Annotation of src/usr.bin/ssh/channels.c, Revision 1.352
1.352 ! deraadt 1: /* $OpenBSD: channels.c,v 1.351 2016/07/19 11:38:53 dtucker 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 "ssh1.h"
67: #include "ssh2.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. */
1.1 deraadt 117: } ForwardPermission;
118:
1.257 dtucker 119: /* List of all permitted host/port pairs to connect by the user. */
1.305 djm 120: static ForwardPermission *permitted_opens = NULL;
1.121 markus 121:
1.257 dtucker 122: /* List of all permitted host/port pairs to connect by the admin. */
1.305 djm 123: static ForwardPermission *permitted_adm_opens = NULL;
1.257 dtucker 124:
125: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 126: static int num_permitted_opens = 0;
1.257 dtucker 127:
128: /* Number of permitted host/port pair in the array permitted by the admin. */
129: static int num_adm_permitted_opens = 0;
130:
1.314 dtucker 131: /* special-case port number meaning allow any port */
132: #define FWD_PERMIT_ANY_PORT 0
133:
1.351 dtucker 134: /* special-case wildcard meaning allow any host */
135: #define FWD_PERMIT_ANY_HOST "*"
136:
1.27 markus 137: /*
138: * If this is true, all opens are permitted. This is the case on the server
139: * on which we have to trust the client anyway, and the user could do
140: * anything after logging in anyway.
141: */
1.1 deraadt 142: static int all_opens_permitted = 0;
143:
1.121 markus 144:
145: /* -- X11 forwarding */
146:
147: /* Maximum number of fake X11 displays to try. */
148: #define MAX_DISPLAYS 1000
149:
1.219 djm 150: /* Saved X11 local (client) display. */
151: static char *x11_saved_display = NULL;
152:
1.121 markus 153: /* Saved X11 authentication protocol name. */
154: static char *x11_saved_proto = NULL;
155:
156: /* Saved X11 authentication data. This is the real data. */
157: static char *x11_saved_data = NULL;
158: static u_int x11_saved_data_len = 0;
159:
1.347 djm 160: /* Deadline after which all X11 connections are refused */
161: static u_int x11_refuse_time;
162:
1.121 markus 163: /*
164: * Fake X11 authentication data. This is what the server will be sending us;
165: * we should replace any occurrences of this by the real data.
166: */
1.240 deraadt 167: static u_char *x11_fake_data = NULL;
1.121 markus 168: static u_int x11_fake_data_len;
169:
170:
171: /* -- agent forwarding */
172:
173: #define NUM_SOCKS 10
174:
1.82 markus 175: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 176: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 177:
1.121 markus 178: /* helper */
1.127 itojun 179: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 180:
1.276 djm 181: /* non-blocking connect helpers */
182: static int connect_next(struct channel_connect *);
183: static void channel_connect_ctx_free(struct channel_connect *);
184:
1.121 markus 185: /* -- channel core */
1.41 markus 186:
187: Channel *
1.229 markus 188: channel_by_id(int id)
1.41 markus 189: {
190: Channel *c;
1.113 markus 191:
1.209 avsm 192: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 193: logit("channel_by_id: %d: bad id", id);
1.41 markus 194: return NULL;
195: }
1.113 markus 196: c = channels[id];
197: if (c == NULL) {
1.229 markus 198: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 199: return NULL;
200: }
201: return c;
1.55 markus 202: }
203:
1.27 markus 204: /*
1.229 markus 205: * Returns the channel if it is allowed to receive protocol messages.
206: * Private channels, like listening sockets, may not receive messages.
207: */
208: Channel *
209: channel_lookup(int id)
210: {
211: Channel *c;
212:
213: if ((c = channel_by_id(id)) == NULL)
214: return (NULL);
215:
1.237 deraadt 216: switch (c->type) {
1.229 markus 217: case SSH_CHANNEL_X11_OPEN:
218: case SSH_CHANNEL_LARVAL:
219: case SSH_CHANNEL_CONNECTING:
220: case SSH_CHANNEL_DYNAMIC:
221: case SSH_CHANNEL_OPENING:
222: case SSH_CHANNEL_OPEN:
223: case SSH_CHANNEL_INPUT_DRAINING:
224: case SSH_CHANNEL_OUTPUT_DRAINING:
1.323 dtucker 225: case SSH_CHANNEL_ABANDONED:
1.229 markus 226: return (c);
227: }
228: logit("Non-public channel %d, type %d.", id, c->type);
229: return (NULL);
230: }
231:
232: /*
1.55 markus 233: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 234: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 235: */
1.127 itojun 236: static void
1.71 markus 237: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 238: int extusage, int nonblock, int is_tty)
1.1 deraadt 239: {
1.25 markus 240: /* Update the maximum file descriptor value. */
1.352 ! deraadt 241: channel_max_fd = MAXIMUM(channel_max_fd, rfd);
! 242: channel_max_fd = MAXIMUM(channel_max_fd, wfd);
! 243: channel_max_fd = MAXIMUM(channel_max_fd, efd);
1.84 markus 244:
1.298 dtucker 245: if (rfd != -1)
246: fcntl(rfd, F_SETFD, FD_CLOEXEC);
247: if (wfd != -1 && wfd != rfd)
248: fcntl(wfd, F_SETFD, FD_CLOEXEC);
249: if (efd != -1 && efd != rfd && efd != wfd)
250: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 251:
1.52 markus 252: c->rfd = rfd;
253: c->wfd = wfd;
254: c->sock = (rfd == wfd) ? rfd : -1;
255: c->efd = efd;
256: c->extended_usage = extusage;
1.71 markus 257:
1.282 dtucker 258: if ((c->isatty = is_tty) != 0)
1.194 markus 259: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 260:
1.71 markus 261: /* enable nonblocking mode */
262: if (nonblock) {
263: if (rfd != -1)
264: set_nonblock(rfd);
265: if (wfd != -1)
266: set_nonblock(wfd);
267: if (efd != -1)
268: set_nonblock(efd);
269: }
1.52 markus 270: }
271:
272: /*
273: * Allocate a new channel object and set its type and socket. This will cause
274: * remote_name to be freed.
275: */
1.113 markus 276: Channel *
1.52 markus 277: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 278: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 279: {
1.209 avsm 280: int found;
281: u_int i;
1.52 markus 282: Channel *c;
1.25 markus 283:
284: /* Do initial allocation if this is the first call. */
285: if (channels_alloc == 0) {
286: channels_alloc = 10;
1.242 djm 287: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 288: for (i = 0; i < channels_alloc; i++)
1.113 markus 289: channels[i] = NULL;
1.25 markus 290: }
291: /* Try to find a free slot where to put the new channel. */
292: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 293: if (channels[i] == NULL) {
1.25 markus 294: /* Found a free slot. */
1.209 avsm 295: found = (int)i;
1.25 markus 296: break;
297: }
1.209 avsm 298: if (found < 0) {
1.27 markus 299: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 300: found = channels_alloc;
1.179 markus 301: if (channels_alloc > 10000)
302: fatal("channel_new: internal error: channels_alloc %d "
303: "too big.", channels_alloc);
1.342 deraadt 304: channels = xreallocarray(channels, channels_alloc + 10,
1.243 djm 305: sizeof(Channel *));
1.195 markus 306: channels_alloc += 10;
1.70 markus 307: debug2("channel: expanding %d", channels_alloc);
1.25 markus 308: for (i = found; i < channels_alloc; i++)
1.113 markus 309: channels[i] = NULL;
1.25 markus 310: }
1.113 markus 311: /* Initialize and return new channel. */
1.242 djm 312: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 313: buffer_init(&c->input);
314: buffer_init(&c->output);
1.41 markus 315: buffer_init(&c->extended);
1.293 djm 316: c->path = NULL;
1.312 djm 317: c->listening_addr = NULL;
318: c->listening_port = 0;
1.159 markus 319: c->ostate = CHAN_OUTPUT_OPEN;
320: c->istate = CHAN_INPUT_OPEN;
321: c->flags = 0;
1.281 djm 322: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.317 djm 323: c->notbefore = 0;
1.25 markus 324: c->self = found;
325: c->type = type;
1.41 markus 326: c->ctype = ctype;
1.51 markus 327: c->local_window = window;
328: c->local_window_max = window;
329: c->local_consumed = 0;
330: c->local_maxpacket = maxpack;
1.25 markus 331: c->remote_id = -1;
1.190 markus 332: c->remote_name = xstrdup(remote_name);
1.41 markus 333: c->remote_window = 0;
334: c->remote_maxpacket = 0;
1.133 markus 335: c->force_drain = 0;
1.149 markus 336: c->single_connection = 0;
1.131 markus 337: c->detach_user = NULL;
1.225 djm 338: c->detach_close = 0;
1.275 djm 339: c->open_confirm = NULL;
340: c->open_confirm_ctx = NULL;
1.65 markus 341: c->input_filter = NULL;
1.231 reyk 342: c->output_filter = NULL;
1.280 djm 343: c->filter_ctx = NULL;
344: c->filter_cleanup = NULL;
1.302 djm 345: c->ctl_chan = -1;
346: c->mux_rcb = NULL;
347: c->mux_ctx = NULL;
1.304 djm 348: c->mux_pause = 0;
1.299 markus 349: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 350: TAILQ_INIT(&c->status_confirms);
1.25 markus 351: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 352: return c;
1.1 deraadt 353: }
1.52 markus 354:
1.132 markus 355: static int
356: channel_find_maxfd(void)
357: {
1.209 avsm 358: u_int i;
359: int max = 0;
1.132 markus 360: Channel *c;
361:
362: for (i = 0; i < channels_alloc; i++) {
363: c = channels[i];
364: if (c != NULL) {
1.352 ! deraadt 365: max = MAXIMUM(max, c->rfd);
! 366: max = MAXIMUM(max, c->wfd);
! 367: max = MAXIMUM(max, c->efd);
1.132 markus 368: }
369: }
370: return max;
371: }
372:
373: int
374: channel_close_fd(int *fdp)
375: {
376: int ret = 0, fd = *fdp;
377:
378: if (fd != -1) {
379: ret = close(fd);
380: *fdp = -1;
381: if (fd == channel_max_fd)
382: channel_max_fd = channel_find_maxfd();
383: }
384: return ret;
385: }
386:
1.52 markus 387: /* Close all channel fd/socket. */
1.127 itojun 388: static void
1.52 markus 389: channel_close_fds(Channel *c)
390: {
1.132 markus 391: channel_close_fd(&c->sock);
392: channel_close_fd(&c->rfd);
393: channel_close_fd(&c->wfd);
394: channel_close_fd(&c->efd);
1.121 markus 395: }
396:
397: /* Free the channel and close its fd/socket. */
398: void
399: channel_free(Channel *c)
400: {
401: char *s;
1.209 avsm 402: u_int i, n;
1.275 djm 403: struct channel_confirm *cc;
1.121 markus 404:
405: for (n = 0, i = 0; i < channels_alloc; i++)
406: if (channels[i])
407: n++;
1.209 avsm 408: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 409: c->remote_name ? c->remote_name : "???", n);
410:
411: s = channel_open_message();
1.194 markus 412: debug3("channel %d: status: %s", c->self, s);
1.321 djm 413: free(s);
1.121 markus 414:
415: if (c->sock != -1)
416: shutdown(c->sock, SHUT_RDWR);
417: channel_close_fds(c);
418: buffer_free(&c->input);
419: buffer_free(&c->output);
420: buffer_free(&c->extended);
1.321 djm 421: free(c->remote_name);
422: c->remote_name = NULL;
423: free(c->path);
424: c->path = NULL;
425: free(c->listening_addr);
426: c->listening_addr = NULL;
1.275 djm 427: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
428: if (cc->abandon_cb != NULL)
429: cc->abandon_cb(c, cc->ctx);
430: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 431: explicit_bzero(cc, sizeof(*cc));
1.321 djm 432: free(cc);
1.275 djm 433: }
1.280 djm 434: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
435: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 436: channels[c->self] = NULL;
1.321 djm 437: free(c);
1.121 markus 438: }
439:
440: void
1.126 markus 441: channel_free_all(void)
1.121 markus 442: {
1.209 avsm 443: u_int i;
1.121 markus 444:
1.126 markus 445: for (i = 0; i < channels_alloc; i++)
446: if (channels[i] != NULL)
447: channel_free(channels[i]);
1.131 markus 448: }
449:
1.121 markus 450: /*
451: * Closes the sockets/fds of all channels. This is used to close extra file
452: * descriptors after a fork.
453: */
454: void
1.142 itojun 455: channel_close_all(void)
1.121 markus 456: {
1.209 avsm 457: u_int i;
1.121 markus 458:
459: for (i = 0; i < channels_alloc; i++)
460: if (channels[i] != NULL)
461: channel_close_fds(channels[i]);
462: }
463:
464: /*
1.131 markus 465: * Stop listening to channels.
466: */
467: void
468: channel_stop_listening(void)
469: {
1.209 avsm 470: u_int i;
1.131 markus 471: Channel *c;
472:
473: for (i = 0; i < channels_alloc; i++) {
474: c = channels[i];
475: if (c != NULL) {
476: switch (c->type) {
477: case SSH_CHANNEL_AUTH_SOCKET:
478: case SSH_CHANNEL_PORT_LISTENER:
479: case SSH_CHANNEL_RPORT_LISTENER:
480: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 481: case SSH_CHANNEL_UNIX_LISTENER:
482: case SSH_CHANNEL_RUNIX_LISTENER:
1.132 markus 483: channel_close_fd(&c->sock);
1.131 markus 484: channel_free(c);
485: break;
486: }
487: }
488: }
489: }
490:
491: /*
1.121 markus 492: * Returns true if no channel has too much buffered data, and false if one or
493: * more channel is overfull.
494: */
495: int
1.142 itojun 496: channel_not_very_much_buffered_data(void)
1.121 markus 497: {
498: u_int i;
499: Channel *c;
500:
501: for (i = 0; i < channels_alloc; i++) {
502: c = channels[i];
503: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 504: #if 0
505: if (!compat20 &&
506: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 507: debug2("channel %d: big input buffer %d",
1.121 markus 508: c->self, buffer_len(&c->input));
509: return 0;
510: }
1.136 markus 511: #endif
1.121 markus 512: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 513: debug2("channel %d: big output buffer %u > %u",
1.136 markus 514: c->self, buffer_len(&c->output),
515: packet_get_maxsize());
1.121 markus 516: return 0;
517: }
518: }
519: }
520: return 1;
521: }
522:
523: /* Returns true if any channel is still open. */
524: int
1.142 itojun 525: channel_still_open(void)
1.121 markus 526: {
1.209 avsm 527: u_int i;
1.121 markus 528: Channel *c;
529:
530: for (i = 0; i < channels_alloc; i++) {
531: c = channels[i];
532: if (c == NULL)
533: continue;
534: switch (c->type) {
535: case SSH_CHANNEL_X11_LISTENER:
536: case SSH_CHANNEL_PORT_LISTENER:
537: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 538: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 539: case SSH_CHANNEL_CLOSED:
540: case SSH_CHANNEL_AUTH_SOCKET:
541: case SSH_CHANNEL_DYNAMIC:
542: case SSH_CHANNEL_CONNECTING:
543: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 544: case SSH_CHANNEL_ABANDONED:
1.336 millert 545: case SSH_CHANNEL_UNIX_LISTENER:
546: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 547: continue;
548: case SSH_CHANNEL_LARVAL:
549: if (!compat20)
550: fatal("cannot happen: SSH_CHANNEL_LARVAL");
551: continue;
552: case SSH_CHANNEL_OPENING:
553: case SSH_CHANNEL_OPEN:
554: case SSH_CHANNEL_X11_OPEN:
1.302 djm 555: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 556: return 1;
557: case SSH_CHANNEL_INPUT_DRAINING:
558: case SSH_CHANNEL_OUTPUT_DRAINING:
559: if (!compat13)
560: fatal("cannot happen: OUT_DRAIN");
561: return 1;
562: default:
563: fatal("channel_still_open: bad channel type %d", c->type);
564: /* NOTREACHED */
565: }
566: }
567: return 0;
568: }
569:
570: /* Returns the id of an open channel suitable for keepaliving */
571: int
1.142 itojun 572: channel_find_open(void)
1.121 markus 573: {
1.209 avsm 574: u_int i;
1.121 markus 575: Channel *c;
576:
577: for (i = 0; i < channels_alloc; i++) {
578: c = channels[i];
1.206 djm 579: if (c == NULL || c->remote_id < 0)
1.121 markus 580: continue;
581: switch (c->type) {
582: case SSH_CHANNEL_CLOSED:
583: case SSH_CHANNEL_DYNAMIC:
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:
588: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 589: case SSH_CHANNEL_OPENING:
590: case SSH_CHANNEL_CONNECTING:
591: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 592: case SSH_CHANNEL_ABANDONED:
1.336 millert 593: case SSH_CHANNEL_UNIX_LISTENER:
594: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 595: continue;
596: case SSH_CHANNEL_LARVAL:
597: case SSH_CHANNEL_AUTH_SOCKET:
598: case SSH_CHANNEL_OPEN:
599: case SSH_CHANNEL_X11_OPEN:
600: return i;
601: case SSH_CHANNEL_INPUT_DRAINING:
602: case SSH_CHANNEL_OUTPUT_DRAINING:
603: if (!compat13)
604: fatal("cannot happen: OUT_DRAIN");
605: return i;
606: default:
607: fatal("channel_find_open: bad channel type %d", c->type);
608: /* NOTREACHED */
609: }
610: }
611: return -1;
612: }
613:
614:
615: /*
616: * Returns a message describing the currently open forwarded connections,
617: * suitable for sending to the client. The message contains crlf pairs for
618: * newlines.
