stevesk 77: #include "pathnames.h"
1.1 deraadt 78:
1.121 markus 79: /* -- channel core */
1.12 markus 80:
1.27 markus 81: /*
82: * Pointer to an array containing all allocated channels. The array is
83: * dynamically extended as needed.
84: */
1.113 markus 85: static Channel **channels = NULL;
1.1 deraadt 86:
1.27 markus 87: /*
88: * Size of the channel array. All slots of the array must always be
1.113 markus 89: * initialized (at least the type field); unused slots set to NULL
1.27 markus 90: */
1.209 avsm 91: static u_int channels_alloc = 0;
1.1 deraadt 92:
1.27 markus 93: /*
94: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 95: * updated in channel_new.
1.27 markus 96: */
1.84 markus 97: static int channel_max_fd = 0;
1.1 deraadt 98:
99:
1.121 markus 100: /* -- tcp forwarding */
1.1 deraadt 101:
1.27 markus 102: /*
103: * Data structure for storing which hosts are permitted for forward requests.
104: * The local sides of any remote forwards are stored in this array to prevent
105: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
106: * network (which might be behind a firewall).
107: */
1.336 millert 108: /* XXX: streamlocal wants a path instead of host:port */
109: /* Overload host_to_connect; we could just make this match Forward */
110: /* XXX - can we use listen_host instead of listen_path? */
1.25 markus 111: typedef struct {
1.41 markus 112: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 113: int port_to_connect; /* Connect to 'port'. */
1.333 markus 114: char *listen_host; /* Remote side should listen address. */
1.336 millert 115: char *listen_path; /* Remote side should listen path. */
116: int listen_port; /* Remote side should listen port. */
1.354 markus 117: Channel *downstream; /* Downstream mux*/
1.1 deraadt 118: } ForwardPermission;
119:
1.257 dtucker 120: /* List of all permitted host/port pairs to connect by the user. */
1.305 djm 121: static ForwardPermission *permitted_opens = NULL;
1.121 markus 122:
1.257 dtucker 123: /* List of all permitted host/port pairs to connect by the admin. */
1.305 djm 124: static ForwardPermission *permitted_adm_opens = NULL;
1.257 dtucker 125:
126: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 127: static int num_permitted_opens = 0;
1.257 dtucker 128:
129: /* Number of permitted host/port pair in the array permitted by the admin. */
130: static int num_adm_permitted_opens = 0;
131:
1.314 dtucker 132: /* special-case port number meaning allow any port */
133: #define FWD_PERMIT_ANY_PORT 0
134:
1.351 dtucker 135: /* special-case wildcard meaning allow any host */
136: #define FWD_PERMIT_ANY_HOST "*"
137:
1.27 markus 138: /*
139: * If this is true, all opens are permitted. This is the case on the server
140: * on which we have to trust the client anyway, and the user could do
141: * anything after logging in anyway.
142: */
1.1 deraadt 143: static int all_opens_permitted = 0;
144:
1.121 markus 145:
146: /* -- X11 forwarding */
147:
148: /* Maximum number of fake X11 displays to try. */
149: #define MAX_DISPLAYS 1000
150:
1.219 djm 151: /* Saved X11 local (client) display. */
152: static char *x11_saved_display = NULL;
153:
1.121 markus 154: /* Saved X11 authentication protocol name. */
155: static char *x11_saved_proto = NULL;
156:
157: /* Saved X11 authentication data. This is the real data. */
158: static char *x11_saved_data = NULL;
159: static u_int x11_saved_data_len = 0;
160:
1.347 djm 161: /* Deadline after which all X11 connections are refused */
162: static u_int x11_refuse_time;
163:
1.121 markus 164: /*
165: * Fake X11 authentication data. This is what the server will be sending us;
166: * we should replace any occurrences of this by the real data.
167: */
1.240 deraadt 168: static u_char *x11_fake_data = NULL;
1.121 markus 169: static u_int x11_fake_data_len;
170:
171:
172: /* -- agent forwarding */
173:
174: #define NUM_SOCKS 10
175:
1.82 markus 176: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 177: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 178:
1.121 markus 179: /* helper */
1.127 itojun 180: static void port_open_helper(Channel *c, char *rtype);
1.354 markus 181: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 182:
1.276 djm 183: /* non-blocking connect helpers */
184: static int connect_next(struct channel_connect *);
185: static void channel_connect_ctx_free(struct channel_connect *);
186:
1.121 markus 187: /* -- channel core */
1.41 markus 188:
189: Channel *
1.229 markus 190: channel_by_id(int id)
1.41 markus 191: {
192: Channel *c;
1.113 markus 193:
1.209 avsm 194: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 195: logit("channel_by_id: %d: bad id", id);
1.41 markus 196: return NULL;
197: }
1.113 markus 198: c = channels[id];
199: if (c == NULL) {
1.229 markus 200: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 201: return NULL;
202: }
203: return c;
1.55 markus 204: }
205:
1.354 markus 206: Channel *
207: channel_by_remote_id(int remote_id)
208: {
209: Channel *c;
210: u_int i;
211:
212: for (i = 0; i < channels_alloc; i++) {
213: c = channels[i];
214: if (c != NULL && c->remote_id == remote_id)
215: return c;
216: }
217: return NULL;
218: }
219:
1.27 markus 220: /*
1.229 markus 221: * Returns the channel if it is allowed to receive protocol messages.
222: * Private channels, like listening sockets, may not receive messages.
223: */
224: Channel *
225: channel_lookup(int id)
226: {
227: Channel *c;
228:
229: if ((c = channel_by_id(id)) == NULL)
230: return (NULL);
231:
1.237 deraadt 232: switch (c->type) {
1.229 markus 233: case SSH_CHANNEL_X11_OPEN:
234: case SSH_CHANNEL_LARVAL:
235: case SSH_CHANNEL_CONNECTING:
236: case SSH_CHANNEL_DYNAMIC:
237: case SSH_CHANNEL_OPENING:
238: case SSH_CHANNEL_OPEN:
1.323 dtucker 239: case SSH_CHANNEL_ABANDONED:
1.354 markus 240: case SSH_CHANNEL_MUX_PROXY:
1.229 markus 241: return (c);
242: }
243: logit("Non-public channel %d, type %d.", id, c->type);
244: return (NULL);
245: }
246:
247: /*
1.55 markus 248: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 249: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 250: */
1.127 itojun 251: static void
1.71 markus 252: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 253: int extusage, int nonblock, int is_tty)
1.1 deraadt 254: {
1.25 markus 255: /* Update the maximum file descriptor value. */
1.352 deraadt 256: channel_max_fd = MAXIMUM(channel_max_fd, rfd);
257: channel_max_fd = MAXIMUM(channel_max_fd, wfd);
258: channel_max_fd = MAXIMUM(channel_max_fd, efd);
1.84 markus 259:
1.298 dtucker 260: if (rfd != -1)
261: fcntl(rfd, F_SETFD, FD_CLOEXEC);
262: if (wfd != -1 && wfd != rfd)
263: fcntl(wfd, F_SETFD, FD_CLOEXEC);
264: if (efd != -1 && efd != rfd && efd != wfd)
265: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 266:
1.52 markus 267: c->rfd = rfd;
268: c->wfd = wfd;
269: c->sock = (rfd == wfd) ? rfd : -1;
270: c->efd = efd;
271: c->extended_usage = extusage;
1.71 markus 272:
1.282 dtucker 273: if ((c->isatty = is_tty) != 0)
1.194 markus 274: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 275:
1.71 markus 276: /* enable nonblocking mode */
277: if (nonblock) {
278: if (rfd != -1)
279: set_nonblock(rfd);
280: if (wfd != -1)
281: set_nonblock(wfd);
282: if (efd != -1)
283: set_nonblock(efd);
284: }
1.52 markus 285: }
286:
287: /*
288: * Allocate a new channel object and set its type and socket. This will cause
289: * remote_name to be freed.
290: */
1.113 markus 291: Channel *
1.52 markus 292: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 293: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 294: {
1.209 avsm 295: int found;
296: u_int i;
1.52 markus 297: Channel *c;
1.25 markus 298:
299: /* Do initial allocation if this is the first call. */
300: if (channels_alloc == 0) {
301: channels_alloc = 10;
1.242 djm 302: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 303: for (i = 0; i < channels_alloc; i++)
1.113 markus 304: channels[i] = NULL;
1.25 markus 305: }
306: /* Try to find a free slot where to put the new channel. */
307: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 308: if (channels[i] == NULL) {
1.25 markus 309: /* Found a free slot. */
1.209 avsm 310: found = (int)i;
1.25 markus 311: break;
312: }
1.209 avsm 313: if (found < 0) {
1.27 markus 314: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 315: found = channels_alloc;
1.179 markus 316: if (channels_alloc > 10000)
317: fatal("channel_new: internal error: channels_alloc %d "
318: "too big.", channels_alloc);
1.342 deraadt 319: channels = xreallocarray(channels, channels_alloc + 10,
1.243 djm 320: sizeof(Channel *));
1.195 markus 321: channels_alloc += 10;
1.70 markus 322: debug2("channel: expanding %d", channels_alloc);
1.25 markus 323: for (i = found; i < channels_alloc; i++)
1.113 markus 324: channels[i] = NULL;
1.25 markus 325: }
1.113 markus 326: /* Initialize and return new channel. */
1.242 djm 327: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 328: buffer_init(&c->input);
329: buffer_init(&c->output);
1.41 markus 330: buffer_init(&c->extended);
1.293 djm 331: c->path = NULL;
1.312 djm 332: c->listening_addr = NULL;
333: c->listening_port = 0;
1.159 markus 334: c->ostate = CHAN_OUTPUT_OPEN;
335: c->istate = CHAN_INPUT_OPEN;
336: c->flags = 0;
1.281 djm 337: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.317 djm 338: c->notbefore = 0;
1.25 markus 339: c->self = found;
340: c->type = type;
1.41 markus 341: c->ctype = ctype;
1.51 markus 342: c->local_window = window;
343: c->local_window_max = window;
344: c->local_consumed = 0;
345: c->local_maxpacket = maxpack;
1.25 markus 346: c->remote_id = -1;
1.190 markus 347: c->remote_name = xstrdup(remote_name);
1.41 markus 348: c->remote_window = 0;
349: c->remote_maxpacket = 0;
1.133 markus 350: c->force_drain = 0;
1.149 markus 351: c->single_connection = 0;
1.131 markus 352: c->detach_user = NULL;
1.225 djm 353: c->detach_close = 0;
1.275 djm 354: c->open_confirm = NULL;
355: c->open_confirm_ctx = NULL;
1.65 markus 356: c->input_filter = NULL;
1.231 reyk 357: c->output_filter = NULL;
1.280 djm 358: c->filter_ctx = NULL;
359: c->filter_cleanup = NULL;
1.302 djm 360: c->ctl_chan = -1;
361: c->mux_rcb = NULL;
362: c->mux_ctx = NULL;
1.304 djm 363: c->mux_pause = 0;
1.299 markus 364: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 365: TAILQ_INIT(&c->status_confirms);
1.25 markus 366: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 367: return c;
1.1 deraadt 368: }
1.52 markus 369:
1.132 markus 370: static int
371: channel_find_maxfd(void)
372: {
1.209 avsm 373: u_int i;
374: int max = 0;
1.132 markus 375: Channel *c;
376:
377: for (i = 0; i < channels_alloc; i++) {
378: c = channels[i];
379: if (c != NULL) {
1.352 deraadt 380: max = MAXIMUM(max, c->rfd);
381: max = MAXIMUM(max, c->wfd);
382: max = MAXIMUM(max, c->efd);
1.132 markus 383: }
384: }
385: return max;
386: }
387:
388: int
389: channel_close_fd(int *fdp)
390: {
391: int ret = 0, fd = *fdp;
392:
393: if (fd != -1) {
394: ret = close(fd);
395: *fdp = -1;
396: if (fd == channel_max_fd)
397: channel_max_fd = channel_find_maxfd();
398: }
399: return ret;
400: }
401:
1.52 markus 402: /* Close all channel fd/socket. */
1.127 itojun 403: static void
1.52 markus 404: channel_close_fds(Channel *c)
405: {
1.132 markus 406: channel_close_fd(&c->sock);
407: channel_close_fd(&c->rfd);
408: channel_close_fd(&c->wfd);
409: channel_close_fd(&c->efd);
1.121 markus 410: }
411:
412: /* Free the channel and close its fd/socket. */
413: void
414: channel_free(Channel *c)
415: {
416: char *s;
1.209 avsm 417: u_int i, n;
1.354 markus 418: Channel *other;
1.275 djm 419: struct channel_confirm *cc;
1.121 markus 420:
1.354 markus 421: for (n = 0, i = 0; i < channels_alloc; i++) {
422: if ((other = channels[i]) != NULL) {
1.121 markus 423: n++;
1.354 markus 424:
425: /* detach from mux client and prepare for closing */
426: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
427: other->type == SSH_CHANNEL_MUX_PROXY &&
428: other->mux_ctx == c) {
429: other->mux_ctx = NULL;
430: other->type = SSH_CHANNEL_OPEN;
431: other->istate = CHAN_INPUT_CLOSED;
432: other->ostate = CHAN_OUTPUT_CLOSED;
433: }
434: }
435: }
1.209 avsm 436: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 437: c->remote_name ? c->remote_name : "???", n);
438:
1.354 markus 439: /* XXX more MUX cleanup: remove remote forwardings */
440: if (c->type == SSH_CHANNEL_MUX_CLIENT) {
441: for (i = 0; i < (u_int)num_permitted_opens; i++) {
442: if (permitted_opens[i].downstream != c)
443: continue;
444: /* cancel on the server, since mux client is gone */
445: debug("channel %d: cleanup remote forward for %s:%u",
446: c->self,
447: permitted_opens[i].listen_host,
448: permitted_opens[i].listen_port);
449: packet_start(SSH2_MSG_GLOBAL_REQUEST);
450: packet_put_cstring("cancel-tcpip-forward");
451: packet_put_char(0);
452: packet_put_cstring(channel_rfwd_bind_host(
453: permitted_opens[i].listen_host));
454: packet_put_int(permitted_opens[i].listen_port);
455: packet_send();
456: /* unregister */
457: permitted_opens[i].listen_port = 0;
458: permitted_opens[i].port_to_connect = 0;
459: free(permitted_opens[i].host_to_connect);
460: permitted_opens[i].host_to_connect = NULL;
461: free(permitted_opens[i].listen_host);
462: permitted_opens[i].listen_host = NULL;
463: permitted_opens[i].listen_path = NULL;
464: permitted_opens[i].downstream = NULL;
465: }
466: }
467:
1.121 markus 468: s = channel_open_message();
1.194 markus 469: debug3("channel %d: status: %s", c->self, s);
1.321 djm 470: free(s);
1.121 markus 471:
472: channel_close_fds(c);
473: buffer_free(&c->input);
474: buffer_free(&c->output);
475: buffer_free(&c->extended);
1.321 djm 476: free(c->remote_name);
477: c->remote_name = NULL;
478: free(c->path);
479: c->path = NULL;
480: free(c->listening_addr);
481: c->listening_addr = NULL;
1.275 djm 482: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
483: if (cc->abandon_cb != NULL)
484: cc->abandon_cb(c, cc->ctx);
485: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 486: explicit_bzero(cc, sizeof(*cc));
1.321 djm 487: free(cc);
1.275 djm 488: }
1.280 djm 489: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
490: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 491: channels[c->self] = NULL;
1.321 djm 492: free(c);
1.121 markus 493: }
494:
495: void
1.126 markus 496: channel_free_all(void)
1.121 markus 497: {
1.209 avsm 498: u_int i;
1.121 markus 499:
1.126 markus 500: for (i = 0; i < channels_alloc; i++)
501: if (channels[i] != NULL)
502: channel_free(channels[i]);
1.131 markus 503: }
504:
1.121 markus 505: /*
506: * Closes the sockets/fds of all channels. This is used to close extra file
507: * descriptors after a fork.
508: */
509: void
1.142 itojun 510: channel_close_all(void)
1.121 markus 511: {
1.209 avsm 512: u_int i;
1.121 markus 513:
514: for (i = 0; i < channels_alloc; i++)
515: if (channels[i] != NULL)
516: channel_close_fds(channels[i]);
517: }
518:
519: /*
1.131 markus 520: * Stop listening to channels.
521: */
522: void
523: channel_stop_listening(void)
524: {
1.209 avsm 525: u_int i;
1.131 markus 526: Channel *c;
527:
528: for (i = 0; i < channels_alloc; i++) {
529: c = channels[i];
530: if (c != NULL) {
531: switch (c->type) {
532: case SSH_CHANNEL_AUTH_SOCKET:
533: case SSH_CHANNEL_PORT_LISTENER:
534: case SSH_CHANNEL_RPORT_LISTENER:
535: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 536: case SSH_CHANNEL_UNIX_LISTENER:
537: case SSH_CHANNEL_RUNIX_LISTENER:
1.132 markus 538: channel_close_fd(&c->sock);
1.131 markus 539: channel_free(c);
540: break;
541: }
542: }
543: }
544: }
545:
546: /*
1.121 markus 547: * Returns true if no channel has too much buffered data, and false if one or
548: * more channel is overfull.
