Annotation of src/usr.bin/ssh/channels.c, Revision 1.408
1.408 ! mbuhl 1: /* $OpenBSD: channels.c,v 1.407 2021/05/19 01:24:05 djm Exp $ */
1.1 deraadt 2: /*
1.26 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * This file contains functions for generic socket connection forwarding.
7: * There is also code for initiating connection forwarding for X11 connections,
8: * arbitrary tcp/ip connections, and the authentication agent connection.
1.49 markus 9: *
1.67 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
1.44 markus 16: * SSH2 support added by Markus Friedl.
1.156 markus 17: * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
1.67 deraadt 18: * Copyright (c) 1999 Dug Song. All rights reserved.
19: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
20: *
21: * Redistribution and use in source and binary forms, with or without
22: * modification, are permitted provided that the following conditions
23: * are met:
24: * 1. Redistributions of source code must retain the above copyright
25: * notice, this list of conditions and the following disclaimer.
26: * 2. Redistributions in binary form must reproduce the above copyright
27: * notice, this list of conditions and the following disclaimer in the
28: * documentation and/or other materials provided with the distribution.
29: *
30: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.26 deraadt 40: */
1.1 deraadt 41:
1.265 deraadt 42: #include <sys/types.h>
1.336 millert 43: #include <sys/stat.h>
1.234 stevesk 44: #include <sys/ioctl.h>
1.235 stevesk 45: #include <sys/un.h>
1.251 stevesk 46: #include <sys/socket.h>
1.261 stevesk 47: #include <sys/time.h>
1.275 djm 48: #include <sys/queue.h>
1.251 stevesk 49:
50: #include <netinet/in.h>
51: #include <arpa/inet.h>
1.233 stevesk 52:
1.254 stevesk 53: #include <errno.h>
1.298 dtucker 54: #include <fcntl.h>
1.367 djm 55: #include <limits.h>
1.255 stevesk 56: #include <netdb.h>
1.367 djm 57: #include <stdarg.h>
1.341 millert 58: #include <stdint.h>
1.263 stevesk 59: #include <stdio.h>
1.262 stevesk 60: #include <stdlib.h>
1.260 stevesk 61: #include <string.h>
1.233 stevesk 62: #include <termios.h>
1.256 stevesk 63: #include <unistd.h>
1.1 deraadt 64:
1.265 deraadt 65: #include "xmalloc.h"
1.1 deraadt 66: #include "ssh.h"
1.82 markus 67: #include "ssh2.h"
1.354 markus 68: #include "ssherr.h"
1.367 djm 69: #include "sshbuf.h"
1.1 deraadt 70: #include "packet.h"
1.82 markus 71: #include "log.h"
72: #include "misc.h"
1.14 markus 73: #include "channels.h"
74: #include "compat.h"
1.82 markus 75: #include "canohost.h"
1.383 markus 76: #include "sshkey.h"
1.64 markus 77: #include "authfd.h"
1.147 stevesk 78: #include "pathnames.h"
1.381 djm 79: #include "match.h"
1.388 djm 80:
1.367 djm 81: /* -- agent forwarding */
82: #define NUM_SOCKS 10
1.12 markus 83:
1.367 djm 84: /* -- tcp forwarding */
85: /* special-case port number meaning allow any port */
86: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 87:
1.367 djm 88: /* special-case wildcard meaning allow any host */
89: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 90:
1.367 djm 91: /* -- X11 forwarding */
92: /* Maximum number of fake X11 displays to try. */
93: #define MAX_DISPLAYS 1000
1.1 deraadt 94:
1.381 djm 95: /* Per-channel callback for pre/post select() actions */
96: typedef void chan_fn(struct ssh *, Channel *c,
97: fd_set *readset, fd_set *writeset);
98:
1.27 markus 99: /*
100: * Data structure for storing which hosts are permitted for forward requests.
101: * The local sides of any remote forwards are stored in this array to prevent
102: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
103: * network (which might be behind a firewall).
104: */
1.336 millert 105: /* XXX: streamlocal wants a path instead of host:port */
106: /* Overload host_to_connect; we could just make this match Forward */
107: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 108: struct permission {
1.41 markus 109: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 110: int port_to_connect; /* Connect to 'port'. */
1.333 markus 111: char *listen_host; /* Remote side should listen address. */
1.336 millert 112: char *listen_path; /* Remote side should listen path. */
113: int listen_port; /* Remote side should listen port. */
1.354 markus 114: Channel *downstream; /* Downstream mux*/
1.381 djm 115: };
116:
117: /*
118: * Stores the forwarding permission state for a single direction (local or
119: * remote).
120: */
121: struct permission_set {
122: /*
123: * List of all local permitted host/port pairs to allow for the
124: * user.
125: */
126: u_int num_permitted_user;
127: struct permission *permitted_user;
1.1 deraadt 128:
1.381 djm 129: /*
130: * List of all permitted host/port pairs to allow for the admin.
131: */
132: u_int num_permitted_admin;
133: struct permission *permitted_admin;
134:
135: /*
136: * If this is true, all opens/listens are permitted. This is the
137: * case on the server on which we have to trust the client anyway,
138: * and the user could do anything after logging in.
139: */
140: int all_permitted;
141: };
1.121 markus 142:
1.367 djm 143: /* Master structure for channels state */
144: struct ssh_channels {
145: /*
146: * Pointer to an array containing all allocated channels. The array
147: * is dynamically extended as needed.
148: */
149: Channel **channels;
1.257 dtucker 150:
1.367 djm 151: /*
152: * Size of the channel array. All slots of the array must always be
153: * initialized (at least the type field); unused slots set to NULL
154: */
155: u_int channels_alloc;
1.257 dtucker 156:
1.367 djm 157: /*
158: * Maximum file descriptor value used in any of the channels. This is
159: * updated in channel_new.
160: */
161: int channel_max_fd;
1.257 dtucker 162:
1.367 djm 163: /*
164: * 'channel_pre*' are called just before select() to add any bits
165: * relevant to channels in the select bitmasks.
166: *
167: * 'channel_post*': perform any appropriate operations for
168: * channels which have events pending.
169: */
170: chan_fn **channel_pre;
171: chan_fn **channel_post;
1.314 dtucker 172:
1.367 djm 173: /* -- tcp forwarding */
1.381 djm 174: struct permission_set local_perms;
175: struct permission_set remote_perms;
1.219 djm 176:
1.367 djm 177: /* -- X11 forwarding */
1.121 markus 178:
1.367 djm 179: /* Saved X11 local (client) display. */
180: char *x11_saved_display;
1.121 markus 181:
1.367 djm 182: /* Saved X11 authentication protocol name. */
183: char *x11_saved_proto;
1.347 djm 184:
1.367 djm 185: /* Saved X11 authentication data. This is the real data. */
186: char *x11_saved_data;
187: u_int x11_saved_data_len;
1.121 markus 188:
1.367 djm 189: /* Deadline after which all X11 connections are refused */
190: u_int x11_refuse_time;
1.121 markus 191:
1.367 djm 192: /*
193: * Fake X11 authentication data. This is what the server will be
194: * sending us; we should replace any occurrences of this by the
195: * real data.
196: */
197: u_char *x11_fake_data;
198: u_int x11_fake_data_len;
1.121 markus 199:
1.367 djm 200: /* AF_UNSPEC or AF_INET or AF_INET6 */
201: int IPv4or6;
202: };
1.1 deraadt 203:
1.121 markus 204: /* helper */
1.367 djm 205: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 206: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 207:
1.276 djm 208: /* non-blocking connect helpers */
209: static int connect_next(struct channel_connect *);
210: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 211: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
212: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 213:
1.367 djm 214: /* Setup helper */
215: static void channel_handler_init(struct ssh_channels *sc);
216:
1.121 markus 217: /* -- channel core */
1.41 markus 218:
1.367 djm 219: void
220: channel_init_channels(struct ssh *ssh)
221: {
222: struct ssh_channels *sc;
223:
1.387 djm 224: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.403 djm 225: fatal_f("allocation failed");
1.367 djm 226: sc->channels_alloc = 10;
227: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
228: sc->IPv4or6 = AF_UNSPEC;
229: channel_handler_init(sc);
230:
231: ssh->chanctxt = sc;
232: }
233:
1.41 markus 234: Channel *
1.367 djm 235: channel_by_id(struct ssh *ssh, int id)
1.41 markus 236: {
237: Channel *c;
1.113 markus 238:
1.367 djm 239: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
1.403 djm 240: logit_f("%d: bad id", id);
1.41 markus 241: return NULL;
242: }
1.367 djm 243: c = ssh->chanctxt->channels[id];
1.113 markus 244: if (c == NULL) {
1.403 djm 245: logit_f("%d: bad id: channel free", id);
1.41 markus 246: return NULL;
247: }
248: return c;
1.55 markus 249: }
250:
1.354 markus 251: Channel *
1.368 djm 252: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 253: {
254: Channel *c;
255: u_int i;
256:
1.367 djm 257: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
258: c = ssh->chanctxt->channels[i];
1.368 djm 259: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 260: return c;
261: }
262: return NULL;
263: }
264:
1.27 markus 265: /*
1.229 markus 266: * Returns the channel if it is allowed to receive protocol messages.
267: * Private channels, like listening sockets, may not receive messages.
268: */
269: Channel *
1.367 djm 270: channel_lookup(struct ssh *ssh, int id)
1.229 markus 271: {
272: Channel *c;
273:
1.367 djm 274: if ((c = channel_by_id(ssh, id)) == NULL)
275: return NULL;
1.229 markus 276:
1.237 deraadt 277: switch (c->type) {
1.229 markus 278: case SSH_CHANNEL_X11_OPEN:
279: case SSH_CHANNEL_LARVAL:
280: case SSH_CHANNEL_CONNECTING:
281: case SSH_CHANNEL_DYNAMIC:
1.372 markus 282: case SSH_CHANNEL_RDYNAMIC_OPEN:
283: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 284: case SSH_CHANNEL_OPENING:
285: case SSH_CHANNEL_OPEN:
1.323 dtucker 286: case SSH_CHANNEL_ABANDONED:
1.354 markus 287: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 288: return c;
1.229 markus 289: }
290: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 291: return NULL;
1.229 markus 292: }
293:
294: /*
1.55 markus 295: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 296: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 297: */
1.127 itojun 298: static void
1.367 djm 299: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 300: int extusage, int nonblock, int is_tty)
1.1 deraadt 301: {
1.367 djm 302: struct ssh_channels *sc = ssh->chanctxt;
303:
1.25 markus 304: /* Update the maximum file descriptor value. */
1.367 djm 305: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, rfd);
306: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, wfd);
307: sc->channel_max_fd = MAXIMUM(sc->channel_max_fd, efd);
1.84 markus 308:
1.298 dtucker 309: if (rfd != -1)
310: fcntl(rfd, F_SETFD, FD_CLOEXEC);
311: if (wfd != -1 && wfd != rfd)
312: fcntl(wfd, F_SETFD, FD_CLOEXEC);
313: if (efd != -1 && efd != rfd && efd != wfd)
314: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 315:
1.52 markus 316: c->rfd = rfd;
317: c->wfd = wfd;
318: c->sock = (rfd == wfd) ? rfd : -1;
319: c->efd = efd;
320: c->extended_usage = extusage;
1.71 markus 321:
1.282 dtucker 322: if ((c->isatty = is_tty) != 0)
1.194 markus 323: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 324:
1.71 markus 325: /* enable nonblocking mode */
1.407 djm 326: c->restore_block = 0;
327: if (nonblock == CHANNEL_NONBLOCK_STDIO) {
328: /*
329: * Special handling for stdio file descriptors: do not set
330: * non-blocking mode if they are TTYs. Otherwise prepare to
331: * restore their blocking state on exit to avoid interfering
332: * with other programs that follow.
333: */
334: if (rfd != -1 && !isatty(rfd) && fcntl(rfd, F_GETFL) == 0) {
335: c->restore_block |= CHANNEL_RESTORE_RFD;
336: set_nonblock(rfd);
337: }
338: if (wfd != -1 && !isatty(wfd) && fcntl(wfd, F_GETFL) == 0) {
339: c->restore_block |= CHANNEL_RESTORE_WFD;
340: set_nonblock(wfd);
341: }
342: if (efd != -1 && !isatty(efd) && fcntl(efd, F_GETFL) == 0) {
343: c->restore_block |= CHANNEL_RESTORE_EFD;
344: set_nonblock(efd);
345: }
346: } else if (nonblock) {
1.71 markus 347: if (rfd != -1)
348: set_nonblock(rfd);
349: if (wfd != -1)
350: set_nonblock(wfd);
351: if (efd != -1)
352: set_nonblock(efd);
353: }
1.52 markus 354: }
355:
356: /*
357: * Allocate a new channel object and set its type and socket. This will cause
358: * remote_name to be freed.
359: */
1.113 markus 360: Channel *
1.367 djm 361: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 362: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 363: {
1.367 djm 364: struct ssh_channels *sc = ssh->chanctxt;
365: u_int i, found;
1.52 markus 366: Channel *c;
1.402 djm 367: int r;
1.25 markus 368:
369: /* Try to find a free slot where to put the new channel. */
1.367 djm 370: for (i = 0; i < sc->channels_alloc; i++) {
371: if (sc->channels[i] == NULL) {
1.25 markus 372: /* Found a free slot. */
1.367 djm 373: found = i;
1.25 markus 374: break;
375: }
1.367 djm 376: }
377: if (i >= sc->channels_alloc) {
378: /*
379: * There are no free slots. Take last+1 slot and expand
380: * the array.