619: */
620: char *
1.142 itojun 621: channel_open_message(void)
1.121 markus 622: {
623: Buffer buffer;
624: Channel *c;
625: char buf[1024], *cp;
1.209 avsm 626: u_int i;
1.121 markus 627:
628: buffer_init(&buffer);
629: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
630: buffer_append(&buffer, buf, strlen(buf));
631: for (i = 0; i < channels_alloc; i++) {
632: c = channels[i];
633: if (c == NULL)
634: continue;
635: switch (c->type) {
636: case SSH_CHANNEL_X11_LISTENER:
637: case SSH_CHANNEL_PORT_LISTENER:
638: case SSH_CHANNEL_RPORT_LISTENER:
639: case SSH_CHANNEL_CLOSED:
640: case SSH_CHANNEL_AUTH_SOCKET:
641: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 642: case SSH_CHANNEL_ABANDONED:
1.302 djm 643: case SSH_CHANNEL_MUX_CLIENT:
644: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 645: case SSH_CHANNEL_UNIX_LISTENER:
646: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 647: continue;
648: case SSH_CHANNEL_LARVAL:
649: case SSH_CHANNEL_OPENING:
650: case SSH_CHANNEL_CONNECTING:
651: case SSH_CHANNEL_DYNAMIC:
652: case SSH_CHANNEL_OPEN:
653: case SSH_CHANNEL_X11_OPEN:
654: case SSH_CHANNEL_INPUT_DRAINING:
655: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 656: snprintf(buf, sizeof buf,
1.348 djm 657: " #%d %.300s (t%d r%d i%u/%d o%u/%d fd %d/%d cc %d)\r\n",
1.121 markus 658: c->self, c->remote_name,
659: c->type, c->remote_id,
660: c->istate, buffer_len(&c->input),
661: c->ostate, buffer_len(&c->output),
1.302 djm 662: c->rfd, c->wfd, c->ctl_chan);
1.121 markus 663: buffer_append(&buffer, buf, strlen(buf));
664: continue;
665: default:
666: fatal("channel_open_message: bad channel type %d", c->type);
667: /* NOTREACHED */
668: }
669: }
670: buffer_append(&buffer, "\0", 1);
1.337 djm 671: cp = xstrdup((char *)buffer_ptr(&buffer));
1.121 markus 672: buffer_free(&buffer);
673: return cp;
674: }
675:
676: void
677: channel_send_open(int id)
678: {
679: Channel *c = channel_lookup(id);
1.180 deraadt 680:
1.121 markus 681: if (c == NULL) {
1.188 itojun 682: logit("channel_send_open: %d: bad id", id);
1.121 markus 683: return;
684: }
1.184 markus 685: debug2("channel %d: send open", id);
1.121 markus 686: packet_start(SSH2_MSG_CHANNEL_OPEN);
687: packet_put_cstring(c->ctype);
688: packet_put_int(c->self);
689: packet_put_int(c->local_window);
690: packet_put_int(c->local_maxpacket);
691: packet_send();
692: }
693:
694: void
1.184 markus 695: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 696: {
1.184 markus 697: Channel *c = channel_lookup(id);
1.180 deraadt 698:
1.121 markus 699: if (c == NULL) {
1.188 itojun 700: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 701: return;
702: }
1.204 djm 703: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 704: packet_start(SSH2_MSG_CHANNEL_REQUEST);
705: packet_put_int(c->remote_id);
706: packet_put_cstring(service);
707: packet_put_char(wantconfirm);
708: }
1.241 deraadt 709:
1.121 markus 710: void
1.275 djm 711: channel_register_status_confirm(int id, channel_confirm_cb *cb,
712: channel_confirm_abandon_cb *abandon_cb, void *ctx)
713: {
714: struct channel_confirm *cc;
715: Channel *c;
716:
717: if ((c = channel_lookup(id)) == NULL)
718: fatal("channel_register_expect: %d: bad id", id);
719:
1.327 djm 720: cc = xcalloc(1, sizeof(*cc));
1.275 djm 721: cc->cb = cb;
722: cc->abandon_cb = abandon_cb;
723: cc->ctx = ctx;
724: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
725: }
726:
727: void
1.304 djm 728: channel_register_open_confirm(int id, channel_open_fn *fn, void *ctx)
1.121 markus 729: {
730: Channel *c = channel_lookup(id);
1.180 deraadt 731:
1.121 markus 732: if (c == NULL) {
1.287 stevesk 733: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 734: return;
735: }
1.275 djm 736: c->open_confirm = fn;
737: c->open_confirm_ctx = ctx;
1.121 markus 738: }
1.241 deraadt 739:
1.121 markus 740: void
1.225 djm 741: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 742: {
1.229 markus 743: Channel *c = channel_by_id(id);
1.180 deraadt 744:
1.121 markus 745: if (c == NULL) {
1.188 itojun 746: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 747: return;
748: }
1.131 markus 749: c->detach_user = fn;
1.225 djm 750: c->detach_close = do_close;
1.121 markus 751: }
1.241 deraadt 752:
1.121 markus 753: void
754: channel_cancel_cleanup(int id)
755: {
1.229 markus 756: Channel *c = channel_by_id(id);
1.180 deraadt 757:
1.121 markus 758: if (c == NULL) {
1.188 itojun 759: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 760: return;
1.52 markus 761: }
1.131 markus 762: c->detach_user = NULL;
1.225 djm 763: c->detach_close = 0;
1.121 markus 764: }
1.241 deraadt 765:
1.121 markus 766: void
1.231 reyk 767: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 768: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 769: {
770: Channel *c = channel_lookup(id);
1.180 deraadt 771:
1.121 markus 772: if (c == NULL) {
1.188 itojun 773: logit("channel_register_filter: %d: bad id", id);
1.121 markus 774: return;
1.52 markus 775: }
1.231 reyk 776: c->input_filter = ifn;
777: c->output_filter = ofn;
1.279 djm 778: c->filter_ctx = ctx;
1.280 djm 779: c->filter_cleanup = cfn;
1.52 markus 780: }
781:
1.49 markus 782: void
1.121 markus 783: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 784: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 785: {
1.121 markus 786: Channel *c = channel_lookup(id);
1.180 deraadt 787:
1.121 markus 788: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
789: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 790: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 791: c->type = SSH_CHANNEL_OPEN;
1.168 markus 792: c->local_window = c->local_window_max = window_max;
1.121 markus 793: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
794: packet_put_int(c->remote_id);
795: packet_put_int(c->local_window);
796: packet_send();
1.1 deraadt 797: }
798:
1.27 markus 799: /*
1.41 markus 800: * 'channel_pre*' are called just before select() to add any bits relevant to
801: * channels in the select bitmasks.
802: */
803: /*
804: * 'channel_post*': perform any appropriate operations for channels which
805: * have events pending.
1.27 markus 806: */
1.237 deraadt 807: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 808: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
809: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
810:
1.259 stevesk 811: /* ARGSUSED */
1.127 itojun 812: static void
1.237 deraadt 813: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 814: {
815: FD_SET(c->sock, readset);
816: }
817:
1.259 stevesk 818: /* ARGSUSED */
1.127 itojun 819: static void
1.237 deraadt 820: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 821: {
822: debug3("channel %d: waiting for connection", c->self);
823: FD_SET(c->sock, writeset);
824: }
825:
1.127 itojun 826: static void
1.237 deraadt 827: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 828: {
829: if (buffer_len(&c->input) < packet_get_maxsize())
830: FD_SET(c->sock, readset);
831: if (buffer_len(&c->output) > 0)
832: FD_SET(c->sock, writeset);
833: }
1.1 deraadt 834:
1.127 itojun 835: static void
1.237 deraadt 836: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 837: {
1.157 markus 838: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 839:
1.44 markus 840: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 841: limit > 0 &&
1.250 djm 842: buffer_len(&c->input) < limit &&
843: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 844: FD_SET(c->rfd, readset);
845: if (c->ostate == CHAN_OUTPUT_OPEN ||
846: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
847: if (buffer_len(&c->output) > 0) {
848: FD_SET(c->wfd, writeset);
849: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 850: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 851: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
852: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 853: else
854: chan_obuf_empty(c);
1.44 markus 855: }
856: }
857: /** XXX check close conditions, too */
1.277 markus 858: if (compat20 && c->efd != -1 &&
859: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 860: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
861: buffer_len(&c->extended) > 0)
862: FD_SET(c->efd, writeset);
1.306 djm 863: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
864: (c->extended_usage == CHAN_EXTENDED_READ ||
865: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 866: buffer_len(&c->extended) < c->remote_window)
867: FD_SET(c->efd, readset);
868: }
1.204 djm 869: /* XXX: What about efd? races? */
1.44 markus 870: }
871:
1.259 stevesk 872: /* ARGSUSED */
1.127 itojun 873: static void
1.237 deraadt 874: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 875: {
876: if (buffer_len(&c->input) == 0) {
877: packet_start(SSH_MSG_CHANNEL_CLOSE);
878: packet_put_int(c->remote_id);
879: packet_send();
880: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 881: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 882: }
883: }
884:
1.259 stevesk 885: /* ARGSUSED */
1.127 itojun 886: static void
1.237 deraadt 887: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 888: {
889: if (buffer_len(&c->output) == 0)
1.113 markus 890: chan_mark_dead(c);
1.49 markus 891: else
1.41 markus 892: FD_SET(c->sock, writeset);
893: }
894:
895: /*
896: * This is a special state for X11 authentication spoofing. An opened X11
897: * connection (when authentication spoofing is being done) remains in this
898: * state until the first packet has been completely read. The authentication
899: * data in that packet is then substituted by the real data if it matches the
900: * fake data, and the channel is put into normal mode.
1.51 markus 901: * XXX All this happens at the client side.
1.121 markus 902: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 903: */
1.127 itojun 904: static int
1.121 markus 905: x11_open_helper(Buffer *b)
1.1 deraadt 906: {
1.77 markus 907: u_char *ucp;
908: u_int proto_len, data_len;
1.25 markus 909:
1.347 djm 910: /* Is this being called after the refusal deadline? */
911: if (x11_refuse_time != 0 && (u_int)monotime() >= x11_refuse_time) {
912: verbose("Rejected X11 connection after ForwardX11Timeout "
913: "expired");
914: return -1;
915: }
916:
1.41 markus 917: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 918: if (buffer_len(b) < 12)
1.41 markus 919: return 0;
920:
921: /* Parse the lengths of variable-length fields. */
1.155 stevesk 922: ucp = buffer_ptr(b);
1.41 markus 923: if (ucp[0] == 0x42) { /* Byte order MSB first. */
924: proto_len = 256 * ucp[6] + ucp[7];
925: data_len = 256 * ucp[8] + ucp[9];
926: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
927: proto_len = ucp[6] + 256 * ucp[7];
928: data_len = ucp[8] + 256 * ucp[9];
929: } else {
1.194 markus 930: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 931: ucp[0]);
1.41 markus 932: return -1;
933: }
934:
935: /* Check if the whole packet is in buffer. */
1.121 markus 936: if (buffer_len(b) <
1.41 markus 937: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
938: return 0;
939:
940: /* Check if authentication protocol matches. */
941: if (proto_len != strlen(x11_saved_proto) ||
942: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 943: debug2("X11 connection uses different authentication protocol.");
1.41 markus 944: return -1;
945: }
946: /* Check if authentication data matches our fake data. */
947: if (data_len != x11_fake_data_len ||
1.308 djm 948: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.41 markus 949: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 950: debug2("X11 auth data does not match fake data.");
1.41 markus 951: return -1;
952: }
953: /* Check fake data length */
954: if (x11_fake_data_len != x11_saved_data_len) {
955: error("X11 fake_data_len %d != saved_data_len %d",
956: x11_fake_data_len, x11_saved_data_len);
957: return -1;
958: }
959: /*
960: * Received authentication protocol and data match
961: * our fake data. Substitute the fake data with real
962: * data.
963: */
964: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
965: x11_saved_data, x11_saved_data_len);
966: return 1;
967: }
968:
1.127 itojun 969: static void
1.237 deraadt 970: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 971: {
1.121 markus 972: int ret = x11_open_helper(&c->output);
1.180 deraadt 973:
1.41 markus 974: if (ret == 1) {
975: /* Start normal processing for the channel. */
976: c->type = SSH_CHANNEL_OPEN;
1.47 markus 977: channel_pre_open_13(c, readset, writeset);
1.41 markus 978: } else if (ret == -1) {
979: /*
980: * We have received an X11 connection that has bad
981: * authentication information.
982: */
1.188 itojun 983: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 984: buffer_clear(&c->input);
985: buffer_clear(&c->output);
1.132 markus 986: channel_close_fd(&c->sock);
1.41 markus 987: c->sock = -1;
988: c->type = SSH_CHANNEL_CLOSED;
989: packet_start(SSH_MSG_CHANNEL_CLOSE);
990: packet_put_int(c->remote_id);
991: packet_send();
992: }
993: }
1.25 markus 994:
1.127 itojun 995: static void
1.237 deraadt 996: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 997: {
1.121 markus 998: int ret = x11_open_helper(&c->output);
1.133 markus 999:
1000: /* c->force_drain = 1; */
1001:
1.41 markus 1002: if (ret == 1) {
1003: c->type = SSH_CHANNEL_OPEN;
1.157 markus 1004: channel_pre_open(c, readset, writeset);
1.41 markus 1005: } else if (ret == -1) {
1.188 itojun 1006: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 1007: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 1008: chan_read_failed(c);
1009: buffer_clear(&c->input);
1010: chan_ibuf_empty(c);
1011: buffer_clear(&c->output);
1012: /* for proto v1, the peer will send an IEOF */
1013: if (compat20)
1014: chan_write_failed(c);
1015: else
1016: c->type = SSH_CHANNEL_OPEN;
1.194 markus 1017: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1018: }
1019: }
1.25 markus 1020:
1.302 djm 1021: static void
1022: channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1023: {
1.304 djm 1024: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.302 djm 1025: buffer_check_alloc(&c->input, CHAN_RBUF))
1026: FD_SET(c->rfd, readset);
1027: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1028: /* clear buffer immediately (discard any partial packet) */
1029: buffer_clear(&c->input);
1030: chan_ibuf_empty(c);
1031: /* Start output drain. XXX just kill chan? */
1032: chan_rcvd_oclose(c);
1033: }
1034: if (c->ostate == CHAN_OUTPUT_OPEN ||
1035: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1036: if (buffer_len(&c->output) > 0)
1037: FD_SET(c->wfd, writeset);
1038: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1039: chan_obuf_empty(c);
1040: }
1041: }
1042:
1.104 markus 1043: /* try to decode a socks4 header */
1.259 stevesk 1044: /* ARGSUSED */
1.127 itojun 1045: static int
1.237 deraadt 1046: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 1047: {
1.181 markus 1048: char *p, *host;
1.292 djm 1049: u_int len, have, i, found, need;
1.148 deraadt 1050: char username[256];
1.103 markus 1051: struct {
1052: u_int8_t version;
1053: u_int8_t command;
1054: u_int16_t dest_port;
1.104 markus 1055: struct in_addr dest_addr;
1.103 markus 1056: } s4_req, s4_rsp;
1057:
1.104 markus 1058: debug2("channel %d: decode socks4", c->self);
1.109 markus 1059:
1060: have = buffer_len(&c->input);
1061: len = sizeof(s4_req);
1062: if (have < len)
1063: return 0;
1.337 djm 1064: p = (char *)buffer_ptr(&c->input);
1.292 djm 1065:
1066: need = 1;
1067: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1068: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1069: debug2("channel %d: socks4a request", c->self);
1070: /* ... and needs an extra string (the hostname) */
1071: need = 2;
1072: }
1073: /* Check for terminating NUL on the string(s) */
1.109 markus 1074: for (found = 0, i = len; i < have; i++) {
1075: if (p[i] == '\0') {
1.292 djm 1076: found++;
1077: if (found == need)
1078: break;
1.109 markus 1079: }
1080: if (i > 1024) {
1081: /* the peer is probably sending garbage */
1082: debug("channel %d: decode socks4: too long",
1083: c->self);
1084: return -1;
1085: }
1086: }
1.292 djm 1087: if (found < need)
1.109 markus 1088: return 0;
1.103 markus 1089: buffer_get(&c->input, (char *)&s4_req.version, 1);
1090: buffer_get(&c->input, (char *)&s4_req.command, 1);
1091: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1092: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1093: have = buffer_len(&c->input);
