Annotation of src/usr.bin/ssh/channels.c, Revision 1.361
1.361 ! markus 1: /* $OpenBSD: channels.c,v 1.360 2017/05/26 19:34:12 markus 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: if (c->sock != -1)
473: shutdown(c->sock, SHUT_RDWR);
474: channel_close_fds(c);
475: buffer_free(&c->input);
476: buffer_free(&c->output);
477: buffer_free(&c->extended);
1.321 djm 478: free(c->remote_name);
479: c->remote_name = NULL;
480: free(c->path);
481: c->path = NULL;
482: free(c->listening_addr);
483: c->listening_addr = NULL;
1.275 djm 484: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
485: if (cc->abandon_cb != NULL)
486: cc->abandon_cb(c, cc->ctx);
487: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 488: explicit_bzero(cc, sizeof(*cc));
1.321 djm 489: free(cc);
1.275 djm 490: }
1.280 djm 491: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
492: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 493: channels[c->self] = NULL;
1.321 djm 494: free(c);
1.121 markus 495: }
496:
497: void
1.126 markus 498: channel_free_all(void)
1.121 markus 499: {
1.209 avsm 500: u_int i;
1.121 markus 501:
1.126 markus 502: for (i = 0; i < channels_alloc; i++)
503: if (channels[i] != NULL)
504: channel_free(channels[i]);
1.131 markus 505: }
506:
1.121 markus 507: /*
508: * Closes the sockets/fds of all channels. This is used to close extra file
509: * descriptors after a fork.
510: */
511: void
1.142 itojun 512: channel_close_all(void)
1.121 markus 513: {
1.209 avsm 514: u_int i;
1.121 markus 515:
516: for (i = 0; i < channels_alloc; i++)
517: if (channels[i] != NULL)
518: channel_close_fds(channels[i]);
519: }
520:
521: /*
1.131 markus 522: * Stop listening to channels.
523: */
524: void
525: channel_stop_listening(void)
526: {
1.209 avsm 527: u_int i;
1.131 markus 528: Channel *c;
529:
530: for (i = 0; i < channels_alloc; i++) {
531: c = channels[i];
532: if (c != NULL) {
533: switch (c->type) {
534: case SSH_CHANNEL_AUTH_SOCKET:
535: case SSH_CHANNEL_PORT_LISTENER:
536: case SSH_CHANNEL_RPORT_LISTENER:
537: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 538: case SSH_CHANNEL_UNIX_LISTENER:
539: case SSH_CHANNEL_RUNIX_LISTENER:
1.132 markus 540: channel_close_fd(&c->sock);
1.131 markus 541: channel_free(c);
542: break;
543: }
544: }
545: }
546: }
547:
548: /*
1.121 markus 549: * Returns true if no channel has too much buffered data, and false if one or
550: * more channel is overfull.
551: */
552: int
1.142 itojun 553: channel_not_very_much_buffered_data(void)
1.121 markus 554: {
555: u_int i;
556: Channel *c;
557:
558: for (i = 0; i < channels_alloc; i++) {
559: c = channels[i];
560: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
561: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 562: debug2("channel %d: big output buffer %u > %u",
1.136 markus 563: c->self, buffer_len(&c->output),
564: packet_get_maxsize());
1.121 markus 565: return 0;
566: }
567: }
568: }
569: return 1;
570: }
571:
572: /* Returns true if any channel is still open. */
573: int
1.142 itojun 574: channel_still_open(void)
1.121 markus 575: {
1.209 avsm 576: u_int i;
1.121 markus 577: Channel *c;
578:
579: for (i = 0; i < channels_alloc; i++) {
580: c = channels[i];
581: if (c == NULL)
582: continue;
583: switch (c->type) {
584: case SSH_CHANNEL_X11_LISTENER:
585: case SSH_CHANNEL_PORT_LISTENER:
586: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 587: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 588: case SSH_CHANNEL_CLOSED:
589: case SSH_CHANNEL_AUTH_SOCKET:
590: case SSH_CHANNEL_DYNAMIC:
591: case SSH_CHANNEL_CONNECTING:
592: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 593: case SSH_CHANNEL_ABANDONED:
1.336 millert 594: case SSH_CHANNEL_UNIX_LISTENER:
595: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 596: continue;
597: case SSH_CHANNEL_LARVAL:
598: continue;
599: case SSH_CHANNEL_OPENING:
600: case SSH_CHANNEL_OPEN:
601: case SSH_CHANNEL_X11_OPEN:
1.302 djm 602: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 603: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 604: return 1;
605: default:
1.358 djm 606: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 607: /* NOTREACHED */
608: }
609: }
610: return 0;
611: }
612:
613: /* Returns the id of an open channel suitable for keepaliving */
614: int
1.142 itojun 615: channel_find_open(void)
1.121 markus 616: {
1.209 avsm 617: u_int i;
1.121 markus 618: Channel *c;
619:
620: for (i = 0; i < channels_alloc; i++) {
621: c = channels[i];
1.206 djm 622: if (c == NULL || c->remote_id < 0)
1.121 markus 623: continue;
624: switch (c->type) {
625: case SSH_CHANNEL_CLOSED:
626: case SSH_CHANNEL_DYNAMIC:
627: case SSH_CHANNEL_X11_LISTENER:
628: case SSH_CHANNEL_PORT_LISTENER:
629: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 630: case SSH_CHANNEL_MUX_LISTENER:
631: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 632: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 633: case SSH_CHANNEL_OPENING:
634: case SSH_CHANNEL_CONNECTING:
635: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 636: case SSH_CHANNEL_ABANDONED:
1.336 millert 637: case SSH_CHANNEL_UNIX_LISTENER:
638: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 639: continue;
640: case SSH_CHANNEL_LARVAL:
641: case SSH_CHANNEL_AUTH_SOCKET:
642: case SSH_CHANNEL_OPEN:
643: case SSH_CHANNEL_X11_OPEN:
644: return i;
645: default:
1.358 djm 646: fatal("%s: bad channel type %d", __func__, c->type);
1.121 markus 647: /* NOTREACHED */
648: }
649: }
650: return -1;
651: }
652:
653: /*
654: * Returns a message describing the currently open forwarded connections,
655: * suitable for sending to the client. The message contains crlf pairs for
656: * newlines.
657: */
658: char *
1.142 itojun 659: channel_open_message(void)
1.121 markus 660: {
661: Buffer buffer;
662: Channel *c;
663: char buf[1024], *cp;
1.209 avsm 664: u_int i;
1.121 markus 665:
666: buffer_init(&buffer);
667: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
668: buffer_append(&buffer, buf, strlen(buf));
669: for (i = 0; i < channels_alloc; i++) {
670: c = channels[i];
671: if (c == NULL)
672: continue;
673: switch (c->type) {
674: case SSH_CHANNEL_X11_LISTENER:
675: case SSH_CHANNEL_PORT_LISTENER:
676: case SSH_CHANNEL_RPORT_LISTENER:
677: case SSH_CHANNEL_CLOSED:
678: case SSH_CHANNEL_AUTH_SOCKET:
679: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 680: case SSH_CHANNEL_ABANDONED:
1.302 djm 681: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 682: case SSH_CHANNEL_UNIX_LISTENER:
683: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 684: continue;
685: case SSH_CHANNEL_LARVAL:
686: case SSH_CHANNEL_OPENING:
687: case SSH_CHANNEL_CONNECTING:
688: case SSH_CHANNEL_DYNAMIC:
689: case SSH_CHANNEL_OPEN:
690: case SSH_CHANNEL_X11_OPEN:
1.354 markus 691: case SSH_CHANNEL_MUX_PROXY:
692: case SSH_CHANNEL_MUX_CLIENT:
1.204 djm 693: snprintf(buf, sizeof buf,
1.348 djm 694: " #%d %.300s (t%d r%d i%u/%d o%u/%d fd %d/%d cc %d)\r\n",
1.121 markus 695: c->self, c->remote_name,
696: c->type, c->remote_id,
697: c->istate, buffer_len(&c->input),
698: c->ostate, buffer_len(&c->output),
1.302 djm 699: c->rfd, c->wfd, c->ctl_chan);
1.121 markus 700: buffer_append(&buffer, buf, strlen(buf));
701: continue;
702: default:
703: fatal("channel_open_message: bad channel type %d", c->type);
704: /* NOTREACHED */
705: }
706: }
707: buffer_append(&buffer, "\0", 1);
1.337 djm 708: cp = xstrdup((char *)buffer_ptr(&buffer));
1.121 markus 709: buffer_free(&buffer);
710: return cp;
711: }
712:
713: void
714: channel_send_open(int id)
715: {
716: Channel *c = channel_lookup(id);
1.180 deraadt 717:
1.121 markus 718: if (c == NULL) {
1.188 itojun 719: logit("channel_send_open: %d: bad id", id);
1.121 markus 720: return;
721: }
1.184 markus 722: debug2("channel %d: send open", id);
1.121 markus 723: packet_start(SSH2_MSG_CHANNEL_OPEN);
724: packet_put_cstring(c->ctype);
725: packet_put_int(c->self);
726: packet_put_int(c->local_window);
727: packet_put_int(c->local_maxpacket);
728: packet_send();
729: }
730:
731: void
1.184 markus 732: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 733: {
1.184 markus 734: Channel *c = channel_lookup(id);
1.180 deraadt 735:
1.121 markus 736: if (c == NULL) {
1.188 itojun 737: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 738: return;
739: }
1.204 djm 740: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 741: packet_start(SSH2_MSG_CHANNEL_REQUEST);
742: packet_put_int(c->remote_id);
743: packet_put_cstring(service);
744: packet_put_char(wantconfirm);
745: }
1.241 deraadt 746:
1.121 markus 747: void
1.275 djm 748: channel_register_status_confirm(int id, channel_confirm_cb *cb,
749: channel_confirm_abandon_cb *abandon_cb, void *ctx)
750: {
751: struct channel_confirm *cc;
752: Channel *c;
753:
754: if ((c = channel_lookup(id)) == NULL)
755: fatal("channel_register_expect: %d: bad id", id);
756:
1.327 djm 757: cc = xcalloc(1, sizeof(*cc));
1.275 djm 758: cc->cb = cb;
759: cc->abandon_cb = abandon_cb;
760: cc->ctx = ctx;
761: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
762: }
763:
764: void
1.304 djm 765: channel_register_open_confirm(int id, channel_open_fn *fn, void *ctx)
1.121 markus 766: {
767: Channel *c = channel_lookup(id);
1.180 deraadt 768:
1.121 markus 769: if (c == NULL) {
1.287 stevesk 770: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 771: return;
772: }
1.275 djm 773: c->open_confirm = fn;
774: c->open_confirm_ctx = ctx;
1.121 markus 775: }
1.241 deraadt 776:
1.121 markus 777: void
1.225 djm 778: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 779: {
1.229 markus 780: Channel *c = channel_by_id(id);
1.180 deraadt 781:
1.121 markus 782: if (c == NULL) {
1.188 itojun 783: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 784: return;
785: }
1.131 markus 786: c->detach_user = fn;
1.225 djm 787: c->detach_close = do_close;
1.121 markus 788: }
1.241 deraadt 789:
1.121 markus 790: void
791: channel_cancel_cleanup(int id)
792: {
1.229 markus 793: Channel *c = channel_by_id(id);
1.180 deraadt 794:
1.121 markus 795: if (c == NULL) {
1.188 itojun 796: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 797: return;
1.52 markus 798: }
1.131 markus 799: c->detach_user = NULL;
1.225 djm 800: c->detach_close = 0;
1.121 markus 801: }
1.241 deraadt 802:
1.121 markus 803: void
1.231 reyk 804: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 805: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 806: {
807: Channel *c = channel_lookup(id);
1.180 deraadt 808:
1.121 markus 809: if (c == NULL) {
1.188 itojun 810: logit("channel_register_filter: %d: bad id", id);
1.121 markus 811: return;
1.52 markus 812: }
1.231 reyk 813: c->input_filter = ifn;
814: c->output_filter = ofn;
1.279 djm 815: c->filter_ctx = ctx;
1.280 djm 816: c->filter_cleanup = cfn;
1.52 markus 817: }
818:
1.49 markus 819: void
1.121 markus 820: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 821: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 822: {
1.121 markus 823: Channel *c = channel_lookup(id);
1.180 deraadt 824:
1.121 markus 825: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
826: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 827: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 828: c->type = SSH_CHANNEL_OPEN;
1.168 markus 829: c->local_window = c->local_window_max = window_max;
1.121 markus 830: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
831: packet_put_int(c->remote_id);
832: packet_put_int(c->local_window);
833: packet_send();
1.1 deraadt 834: }
835:
1.27 markus 836: /*
1.41 markus 837: * 'channel_pre*' are called just before select() to add any bits relevant to
838: * channels in the select bitmasks.
839: */
840: /*
841: * 'channel_post*': perform any appropriate operations for channels which
842: * have events pending.
1.27 markus 843: */
1.237 deraadt 844: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 845: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
846: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
847:
1.259 stevesk 848: /* ARGSUSED */
1.127 itojun 849: static void
1.237 deraadt 850: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 851: {
852: FD_SET(c->sock, readset);
853: }
854:
1.259 stevesk 855: /* ARGSUSED */
1.127 itojun 856: static void
1.237 deraadt 857: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 858: {
859: debug3("channel %d: waiting for connection", c->self);
860: FD_SET(c->sock, writeset);
861: }
862:
1.127 itojun 863: static void
1.237 deraadt 864: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 865: {
1.44 markus 866: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 867: c->remote_window > 0 &&
868: buffer_len(&c->input) < c->remote_window &&
1.250 djm 869: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 870: FD_SET(c->rfd, readset);
871: if (c->ostate == CHAN_OUTPUT_OPEN ||
872: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
873: if (buffer_len(&c->output) > 0) {
874: FD_SET(c->wfd, writeset);
875: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 876: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 877: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
878: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 879: else
880: chan_obuf_empty(c);
1.44 markus 881: }
882: }
883: /** XXX check close conditions, too */
1.358 djm 884: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
885: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 886: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
887: buffer_len(&c->extended) > 0)
888: FD_SET(c->efd, writeset);
1.306 djm 889: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
890: (c->extended_usage == CHAN_EXTENDED_READ ||
891: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 892: buffer_len(&c->extended) < c->remote_window)
893: FD_SET(c->efd, readset);
894: }
1.204 djm 895: /* XXX: What about efd? races? */
1.44 markus 896: }
897:
1.41 markus 898: /*
899: * This is a special state for X11 authentication spoofing. An opened X11
900: * connection (when authentication spoofing is being done) remains in this
901: * state until the first packet has been completely read. The authentication
902: * data in that packet is then substituted by the real data if it matches the
903: * fake data, and the channel is put into normal mode.
1.51 markus 904: * XXX All this happens at the client side.
1.121 markus 905: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 906: */
1.127 itojun 907: static int
1.121 markus 908: x11_open_helper(Buffer *b)
1.1 deraadt 909: {
1.77 markus 910: u_char *ucp;
911: u_int proto_len, data_len;
1.25 markus 912:
1.347 djm 913: /* Is this being called after the refusal deadline? */
914: if (x11_refuse_time != 0 && (u_int)monotime() >= x11_refuse_time) {
915: verbose("Rejected X11 connection after ForwardX11Timeout "
916: "expired");
917: return -1;
918: }
919:
1.41 markus 920: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 921: if (buffer_len(b) < 12)
1.41 markus 922: return 0;
923:
924: /* Parse the lengths of variable-length fields. */
1.155 stevesk 925: ucp = buffer_ptr(b);
1.41 markus 926: if (ucp[0] == 0x42) { /* Byte order MSB first. */
927: proto_len = 256 * ucp[6] + ucp[7];
928: data_len = 256 * ucp[8] + ucp[9];
929: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
930: proto_len = ucp[6] + 256 * ucp[7];
931: data_len = ucp[8] + 256 * ucp[9];
932: } else {
1.194 markus 933: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 934: ucp[0]);
1.41 markus 935: return -1;
936: }
937:
938: /* Check if the whole packet is in buffer. */
1.121 markus 939: if (buffer_len(b) <
1.41 markus 940: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
941: return 0;
942:
943: /* Check if authentication protocol matches. */
944: if (proto_len != strlen(x11_saved_proto) ||
945: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 946: debug2("X11 connection uses different authentication protocol.");
1.41 markus 947: return -1;
948: }
949: /* Check if authentication data matches our fake data. */
950: if (data_len != x11_fake_data_len ||
1.308 djm 951: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.41 markus 952: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 953: debug2("X11 auth data does not match fake data.");
1.41 markus 954: return -1;
955: }
956: /* Check fake data length */
957: if (x11_fake_data_len != x11_saved_data_len) {
958: error("X11 fake_data_len %d != saved_data_len %d",
959: x11_fake_data_len, x11_saved_data_len);
960: return -1;
961: }
962: /*
963: * Received authentication protocol and data match
964: * our fake data. Substitute the fake data with real
965: * data.