549: */
550: int
1.142 itojun 551: channel_not_very_much_buffered_data(void)
1.121 markus 552: {
553: u_int i;
554: Channel *c;
555:
556: for (i = 0; i < channels_alloc; i++) {
557: c = channels[i];
558: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
559: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 560: debug2("channel %d: big output buffer %u > %u",
1.136 markus 561: c->self, buffer_len(&c->output),
562: packet_get_maxsize());
1.121 markus 563: return 0;
564: }
565: }
566: }
567: return 1;
568: }
569:
570: /* Returns true if any channel is still open. */
571: int
1.142 itojun 572: channel_still_open(void)
1.121 markus 573: {
1.209 avsm 574: u_int i;
1.121 markus 575: Channel *c;
576:
577: for (i = 0; i < channels_alloc; i++) {
578: c = channels[i];
579: if (c == NULL)
580: continue;
581: switch (c->type) {
582: case SSH_CHANNEL_X11_LISTENER:
583: case SSH_CHANNEL_PORT_LISTENER:
584: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 585: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 586: case SSH_CHANNEL_CLOSED:
587: case SSH_CHANNEL_AUTH_SOCKET:
588: case SSH_CHANNEL_DYNAMIC:
589: case SSH_CHANNEL_CONNECTING:
590: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 591: case SSH_CHANNEL_ABANDONED:
1.336 millert 592: case SSH_CHANNEL_UNIX_LISTENER:
593: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 594: continue;
595: case SSH_CHANNEL_LARVAL:
596: continue;
597: case SSH_CHANNEL_OPENING:
598: case SSH_CHANNEL_OPEN:
599: case SSH_CHANNEL_X11_OPEN:
1.302 djm 600: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 601: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 602: return 1;
603: default:
1.358 djm 604: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 605: /* NOTREACHED */
606: }
607: }
608: return 0;
609: }
610:
611: /* Returns the id of an open channel suitable for keepaliving */
612: int
1.142 itojun 613: channel_find_open(void)
1.121 markus 614: {
1.209 avsm 615: u_int i;
1.121 markus 616: Channel *c;
617:
618: for (i = 0; i < channels_alloc; i++) {
619: c = channels[i];
1.206 djm 620: if (c == NULL || c->remote_id < 0)
1.121 markus 621: continue;
622: switch (c->type) {
623: case SSH_CHANNEL_CLOSED:
624: case SSH_CHANNEL_DYNAMIC:
625: case SSH_CHANNEL_X11_LISTENER:
626: case SSH_CHANNEL_PORT_LISTENER:
627: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 628: case SSH_CHANNEL_MUX_LISTENER:
629: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 630: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 631: case SSH_CHANNEL_OPENING:
632: case SSH_CHANNEL_CONNECTING:
633: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 634: case SSH_CHANNEL_ABANDONED:
1.336 millert 635: case SSH_CHANNEL_UNIX_LISTENER:
636: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 637: continue;
638: case SSH_CHANNEL_LARVAL:
639: case SSH_CHANNEL_AUTH_SOCKET:
640: case SSH_CHANNEL_OPEN:
641: case SSH_CHANNEL_X11_OPEN:
642: return i;
643: default:
1.358 djm 644: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 645: /* NOTREACHED */
646: }
647: }
648: return -1;
649: }
650:
651: /*
652: * Returns a message describing the currently open forwarded connections,
653: * suitable for sending to the client. The message contains crlf pairs for
654: * newlines.
655: */
656: char *
1.142 itojun 657: channel_open_message(void)
1.121 markus 658: {
659: Buffer buffer;
660: Channel *c;
661: char buf[1024], *cp;
1.209 avsm 662: u_int i;
1.121 markus 663:
664: buffer_init(&buffer);
665: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
666: buffer_append(&buffer, buf, strlen(buf));
667: for (i = 0; i < channels_alloc; i++) {
668: c = channels[i];
669: if (c == NULL)
670: continue;
671: switch (c->type) {
672: case SSH_CHANNEL_X11_LISTENER:
673: case SSH_CHANNEL_PORT_LISTENER:
674: case SSH_CHANNEL_RPORT_LISTENER:
675: case SSH_CHANNEL_CLOSED:
676: case SSH_CHANNEL_AUTH_SOCKET:
677: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 678: case SSH_CHANNEL_ABANDONED:
1.302 djm 679: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 680: case SSH_CHANNEL_UNIX_LISTENER:
681: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 682: continue;
683: case SSH_CHANNEL_LARVAL:
684: case SSH_CHANNEL_OPENING:
685: case SSH_CHANNEL_CONNECTING:
686: case SSH_CHANNEL_DYNAMIC:
687: case SSH_CHANNEL_OPEN:
688: case SSH_CHANNEL_X11_OPEN:
1.354 markus 689: case SSH_CHANNEL_MUX_PROXY:
690: case SSH_CHANNEL_MUX_CLIENT:
1.204 djm 691: snprintf(buf, sizeof buf,
1.348 djm 692: " #%d %.300s (t%d r%d i%u/%d o%u/%d fd %d/%d cc %d)\r\n",
1.121 markus 693: c->self, c->remote_name,
694: c->type, c->remote_id,
695: c->istate, buffer_len(&c->input),
696: c->ostate, buffer_len(&c->output),
1.302 djm 697: c->rfd, c->wfd, c->ctl_chan);
1.121 markus 698: buffer_append(&buffer, buf, strlen(buf));
699: continue;
700: default:
701: fatal("channel_open_message: bad channel type %d", c->type);
702: /* NOTREACHED */
703: }
704: }
705: buffer_append(&buffer, "\0", 1);
1.337 djm 706: cp = xstrdup((char *)buffer_ptr(&buffer));
1.121 markus 707: buffer_free(&buffer);
708: return cp;
709: }
710:
711: void
712: channel_send_open(int id)
713: {
714: Channel *c = channel_lookup(id);
1.180 deraadt 715:
1.121 markus 716: if (c == NULL) {
1.188 itojun 717: logit("channel_send_open: %d: bad id", id);
1.121 markus 718: return;
719: }
1.184 markus 720: debug2("channel %d: send open", id);
1.121 markus 721: packet_start(SSH2_MSG_CHANNEL_OPEN);
722: packet_put_cstring(c->ctype);
723: packet_put_int(c->self);
724: packet_put_int(c->local_window);
725: packet_put_int(c->local_maxpacket);
726: packet_send();
727: }
728:
729: void
1.184 markus 730: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 731: {
1.184 markus 732: Channel *c = channel_lookup(id);
1.180 deraadt 733:
1.121 markus 734: if (c == NULL) {
1.188 itojun 735: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 736: return;
737: }
1.204 djm 738: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 739: packet_start(SSH2_MSG_CHANNEL_REQUEST);
740: packet_put_int(c->remote_id);
741: packet_put_cstring(service);
742: packet_put_char(wantconfirm);
743: }
1.241 deraadt 744:
1.121 markus 745: void
1.275 djm 746: channel_register_status_confirm(int id, channel_confirm_cb *cb,
747: channel_confirm_abandon_cb *abandon_cb, void *ctx)
748: {
749: struct channel_confirm *cc;
750: Channel *c;
751:
752: if ((c = channel_lookup(id)) == NULL)
753: fatal("channel_register_expect: %d: bad id", id);
754:
1.327 djm 755: cc = xcalloc(1, sizeof(*cc));
1.275 djm 756: cc->cb = cb;
757: cc->abandon_cb = abandon_cb;
758: cc->ctx = ctx;
759: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
760: }
761:
762: void
1.304 djm 763: channel_register_open_confirm(int id, channel_open_fn *fn, void *ctx)
1.121 markus 764: {
765: Channel *c = channel_lookup(id);
1.180 deraadt 766:
1.121 markus 767: if (c == NULL) {
1.287 stevesk 768: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 769: return;
770: }
1.275 djm 771: c->open_confirm = fn;
772: c->open_confirm_ctx = ctx;
1.121 markus 773: }
1.241 deraadt 774:
1.121 markus 775: void
1.225 djm 776: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 777: {
1.229 markus 778: Channel *c = channel_by_id(id);
1.180 deraadt 779:
1.121 markus 780: if (c == NULL) {
1.188 itojun 781: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 782: return;
783: }
1.131 markus 784: c->detach_user = fn;
1.225 djm 785: c->detach_close = do_close;
1.121 markus 786: }
1.241 deraadt 787:
1.121 markus 788: void
789: channel_cancel_cleanup(int id)
790: {
1.229 markus 791: Channel *c = channel_by_id(id);
1.180 deraadt 792:
1.121 markus 793: if (c == NULL) {
1.188 itojun 794: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 795: return;
1.52 markus 796: }
1.131 markus 797: c->detach_user = NULL;
1.225 djm 798: c->detach_close = 0;
1.121 markus 799: }
1.241 deraadt 800:
1.121 markus 801: void
1.231 reyk 802: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 803: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 804: {
805: Channel *c = channel_lookup(id);
1.180 deraadt 806:
1.121 markus 807: if (c == NULL) {
1.188 itojun 808: logit("channel_register_filter: %d: bad id", id);
1.121 markus 809: return;
1.52 markus 810: }
1.231 reyk 811: c->input_filter = ifn;
812: c->output_filter = ofn;
1.279 djm 813: c->filter_ctx = ctx;
1.280 djm 814: c->filter_cleanup = cfn;
1.52 markus 815: }
816:
1.49 markus 817: void
1.121 markus 818: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 819: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 820: {
1.121 markus 821: Channel *c = channel_lookup(id);
1.180 deraadt 822:
1.121 markus 823: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
824: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 825: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 826: c->type = SSH_CHANNEL_OPEN;
1.168 markus 827: c->local_window = c->local_window_max = window_max;
1.121 markus 828: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
829: packet_put_int(c->remote_id);
830: packet_put_int(c->local_window);
831: packet_send();
1.1 deraadt 832: }
833:
1.27 markus 834: /*
1.41 markus 835: * 'channel_pre*' are called just before select() to add any bits relevant to
836: * channels in the select bitmasks.
837: */
838: /*
839: * 'channel_post*': perform any appropriate operations for channels which
840: * have events pending.
1.27 markus 841: */
1.237 deraadt 842: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 843: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
844: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
845:
1.259 stevesk 846: /* ARGSUSED */
1.127 itojun 847: static void
1.237 deraadt 848: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 849: {
850: FD_SET(c->sock, readset);
851: }
852:
1.259 stevesk 853: /* ARGSUSED */
1.127 itojun 854: static void
1.237 deraadt 855: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 856: {
857: debug3("channel %d: waiting for connection", c->self);
858: FD_SET(c->sock, writeset);
859: }
860:
1.127 itojun 861: static void
1.237 deraadt 862: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 863: {
1.44 markus 864: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 865: c->remote_window > 0 &&
866: buffer_len(&c->input) < c->remote_window &&
1.250 djm 867: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 868: FD_SET(c->rfd, readset);
869: if (c->ostate == CHAN_OUTPUT_OPEN ||
870: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
871: if (buffer_len(&c->output) > 0) {
872: FD_SET(c->wfd, writeset);
873: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 874: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 875: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
876: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 877: else
878: chan_obuf_empty(c);
1.44 markus 879: }
880: }
881: /** XXX check close conditions, too */
1.358 djm 882: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
883: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 884: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
885: buffer_len(&c->extended) > 0)
886: FD_SET(c->efd, writeset);
1.306 djm 887: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
888: (c->extended_usage == CHAN_EXTENDED_READ ||
889: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 890: buffer_len(&c->extended) < c->remote_window)
891: FD_SET(c->efd, readset);
892: }
1.204 djm 893: /* XXX: What about efd? races? */
1.44 markus 894: }
895:
1.41 markus 896: /*
897: * This is a special state for X11 authentication spoofing. An opened X11
898: * connection (when authentication spoofing is being done) remains in this
899: * state until the first packet has been completely read. The authentication
900: * data in that packet is then substituted by the real data if it matches the
901: * fake data, and the channel is put into normal mode.
1.51 markus 902: * XXX All this happens at the client side.
1.121 markus 903: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 904: */
1.127 itojun 905: static int
1.121 markus 906: x11_open_helper(Buffer *b)
1.1 deraadt 907: {
1.77 markus 908: u_char *ucp;
909: u_int proto_len, data_len;
1.25 markus 910:
1.347 djm 911: /* Is this being called after the refusal deadline? */
912: if (x11_refuse_time != 0 && (u_int)monotime() >= x11_refuse_time) {
913: verbose("Rejected X11 connection after ForwardX11Timeout "
914: "expired");
915: return -1;
916: }
917:
1.41 markus 918: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 919: if (buffer_len(b) < 12)
1.41 markus 920: return 0;
921:
922: /* Parse the lengths of variable-length fields. */
1.155 stevesk 923: ucp = buffer_ptr(b);
1.41 markus 924: if (ucp[0] == 0x42) { /* Byte order MSB first. */
925: proto_len = 256 * ucp[6] + ucp[7];
926: data_len = 256 * ucp[8] + ucp[9];
927: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
928: proto_len = ucp[6] + 256 * ucp[7];
929: data_len = ucp[8] + 256 * ucp[9];
930: } else {
1.194 markus 931: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 932: ucp[0]);
1.41 markus 933: return -1;
934: }
935:
936: /* Check if the whole packet is in buffer. */
1.121 markus 937: if (buffer_len(b) <
1.41 markus 938: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
939: return 0;
940:
941: /* Check if authentication protocol matches. */
942: if (proto_len != strlen(x11_saved_proto) ||
943: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 944: debug2("X11 connection uses different authentication protocol.");
1.41 markus 945: return -1;
946: }
947: /* Check if authentication data matches our fake data. */
948: if (data_len != x11_fake_data_len ||
1.308 djm 949: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.41 markus 950: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 951: debug2("X11 auth data does not match fake data.");
1.41 markus 952: return -1;
953: }
954: /* Check fake data length */
955: if (x11_fake_data_len != x11_saved_data_len) {
956: error("X11 fake_data_len %d != saved_data_len %d",
957: x11_fake_data_len, x11_saved_data_len);
958: return -1;
959: }
960: /*
961: * Received authentication protocol and data match
962: * our fake data. Substitute the fake data with real
963: * data.