1.337 djm 1094: p = (char *)buffer_ptr(&c->input);
1.331 djm 1095: if (memchr(p, '\0', have) == NULL)
1096: fatal("channel %d: decode socks4: user not nul terminated",
1097: c->self);
1.103 markus 1098: len = strlen(p);
1.106 markus 1099: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1100: len++; /* trailing '\0' */
1.103 markus 1101: if (len > have)
1.104 markus 1102: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1103: c->self, len, have);
1104: strlcpy(username, p, sizeof(username));
1105: buffer_consume(&c->input, len);
1106:
1.321 djm 1107: free(c->path);
1108: c->path = NULL;
1.292 djm 1109: if (need == 1) { /* SOCKS4: one string */
1110: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1111: c->path = xstrdup(host);
1.292 djm 1112: } else { /* SOCKS4A: two strings */
1113: have = buffer_len(&c->input);
1.337 djm 1114: p = (char *)buffer_ptr(&c->input);
1.292 djm 1115: len = strlen(p);
1116: debug2("channel %d: decode socks4a: host %s/%d",
1117: c->self, p, len);
1118: len++; /* trailing '\0' */
1119: if (len > have)
1120: fatal("channel %d: decode socks4a: len %d > have %d",
1121: c->self, len, have);
1.293 djm 1122: if (len > NI_MAXHOST) {
1.292 djm 1123: error("channel %d: hostname \"%.100s\" too long",
1124: c->self, p);
1125: return -1;
1126: }
1.293 djm 1127: c->path = xstrdup(p);
1.292 djm 1128: buffer_consume(&c->input, len);
1129: }
1.103 markus 1130: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1131:
1.194 markus 1132: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1133: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1134:
1.104 markus 1135: if (s4_req.command != 1) {
1.292 djm 1136: debug("channel %d: cannot handle: %s cn %d",
1137: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1138: return -1;
1.103 markus 1139: }
1.104 markus 1140: s4_rsp.version = 0; /* vn: 0 for reply */
1141: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1142: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1143: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1144: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1145: return 1;
1146: }
1147:
1.193 markus 1148: /* try to decode a socks5 header */
1149: #define SSH_SOCKS5_AUTHDONE 0x1000
1150: #define SSH_SOCKS5_NOAUTH 0x00
1151: #define SSH_SOCKS5_IPV4 0x01
1152: #define SSH_SOCKS5_DOMAIN 0x03
1153: #define SSH_SOCKS5_IPV6 0x04
1154: #define SSH_SOCKS5_CONNECT 0x01
1155: #define SSH_SOCKS5_SUCCESS 0x00
1156:
1.259 stevesk 1157: /* ARGSUSED */
1.193 markus 1158: static int
1.237 deraadt 1159: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1160: {
1161: struct {
1162: u_int8_t version;
1163: u_int8_t command;
1164: u_int8_t reserved;
1165: u_int8_t atyp;
1166: } s5_req, s5_rsp;
1167: u_int16_t dest_port;
1.324 djm 1168: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1169: u_char *p;
1.252 djm 1170: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1171:
1172: debug2("channel %d: decode socks5", c->self);
1173: p = buffer_ptr(&c->input);
1174: if (p[0] != 0x05)
1175: return -1;
1176: have = buffer_len(&c->input);
1177: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1178: /* format: ver | nmethods | methods */
1.198 djm 1179: if (have < 2)
1.193 markus 1180: return 0;
1181: nmethods = p[1];
1182: if (have < nmethods + 2)
1183: return 0;
1184: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1185: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1186: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1187: found = 1;
1188: break;
1189: }
1190: }
1191: if (!found) {
1192: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1193: c->self);
1194: return -1;
1195: }
1196: buffer_consume(&c->input, nmethods + 2);
1197: buffer_put_char(&c->output, 0x05); /* version */
1198: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1199: FD_SET(c->sock, writeset);
1200: c->flags |= SSH_SOCKS5_AUTHDONE;
1201: debug2("channel %d: socks5 auth done", c->self);
1202: return 0; /* need more */
1203: }
1204: debug2("channel %d: socks5 post auth", c->self);
1205: if (have < sizeof(s5_req)+1)
1206: return 0; /* need more */
1.247 deraadt 1207: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1208: if (s5_req.version != 0x05 ||
1209: s5_req.command != SSH_SOCKS5_CONNECT ||
1210: s5_req.reserved != 0x00) {
1.194 markus 1211: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1212: return -1;
1213: }
1.213 deraadt 1214: switch (s5_req.atyp){
1.193 markus 1215: case SSH_SOCKS5_IPV4:
1216: addrlen = 4;
1217: af = AF_INET;
1218: break;
1219: case SSH_SOCKS5_DOMAIN:
1220: addrlen = p[sizeof(s5_req)];
1221: af = -1;
1222: break;
1223: case SSH_SOCKS5_IPV6:
1224: addrlen = 16;
1225: af = AF_INET6;
1226: break;
1227: default:
1.194 markus 1228: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1229: return -1;
1230: }
1.252 djm 1231: need = sizeof(s5_req) + addrlen + 2;
1232: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1233: need++;
1234: if (have < need)
1.193 markus 1235: return 0;
1236: buffer_consume(&c->input, sizeof(s5_req));
1237: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1238: buffer_consume(&c->input, 1); /* host string length */
1.324 djm 1239: buffer_get(&c->input, &dest_addr, addrlen);
1.193 markus 1240: buffer_get(&c->input, (char *)&dest_port, 2);
1241: dest_addr[addrlen] = '\0';
1.321 djm 1242: free(c->path);
1243: c->path = NULL;
1.293 djm 1244: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1245: if (addrlen >= NI_MAXHOST) {
1.293 djm 1246: error("channel %d: dynamic request: socks5 hostname "
1247: "\"%.100s\" too long", c->self, dest_addr);
1248: return -1;
1249: }
1250: c->path = xstrdup(dest_addr);
1251: } else {
1252: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1253: return -1;
1254: c->path = xstrdup(ntop);
1255: }
1.193 markus 1256: c->host_port = ntohs(dest_port);
1.198 djm 1257:
1.194 markus 1258: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1259: c->self, c->path, c->host_port, s5_req.command);
1260:
1261: s5_rsp.version = 0x05;
1262: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1263: s5_rsp.reserved = 0; /* ignored */
1264: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1265: dest_port = 0; /* ignored */
1266:
1.246 deraadt 1267: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1.325 djm 1268: buffer_put_int(&c->output, ntohl(INADDR_ANY)); /* bind address */
1.246 deraadt 1269: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1270: return 1;
1.301 dtucker 1271: }
1272:
1273: Channel *
1.302 djm 1274: channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
1275: int in, int out)
1.301 dtucker 1276: {
1277: Channel *c;
1278:
1279: debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
1280: port_to_connect);
1281:
1282: c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
1283: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1284: 0, "stdio-forward", /*nonblock*/0);
1285:
1286: c->path = xstrdup(host_to_connect);
1287: c->host_port = port_to_connect;
1288: c->listening_port = 0;
1289: c->force_drain = 1;
1290:
1291: channel_register_fds(c, in, out, -1, 0, 1, 0);
1292: port_open_helper(c, "direct-tcpip");
1293:
1294: return c;
1.193 markus 1295: }
1296:
1.104 markus 1297: /* dynamic port forwarding */
1.127 itojun 1298: static void
1.237 deraadt 1299: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1300: {
1301: u_char *p;
1.217 djm 1302: u_int have;
1303: int ret;
1.103 markus 1304:
1.104 markus 1305: have = buffer_len(&c->input);
1306: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1307: /* buffer_dump(&c->input); */
1.104 markus 1308: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1309: if (have < 3) {
1.104 markus 1310: /* need more */
1311: FD_SET(c->sock, readset);
1312: return;
1313: }
1314: /* try to guess the protocol */
1315: p = buffer_ptr(&c->input);
1316: switch (p[0]) {
1317: case 0x04:
1318: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1319: break;
1320: case 0x05:
1321: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1322: break;
1323: default:
1324: ret = -1;
1325: break;
1326: }
1327: if (ret < 0) {
1.113 markus 1328: chan_mark_dead(c);
1.104 markus 1329: } else if (ret == 0) {
1330: debug2("channel %d: pre_dynamic: need more", c->self);
1331: /* need more */
1332: FD_SET(c->sock, readset);
1333: } else {
1334: /* switch to the next state */
1335: c->type = SSH_CHANNEL_OPENING;
1336: port_open_helper(c, "direct-tcpip");
1337: }
1.103 markus 1338: }
1339:
1.41 markus 1340: /* This is our fake X11 server socket. */
1.259 stevesk 1341: /* ARGSUSED */
1.127 itojun 1342: static void
1.237 deraadt 1343: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1344: {
1.113 markus 1345: Channel *nc;
1.285 djm 1346: struct sockaddr_storage addr;
1.320 markus 1347: int newsock, oerrno;
1.41 markus 1348: socklen_t addrlen;
1.85 markus 1349: char buf[16384], *remote_ipaddr;
1.51 markus 1350: int remote_port;
1.25 markus 1351:
1.41 markus 1352: if (FD_ISSET(c->sock, readset)) {
1353: debug("X11 connection requested.");
1354: addrlen = sizeof(addr);
1.285 djm 1355: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1356: if (c->single_connection) {
1.320 markus 1357: oerrno = errno;
1.194 markus 1358: debug2("single_connection: closing X11 listener.");
1.149 markus 1359: channel_close_fd(&c->sock);
1360: chan_mark_dead(c);
1.320 markus 1361: errno = oerrno;
1.149 markus 1362: }
1.41 markus 1363: if (newsock < 0) {
1.320 markus 1364: if (errno != EINTR && errno != EWOULDBLOCK &&
1365: errno != ECONNABORTED)
1366: error("accept: %.100s", strerror(errno));
1.317 djm 1367: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1368: c->notbefore = monotime() + 1;
1.41 markus 1369: return;
1370: }
1.162 stevesk 1371: set_nodelay(newsock);
1.85 markus 1372: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1373: remote_port = get_peer_port(newsock);
1.41 markus 1374: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1375: remote_ipaddr, remote_port);
1.51 markus 1376:
1.113 markus 1377: nc = channel_new("accepted x11 socket",
1.51 markus 1378: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1379: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1380: if (compat20) {
1381: packet_start(SSH2_MSG_CHANNEL_OPEN);
1382: packet_put_cstring("x11");
1.113 markus 1383: packet_put_int(nc->self);
1.149 markus 1384: packet_put_int(nc->local_window_max);
1385: packet_put_int(nc->local_maxpacket);
1.85 markus 1386: /* originator ipaddr and port */
1387: packet_put_cstring(remote_ipaddr);
1.57 markus 1388: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1389: debug2("ssh2 x11 bug compat mode");
1.57 markus 1390: } else {
1391: packet_put_int(remote_port);
1392: }
1.51 markus 1393: packet_send();
1394: } else {
1395: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1396: packet_put_int(nc->self);
1.121 markus 1397: if (packet_get_protocol_flags() &
1398: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1399: packet_put_cstring(buf);
1.51 markus 1400: packet_send();
1401: }
1.321 djm 1402: free(remote_ipaddr);
1.41 markus 1403: }
1404: }
1.25 markus 1405:
1.127 itojun 1406: static void
1.103 markus 1407: port_open_helper(Channel *c, char *rtype)
1408: {
1409: char buf[1024];
1.328 djm 1410: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1411: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1412: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1413: int remote_port = get_peer_port(c->sock);
1.303 djm 1414:
1415: if (remote_port == -1) {
1416: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1417: free(remote_ipaddr);
1.303 djm 1418: remote_ipaddr = xstrdup("127.0.0.1");
1419: remote_port = 65535;
1420: }
1.103 markus 1421:
1422: snprintf(buf, sizeof buf,
1423: "%s: listening port %d for %.100s port %d, "
1.328 djm 1424: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1425: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1426: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1427:
1.321 djm 1428: free(c->remote_name);
1.103 markus 1429: c->remote_name = xstrdup(buf);
1430:
1431: if (compat20) {
1432: packet_start(SSH2_MSG_CHANNEL_OPEN);
1433: packet_put_cstring(rtype);
1434: packet_put_int(c->self);
1435: packet_put_int(c->local_window_max);
1436: packet_put_int(c->local_maxpacket);
1.336 millert 1437: if (strcmp(rtype, "direct-tcpip") == 0) {
1.103 markus 1438: /* target host, port */
1439: packet_put_cstring(c->path);
1440: packet_put_int(c->host_port);
1.336 millert 1441: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1442: /* target path */
1443: packet_put_cstring(c->path);
1444: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1445: /* listen path */
1446: packet_put_cstring(c->path);
1.103 markus 1447: } else {
1448: /* listen address, port */
1449: packet_put_cstring(c->path);
1.328 djm 1450: packet_put_int(local_port);
1.103 markus 1451: }
1.336 millert 1452: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1453: /* reserved for future owner/mode info */
1454: packet_put_cstring("");
1455: } else {
1456: /* originator host and port */
1457: packet_put_cstring(remote_ipaddr);
1458: packet_put_int((u_int)remote_port);
1459: }
1.103 markus 1460: packet_send();
1461: } else {
1462: packet_start(SSH_MSG_PORT_OPEN);
1463: packet_put_int(c->self);
1464: packet_put_cstring(c->path);
1465: packet_put_int(c->host_port);
1.121 markus 1466: if (packet_get_protocol_flags() &
1467: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1468: packet_put_cstring(c->remote_name);
1469: packet_send();
1470: }
1.321 djm 1471: free(remote_ipaddr);
1.328 djm 1472: free(local_ipaddr);
1.103 markus 1473: }
1474:
1.226 djm 1475: static void
1476: channel_set_reuseaddr(int fd)
1477: {
1478: int on = 1;
1479:
1480: /*
1481: * Set socket options.
1482: * Allow local port reuse in TIME_WAIT.
1483: */
1484: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1485: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1.347 djm 1486: }
1487:
1488: void
1489: channel_set_x11_refuse_time(u_int refuse_time)
1490: {
1491: x11_refuse_time = refuse_time;
1.226 djm 1492: }
1493:
1.41 markus 1494: /*
1495: * This socket is listening for connections to a forwarded TCP/IP port.
1496: */
1.259 stevesk 1497: /* ARGSUSED */
1.127 itojun 1498: static void
1.237 deraadt 1499: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1500: {
1.103 markus 1501: Channel *nc;
1.285 djm 1502: struct sockaddr_storage addr;
1.113 markus 1503: int newsock, nextstate;
1.41 markus 1504: socklen_t addrlen;
1.103 markus 1505: char *rtype;
1.73 markus 1506:
1.41 markus 1507: if (FD_ISSET(c->sock, readset)) {
1508: debug("Connection to port %d forwarding "
1509: "to %.100s port %d requested.",
1510: c->listening_port, c->path, c->host_port);
1.103 markus 1511:
1.137 markus 1512: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1513: nextstate = SSH_CHANNEL_OPENING;
1514: rtype = "forwarded-tcpip";
1.336 millert 1515: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1516: nextstate = SSH_CHANNEL_OPENING;
1517: rtype = "forwarded-streamlocal@openssh.com";
1518: } else if (c->host_port == PORT_STREAMLOCAL) {
1519: nextstate = SSH_CHANNEL_OPENING;
1520: rtype = "direct-streamlocal@openssh.com";
1521: } else if (c->host_port == 0) {
1522: nextstate = SSH_CHANNEL_DYNAMIC;
1523: rtype = "dynamic-tcpip";
1.137 markus 1524: } else {
1.336 millert 1525: nextstate = SSH_CHANNEL_OPENING;
1526: rtype = "direct-tcpip";
1.137 markus 1527: }
1.103 markus 1528:
1.41 markus 1529: addrlen = sizeof(addr);
1.285 djm 1530: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1531: if (newsock < 0) {
1.320 markus 1532: if (errno != EINTR && errno != EWOULDBLOCK &&
1533: errno != ECONNABORTED)
1534: error("accept: %.100s", strerror(errno));
1.317 djm 1535: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1536: c->notbefore = monotime() + 1;
1.41 markus 1537: return;
1538: }
1.336 millert 1539: if (c->host_port != PORT_STREAMLOCAL)
1540: set_nodelay(newsock);
1.190 markus 1541: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1542: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1543: nc->listening_port = c->listening_port;
1544: nc->host_port = c->host_port;
1.293 djm 1545: if (c->path != NULL)
1546: nc->path = xstrdup(c->path);
1.103 markus 1547:
1.299 markus 1548: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1549: port_open_helper(nc, rtype);
1.41 markus 1550: }
1551: }
1.25 markus 1552:
1.41 markus 1553: /*
1554: * This is the authentication agent socket listening for connections from
1555: * clients.
