Annotation of src/usr.bin/ssh/channels.c, Revision 1.346
1.346 ! djm 1: /* $OpenBSD: channels.c,v 1.345 2015/06/30 05:23:25 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.340 deraadt 43: #include <sys/param.h> /* MIN MAX */
1.336 millert 44: #include <sys/stat.h>
1.234 stevesk 45: #include <sys/ioctl.h>
1.235 stevesk 46: #include <sys/un.h>
1.251 stevesk 47: #include <sys/socket.h>
1.261 stevesk 48: #include <sys/time.h>
1.275 djm 49: #include <sys/queue.h>
1.251 stevesk 50:
51: #include <netinet/in.h>
52: #include <arpa/inet.h>
1.233 stevesk 53:
1.254 stevesk 54: #include <errno.h>
1.298 dtucker 55: #include <fcntl.h>
1.255 stevesk 56: #include <netdb.h>
1.341 millert 57: #include <stdint.h>
1.263 stevesk 58: #include <stdio.h>
1.262 stevesk 59: #include <stdlib.h>
1.260 stevesk 60: #include <string.h>
1.233 stevesk 61: #include <termios.h>
1.256 stevesk 62: #include <unistd.h>
1.265 deraadt 63: #include <stdarg.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh1.h"
68: #include "ssh2.h"
1.1 deraadt 69: #include "packet.h"
1.82 markus 70: #include "log.h"
71: #include "misc.h"
1.265 deraadt 72: #include "buffer.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.64 markus 76: #include "key.h"
77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.1 deraadt 79:
1.121 markus 80: /* -- channel core */
1.12 markus 81:
1.27 markus 82: /*
83: * Pointer to an array containing all allocated channels. The array is
84: * dynamically extended as needed.
85: */
1.113 markus 86: static Channel **channels = NULL;
1.1 deraadt 87:
1.27 markus 88: /*
89: * Size of the channel array. All slots of the array must always be
1.113 markus 90: * initialized (at least the type field); unused slots set to NULL
1.27 markus 91: */
1.209 avsm 92: static u_int channels_alloc = 0;
1.1 deraadt 93:
1.27 markus 94: /*
95: * Maximum file descriptor value used in any of the channels. This is
1.113 markus 96: * updated in channel_new.
1.27 markus 97: */
1.84 markus 98: static int channel_max_fd = 0;
1.1 deraadt 99:
100:
1.121 markus 101: /* -- tcp forwarding */
1.1 deraadt 102:
1.27 markus 103: /*
104: * Data structure for storing which hosts are permitted for forward requests.
105: * The local sides of any remote forwards are stored in this array to prevent
106: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
107: * network (which might be behind a firewall).
108: */
1.336 millert 109: /* XXX: streamlocal wants a path instead of host:port */
110: /* Overload host_to_connect; we could just make this match Forward */
111: /* XXX - can we use listen_host instead of listen_path? */
1.25 markus 112: typedef struct {
1.41 markus 113: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 114: int port_to_connect; /* Connect to 'port'. */
1.333 markus 115: char *listen_host; /* Remote side should listen address. */
1.336 millert 116: char *listen_path; /* Remote side should listen path. */
117: int listen_port; /* Remote side should listen port. */
1.1 deraadt 118: } ForwardPermission;
119:
1.257 dtucker 120: /* List of all permitted host/port pairs to connect by the user. */
1.305 djm 121: static ForwardPermission *permitted_opens = NULL;
1.121 markus 122:
1.257 dtucker 123: /* List of all permitted host/port pairs to connect by the admin. */
1.305 djm 124: static ForwardPermission *permitted_adm_opens = NULL;
1.257 dtucker 125:
126: /* Number of permitted host/port pairs in the array permitted by the user. */
1.1 deraadt 127: static int num_permitted_opens = 0;
1.257 dtucker 128:
129: /* Number of permitted host/port pair in the array permitted by the admin. */
130: static int num_adm_permitted_opens = 0;
131:
1.314 dtucker 132: /* special-case port number meaning allow any port */
133: #define FWD_PERMIT_ANY_PORT 0
134:
1.27 markus 135: /*
136: * If this is true, all opens are permitted. This is the case on the server
137: * on which we have to trust the client anyway, and the user could do
138: * anything after logging in anyway.
139: */
1.1 deraadt 140: static int all_opens_permitted = 0;
141:
1.121 markus 142:
143: /* -- X11 forwarding */
144:
145: /* Maximum number of fake X11 displays to try. */
146: #define MAX_DISPLAYS 1000
147:
1.219 djm 148: /* Saved X11 local (client) display. */
149: static char *x11_saved_display = NULL;
150:
1.121 markus 151: /* Saved X11 authentication protocol name. */
152: static char *x11_saved_proto = NULL;
153:
154: /* Saved X11 authentication data. This is the real data. */
155: static char *x11_saved_data = NULL;
156: static u_int x11_saved_data_len = 0;
157:
158: /*
159: * Fake X11 authentication data. This is what the server will be sending us;
160: * we should replace any occurrences of this by the real data.
161: */
1.240 deraadt 162: static u_char *x11_fake_data = NULL;
1.121 markus 163: static u_int x11_fake_data_len;
164:
165:
166: /* -- agent forwarding */
167:
168: #define NUM_SOCKS 10
169:
1.82 markus 170: /* AF_UNSPEC or AF_INET or AF_INET6 */
1.135 markus 171: static int IPv4or6 = AF_UNSPEC;
1.1 deraadt 172:
1.121 markus 173: /* helper */
1.127 itojun 174: static void port_open_helper(Channel *c, char *rtype);
1.103 markus 175:
1.276 djm 176: /* non-blocking connect helpers */
177: static int connect_next(struct channel_connect *);
178: static void channel_connect_ctx_free(struct channel_connect *);
179:
1.121 markus 180: /* -- channel core */
1.41 markus 181:
182: Channel *
1.229 markus 183: channel_by_id(int id)
1.41 markus 184: {
185: Channel *c;
1.113 markus 186:
1.209 avsm 187: if (id < 0 || (u_int)id >= channels_alloc) {
1.229 markus 188: logit("channel_by_id: %d: bad id", id);
1.41 markus 189: return NULL;
190: }
1.113 markus 191: c = channels[id];
192: if (c == NULL) {
1.229 markus 193: logit("channel_by_id: %d: bad id: channel free", id);
1.41 markus 194: return NULL;
195: }
196: return c;
1.55 markus 197: }
198:
1.27 markus 199: /*
1.229 markus 200: * Returns the channel if it is allowed to receive protocol messages.
201: * Private channels, like listening sockets, may not receive messages.
202: */
203: Channel *
204: channel_lookup(int id)
205: {
206: Channel *c;
207:
208: if ((c = channel_by_id(id)) == NULL)
209: return (NULL);
210:
1.237 deraadt 211: switch (c->type) {
1.229 markus 212: case SSH_CHANNEL_X11_OPEN:
213: case SSH_CHANNEL_LARVAL:
214: case SSH_CHANNEL_CONNECTING:
215: case SSH_CHANNEL_DYNAMIC:
216: case SSH_CHANNEL_OPENING:
217: case SSH_CHANNEL_OPEN:
218: case SSH_CHANNEL_INPUT_DRAINING:
219: case SSH_CHANNEL_OUTPUT_DRAINING:
1.323 dtucker 220: case SSH_CHANNEL_ABANDONED:
1.229 markus 221: return (c);
222: }
223: logit("Non-public channel %d, type %d.", id, c->type);
224: return (NULL);
225: }
226:
227: /*
1.55 markus 228: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 229: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 230: */
1.127 itojun 231: static void
1.71 markus 232: channel_register_fds(Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 233: int extusage, int nonblock, int is_tty)
1.1 deraadt 234: {
1.25 markus 235: /* Update the maximum file descriptor value. */
1.84 markus 236: channel_max_fd = MAX(channel_max_fd, rfd);
237: channel_max_fd = MAX(channel_max_fd, wfd);
238: channel_max_fd = MAX(channel_max_fd, efd);
239:
1.298 dtucker 240: if (rfd != -1)
241: fcntl(rfd, F_SETFD, FD_CLOEXEC);
242: if (wfd != -1 && wfd != rfd)
243: fcntl(wfd, F_SETFD, FD_CLOEXEC);
244: if (efd != -1 && efd != rfd && efd != wfd)
245: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 246:
1.52 markus 247: c->rfd = rfd;
248: c->wfd = wfd;
249: c->sock = (rfd == wfd) ? rfd : -1;
250: c->efd = efd;
251: c->extended_usage = extusage;
1.71 markus 252:
1.282 dtucker 253: if ((c->isatty = is_tty) != 0)
1.194 markus 254: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 255:
1.71 markus 256: /* enable nonblocking mode */
257: if (nonblock) {
258: if (rfd != -1)
259: set_nonblock(rfd);
260: if (wfd != -1)
261: set_nonblock(wfd);
262: if (efd != -1)
263: set_nonblock(efd);
264: }
1.52 markus 265: }
266:
267: /*
268: * Allocate a new channel object and set its type and socket. This will cause
269: * remote_name to be freed.
270: */
1.113 markus 271: Channel *
1.52 markus 272: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 273: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 274: {
1.209 avsm 275: int found;
276: u_int i;
1.52 markus 277: Channel *c;
1.25 markus 278:
279: /* Do initial allocation if this is the first call. */
280: if (channels_alloc == 0) {
281: channels_alloc = 10;
1.242 djm 282: channels = xcalloc(channels_alloc, sizeof(Channel *));
1.25 markus 283: for (i = 0; i < channels_alloc; i++)
1.113 markus 284: channels[i] = NULL;
1.25 markus 285: }
286: /* Try to find a free slot where to put the new channel. */
287: for (found = -1, i = 0; i < channels_alloc; i++)
1.113 markus 288: if (channels[i] == NULL) {
1.25 markus 289: /* Found a free slot. */
1.209 avsm 290: found = (int)i;
1.25 markus 291: break;
292: }
1.209 avsm 293: if (found < 0) {
1.27 markus 294: /* There are no free slots. Take last+1 slot and expand the array. */
1.25 markus 295: found = channels_alloc;
1.179 markus 296: if (channels_alloc > 10000)
297: fatal("channel_new: internal error: channels_alloc %d "
298: "too big.", channels_alloc);
1.342 deraadt 299: channels = xreallocarray(channels, channels_alloc + 10,
1.243 djm 300: sizeof(Channel *));
1.195 markus 301: channels_alloc += 10;
1.70 markus 302: debug2("channel: expanding %d", channels_alloc);
1.25 markus 303: for (i = found; i < channels_alloc; i++)
1.113 markus 304: channels[i] = NULL;
1.25 markus 305: }
1.113 markus 306: /* Initialize and return new channel. */
1.242 djm 307: c = channels[found] = xcalloc(1, sizeof(Channel));
1.25 markus 308: buffer_init(&c->input);
309: buffer_init(&c->output);
1.41 markus 310: buffer_init(&c->extended);
1.293 djm 311: c->path = NULL;
1.312 djm 312: c->listening_addr = NULL;
313: c->listening_port = 0;
1.159 markus 314: c->ostate = CHAN_OUTPUT_OPEN;
315: c->istate = CHAN_INPUT_OPEN;
316: c->flags = 0;
1.281 djm 317: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0);
1.317 djm 318: c->notbefore = 0;
1.25 markus 319: c->self = found;
320: c->type = type;
1.41 markus 321: c->ctype = ctype;
1.51 markus 322: c->local_window = window;
323: c->local_window_max = window;
324: c->local_consumed = 0;
325: c->local_maxpacket = maxpack;
1.25 markus 326: c->remote_id = -1;
1.190 markus 327: c->remote_name = xstrdup(remote_name);
1.41 markus 328: c->remote_window = 0;
329: c->remote_maxpacket = 0;
1.133 markus 330: c->force_drain = 0;
1.149 markus 331: c->single_connection = 0;
1.131 markus 332: c->detach_user = NULL;
1.225 djm 333: c->detach_close = 0;
1.275 djm 334: c->open_confirm = NULL;
335: c->open_confirm_ctx = NULL;
1.65 markus 336: c->input_filter = NULL;
1.231 reyk 337: c->output_filter = NULL;
1.280 djm 338: c->filter_ctx = NULL;
339: c->filter_cleanup = NULL;
1.302 djm 340: c->ctl_chan = -1;
341: c->mux_rcb = NULL;
342: c->mux_ctx = NULL;
1.304 djm 343: c->mux_pause = 0;
1.299 markus 344: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 345: TAILQ_INIT(&c->status_confirms);
1.25 markus 346: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 347: return c;
1.1 deraadt 348: }
1.52 markus 349:
1.132 markus 350: static int
351: channel_find_maxfd(void)
352: {
1.209 avsm 353: u_int i;
354: int max = 0;
1.132 markus 355: Channel *c;
356:
357: for (i = 0; i < channels_alloc; i++) {
358: c = channels[i];
359: if (c != NULL) {
360: max = MAX(max, c->rfd);
361: max = MAX(max, c->wfd);
362: max = MAX(max, c->efd);
363: }
364: }
365: return max;
366: }
367:
368: int
369: channel_close_fd(int *fdp)
370: {
371: int ret = 0, fd = *fdp;
372:
373: if (fd != -1) {
374: ret = close(fd);
375: *fdp = -1;
376: if (fd == channel_max_fd)
377: channel_max_fd = channel_find_maxfd();
378: }
379: return ret;
380: }
381:
1.52 markus 382: /* Close all channel fd/socket. */
1.127 itojun 383: static void
1.52 markus 384: channel_close_fds(Channel *c)
385: {
1.132 markus 386: channel_close_fd(&c->sock);
387: channel_close_fd(&c->rfd);
388: channel_close_fd(&c->wfd);
389: channel_close_fd(&c->efd);
1.121 markus 390: }
391:
392: /* Free the channel and close its fd/socket. */
393: void
394: channel_free(Channel *c)
395: {
396: char *s;
1.209 avsm 397: u_int i, n;
1.275 djm 398: struct channel_confirm *cc;
1.121 markus 399:
400: for (n = 0, i = 0; i < channels_alloc; i++)
401: if (channels[i])
402: n++;
1.209 avsm 403: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 404: c->remote_name ? c->remote_name : "???", n);
405:
406: s = channel_open_message();
1.194 markus 407: debug3("channel %d: status: %s", c->self, s);
1.321 djm 408: free(s);
1.121 markus 409:
410: if (c->sock != -1)
411: shutdown(c->sock, SHUT_RDWR);
412: channel_close_fds(c);
413: buffer_free(&c->input);
414: buffer_free(&c->output);
415: buffer_free(&c->extended);
1.321 djm 416: free(c->remote_name);
417: c->remote_name = NULL;
418: free(c->path);
419: c->path = NULL;
420: free(c->listening_addr);
421: c->listening_addr = NULL;
1.275 djm 422: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
423: if (cc->abandon_cb != NULL)
424: cc->abandon_cb(c, cc->ctx);
425: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 426: explicit_bzero(cc, sizeof(*cc));
1.321 djm 427: free(cc);
1.275 djm 428: }
1.280 djm 429: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
430: c->filter_cleanup(c->self, c->filter_ctx);
1.121 markus 431: channels[c->self] = NULL;
1.321 djm 432: free(c);
1.121 markus 433: }
434:
435: void
1.126 markus 436: channel_free_all(void)
1.121 markus 437: {
1.209 avsm 438: u_int i;
1.121 markus 439:
1.126 markus 440: for (i = 0; i < channels_alloc; i++)
441: if (channels[i] != NULL)
442: channel_free(channels[i]);
1.131 markus 443: }
444:
1.121 markus 445: /*
446: * Closes the sockets/fds of all channels. This is used to close extra file
447: * descriptors after a fork.
448: */
449: void
1.142 itojun 450: channel_close_all(void)
1.121 markus 451: {
1.209 avsm 452: u_int i;
1.121 markus 453:
454: for (i = 0; i < channels_alloc; i++)
455: if (channels[i] != NULL)
456: channel_close_fds(channels[i]);
457: }
458:
459: /*
1.131 markus 460: * Stop listening to channels.
461: */
462: void
463: channel_stop_listening(void)
464: {
1.209 avsm 465: u_int i;
1.131 markus 466: Channel *c;
467:
468: for (i = 0; i < channels_alloc; i++) {
469: c = channels[i];
470: if (c != NULL) {
471: switch (c->type) {
472: case SSH_CHANNEL_AUTH_SOCKET:
473: case SSH_CHANNEL_PORT_LISTENER:
474: case SSH_CHANNEL_RPORT_LISTENER:
475: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 476: case SSH_CHANNEL_UNIX_LISTENER:
477: case SSH_CHANNEL_RUNIX_LISTENER:
1.132 markus 478: channel_close_fd(&c->sock);
1.131 markus 479: channel_free(c);
480: break;
481: }
482: }
483: }
484: }
485:
486: /*
1.121 markus 487: * Returns true if no channel has too much buffered data, and false if one or
488: * more channel is overfull.
489: */
490: int
1.142 itojun 491: channel_not_very_much_buffered_data(void)
1.121 markus 492: {
493: u_int i;
494: Channel *c;
495:
496: for (i = 0; i < channels_alloc; i++) {
497: c = channels[i];
498: if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
1.136 markus 499: #if 0
500: if (!compat20 &&
501: buffer_len(&c->input) > packet_get_maxsize()) {
1.185 markus 502: debug2("channel %d: big input buffer %d",
1.121 markus 503: c->self, buffer_len(&c->input));
504: return 0;
505: }
1.136 markus 506: #endif
1.121 markus 507: if (buffer_len(&c->output) > packet_get_maxsize()) {
1.191 markus 508: debug2("channel %d: big output buffer %u > %u",
1.136 markus 509: c->self, buffer_len(&c->output),
510: packet_get_maxsize());
1.121 markus 511: return 0;
512: }
513: }
514: }
515: return 1;
516: }
517:
518: /* Returns true if any channel is still open. */
519: int
1.142 itojun 520: channel_still_open(void)
1.121 markus 521: {
1.209 avsm 522: u_int i;
1.121 markus 523: Channel *c;
524:
525: for (i = 0; i < channels_alloc; i++) {
526: c = channels[i];
527: if (c == NULL)
528: continue;
529: switch (c->type) {
530: case SSH_CHANNEL_X11_LISTENER:
531: case SSH_CHANNEL_PORT_LISTENER:
532: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 533: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 534: case SSH_CHANNEL_CLOSED:
535: case SSH_CHANNEL_AUTH_SOCKET:
536: case SSH_CHANNEL_DYNAMIC:
537: case SSH_CHANNEL_CONNECTING:
538: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 539: case SSH_CHANNEL_ABANDONED:
1.336 millert 540: case SSH_CHANNEL_UNIX_LISTENER:
541: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 542: continue;
543: case SSH_CHANNEL_LARVAL:
544: if (!compat20)
545: fatal("cannot happen: SSH_CHANNEL_LARVAL");
546: continue;
547: case SSH_CHANNEL_OPENING:
548: case SSH_CHANNEL_OPEN:
549: case SSH_CHANNEL_X11_OPEN:
1.302 djm 550: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 551: return 1;
552: case SSH_CHANNEL_INPUT_DRAINING:
553: case SSH_CHANNEL_OUTPUT_DRAINING:
554: if (!compat13)
555: fatal("cannot happen: OUT_DRAIN");
556: return 1;
557: default:
558: fatal("channel_still_open: bad channel type %d", c->type);
559: /* NOTREACHED */
560: }
561: }
562: return 0;
563: }
564:
565: /* Returns the id of an open channel suitable for keepaliving */
566: int
1.142 itojun 567: channel_find_open(void)
1.121 markus 568: {
1.209 avsm 569: u_int i;
1.121 markus 570: Channel *c;
571:
572: for (i = 0; i < channels_alloc; i++) {
573: c = channels[i];
1.206 djm 574: if (c == NULL || c->remote_id < 0)
1.121 markus 575: continue;
576: switch (c->type) {
577: case SSH_CHANNEL_CLOSED:
578: case SSH_CHANNEL_DYNAMIC:
579: case SSH_CHANNEL_X11_LISTENER:
580: case SSH_CHANNEL_PORT_LISTENER:
581: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 582: case SSH_CHANNEL_MUX_LISTENER:
583: case SSH_CHANNEL_MUX_CLIENT:
1.121 markus 584: case SSH_CHANNEL_OPENING:
585: case SSH_CHANNEL_CONNECTING:
586: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 587: case SSH_CHANNEL_ABANDONED:
1.336 millert 588: case SSH_CHANNEL_UNIX_LISTENER:
589: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 590: continue;
591: case SSH_CHANNEL_LARVAL:
592: case SSH_CHANNEL_AUTH_SOCKET:
593: case SSH_CHANNEL_OPEN:
594: case SSH_CHANNEL_X11_OPEN:
595: return i;
596: case SSH_CHANNEL_INPUT_DRAINING:
597: case SSH_CHANNEL_OUTPUT_DRAINING:
598: if (!compat13)
599: fatal("cannot happen: OUT_DRAIN");
600: return i;
601: default:
602: fatal("channel_find_open: bad channel type %d", c->type);
603: /* NOTREACHED */
604: }
605: }
606: return -1;
607: }
608:
609:
610: /*
611: * Returns a message describing the currently open forwarded connections,
612: * suitable for sending to the client. The message contains crlf pairs for
613: * newlines.