381: */
382: found = sc->channels_alloc;
383: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
1.403 djm 384: fatal_f("internal error: channels_alloc %d too big",
385: sc->channels_alloc);
1.367 djm 386: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
387: sc->channels_alloc + 10, sizeof(*sc->channels));
388: sc->channels_alloc += 10;
389: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 390: }
1.113 markus 391: /* Initialize and return new channel. */
1.367 djm 392: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
393: if ((c->input = sshbuf_new()) == NULL ||
394: (c->output = sshbuf_new()) == NULL ||
395: (c->extended = sshbuf_new()) == NULL)
1.403 djm 396: fatal_f("sshbuf_new failed");
1.402 djm 397: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
1.403 djm 398: fatal_fr(r, "sshbuf_set_max_size");
1.159 markus 399: c->ostate = CHAN_OUTPUT_OPEN;
400: c->istate = CHAN_INPUT_OPEN;
1.367 djm 401: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 402: c->self = found;
403: c->type = type;
1.41 markus 404: c->ctype = ctype;
1.51 markus 405: c->local_window = window;
406: c->local_window_max = window;
407: c->local_maxpacket = maxpack;
1.190 markus 408: c->remote_name = xstrdup(remote_name);
1.302 djm 409: c->ctl_chan = -1;
1.299 markus 410: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 411: TAILQ_INIT(&c->status_confirms);
1.25 markus 412: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 413: return c;
1.1 deraadt 414: }
1.52 markus 415:
1.367 djm 416: static void
417: channel_find_maxfd(struct ssh_channels *sc)
1.132 markus 418: {
1.209 avsm 419: u_int i;
420: int max = 0;
1.132 markus 421: Channel *c;
422:
1.367 djm 423: for (i = 0; i < sc->channels_alloc; i++) {
424: c = sc->channels[i];
1.132 markus 425: if (c != NULL) {
1.352 deraadt 426: max = MAXIMUM(max, c->rfd);
427: max = MAXIMUM(max, c->wfd);
428: max = MAXIMUM(max, c->efd);
1.132 markus 429: }
430: }
1.367 djm 431: sc->channel_max_fd = max;
1.132 markus 432: }
433:
434: int
1.407 djm 435: channel_close_fd(struct ssh *ssh, Channel *c, int *fdp)
1.132 markus 436: {
1.367 djm 437: struct ssh_channels *sc = ssh->chanctxt;
1.407 djm 438: int ret, fd = *fdp;
1.132 markus 439:
1.407 djm 440: if (fd == -1)
441: return 0;
442:
443: if ((*fdp == c->rfd && (c->restore_block & CHANNEL_RESTORE_RFD) != 0) ||
444: (*fdp == c->wfd && (c->restore_block & CHANNEL_RESTORE_WFD) != 0) ||
445: (*fdp == c->efd && (c->restore_block & CHANNEL_RESTORE_EFD) != 0))
446: (void)fcntl(*fdp, F_SETFL, 0); /* restore blocking */
447:
448: ret = close(fd);
449: *fdp = -1;
450: if (fd == sc->channel_max_fd)
451: channel_find_maxfd(sc);
1.132 markus 452: return ret;
453: }
454:
1.52 markus 455: /* Close all channel fd/socket. */
1.127 itojun 456: static void
1.367 djm 457: channel_close_fds(struct ssh *ssh, Channel *c)
458: {
1.379 tb 459: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
460:
1.407 djm 461: channel_close_fd(ssh, c, &c->sock);
1.379 tb 462: if (rfd != sock)
1.407 djm 463: channel_close_fd(ssh, c, &c->rfd);
1.379 tb 464: if (wfd != sock && wfd != rfd)
1.407 djm 465: channel_close_fd(ssh, c, &c->wfd);
1.379 tb 466: if (efd != sock && efd != rfd && efd != wfd)
1.407 djm 467: channel_close_fd(ssh, c, &c->efd);
1.367 djm 468: }
469:
470: static void
1.381 djm 471: fwd_perm_clear(struct permission *perm)
1.52 markus 472: {
1.381 djm 473: free(perm->host_to_connect);
474: free(perm->listen_host);
475: free(perm->listen_path);
1.398 dtucker 476: memset(perm, 0, sizeof(*perm));
1.367 djm 477: }
478:
1.381 djm 479: /* Returns an printable name for the specified forwarding permission list */
480: static const char *
481: fwd_ident(int who, int where)
482: {
483: if (who == FORWARD_ADM) {
484: if (where == FORWARD_LOCAL)
485: return "admin local";
486: else if (where == FORWARD_REMOTE)
487: return "admin remote";
488: } else if (who == FORWARD_USER) {
489: if (where == FORWARD_LOCAL)
490: return "user local";
491: else if (where == FORWARD_REMOTE)
492: return "user remote";
493: }
494: fatal("Unknown forward permission list %d/%d", who, where);
495: }
496:
497: /* Returns the forwarding permission list for the specified direction */
498: static struct permission_set *
499: permission_set_get(struct ssh *ssh, int where)
500: {
501: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 502:
1.381 djm 503: switch (where) {
504: case FORWARD_LOCAL:
505: return &sc->local_perms;
506: break;
507: case FORWARD_REMOTE:
508: return &sc->remote_perms;
509: break;
510: default:
1.403 djm 511: fatal_f("invalid forwarding direction %d", where);
1.381 djm 512: }
513: }
514:
1.392 dtucker 515: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 516: static void
517: permission_set_get_array(struct ssh *ssh, int who, int where,
518: struct permission ***permpp, u_int **npermpp)
519: {
520: struct permission_set *pset = permission_set_get(ssh, where);
521:
522: switch (who) {
523: case FORWARD_USER:
524: *permpp = &pset->permitted_user;
525: *npermpp = &pset->num_permitted_user;
526: break;
527: case FORWARD_ADM:
528: *permpp = &pset->permitted_admin;
529: *npermpp = &pset->num_permitted_admin;
530: break;
531: default:
1.403 djm 532: fatal_f("invalid forwarding client %d", who);
1.381 djm 533: }
534: }
535:
536: /* Adds an entry to the spcified forwarding list */
1.367 djm 537: static int
1.381 djm 538: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 539: const char *host_to_connect, int port_to_connect,
540: const char *listen_host, const char *listen_path, int listen_port,
541: Channel *downstream)
542: {
1.381 djm 543: struct permission **permp;
544: u_int n, *npermp;
1.367 djm 545:
1.381 djm 546: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 547:
1.381 djm 548: if (*npermp >= INT_MAX)
1.403 djm 549: fatal_f("%s overflow", fwd_ident(who, where));
1.367 djm 550:
1.381 djm 551: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
552: n = (*npermp)++;
1.367 djm 553: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 554: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
555: (*permp)[n].port_to_connect = port_to_connect;
556: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
557: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
558: (*permp)[n].listen_port = listen_port;
559: (*permp)[n].downstream = downstream;
1.367 djm 560: #undef MAYBE_DUP
561: return (int)n;
562: }
563:
564: static void
565: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
566: {
567: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 568: struct permission_set *pset = &sc->local_perms;
569: struct permission *perm;
1.367 djm 570: int r;
571: u_int i;
572:
1.381 djm 573: for (i = 0; i < pset->num_permitted_user; i++) {
574: perm = &pset->permitted_user[i];
575: if (perm->downstream != c)
1.367 djm 576: continue;
577:
578: /* cancel on the server, since mux client is gone */
579: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 580: c->self, perm->listen_host, perm->listen_port);
1.367 djm 581: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
582: (r = sshpkt_put_cstring(ssh,
583: "cancel-tcpip-forward")) != 0 ||
584: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
585: (r = sshpkt_put_cstring(ssh,
1.381 djm 586: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
587: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 588: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 589: fatal_fr(r, "channel %i", c->self);
1.367 djm 590: }
1.381 djm 591: fwd_perm_clear(perm); /* unregister */
1.367 djm 592: }
1.121 markus 593: }
594:
595: /* Free the channel and close its fd/socket. */
596: void
1.367 djm 597: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 598: {
1.367 djm 599: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 600: char *s;
1.209 avsm 601: u_int i, n;
1.354 markus 602: Channel *other;
1.275 djm 603: struct channel_confirm *cc;
1.121 markus 604:
1.367 djm 605: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
606: if ((other = sc->channels[i]) == NULL)
607: continue;
608: n++;
609: /* detach from mux client and prepare for closing */
610: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
611: other->type == SSH_CHANNEL_MUX_PROXY &&
612: other->mux_ctx == c) {
613: other->mux_ctx = NULL;
614: other->type = SSH_CHANNEL_OPEN;
615: other->istate = CHAN_INPUT_CLOSED;
616: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 617: }
618: }
1.209 avsm 619: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 620: c->remote_name ? c->remote_name : "???", n);
621:
1.408 ! mbuhl 622: if (c->type == SSH_CHANNEL_MUX_CLIENT) {
1.367 djm 623: mux_remove_remote_forwardings(ssh, c);
1.408 ! mbuhl 624: free(c->mux_ctx);
! 625: c->mux_ctx = NULL;
! 626: } else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
1.401 djm 627: free(c->mux_ctx);
628: c->mux_ctx = NULL;
629: }
1.354 markus 630:
1.384 markus 631: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
632: s = channel_open_message(ssh);
633: debug3("channel %d: status: %s", c->self, s);
634: free(s);
635: }
1.121 markus 636:
1.367 djm 637: channel_close_fds(ssh, c);
638: sshbuf_free(c->input);
639: sshbuf_free(c->output);
640: sshbuf_free(c->extended);
641: c->input = c->output = c->extended = NULL;
1.321 djm 642: free(c->remote_name);
643: c->remote_name = NULL;
644: free(c->path);
645: c->path = NULL;
646: free(c->listening_addr);
647: c->listening_addr = NULL;
1.275 djm 648: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
649: if (cc->abandon_cb != NULL)
1.367 djm 650: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 651: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 652: freezero(cc, sizeof(*cc));
1.275 djm 653: }
1.280 djm 654: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 655: c->filter_cleanup(ssh, c->self, c->filter_ctx);
656: sc->channels[c->self] = NULL;
1.396 jsg 657: freezero(c, sizeof(*c));
1.121 markus 658: }
659:
660: void
1.367 djm 661: channel_free_all(struct ssh *ssh)
1.121 markus 662: {
1.209 avsm 663: u_int i;
1.390 dtucker 664: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 665:
1.390 dtucker 666: for (i = 0; i < sc->channels_alloc; i++)
667: if (sc->channels[i] != NULL)
668: channel_free(ssh, sc->channels[i]);
669:
670: free(sc->channels);
671: sc->channels = NULL;
672: sc->channels_alloc = 0;
673: sc->channel_max_fd = 0;
674:
675: free(sc->x11_saved_display);
676: sc->x11_saved_display = NULL;
677:
678: free(sc->x11_saved_proto);
679: sc->x11_saved_proto = NULL;
680:
681: free(sc->x11_saved_data);
682: sc->x11_saved_data = NULL;
683: sc->x11_saved_data_len = 0;
684:
685: free(sc->x11_fake_data);
686: sc->x11_fake_data = NULL;
687: sc->x11_fake_data_len = 0;
1.131 markus 688: }
689:
1.121 markus 690: /*
691: * Closes the sockets/fds of all channels. This is used to close extra file
692: * descriptors after a fork.
693: */
694: void
1.367 djm 695: channel_close_all(struct ssh *ssh)
1.121 markus 696: {
1.209 avsm 697: u_int i;
1.121 markus 698:
1.367 djm 699: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
700: if (ssh->chanctxt->channels[i] != NULL)
701: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 702: }
703:
704: /*
1.131 markus 705: * Stop listening to channels.
706: */
707: void
1.367 djm 708: channel_stop_listening(struct ssh *ssh)
1.131 markus 709: {
1.209 avsm 710: u_int i;
1.131 markus 711: Channel *c;
712:
1.367 djm 713: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
714: c = ssh->chanctxt->channels[i];
1.131 markus 715: if (c != NULL) {
716: switch (c->type) {
717: case SSH_CHANNEL_AUTH_SOCKET:
718: case SSH_CHANNEL_PORT_LISTENER:
719: case SSH_CHANNEL_RPORT_LISTENER:
720: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 721: case SSH_CHANNEL_UNIX_LISTENER:
722: case SSH_CHANNEL_RUNIX_LISTENER:
1.407 djm 723: channel_close_fd(ssh, c, &c->sock);
1.367 djm 724: channel_free(ssh, c);
1.131 markus 725: break;
726: }
727: }
728: }
729: }
730:
731: /*
1.121 markus 732: * Returns true if no channel has too much buffered data, and false if one or
733: * more channel is overfull.
734: */
735: int
1.367 djm 736: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 737: {
738: u_int i;
1.367 djm 739: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 740: Channel *c;
741:
1.367 djm 742: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
743: c = ssh->chanctxt->channels[i];
744: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
745: continue;
746: if (sshbuf_len(c->output) > maxsize) {
747: debug2("channel %d: big output buffer %zu > %u",
748: c->self, sshbuf_len(c->output), maxsize);
749: return 0;
1.121 markus 750: }
751: }
752: return 1;
753: }
754:
755: /* Returns true if any channel is still open. */
756: int
1.367 djm 757: channel_still_open(struct ssh *ssh)
1.121 markus 758: {
1.209 avsm 759: u_int i;
1.121 markus 760: Channel *c;
761:
1.367 djm 762: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
763: c = ssh->chanctxt->channels[i];
1.121 markus 764: if (c == NULL)
765: continue;
766: switch (c->type) {
767: case SSH_CHANNEL_X11_LISTENER:
768: case SSH_CHANNEL_PORT_LISTENER:
769: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 770: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 771: case SSH_CHANNEL_CLOSED:
772: case SSH_CHANNEL_AUTH_SOCKET:
773: case SSH_CHANNEL_DYNAMIC:
1.372 markus 774: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 775: case SSH_CHANNEL_CONNECTING:
776: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 777: case SSH_CHANNEL_ABANDONED:
1.336 millert 778: case SSH_CHANNEL_UNIX_LISTENER:
779: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 780: continue;
781: case SSH_CHANNEL_LARVAL:
782: continue;
783: case SSH_CHANNEL_OPENING:
784: case SSH_CHANNEL_OPEN:
1.372 markus 785: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 786: case SSH_CHANNEL_X11_OPEN:
1.302 djm 787: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 788: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 789: return 1;
790: default:
1.403 djm 791: fatal_f("bad channel type %d", c->type);
1.121 markus 792: /* NOTREACHED */
793: }
794: }
795: return 0;
796: }
797:
798: /* Returns the id of an open channel suitable for keepaliving */
799: int
1.367 djm 800: channel_find_open(struct ssh *ssh)
1.121 markus 801: {
1.209 avsm 802: u_int i;
1.121 markus 803: Channel *c;
804:
1.367 djm 805: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
806: c = ssh->chanctxt->channels[i];
1.368 djm 807: if (c == NULL || !c->have_remote_id)
1.121 markus 808: continue;
809: switch (c->type) {
810: case SSH_CHANNEL_CLOSED:
811: case SSH_CHANNEL_DYNAMIC:
1.372 markus 812: case SSH_CHANNEL_RDYNAMIC_OPEN:
813: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 814: case SSH_CHANNEL_X11_LISTENER:
815: case SSH_CHANNEL_PORT_LISTENER:
816: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 817: case SSH_CHANNEL_MUX_LISTENER:
818: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 819: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 820: case SSH_CHANNEL_OPENING:
821: case SSH_CHANNEL_CONNECTING:
822: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 823: case SSH_CHANNEL_ABANDONED:
1.336 millert 824: case SSH_CHANNEL_UNIX_LISTENER:
825: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 826: continue;
827: case SSH_CHANNEL_LARVAL:
828: case SSH_CHANNEL_AUTH_SOCKET:
829: case SSH_CHANNEL_OPEN:
830: case SSH_CHANNEL_X11_OPEN:
831: return i;
832: default:
1.403 djm 833: fatal_f("bad channel type %d", c->type);
1.121 markus 834: /* NOTREACHED */
835: }
836: }
837: return -1;
838: }
839:
1.385 djm 840: /* Returns the state of the channel's extended usage flag */
841: const char *
842: channel_format_extended_usage(const Channel *c)
843: {
844: if (c->efd == -1)
845: return "closed";
846:
847: switch (c->extended_usage) {
848: case CHAN_EXTENDED_WRITE:
849: return "write";
850: case CHAN_EXTENDED_READ:
851: return "read";
852: case CHAN_EXTENDED_IGNORE:
853: return "ignore";
854: default:
855: return "UNKNOWN";
856: }
857: }
858:
1.386 djm 859: static char *
860: channel_format_status(const Channel *c)
861: {
862: char *ret = NULL;
863:
864: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
865: "fd %d/%d/%d sock %d cc %d",
866: c->type,
867: c->have_remote_id ? "r" : "nr", c->remote_id,
868: c->istate, sshbuf_len(c->input),
869: c->ostate, sshbuf_len(c->output),
870: channel_format_extended_usage(c), sshbuf_len(c->extended),
871: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan);
872: return ret;
873: }
874:
1.121 markus 875: /*
876: * Returns a message describing the currently open forwarded connections,
877: * suitable for sending to the client. The message contains crlf pairs for
878: * newlines.