1556: */
1.259 stevesk 1557: /* ARGSUSED */
1.127 itojun 1558: static void
1.237 deraadt 1559: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1560: {
1.113 markus 1561: Channel *nc;
1562: int newsock;
1.285 djm 1563: struct sockaddr_storage addr;
1.41 markus 1564: socklen_t addrlen;
1.25 markus 1565:
1.41 markus 1566: if (FD_ISSET(c->sock, readset)) {
1567: addrlen = sizeof(addr);
1.285 djm 1568: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1569: if (newsock < 0) {
1.317 djm 1570: error("accept from auth socket: %.100s",
1571: strerror(errno));
1572: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1573: c->notbefore = monotime() + 1;
1.41 markus 1574: return;
1575: }
1.113 markus 1576: nc = channel_new("accepted auth socket",
1.73 markus 1577: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1578: c->local_window_max, c->local_maxpacket,
1.190 markus 1579: 0, "accepted auth socket", 1);
1.73 markus 1580: if (compat20) {
1581: packet_start(SSH2_MSG_CHANNEL_OPEN);
1582: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1583: packet_put_int(nc->self);
1.73 markus 1584: packet_put_int(c->local_window_max);
1585: packet_put_int(c->local_maxpacket);
1586: } else {
1587: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1588: packet_put_int(nc->self);
1.73 markus 1589: }
1.41 markus 1590: packet_send();
1591: }
1592: }
1.25 markus 1593:
1.259 stevesk 1594: /* ARGSUSED */
1.127 itojun 1595: static void
1.237 deraadt 1596: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1597: {
1.276 djm 1598: int err = 0, sock;
1.129 stevesk 1599: socklen_t sz = sizeof(err);
1.114 markus 1600:
1.75 markus 1601: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1602: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1603: err = errno;
1604: error("getsockopt SO_ERROR failed");
1605: }
1606: if (err == 0) {
1.276 djm 1607: debug("channel %d: connected to %s port %d",
1608: c->self, c->connect_ctx.host, c->connect_ctx.port);
1609: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1610: c->type = SSH_CHANNEL_OPEN;
1611: if (compat20) {
1612: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1613: packet_put_int(c->remote_id);
1614: packet_put_int(c->self);
1615: packet_put_int(c->local_window);
1616: packet_put_int(c->local_maxpacket);
1617: } else {
1618: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1619: packet_put_int(c->remote_id);
1620: packet_put_int(c->self);
1621: }
1.75 markus 1622: } else {
1.276 djm 1623: debug("channel %d: connection failed: %s",
1.114 markus 1624: c->self, strerror(err));
1.276 djm 1625: /* Try next address, if any */
1626: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1627: close(c->sock);
1628: c->sock = c->rfd = c->wfd = sock;
1629: channel_max_fd = channel_find_maxfd();
1630: return;
1631: }
1632: /* Exhausted all addresses */
1633: error("connect_to %.100s port %d: failed.",
1634: c->connect_ctx.host, c->connect_ctx.port);
1635: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1636: if (compat20) {
1637: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1638: packet_put_int(c->remote_id);
1639: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1640: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1641: packet_put_cstring(strerror(err));
1642: packet_put_cstring("");
1643: }
1.75 markus 1644: } else {
1.114 markus 1645: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1646: packet_put_int(c->remote_id);
1.75 markus 1647: }
1.114 markus 1648: chan_mark_dead(c);
1.75 markus 1649: }
1.114 markus 1650: packet_send();
1.75 markus 1651: }
1652: }
1653:
1.259 stevesk 1654: /* ARGSUSED */
1.127 itojun 1655: static int
1.237 deraadt 1656: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1657: {
1.214 markus 1658: char buf[CHAN_RBUF];
1.41 markus 1659: int len;
1.25 markus 1660:
1.118 markus 1661: if (c->rfd != -1 &&
1.41 markus 1662: FD_ISSET(c->rfd, readset)) {
1663: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1664: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1665: return 1;
1.41 markus 1666: if (len <= 0) {
1.194 markus 1667: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1668: c->self, c->rfd, len);
1.104 markus 1669: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1670: debug2("channel %d: not open", c->self);
1.113 markus 1671: chan_mark_dead(c);
1.103 markus 1672: return -1;
1.104 markus 1673: } else if (compat13) {
1.158 markus 1674: buffer_clear(&c->output);
1.41 markus 1675: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1676: debug2("channel %d: input draining.", c->self);
1.25 markus 1677: } else {
1.41 markus 1678: chan_read_failed(c);
1.25 markus 1679: }
1.41 markus 1680: return -1;
1681: }
1.143 deraadt 1682: if (c->input_filter != NULL) {
1.66 markus 1683: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1684: debug2("channel %d: filter stops", c->self);
1.65 markus 1685: chan_read_failed(c);
1686: }
1.228 reyk 1687: } else if (c->datagram) {
1688: buffer_put_string(&c->input, buf, len);
1.65 markus 1689: } else {
1690: buffer_append(&c->input, buf, len);
1691: }
1.41 markus 1692: }
1693: return 1;
1694: }
1.241 deraadt 1695:
1.259 stevesk 1696: /* ARGSUSED */
1.127 itojun 1697: static int
1.237 deraadt 1698: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1699: {
1.95 markus 1700: struct termios tio;
1.231 reyk 1701: u_char *data = NULL, *buf;
1.309 djm 1702: u_int dlen, olen = 0;
1.41 markus 1703: int len;
1.25 markus 1704:
1.41 markus 1705: /* Send buffered output data to the socket. */
1.118 markus 1706: if (c->wfd != -1 &&
1.41 markus 1707: FD_ISSET(c->wfd, writeset) &&
1708: buffer_len(&c->output) > 0) {
1.309 djm 1709: olen = buffer_len(&c->output);
1.231 reyk 1710: if (c->output_filter != NULL) {
1711: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1712: debug2("channel %d: filter stops", c->self);
1.232 reyk 1713: if (c->type != SSH_CHANNEL_OPEN)
1714: chan_mark_dead(c);
1715: else
1716: chan_write_failed(c);
1717: return -1;
1.231 reyk 1718: }
1719: } else if (c->datagram) {
1720: buf = data = buffer_get_string(&c->output, &dlen);
1721: } else {
1722: buf = data = buffer_ptr(&c->output);
1723: dlen = buffer_len(&c->output);
1724: }
1725:
1.228 reyk 1726: if (c->datagram) {
1727: /* ignore truncated writes, datagrams might get lost */
1.231 reyk 1728: len = write(c->wfd, buf, dlen);
1.321 djm 1729: free(data);
1.228 reyk 1730: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1731: return 1;
1732: if (len <= 0) {
1733: if (c->type != SSH_CHANNEL_OPEN)
1734: chan_mark_dead(c);
1735: else
1736: chan_write_failed(c);
1737: return -1;
1738: }
1.309 djm 1739: goto out;
1.228 reyk 1740: }
1.231 reyk 1741:
1742: len = write(c->wfd, buf, dlen);
1.53 markus 1743: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1744: return 1;
1.41 markus 1745: if (len <= 0) {
1.104 markus 1746: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1747: debug2("channel %d: not open", c->self);
1.113 markus 1748: chan_mark_dead(c);
1.104 markus 1749: return -1;
1750: } else if (compat13) {
1.158 markus 1751: buffer_clear(&c->output);
1.194 markus 1752: debug2("channel %d: input draining.", c->self);
1.41 markus 1753: c->type = SSH_CHANNEL_INPUT_DRAINING;
1754: } else {
1755: chan_write_failed(c);
1756: }
1757: return -1;
1.91 markus 1758: }
1.231 reyk 1759: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1760: if (tcgetattr(c->wfd, &tio) == 0 &&
1761: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1762: /*
1763: * Simulate echo to reduce the impact of
1.96 markus 1764: * traffic analysis. We need to match the
1.95 markus 1765: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1766: * (4 byte channel id + buf)
1.91 markus 1767: */
1.95 markus 1768: packet_send_ignore(4 + len);
1.91 markus 1769: packet_send();
1770: }
1.25 markus 1771: }
1.41 markus 1772: buffer_consume(&c->output, len);
1.44 markus 1773: }
1.309 djm 1774: out:
1775: if (compat20 && olen > 0)
1776: c->local_consumed += olen - buffer_len(&c->output);
1.44 markus 1777: return 1;
1778: }
1.241 deraadt 1779:
1.127 itojun 1780: static int
1.237 deraadt 1781: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1782: {
1.214 markus 1783: char buf[CHAN_RBUF];
1.44 markus 1784: int len;
1785:
1.45 markus 1786: /** XXX handle drain efd, too */
1.44 markus 1787: if (c->efd != -1) {
1788: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1789: FD_ISSET(c->efd, writeset) &&
1790: buffer_len(&c->extended) > 0) {
1791: len = write(c->efd, buffer_ptr(&c->extended),
1792: buffer_len(&c->extended));
1.70 markus 1793: debug2("channel %d: written %d to efd %d",
1.44 markus 1794: c->self, len, c->efd);
1.93 markus 1795: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1796: return 1;
1797: if (len <= 0) {
1798: debug2("channel %d: closing write-efd %d",
1799: c->self, c->efd);
1.132 markus 1800: channel_close_fd(&c->efd);
1.93 markus 1801: } else {
1.44 markus 1802: buffer_consume(&c->extended, len);
1803: c->local_consumed += len;
1804: }
1.306 djm 1805: } else if (c->efd != -1 &&
1806: (c->extended_usage == CHAN_EXTENDED_READ ||
1807: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 1808: FD_ISSET(c->efd, readset)) {
1809: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1810: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1811: c->self, len, c->efd);
1.93 markus 1812: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1813: return 1;
1814: if (len <= 0) {
1815: debug2("channel %d: closing read-efd %d",
1.45 markus 1816: c->self, c->efd);
1.132 markus 1817: channel_close_fd(&c->efd);
1.93 markus 1818: } else {
1.306 djm 1819: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
1820: debug3("channel %d: discard efd",
1821: c->self);
1822: } else
1823: buffer_append(&c->extended, buf, len);
1.93 markus 1824: }
1.44 markus 1825: }
1826: }
1827: return 1;
1828: }
1.241 deraadt 1829:
1.259 stevesk 1830: /* ARGSUSED */
1.127 itojun 1831: static int
1.93 markus 1832: channel_check_window(Channel *c)
1.44 markus 1833: {
1.104 markus 1834: if (c->type == SSH_CHANNEL_OPEN &&
1835: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1836: ((c->local_window_max - c->local_window >
1.269 markus 1837: c->local_maxpacket*3) ||
1838: c->local_window < c->local_window_max/2) &&
1.44 markus 1839: c->local_consumed > 0) {
1840: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1841: packet_put_int(c->remote_id);
1842: packet_put_int(c->local_consumed);
1843: packet_send();
1.70 markus 1844: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1845: c->self, c->local_window,
1846: c->local_consumed);
1847: c->local_window += c->local_consumed;
1848: c->local_consumed = 0;
1.1 deraadt 1849: }
1.41 markus 1850: return 1;
1.1 deraadt 1851: }
1852:
1.127 itojun 1853: static void
1.237 deraadt 1854: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1855: {
1856: channel_handle_rfd(c, readset, writeset);
1857: channel_handle_wfd(c, readset, writeset);
1.157 markus 1858: if (!compat20)
1.137 markus 1859: return;
1.44 markus 1860: channel_handle_efd(c, readset, writeset);
1.93 markus 1861: channel_check_window(c);
1.44 markus 1862: }
1863:
1.302 djm 1864: static u_int
1865: read_mux(Channel *c, u_int need)
1866: {
1867: char buf[CHAN_RBUF];
1868: int len;
1869: u_int rlen;
1870:
1871: if (buffer_len(&c->input) < need) {
1872: rlen = need - buffer_len(&c->input);
1.352 ! deraadt 1873: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.349 naddy 1874: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1875: return buffer_len(&c->input);
1.302 djm 1876: if (len <= 0) {
1.349 naddy 1877: debug2("channel %d: ctl read<=0 rfd %d len %d",
1878: c->self, c->rfd, len);
1879: chan_read_failed(c);
1880: return 0;
1.302 djm 1881: } else
1882: buffer_append(&c->input, buf, len);
1883: }
1884: return buffer_len(&c->input);
1885: }
1886:
1887: static void
1888: channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1889: {
1890: u_int need;
1891: ssize_t len;
1892:
1893: if (!compat20)
1894: fatal("%s: entered with !compat20", __func__);
1895:
1.304 djm 1896: if (c->rfd != -1 && !c->mux_pause && FD_ISSET(c->rfd, readset) &&
1.302 djm 1897: (c->istate == CHAN_INPUT_OPEN ||
1898: c->istate == CHAN_INPUT_WAIT_DRAIN)) {
1899: /*
1900: * Don't not read past the precise end of packets to
1901: * avoid disrupting fd passing.
1902: */
1903: if (read_mux(c, 4) < 4) /* read header */
1904: return;
1905: need = get_u32(buffer_ptr(&c->input));
1906: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1907: if (need > CHANNEL_MUX_MAX_PACKET) {
1908: debug2("channel %d: packet too big %u > %u",
1909: c->self, CHANNEL_MUX_MAX_PACKET, need);
1910: chan_rcvd_oclose(c);
1911: return;
1912: }
1913: if (read_mux(c, need + 4) < need + 4) /* read body */
1914: return;
1915: if (c->mux_rcb(c) != 0) {
1916: debug("channel %d: mux_rcb failed", c->self);
1917: chan_mark_dead(c);
1918: return;
1919: }
1920: }
1921:
1922: if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) &&
1923: buffer_len(&c->output) > 0) {
1924: len = write(c->wfd, buffer_ptr(&c->output),
1925: buffer_len(&c->output));
1926: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1927: return;
1928: if (len <= 0) {
1929: chan_mark_dead(c);
1930: return;
1931: }
1932: buffer_consume(&c->output, len);
1933: }
1934: }
1935:
1936: static void
1937: channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset)
1938: {
1939: Channel *nc;
1940: struct sockaddr_storage addr;
1941: socklen_t addrlen;
1942: int newsock;
1943: uid_t euid;
1944: gid_t egid;
1945:
1946: if (!FD_ISSET(c->sock, readset))
1947: return;
1948:
1949: debug("multiplexing control connection");
1950:
1951: /*
1952: * Accept connection on control socket
1953: */
1954: memset(&addr, 0, sizeof(addr));
1955: addrlen = sizeof(addr);
1956: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
1957: &addrlen)) == -1) {
1958: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 1959: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1960: c->notbefore = monotime() + 1;
1.302 djm 1961: return;
1962: }
1963:
1964: if (getpeereid(newsock, &euid, &egid) < 0) {
1965: error("%s getpeereid failed: %s", __func__,
1966: strerror(errno));
1967: close(newsock);
1968: return;
1969: }
1970: if ((euid != 0) && (getuid() != euid)) {
1971: error("multiplex uid mismatch: peer euid %u != uid %u",
1972: (u_int)euid, (u_int)getuid());
1973: close(newsock);
1974: return;
1975: }
1976: nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT,
1977: newsock, newsock, -1, c->local_window_max,
1978: c->local_maxpacket, 0, "mux-control", 1);
1979: nc->mux_rcb = c->mux_rcb;
1980: debug3("%s: new mux channel %d fd %d", __func__,
1981: nc->self, nc->sock);
1982: /* establish state */
1983: nc->mux_rcb(nc);
1984: /* mux state transitions must not elicit protocol messages */
1985: nc->flags |= CHAN_LOCAL;
1986: }
1987:
1.259 stevesk 1988: /* ARGSUSED */
1.127 itojun 1989: static void
1.237 deraadt 1990: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1991: {
1.41 markus 1992: int len;
1.180 deraadt 1993:
1.41 markus 1994: /* Send buffered output data to the socket. */
1995: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1996: len = write(c->sock, buffer_ptr(&c->output),
1997: buffer_len(&c->output));
1998: if (len <= 0)
1.158 markus 1999: buffer_clear(&c->output);
1.41 markus 2000: else
2001: buffer_consume(&c->output, len);
2002: }
2003: }
1.25 markus 2004:
1.127 itojun 2005: static void
1.44 markus 2006: channel_handler_init_20(void)
2007: {
1.157 markus 2008: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 2009: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 2010: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 2011: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.336 millert 2012: channel_pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2013: channel_pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
1.51 markus 2014: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 2015: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 2016: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2017: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.302 djm 2018: channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2019: channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
1.44 markus 2020:
1.157 markus 2021: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 2022: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 2023: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.336 millert 2024: channel_post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2025: channel_post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
1.51 markus 2026: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 2027: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 2028: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2029: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.302 djm 2030: channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2031: channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.44 markus 2032: }
2033:
1.127 itojun 2034: static void
1.41 markus 2035: channel_handler_init_13(void)
2036: {
2037: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
2038: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
2039: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2040: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2041: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2042: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
2043: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 2044: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2045: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 2046:
1.157 markus 2047: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 2048: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2049: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2050: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2051: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 2052: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2053: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2054: }
1.25 markus 2055:
1.127 itojun 2056: static void
1.41 markus 2057: channel_handler_init_15(void)
2058: {
1.157 markus 2059: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 2060: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 2061: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2062: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2063: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 2064: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2065: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 2066:
1.41 markus 2067: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2068: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2069: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 2070: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 2071: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2072: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2073: }
1.27 markus 2074:
1.127 itojun 2075: static void
1.41 markus 2076: channel_handler_init(void)
2077: {
2078: int i;
1.180 deraadt 2079:
1.148 deraadt 2080: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 2081: channel_pre[i] = NULL;
2082: channel_post[i] = NULL;
2083: }
1.44 markus 2084: if (compat20)
2085: channel_handler_init_20();
2086: else if (compat13)
1.41 markus 2087: channel_handler_init_13();
2088: else
2089: channel_handler_init_15();
2090: }
1.25 markus 2091:
1.140 markus 2092: /* gc dead channels */
2093: static void
2094: channel_garbage_collect(Channel *c)
2095: {
2096: if (c == NULL)
2097: return;
2098: if (c->detach_user != NULL) {
1.225 djm 2099: if (!chan_is_dead(c, c->detach_close))
1.140 markus 2100: return;
1.194 markus 2101: debug2("channel %d: gc: notify user", c->self);
1.140 markus 2102: c->detach_user(c->self, NULL);
2103: /* if we still have a callback */
2104: if (c->detach_user != NULL)
2105: return;
1.194 markus 2106: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2107: }
2108: if (!chan_is_dead(c, 1))
2109: return;
1.194 markus 2110: debug2("channel %d: garbage collecting", c->self);
1.140 markus 2111: channel_free(c);
2112: }
2113:
1.127 itojun 2114: static void
1.317 djm 2115: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset,
2116: time_t *unpause_secs)
1.41 markus 2117: {
2118: static int did_init = 0;
1.299 markus 2119: u_int i, oalloc;
1.41 markus 2120: Channel *c;
1.317 djm 2121: time_t now;
1.25 markus 2122:
1.41 markus 2123: if (!did_init) {
2124: channel_handler_init();
2125: did_init = 1;
2126: }
1.322 dtucker 2127: now = monotime();
1.317 djm 2128: if (unpause_secs != NULL)
2129: *unpause_secs = 0;
1.299 markus 2130: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 2131: c = channels[i];
2132: if (c == NULL)
1.41 markus 2133: continue;
1.299 markus 2134: if (c->delayed) {
2135: if (ftab == channel_pre)
2136: c->delayed = 0;
2137: else
2138: continue;
2139: }
1.317 djm 2140: if (ftab[c->type] != NULL) {
2141: /*
2142: * Run handlers that are not paused.
2143: */
2144: if (c->notbefore <= now)
2145: (*ftab[c->type])(c, readset, writeset);
2146: else if (unpause_secs != NULL) {
2147: /*
2148: * Collect the time that the earliest
2149: * channel comes off pause.
2150: */
2151: debug3("%s: chan %d: skip for %d more seconds",
2152: __func__, c->self,
2153: (int)(c->notbefore - now));
2154: if (*unpause_secs == 0 ||
2155: (c->notbefore - now) < *unpause_secs)
2156: *unpause_secs = c->notbefore - now;
2157: }
2158: }
1.140 markus 2159: channel_garbage_collect(c);
1.1 deraadt 2160: }
1.317 djm 2161: if (unpause_secs != NULL && *unpause_secs != 0)
2162: debug3("%s: first channel unpauses in %d seconds",
2163: __func__, (int)*unpause_secs);
1.1 deraadt 2164: }
2165:
1.121 markus 2166: /*
2167: * Allocate/update select bitmasks and add any bits relevant to channels in
2168: * select bitmasks.
2169: */
1.49 markus 2170: void
1.100 markus 2171: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.318 djm 2172: u_int *nallocp, time_t *minwait_secs, int rekeying)
1.41 markus 2173: {
1.243 djm 2174: u_int n, sz, nfdset;
1.84 markus 2175:
1.352 ! deraadt 2176: n = MAXIMUM(*maxfdp, channel_max_fd);
1.84 markus 2177:
1.243 djm 2178: nfdset = howmany(n+1, NFDBITS);
2179: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2180: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2181: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2182: sz = nfdset * sizeof(fd_mask);
2183:
1.132 markus 2184: /* perhaps check sz < nalloc/2 and shrink? */
2185: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2186: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2187: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2188: *nallocp = sz;
1.84 markus 2189: }
1.132 markus 2190: *maxfdp = n;
1.84 markus 2191: memset(*readsetp, 0, sz);
2192: memset(*writesetp, 0, sz);
2193:
1.100 markus 2194: if (!rekeying)
1.317 djm 2195: channel_handler(channel_pre, *readsetp, *writesetp,
2196: minwait_secs);
1.41 markus 2197: }
2198:
1.121 markus 2199: /*
2200: * After select, perform any appropriate operations for channels which have
2201: * events pending.