614: */
615: char *
1.142 itojun 616: channel_open_message(void)
1.121 markus 617: {
618: Buffer buffer;
619: Channel *c;
620: char buf[1024], *cp;
1.209 avsm 621: u_int i;
1.121 markus 622:
623: buffer_init(&buffer);
624: snprintf(buf, sizeof buf, "The following connections are open:\r\n");
625: buffer_append(&buffer, buf, strlen(buf));
626: for (i = 0; i < channels_alloc; i++) {
627: c = channels[i];
628: if (c == NULL)
629: continue;
630: switch (c->type) {
631: case SSH_CHANNEL_X11_LISTENER:
632: case SSH_CHANNEL_PORT_LISTENER:
633: case SSH_CHANNEL_RPORT_LISTENER:
634: case SSH_CHANNEL_CLOSED:
635: case SSH_CHANNEL_AUTH_SOCKET:
636: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 637: case SSH_CHANNEL_ABANDONED:
1.302 djm 638: case SSH_CHANNEL_MUX_CLIENT:
639: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 640: case SSH_CHANNEL_UNIX_LISTENER:
641: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 642: continue;
643: case SSH_CHANNEL_LARVAL:
644: case SSH_CHANNEL_OPENING:
645: case SSH_CHANNEL_CONNECTING:
646: case SSH_CHANNEL_DYNAMIC:
647: case SSH_CHANNEL_OPEN:
648: case SSH_CHANNEL_X11_OPEN:
649: case SSH_CHANNEL_INPUT_DRAINING:
650: case SSH_CHANNEL_OUTPUT_DRAINING:
1.204 djm 651: snprintf(buf, sizeof buf,
1.302 djm 652: " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d cc %d)\r\n",
1.121 markus 653: c->self, c->remote_name,
654: c->type, c->remote_id,
655: c->istate, buffer_len(&c->input),
656: c->ostate, buffer_len(&c->output),
1.302 djm 657: c->rfd, c->wfd, c->ctl_chan);
1.121 markus 658: buffer_append(&buffer, buf, strlen(buf));
659: continue;
660: default:
661: fatal("channel_open_message: bad channel type %d", c->type);
662: /* NOTREACHED */
663: }
664: }
665: buffer_append(&buffer, "\0", 1);
1.337 djm 666: cp = xstrdup((char *)buffer_ptr(&buffer));
1.121 markus 667: buffer_free(&buffer);
668: return cp;
669: }
670:
671: void
672: channel_send_open(int id)
673: {
674: Channel *c = channel_lookup(id);
1.180 deraadt 675:
1.121 markus 676: if (c == NULL) {
1.188 itojun 677: logit("channel_send_open: %d: bad id", id);
1.121 markus 678: return;
679: }
1.184 markus 680: debug2("channel %d: send open", id);
1.121 markus 681: packet_start(SSH2_MSG_CHANNEL_OPEN);
682: packet_put_cstring(c->ctype);
683: packet_put_int(c->self);
684: packet_put_int(c->local_window);
685: packet_put_int(c->local_maxpacket);
686: packet_send();
687: }
688:
689: void
1.184 markus 690: channel_request_start(int id, char *service, int wantconfirm)
1.121 markus 691: {
1.184 markus 692: Channel *c = channel_lookup(id);
1.180 deraadt 693:
1.121 markus 694: if (c == NULL) {
1.188 itojun 695: logit("channel_request_start: %d: unknown channel id", id);
1.121 markus 696: return;
697: }
1.204 djm 698: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.121 markus 699: packet_start(SSH2_MSG_CHANNEL_REQUEST);
700: packet_put_int(c->remote_id);
701: packet_put_cstring(service);
702: packet_put_char(wantconfirm);
703: }
1.241 deraadt 704:
1.121 markus 705: void
1.275 djm 706: channel_register_status_confirm(int id, channel_confirm_cb *cb,
707: channel_confirm_abandon_cb *abandon_cb, void *ctx)
708: {
709: struct channel_confirm *cc;
710: Channel *c;
711:
712: if ((c = channel_lookup(id)) == NULL)
713: fatal("channel_register_expect: %d: bad id", id);
714:
1.327 djm 715: cc = xcalloc(1, sizeof(*cc));
1.275 djm 716: cc->cb = cb;
717: cc->abandon_cb = abandon_cb;
718: cc->ctx = ctx;
719: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
720: }
721:
722: void
1.304 djm 723: channel_register_open_confirm(int id, channel_open_fn *fn, void *ctx)
1.121 markus 724: {
725: Channel *c = channel_lookup(id);
1.180 deraadt 726:
1.121 markus 727: if (c == NULL) {
1.287 stevesk 728: logit("channel_register_open_confirm: %d: bad id", id);
1.121 markus 729: return;
730: }
1.275 djm 731: c->open_confirm = fn;
732: c->open_confirm_ctx = ctx;
1.121 markus 733: }
1.241 deraadt 734:
1.121 markus 735: void
1.225 djm 736: channel_register_cleanup(int id, channel_callback_fn *fn, int do_close)
1.121 markus 737: {
1.229 markus 738: Channel *c = channel_by_id(id);
1.180 deraadt 739:
1.121 markus 740: if (c == NULL) {
1.188 itojun 741: logit("channel_register_cleanup: %d: bad id", id);
1.121 markus 742: return;
743: }
1.131 markus 744: c->detach_user = fn;
1.225 djm 745: c->detach_close = do_close;
1.121 markus 746: }
1.241 deraadt 747:
1.121 markus 748: void
749: channel_cancel_cleanup(int id)
750: {
1.229 markus 751: Channel *c = channel_by_id(id);
1.180 deraadt 752:
1.121 markus 753: if (c == NULL) {
1.188 itojun 754: logit("channel_cancel_cleanup: %d: bad id", id);
1.121 markus 755: return;
1.52 markus 756: }
1.131 markus 757: c->detach_user = NULL;
1.225 djm 758: c->detach_close = 0;
1.121 markus 759: }
1.241 deraadt 760:
1.121 markus 761: void
1.231 reyk 762: channel_register_filter(int id, channel_infilter_fn *ifn,
1.280 djm 763: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 764: {
765: Channel *c = channel_lookup(id);
1.180 deraadt 766:
1.121 markus 767: if (c == NULL) {
1.188 itojun 768: logit("channel_register_filter: %d: bad id", id);
1.121 markus 769: return;
1.52 markus 770: }
1.231 reyk 771: c->input_filter = ifn;
772: c->output_filter = ofn;
1.279 djm 773: c->filter_ctx = ctx;
1.280 djm 774: c->filter_cleanup = cfn;
1.52 markus 775: }
776:
1.49 markus 777: void
1.121 markus 778: channel_set_fds(int id, int rfd, int wfd, int efd,
1.282 dtucker 779: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 780: {
1.121 markus 781: Channel *c = channel_lookup(id);
1.180 deraadt 782:
1.121 markus 783: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
784: fatal("channel_activate for non-larval channel %d.", id);
1.282 dtucker 785: channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 786: c->type = SSH_CHANNEL_OPEN;
1.168 markus 787: c->local_window = c->local_window_max = window_max;
1.121 markus 788: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
789: packet_put_int(c->remote_id);
790: packet_put_int(c->local_window);
791: packet_send();
1.1 deraadt 792: }
793:
1.27 markus 794: /*
1.41 markus 795: * 'channel_pre*' are called just before select() to add any bits relevant to
796: * channels in the select bitmasks.
797: */
798: /*
799: * 'channel_post*': perform any appropriate operations for channels which
800: * have events pending.
1.27 markus 801: */
1.237 deraadt 802: typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset);
1.41 markus 803: chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
804: chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
805:
1.259 stevesk 806: /* ARGSUSED */
1.127 itojun 807: static void
1.237 deraadt 808: channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 809: {
810: FD_SET(c->sock, readset);
811: }
812:
1.259 stevesk 813: /* ARGSUSED */
1.127 itojun 814: static void
1.237 deraadt 815: channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 816: {
817: debug3("channel %d: waiting for connection", c->self);
818: FD_SET(c->sock, writeset);
819: }
820:
1.127 itojun 821: static void
1.237 deraadt 822: channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 823: {
824: if (buffer_len(&c->input) < packet_get_maxsize())
825: FD_SET(c->sock, readset);
826: if (buffer_len(&c->output) > 0)
827: FD_SET(c->sock, writeset);
828: }
1.1 deraadt 829:
1.127 itojun 830: static void
1.237 deraadt 831: channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 832: {
1.157 markus 833: u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
1.41 markus 834:
1.44 markus 835: if (c->istate == CHAN_INPUT_OPEN &&
1.157 markus 836: limit > 0 &&
1.250 djm 837: buffer_len(&c->input) < limit &&
838: buffer_check_alloc(&c->input, CHAN_RBUF))
1.44 markus 839: FD_SET(c->rfd, readset);
840: if (c->ostate == CHAN_OUTPUT_OPEN ||
841: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
842: if (buffer_len(&c->output) > 0) {
843: FD_SET(c->wfd, writeset);
844: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 845: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.223 djm 846: debug2("channel %d: obuf_empty delayed efd %d/(%d)",
847: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 848: else
849: chan_obuf_empty(c);
1.44 markus 850: }
851: }
852: /** XXX check close conditions, too */
1.277 markus 853: if (compat20 && c->efd != -1 &&
854: !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 855: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
856: buffer_len(&c->extended) > 0)
857: FD_SET(c->efd, writeset);
1.306 djm 858: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
859: (c->extended_usage == CHAN_EXTENDED_READ ||
860: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 861: buffer_len(&c->extended) < c->remote_window)
862: FD_SET(c->efd, readset);
863: }
1.204 djm 864: /* XXX: What about efd? races? */
1.44 markus 865: }
866:
1.259 stevesk 867: /* ARGSUSED */
1.127 itojun 868: static void
1.237 deraadt 869: channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 870: {
871: if (buffer_len(&c->input) == 0) {
872: packet_start(SSH_MSG_CHANNEL_CLOSE);
873: packet_put_int(c->remote_id);
874: packet_send();
875: c->type = SSH_CHANNEL_CLOSED;
1.194 markus 876: debug2("channel %d: closing after input drain.", c->self);
1.41 markus 877: }
878: }
879:
1.259 stevesk 880: /* ARGSUSED */
1.127 itojun 881: static void
1.237 deraadt 882: channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 883: {
884: if (buffer_len(&c->output) == 0)
1.113 markus 885: chan_mark_dead(c);
1.49 markus 886: else
1.41 markus 887: FD_SET(c->sock, writeset);
888: }
889:
890: /*
891: * This is a special state for X11 authentication spoofing. An opened X11
892: * connection (when authentication spoofing is being done) remains in this
893: * state until the first packet has been completely read. The authentication
894: * data in that packet is then substituted by the real data if it matches the
895: * fake data, and the channel is put into normal mode.
1.51 markus 896: * XXX All this happens at the client side.
1.121 markus 897: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 898: */
1.127 itojun 899: static int
1.121 markus 900: x11_open_helper(Buffer *b)
1.1 deraadt 901: {
1.77 markus 902: u_char *ucp;
903: u_int proto_len, data_len;
1.25 markus 904:
1.41 markus 905: /* Check if the fixed size part of the packet is in buffer. */
1.121 markus 906: if (buffer_len(b) < 12)
1.41 markus 907: return 0;
908:
909: /* Parse the lengths of variable-length fields. */
1.155 stevesk 910: ucp = buffer_ptr(b);
1.41 markus 911: if (ucp[0] == 0x42) { /* Byte order MSB first. */
912: proto_len = 256 * ucp[6] + ucp[7];
913: data_len = 256 * ucp[8] + ucp[9];
914: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
915: proto_len = ucp[6] + 256 * ucp[7];
916: data_len = ucp[8] + 256 * ucp[9];
917: } else {
1.194 markus 918: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 919: ucp[0]);
1.41 markus 920: return -1;
921: }
922:
923: /* Check if the whole packet is in buffer. */
1.121 markus 924: if (buffer_len(b) <
1.41 markus 925: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
926: return 0;
927:
928: /* Check if authentication protocol matches. */
929: if (proto_len != strlen(x11_saved_proto) ||
930: memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
1.194 markus 931: debug2("X11 connection uses different authentication protocol.");
1.41 markus 932: return -1;
933: }
934: /* Check if authentication data matches our fake data. */
935: if (data_len != x11_fake_data_len ||
1.308 djm 936: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.41 markus 937: x11_fake_data, x11_fake_data_len) != 0) {
1.194 markus 938: debug2("X11 auth data does not match fake data.");
1.41 markus 939: return -1;
940: }
941: /* Check fake data length */
942: if (x11_fake_data_len != x11_saved_data_len) {
943: error("X11 fake_data_len %d != saved_data_len %d",
944: x11_fake_data_len, x11_saved_data_len);
945: return -1;
946: }
947: /*
948: * Received authentication protocol and data match
949: * our fake data. Substitute the fake data with real
950: * data.
951: */
952: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
953: x11_saved_data, x11_saved_data_len);
954: return 1;
955: }
956:
1.127 itojun 957: static void
1.237 deraadt 958: channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 959: {
1.121 markus 960: int ret = x11_open_helper(&c->output);
1.180 deraadt 961:
1.41 markus 962: if (ret == 1) {
963: /* Start normal processing for the channel. */
964: c->type = SSH_CHANNEL_OPEN;
1.47 markus 965: channel_pre_open_13(c, readset, writeset);
1.41 markus 966: } else if (ret == -1) {
967: /*
968: * We have received an X11 connection that has bad
969: * authentication information.