879: */
880: char *
1.367 djm 881: channel_open_message(struct ssh *ssh)
1.121 markus 882: {
1.367 djm 883: struct sshbuf *buf;
1.121 markus 884: Channel *c;
1.209 avsm 885: u_int i;
1.367 djm 886: int r;
1.386 djm 887: char *cp, *ret;
1.121 markus 888:
1.367 djm 889: if ((buf = sshbuf_new()) == NULL)
1.403 djm 890: fatal_f("sshbuf_new");
1.367 djm 891: if ((r = sshbuf_putf(buf,
892: "The following connections are open:\r\n")) != 0)
1.403 djm 893: fatal_fr(r, "sshbuf_putf");
1.367 djm 894: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
895: c = ssh->chanctxt->channels[i];
1.121 markus 896: if (c == NULL)
897: continue;
898: switch (c->type) {
899: case SSH_CHANNEL_X11_LISTENER:
900: case SSH_CHANNEL_PORT_LISTENER:
901: case SSH_CHANNEL_RPORT_LISTENER:
902: case SSH_CHANNEL_CLOSED:
903: case SSH_CHANNEL_AUTH_SOCKET:
904: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 905: case SSH_CHANNEL_ABANDONED:
1.302 djm 906: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 907: case SSH_CHANNEL_UNIX_LISTENER:
908: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 909: continue;
910: case SSH_CHANNEL_LARVAL:
911: case SSH_CHANNEL_OPENING:
912: case SSH_CHANNEL_CONNECTING:
913: case SSH_CHANNEL_DYNAMIC:
1.372 markus 914: case SSH_CHANNEL_RDYNAMIC_OPEN:
915: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 916: case SSH_CHANNEL_OPEN:
917: case SSH_CHANNEL_X11_OPEN:
1.354 markus 918: case SSH_CHANNEL_MUX_PROXY:
919: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 920: cp = channel_format_status(c);
921: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
922: c->self, c->remote_name, cp)) != 0) {
923: free(cp);
1.403 djm 924: fatal_fr(r, "sshbuf_putf");
1.386 djm 925: }
926: free(cp);
1.121 markus 927: continue;
928: default:
1.403 djm 929: fatal_f("bad channel type %d", c->type);
1.121 markus 930: /* NOTREACHED */
931: }
932: }
1.367 djm 933: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 934: fatal_f("sshbuf_dup_string");
1.367 djm 935: sshbuf_free(buf);
936: return ret;
937: }
938:
939: static void
940: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
941: {
942: int r;
943:
944: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
945: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
946: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
947: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
948: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 949: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 950: }
1.121 markus 951: }
952:
953: void
1.367 djm 954: channel_send_open(struct ssh *ssh, int id)
1.121 markus 955: {
1.367 djm 956: Channel *c = channel_lookup(ssh, id);
957: int r;
1.180 deraadt 958:
1.121 markus 959: if (c == NULL) {
1.188 itojun 960: logit("channel_send_open: %d: bad id", id);
1.121 markus 961: return;
962: }
1.184 markus 963: debug2("channel %d: send open", id);
1.367 djm 964: open_preamble(ssh, __func__, c, c->ctype);
965: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 966: fatal_fr(r, "channel %i", c->self);
1.121 markus 967: }
968:
969: void
1.367 djm 970: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 971: {
1.367 djm 972: Channel *c = channel_lookup(ssh, id);
973: int r;
1.180 deraadt 974:
1.121 markus 975: if (c == NULL) {
1.403 djm 976: logit_f("%d: unknown channel id", id);
1.121 markus 977: return;
978: }
1.368 djm 979: if (!c->have_remote_id)
1.403 djm 980: fatal_f("channel %d: no remote id", c->self);
1.368 djm 981:
1.204 djm 982: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 983: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
984: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
985: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
986: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 987: fatal_fr(r, "channel %i", c->self);
1.367 djm 988: }
1.121 markus 989: }
1.241 deraadt 990:
1.121 markus 991: void
1.367 djm 992: channel_register_status_confirm(struct ssh *ssh, int id,
993: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 994: {
995: struct channel_confirm *cc;
996: Channel *c;
997:
1.367 djm 998: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 999: fatal_f("%d: bad id", id);
1.275 djm 1000:
1.327 djm 1001: cc = xcalloc(1, sizeof(*cc));
1.275 djm 1002: cc->cb = cb;
1003: cc->abandon_cb = abandon_cb;
1004: cc->ctx = ctx;
1005: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
1006: }
1007:
1008: void
1.367 djm 1009: channel_register_open_confirm(struct ssh *ssh, int id,
1010: channel_open_fn *fn, void *ctx)
1.121 markus 1011: {
1.367 djm 1012: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1013:
1.121 markus 1014: if (c == NULL) {
1.403 djm 1015: logit_f("%d: bad id", id);
1.121 markus 1016: return;
1017: }
1.275 djm 1018: c->open_confirm = fn;
1019: c->open_confirm_ctx = ctx;
1.121 markus 1020: }
1.241 deraadt 1021:
1.121 markus 1022: void
1.367 djm 1023: channel_register_cleanup(struct ssh *ssh, int id,
1024: channel_callback_fn *fn, int do_close)
1.121 markus 1025: {
1.367 djm 1026: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1027:
1.121 markus 1028: if (c == NULL) {
1.403 djm 1029: logit_f("%d: bad id", id);
1.121 markus 1030: return;
1031: }
1.131 markus 1032: c->detach_user = fn;
1.225 djm 1033: c->detach_close = do_close;
1.121 markus 1034: }
1.241 deraadt 1035:
1.121 markus 1036: void
1.367 djm 1037: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1038: {
1.367 djm 1039: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1040:
1.121 markus 1041: if (c == NULL) {
1.403 djm 1042: logit_f("%d: bad id", id);
1.121 markus 1043: return;
1.52 markus 1044: }
1.131 markus 1045: c->detach_user = NULL;
1.225 djm 1046: c->detach_close = 0;
1.121 markus 1047: }
1.241 deraadt 1048:
1.121 markus 1049: void
1.367 djm 1050: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1051: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1052: {
1.367 djm 1053: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1054:
1.121 markus 1055: if (c == NULL) {
1.403 djm 1056: logit_f("%d: bad id", id);
1.121 markus 1057: return;
1.52 markus 1058: }
1.231 reyk 1059: c->input_filter = ifn;
1060: c->output_filter = ofn;
1.279 djm 1061: c->filter_ctx = ctx;
1.280 djm 1062: c->filter_cleanup = cfn;
1.52 markus 1063: }
1064:
1.49 markus 1065: void
1.367 djm 1066: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1067: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1068: {
1.367 djm 1069: Channel *c = channel_lookup(ssh, id);
1070: int r;
1.180 deraadt 1071:
1.121 markus 1072: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1073: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1074: if (!c->have_remote_id)
1.403 djm 1075: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1076:
1.367 djm 1077: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1078: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1079: c->local_window = c->local_window_max = window_max;
1.367 djm 1080:
1081: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1082: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1083: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1084: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1085: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1086: }
1087:
1.127 itojun 1088: static void
1.367 djm 1089: channel_pre_listener(struct ssh *ssh, Channel *c,
1090: fd_set *readset, fd_set *writeset)
1.41 markus 1091: {
1092: FD_SET(c->sock, readset);
1093: }
1094:
1.127 itojun 1095: static void
1.367 djm 1096: channel_pre_connecting(struct ssh *ssh, Channel *c,
1097: fd_set *readset, fd_set *writeset)
1.75 markus 1098: {
1099: debug3("channel %d: waiting for connection", c->self);
1100: FD_SET(c->sock, writeset);
1101: }
1102:
1.127 itojun 1103: static void
1.367 djm 1104: channel_pre_open(struct ssh *ssh, Channel *c,
1105: fd_set *readset, fd_set *writeset)
1.41 markus 1106: {
1.44 markus 1107: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1108: c->remote_window > 0 &&
1.367 djm 1109: sshbuf_len(c->input) < c->remote_window &&
1110: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.44 markus 1111: FD_SET(c->rfd, readset);
1112: if (c->ostate == CHAN_OUTPUT_OPEN ||
1113: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1114: if (sshbuf_len(c->output) > 0) {
1.44 markus 1115: FD_SET(c->wfd, writeset);
1116: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1117: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1118: debug2("channel %d: "
1119: "obuf_empty delayed efd %d/(%zu)", c->self,
1120: c->efd, sshbuf_len(c->extended));
1.172 markus 1121: else
1.367 djm 1122: chan_obuf_empty(ssh, c);
1.44 markus 1123: }
1124: }
1125: /** XXX check close conditions, too */
1.358 djm 1126: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1127: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1128: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1129: sshbuf_len(c->extended) > 0)
1.44 markus 1130: FD_SET(c->efd, writeset);
1.306 djm 1131: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1132: (c->extended_usage == CHAN_EXTENDED_READ ||
1133: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1134: sshbuf_len(c->extended) < c->remote_window)
1.44 markus 1135: FD_SET(c->efd, readset);
1136: }
1.204 djm 1137: /* XXX: What about efd? races? */
1.44 markus 1138: }
1139:
1.41 markus 1140: /*
1141: * This is a special state for X11 authentication spoofing. An opened X11
1142: * connection (when authentication spoofing is being done) remains in this
1143: * state until the first packet has been completely read. The authentication
1144: * data in that packet is then substituted by the real data if it matches the
1145: * fake data, and the channel is put into normal mode.
1.51 markus 1146: * XXX All this happens at the client side.
1.121 markus 1147: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1148: */
1.127 itojun 1149: static int
1.367 djm 1150: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1151: {
1.367 djm 1152: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1153: u_char *ucp;
1154: u_int proto_len, data_len;
1.25 markus 1155:
1.347 djm 1156: /* Is this being called after the refusal deadline? */
1.367 djm 1157: if (sc->x11_refuse_time != 0 &&
1158: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1159: verbose("Rejected X11 connection after ForwardX11Timeout "
1160: "expired");
1161: return -1;
1162: }
1163:
1.41 markus 1164: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1165: if (sshbuf_len(b) < 12)
1.41 markus 1166: return 0;
1167:
1168: /* Parse the lengths of variable-length fields. */
1.367 djm 1169: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1170: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1171: proto_len = 256 * ucp[6] + ucp[7];
1172: data_len = 256 * ucp[8] + ucp[9];
1173: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1174: proto_len = ucp[6] + 256 * ucp[7];
1175: data_len = ucp[8] + 256 * ucp[9];
1176: } else {
1.194 markus 1177: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1178: ucp[0]);
1.41 markus 1179: return -1;
1180: }
1181:
1182: /* Check if the whole packet is in buffer. */
1.367 djm 1183: if (sshbuf_len(b) <
1.41 markus 1184: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1185: return 0;
1186:
1187: /* Check if authentication protocol matches. */
1.367 djm 1188: if (proto_len != strlen(sc->x11_saved_proto) ||
1189: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1190: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1191: return -1;
1192: }
1193: /* Check if authentication data matches our fake data. */
1.367 djm 1194: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1195: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1196: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1197: debug2("X11 auth data does not match fake data.");
1.41 markus 1198: return -1;
1199: }
1200: /* Check fake data length */
1.367 djm 1201: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1202: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1203: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1204: return -1;
1205: }
1206: /*
1207: * Received authentication protocol and data match
1208: * our fake data. Substitute the fake data with real
1209: * data.
1210: */
1211: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1212: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1213: return 1;
1214: }
1215:
1.127 itojun 1216: static void
1.367 djm 1217: channel_pre_x11_open(struct ssh *ssh, Channel *c,
1218: fd_set *readset, fd_set *writeset)
1.41 markus 1219: {
1.367 djm 1220: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1221:
1222: /* c->force_drain = 1; */
1223:
1.41 markus 1224: if (ret == 1) {
1225: c->type = SSH_CHANNEL_OPEN;
1.367 djm 1226: channel_pre_open(ssh, c, readset, writeset);
1.41 markus 1227: } else if (ret == -1) {
1.188 itojun 1228: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1229: debug2("X11 rejected %d i%d/o%d",
1230: c->self, c->istate, c->ostate);
1231: chan_read_failed(ssh, c);
1232: sshbuf_reset(c->input);
1233: chan_ibuf_empty(ssh, c);
1234: sshbuf_reset(c->output);
1235: chan_write_failed(ssh, c);
1.194 markus 1236: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1237: }
1238: }
1.25 markus 1239:
1.302 djm 1240: static void
1.367 djm 1241: channel_pre_mux_client(struct ssh *ssh,
1242: Channel *c, fd_set *readset, fd_set *writeset)
1.302 djm 1243: {
1.304 djm 1244: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1245: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.302 djm 1246: FD_SET(c->rfd, readset);
1247: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1248: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1249: sshbuf_reset(c->input);
1250: chan_ibuf_empty(ssh, c);
1.302 djm 1251: /* Start output drain. XXX just kill chan? */
1.367 djm 1252: chan_rcvd_oclose(ssh, c);
1.302 djm 1253: }
1254: if (c->ostate == CHAN_OUTPUT_OPEN ||
1255: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1256: if (sshbuf_len(c->output) > 0)
1.302 djm 1257: FD_SET(c->wfd, writeset);
1258: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1259: chan_obuf_empty(ssh, c);
1.302 djm 1260: }
1261: }
1262:
1.104 markus 1263: /* try to decode a socks4 header */
1.127 itojun 1264: static int
1.372 markus 1265: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1266: {
1.367 djm 1267: const u_char *p;
1268: char *host;
1.292 djm 1269: u_int len, have, i, found, need;
1.148 deraadt 1270: char username[256];
1.103 markus 1271: struct {
1272: u_int8_t version;
1273: u_int8_t command;
1274: u_int16_t dest_port;
1.104 markus 1275: struct in_addr dest_addr;
1.103 markus 1276: } s4_req, s4_rsp;
1.367 djm 1277: int r;
1.103 markus 1278:
1.104 markus 1279: debug2("channel %d: decode socks4", c->self);
1.109 markus 1280:
1.372 markus 1281: have = sshbuf_len(input);
1.109 markus 1282: len = sizeof(s4_req);
1283: if (have < len)
1284: return 0;
1.372 markus 1285: p = sshbuf_ptr(input);
1.292 djm 1286:
1287: need = 1;
1288: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1289: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1290: debug2("channel %d: socks4a request", c->self);
1291: /* ... and needs an extra string (the hostname) */
1292: need = 2;
1293: }
1294: /* Check for terminating NUL on the string(s) */
1.109 markus 1295: for (found = 0, i = len; i < have; i++) {
1296: if (p[i] == '\0') {
1.292 djm 1297: found++;
1298: if (found == need)
1299: break;
1.109 markus 1300: }
1301: if (i > 1024) {
1302: /* the peer is probably sending garbage */
1303: debug("channel %d: decode socks4: too long",
1304: c->self);
1305: return -1;
1306: }
1307: }
1.292 djm 1308: if (found < need)
1.109 markus 1309: return 0;
1.372 markus 1310: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1311: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1312: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1313: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1314: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1315: return -1;
1316: }
1.372 markus 1317: have = sshbuf_len(input);
1318: p = sshbuf_ptr(input);
1.364 djm 1319: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1320: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1321: return -1;
1322: }
1.103 markus 1323: len = strlen(p);
1.106 markus 1324: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1325: len++; /* trailing '\0' */
1.103 markus 1326: strlcpy(username, p, sizeof(username));
1.403 djm 1327: if ((r = sshbuf_consume(input, len)) != 0)
1328: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1329: free(c->path);
1330: c->path = NULL;
1.292 djm 1331: if (need == 1) { /* SOCKS4: one string */
1332: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1333: c->path = xstrdup(host);
1.292 djm 1334: } else { /* SOCKS4A: two strings */
1.372 markus 1335: have = sshbuf_len(input);
1336: p = sshbuf_ptr(input);
1.364 djm 1337: if (memchr(p, '\0', have) == NULL) {
1338: error("channel %d: decode socks4a: host not nul "
1339: "terminated", c->self);
1340: return -1;
1341: }
1.292 djm 1342: len = strlen(p);
1343: debug2("channel %d: decode socks4a: host %s/%d",
1344: c->self, p, len);
1345: len++; /* trailing '\0' */
1.293 djm 1346: if (len > NI_MAXHOST) {
1.292 djm 1347: error("channel %d: hostname \"%.100s\" too long",
1348: c->self, p);
1349: return -1;
1350: }
1.293 djm 1351: c->path = xstrdup(p);
1.403 djm 1352: if ((r = sshbuf_consume(input, len)) != 0)