966: */
967: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
968: x11_saved_data, x11_saved_data_len);
969: return 1;
970: }
971:
1.127 itojun 972: static void
1.237 deraadt 973: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 974: {
1.121 markus 975: int ret = x11_open_helper(&c->output);
1.133 markus 976:
977: /* c->force_drain = 1; */
978:
1.41 markus 979: if (ret == 1) {
980: c->type = SSH_CHANNEL_OPEN;
1.157 markus 981: channel_pre_open(c, readset, writeset);
1.41 markus 982: } else if (ret == -1) {
1.188 itojun 983: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 984: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 985: chan_read_failed(c);
986: buffer_clear(&c->input);
987: chan_ibuf_empty(c);
988: buffer_clear(&c->output);
1.358 djm 989: chan_write_failed(c);
1.194 markus 990: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 991: }
992: }
1.25 markus 993:
1.302 djm 994: static void
995: channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
996: {
1.304 djm 997: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.302 djm 998: buffer_check_alloc(&c->input, CHAN_RBUF))
999: FD_SET(c->rfd, readset);
1000: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1001: /* clear buffer immediately (discard any partial packet) */
1002: buffer_clear(&c->input);
1003: chan_ibuf_empty(c);
1004: /* Start output drain. XXX just kill chan? */
1005: chan_rcvd_oclose(c);
1006: }
1007: if (c->ostate == CHAN_OUTPUT_OPEN ||
1008: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1009: if (buffer_len(&c->output) > 0)
1010: FD_SET(c->wfd, writeset);
1011: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1012: chan_obuf_empty(c);
1013: }
1014: }
1015:
1.104 markus 1016: /* try to decode a socks4 header */
1.259 stevesk 1017: /* ARGSUSED */
1.127 itojun 1018: static int
1.237 deraadt 1019: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 1020: {
1.181 markus 1021: char *p, *host;
1.292 djm 1022: u_int len, have, i, found, need;
1.148 deraadt 1023: char username[256];
1.103 markus 1024: struct {
1025: u_int8_t version;
1026: u_int8_t command;
1027: u_int16_t dest_port;
1.104 markus 1028: struct in_addr dest_addr;
1.103 markus 1029: } s4_req, s4_rsp;
1030:
1.104 markus 1031: debug2("channel %d: decode socks4", c->self);
1.109 markus 1032:
1033: have = buffer_len(&c->input);
1034: len = sizeof(s4_req);
1035: if (have < len)
1036: return 0;
1.337 djm 1037: p = (char *)buffer_ptr(&c->input);
1.292 djm 1038:
1039: need = 1;
1040: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1041: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1042: debug2("channel %d: socks4a request", c->self);
1043: /* ... and needs an extra string (the hostname) */
1044: need = 2;
1045: }
1046: /* Check for terminating NUL on the string(s) */
1.109 markus 1047: for (found = 0, i = len; i < have; i++) {
1048: if (p[i] == '\0') {
1.292 djm 1049: found++;
1050: if (found == need)
1051: break;
1.109 markus 1052: }
1053: if (i > 1024) {
1054: /* the peer is probably sending garbage */
1055: debug("channel %d: decode socks4: too long",
1056: c->self);
1057: return -1;
1058: }
1059: }
1.292 djm 1060: if (found < need)
1.109 markus 1061: return 0;
1.103 markus 1062: buffer_get(&c->input, (char *)&s4_req.version, 1);
1063: buffer_get(&c->input, (char *)&s4_req.command, 1);
1064: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1065: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1066: have = buffer_len(&c->input);
1.337 djm 1067: p = (char *)buffer_ptr(&c->input);
1.331 djm 1068: if (memchr(p, '\0', have) == NULL)
1069: fatal("channel %d: decode socks4: user not nul terminated",
1070: c->self);
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);
1.292 djm 1088: len = strlen(p);
1089: debug2("channel %d: decode socks4a: host %s/%d",
1090: c->self, p, len);
1091: len++; /* trailing '\0' */
1092: if (len > have)
1093: fatal("channel %d: decode socks4a: len %d > have %d",
1094: c->self, len, have);
1.293 djm 1095: if (len > NI_MAXHOST) {
1.292 djm 1096: error("channel %d: hostname \"%.100s\" too long",
1097: c->self, p);
1098: return -1;
1099: }
1.293 djm 1100: c->path = xstrdup(p);
1.292 djm 1101: buffer_consume(&c->input, len);
1102: }
1.103 markus 1103: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1104:
1.194 markus 1105: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1106: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1107:
1.104 markus 1108: if (s4_req.command != 1) {
1.292 djm 1109: debug("channel %d: cannot handle: %s cn %d",
1110: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1111: return -1;
1.103 markus 1112: }
1.104 markus 1113: s4_rsp.version = 0; /* vn: 0 for reply */
1114: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1115: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1116: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1117: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1118: return 1;
1119: }
1120:
1.193 markus 1121: /* try to decode a socks5 header */
1122: #define SSH_SOCKS5_AUTHDONE 0x1000
1123: #define SSH_SOCKS5_NOAUTH 0x00
1124: #define SSH_SOCKS5_IPV4 0x01
1125: #define SSH_SOCKS5_DOMAIN 0x03
1126: #define SSH_SOCKS5_IPV6 0x04
1127: #define SSH_SOCKS5_CONNECT 0x01
1128: #define SSH_SOCKS5_SUCCESS 0x00
1129:
1.259 stevesk 1130: /* ARGSUSED */
1.193 markus 1131: static int
1.237 deraadt 1132: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1133: {
1134: struct {
1135: u_int8_t version;
1136: u_int8_t command;
1137: u_int8_t reserved;
1138: u_int8_t atyp;
1139: } s5_req, s5_rsp;
1140: u_int16_t dest_port;
1.324 djm 1141: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1142: u_char *p;
1.252 djm 1143: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1144:
1145: debug2("channel %d: decode socks5", c->self);
1146: p = buffer_ptr(&c->input);
1147: if (p[0] != 0x05)
1148: return -1;
1149: have = buffer_len(&c->input);
1150: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1151: /* format: ver | nmethods | methods */
1.198 djm 1152: if (have < 2)
1.193 markus 1153: return 0;
1154: nmethods = p[1];
1155: if (have < nmethods + 2)
1156: return 0;
1157: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1158: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1159: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1160: found = 1;
1161: break;
1162: }
1163: }
1164: if (!found) {
1165: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1166: c->self);
1167: return -1;
1168: }
1169: buffer_consume(&c->input, nmethods + 2);
1170: buffer_put_char(&c->output, 0x05); /* version */
1171: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1172: FD_SET(c->sock, writeset);
1173: c->flags |= SSH_SOCKS5_AUTHDONE;
1174: debug2("channel %d: socks5 auth done", c->self);
1175: return 0; /* need more */
1176: }
1177: debug2("channel %d: socks5 post auth", c->self);
1178: if (have < sizeof(s5_req)+1)
1179: return 0; /* need more */
1.247 deraadt 1180: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1181: if (s5_req.version != 0x05 ||
1182: s5_req.command != SSH_SOCKS5_CONNECT ||
1183: s5_req.reserved != 0x00) {
1.194 markus 1184: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1185: return -1;
1186: }
1.213 deraadt 1187: switch (s5_req.atyp){
1.193 markus 1188: case SSH_SOCKS5_IPV4:
1189: addrlen = 4;
1190: af = AF_INET;
1191: break;
1192: case SSH_SOCKS5_DOMAIN:
1193: addrlen = p[sizeof(s5_req)];
1194: af = -1;
1195: break;
1196: case SSH_SOCKS5_IPV6:
1197: addrlen = 16;
1198: af = AF_INET6;
1199: break;
1200: default:
1.194 markus 1201: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1202: return -1;
1203: }
1.252 djm 1204: need = sizeof(s5_req) + addrlen + 2;
1205: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1206: need++;
1207: if (have < need)
1.193 markus 1208: return 0;
1209: buffer_consume(&c->input, sizeof(s5_req));
1210: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1211: buffer_consume(&c->input, 1); /* host string length */
1.324 djm 1212: buffer_get(&c->input, &dest_addr, addrlen);
1.193 markus 1213: buffer_get(&c->input, (char *)&dest_port, 2);
1214: dest_addr[addrlen] = '\0';
1.321 djm 1215: free(c->path);
1216: c->path = NULL;
1.293 djm 1217: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1218: if (addrlen >= NI_MAXHOST) {
1.293 djm 1219: error("channel %d: dynamic request: socks5 hostname "
1220: "\"%.100s\" too long", c->self, dest_addr);
1221: return -1;
1222: }
1223: c->path = xstrdup(dest_addr);
1224: } else {
1225: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1226: return -1;
1227: c->path = xstrdup(ntop);
1228: }
1.193 markus 1229: c->host_port = ntohs(dest_port);
1.198 djm 1230:
1.194 markus 1231: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1232: c->self, c->path, c->host_port, s5_req.command);
1233:
1234: s5_rsp.version = 0x05;
1235: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1236: s5_rsp.reserved = 0; /* ignored */
1237: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1238: dest_port = 0; /* ignored */
1239:
1.246 deraadt 1240: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1.325 djm 1241: buffer_put_int(&c->output, ntohl(INADDR_ANY)); /* bind address */
1.246 deraadt 1242: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1243: return 1;
1.301 dtucker 1244: }
1245:
1246: Channel *
1.302 djm 1247: channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
1248: int in, int out)
1.301 dtucker 1249: {
1250: Channel *c;
1251:
1252: debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
1253: port_to_connect);
1254:
1255: c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
1256: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1257: 0, "stdio-forward", /*nonblock*/0);
1258:
1259: c->path = xstrdup(host_to_connect);
1260: c->host_port = port_to_connect;
1261: c->listening_port = 0;
1262: c->force_drain = 1;
1263:
1264: channel_register_fds(c, in, out, -1, 0, 1, 0);
1265: port_open_helper(c, "direct-tcpip");
1266:
1267: return c;
1.193 markus 1268: }
1269:
1.104 markus 1270: /* dynamic port forwarding */
1.127 itojun 1271: static void
1.237 deraadt 1272: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1273: {
1274: u_char *p;
1.217 djm 1275: u_int have;
1276: int ret;
1.103 markus 1277:
1.104 markus 1278: have = buffer_len(&c->input);
1279: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1280: /* buffer_dump(&c->input); */
1.104 markus 1281: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1282: if (have < 3) {
1.104 markus 1283: /* need more */
1284: FD_SET(c->sock, readset);
1285: return;
1286: }
1287: /* try to guess the protocol */
1288: p = buffer_ptr(&c->input);
1289: switch (p[0]) {
1290: case 0x04:
1291: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1292: break;
1293: case 0x05:
1294: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1295: break;
1296: default:
1297: ret = -1;
1298: break;
1299: }
1300: if (ret < 0) {
1.113 markus 1301: chan_mark_dead(c);
1.104 markus 1302: } else if (ret == 0) {
1303: debug2("channel %d: pre_dynamic: need more", c->self);
1304: /* need more */
1305: FD_SET(c->sock, readset);
1306: } else {
1307: /* switch to the next state */
1308: c->type = SSH_CHANNEL_OPENING;
1309: port_open_helper(c, "direct-tcpip");
1310: }
1.103 markus 1311: }
1312:
1.41 markus 1313: /* This is our fake X11 server socket. */
1.259 stevesk 1314: /* ARGSUSED */
1.127 itojun 1315: static void
1.237 deraadt 1316: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1317: {
1.113 markus 1318: Channel *nc;
1.285 djm 1319: struct sockaddr_storage addr;
1.320 markus 1320: int newsock, oerrno;
1.41 markus 1321: socklen_t addrlen;
1.85 markus 1322: char buf[16384], *remote_ipaddr;
1.51 markus 1323: int remote_port;
1.25 markus 1324:
1.41 markus 1325: if (FD_ISSET(c->sock, readset)) {
1326: debug("X11 connection requested.");
1327: addrlen = sizeof(addr);
1.285 djm 1328: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1329: if (c->single_connection) {
1.320 markus 1330: oerrno = errno;
1.194 markus 1331: debug2("single_connection: closing X11 listener.");
1.149 markus 1332: channel_close_fd(&c->sock);
1333: chan_mark_dead(c);
1.320 markus 1334: errno = oerrno;
1.149 markus 1335: }
1.41 markus 1336: if (newsock < 0) {
1.320 markus 1337: if (errno != EINTR && errno != EWOULDBLOCK &&
1338: errno != ECONNABORTED)
1339: error("accept: %.100s", strerror(errno));
1.317 djm 1340: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1341: c->notbefore = monotime() + 1;
1.41 markus 1342: return;
1343: }
1.162 stevesk 1344: set_nodelay(newsock);
1.85 markus 1345: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1346: remote_port = get_peer_port(newsock);
1.41 markus 1347: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1348: remote_ipaddr, remote_port);
1.51 markus 1349:
1.113 markus 1350: nc = channel_new("accepted x11 socket",
1.51 markus 1351: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1352: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.358 djm 1353: packet_start(SSH2_MSG_CHANNEL_OPEN);
1354: packet_put_cstring("x11");
1355: packet_put_int(nc->self);
1356: packet_put_int(nc->local_window_max);
1357: packet_put_int(nc->local_maxpacket);
1358: /* originator ipaddr and port */
1359: packet_put_cstring(remote_ipaddr);
1360: if (datafellows & SSH_BUG_X11FWD) {
1361: debug2("ssh2 x11 bug compat mode");
1.51 markus 1362: } else {
1.358 djm 1363: packet_put_int(remote_port);
1.51 markus 1364: }
1.358 djm 1365: packet_send();
1.321 djm 1366: free(remote_ipaddr);
1.41 markus 1367: }
1368: }
1.25 markus 1369:
1.127 itojun 1370: static void
1.103 markus 1371: port_open_helper(Channel *c, char *rtype)
1372: {
1373: char buf[1024];
1.328 djm 1374: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1375: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1376: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1377: int remote_port = get_peer_port(c->sock);
1.303 djm 1378:
1379: if (remote_port == -1) {
1380: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1381: free(remote_ipaddr);
1.303 djm 1382: remote_ipaddr = xstrdup("127.0.0.1");
1383: remote_port = 65535;
1384: }
1.103 markus 1385:
1386: snprintf(buf, sizeof buf,
1387: "%s: listening port %d for %.100s port %d, "
1.328 djm 1388: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1389: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1390: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1391:
1.321 djm 1392: free(c->remote_name);
1.103 markus 1393: c->remote_name = xstrdup(buf);
1394:
1.358 djm 1395: packet_start(SSH2_MSG_CHANNEL_OPEN);
1396: packet_put_cstring(rtype);
1397: packet_put_int(c->self);
1398: packet_put_int(c->local_window_max);
1399: packet_put_int(c->local_maxpacket);
1400: if (strcmp(rtype, "direct-tcpip") == 0) {
1401: /* target host, port */
1402: packet_put_cstring(c->path);
1403: packet_put_int(c->host_port);
1404: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1405: /* target path */
1406: packet_put_cstring(c->path);
1407: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1408: /* listen path */
1409: packet_put_cstring(c->path);
1.103 markus 1410: } else {
1.358 djm 1411: /* listen address, port */
1.103 markus 1412: packet_put_cstring(c->path);
1.358 djm 1413: packet_put_int(local_port);
1414: }
1415: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1416: /* reserved for future owner/mode info */
1417: packet_put_cstring("");
1418: } else {
1419: /* originator host and port */
1420: packet_put_cstring(remote_ipaddr);
1421: packet_put_int((u_int)remote_port);
1.103 markus 1422: }
1.358 djm 1423: packet_send();
1.321 djm 1424: free(remote_ipaddr);
1.328 djm 1425: free(local_ipaddr);
1.103 markus 1426: }
1427:
1.226 djm 1428: static void
1429: channel_set_reuseaddr(int fd)
1430: {
1431: int on = 1;
1432:
1433: /*
1434: * Set socket options.