2202: */
1.49 markus 2203: void
1.237 deraadt 2204: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 2205: {
1.317 djm 2206: channel_handler(channel_post, readset, writeset, NULL);
1.41 markus 2207: }
2208:
1.121 markus 2209:
1.84 markus 2210: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2211: void
1.142 itojun 2212: channel_output_poll(void)
1.1 deraadt 2213: {
1.41 markus 2214: Channel *c;
1.209 avsm 2215: u_int i, len;
1.1 deraadt 2216:
1.25 markus 2217: for (i = 0; i < channels_alloc; i++) {
1.113 markus 2218: c = channels[i];
2219: if (c == NULL)
2220: continue;
1.37 markus 2221:
1.121 markus 2222: /*
2223: * We are only interested in channels that can have buffered
2224: * incoming data.
2225: */
1.37 markus 2226: if (compat13) {
1.41 markus 2227: if (c->type != SSH_CHANNEL_OPEN &&
2228: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 2229: continue;
2230: } else {
1.41 markus 2231: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 2232: continue;
2233: }
1.46 markus 2234: if (compat20 &&
2235: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2236: /* XXX is this true? */
1.140 markus 2237: debug3("channel %d: will not send data after close", c->self);
1.44 markus 2238: continue;
2239: }
1.25 markus 2240:
2241: /* Get the amount of buffered data for this channel. */
1.93 markus 2242: if ((c->istate == CHAN_INPUT_OPEN ||
2243: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2244: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 2245: if (c->datagram) {
2246: if (len > 0) {
2247: u_char *data;
2248: u_int dlen;
2249:
2250: data = buffer_get_string(&c->input,
2251: &dlen);
1.309 djm 2252: if (dlen > c->remote_window ||
2253: dlen > c->remote_maxpacket) {
2254: debug("channel %d: datagram "
2255: "too big for channel",
2256: c->self);
1.321 djm 2257: free(data);
1.309 djm 2258: continue;
2259: }
1.228 reyk 2260: packet_start(SSH2_MSG_CHANNEL_DATA);
2261: packet_put_int(c->remote_id);
2262: packet_put_string(data, dlen);
2263: packet_send();
1.345 djm 2264: c->remote_window -= dlen;
1.321 djm 2265: free(data);
1.228 reyk 2266: }
2267: continue;
2268: }
1.121 markus 2269: /*
2270: * Send some data for the other side over the secure
2271: * connection.
2272: */
1.44 markus 2273: if (compat20) {
2274: if (len > c->remote_window)
2275: len = c->remote_window;
2276: if (len > c->remote_maxpacket)
2277: len = c->remote_maxpacket;
1.25 markus 2278: } else {
1.44 markus 2279: if (packet_is_interactive()) {
2280: if (len > 1024)
2281: len = 512;
2282: } else {
2283: /* Keep the packets at reasonable size. */
2284: if (len > packet_get_maxsize()/2)
2285: len = packet_get_maxsize()/2;
2286: }
1.25 markus 2287: }
1.41 markus 2288: if (len > 0) {
1.44 markus 2289: packet_start(compat20 ?
2290: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2291: packet_put_int(c->remote_id);
2292: packet_put_string(buffer_ptr(&c->input), len);
2293: packet_send();
2294: buffer_consume(&c->input, len);
2295: c->remote_window -= len;
2296: }
2297: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2298: if (compat13)
2299: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2300: /*
2301: * input-buffer is empty and read-socket shutdown:
1.172 markus 2302: * tell peer, that we will not send more data: send IEOF.
2303: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2304: */
1.172 markus 2305: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2306: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2307: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2308: else
2309: chan_ibuf_empty(c);
1.25 markus 2310: }
1.44 markus 2311: /* Send extended data, i.e. stderr */
2312: if (compat20 &&
1.172 markus 2313: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2314: c->remote_window > 0 &&
2315: (len = buffer_len(&c->extended)) > 0 &&
2316: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2317: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2318: c->self, c->remote_window, buffer_len(&c->extended),
2319: c->extended_usage);
1.44 markus 2320: if (len > c->remote_window)
2321: len = c->remote_window;
2322: if (len > c->remote_maxpacket)
2323: len = c->remote_maxpacket;
2324: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2325: packet_put_int(c->remote_id);
2326: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2327: packet_put_string(buffer_ptr(&c->extended), len);
2328: packet_send();
2329: buffer_consume(&c->extended, len);
2330: c->remote_window -= len;
1.93 markus 2331: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2332: }
1.25 markus 2333: }
1.1 deraadt 2334: }
2335:
1.121 markus 2336:
2337: /* -- protocol input */
1.249 djm 2338:
2339: /* ARGSUSED */
1.339 markus 2340: int
1.154 markus 2341: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2342: {
1.37 markus 2343: int id;
1.332 djm 2344: const u_char *data;
1.309 djm 2345: u_int data_len, win_len;
1.41 markus 2346: Channel *c;
1.25 markus 2347:
2348: /* Get the channel number and verify it. */
1.37 markus 2349: id = packet_get_int();
1.41 markus 2350: c = channel_lookup(id);
2351: if (c == NULL)
1.37 markus 2352: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2353:
2354: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2355: if (c->type != SSH_CHANNEL_OPEN &&
2356: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2357: return 0;
1.37 markus 2358:
1.25 markus 2359: /* Get the data. */
1.274 markus 2360: data = packet_get_string_ptr(&data_len);
1.309 djm 2361: win_len = data_len;
2362: if (c->datagram)
2363: win_len += 4; /* string length header */
1.200 markus 2364:
2365: /*
2366: * Ignore data for protocol > 1.3 if output end is no longer open.
2367: * For protocol 2 the sending side is reducing its window as it sends
2368: * data, so we must 'fake' consumption of the data in order to ensure
2369: * that window updates are sent back. Otherwise the connection might
2370: * deadlock.
2371: */
2372: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2373: if (compat20) {
1.309 djm 2374: c->local_window -= win_len;
2375: c->local_consumed += win_len;
1.200 markus 2376: }
1.339 markus 2377: return 0;
1.200 markus 2378: }
1.41 markus 2379:
1.143 deraadt 2380: if (compat20) {
1.309 djm 2381: if (win_len > c->local_maxpacket) {
1.188 itojun 2382: logit("channel %d: rcvd big packet %d, maxpack %d",
1.309 djm 2383: c->self, win_len, c->local_maxpacket);
1.44 markus 2384: }
1.309 djm 2385: if (win_len > c->local_window) {
1.188 itojun 2386: logit("channel %d: rcvd too much data %d, win %d",
1.309 djm 2387: c->self, win_len, c->local_window);
1.339 markus 2388: return 0;
1.44 markus 2389: }
1.309 djm 2390: c->local_window -= win_len;
1.44 markus 2391: }
1.228 reyk 2392: if (c->datagram)
2393: buffer_put_string(&c->output, data, data_len);
2394: else
2395: buffer_append(&c->output, data, data_len);
1.274 markus 2396: packet_check_eom();
1.339 markus 2397: return 0;
1.1 deraadt 2398: }
1.121 markus 2399:
1.249 djm 2400: /* ARGSUSED */
1.339 markus 2401: int
1.154 markus 2402: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2403: {
2404: int id;
2405: char *data;
1.177 markus 2406: u_int data_len, tcode;
1.44 markus 2407: Channel *c;
2408:
2409: /* Get the channel number and verify it. */
2410: id = packet_get_int();
2411: c = channel_lookup(id);
2412:
2413: if (c == NULL)
2414: packet_disconnect("Received extended_data for bad channel %d.", id);
2415: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2416: logit("channel %d: ext data for non open", id);
1.339 markus 2417: return 0;
1.172 markus 2418: }
2419: if (c->flags & CHAN_EOF_RCVD) {
2420: if (datafellows & SSH_BUG_EXTEOF)
2421: debug("channel %d: accepting ext data after eof", id);
2422: else
2423: packet_disconnect("Received extended_data after EOF "
2424: "on channel %d.", id);
1.44 markus 2425: }
2426: tcode = packet_get_int();
2427: if (c->efd == -1 ||
2428: c->extended_usage != CHAN_EXTENDED_WRITE ||
2429: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2430: logit("channel %d: bad ext data", c->self);
1.339 markus 2431: return 0;
1.44 markus 2432: }
2433: data = packet_get_string(&data_len);
1.152 markus 2434: packet_check_eom();
1.44 markus 2435: if (data_len > c->local_window) {
1.188 itojun 2436: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2437: c->self, data_len, c->local_window);
1.321 djm 2438: free(data);
1.339 markus 2439: return 0;
1.44 markus 2440: }
1.70 markus 2441: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2442: c->local_window -= data_len;
2443: buffer_append(&c->extended, data, data_len);
1.321 djm 2444: free(data);
1.339 markus 2445: return 0;
1.44 markus 2446: }
2447:
1.249 djm 2448: /* ARGSUSED */
1.339 markus 2449: int
1.154 markus 2450: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2451: {
2452: int id;
2453: Channel *c;
2454:
2455: id = packet_get_int();
1.152 markus 2456: packet_check_eom();
1.41 markus 2457: c = channel_lookup(id);
2458: if (c == NULL)
2459: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2460: chan_rcvd_ieof(c);
1.133 markus 2461:
2462: /* XXX force input close */
1.156 markus 2463: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2464: debug("channel %d: FORCE input drain", c->self);
2465: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2466: if (buffer_len(&c->input) == 0)
2467: chan_ibuf_empty(c);
1.133 markus 2468: }
1.339 markus 2469: return 0;
1.41 markus 2470: }
1.1 deraadt 2471:
1.249 djm 2472: /* ARGSUSED */
1.339 markus 2473: int
1.154 markus 2474: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2475: {
1.41 markus 2476: int id;
2477: Channel *c;
1.1 deraadt 2478:
1.41 markus 2479: id = packet_get_int();
1.152 markus 2480: packet_check_eom();
1.41 markus 2481: c = channel_lookup(id);
2482: if (c == NULL)
2483: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2484:
2485: /*
2486: * Send a confirmation that we have closed the channel and no more
2487: * data is coming for it.
2488: */
1.25 markus 2489: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2490: packet_put_int(c->remote_id);
1.25 markus 2491: packet_send();
2492:
1.27 markus 2493: /*
2494: * If the channel is in closed state, we have sent a close request,
2495: * and the other side will eventually respond with a confirmation.
2496: * Thus, we cannot free the channel here, because then there would be
2497: * no-one to receive the confirmation. The channel gets freed when
2498: * the confirmation arrives.
2499: */
1.41 markus 2500: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2501: /*
2502: * Not a closed channel - mark it as draining, which will
2503: * cause it to be freed later.
2504: */
1.158 markus 2505: buffer_clear(&c->input);
1.41 markus 2506: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2507: }
1.339 markus 2508: return 0;
1.1 deraadt 2509: }
2510:
1.41 markus 2511: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2512: /* ARGSUSED */
1.339 markus 2513: int
1.154 markus 2514: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2515: {
2516: int id = packet_get_int();
2517: Channel *c = channel_lookup(id);
1.151 markus 2518:
1.152 markus 2519: packet_check_eom();
1.41 markus 2520: if (c == NULL)
2521: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2522: chan_rcvd_oclose(c);
1.339 markus 2523: return 0;
1.41 markus 2524: }
1.1 deraadt 2525:
1.249 djm 2526: /* ARGSUSED */
1.339 markus 2527: int
1.154 markus 2528: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2529: {
1.41 markus 2530: int id = packet_get_int();
2531: Channel *c = channel_lookup(id);
1.1 deraadt 2532:
1.152 markus 2533: packet_check_eom();
1.41 markus 2534: if (c == NULL)
2535: packet_disconnect("Received close confirmation for "
2536: "out-of-range channel %d.", id);
1.323 dtucker 2537: if (c->type != SSH_CHANNEL_CLOSED && c->type != SSH_CHANNEL_ABANDONED)
1.41 markus 2538: packet_disconnect("Received close confirmation for "
2539: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2540: channel_free(c);
1.339 markus 2541: return 0;
1.1 deraadt 2542: }
2543:
1.249 djm 2544: /* ARGSUSED */
1.339 markus 2545: int
1.154 markus 2546: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2547: {
1.41 markus 2548: int id, remote_id;
2549: Channel *c;
1.1 deraadt 2550:
1.41 markus 2551: id = packet_get_int();
2552: c = channel_lookup(id);
1.25 markus 2553:
1.41 markus 2554: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2555: packet_disconnect("Received open confirmation for "
2556: "non-opening channel %d.", id);
2557: remote_id = packet_get_int();
1.27 markus 2558: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2559: c->remote_id = remote_id;
2560: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2561:
2562: if (compat20) {
2563: c->remote_window = packet_get_int();
2564: c->remote_maxpacket = packet_get_int();
1.275 djm 2565: if (c->open_confirm) {
1.70 markus 2566: debug2("callback start");
1.304 djm 2567: c->open_confirm(c->self, 1, c->open_confirm_ctx);
1.70 markus 2568: debug2("callback done");
1.44 markus 2569: }
1.194 markus 2570: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2571: c->remote_window, c->remote_maxpacket);
2572: }
1.152 markus 2573: packet_check_eom();
1.339 markus 2574: return 0;
1.1 deraadt 2575: }
2576:
1.127 itojun 2577: static char *
1.114 markus 2578: reason2txt(int reason)
2579: {
1.143 deraadt 2580: switch (reason) {
1.114 markus 2581: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2582: return "administratively prohibited";
2583: case SSH2_OPEN_CONNECT_FAILED:
2584: return "connect failed";
2585: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2586: return "unknown channel type";
2587: case SSH2_OPEN_RESOURCE_SHORTAGE:
2588: return "resource shortage";
2589: }
1.117 stevesk 2590: return "unknown reason";
1.114 markus 2591: }
2592:
1.249 djm 2593: /* ARGSUSED */
1.339 markus 2594: int
1.154 markus 2595: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2596: {
1.86 markus 2597: int id, reason;
2598: char *msg = NULL, *lang = NULL;
1.41 markus 2599: Channel *c;
2600:
2601: id = packet_get_int();
2602: c = channel_lookup(id);
1.25 markus 2603:
1.41 markus 2604: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2605: packet_disconnect("Received open failure for "
2606: "non-opening channel %d.", id);
1.44 markus 2607: if (compat20) {
1.86 markus 2608: reason = packet_get_int();
1.110 markus 2609: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2610: msg = packet_get_string(NULL);
2611: lang = packet_get_string(NULL);
2612: }
1.188 itojun 2613: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2614: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.321 djm 2615: free(msg);
2616: free(lang);
1.304 djm 2617: if (c->open_confirm) {
2618: debug2("callback start");
2619: c->open_confirm(c->self, 0, c->open_confirm_ctx);
2620: debug2("callback done");
2621: }
1.44 markus 2622: }
1.152 markus 2623: packet_check_eom();
1.291 djm 2624: /* Schedule the channel for cleanup/deletion. */
2625: chan_mark_dead(c);
1.339 markus 2626: return 0;
1.44 markus 2627: }
2628:
1.249 djm 2629: /* ARGSUSED */
1.339 markus 2630: int
1.154 markus 2631: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2632: {
2633: Channel *c;
1.178 markus 2634: int id;
1.346 djm 2635: u_int adjust, tmp;
1.121 markus 2636:
2637: if (!compat20)
1.339 markus 2638: return 0;
1.121 markus 2639:
2640: /* Get the channel number and verify it. */
2641: id = packet_get_int();
2642: c = channel_lookup(id);
1.1 deraadt 2643:
1.229 markus 2644: if (c == NULL) {
2645: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 2646: return 0;
1.121 markus 2647: }
2648: adjust = packet_get_int();
1.152 markus 2649: packet_check_eom();
1.178 markus 2650: debug2("channel %d: rcvd adjust %u", id, adjust);
1.346 djm 2651: if ((tmp = c->remote_window + adjust) < c->remote_window)
2652: fatal("channel %d: adjust %u overflows remote window %u",
2653: id, adjust, c->remote_window);
2654: c->remote_window = tmp;
1.339 markus 2655: return 0;
1.121 markus 2656: }
1.1 deraadt 2657:
1.249 djm 2658: /* ARGSUSED */
1.339 markus 2659: int
1.154 markus 2660: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2661: {
1.121 markus 2662: Channel *c = NULL;
2663: u_short host_port;
2664: char *host, *originator_string;
1.276 djm 2665: int remote_id;
1.121 markus 2666:
2667: remote_id = packet_get_int();
2668: host = packet_get_string(NULL);
2669: host_port = packet_get_int();
1.25 markus 2670:
1.121 markus 2671: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2672: originator_string = packet_get_string(NULL);
2673: } else {
2674: originator_string = xstrdup("unknown (remote did not supply name)");
2675: }
1.152 markus 2676: packet_check_eom();
1.336 millert 2677: c = channel_connect_to_port(host, host_port,
1.276 djm 2678: "connected socket", originator_string);
1.321 djm 2679: free(originator_string);
2680: free(host);
1.121 markus 2681: if (c == NULL) {
2682: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2683: packet_put_int(remote_id);
2684: packet_send();
1.276 djm 2685: } else
2686: c->remote_id = remote_id;
1.339 markus 2687: return 0;
1.1 deraadt 2688: }
2689:
1.275 djm 2690: /* ARGSUSED */
1.339 markus 2691: int
1.275 djm 2692: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2693: {
2694: Channel *c;
2695: struct channel_confirm *cc;
1.289 markus 2696: int id;
1.275 djm 2697:
2698: /* Reset keepalive timeout */
1.296 andreas 2699: packet_set_alive_timeouts(0);
1.275 djm 2700:
1.289 markus 2701: id = packet_get_int();
1.275 djm 2702: packet_check_eom();
2703:
1.289 markus 2704: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2705:
1.289 markus 2706: if ((c = channel_lookup(id)) == NULL) {
2707: logit("channel_input_status_confirm: %d: unknown", id);
1.339 markus 2708: return 0;
1.275 djm 2709: }
2710: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 2711: return 0;
1.275 djm 2712: cc->cb(type, c, cc->ctx);
2713: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 2714: explicit_bzero(cc, sizeof(*cc));
1.321 djm 2715: free(cc);
1.339 markus 2716: return 0;
1.275 djm 2717: }
1.121 markus 2718:
2719: /* -- tcp forwarding */
1.135 markus 2720:
2721: void
2722: channel_set_af(int af)
2723: {
2724: IPv4or6 = af;
2725: }
1.121 markus 2726:
1.312 djm 2727:
2728: /*
2729: * Determine whether or not a port forward listens to loopback, the
2730: * specified address or wildcard. On the client, a specified bind
2731: * address will always override gateway_ports. On the server, a
2732: * gateway_ports of 1 (``yes'') will override the client's specification
2733: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
2734: * will bind to whatever address the client asked for.