1353: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1354: }
1.103 markus 1355: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1356:
1.194 markus 1357: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1358: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1359:
1.104 markus 1360: if (s4_req.command != 1) {
1.292 djm 1361: debug("channel %d: cannot handle: %s cn %d",
1362: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1363: return -1;
1.103 markus 1364: }
1.104 markus 1365: s4_rsp.version = 0; /* vn: 0 for reply */
1366: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1367: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1368: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1369: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1370: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1371: return 1;
1372: }
1373:
1.193 markus 1374: /* try to decode a socks5 header */
1375: #define SSH_SOCKS5_AUTHDONE 0x1000
1376: #define SSH_SOCKS5_NOAUTH 0x00
1377: #define SSH_SOCKS5_IPV4 0x01
1378: #define SSH_SOCKS5_DOMAIN 0x03
1379: #define SSH_SOCKS5_IPV6 0x04
1380: #define SSH_SOCKS5_CONNECT 0x01
1381: #define SSH_SOCKS5_SUCCESS 0x00
1382:
1383: static int
1.372 markus 1384: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1385: {
1.367 djm 1386: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1387: struct {
1388: u_int8_t version;
1389: u_int8_t command;
1390: u_int8_t reserved;
1391: u_int8_t atyp;
1392: } s5_req, s5_rsp;
1393: u_int16_t dest_port;
1.324 djm 1394: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1395: const u_char *p;
1.252 djm 1396: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1397: int r;
1.193 markus 1398:
1399: debug2("channel %d: decode socks5", c->self);
1.372 markus 1400: p = sshbuf_ptr(input);
1.193 markus 1401: if (p[0] != 0x05)
1402: return -1;
1.372 markus 1403: have = sshbuf_len(input);
1.193 markus 1404: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1405: /* format: ver | nmethods | methods */
1.198 djm 1406: if (have < 2)
1.193 markus 1407: return 0;
1408: nmethods = p[1];
1409: if (have < nmethods + 2)
1410: return 0;
1411: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1412: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1413: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1414: found = 1;
1415: break;
1416: }
1417: }
1418: if (!found) {
1419: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1420: c->self);
1421: return -1;
1422: }
1.403 djm 1423: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1424: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1425: /* version, method */
1.372 markus 1426: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1427: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1428: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1429: c->flags |= SSH_SOCKS5_AUTHDONE;
1430: debug2("channel %d: socks5 auth done", c->self);
1431: return 0; /* need more */
1432: }
1433: debug2("channel %d: socks5 post auth", c->self);
1434: if (have < sizeof(s5_req)+1)
1435: return 0; /* need more */
1.247 deraadt 1436: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1437: if (s5_req.version != 0x05 ||
1438: s5_req.command != SSH_SOCKS5_CONNECT ||
1439: s5_req.reserved != 0x00) {
1.194 markus 1440: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1441: return -1;
1442: }
1.213 deraadt 1443: switch (s5_req.atyp){
1.193 markus 1444: case SSH_SOCKS5_IPV4:
1445: addrlen = 4;
1446: af = AF_INET;
1447: break;
1448: case SSH_SOCKS5_DOMAIN:
1449: addrlen = p[sizeof(s5_req)];
1450: af = -1;
1451: break;
1452: case SSH_SOCKS5_IPV6:
1453: addrlen = 16;
1454: af = AF_INET6;
1455: break;
1456: default:
1.194 markus 1457: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1458: return -1;
1459: }
1.252 djm 1460: need = sizeof(s5_req) + addrlen + 2;
1461: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1462: need++;
1463: if (have < need)
1.193 markus 1464: return 0;
1.403 djm 1465: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1466: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1467: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1468: /* host string length */
1.403 djm 1469: if ((r = sshbuf_consume(input, 1)) != 0)
1470: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1471: }
1.372 markus 1472: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1473: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1474: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1475: return -1;
1476: }
1.193 markus 1477: dest_addr[addrlen] = '\0';
1.321 djm 1478: free(c->path);
1479: c->path = NULL;
1.293 djm 1480: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1481: if (addrlen >= NI_MAXHOST) {
1.293 djm 1482: error("channel %d: dynamic request: socks5 hostname "
1483: "\"%.100s\" too long", c->self, dest_addr);
1484: return -1;
1485: }
1486: c->path = xstrdup(dest_addr);
1487: } else {
1488: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1489: return -1;
1490: c->path = xstrdup(ntop);
1491: }
1.193 markus 1492: c->host_port = ntohs(dest_port);
1.198 djm 1493:
1.194 markus 1494: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1495: c->self, c->path, c->host_port, s5_req.command);
1496:
1497: s5_rsp.version = 0x05;
1498: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1499: s5_rsp.reserved = 0; /* ignored */
1500: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1501: dest_port = 0; /* ignored */
1502:
1.372 markus 1503: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1504: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1505: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1506: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1507: return 1;
1.301 dtucker 1508: }
1509:
1510: Channel *
1.367 djm 1511: channel_connect_stdio_fwd(struct ssh *ssh,
1.407 djm 1512: const char *host_to_connect, u_short port_to_connect,
1513: int in, int out, int nonblock)
1.301 dtucker 1514: {
1515: Channel *c;
1516:
1.403 djm 1517: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1518:
1.367 djm 1519: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1520: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 djm 1521: 0, "stdio-forward", nonblock);
1.301 dtucker 1522:
1523: c->path = xstrdup(host_to_connect);
1524: c->host_port = port_to_connect;
1525: c->listening_port = 0;
1526: c->force_drain = 1;
1527:
1.367 djm 1528: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1529: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1530:
1531: return c;
1.193 markus 1532: }
1533:
1.104 markus 1534: /* dynamic port forwarding */
1.127 itojun 1535: static void
1.367 djm 1536: channel_pre_dynamic(struct ssh *ssh, Channel *c,
1537: fd_set *readset, fd_set *writeset)
1.104 markus 1538: {
1.367 djm 1539: const u_char *p;
1.217 djm 1540: u_int have;
1541: int ret;
1.103 markus 1542:
1.367 djm 1543: have = sshbuf_len(c->input);
1.104 markus 1544: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1545: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1546: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1547: if (have < 3) {
1.104 markus 1548: /* need more */
1549: FD_SET(c->sock, readset);
1550: return;
1551: }
1552: /* try to guess the protocol */
1.367 djm 1553: p = sshbuf_ptr(c->input);
1554: /* XXX sshbuf_peek_u8? */
1.104 markus 1555: switch (p[0]) {
1556: case 0x04:
1.372 markus 1557: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1558: break;
1559: case 0x05:
1.372 markus 1560: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1561: break;
1562: default:
1563: ret = -1;
1564: break;
1565: }
1566: if (ret < 0) {
1.367 djm 1567: chan_mark_dead(ssh, c);
1.104 markus 1568: } else if (ret == 0) {
1569: debug2("channel %d: pre_dynamic: need more", c->self);
1570: /* need more */
1571: FD_SET(c->sock, readset);
1.372 markus 1572: if (sshbuf_len(c->output))
1573: FD_SET(c->sock, writeset);
1.104 markus 1574: } else {
1575: /* switch to the next state */
1576: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1577: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1578: }
1.103 markus 1579: }
1580:
1.372 markus 1581: /* simulate read-error */
1582: static void
1583: rdynamic_close(struct ssh *ssh, Channel *c)
1584: {
1585: c->type = SSH_CHANNEL_OPEN;
1586: chan_read_failed(ssh, c);
1587: sshbuf_reset(c->input);
1588: chan_ibuf_empty(ssh, c);
1589: sshbuf_reset(c->output);
1590: chan_write_failed(ssh, c);
1591: }
1592:
1593: /* reverse dynamic port forwarding */
1594: static void
1595: channel_before_prepare_select_rdynamic(struct ssh *ssh, Channel *c)
1596: {
1597: const u_char *p;
1598: u_int have, len;
1599: int r, ret;
1600:
1601: have = sshbuf_len(c->output);
1602: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1603: /* sshbuf_dump(c->output, stderr); */
1604: /* EOF received */
1605: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1606: if ((r = sshbuf_consume(c->output, have)) != 0)
1607: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1608: rdynamic_close(ssh, c);
1609: return;
1610: }
1611: /* check if the fixed size part of the packet is in buffer. */
1612: if (have < 3)
1613: return;
1614: /* try to guess the protocol */
1615: p = sshbuf_ptr(c->output);
1616: switch (p[0]) {
1617: case 0x04:
1618: /* switch input/output for reverse forwarding */
1619: ret = channel_decode_socks4(c, c->output, c->input);
1620: break;
1621: case 0x05:
1622: ret = channel_decode_socks5(c, c->output, c->input);
1623: break;
1624: default:
1625: ret = -1;
1626: break;
1627: }
1628: if (ret < 0) {
1629: rdynamic_close(ssh, c);
1630: } else if (ret == 0) {
1631: debug2("channel %d: pre_rdynamic: need more", c->self);
1632: /* send socks request to peer */
1633: len = sshbuf_len(c->input);
1634: if (len > 0 && len < c->remote_window) {
1635: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1636: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1637: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1638: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1639: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1640: }
1.403 djm 1641: if ((r = sshbuf_consume(c->input, len)) != 0)
1642: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1643: c->remote_window -= len;
1644: }
1645: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1646: /* the connect failed */
1647: rdynamic_close(ssh, c);
1648: }
1649: }
1650:
1.41 markus 1651: /* This is our fake X11 server socket. */
1.127 itojun 1652: static void
1.367 djm 1653: channel_post_x11_listener(struct ssh *ssh, Channel *c,
1654: fd_set *readset, fd_set *writeset)
1.41 markus 1655: {
1.113 markus 1656: Channel *nc;
1.285 djm 1657: struct sockaddr_storage addr;
1.367 djm 1658: int r, newsock, oerrno, remote_port;
1.41 markus 1659: socklen_t addrlen;
1.85 markus 1660: char buf[16384], *remote_ipaddr;
1.25 markus 1661:
1.367 djm 1662: if (!FD_ISSET(c->sock, readset))
1663: return;
1664:
1665: debug("X11 connection requested.");
1666: addrlen = sizeof(addr);
1667: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1668: if (c->single_connection) {
1669: oerrno = errno;
1670: debug2("single_connection: closing X11 listener.");
1.407 djm 1671: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1672: chan_mark_dead(ssh, c);
1673: errno = oerrno;
1674: }
1.393 deraadt 1675: if (newsock == -1) {
1.367 djm 1676: if (errno != EINTR && errno != EWOULDBLOCK &&
1677: errno != ECONNABORTED)
1678: error("accept: %.100s", strerror(errno));
1679: if (errno == EMFILE || errno == ENFILE)
1680: c->notbefore = monotime() + 1;
1681: return;
1682: }
1683: set_nodelay(newsock);
1684: remote_ipaddr = get_peer_ipaddr(newsock);
1685: remote_port = get_peer_port(newsock);
1686: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1687: remote_ipaddr, remote_port);
1688:
1689: nc = channel_new(ssh, "accepted x11 socket",
1690: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1691: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1692: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1693: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1694: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1695: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1696: }
1.367 djm 1697: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1698: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1699: free(remote_ipaddr);
1.41 markus 1700: }
1.25 markus 1701:
1.127 itojun 1702: static void
1.367 djm 1703: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1704: {
1.328 djm 1705: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1706: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1707: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1708: int remote_port = get_peer_port(c->sock);
1.367 djm 1709: int r;
1.303 djm 1710:
1711: if (remote_port == -1) {
1712: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1713: free(remote_ipaddr);
1.303 djm 1714: remote_ipaddr = xstrdup("127.0.0.1");
1715: remote_port = 65535;
1716: }
1.103 markus 1717:
1.367 djm 1718: free(c->remote_name);
1719: xasprintf(&c->remote_name,
1.103 markus 1720: "%s: listening port %d for %.100s port %d, "
1.328 djm 1721: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1722: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1723: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1724:
1.367 djm 1725: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1726: if (strcmp(rtype, "direct-tcpip") == 0) {
1727: /* target host, port */
1.367 djm 1728: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1729: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1730: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1731: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1732: /* target path */
1.403 djm 1733: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1734: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1735: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1736: /* listen path */
1.403 djm 1737: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1738: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1739: } else {
1.358 djm 1740: /* listen address, port */
1.367 djm 1741: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1742: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1743: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1744: }
1745: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1746: /* reserved for future owner/mode info */
1.403 djm 1747: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1748: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1749: } else {
1750: /* originator host and port */
1.367 djm 1751: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1752: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1753: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1754: }
1.367 djm 1755: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1756: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1757: free(remote_ipaddr);
1.328 djm 1758: free(local_ipaddr);
1.103 markus 1759: }
1760:
1.347 djm 1761: void
1.367 djm 1762: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1763: {
1.367 djm 1764: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1765: }
1766:
1.41 markus 1767: /*
1768: * This socket is listening for connections to a forwarded TCP/IP port.
1769: */
1.127 itojun 1770: static void
1.367 djm 1771: channel_post_port_listener(struct ssh *ssh, Channel *c,
1772: fd_set *readset, fd_set *writeset)
1.41 markus 1773: {
1.103 markus 1774: Channel *nc;
1.285 djm 1775: struct sockaddr_storage addr;
1.113 markus 1776: int newsock, nextstate;
1.41 markus 1777: socklen_t addrlen;
1.103 markus 1778: char *rtype;
1.73 markus 1779:
1.367 djm 1780: if (!FD_ISSET(c->sock, readset))
1781: return;
1782:
1783: debug("Connection to port %d forwarding to %.100s port %d requested.",
1784: c->listening_port, c->path, c->host_port);
1.103 markus 1785:
1.367 djm 1786: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1787: nextstate = SSH_CHANNEL_OPENING;
1788: rtype = "forwarded-tcpip";
1789: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1790: nextstate = SSH_CHANNEL_OPENING;
1791: rtype = "forwarded-streamlocal@openssh.com";
1792: } else if (c->host_port == PORT_STREAMLOCAL) {
1793: nextstate = SSH_CHANNEL_OPENING;
1794: rtype = "direct-streamlocal@openssh.com";
1795: } else if (c->host_port == 0) {
1796: nextstate = SSH_CHANNEL_DYNAMIC;
1797: rtype = "dynamic-tcpip";
1798: } else {
1799: nextstate = SSH_CHANNEL_OPENING;
1800: rtype = "direct-tcpip";
1801: }
1.103 markus 1802:
1.367 djm 1803: addrlen = sizeof(addr);
1804: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1805: if (newsock == -1) {
1.367 djm 1806: if (errno != EINTR && errno != EWOULDBLOCK &&
1807: errno != ECONNABORTED)
1808: error("accept: %.100s", strerror(errno));
1809: if (errno == EMFILE || errno == ENFILE)
1810: c->notbefore = monotime() + 1;
1811: return;
1.41 markus 1812: }
1.367 djm 1813: if (c->host_port != PORT_STREAMLOCAL)
1814: set_nodelay(newsock);
1815: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1816: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1817: nc->listening_port = c->listening_port;
1818: nc->host_port = c->host_port;
1819: if (c->path != NULL)
1820: nc->path = xstrdup(c->path);
1821:
1822: if (nextstate != SSH_CHANNEL_DYNAMIC)
1823: port_open_helper(ssh, nc, rtype);
1.41 markus 1824: }
1.25 markus 1825:
1.41 markus 1826: /*
1827: * This is the authentication agent socket listening for connections from
1828: * clients.