1435: * Allow local port reuse in TIME_WAIT.
1436: */
1437: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1438: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1.347 djm 1439: }
1440:
1441: void
1442: channel_set_x11_refuse_time(u_int refuse_time)
1443: {
1444: x11_refuse_time = refuse_time;
1.226 djm 1445: }
1446:
1.41 markus 1447: /*
1448: * This socket is listening for connections to a forwarded TCP/IP port.
1449: */
1.259 stevesk 1450: /* ARGSUSED */
1.127 itojun 1451: static void
1.237 deraadt 1452: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1453: {
1.103 markus 1454: Channel *nc;
1.285 djm 1455: struct sockaddr_storage addr;
1.113 markus 1456: int newsock, nextstate;
1.41 markus 1457: socklen_t addrlen;
1.103 markus 1458: char *rtype;
1.73 markus 1459:
1.41 markus 1460: if (FD_ISSET(c->sock, readset)) {
1461: debug("Connection to port %d forwarding "
1462: "to %.100s port %d requested.",
1463: c->listening_port, c->path, c->host_port);
1.103 markus 1464:
1.137 markus 1465: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1466: nextstate = SSH_CHANNEL_OPENING;
1467: rtype = "forwarded-tcpip";
1.336 millert 1468: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1469: nextstate = SSH_CHANNEL_OPENING;
1470: rtype = "forwarded-streamlocal@openssh.com";
1471: } else if (c->host_port == PORT_STREAMLOCAL) {
1472: nextstate = SSH_CHANNEL_OPENING;
1473: rtype = "direct-streamlocal@openssh.com";
1474: } else if (c->host_port == 0) {
1475: nextstate = SSH_CHANNEL_DYNAMIC;
1476: rtype = "dynamic-tcpip";
1.137 markus 1477: } else {
1.336 millert 1478: nextstate = SSH_CHANNEL_OPENING;
1479: rtype = "direct-tcpip";
1.137 markus 1480: }
1.103 markus 1481:
1.41 markus 1482: addrlen = sizeof(addr);
1.285 djm 1483: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1484: if (newsock < 0) {
1.320 markus 1485: if (errno != EINTR && errno != EWOULDBLOCK &&
1486: errno != ECONNABORTED)
1487: error("accept: %.100s", strerror(errno));
1.317 djm 1488: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1489: c->notbefore = monotime() + 1;
1.41 markus 1490: return;
1491: }
1.336 millert 1492: if (c->host_port != PORT_STREAMLOCAL)
1493: set_nodelay(newsock);
1.190 markus 1494: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1495: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1496: nc->listening_port = c->listening_port;
1497: nc->host_port = c->host_port;
1.293 djm 1498: if (c->path != NULL)
1499: nc->path = xstrdup(c->path);
1.103 markus 1500:
1.299 markus 1501: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1502: port_open_helper(nc, rtype);
1.41 markus 1503: }
1504: }
1.25 markus 1505:
1.41 markus 1506: /*
1507: * This is the authentication agent socket listening for connections from
1508: * clients.
1509: */
1.259 stevesk 1510: /* ARGSUSED */
1.127 itojun 1511: static void
1.237 deraadt 1512: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1513: {
1.113 markus 1514: Channel *nc;
1515: int newsock;
1.285 djm 1516: struct sockaddr_storage addr;
1.41 markus 1517: socklen_t addrlen;
1.25 markus 1518:
1.41 markus 1519: if (FD_ISSET(c->sock, readset)) {
1520: addrlen = sizeof(addr);
1.285 djm 1521: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1522: if (newsock < 0) {
1.317 djm 1523: error("accept from auth socket: %.100s",
1524: strerror(errno));
1525: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1526: c->notbefore = monotime() + 1;
1.41 markus 1527: return;
1528: }
1.113 markus 1529: nc = channel_new("accepted auth socket",
1.73 markus 1530: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1531: c->local_window_max, c->local_maxpacket,
1.190 markus 1532: 0, "accepted auth socket", 1);
1.358 djm 1533: packet_start(SSH2_MSG_CHANNEL_OPEN);
1534: packet_put_cstring("auth-agent@openssh.com");
1535: packet_put_int(nc->self);
1536: packet_put_int(c->local_window_max);
1537: packet_put_int(c->local_maxpacket);
1.41 markus 1538: packet_send();
1539: }
1540: }
1.25 markus 1541:
1.259 stevesk 1542: /* ARGSUSED */
1.127 itojun 1543: static void
1.237 deraadt 1544: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1545: {
1.276 djm 1546: int err = 0, sock;
1.129 stevesk 1547: socklen_t sz = sizeof(err);
1.114 markus 1548:
1.75 markus 1549: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1550: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1551: err = errno;
1552: error("getsockopt SO_ERROR failed");
1553: }
1554: if (err == 0) {
1.276 djm 1555: debug("channel %d: connected to %s port %d",
1556: c->self, c->connect_ctx.host, c->connect_ctx.port);
1557: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1558: c->type = SSH_CHANNEL_OPEN;
1.358 djm 1559: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1560: packet_put_int(c->remote_id);
1561: packet_put_int(c->self);
1562: packet_put_int(c->local_window);
1563: packet_put_int(c->local_maxpacket);
1.75 markus 1564: } else {
1.276 djm 1565: debug("channel %d: connection failed: %s",
1.114 markus 1566: c->self, strerror(err));
1.276 djm 1567: /* Try next address, if any */
1568: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1569: close(c->sock);
1570: c->sock = c->rfd = c->wfd = sock;
1571: channel_max_fd = channel_find_maxfd();
1572: return;
1573: }
1574: /* Exhausted all addresses */
1575: error("connect_to %.100s port %d: failed.",
1576: c->connect_ctx.host, c->connect_ctx.port);
1577: channel_connect_ctx_free(&c->connect_ctx);
1.358 djm 1578: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1579: packet_put_int(c->remote_id);
1580: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1581: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1582: packet_put_cstring(strerror(err));
1583: packet_put_cstring("");
1.75 markus 1584: }
1.114 markus 1585: chan_mark_dead(c);
1.75 markus 1586: }
1.114 markus 1587: packet_send();
1.75 markus 1588: }
1589: }
1590:
1.259 stevesk 1591: /* ARGSUSED */
1.127 itojun 1592: static int
1.237 deraadt 1593: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1594: {
1.214 markus 1595: char buf[CHAN_RBUF];
1.41 markus 1596: int len;
1.25 markus 1597:
1.118 markus 1598: if (c->rfd != -1 &&
1.41 markus 1599: FD_ISSET(c->rfd, readset)) {
1600: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1601: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1602: return 1;
1.41 markus 1603: if (len <= 0) {
1.194 markus 1604: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1605: c->self, c->rfd, len);
1.104 markus 1606: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1607: debug2("channel %d: not open", c->self);
1.113 markus 1608: chan_mark_dead(c);
1.103 markus 1609: return -1;
1.25 markus 1610: } else {
1.41 markus 1611: chan_read_failed(c);
1.25 markus 1612: }
1.41 markus 1613: return -1;
1614: }
1.143 deraadt 1615: if (c->input_filter != NULL) {
1.66 markus 1616: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1617: debug2("channel %d: filter stops", c->self);
1.65 markus 1618: chan_read_failed(c);
1619: }
1.228 reyk 1620: } else if (c->datagram) {
1621: buffer_put_string(&c->input, buf, len);
1.65 markus 1622: } else {
1623: buffer_append(&c->input, buf, len);
1624: }
1.41 markus 1625: }
1626: return 1;
1627: }
1.241 deraadt 1628:
1.259 stevesk 1629: /* ARGSUSED */
1.127 itojun 1630: static int
1.237 deraadt 1631: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1632: {
1.95 markus 1633: struct termios tio;
1.231 reyk 1634: u_char *data = NULL, *buf;
1.309 djm 1635: u_int dlen, olen = 0;
1.41 markus 1636: int len;
1.25 markus 1637:
1.41 markus 1638: /* Send buffered output data to the socket. */
1.118 markus 1639: if (c->wfd != -1 &&
1.41 markus 1640: FD_ISSET(c->wfd, writeset) &&
1641: buffer_len(&c->output) > 0) {
1.309 djm 1642: olen = buffer_len(&c->output);
1.231 reyk 1643: if (c->output_filter != NULL) {
1644: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1645: debug2("channel %d: filter stops", c->self);
1.232 reyk 1646: if (c->type != SSH_CHANNEL_OPEN)
1647: chan_mark_dead(c);
1648: else
1649: chan_write_failed(c);
1650: return -1;
1.231 reyk 1651: }
1652: } else if (c->datagram) {
1653: buf = data = buffer_get_string(&c->output, &dlen);
1654: } else {
1655: buf = data = buffer_ptr(&c->output);
1656: dlen = buffer_len(&c->output);
1657: }
1658:
1.228 reyk 1659: if (c->datagram) {
1660: /* ignore truncated writes, datagrams might get lost */
1.231 reyk 1661: len = write(c->wfd, buf, dlen);
1.321 djm 1662: free(data);
1.228 reyk 1663: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1664: return 1;
1665: if (len <= 0) {
1666: if (c->type != SSH_CHANNEL_OPEN)
1667: chan_mark_dead(c);
1668: else
1669: chan_write_failed(c);
1670: return -1;
1671: }
1.309 djm 1672: goto out;
1.228 reyk 1673: }
1.231 reyk 1674:
1675: len = write(c->wfd, buf, dlen);
1.53 markus 1676: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1677: return 1;
1.41 markus 1678: if (len <= 0) {
1.104 markus 1679: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1680: debug2("channel %d: not open", c->self);
1.113 markus 1681: chan_mark_dead(c);
1.104 markus 1682: return -1;
1.41 markus 1683: } else {
1684: chan_write_failed(c);
1685: }
1686: return -1;
1.91 markus 1687: }
1.358 djm 1688: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1689: if (tcgetattr(c->wfd, &tio) == 0 &&
1690: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1691: /*
1692: * Simulate echo to reduce the impact of
1.96 markus 1693: * traffic analysis. We need to match the
1.95 markus 1694: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1695: * (4 byte channel id + buf)
1.91 markus 1696: */
1.95 markus 1697: packet_send_ignore(4 + len);
1.91 markus 1698: packet_send();
1699: }
1.25 markus 1700: }
1.41 markus 1701: buffer_consume(&c->output, len);
1.44 markus 1702: }
1.309 djm 1703: out:
1.358 djm 1704: if (olen > 0)
1.309 djm 1705: c->local_consumed += olen - buffer_len(&c->output);
1.44 markus 1706: return 1;
1707: }
1.241 deraadt 1708:
1.127 itojun 1709: static int
1.237 deraadt 1710: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1711: {
1.214 markus 1712: char buf[CHAN_RBUF];
1.44 markus 1713: int len;
1714:
1.45 markus 1715: /** XXX handle drain efd, too */
1.44 markus 1716: if (c->efd != -1) {
1717: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1718: FD_ISSET(c->efd, writeset) &&
1719: buffer_len(&c->extended) > 0) {
1720: len = write(c->efd, buffer_ptr(&c->extended),
1721: buffer_len(&c->extended));
1.70 markus 1722: debug2("channel %d: written %d to efd %d",
1.44 markus 1723: c->self, len, c->efd);
1.93 markus 1724: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1725: return 1;
1726: if (len <= 0) {
1727: debug2("channel %d: closing write-efd %d",
1728: c->self, c->efd);
1.132 markus 1729: channel_close_fd(&c->efd);
1.93 markus 1730: } else {
1.44 markus 1731: buffer_consume(&c->extended, len);
1732: c->local_consumed += len;
1733: }
1.306 djm 1734: } else if (c->efd != -1 &&
1735: (c->extended_usage == CHAN_EXTENDED_READ ||
1736: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 1737: FD_ISSET(c->efd, readset)) {
1738: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1739: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1740: c->self, len, c->efd);
1.93 markus 1741: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1742: return 1;
1743: if (len <= 0) {
1744: debug2("channel %d: closing read-efd %d",
1.45 markus 1745: c->self, c->efd);
1.132 markus 1746: channel_close_fd(&c->efd);
1.93 markus 1747: } else {
1.306 djm 1748: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
1749: debug3("channel %d: discard efd",
1750: c->self);
1751: } else
1752: buffer_append(&c->extended, buf, len);
1.93 markus 1753: }
1.44 markus 1754: }
1755: }
1756: return 1;
1757: }
1.241 deraadt 1758:
1.259 stevesk 1759: /* ARGSUSED */
1.127 itojun 1760: static int
1.93 markus 1761: channel_check_window(Channel *c)
1.44 markus 1762: {
1.104 markus 1763: if (c->type == SSH_CHANNEL_OPEN &&
1764: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1765: ((c->local_window_max - c->local_window >
1.269 markus 1766: c->local_maxpacket*3) ||
1767: c->local_window < c->local_window_max/2) &&
1.44 markus 1768: c->local_consumed > 0) {
1769: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1770: packet_put_int(c->remote_id);
1771: packet_put_int(c->local_consumed);
1772: packet_send();
1.70 markus 1773: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1774: c->self, c->local_window,
1775: c->local_consumed);
1776: c->local_window += c->local_consumed;
1777: c->local_consumed = 0;
1.1 deraadt 1778: }
1.41 markus 1779: return 1;
1.1 deraadt 1780: }
1781:
1.127 itojun 1782: static void
1.237 deraadt 1783: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1784: {
1785: channel_handle_rfd(c, readset, writeset);
1786: channel_handle_wfd(c, readset, writeset);
1.44 markus 1787: channel_handle_efd(c, readset, writeset);
1.93 markus 1788: channel_check_window(c);
1.44 markus 1789: }
1790:
1.302 djm 1791: static u_int
1792: read_mux(Channel *c, u_int need)
1793: {
1794: char buf[CHAN_RBUF];
1795: int len;
1796: u_int rlen;
1797:
1798: if (buffer_len(&c->input) < need) {
1799: rlen = need - buffer_len(&c->input);
1.352 deraadt 1800: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 1801: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1802: return buffer_len(&c->input);
1.302 djm 1803: if (len <= 0) {
1.349 naddy 1804: debug2("channel %d: ctl read<=0 rfd %d len %d",
1805: c->self, c->rfd, len);
1806: chan_read_failed(c);
1807: return 0;
1.302 djm 1808: } else
1809: buffer_append(&c->input, buf, len);
1810: }
1811: return buffer_len(&c->input);
1812: }
1813:
1814: static void
1815: channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1816: {
1817: u_int need;
1818: ssize_t len;
1819:
1.304 djm 1820: if (c->rfd != -1 && !c->mux_pause && FD_ISSET(c->rfd, readset) &&
1.302 djm 1821: (c->istate == CHAN_INPUT_OPEN ||
1822: c->istate == CHAN_INPUT_WAIT_DRAIN)) {
1823: /*
1824: * Don't not read past the precise end of packets to
1825: * avoid disrupting fd passing.