964: */
965: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
966: x11_saved_data, x11_saved_data_len);
967: return 1;
968: }
969:
1.127 itojun 970: static void
1.237 deraadt 971: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 972: {
1.121 markus 973: int ret = x11_open_helper(&c->output);
1.133 markus 974:
975: /* c->force_drain = 1; */
976:
1.41 markus 977: if (ret == 1) {
978: c->type = SSH_CHANNEL_OPEN;
1.157 markus 979: channel_pre_open(c, readset, writeset);
1.41 markus 980: } else if (ret == -1) {
1.188 itojun 981: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 982: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 983: chan_read_failed(c);
984: buffer_clear(&c->input);
985: chan_ibuf_empty(c);
986: buffer_clear(&c->output);
1.358 djm 987: chan_write_failed(c);
1.194 markus 988: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 989: }
990: }
1.25 markus 991:
1.302 djm 992: static void
993: channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
994: {
1.304 djm 995: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.302 djm 996: buffer_check_alloc(&c->input, CHAN_RBUF))
997: FD_SET(c->rfd, readset);
998: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
999: /* clear buffer immediately (discard any partial packet) */
1000: buffer_clear(&c->input);
1001: chan_ibuf_empty(c);
1002: /* Start output drain. XXX just kill chan? */
1003: chan_rcvd_oclose(c);
1004: }
1005: if (c->ostate == CHAN_OUTPUT_OPEN ||
1006: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1007: if (buffer_len(&c->output) > 0)
1008: FD_SET(c->wfd, writeset);
1009: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1010: chan_obuf_empty(c);
1011: }
1012: }
1013:
1.104 markus 1014: /* try to decode a socks4 header */
1.259 stevesk 1015: /* ARGSUSED */
1.127 itojun 1016: static int
1.237 deraadt 1017: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 1018: {
1.181 markus 1019: char *p, *host;
1.292 djm 1020: u_int len, have, i, found, need;
1.148 deraadt 1021: char username[256];
1.103 markus 1022: struct {
1023: u_int8_t version;
1024: u_int8_t command;
1025: u_int16_t dest_port;
1.104 markus 1026: struct in_addr dest_addr;
1.103 markus 1027: } s4_req, s4_rsp;
1028:
1.104 markus 1029: debug2("channel %d: decode socks4", c->self);
1.109 markus 1030:
1031: have = buffer_len(&c->input);
1032: len = sizeof(s4_req);
1033: if (have < len)
1034: return 0;
1.337 djm 1035: p = (char *)buffer_ptr(&c->input);
1.292 djm 1036:
1037: need = 1;
1038: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1039: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1040: debug2("channel %d: socks4a request", c->self);
1041: /* ... and needs an extra string (the hostname) */
1042: need = 2;
1043: }
1044: /* Check for terminating NUL on the string(s) */
1.109 markus 1045: for (found = 0, i = len; i < have; i++) {
1046: if (p[i] == '\0') {
1.292 djm 1047: found++;
1048: if (found == need)
1049: break;
1.109 markus 1050: }
1051: if (i > 1024) {
1052: /* the peer is probably sending garbage */
1053: debug("channel %d: decode socks4: too long",
1054: c->self);
1055: return -1;
1056: }
1057: }
1.292 djm 1058: if (found < need)
1.109 markus 1059: return 0;
1.103 markus 1060: buffer_get(&c->input, (char *)&s4_req.version, 1);
1061: buffer_get(&c->input, (char *)&s4_req.command, 1);
1062: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1063: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1064: have = buffer_len(&c->input);
1.337 djm 1065: p = (char *)buffer_ptr(&c->input);
1.364 djm 1066: if (memchr(p, '\0', have) == NULL) {
1067: error("channel %d: decode socks4: user not nul terminated",
1.331 djm 1068: c->self);
1.364 djm 1069: return -1;
1070: }
1.103 markus 1071: len = strlen(p);
1.106 markus 1072: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1073: len++; /* trailing '\0' */
1.103 markus 1074: if (len > have)
1.104 markus 1075: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1076: c->self, len, have);
1077: strlcpy(username, p, sizeof(username));
1078: buffer_consume(&c->input, len);
1079:
1.321 djm 1080: free(c->path);
1081: c->path = NULL;
1.292 djm 1082: if (need == 1) { /* SOCKS4: one string */
1083: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1084: c->path = xstrdup(host);
1.292 djm 1085: } else { /* SOCKS4A: two strings */
1086: have = buffer_len(&c->input);
1.337 djm 1087: p = (char *)buffer_ptr(&c->input);
1.364 djm 1088: if (memchr(p, '\0', have) == NULL) {
1089: error("channel %d: decode socks4a: host not nul "
1090: "terminated", c->self);
1091: return -1;
1092: }
1.292 djm 1093: len = strlen(p);
1094: debug2("channel %d: decode socks4a: host %s/%d",
1095: c->self, p, len);
1096: len++; /* trailing '\0' */
1.293 djm 1097: if (len > NI_MAXHOST) {
1.292 djm 1098: error("channel %d: hostname \"%.100s\" too long",
1099: c->self, p);
1100: return -1;
1101: }
1.293 djm 1102: c->path = xstrdup(p);
1.292 djm 1103: buffer_consume(&c->input, len);
1104: }
1.103 markus 1105: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1106:
1.194 markus 1107: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1108: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1109:
1.104 markus 1110: if (s4_req.command != 1) {
1.292 djm 1111: debug("channel %d: cannot handle: %s cn %d",
1112: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1113: return -1;
1.103 markus 1114: }
1.104 markus 1115: s4_rsp.version = 0; /* vn: 0 for reply */
1116: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1117: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1118: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1119: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1120: return 1;
1121: }
1122:
1.193 markus 1123: /* try to decode a socks5 header */
1124: #define SSH_SOCKS5_AUTHDONE 0x1000
1125: #define SSH_SOCKS5_NOAUTH 0x00
1126: #define SSH_SOCKS5_IPV4 0x01
1127: #define SSH_SOCKS5_DOMAIN 0x03
1128: #define SSH_SOCKS5_IPV6 0x04
1129: #define SSH_SOCKS5_CONNECT 0x01
1130: #define SSH_SOCKS5_SUCCESS 0x00
1131:
1.259 stevesk 1132: /* ARGSUSED */
1.193 markus 1133: static int
1.237 deraadt 1134: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1135: {
1136: struct {
1137: u_int8_t version;
1138: u_int8_t command;
1139: u_int8_t reserved;
1140: u_int8_t atyp;
1141: } s5_req, s5_rsp;
1142: u_int16_t dest_port;
1.324 djm 1143: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1144: u_char *p;
1.252 djm 1145: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1146:
1147: debug2("channel %d: decode socks5", c->self);
1148: p = buffer_ptr(&c->input);
1149: if (p[0] != 0x05)
1150: return -1;
1151: have = buffer_len(&c->input);
1152: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1153: /* format: ver | nmethods | methods */
1.198 djm 1154: if (have < 2)
1.193 markus 1155: return 0;
1156: nmethods = p[1];
1157: if (have < nmethods + 2)
1158: return 0;
1159: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1160: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1161: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1162: found = 1;
1163: break;
1164: }
1165: }
1166: if (!found) {
1167: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1168: c->self);
1169: return -1;
1170: }
1171: buffer_consume(&c->input, nmethods + 2);
1172: buffer_put_char(&c->output, 0x05); /* version */
1173: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1174: FD_SET(c->sock, writeset);
1175: c->flags |= SSH_SOCKS5_AUTHDONE;
1176: debug2("channel %d: socks5 auth done", c->self);
1177: return 0; /* need more */
1178: }
1179: debug2("channel %d: socks5 post auth", c->self);
1180: if (have < sizeof(s5_req)+1)
1181: return 0; /* need more */
1.247 deraadt 1182: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1183: if (s5_req.version != 0x05 ||
1184: s5_req.command != SSH_SOCKS5_CONNECT ||
1185: s5_req.reserved != 0x00) {
1.194 markus 1186: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1187: return -1;
1188: }
1.213 deraadt 1189: switch (s5_req.atyp){
1.193 markus 1190: case SSH_SOCKS5_IPV4:
1191: addrlen = 4;
1192: af = AF_INET;
1193: break;
1194: case SSH_SOCKS5_DOMAIN:
1195: addrlen = p[sizeof(s5_req)];
1196: af = -1;
1197: break;
1198: case SSH_SOCKS5_IPV6:
1199: addrlen = 16;
1200: af = AF_INET6;
1201: break;
1202: default:
1.194 markus 1203: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1204: return -1;
1205: }
1.252 djm 1206: need = sizeof(s5_req) + addrlen + 2;
1207: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1208: need++;
1209: if (have < need)
1.193 markus 1210: return 0;
1211: buffer_consume(&c->input, sizeof(s5_req));
1212: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1213: buffer_consume(&c->input, 1); /* host string length */
1.324 djm 1214: buffer_get(&c->input, &dest_addr, addrlen);
1.193 markus 1215: buffer_get(&c->input, (char *)&dest_port, 2);
1216: dest_addr[addrlen] = '\0';
1.321 djm 1217: free(c->path);
1218: c->path = NULL;
1.293 djm 1219: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1220: if (addrlen >= NI_MAXHOST) {
1.293 djm 1221: error("channel %d: dynamic request: socks5 hostname "
1222: "\"%.100s\" too long", c->self, dest_addr);
1223: return -1;
1224: }
1225: c->path = xstrdup(dest_addr);
1226: } else {
1227: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1228: return -1;
1229: c->path = xstrdup(ntop);
1230: }
1.193 markus 1231: c->host_port = ntohs(dest_port);
1.198 djm 1232:
1.194 markus 1233: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1234: c->self, c->path, c->host_port, s5_req.command);
1235:
1236: s5_rsp.version = 0x05;
1237: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1238: s5_rsp.reserved = 0; /* ignored */
1239: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1240: dest_port = 0; /* ignored */
1241:
1.246 deraadt 1242: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1.325 djm 1243: buffer_put_int(&c->output, ntohl(INADDR_ANY)); /* bind address */
1.246 deraadt 1244: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1245: return 1;
1.301 dtucker 1246: }
1247:
1248: Channel *
1.302 djm 1249: channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
1250: int in, int out)
1.301 dtucker 1251: {
1252: Channel *c;
1253:
1254: debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
1255: port_to_connect);
1256:
1257: c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
1258: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1259: 0, "stdio-forward", /*nonblock*/0);
1260:
1261: c->path = xstrdup(host_to_connect);
1262: c->host_port = port_to_connect;
1263: c->listening_port = 0;
1264: c->force_drain = 1;
1265:
1266: channel_register_fds(c, in, out, -1, 0, 1, 0);
1267: port_open_helper(c, "direct-tcpip");
1268:
1269: return c;
1.193 markus 1270: }
1271:
1.104 markus 1272: /* dynamic port forwarding */
1.127 itojun 1273: static void
1.237 deraadt 1274: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1275: {
1276: u_char *p;
1.217 djm 1277: u_int have;
1278: int ret;
1.103 markus 1279:
1.104 markus 1280: have = buffer_len(&c->input);
1281: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1282: /* buffer_dump(&c->input); */
1.104 markus 1283: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1284: if (have < 3) {
1.104 markus 1285: /* need more */
1286: FD_SET(c->sock, readset);
1287: return;
1288: }
1289: /* try to guess the protocol */
1290: p = buffer_ptr(&c->input);
1291: switch (p[0]) {
1292: case 0x04:
1293: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1294: break;
1295: case 0x05:
1296: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1297: break;
1298: default:
1299: ret = -1;
1300: break;
1301: }
1302: if (ret < 0) {
1.113 markus 1303: chan_mark_dead(c);
1.104 markus 1304: } else if (ret == 0) {
1305: debug2("channel %d: pre_dynamic: need more", c->self);
1306: /* need more */
1307: FD_SET(c->sock, readset);
1308: } else {
1309: /* switch to the next state */
1310: c->type = SSH_CHANNEL_OPENING;
1311: port_open_helper(c, "direct-tcpip");
1312: }
1.103 markus 1313: }
1314:
1.41 markus 1315: /* This is our fake X11 server socket. */
1.259 stevesk 1316: /* ARGSUSED */
1.127 itojun 1317: static void
1.237 deraadt 1318: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1319: {
1.113 markus 1320: Channel *nc;
1.285 djm 1321: struct sockaddr_storage addr;
1.320 markus 1322: int newsock, oerrno;
1.41 markus 1323: socklen_t addrlen;
1.85 markus 1324: char buf[16384], *remote_ipaddr;
1.51 markus 1325: int remote_port;
1.25 markus 1326:
1.41 markus 1327: if (FD_ISSET(c->sock, readset)) {
1328: debug("X11 connection requested.");
1329: addrlen = sizeof(addr);
1.285 djm 1330: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1331: if (c->single_connection) {
1.320 markus 1332: oerrno = errno;
1.194 markus 1333: debug2("single_connection: closing X11 listener.");
1.149 markus 1334: channel_close_fd(&c->sock);
1335: chan_mark_dead(c);
1.320 markus 1336: errno = oerrno;
1.149 markus 1337: }
1.41 markus 1338: if (newsock < 0) {
1.320 markus 1339: if (errno != EINTR && errno != EWOULDBLOCK &&
1340: errno != ECONNABORTED)
1341: error("accept: %.100s", strerror(errno));
1.317 djm 1342: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1343: c->notbefore = monotime() + 1;
1.41 markus 1344: return;
1345: }
1.162 stevesk 1346: set_nodelay(newsock);
1.85 markus 1347: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1348: remote_port = get_peer_port(newsock);
1.41 markus 1349: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1350: remote_ipaddr, remote_port);
1.51 markus 1351:
1.113 markus 1352: nc = channel_new("accepted x11 socket",
1.51 markus 1353: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1354: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.358 djm 1355: packet_start(SSH2_MSG_CHANNEL_OPEN);
1356: packet_put_cstring("x11");
1357: packet_put_int(nc->self);
1358: packet_put_int(nc->local_window_max);
1359: packet_put_int(nc->local_maxpacket);
1360: /* originator ipaddr and port */
1361: packet_put_cstring(remote_ipaddr);
1362: if (datafellows & SSH_BUG_X11FWD) {
1363: debug2("ssh2 x11 bug compat mode");
1.51 markus 1364: } else {
1.358 djm 1365: packet_put_int(remote_port);
1.51 markus 1366: }
1.358 djm 1367: packet_send();
1.321 djm 1368: free(remote_ipaddr);
1.41 markus 1369: }
1370: }
1.25 markus 1371:
1.127 itojun 1372: static void
1.103 markus 1373: port_open_helper(Channel *c, char *rtype)
1374: {
1375: char buf[1024];
1.328 djm 1376: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1377: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1378: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1379: int remote_port = get_peer_port(c->sock);
1.303 djm 1380:
1381: if (remote_port == -1) {
1382: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1383: free(remote_ipaddr);
1.303 djm 1384: remote_ipaddr = xstrdup("127.0.0.1");
1385: remote_port = 65535;
1386: }
1.103 markus 1387:
1388: snprintf(buf, sizeof buf,
1389: "%s: listening port %d for %.100s port %d, "
1.328 djm 1390: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1391: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1392: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1393:
1.321 djm 1394: free(c->remote_name);
1.103 markus 1395: c->remote_name = xstrdup(buf);
1396:
1.358 djm 1397: packet_start(SSH2_MSG_CHANNEL_OPEN);
1398: packet_put_cstring(rtype);
1399: packet_put_int(c->self);
1400: packet_put_int(c->local_window_max);
1401: packet_put_int(c->local_maxpacket);
1402: if (strcmp(rtype, "direct-tcpip") == 0) {
1403: /* target host, port */
1404: packet_put_cstring(c->path);
1405: packet_put_int(c->host_port);
1406: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1407: /* target path */
1408: packet_put_cstring(c->path);
1409: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1410: /* listen path */
1411: packet_put_cstring(c->path);
1.103 markus 1412: } else {
1.358 djm 1413: /* listen address, port */
1.103 markus 1414: packet_put_cstring(c->path);
1.358 djm 1415: packet_put_int(local_port);
1416: }
1417: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1418: /* reserved for future owner/mode info */
1419: packet_put_cstring("");
1420: } else {
1421: /* originator host and port */
1422: packet_put_cstring(remote_ipaddr);
1423: packet_put_int((u_int)remote_port);
1.103 markus 1424: }
1.358 djm 1425: packet_send();
1.321 djm 1426: free(remote_ipaddr);
1.328 djm 1427: free(local_ipaddr);
1.103 markus 1428: }
1429:
1.226 djm 1430: static void
1431: channel_set_reuseaddr(int fd)
1432: {
1433: int on = 1;
1434:
1435: /*
1436: * Set socket options.
1437: * Allow local port reuse in TIME_WAIT.
1438: */
1439: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1440: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1.347 djm 1441: }
1442:
1443: void
1444: channel_set_x11_refuse_time(u_int refuse_time)
1445: {
1446: x11_refuse_time = refuse_time;
1.226 djm 1447: }
1448:
1.41 markus 1449: /*
1450: * This socket is listening for connections to a forwarded TCP/IP port.
1451: */
1.259 stevesk 1452: /* ARGSUSED */
1.127 itojun 1453: static void
1.237 deraadt 1454: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1455: {
1.103 markus 1456: Channel *nc;
1.285 djm 1457: struct sockaddr_storage addr;
1.113 markus 1458: int newsock, nextstate;
1.41 markus 1459: socklen_t addrlen;
1.103 markus 1460: char *rtype;
1.73 markus 1461:
1.41 markus 1462: if (FD_ISSET(c->sock, readset)) {
1463: debug("Connection to port %d forwarding "
1464: "to %.100s port %d requested.",
1465: c->listening_port, c->path, c->host_port);
1.103 markus 1466:
1.137 markus 1467: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1468: nextstate = SSH_CHANNEL_OPENING;
1469: rtype = "forwarded-tcpip";
1.336 millert 1470: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1471: nextstate = SSH_CHANNEL_OPENING;
1472: rtype = "forwarded-streamlocal@openssh.com";
1473: } else if (c->host_port == PORT_STREAMLOCAL) {
1474: nextstate = SSH_CHANNEL_OPENING;
1475: rtype = "direct-streamlocal@openssh.com";
1476: } else if (c->host_port == 0) {
1477: nextstate = SSH_CHANNEL_DYNAMIC;
1478: rtype = "dynamic-tcpip";
1.137 markus 1479: } else {
1.336 millert 1480: nextstate = SSH_CHANNEL_OPENING;
1481: rtype = "direct-tcpip";
1.137 markus 1482: }
1.103 markus 1483:
1.41 markus 1484: addrlen = sizeof(addr);
1.285 djm 1485: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1486: if (newsock < 0) {
1.320 markus 1487: if (errno != EINTR && errno != EWOULDBLOCK &&
1488: errno != ECONNABORTED)
1489: error("accept: %.100s", strerror(errno));
1.317 djm 1490: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1491: c->notbefore = monotime() + 1;
1.41 markus 1492: return;
1493: }
1.336 millert 1494: if (c->host_port != PORT_STREAMLOCAL)
1495: set_nodelay(newsock);
1.190 markus 1496: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1497: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1498: nc->listening_port = c->listening_port;
1499: nc->host_port = c->host_port;
1.293 djm 1500: if (c->path != NULL)
1501: nc->path = xstrdup(c->path);
1.103 markus 1502:
1.299 markus 1503: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1504: port_open_helper(nc, rtype);
1.41 markus 1505: }
1506: }
1.25 markus 1507:
1.41 markus 1508: /*
1509: * This is the authentication agent socket listening for connections from
1510: * clients.