970: */
1.188 itojun 971: logit("X11 connection rejected because of wrong authentication.");
1.41 markus 972: buffer_clear(&c->input);
973: buffer_clear(&c->output);
1.132 markus 974: channel_close_fd(&c->sock);
1.41 markus 975: c->sock = -1;
976: c->type = SSH_CHANNEL_CLOSED;
977: packet_start(SSH_MSG_CHANNEL_CLOSE);
978: packet_put_int(c->remote_id);
979: packet_send();
980: }
981: }
1.25 markus 982:
1.127 itojun 983: static void
1.237 deraadt 984: channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 985: {
1.121 markus 986: int ret = x11_open_helper(&c->output);
1.133 markus 987:
988: /* c->force_drain = 1; */
989:
1.41 markus 990: if (ret == 1) {
991: c->type = SSH_CHANNEL_OPEN;
1.157 markus 992: channel_pre_open(c, readset, writeset);
1.41 markus 993: } else if (ret == -1) {
1.188 itojun 994: logit("X11 connection rejected because of wrong authentication.");
1.194 markus 995: debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
1.156 markus 996: chan_read_failed(c);
997: buffer_clear(&c->input);
998: chan_ibuf_empty(c);
999: buffer_clear(&c->output);
1000: /* for proto v1, the peer will send an IEOF */
1001: if (compat20)
1002: chan_write_failed(c);
1003: else
1004: c->type = SSH_CHANNEL_OPEN;
1.194 markus 1005: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1006: }
1007: }
1.25 markus 1008:
1.302 djm 1009: static void
1010: channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1011: {
1.304 djm 1012: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.302 djm 1013: buffer_check_alloc(&c->input, CHAN_RBUF))
1014: FD_SET(c->rfd, readset);
1015: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1016: /* clear buffer immediately (discard any partial packet) */
1017: buffer_clear(&c->input);
1018: chan_ibuf_empty(c);
1019: /* Start output drain. XXX just kill chan? */
1020: chan_rcvd_oclose(c);
1021: }
1022: if (c->ostate == CHAN_OUTPUT_OPEN ||
1023: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1024: if (buffer_len(&c->output) > 0)
1025: FD_SET(c->wfd, writeset);
1026: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1027: chan_obuf_empty(c);
1028: }
1029: }
1030:
1.104 markus 1031: /* try to decode a socks4 header */
1.259 stevesk 1032: /* ARGSUSED */
1.127 itojun 1033: static int
1.237 deraadt 1034: channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
1.103 markus 1035: {
1.181 markus 1036: char *p, *host;
1.292 djm 1037: u_int len, have, i, found, need;
1.148 deraadt 1038: char username[256];
1.103 markus 1039: struct {
1040: u_int8_t version;
1041: u_int8_t command;
1042: u_int16_t dest_port;
1.104 markus 1043: struct in_addr dest_addr;
1.103 markus 1044: } s4_req, s4_rsp;
1045:
1.104 markus 1046: debug2("channel %d: decode socks4", c->self);
1.109 markus 1047:
1048: have = buffer_len(&c->input);
1049: len = sizeof(s4_req);
1050: if (have < len)
1051: return 0;
1.337 djm 1052: p = (char *)buffer_ptr(&c->input);
1.292 djm 1053:
1054: need = 1;
1055: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1056: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1057: debug2("channel %d: socks4a request", c->self);
1058: /* ... and needs an extra string (the hostname) */
1059: need = 2;
1060: }
1061: /* Check for terminating NUL on the string(s) */
1.109 markus 1062: for (found = 0, i = len; i < have; i++) {
1063: if (p[i] == '\0') {
1.292 djm 1064: found++;
1065: if (found == need)
1066: break;
1.109 markus 1067: }
1068: if (i > 1024) {
1069: /* the peer is probably sending garbage */
1070: debug("channel %d: decode socks4: too long",
1071: c->self);
1072: return -1;
1073: }
1074: }
1.292 djm 1075: if (found < need)
1.109 markus 1076: return 0;
1.103 markus 1077: buffer_get(&c->input, (char *)&s4_req.version, 1);
1078: buffer_get(&c->input, (char *)&s4_req.command, 1);
1079: buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
1.104 markus 1080: buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
1.109 markus 1081: have = buffer_len(&c->input);
1.337 djm 1082: p = (char *)buffer_ptr(&c->input);
1.331 djm 1083: if (memchr(p, '\0', have) == NULL)
1084: fatal("channel %d: decode socks4: user not nul terminated",
1085: c->self);
1.103 markus 1086: len = strlen(p);
1.106 markus 1087: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.292 djm 1088: len++; /* trailing '\0' */
1.103 markus 1089: if (len > have)
1.104 markus 1090: fatal("channel %d: decode socks4: len %d > have %d",
1.103 markus 1091: c->self, len, have);
1092: strlcpy(username, p, sizeof(username));
1093: buffer_consume(&c->input, len);
1094:
1.321 djm 1095: free(c->path);
1096: c->path = NULL;
1.292 djm 1097: if (need == 1) { /* SOCKS4: one string */
1098: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1099: c->path = xstrdup(host);
1.292 djm 1100: } else { /* SOCKS4A: two strings */
1101: have = buffer_len(&c->input);
1.337 djm 1102: p = (char *)buffer_ptr(&c->input);
1.292 djm 1103: len = strlen(p);
1104: debug2("channel %d: decode socks4a: host %s/%d",
1105: c->self, p, len);
1106: len++; /* trailing '\0' */
1107: if (len > have)
1108: fatal("channel %d: decode socks4a: len %d > have %d",
1109: c->self, len, have);
1.293 djm 1110: if (len > NI_MAXHOST) {
1.292 djm 1111: error("channel %d: hostname \"%.100s\" too long",
1112: c->self, p);
1113: return -1;
1114: }
1.293 djm 1115: c->path = xstrdup(p);
1.292 djm 1116: buffer_consume(&c->input, len);
1117: }
1.103 markus 1118: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1119:
1.194 markus 1120: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1121: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1122:
1.104 markus 1123: if (s4_req.command != 1) {
1.292 djm 1124: debug("channel %d: cannot handle: %s cn %d",
1125: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1126: return -1;
1.103 markus 1127: }
1.104 markus 1128: s4_rsp.version = 0; /* vn: 0 for reply */
1129: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1130: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1131: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.246 deraadt 1132: buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp));
1.104 markus 1133: return 1;
1134: }
1135:
1.193 markus 1136: /* try to decode a socks5 header */
1137: #define SSH_SOCKS5_AUTHDONE 0x1000
1138: #define SSH_SOCKS5_NOAUTH 0x00
1139: #define SSH_SOCKS5_IPV4 0x01
1140: #define SSH_SOCKS5_DOMAIN 0x03
1141: #define SSH_SOCKS5_IPV6 0x04
1142: #define SSH_SOCKS5_CONNECT 0x01
1143: #define SSH_SOCKS5_SUCCESS 0x00
1144:
1.259 stevesk 1145: /* ARGSUSED */
1.193 markus 1146: static int
1.237 deraadt 1147: channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
1.193 markus 1148: {
1149: struct {
1150: u_int8_t version;
1151: u_int8_t command;
1152: u_int8_t reserved;
1153: u_int8_t atyp;
1154: } s5_req, s5_rsp;
1155: u_int16_t dest_port;
1.324 djm 1156: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1157: u_char *p;
1.252 djm 1158: u_int have, need, i, found, nmethods, addrlen, af;
1.193 markus 1159:
1160: debug2("channel %d: decode socks5", c->self);
1161: p = buffer_ptr(&c->input);
1162: if (p[0] != 0x05)
1163: return -1;
1164: have = buffer_len(&c->input);
1165: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1166: /* format: ver | nmethods | methods */
1.198 djm 1167: if (have < 2)
1.193 markus 1168: return 0;
1169: nmethods = p[1];
1170: if (have < nmethods + 2)
1171: return 0;
1172: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1173: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1174: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1175: found = 1;
1176: break;
1177: }
1178: }
1179: if (!found) {
1180: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1181: c->self);
1182: return -1;
1183: }
1184: buffer_consume(&c->input, nmethods + 2);
1185: buffer_put_char(&c->output, 0x05); /* version */
1186: buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */
1187: FD_SET(c->sock, writeset);
1188: c->flags |= SSH_SOCKS5_AUTHDONE;
1189: debug2("channel %d: socks5 auth done", c->self);
1190: return 0; /* need more */
1191: }
1192: debug2("channel %d: socks5 post auth", c->self);
1193: if (have < sizeof(s5_req)+1)
1194: return 0; /* need more */
1.247 deraadt 1195: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1196: if (s5_req.version != 0x05 ||
1197: s5_req.command != SSH_SOCKS5_CONNECT ||
1198: s5_req.reserved != 0x00) {
1.194 markus 1199: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1200: return -1;
1201: }
1.213 deraadt 1202: switch (s5_req.atyp){
1.193 markus 1203: case SSH_SOCKS5_IPV4:
1204: addrlen = 4;
1205: af = AF_INET;
1206: break;
1207: case SSH_SOCKS5_DOMAIN:
1208: addrlen = p[sizeof(s5_req)];
1209: af = -1;
1210: break;
1211: case SSH_SOCKS5_IPV6:
1212: addrlen = 16;
1213: af = AF_INET6;
1214: break;
1215: default:
1.194 markus 1216: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1217: return -1;
1218: }
1.252 djm 1219: need = sizeof(s5_req) + addrlen + 2;
1220: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1221: need++;
1222: if (have < need)
1.193 markus 1223: return 0;
1224: buffer_consume(&c->input, sizeof(s5_req));
1225: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1226: buffer_consume(&c->input, 1); /* host string length */
1.324 djm 1227: buffer_get(&c->input, &dest_addr, addrlen);
1.193 markus 1228: buffer_get(&c->input, (char *)&dest_port, 2);
1229: dest_addr[addrlen] = '\0';
1.321 djm 1230: free(c->path);
1231: c->path = NULL;
1.293 djm 1232: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1233: if (addrlen >= NI_MAXHOST) {
1.293 djm 1234: error("channel %d: dynamic request: socks5 hostname "
1235: "\"%.100s\" too long", c->self, dest_addr);
1236: return -1;
1237: }
1238: c->path = xstrdup(dest_addr);
1239: } else {
1240: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1241: return -1;
1242: c->path = xstrdup(ntop);
1243: }
1.193 markus 1244: c->host_port = ntohs(dest_port);
1.198 djm 1245:
1.194 markus 1246: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1247: c->self, c->path, c->host_port, s5_req.command);
1248:
1249: s5_rsp.version = 0x05;
1250: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1251: s5_rsp.reserved = 0; /* ignored */
1252: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1253: dest_port = 0; /* ignored */
1254:
1.246 deraadt 1255: buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
1.325 djm 1256: buffer_put_int(&c->output, ntohl(INADDR_ANY)); /* bind address */
1.246 deraadt 1257: buffer_append(&c->output, &dest_port, sizeof(dest_port));
1.193 markus 1258: return 1;
1.301 dtucker 1259: }
1260:
1261: Channel *
1.302 djm 1262: channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect,
1263: int in, int out)
1.301 dtucker 1264: {
1265: Channel *c;
1266:
1267: debug("channel_connect_stdio_fwd %s:%d", host_to_connect,
1268: port_to_connect);
1269:
1270: c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out,
1271: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1272: 0, "stdio-forward", /*nonblock*/0);
1273:
1274: c->path = xstrdup(host_to_connect);
1275: c->host_port = port_to_connect;
1276: c->listening_port = 0;
1277: c->force_drain = 1;
1278:
1279: channel_register_fds(c, in, out, -1, 0, 1, 0);
1280: port_open_helper(c, "direct-tcpip");
1281:
1282: return c;
1.193 markus 1283: }
1284:
1.104 markus 1285: /* dynamic port forwarding */
1.127 itojun 1286: static void
1.237 deraadt 1287: channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset)
1.104 markus 1288: {
1289: u_char *p;
1.217 djm 1290: u_int have;
1291: int ret;
1.103 markus 1292:
1.104 markus 1293: have = buffer_len(&c->input);
1294: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.105 markus 1295: /* buffer_dump(&c->input); */
1.104 markus 1296: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1297: if (have < 3) {
1.104 markus 1298: /* need more */
1299: FD_SET(c->sock, readset);
1300: return;
1301: }
1302: /* try to guess the protocol */
1303: p = buffer_ptr(&c->input);
1304: switch (p[0]) {
1305: case 0x04:
1306: ret = channel_decode_socks4(c, readset, writeset);
1.193 markus 1307: break;
1308: case 0x05:
1309: ret = channel_decode_socks5(c, readset, writeset);
1.104 markus 1310: break;
1311: default:
1312: ret = -1;
1313: break;
1314: }
1315: if (ret < 0) {
1.113 markus 1316: chan_mark_dead(c);
1.104 markus 1317: } else if (ret == 0) {
1318: debug2("channel %d: pre_dynamic: need more", c->self);
1319: /* need more */
1320: FD_SET(c->sock, readset);
1321: } else {
1322: /* switch to the next state */
1323: c->type = SSH_CHANNEL_OPENING;
1324: port_open_helper(c, "direct-tcpip");
1325: }
1.103 markus 1326: }
1327:
1.41 markus 1328: /* This is our fake X11 server socket. */
1.259 stevesk 1329: /* ARGSUSED */
1.127 itojun 1330: static void
1.237 deraadt 1331: channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1332: {
1.113 markus 1333: Channel *nc;
1.285 djm 1334: struct sockaddr_storage addr;
1.320 markus 1335: int newsock, oerrno;
1.41 markus 1336: socklen_t addrlen;
1.85 markus 1337: char buf[16384], *remote_ipaddr;
1.51 markus 1338: int remote_port;
1.25 markus 1339:
1.41 markus 1340: if (FD_ISSET(c->sock, readset)) {
1341: debug("X11 connection requested.");
1342: addrlen = sizeof(addr);
1.285 djm 1343: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.149 markus 1344: if (c->single_connection) {
1.320 markus 1345: oerrno = errno;
1.194 markus 1346: debug2("single_connection: closing X11 listener.");
1.149 markus 1347: channel_close_fd(&c->sock);
1348: chan_mark_dead(c);
1.320 markus 1349: errno = oerrno;
1.149 markus 1350: }
1.41 markus 1351: if (newsock < 0) {
1.320 markus 1352: if (errno != EINTR && errno != EWOULDBLOCK &&
1353: errno != ECONNABORTED)
1354: error("accept: %.100s", strerror(errno));
1.317 djm 1355: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1356: c->notbefore = monotime() + 1;
1.41 markus 1357: return;
1358: }
1.162 stevesk 1359: set_nodelay(newsock);
1.85 markus 1360: remote_ipaddr = get_peer_ipaddr(newsock);
1.51 markus 1361: remote_port = get_peer_port(newsock);
1.41 markus 1362: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1.85 markus 1363: remote_ipaddr, remote_port);
1.51 markus 1364:
1.113 markus 1365: nc = channel_new("accepted x11 socket",
1.51 markus 1366: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1.190 markus 1367: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1.51 markus 1368: if (compat20) {
1369: packet_start(SSH2_MSG_CHANNEL_OPEN);
1370: packet_put_cstring("x11");
1.113 markus 1371: packet_put_int(nc->self);
1.149 markus 1372: packet_put_int(nc->local_window_max);
1373: packet_put_int(nc->local_maxpacket);
1.85 markus 1374: /* originator ipaddr and port */
1375: packet_put_cstring(remote_ipaddr);
1.57 markus 1376: if (datafellows & SSH_BUG_X11FWD) {
1.194 markus 1377: debug2("ssh2 x11 bug compat mode");
1.57 markus 1378: } else {
1379: packet_put_int(remote_port);
1380: }
1.51 markus 1381: packet_send();
1382: } else {
1383: packet_start(SSH_SMSG_X11_OPEN);
1.113 markus 1384: packet_put_int(nc->self);
1.121 markus 1385: if (packet_get_protocol_flags() &
1386: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.125 markus 1387: packet_put_cstring(buf);
1.51 markus 1388: packet_send();
1389: }
1.321 djm 1390: free(remote_ipaddr);
1.41 markus 1391: }
1392: }
1.25 markus 1393:
1.127 itojun 1394: static void
1.103 markus 1395: port_open_helper(Channel *c, char *rtype)
1396: {
1397: char buf[1024];
1.328 djm 1398: char *local_ipaddr = get_local_ipaddr(c->sock);
1.330 djm 1399: int local_port = c->sock == -1 ? 65536 : get_sock_port(c->sock, 1);
1.103 markus 1400: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1401: int remote_port = get_peer_port(c->sock);
1.303 djm 1402:
1403: if (remote_port == -1) {
1404: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1405: free(remote_ipaddr);
1.303 djm 1406: remote_ipaddr = xstrdup("127.0.0.1");
1407: remote_port = 65535;
1408: }
1.103 markus 1409:
1410: snprintf(buf, sizeof buf,
1411: "%s: listening port %d for %.100s port %d, "
1.328 djm 1412: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1413: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1414: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1415:
1.321 djm 1416: free(c->remote_name);
1.103 markus 1417: c->remote_name = xstrdup(buf);
1418:
1419: if (compat20) {
1420: packet_start(SSH2_MSG_CHANNEL_OPEN);
1421: packet_put_cstring(rtype);
1422: packet_put_int(c->self);
1423: packet_put_int(c->local_window_max);
1424: packet_put_int(c->local_maxpacket);
1.336 millert 1425: if (strcmp(rtype, "direct-tcpip") == 0) {
1.103 markus 1426: /* target host, port */
1427: packet_put_cstring(c->path);
1428: packet_put_int(c->host_port);
1.336 millert 1429: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1430: /* target path */
1431: packet_put_cstring(c->path);
1432: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1433: /* listen path */
1434: packet_put_cstring(c->path);
1.103 markus 1435: } else {
1436: /* listen address, port */
1437: packet_put_cstring(c->path);
1.328 djm 1438: packet_put_int(local_port);
1.103 markus 1439: }
1.336 millert 1440: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1441: /* reserved for future owner/mode info */
1442: packet_put_cstring("");
1443: } else {
1444: /* originator host and port */
1445: packet_put_cstring(remote_ipaddr);
1446: packet_put_int((u_int)remote_port);
1447: }
1.103 markus 1448: packet_send();
1449: } else {
1450: packet_start(SSH_MSG_PORT_OPEN);
1451: packet_put_int(c->self);
1452: packet_put_cstring(c->path);
1453: packet_put_int(c->host_port);
1.121 markus 1454: if (packet_get_protocol_flags() &
1455: SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
1.103 markus 1456: packet_put_cstring(c->remote_name);
1457: packet_send();
1458: }
1.321 djm 1459: free(remote_ipaddr);
1.328 djm 1460: free(local_ipaddr);
1.103 markus 1461: }
1462:
1.226 djm 1463: static void
1464: channel_set_reuseaddr(int fd)
1465: {
1466: int on = 1;
1467:
1468: /*
1469: * Set socket options.
1470: * Allow local port reuse in TIME_WAIT.
1471: */
1472: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
1473: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
1474: }
1475:
1.41 markus 1476: /*
1477: * This socket is listening for connections to a forwarded TCP/IP port.
1478: */
1.259 stevesk 1479: /* ARGSUSED */
1.127 itojun 1480: static void
1.237 deraadt 1481: channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1482: {
1.103 markus 1483: Channel *nc;
1.285 djm 1484: struct sockaddr_storage addr;
1.113 markus 1485: int newsock, nextstate;
1.41 markus 1486: socklen_t addrlen;
1.103 markus 1487: char *rtype;
1.73 markus 1488:
1.41 markus 1489: if (FD_ISSET(c->sock, readset)) {
1490: debug("Connection to port %d forwarding "
1491: "to %.100s port %d requested.",
1492: c->listening_port, c->path, c->host_port);
1.103 markus 1493:
1.137 markus 1494: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1495: nextstate = SSH_CHANNEL_OPENING;
1496: rtype = "forwarded-tcpip";
1.336 millert 1497: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1498: nextstate = SSH_CHANNEL_OPENING;
1499: rtype = "forwarded-streamlocal@openssh.com";
1500: } else if (c->host_port == PORT_STREAMLOCAL) {
1501: nextstate = SSH_CHANNEL_OPENING;
1502: rtype = "direct-streamlocal@openssh.com";
1503: } else if (c->host_port == 0) {
1504: nextstate = SSH_CHANNEL_DYNAMIC;
1505: rtype = "dynamic-tcpip";
1.137 markus 1506: } else {
1.336 millert 1507: nextstate = SSH_CHANNEL_OPENING;
1508: rtype = "direct-tcpip";
1.137 markus 1509: }
1.103 markus 1510:
1.41 markus 1511: addrlen = sizeof(addr);
1.285 djm 1512: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1513: if (newsock < 0) {
1.320 markus 1514: if (errno != EINTR && errno != EWOULDBLOCK &&
1515: errno != ECONNABORTED)
1516: error("accept: %.100s", strerror(errno));
1.317 djm 1517: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1518: c->notbefore = monotime() + 1;
1.41 markus 1519: return;
1520: }
1.336 millert 1521: if (c->host_port != PORT_STREAMLOCAL)
1522: set_nodelay(newsock);
1.190 markus 1523: nc = channel_new(rtype, nextstate, newsock, newsock, -1,
1524: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1.103 markus 1525: nc->listening_port = c->listening_port;
1526: nc->host_port = c->host_port;
1.293 djm 1527: if (c->path != NULL)
1528: nc->path = xstrdup(c->path);
1.103 markus 1529:
1.299 markus 1530: if (nextstate != SSH_CHANNEL_DYNAMIC)
1.103 markus 1531: port_open_helper(nc, rtype);
1.41 markus 1532: }
1533: }
1.25 markus 1534:
1.41 markus 1535: /*
1536: * This is the authentication agent socket listening for connections from
1537: * clients.