1826: */
1827: if (read_mux(c, 4) < 4) /* read header */
1828: return;
1829: need = get_u32(buffer_ptr(&c->input));
1830: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1831: if (need > CHANNEL_MUX_MAX_PACKET) {
1832: debug2("channel %d: packet too big %u > %u",
1833: c->self, CHANNEL_MUX_MAX_PACKET, need);
1834: chan_rcvd_oclose(c);
1835: return;
1836: }
1837: if (read_mux(c, need + 4) < need + 4) /* read body */
1838: return;
1839: if (c->mux_rcb(c) != 0) {
1840: debug("channel %d: mux_rcb failed", c->self);
1841: chan_mark_dead(c);
1842: return;
1843: }
1844: }
1845:
1846: if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) &&
1847: buffer_len(&c->output) > 0) {
1848: len = write(c->wfd, buffer_ptr(&c->output),
1849: buffer_len(&c->output));
1850: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1851: return;
1852: if (len <= 0) {
1853: chan_mark_dead(c);
1854: return;
1855: }
1856: buffer_consume(&c->output, len);
1857: }
1858: }
1859:
1860: static void
1861: channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset)
1862: {
1863: Channel *nc;
1864: struct sockaddr_storage addr;
1865: socklen_t addrlen;
1866: int newsock;
1867: uid_t euid;
1868: gid_t egid;
1869:
1870: if (!FD_ISSET(c->sock, readset))
1871: return;
1872:
1873: debug("multiplexing control connection");
1874:
1875: /*
1876: * Accept connection on control socket
1877: */
1878: memset(&addr, 0, sizeof(addr));
1879: addrlen = sizeof(addr);
1880: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
1881: &addrlen)) == -1) {
1882: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 1883: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1884: c->notbefore = monotime() + 1;
1.302 djm 1885: return;
1886: }
1887:
1888: if (getpeereid(newsock, &euid, &egid) < 0) {
1889: error("%s getpeereid failed: %s", __func__,
1890: strerror(errno));
1891: close(newsock);
1892: return;
1893: }
1894: if ((euid != 0) && (getuid() != euid)) {
1895: error("multiplex uid mismatch: peer euid %u != uid %u",
1896: (u_int)euid, (u_int)getuid());
1897: close(newsock);
1898: return;
1899: }
1900: nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT,
1901: newsock, newsock, -1, c->local_window_max,
1902: c->local_maxpacket, 0, "mux-control", 1);
1903: nc->mux_rcb = c->mux_rcb;
1904: debug3("%s: new mux channel %d fd %d", __func__,
1905: nc->self, nc->sock);
1906: /* establish state */
1907: nc->mux_rcb(nc);
1908: /* mux state transitions must not elicit protocol messages */
1909: nc->flags |= CHAN_LOCAL;
1910: }
1911:
1.127 itojun 1912: static void
1.358 djm 1913: channel_handler_init(void)
1.1 deraadt 1914: {
1.358 djm 1915: int i;
1.180 deraadt 1916:
1.358 djm 1917: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1918: channel_pre[i] = NULL;
1919: channel_post[i] = NULL;
1.41 markus 1920: }
1.157 markus 1921: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1922: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1923: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1924: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.336 millert 1925: channel_pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
1926: channel_pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
1.51 markus 1927: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1928: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1929: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1930: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.302 djm 1931: channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
1932: channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
1.44 markus 1933:
1.157 markus 1934: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 1935: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 1936: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.336 millert 1937: channel_post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
1938: channel_post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
1.51 markus 1939: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 1940: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 1941: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 1942: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.302 djm 1943: channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
1944: channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.44 markus 1945: }
1946:
1.140 markus 1947: /* gc dead channels */
1948: static void
1949: channel_garbage_collect(Channel *c)
1950: {
1951: if (c == NULL)
1952: return;
1953: if (c->detach_user != NULL) {
1.225 djm 1954: if (!chan_is_dead(c, c->detach_close))
1.140 markus 1955: return;
1.194 markus 1956: debug2("channel %d: gc: notify user", c->self);
1.140 markus 1957: c->detach_user(c->self, NULL);
1958: /* if we still have a callback */
1959: if (c->detach_user != NULL)
1960: return;
1.194 markus 1961: debug2("channel %d: gc: user detached", c->self);
1.140 markus 1962: }
1963: if (!chan_is_dead(c, 1))
1964: return;
1.194 markus 1965: debug2("channel %d: garbage collecting", c->self);
1.140 markus 1966: channel_free(c);
1967: }
1968:
1.127 itojun 1969: static void
1.317 djm 1970: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset,
1971: time_t *unpause_secs)
1.41 markus 1972: {
1973: static int did_init = 0;
1.299 markus 1974: u_int i, oalloc;
1.41 markus 1975: Channel *c;
1.317 djm 1976: time_t now;
1.25 markus 1977:
1.41 markus 1978: if (!did_init) {
1979: channel_handler_init();
1980: did_init = 1;
1981: }
1.322 dtucker 1982: now = monotime();
1.317 djm 1983: if (unpause_secs != NULL)
1984: *unpause_secs = 0;
1.299 markus 1985: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 1986: c = channels[i];
1987: if (c == NULL)
1.41 markus 1988: continue;
1.299 markus 1989: if (c->delayed) {
1990: if (ftab == channel_pre)
1991: c->delayed = 0;
1992: else
1993: continue;
1994: }
1.317 djm 1995: if (ftab[c->type] != NULL) {
1996: /*
1997: * Run handlers that are not paused.
1998: */
1999: if (c->notbefore <= now)
2000: (*ftab[c->type])(c, readset, writeset);
2001: else if (unpause_secs != NULL) {
2002: /*
2003: * Collect the time that the earliest
2004: * channel comes off pause.
2005: */
2006: debug3("%s: chan %d: skip for %d more seconds",
2007: __func__, c->self,
2008: (int)(c->notbefore - now));
2009: if (*unpause_secs == 0 ||
2010: (c->notbefore - now) < *unpause_secs)
2011: *unpause_secs = c->notbefore - now;
2012: }
2013: }
1.140 markus 2014: channel_garbage_collect(c);
1.1 deraadt 2015: }
1.317 djm 2016: if (unpause_secs != NULL && *unpause_secs != 0)
2017: debug3("%s: first channel unpauses in %d seconds",
2018: __func__, (int)*unpause_secs);
1.1 deraadt 2019: }
2020:
1.121 markus 2021: /*
2022: * Allocate/update select bitmasks and add any bits relevant to channels in
2023: * select bitmasks.
2024: */
1.49 markus 2025: void
1.100 markus 2026: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.318 djm 2027: u_int *nallocp, time_t *minwait_secs, int rekeying)
1.41 markus 2028: {
1.243 djm 2029: u_int n, sz, nfdset;
1.84 markus 2030:
1.352 deraadt 2031: n = MAXIMUM(*maxfdp, channel_max_fd);
1.84 markus 2032:
1.243 djm 2033: nfdset = howmany(n+1, NFDBITS);
2034: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2035: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2036: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2037: sz = nfdset * sizeof(fd_mask);
2038:
1.132 markus 2039: /* perhaps check sz < nalloc/2 and shrink? */
2040: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2041: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2042: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2043: *nallocp = sz;
1.84 markus 2044: }
1.132 markus 2045: *maxfdp = n;
1.84 markus 2046: memset(*readsetp, 0, sz);
2047: memset(*writesetp, 0, sz);
2048:
1.100 markus 2049: if (!rekeying)
1.317 djm 2050: channel_handler(channel_pre, *readsetp, *writesetp,
2051: minwait_secs);
1.41 markus 2052: }
2053:
1.121 markus 2054: /*
2055: * After select, perform any appropriate operations for channels which have
2056: * events pending.
2057: */
1.49 markus 2058: void
1.237 deraadt 2059: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 2060: {
1.317 djm 2061: channel_handler(channel_post, readset, writeset, NULL);
1.41 markus 2062: }
2063:
1.121 markus 2064:
1.84 markus 2065: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2066: void
1.142 itojun 2067: channel_output_poll(void)
1.1 deraadt 2068: {
1.41 markus 2069: Channel *c;
1.209 avsm 2070: u_int i, len;
1.1 deraadt 2071:
1.25 markus 2072: for (i = 0; i < channels_alloc; i++) {
1.113 markus 2073: c = channels[i];
2074: if (c == NULL)
2075: continue;
1.37 markus 2076:
1.121 markus 2077: /*
2078: * We are only interested in channels that can have buffered
2079: * incoming data.
2080: */
1.358 djm 2081: if (c->type != SSH_CHANNEL_OPEN)
2082: continue;
2083: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2084: /* XXX is this true? */
1.140 markus 2085: debug3("channel %d: will not send data after close", c->self);
1.44 markus 2086: continue;
2087: }
1.25 markus 2088:
2089: /* Get the amount of buffered data for this channel. */
1.93 markus 2090: if ((c->istate == CHAN_INPUT_OPEN ||
2091: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2092: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 2093: if (c->datagram) {
2094: if (len > 0) {
2095: u_char *data;
2096: u_int dlen;
2097:
2098: data = buffer_get_string(&c->input,
2099: &dlen);
1.309 djm 2100: if (dlen > c->remote_window ||
2101: dlen > c->remote_maxpacket) {
2102: debug("channel %d: datagram "
2103: "too big for channel",
2104: c->self);
1.321 djm 2105: free(data);
1.309 djm 2106: continue;
2107: }
1.228 reyk 2108: packet_start(SSH2_MSG_CHANNEL_DATA);
2109: packet_put_int(c->remote_id);
2110: packet_put_string(data, dlen);
2111: packet_send();
1.345 djm 2112: c->remote_window -= dlen;
1.321 djm 2113: free(data);
1.228 reyk 2114: }
2115: continue;
2116: }
1.121 markus 2117: /*
2118: * Send some data for the other side over the secure
2119: * connection.
2120: */
1.358 djm 2121: if (len > c->remote_window)
2122: len = c->remote_window;
2123: if (len > c->remote_maxpacket)
2124: len = c->remote_maxpacket;
1.41 markus 2125: if (len > 0) {
1.358 djm 2126: packet_start(SSH2_MSG_CHANNEL_DATA);
1.41 markus 2127: packet_put_int(c->remote_id);
2128: packet_put_string(buffer_ptr(&c->input), len);
2129: packet_send();
2130: buffer_consume(&c->input, len);
2131: c->remote_window -= len;
2132: }
2133: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.27 markus 2134: /*
2135: * input-buffer is empty and read-socket shutdown:
1.172 markus 2136: * tell peer, that we will not send more data: send IEOF.
2137: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2138: */
1.172 markus 2139: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2140: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2141: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2142: else
2143: chan_ibuf_empty(c);
1.25 markus 2144: }
1.44 markus 2145: /* Send extended data, i.e. stderr */
1.358 djm 2146: if (!(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2147: c->remote_window > 0 &&
2148: (len = buffer_len(&c->extended)) > 0 &&
2149: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2150: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2151: c->self, c->remote_window, buffer_len(&c->extended),
2152: c->extended_usage);
1.44 markus 2153: if (len > c->remote_window)
2154: len = c->remote_window;
2155: if (len > c->remote_maxpacket)
2156: len = c->remote_maxpacket;
2157: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2158: packet_put_int(c->remote_id);
2159: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2160: packet_put_string(buffer_ptr(&c->extended), len);
2161: packet_send();
2162: buffer_consume(&c->extended, len);
2163: c->remote_window -= len;
1.93 markus 2164: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2165: }
1.25 markus 2166: }
1.1 deraadt 2167: }
2168:
1.354 markus 2169: /* -- mux proxy support */
2170:
2171: /*
2172: * When multiplexing channel messages for mux clients we have to deal
2173: * with downstream messages from the mux client and upstream messages
2174: * from the ssh server:
2175: * 1) Handling downstream messages is straightforward and happens
2176: * in channel_proxy_downstream():
2177: * - We forward all messages (mostly) unmodified to the server.
2178: * - However, in order to route messages from upstream to the correct
2179: * downstream client, we have to replace the channel IDs used by the
2180: * mux clients with a unique channel ID because the mux clients might
2181: * use conflicting channel IDs.
2182: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2183: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2184: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2185: * with the newly allocated channel ID.
2186: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
2187: * channels and procesed by channel_proxy_upstream(). The local channel ID
2188: * is then translated back to the original mux client ID.
2189: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2190: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2191: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2192: * downstream mux client are removed.
2193: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2194: * requires more work, because they are not addressed to a specific
2195: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2196: * out whether the request is addressed to the local client or a
2197: * specific downstream client based on the listen-address/port.
2198: * 6) Agent and X11-Forwarding have a similar problem and are currenly
2199: * not supported as the matching session/channel cannot be identified
2200: * easily.
2201: */
2202:
2203: /*
2204: * receive packets from downstream mux clients:
2205: * channel callback fired on read from mux client, creates
2206: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2207: * on channel creation.
2208: */
2209: int
2210: channel_proxy_downstream(Channel *downstream)
2211: {
2212: Channel *c = NULL;
2213: struct ssh *ssh = active_state;
2214: struct sshbuf *original = NULL, *modified = NULL;
2215: const u_char *cp;
2216: char *ctype = NULL, *listen_host = NULL;
2217: u_char type;
2218: size_t have;
1.355 djm 2219: int ret = -1, r, idx;
2220: u_int id, remote_id, listen_port;
1.354 markus 2221:
2222: /* sshbuf_dump(&downstream->input, stderr); */
2223: if ((r = sshbuf_get_string_direct(&downstream->input, &cp, &have))
2224: != 0) {
2225: error("%s: malformed message: %s", __func__, ssh_err(r));
2226: return -1;
2227: }
2228: if (have < 2) {
2229: error("%s: short message", __func__);
2230: return -1;
2231: }
2232: type = cp[1];
2233: /* skip padlen + type */
2234: cp += 2;
2235: have -= 2;
2236: if (ssh_packet_log_type(type))
2237: debug3("%s: channel %u: down->up: type %u", __func__,
2238: downstream->self, type);
2239:
2240: switch (type) {
2241: case SSH2_MSG_CHANNEL_OPEN:
2242: if ((original = sshbuf_from(cp, have)) == NULL ||
2243: (modified = sshbuf_new()) == NULL) {
2244: error("%s: alloc", __func__);
2245: goto out;
2246: }
2247: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2248: (r = sshbuf_get_u32(original, &id)) != 0) {
2249: error("%s: parse error %s", __func__, ssh_err(r));
2250: goto out;
2251: }
2252: c = channel_new("mux proxy", SSH_CHANNEL_MUX_PROXY,
2253: -1, -1, -1, 0, 0, 0, ctype, 1);
2254: c->mux_ctx = downstream; /* point to mux client */
2255: c->mux_downstream_id = id; /* original downstream id */
2256: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2257: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2258: (r = sshbuf_putb(modified, original)) != 0) {
2259: error("%s: compose error %s", __func__, ssh_err(r));
2260: channel_free(c);
2261: goto out;
2262: }
2263: break;
2264: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2265: /*
2266: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2267: * need to parse 'remote_id' instead of 'ctype'.
2268: */
2269: if ((original = sshbuf_from(cp, have)) == NULL ||
2270: (modified = sshbuf_new()) == NULL) {
2271: error("%s: alloc", __func__);
2272: goto out;
2273: }
2274: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2275: (r = sshbuf_get_u32(original, &id)) != 0) {
2276: error("%s: parse error %s", __func__, ssh_err(r));
2277: goto out;
2278: }
2279: c = channel_new("mux proxy", SSH_CHANNEL_MUX_PROXY,
2280: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
2281: c->mux_ctx = downstream; /* point to mux client */
2282: c->mux_downstream_id = id;
2283: c->remote_id = remote_id;
2284: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2285: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2286: (r = sshbuf_putb(modified, original)) != 0) {
2287: error("%s: compose error %s", __func__, ssh_err(r));
2288: channel_free(c);
2289: goto out;
2290: }
2291: break;
2292: case SSH2_MSG_GLOBAL_REQUEST:
2293: if ((original = sshbuf_from(cp, have)) == NULL) {
2294: error("%s: alloc", __func__);
2295: goto out;
2296: }
2297: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
2298: error("%s: parse error %s", __func__, ssh_err(r));
2299: goto out;
2300: }
2301: if (strcmp(ctype, "tcpip-forward") != 0) {
2302: error("%s: unsupported request %s", __func__, ctype);
2303: goto out;
2304: }
2305: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2306: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2307: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
2308: error("%s: parse error %s", __func__, ssh_err(r));
2309: goto out;
2310: }
1.355 djm 2311: if (listen_port > 65535) {
2312: error("%s: tcpip-forward for %s: bad port %u",
2313: __func__, listen_host, listen_port);
2314: goto out;
2315: }
1.354 markus 2316: /* Record that connection to this host/port is permitted. */
2317: permitted_opens = xreallocarray(permitted_opens,
2318: num_permitted_opens + 1, sizeof(*permitted_opens));
2319: idx = num_permitted_opens++;
2320: permitted_opens[idx].host_to_connect = xstrdup("<mux>");
2321: permitted_opens[idx].port_to_connect = -1;
2322: permitted_opens[idx].listen_host = listen_host;
1.355 djm 2323: permitted_opens[idx].listen_port = (int)listen_port;
1.354 markus 2324: permitted_opens[idx].downstream = downstream;
2325: listen_host = NULL;
2326: break;
2327: case SSH2_MSG_CHANNEL_CLOSE:
2328: if (have < 4)
2329: break;
2330: remote_id = PEEK_U32(cp);
2331: if ((c = channel_by_remote_id(remote_id)) != NULL) {
2332: if (c->flags & CHAN_CLOSE_RCVD)
2333: channel_free(c);
2334: else
2335: c->flags |= CHAN_CLOSE_SENT;
2336: }
2337: break;
2338: }
2339: if (modified) {
2340: if ((r = sshpkt_start(ssh, type)) != 0 ||
2341: (r = sshpkt_putb(ssh, modified)) != 0 ||
2342: (r = sshpkt_send(ssh)) != 0) {
2343: error("%s: send %s", __func__, ssh_err(r));
2344: goto out;
2345: }
2346: } else {
2347: if ((r = sshpkt_start(ssh, type)) != 0 ||
2348: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2349: (r = sshpkt_send(ssh)) != 0) {
2350: error("%s: send %s", __func__, ssh_err(r));
2351: goto out;
2352: }
2353: }
2354: ret = 0;
2355: out:
2356: free(ctype);
2357: free(listen_host);
2358: sshbuf_free(original);
2359: sshbuf_free(modified);
2360: return ret;
2361: }
2362:
2363: /*
2364: * receive packets from upstream server and de-multiplex packets
2365: * to correct downstream:
2366: * implemented as a helper for channel input handlers,
2367: * replaces local (proxy) channel ID with downstream channel ID.