1511: */
1.259 stevesk 1512: /* ARGSUSED */
1.127 itojun 1513: static void
1.237 deraadt 1514: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1515: {
1.113 markus 1516: Channel *nc;
1517: int newsock;
1.285 djm 1518: struct sockaddr_storage addr;
1.41 markus 1519: socklen_t addrlen;
1.25 markus 1520:
1.41 markus 1521: if (FD_ISSET(c->sock, readset)) {
1522: addrlen = sizeof(addr);
1.285 djm 1523: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1524: if (newsock < 0) {
1.317 djm 1525: error("accept from auth socket: %.100s",
1526: strerror(errno));
1527: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1528: c->notbefore = monotime() + 1;
1.41 markus 1529: return;
1530: }
1.113 markus 1531: nc = channel_new("accepted auth socket",
1.73 markus 1532: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1533: c->local_window_max, c->local_maxpacket,
1.190 markus 1534: 0, "accepted auth socket", 1);
1.358 djm 1535: packet_start(SSH2_MSG_CHANNEL_OPEN);
1536: packet_put_cstring("auth-agent@openssh.com");
1537: packet_put_int(nc->self);
1538: packet_put_int(c->local_window_max);
1539: packet_put_int(c->local_maxpacket);
1.41 markus 1540: packet_send();
1541: }
1542: }
1.25 markus 1543:
1.259 stevesk 1544: /* ARGSUSED */
1.127 itojun 1545: static void
1.237 deraadt 1546: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1547: {
1.276 djm 1548: int err = 0, sock;
1.129 stevesk 1549: socklen_t sz = sizeof(err);
1.114 markus 1550:
1.75 markus 1551: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1552: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1553: err = errno;
1554: error("getsockopt SO_ERROR failed");
1555: }
1556: if (err == 0) {
1.276 djm 1557: debug("channel %d: connected to %s port %d",
1558: c->self, c->connect_ctx.host, c->connect_ctx.port);
1559: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1560: c->type = SSH_CHANNEL_OPEN;
1.358 djm 1561: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1562: packet_put_int(c->remote_id);
1563: packet_put_int(c->self);
1564: packet_put_int(c->local_window);
1565: packet_put_int(c->local_maxpacket);
1.75 markus 1566: } else {
1.276 djm 1567: debug("channel %d: connection failed: %s",
1.114 markus 1568: c->self, strerror(err));
1.276 djm 1569: /* Try next address, if any */
1570: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1571: close(c->sock);
1572: c->sock = c->rfd = c->wfd = sock;
1573: channel_max_fd = channel_find_maxfd();
1574: return;
1575: }
1576: /* Exhausted all addresses */
1577: error("connect_to %.100s port %d: failed.",
1578: c->connect_ctx.host, c->connect_ctx.port);
1579: channel_connect_ctx_free(&c->connect_ctx);
1.358 djm 1580: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1581: packet_put_int(c->remote_id);
1582: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1583: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1584: packet_put_cstring(strerror(err));
1585: packet_put_cstring("");
1.75 markus 1586: }
1.114 markus 1587: chan_mark_dead(c);
1.75 markus 1588: }
1.114 markus 1589: packet_send();
1.75 markus 1590: }
1591: }
1592:
1.259 stevesk 1593: /* ARGSUSED */
1.127 itojun 1594: static int
1.237 deraadt 1595: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1596: {
1.214 markus 1597: char buf[CHAN_RBUF];
1.41 markus 1598: int len;
1.25 markus 1599:
1.118 markus 1600: if (c->rfd != -1 &&
1.41 markus 1601: FD_ISSET(c->rfd, readset)) {
1602: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1603: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1604: return 1;
1.41 markus 1605: if (len <= 0) {
1.194 markus 1606: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1607: c->self, c->rfd, len);
1.104 markus 1608: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1609: debug2("channel %d: not open", c->self);
1.113 markus 1610: chan_mark_dead(c);
1.103 markus 1611: return -1;
1.25 markus 1612: } else {
1.41 markus 1613: chan_read_failed(c);
1.25 markus 1614: }
1.41 markus 1615: return -1;
1616: }
1.143 deraadt 1617: if (c->input_filter != NULL) {
1.66 markus 1618: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1619: debug2("channel %d: filter stops", c->self);
1.65 markus 1620: chan_read_failed(c);
1621: }
1.228 reyk 1622: } else if (c->datagram) {
1623: buffer_put_string(&c->input, buf, len);
1.65 markus 1624: } else {
1625: buffer_append(&c->input, buf, len);
1626: }
1.41 markus 1627: }
1628: return 1;
1629: }
1.241 deraadt 1630:
1.259 stevesk 1631: /* ARGSUSED */
1.127 itojun 1632: static int
1.237 deraadt 1633: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1634: {
1.95 markus 1635: struct termios tio;
1.231 reyk 1636: u_char *data = NULL, *buf;
1.309 djm 1637: u_int dlen, olen = 0;
1.41 markus 1638: int len;
1.25 markus 1639:
1.41 markus 1640: /* Send buffered output data to the socket. */
1.118 markus 1641: if (c->wfd != -1 &&
1.41 markus 1642: FD_ISSET(c->wfd, writeset) &&
1643: buffer_len(&c->output) > 0) {
1.309 djm 1644: olen = buffer_len(&c->output);
1.231 reyk 1645: if (c->output_filter != NULL) {
1646: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1647: debug2("channel %d: filter stops", c->self);
1.232 reyk 1648: if (c->type != SSH_CHANNEL_OPEN)
1649: chan_mark_dead(c);
1650: else
1651: chan_write_failed(c);
1652: return -1;
1.231 reyk 1653: }
1654: } else if (c->datagram) {
1655: buf = data = buffer_get_string(&c->output, &dlen);
1656: } else {
1657: buf = data = buffer_ptr(&c->output);
1658: dlen = buffer_len(&c->output);
1659: }
1660:
1.228 reyk 1661: if (c->datagram) {
1662: /* ignore truncated writes, datagrams might get lost */
1.231 reyk 1663: len = write(c->wfd, buf, dlen);
1.321 djm 1664: free(data);
1.228 reyk 1665: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1666: return 1;
1667: if (len <= 0) {
1668: if (c->type != SSH_CHANNEL_OPEN)
1669: chan_mark_dead(c);
1670: else
1671: chan_write_failed(c);
1672: return -1;
1673: }
1.309 djm 1674: goto out;
1.228 reyk 1675: }
1.231 reyk 1676:
1677: len = write(c->wfd, buf, dlen);
1.53 markus 1678: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1679: return 1;
1.41 markus 1680: if (len <= 0) {
1.104 markus 1681: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1682: debug2("channel %d: not open", c->self);
1.113 markus 1683: chan_mark_dead(c);
1.104 markus 1684: return -1;
1.41 markus 1685: } else {
1686: chan_write_failed(c);
1687: }
1688: return -1;
1.91 markus 1689: }
1.358 djm 1690: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1691: if (tcgetattr(c->wfd, &tio) == 0 &&
1692: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1693: /*
1694: * Simulate echo to reduce the impact of
1.96 markus 1695: * traffic analysis. We need to match the
1.95 markus 1696: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1697: * (4 byte channel id + buf)
1.91 markus 1698: */
1.95 markus 1699: packet_send_ignore(4 + len);
1.91 markus 1700: packet_send();
1701: }
1.25 markus 1702: }
1.41 markus 1703: buffer_consume(&c->output, len);
1.44 markus 1704: }
1.309 djm 1705: out:
1.358 djm 1706: if (olen > 0)
1.309 djm 1707: c->local_consumed += olen - buffer_len(&c->output);
1.44 markus 1708: return 1;
1709: }
1.241 deraadt 1710:
1.127 itojun 1711: static int
1.237 deraadt 1712: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1713: {
1.214 markus 1714: char buf[CHAN_RBUF];
1.44 markus 1715: int len;
1716:
1.45 markus 1717: /** XXX handle drain efd, too */
1.44 markus 1718: if (c->efd != -1) {
1719: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1720: FD_ISSET(c->efd, writeset) &&
1721: buffer_len(&c->extended) > 0) {
1722: len = write(c->efd, buffer_ptr(&c->extended),
1723: buffer_len(&c->extended));
1.70 markus 1724: debug2("channel %d: written %d to efd %d",
1.44 markus 1725: c->self, len, c->efd);
1.93 markus 1726: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1727: return 1;
1728: if (len <= 0) {
1729: debug2("channel %d: closing write-efd %d",
1730: c->self, c->efd);
1.132 markus 1731: channel_close_fd(&c->efd);
1.93 markus 1732: } else {
1.44 markus 1733: buffer_consume(&c->extended, len);
1734: c->local_consumed += len;
1735: }
1.306 djm 1736: } else if (c->efd != -1 &&
1737: (c->extended_usage == CHAN_EXTENDED_READ ||
1738: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 1739: FD_ISSET(c->efd, readset)) {
1740: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1741: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1742: c->self, len, c->efd);
1.93 markus 1743: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1744: return 1;
1745: if (len <= 0) {
1746: debug2("channel %d: closing read-efd %d",
1.45 markus 1747: c->self, c->efd);
1.132 markus 1748: channel_close_fd(&c->efd);
1.93 markus 1749: } else {
1.306 djm 1750: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
1751: debug3("channel %d: discard efd",
1752: c->self);
1753: } else
1754: buffer_append(&c->extended, buf, len);
1.93 markus 1755: }
1.44 markus 1756: }
1757: }
1758: return 1;
1759: }
1.241 deraadt 1760:
1.259 stevesk 1761: /* ARGSUSED */
1.127 itojun 1762: static int
1.93 markus 1763: channel_check_window(Channel *c)
1.44 markus 1764: {
1.104 markus 1765: if (c->type == SSH_CHANNEL_OPEN &&
1766: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1767: ((c->local_window_max - c->local_window >
1.269 markus 1768: c->local_maxpacket*3) ||
1769: c->local_window < c->local_window_max/2) &&
1.44 markus 1770: c->local_consumed > 0) {
1771: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1772: packet_put_int(c->remote_id);
1773: packet_put_int(c->local_consumed);
1774: packet_send();
1.70 markus 1775: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1776: c->self, c->local_window,
1777: c->local_consumed);
1778: c->local_window += c->local_consumed;
1779: c->local_consumed = 0;
1.1 deraadt 1780: }
1.41 markus 1781: return 1;
1.1 deraadt 1782: }
1783:
1.127 itojun 1784: static void
1.237 deraadt 1785: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1786: {
1787: channel_handle_rfd(c, readset, writeset);
1788: channel_handle_wfd(c, readset, writeset);
1.44 markus 1789: channel_handle_efd(c, readset, writeset);
1.93 markus 1790: channel_check_window(c);
1.44 markus 1791: }
1792:
1.302 djm 1793: static u_int
1794: read_mux(Channel *c, u_int need)
1795: {
1796: char buf[CHAN_RBUF];
1797: int len;
1798: u_int rlen;
1799:
1800: if (buffer_len(&c->input) < need) {
1801: rlen = need - buffer_len(&c->input);
1.352 deraadt 1802: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 1803: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1804: return buffer_len(&c->input);
1.302 djm 1805: if (len <= 0) {
1.349 naddy 1806: debug2("channel %d: ctl read<=0 rfd %d len %d",
1807: c->self, c->rfd, len);
1808: chan_read_failed(c);
1809: return 0;
1.302 djm 1810: } else
1811: buffer_append(&c->input, buf, len);
1812: }
1813: return buffer_len(&c->input);
1814: }
1815:
1816: static void
1817: channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1818: {
1819: u_int need;
1820: ssize_t len;
1821:
1.304 djm 1822: if (c->rfd != -1 && !c->mux_pause && FD_ISSET(c->rfd, readset) &&
1.302 djm 1823: (c->istate == CHAN_INPUT_OPEN ||
1824: c->istate == CHAN_INPUT_WAIT_DRAIN)) {
1825: /*
1826: * Don't not read past the precise end of packets to
1827: * avoid disrupting fd passing.
1828: */
1829: if (read_mux(c, 4) < 4) /* read header */
1830: return;
1831: need = get_u32(buffer_ptr(&c->input));
1832: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1833: if (need > CHANNEL_MUX_MAX_PACKET) {
1834: debug2("channel %d: packet too big %u > %u",
1835: c->self, CHANNEL_MUX_MAX_PACKET, need);
1836: chan_rcvd_oclose(c);
1837: return;
1838: }
1839: if (read_mux(c, need + 4) < need + 4) /* read body */
1840: return;
1841: if (c->mux_rcb(c) != 0) {
1842: debug("channel %d: mux_rcb failed", c->self);
1843: chan_mark_dead(c);
1844: return;
1845: }
1846: }
1847:
1848: if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) &&
1849: buffer_len(&c->output) > 0) {
1850: len = write(c->wfd, buffer_ptr(&c->output),
1851: buffer_len(&c->output));
1852: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1853: return;
1854: if (len <= 0) {
1855: chan_mark_dead(c);
1856: return;
1857: }
1858: buffer_consume(&c->output, len);
1859: }
1860: }
1861:
1862: static void
1863: channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset)
1864: {
1865: Channel *nc;
1866: struct sockaddr_storage addr;
1867: socklen_t addrlen;
1868: int newsock;
1869: uid_t euid;
1870: gid_t egid;
1871:
1872: if (!FD_ISSET(c->sock, readset))
1873: return;
1874:
1875: debug("multiplexing control connection");
1876:
1877: /*
1878: * Accept connection on control socket
1879: */
1880: memset(&addr, 0, sizeof(addr));
1881: addrlen = sizeof(addr);
1882: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
1883: &addrlen)) == -1) {
1884: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 1885: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1886: c->notbefore = monotime() + 1;
1.302 djm 1887: return;
1888: }
1889:
1890: if (getpeereid(newsock, &euid, &egid) < 0) {
1891: error("%s getpeereid failed: %s", __func__,
1892: strerror(errno));
1893: close(newsock);
1894: return;
1895: }
1896: if ((euid != 0) && (getuid() != euid)) {
1897: error("multiplex uid mismatch: peer euid %u != uid %u",
1898: (u_int)euid, (u_int)getuid());
1899: close(newsock);
1900: return;
1901: }
1902: nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT,
1903: newsock, newsock, -1, c->local_window_max,
1904: c->local_maxpacket, 0, "mux-control", 1);
1905: nc->mux_rcb = c->mux_rcb;
1906: debug3("%s: new mux channel %d fd %d", __func__,
1907: nc->self, nc->sock);
1908: /* establish state */
1909: nc->mux_rcb(nc);
1910: /* mux state transitions must not elicit protocol messages */
1911: nc->flags |= CHAN_LOCAL;
1912: }
1913:
1.127 itojun 1914: static void
1.358 djm 1915: channel_handler_init(void)
1.1 deraadt 1916: {
1.358 djm 1917: int i;
1.180 deraadt 1918:
1.358 djm 1919: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1920: channel_pre[i] = NULL;
1921: channel_post[i] = NULL;
1.41 markus 1922: }
1.157 markus 1923: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1924: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1925: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1926: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.336 millert 1927: channel_pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
1928: channel_pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
1.51 markus 1929: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1930: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1931: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1932: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.302 djm 1933: channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
1934: channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
1.44 markus 1935:
1.157 markus 1936: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1937: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1938: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.336 millert 1939: channel_post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
1940: channel_post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
1.51 markus 1941: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1942: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1943: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1944: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.302 djm 1945: channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
1946: channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.44 markus 1947: }
1948:
1.140 markus 1949: /* gc dead channels */
1950: static void
1951: channel_garbage_collect(Channel *c)
1952: {
1953: if (c == NULL)
1954: return;
1955: if (c->detach_user != NULL) {
1.225 djm 1956: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1957: return;
1.194 markus 1958: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1959: c->detach_user(c->self, NULL);
1960: /* if we still have a callback */
1961: if (c->detach_user != NULL)
1962: return;
1.194 markus 1963: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1964: }
1965: if (!chan_is_dead(c, 1))
1966: return;
1.194 markus 1967: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1968: channel_free(c);
1969: }
1970:
1.127 itojun 1971: static void
1.317 djm 1972: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset,
1973: time_t *unpause_secs)
1.41 markus 1974: {
1975: static int did_init = 0;
1.299 markus 1976: u_int i, oalloc;
1.41 markus 1977: Channel *c;
1.317 djm 1978: time_t now;
1.25 markus 1979:
1.41 markus 1980: if (!did_init) {
1981: channel_handler_init();
1982: did_init = 1;
1983: }
1.322 dtucker 1984: now = monotime();
1.317 djm 1985: if (unpause_secs != NULL)
1986: *unpause_secs = 0;
1.299 markus 1987: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 1988: c = channels[i];
1989: if (c == NULL)
1.41 markus 1990: continue;
1.299 markus 1991: if (c->delayed) {
1992: if (ftab == channel_pre)
1993: c->delayed = 0;
1994: else
1995: continue;
1996: }
1.317 djm 1997: if (ftab[c->type] != NULL) {
1998: /*
1999: * Run handlers that are not paused.
2000: */
2001: if (c->notbefore <= now)
2002: (*ftab[c->type])(c, readset, writeset);
2003: else if (unpause_secs != NULL) {
2004: /*
2005: * Collect the time that the earliest
2006: * channel comes off pause.
2007: */
2008: debug3("%s: chan %d: skip for %d more seconds",
2009: __func__, c->self,
2010: (int)(c->notbefore - now));
2011: if (*unpause_secs == 0 ||
2012: (c->notbefore - now) < *unpause_secs)
2013: *unpause_secs = c->notbefore - now;
2014: }
2015: }
1.140 markus 2016: channel_garbage_collect(c);
1.1 deraadt 2017: }
1.317 djm 2018: if (unpause_secs != NULL && *unpause_secs != 0)
2019: debug3("%s: first channel unpauses in %d seconds",
2020: __func__, (int)*unpause_secs);
1.1 deraadt 2021: }
2022:
1.121 markus 2023: /*
2024: * Allocate/update select bitmasks and add any bits relevant to channels in
2025: * select bitmasks.
2026: */
1.49 markus 2027: void
1.100 markus 2028: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.318 djm 2029: u_int *nallocp, time_t *minwait_secs, int rekeying)
1.41 markus 2030: {
1.243 djm 2031: u_int n, sz, nfdset;
1.84 markus 2032:
1.352 deraadt 2033: n = MAXIMUM(*maxfdp, channel_max_fd);
1.84 markus 2034:
1.243 djm 2035: nfdset = howmany(n+1, NFDBITS);
2036: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2037: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2038: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2039: sz = nfdset * sizeof(fd_mask);
2040:
1.132 markus 2041: /* perhaps check sz < nalloc/2 and shrink? */
2042: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2043: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2044: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2045: *nallocp = sz;
1.84 markus 2046: }
1.132 markus 2047: *maxfdp = n;
1.84 markus 2048: memset(*readsetp, 0, sz);
2049: memset(*writesetp, 0, sz);
2050:
1.100 markus 2051: if (!rekeying)
1.317 djm 2052: channel_handler(channel_pre, *readsetp, *writesetp,
2053: minwait_secs);
1.41 markus 2054: }
2055:
1.121 markus 2056: /*
2057: * After select, perform any appropriate operations for channels which have
2058: * events pending.
2059: */
1.49 markus 2060: void
1.237 deraadt 2061: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 2062: {
1.317 djm 2063: channel_handler(channel_post, readset, writeset, NULL);
1.41 markus 2064: }
2065:
1.121 markus 2066:
1.84 markus 2067: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2068: void
1.142 itojun 2069: channel_output_poll(void)
1.1 deraadt 2070: {
1.41 markus 2071: Channel *c;
1.209 avsm 2072: u_int i, len;
1.1 deraadt 2073:
1.25 markus 2074: for (i = 0; i < channels_alloc; i++) {
1.113 markus 2075: c = channels[i];
2076: if (c == NULL)
2077: continue;
1.37 markus 2078:
1.121 markus 2079: /*
2080: * We are only interested in channels that can have buffered
2081: * incoming data.
2082: */
1.358 djm 2083: if (c->type != SSH_CHANNEL_OPEN)
2084: continue;
2085: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2086: /* XXX is this true? */
1.140 markus 2087: debug3("channel %d: will not send data after close", c->self);
1.44 markus 2088: continue;
2089: }
1.25 markus 2090:
2091: /* Get the amount of buffered data for this channel. */
1.93 markus 2092: if ((c->istate == CHAN_INPUT_OPEN ||
2093: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2094: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 2095: if (c->datagram) {
2096: if (len > 0) {
2097: u_char *data;
2098: u_int dlen;
2099:
2100: data = buffer_get_string(&c->input,
2101: &dlen);
1.309 djm 2102: if (dlen > c->remote_window ||
2103: dlen > c->remote_maxpacket) {
2104: debug("channel %d: datagram "
2105: "too big for channel",
2106: c->self);
1.321 djm 2107: free(data);
1.309 djm 2108: continue;
2109: }
1.228 reyk 2110: packet_start(SSH2_MSG_CHANNEL_DATA);
2111: packet_put_int(c->remote_id);
2112: packet_put_string(data, dlen);
2113: packet_send();
1.345 djm 2114: c->remote_window -= dlen;
1.321 djm 2115: free(data);
1.228 reyk 2116: }
2117: continue;
2118: }
1.121 markus 2119: /*
2120: * Send some data for the other side over the secure
2121: * connection.