1538: */
1.259 stevesk 1539: /* ARGSUSED */
1.127 itojun 1540: static void
1.237 deraadt 1541: channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1542: {
1.113 markus 1543: Channel *nc;
1544: int newsock;
1.285 djm 1545: struct sockaddr_storage addr;
1.41 markus 1546: socklen_t addrlen;
1.25 markus 1547:
1.41 markus 1548: if (FD_ISSET(c->sock, readset)) {
1549: addrlen = sizeof(addr);
1.285 djm 1550: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.41 markus 1551: if (newsock < 0) {
1.317 djm 1552: error("accept from auth socket: %.100s",
1553: strerror(errno));
1554: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1555: c->notbefore = monotime() + 1;
1.41 markus 1556: return;
1557: }
1.113 markus 1558: nc = channel_new("accepted auth socket",
1.73 markus 1559: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1560: c->local_window_max, c->local_maxpacket,
1.190 markus 1561: 0, "accepted auth socket", 1);
1.73 markus 1562: if (compat20) {
1563: packet_start(SSH2_MSG_CHANNEL_OPEN);
1564: packet_put_cstring("auth-agent@openssh.com");
1.113 markus 1565: packet_put_int(nc->self);
1.73 markus 1566: packet_put_int(c->local_window_max);
1567: packet_put_int(c->local_maxpacket);
1568: } else {
1569: packet_start(SSH_SMSG_AGENT_OPEN);
1.113 markus 1570: packet_put_int(nc->self);
1.73 markus 1571: }
1.41 markus 1572: packet_send();
1573: }
1574: }
1.25 markus 1575:
1.259 stevesk 1576: /* ARGSUSED */
1.127 itojun 1577: static void
1.237 deraadt 1578: channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset)
1.75 markus 1579: {
1.276 djm 1580: int err = 0, sock;
1.129 stevesk 1581: socklen_t sz = sizeof(err);
1.114 markus 1582:
1.75 markus 1583: if (FD_ISSET(c->sock, writeset)) {
1.170 stevesk 1584: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
1.114 markus 1585: err = errno;
1586: error("getsockopt SO_ERROR failed");
1587: }
1588: if (err == 0) {
1.276 djm 1589: debug("channel %d: connected to %s port %d",
1590: c->self, c->connect_ctx.host, c->connect_ctx.port);
1591: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1592: c->type = SSH_CHANNEL_OPEN;
1593: if (compat20) {
1594: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1595: packet_put_int(c->remote_id);
1596: packet_put_int(c->self);
1597: packet_put_int(c->local_window);
1598: packet_put_int(c->local_maxpacket);
1599: } else {
1600: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1601: packet_put_int(c->remote_id);
1602: packet_put_int(c->self);
1603: }
1.75 markus 1604: } else {
1.276 djm 1605: debug("channel %d: connection failed: %s",
1.114 markus 1606: c->self, strerror(err));
1.276 djm 1607: /* Try next address, if any */
1608: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1609: close(c->sock);
1610: c->sock = c->rfd = c->wfd = sock;
1611: channel_max_fd = channel_find_maxfd();
1612: return;
1613: }
1614: /* Exhausted all addresses */
1615: error("connect_to %.100s port %d: failed.",
1616: c->connect_ctx.host, c->connect_ctx.port);
1617: channel_connect_ctx_free(&c->connect_ctx);
1.114 markus 1618: if (compat20) {
1619: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1620: packet_put_int(c->remote_id);
1621: packet_put_int(SSH2_OPEN_CONNECT_FAILED);
1622: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1623: packet_put_cstring(strerror(err));
1624: packet_put_cstring("");
1625: }
1.75 markus 1626: } else {
1.114 markus 1627: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1628: packet_put_int(c->remote_id);
1.75 markus 1629: }
1.114 markus 1630: chan_mark_dead(c);
1.75 markus 1631: }
1.114 markus 1632: packet_send();
1.75 markus 1633: }
1634: }
1635:
1.259 stevesk 1636: /* ARGSUSED */
1.127 itojun 1637: static int
1.237 deraadt 1638: channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1639: {
1.214 markus 1640: char buf[CHAN_RBUF];
1.41 markus 1641: int len;
1.25 markus 1642:
1.118 markus 1643: if (c->rfd != -1 &&
1.41 markus 1644: FD_ISSET(c->rfd, readset)) {
1645: len = read(c->rfd, buf, sizeof(buf));
1.53 markus 1646: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1647: return 1;
1.41 markus 1648: if (len <= 0) {
1.194 markus 1649: debug2("channel %d: read<=0 rfd %d len %d",
1.41 markus 1650: c->self, c->rfd, len);
1.104 markus 1651: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1652: debug2("channel %d: not open", c->self);
1.113 markus 1653: chan_mark_dead(c);
1.103 markus 1654: return -1;
1.104 markus 1655: } else if (compat13) {
1.158 markus 1656: buffer_clear(&c->output);
1.41 markus 1657: c->type = SSH_CHANNEL_INPUT_DRAINING;
1.194 markus 1658: debug2("channel %d: input draining.", c->self);
1.25 markus 1659: } else {
1.41 markus 1660: chan_read_failed(c);
1.25 markus 1661: }
1.41 markus 1662: return -1;
1663: }
1.143 deraadt 1664: if (c->input_filter != NULL) {
1.66 markus 1665: if (c->input_filter(c, buf, len) == -1) {
1.194 markus 1666: debug2("channel %d: filter stops", c->self);
1.65 markus 1667: chan_read_failed(c);
1668: }
1.228 reyk 1669: } else if (c->datagram) {
1670: buffer_put_string(&c->input, buf, len);
1.65 markus 1671: } else {
1672: buffer_append(&c->input, buf, len);
1673: }
1.41 markus 1674: }
1675: return 1;
1676: }
1.241 deraadt 1677:
1.259 stevesk 1678: /* ARGSUSED */
1.127 itojun 1679: static int
1.237 deraadt 1680: channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1681: {
1.95 markus 1682: struct termios tio;
1.231 reyk 1683: u_char *data = NULL, *buf;
1.309 djm 1684: u_int dlen, olen = 0;
1.41 markus 1685: int len;
1.25 markus 1686:
1.41 markus 1687: /* Send buffered output data to the socket. */
1.118 markus 1688: if (c->wfd != -1 &&
1.41 markus 1689: FD_ISSET(c->wfd, writeset) &&
1690: buffer_len(&c->output) > 0) {
1.309 djm 1691: olen = buffer_len(&c->output);
1.231 reyk 1692: if (c->output_filter != NULL) {
1693: if ((buf = c->output_filter(c, &data, &dlen)) == NULL) {
1694: debug2("channel %d: filter stops", c->self);
1.232 reyk 1695: if (c->type != SSH_CHANNEL_OPEN)
1696: chan_mark_dead(c);
1697: else
1698: chan_write_failed(c);
1699: return -1;
1.231 reyk 1700: }
1701: } else if (c->datagram) {
1702: buf = data = buffer_get_string(&c->output, &dlen);
1703: } else {
1704: buf = data = buffer_ptr(&c->output);
1705: dlen = buffer_len(&c->output);
1706: }
1707:
1.228 reyk 1708: if (c->datagram) {
1709: /* ignore truncated writes, datagrams might get lost */
1.231 reyk 1710: len = write(c->wfd, buf, dlen);
1.321 djm 1711: free(data);
1.228 reyk 1712: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1713: return 1;
1714: if (len <= 0) {
1715: if (c->type != SSH_CHANNEL_OPEN)
1716: chan_mark_dead(c);
1717: else
1718: chan_write_failed(c);
1719: return -1;
1720: }
1.309 djm 1721: goto out;
1.228 reyk 1722: }
1.231 reyk 1723:
1724: len = write(c->wfd, buf, dlen);
1.53 markus 1725: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1726: return 1;
1.41 markus 1727: if (len <= 0) {
1.104 markus 1728: if (c->type != SSH_CHANNEL_OPEN) {
1.194 markus 1729: debug2("channel %d: not open", c->self);
1.113 markus 1730: chan_mark_dead(c);
1.104 markus 1731: return -1;
1732: } else if (compat13) {
1.158 markus 1733: buffer_clear(&c->output);
1.194 markus 1734: debug2("channel %d: input draining.", c->self);
1.41 markus 1735: c->type = SSH_CHANNEL_INPUT_DRAINING;
1736: } else {
1737: chan_write_failed(c);
1738: }
1739: return -1;
1.91 markus 1740: }
1.231 reyk 1741: if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') {
1.91 markus 1742: if (tcgetattr(c->wfd, &tio) == 0 &&
1743: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
1744: /*
1745: * Simulate echo to reduce the impact of
1.96 markus 1746: * traffic analysis. We need to match the
1.95 markus 1747: * size of a SSH2_MSG_CHANNEL_DATA message
1.231 reyk 1748: * (4 byte channel id + buf)
1.91 markus 1749: */
1.95 markus 1750: packet_send_ignore(4 + len);
1.91 markus 1751: packet_send();
1752: }
1.25 markus 1753: }
1.41 markus 1754: buffer_consume(&c->output, len);
1.44 markus 1755: }
1.309 djm 1756: out:
1757: if (compat20 && olen > 0)
1758: c->local_consumed += olen - buffer_len(&c->output);
1.44 markus 1759: return 1;
1760: }
1.241 deraadt 1761:
1.127 itojun 1762: static int
1.237 deraadt 1763: channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset)
1.44 markus 1764: {
1.214 markus 1765: char buf[CHAN_RBUF];
1.44 markus 1766: int len;
1767:
1.45 markus 1768: /** XXX handle drain efd, too */
1.44 markus 1769: if (c->efd != -1) {
1770: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1771: FD_ISSET(c->efd, writeset) &&
1772: buffer_len(&c->extended) > 0) {
1773: len = write(c->efd, buffer_ptr(&c->extended),
1774: buffer_len(&c->extended));
1.70 markus 1775: debug2("channel %d: written %d to efd %d",
1.44 markus 1776: c->self, len, c->efd);
1.93 markus 1777: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1778: return 1;
1779: if (len <= 0) {
1780: debug2("channel %d: closing write-efd %d",
1781: c->self, c->efd);
1.132 markus 1782: channel_close_fd(&c->efd);
1.93 markus 1783: } else {
1.44 markus 1784: buffer_consume(&c->extended, len);
1785: c->local_consumed += len;
1786: }
1.306 djm 1787: } else if (c->efd != -1 &&
1788: (c->extended_usage == CHAN_EXTENDED_READ ||
1789: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.44 markus 1790: FD_ISSET(c->efd, readset)) {
1791: len = read(c->efd, buf, sizeof(buf));
1.70 markus 1792: debug2("channel %d: read %d from efd %d",
1.148 deraadt 1793: c->self, len, c->efd);
1.93 markus 1794: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1795: return 1;
1796: if (len <= 0) {
1797: debug2("channel %d: closing read-efd %d",
1.45 markus 1798: c->self, c->efd);
1.132 markus 1799: channel_close_fd(&c->efd);
1.93 markus 1800: } else {
1.306 djm 1801: if (c->extended_usage == CHAN_EXTENDED_IGNORE) {
1802: debug3("channel %d: discard efd",
1803: c->self);
1804: } else
1805: buffer_append(&c->extended, buf, len);
1.93 markus 1806: }
1.44 markus 1807: }
1808: }
1809: return 1;
1810: }
1.241 deraadt 1811:
1.259 stevesk 1812: /* ARGSUSED */
1.127 itojun 1813: static int
1.93 markus 1814: channel_check_window(Channel *c)
1.44 markus 1815: {
1.104 markus 1816: if (c->type == SSH_CHANNEL_OPEN &&
1817: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 1818: ((c->local_window_max - c->local_window >
1.269 markus 1819: c->local_maxpacket*3) ||
1820: c->local_window < c->local_window_max/2) &&
1.44 markus 1821: c->local_consumed > 0) {
1822: packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
1823: packet_put_int(c->remote_id);
1824: packet_put_int(c->local_consumed);
1825: packet_send();
1.70 markus 1826: debug2("channel %d: window %d sent adjust %d",
1.44 markus 1827: c->self, c->local_window,
1828: c->local_consumed);
1829: c->local_window += c->local_consumed;
1830: c->local_consumed = 0;
1.1 deraadt 1831: }
1.41 markus 1832: return 1;
1.1 deraadt 1833: }
1834:
1.127 itojun 1835: static void
1.237 deraadt 1836: channel_post_open(Channel *c, fd_set *readset, fd_set *writeset)
1.41 markus 1837: {
1838: channel_handle_rfd(c, readset, writeset);
1839: channel_handle_wfd(c, readset, writeset);
1.157 markus 1840: if (!compat20)
1.137 markus 1841: return;
1.44 markus 1842: channel_handle_efd(c, readset, writeset);
1.93 markus 1843: channel_check_window(c);
1.44 markus 1844: }
1845:
1.302 djm 1846: static u_int
1847: read_mux(Channel *c, u_int need)
1848: {
1849: char buf[CHAN_RBUF];
1850: int len;
1851: u_int rlen;
1852:
1853: if (buffer_len(&c->input) < need) {
1854: rlen = need - buffer_len(&c->input);
1855: len = read(c->rfd, buf, MIN(rlen, CHAN_RBUF));
1856: if (len <= 0) {
1857: if (errno != EINTR && errno != EAGAIN) {
1858: debug2("channel %d: ctl read<=0 rfd %d len %d",
1859: c->self, c->rfd, len);
1860: chan_read_failed(c);
1861: return 0;
1862: }
1863: } else
1864: buffer_append(&c->input, buf, len);
1865: }
1866: return buffer_len(&c->input);
1867: }
1868:
1869: static void
1870: channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset)
1871: {
1872: u_int need;
1873: ssize_t len;
1874:
1875: if (!compat20)
1876: fatal("%s: entered with !compat20", __func__);
1877:
1.304 djm 1878: if (c->rfd != -1 && !c->mux_pause && FD_ISSET(c->rfd, readset) &&
1.302 djm 1879: (c->istate == CHAN_INPUT_OPEN ||
1880: c->istate == CHAN_INPUT_WAIT_DRAIN)) {
1881: /*
1882: * Don't not read past the precise end of packets to
1883: * avoid disrupting fd passing.
1884: */
1885: if (read_mux(c, 4) < 4) /* read header */
1886: return;
1887: need = get_u32(buffer_ptr(&c->input));
1888: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1889: if (need > CHANNEL_MUX_MAX_PACKET) {
1890: debug2("channel %d: packet too big %u > %u",
1891: c->self, CHANNEL_MUX_MAX_PACKET, need);
1892: chan_rcvd_oclose(c);
1893: return;
1894: }
1895: if (read_mux(c, need + 4) < need + 4) /* read body */
1896: return;
1897: if (c->mux_rcb(c) != 0) {
1898: debug("channel %d: mux_rcb failed", c->self);
1899: chan_mark_dead(c);
1900: return;
1901: }
1902: }
1903:
1904: if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) &&
1905: buffer_len(&c->output) > 0) {
1906: len = write(c->wfd, buffer_ptr(&c->output),
1907: buffer_len(&c->output));
1908: if (len < 0 && (errno == EINTR || errno == EAGAIN))
1909: return;
1910: if (len <= 0) {
1911: chan_mark_dead(c);
1912: return;
1913: }
1914: buffer_consume(&c->output, len);
1915: }
1916: }
1917:
1918: static void
1919: channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset)
1920: {
1921: Channel *nc;
1922: struct sockaddr_storage addr;
1923: socklen_t addrlen;
1924: int newsock;
1925: uid_t euid;
1926: gid_t egid;
1927:
1928: if (!FD_ISSET(c->sock, readset))
1929: return;
1930:
1931: debug("multiplexing control connection");
1932:
1933: /*
1934: * Accept connection on control socket
1935: */
1936: memset(&addr, 0, sizeof(addr));
1937: addrlen = sizeof(addr);
1938: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
1939: &addrlen)) == -1) {
1940: error("%s accept: %s", __func__, strerror(errno));
1.317 djm 1941: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 1942: c->notbefore = monotime() + 1;
1.302 djm 1943: return;
1944: }
1945:
1946: if (getpeereid(newsock, &euid, &egid) < 0) {
1947: error("%s getpeereid failed: %s", __func__,
1948: strerror(errno));
1949: close(newsock);
1950: return;
1951: }
1952: if ((euid != 0) && (getuid() != euid)) {
1953: error("multiplex uid mismatch: peer euid %u != uid %u",
1954: (u_int)euid, (u_int)getuid());
1955: close(newsock);
1956: return;
1957: }
1958: nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT,
1959: newsock, newsock, -1, c->local_window_max,
1960: c->local_maxpacket, 0, "mux-control", 1);
1961: nc->mux_rcb = c->mux_rcb;
1962: debug3("%s: new mux channel %d fd %d", __func__,
1963: nc->self, nc->sock);
1964: /* establish state */
1965: nc->mux_rcb(nc);
1966: /* mux state transitions must not elicit protocol messages */
1967: nc->flags |= CHAN_LOCAL;
1968: }
1969:
1.259 stevesk 1970: /* ARGSUSED */
1.127 itojun 1971: static void
1.237 deraadt 1972: channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset)
1.1 deraadt 1973: {
1.41 markus 1974: int len;
1.180 deraadt 1975:
1.41 markus 1976: /* Send buffered output data to the socket. */
1977: if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
1978: len = write(c->sock, buffer_ptr(&c->output),
1979: buffer_len(&c->output));
1980: if (len <= 0)
1.158 markus 1981: buffer_clear(&c->output);
1.41 markus 1982: else
1983: buffer_consume(&c->output, len);
1984: }
1985: }
1.25 markus 1986:
1.127 itojun 1987: static void
1.44 markus 1988: channel_handler_init_20(void)
1989: {
1.157 markus 1990: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 1991: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.44 markus 1992: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
1.73 markus 1993: channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
1.336 millert 1994: channel_pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
1995: channel_pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
1.51 markus 1996: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
1.73 markus 1997: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 1998: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 1999: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.302 djm 2000: channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2001: channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
1.44 markus 2002:
1.157 markus 2003: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.44 markus 2004: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
1.73 markus 2005: channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
1.336 millert 2006: channel_post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2007: channel_post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
1.51 markus 2008: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
1.73 markus 2009: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.75 markus 2010: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2011: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.302 djm 2012: channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2013: channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.44 markus 2014: }
2015:
1.127 itojun 2016: static void
1.41 markus 2017: channel_handler_init_13(void)
2018: {
2019: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
2020: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
2021: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2022: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2023: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2024: channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
2025: channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
1.75 markus 2026: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2027: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 2028:
1.157 markus 2029: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.41 markus 2030: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2031: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2032: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2033: channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
1.75 markus 2034: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2035: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2036: }
1.25 markus 2037:
1.127 itojun 2038: static void
1.41 markus 2039: channel_handler_init_15(void)
2040: {
1.157 markus 2041: channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
1.51 markus 2042: channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
1.41 markus 2043: channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2044: channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2045: channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
1.75 markus 2046: channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
1.103 markus 2047: channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.25 markus 2048:
1.41 markus 2049: channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2050: channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2051: channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
1.157 markus 2052: channel_post[SSH_CHANNEL_OPEN] = &channel_post_open;
1.75 markus 2053: channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
1.157 markus 2054: channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.41 markus 2055: }
1.27 markus 2056:
1.127 itojun 2057: static void
1.41 markus 2058: channel_handler_init(void)
2059: {
2060: int i;
1.180 deraadt 2061:
1.148 deraadt 2062: for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
1.41 markus 2063: channel_pre[i] = NULL;
2064: channel_post[i] = NULL;
2065: }
1.44 markus 2066: if (compat20)
2067: channel_handler_init_20();
2068: else if (compat13)
1.41 markus 2069: channel_handler_init_13();
2070: else
2071: channel_handler_init_15();
2072: }
1.25 markus 2073:
1.140 markus 2074: /* gc dead channels */
2075: static void
2076: channel_garbage_collect(Channel *c)
2077: {
2078: if (c == NULL)
2079: return;
2080: if (c->detach_user != NULL) {
1.225 djm 2081: if (!chan_is_dead(c, c->detach_close))
1.140 markus 2082: return;
1.194 markus 2083: debug2("channel %d: gc: notify user", c->self);
1.140 markus 2084: c->detach_user(c->self, NULL);
2085: /* if we still have a callback */
2086: if (c->detach_user != NULL)
2087: return;
1.194 markus 2088: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2089: }
2090: if (!chan_is_dead(c, 1))
2091: return;
1.194 markus 2092: debug2("channel %d: garbage collecting", c->self);
1.140 markus 2093: channel_free(c);
2094: }
2095:
1.127 itojun 2096: static void
1.317 djm 2097: channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset,
2098: time_t *unpause_secs)
1.41 markus 2099: {
2100: static int did_init = 0;
1.299 markus 2101: u_int i, oalloc;
1.41 markus 2102: Channel *c;
1.317 djm 2103: time_t now;
1.25 markus 2104:
1.41 markus 2105: if (!did_init) {
2106: channel_handler_init();
2107: did_init = 1;
2108: }
1.322 dtucker 2109: now = monotime();
1.317 djm 2110: if (unpause_secs != NULL)
2111: *unpause_secs = 0;
1.299 markus 2112: for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
1.113 markus 2113: c = channels[i];
2114: if (c == NULL)
1.41 markus 2115: continue;
1.299 markus 2116: if (c->delayed) {
2117: if (ftab == channel_pre)
2118: c->delayed = 0;
2119: else
2120: continue;
2121: }
1.317 djm 2122: if (ftab[c->type] != NULL) {
2123: /*
2124: * Run handlers that are not paused.
2125: */
2126: if (c->notbefore <= now)
2127: (*ftab[c->type])(c, readset, writeset);
2128: else if (unpause_secs != NULL) {
2129: /*
2130: * Collect the time that the earliest
2131: * channel comes off pause.
2132: */
2133: debug3("%s: chan %d: skip for %d more seconds",
2134: __func__, c->self,
2135: (int)(c->notbefore - now));
2136: if (*unpause_secs == 0 ||
2137: (c->notbefore - now) < *unpause_secs)
2138: *unpause_secs = c->notbefore - now;
2139: }
2140: }
1.140 markus 2141: channel_garbage_collect(c);
1.1 deraadt 2142: }
1.317 djm 2143: if (unpause_secs != NULL && *unpause_secs != 0)
2144: debug3("%s: first channel unpauses in %d seconds",
2145: __func__, (int)*unpause_secs);
1.1 deraadt 2146: }
2147:
1.121 markus 2148: /*
2149: * Allocate/update select bitmasks and add any bits relevant to channels in
2150: * select bitmasks.