2368: */
2369: int
2370: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, void *ctxt)
2371: {
2372: struct ssh *ssh = active_state;
2373: struct sshbuf *b = NULL;
2374: Channel *downstream;
2375: const u_char *cp = NULL;
2376: size_t len;
2377: int r;
2378:
2379: /*
2380: * When receiving packets from the peer we need to check whether we
2381: * need to forward the packets to the mux client. In this case we
2382: * restore the orignal channel id and keep track of CLOSE messages,
2383: * so we can cleanup the channel.
2384: */
2385: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2386: return 0;
2387: if ((downstream = c->mux_ctx) == NULL)
2388: return 0;
2389: switch (type) {
2390: case SSH2_MSG_CHANNEL_CLOSE:
2391: case SSH2_MSG_CHANNEL_DATA:
2392: case SSH2_MSG_CHANNEL_EOF:
2393: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2394: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2395: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2396: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2397: case SSH2_MSG_CHANNEL_SUCCESS:
2398: case SSH2_MSG_CHANNEL_FAILURE:
2399: case SSH2_MSG_CHANNEL_REQUEST:
2400: break;
2401: default:
2402: debug2("%s: channel %u: unsupported type %u", __func__,
2403: c->self, type);
2404: return 0;
2405: }
2406: if ((b = sshbuf_new()) == NULL) {
2407: error("%s: alloc reply", __func__);
2408: goto out;
2409: }
2410: /* get remaining payload (after id) */
2411: cp = sshpkt_ptr(ssh, &len);
2412: if (cp == NULL) {
2413: error("%s: no packet", __func__);
2414: goto out;
2415: }
2416: /* translate id and send to muxclient */
2417: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2418: (r = sshbuf_put_u8(b, type)) != 0 ||
2419: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2420: (r = sshbuf_put(b, cp, len)) != 0 ||
2421: (r = sshbuf_put_stringb(&downstream->output, b)) != 0) {
2422: error("%s: compose for muxclient %s", __func__, ssh_err(r));
2423: goto out;
2424: }
2425: /* sshbuf_dump(b, stderr); */
2426: if (ssh_packet_log_type(type))
2427: debug3("%s: channel %u: up->down: type %u", __func__, c->self,
2428: type);
2429: out:
2430: /* update state */
2431: switch (type) {
2432: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2433: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
2434: if (cp && len > 4)
2435: c->remote_id = PEEK_U32(cp);
2436: break;
2437: case SSH2_MSG_CHANNEL_CLOSE:
2438: if (c->flags & CHAN_CLOSE_SENT)
2439: channel_free(c);
2440: else
2441: c->flags |= CHAN_CLOSE_RCVD;
2442: break;
2443: }
2444: sshbuf_free(b);
2445: return 1;
2446: }
1.121 markus 2447:
2448: /* -- protocol input */
1.249 djm 2449:
2450: /* ARGSUSED */
1.339 markus 2451: int
1.154 markus 2452: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2453: {
1.37 markus 2454: int id;
1.332 djm 2455: const u_char *data;
1.309 djm 2456: u_int data_len, win_len;
1.41 markus 2457: Channel *c;
1.25 markus 2458:
2459: /* Get the channel number and verify it. */
1.37 markus 2460: id = packet_get_int();
1.41 markus 2461: c = channel_lookup(id);
2462: if (c == NULL)
1.37 markus 2463: packet_disconnect("Received data for nonexistent channel %d.", id);
1.354 markus 2464: if (channel_proxy_upstream(c, type, seq, ctxt))
2465: return 0;
1.25 markus 2466:
2467: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2468: if (c->type != SSH_CHANNEL_OPEN &&
2469: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2470: return 0;
1.37 markus 2471:
1.25 markus 2472: /* Get the data. */
1.274 markus 2473: data = packet_get_string_ptr(&data_len);
1.309 djm 2474: win_len = data_len;
2475: if (c->datagram)
2476: win_len += 4; /* string length header */
1.200 markus 2477:
2478: /*
2479: * Ignore data for protocol > 1.3 if output end is no longer open.
2480: * For protocol 2 the sending side is reducing its window as it sends
2481: * data, so we must 'fake' consumption of the data in order to ensure
2482: * that window updates are sent back. Otherwise the connection might
2483: * deadlock.
2484: */
1.358 djm 2485: if (c->ostate != CHAN_OUTPUT_OPEN) {
2486: c->local_window -= win_len;
2487: c->local_consumed += win_len;
1.339 markus 2488: return 0;
1.200 markus 2489: }
1.41 markus 2490:
1.358 djm 2491: if (win_len > c->local_maxpacket) {
2492: logit("channel %d: rcvd big packet %d, maxpack %d",
2493: c->self, win_len, c->local_maxpacket);
2494: }
2495: if (win_len > c->local_window) {
2496: logit("channel %d: rcvd too much data %d, win %d",
2497: c->self, win_len, c->local_window);
2498: return 0;
1.44 markus 2499: }
1.358 djm 2500: c->local_window -= win_len;
2501:
1.228 reyk 2502: if (c->datagram)
2503: buffer_put_string(&c->output, data, data_len);
2504: else
2505: buffer_append(&c->output, data, data_len);
1.274 markus 2506: packet_check_eom();
1.339 markus 2507: return 0;
1.1 deraadt 2508: }
1.121 markus 2509:
1.249 djm 2510: /* ARGSUSED */
1.339 markus 2511: int
1.154 markus 2512: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2513: {
2514: int id;
2515: char *data;
1.177 markus 2516: u_int data_len, tcode;
1.44 markus 2517: Channel *c;
2518:
2519: /* Get the channel number and verify it. */
2520: id = packet_get_int();
2521: c = channel_lookup(id);
2522:
2523: if (c == NULL)
2524: packet_disconnect("Received extended_data for bad channel %d.", id);
1.354 markus 2525: if (channel_proxy_upstream(c, type, seq, ctxt))
2526: return 0;
1.44 markus 2527: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2528: logit("channel %d: ext data for non open", id);
1.339 markus 2529: return 0;
1.172 markus 2530: }
2531: if (c->flags & CHAN_EOF_RCVD) {
2532: if (datafellows & SSH_BUG_EXTEOF)
2533: debug("channel %d: accepting ext data after eof", id);
2534: else
2535: packet_disconnect("Received extended_data after EOF "
2536: "on channel %d.", id);
1.44 markus 2537: }
2538: tcode = packet_get_int();
2539: if (c->efd == -1 ||
2540: c->extended_usage != CHAN_EXTENDED_WRITE ||
2541: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2542: logit("channel %d: bad ext data", c->self);
1.339 markus 2543: return 0;
1.44 markus 2544: }
2545: data = packet_get_string(&data_len);
1.152 markus 2546: packet_check_eom();
1.44 markus 2547: if (data_len > c->local_window) {
1.188 itojun 2548: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2549: c->self, data_len, c->local_window);
1.321 djm 2550: free(data);
1.339 markus 2551: return 0;
1.44 markus 2552: }
1.70 markus 2553: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2554: c->local_window -= data_len;
2555: buffer_append(&c->extended, data, data_len);
1.321 djm 2556: free(data);
1.339 markus 2557: return 0;
1.44 markus 2558: }
2559:
1.249 djm 2560: /* ARGSUSED */
1.339 markus 2561: int
1.154 markus 2562: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2563: {
2564: int id;
2565: Channel *c;
2566:
2567: id = packet_get_int();
1.152 markus 2568: packet_check_eom();
1.41 markus 2569: c = channel_lookup(id);
2570: if (c == NULL)
2571: packet_disconnect("Received ieof for nonexistent channel %d.", id);
1.354 markus 2572: if (channel_proxy_upstream(c, type, seq, ctxt))
2573: return 0;
1.41 markus 2574: chan_rcvd_ieof(c);
1.133 markus 2575:
2576: /* XXX force input close */
1.156 markus 2577: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2578: debug("channel %d: FORCE input drain", c->self);
2579: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2580: if (buffer_len(&c->input) == 0)
2581: chan_ibuf_empty(c);
1.133 markus 2582: }
1.339 markus 2583: return 0;
1.41 markus 2584: }
1.1 deraadt 2585:
1.249 djm 2586: /* ARGSUSED */
1.339 markus 2587: int
1.154 markus 2588: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2589: {
2590: int id = packet_get_int();
2591: Channel *c = channel_lookup(id);
1.151 markus 2592:
1.41 markus 2593: if (c == NULL)
2594: packet_disconnect("Received oclose for nonexistent channel %d.", id);
1.354 markus 2595: if (channel_proxy_upstream(c, type, seq, ctxt))
2596: return 0;
2597: packet_check_eom();
1.41 markus 2598: chan_rcvd_oclose(c);
1.339 markus 2599: return 0;
1.1 deraadt 2600: }
2601:
1.249 djm 2602: /* ARGSUSED */
1.339 markus 2603: int
1.154 markus 2604: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2605: {
1.41 markus 2606: int id, remote_id;
2607: Channel *c;
1.1 deraadt 2608:
1.41 markus 2609: id = packet_get_int();
2610: c = channel_lookup(id);
1.25 markus 2611:
1.354 markus 2612: if (c==NULL)
2613: packet_disconnect("Received open confirmation for "
2614: "unknown channel %d.", id);
2615: if (channel_proxy_upstream(c, type, seq, ctxt))
2616: return 0;
2617: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 2618: packet_disconnect("Received open confirmation for "
2619: "non-opening channel %d.", id);
2620: remote_id = packet_get_int();
1.27 markus 2621: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2622: c->remote_id = remote_id;
2623: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2624:
1.358 djm 2625: c->remote_window = packet_get_int();
2626: c->remote_maxpacket = packet_get_int();
2627: if (c->open_confirm) {
2628: debug2("callback start");
2629: c->open_confirm(c->self, 1, c->open_confirm_ctx);
2630: debug2("callback done");
1.44 markus 2631: }
1.358 djm 2632: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
2633: c->remote_window, c->remote_maxpacket);
1.152 markus 2634: packet_check_eom();
1.339 markus 2635: return 0;
1.1 deraadt 2636: }
2637:
1.127 itojun 2638: static char *
1.114 markus 2639: reason2txt(int reason)
2640: {
1.143 deraadt 2641: switch (reason) {
1.114 markus 2642: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2643: return "administratively prohibited";
2644: case SSH2_OPEN_CONNECT_FAILED:
2645: return "connect failed";
2646: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2647: return "unknown channel type";
2648: case SSH2_OPEN_RESOURCE_SHORTAGE:
2649: return "resource shortage";
2650: }
1.117 stevesk 2651: return "unknown reason";
1.114 markus 2652: }
2653:
1.249 djm 2654: /* ARGSUSED */
1.339 markus 2655: int
1.154 markus 2656: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2657: {
1.86 markus 2658: int id, reason;
2659: char *msg = NULL, *lang = NULL;
1.41 markus 2660: Channel *c;
2661:
2662: id = packet_get_int();
2663: c = channel_lookup(id);
1.25 markus 2664:
1.354 markus 2665: if (c==NULL)
2666: packet_disconnect("Received open failure for "
2667: "unknown channel %d.", id);
2668: if (channel_proxy_upstream(c, type, seq, ctxt))
2669: return 0;
2670: if (c->type != SSH_CHANNEL_OPENING)
1.41 markus 2671: packet_disconnect("Received open failure for "
2672: "non-opening channel %d.", id);
1.358 djm 2673: reason = packet_get_int();
2674: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
2675: msg = packet_get_string(NULL);
2676: lang = packet_get_string(NULL);
2677: }
2678: logit("channel %d: open failed: %s%s%s", id,
2679: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
2680: free(msg);
2681: free(lang);
2682: if (c->open_confirm) {
2683: debug2("callback start");
2684: c->open_confirm(c->self, 0, c->open_confirm_ctx);
2685: debug2("callback done");
1.44 markus 2686: }
1.152 markus 2687: packet_check_eom();
1.291 djm 2688: /* Schedule the channel for cleanup/deletion. */
2689: chan_mark_dead(c);
1.339 markus 2690: return 0;
1.44 markus 2691: }
2692:
1.249 djm 2693: /* ARGSUSED */
1.339 markus 2694: int
1.154 markus 2695: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2696: {
2697: Channel *c;
1.178 markus 2698: int id;
1.346 djm 2699: u_int adjust, tmp;
1.121 markus 2700:
2701: /* Get the channel number and verify it. */
2702: id = packet_get_int();
2703: c = channel_lookup(id);
1.1 deraadt 2704:
1.229 markus 2705: if (c == NULL) {
2706: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 2707: return 0;
1.121 markus 2708: }
1.354 markus 2709: if (channel_proxy_upstream(c, type, seq, ctxt))
2710: return 0;
1.121 markus 2711: adjust = packet_get_int();
1.152 markus 2712: packet_check_eom();
1.178 markus 2713: debug2("channel %d: rcvd adjust %u", id, adjust);
1.346 djm 2714: if ((tmp = c->remote_window + adjust) < c->remote_window)
2715: fatal("channel %d: adjust %u overflows remote window %u",
2716: id, adjust, c->remote_window);
2717: c->remote_window = tmp;
1.339 markus 2718: return 0;
1.121 markus 2719: }
1.1 deraadt 2720:
1.249 djm 2721: /* ARGSUSED */
1.339 markus 2722: int
1.275 djm 2723: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2724: {
2725: Channel *c;
2726: struct channel_confirm *cc;
1.289 markus 2727: int id;
1.275 djm 2728:
2729: /* Reset keepalive timeout */
1.296 andreas 2730: packet_set_alive_timeouts(0);
1.275 djm 2731:
1.289 markus 2732: id = packet_get_int();
2733: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2734:
1.289 markus 2735: if ((c = channel_lookup(id)) == NULL) {
2736: logit("channel_input_status_confirm: %d: unknown", id);
1.339 markus 2737: return 0;
1.275 djm 2738: }
1.354 markus 2739: if (channel_proxy_upstream(c, type, seq, ctxt))
2740: return 0;
2741: packet_check_eom();
1.275 djm 2742: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 2743: return 0;
1.275 djm 2744: cc->cb(type, c, cc->ctx);
2745: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 2746: explicit_bzero(cc, sizeof(*cc));
1.321 djm 2747: free(cc);
1.339 markus 2748: return 0;
1.275 djm 2749: }
1.121 markus 2750:
2751: /* -- tcp forwarding */
1.135 markus 2752:
2753: void
2754: channel_set_af(int af)
2755: {
2756: IPv4or6 = af;
2757: }
1.121 markus 2758:
1.312 djm 2759:
2760: /*
2761: * Determine whether or not a port forward listens to loopback, the
2762: * specified address or wildcard. On the client, a specified bind
2763: * address will always override gateway_ports. On the server, a
2764: * gateway_ports of 1 (``yes'') will override the client's specification
2765: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
2766: * will bind to whatever address the client asked for.