1829: */
1.127 itojun 1830: static void
1.367 djm 1831: channel_post_auth_listener(struct ssh *ssh, Channel *c,
1832: fd_set *readset, fd_set *writeset)
1.41 markus 1833: {
1.113 markus 1834: Channel *nc;
1.367 djm 1835: int r, newsock;
1.285 djm 1836: struct sockaddr_storage addr;
1.41 markus 1837: socklen_t addrlen;
1.25 markus 1838:
1.367 djm 1839: if (!FD_ISSET(c->sock, readset))
1840: return;
1841:
1842: addrlen = sizeof(addr);
1843: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1844: if (newsock == -1) {
1.367 djm 1845: error("accept from auth socket: %.100s", strerror(errno));
1846: if (errno == EMFILE || errno == ENFILE)
1847: c->notbefore = monotime() + 1;
1848: return;
1.41 markus 1849: }
1.367 djm 1850: nc = channel_new(ssh, "accepted auth socket",
1851: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1852: c->local_window_max, c->local_maxpacket,
1853: 0, "accepted auth socket", 1);
1854: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1855: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1856: fatal_fr(r, "channel %i", c->self);
1.41 markus 1857: }
1.25 markus 1858:
1.127 itojun 1859: static void
1.367 djm 1860: channel_post_connecting(struct ssh *ssh, Channel *c,
1861: fd_set *readset, fd_set *writeset)
1.75 markus 1862: {
1.372 markus 1863: int err = 0, sock, isopen, r;
1.129 stevesk 1864: socklen_t sz = sizeof(err);
1.114 markus 1865:
1.367 djm 1866: if (!FD_ISSET(c->sock, writeset))
1867: return;
1.368 djm 1868: if (!c->have_remote_id)
1.403 djm 1869: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1870: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1871: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 deraadt 1872: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1873: err = errno;
1874: error("getsockopt SO_ERROR failed");
1875: }
1876: if (err == 0) {
1877: debug("channel %d: connected to %s port %d",
1878: c->self, c->connect_ctx.host, c->connect_ctx.port);
1879: channel_connect_ctx_free(&c->connect_ctx);
1880: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1881: if (isopen) {
1882: /* no message necessary */
1883: } else {
1884: if ((r = sshpkt_start(ssh,
1885: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1886: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1887: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1888: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 1889: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1890: (r = sshpkt_send(ssh)) != 0)
1891: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 1892: }
1893: } else {
1894: debug("channel %d: connection failed: %s",
1895: c->self, strerror(err));
1896: /* Try next address, if any */
1897: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1898: close(c->sock);
1899: c->sock = c->rfd = c->wfd = sock;
1900: channel_find_maxfd(ssh->chanctxt);
1901: return;
1902: }
1903: /* Exhausted all addresses */
1904: error("connect_to %.100s port %d: failed.",
1905: c->connect_ctx.host, c->connect_ctx.port);
1906: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1907: if (isopen) {
1908: rdynamic_close(ssh, c);
1909: } else {
1910: if ((r = sshpkt_start(ssh,
1911: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1912: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1913: (r = sshpkt_put_u32(ssh,
1914: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1915: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 1916: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1917: (r = sshpkt_send(ssh)) != 0)
1918: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 1919: chan_mark_dead(ssh, c);
1.75 markus 1920: }
1921: }
1922: }
1923:
1.127 itojun 1924: static int
1.367 djm 1925: channel_handle_rfd(struct ssh *ssh, Channel *c,
1926: fd_set *readset, fd_set *writeset)
1.41 markus 1927: {
1.214 markus 1928: char buf[CHAN_RBUF];
1.367 djm 1929: ssize_t len;
1930: int r;
1.25 markus 1931:
1.367 djm 1932: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
1933: return 1;
1934:
1935: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 1936: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1937: return 1;
1938: if (len <= 0) {
1939: debug2("channel %d: read<=0 rfd %d len %zd",
1940: c->self, c->rfd, len);
1941: if (c->type != SSH_CHANNEL_OPEN) {
1942: debug2("channel %d: not open", c->self);
1943: chan_mark_dead(ssh, c);
1.41 markus 1944: return -1;
1.65 markus 1945: } else {
1.367 djm 1946: chan_read_failed(ssh, c);
1.65 markus 1947: }
1.367 djm 1948: return -1;
1949: }
1950: if (c->input_filter != NULL) {
1951: if (c->input_filter(ssh, c, buf, len) == -1) {
1952: debug2("channel %d: filter stops", c->self);
1953: chan_read_failed(ssh, c);
1954: }
1955: } else if (c->datagram) {
1956: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 1957: fatal_fr(r, "channel %i: put datagram", c->self);
1958: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
1959: fatal_fr(r, "channel %i: put data", c->self);
1.41 markus 1960: return 1;
1961: }
1.241 deraadt 1962:
1.127 itojun 1963: static int
1.367 djm 1964: channel_handle_wfd(struct ssh *ssh, Channel *c,
1965: fd_set *readset, fd_set *writeset)
1.41 markus 1966: {
1.95 markus 1967: struct termios tio;
1.367 djm 1968: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1969: size_t dlen, olen = 0;
1970: int r, len;
1971:
1972: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
1973: sshbuf_len(c->output) == 0)
1974: return 1;
1.25 markus 1975:
1.41 markus 1976: /* Send buffered output data to the socket. */
1.367 djm 1977: olen = sshbuf_len(c->output);
1978: if (c->output_filter != NULL) {
1979: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1980: debug2("channel %d: filter stops", c->self);
1981: if (c->type != SSH_CHANNEL_OPEN)
1982: chan_mark_dead(ssh, c);
1983: else
1984: chan_write_failed(ssh, c);
1985: return -1;
1.231 reyk 1986: }
1.367 djm 1987: } else if (c->datagram) {
1988: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 1989: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 1990: buf = data;
1.367 djm 1991: } else {
1992: buf = data = sshbuf_mutable_ptr(c->output);
1993: dlen = sshbuf_len(c->output);
1994: }
1.231 reyk 1995:
1.367 djm 1996: if (c->datagram) {
1997: /* ignore truncated writes, datagrams might get lost */
1.374 djm 1998: len = write(c->wfd, buf, dlen);
1.367 djm 1999: free(data);
1.393 deraadt 2000: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 2001: return 1;
1.367 djm 2002: if (len <= 0)
2003: goto write_fail;
2004: goto out;
2005: }
2006:
2007: len = write(c->wfd, buf, dlen);
1.393 deraadt 2008: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2009: return 1;
2010: if (len <= 0) {
2011: write_fail:
2012: if (c->type != SSH_CHANNEL_OPEN) {
2013: debug2("channel %d: not open", c->self);
2014: chan_mark_dead(ssh, c);
1.41 markus 2015: return -1;
1.367 djm 2016: } else {
2017: chan_write_failed(ssh, c);
1.91 markus 2018: }
1.367 djm 2019: return -1;
2020: }
2021: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2022: if (tcgetattr(c->wfd, &tio) == 0 &&
2023: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2024: /*
2025: * Simulate echo to reduce the impact of
2026: * traffic analysis. We need to match the
2027: * size of a SSH2_MSG_CHANNEL_DATA message
2028: * (4 byte channel id + buf)
2029: */
2030: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2031: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2032: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2033: }
1.367 djm 2034: }
1.403 djm 2035: if ((r = sshbuf_consume(c->output, len)) != 0)
2036: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2037: out:
1.367 djm 2038: c->local_consumed += olen - sshbuf_len(c->output);
2039:
2040: return 1;
2041: }
2042:
2043: static int
2044: channel_handle_efd_write(struct ssh *ssh, Channel *c,
2045: fd_set *readset, fd_set *writeset)
2046: {
2047: int r;
2048: ssize_t len;
2049:
2050: if (!FD_ISSET(c->efd, writeset) || sshbuf_len(c->extended) == 0)
2051: return 1;
2052:
2053: len = write(c->efd, sshbuf_ptr(c->extended),
2054: sshbuf_len(c->extended));
2055: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2056: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2057: return 1;
2058: if (len <= 0) {
2059: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2060: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2061: } else {
1.403 djm 2062: if ((r = sshbuf_consume(c->extended, len)) != 0)
2063: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2064: c->local_consumed += len;
2065: }
1.44 markus 2066: return 1;
2067: }
1.241 deraadt 2068:
1.127 itojun 2069: static int
1.367 djm 2070: channel_handle_efd_read(struct ssh *ssh, Channel *c,
2071: fd_set *readset, fd_set *writeset)
1.44 markus 2072: {
1.214 markus 2073: char buf[CHAN_RBUF];
1.367 djm 2074: int r;
2075: ssize_t len;
2076:
2077: if (!FD_ISSET(c->efd, readset))
2078: return 1;
1.44 markus 2079:
1.367 djm 2080: len = read(c->efd, buf, sizeof(buf));
2081: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2082: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2083: return 1;
2084: if (len <= 0) {
1.403 djm 2085: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2086: channel_close_fd(ssh, c, &c->efd);
1.403 djm 2087: } else if (c->extended_usage == CHAN_EXTENDED_IGNORE)
2088: debug3("channel %d: discard efd", c->self);
2089: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2090: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2091: return 1;
2092: }
1.241 deraadt 2093:
1.127 itojun 2094: static int
1.367 djm 2095: channel_handle_efd(struct ssh *ssh, Channel *c,
2096: fd_set *readset, fd_set *writeset)
1.44 markus 2097: {
1.367 djm 2098: if (c->efd == -1)
2099: return 1;
2100:
2101: /** XXX handle drain efd, too */
2102:
2103: if (c->extended_usage == CHAN_EXTENDED_WRITE)
2104: return channel_handle_efd_write(ssh, c, readset, writeset);
2105: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2106: c->extended_usage == CHAN_EXTENDED_IGNORE)
2107: return channel_handle_efd_read(ssh, c, readset, writeset);
2108:
2109: return 1;
2110: }
2111:
2112: static int
2113: channel_check_window(struct ssh *ssh, Channel *c)
2114: {
2115: int r;
2116:
1.104 markus 2117: if (c->type == SSH_CHANNEL_OPEN &&
2118: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2119: ((c->local_window_max - c->local_window >
1.269 markus 2120: c->local_maxpacket*3) ||
2121: c->local_window < c->local_window_max/2) &&
1.44 markus 2122: c->local_consumed > 0) {
1.368 djm 2123: if (!c->have_remote_id)
1.403 djm 2124: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2125: if ((r = sshpkt_start(ssh,
2126: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2127: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2128: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2129: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2130: fatal_fr(r, "channel %i", c->self);
1.367 djm 2131: }
1.403 djm 2132: debug2("channel %d: window %d sent adjust %d", c->self,
2133: c->local_window, c->local_consumed);
1.44 markus 2134: c->local_window += c->local_consumed;
2135: c->local_consumed = 0;
1.1 deraadt 2136: }
1.41 markus 2137: return 1;
1.1 deraadt 2138: }
2139:
1.127 itojun 2140: static void
1.367 djm 2141: channel_post_open(struct ssh *ssh, Channel *c,
2142: fd_set *readset, fd_set *writeset)
1.41 markus 2143: {
1.367 djm 2144: channel_handle_rfd(ssh, c, readset, writeset);
2145: channel_handle_wfd(ssh, c, readset, writeset);
2146: channel_handle_efd(ssh, c, readset, writeset);
2147: channel_check_window(ssh, c);
1.44 markus 2148: }
2149:
1.302 djm 2150: static u_int
1.367 djm 2151: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2152: {
2153: char buf[CHAN_RBUF];
1.367 djm 2154: ssize_t len;
1.302 djm 2155: u_int rlen;
1.367 djm 2156: int r;
1.302 djm 2157:
1.367 djm 2158: if (sshbuf_len(c->input) < need) {
2159: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2160: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2161: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2162: return sshbuf_len(c->input);
1.302 djm 2163: if (len <= 0) {
1.367 djm 2164: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2165: c->self, c->rfd, len);
1.367 djm 2166: chan_read_failed(ssh, c);
1.349 naddy 2167: return 0;
1.403 djm 2168: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2169: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2170: }
1.367 djm 2171: return sshbuf_len(c->input);
1.302 djm 2172: }
2173:
2174: static void
1.367 djm 2175: channel_post_mux_client_read(struct ssh *ssh, Channel *c,
2176: fd_set *readset, fd_set *writeset)
1.302 djm 2177: {
2178: u_int need;
2179:
1.367 djm 2180: if (c->rfd == -1 || !FD_ISSET(c->rfd, readset))
2181: return;
2182: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2183: return;
2184: if (c->mux_pause)
2185: return;
2186:
2187: /*
2188: * Don't not read past the precise end of packets to
2189: * avoid disrupting fd passing.
2190: */
2191: if (read_mux(ssh, c, 4) < 4) /* read header */
2192: return;
2193: /* XXX sshbuf_peek_u32 */
2194: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2195: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2196: if (need > CHANNEL_MUX_MAX_PACKET) {
2197: debug2("channel %d: packet too big %u > %u",
2198: c->self, CHANNEL_MUX_MAX_PACKET, need);
2199: chan_rcvd_oclose(ssh, c);
2200: return;
2201: }
2202: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2203: return;
2204: if (c->mux_rcb(ssh, c) != 0) {
2205: debug("channel %d: mux_rcb failed", c->self);
2206: chan_mark_dead(ssh, c);
2207: return;
1.302 djm 2208: }
1.367 djm 2209: }
2210:
2211: static void
2212: channel_post_mux_client_write(struct ssh *ssh, Channel *c,
2213: fd_set *readset, fd_set *writeset)
2214: {
2215: ssize_t len;
2216: int r;
1.302 djm 2217:
1.367 djm 2218: if (c->wfd == -1 || !FD_ISSET(c->wfd, writeset) ||
2219: sshbuf_len(c->output) == 0)
2220: return;
2221:
2222: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2223: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2224: return;
2225: if (len <= 0) {
2226: chan_mark_dead(ssh, c);
2227: return;
1.302 djm 2228: }
1.367 djm 2229: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2230: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2231: }
2232:
2233: static void
2234: channel_post_mux_client(struct ssh *ssh, Channel *c,
2235: fd_set *readset, fd_set *writeset)
2236: {
2237: channel_post_mux_client_read(ssh, c, readset, writeset);
2238: channel_post_mux_client_write(ssh, c, readset, writeset);
1.302 djm 2239: }
2240:
2241: static void
1.367 djm 2242: channel_post_mux_listener(struct ssh *ssh, Channel *c,
2243: fd_set *readset, fd_set *writeset)
1.302 djm 2244: {
2245: Channel *nc;
2246: struct sockaddr_storage addr;
2247: socklen_t addrlen;
2248: int newsock;
2249: uid_t euid;
2250: gid_t egid;
2251:
2252: if (!FD_ISSET(c->sock, readset))
2253: return;
2254:
2255: debug("multiplexing control connection");
2256:
2257: /*
2258: * Accept connection on control socket
2259: */
2260: memset(&addr, 0, sizeof(addr));
2261: addrlen = sizeof(addr);
2262: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2263: &addrlen)) == -1) {
1.403 djm 2264: error_f("accept: %s", strerror(errno));
1.317 djm 2265: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2266: c->notbefore = monotime() + 1;
1.302 djm 2267: return;
2268: }
2269:
1.393 deraadt 2270: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2271: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2272: close(newsock);
2273: return;
2274: }
2275: if ((euid != 0) && (getuid() != euid)) {
2276: error("multiplex uid mismatch: peer euid %u != uid %u",
2277: (u_int)euid, (u_int)getuid());
2278: close(newsock);
2279: return;
2280: }
1.367 djm 2281: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2282: newsock, newsock, -1, c->local_window_max,
2283: c->local_maxpacket, 0, "mux-control", 1);
2284: nc->mux_rcb = c->mux_rcb;
1.403 djm 2285: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2286: /* establish state */
1.367 djm 2287: nc->mux_rcb(ssh, nc);
1.302 djm 2288: /* mux state transitions must not elicit protocol messages */
2289: nc->flags |= CHAN_LOCAL;
2290: }
2291:
1.127 itojun 2292: static void
1.367 djm 2293: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2294: {
1.367 djm 2295: chan_fn **pre, **post;
2296:
2297: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2298: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2299: fatal_f("allocation failed");
1.367 djm 2300:
2301: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2302: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2303: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2304: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2305: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2306: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2307: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2308: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2309: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2310: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2311: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2312: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2313: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2314:
2315: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2316: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2317: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2318: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2319: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2320: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2321: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2322: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2323: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2324: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2325: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2326: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2327:
1.367 djm 2328: sc->channel_pre = pre;
2329: sc->channel_post = post;
1.44 markus 2330: }
2331:
1.140 markus 2332: /* gc dead channels */
2333: static void
1.367 djm 2334: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2335: {
2336: if (c == NULL)
2337: return;
2338: if (c->detach_user != NULL) {
1.367 djm 2339: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2340: return;
1.385 djm 2341:
1.194 markus 2342: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2343: c->detach_user(ssh, c->self, NULL);
1.140 markus 2344: /* if we still have a callback */
2345: if (c->detach_user != NULL)
2346: return;
1.194 markus 2347: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2348: }
1.367 djm 2349: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2350: return;
1.194 markus 2351: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2352: channel_free(ssh, c);
1.140 markus 2353: }
2354:
1.367 djm 2355: enum channel_table { CHAN_PRE, CHAN_POST };
2356:
1.127 itojun 2357: static void
1.367 djm 2358: channel_handler(struct ssh *ssh, int table,
1.366 djm 2359: fd_set *readset, fd_set *writeset, time_t *unpause_secs)
1.41 markus 2360: {
1.367 djm 2361: struct ssh_channels *sc = ssh->chanctxt;
2362: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2363: u_int i, oalloc;
1.41 markus 2364: Channel *c;
1.317 djm 2365: time_t now;
1.25 markus 2366:
1.322 dtucker 2367: now = monotime();
1.317 djm 2368: if (unpause_secs != NULL)
2369: *unpause_secs = 0;
1.367 djm 2370: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2371: c = sc->channels[i];
1.113 markus 2372: if (c == NULL)
1.41 markus 2373: continue;
1.299 markus 2374: if (c->delayed) {
1.367 djm 2375: if (table == CHAN_PRE)
1.299 markus 2376: c->delayed = 0;
2377: else
2378: continue;
2379: }
1.317 djm 2380: if (ftab[c->type] != NULL) {
2381: /*
2382: * Run handlers that are not paused.