2122: */
1.358 djm 2123: if (len > c->remote_window)
2124: len = c->remote_window;
2125: if (len > c->remote_maxpacket)
2126: len = c->remote_maxpacket;
1.41 markus 2127: if (len > 0) {
1.358 djm 2128: packet_start(SSH2_MSG_CHANNEL_DATA);
1.41 markus 2129: packet_put_int(c->remote_id);
2130: packet_put_string(buffer_ptr(&c->input), len);
2131: packet_send();
2132: buffer_consume(&c->input, len);
2133: c->remote_window -= len;
2134: }
2135: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.27 markus 2136: /*
2137: * input-buffer is empty and read-socket shutdown:
1.172 markus 2138: * tell peer, that we will not send more data: send IEOF.
2139: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2140: */
1.172 markus 2141: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2142: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2143: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2144: else
2145: chan_ibuf_empty(c);
1.25 markus 2146: }
1.44 markus 2147: /* Send extended data, i.e. stderr */
1.358 djm 2148: if (!(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2149: c->remote_window > 0 &&
2150: (len = buffer_len(&c->extended)) > 0 &&
2151: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2152: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2153: c->self, c->remote_window, buffer_len(&c->extended),
2154: c->extended_usage);
1.44 markus 2155: if (len > c->remote_window)
2156: len = c->remote_window;
2157: if (len > c->remote_maxpacket)
2158: len = c->remote_maxpacket;
2159: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2160: packet_put_int(c->remote_id);
2161: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2162: packet_put_string(buffer_ptr(&c->extended), len);
2163: packet_send();
2164: buffer_consume(&c->extended, len);
2165: c->remote_window -= len;
1.93 markus 2166: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2167: }
1.25 markus 2168: }
1.1 deraadt 2169: }
2170:
1.354 markus 2171: /* -- mux proxy support */
2172:
2173: /*
2174: * When multiplexing channel messages for mux clients we have to deal
2175: * with downstream messages from the mux client and upstream messages
2176: * from the ssh server:
2177: * 1) Handling downstream messages is straightforward and happens
2178: * in channel_proxy_downstream():
2179: * - We forward all messages (mostly) unmodified to the server.
2180: * - However, in order to route messages from upstream to the correct
2181: * downstream client, we have to replace the channel IDs used by the
2182: * mux clients with a unique channel ID because the mux clients might
2183: * use conflicting channel IDs.
2184: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2185: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2186: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2187: * with the newly allocated channel ID.
2188: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
2189: * channels and procesed by channel_proxy_upstream(). The local channel ID
2190: * is then translated back to the original mux client ID.
2191: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2192: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2193: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2194: * downstream mux client are removed.
2195: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2196: * requires more work, because they are not addressed to a specific
2197: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2198: * out whether the request is addressed to the local client or a
2199: * specific downstream client based on the listen-address/port.
2200: * 6) Agent and X11-Forwarding have a similar problem and are currenly
2201: * not supported as the matching session/channel cannot be identified
2202: * easily.
2203: */
2204:
2205: /*
2206: * receive packets from downstream mux clients:
2207: * channel callback fired on read from mux client, creates
2208: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2209: * on channel creation.
2210: */
2211: int
2212: channel_proxy_downstream(Channel *downstream)
2213: {
2214: Channel *c = NULL;
2215: struct ssh *ssh = active_state;
2216: struct sshbuf *original = NULL, *modified = NULL;
2217: const u_char *cp;
2218: char *ctype = NULL, *listen_host = NULL;
2219: u_char type;
2220: size_t have;
1.355 djm 2221: int ret = -1, r, idx;
2222: u_int id, remote_id, listen_port;
1.354 markus 2223:
2224: /* sshbuf_dump(&downstream->input, stderr); */
2225: if ((r = sshbuf_get_string_direct(&downstream->input, &cp, &have))
2226: != 0) {
2227: error("%s: malformed message: %s", __func__, ssh_err(r));
2228: return -1;
2229: }
2230: if (have < 2) {
2231: error("%s: short message", __func__);
2232: return -1;
2233: }
2234: type = cp[1];
2235: /* skip padlen + type */
2236: cp += 2;
2237: have -= 2;
2238: if (ssh_packet_log_type(type))
2239: debug3("%s: channel %u: down->up: type %u", __func__,
2240: downstream->self, type);
2241:
2242: switch (type) {
2243: case SSH2_MSG_CHANNEL_OPEN:
2244: if ((original = sshbuf_from(cp, have)) == NULL ||
2245: (modified = sshbuf_new()) == NULL) {
2246: error("%s: alloc", __func__);
2247: goto out;
2248: }
2249: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2250: (r = sshbuf_get_u32(original, &id)) != 0) {
2251: error("%s: parse error %s", __func__, ssh_err(r));
2252: goto out;
2253: }
2254: c = channel_new("mux proxy", SSH_CHANNEL_MUX_PROXY,
2255: -1, -1, -1, 0, 0, 0, ctype, 1);
2256: c->mux_ctx = downstream; /* point to mux client */
2257: c->mux_downstream_id = id; /* original downstream id */
2258: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2259: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2260: (r = sshbuf_putb(modified, original)) != 0) {
2261: error("%s: compose error %s", __func__, ssh_err(r));
2262: channel_free(c);
2263: goto out;
2264: }
2265: break;
2266: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2267: /*
2268: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2269: * need to parse 'remote_id' instead of 'ctype'.
2270: */
2271: if ((original = sshbuf_from(cp, have)) == NULL ||
2272: (modified = sshbuf_new()) == NULL) {
2273: error("%s: alloc", __func__);
2274: goto out;
2275: }
2276: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2277: (r = sshbuf_get_u32(original, &id)) != 0) {
2278: error("%s: parse error %s", __func__, ssh_err(r));
2279: goto out;
2280: }
2281: c = channel_new("mux proxy", SSH_CHANNEL_MUX_PROXY,
2282: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2283: c->mux_ctx = downstream; /* point to mux client */
2284: c->mux_downstream_id = id;
2285: c->remote_id = remote_id;
2286: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2287: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2288: (r = sshbuf_putb(modified, original)) != 0) {
2289: error("%s: compose error %s", __func__, ssh_err(r));
2290: channel_free(c);
2291: goto out;
2292: }
2293: break;
2294: case SSH2_MSG_GLOBAL_REQUEST:
2295: if ((original = sshbuf_from(cp, have)) == NULL) {
2296: error("%s: alloc", __func__);
2297: goto out;
2298: }
2299: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2300: error("%s: parse error %s", __func__, ssh_err(r));
2301: goto out;
2302: }
2303: if (strcmp(ctype, "tcpip-forward") != 0) {
2304: error("%s: unsupported request %s", __func__, ctype);
2305: goto out;
2306: }
2307: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2308: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2309: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2310: error("%s: parse error %s", __func__, ssh_err(r));
2311: goto out;
2312: }
1.355 djm 2313: if (listen_port > 65535) {
2314: error("%s: tcpip-forward for %s: bad port %u",
2315: __func__, listen_host, listen_port);
2316: goto out;
2317: }
1.354 markus 2318: /* Record that connection to this host/port is permitted. */
2319: permitted_opens = xreallocarray(permitted_opens,
2320: num_permitted_opens + 1, sizeof(*permitted_opens));
2321: idx = num_permitted_opens++;
2322: permitted_opens[idx].host_to_connect = xstrdup("<mux>");
2323: permitted_opens[idx].port_to_connect = -1;
2324: permitted_opens[idx].listen_host = listen_host;
1.355 djm 2325: permitted_opens[idx].listen_port = (int)listen_port;
1.354 markus 2326: permitted_opens[idx].downstream = downstream;
2327: listen_host = NULL;
2328: break;
2329: case SSH2_MSG_CHANNEL_CLOSE:
2330: if (have < 4)
2331: break;
2332: remote_id = PEEK_U32(cp);
2333: if ((c = channel_by_remote_id(remote_id)) != NULL) {
2334: if (c->flags & CHAN_CLOSE_RCVD)
2335: channel_free(c);
2336: else
2337: c->flags |= CHAN_CLOSE_SENT;
2338: }
2339: break;
2340: }
2341: if (modified) {
2342: if ((r = sshpkt_start(ssh, type)) != 0 ||
2343: (r = sshpkt_putb(ssh, modified)) != 0 ||
2344: (r = sshpkt_send(ssh)) != 0) {
2345: error("%s: send %s", __func__, ssh_err(r));
2346: goto out;
2347: }
2348: } else {
2349: if ((r = sshpkt_start(ssh, type)) != 0 ||
2350: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2351: (r = sshpkt_send(ssh)) != 0) {
2352: error("%s: send %s", __func__, ssh_err(r));
2353: goto out;
2354: }
2355: }
2356: ret = 0;
2357: out:
2358: free(ctype);
2359: free(listen_host);
2360: sshbuf_free(original);
2361: sshbuf_free(modified);
2362: return ret;
2363: }
2364:
2365: /*
2366: * receive packets from upstream server and de-multiplex packets
2367: * to correct downstream:
2368: * implemented as a helper for channel input handlers,
2369: * replaces local (proxy) channel ID with downstream channel ID.
2370: */
2371: int
1.363 markus 2372: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2373: {
2374: struct sshbuf *b = NULL;
2375: Channel *downstream;
2376: const u_char *cp = NULL;
2377: size_t len;
2378: int r;
2379:
2380: /*
2381: * When receiving packets from the peer we need to check whether we
2382: * need to forward the packets to the mux client. In this case we
2383: * restore the orignal channel id and keep track of CLOSE messages,
2384: * so we can cleanup the channel.
2385: */
2386: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2387: return 0;
2388: if ((downstream = c->mux_ctx) == NULL)
2389: return 0;
2390: switch (type) {
2391: case SSH2_MSG_CHANNEL_CLOSE:
2392: case SSH2_MSG_CHANNEL_DATA:
2393: case SSH2_MSG_CHANNEL_EOF:
2394: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2395: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2396: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2397: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2398: case SSH2_MSG_CHANNEL_SUCCESS:
2399: case SSH2_MSG_CHANNEL_FAILURE:
2400: case SSH2_MSG_CHANNEL_REQUEST:
2401: break;
2402: default:
2403: debug2("%s: channel %u: unsupported type %u", __func__,
2404: c->self, type);
2405: return 0;
2406: }
2407: if ((b = sshbuf_new()) == NULL) {
2408: error("%s: alloc reply", __func__);
2409: goto out;
2410: }
2411: /* get remaining payload (after id) */
2412: cp = sshpkt_ptr(ssh, &len);
2413: if (cp == NULL) {
2414: error("%s: no packet", __func__);
2415: goto out;
2416: }
2417: /* translate id and send to muxclient */
2418: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2419: (r = sshbuf_put_u8(b, type)) != 0 ||
2420: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2421: (r = sshbuf_put(b, cp, len)) != 0 ||
2422: (r = sshbuf_put_stringb(&downstream->output, b)) != 0) {
2423: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2424: goto out;
2425: }
2426: /* sshbuf_dump(b, stderr); */
2427: if (ssh_packet_log_type(type))
2428: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2429: type);
2430: out:
2431: /* update state */
2432: switch (type) {
2433: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2434: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
2435: if (cp && len > 4)
2436: c->remote_id = PEEK_U32(cp);
2437: break;
2438: case SSH2_MSG_CHANNEL_CLOSE:
2439: if (c->flags & CHAN_CLOSE_SENT)
2440: channel_free(c);
2441: else
2442: c->flags |= CHAN_CLOSE_RCVD;
2443: break;
2444: }
2445: sshbuf_free(b);
2446: return 1;
2447: }
1.121 markus 2448:
2449: /* -- protocol input */
1.249 djm 2450:
2451: /* ARGSUSED */
1.339 markus 2452: int
1.363 markus 2453: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2454: {
1.37 markus 2455: int id;
1.332 djm 2456: const u_char *data;
1.309 djm 2457: u_int data_len, win_len;
1.41 markus 2458: Channel *c;
1.25 markus 2459:
2460: /* Get the channel number and verify it. */
1.37 markus 2461: id = packet_get_int();
1.41 markus 2462: c = channel_lookup(id);
2463: if (c == NULL)
1.37 markus 2464: packet_disconnect("Received data for nonexistent channel %d.", id);
1.363 markus 2465: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2466: return 0;
1.25 markus 2467:
2468: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2469: if (c->type != SSH_CHANNEL_OPEN &&
2470: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2471: return 0;
1.37 markus 2472:
1.25 markus 2473: /* Get the data. */
1.274 markus 2474: data = packet_get_string_ptr(&data_len);
1.309 djm 2475: win_len = data_len;
2476: if (c->datagram)
2477: win_len += 4; /* string length header */
1.200 markus 2478:
2479: /*
2480: * Ignore data for protocol > 1.3 if output end is no longer open.
2481: * For protocol 2 the sending side is reducing its window as it sends
2482: * data, so we must 'fake' consumption of the data in order to ensure
2483: * that window updates are sent back. Otherwise the connection might
2484: * deadlock.