2767: *
2768: * Special-case listen_addrs are:
2769: *
2770: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2771: * "" (empty string), "*" -> wildcard v4/v6
2772: * "localhost" -> loopback v4/v6
1.334 djm 2773: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 2774: */
2775: static const char *
2776: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 2777: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 2778: {
2779: const char *addr = NULL;
2780: int wildcard = 0;
2781:
2782: if (listen_addr == NULL) {
2783: /* No address specified: default to gateway_ports setting */
1.336 millert 2784: if (fwd_opts->gateway_ports)
1.312 djm 2785: wildcard = 1;
1.336 millert 2786: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 2787: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2788: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
2789: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 2790: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 2791: wildcard = 1;
1.326 djm 2792: /*
2793: * Notify client if they requested a specific listen
2794: * address and it was overridden.
2795: */
2796: if (*listen_addr != '\0' &&
2797: strcmp(listen_addr, "0.0.0.0") != 0 &&
2798: strcmp(listen_addr, "*") != 0) {
2799: packet_send_debug("Forwarding listen address "
2800: "\"%s\" overridden by server "
2801: "GatewayPorts", listen_addr);
2802: }
1.334 djm 2803: } else if (strcmp(listen_addr, "localhost") != 0 ||
2804: strcmp(listen_addr, "127.0.0.1") == 0 ||
2805: strcmp(listen_addr, "::1") == 0) {
2806: /* Accept localhost address when GatewayPorts=yes */
2807: addr = listen_addr;
1.326 djm 2808: }
1.334 djm 2809: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
2810: strcmp(listen_addr, "::1") == 0) {
2811: /*
2812: * If a specific IPv4/IPv6 localhost address has been
2813: * requested then accept it even if gateway_ports is in
2814: * effect. This allows the client to prefer IPv4 or IPv6.
2815: */
2816: addr = listen_addr;
1.312 djm 2817: }
2818: if (wildcardp != NULL)
2819: *wildcardp = wildcard;
2820: return addr;
2821: }
2822:
1.160 markus 2823: static int
1.336 millert 2824: channel_setup_fwd_listener_tcpip(int type, struct Forward *fwd,
2825: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.25 markus 2826: {
1.113 markus 2827: Channel *c;
1.226 djm 2828: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2829: struct addrinfo hints, *ai, *aitop;
1.212 djm 2830: const char *host, *addr;
1.35 markus 2831: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2832: in_port_t *lport_p;
1.25 markus 2833:
1.212 djm 2834: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2835:
1.344 millert 2836: if (is_client && fwd->connect_path != NULL) {
2837: host = fwd->connect_path;
2838: } else {
2839: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2840: fwd->listen_host : fwd->connect_host;
2841: if (host == NULL) {
2842: error("No forward host name.");
2843: return 0;
2844: }
2845: if (strlen(host) >= NI_MAXHOST) {
2846: error("Forward host name too long.");
2847: return 0;
2848: }
1.87 markus 2849: }
1.25 markus 2850:
1.312 djm 2851: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 2852: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
2853: is_client, fwd_opts);
2854: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 2855: type, wildcard, (addr == NULL) ? "NULL" : addr);
2856:
2857: /*
1.35 markus 2858: * getaddrinfo returns a loopback address if the hostname is
2859: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2860: */
1.35 markus 2861: memset(&hints, 0, sizeof(hints));
2862: hints.ai_family = IPv4or6;
1.212 djm 2863: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2864: hints.ai_socktype = SOCK_STREAM;
1.336 millert 2865: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 2866: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2867: if (addr == NULL) {
2868: /* This really shouldn't happen */
2869: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2870: ssh_gai_strerror(r));
1.212 djm 2871: } else {
1.336 millert 2872: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 2873: ssh_gai_strerror(r));
1.212 djm 2874: }
1.218 markus 2875: return 0;
1.212 djm 2876: }
1.295 djm 2877: if (allocated_listen_port != NULL)
2878: *allocated_listen_port = 0;
1.35 markus 2879: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2880: switch (ai->ai_family) {
2881: case AF_INET:
2882: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2883: sin_port;
2884: break;
2885: case AF_INET6:
2886: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2887: sin6_port;
2888: break;
2889: default:
1.35 markus 2890: continue;
1.295 djm 2891: }
2892: /*
2893: * If allocating a port for -R forwards, then use the
2894: * same port for all address families.
2895: */
1.336 millert 2896: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2897: allocated_listen_port != NULL && *allocated_listen_port > 0)
2898: *lport_p = htons(*allocated_listen_port);
2899:
1.35 markus 2900: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2901: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 2902: error("%s: getnameinfo failed", __func__);
1.35 markus 2903: continue;
2904: }
2905: /* Create a port to listen for the host. */
1.300 dtucker 2906: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2907: if (sock < 0) {
2908: /* this is no error since kernel may not support ipv6 */
2909: verbose("socket: %.100s", strerror(errno));
2910: continue;
2911: }
1.226 djm 2912:
2913: channel_set_reuseaddr(sock);
1.182 stevesk 2914:
1.295 djm 2915: debug("Local forwarding listening on %s port %s.",
2916: ntop, strport);
1.35 markus 2917:
2918: /* Bind the socket to the address. */
2919: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2920: /* address can be in use ipv6 address is already bound */
2921: verbose("bind: %.100s", strerror(errno));
2922: close(sock);
2923: continue;
2924: }
2925: /* Start listening for connections on the socket. */
1.199 markus 2926: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2927: error("listen: %.100s", strerror(errno));
2928: close(sock);
2929: continue;
2930: }
1.295 djm 2931:
2932: /*
1.336 millert 2933: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 2934: * record what we got.
2935: */
1.336 millert 2936: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2937: allocated_listen_port != NULL &&
2938: *allocated_listen_port == 0) {
1.350 djm 2939: *allocated_listen_port = get_local_port(sock);
1.295 djm 2940: debug("Allocated listen port %d",
2941: *allocated_listen_port);
2942: }
2943:
1.35 markus 2944: /* Allocate a channel number for the socket. */
1.121 markus 2945: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2946: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2947: 0, "port listener", 1);
1.293 djm 2948: c->path = xstrdup(host);
1.336 millert 2949: c->host_port = fwd->connect_port;
1.312 djm 2950: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 2951: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 2952: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
2953: c->listening_port = *allocated_listen_port;
2954: else
1.336 millert 2955: c->listening_port = fwd->listen_port;
1.35 markus 2956: success = 1;
2957: }
2958: if (success == 0)
1.336 millert 2959: error("%s: cannot listen to port: %d", __func__,
2960: fwd->listen_port);
1.35 markus 2961: freeaddrinfo(aitop);
1.87 markus 2962: return success;
1.25 markus 2963: }
1.1 deraadt 2964:
1.336 millert 2965: static int
2966: channel_setup_fwd_listener_streamlocal(int type, struct Forward *fwd,
2967: struct ForwardOptions *fwd_opts)
2968: {
2969: struct sockaddr_un sunaddr;
2970: const char *path;
2971: Channel *c;
2972: int port, sock;
2973: mode_t omask;
2974:
2975: switch (type) {
2976: case SSH_CHANNEL_UNIX_LISTENER:
2977: if (fwd->connect_path != NULL) {
2978: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
2979: error("Local connecting path too long: %s",
2980: fwd->connect_path);
2981: return 0;
2982: }
2983: path = fwd->connect_path;
2984: port = PORT_STREAMLOCAL;
2985: } else {
2986: if (fwd->connect_host == NULL) {
2987: error("No forward host name.");
2988: return 0;
2989: }
2990: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
2991: error("Forward host name too long.");
2992: return 0;
2993: }
2994: path = fwd->connect_host;
2995: port = fwd->connect_port;
2996: }
2997: break;
2998: case SSH_CHANNEL_RUNIX_LISTENER:
2999: path = fwd->listen_path;
3000: port = PORT_STREAMLOCAL;
3001: break;
3002: default:
3003: error("%s: unexpected channel type %d", __func__, type);
3004: return 0;
3005: }
3006:
3007: if (fwd->listen_path == NULL) {
3008: error("No forward path name.");
3009: return 0;
3010: }
3011: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3012: error("Local listening path too long: %s", fwd->listen_path);
3013: return 0;
3014: }
3015:
3016: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
3017:
3018: /* Start a Unix domain listener. */
3019: omask = umask(fwd_opts->streamlocal_bind_mask);
3020: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3021: fwd_opts->streamlocal_bind_unlink);
3022: umask(omask);
3023: if (sock < 0)
3024: return 0;
3025:
3026: debug("Local forwarding listening on path %s.", fwd->listen_path);
3027:
3028: /* Allocate a channel number for the socket. */
3029: c = channel_new("unix listener", type, sock, sock, -1,
3030: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3031: 0, "unix listener", 1);
3032: c->path = xstrdup(path);
3033: c->host_port = port;
3034: c->listening_port = PORT_STREAMLOCAL;
3035: c->listening_addr = xstrdup(fwd->listen_path);
3036: return 1;
3037: }
3038:
3039: static int
3040: channel_cancel_rport_listener_tcpip(const char *host, u_short port)
1.202 djm 3041: {
1.209 avsm 3042: u_int i;
3043: int found = 0;
1.202 djm 3044:
1.213 deraadt 3045: for (i = 0; i < channels_alloc; i++) {
1.202 djm 3046: Channel *c = channels[i];
1.312 djm 3047: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3048: continue;
3049: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3050: debug2("%s: close channel %d", __func__, i);
3051: channel_free(c);
3052: found = 1;
3053: }
3054: }
3055:
3056: return (found);
3057: }
3058:
1.336 millert 3059: static int
3060: channel_cancel_rport_listener_streamlocal(const char *path)
3061: {
3062: u_int i;
3063: int found = 0;
3064:
3065: for (i = 0; i < channels_alloc; i++) {
3066: Channel *c = channels[i];
3067: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3068: continue;
3069: if (c->path == NULL)
3070: continue;
3071: if (strcmp(c->path, path) == 0) {
3072: debug2("%s: close channel %d", __func__, i);
3073: channel_free(c);
3074: found = 1;
3075: }
3076: }
3077:
3078: return (found);
3079: }
3080:
1.312 djm 3081: int
1.336 millert 3082: channel_cancel_rport_listener(struct Forward *fwd)
3083: {
3084: if (fwd->listen_path != NULL)
3085: return channel_cancel_rport_listener_streamlocal(fwd->listen_path);
3086: else
3087: return channel_cancel_rport_listener_tcpip(fwd->listen_host, fwd->listen_port);
3088: }
3089:
3090: static int
3091: channel_cancel_lport_listener_tcpip(const char *lhost, u_short lport,
3092: int cport, struct ForwardOptions *fwd_opts)
1.312 djm 3093: {
3094: u_int i;
3095: int found = 0;
1.336 millert 3096: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3097:
1.312 djm 3098: for (i = 0; i < channels_alloc; i++) {
3099: Channel *c = channels[i];
3100: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3101: continue;
1.313 markus 3102: if (c->listening_port != lport)
1.312 djm 3103: continue;
1.313 markus 3104: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3105: /* skip dynamic forwardings */
3106: if (c->host_port == 0)
3107: continue;
3108: } else {
3109: if (c->host_port != cport)
3110: continue;
3111: }
1.312 djm 3112: if ((c->listening_addr == NULL && addr != NULL) ||
3113: (c->listening_addr != NULL && addr == NULL))
3114: continue;
3115: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3116: debug2("%s: close channel %d", __func__, i);
1.202 djm 3117: channel_free(c);
3118: found = 1;
3119: }
3120: }
3121:
3122: return (found);
3123: }
3124:
1.336 millert 3125: static int
3126: channel_cancel_lport_listener_streamlocal(const char *path)
3127: {
3128: u_int i;
3129: int found = 0;
3130:
3131: if (path == NULL) {
3132: error("%s: no path specified.", __func__);
3133: return 0;
3134: }
3135:
3136: for (i = 0; i < channels_alloc; i++) {
3137: Channel *c = channels[i];
3138: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3139: continue;
3140: if (c->listening_addr == NULL)
3141: continue;
3142: if (strcmp(c->listening_addr, path) == 0) {
3143: debug2("%s: close channel %d", __func__, i);
3144: channel_free(c);
3145: found = 1;
3146: }
3147: }
3148:
3149: return (found);
3150: }
3151:
3152: int
3153: channel_cancel_lport_listener(struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
3154: {
3155: if (fwd->listen_path != NULL)
3156: return channel_cancel_lport_listener_streamlocal(fwd->listen_path);
3157: else
3158: return channel_cancel_lport_listener_tcpip(fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3159: }
3160:
1.160 markus 3161: /* protocol local port fwd, used by ssh (and sshd in v1) */
3162: int
1.336 millert 3163: channel_setup_local_fwd_listener(struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3164: {
1.336 millert 3165: if (fwd->listen_path != NULL) {
3166: return channel_setup_fwd_listener_streamlocal(
3167: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3168: } else {
3169: return channel_setup_fwd_listener_tcpip(SSH_CHANNEL_PORT_LISTENER,
3170: fwd, NULL, fwd_opts);
3171: }
1.160 markus 3172: }
3173:
3174: /* protocol v2 remote port fwd, used by sshd */
3175: int
1.336 millert 3176: channel_setup_remote_fwd_listener(struct Forward *fwd,
3177: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3178: {
1.336 millert 3179: if (fwd->listen_path != NULL) {
3180: return channel_setup_fwd_listener_streamlocal(
3181: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3182: } else {
3183: return channel_setup_fwd_listener_tcpip(
3184: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3185: fwd_opts);
3186: }
1.160 markus 3187: }
3188:
1.27 markus 3189: /*
1.312 djm 3190: * Translate the requested rfwd listen host to something usable for
3191: * this server.
3192: */
3193: static const char *
3194: channel_rfwd_bind_host(const char *listen_host)
3195: {
3196: if (listen_host == NULL) {
3197: if (datafellows & SSH_BUG_RFWD_ADDR)
3198: return "127.0.0.1";
3199: else
3200: return "localhost";
3201: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3202: if (datafellows & SSH_BUG_RFWD_ADDR)
3203: return "0.0.0.0";
3204: else
3205: return "";
3206: } else
3207: return listen_host;
3208: }
3209:
3210: /*
1.27 markus 3211: * Initiate forwarding of connections to port "port" on remote host through
3212: * the secure channel to host:port from local side.
1.315 markus 3213: * Returns handle (index) for updating the dynamic listen port with
3214: * channel_update_permitted_opens().
1.27 markus 3215: */
1.253 markus 3216: int
1.336 millert 3217: channel_request_remote_forwarding(struct Forward *fwd)
1.25 markus 3218: {
1.358 djm 3219: int success = 0, idx = -1;
1.73 markus 3220:
1.25 markus 3221: /* Send the forward request to the remote side. */
1.358 djm 3222: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3223: if (fwd->listen_path != NULL) {
3224: packet_put_cstring("streamlocal-forward@openssh.com");
3225: packet_put_char(1); /* boolean: want reply */
3226: packet_put_cstring(fwd->listen_path);
1.336 millert 3227: } else {
1.358 djm 3228: packet_put_cstring("tcpip-forward");
3229: packet_put_char(1); /* boolean: want reply */
3230: packet_put_cstring(channel_rfwd_bind_host(fwd->listen_host));
3231: packet_put_int(fwd->listen_port);
1.73 markus 3232: }
1.358 djm 3233: packet_send();
3234: packet_write_wait();
3235: /* Assume that server accepts the request */
3236: success = 1;
1.73 markus 3237: if (success) {
1.305 djm 3238: /* Record that connection to this host/port is permitted. */
1.342 deraadt 3239: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3240: num_permitted_opens + 1, sizeof(*permitted_opens));
1.315 markus 3241: idx = num_permitted_opens++;
1.336 millert 3242: if (fwd->connect_path != NULL) {
3243: permitted_opens[idx].host_to_connect =
3244: xstrdup(fwd->connect_path);
3245: permitted_opens[idx].port_to_connect =
3246: PORT_STREAMLOCAL;
3247: } else {
3248: permitted_opens[idx].host_to_connect =
3249: xstrdup(fwd->connect_host);
3250: permitted_opens[idx].port_to_connect =
3251: fwd->connect_port;
3252: }
3253: if (fwd->listen_path != NULL) {
3254: permitted_opens[idx].listen_host = NULL;
3255: permitted_opens[idx].listen_path =
3256: xstrdup(fwd->listen_path);
3257: permitted_opens[idx].listen_port = PORT_STREAMLOCAL;
3258: } else {
3259: permitted_opens[idx].listen_host =
3260: fwd->listen_host ? xstrdup(fwd->listen_host) : NULL;
3261: permitted_opens[idx].listen_path = NULL;
3262: permitted_opens[idx].listen_port = fwd->listen_port;
3263: }
1.354 markus 3264: permitted_opens[idx].downstream = NULL;
1.44 markus 3265: }
1.315 markus 3266: return (idx);
1.1 deraadt 3267: }
3268:
1.333 markus 3269: static int
3270: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3271: int requestedport)
1.333 markus 3272: {
3273: if (allowed_open->host_to_connect == NULL)
3274: return 0;
3275: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3276: allowed_open->port_to_connect != requestedport)
3277: return 0;
1.351 dtucker 3278: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3279: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3280: return 0;
3281: return 1;
3282: }
3283:
3284: /*
1.336 millert 3285: * Note that in the listen host/port case
1.333 markus 3286: * we don't support FWD_PERMIT_ANY_PORT and
3287: * need to translate between the configured-host (listen_host)
3288: * and what we've sent to the remote server (channel_rfwd_bind_host)
3289: */
3290: static int
1.336 millert 3291: open_listen_match_tcpip(ForwardPermission *allowed_open,
3292: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3293: {
3294: const char *allowed_host;
3295:
3296: if (allowed_open->host_to_connect == NULL)
3297: return 0;
3298: if (allowed_open->listen_port != requestedport)
3299: return 0;
1.335 djm 3300: if (!translate && allowed_open->listen_host == NULL &&
3301: requestedhost == NULL)
3302: return 1;
1.333 markus 3303: allowed_host = translate ?