2735: *
2736: * Special-case listen_addrs are:
2737: *
2738: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2739: * "" (empty string), "*" -> wildcard v4/v6
2740: * "localhost" -> loopback v4/v6
1.334 djm 2741: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 2742: */
2743: static const char *
2744: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 2745: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 2746: {
2747: const char *addr = NULL;
2748: int wildcard = 0;
2749:
2750: if (listen_addr == NULL) {
2751: /* No address specified: default to gateway_ports setting */
1.336 millert 2752: if (fwd_opts->gateway_ports)
1.312 djm 2753: wildcard = 1;
1.336 millert 2754: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 2755: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2756: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
2757: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 2758: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 2759: wildcard = 1;
1.326 djm 2760: /*
2761: * Notify client if they requested a specific listen
2762: * address and it was overridden.
2763: */
2764: if (*listen_addr != '\0' &&
2765: strcmp(listen_addr, "0.0.0.0") != 0 &&
2766: strcmp(listen_addr, "*") != 0) {
2767: packet_send_debug("Forwarding listen address "
2768: "\"%s\" overridden by server "
2769: "GatewayPorts", listen_addr);
2770: }
1.334 djm 2771: } else if (strcmp(listen_addr, "localhost") != 0 ||
2772: strcmp(listen_addr, "127.0.0.1") == 0 ||
2773: strcmp(listen_addr, "::1") == 0) {
2774: /* Accept localhost address when GatewayPorts=yes */
2775: addr = listen_addr;
1.326 djm 2776: }
1.334 djm 2777: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
2778: strcmp(listen_addr, "::1") == 0) {
2779: /*
2780: * If a specific IPv4/IPv6 localhost address has been
2781: * requested then accept it even if gateway_ports is in
2782: * effect. This allows the client to prefer IPv4 or IPv6.
2783: */
2784: addr = listen_addr;
1.312 djm 2785: }
2786: if (wildcardp != NULL)
2787: *wildcardp = wildcard;
2788: return addr;
2789: }
2790:
1.160 markus 2791: static int
1.336 millert 2792: channel_setup_fwd_listener_tcpip(int type, struct Forward *fwd,
2793: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.25 markus 2794: {
1.113 markus 2795: Channel *c;
1.226 djm 2796: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2797: struct addrinfo hints, *ai, *aitop;
1.212 djm 2798: const char *host, *addr;
1.35 markus 2799: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2800: in_port_t *lport_p;
1.25 markus 2801:
1.212 djm 2802: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2803:
1.344 millert 2804: if (is_client && fwd->connect_path != NULL) {
2805: host = fwd->connect_path;
2806: } else {
2807: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2808: fwd->listen_host : fwd->connect_host;
2809: if (host == NULL) {
2810: error("No forward host name.");
2811: return 0;
2812: }
2813: if (strlen(host) >= NI_MAXHOST) {
2814: error("Forward host name too long.");
2815: return 0;
2816: }
1.87 markus 2817: }
1.25 markus 2818:
1.312 djm 2819: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 2820: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
2821: is_client, fwd_opts);
2822: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 2823: type, wildcard, (addr == NULL) ? "NULL" : addr);
2824:
2825: /*
1.35 markus 2826: * getaddrinfo returns a loopback address if the hostname is
2827: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2828: */
1.35 markus 2829: memset(&hints, 0, sizeof(hints));
2830: hints.ai_family = IPv4or6;
1.212 djm 2831: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2832: hints.ai_socktype = SOCK_STREAM;
1.336 millert 2833: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 2834: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2835: if (addr == NULL) {
2836: /* This really shouldn't happen */
2837: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2838: ssh_gai_strerror(r));
1.212 djm 2839: } else {
1.336 millert 2840: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 2841: ssh_gai_strerror(r));
1.212 djm 2842: }
1.218 markus 2843: return 0;
1.212 djm 2844: }
1.295 djm 2845: if (allocated_listen_port != NULL)
2846: *allocated_listen_port = 0;
1.35 markus 2847: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2848: switch (ai->ai_family) {
2849: case AF_INET:
2850: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2851: sin_port;
2852: break;
2853: case AF_INET6:
2854: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2855: sin6_port;
2856: break;
2857: default:
1.35 markus 2858: continue;
1.295 djm 2859: }
2860: /*
2861: * If allocating a port for -R forwards, then use the
2862: * same port for all address families.
2863: */
1.336 millert 2864: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2865: allocated_listen_port != NULL && *allocated_listen_port > 0)
2866: *lport_p = htons(*allocated_listen_port);
2867:
1.35 markus 2868: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2869: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 2870: error("%s: getnameinfo failed", __func__);
1.35 markus 2871: continue;
2872: }
2873: /* Create a port to listen for the host. */
1.300 dtucker 2874: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2875: if (sock < 0) {
2876: /* this is no error since kernel may not support ipv6 */
2877: verbose("socket: %.100s", strerror(errno));
2878: continue;
2879: }
1.226 djm 2880:
2881: channel_set_reuseaddr(sock);
1.182 stevesk 2882:
1.295 djm 2883: debug("Local forwarding listening on %s port %s.",
2884: ntop, strport);
1.35 markus 2885:
2886: /* Bind the socket to the address. */
2887: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2888: /* address can be in use ipv6 address is already bound */
2889: verbose("bind: %.100s", strerror(errno));
2890: close(sock);
2891: continue;
2892: }
2893: /* Start listening for connections on the socket. */
1.199 markus 2894: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2895: error("listen: %.100s", strerror(errno));
2896: close(sock);
2897: continue;
2898: }
1.295 djm 2899:
2900: /*
1.336 millert 2901: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 2902: * record what we got.
2903: */
1.336 millert 2904: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2905: allocated_listen_port != NULL &&
2906: *allocated_listen_port == 0) {
1.350 djm 2907: *allocated_listen_port = get_local_port(sock);
1.295 djm 2908: debug("Allocated listen port %d",
2909: *allocated_listen_port);
2910: }
2911:
1.35 markus 2912: /* Allocate a channel number for the socket. */
1.121 markus 2913: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2914: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2915: 0, "port listener", 1);
1.293 djm 2916: c->path = xstrdup(host);
1.336 millert 2917: c->host_port = fwd->connect_port;
1.312 djm 2918: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 2919: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 2920: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
2921: c->listening_port = *allocated_listen_port;
2922: else
1.336 millert 2923: c->listening_port = fwd->listen_port;
1.35 markus 2924: success = 1;
2925: }
2926: if (success == 0)
1.336 millert 2927: error("%s: cannot listen to port: %d", __func__,
2928: fwd->listen_port);
1.35 markus 2929: freeaddrinfo(aitop);
1.87 markus 2930: return success;
1.25 markus 2931: }
1.1 deraadt 2932:
1.336 millert 2933: static int
2934: channel_setup_fwd_listener_streamlocal(int type, struct Forward *fwd,
2935: struct ForwardOptions *fwd_opts)
2936: {
2937: struct sockaddr_un sunaddr;
2938: const char *path;
2939: Channel *c;
2940: int port, sock;
2941: mode_t omask;
2942:
2943: switch (type) {
2944: case SSH_CHANNEL_UNIX_LISTENER:
2945: if (fwd->connect_path != NULL) {
2946: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
2947: error("Local connecting path too long: %s",
2948: fwd->connect_path);
2949: return 0;
2950: }
2951: path = fwd->connect_path;
2952: port = PORT_STREAMLOCAL;
2953: } else {
2954: if (fwd->connect_host == NULL) {
2955: error("No forward host name.");
2956: return 0;
2957: }
2958: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
2959: error("Forward host name too long.");
2960: return 0;
2961: }
2962: path = fwd->connect_host;
2963: port = fwd->connect_port;
2964: }
2965: break;
2966: case SSH_CHANNEL_RUNIX_LISTENER:
2967: path = fwd->listen_path;
2968: port = PORT_STREAMLOCAL;
2969: break;
2970: default:
2971: error("%s: unexpected channel type %d", __func__, type);
2972: return 0;
2973: }
2974:
2975: if (fwd->listen_path == NULL) {
2976: error("No forward path name.");
2977: return 0;
2978: }
2979: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
2980: error("Local listening path too long: %s", fwd->listen_path);
2981: return 0;
2982: }
2983:
2984: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
2985:
2986: /* Start a Unix domain listener. */
2987: omask = umask(fwd_opts->streamlocal_bind_mask);
2988: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
2989: fwd_opts->streamlocal_bind_unlink);
2990: umask(omask);
2991: if (sock < 0)
2992: return 0;
2993:
2994: debug("Local forwarding listening on path %s.", fwd->listen_path);
2995:
2996: /* Allocate a channel number for the socket. */
2997: c = channel_new("unix listener", type, sock, sock, -1,
2998: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
2999: 0, "unix listener", 1);
3000: c->path = xstrdup(path);
3001: c->host_port = port;
3002: c->listening_port = PORT_STREAMLOCAL;
3003: c->listening_addr = xstrdup(fwd->listen_path);
3004: return 1;
3005: }
3006:
3007: static int
3008: channel_cancel_rport_listener_tcpip(const char *host, u_short port)
1.202 djm 3009: {
1.209 avsm 3010: u_int i;
3011: int found = 0;
1.202 djm 3012:
1.213 deraadt 3013: for (i = 0; i < channels_alloc; i++) {
1.202 djm 3014: Channel *c = channels[i];
1.312 djm 3015: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3016: continue;
3017: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3018: debug2("%s: close channel %d", __func__, i);
3019: channel_free(c);
3020: found = 1;
3021: }
3022: }
3023:
3024: return (found);
3025: }
3026:
1.336 millert 3027: static int
3028: channel_cancel_rport_listener_streamlocal(const char *path)
3029: {
3030: u_int i;
3031: int found = 0;
3032:
3033: for (i = 0; i < channels_alloc; i++) {
3034: Channel *c = channels[i];
3035: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3036: continue;
3037: if (c->path == NULL)
3038: continue;
3039: if (strcmp(c->path, path) == 0) {
3040: debug2("%s: close channel %d", __func__, i);
3041: channel_free(c);
3042: found = 1;
3043: }
3044: }
3045:
3046: return (found);
3047: }
3048:
1.312 djm 3049: int
1.336 millert 3050: channel_cancel_rport_listener(struct Forward *fwd)
3051: {
3052: if (fwd->listen_path != NULL)
3053: return channel_cancel_rport_listener_streamlocal(fwd->listen_path);
3054: else
3055: return channel_cancel_rport_listener_tcpip(fwd->listen_host, fwd->listen_port);
3056: }
3057:
3058: static int
3059: channel_cancel_lport_listener_tcpip(const char *lhost, u_short lport,
3060: int cport, struct ForwardOptions *fwd_opts)
1.312 djm 3061: {
3062: u_int i;
3063: int found = 0;
1.336 millert 3064: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3065:
1.312 djm 3066: for (i = 0; i < channels_alloc; i++) {
3067: Channel *c = channels[i];
3068: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3069: continue;
1.313 markus 3070: if (c->listening_port != lport)
1.312 djm 3071: continue;
1.313 markus 3072: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3073: /* skip dynamic forwardings */
3074: if (c->host_port == 0)
3075: continue;
3076: } else {
3077: if (c->host_port != cport)
3078: continue;
3079: }
1.312 djm 3080: if ((c->listening_addr == NULL && addr != NULL) ||
3081: (c->listening_addr != NULL && addr == NULL))
3082: continue;
3083: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3084: debug2("%s: close channel %d", __func__, i);
1.202 djm 3085: channel_free(c);
3086: found = 1;
3087: }
3088: }
3089:
3090: return (found);
3091: }
3092:
1.336 millert 3093: static int
3094: channel_cancel_lport_listener_streamlocal(const char *path)
3095: {
3096: u_int i;
3097: int found = 0;
3098:
3099: if (path == NULL) {
3100: error("%s: no path specified.", __func__);
3101: return 0;
3102: }
3103:
3104: for (i = 0; i < channels_alloc; i++) {
3105: Channel *c = channels[i];
3106: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3107: continue;
3108: if (c->listening_addr == NULL)
3109: continue;
3110: if (strcmp(c->listening_addr, path) == 0) {
3111: debug2("%s: close channel %d", __func__, i);
3112: channel_free(c);
3113: found = 1;
3114: }
3115: }
3116:
3117: return (found);
3118: }
3119:
3120: int
3121: channel_cancel_lport_listener(struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
3122: {
3123: if (fwd->listen_path != NULL)
3124: return channel_cancel_lport_listener_streamlocal(fwd->listen_path);
3125: else
3126: return channel_cancel_lport_listener_tcpip(fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3127: }
3128:
1.160 markus 3129: /* protocol local port fwd, used by ssh (and sshd in v1) */
3130: int
1.336 millert 3131: channel_setup_local_fwd_listener(struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3132: {
1.336 millert 3133: if (fwd->listen_path != NULL) {
3134: return channel_setup_fwd_listener_streamlocal(
3135: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3136: } else {
3137: return channel_setup_fwd_listener_tcpip(SSH_CHANNEL_PORT_LISTENER,
3138: fwd, NULL, fwd_opts);
3139: }
1.160 markus 3140: }
3141:
3142: /* protocol v2 remote port fwd, used by sshd */
3143: int
1.336 millert 3144: channel_setup_remote_fwd_listener(struct Forward *fwd,
3145: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3146: {
1.336 millert 3147: if (fwd->listen_path != NULL) {
3148: return channel_setup_fwd_listener_streamlocal(
3149: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3150: } else {
3151: return channel_setup_fwd_listener_tcpip(
3152: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3153: fwd_opts);
3154: }
1.160 markus 3155: }
3156:
1.27 markus 3157: /*
1.312 djm 3158: * Translate the requested rfwd listen host to something usable for
3159: * this server.
3160: */
3161: static const char *
3162: channel_rfwd_bind_host(const char *listen_host)
3163: {
3164: if (listen_host == NULL) {
3165: if (datafellows & SSH_BUG_RFWD_ADDR)
3166: return "127.0.0.1";
3167: else
3168: return "localhost";
3169: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3170: if (datafellows & SSH_BUG_RFWD_ADDR)
3171: return "0.0.0.0";
3172: else
3173: return "";
3174: } else
3175: return listen_host;
3176: }
3177:
3178: /*
1.27 markus 3179: * Initiate forwarding of connections to port "port" on remote host through
3180: * the secure channel to host:port from local side.
1.315 markus 3181: * Returns handle (index) for updating the dynamic listen port with
3182: * channel_update_permitted_opens().
1.27 markus 3183: */
1.253 markus 3184: int
1.336 millert 3185: channel_request_remote_forwarding(struct Forward *fwd)
1.25 markus 3186: {
1.315 markus 3187: int type, success = 0, idx = -1;
1.73 markus 3188:
1.25 markus 3189: /* Send the forward request to the remote side. */
1.44 markus 3190: if (compat20) {
3191: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1.336 millert 3192: if (fwd->listen_path != NULL) {
3193: packet_put_cstring("streamlocal-forward@openssh.com");
3194: packet_put_char(1); /* boolean: want reply */
3195: packet_put_cstring(fwd->listen_path);
3196: } else {
3197: packet_put_cstring("tcpip-forward");
3198: packet_put_char(1); /* boolean: want reply */
3199: packet_put_cstring(channel_rfwd_bind_host(fwd->listen_host));
3200: packet_put_int(fwd->listen_port);
3201: }
1.73 markus 3202: packet_send();
3203: packet_write_wait();
3204: /* Assume that server accepts the request */
3205: success = 1;
1.336 millert 3206: } else if (fwd->listen_path == NULL) {
1.44 markus 3207: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.336 millert 3208: packet_put_int(fwd->listen_port);
3209: packet_put_cstring(fwd->connect_host);
3210: packet_put_int(fwd->connect_port);
1.44 markus 3211: packet_send();
3212: packet_write_wait();
1.73 markus 3213:
3214: /* Wait for response from the remote side. */
1.153 markus 3215: type = packet_read();
1.73 markus 3216: switch (type) {
3217: case SSH_SMSG_SUCCESS:
3218: success = 1;
3219: break;
3220: case SSH_SMSG_FAILURE:
3221: break;
3222: default:
3223: /* Unknown packet */
3224: packet_disconnect("Protocol error for port forward request:"
3225: "received packet type %d.", type);
3226: }
1.336 millert 3227: } else {
3228: logit("Warning: Server does not support remote stream local forwarding.");
1.73 markus 3229: }
3230: if (success) {
1.305 djm 3231: /* Record that connection to this host/port is permitted. */
1.342 deraadt 3232: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3233: num_permitted_opens + 1, sizeof(*permitted_opens));
1.315 markus 3234: idx = num_permitted_opens++;
1.336 millert 3235: if (fwd->connect_path != NULL) {
3236: permitted_opens[idx].host_to_connect =
3237: xstrdup(fwd->connect_path);
3238: permitted_opens[idx].port_to_connect =
3239: PORT_STREAMLOCAL;
3240: } else {
3241: permitted_opens[idx].host_to_connect =
3242: xstrdup(fwd->connect_host);
3243: permitted_opens[idx].port_to_connect =
3244: fwd->connect_port;
3245: }
3246: if (fwd->listen_path != NULL) {
3247: permitted_opens[idx].listen_host = NULL;
3248: permitted_opens[idx].listen_path =
3249: xstrdup(fwd->listen_path);
3250: permitted_opens[idx].listen_port = PORT_STREAMLOCAL;
3251: } else {
3252: permitted_opens[idx].listen_host =
3253: fwd->listen_host ? xstrdup(fwd->listen_host) : NULL;
3254: permitted_opens[idx].listen_path = NULL;
3255: permitted_opens[idx].listen_port = fwd->listen_port;
3256: }
1.44 markus 3257: }
1.315 markus 3258: return (idx);
1.1 deraadt 3259: }
3260:
1.333 markus 3261: static int
3262: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3263: int requestedport)
1.333 markus 3264: {
3265: if (allowed_open->host_to_connect == NULL)
3266: return 0;
3267: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3268: allowed_open->port_to_connect != requestedport)
3269: return 0;
1.351 dtucker 3270: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3271: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3272: return 0;
3273: return 1;
3274: }
3275:
3276: /*
1.336 millert 3277: * Note that in the listen host/port case
1.333 markus 3278: * we don't support FWD_PERMIT_ANY_PORT and
3279: * need to translate between the configured-host (listen_host)
3280: * and what we've sent to the remote server (channel_rfwd_bind_host)
3281: */
3282: static int
1.336 millert 3283: open_listen_match_tcpip(ForwardPermission *allowed_open,
3284: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3285: {
3286: const char *allowed_host;
3287:
3288: if (allowed_open->host_to_connect == NULL)
3289: return 0;
3290: if (allowed_open->listen_port != requestedport)
3291: return 0;
1.335 djm 3292: if (!translate && allowed_open->listen_host == NULL &&
3293: requestedhost == NULL)
3294: return 1;
1.333 markus 3295: allowed_host = translate ?