2485: */
1.358 djm 2486: if (c->ostate != CHAN_OUTPUT_OPEN) {
2487: c->local_window -= win_len;
2488: c->local_consumed += win_len;
1.339 markus 2489: return 0;
1.200 markus 2490: }
1.41 markus 2491:
1.358 djm 2492: if (win_len > c->local_maxpacket) {
2493: logit("channel %d: rcvd big packet %d, maxpack %d",
2494: c->self, win_len, c->local_maxpacket);
2495: }
2496: if (win_len > c->local_window) {
2497: logit("channel %d: rcvd too much data %d, win %d",
2498: c->self, win_len, c->local_window);
2499: return 0;
1.44 markus 2500: }
1.358 djm 2501: c->local_window -= win_len;
2502:
1.228 reyk 2503: if (c->datagram)
2504: buffer_put_string(&c->output, data, data_len);
2505: else
2506: buffer_append(&c->output, data, data_len);
1.274 markus 2507: packet_check_eom();
1.339 markus 2508: return 0;
1.1 deraadt 2509: }
1.121 markus 2510:
1.249 djm 2511: /* ARGSUSED */
1.339 markus 2512: int
1.363 markus 2513: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 2514: {
2515: int id;
2516: char *data;
1.177 markus 2517: u_int data_len, tcode;
1.44 markus 2518: Channel *c;
2519:
2520: /* Get the channel number and verify it. */
2521: id = packet_get_int();
2522: c = channel_lookup(id);
2523:
2524: if (c == NULL)
2525: packet_disconnect("Received extended_data for bad channel %d.", id);
1.363 markus 2526: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2527: return 0;
1.44 markus 2528: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2529: logit("channel %d: ext data for non open", id);
1.339 markus 2530: return 0;
1.172 markus 2531: }
2532: if (c->flags & CHAN_EOF_RCVD) {
2533: if (datafellows & SSH_BUG_EXTEOF)
2534: debug("channel %d: accepting ext data after eof", id);
2535: else
2536: packet_disconnect("Received extended_data after EOF "
2537: "on channel %d.", id);
1.44 markus 2538: }
2539: tcode = packet_get_int();
2540: if (c->efd == -1 ||
2541: c->extended_usage != CHAN_EXTENDED_WRITE ||
2542: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2543: logit("channel %d: bad ext data", c->self);
1.339 markus 2544: return 0;
1.44 markus 2545: }
2546: data = packet_get_string(&data_len);
1.152 markus 2547: packet_check_eom();
1.44 markus 2548: if (data_len > c->local_window) {
1.188 itojun 2549: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2550: c->self, data_len, c->local_window);
1.321 djm 2551: free(data);
1.339 markus 2552: return 0;
1.44 markus 2553: }
1.70 markus 2554: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2555: c->local_window -= data_len;
2556: buffer_append(&c->extended, data, data_len);
1.321 djm 2557: free(data);
1.339 markus 2558: return 0;
1.44 markus 2559: }
2560:
1.249 djm 2561: /* ARGSUSED */
1.339 markus 2562: int
1.363 markus 2563: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 2564: {
2565: int id;
2566: Channel *c;
2567:
2568: id = packet_get_int();
1.152 markus 2569: packet_check_eom();
1.41 markus 2570: c = channel_lookup(id);
2571: if (c == NULL)
2572: packet_disconnect("Received ieof for nonexistent channel %d.", id);
1.363 markus 2573: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2574: return 0;
1.41 markus 2575: chan_rcvd_ieof(c);
1.133 markus 2576:
2577: /* XXX force input close */
1.156 markus 2578: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2579: debug("channel %d: FORCE input drain", c->self);
2580: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2581: if (buffer_len(&c->input) == 0)
2582: chan_ibuf_empty(c);
1.133 markus 2583: }
1.339 markus 2584: return 0;
1.41 markus 2585: }
1.1 deraadt 2586:
1.249 djm 2587: /* ARGSUSED */
1.339 markus 2588: int
1.363 markus 2589: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 2590: {
2591: int id = packet_get_int();
2592: Channel *c = channel_lookup(id);
1.151 markus 2593:
1.41 markus 2594: if (c == NULL)
2595: packet_disconnect("Received oclose for nonexistent channel %d.", id);
1.363 markus 2596: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2597: return 0;
2598: packet_check_eom();
1.41 markus 2599: chan_rcvd_oclose(c);
1.339 markus 2600: return 0;
1.1 deraadt 2601: }
2602:
1.249 djm 2603: /* ARGSUSED */
1.339 markus 2604: int
1.363 markus 2605: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2606: {
1.41 markus 2607: int id, remote_id;
2608: Channel *c;
1.1 deraadt 2609:
1.41 markus 2610: id = packet_get_int();
2611: c = channel_lookup(id);
1.25 markus 2612:
1.354 markus 2613: if (c==NULL)
2614: packet_disconnect("Received open confirmation for "
2615: "unknown channel %d.", id);
1.363 markus 2616: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2617: return 0;
2618: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 2619: packet_disconnect("Received open confirmation for "
2620: "non-opening channel %d.", id);
2621: remote_id = packet_get_int();
1.27 markus 2622: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2623: c->remote_id = remote_id;
2624: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2625:
1.358 djm 2626: c->remote_window = packet_get_int();
2627: c->remote_maxpacket = packet_get_int();
2628: if (c->open_confirm) {
2629: debug2("callback start");
2630: c->open_confirm(c->self, 1, c->open_confirm_ctx);
2631: debug2("callback done");
1.44 markus 2632: }
1.358 djm 2633: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
2634: c->remote_window, c->remote_maxpacket);
1.152 markus 2635: packet_check_eom();
1.339 markus 2636: return 0;
1.1 deraadt 2637: }
2638:
1.127 itojun 2639: static char *
1.114 markus 2640: reason2txt(int reason)
2641: {
1.143 deraadt 2642: switch (reason) {
1.114 markus 2643: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2644: return "administratively prohibited";
2645: case SSH2_OPEN_CONNECT_FAILED:
2646: return "connect failed";
2647: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2648: return "unknown channel type";
2649: case SSH2_OPEN_RESOURCE_SHORTAGE:
2650: return "resource shortage";
2651: }
1.117 stevesk 2652: return "unknown reason";
1.114 markus 2653: }
2654:
1.249 djm 2655: /* ARGSUSED */
1.339 markus 2656: int
1.363 markus 2657: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2658: {
1.86 markus 2659: int id, reason;
2660: char *msg = NULL, *lang = NULL;
1.41 markus 2661: Channel *c;
2662:
2663: id = packet_get_int();
2664: c = channel_lookup(id);
1.25 markus 2665:
1.354 markus 2666: if (c==NULL)
2667: packet_disconnect("Received open failure for "
2668: "unknown channel %d.", id);
1.363 markus 2669: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2670: return 0;
2671: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 2672: packet_disconnect("Received open failure for "
2673: "non-opening channel %d.", id);
1.358 djm 2674: reason = packet_get_int();
2675: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
2676: msg = packet_get_string(NULL);
2677: lang = packet_get_string(NULL);
2678: }
2679: logit("channel %d: open failed: %s%s%s", id,
2680: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
2681: free(msg);
2682: free(lang);
2683: if (c->open_confirm) {
2684: debug2("callback start");
2685: c->open_confirm(c->self, 0, c->open_confirm_ctx);
2686: debug2("callback done");
1.44 markus 2687: }
1.152 markus 2688: packet_check_eom();
1.291 djm 2689: /* Schedule the channel for cleanup/deletion. */
2690: chan_mark_dead(c);
1.339 markus 2691: return 0;
1.44 markus 2692: }
2693:
1.249 djm 2694: /* ARGSUSED */
1.339 markus 2695: int
1.363 markus 2696: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 2697: {
2698: Channel *c;
1.178 markus 2699: int id;
1.346 djm 2700: u_int adjust, tmp;
1.121 markus 2701:
2702: /* Get the channel number and verify it. */
2703: id = packet_get_int();
2704: c = channel_lookup(id);
1.1 deraadt 2705:
1.229 markus 2706: if (c == NULL) {
2707: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 2708: return 0;
1.121 markus 2709: }
1.363 markus 2710: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2711: return 0;
1.121 markus 2712: adjust = packet_get_int();
1.152 markus 2713: packet_check_eom();
1.178 markus 2714: debug2("channel %d: rcvd adjust %u", id, adjust);
1.346 djm 2715: if ((tmp = c->remote_window + adjust) < c->remote_window)
2716: fatal("channel %d: adjust %u overflows remote window %u",
2717: id, adjust, c->remote_window);
2718: c->remote_window = tmp;
1.339 markus 2719: return 0;
1.121 markus 2720: }
1.1 deraadt 2721:
1.249 djm 2722: /* ARGSUSED */
1.339 markus 2723: int
1.363 markus 2724: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 2725: {
2726: Channel *c;
2727: struct channel_confirm *cc;
1.289 markus 2728: int id;
1.275 djm 2729:
2730: /* Reset keepalive timeout */
1.296 andreas 2731: packet_set_alive_timeouts(0);
1.275 djm 2732:
1.289 markus 2733: id = packet_get_int();
2734: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2735:
1.289 markus 2736: if ((c = channel_lookup(id)) == NULL) {
2737: logit("channel_input_status_confirm: %d: unknown", id);
1.339 markus 2738: return 0;
1.275 djm 2739: }
1.363 markus 2740: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2741: return 0;
2742: packet_check_eom();
1.275 djm 2743: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 2744: return 0;
1.275 djm 2745: cc->cb(type, c, cc->ctx);
2746: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 2747: explicit_bzero(cc, sizeof(*cc));
1.321 djm 2748: free(cc);
1.339 markus 2749: return 0;
1.275 djm 2750: }
1.121 markus 2751:
2752: /* -- tcp forwarding */
1.135 markus 2753:
2754: void
2755: channel_set_af(int af)
2756: {
2757: IPv4or6 = af;
2758: }
1.121 markus 2759:
1.312 djm 2760:
2761: /*
2762: * Determine whether or not a port forward listens to loopback, the
2763: * specified address or wildcard. On the client, a specified bind
2764: * address will always override gateway_ports. On the server, a
2765: * gateway_ports of 1 (``yes'') will override the client's specification
2766: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
2767: * will bind to whatever address the client asked for.
2768: *
2769: * Special-case listen_addrs are:
2770: *
2771: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2772: * "" (empty string), "*" -> wildcard v4/v6
2773: * "localhost" -> loopback v4/v6
1.334 djm 2774: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 2775: */
2776: static const char *
2777: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 2778: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 2779: {
2780: const char *addr = NULL;
2781: int wildcard = 0;
2782:
2783: if (listen_addr == NULL) {
2784: /* No address specified: default to gateway_ports setting */
1.336 millert 2785: if (fwd_opts->gateway_ports)
1.312 djm 2786: wildcard = 1;
1.336 millert 2787: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 2788: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2789: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
2790: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 2791: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 2792: wildcard = 1;
1.326 djm 2793: /*
2794: * Notify client if they requested a specific listen
2795: * address and it was overridden.
2796: */
2797: if (*listen_addr != '\0' &&
2798: strcmp(listen_addr, "0.0.0.0") != 0 &&
2799: strcmp(listen_addr, "*") != 0) {
2800: packet_send_debug("Forwarding listen address "
2801: "\"%s\" overridden by server "
2802: "GatewayPorts", listen_addr);
2803: }
1.334 djm 2804: } else if (strcmp(listen_addr, "localhost") != 0 ||
2805: strcmp(listen_addr, "127.0.0.1") == 0 ||
2806: strcmp(listen_addr, "::1") == 0) {
2807: /* Accept localhost address when GatewayPorts=yes */
2808: addr = listen_addr;
1.326 djm 2809: }
1.334 djm 2810: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
2811: strcmp(listen_addr, "::1") == 0) {
2812: /*
2813: * If a specific IPv4/IPv6 localhost address has been
2814: * requested then accept it even if gateway_ports is in
2815: * effect. This allows the client to prefer IPv4 or IPv6.
2816: */
2817: addr = listen_addr;
1.312 djm 2818: }
2819: if (wildcardp != NULL)
2820: *wildcardp = wildcard;
2821: return addr;
2822: }
2823:
1.160 markus 2824: static int
1.336 millert 2825: channel_setup_fwd_listener_tcpip(int type, struct Forward *fwd,
2826: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.25 markus 2827: {
1.113 markus 2828: Channel *c;
1.226 djm 2829: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2830: struct addrinfo hints, *ai, *aitop;
1.212 djm 2831: const char *host, *addr;
1.35 markus 2832: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2833: in_port_t *lport_p;
1.25 markus 2834:
1.212 djm 2835: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2836:
1.344 millert 2837: if (is_client && fwd->connect_path != NULL) {
2838: host = fwd->connect_path;
2839: } else {
2840: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2841: fwd->listen_host : fwd->connect_host;
2842: if (host == NULL) {
2843: error("No forward host name.");
2844: return 0;
2845: }
2846: if (strlen(host) >= NI_MAXHOST) {
2847: error("Forward host name too long.");
2848: return 0;
2849: }
1.87 markus 2850: }
1.25 markus 2851:
1.312 djm 2852: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 2853: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
2854: is_client, fwd_opts);
2855: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 2856: type, wildcard, (addr == NULL) ? "NULL" : addr);
2857:
2858: /*
1.35 markus 2859: * getaddrinfo returns a loopback address if the hostname is
2860: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2861: */
1.35 markus 2862: memset(&hints, 0, sizeof(hints));
2863: hints.ai_family = IPv4or6;
1.212 djm 2864: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2865: hints.ai_socktype = SOCK_STREAM;
1.336 millert 2866: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 2867: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2868: if (addr == NULL) {
2869: /* This really shouldn't happen */
2870: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2871: ssh_gai_strerror(r));
1.212 djm 2872: } else {
1.336 millert 2873: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 2874: ssh_gai_strerror(r));
1.212 djm 2875: }
1.218 markus 2876: return 0;
1.212 djm 2877: }
1.295 djm 2878: if (allocated_listen_port != NULL)
2879: *allocated_listen_port = 0;
1.35 markus 2880: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2881: switch (ai->ai_family) {
2882: case AF_INET:
2883: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2884: sin_port;
2885: break;
2886: case AF_INET6:
2887: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2888: sin6_port;
2889: break;
2890: default:
1.35 markus 2891: continue;
1.295 djm 2892: }
2893: /*
2894: * If allocating a port for -R forwards, then use the
2895: * same port for all address families.
2896: */
1.336 millert 2897: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2898: allocated_listen_port != NULL && *allocated_listen_port > 0)
2899: *lport_p = htons(*allocated_listen_port);
2900:
1.35 markus 2901: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2902: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 2903: error("%s: getnameinfo failed", __func__);
1.35 markus 2904: continue;
2905: }
2906: /* Create a port to listen for the host. */
1.300 dtucker 2907: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2908: if (sock < 0) {
2909: /* this is no error since kernel may not support ipv6 */
2910: verbose("socket: %.100s", strerror(errno));
2911: continue;
2912: }
1.226 djm 2913:
2914: channel_set_reuseaddr(sock);
1.182 stevesk 2915:
1.295 djm 2916: debug("Local forwarding listening on %s port %s.",
2917: ntop, strport);
1.35 markus 2918:
2919: /* Bind the socket to the address. */
2920: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2921: /* address can be in use ipv6 address is already bound */
2922: verbose("bind: %.100s", strerror(errno));
2923: close(sock);
2924: continue;
2925: }
2926: /* Start listening for connections on the socket. */
1.199 markus 2927: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2928: error("listen: %.100s", strerror(errno));
2929: close(sock);
2930: continue;
2931: }
1.295 djm 2932:
2933: /*
1.336 millert 2934: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 2935: * record what we got.
2936: */
1.336 millert 2937: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2938: allocated_listen_port != NULL &&
2939: *allocated_listen_port == 0) {
1.350 djm 2940: *allocated_listen_port = get_local_port(sock);
1.295 djm 2941: debug("Allocated listen port %d",
2942: *allocated_listen_port);
2943: }
2944:
1.35 markus 2945: /* Allocate a channel number for the socket. */
1.121 markus 2946: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2947: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2948: 0, "port listener", 1);
1.293 djm 2949: c->path = xstrdup(host);
1.336 millert 2950: c->host_port = fwd->connect_port;
1.312 djm 2951: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 2952: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 2953: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
2954: c->listening_port = *allocated_listen_port;
2955: else
1.336 millert 2956: c->listening_port = fwd->listen_port;
1.35 markus 2957: success = 1;
2958: }
2959: if (success == 0)
1.336 millert 2960: error("%s: cannot listen to port: %d", __func__,
2961: fwd->listen_port);
1.35 markus 2962: freeaddrinfo(aitop);
1.87 markus 2963: return success;
1.25 markus 2964: }
1.1 deraadt 2965:
1.336 millert 2966: static int
2967: channel_setup_fwd_listener_streamlocal(int type, struct Forward *fwd,
2968: struct ForwardOptions *fwd_opts)
2969: {
2970: struct sockaddr_un sunaddr;
2971: const char *path;
2972: Channel *c;
2973: int port, sock;
2974: mode_t omask;
2975:
2976: switch (type) {
2977: case SSH_CHANNEL_UNIX_LISTENER:
2978: if (fwd->connect_path != NULL) {
2979: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
2980: error("Local connecting path too long: %s",
2981: fwd->connect_path);
2982: return 0;
2983: }
2984: path = fwd->connect_path;
2985: port = PORT_STREAMLOCAL;
2986: } else {
2987: if (fwd->connect_host == NULL) {
2988: error("No forward host name.");
2989: return 0;
2990: }
2991: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
2992: error("Forward host name too long.");
2993: return 0;
2994: }
2995: path = fwd->connect_host;
2996: port = fwd->connect_port;
2997: }
2998: break;
2999: case SSH_CHANNEL_RUNIX_LISTENER:
3000: path = fwd->listen_path;
3001: port = PORT_STREAMLOCAL;
3002: break;
3003: default:
3004: error("%s: unexpected channel type %d", __func__, type);
3005: return 0;
3006: }
3007:
3008: if (fwd->listen_path == NULL) {
3009: error("No forward path name.");
3010: return 0;
3011: }
3012: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3013: error("Local listening path too long: %s", fwd->listen_path);
3014: return 0;
3015: }
3016:
3017: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3018:
3019: /* Start a Unix domain listener. */
3020: omask = umask(fwd_opts->streamlocal_bind_mask);
3021: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3022: fwd_opts->streamlocal_bind_unlink);
3023: umask(omask);
3024: if (sock < 0)
3025: return 0;
3026:
3027: debug("Local forwarding listening on path %s.", fwd->listen_path);
3028:
3029: /* Allocate a channel number for the socket. */
3030: c = channel_new("unix listener", type, sock, sock, -1,
3031: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3032: 0, "unix listener", 1);
3033: c->path = xstrdup(path);
3034: c->host_port = port;
3035: c->listening_port = PORT_STREAMLOCAL;
3036: c->listening_addr = xstrdup(fwd->listen_path);
3037: return 1;
3038: }
3039:
3040: static int
3041: channel_cancel_rport_listener_tcpip(const char *host, u_short port)
1.202 djm 3042: {
1.209 avsm 3043: u_int i;
3044: int found = 0;
1.202 djm 3045:
1.213 deraadt 3046: for (i = 0; i < channels_alloc; i++) {
1.202 djm 3047: Channel *c = channels[i];
1.312 djm 3048: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3049: continue;
3050: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3051: debug2("%s: close channel %d", __func__, i);
3052: channel_free(c);
3053: found = 1;
3054: }
3055: }
3056:
3057: return (found);
3058: }
3059:
1.336 millert 3060: static int
3061: channel_cancel_rport_listener_streamlocal(const char *path)
3062: {
3063: u_int i;
3064: int found = 0;
3065:
3066: for (i = 0; i < channels_alloc; i++) {
3067: Channel *c = channels[i];
3068: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3069: continue;
3070: if (c->path == NULL)
3071: continue;
3072: if (strcmp(c->path, path) == 0) {
3073: debug2("%s: close channel %d", __func__, i);
3074: channel_free(c);
3075: found = 1;
3076: }
3077: }
3078:
3079: return (found);
3080: }
3081:
1.312 djm 3082: int
1.336 millert 3083: channel_cancel_rport_listener(struct Forward *fwd)
3084: {
3085: if (fwd->listen_path != NULL)
3086: return channel_cancel_rport_listener_streamlocal(fwd->listen_path);
3087: else
3088: return channel_cancel_rport_listener_tcpip(fwd->listen_host, fwd->listen_port);
3089: }
3090:
3091: static int
3092: channel_cancel_lport_listener_tcpip(const char *lhost, u_short lport,
3093: int cport, struct ForwardOptions *fwd_opts)
1.312 djm 3094: {
3095: u_int i;
3096: int found = 0;
1.336 millert 3097: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3098:
1.312 djm 3099: for (i = 0; i < channels_alloc; i++) {
3100: Channel *c = channels[i];
3101: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3102: continue;
1.313 markus 3103: if (c->listening_port != lport)
1.312 djm 3104: continue;
1.313 markus 3105: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3106: /* skip dynamic forwardings */
3107: if (c->host_port == 0)
3108: continue;
3109: } else {
3110: if (c->host_port != cport)
3111: continue;
3112: }
1.312 djm 3113: if ((c->listening_addr == NULL && addr != NULL) ||
3114: (c->listening_addr != NULL && addr == NULL))
3115: continue;
3116: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3117: debug2("%s: close channel %d", __func__, i);
1.202 djm 3118: channel_free(c);
3119: found = 1;
3120: }
3121: }
3122:
3123: return (found);
3124: }
3125:
1.336 millert 3126: static int
3127: channel_cancel_lport_listener_streamlocal(const char *path)
3128: {
3129: u_int i;
3130: int found = 0;
3131:
3132: if (path == NULL) {
3133: error("%s: no path specified.", __func__);
3134: return 0;
3135: }
3136:
3137: for (i = 0; i < channels_alloc; i++) {
3138: Channel *c = channels[i];
3139: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3140: continue;
3141: if (c->listening_addr == NULL)
3142: continue;
3143: if (strcmp(c->listening_addr, path) == 0) {
3144: debug2("%s: close channel %d", __func__, i);
3145: channel_free(c);
3146: found = 1;
3147: }
3148: }
3149:
3150: return (found);
3151: }
3152:
3153: int
3154: channel_cancel_lport_listener(struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
3155: {
3156: if (fwd->listen_path != NULL)
3157: return channel_cancel_lport_listener_streamlocal(fwd->listen_path);
3158: else
3159: return channel_cancel_lport_listener_tcpip(fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3160: }
3161:
1.362 markus 3162: /* protocol local port fwd, used by ssh */
1.160 markus 3163: int
1.336 millert 3164: channel_setup_local_fwd_listener(struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3165: {
1.336 millert 3166: if (fwd->listen_path != NULL) {
3167: return channel_setup_fwd_listener_streamlocal(
3168: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3169: } else {
3170: return channel_setup_fwd_listener_tcpip(SSH_CHANNEL_PORT_LISTENER,
3171: fwd, NULL, fwd_opts);
3172: }
1.160 markus 3173: }
3174:
3175: /* protocol v2 remote port fwd, used by sshd */
3176: int
1.336 millert 3177: channel_setup_remote_fwd_listener(struct Forward *fwd,
3178: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3179: {
1.336 millert 3180: if (fwd->listen_path != NULL) {
3181: return channel_setup_fwd_listener_streamlocal(
3182: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3183: } else {
3184: return channel_setup_fwd_listener_tcpip(
3185: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3186: fwd_opts);
3187: }
1.160 markus 3188: }
3189:
1.27 markus 3190: /*
1.312 djm 3191: * Translate the requested rfwd listen host to something usable for
3192: * this server.