2383: */
2384: if (c->notbefore <= now)
1.367 djm 2385: (*ftab[c->type])(ssh, c, readset, writeset);
1.317 djm 2386: else if (unpause_secs != NULL) {
2387: /*
2388: * Collect the time that the earliest
2389: * channel comes off pause.
2390: */
1.403 djm 2391: debug3_f("chan %d: skip for %d more "
2392: "seconds", c->self,
1.317 djm 2393: (int)(c->notbefore - now));
2394: if (*unpause_secs == 0 ||
2395: (c->notbefore - now) < *unpause_secs)
2396: *unpause_secs = c->notbefore - now;
2397: }
2398: }
1.367 djm 2399: channel_garbage_collect(ssh, c);
1.1 deraadt 2400: }
1.317 djm 2401: if (unpause_secs != NULL && *unpause_secs != 0)
1.403 djm 2402: debug3_f("first channel unpauses in %d seconds",
2403: (int)*unpause_secs);
1.1 deraadt 2404: }
2405:
1.121 markus 2406: /*
1.372 markus 2407: * Create sockets before allocating the select bitmasks.
2408: * This is necessary for things that need to happen after reading
2409: * the network-input but before channel_prepare_select().
2410: */
2411: static void
2412: channel_before_prepare_select(struct ssh *ssh)
2413: {
2414: struct ssh_channels *sc = ssh->chanctxt;
2415: Channel *c;
2416: u_int i, oalloc;
2417:
2418: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2419: c = sc->channels[i];
2420: if (c == NULL)
2421: continue;
2422: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
2423: channel_before_prepare_select_rdynamic(ssh, c);
2424: }
2425: }
2426:
2427: /*
1.121 markus 2428: * Allocate/update select bitmasks and add any bits relevant to channels in
2429: * select bitmasks.
2430: */
1.49 markus 2431: void
1.366 djm 2432: channel_prepare_select(struct ssh *ssh, fd_set **readsetp, fd_set **writesetp,
2433: int *maxfdp, u_int *nallocp, time_t *minwait_secs)
1.41 markus 2434: {
1.243 djm 2435: u_int n, sz, nfdset;
1.84 markus 2436:
1.372 markus 2437: channel_before_prepare_select(ssh); /* might update channel_max_fd */
2438:
1.367 djm 2439: n = MAXIMUM(*maxfdp, ssh->chanctxt->channel_max_fd);
1.84 markus 2440:
1.243 djm 2441: nfdset = howmany(n+1, NFDBITS);
2442: /* Explicitly test here, because xrealloc isn't always called */
1.341 millert 2443: if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask))
1.243 djm 2444: fatal("channel_prepare_select: max_fd (%d) is too large", n);
2445: sz = nfdset * sizeof(fd_mask);
2446:
1.132 markus 2447: /* perhaps check sz < nalloc/2 and shrink? */
2448: if (*readsetp == NULL || sz > *nallocp) {
1.342 deraadt 2449: *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask));
2450: *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask));
1.132 markus 2451: *nallocp = sz;
1.84 markus 2452: }
1.132 markus 2453: *maxfdp = n;
1.84 markus 2454: memset(*readsetp, 0, sz);
2455: memset(*writesetp, 0, sz);
2456:
1.366 djm 2457: if (!ssh_packet_is_rekeying(ssh))
1.367 djm 2458: channel_handler(ssh, CHAN_PRE, *readsetp, *writesetp,
1.317 djm 2459: minwait_secs);
1.41 markus 2460: }
2461:
1.121 markus 2462: /*
2463: * After select, perform any appropriate operations for channels which have
2464: * events pending.
2465: */
1.49 markus 2466: void
1.366 djm 2467: channel_after_select(struct ssh *ssh, fd_set *readset, fd_set *writeset)
1.41 markus 2468: {
1.367 djm 2469: channel_handler(ssh, CHAN_POST, readset, writeset, NULL);
2470: }
2471:
2472: /*
2473: * Enqueue data for channels with open or draining c->input.
2474: */
2475: static void
2476: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2477: {
1.373 djm 2478: size_t len, plen;
2479: const u_char *pkt;
1.367 djm 2480: int r;
2481:
2482: if ((len = sshbuf_len(c->input)) == 0) {
2483: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2484: /*
2485: * input-buffer is empty and read-socket shutdown:
2486: * tell peer, that we will not send more data:
2487: * send IEOF.
2488: * hack for extended data: delay EOF if EFD still
2489: * in use.
2490: */
2491: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2492: debug2("channel %d: "
2493: "ibuf_empty delayed efd %d/(%zu)",
2494: c->self, c->efd, sshbuf_len(c->extended));
2495: else
2496: chan_ibuf_empty(ssh, c);
2497: }
2498: return;
2499: }
2500:
1.368 djm 2501: if (!c->have_remote_id)
1.403 djm 2502: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2503:
1.367 djm 2504: if (c->datagram) {
2505: /* Check datagram will fit; drop if not */
1.373 djm 2506: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2507: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2508: /*
2509: * XXX this does tail-drop on the datagram queue which is
2510: * usually suboptimal compared to head-drop. Better to have
2511: * backpressure at read time? (i.e. read + discard)
2512: */
1.373 djm 2513: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2514: debug("channel %d: datagram too big", c->self);
2515: return;
2516: }
2517: /* Enqueue it */
2518: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2519: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2520: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2521: (r = sshpkt_send(ssh)) != 0)
2522: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2523: c->remote_window -= plen;
1.367 djm 2524: return;
2525: }
2526:
2527: /* Enqueue packet for buffered data. */
2528: if (len > c->remote_window)
2529: len = c->remote_window;
2530: if (len > c->remote_maxpacket)
2531: len = c->remote_maxpacket;
2532: if (len == 0)
2533: return;
2534: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2535: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2536: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2537: (r = sshpkt_send(ssh)) != 0)
2538: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2539: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2540: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2541: c->remote_window -= len;
1.41 markus 2542: }
2543:
1.367 djm 2544: /*
2545: * Enqueue data for channels with open c->extended in read mode.
2546: */
2547: static void
2548: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2549: {
2550: size_t len;
2551: int r;
2552:
2553: if ((len = sshbuf_len(c->extended)) == 0)
2554: return;
2555:
2556: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2557: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2558: if (len > c->remote_window)
2559: len = c->remote_window;
2560: if (len > c->remote_maxpacket)
2561: len = c->remote_maxpacket;
2562: if (len == 0)
2563: return;
1.368 djm 2564: if (!c->have_remote_id)
1.403 djm 2565: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2566: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2567: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2568: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2569: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2570: (r = sshpkt_send(ssh)) != 0)
2571: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2572: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2573: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2574: c->remote_window -= len;
2575: debug2("channel %d: sent ext data %zu", c->self, len);
2576: }
1.121 markus 2577:
1.84 markus 2578: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2579: void
1.367 djm 2580: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2581: {
1.367 djm 2582: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2583: Channel *c;
1.367 djm 2584: u_int i;
1.1 deraadt 2585:
1.367 djm 2586: for (i = 0; i < sc->channels_alloc; i++) {
2587: c = sc->channels[i];
1.113 markus 2588: if (c == NULL)
2589: continue;
1.37 markus 2590:
1.121 markus 2591: /*
2592: * We are only interested in channels that can have buffered
2593: * incoming data.
2594: */
1.358 djm 2595: if (c->type != SSH_CHANNEL_OPEN)
2596: continue;
2597: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2598: /* XXX is this true? */
1.367 djm 2599: debug3("channel %d: will not send data after close",
2600: c->self);
1.44 markus 2601: continue;
2602: }
1.25 markus 2603:
2604: /* Get the amount of buffered data for this channel. */
1.367 djm 2605: if (c->istate == CHAN_INPUT_OPEN ||
2606: c->istate == CHAN_INPUT_WAIT_DRAIN)
2607: channel_output_poll_input_open(ssh, c);
1.44 markus 2608: /* Send extended data, i.e. stderr */
1.358 djm 2609: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2610: c->extended_usage == CHAN_EXTENDED_READ)
2611: channel_output_poll_extended_read(ssh, c);
1.25 markus 2612: }
1.1 deraadt 2613: }
2614:
1.354 markus 2615: /* -- mux proxy support */
2616:
2617: /*
2618: * When multiplexing channel messages for mux clients we have to deal
2619: * with downstream messages from the mux client and upstream messages
2620: * from the ssh server:
2621: * 1) Handling downstream messages is straightforward and happens
2622: * in channel_proxy_downstream():
2623: * - We forward all messages (mostly) unmodified to the server.
2624: * - However, in order to route messages from upstream to the correct
2625: * downstream client, we have to replace the channel IDs used by the
2626: * mux clients with a unique channel ID because the mux clients might
2627: * use conflicting channel IDs.
2628: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2629: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2630: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2631: * with the newly allocated channel ID.
2632: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2633: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2634: * is then translated back to the original mux client ID.
2635: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2636: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2637: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2638: * downstream mux client are removed.
2639: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2640: * requires more work, because they are not addressed to a specific
2641: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2642: * out whether the request is addressed to the local client or a
2643: * specific downstream client based on the listen-address/port.
1.380 djm 2644: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2645: * not supported as the matching session/channel cannot be identified
2646: * easily.
2647: */
2648:
2649: /*
2650: * receive packets from downstream mux clients:
2651: * channel callback fired on read from mux client, creates
2652: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2653: * on channel creation.
2654: */
2655: int
1.367 djm 2656: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2657: {
2658: Channel *c = NULL;
2659: struct sshbuf *original = NULL, *modified = NULL;
2660: const u_char *cp;
2661: char *ctype = NULL, *listen_host = NULL;
2662: u_char type;
2663: size_t have;
1.370 djm 2664: int ret = -1, r;
1.355 djm 2665: u_int id, remote_id, listen_port;
1.354 markus 2666:
1.367 djm 2667: /* sshbuf_dump(downstream->input, stderr); */
2668: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2669: != 0) {
1.403 djm 2670: error_fr(r, "parse");
1.354 markus 2671: return -1;
2672: }
2673: if (have < 2) {
1.403 djm 2674: error_f("short message");
1.354 markus 2675: return -1;
2676: }
2677: type = cp[1];
2678: /* skip padlen + type */
2679: cp += 2;
2680: have -= 2;
2681: if (ssh_packet_log_type(type))
1.403 djm 2682: debug3_f("channel %u: down->up: type %u",
1.354 markus 2683: downstream->self, type);
2684:
2685: switch (type) {
2686: case SSH2_MSG_CHANNEL_OPEN:
2687: if ((original = sshbuf_from(cp, have)) == NULL ||
2688: (modified = sshbuf_new()) == NULL) {
1.403 djm 2689: error_f("alloc");
1.354 markus 2690: goto out;
2691: }
2692: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2693: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2694: error_fr(r, "parse");
1.354 markus 2695: goto out;
2696: }
1.367 djm 2697: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2698: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 2699: c->mux_ctx = downstream; /* point to mux client */
2700: c->mux_downstream_id = id; /* original downstream id */
2701: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2702: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2703: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2704: error_fr(r, "compose");
1.367 djm 2705: channel_free(ssh, c);
1.354 markus 2706: goto out;
2707: }
2708: break;
2709: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2710: /*
2711: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2712: * need to parse 'remote_id' instead of 'ctype'.
2713: */
2714: if ((original = sshbuf_from(cp, have)) == NULL ||
2715: (modified = sshbuf_new()) == NULL) {
1.403 djm 2716: error_f("alloc");
1.354 markus 2717: goto out;
2718: }
2719: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2720: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2721: error_fr(r, "parse");
1.354 markus 2722: goto out;
2723: }
1.367 djm 2724: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2725: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 2726: c->mux_ctx = downstream; /* point to mux client */
2727: c->mux_downstream_id = id;
2728: c->remote_id = remote_id;
1.368 djm 2729: c->have_remote_id = 1;
1.354 markus 2730: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2731: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2732: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2733: error_fr(r, "compose");
1.367 djm 2734: channel_free(ssh, c);
1.354 markus 2735: goto out;
2736: }
2737: break;
2738: case SSH2_MSG_GLOBAL_REQUEST:
2739: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 2740: error_f("alloc");
1.354 markus 2741: goto out;
2742: }
2743: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 2744: error_fr(r, "parse");
1.354 markus 2745: goto out;
2746: }
2747: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 2748: error_f("unsupported request %s", ctype);
1.354 markus 2749: goto out;
2750: }
2751: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2752: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2753: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 2754: error_fr(r, "parse");
1.354 markus 2755: goto out;
2756: }
1.355 djm 2757: if (listen_port > 65535) {
1.403 djm 2758: error_f("tcpip-forward for %s: bad port %u",
2759: listen_host, listen_port);
1.355 djm 2760: goto out;
2761: }
1.354 markus 2762: /* Record that connection to this host/port is permitted. */
1.381 djm 2763: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2764: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2765: listen_host = NULL;
2766: break;
2767: case SSH2_MSG_CHANNEL_CLOSE:
2768: if (have < 4)
2769: break;
2770: remote_id = PEEK_U32(cp);
1.367 djm 2771: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2772: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2773: channel_free(ssh, c);
1.354 markus 2774: else
2775: c->flags |= CHAN_CLOSE_SENT;
2776: }
2777: break;
2778: }
2779: if (modified) {
2780: if ((r = sshpkt_start(ssh, type)) != 0 ||
2781: (r = sshpkt_putb(ssh, modified)) != 0 ||
2782: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2783: error_fr(r, "send");
1.354 markus 2784: goto out;
2785: }
2786: } else {
2787: if ((r = sshpkt_start(ssh, type)) != 0 ||
2788: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2789: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2790: error_fr(r, "send");
1.354 markus 2791: goto out;
2792: }
2793: }
2794: ret = 0;
2795: out:
2796: free(ctype);
2797: free(listen_host);
2798: sshbuf_free(original);
2799: sshbuf_free(modified);
2800: return ret;
2801: }
2802:
2803: /*
2804: * receive packets from upstream server and de-multiplex packets
2805: * to correct downstream:
2806: * implemented as a helper for channel input handlers,
2807: * replaces local (proxy) channel ID with downstream channel ID.