3296: channel_rfwd_bind_host(allowed_open->listen_host) :
3297: allowed_open->listen_host;
3298: if (allowed_host == NULL ||
3299: strcmp(allowed_host, requestedhost) != 0)
3300: return 0;
3301: return 1;
3302: }
3303:
1.336 millert 3304: static int
3305: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3306: const char *requestedpath)
3307: {
3308: if (allowed_open->host_to_connect == NULL)
3309: return 0;
3310: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3311: return 0;
3312: if (allowed_open->listen_path == NULL ||
3313: strcmp(allowed_open->listen_path, requestedpath) != 0)
3314: return 0;
3315: return 1;
3316: }
3317:
1.27 markus 3318: /*
1.208 deraadt 3319: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3320: * local side.
3321: */
1.336 millert 3322: static int
3323: channel_request_rforward_cancel_tcpip(const char *host, u_short port)
1.202 djm 3324: {
3325: int i;
3326:
3327: if (!compat20)
1.312 djm 3328: return -1;
1.202 djm 3329:
3330: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3331: if (open_listen_match_tcpip(&permitted_opens[i], host, port, 0))
1.202 djm 3332: break;
3333: }
3334: if (i >= num_permitted_opens) {
3335: debug("%s: requested forward not found", __func__);
1.312 djm 3336: return -1;
1.202 djm 3337: }
3338: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3339: packet_put_cstring("cancel-tcpip-forward");
3340: packet_put_char(0);
1.312 djm 3341: packet_put_cstring(channel_rfwd_bind_host(host));
1.202 djm 3342: packet_put_int(port);
3343: packet_send();
3344:
1.336 millert 3345: permitted_opens[i].listen_port = 0;
1.333 markus 3346: permitted_opens[i].port_to_connect = 0;
1.336 millert 3347: free(permitted_opens[i].host_to_connect);
3348: permitted_opens[i].host_to_connect = NULL;
3349: free(permitted_opens[i].listen_host);
3350: permitted_opens[i].listen_host = NULL;
3351: permitted_opens[i].listen_path = NULL;
3352:
3353: return 0;
3354: }
3355:
3356: /*
3357: * Request cancellation of remote forwarding of Unix domain socket
3358: * path from local side.
3359: */
3360: static int
3361: channel_request_rforward_cancel_streamlocal(const char *path)
3362: {
3363: int i;
3364:
3365: if (!compat20)
3366: return -1;
3367:
3368: for (i = 0; i < num_permitted_opens; i++) {
3369: if (open_listen_match_streamlocal(&permitted_opens[i], path))
3370: break;
3371: }
3372: if (i >= num_permitted_opens) {
3373: debug("%s: requested forward not found", __func__);
3374: return -1;
3375: }
3376: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3377: packet_put_cstring("cancel-streamlocal-forward@openssh.com");
3378: packet_put_char(0);
3379: packet_put_cstring(path);
3380: packet_send();
3381:
1.202 djm 3382: permitted_opens[i].listen_port = 0;
1.336 millert 3383: permitted_opens[i].port_to_connect = 0;
1.321 djm 3384: free(permitted_opens[i].host_to_connect);
1.202 djm 3385: permitted_opens[i].host_to_connect = NULL;
1.333 markus 3386: permitted_opens[i].listen_host = NULL;
1.336 millert 3387: free(permitted_opens[i].listen_path);
3388: permitted_opens[i].listen_path = NULL;
1.312 djm 3389:
3390: return 0;
1.202 djm 3391: }
3392:
3393: /*
1.336 millert 3394: * Request cancellation of remote forwarding of a connection from local side.
3395: */
3396: int
3397: channel_request_rforward_cancel(struct Forward *fwd)
3398: {
3399: if (fwd->listen_path != NULL) {
3400: return (channel_request_rforward_cancel_streamlocal(
3401: fwd->listen_path));
3402: } else {
3403: return (channel_request_rforward_cancel_tcpip(fwd->listen_host,
3404: fwd->listen_port ? fwd->listen_port : fwd->allocated_port));
3405: }
3406: }
3407:
3408: /*
1.27 markus 3409: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
3410: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 3411: * message if there was an error).
1.27 markus 3412: */
1.253 markus 3413: int
1.336 millert 3414: channel_input_port_forward_request(int is_root, struct ForwardOptions *fwd_opts)
1.1 deraadt 3415: {
1.253 markus 3416: int success = 0;
1.336 millert 3417: struct Forward fwd;
1.1 deraadt 3418:
1.25 markus 3419: /* Get arguments from the packet. */
1.336 millert 3420: memset(&fwd, 0, sizeof(fwd));
3421: fwd.listen_port = packet_get_int();
3422: fwd.connect_host = packet_get_string(NULL);
3423: fwd.connect_port = packet_get_int();
1.25 markus 3424:
1.27 markus 3425: /*
3426: * Check that an unprivileged user is not trying to forward a
3427: * privileged port.
3428: */
1.336 millert 3429: if (fwd.listen_port < IPPORT_RESERVED && !is_root)
1.192 markus 3430: packet_disconnect(
3431: "Requested forwarding of port %d but user is not root.",
1.336 millert 3432: fwd.listen_port);
3433: if (fwd.connect_port == 0)
1.192 markus 3434: packet_disconnect("Dynamic forwarding denied.");
3435:
1.73 markus 3436: /* Initiate forwarding */
1.336 millert 3437: success = channel_setup_local_fwd_listener(&fwd, fwd_opts);
1.25 markus 3438:
3439: /* Free the argument string. */
1.336 millert 3440: free(fwd.connect_host);
1.253 markus 3441:
3442: return (success ? 0 : -1);
1.1 deraadt 3443: }
3444:
1.99 markus 3445: /*
3446: * Permits opening to any host/port if permitted_opens[] is empty. This is
3447: * usually called by the server, because the user could connect to any port
3448: * anyway, and the server has no way to know but to trust the client anyway.
3449: */
3450: void
1.142 itojun 3451: channel_permit_all_opens(void)
1.99 markus 3452: {
3453: if (num_permitted_opens == 0)
3454: all_opens_permitted = 1;
3455: }
3456:
1.101 markus 3457: void
1.99 markus 3458: channel_add_permitted_opens(char *host, int port)
3459: {
3460: debug("allow port forwarding to host %s port %d", host, port);
3461:
1.342 deraadt 3462: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3463: num_permitted_opens + 1, sizeof(*permitted_opens));
1.99 markus 3464: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
3465: permitted_opens[num_permitted_opens].port_to_connect = port;
1.333 markus 3466: permitted_opens[num_permitted_opens].listen_host = NULL;
1.336 millert 3467: permitted_opens[num_permitted_opens].listen_path = NULL;
1.333 markus 3468: permitted_opens[num_permitted_opens].listen_port = 0;
1.99 markus 3469: num_permitted_opens++;
3470:
3471: all_opens_permitted = 0;
1.315 markus 3472: }
3473:
3474: /*
3475: * Update the listen port for a dynamic remote forward, after
3476: * the actual 'newport' has been allocated. If 'newport' < 0 is
3477: * passed then they entry will be invalidated.
3478: */
3479: void
3480: channel_update_permitted_opens(int idx, int newport)
3481: {
3482: if (idx < 0 || idx >= num_permitted_opens) {
3483: debug("channel_update_permitted_opens: index out of range:"
3484: " %d num_permitted_opens %d", idx, num_permitted_opens);
3485: return;
3486: }
3487: debug("%s allowed port %d for forwarding to host %s port %d",
3488: newport > 0 ? "Updating" : "Removing",
3489: newport,
3490: permitted_opens[idx].host_to_connect,
3491: permitted_opens[idx].port_to_connect);
3492: if (newport >= 0) {
3493: permitted_opens[idx].listen_port =
3494: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3495: } else {
3496: permitted_opens[idx].listen_port = 0;
3497: permitted_opens[idx].port_to_connect = 0;
1.321 djm 3498: free(permitted_opens[idx].host_to_connect);
1.315 markus 3499: permitted_opens[idx].host_to_connect = NULL;
1.333 markus 3500: free(permitted_opens[idx].listen_host);
3501: permitted_opens[idx].listen_host = NULL;
1.336 millert 3502: free(permitted_opens[idx].listen_path);
3503: permitted_opens[idx].listen_path = NULL;
1.315 markus 3504: }
1.99 markus 3505: }
3506:
1.258 dtucker 3507: int
1.257 dtucker 3508: channel_add_adm_permitted_opens(char *host, int port)
3509: {
1.258 dtucker 3510: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 3511:
1.342 deraadt 3512: permitted_adm_opens = xreallocarray(permitted_adm_opens,
1.305 djm 3513: num_adm_permitted_opens + 1, sizeof(*permitted_adm_opens));
1.257 dtucker 3514: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
3515: = xstrdup(host);
3516: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.333 markus 3517: permitted_adm_opens[num_adm_permitted_opens].listen_host = NULL;
1.336 millert 3518: permitted_adm_opens[num_adm_permitted_opens].listen_path = NULL;
1.333 markus 3519: permitted_adm_opens[num_adm_permitted_opens].listen_port = 0;
1.258 dtucker 3520: return ++num_adm_permitted_opens;
1.257 dtucker 3521: }
3522:
3523: void
1.316 dtucker 3524: channel_disable_adm_local_opens(void)
3525: {
1.319 djm 3526: channel_clear_adm_permitted_opens();
1.343 dtucker 3527: permitted_adm_opens = xcalloc(sizeof(*permitted_adm_opens), 1);
1.319 djm 3528: permitted_adm_opens[num_adm_permitted_opens].host_to_connect = NULL;
3529: num_adm_permitted_opens = 1;
1.316 dtucker 3530: }
3531:
3532: void
1.99 markus 3533: channel_clear_permitted_opens(void)
3534: {
3535: int i;
3536:
1.333 markus 3537: for (i = 0; i < num_permitted_opens; i++) {
1.321 djm 3538: free(permitted_opens[i].host_to_connect);
1.333 markus 3539: free(permitted_opens[i].listen_host);
1.336 millert 3540: free(permitted_opens[i].listen_path);
1.333 markus 3541: }
1.321 djm 3542: free(permitted_opens);
3543: permitted_opens = NULL;
1.99 markus 3544: num_permitted_opens = 0;
1.257 dtucker 3545: }
3546:
3547: void
3548: channel_clear_adm_permitted_opens(void)
3549: {
3550: int i;
1.99 markus 3551:
1.333 markus 3552: for (i = 0; i < num_adm_permitted_opens; i++) {
1.321 djm 3553: free(permitted_adm_opens[i].host_to_connect);
1.333 markus 3554: free(permitted_adm_opens[i].listen_host);
1.336 millert 3555: free(permitted_adm_opens[i].listen_path);
1.333 markus 3556: }
1.321 djm 3557: free(permitted_adm_opens);
3558: permitted_adm_opens = NULL;
1.257 dtucker 3559: num_adm_permitted_opens = 0;
1.278 dtucker 3560: }
3561:
3562: void
3563: channel_print_adm_permitted_opens(void)
3564: {
1.286 djm 3565: int i;
1.278 dtucker 3566:
1.290 stevesk 3567: printf("permitopen");
1.288 stevesk 3568: if (num_adm_permitted_opens == 0) {
1.290 stevesk 3569: printf(" any\n");
1.288 stevesk 3570: return;
3571: }
1.278 dtucker 3572: for (i = 0; i < num_adm_permitted_opens; i++)
1.316 dtucker 3573: if (permitted_adm_opens[i].host_to_connect == NULL)
3574: printf(" none");
3575: else
1.278 dtucker 3576: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
3577: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 3578: printf("\n");
1.99 markus 3579: }
3580:
1.314 dtucker 3581: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3582: int
3583: permitopen_port(const char *p)
3584: {
3585: int port;
3586:
3587: if (strcmp(p, "*") == 0)
3588: return FWD_PERMIT_ANY_PORT;
3589: if ((port = a2port(p)) > 0)
3590: return port;
3591: return -1;
3592: }
3593:
1.276 djm 3594: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3595: static int
1.276 djm 3596: connect_next(struct channel_connect *cctx)
1.41 markus 3597: {
1.276 djm 3598: int sock, saved_errno;
1.336 millert 3599: struct sockaddr_un *sunaddr;
1.352 ! deraadt 3600: char ntop[NI_MAXHOST], strport[MAXIMUM(NI_MAXSERV,sizeof(sunaddr->sun_path))];
1.41 markus 3601:
1.276 djm 3602: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3603: switch (cctx->ai->ai_family) {
3604: case AF_UNIX:
3605: /* unix:pathname instead of host:port */
3606: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3607: strlcpy(ntop, "unix", sizeof(ntop));
3608: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3609: break;
3610: case AF_INET:
3611: case AF_INET6:
3612: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3613: ntop, sizeof(ntop), strport, sizeof(strport),
3614: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3615: error("connect_next: getnameinfo failed");
3616: continue;
3617: }
3618: break;
3619: default:
1.41 markus 3620: continue;
3621: }
1.300 dtucker 3622: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3623: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3624: if (cctx->ai->ai_next == NULL)
1.186 djm 3625: error("socket: %.100s", strerror(errno));
3626: else
3627: verbose("socket: %.100s", strerror(errno));
1.41 markus 3628: continue;
3629: }
1.205 djm 3630: if (set_nonblock(sock) == -1)
3631: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3632: if (connect(sock, cctx->ai->ai_addr,
3633: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3634: debug("connect_next: host %.100s ([%.100s]:%s): "
3635: "%.100s", cctx->host, ntop, strport,
1.41 markus 3636: strerror(errno));
1.276 djm 3637: saved_errno = errno;
1.41 markus 3638: close(sock);
1.276 djm 3639: errno = saved_errno;
1.89 stevesk 3640: continue; /* fail -- try next */
1.41 markus 3641: }
1.336 millert 3642: if (cctx->ai->ai_family != AF_UNIX)
3643: set_nodelay(sock);
1.276 djm 3644: debug("connect_next: host %.100s ([%.100s]:%s) "
3645: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3646: cctx->ai = cctx->ai->ai_next;
3647: return sock;
3648: }
3649: return -1;
3650: }
1.41 markus 3651:
1.276 djm 3652: static void
3653: channel_connect_ctx_free(struct channel_connect *cctx)
3654: {
1.321 djm 3655: free(cctx->host);
1.336 millert 3656: if (cctx->aitop) {
3657: if (cctx->aitop->ai_family == AF_UNIX)
3658: free(cctx->aitop);
3659: else
3660: freeaddrinfo(cctx->aitop);
3661: }
1.329 tedu 3662: memset(cctx, 0, sizeof(*cctx));
1.276 djm 3663: }
3664:
1.336 millert 3665: /* Return CONNECTING channel to remote host:port or local socket path */
1.276 djm 3666: static Channel *
1.336 millert 3667: connect_to(const char *name, int port, char *ctype, char *rname)
1.276 djm 3668: {
3669: struct addrinfo hints;
3670: int gaierr;
3671: int sock = -1;
3672: char strport[NI_MAXSERV];
3673: struct channel_connect cctx;
3674: Channel *c;
3675:
1.284 djm 3676: memset(&cctx, 0, sizeof(cctx));
1.336 millert 3677:
3678: if (port == PORT_STREAMLOCAL) {
3679: struct sockaddr_un *sunaddr;
3680: struct addrinfo *ai;
3681:
3682: if (strlen(name) > sizeof(sunaddr->sun_path)) {
3683: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
3684: return (NULL);
3685: }
3686:
3687: /*
3688: * Fake up a struct addrinfo for AF_UNIX connections.
3689: * channel_connect_ctx_free() must check ai_family
3690: * and use free() not freeaddirinfo() for AF_UNIX.