3193: */
3194: static const char *
3195: channel_rfwd_bind_host(const char *listen_host)
3196: {
3197: if (listen_host == NULL) {
3198: if (datafellows & SSH_BUG_RFWD_ADDR)
3199: return "127.0.0.1";
3200: else
3201: return "localhost";
3202: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3203: if (datafellows & SSH_BUG_RFWD_ADDR)
3204: return "0.0.0.0";
3205: else
3206: return "";
3207: } else
3208: return listen_host;
3209: }
3210:
3211: /*
1.27 markus 3212: * Initiate forwarding of connections to port "port" on remote host through
3213: * the secure channel to host:port from local side.
1.315 markus 3214: * Returns handle (index) for updating the dynamic listen port with
3215: * channel_update_permitted_opens().
1.27 markus 3216: */
1.253 markus 3217: int
1.336 millert 3218: channel_request_remote_forwarding(struct Forward *fwd)
1.25 markus 3219: {
1.358 djm 3220: int success = 0, idx = -1;
1.73 markus 3221:
1.25 markus 3222: /* Send the forward request to the remote side. */
1.358 djm 3223: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3224: if (fwd->listen_path != NULL) {
3225: packet_put_cstring("streamlocal-forward@openssh.com");
3226: packet_put_char(1); /* boolean: want reply */
3227: packet_put_cstring(fwd->listen_path);
1.336 millert 3228: } else {
1.358 djm 3229: packet_put_cstring("tcpip-forward");
3230: packet_put_char(1); /* boolean: want reply */
3231: packet_put_cstring(channel_rfwd_bind_host(fwd->listen_host));
3232: packet_put_int(fwd->listen_port);
1.73 markus 3233: }
1.358 djm 3234: packet_send();
3235: packet_write_wait();
3236: /* Assume that server accepts the request */
3237: success = 1;
1.73 markus 3238: if (success) {
1.305 djm 3239: /* Record that connection to this host/port is permitted. */
1.342 deraadt 3240: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3241: num_permitted_opens + 1, sizeof(*permitted_opens));
1.315 markus 3242: idx = num_permitted_opens++;
1.336 millert 3243: if (fwd->connect_path != NULL) {
3244: permitted_opens[idx].host_to_connect =
3245: xstrdup(fwd->connect_path);
3246: permitted_opens[idx].port_to_connect =
3247: PORT_STREAMLOCAL;
3248: } else {
3249: permitted_opens[idx].host_to_connect =
3250: xstrdup(fwd->connect_host);
3251: permitted_opens[idx].port_to_connect =
3252: fwd->connect_port;
3253: }
3254: if (fwd->listen_path != NULL) {
3255: permitted_opens[idx].listen_host = NULL;
3256: permitted_opens[idx].listen_path =
3257: xstrdup(fwd->listen_path);
3258: permitted_opens[idx].listen_port = PORT_STREAMLOCAL;
3259: } else {
3260: permitted_opens[idx].listen_host =
3261: fwd->listen_host ? xstrdup(fwd->listen_host) : NULL;
3262: permitted_opens[idx].listen_path = NULL;
3263: permitted_opens[idx].listen_port = fwd->listen_port;
3264: }
1.354 markus 3265: permitted_opens[idx].downstream = NULL;
1.44 markus 3266: }
1.315 markus 3267: return (idx);
1.1 deraadt 3268: }
3269:
1.333 markus 3270: static int
3271: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3272: int requestedport)
1.333 markus 3273: {
3274: if (allowed_open->host_to_connect == NULL)
3275: return 0;
3276: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3277: allowed_open->port_to_connect != requestedport)
3278: return 0;
1.351 dtucker 3279: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3280: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3281: return 0;
3282: return 1;
3283: }
3284:
3285: /*
1.336 millert 3286: * Note that in the listen host/port case
1.333 markus 3287: * we don't support FWD_PERMIT_ANY_PORT and
3288: * need to translate between the configured-host (listen_host)
3289: * and what we've sent to the remote server (channel_rfwd_bind_host)
3290: */
3291: static int
1.336 millert 3292: open_listen_match_tcpip(ForwardPermission *allowed_open,
3293: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3294: {
3295: const char *allowed_host;
3296:
3297: if (allowed_open->host_to_connect == NULL)
3298: return 0;
3299: if (allowed_open->listen_port != requestedport)
3300: return 0;
1.335 djm 3301: if (!translate && allowed_open->listen_host == NULL &&
3302: requestedhost == NULL)
3303: return 1;
1.333 markus 3304: allowed_host = translate ?
3305: channel_rfwd_bind_host(allowed_open->listen_host) :
3306: allowed_open->listen_host;
3307: if (allowed_host == NULL ||
3308: strcmp(allowed_host, requestedhost) != 0)
3309: return 0;
3310: return 1;
3311: }
3312:
1.336 millert 3313: static int
3314: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3315: const char *requestedpath)
3316: {
3317: if (allowed_open->host_to_connect == NULL)
3318: return 0;
3319: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3320: return 0;
3321: if (allowed_open->listen_path == NULL ||
3322: strcmp(allowed_open->listen_path, requestedpath) != 0)
3323: return 0;
3324: return 1;
3325: }
3326:
1.27 markus 3327: /*
1.208 deraadt 3328: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3329: * local side.
3330: */
1.336 millert 3331: static int
3332: channel_request_rforward_cancel_tcpip(const char *host, u_short port)
1.202 djm 3333: {
3334: int i;
3335:
3336: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3337: if (open_listen_match_tcpip(&permitted_opens[i], host, port, 0))
1.202 djm 3338: break;
3339: }
3340: if (i >= num_permitted_opens) {
3341: debug("%s: requested forward not found", __func__);
1.312 djm 3342: return -1;
1.202 djm 3343: }
3344: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3345: packet_put_cstring("cancel-tcpip-forward");
3346: packet_put_char(0);
1.312 djm 3347: packet_put_cstring(channel_rfwd_bind_host(host));
1.202 djm 3348: packet_put_int(port);
3349: packet_send();
3350:
1.336 millert 3351: permitted_opens[i].listen_port = 0;
1.333 markus 3352: permitted_opens[i].port_to_connect = 0;
1.336 millert 3353: free(permitted_opens[i].host_to_connect);
3354: permitted_opens[i].host_to_connect = NULL;
3355: free(permitted_opens[i].listen_host);
3356: permitted_opens[i].listen_host = NULL;
3357: permitted_opens[i].listen_path = NULL;
1.354 markus 3358: permitted_opens[i].downstream = NULL;
1.336 millert 3359:
3360: return 0;
3361: }
3362:
3363: /*
3364: * Request cancellation of remote forwarding of Unix domain socket
3365: * path from local side.
3366: */
3367: static int
3368: channel_request_rforward_cancel_streamlocal(const char *path)
3369: {
3370: int i;
3371:
3372: for (i = 0; i < num_permitted_opens; i++) {
3373: if (open_listen_match_streamlocal(&permitted_opens[i], path))
3374: break;
3375: }
3376: if (i >= num_permitted_opens) {
3377: debug("%s: requested forward not found", __func__);
3378: return -1;
3379: }
3380: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3381: packet_put_cstring("cancel-streamlocal-forward@openssh.com");
3382: packet_put_char(0);
3383: packet_put_cstring(path);
3384: packet_send();
3385:
1.202 djm 3386: permitted_opens[i].listen_port = 0;
1.336 millert 3387: permitted_opens[i].port_to_connect = 0;
1.321 djm 3388: free(permitted_opens[i].host_to_connect);
1.202 djm 3389: permitted_opens[i].host_to_connect = NULL;
1.333 markus 3390: permitted_opens[i].listen_host = NULL;
1.336 millert 3391: free(permitted_opens[i].listen_path);
3392: permitted_opens[i].listen_path = NULL;
1.354 markus 3393: permitted_opens[i].downstream = NULL;
1.312 djm 3394:
3395: return 0;
1.202 djm 3396: }
3397:
3398: /*
1.336 millert 3399: * Request cancellation of remote forwarding of a connection from local side.
3400: */
3401: int
3402: channel_request_rforward_cancel(struct Forward *fwd)
3403: {
3404: if (fwd->listen_path != NULL) {
3405: return (channel_request_rforward_cancel_streamlocal(
3406: fwd->listen_path));
3407: } else {
3408: return (channel_request_rforward_cancel_tcpip(fwd->listen_host,
3409: fwd->listen_port ? fwd->listen_port : fwd->allocated_port));
3410: }
1.1 deraadt 3411: }
3412:
1.99 markus 3413: /*
3414: * Permits opening to any host/port if permitted_opens[] is empty. This is
3415: * usually called by the server, because the user could connect to any port
3416: * anyway, and the server has no way to know but to trust the client anyway.
3417: */
3418: void
1.142 itojun 3419: channel_permit_all_opens(void)
1.99 markus 3420: {
3421: if (num_permitted_opens == 0)
3422: all_opens_permitted = 1;
3423: }
3424:
1.101 markus 3425: void
1.99 markus 3426: channel_add_permitted_opens(char *host, int port)
3427: {
3428: debug("allow port forwarding to host %s port %d", host, port);
3429:
1.342 deraadt 3430: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3431: num_permitted_opens + 1, sizeof(*permitted_opens));
1.99 markus 3432: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
3433: permitted_opens[num_permitted_opens].port_to_connect = port;
1.333 markus 3434: permitted_opens[num_permitted_opens].listen_host = NULL;
1.336 millert 3435: permitted_opens[num_permitted_opens].listen_path = NULL;
1.333 markus 3436: permitted_opens[num_permitted_opens].listen_port = 0;
1.354 markus 3437: permitted_opens[num_permitted_opens].downstream = NULL;
1.99 markus 3438: num_permitted_opens++;
3439:
3440: all_opens_permitted = 0;
1.315 markus 3441: }
3442:
3443: /*
3444: * Update the listen port for a dynamic remote forward, after
3445: * the actual 'newport' has been allocated. If 'newport' < 0 is
3446: * passed then they entry will be invalidated.
3447: */
3448: void
3449: channel_update_permitted_opens(int idx, int newport)
3450: {
3451: if (idx < 0 || idx >= num_permitted_opens) {
3452: debug("channel_update_permitted_opens: index out of range:"
3453: " %d num_permitted_opens %d", idx, num_permitted_opens);
3454: return;
3455: }
3456: debug("%s allowed port %d for forwarding to host %s port %d",
3457: newport > 0 ? "Updating" : "Removing",
3458: newport,
3459: permitted_opens[idx].host_to_connect,
3460: permitted_opens[idx].port_to_connect);
3461: if (newport >= 0) {
3462: permitted_opens[idx].listen_port =
3463: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3464: } else {
3465: permitted_opens[idx].listen_port = 0;
3466: permitted_opens[idx].port_to_connect = 0;
1.321 djm 3467: free(permitted_opens[idx].host_to_connect);
1.315 markus 3468: permitted_opens[idx].host_to_connect = NULL;
1.333 markus 3469: free(permitted_opens[idx].listen_host);
3470: permitted_opens[idx].listen_host = NULL;
1.336 millert 3471: free(permitted_opens[idx].listen_path);
3472: permitted_opens[idx].listen_path = NULL;
1.315 markus 3473: }
1.99 markus 3474: }
3475:
1.258 dtucker 3476: int
1.257 dtucker 3477: channel_add_adm_permitted_opens(char *host, int port)
3478: {
1.258 dtucker 3479: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 3480:
1.342 deraadt 3481: permitted_adm_opens = xreallocarray(permitted_adm_opens,
1.305 djm 3482: num_adm_permitted_opens + 1, sizeof(*permitted_adm_opens));
1.257 dtucker 3483: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
3484: = xstrdup(host);
3485: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.333 markus 3486: permitted_adm_opens[num_adm_permitted_opens].listen_host = NULL;
1.336 millert 3487: permitted_adm_opens[num_adm_permitted_opens].listen_path = NULL;
1.333 markus 3488: permitted_adm_opens[num_adm_permitted_opens].listen_port = 0;
1.258 dtucker 3489: return ++num_adm_permitted_opens;
1.257 dtucker 3490: }
3491:
3492: void
1.316 dtucker 3493: channel_disable_adm_local_opens(void)
3494: {
1.319 djm 3495: channel_clear_adm_permitted_opens();
1.343 dtucker 3496: permitted_adm_opens = xcalloc(sizeof(*permitted_adm_opens), 1);
1.319 djm 3497: permitted_adm_opens[num_adm_permitted_opens].host_to_connect = NULL;
3498: num_adm_permitted_opens = 1;
1.316 dtucker 3499: }
3500:
3501: void
1.99 markus 3502: channel_clear_permitted_opens(void)
3503: {
3504: int i;
3505:
1.333 markus 3506: for (i = 0; i < num_permitted_opens; i++) {
1.321 djm 3507: free(permitted_opens[i].host_to_connect);
1.333 markus 3508: free(permitted_opens[i].listen_host);
1.336 millert 3509: free(permitted_opens[i].listen_path);
1.333 markus 3510: }
1.321 djm 3511: free(permitted_opens);
3512: permitted_opens = NULL;
1.99 markus 3513: num_permitted_opens = 0;
1.257 dtucker 3514: }
3515:
3516: void
3517: channel_clear_adm_permitted_opens(void)
3518: {
3519: int i;
1.99 markus 3520:
1.333 markus 3521: for (i = 0; i < num_adm_permitted_opens; i++) {
1.321 djm 3522: free(permitted_adm_opens[i].host_to_connect);
1.333 markus 3523: free(permitted_adm_opens[i].listen_host);
1.336 millert 3524: free(permitted_adm_opens[i].listen_path);
1.333 markus 3525: }
1.321 djm 3526: free(permitted_adm_opens);
3527: permitted_adm_opens = NULL;
1.257 dtucker 3528: num_adm_permitted_opens = 0;
1.278 dtucker 3529: }
3530:
3531: void
3532: channel_print_adm_permitted_opens(void)
3533: {
1.286 djm 3534: int i;
1.278 dtucker 3535:
1.290 stevesk 3536: printf("permitopen");
1.288 stevesk 3537: if (num_adm_permitted_opens == 0) {
1.290 stevesk 3538: printf(" any\n");
1.288 stevesk 3539: return;
3540: }
1.278 dtucker 3541: for (i = 0; i < num_adm_permitted_opens; i++)
1.316 dtucker 3542: if (permitted_adm_opens[i].host_to_connect == NULL)
3543: printf(" none");
3544: else
1.278 dtucker 3545: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
3546: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 3547: printf("\n");
1.99 markus 3548: }
3549:
1.314 dtucker 3550: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3551: int
3552: permitopen_port(const char *p)
3553: {
3554: int port;
3555:
3556: if (strcmp(p, "*") == 0)
3557: return FWD_PERMIT_ANY_PORT;
3558: if ((port = a2port(p)) > 0)
3559: return port;
3560: return -1;
3561: }
3562:
1.276 djm 3563: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3564: static int
1.276 djm 3565: connect_next(struct channel_connect *cctx)
1.41 markus 3566: {
1.276 djm 3567: int sock, saved_errno;
1.336 millert 3568: struct sockaddr_un *sunaddr;
1.352 deraadt 3569: char ntop[NI_MAXHOST], strport[MAXIMUM(NI_MAXSERV,sizeof(sunaddr->sun_path))];
1.41 markus 3570:
1.276 djm 3571: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3572: switch (cctx->ai->ai_family) {
3573: case AF_UNIX:
3574: /* unix:pathname instead of host:port */
3575: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3576: strlcpy(ntop, "unix", sizeof(ntop));
3577: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3578: break;
3579: case AF_INET:
3580: case AF_INET6:
3581: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3582: ntop, sizeof(ntop), strport, sizeof(strport),
3583: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3584: error("connect_next: getnameinfo failed");
3585: continue;
3586: }
3587: break;
3588: default:
1.41 markus 3589: continue;
3590: }
1.300 dtucker 3591: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3592: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3593: if (cctx->ai->ai_next == NULL)
1.186 djm 3594: error("socket: %.100s", strerror(errno));
3595: else
3596: verbose("socket: %.100s", strerror(errno));
1.41 markus 3597: continue;
3598: }
1.205 djm 3599: if (set_nonblock(sock) == -1)
3600: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3601: if (connect(sock, cctx->ai->ai_addr,
3602: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3603: debug("connect_next: host %.100s ([%.100s]:%s): "
3604: "%.100s", cctx->host, ntop, strport,
1.41 markus 3605: strerror(errno));
1.276 djm 3606: saved_errno = errno;
1.41 markus 3607: close(sock);
1.276 djm 3608: errno = saved_errno;
1.89 stevesk 3609: continue; /* fail -- try next */
1.41 markus 3610: }
1.336 millert 3611: if (cctx->ai->ai_family != AF_UNIX)
3612: set_nodelay(sock);
1.276 djm 3613: debug("connect_next: host %.100s ([%.100s]:%s) "
3614: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3615: cctx->ai = cctx->ai->ai_next;
3616: return sock;
3617: }
3618: return -1;
3619: }
1.41 markus 3620:
1.276 djm 3621: static void
3622: channel_connect_ctx_free(struct channel_connect *cctx)
3623: {
1.321 djm 3624: free(cctx->host);
1.336 millert 3625: if (cctx->aitop) {
3626: if (cctx->aitop->ai_family == AF_UNIX)
3627: free(cctx->aitop);
3628: else
3629: freeaddrinfo(cctx->aitop);
3630: }
1.329 tedu 3631: memset(cctx, 0, sizeof(*cctx));
1.276 djm 3632: }
3633:
1.357 dtucker 3634: /*
3635: * Return CONNECTING channel to remote host:port or local socket path,
3636: * passing back the failure reason if appropriate.