2808: */
2809: int
1.363 markus 2810: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 2811: {
2812: struct sshbuf *b = NULL;
2813: Channel *downstream;
2814: const u_char *cp = NULL;
2815: size_t len;
2816: int r;
2817:
2818: /*
2819: * When receiving packets from the peer we need to check whether we
2820: * need to forward the packets to the mux client. In this case we
1.380 djm 2821: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 2822: * so we can cleanup the channel.
2823: */
2824: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
2825: return 0;
2826: if ((downstream = c->mux_ctx) == NULL)
2827: return 0;
2828: switch (type) {
2829: case SSH2_MSG_CHANNEL_CLOSE:
2830: case SSH2_MSG_CHANNEL_DATA:
2831: case SSH2_MSG_CHANNEL_EOF:
2832: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
2833: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2834: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
2835: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
2836: case SSH2_MSG_CHANNEL_SUCCESS:
2837: case SSH2_MSG_CHANNEL_FAILURE:
2838: case SSH2_MSG_CHANNEL_REQUEST:
2839: break;
2840: default:
1.403 djm 2841: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 2842: return 0;
2843: }
2844: if ((b = sshbuf_new()) == NULL) {
1.403 djm 2845: error_f("alloc reply");
1.354 markus 2846: goto out;
2847: }
2848: /* get remaining payload (after id) */
2849: cp = sshpkt_ptr(ssh, &len);
2850: if (cp == NULL) {
1.403 djm 2851: error_f("no packet");
1.354 markus 2852: goto out;
2853: }
2854: /* translate id and send to muxclient */
2855: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
2856: (r = sshbuf_put_u8(b, type)) != 0 ||
2857: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
2858: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 2859: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 2860: error_fr(r, "compose muxclient");
1.354 markus 2861: goto out;
2862: }
2863: /* sshbuf_dump(b, stderr); */
2864: if (ssh_packet_log_type(type))
1.403 djm 2865: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 2866: out:
2867: /* update state */
2868: switch (type) {
2869: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2870: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 2871: if (cp && len > 4) {
1.354 markus 2872: c->remote_id = PEEK_U32(cp);
1.368 djm 2873: c->have_remote_id = 1;
2874: }
1.354 markus 2875: break;
2876: case SSH2_MSG_CHANNEL_CLOSE:
2877: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 2878: channel_free(ssh, c);
1.354 markus 2879: else
2880: c->flags |= CHAN_CLOSE_RCVD;
2881: break;
2882: }
2883: sshbuf_free(b);
2884: return 1;
2885: }
1.121 markus 2886:
2887: /* -- protocol input */
1.249 djm 2888:
1.367 djm 2889: /* Parse a channel ID from the current packet */
2890: static int
2891: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
2892: {
2893: u_int32_t id;
2894: int r;
2895:
2896: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 2897: error_r(r, "%s: parse id", where);
1.367 djm 2898: ssh_packet_disconnect(ssh, "Invalid %s message", what);
2899: }
2900: if (id > INT_MAX) {
1.403 djm 2901: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 2902: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
2903: }
2904: return (int)id;
2905: }
2906:
2907: /* Lookup a channel from an ID in the current packet */
2908: static Channel *
2909: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
2910: {
2911: int id = channel_parse_id(ssh, where, what);
2912: Channel *c;
2913:
2914: if ((c = channel_lookup(ssh, id)) == NULL) {
2915: ssh_packet_disconnect(ssh,
2916: "%s packet referred to nonexistent channel %d", what, id);
2917: }
2918: return c;
2919: }
2920:
1.339 markus 2921: int
1.363 markus 2922: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 2923: {
1.332 djm 2924: const u_char *data;
1.367 djm 2925: size_t data_len, win_len;
2926: Channel *c = channel_from_packet_id(ssh, __func__, "data");
2927: int r;
1.25 markus 2928:
1.363 markus 2929: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2930: return 0;
1.25 markus 2931:
2932: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 2933: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 2934: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
2935: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 2936: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 2937: return 0;
1.37 markus 2938:
1.25 markus 2939: /* Get the data. */
1.389 djm 2940: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
2941: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 2942: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 2943:
1.309 djm 2944: win_len = data_len;
2945: if (c->datagram)
2946: win_len += 4; /* string length header */
1.200 markus 2947:
2948: /*
1.367 djm 2949: * The sending side reduces its window as it sends data, so we
2950: * must 'fake' consumption of the data in order to ensure that window
2951: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 2952: */
1.358 djm 2953: if (c->ostate != CHAN_OUTPUT_OPEN) {
2954: c->local_window -= win_len;
2955: c->local_consumed += win_len;
1.339 markus 2956: return 0;
1.200 markus 2957: }
1.41 markus 2958:
1.358 djm 2959: if (win_len > c->local_maxpacket) {
1.367 djm 2960: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 2961: c->self, win_len, c->local_maxpacket);
1.367 djm 2962: return 0;
1.358 djm 2963: }
2964: if (win_len > c->local_window) {
1.367 djm 2965: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 2966: c->self, win_len, c->local_window);
2967: return 0;
1.44 markus 2968: }
1.358 djm 2969: c->local_window -= win_len;
2970:
1.367 djm 2971: if (c->datagram) {
2972: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 2973: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 2974: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 2975: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 2976:
1.339 markus 2977: return 0;
1.1 deraadt 2978: }
1.121 markus 2979:
1.339 markus 2980: int
1.363 markus 2981: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 2982: {
1.367 djm 2983: const u_char *data;
2984: size_t data_len;
2985: u_int32_t tcode;
2986: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
2987: int r;
1.44 markus 2988:
1.363 markus 2989: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 2990: return 0;
1.44 markus 2991: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 2992: logit("channel %d: ext data for non open", c->self);
1.339 markus 2993: return 0;
1.172 markus 2994: }
2995: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 2996: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 2997: debug("channel %d: accepting ext data after eof",
2998: c->self);
1.172 markus 2999: else
1.367 djm 3000: ssh_packet_disconnect(ssh, "Received extended_data "
3001: "after EOF on channel %d.", c->self);
3002: }
3003:
3004: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3005: error_fr(r, "parse tcode");
1.367 djm 3006: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3007: }
3008: if (c->efd == -1 ||
3009: c->extended_usage != CHAN_EXTENDED_WRITE ||
3010: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3011: logit("channel %d: bad ext data", c->self);
1.339 markus 3012: return 0;
1.44 markus 3013: }
1.389 djm 3014: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3015: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3016: error_fr(r, "parse data");
1.367 djm 3017: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3018: }
3019:
1.44 markus 3020: if (data_len > c->local_window) {
1.367 djm 3021: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3022: c->self, data_len, c->local_window);
1.339 markus 3023: return 0;
1.44 markus 3024: }
1.367 djm 3025: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3026: /* XXX sshpkt_getb? */
3027: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3028: error_fr(r, "append");
1.44 markus 3029: c->local_window -= data_len;
1.339 markus 3030: return 0;
1.44 markus 3031: }
3032:
1.339 markus 3033: int
1.363 markus 3034: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3035: {
1.367 djm 3036: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3037: int r;
1.367 djm 3038:
1.389 djm 3039: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3040: error_fr(r, "parse data");
1.389 djm 3041: ssh_packet_disconnect(ssh, "Invalid ieof message");
3042: }
1.41 markus 3043:
1.363 markus 3044: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3045: return 0;
1.367 djm 3046: chan_rcvd_ieof(ssh, c);
1.133 markus 3047:
3048: /* XXX force input close */
1.156 markus 3049: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3050: debug("channel %d: FORCE input drain", c->self);
3051: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3052: if (sshbuf_len(c->input) == 0)
3053: chan_ibuf_empty(ssh, c);
1.133 markus 3054: }
1.339 markus 3055: return 0;
1.41 markus 3056: }
1.1 deraadt 3057:
1.339 markus 3058: int
1.363 markus 3059: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3060: {
1.367 djm 3061: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3062: int r;
1.151 markus 3063:
1.363 markus 3064: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3065: return 0;
1.389 djm 3066: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3067: error_fr(r, "parse data");
1.389 djm 3068: ssh_packet_disconnect(ssh, "Invalid oclose message");
3069: }
1.367 djm 3070: chan_rcvd_oclose(ssh, c);
1.339 markus 3071: return 0;
1.1 deraadt 3072: }
3073:
1.339 markus 3074: int
1.363 markus 3075: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3076: {
1.367 djm 3077: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3078: u_int32_t remote_window, remote_maxpacket;
3079: int r;
1.25 markus 3080:
1.363 markus 3081: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3082: return 0;
3083: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3084: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3085: "non-opening channel %d.", c->self);
3086: /*
3087: * Record the remote channel number and mark that the channel
3088: * is now open.
3089: */
1.368 djm 3090: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3091: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3092: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3093: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3094: error_fr(r, "window/maxpacket");
1.389 djm 3095: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3096: }
3097:
1.368 djm 3098: c->have_remote_id = 1;
1.367 djm 3099: c->remote_window = remote_window;
3100: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3101: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3102: if (c->open_confirm) {
1.403 djm 3103: debug2_f("channel %d: callback start", c->self);
1.367 djm 3104: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3105: debug2_f("channel %d: callback done", c->self);
1.44 markus 3106: }
1.358 djm 3107: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3108: c->remote_window, c->remote_maxpacket);
1.339 markus 3109: return 0;
1.1 deraadt 3110: }
3111:
1.127 itojun 3112: static char *
1.114 markus 3113: reason2txt(int reason)
3114: {
1.143 deraadt 3115: switch (reason) {
1.114 markus 3116: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3117: return "administratively prohibited";
3118: case SSH2_OPEN_CONNECT_FAILED:
3119: return "connect failed";
3120: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3121: return "unknown channel type";
3122: case SSH2_OPEN_RESOURCE_SHORTAGE:
3123: return "resource shortage";
3124: }
1.117 stevesk 3125: return "unknown reason";
1.114 markus 3126: }
3127:
1.339 markus 3128: int
1.363 markus 3129: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3130: {
1.367 djm 3131: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3132: u_int32_t reason;
3133: char *msg = NULL;
3134: int r;
1.25 markus 3135:
1.363 markus 3136: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3137: return 0;
3138: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3139: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3140: "non-opening channel %d.", c->self);
3141: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3142: error_fr(r, "parse reason");
1.389 djm 3143: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3144: }
1.378 djm 3145: /* skip language */
3146: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3147: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3148: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3149: error_fr(r, "parse msg/lang");
1.389 djm 3150: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3151: }
1.367 djm 3152: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3153: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3154: free(msg);
3155: if (c->open_confirm) {
1.403 djm 3156: debug2_f("channel %d: callback start", c->self);
1.367 djm 3157: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3158: debug2_f("channel %d: callback done", c->self);
1.44 markus 3159: }
1.291 djm 3160: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3161: chan_mark_dead(ssh, c);
1.339 markus 3162: return 0;
1.44 markus 3163: }
3164:
1.339 markus 3165: int
1.363 markus 3166: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3167: {
1.367 djm 3168: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3169: Channel *c;
1.367 djm 3170: u_int32_t adjust;
3171: u_int new_rwin;
3172: int r;
1.1 deraadt 3173:
1.367 djm 3174: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3175: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3176: return 0;
1.372 markus 3177: }
1.367 djm 3178:
1.363 markus 3179: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3180: return 0;
1.389 djm 3181: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3182: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3183: error_fr(r, "parse adjust");
1.389 djm 3184: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3185: }
3186: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3187: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3188: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3189: c->self, adjust, c->remote_window);
3190: }
3191: c->remote_window = new_rwin;
1.339 markus 3192: return 0;
1.121 markus 3193: }
1.1 deraadt 3194:
1.339 markus 3195: int
1.363 markus 3196: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3197: {
1.367 djm 3198: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3199: Channel *c;
3200: struct channel_confirm *cc;
3201:
3202: /* Reset keepalive timeout */
1.389 djm 3203: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3204:
1.403 djm 3205: debug2_f("type %d id %d", type, id);
1.275 djm 3206:
1.367 djm 3207: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3208: logit_f("%d: unknown", id);
1.339 markus 3209: return 0;
1.367 djm 3210: }
1.363 markus 3211: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3212: return 0;
1.394 dtucker 3213: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3214: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3215: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3216: return 0;
1.367 djm 3217: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3218: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3219: freezero(cc, sizeof(*cc));
1.339 markus 3220: return 0;
1.275 djm 3221: }
1.121 markus 3222:
3223: /* -- tcp forwarding */
1.135 markus 3224:
3225: void
1.367 djm 3226: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3227: {
1.367 djm 3228: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3229: }
1.121 markus 3230:
1.312 djm 3231:
3232: /*
3233: * Determine whether or not a port forward listens to loopback, the
3234: * specified address or wildcard. On the client, a specified bind
3235: * address will always override gateway_ports. On the server, a
3236: * gateway_ports of 1 (``yes'') will override the client's specification
3237: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3238: * will bind to whatever address the client asked for.
3239: *
3240: * Special-case listen_addrs are:
3241: *
3242: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3243: * "" (empty string), "*" -> wildcard v4/v6
3244: * "localhost" -> loopback v4/v6
1.334 djm 3245: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3246: */
3247: static const char *
1.389 djm 3248: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3249: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3250: {
3251: const char *addr = NULL;
3252: int wildcard = 0;
3253:
3254: if (listen_addr == NULL) {
3255: /* No address specified: default to gateway_ports setting */
1.336 millert 3256: if (fwd_opts->gateway_ports)
1.312 djm 3257: wildcard = 1;
1.336 millert 3258: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3259: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3260: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3261: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3262: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3263: wildcard = 1;
1.326 djm 3264: /*
3265: * Notify client if they requested a specific listen
3266: * address and it was overridden.
3267: */
3268: if (*listen_addr != '\0' &&
3269: strcmp(listen_addr, "0.0.0.0") != 0 &&
3270: strcmp(listen_addr, "*") != 0) {
1.389 djm 3271: ssh_packet_send_debug(ssh,
3272: "Forwarding listen address "
1.326 djm 3273: "\"%s\" overridden by server "
3274: "GatewayPorts", listen_addr);
3275: }
1.334 djm 3276: } else if (strcmp(listen_addr, "localhost") != 0 ||
3277: strcmp(listen_addr, "127.0.0.1") == 0 ||
3278: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3279: /*
3280: * Accept explicit localhost address when
3281: * GatewayPorts=yes. The "localhost" hostname is
3282: * deliberately skipped here so it will listen on all
3283: * available local address families.
3284: */
1.334 djm 3285: addr = listen_addr;
1.326 djm 3286: }
1.334 djm 3287: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3288: strcmp(listen_addr, "::1") == 0) {
3289: /*
3290: * If a specific IPv4/IPv6 localhost address has been
3291: * requested then accept it even if gateway_ports is in
3292: * effect. This allows the client to prefer IPv4 or IPv6.