3304: channel_rfwd_bind_host(allowed_open->listen_host) :
3305: allowed_open->listen_host;
3306: if (allowed_host == NULL ||
3307: strcmp(allowed_host, requestedhost) != 0)
3308: return 0;
3309: return 1;
3310: }
3311:
1.336 millert 3312: static int
3313: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3314: const char *requestedpath)
3315: {
3316: if (allowed_open->host_to_connect == NULL)
3317: return 0;
3318: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3319: return 0;
3320: if (allowed_open->listen_path == NULL ||
3321: strcmp(allowed_open->listen_path, requestedpath) != 0)
3322: return 0;
3323: return 1;
3324: }
3325:
1.27 markus 3326: /*
1.208 deraadt 3327: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3328: * local side.
3329: */
1.336 millert 3330: static int
3331: channel_request_rforward_cancel_tcpip(const char *host, u_short port)
1.202 djm 3332: {
3333: int i;
3334:
3335: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3336: if (open_listen_match_tcpip(&permitted_opens[i], host, port, 0))
1.202 djm 3337: break;
3338: }
3339: if (i >= num_permitted_opens) {
3340: debug("%s: requested forward not found", __func__);
1.312 djm 3341: return -1;
1.202 djm 3342: }
3343: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3344: packet_put_cstring("cancel-tcpip-forward");
3345: packet_put_char(0);
1.312 djm 3346: packet_put_cstring(channel_rfwd_bind_host(host));
1.202 djm 3347: packet_put_int(port);
3348: packet_send();
3349:
1.336 millert 3350: permitted_opens[i].listen_port = 0;
1.333 markus 3351: permitted_opens[i].port_to_connect = 0;
1.336 millert 3352: free(permitted_opens[i].host_to_connect);
3353: permitted_opens[i].host_to_connect = NULL;
3354: free(permitted_opens[i].listen_host);
3355: permitted_opens[i].listen_host = NULL;
3356: permitted_opens[i].listen_path = NULL;
1.354 markus 3357: permitted_opens[i].downstream = NULL;
1.336 millert 3358:
3359: return 0;
3360: }
3361:
3362: /*
3363: * Request cancellation of remote forwarding of Unix domain socket
3364: * path from local side.
3365: */
3366: static int
3367: channel_request_rforward_cancel_streamlocal(const char *path)
3368: {
3369: int i;
3370:
3371: for (i = 0; i < num_permitted_opens; i++) {
3372: if (open_listen_match_streamlocal(&permitted_opens[i], path))
3373: break;
3374: }
3375: if (i >= num_permitted_opens) {
3376: debug("%s: requested forward not found", __func__);
3377: return -1;
3378: }
3379: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3380: packet_put_cstring("cancel-streamlocal-forward@openssh.com");
3381: packet_put_char(0);
3382: packet_put_cstring(path);
3383: packet_send();
3384:
1.202 djm 3385: permitted_opens[i].listen_port = 0;
1.336 millert 3386: permitted_opens[i].port_to_connect = 0;
1.321 djm 3387: free(permitted_opens[i].host_to_connect);
1.202 djm 3388: permitted_opens[i].host_to_connect = NULL;
1.333 markus 3389: permitted_opens[i].listen_host = NULL;
1.336 millert 3390: free(permitted_opens[i].listen_path);
3391: permitted_opens[i].listen_path = NULL;
1.354 markus 3392: permitted_opens[i].downstream = NULL;
1.312 djm 3393:
3394: return 0;
1.202 djm 3395: }
3396:
3397: /*
1.336 millert 3398: * Request cancellation of remote forwarding of a connection from local side.
3399: */
3400: int
3401: channel_request_rforward_cancel(struct Forward *fwd)
3402: {
3403: if (fwd->listen_path != NULL) {
3404: return (channel_request_rforward_cancel_streamlocal(
3405: fwd->listen_path));
3406: } else {
3407: return (channel_request_rforward_cancel_tcpip(fwd->listen_host,
3408: fwd->listen_port ? fwd->listen_port : fwd->allocated_port));
3409: }
1.1 deraadt 3410: }
3411:
1.99 markus 3412: /*
3413: * Permits opening to any host/port if permitted_opens[] is empty. This is
3414: * usually called by the server, because the user could connect to any port
3415: * anyway, and the server has no way to know but to trust the client anyway.
3416: */
3417: void
1.142 itojun 3418: channel_permit_all_opens(void)
1.99 markus 3419: {
3420: if (num_permitted_opens == 0)
3421: all_opens_permitted = 1;
3422: }
3423:
1.101 markus 3424: void
1.99 markus 3425: channel_add_permitted_opens(char *host, int port)
3426: {
3427: debug("allow port forwarding to host %s port %d", host, port);
3428:
1.342 deraadt 3429: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3430: num_permitted_opens + 1, sizeof(*permitted_opens));
1.99 markus 3431: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
3432: permitted_opens[num_permitted_opens].port_to_connect = port;
1.333 markus 3433: permitted_opens[num_permitted_opens].listen_host = NULL;
1.336 millert 3434: permitted_opens[num_permitted_opens].listen_path = NULL;
1.333 markus 3435: permitted_opens[num_permitted_opens].listen_port = 0;
1.354 markus 3436: permitted_opens[num_permitted_opens].downstream = NULL;
1.99 markus 3437: num_permitted_opens++;
3438:
3439: all_opens_permitted = 0;
1.315 markus 3440: }
3441:
3442: /*
3443: * Update the listen port for a dynamic remote forward, after
3444: * the actual 'newport' has been allocated. If 'newport' < 0 is
3445: * passed then they entry will be invalidated.
3446: */
3447: void
3448: channel_update_permitted_opens(int idx, int newport)
3449: {
3450: if (idx < 0 || idx >= num_permitted_opens) {
3451: debug("channel_update_permitted_opens: index out of range:"
3452: " %d num_permitted_opens %d", idx, num_permitted_opens);
3453: return;
3454: }
3455: debug("%s allowed port %d for forwarding to host %s port %d",
3456: newport > 0 ? "Updating" : "Removing",
3457: newport,
3458: permitted_opens[idx].host_to_connect,
3459: permitted_opens[idx].port_to_connect);
3460: if (newport >= 0) {
3461: permitted_opens[idx].listen_port =
3462: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3463: } else {
3464: permitted_opens[idx].listen_port = 0;
3465: permitted_opens[idx].port_to_connect = 0;
1.321 djm 3466: free(permitted_opens[idx].host_to_connect);
1.315 markus 3467: permitted_opens[idx].host_to_connect = NULL;
1.333 markus 3468: free(permitted_opens[idx].listen_host);
3469: permitted_opens[idx].listen_host = NULL;
1.336 millert 3470: free(permitted_opens[idx].listen_path);
3471: permitted_opens[idx].listen_path = NULL;
1.315 markus 3472: }
1.99 markus 3473: }
3474:
1.258 dtucker 3475: int
1.257 dtucker 3476: channel_add_adm_permitted_opens(char *host, int port)
3477: {
1.258 dtucker 3478: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 3479:
1.342 deraadt 3480: permitted_adm_opens = xreallocarray(permitted_adm_opens,
1.305 djm 3481: num_adm_permitted_opens + 1, sizeof(*permitted_adm_opens));
1.257 dtucker 3482: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
3483: = xstrdup(host);
3484: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.333 markus 3485: permitted_adm_opens[num_adm_permitted_opens].listen_host = NULL;
1.336 millert 3486: permitted_adm_opens[num_adm_permitted_opens].listen_path = NULL;
1.333 markus 3487: permitted_adm_opens[num_adm_permitted_opens].listen_port = 0;
1.258 dtucker 3488: return ++num_adm_permitted_opens;
1.257 dtucker 3489: }
3490:
3491: void
1.316 dtucker 3492: channel_disable_adm_local_opens(void)
3493: {
1.319 djm 3494: channel_clear_adm_permitted_opens();
1.343 dtucker 3495: permitted_adm_opens = xcalloc(sizeof(*permitted_adm_opens), 1);
1.319 djm 3496: permitted_adm_opens[num_adm_permitted_opens].host_to_connect = NULL;
3497: num_adm_permitted_opens = 1;
1.316 dtucker 3498: }
3499:
3500: void
1.99 markus 3501: channel_clear_permitted_opens(void)
3502: {
3503: int i;
3504:
1.333 markus 3505: for (i = 0; i < num_permitted_opens; i++) {
1.321 djm 3506: free(permitted_opens[i].host_to_connect);
1.333 markus 3507: free(permitted_opens[i].listen_host);
1.336 millert 3508: free(permitted_opens[i].listen_path);
1.333 markus 3509: }
1.321 djm 3510: free(permitted_opens);
3511: permitted_opens = NULL;
1.99 markus 3512: num_permitted_opens = 0;
1.257 dtucker 3513: }
3514:
3515: void
3516: channel_clear_adm_permitted_opens(void)
3517: {
3518: int i;
1.99 markus 3519:
1.333 markus 3520: for (i = 0; i < num_adm_permitted_opens; i++) {
1.321 djm 3521: free(permitted_adm_opens[i].host_to_connect);
1.333 markus 3522: free(permitted_adm_opens[i].listen_host);
1.336 millert 3523: free(permitted_adm_opens[i].listen_path);
1.333 markus 3524: }
1.321 djm 3525: free(permitted_adm_opens);
3526: permitted_adm_opens = NULL;
1.257 dtucker 3527: num_adm_permitted_opens = 0;
1.278 dtucker 3528: }
3529:
3530: void
3531: channel_print_adm_permitted_opens(void)
3532: {
1.286 djm 3533: int i;
1.278 dtucker 3534:
1.290 stevesk 3535: printf("permitopen");
1.288 stevesk 3536: if (num_adm_permitted_opens == 0) {
1.290 stevesk 3537: printf(" any\n");
1.288 stevesk 3538: return;
3539: }
1.278 dtucker 3540: for (i = 0; i < num_adm_permitted_opens; i++)
1.316 dtucker 3541: if (permitted_adm_opens[i].host_to_connect == NULL)
3542: printf(" none");
3543: else
1.278 dtucker 3544: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
3545: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 3546: printf("\n");
1.99 markus 3547: }
3548:
1.314 dtucker 3549: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3550: int
3551: permitopen_port(const char *p)
3552: {
3553: int port;
3554:
3555: if (strcmp(p, "*") == 0)
3556: return FWD_PERMIT_ANY_PORT;
3557: if ((port = a2port(p)) > 0)
3558: return port;
3559: return -1;
3560: }
3561:
1.276 djm 3562: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3563: static int
1.276 djm 3564: connect_next(struct channel_connect *cctx)
1.41 markus 3565: {
1.276 djm 3566: int sock, saved_errno;
1.336 millert 3567: struct sockaddr_un *sunaddr;
1.352 deraadt 3568: char ntop[NI_MAXHOST], strport[MAXIMUM(NI_MAXSERV,sizeof(sunaddr->sun_path))];
1.41 markus 3569:
1.276 djm 3570: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3571: switch (cctx->ai->ai_family) {
3572: case AF_UNIX:
3573: /* unix:pathname instead of host:port */
3574: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3575: strlcpy(ntop, "unix", sizeof(ntop));
3576: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3577: break;
3578: case AF_INET:
3579: case AF_INET6:
3580: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3581: ntop, sizeof(ntop), strport, sizeof(strport),
3582: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3583: error("connect_next: getnameinfo failed");
3584: continue;
3585: }
3586: break;
3587: default:
1.41 markus 3588: continue;
3589: }
1.300 dtucker 3590: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3591: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3592: if (cctx->ai->ai_next == NULL)
1.186 djm 3593: error("socket: %.100s", strerror(errno));
3594: else
3595: verbose("socket: %.100s", strerror(errno));
1.41 markus 3596: continue;
3597: }
1.205 djm 3598: if (set_nonblock(sock) == -1)
3599: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3600: if (connect(sock, cctx->ai->ai_addr,
3601: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3602: debug("connect_next: host %.100s ([%.100s]:%s): "
3603: "%.100s", cctx->host, ntop, strport,
1.41 markus 3604: strerror(errno));
1.276 djm 3605: saved_errno = errno;
1.41 markus 3606: close(sock);
1.276 djm 3607: errno = saved_errno;
1.89 stevesk 3608: continue; /* fail -- try next */
1.41 markus 3609: }
1.336 millert 3610: if (cctx->ai->ai_family != AF_UNIX)
3611: set_nodelay(sock);
1.276 djm 3612: debug("connect_next: host %.100s ([%.100s]:%s) "
3613: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3614: cctx->ai = cctx->ai->ai_next;
3615: return sock;
3616: }
3617: return -1;
3618: }
1.41 markus 3619:
1.276 djm 3620: static void
3621: channel_connect_ctx_free(struct channel_connect *cctx)
3622: {
1.321 djm 3623: free(cctx->host);
1.336 millert 3624: if (cctx->aitop) {
3625: if (cctx->aitop->ai_family == AF_UNIX)
3626: free(cctx->aitop);
3627: else
3628: freeaddrinfo(cctx->aitop);
3629: }
1.329 tedu 3630: memset(cctx, 0, sizeof(*cctx));
1.276 djm 3631: }
3632:
1.357 dtucker 3633: /*
3634: * Return CONNECTING channel to remote host:port or local socket path,
3635: * passing back the failure reason if appropriate.
3636: */
1.276 djm 3637: static Channel *
1.357 dtucker 3638: connect_to_reason(const char *name, int port, char *ctype, char *rname,
3639: int *reason, const char **errmsg)
1.276 djm 3640: {
3641: struct addrinfo hints;
3642: int gaierr;
3643: int sock = -1;
3644: char strport[NI_MAXSERV];
3645: struct channel_connect cctx;
3646: Channel *c;
3647:
1.284 djm 3648: memset(&cctx, 0, sizeof(cctx));
1.336 millert 3649:
3650: if (port == PORT_STREAMLOCAL) {
3651: struct sockaddr_un *sunaddr;
3652: struct addrinfo *ai;
3653:
3654: if (strlen(name) > sizeof(sunaddr->sun_path)) {
3655: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
3656: return (NULL);
3657: }
3658:
3659: /*
3660: * Fake up a struct addrinfo for AF_UNIX connections.
3661: * channel_connect_ctx_free() must check ai_family
3662: * and use free() not freeaddirinfo() for AF_UNIX.