2151: */
1.49 markus 2152: void
1.100 markus 2153: channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
1.318 djm 2154: u_int *nallocp, time_t *minwait_secs, int rekeying)
1.41 markus 2155: {
1.243 djm 2156: u_int n, sz, nfdset;
1.84 markus 2157:
2158: n = MAX(*maxfdp, channel_max_fd);
2159:
1.243 djm 2160: nfdset = howmany(n+1, NFDBITS);
2161: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2162: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2163: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2164: sz = nfdset * sizeof(fd_mask);
2165:
1.132 markus 2166: /* perhaps check sz < nalloc/2 and shrink? */
2167: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2168: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2169: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2170: *nallocp = sz;
1.84 markus 2171: }
1.132 markus 2172: *maxfdp = n;
1.84 markus 2173: memset(*readsetp, 0, sz);
2174: memset(*writesetp, 0, sz);
2175:
1.100 markus 2176: if (!rekeying)
1.317 djm 2177: channel_handler(channel_pre, *readsetp, *writesetp,
2178: minwait_secs);
1.41 markus 2179: }
2180:
1.121 markus 2181: /*
2182: * After select, perform any appropriate operations for channels which have
2183: * events pending.
2184: */
1.49 markus 2185: void
1.237 deraadt 2186: channel_after_select(fd_set *readset, fd_set *writeset)
1.41 markus 2187: {
1.317 djm 2188: channel_handler(channel_post, readset, writeset, NULL);
1.41 markus 2189: }
2190:
1.121 markus 2191:
1.84 markus 2192: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2193: void
1.142 itojun 2194: channel_output_poll(void)
1.1 deraadt 2195: {
1.41 markus 2196: Channel *c;
1.209 avsm 2197: u_int i, len;
1.1 deraadt 2198:
1.25 markus 2199: for (i = 0; i < channels_alloc; i++) {
1.113 markus 2200: c = channels[i];
2201: if (c == NULL)
2202: continue;
1.37 markus 2203:
1.121 markus 2204: /*
2205: * We are only interested in channels that can have buffered
2206: * incoming data.
2207: */
1.37 markus 2208: if (compat13) {
1.41 markus 2209: if (c->type != SSH_CHANNEL_OPEN &&
2210: c->type != SSH_CHANNEL_INPUT_DRAINING)
1.37 markus 2211: continue;
2212: } else {
1.41 markus 2213: if (c->type != SSH_CHANNEL_OPEN)
1.37 markus 2214: continue;
2215: }
1.46 markus 2216: if (compat20 &&
2217: (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2218: /* XXX is this true? */
1.140 markus 2219: debug3("channel %d: will not send data after close", c->self);
1.44 markus 2220: continue;
2221: }
1.25 markus 2222:
2223: /* Get the amount of buffered data for this channel. */
1.93 markus 2224: if ((c->istate == CHAN_INPUT_OPEN ||
2225: c->istate == CHAN_INPUT_WAIT_DRAIN) &&
2226: (len = buffer_len(&c->input)) > 0) {
1.228 reyk 2227: if (c->datagram) {
2228: if (len > 0) {
2229: u_char *data;
2230: u_int dlen;
2231:
2232: data = buffer_get_string(&c->input,
2233: &dlen);
1.309 djm 2234: if (dlen > c->remote_window ||
2235: dlen > c->remote_maxpacket) {
2236: debug("channel %d: datagram "
2237: "too big for channel",
2238: c->self);
1.321 djm 2239: free(data);
1.309 djm 2240: continue;
2241: }
1.228 reyk 2242: packet_start(SSH2_MSG_CHANNEL_DATA);
2243: packet_put_int(c->remote_id);
2244: packet_put_string(data, dlen);
2245: packet_send();
1.345 djm 2246: c->remote_window -= dlen;
1.321 djm 2247: free(data);
1.228 reyk 2248: }
2249: continue;
2250: }
1.121 markus 2251: /*
2252: * Send some data for the other side over the secure
2253: * connection.
2254: */
1.44 markus 2255: if (compat20) {
2256: if (len > c->remote_window)
2257: len = c->remote_window;
2258: if (len > c->remote_maxpacket)
2259: len = c->remote_maxpacket;
1.25 markus 2260: } else {
1.44 markus 2261: if (packet_is_interactive()) {
2262: if (len > 1024)
2263: len = 512;
2264: } else {
2265: /* Keep the packets at reasonable size. */
2266: if (len > packet_get_maxsize()/2)
2267: len = packet_get_maxsize()/2;
2268: }
1.25 markus 2269: }
1.41 markus 2270: if (len > 0) {
1.44 markus 2271: packet_start(compat20 ?
2272: SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1.41 markus 2273: packet_put_int(c->remote_id);
2274: packet_put_string(buffer_ptr(&c->input), len);
2275: packet_send();
2276: buffer_consume(&c->input, len);
2277: c->remote_window -= len;
2278: }
2279: } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1.25 markus 2280: if (compat13)
2281: fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1.27 markus 2282: /*
2283: * input-buffer is empty and read-socket shutdown:
1.172 markus 2284: * tell peer, that we will not send more data: send IEOF.
2285: * hack for extended data: delay EOF if EFD still in use.
1.27 markus 2286: */
1.172 markus 2287: if (CHANNEL_EFD_INPUT_ACTIVE(c))
1.223 djm 2288: debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2289: c->self, c->efd, buffer_len(&c->extended));
1.172 markus 2290: else
2291: chan_ibuf_empty(c);
1.25 markus 2292: }
1.44 markus 2293: /* Send extended data, i.e. stderr */
2294: if (compat20 &&
1.172 markus 2295: !(c->flags & CHAN_EOF_SENT) &&
1.44 markus 2296: c->remote_window > 0 &&
2297: (len = buffer_len(&c->extended)) > 0 &&
2298: c->extended_usage == CHAN_EXTENDED_READ) {
1.178 markus 2299: debug2("channel %d: rwin %u elen %u euse %d",
1.93 markus 2300: c->self, c->remote_window, buffer_len(&c->extended),
2301: c->extended_usage);
1.44 markus 2302: if (len > c->remote_window)
2303: len = c->remote_window;
2304: if (len > c->remote_maxpacket)
2305: len = c->remote_maxpacket;
2306: packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
2307: packet_put_int(c->remote_id);
2308: packet_put_int(SSH2_EXTENDED_DATA_STDERR);
2309: packet_put_string(buffer_ptr(&c->extended), len);
2310: packet_send();
2311: buffer_consume(&c->extended, len);
2312: c->remote_window -= len;
1.93 markus 2313: debug2("channel %d: sent ext data %d", c->self, len);
1.44 markus 2314: }
1.25 markus 2315: }
1.1 deraadt 2316: }
2317:
1.121 markus 2318:
2319: /* -- protocol input */
1.249 djm 2320:
2321: /* ARGSUSED */
1.339 markus 2322: int
1.154 markus 2323: channel_input_data(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2324: {
1.37 markus 2325: int id;
1.332 djm 2326: const u_char *data;
1.309 djm 2327: u_int data_len, win_len;
1.41 markus 2328: Channel *c;
1.25 markus 2329:
2330: /* Get the channel number and verify it. */
1.37 markus 2331: id = packet_get_int();
1.41 markus 2332: c = channel_lookup(id);
2333: if (c == NULL)
1.37 markus 2334: packet_disconnect("Received data for nonexistent channel %d.", id);
1.25 markus 2335:
2336: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2337: if (c->type != SSH_CHANNEL_OPEN &&
2338: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2339: return 0;
1.37 markus 2340:
1.25 markus 2341: /* Get the data. */
1.274 markus 2342: data = packet_get_string_ptr(&data_len);
1.309 djm 2343: win_len = data_len;
2344: if (c->datagram)
2345: win_len += 4; /* string length header */
1.200 markus 2346:
2347: /*
2348: * Ignore data for protocol > 1.3 if output end is no longer open.
2349: * For protocol 2 the sending side is reducing its window as it sends
2350: * data, so we must 'fake' consumption of the data in order to ensure
2351: * that window updates are sent back. Otherwise the connection might
2352: * deadlock.
2353: */
2354: if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) {
2355: if (compat20) {
1.309 djm 2356: c->local_window -= win_len;
2357: c->local_consumed += win_len;
1.200 markus 2358: }
1.339 markus 2359: return 0;
1.200 markus 2360: }
1.41 markus 2361:
1.143 deraadt 2362: if (compat20) {
1.309 djm 2363: if (win_len > c->local_maxpacket) {
1.188 itojun 2364: logit("channel %d: rcvd big packet %d, maxpack %d",
1.309 djm 2365: c->self, win_len, c->local_maxpacket);
1.44 markus 2366: }
1.309 djm 2367: if (win_len > c->local_window) {
1.188 itojun 2368: logit("channel %d: rcvd too much data %d, win %d",
1.309 djm 2369: c->self, win_len, c->local_window);
1.339 markus 2370: return 0;
1.44 markus 2371: }
1.309 djm 2372: c->local_window -= win_len;
1.44 markus 2373: }
1.228 reyk 2374: if (c->datagram)
2375: buffer_put_string(&c->output, data, data_len);
2376: else
2377: buffer_append(&c->output, data, data_len);
1.274 markus 2378: packet_check_eom();
1.339 markus 2379: return 0;
1.1 deraadt 2380: }
1.121 markus 2381:
1.249 djm 2382: /* ARGSUSED */
1.339 markus 2383: int
1.154 markus 2384: channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
1.44 markus 2385: {
2386: int id;
2387: char *data;
1.177 markus 2388: u_int data_len, tcode;
1.44 markus 2389: Channel *c;
2390:
2391: /* Get the channel number and verify it. */
2392: id = packet_get_int();
2393: c = channel_lookup(id);
2394:
2395: if (c == NULL)
2396: packet_disconnect("Received extended_data for bad channel %d.", id);
2397: if (c->type != SSH_CHANNEL_OPEN) {
1.188 itojun 2398: logit("channel %d: ext data for non open", id);
1.339 markus 2399: return 0;
1.172 markus 2400: }
2401: if (c->flags & CHAN_EOF_RCVD) {
2402: if (datafellows & SSH_BUG_EXTEOF)
2403: debug("channel %d: accepting ext data after eof", id);
2404: else
2405: packet_disconnect("Received extended_data after EOF "
2406: "on channel %d.", id);
1.44 markus 2407: }
2408: tcode = packet_get_int();
2409: if (c->efd == -1 ||
2410: c->extended_usage != CHAN_EXTENDED_WRITE ||
2411: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 2412: logit("channel %d: bad ext data", c->self);
1.339 markus 2413: return 0;
1.44 markus 2414: }
2415: data = packet_get_string(&data_len);
1.152 markus 2416: packet_check_eom();
1.44 markus 2417: if (data_len > c->local_window) {
1.188 itojun 2418: logit("channel %d: rcvd too much extended_data %d, win %d",
1.44 markus 2419: c->self, data_len, c->local_window);
1.321 djm 2420: free(data);
1.339 markus 2421: return 0;
1.44 markus 2422: }
1.70 markus 2423: debug2("channel %d: rcvd ext data %d", c->self, data_len);
1.44 markus 2424: c->local_window -= data_len;
2425: buffer_append(&c->extended, data, data_len);
1.321 djm 2426: free(data);
1.339 markus 2427: return 0;
1.44 markus 2428: }
2429:
1.249 djm 2430: /* ARGSUSED */
1.339 markus 2431: int
1.154 markus 2432: channel_input_ieof(int type, u_int32_t seq, void *ctxt)
1.41 markus 2433: {
2434: int id;
2435: Channel *c;
2436:
2437: id = packet_get_int();
1.152 markus 2438: packet_check_eom();
1.41 markus 2439: c = channel_lookup(id);
2440: if (c == NULL)
2441: packet_disconnect("Received ieof for nonexistent channel %d.", id);
2442: chan_rcvd_ieof(c);
1.133 markus 2443:
2444: /* XXX force input close */
1.156 markus 2445: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 2446: debug("channel %d: FORCE input drain", c->self);
2447: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.161 markus 2448: if (buffer_len(&c->input) == 0)
2449: chan_ibuf_empty(c);
1.133 markus 2450: }
1.339 markus 2451: return 0;
1.41 markus 2452: }
1.1 deraadt 2453:
1.249 djm 2454: /* ARGSUSED */
1.339 markus 2455: int
1.154 markus 2456: channel_input_close(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2457: {
1.41 markus 2458: int id;
2459: Channel *c;
1.1 deraadt 2460:
1.41 markus 2461: id = packet_get_int();
1.152 markus 2462: packet_check_eom();
1.41 markus 2463: c = channel_lookup(id);
2464: if (c == NULL)
2465: packet_disconnect("Received close for nonexistent channel %d.", id);
1.27 markus 2466:
2467: /*
2468: * Send a confirmation that we have closed the channel and no more
2469: * data is coming for it.
2470: */
1.25 markus 2471: packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1.41 markus 2472: packet_put_int(c->remote_id);
1.25 markus 2473: packet_send();
2474:
1.27 markus 2475: /*
2476: * If the channel is in closed state, we have sent a close request,
2477: * and the other side will eventually respond with a confirmation.
2478: * Thus, we cannot free the channel here, because then there would be
2479: * no-one to receive the confirmation. The channel gets freed when
2480: * the confirmation arrives.
2481: */
1.41 markus 2482: if (c->type != SSH_CHANNEL_CLOSED) {
1.27 markus 2483: /*
2484: * Not a closed channel - mark it as draining, which will
2485: * cause it to be freed later.
2486: */
1.158 markus 2487: buffer_clear(&c->input);
1.41 markus 2488: c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1.25 markus 2489: }
1.339 markus 2490: return 0;
1.1 deraadt 2491: }
2492:
1.41 markus 2493: /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1.249 djm 2494: /* ARGSUSED */
1.339 markus 2495: int
1.154 markus 2496: channel_input_oclose(int type, u_int32_t seq, void *ctxt)
1.41 markus 2497: {
2498: int id = packet_get_int();
2499: Channel *c = channel_lookup(id);
1.151 markus 2500:
1.152 markus 2501: packet_check_eom();
1.41 markus 2502: if (c == NULL)
2503: packet_disconnect("Received oclose for nonexistent channel %d.", id);
2504: chan_rcvd_oclose(c);
1.339 markus 2505: return 0;
1.41 markus 2506: }
1.1 deraadt 2507:
1.249 djm 2508: /* ARGSUSED */
1.339 markus 2509: int
1.154 markus 2510: channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2511: {
1.41 markus 2512: int id = packet_get_int();
2513: Channel *c = channel_lookup(id);
1.1 deraadt 2514:
1.152 markus 2515: packet_check_eom();
1.41 markus 2516: if (c == NULL)
2517: packet_disconnect("Received close confirmation for "
2518: "out-of-range channel %d.", id);
1.323 dtucker 2519: if (c->type != SSH_CHANNEL_CLOSED && c->type != SSH_CHANNEL_ABANDONED)
1.41 markus 2520: packet_disconnect("Received close confirmation for "
2521: "non-closed channel %d (type %d).", id, c->type);
1.113 markus 2522: channel_free(c);
1.339 markus 2523: return 0;
1.1 deraadt 2524: }
2525:
1.249 djm 2526: /* ARGSUSED */
1.339 markus 2527: int
1.154 markus 2528: channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2529: {
1.41 markus 2530: int id, remote_id;
2531: Channel *c;
1.1 deraadt 2532:
1.41 markus 2533: id = packet_get_int();
2534: c = channel_lookup(id);
1.25 markus 2535:
1.41 markus 2536: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2537: packet_disconnect("Received open confirmation for "
2538: "non-opening channel %d.", id);
2539: remote_id = packet_get_int();
1.27 markus 2540: /* Record the remote channel number and mark that the channel is now open. */
1.41 markus 2541: c->remote_id = remote_id;
2542: c->type = SSH_CHANNEL_OPEN;
1.44 markus 2543:
2544: if (compat20) {
2545: c->remote_window = packet_get_int();
2546: c->remote_maxpacket = packet_get_int();
1.275 djm 2547: if (c->open_confirm) {
1.70 markus 2548: debug2("callback start");
1.304 djm 2549: c->open_confirm(c->self, 1, c->open_confirm_ctx);
1.70 markus 2550: debug2("callback done");
1.44 markus 2551: }
1.194 markus 2552: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
1.44 markus 2553: c->remote_window, c->remote_maxpacket);
2554: }
1.152 markus 2555: packet_check_eom();
1.339 markus 2556: return 0;
1.1 deraadt 2557: }
2558:
1.127 itojun 2559: static char *
1.114 markus 2560: reason2txt(int reason)
2561: {
1.143 deraadt 2562: switch (reason) {
1.114 markus 2563: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
2564: return "administratively prohibited";
2565: case SSH2_OPEN_CONNECT_FAILED:
2566: return "connect failed";
2567: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
2568: return "unknown channel type";
2569: case SSH2_OPEN_RESOURCE_SHORTAGE:
2570: return "resource shortage";
2571: }
1.117 stevesk 2572: return "unknown reason";
1.114 markus 2573: }
2574:
1.249 djm 2575: /* ARGSUSED */
1.339 markus 2576: int
1.154 markus 2577: channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2578: {
1.86 markus 2579: int id, reason;
2580: char *msg = NULL, *lang = NULL;
1.41 markus 2581: Channel *c;
2582:
2583: id = packet_get_int();
2584: c = channel_lookup(id);
1.25 markus 2585:
1.41 markus 2586: if (c==NULL || c->type != SSH_CHANNEL_OPENING)
2587: packet_disconnect("Received open failure for "
2588: "non-opening channel %d.", id);
1.44 markus 2589: if (compat20) {
1.86 markus 2590: reason = packet_get_int();
1.110 markus 2591: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.86 markus 2592: msg = packet_get_string(NULL);
2593: lang = packet_get_string(NULL);
2594: }
1.188 itojun 2595: logit("channel %d: open failed: %s%s%s", id,
1.114 markus 2596: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
1.321 djm 2597: free(msg);
2598: free(lang);
1.304 djm 2599: if (c->open_confirm) {
2600: debug2("callback start");
2601: c->open_confirm(c->self, 0, c->open_confirm_ctx);
2602: debug2("callback done");
2603: }
1.44 markus 2604: }
1.152 markus 2605: packet_check_eom();
1.291 djm 2606: /* Schedule the channel for cleanup/deletion. */
2607: chan_mark_dead(c);
1.339 markus 2608: return 0;
1.44 markus 2609: }
2610:
1.249 djm 2611: /* ARGSUSED */
1.339 markus 2612: int
1.154 markus 2613: channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
1.121 markus 2614: {
2615: Channel *c;
1.178 markus 2616: int id;
1.346 ! djm 2617: u_int adjust, tmp;
1.121 markus 2618:
2619: if (!compat20)
1.339 markus 2620: return 0;
1.121 markus 2621:
2622: /* Get the channel number and verify it. */
2623: id = packet_get_int();
2624: c = channel_lookup(id);
1.1 deraadt 2625:
1.229 markus 2626: if (c == NULL) {
2627: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 2628: return 0;
1.121 markus 2629: }
2630: adjust = packet_get_int();
1.152 markus 2631: packet_check_eom();
1.178 markus 2632: debug2("channel %d: rcvd adjust %u", id, adjust);
1.346 ! djm 2633: if ((tmp = c->remote_window + adjust) < c->remote_window)
! 2634: fatal("channel %d: adjust %u overflows remote window %u",
! 2635: id, adjust, c->remote_window);
! 2636: c->remote_window = tmp;
1.339 markus 2637: return 0;
1.121 markus 2638: }
1.1 deraadt 2639:
1.249 djm 2640: /* ARGSUSED */
1.339 markus 2641: int
1.154 markus 2642: channel_input_port_open(int type, u_int32_t seq, void *ctxt)
1.1 deraadt 2643: {
1.121 markus 2644: Channel *c = NULL;
2645: u_short host_port;
2646: char *host, *originator_string;
1.276 djm 2647: int remote_id;
1.121 markus 2648:
2649: remote_id = packet_get_int();
2650: host = packet_get_string(NULL);
2651: host_port = packet_get_int();
1.25 markus 2652:
1.121 markus 2653: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
2654: originator_string = packet_get_string(NULL);
2655: } else {
2656: originator_string = xstrdup("unknown (remote did not supply name)");
2657: }
1.152 markus 2658: packet_check_eom();
1.336 millert 2659: c = channel_connect_to_port(host, host_port,
1.276 djm 2660: "connected socket", originator_string);
1.321 djm 2661: free(originator_string);
2662: free(host);
1.121 markus 2663: if (c == NULL) {
2664: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2665: packet_put_int(remote_id);
2666: packet_send();
1.276 djm 2667: } else
2668: c->remote_id = remote_id;
1.339 markus 2669: return 0;
1.1 deraadt 2670: }
2671:
1.275 djm 2672: /* ARGSUSED */
1.339 markus 2673: int
1.275 djm 2674: channel_input_status_confirm(int type, u_int32_t seq, void *ctxt)
2675: {
2676: Channel *c;
2677: struct channel_confirm *cc;
1.289 markus 2678: int id;
1.275 djm 2679:
2680: /* Reset keepalive timeout */
1.296 andreas 2681: packet_set_alive_timeouts(0);
1.275 djm 2682:
1.289 markus 2683: id = packet_get_int();
1.275 djm 2684: packet_check_eom();
2685:
1.289 markus 2686: debug2("channel_input_status_confirm: type %d id %d", type, id);
1.275 djm 2687:
1.289 markus 2688: if ((c = channel_lookup(id)) == NULL) {
2689: logit("channel_input_status_confirm: %d: unknown", id);
1.339 markus 2690: return 0;
1.275 djm 2691: }
2692: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 2693: return 0;
1.275 djm 2694: cc->cb(type, c, cc->ctx);
2695: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.329 tedu 2696: explicit_bzero(cc, sizeof(*cc));
1.321 djm 2697: free(cc);
1.339 markus 2698: return 0;
1.275 djm 2699: }
1.121 markus 2700:
2701: /* -- tcp forwarding */
1.135 markus 2702:
2703: void
2704: channel_set_af(int af)
2705: {
2706: IPv4or6 = af;
2707: }
1.121 markus 2708:
1.312 djm 2709:
2710: /*
2711: * Determine whether or not a port forward listens to loopback, the
2712: * specified address or wildcard. On the client, a specified bind
2713: * address will always override gateway_ports. On the server, a
2714: * gateway_ports of 1 (``yes'') will override the client's specification
2715: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
2716: * will bind to whatever address the client asked for.