3691: */
3692: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
3693: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
3694: ai->ai_addr = (struct sockaddr *)(ai + 1);
3695: ai->ai_addrlen = sizeof(*sunaddr);
3696: ai->ai_family = AF_UNIX;
3697: ai->ai_socktype = SOCK_STREAM;
3698: ai->ai_protocol = PF_UNSPEC;
3699: sunaddr = (struct sockaddr_un *)ai->ai_addr;
3700: sunaddr->sun_family = AF_UNIX;
3701: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
3702: cctx.aitop = ai;
3703: } else {
3704: memset(&hints, 0, sizeof(hints));
3705: hints.ai_family = IPv4or6;
3706: hints.ai_socktype = SOCK_STREAM;
3707: snprintf(strport, sizeof strport, "%d", port);
3708: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx.aitop)) != 0) {
3709: error("connect_to %.100s: unknown host (%s)", name,
3710: ssh_gai_strerror(gaierr));
3711: return NULL;
3712: }
1.41 markus 3713: }
1.276 djm 3714:
1.336 millert 3715: cctx.host = xstrdup(name);
1.276 djm 3716: cctx.port = port;
3717: cctx.ai = cctx.aitop;
3718:
3719: if ((sock = connect_next(&cctx)) == -1) {
3720: error("connect to %.100s port %d failed: %s",
1.336 millert 3721: name, port, strerror(errno));
1.276 djm 3722: channel_connect_ctx_free(&cctx);
3723: return NULL;
1.41 markus 3724: }
1.276 djm 3725: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
3726: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
3727: c->connect_ctx = cctx;
3728: return c;
1.41 markus 3729: }
1.99 markus 3730:
1.276 djm 3731: Channel *
1.333 markus 3732: channel_connect_by_listen_address(const char *listen_host,
3733: u_short listen_port, char *ctype, char *rname)
1.73 markus 3734: {
3735: int i;
1.99 markus 3736:
1.276 djm 3737: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3738: if (open_listen_match_tcpip(&permitted_opens[i], listen_host,
1.333 markus 3739: listen_port, 1)) {
1.99 markus 3740: return connect_to(
1.73 markus 3741: permitted_opens[i].host_to_connect,
1.276 djm 3742: permitted_opens[i].port_to_connect, ctype, rname);
3743: }
3744: }
1.74 markus 3745: error("WARNING: Server requests forwarding for unknown listen_port %d",
3746: listen_port);
1.276 djm 3747: return NULL;
1.73 markus 3748: }
3749:
1.336 millert 3750: Channel *
3751: channel_connect_by_listen_path(const char *path, char *ctype, char *rname)
3752: {
3753: int i;
3754:
3755: for (i = 0; i < num_permitted_opens; i++) {
3756: if (open_listen_match_streamlocal(&permitted_opens[i], path)) {
3757: return connect_to(
3758: permitted_opens[i].host_to_connect,
3759: permitted_opens[i].port_to_connect, ctype, rname);
3760: }
3761: }
3762: error("WARNING: Server requests forwarding for unknown path %.100s",
3763: path);
3764: return NULL;
3765: }
3766:
1.99 markus 3767: /* Check if connecting to that port is permitted and connect. */
1.276 djm 3768: Channel *
1.336 millert 3769: channel_connect_to_port(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 3770: {
1.257 dtucker 3771: int i, permit, permit_adm = 1;
1.99 markus 3772:
3773: permit = all_opens_permitted;
3774: if (!permit) {
3775: for (i = 0; i < num_permitted_opens; i++)
1.333 markus 3776: if (open_match(&permitted_opens[i], host, port)) {
1.99 markus 3777: permit = 1;
1.333 markus 3778: break;
3779: }
1.257 dtucker 3780: }
1.99 markus 3781:
1.257 dtucker 3782: if (num_adm_permitted_opens > 0) {
3783: permit_adm = 0;
3784: for (i = 0; i < num_adm_permitted_opens; i++)
1.333 markus 3785: if (open_match(&permitted_adm_opens[i], host, port)) {
1.257 dtucker 3786: permit_adm = 1;
1.333 markus 3787: break;
3788: }
1.99 markus 3789: }
1.257 dtucker 3790:
3791: if (!permit || !permit_adm) {
1.188 itojun 3792: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3793: "but the request was denied.", host, port);
1.276 djm 3794: return NULL;
1.99 markus 3795: }
1.276 djm 3796: return connect_to(host, port, ctype, rname);
1.336 millert 3797: }
3798:
3799: /* Check if connecting to that path is permitted and connect. */
3800: Channel *
3801: channel_connect_to_path(const char *path, char *ctype, char *rname)
3802: {
3803: int i, permit, permit_adm = 1;
3804:
3805: permit = all_opens_permitted;
3806: if (!permit) {
3807: for (i = 0; i < num_permitted_opens; i++)
3808: if (open_match(&permitted_opens[i], path, PORT_STREAMLOCAL)) {
3809: permit = 1;
3810: break;
3811: }
3812: }
3813:
3814: if (num_adm_permitted_opens > 0) {
3815: permit_adm = 0;
3816: for (i = 0; i < num_adm_permitted_opens; i++)
3817: if (open_match(&permitted_adm_opens[i], path, PORT_STREAMLOCAL)) {
3818: permit_adm = 1;
3819: break;
3820: }
3821: }
3822:
3823: if (!permit || !permit_adm) {
3824: logit("Received request to connect to path %.100s, "
3825: "but the request was denied.", path);
3826: return NULL;
3827: }
3828: return connect_to(path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 3829: }
3830:
3831: void
3832: channel_send_window_changes(void)
3833: {
1.209 avsm 3834: u_int i;
1.204 djm 3835: struct winsize ws;
3836:
3837: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3838: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3839: channels[i]->type != SSH_CHANNEL_OPEN)
3840: continue;
3841: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3842: continue;
3843: channel_request_start(i, "window-change", 0);
1.238 deraadt 3844: packet_put_int((u_int)ws.ws_col);
3845: packet_put_int((u_int)ws.ws_row);
3846: packet_put_int((u_int)ws.ws_xpixel);
3847: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3848: packet_send();
3849: }
1.99 markus 3850: }
3851:
1.121 markus 3852: /* -- X11 forwarding */
1.1 deraadt 3853:
1.27 markus 3854: /*
3855: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3856: * Returns 0 and a suitable display number for the DISPLAY variable
3857: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3858: */
1.141 stevesk 3859: int
1.163 stevesk 3860: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3861: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3862: {
1.149 markus 3863: Channel *nc = NULL;
1.31 markus 3864: int display_number, sock;
3865: u_short port;
1.35 markus 3866: struct addrinfo hints, *ai, *aitop;
3867: char strport[NI_MAXSERV];
3868: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3869:
1.224 markus 3870: if (chanids == NULL)
3871: return -1;
3872:
1.33 markus 3873: for (display_number = x11_display_offset;
1.148 deraadt 3874: display_number < MAX_DISPLAYS;
3875: display_number++) {
1.25 markus 3876: port = 6000 + display_number;
1.35 markus 3877: memset(&hints, 0, sizeof(hints));
3878: hints.ai_family = IPv4or6;
1.163 stevesk 3879: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3880: hints.ai_socktype = SOCK_STREAM;
3881: snprintf(strport, sizeof strport, "%d", port);
3882: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3883: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3884: return -1;
1.25 markus 3885: }
1.35 markus 3886: for (ai = aitop; ai; ai = ai->ai_next) {
3887: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3888: continue;
1.300 dtucker 3889: sock = socket(ai->ai_family, ai->ai_socktype,
3890: ai->ai_protocol);
1.35 markus 3891: if (sock < 0) {
3892: error("socket: %.100s", strerror(errno));
1.203 markus 3893: freeaddrinfo(aitop);
1.141 stevesk 3894: return -1;
1.35 markus 3895: }
1.226 djm 3896: channel_set_reuseaddr(sock);
1.35 markus 3897: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3898: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3899: close(sock);
1.183 itojun 3900:
1.35 markus 3901: for (n = 0; n < num_socks; n++) {
3902: close(socks[n]);
3903: }
3904: num_socks = 0;
3905: break;
3906: }
3907: socks[num_socks++] = sock;
3908: if (num_socks == NUM_SOCKS)
3909: break;
1.25 markus 3910: }
1.83 stevesk 3911: freeaddrinfo(aitop);
1.35 markus 3912: if (num_socks > 0)
3913: break;
1.25 markus 3914: }
3915: if (display_number >= MAX_DISPLAYS) {
3916: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3917: return -1;
1.25 markus 3918: }
3919: /* Start listening for connections on the socket. */
1.35 markus 3920: for (n = 0; n < num_socks; n++) {
3921: sock = socks[n];
1.199 markus 3922: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3923: error("listen: %.100s", strerror(errno));
3924: close(sock);
1.141 stevesk 3925: return -1;
1.35 markus 3926: }
1.25 markus 3927: }
1.35 markus 3928:
3929: /* Allocate a channel for each socket. */
1.242 djm 3930: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3931: for (n = 0; n < num_socks; n++) {
3932: sock = socks[n];
1.149 markus 3933: nc = channel_new("x11 listener",
1.51 markus 3934: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3935: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3936: 0, "X11 inet listener", 1);
1.167 markus 3937: nc->single_connection = single_connection;
1.224 markus 3938: (*chanids)[n] = nc->self;
1.35 markus 3939: }
1.224 markus 3940: (*chanids)[n] = -1;
1.1 deraadt 3941:
1.141 stevesk 3942: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3943: *display_numberp = display_number;
3944: return (0);
1.1 deraadt 3945: }
3946:
1.127 itojun 3947: static int
1.77 markus 3948: connect_local_xsocket(u_int dnr)
1.1 deraadt 3949: {
1.25 markus 3950: int sock;
3951: struct sockaddr_un addr;
3952:
1.147 stevesk 3953: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3954: if (sock < 0)
3955: error("socket: %.100s", strerror(errno));
3956: memset(&addr, 0, sizeof(addr));
3957: addr.sun_family = AF_UNIX;
3958: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3959: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3960: return sock;
3961: close(sock);
1.25 markus 3962: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3963: return -1;
1.1 deraadt 3964: }
3965:
1.51 markus 3966: int
3967: x11_connect_display(void)
1.1 deraadt 3968: {
1.248 deraadt 3969: u_int display_number;
1.25 markus 3970: const char *display;
1.51 markus 3971: char buf[1024], *cp;
1.35 markus 3972: struct addrinfo hints, *ai, *aitop;
3973: char strport[NI_MAXSERV];
1.248 deraadt 3974: int gaierr, sock = 0;
1.25 markus 3975:
3976: /* Try to open a socket for the local X server. */
3977: display = getenv("DISPLAY");
3978: if (!display) {
3979: error("DISPLAY not set.");
1.51 markus 3980: return -1;
1.25 markus 3981: }
1.27 markus 3982: /*
3983: * Now we decode the value of the DISPLAY variable and make a
3984: * connection to the real X server.
3985: */
3986:
3987: /*
3988: * Check if it is a unix domain socket. Unix domain displays are in
3989: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3990: */
1.25 markus 3991: if (strncmp(display, "unix:", 5) == 0 ||
3992: display[0] == ':') {
3993: /* Connect to the unix domain socket. */
1.248 deraadt 3994: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3995: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3996: display);
1.51 markus 3997: return -1;
1.25 markus 3998: }
3999: /* Create a socket. */
4000: sock = connect_local_xsocket(display_number);
4001: if (sock < 0)
1.51 markus 4002: return -1;
1.25 markus 4003:
4004: /* OK, we now have a connection to the display. */
1.51 markus 4005: return sock;
1.25 markus 4006: }
1.27 markus 4007: /*
4008: * Connect to an inet socket. The DISPLAY value is supposedly
4009: * hostname:d[.s], where hostname may also be numeric IP address.
4010: */
1.145 stevesk 4011: strlcpy(buf, display, sizeof(buf));
1.25 markus 4012: cp = strchr(buf, ':');
4013: if (!cp) {
4014: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4015: return -1;
1.25 markus 4016: }
4017: *cp = 0;
1.27 markus 4018: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 4019: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4020: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4021: display);
1.51 markus 4022: return -1;
1.25 markus 4023: }
1.35 markus 4024:
4025: /* Look up the host address */
4026: memset(&hints, 0, sizeof(hints));
4027: hints.ai_family = IPv4or6;
4028: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4029: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4030: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4031: error("%.100s: unknown host. (%s)", buf,
4032: ssh_gai_strerror(gaierr));
1.51 markus 4033: return -1;
1.25 markus 4034: }
1.35 markus 4035: for (ai = aitop; ai; ai = ai->ai_next) {
4036: /* Create a socket. */
1.300 dtucker 4037: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4038: if (sock < 0) {
1.194 markus 4039: debug2("socket: %.100s", strerror(errno));
1.41 markus 4040: continue;
4041: }
4042: /* Connect it to the display. */
4043: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4044: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4045: 6000 + display_number, strerror(errno));
4046: close(sock);
4047: continue;
4048: }
4049: /* Success */
4050: break;
1.35 markus 4051: }
4052: freeaddrinfo(aitop);
4053: if (!ai) {
1.248 deraadt 4054: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 4055: strerror(errno));
1.51 markus 4056: return -1;
1.25 markus 4057: }
1.162 stevesk 4058: set_nodelay(sock);
1.51 markus 4059: return sock;
4060: }
4061:
4062: /*
4063: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
4064: * the remote channel number. We should do whatever we want, and respond
4065: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
4066: */
4067:
1.259 stevesk 4068: /* ARGSUSED */
1.339 markus 4069: int
1.154 markus 4070: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 4071: {
1.113 markus 4072: Channel *c = NULL;
4073: int remote_id, sock = 0;
1.51 markus 4074: char *remote_host;
1.25 markus 4075:
1.113 markus 4076: debug("Received X11 open request.");
1.51 markus 4077:
1.113 markus 4078: remote_id = packet_get_int();
1.121 markus 4079:
4080: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 4081: remote_host = packet_get_string(NULL);
1.51 markus 4082: } else {
4083: remote_host = xstrdup("unknown (remote did not supply name)");
4084: }
1.152 markus 4085: packet_check_eom();
1.25 markus 4086:
1.51 markus 4087: /* Obtain a connection to the real X display. */
4088: sock = x11_connect_display();
1.113 markus 4089: if (sock != -1) {
4090: /* Allocate a channel for this connection. */
4091: c = channel_new("connected x11 socket",
4092: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
4093: remote_host, 1);
1.167 markus 4094: c->remote_id = remote_id;
4095: c->force_drain = 1;
1.113 markus 4096: }
1.321 djm 4097: free(remote_host);
1.113 markus 4098: if (c == NULL) {
1.51 markus 4099: /* Send refusal to the remote host. */
4100: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 4101: packet_put_int(remote_id);
1.51 markus 4102: } else {
4103: /* Send a confirmation to the remote host. */
4104: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 4105: packet_put_int(remote_id);
4106: packet_put_int(c->self);
1.51 markus 4107: }
1.113 markus 4108: packet_send();
1.339 markus 4109: return 0;
1.72 markus 4110: }
4111:
4112: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 4113: /* ARGSUSED */
1.339 markus 4114: int
1.154 markus 4115: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 4116: {
4117: int rchan = packet_get_int();
1.180 deraadt 4118:
1.143 deraadt 4119: switch (type) {
1.72 markus 4120: case SSH_SMSG_AGENT_OPEN:
4121: error("Warning: ssh server tried agent forwarding.");
4122: break;
4123: case SSH_SMSG_X11_OPEN:
4124: error("Warning: ssh server tried X11 forwarding.");
4125: break;
4126: default:
1.154 markus 4127: error("deny_input_open: type %d", type);
1.72 markus 4128: break;
4129: }
1.230 stevesk 4130: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 4131: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
4132: packet_put_int(rchan);
4133: packet_send();
1.339 markus 4134: return 0;
1.1 deraadt 4135: }
4136:
1.27 markus 4137: /*
4138: * Requests forwarding of X11 connections, generates fake authentication
4139: * data, and enables authentication spoofing.
1.121 markus 4140: * This should be called in the client only.
1.27 markus 4141: */
1.49 markus 4142: void
1.215 djm 4143: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.311 djm 4144: const char *proto, const char *data, int want_reply)
1.1 deraadt 4145: {
1.77 markus 4146: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4147: u_int i, value;
1.25 markus 4148: char *new_data;
4149: int screen_number;
4150: const char *cp;
1.207 avsm 4151: u_int32_t rnd = 0;
1.25 markus 4152:
1.220 markus 4153: if (x11_saved_display == NULL)
4154: x11_saved_display = xstrdup(disp);
4155: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 4156: error("x11_request_forwarding_with_spoofing: different "
4157: "$DISPLAY already forwarded");
4158: return;
4159: }
4160:
1.266 djm 4161: cp = strchr(disp, ':');
1.25 markus 4162: if (cp)
4163: cp = strchr(cp, '.');
4164: if (cp)
1.245 deraadt 4165: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4166: else
4167: screen_number = 0;
4168:
1.219 djm 4169: if (x11_saved_proto == NULL) {
4170: /* Save protocol name. */
4171: x11_saved_proto = xstrdup(proto);
4172: /*
1.221 djm 4173: * Extract real authentication data and generate fake data
1.219 djm 4174: * of the same length.
4175: */
4176: x11_saved_data = xmalloc(data_len);
4177: x11_fake_data = xmalloc(data_len);
4178: for (i = 0; i < data_len; i++) {
4179: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4180: fatal("x11_request_forwarding: bad "
4181: "authentication data: %.100s", data);
4182: if (i % 4 == 0)
4183: rnd = arc4random();
4184: x11_saved_data[i] = value;
4185: x11_fake_data[i] = rnd & 0xff;
4186: rnd >>= 8;
4187: }
4188: x11_saved_data_len = data_len;
4189: x11_fake_data_len = data_len;
1.25 markus 4190: }
4191:
4192: /* Convert the fake data into hex. */
1.219 djm 4193: new_data = tohex(x11_fake_data, data_len);
1.25 markus 4194:
4195: /* Send the request packet. */
1.51 markus 4196: if (compat20) {
1.311 djm 4197: channel_request_start(client_session_id, "x11-req", want_reply);
1.51 markus 4198: packet_put_char(0); /* XXX bool single connection */
4199: } else {
4200: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
4201: }
4202: packet_put_cstring(proto);
4203: packet_put_cstring(new_data);
1.25 markus 4204: packet_put_int(screen_number);
4205: packet_send();
4206: packet_write_wait();
1.321 djm 4207: free(new_data);
1.1 deraadt 4208: }
4209:
1.121 markus 4210:
4211: /* -- agent forwarding */
4212:
1.1 deraadt 4213: /* Sends a message to the server to request authentication fd forwarding. */
4214:
1.49 markus 4215: void
1.142 itojun 4216: auth_request_forwarding(void)
1.1 deraadt 4217: {
1.25 markus 4218: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
4219: packet_send();
4220: packet_write_wait();
1.1 deraadt 4221: }
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