3663: */
3664: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
3665: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
3666: ai->ai_addr = (struct sockaddr *)(ai + 1);
3667: ai->ai_addrlen = sizeof(*sunaddr);
3668: ai->ai_family = AF_UNIX;
3669: ai->ai_socktype = SOCK_STREAM;
3670: ai->ai_protocol = PF_UNSPEC;
3671: sunaddr = (struct sockaddr_un *)ai->ai_addr;
3672: sunaddr->sun_family = AF_UNIX;
3673: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
3674: cctx.aitop = ai;
3675: } else {
3676: memset(&hints, 0, sizeof(hints));
3677: hints.ai_family = IPv4or6;
3678: hints.ai_socktype = SOCK_STREAM;
3679: snprintf(strport, sizeof strport, "%d", port);
1.357 dtucker 3680: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx.aitop))
3681: != 0) {
3682: if (errmsg != NULL)
3683: *errmsg = ssh_gai_strerror(gaierr);
3684: if (reason != NULL)
3685: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 3686: error("connect_to %.100s: unknown host (%s)", name,
3687: ssh_gai_strerror(gaierr));
3688: return NULL;
3689: }
1.41 markus 3690: }
1.276 djm 3691:
1.336 millert 3692: cctx.host = xstrdup(name);
1.276 djm 3693: cctx.port = port;
3694: cctx.ai = cctx.aitop;
3695:
3696: if ((sock = connect_next(&cctx)) == -1) {
3697: error("connect to %.100s port %d failed: %s",
1.336 millert 3698: name, port, strerror(errno));
1.276 djm 3699: channel_connect_ctx_free(&cctx);
3700: return NULL;
1.41 markus 3701: }
1.276 djm 3702: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
3703: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
3704: c->connect_ctx = cctx;
3705: return c;
1.41 markus 3706: }
1.99 markus 3707:
1.357 dtucker 3708: /* Return CONNECTING channel to remote host:port or local socket path */
3709: static Channel *
3710: connect_to(const char *name, int port, char *ctype, char *rname)
3711: {
3712: return connect_to_reason(name, port, ctype, rname, NULL, NULL);
3713: }
3714:
1.354 markus 3715: /*
3716: * returns either the newly connected channel or the downstream channel
3717: * that needs to deal with this connection.
3718: */
1.276 djm 3719: Channel *
1.333 markus 3720: channel_connect_by_listen_address(const char *listen_host,
3721: u_short listen_port, char *ctype, char *rname)
1.73 markus 3722: {
3723: int i;
1.99 markus 3724:
1.276 djm 3725: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3726: if (open_listen_match_tcpip(&permitted_opens[i], listen_host,
1.333 markus 3727: listen_port, 1)) {
1.354 markus 3728: if (permitted_opens[i].downstream)
3729: return permitted_opens[i].downstream;
1.99 markus 3730: return connect_to(
1.73 markus 3731: permitted_opens[i].host_to_connect,
1.276 djm 3732: permitted_opens[i].port_to_connect, ctype, rname);
3733: }
3734: }
1.74 markus 3735: error("WARNING: Server requests forwarding for unknown listen_port %d",
3736: listen_port);
1.276 djm 3737: return NULL;
1.73 markus 3738: }
3739:
1.336 millert 3740: Channel *
3741: channel_connect_by_listen_path(const char *path, char *ctype, char *rname)
3742: {
3743: int i;
3744:
3745: for (i = 0; i < num_permitted_opens; i++) {
3746: if (open_listen_match_streamlocal(&permitted_opens[i], path)) {
3747: return connect_to(
3748: permitted_opens[i].host_to_connect,
3749: permitted_opens[i].port_to_connect, ctype, rname);
3750: }
3751: }
3752: error("WARNING: Server requests forwarding for unknown path %.100s",
3753: path);
3754: return NULL;
3755: }
3756:
1.99 markus 3757: /* Check if connecting to that port is permitted and connect. */
1.276 djm 3758: Channel *
1.357 dtucker 3759: channel_connect_to_port(const char *host, u_short port, char *ctype,
3760: char *rname, int *reason, const char **errmsg)
1.99 markus 3761: {
1.257 dtucker 3762: int i, permit, permit_adm = 1;
1.99 markus 3763:
3764: permit = all_opens_permitted;
3765: if (!permit) {
3766: for (i = 0; i < num_permitted_opens; i++)
1.333 markus 3767: if (open_match(&permitted_opens[i], host, port)) {
1.99 markus 3768: permit = 1;
1.333 markus 3769: break;
3770: }
1.257 dtucker 3771: }
1.99 markus 3772:
1.257 dtucker 3773: if (num_adm_permitted_opens > 0) {
3774: permit_adm = 0;
3775: for (i = 0; i < num_adm_permitted_opens; i++)
1.333 markus 3776: if (open_match(&permitted_adm_opens[i], host, port)) {
1.257 dtucker 3777: permit_adm = 1;
1.333 markus 3778: break;
3779: }
1.99 markus 3780: }
1.257 dtucker 3781:
3782: if (!permit || !permit_adm) {
1.188 itojun 3783: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3784: "but the request was denied.", host, port);
1.357 dtucker 3785: if (reason != NULL)
3786: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 3787: return NULL;
1.99 markus 3788: }
1.357 dtucker 3789: return connect_to_reason(host, port, ctype, rname, reason, errmsg);
1.336 millert 3790: }
3791:
3792: /* Check if connecting to that path is permitted and connect. */
3793: Channel *
3794: channel_connect_to_path(const char *path, char *ctype, char *rname)
3795: {
3796: int i, permit, permit_adm = 1;
3797:
3798: permit = all_opens_permitted;
3799: if (!permit) {
3800: for (i = 0; i < num_permitted_opens; i++)
3801: if (open_match(&permitted_opens[i], path, PORT_STREAMLOCAL)) {
3802: permit = 1;
3803: break;
3804: }
3805: }
3806:
3807: if (num_adm_permitted_opens > 0) {
3808: permit_adm = 0;
3809: for (i = 0; i < num_adm_permitted_opens; i++)
3810: if (open_match(&permitted_adm_opens[i], path, PORT_STREAMLOCAL)) {
3811: permit_adm = 1;
3812: break;
3813: }
3814: }
3815:
3816: if (!permit || !permit_adm) {
3817: logit("Received request to connect to path %.100s, "
3818: "but the request was denied.", path);
3819: return NULL;
3820: }
3821: return connect_to(path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 3822: }
3823:
3824: void
3825: channel_send_window_changes(void)
3826: {
1.209 avsm 3827: u_int i;
1.204 djm 3828: struct winsize ws;
3829:
3830: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3831: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3832: channels[i]->type != SSH_CHANNEL_OPEN)
3833: continue;
3834: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3835: continue;
3836: channel_request_start(i, "window-change", 0);
1.238 deraadt 3837: packet_put_int((u_int)ws.ws_col);
3838: packet_put_int((u_int)ws.ws_row);
3839: packet_put_int((u_int)ws.ws_xpixel);
3840: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3841: packet_send();
3842: }
1.99 markus 3843: }
3844:
1.121 markus 3845: /* -- X11 forwarding */
1.1 deraadt 3846:
1.27 markus 3847: /*
3848: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3849: * Returns 0 and a suitable display number for the DISPLAY variable
3850: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3851: */
1.141 stevesk 3852: int
1.163 stevesk 3853: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3854: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3855: {
1.149 markus 3856: Channel *nc = NULL;
1.31 markus 3857: int display_number, sock;
3858: u_short port;
1.35 markus 3859: struct addrinfo hints, *ai, *aitop;
3860: char strport[NI_MAXSERV];
3861: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3862:
1.224 markus 3863: if (chanids == NULL)
3864: return -1;
3865:
1.33 markus 3866: for (display_number = x11_display_offset;
1.148 deraadt 3867: display_number < MAX_DISPLAYS;
3868: display_number++) {
1.25 markus 3869: port = 6000 + display_number;
1.35 markus 3870: memset(&hints, 0, sizeof(hints));
3871: hints.ai_family = IPv4or6;
1.163 stevesk 3872: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3873: hints.ai_socktype = SOCK_STREAM;
3874: snprintf(strport, sizeof strport, "%d", port);
3875: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3876: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3877: return -1;
1.25 markus 3878: }
1.35 markus 3879: for (ai = aitop; ai; ai = ai->ai_next) {
3880: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3881: continue;
1.300 dtucker 3882: sock = socket(ai->ai_family, ai->ai_socktype,
3883: ai->ai_protocol);
1.35 markus 3884: if (sock < 0) {
3885: error("socket: %.100s", strerror(errno));
1.203 markus 3886: freeaddrinfo(aitop);
1.141 stevesk 3887: return -1;
1.35 markus 3888: }
1.226 djm 3889: channel_set_reuseaddr(sock);
1.35 markus 3890: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3891: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3892: close(sock);
1.183 itojun 3893:
1.35 markus 3894: for (n = 0; n < num_socks; n++) {
3895: close(socks[n]);
3896: }
3897: num_socks = 0;
3898: break;
3899: }
3900: socks[num_socks++] = sock;
3901: if (num_socks == NUM_SOCKS)
3902: break;
1.25 markus 3903: }
1.83 stevesk 3904: freeaddrinfo(aitop);
1.35 markus 3905: if (num_socks > 0)
3906: break;
1.25 markus 3907: }
3908: if (display_number >= MAX_DISPLAYS) {
3909: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3910: return -1;
1.25 markus 3911: }
3912: /* Start listening for connections on the socket. */
1.35 markus 3913: for (n = 0; n < num_socks; n++) {
3914: sock = socks[n];
1.199 markus 3915: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3916: error("listen: %.100s", strerror(errno));
3917: close(sock);
1.141 stevesk 3918: return -1;
1.35 markus 3919: }
1.25 markus 3920: }
1.35 markus 3921:
3922: /* Allocate a channel for each socket. */
1.242 djm 3923: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3924: for (n = 0; n < num_socks; n++) {
3925: sock = socks[n];
1.149 markus 3926: nc = channel_new("x11 listener",
1.51 markus 3927: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3928: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3929: 0, "X11 inet listener", 1);
1.167 markus 3930: nc->single_connection = single_connection;
1.224 markus 3931: (*chanids)[n] = nc->self;
1.35 markus 3932: }
1.224 markus 3933: (*chanids)[n] = -1;
1.1 deraadt 3934:
1.141 stevesk 3935: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3936: *display_numberp = display_number;
3937: return (0);
1.1 deraadt 3938: }
3939:
1.127 itojun 3940: static int
1.77 markus 3941: connect_local_xsocket(u_int dnr)
1.1 deraadt 3942: {
1.25 markus 3943: int sock;
3944: struct sockaddr_un addr;
3945:
1.147 stevesk 3946: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3947: if (sock < 0)
3948: error("socket: %.100s", strerror(errno));
3949: memset(&addr, 0, sizeof(addr));
3950: addr.sun_family = AF_UNIX;
3951: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3952: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3953: return sock;
3954: close(sock);
1.25 markus 3955: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3956: return -1;
1.1 deraadt 3957: }
3958:
1.51 markus 3959: int
3960: x11_connect_display(void)
1.1 deraadt 3961: {
1.248 deraadt 3962: u_int display_number;
1.25 markus 3963: const char *display;
1.51 markus 3964: char buf[1024], *cp;
1.35 markus 3965: struct addrinfo hints, *ai, *aitop;
3966: char strport[NI_MAXSERV];
1.248 deraadt 3967: int gaierr, sock = 0;
1.25 markus 3968:
3969: /* Try to open a socket for the local X server. */
3970: display = getenv("DISPLAY");
3971: if (!display) {
3972: error("DISPLAY not set.");
1.51 markus 3973: return -1;
1.25 markus 3974: }
1.27 markus 3975: /*
3976: * Now we decode the value of the DISPLAY variable and make a
3977: * connection to the real X server.
3978: */
3979:
3980: /*
3981: * Check if it is a unix domain socket. Unix domain displays are in
3982: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3983: */
1.25 markus 3984: if (strncmp(display, "unix:", 5) == 0 ||
3985: display[0] == ':') {
3986: /* Connect to the unix domain socket. */
1.248 deraadt 3987: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3988: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3989: display);
1.51 markus 3990: return -1;
1.25 markus 3991: }
3992: /* Create a socket. */
3993: sock = connect_local_xsocket(display_number);
3994: if (sock < 0)
1.51 markus 3995: return -1;
1.25 markus 3996:
3997: /* OK, we now have a connection to the display. */
1.51 markus 3998: return sock;
1.25 markus 3999: }
1.27 markus 4000: /*
4001: * Connect to an inet socket. The DISPLAY value is supposedly
4002: * hostname:d[.s], where hostname may also be numeric IP address.
4003: */
1.145 stevesk 4004: strlcpy(buf, display, sizeof(buf));
1.25 markus 4005: cp = strchr(buf, ':');
4006: if (!cp) {
4007: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4008: return -1;
1.25 markus 4009: }
4010: *cp = 0;
1.27 markus 4011: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 4012: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4013: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4014: display);
1.51 markus 4015: return -1;
1.25 markus 4016: }
1.35 markus 4017:
4018: /* Look up the host address */
4019: memset(&hints, 0, sizeof(hints));
4020: hints.ai_family = IPv4or6;
4021: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4022: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4023: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4024: error("%.100s: unknown host. (%s)", buf,
4025: ssh_gai_strerror(gaierr));
1.51 markus 4026: return -1;
1.25 markus 4027: }
1.35 markus 4028: for (ai = aitop; ai; ai = ai->ai_next) {
4029: /* Create a socket. */
1.300 dtucker 4030: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4031: if (sock < 0) {
1.194 markus 4032: debug2("socket: %.100s", strerror(errno));
1.41 markus 4033: continue;
4034: }
4035: /* Connect it to the display. */
4036: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4037: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4038: 6000 + display_number, strerror(errno));
4039: close(sock);
4040: continue;
4041: }
4042: /* Success */
4043: break;
1.35 markus 4044: }
4045: freeaddrinfo(aitop);
4046: if (!ai) {
1.248 deraadt 4047: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 4048: strerror(errno));
1.51 markus 4049: return -1;
1.25 markus 4050: }
1.162 stevesk 4051: set_nodelay(sock);
1.51 markus 4052: return sock;
4053: }
4054:
4055: /*
1.27 markus 4056: * Requests forwarding of X11 connections, generates fake authentication
4057: * data, and enables authentication spoofing.
1.121 markus 4058: * This should be called in the client only.
1.27 markus 4059: */
1.49 markus 4060: void
1.215 djm 4061: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.311 djm 4062: const char *proto, const char *data, int want_reply)
1.1 deraadt 4063: {
1.77 markus 4064: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4065: u_int i, value;
1.25 markus 4066: char *new_data;
4067: int screen_number;
4068: const char *cp;
4069:
1.220 markus 4070: if (x11_saved_display == NULL)
4071: x11_saved_display = xstrdup(disp);
4072: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 4073: error("x11_request_forwarding_with_spoofing: different "
4074: "$DISPLAY already forwarded");
4075: return;
4076: }
4077:
1.266 djm 4078: cp = strchr(disp, ':');
1.25 markus 4079: if (cp)
4080: cp = strchr(cp, '.');
4081: if (cp)
1.245 deraadt 4082: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4083: else
4084: screen_number = 0;
4085:
1.219 djm 4086: if (x11_saved_proto == NULL) {
4087: /* Save protocol name. */
4088: x11_saved_proto = xstrdup(proto);
1.353 natano 4089:
4090: /* Extract real authentication data. */
1.219 djm 4091: x11_saved_data = xmalloc(data_len);
4092: for (i = 0; i < data_len; i++) {
4093: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4094: fatal("x11_request_forwarding: bad "
4095: "authentication data: %.100s", data);
4096: x11_saved_data[i] = value;
4097: }
4098: x11_saved_data_len = data_len;
1.353 natano 4099:
4100: /* Generate fake data of the same length. */
4101: x11_fake_data = xmalloc(data_len);
4102: arc4random_buf(x11_fake_data, data_len);
1.219 djm 4103: x11_fake_data_len = data_len;
1.25 markus 4104: }
4105:
4106: /* Convert the fake data into hex. */
1.219 djm 4107: new_data = tohex(x11_fake_data, data_len);
1.25 markus 4108:
4109: /* Send the request packet. */
1.358 djm 4110: channel_request_start(client_session_id, "x11-req", want_reply);
4111: packet_put_char(0); /* XXX bool single connection */
1.51 markus 4112: packet_put_cstring(proto);
4113: packet_put_cstring(new_data);
1.25 markus 4114: packet_put_int(screen_number);
4115: packet_send();
4116: packet_write_wait();
1.321 djm 4117: free(new_data);
1.1 deraadt 4118: }
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