2717: *
2718: * Special-case listen_addrs are:
2719: *
2720: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2721: * "" (empty string), "*" -> wildcard v4/v6
2722: * "localhost" -> loopback v4/v6
1.334 djm 2723: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 2724: */
2725: static const char *
2726: channel_fwd_bind_addr(const char *listen_addr, int *wildcardp,
1.336 millert 2727: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 2728: {
2729: const char *addr = NULL;
2730: int wildcard = 0;
2731:
2732: if (listen_addr == NULL) {
2733: /* No address specified: default to gateway_ports setting */
1.336 millert 2734: if (fwd_opts->gateway_ports)
1.312 djm 2735: wildcard = 1;
1.336 millert 2736: } else if (fwd_opts->gateway_ports || is_client) {
1.312 djm 2737: if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
2738: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
2739: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 2740: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 2741: wildcard = 1;
1.326 djm 2742: /*
2743: * Notify client if they requested a specific listen
2744: * address and it was overridden.
2745: */
2746: if (*listen_addr != '\0' &&
2747: strcmp(listen_addr, "0.0.0.0") != 0 &&
2748: strcmp(listen_addr, "*") != 0) {
2749: packet_send_debug("Forwarding listen address "
2750: "\"%s\" overridden by server "
2751: "GatewayPorts", listen_addr);
2752: }
1.334 djm 2753: } else if (strcmp(listen_addr, "localhost") != 0 ||
2754: strcmp(listen_addr, "127.0.0.1") == 0 ||
2755: strcmp(listen_addr, "::1") == 0) {
2756: /* Accept localhost address when GatewayPorts=yes */
2757: addr = listen_addr;
1.326 djm 2758: }
1.334 djm 2759: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
2760: strcmp(listen_addr, "::1") == 0) {
2761: /*
2762: * If a specific IPv4/IPv6 localhost address has been
2763: * requested then accept it even if gateway_ports is in
2764: * effect. This allows the client to prefer IPv4 or IPv6.
2765: */
2766: addr = listen_addr;
1.312 djm 2767: }
2768: if (wildcardp != NULL)
2769: *wildcardp = wildcard;
2770: return addr;
2771: }
2772:
1.160 markus 2773: static int
1.336 millert 2774: channel_setup_fwd_listener_tcpip(int type, struct Forward *fwd,
2775: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.25 markus 2776: {
1.113 markus 2777: Channel *c;
1.226 djm 2778: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 2779: struct addrinfo hints, *ai, *aitop;
1.212 djm 2780: const char *host, *addr;
1.35 markus 2781: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 2782: in_port_t *lport_p;
1.25 markus 2783:
1.212 djm 2784: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 2785:
1.344 millert 2786: if (is_client && fwd->connect_path != NULL) {
2787: host = fwd->connect_path;
2788: } else {
2789: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
2790: fwd->listen_host : fwd->connect_host;
2791: if (host == NULL) {
2792: error("No forward host name.");
2793: return 0;
2794: }
2795: if (strlen(host) >= NI_MAXHOST) {
2796: error("Forward host name too long.");
2797: return 0;
2798: }
1.87 markus 2799: }
1.25 markus 2800:
1.312 djm 2801: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.336 millert 2802: addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard,
2803: is_client, fwd_opts);
2804: debug3("%s: type %d wildcard %d addr %s", __func__,
1.212 djm 2805: type, wildcard, (addr == NULL) ? "NULL" : addr);
2806:
2807: /*
1.35 markus 2808: * getaddrinfo returns a loopback address if the hostname is
2809: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 2810: */
1.35 markus 2811: memset(&hints, 0, sizeof(hints));
2812: hints.ai_family = IPv4or6;
1.212 djm 2813: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 2814: hints.ai_socktype = SOCK_STREAM;
1.336 millert 2815: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 2816: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
2817: if (addr == NULL) {
2818: /* This really shouldn't happen */
2819: packet_disconnect("getaddrinfo: fatal error: %s",
1.271 dtucker 2820: ssh_gai_strerror(r));
1.212 djm 2821: } else {
1.336 millert 2822: error("%s: getaddrinfo(%.64s): %s", __func__, addr,
1.271 dtucker 2823: ssh_gai_strerror(r));
1.212 djm 2824: }
1.218 markus 2825: return 0;
1.212 djm 2826: }
1.295 djm 2827: if (allocated_listen_port != NULL)
2828: *allocated_listen_port = 0;
1.35 markus 2829: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 2830: switch (ai->ai_family) {
2831: case AF_INET:
2832: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
2833: sin_port;
2834: break;
2835: case AF_INET6:
2836: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
2837: sin6_port;
2838: break;
2839: default:
1.35 markus 2840: continue;
1.295 djm 2841: }
2842: /*
2843: * If allocating a port for -R forwards, then use the
2844: * same port for all address families.
2845: */
1.336 millert 2846: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2847: allocated_listen_port != NULL && *allocated_listen_port > 0)
2848: *lport_p = htons(*allocated_listen_port);
2849:
1.35 markus 2850: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
2851: strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.336 millert 2852: error("%s: getnameinfo failed", __func__);
1.35 markus 2853: continue;
2854: }
2855: /* Create a port to listen for the host. */
1.300 dtucker 2856: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 2857: if (sock < 0) {
2858: /* this is no error since kernel may not support ipv6 */
2859: verbose("socket: %.100s", strerror(errno));
2860: continue;
2861: }
1.226 djm 2862:
2863: channel_set_reuseaddr(sock);
1.182 stevesk 2864:
1.295 djm 2865: debug("Local forwarding listening on %s port %s.",
2866: ntop, strport);
1.35 markus 2867:
2868: /* Bind the socket to the address. */
2869: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2870: /* address can be in use ipv6 address is already bound */
2871: verbose("bind: %.100s", strerror(errno));
2872: close(sock);
2873: continue;
2874: }
2875: /* Start listening for connections on the socket. */
1.199 markus 2876: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 2877: error("listen: %.100s", strerror(errno));
2878: close(sock);
2879: continue;
2880: }
1.295 djm 2881:
2882: /*
1.336 millert 2883: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 2884: * record what we got.
2885: */
1.336 millert 2886: if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 &&
1.295 djm 2887: allocated_listen_port != NULL &&
2888: *allocated_listen_port == 0) {
2889: *allocated_listen_port = get_sock_port(sock, 1);
2890: debug("Allocated listen port %d",
2891: *allocated_listen_port);
2892: }
2893:
1.35 markus 2894: /* Allocate a channel number for the socket. */
1.121 markus 2895: c = channel_new("port listener", type, sock, sock, -1,
1.51 markus 2896: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 2897: 0, "port listener", 1);
1.293 djm 2898: c->path = xstrdup(host);
1.336 millert 2899: c->host_port = fwd->connect_port;
1.312 djm 2900: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 2901: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.315 markus 2902: !(datafellows & SSH_BUG_DYNAMIC_RPORT))
2903: c->listening_port = *allocated_listen_port;
2904: else
1.336 millert 2905: c->listening_port = fwd->listen_port;
1.35 markus 2906: success = 1;
2907: }
2908: if (success == 0)
1.336 millert 2909: error("%s: cannot listen to port: %d", __func__,
2910: fwd->listen_port);
1.35 markus 2911: freeaddrinfo(aitop);
1.87 markus 2912: return success;
1.25 markus 2913: }
1.1 deraadt 2914:
1.336 millert 2915: static int
2916: channel_setup_fwd_listener_streamlocal(int type, struct Forward *fwd,
2917: struct ForwardOptions *fwd_opts)
2918: {
2919: struct sockaddr_un sunaddr;
2920: const char *path;
2921: Channel *c;
2922: int port, sock;
2923: mode_t omask;
2924:
2925: switch (type) {
2926: case SSH_CHANNEL_UNIX_LISTENER:
2927: if (fwd->connect_path != NULL) {
2928: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
2929: error("Local connecting path too long: %s",
2930: fwd->connect_path);
2931: return 0;
2932: }
2933: path = fwd->connect_path;
2934: port = PORT_STREAMLOCAL;
2935: } else {
2936: if (fwd->connect_host == NULL) {
2937: error("No forward host name.");
2938: return 0;
2939: }
2940: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
2941: error("Forward host name too long.");
2942: return 0;
2943: }
2944: path = fwd->connect_host;
2945: port = fwd->connect_port;
2946: }
2947: break;
2948: case SSH_CHANNEL_RUNIX_LISTENER:
2949: path = fwd->listen_path;
2950: port = PORT_STREAMLOCAL;
2951: break;
2952: default:
2953: error("%s: unexpected channel type %d", __func__, type);
2954: return 0;
2955: }
2956:
2957: if (fwd->listen_path == NULL) {
2958: error("No forward path name.");
2959: return 0;
2960: }
2961: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
2962: error("Local listening path too long: %s", fwd->listen_path);
2963: return 0;
2964: }
2965:
2966: debug3("%s: type %d path %s", __func__, type, fwd->listen_path);
2967:
2968: /* Start a Unix domain listener. */
2969: omask = umask(fwd_opts->streamlocal_bind_mask);
2970: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
2971: fwd_opts->streamlocal_bind_unlink);
2972: umask(omask);
2973: if (sock < 0)
2974: return 0;
2975:
2976: debug("Local forwarding listening on path %s.", fwd->listen_path);
2977:
2978: /* Allocate a channel number for the socket. */
2979: c = channel_new("unix listener", type, sock, sock, -1,
2980: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
2981: 0, "unix listener", 1);
2982: c->path = xstrdup(path);
2983: c->host_port = port;
2984: c->listening_port = PORT_STREAMLOCAL;
2985: c->listening_addr = xstrdup(fwd->listen_path);
2986: return 1;
2987: }
2988:
2989: static int
2990: channel_cancel_rport_listener_tcpip(const char *host, u_short port)
1.202 djm 2991: {
1.209 avsm 2992: u_int i;
2993: int found = 0;
1.202 djm 2994:
1.213 deraadt 2995: for (i = 0; i < channels_alloc; i++) {
1.202 djm 2996: Channel *c = channels[i];
1.312 djm 2997: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
2998: continue;
2999: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
3000: debug2("%s: close channel %d", __func__, i);
3001: channel_free(c);
3002: found = 1;
3003: }
3004: }
3005:
3006: return (found);
3007: }
3008:
1.336 millert 3009: static int
3010: channel_cancel_rport_listener_streamlocal(const char *path)
3011: {
3012: u_int i;
3013: int found = 0;
3014:
3015: for (i = 0; i < channels_alloc; i++) {
3016: Channel *c = channels[i];
3017: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3018: continue;
3019: if (c->path == NULL)
3020: continue;
3021: if (strcmp(c->path, path) == 0) {
3022: debug2("%s: close channel %d", __func__, i);
3023: channel_free(c);
3024: found = 1;
3025: }
3026: }
3027:
3028: return (found);
3029: }
3030:
1.312 djm 3031: int
1.336 millert 3032: channel_cancel_rport_listener(struct Forward *fwd)
3033: {
3034: if (fwd->listen_path != NULL)
3035: return channel_cancel_rport_listener_streamlocal(fwd->listen_path);
3036: else
3037: return channel_cancel_rport_listener_tcpip(fwd->listen_host, fwd->listen_port);
3038: }
3039:
3040: static int
3041: channel_cancel_lport_listener_tcpip(const char *lhost, u_short lport,
3042: int cport, struct ForwardOptions *fwd_opts)
1.312 djm 3043: {
3044: u_int i;
3045: int found = 0;
1.336 millert 3046: const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts);
1.202 djm 3047:
1.312 djm 3048: for (i = 0; i < channels_alloc; i++) {
3049: Channel *c = channels[i];
3050: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3051: continue;
1.313 markus 3052: if (c->listening_port != lport)
1.312 djm 3053: continue;
1.313 markus 3054: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3055: /* skip dynamic forwardings */
3056: if (c->host_port == 0)
3057: continue;
3058: } else {
3059: if (c->host_port != cport)
3060: continue;
3061: }
1.312 djm 3062: if ((c->listening_addr == NULL && addr != NULL) ||
3063: (c->listening_addr != NULL && addr == NULL))
3064: continue;
3065: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.210 djm 3066: debug2("%s: close channel %d", __func__, i);
1.202 djm 3067: channel_free(c);
3068: found = 1;
3069: }
3070: }
3071:
3072: return (found);
3073: }
3074:
1.336 millert 3075: static int
3076: channel_cancel_lport_listener_streamlocal(const char *path)
3077: {
3078: u_int i;
3079: int found = 0;
3080:
3081: if (path == NULL) {
3082: error("%s: no path specified.", __func__);
3083: return 0;
3084: }
3085:
3086: for (i = 0; i < channels_alloc; i++) {
3087: Channel *c = channels[i];
3088: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3089: continue;
3090: if (c->listening_addr == NULL)
3091: continue;
3092: if (strcmp(c->listening_addr, path) == 0) {
3093: debug2("%s: close channel %d", __func__, i);
3094: channel_free(c);
3095: found = 1;
3096: }
3097: }
3098:
3099: return (found);
3100: }
3101:
3102: int
3103: channel_cancel_lport_listener(struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
3104: {
3105: if (fwd->listen_path != NULL)
3106: return channel_cancel_lport_listener_streamlocal(fwd->listen_path);
3107: else
3108: return channel_cancel_lport_listener_tcpip(fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3109: }
3110:
1.160 markus 3111: /* protocol local port fwd, used by ssh (and sshd in v1) */
3112: int
1.336 millert 3113: channel_setup_local_fwd_listener(struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3114: {
1.336 millert 3115: if (fwd->listen_path != NULL) {
3116: return channel_setup_fwd_listener_streamlocal(
3117: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3118: } else {
3119: return channel_setup_fwd_listener_tcpip(SSH_CHANNEL_PORT_LISTENER,
3120: fwd, NULL, fwd_opts);
3121: }
1.160 markus 3122: }
3123:
3124: /* protocol v2 remote port fwd, used by sshd */
3125: int
1.336 millert 3126: channel_setup_remote_fwd_listener(struct Forward *fwd,
3127: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3128: {
1.336 millert 3129: if (fwd->listen_path != NULL) {
3130: return channel_setup_fwd_listener_streamlocal(
3131: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3132: } else {
3133: return channel_setup_fwd_listener_tcpip(
3134: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3135: fwd_opts);
3136: }
1.160 markus 3137: }
3138:
1.27 markus 3139: /*
1.312 djm 3140: * Translate the requested rfwd listen host to something usable for
3141: * this server.
3142: */
3143: static const char *
3144: channel_rfwd_bind_host(const char *listen_host)
3145: {
3146: if (listen_host == NULL) {
3147: if (datafellows & SSH_BUG_RFWD_ADDR)
3148: return "127.0.0.1";
3149: else
3150: return "localhost";
3151: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
3152: if (datafellows & SSH_BUG_RFWD_ADDR)
3153: return "0.0.0.0";
3154: else
3155: return "";
3156: } else
3157: return listen_host;
3158: }
3159:
3160: /*
1.27 markus 3161: * Initiate forwarding of connections to port "port" on remote host through
3162: * the secure channel to host:port from local side.
1.315 markus 3163: * Returns handle (index) for updating the dynamic listen port with
3164: * channel_update_permitted_opens().