3637: */
1.276 djm 3638: static Channel *
1.357 dtucker 3639: connect_to_reason(const char *name, int port, char *ctype, char *rname,
3640: int *reason, const char **errmsg)
1.276 djm 3641: {
3642: struct addrinfo hints;
3643: int gaierr;
3644: int sock = -1;
3645: char strport[NI_MAXSERV];
3646: struct channel_connect cctx;
3647: Channel *c;
3648:
1.284 djm 3649: memset(&cctx, 0, sizeof(cctx));
1.336 millert 3650:
3651: if (port == PORT_STREAMLOCAL) {
3652: struct sockaddr_un *sunaddr;
3653: struct addrinfo *ai;
3654:
3655: if (strlen(name) > sizeof(sunaddr->sun_path)) {
3656: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
3657: return (NULL);
3658: }
3659:
3660: /*
3661: * Fake up a struct addrinfo for AF_UNIX connections.
3662: * channel_connect_ctx_free() must check ai_family
3663: * and use free() not freeaddirinfo() for AF_UNIX.
3664: */
3665: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
3666: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
3667: ai->ai_addr = (struct sockaddr *)(ai + 1);
3668: ai->ai_addrlen = sizeof(*sunaddr);
3669: ai->ai_family = AF_UNIX;
3670: ai->ai_socktype = SOCK_STREAM;
3671: ai->ai_protocol = PF_UNSPEC;
3672: sunaddr = (struct sockaddr_un *)ai->ai_addr;
3673: sunaddr->sun_family = AF_UNIX;
3674: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
3675: cctx.aitop = ai;
3676: } else {
3677: memset(&hints, 0, sizeof(hints));
3678: hints.ai_family = IPv4or6;
3679: hints.ai_socktype = SOCK_STREAM;
3680: snprintf(strport, sizeof strport, "%d", port);
1.357 dtucker 3681: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx.aitop))
3682: != 0) {
3683: if (errmsg != NULL)
3684: *errmsg = ssh_gai_strerror(gaierr);
3685: if (reason != NULL)
3686: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 3687: error("connect_to %.100s: unknown host (%s)", name,
3688: ssh_gai_strerror(gaierr));
3689: return NULL;
3690: }
1.41 markus 3691: }
1.276 djm 3692:
1.336 millert 3693: cctx.host = xstrdup(name);
1.276 djm 3694: cctx.port = port;
3695: cctx.ai = cctx.aitop;
3696:
3697: if ((sock = connect_next(&cctx)) == -1) {
3698: error("connect to %.100s port %d failed: %s",
1.336 millert 3699: name, port, strerror(errno));
1.276 djm 3700: channel_connect_ctx_free(&cctx);
3701: return NULL;
1.41 markus 3702: }
1.276 djm 3703: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
3704: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
3705: c->connect_ctx = cctx;
3706: return c;
1.41 markus 3707: }
1.99 markus 3708:
1.357 dtucker 3709: /* Return CONNECTING channel to remote host:port or local socket path */
3710: static Channel *
3711: connect_to(const char *name, int port, char *ctype, char *rname)
3712: {
3713: return connect_to_reason(name, port, ctype, rname, NULL, NULL);
3714: }
3715:
1.354 markus 3716: /*
3717: * returns either the newly connected channel or the downstream channel
3718: * that needs to deal with this connection.
3719: */
1.276 djm 3720: Channel *
1.333 markus 3721: channel_connect_by_listen_address(const char *listen_host,
3722: u_short listen_port, char *ctype, char *rname)
1.73 markus 3723: {
3724: int i;
1.99 markus 3725:
1.276 djm 3726: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3727: if (open_listen_match_tcpip(&permitted_opens[i], listen_host,
1.333 markus 3728: listen_port, 1)) {
1.354 markus 3729: if (permitted_opens[i].downstream)
3730: return permitted_opens[i].downstream;
1.99 markus 3731: return connect_to(
1.73 markus 3732: permitted_opens[i].host_to_connect,
1.276 djm 3733: permitted_opens[i].port_to_connect, ctype, rname);
3734: }
3735: }
1.74 markus 3736: error("WARNING: Server requests forwarding for unknown listen_port %d",
3737: listen_port);
1.276 djm 3738: return NULL;
1.73 markus 3739: }
3740:
1.336 millert 3741: Channel *
3742: channel_connect_by_listen_path(const char *path, char *ctype, char *rname)
3743: {
3744: int i;
3745:
3746: for (i = 0; i < num_permitted_opens; i++) {
3747: if (open_listen_match_streamlocal(&permitted_opens[i], path)) {
3748: return connect_to(
3749: permitted_opens[i].host_to_connect,
3750: permitted_opens[i].port_to_connect, ctype, rname);
3751: }
3752: }
3753: error("WARNING: Server requests forwarding for unknown path %.100s",
3754: path);
3755: return NULL;
3756: }
3757:
1.99 markus 3758: /* Check if connecting to that port is permitted and connect. */
1.276 djm 3759: Channel *
1.357 dtucker 3760: channel_connect_to_port(const char *host, u_short port, char *ctype,
3761: char *rname, int *reason, const char **errmsg)
1.99 markus 3762: {
1.257 dtucker 3763: int i, permit, permit_adm = 1;
1.99 markus 3764:
3765: permit = all_opens_permitted;
3766: if (!permit) {
3767: for (i = 0; i < num_permitted_opens; i++)
1.333 markus 3768: if (open_match(&permitted_opens[i], host, port)) {
1.99 markus 3769: permit = 1;
1.333 markus 3770: break;
3771: }
1.257 dtucker 3772: }
1.99 markus 3773:
1.257 dtucker 3774: if (num_adm_permitted_opens > 0) {
3775: permit_adm = 0;
3776: for (i = 0; i < num_adm_permitted_opens; i++)
1.333 markus 3777: if (open_match(&permitted_adm_opens[i], host, port)) {
1.257 dtucker 3778: permit_adm = 1;
1.333 markus 3779: break;
3780: }
1.99 markus 3781: }
1.257 dtucker 3782:
3783: if (!permit || !permit_adm) {
1.188 itojun 3784: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3785: "but the request was denied.", host, port);
1.357 dtucker 3786: if (reason != NULL)
3787: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 3788: return NULL;
1.99 markus 3789: }
1.357 dtucker 3790: return connect_to_reason(host, port, ctype, rname, reason, errmsg);
1.336 millert 3791: }
3792:
3793: /* Check if connecting to that path is permitted and connect. */
3794: Channel *
3795: channel_connect_to_path(const char *path, char *ctype, char *rname)
3796: {
3797: int i, permit, permit_adm = 1;
3798:
3799: permit = all_opens_permitted;
3800: if (!permit) {
3801: for (i = 0; i < num_permitted_opens; i++)
3802: if (open_match(&permitted_opens[i], path, PORT_STREAMLOCAL)) {
3803: permit = 1;
3804: break;
3805: }
3806: }
3807:
3808: if (num_adm_permitted_opens > 0) {
3809: permit_adm = 0;
3810: for (i = 0; i < num_adm_permitted_opens; i++)
3811: if (open_match(&permitted_adm_opens[i], path, PORT_STREAMLOCAL)) {
3812: permit_adm = 1;
3813: break;
3814: }
3815: }
3816:
3817: if (!permit || !permit_adm) {
3818: logit("Received request to connect to path %.100s, "
3819: "but the request was denied.", path);
3820: return NULL;
3821: }
3822: return connect_to(path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 3823: }
3824:
3825: void
3826: channel_send_window_changes(void)
3827: {
1.209 avsm 3828: u_int i;
1.204 djm 3829: struct winsize ws;
3830:
3831: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3832: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3833: channels[i]->type != SSH_CHANNEL_OPEN)
3834: continue;
3835: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3836: continue;
3837: channel_request_start(i, "window-change", 0);
1.238 deraadt 3838: packet_put_int((u_int)ws.ws_col);
3839: packet_put_int((u_int)ws.ws_row);
3840: packet_put_int((u_int)ws.ws_xpixel);
3841: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3842: packet_send();
3843: }
1.99 markus 3844: }
3845:
1.121 markus 3846: /* -- X11 forwarding */
1.1 deraadt 3847:
1.27 markus 3848: /*
3849: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3850: * Returns 0 and a suitable display number for the DISPLAY variable
3851: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3852: */
1.141 stevesk 3853: int
1.163 stevesk 3854: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3855: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3856: {
1.149 markus 3857: Channel *nc = NULL;
1.31 markus 3858: int display_number, sock;
3859: u_short port;
1.35 markus 3860: struct addrinfo hints, *ai, *aitop;
3861: char strport[NI_MAXSERV];
3862: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3863:
1.224 markus 3864: if (chanids == NULL)
3865: return -1;
3866:
1.33 markus 3867: for (display_number = x11_display_offset;
1.148 deraadt 3868: display_number < MAX_DISPLAYS;
3869: display_number++) {
1.25 markus 3870: port = 6000 + display_number;
1.35 markus 3871: memset(&hints, 0, sizeof(hints));
3872: hints.ai_family = IPv4or6;
1.163 stevesk 3873: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3874: hints.ai_socktype = SOCK_STREAM;
3875: snprintf(strport, sizeof strport, "%d", port);
3876: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3877: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3878: return -1;
1.25 markus 3879: }
1.35 markus 3880: for (ai = aitop; ai; ai = ai->ai_next) {
3881: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3882: continue;
1.300 dtucker 3883: sock = socket(ai->ai_family, ai->ai_socktype,
3884: ai->ai_protocol);
1.35 markus 3885: if (sock < 0) {
3886: error("socket: %.100s", strerror(errno));
1.203 markus 3887: freeaddrinfo(aitop);
1.141 stevesk 3888: return -1;
1.35 markus 3889: }
1.226 djm 3890: channel_set_reuseaddr(sock);
1.35 markus 3891: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3892: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3893: close(sock);
1.183 itojun 3894:
1.35 markus 3895: for (n = 0; n < num_socks; n++) {
3896: close(socks[n]);
3897: }
3898: num_socks = 0;
3899: break;
3900: }
3901: socks[num_socks++] = sock;
3902: if (num_socks == NUM_SOCKS)
3903: break;
1.25 markus 3904: }
1.83 stevesk 3905: freeaddrinfo(aitop);
1.35 markus 3906: if (num_socks > 0)
3907: break;
1.25 markus 3908: }
3909: if (display_number >= MAX_DISPLAYS) {
3910: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3911: return -1;
1.25 markus 3912: }
3913: /* Start listening for connections on the socket. */
1.35 markus 3914: for (n = 0; n < num_socks; n++) {
3915: sock = socks[n];
1.199 markus 3916: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3917: error("listen: %.100s", strerror(errno));
3918: close(sock);
1.141 stevesk 3919: return -1;
1.35 markus 3920: }
1.25 markus 3921: }
1.35 markus 3922:
3923: /* Allocate a channel for each socket. */
1.242 djm 3924: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3925: for (n = 0; n < num_socks; n++) {
3926: sock = socks[n];
1.149 markus 3927: nc = channel_new("x11 listener",
1.51 markus 3928: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3929: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3930: 0, "X11 inet listener", 1);
1.167 markus 3931: nc->single_connection = single_connection;
1.224 markus 3932: (*chanids)[n] = nc->self;
1.35 markus 3933: }
1.224 markus 3934: (*chanids)[n] = -1;
1.1 deraadt 3935:
1.141 stevesk 3936: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3937: *display_numberp = display_number;
3938: return (0);
1.1 deraadt 3939: }
3940:
1.127 itojun 3941: static int
1.77 markus 3942: connect_local_xsocket(u_int dnr)
1.1 deraadt 3943: {
1.25 markus 3944: int sock;
3945: struct sockaddr_un addr;
3946:
1.147 stevesk 3947: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3948: if (sock < 0)
3949: error("socket: %.100s", strerror(errno));
3950: memset(&addr, 0, sizeof(addr));
3951: addr.sun_family = AF_UNIX;
3952: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3953: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3954: return sock;
3955: close(sock);
1.25 markus 3956: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3957: return -1;
1.1 deraadt 3958: }
3959:
1.51 markus 3960: int
3961: x11_connect_display(void)
1.1 deraadt 3962: {
1.248 deraadt 3963: u_int display_number;
1.25 markus 3964: const char *display;
1.51 markus 3965: char buf[1024], *cp;
1.35 markus 3966: struct addrinfo hints, *ai, *aitop;
3967: char strport[NI_MAXSERV];
1.248 deraadt 3968: int gaierr, sock = 0;
1.25 markus 3969:
3970: /* Try to open a socket for the local X server. */
3971: display = getenv("DISPLAY");
3972: if (!display) {
3973: error("DISPLAY not set.");
1.51 markus 3974: return -1;
1.25 markus 3975: }
1.27 markus 3976: /*
3977: * Now we decode the value of the DISPLAY variable and make a
3978: * connection to the real X server.
3979: */
3980:
3981: /*
3982: * Check if it is a unix domain socket. Unix domain displays are in
3983: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3984: */
1.25 markus 3985: if (strncmp(display, "unix:", 5) == 0 ||
3986: display[0] == ':') {
3987: /* Connect to the unix domain socket. */
1.248 deraadt 3988: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3989: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3990: display);
1.51 markus 3991: return -1;
1.25 markus 3992: }
3993: /* Create a socket. */
3994: sock = connect_local_xsocket(display_number);
3995: if (sock < 0)
1.51 markus 3996: return -1;
1.25 markus 3997:
3998: /* OK, we now have a connection to the display. */
1.51 markus 3999: return sock;
1.25 markus 4000: }
1.27 markus 4001: /*
4002: * Connect to an inet socket. The DISPLAY value is supposedly
4003: * hostname:d[.s], where hostname may also be numeric IP address.
4004: */
1.145 stevesk 4005: strlcpy(buf, display, sizeof(buf));
1.25 markus 4006: cp = strchr(buf, ':');
4007: if (!cp) {
4008: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4009: return -1;
1.25 markus 4010: }
4011: *cp = 0;
1.27 markus 4012: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 4013: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4014: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4015: display);
1.51 markus 4016: return -1;
1.25 markus 4017: }
1.35 markus 4018:
4019: /* Look up the host address */
4020: memset(&hints, 0, sizeof(hints));
4021: hints.ai_family = IPv4or6;
4022: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4023: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4024: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4025: error("%.100s: unknown host. (%s)", buf,
4026: ssh_gai_strerror(gaierr));
1.51 markus 4027: return -1;
1.25 markus 4028: }
1.35 markus 4029: for (ai = aitop; ai; ai = ai->ai_next) {
4030: /* Create a socket. */
1.300 dtucker 4031: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4032: if (sock < 0) {
1.194 markus 4033: debug2("socket: %.100s", strerror(errno));
1.41 markus 4034: continue;
4035: }
4036: /* Connect it to the display. */
4037: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4038: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4039: 6000 + display_number, strerror(errno));
4040: close(sock);
4041: continue;
4042: }
4043: /* Success */
4044: break;
1.35 markus 4045: }
4046: freeaddrinfo(aitop);
4047: if (!ai) {
1.248 deraadt 4048: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 4049: strerror(errno));
1.51 markus 4050: return -1;
1.25 markus 4051: }
1.162 stevesk 4052: set_nodelay(sock);
1.51 markus 4053: return sock;
4054: }
4055:
4056: /*
1.27 markus 4057: * Requests forwarding of X11 connections, generates fake authentication
4058: * data, and enables authentication spoofing.
1.121 markus 4059: * This should be called in the client only.
1.27 markus 4060: */
1.49 markus 4061: void
1.215 djm 4062: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.311 djm 4063: const char *proto, const char *data, int want_reply)
1.1 deraadt 4064: {
1.77 markus 4065: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4066: u_int i, value;
1.25 markus 4067: char *new_data;
4068: int screen_number;
4069: const char *cp;
4070:
1.220 markus 4071: if (x11_saved_display == NULL)
4072: x11_saved_display = xstrdup(disp);
4073: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 4074: error("x11_request_forwarding_with_spoofing: different "
4075: "$DISPLAY already forwarded");
4076: return;
4077: }
4078:
1.266 djm 4079: cp = strchr(disp, ':');
1.25 markus 4080: if (cp)
4081: cp = strchr(cp, '.');
4082: if (cp)
1.245 deraadt 4083: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4084: else
4085: screen_number = 0;
4086:
1.219 djm 4087: if (x11_saved_proto == NULL) {
4088: /* Save protocol name. */
4089: x11_saved_proto = xstrdup(proto);
1.353 natano 4090:
4091: /* Extract real authentication data. */
1.219 djm 4092: x11_saved_data = xmalloc(data_len);
4093: for (i = 0; i < data_len; i++) {
4094: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4095: fatal("x11_request_forwarding: bad "
4096: "authentication data: %.100s", data);
4097: x11_saved_data[i] = value;
4098: }
4099: x11_saved_data_len = data_len;
1.353 natano 4100:
4101: /* Generate fake data of the same length. */
4102: x11_fake_data = xmalloc(data_len);
4103: arc4random_buf(x11_fake_data, data_len);
1.219 djm 4104: x11_fake_data_len = data_len;
1.25 markus 4105: }
4106:
4107: /* Convert the fake data into hex. */
1.219 djm 4108: new_data = tohex(x11_fake_data, data_len);
1.25 markus 4109:
4110: /* Send the request packet. */
1.358 djm 4111: channel_request_start(client_session_id, "x11-req", want_reply);
4112: packet_put_char(0); /* XXX bool single connection */
1.51 markus 4113: packet_put_cstring(proto);
4114: packet_put_cstring(new_data);
1.25 markus 4115: packet_put_int(screen_number);
4116: packet_send();
4117: packet_write_wait();
1.321 djm 4118: free(new_data);
1.1 deraadt 4119: }
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