1.27 markus 3165: */
1.253 markus 3166: int
1.336 millert 3167: channel_request_remote_forwarding(struct Forward *fwd)
1.25 markus 3168: {
1.315 markus 3169: int type, success = 0, idx = -1;
1.73 markus 3170:
1.25 markus 3171: /* Send the forward request to the remote side. */
1.44 markus 3172: if (compat20) {
3173: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1.336 millert 3174: if (fwd->listen_path != NULL) {
3175: packet_put_cstring("streamlocal-forward@openssh.com");
3176: packet_put_char(1); /* boolean: want reply */
3177: packet_put_cstring(fwd->listen_path);
3178: } else {
3179: packet_put_cstring("tcpip-forward");
3180: packet_put_char(1); /* boolean: want reply */
3181: packet_put_cstring(channel_rfwd_bind_host(fwd->listen_host));
3182: packet_put_int(fwd->listen_port);
3183: }
1.73 markus 3184: packet_send();
3185: packet_write_wait();
3186: /* Assume that server accepts the request */
3187: success = 1;
1.336 millert 3188: } else if (fwd->listen_path == NULL) {
1.44 markus 3189: packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1.336 millert 3190: packet_put_int(fwd->listen_port);
3191: packet_put_cstring(fwd->connect_host);
3192: packet_put_int(fwd->connect_port);
1.44 markus 3193: packet_send();
3194: packet_write_wait();
1.73 markus 3195:
3196: /* Wait for response from the remote side. */
1.153 markus 3197: type = packet_read();
1.73 markus 3198: switch (type) {
3199: case SSH_SMSG_SUCCESS:
3200: success = 1;
3201: break;
3202: case SSH_SMSG_FAILURE:
3203: break;
3204: default:
3205: /* Unknown packet */
3206: packet_disconnect("Protocol error for port forward request:"
3207: "received packet type %d.", type);
3208: }
1.336 millert 3209: } else {
3210: logit("Warning: Server does not support remote stream local forwarding.");
1.73 markus 3211: }
3212: if (success) {
1.305 djm 3213: /* Record that connection to this host/port is permitted. */
1.342 deraadt 3214: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3215: num_permitted_opens + 1, sizeof(*permitted_opens));
1.315 markus 3216: idx = num_permitted_opens++;
1.336 millert 3217: if (fwd->connect_path != NULL) {
3218: permitted_opens[idx].host_to_connect =
3219: xstrdup(fwd->connect_path);
3220: permitted_opens[idx].port_to_connect =
3221: PORT_STREAMLOCAL;
3222: } else {
3223: permitted_opens[idx].host_to_connect =
3224: xstrdup(fwd->connect_host);
3225: permitted_opens[idx].port_to_connect =
3226: fwd->connect_port;
3227: }
3228: if (fwd->listen_path != NULL) {
3229: permitted_opens[idx].listen_host = NULL;
3230: permitted_opens[idx].listen_path =
3231: xstrdup(fwd->listen_path);
3232: permitted_opens[idx].listen_port = PORT_STREAMLOCAL;
3233: } else {
3234: permitted_opens[idx].listen_host =
3235: fwd->listen_host ? xstrdup(fwd->listen_host) : NULL;
3236: permitted_opens[idx].listen_path = NULL;
3237: permitted_opens[idx].listen_port = fwd->listen_port;
3238: }
1.44 markus 3239: }
1.315 markus 3240: return (idx);
1.1 deraadt 3241: }
3242:
1.333 markus 3243: static int
3244: open_match(ForwardPermission *allowed_open, const char *requestedhost,
1.336 millert 3245: int requestedport)
1.333 markus 3246: {
3247: if (allowed_open->host_to_connect == NULL)
3248: return 0;
3249: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3250: allowed_open->port_to_connect != requestedport)
3251: return 0;
3252: if (strcmp(allowed_open->host_to_connect, requestedhost) != 0)
3253: return 0;
3254: return 1;
3255: }
3256:
3257: /*
1.336 millert 3258: * Note that in the listen host/port case
1.333 markus 3259: * we don't support FWD_PERMIT_ANY_PORT and
3260: * need to translate between the configured-host (listen_host)
3261: * and what we've sent to the remote server (channel_rfwd_bind_host)
3262: */
3263: static int
1.336 millert 3264: open_listen_match_tcpip(ForwardPermission *allowed_open,
3265: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3266: {
3267: const char *allowed_host;
3268:
3269: if (allowed_open->host_to_connect == NULL)
3270: return 0;
3271: if (allowed_open->listen_port != requestedport)
3272: return 0;
1.335 djm 3273: if (!translate && allowed_open->listen_host == NULL &&
3274: requestedhost == NULL)
3275: return 1;
1.333 markus 3276: allowed_host = translate ?
3277: channel_rfwd_bind_host(allowed_open->listen_host) :
3278: allowed_open->listen_host;
3279: if (allowed_host == NULL ||
3280: strcmp(allowed_host, requestedhost) != 0)
3281: return 0;
3282: return 1;
3283: }
3284:
1.336 millert 3285: static int
3286: open_listen_match_streamlocal(ForwardPermission *allowed_open,
3287: const char *requestedpath)
3288: {
3289: if (allowed_open->host_to_connect == NULL)
3290: return 0;
3291: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3292: return 0;
3293: if (allowed_open->listen_path == NULL ||
3294: strcmp(allowed_open->listen_path, requestedpath) != 0)
3295: return 0;
3296: return 1;
3297: }
3298:
1.27 markus 3299: /*
1.208 deraadt 3300: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3301: * local side.
3302: */
1.336 millert 3303: static int
3304: channel_request_rforward_cancel_tcpip(const char *host, u_short port)
1.202 djm 3305: {
3306: int i;
3307:
3308: if (!compat20)
1.312 djm 3309: return -1;
1.202 djm 3310:
3311: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3312: if (open_listen_match_tcpip(&permitted_opens[i], host, port, 0))
1.202 djm 3313: break;
3314: }
3315: if (i >= num_permitted_opens) {
3316: debug("%s: requested forward not found", __func__);
1.312 djm 3317: return -1;
1.202 djm 3318: }
3319: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3320: packet_put_cstring("cancel-tcpip-forward");
3321: packet_put_char(0);
1.312 djm 3322: packet_put_cstring(channel_rfwd_bind_host(host));
1.202 djm 3323: packet_put_int(port);
3324: packet_send();
3325:
1.336 millert 3326: permitted_opens[i].listen_port = 0;
1.333 markus 3327: permitted_opens[i].port_to_connect = 0;
1.336 millert 3328: free(permitted_opens[i].host_to_connect);
3329: permitted_opens[i].host_to_connect = NULL;
3330: free(permitted_opens[i].listen_host);
3331: permitted_opens[i].listen_host = NULL;
3332: permitted_opens[i].listen_path = NULL;
3333:
3334: return 0;
3335: }
3336:
3337: /*
3338: * Request cancellation of remote forwarding of Unix domain socket
3339: * path from local side.
3340: */
3341: static int
3342: channel_request_rforward_cancel_streamlocal(const char *path)
3343: {
3344: int i;
3345:
3346: if (!compat20)
3347: return -1;
3348:
3349: for (i = 0; i < num_permitted_opens; i++) {
3350: if (open_listen_match_streamlocal(&permitted_opens[i], path))
3351: break;
3352: }
3353: if (i >= num_permitted_opens) {
3354: debug("%s: requested forward not found", __func__);
3355: return -1;
3356: }
3357: packet_start(SSH2_MSG_GLOBAL_REQUEST);
3358: packet_put_cstring("cancel-streamlocal-forward@openssh.com");
3359: packet_put_char(0);
3360: packet_put_cstring(path);
3361: packet_send();
3362:
1.202 djm 3363: permitted_opens[i].listen_port = 0;
1.336 millert 3364: permitted_opens[i].port_to_connect = 0;
1.321 djm 3365: free(permitted_opens[i].host_to_connect);
1.202 djm 3366: permitted_opens[i].host_to_connect = NULL;
1.333 markus 3367: permitted_opens[i].listen_host = NULL;
1.336 millert 3368: free(permitted_opens[i].listen_path);
3369: permitted_opens[i].listen_path = NULL;
1.312 djm 3370:
3371: return 0;
1.202 djm 3372: }
3373:
3374: /*
1.336 millert 3375: * Request cancellation of remote forwarding of a connection from local side.
3376: */
3377: int
3378: channel_request_rforward_cancel(struct Forward *fwd)
3379: {
3380: if (fwd->listen_path != NULL) {
3381: return (channel_request_rforward_cancel_streamlocal(
3382: fwd->listen_path));
3383: } else {
3384: return (channel_request_rforward_cancel_tcpip(fwd->listen_host,
3385: fwd->listen_port ? fwd->listen_port : fwd->allocated_port));
3386: }
3387: }
3388:
3389: /*
1.27 markus 3390: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
3391: * listening for the port, and sends back a success reply (or disconnect
1.253 markus 3392: * message if there was an error).
1.27 markus 3393: */
1.253 markus 3394: int
1.336 millert 3395: channel_input_port_forward_request(int is_root, struct ForwardOptions *fwd_opts)
1.1 deraadt 3396: {
1.253 markus 3397: int success = 0;
1.336 millert 3398: struct Forward fwd;
1.1 deraadt 3399:
1.25 markus 3400: /* Get arguments from the packet. */
1.336 millert 3401: memset(&fwd, 0, sizeof(fwd));
3402: fwd.listen_port = packet_get_int();
3403: fwd.connect_host = packet_get_string(NULL);
3404: fwd.connect_port = packet_get_int();
1.25 markus 3405:
1.27 markus 3406: /*
3407: * Check that an unprivileged user is not trying to forward a
3408: * privileged port.
3409: */
1.336 millert 3410: if (fwd.listen_port < IPPORT_RESERVED && !is_root)
1.192 markus 3411: packet_disconnect(
3412: "Requested forwarding of port %d but user is not root.",
1.336 millert 3413: fwd.listen_port);
3414: if (fwd.connect_port == 0)
1.192 markus 3415: packet_disconnect("Dynamic forwarding denied.");
3416:
1.73 markus 3417: /* Initiate forwarding */
1.336 millert 3418: success = channel_setup_local_fwd_listener(&fwd, fwd_opts);
1.25 markus 3419:
3420: /* Free the argument string. */
1.336 millert 3421: free(fwd.connect_host);
1.253 markus 3422:
3423: return (success ? 0 : -1);
1.1 deraadt 3424: }
3425:
1.99 markus 3426: /*
3427: * Permits opening to any host/port if permitted_opens[] is empty. This is
3428: * usually called by the server, because the user could connect to any port
3429: * anyway, and the server has no way to know but to trust the client anyway.
3430: */
3431: void
1.142 itojun 3432: channel_permit_all_opens(void)
1.99 markus 3433: {
3434: if (num_permitted_opens == 0)
3435: all_opens_permitted = 1;
3436: }
3437:
1.101 markus 3438: void
1.99 markus 3439: channel_add_permitted_opens(char *host, int port)
3440: {
3441: debug("allow port forwarding to host %s port %d", host, port);
3442:
1.342 deraadt 3443: permitted_opens = xreallocarray(permitted_opens,
1.305 djm 3444: num_permitted_opens + 1, sizeof(*permitted_opens));
1.99 markus 3445: permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
3446: permitted_opens[num_permitted_opens].port_to_connect = port;
1.333 markus 3447: permitted_opens[num_permitted_opens].listen_host = NULL;
1.336 millert 3448: permitted_opens[num_permitted_opens].listen_path = NULL;
1.333 markus 3449: permitted_opens[num_permitted_opens].listen_port = 0;
1.99 markus 3450: num_permitted_opens++;
3451:
3452: all_opens_permitted = 0;
1.315 markus 3453: }
3454:
3455: /*
3456: * Update the listen port for a dynamic remote forward, after
3457: * the actual 'newport' has been allocated. If 'newport' < 0 is
3458: * passed then they entry will be invalidated.
3459: */
3460: void
3461: channel_update_permitted_opens(int idx, int newport)
3462: {
3463: if (idx < 0 || idx >= num_permitted_opens) {
3464: debug("channel_update_permitted_opens: index out of range:"
3465: " %d num_permitted_opens %d", idx, num_permitted_opens);
3466: return;
3467: }
3468: debug("%s allowed port %d for forwarding to host %s port %d",
3469: newport > 0 ? "Updating" : "Removing",
3470: newport,
3471: permitted_opens[idx].host_to_connect,
3472: permitted_opens[idx].port_to_connect);
3473: if (newport >= 0) {
3474: permitted_opens[idx].listen_port =
3475: (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
3476: } else {
3477: permitted_opens[idx].listen_port = 0;
3478: permitted_opens[idx].port_to_connect = 0;
1.321 djm 3479: free(permitted_opens[idx].host_to_connect);
1.315 markus 3480: permitted_opens[idx].host_to_connect = NULL;
1.333 markus 3481: free(permitted_opens[idx].listen_host);
3482: permitted_opens[idx].listen_host = NULL;
1.336 millert 3483: free(permitted_opens[idx].listen_path);
3484: permitted_opens[idx].listen_path = NULL;
1.315 markus 3485: }
1.99 markus 3486: }
3487:
1.258 dtucker 3488: int
1.257 dtucker 3489: channel_add_adm_permitted_opens(char *host, int port)
3490: {
1.258 dtucker 3491: debug("config allows port forwarding to host %s port %d", host, port);
1.257 dtucker 3492:
1.342 deraadt 3493: permitted_adm_opens = xreallocarray(permitted_adm_opens,
1.305 djm 3494: num_adm_permitted_opens + 1, sizeof(*permitted_adm_opens));
1.257 dtucker 3495: permitted_adm_opens[num_adm_permitted_opens].host_to_connect
3496: = xstrdup(host);
3497: permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port;
1.333 markus 3498: permitted_adm_opens[num_adm_permitted_opens].listen_host = NULL;
1.336 millert 3499: permitted_adm_opens[num_adm_permitted_opens].listen_path = NULL;
1.333 markus 3500: permitted_adm_opens[num_adm_permitted_opens].listen_port = 0;
1.258 dtucker 3501: return ++num_adm_permitted_opens;
1.257 dtucker 3502: }
3503:
3504: void
1.316 dtucker 3505: channel_disable_adm_local_opens(void)
3506: {
1.319 djm 3507: channel_clear_adm_permitted_opens();
1.343 dtucker 3508: permitted_adm_opens = xcalloc(sizeof(*permitted_adm_opens), 1);
1.319 djm 3509: permitted_adm_opens[num_adm_permitted_opens].host_to_connect = NULL;
3510: num_adm_permitted_opens = 1;
1.316 dtucker 3511: }
3512:
3513: void
1.99 markus 3514: channel_clear_permitted_opens(void)
3515: {
3516: int i;
3517:
1.333 markus 3518: for (i = 0; i < num_permitted_opens; i++) {
1.321 djm 3519: free(permitted_opens[i].host_to_connect);
1.333 markus 3520: free(permitted_opens[i].listen_host);
1.336 millert 3521: free(permitted_opens[i].listen_path);
1.333 markus 3522: }
1.321 djm 3523: free(permitted_opens);
3524: permitted_opens = NULL;
1.99 markus 3525: num_permitted_opens = 0;
1.257 dtucker 3526: }
3527:
3528: void
3529: channel_clear_adm_permitted_opens(void)
3530: {
3531: int i;
1.99 markus 3532:
1.333 markus 3533: for (i = 0; i < num_adm_permitted_opens; i++) {
1.321 djm 3534: free(permitted_adm_opens[i].host_to_connect);
1.333 markus 3535: free(permitted_adm_opens[i].listen_host);
1.336 millert 3536: free(permitted_adm_opens[i].listen_path);
1.333 markus 3537: }
1.321 djm 3538: free(permitted_adm_opens);
3539: permitted_adm_opens = NULL;
1.257 dtucker 3540: num_adm_permitted_opens = 0;
1.278 dtucker 3541: }
3542:
3543: void
3544: channel_print_adm_permitted_opens(void)
3545: {
1.286 djm 3546: int i;
1.278 dtucker 3547:
1.290 stevesk 3548: printf("permitopen");
1.288 stevesk 3549: if (num_adm_permitted_opens == 0) {
1.290 stevesk 3550: printf(" any\n");
1.288 stevesk 3551: return;
3552: }
1.278 dtucker 3553: for (i = 0; i < num_adm_permitted_opens; i++)
1.316 dtucker 3554: if (permitted_adm_opens[i].host_to_connect == NULL)
3555: printf(" none");
3556: else
1.278 dtucker 3557: printf(" %s:%d", permitted_adm_opens[i].host_to_connect,
3558: permitted_adm_opens[i].port_to_connect);
1.290 stevesk 3559: printf("\n");
1.99 markus 3560: }
3561:
1.314 dtucker 3562: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3563: int
3564: permitopen_port(const char *p)
3565: {
3566: int port;
3567:
3568: if (strcmp(p, "*") == 0)
3569: return FWD_PERMIT_ANY_PORT;
3570: if ((port = a2port(p)) > 0)
3571: return port;
3572: return -1;
3573: }
3574:
1.276 djm 3575: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 3576: static int
1.276 djm 3577: connect_next(struct channel_connect *cctx)
1.41 markus 3578: {
1.276 djm 3579: int sock, saved_errno;
1.336 millert 3580: struct sockaddr_un *sunaddr;
3581: char ntop[NI_MAXHOST], strport[MAX(NI_MAXSERV,sizeof(sunaddr->sun_path))];
1.41 markus 3582:
1.276 djm 3583: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 3584: switch (cctx->ai->ai_family) {
3585: case AF_UNIX:
3586: /* unix:pathname instead of host:port */
3587: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
3588: strlcpy(ntop, "unix", sizeof(ntop));
3589: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
3590: break;
3591: case AF_INET:
3592: case AF_INET6:
3593: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
3594: ntop, sizeof(ntop), strport, sizeof(strport),
3595: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
3596: error("connect_next: getnameinfo failed");
3597: continue;
3598: }
3599: break;
3600: default:
1.41 markus 3601: continue;
3602: }
1.300 dtucker 3603: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
3604: cctx->ai->ai_protocol)) == -1) {
1.276 djm 3605: if (cctx->ai->ai_next == NULL)
1.186 djm 3606: error("socket: %.100s", strerror(errno));
3607: else
3608: verbose("socket: %.100s", strerror(errno));
1.41 markus 3609: continue;
3610: }
1.205 djm 3611: if (set_nonblock(sock) == -1)
3612: fatal("%s: set_nonblock(%d)", __func__, sock);
1.276 djm 3613: if (connect(sock, cctx->ai->ai_addr,
3614: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
3615: debug("connect_next: host %.100s ([%.100s]:%s): "
3616: "%.100s", cctx->host, ntop, strport,
1.41 markus 3617: strerror(errno));
1.276 djm 3618: saved_errno = errno;
1.41 markus 3619: close(sock);
1.276 djm 3620: errno = saved_errno;
1.89 stevesk 3621: continue; /* fail -- try next */
1.41 markus 3622: }
1.336 millert 3623: if (cctx->ai->ai_family != AF_UNIX)
3624: set_nodelay(sock);
1.276 djm 3625: debug("connect_next: host %.100s ([%.100s]:%s) "
3626: "in progress, fd=%d", cctx->host, ntop, strport, sock);
3627: cctx->ai = cctx->ai->ai_next;
3628: return sock;
3629: }
3630: return -1;
3631: }
1.41 markus 3632:
1.276 djm 3633: static void
3634: channel_connect_ctx_free(struct channel_connect *cctx)
3635: {
1.321 djm 3636: free(cctx->host);
1.336 millert 3637: if (cctx->aitop) {
3638: if (cctx->aitop->ai_family == AF_UNIX)
3639: free(cctx->aitop);
3640: else
3641: freeaddrinfo(cctx->aitop);
3642: }
1.329 tedu 3643: memset(cctx, 0, sizeof(*cctx));
1.276 djm 3644: }
3645:
1.336 millert 3646: /* Return CONNECTING channel to remote host:port or local socket path */
1.276 djm 3647: static Channel *
1.336 millert 3648: connect_to(const char *name, int port, char *ctype, char *rname)
1.276 djm 3649: {
3650: struct addrinfo hints;
3651: int gaierr;
3652: int sock = -1;
3653: char strport[NI_MAXSERV];
3654: struct channel_connect cctx;
3655: Channel *c;
3656:
1.284 djm 3657: memset(&cctx, 0, sizeof(cctx));
1.336 millert 3658:
3659: if (port == PORT_STREAMLOCAL) {
3660: struct sockaddr_un *sunaddr;
3661: struct addrinfo *ai;
3662:
3663: if (strlen(name) > sizeof(sunaddr->sun_path)) {
3664: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
3665: return (NULL);
3666: }
3667:
3668: /*
3669: * Fake up a struct addrinfo for AF_UNIX connections.
3670: * channel_connect_ctx_free() must check ai_family
3671: * and use free() not freeaddirinfo() for AF_UNIX.
3672: */
3673: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
3674: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
3675: ai->ai_addr = (struct sockaddr *)(ai + 1);
3676: ai->ai_addrlen = sizeof(*sunaddr);
3677: ai->ai_family = AF_UNIX;
3678: ai->ai_socktype = SOCK_STREAM;
3679: ai->ai_protocol = PF_UNSPEC;
3680: sunaddr = (struct sockaddr_un *)ai->ai_addr;
3681: sunaddr->sun_family = AF_UNIX;
3682: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
3683: cctx.aitop = ai;
3684: } else {
3685: memset(&hints, 0, sizeof(hints));
3686: hints.ai_family = IPv4or6;
3687: hints.ai_socktype = SOCK_STREAM;
3688: snprintf(strport, sizeof strport, "%d", port);
3689: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx.aitop)) != 0) {
3690: error("connect_to %.100s: unknown host (%s)", name,
3691: ssh_gai_strerror(gaierr));
3692: return NULL;
3693: }
1.41 markus 3694: }
1.276 djm 3695:
1.336 millert 3696: cctx.host = xstrdup(name);
1.276 djm 3697: cctx.port = port;
3698: cctx.ai = cctx.aitop;
3699:
3700: if ((sock = connect_next(&cctx)) == -1) {
3701: error("connect to %.100s port %d failed: %s",
1.336 millert 3702: name, port, strerror(errno));
1.276 djm 3703: channel_connect_ctx_free(&cctx);
3704: return NULL;
1.41 markus 3705: }
1.276 djm 3706: c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
3707: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
3708: c->connect_ctx = cctx;
3709: return c;
1.41 markus 3710: }
1.99 markus 3711:
1.276 djm 3712: Channel *
1.333 markus 3713: channel_connect_by_listen_address(const char *listen_host,
3714: u_short listen_port, char *ctype, char *rname)
1.73 markus 3715: {
3716: int i;
1.99 markus 3717:
1.276 djm 3718: for (i = 0; i < num_permitted_opens; i++) {
1.336 millert 3719: if (open_listen_match_tcpip(&permitted_opens[i], listen_host,
1.333 markus 3720: listen_port, 1)) {
1.99 markus 3721: return connect_to(
1.73 markus 3722: permitted_opens[i].host_to_connect,
1.276 djm 3723: permitted_opens[i].port_to_connect, ctype, rname);
3724: }
3725: }
1.74 markus 3726: error("WARNING: Server requests forwarding for unknown listen_port %d",
3727: listen_port);
1.276 djm 3728: return NULL;
1.73 markus 3729: }
3730:
1.336 millert 3731: Channel *
3732: channel_connect_by_listen_path(const char *path, char *ctype, char *rname)
3733: {
3734: int i;
3735:
3736: for (i = 0; i < num_permitted_opens; i++) {
3737: if (open_listen_match_streamlocal(&permitted_opens[i], path)) {
3738: return connect_to(
3739: permitted_opens[i].host_to_connect,
3740: permitted_opens[i].port_to_connect, ctype, rname);
3741: }
3742: }
3743: error("WARNING: Server requests forwarding for unknown path %.100s",
3744: path);
3745: return NULL;
3746: }
3747:
1.99 markus 3748: /* Check if connecting to that port is permitted and connect. */
1.276 djm 3749: Channel *
1.336 millert 3750: channel_connect_to_port(const char *host, u_short port, char *ctype, char *rname)
1.99 markus 3751: {
1.257 dtucker 3752: int i, permit, permit_adm = 1;
1.99 markus 3753:
3754: permit = all_opens_permitted;
3755: if (!permit) {
3756: for (i = 0; i < num_permitted_opens; i++)
1.333 markus 3757: if (open_match(&permitted_opens[i], host, port)) {
1.99 markus 3758: permit = 1;
1.333 markus 3759: break;
3760: }
1.257 dtucker 3761: }
1.99 markus 3762:
1.257 dtucker 3763: if (num_adm_permitted_opens > 0) {
3764: permit_adm = 0;
3765: for (i = 0; i < num_adm_permitted_opens; i++)
1.333 markus 3766: if (open_match(&permitted_adm_opens[i], host, port)) {
1.257 dtucker 3767: permit_adm = 1;
1.333 markus 3768: break;
3769: }
1.99 markus 3770: }
1.257 dtucker 3771:
3772: if (!permit || !permit_adm) {
1.188 itojun 3773: logit("Received request to connect to host %.100s port %d, "
1.99 markus 3774: "but the request was denied.", host, port);
1.276 djm 3775: return NULL;
1.99 markus 3776: }
1.276 djm 3777: return connect_to(host, port, ctype, rname);
1.336 millert 3778: }
3779:
3780: /* Check if connecting to that path is permitted and connect. */
3781: Channel *
3782: channel_connect_to_path(const char *path, char *ctype, char *rname)
3783: {
3784: int i, permit, permit_adm = 1;
3785:
3786: permit = all_opens_permitted;
3787: if (!permit) {
3788: for (i = 0; i < num_permitted_opens; i++)
3789: if (open_match(&permitted_opens[i], path, PORT_STREAMLOCAL)) {
3790: permit = 1;
3791: break;
3792: }
3793: }
3794:
3795: if (num_adm_permitted_opens > 0) {
3796: permit_adm = 0;
3797: for (i = 0; i < num_adm_permitted_opens; i++)
3798: if (open_match(&permitted_adm_opens[i], path, PORT_STREAMLOCAL)) {
3799: permit_adm = 1;
3800: break;
3801: }
3802: }
3803:
3804: if (!permit || !permit_adm) {
3805: logit("Received request to connect to path %.100s, "
3806: "but the request was denied.", path);
3807: return NULL;
3808: }
3809: return connect_to(path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 3810: }
3811:
3812: void
3813: channel_send_window_changes(void)
3814: {
1.209 avsm 3815: u_int i;
1.204 djm 3816: struct winsize ws;
3817:
3818: for (i = 0; i < channels_alloc; i++) {
1.213 deraadt 3819: if (channels[i] == NULL || !channels[i]->client_tty ||
1.204 djm 3820: channels[i]->type != SSH_CHANNEL_OPEN)
3821: continue;
3822: if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0)
3823: continue;
3824: channel_request_start(i, "window-change", 0);
1.238 deraadt 3825: packet_put_int((u_int)ws.ws_col);
3826: packet_put_int((u_int)ws.ws_row);
3827: packet_put_int((u_int)ws.ws_xpixel);
3828: packet_put_int((u_int)ws.ws_ypixel);
1.204 djm 3829: packet_send();
3830: }
1.99 markus 3831: }
3832:
1.121 markus 3833: /* -- X11 forwarding */
1.1 deraadt 3834:
1.27 markus 3835: /*
3836: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 3837: * Returns 0 and a suitable display number for the DISPLAY variable
3838: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 3839: */
1.141 stevesk 3840: int
1.163 stevesk 3841: x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
1.222 djm 3842: int single_connection, u_int *display_numberp, int **chanids)
1.1 deraadt 3843: {
1.149 markus 3844: Channel *nc = NULL;
1.31 markus 3845: int display_number, sock;
3846: u_short port;
1.35 markus 3847: struct addrinfo hints, *ai, *aitop;
3848: char strport[NI_MAXSERV];
3849: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 3850:
1.224 markus 3851: if (chanids == NULL)
3852: return -1;
3853:
1.33 markus 3854: for (display_number = x11_display_offset;
1.148 deraadt 3855: display_number < MAX_DISPLAYS;
3856: display_number++) {
1.25 markus 3857: port = 6000 + display_number;
1.35 markus 3858: memset(&hints, 0, sizeof(hints));
3859: hints.ai_family = IPv4or6;
1.163 stevesk 3860: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 3861: hints.ai_socktype = SOCK_STREAM;
3862: snprintf(strport, sizeof strport, "%d", port);
3863: if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1.271 dtucker 3864: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 3865: return -1;
1.25 markus 3866: }
1.35 markus 3867: for (ai = aitop; ai; ai = ai->ai_next) {
3868: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
3869: continue;
1.300 dtucker 3870: sock = socket(ai->ai_family, ai->ai_socktype,
3871: ai->ai_protocol);
1.35 markus 3872: if (sock < 0) {
3873: error("socket: %.100s", strerror(errno));
1.203 markus 3874: freeaddrinfo(aitop);
1.141 stevesk 3875: return -1;
1.35 markus 3876: }
1.226 djm 3877: channel_set_reuseaddr(sock);
1.35 markus 3878: if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.194 markus 3879: debug2("bind port %d: %.100s", port, strerror(errno));
1.35 markus 3880: close(sock);
1.183 itojun 3881:
1.35 markus 3882: for (n = 0; n < num_socks; n++) {
3883: close(socks[n]);
3884: }
3885: num_socks = 0;
3886: break;
3887: }
3888: socks[num_socks++] = sock;
3889: if (num_socks == NUM_SOCKS)
3890: break;
1.25 markus 3891: }
1.83 stevesk 3892: freeaddrinfo(aitop);
1.35 markus 3893: if (num_socks > 0)
3894: break;
1.25 markus 3895: }
3896: if (display_number >= MAX_DISPLAYS) {
3897: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 3898: return -1;
1.25 markus 3899: }
3900: /* Start listening for connections on the socket. */
1.35 markus 3901: for (n = 0; n < num_socks; n++) {
3902: sock = socks[n];
1.199 markus 3903: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.35 markus 3904: error("listen: %.100s", strerror(errno));
3905: close(sock);
1.141 stevesk 3906: return -1;
1.35 markus 3907: }
1.25 markus 3908: }
1.35 markus 3909:
3910: /* Allocate a channel for each socket. */
1.242 djm 3911: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 3912: for (n = 0; n < num_socks; n++) {
3913: sock = socks[n];
1.149 markus 3914: nc = channel_new("x11 listener",
1.51 markus 3915: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
3916: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 3917: 0, "X11 inet listener", 1);
1.167 markus 3918: nc->single_connection = single_connection;
1.224 markus 3919: (*chanids)[n] = nc->self;
1.35 markus 3920: }
1.224 markus 3921: (*chanids)[n] = -1;
1.1 deraadt 3922:
1.141 stevesk 3923: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 3924: *display_numberp = display_number;
3925: return (0);
1.1 deraadt 3926: }
3927:
1.127 itojun 3928: static int
1.77 markus 3929: connect_local_xsocket(u_int dnr)
1.1 deraadt 3930: {
1.25 markus 3931: int sock;
3932: struct sockaddr_un addr;
3933:
1.147 stevesk 3934: sock = socket(AF_UNIX, SOCK_STREAM, 0);
3935: if (sock < 0)
3936: error("socket: %.100s", strerror(errno));
3937: memset(&addr, 0, sizeof(addr));
3938: addr.sun_family = AF_UNIX;
3939: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 3940: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 3941: return sock;
3942: close(sock);
1.25 markus 3943: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
3944: return -1;
1.1 deraadt 3945: }
3946:
1.51 markus 3947: int
3948: x11_connect_display(void)
1.1 deraadt 3949: {
1.248 deraadt 3950: u_int display_number;
1.25 markus 3951: const char *display;
1.51 markus 3952: char buf[1024], *cp;
1.35 markus 3953: struct addrinfo hints, *ai, *aitop;
3954: char strport[NI_MAXSERV];
1.248 deraadt 3955: int gaierr, sock = 0;
1.25 markus 3956:
3957: /* Try to open a socket for the local X server. */
3958: display = getenv("DISPLAY");
3959: if (!display) {
3960: error("DISPLAY not set.");
1.51 markus 3961: return -1;
1.25 markus 3962: }
1.27 markus 3963: /*
3964: * Now we decode the value of the DISPLAY variable and make a
3965: * connection to the real X server.
3966: */
3967:
3968: /*
3969: * Check if it is a unix domain socket. Unix domain displays are in
3970: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
3971: */
1.25 markus 3972: if (strncmp(display, "unix:", 5) == 0 ||
3973: display[0] == ':') {
3974: /* Connect to the unix domain socket. */
1.248 deraadt 3975: if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) {
1.25 markus 3976: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 3977: display);
1.51 markus 3978: return -1;
1.25 markus 3979: }
3980: /* Create a socket. */
3981: sock = connect_local_xsocket(display_number);
3982: if (sock < 0)
1.51 markus 3983: return -1;
1.25 markus 3984:
3985: /* OK, we now have a connection to the display. */
1.51 markus 3986: return sock;
1.25 markus 3987: }
1.27 markus 3988: /*
3989: * Connect to an inet socket. The DISPLAY value is supposedly
3990: * hostname:d[.s], where hostname may also be numeric IP address.
3991: */
1.145 stevesk 3992: strlcpy(buf, display, sizeof(buf));
1.25 markus 3993: cp = strchr(buf, ':');
3994: if (!cp) {
3995: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 3996: return -1;
1.25 markus 3997: }
3998: *cp = 0;
1.27 markus 3999: /* buf now contains the host name. But first we parse the display number. */
1.248 deraadt 4000: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4001: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4002: display);
1.51 markus 4003: return -1;
1.25 markus 4004: }
1.35 markus 4005:
4006: /* Look up the host address */
4007: memset(&hints, 0, sizeof(hints));
4008: hints.ai_family = IPv4or6;
4009: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4010: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4011: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4012: error("%.100s: unknown host. (%s)", buf,
4013: ssh_gai_strerror(gaierr));
1.51 markus 4014: return -1;
1.25 markus 4015: }
1.35 markus 4016: for (ai = aitop; ai; ai = ai->ai_next) {
4017: /* Create a socket. */
1.300 dtucker 4018: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.35 markus 4019: if (sock < 0) {
1.194 markus 4020: debug2("socket: %.100s", strerror(errno));
1.41 markus 4021: continue;
4022: }
4023: /* Connect it to the display. */
4024: if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1.248 deraadt 4025: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4026: 6000 + display_number, strerror(errno));
4027: close(sock);
4028: continue;
4029: }
4030: /* Success */
4031: break;
1.35 markus 4032: }
4033: freeaddrinfo(aitop);
4034: if (!ai) {
1.248 deraadt 4035: error("connect %.100s port %u: %.100s", buf, 6000 + display_number,
1.35 markus 4036: strerror(errno));
1.51 markus 4037: return -1;
1.25 markus 4038: }
1.162 stevesk 4039: set_nodelay(sock);
1.51 markus 4040: return sock;
4041: }
4042:
4043: /*
4044: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
4045: * the remote channel number. We should do whatever we want, and respond
4046: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
4047: */
4048:
1.259 stevesk 4049: /* ARGSUSED */
1.339 markus 4050: int
1.154 markus 4051: x11_input_open(int type, u_int32_t seq, void *ctxt)
1.51 markus 4052: {
1.113 markus 4053: Channel *c = NULL;
4054: int remote_id, sock = 0;
1.51 markus 4055: char *remote_host;
1.25 markus 4056:
1.113 markus 4057: debug("Received X11 open request.");
1.51 markus 4058:
1.113 markus 4059: remote_id = packet_get_int();
1.121 markus 4060:
4061: if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
1.113 markus 4062: remote_host = packet_get_string(NULL);
1.51 markus 4063: } else {
4064: remote_host = xstrdup("unknown (remote did not supply name)");
4065: }
1.152 markus 4066: packet_check_eom();
1.25 markus 4067:
1.51 markus 4068: /* Obtain a connection to the real X display. */
4069: sock = x11_connect_display();
1.113 markus 4070: if (sock != -1) {
4071: /* Allocate a channel for this connection. */
4072: c = channel_new("connected x11 socket",
4073: SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
4074: remote_host, 1);
1.167 markus 4075: c->remote_id = remote_id;
4076: c->force_drain = 1;
1.113 markus 4077: }
1.321 djm 4078: free(remote_host);
1.113 markus 4079: if (c == NULL) {
1.51 markus 4080: /* Send refusal to the remote host. */
4081: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1.113 markus 4082: packet_put_int(remote_id);
1.51 markus 4083: } else {
4084: /* Send a confirmation to the remote host. */
4085: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1.113 markus 4086: packet_put_int(remote_id);
4087: packet_put_int(c->self);
1.51 markus 4088: }
1.113 markus 4089: packet_send();
1.339 markus 4090: return 0;
1.72 markus 4091: }
4092:
4093: /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
1.259 stevesk 4094: /* ARGSUSED */
1.339 markus 4095: int
1.154 markus 4096: deny_input_open(int type, u_int32_t seq, void *ctxt)
1.72 markus 4097: {
4098: int rchan = packet_get_int();
1.180 deraadt 4099:
1.143 deraadt 4100: switch (type) {
1.72 markus 4101: case SSH_SMSG_AGENT_OPEN:
4102: error("Warning: ssh server tried agent forwarding.");
4103: break;
4104: case SSH_SMSG_X11_OPEN:
4105: error("Warning: ssh server tried X11 forwarding.");
4106: break;
4107: default:
1.154 markus 4108: error("deny_input_open: type %d", type);
1.72 markus 4109: break;
4110: }
1.230 stevesk 4111: error("Warning: this is probably a break-in attempt by a malicious server.");
1.72 markus 4112: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
4113: packet_put_int(rchan);
4114: packet_send();
1.339 markus 4115: return 0;
1.1 deraadt 4116: }
4117:
1.27 markus 4118: /*
4119: * Requests forwarding of X11 connections, generates fake authentication
4120: * data, and enables authentication spoofing.
1.121 markus 4121: * This should be called in the client only.
1.27 markus 4122: */
1.49 markus 4123: void
1.215 djm 4124: x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
1.311 djm 4125: const char *proto, const char *data, int want_reply)
1.1 deraadt 4126: {
1.77 markus 4127: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4128: u_int i, value;
1.25 markus 4129: char *new_data;
4130: int screen_number;
4131: const char *cp;
1.207 avsm 4132: u_int32_t rnd = 0;
1.25 markus 4133:
1.220 markus 4134: if (x11_saved_display == NULL)
4135: x11_saved_display = xstrdup(disp);
4136: else if (strcmp(disp, x11_saved_display) != 0) {
1.219 djm 4137: error("x11_request_forwarding_with_spoofing: different "
4138: "$DISPLAY already forwarded");
4139: return;
4140: }
4141:
1.266 djm 4142: cp = strchr(disp, ':');
1.25 markus 4143: if (cp)
4144: cp = strchr(cp, '.');
4145: if (cp)
1.245 deraadt 4146: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4147: else
4148: screen_number = 0;
4149:
1.219 djm 4150: if (x11_saved_proto == NULL) {
4151: /* Save protocol name. */
4152: x11_saved_proto = xstrdup(proto);
4153: /*
1.221 djm 4154: * Extract real authentication data and generate fake data
1.219 djm 4155: * of the same length.
4156: */
4157: x11_saved_data = xmalloc(data_len);
4158: x11_fake_data = xmalloc(data_len);
4159: for (i = 0; i < data_len; i++) {
4160: if (sscanf(data + 2 * i, "%2x", &value) != 1)
4161: fatal("x11_request_forwarding: bad "
4162: "authentication data: %.100s", data);
4163: if (i % 4 == 0)
4164: rnd = arc4random();
4165: x11_saved_data[i] = value;
4166: x11_fake_data[i] = rnd & 0xff;
4167: rnd >>= 8;
4168: }
4169: x11_saved_data_len = data_len;
4170: x11_fake_data_len = data_len;
1.25 markus 4171: }
4172:
4173: /* Convert the fake data into hex. */
1.219 djm 4174: new_data = tohex(x11_fake_data, data_len);
1.25 markus 4175:
4176: /* Send the request packet. */
1.51 markus 4177: if (compat20) {
1.311 djm 4178: channel_request_start(client_session_id, "x11-req", want_reply);
1.51 markus 4179: packet_put_char(0); /* XXX bool single connection */
4180: } else {
4181: packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
4182: }
4183: packet_put_cstring(proto);
4184: packet_put_cstring(new_data);
1.25 markus 4185: packet_put_int(screen_number);
4186: packet_send();
4187: packet_write_wait();
1.321 djm 4188: free(new_data);
1.1 deraadt 4189: }
4190:
1.121 markus 4191:
4192: /* -- agent forwarding */
4193:
1.1 deraadt 4194: /* Sends a message to the server to request authentication fd forwarding. */
4195:
1.49 markus 4196: void
1.142 itojun 4197: auth_request_forwarding(void)
1.1 deraadt 4198: {
1.25 markus 4199: packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
4200: packet_send();
4201: packet_write_wait();
1.1 deraadt 4202: }
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