3293: */
3294: addr = listen_addr;
1.312 djm 3295: }
3296: if (wildcardp != NULL)
3297: *wildcardp = wildcard;
3298: return addr;
3299: }
3300:
1.160 markus 3301: static int
1.367 djm 3302: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3303: struct Forward *fwd, int *allocated_listen_port,
3304: struct ForwardOptions *fwd_opts)
1.25 markus 3305: {
1.113 markus 3306: Channel *c;
1.226 djm 3307: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3308: struct addrinfo hints, *ai, *aitop;
1.212 djm 3309: const char *host, *addr;
1.35 markus 3310: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3311: in_port_t *lport_p;
1.25 markus 3312:
1.212 djm 3313: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3314:
1.344 millert 3315: if (is_client && fwd->connect_path != NULL) {
3316: host = fwd->connect_path;
3317: } else {
3318: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3319: fwd->listen_host : fwd->connect_host;
3320: if (host == NULL) {
3321: error("No forward host name.");
3322: return 0;
3323: }
3324: if (strlen(host) >= NI_MAXHOST) {
3325: error("Forward host name too long.");
3326: return 0;
3327: }
1.87 markus 3328: }
1.25 markus 3329:
1.312 djm 3330: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3331: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3332: is_client, fwd_opts);
1.403 djm 3333: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3334: (addr == NULL) ? "NULL" : addr);
1.212 djm 3335:
3336: /*
1.35 markus 3337: * getaddrinfo returns a loopback address if the hostname is
3338: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3339: */
1.35 markus 3340: memset(&hints, 0, sizeof(hints));
1.367 djm 3341: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3342: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3343: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3344: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3345: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3346: if (addr == NULL) {
3347: /* This really shouldn't happen */
1.389 djm 3348: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3349: ssh_gai_strerror(r));
1.212 djm 3350: } else {
1.403 djm 3351: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3352: ssh_gai_strerror(r));
1.212 djm 3353: }
1.218 markus 3354: return 0;
1.212 djm 3355: }
1.295 djm 3356: if (allocated_listen_port != NULL)
3357: *allocated_listen_port = 0;
1.35 markus 3358: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3359: switch (ai->ai_family) {
3360: case AF_INET:
3361: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3362: sin_port;
3363: break;
3364: case AF_INET6:
3365: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3366: sin6_port;
3367: break;
3368: default:
1.35 markus 3369: continue;
1.295 djm 3370: }
3371: /*
3372: * If allocating a port for -R forwards, then use the
3373: * same port for all address families.
3374: */
1.367 djm 3375: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3376: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3377: *allocated_listen_port > 0)
1.295 djm 3378: *lport_p = htons(*allocated_listen_port);
3379:
1.35 markus 3380: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3381: strport, sizeof(strport),
3382: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3383: error_f("getnameinfo failed");
1.35 markus 3384: continue;
3385: }
3386: /* Create a port to listen for the host. */
1.300 dtucker 3387: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3388: if (sock == -1) {
1.35 markus 3389: /* this is no error since kernel may not support ipv6 */
1.377 djm 3390: verbose("socket [%s]:%s: %.100s", ntop, strport,
3391: strerror(errno));
1.35 markus 3392: continue;
3393: }
1.226 djm 3394:
1.376 djm 3395: set_reuseaddr(sock);
1.182 stevesk 3396:
1.295 djm 3397: debug("Local forwarding listening on %s port %s.",
3398: ntop, strport);
1.35 markus 3399:
3400: /* Bind the socket to the address. */
1.393 deraadt 3401: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3402: /*
3403: * address can be in if use ipv6 address is
3404: * already bound
3405: */
1.377 djm 3406: verbose("bind [%s]:%s: %.100s",
3407: ntop, strport, strerror(errno));
1.35 markus 3408: close(sock);
3409: continue;
3410: }
3411: /* Start listening for connections on the socket. */
1.393 deraadt 3412: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3413: error("listen [%s]:%s: %.100s", ntop, strport,
3414: strerror(errno));
1.35 markus 3415: close(sock);
3416: continue;
3417: }
1.295 djm 3418:
3419: /*
1.336 millert 3420: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3421: * record what we got.
3422: */
1.367 djm 3423: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3424: fwd->listen_port == 0 &&
1.295 djm 3425: allocated_listen_port != NULL &&
3426: *allocated_listen_port == 0) {
1.350 djm 3427: *allocated_listen_port = get_local_port(sock);
1.295 djm 3428: debug("Allocated listen port %d",
3429: *allocated_listen_port);
3430: }
3431:
1.35 markus 3432: /* Allocate a channel number for the socket. */
1.367 djm 3433: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3434: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3435: 0, "port listener", 1);
1.293 djm 3436: c->path = xstrdup(host);
1.336 millert 3437: c->host_port = fwd->connect_port;
1.312 djm 3438: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3439: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3440: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3441: c->listening_port = *allocated_listen_port;
3442: else
1.336 millert 3443: c->listening_port = fwd->listen_port;
1.35 markus 3444: success = 1;
3445: }
3446: if (success == 0)
1.403 djm 3447: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3448: freeaddrinfo(aitop);
1.87 markus 3449: return success;
1.25 markus 3450: }
1.1 deraadt 3451:
1.336 millert 3452: static int
1.367 djm 3453: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3454: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3455: {
3456: struct sockaddr_un sunaddr;
3457: const char *path;
3458: Channel *c;
3459: int port, sock;
3460: mode_t omask;
3461:
3462: switch (type) {
3463: case SSH_CHANNEL_UNIX_LISTENER:
3464: if (fwd->connect_path != NULL) {
3465: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3466: error("Local connecting path too long: %s",
3467: fwd->connect_path);
3468: return 0;
3469: }
3470: path = fwd->connect_path;
3471: port = PORT_STREAMLOCAL;
3472: } else {
3473: if (fwd->connect_host == NULL) {
3474: error("No forward host name.");
3475: return 0;
3476: }
3477: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3478: error("Forward host name too long.");
3479: return 0;
3480: }
3481: path = fwd->connect_host;
3482: port = fwd->connect_port;
3483: }
3484: break;
3485: case SSH_CHANNEL_RUNIX_LISTENER:
3486: path = fwd->listen_path;
3487: port = PORT_STREAMLOCAL;
3488: break;
3489: default:
1.403 djm 3490: error_f("unexpected channel type %d", type);
1.336 millert 3491: return 0;
3492: }
3493:
3494: if (fwd->listen_path == NULL) {
3495: error("No forward path name.");
3496: return 0;
3497: }
3498: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3499: error("Local listening path too long: %s", fwd->listen_path);
3500: return 0;
3501: }
3502:
1.403 djm 3503: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3504:
3505: /* Start a Unix domain listener. */
3506: omask = umask(fwd_opts->streamlocal_bind_mask);
3507: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3508: fwd_opts->streamlocal_bind_unlink);
3509: umask(omask);
3510: if (sock < 0)
3511: return 0;
3512:
3513: debug("Local forwarding listening on path %s.", fwd->listen_path);
3514:
3515: /* Allocate a channel number for the socket. */
1.367 djm 3516: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3517: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3518: 0, "unix listener", 1);
3519: c->path = xstrdup(path);
3520: c->host_port = port;
3521: c->listening_port = PORT_STREAMLOCAL;
3522: c->listening_addr = xstrdup(fwd->listen_path);
3523: return 1;
3524: }
3525:
3526: static int
1.367 djm 3527: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3528: const char *host, u_short port)
1.202 djm 3529: {
1.209 avsm 3530: u_int i;
3531: int found = 0;
1.202 djm 3532:
1.367 djm 3533: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3534: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3535: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3536: continue;
3537: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3538: debug2_f("close channel %d", i);
1.367 djm 3539: channel_free(ssh, c);
1.312 djm 3540: found = 1;
3541: }
3542: }
3543:
1.367 djm 3544: return found;
1.312 djm 3545: }
3546:
1.336 millert 3547: static int
1.367 djm 3548: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3549: {
3550: u_int i;
3551: int found = 0;
3552:
1.367 djm 3553: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3554: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3555: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3556: continue;
3557: if (c->path == NULL)
3558: continue;
3559: if (strcmp(c->path, path) == 0) {
1.403 djm 3560: debug2_f("close channel %d", i);
1.367 djm 3561: channel_free(ssh, c);
1.336 millert 3562: found = 1;
3563: }
3564: }
3565:
1.367 djm 3566: return found;
1.336 millert 3567: }
3568:
1.312 djm 3569: int
1.367 djm 3570: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3571: {
1.367 djm 3572: if (fwd->listen_path != NULL) {
3573: return channel_cancel_rport_listener_streamlocal(ssh,
3574: fwd->listen_path);
3575: } else {
3576: return channel_cancel_rport_listener_tcpip(ssh,
3577: fwd->listen_host, fwd->listen_port);
3578: }
1.336 millert 3579: }
3580:
3581: static int
1.367 djm 3582: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3583: const char *lhost, u_short lport, int cport,
3584: struct ForwardOptions *fwd_opts)
1.312 djm 3585: {
3586: u_int i;
3587: int found = 0;
1.389 djm 3588: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3589:
1.367 djm 3590: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3591: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3592: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3593: continue;
1.313 markus 3594: if (c->listening_port != lport)
1.312 djm 3595: continue;
1.313 markus 3596: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3597: /* skip dynamic forwardings */
3598: if (c->host_port == 0)
3599: continue;
3600: } else {
3601: if (c->host_port != cport)
3602: continue;
3603: }
1.312 djm 3604: if ((c->listening_addr == NULL && addr != NULL) ||
3605: (c->listening_addr != NULL && addr == NULL))
3606: continue;
3607: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 3608: debug2_f("close channel %d", i);
1.367 djm 3609: channel_free(ssh, c);
1.202 djm 3610: found = 1;
3611: }
3612: }
3613:
1.367 djm 3614: return found;
1.202 djm 3615: }
3616:
1.336 millert 3617: static int
1.367 djm 3618: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3619: {
3620: u_int i;
3621: int found = 0;
3622:
3623: if (path == NULL) {
1.403 djm 3624: error_f("no path specified.");
1.336 millert 3625: return 0;
3626: }
3627:
1.367 djm 3628: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3629: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3630: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3631: continue;
3632: if (c->listening_addr == NULL)
3633: continue;
3634: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 3635: debug2_f("close channel %d", i);
1.367 djm 3636: channel_free(ssh, c);
1.336 millert 3637: found = 1;
3638: }
3639: }
3640:
1.367 djm 3641: return found;
1.336 millert 3642: }
3643:
3644: int
1.367 djm 3645: channel_cancel_lport_listener(struct ssh *ssh,
3646: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3647: {
1.367 djm 3648: if (fwd->listen_path != NULL) {
3649: return channel_cancel_lport_listener_streamlocal(ssh,
3650: fwd->listen_path);
3651: } else {
3652: return channel_cancel_lport_listener_tcpip(ssh,
3653: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3654: }
1.336 millert 3655: }
3656:
1.362 markus 3657: /* protocol local port fwd, used by ssh */
1.160 markus 3658: int
1.367 djm 3659: channel_setup_local_fwd_listener(struct ssh *ssh,
3660: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3661: {
1.336 millert 3662: if (fwd->listen_path != NULL) {
1.367 djm 3663: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3664: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3665: } else {
1.367 djm 3666: return channel_setup_fwd_listener_tcpip(ssh,
3667: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3668: }
1.160 markus 3669: }
3670:
1.381 djm 3671: /* Matches a remote forwarding permission against a requested forwarding */
3672: static int
3673: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3674: {
3675: int ret;
3676: char *lhost;
3677:
3678: /* XXX add ACLs for streamlocal */
3679: if (fwd->listen_path != NULL)
3680: return 1;
3681:
3682: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3683: return 0;
3684:
3685: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3686: allowed_open->listen_port != fwd->listen_port)
3687: return 0;
3688:
3689: /* Match hostnames case-insensitively */
3690: lhost = xstrdup(fwd->listen_host);
3691: lowercase(lhost);
3692: ret = match_pattern(lhost, allowed_open->listen_host);
3693: free(lhost);
3694:
3695: return ret;
3696: }
3697:
3698: /* Checks whether a requested remote forwarding is permitted */
3699: static int
3700: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3701: {
3702: struct ssh_channels *sc = ssh->chanctxt;
3703: struct permission_set *pset = &sc->remote_perms;
3704: u_int i, permit, permit_adm = 1;
3705: struct permission *perm;
3706:
3707: /* XXX apply GatewayPorts override before checking? */
3708:
3709: permit = pset->all_permitted;
3710: if (!permit) {
3711: for (i = 0; i < pset->num_permitted_user; i++) {
3712: perm = &pset->permitted_user[i];
3713: if (remote_open_match(perm, fwd)) {
3714: permit = 1;
3715: break;
3716: }
3717: }
3718: }
3719:
3720: if (pset->num_permitted_admin > 0) {
3721: permit_adm = 0;
3722: for (i = 0; i < pset->num_permitted_admin; i++) {
3723: perm = &pset->permitted_admin[i];
3724: if (remote_open_match(perm, fwd)) {
3725: permit_adm = 1;
3726: break;
3727: }
3728: }
3729: }
3730:
3731: return permit && permit_adm;
3732: }
3733:
1.160 markus 3734: /* protocol v2 remote port fwd, used by sshd */
3735: int
1.367 djm 3736: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3737: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3738: {
1.381 djm 3739: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3740: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3741: if (fwd->listen_path != NULL)
3742: /* XXX always allowed, see remote_open_match() */
3743: logit("Received request from %.100s port %d to "
3744: "remote forward to path \"%.100s\", "
3745: "but the request was denied.",
3746: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3747: fwd->listen_path);
3748: else if(fwd->listen_host != NULL)
3749: logit("Received request from %.100s port %d to "
3750: "remote forward to host %.100s port %d, "
3751: "but the request was denied.",
3752: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3753: fwd->listen_host, fwd->listen_port );
3754: else
3755: logit("Received request from %.100s port %d to remote "
3756: "forward, but the request was denied.",
3757: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3758: return 0;
3759: }
1.336 millert 3760: if (fwd->listen_path != NULL) {
1.367 djm 3761: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3762: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3763: } else {
1.367 djm 3764: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3765: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3766: fwd_opts);
3767: }
1.160 markus 3768: }
3769:
1.27 markus 3770: /*
1.312 djm 3771: * Translate the requested rfwd listen host to something usable for
3772: * this server.
3773: */
3774: static const char *
3775: channel_rfwd_bind_host(const char *listen_host)
3776: {
3777: if (listen_host == NULL) {
1.378 djm 3778: return "localhost";
1.312 djm 3779: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 3780: return "";
1.312 djm 3781: } else
3782: return listen_host;
3783: }
3784:
3785: /*
1.27 markus 3786: * Initiate forwarding of connections to port "port" on remote host through
3787: * the secure channel to host:port from local side.
1.315 markus 3788: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 3789: * channel_update_permission().
1.27 markus 3790: */
1.253 markus 3791: int
1.367 djm 3792: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3793: {
1.367 djm 3794: int r, success = 0, idx = -1;
3795: char *host_to_connect, *listen_host, *listen_path;
3796: int port_to_connect, listen_port;
1.73 markus 3797:
1.25 markus 3798: /* Send the forward request to the remote side. */
1.358 djm 3799: if (fwd->listen_path != NULL) {
1.367 djm 3800: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3801: (r = sshpkt_put_cstring(ssh,
3802: "streamlocal-forward@openssh.com")) != 0 ||
3803: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3804: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3805: (r = sshpkt_send(ssh)) != 0 ||
3806: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 3807: fatal_fr(r, "request streamlocal");
1.336 millert 3808: } else {
1.367 djm 3809: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3810: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
3811: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3812: (r = sshpkt_put_cstring(ssh,
3813: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
3814: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
3815: (r = sshpkt_send(ssh)) != 0 ||
3816: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 3817: fatal_fr(r, "request tcpip-forward");
1.73 markus 3818: }
1.358 djm 3819: /* Assume that server accepts the request */
3820: success = 1;
1.73 markus 3821: if (success) {
1.305 djm 3822: /* Record that connection to this host/port is permitted. */
1.367 djm 3823: host_to_connect = listen_host = listen_path = NULL;
3824: port_to_connect = listen_port = 0;
1.336 millert 3825: if (fwd->connect_path != NULL) {
1.367 djm 3826: host_to_connect = xstrdup(fwd->connect_path);
3827: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 3828: } else {
1.367 djm 3829: host_to_connect = xstrdup(fwd->connect_host);
3830: port_to_connect = fwd->connect_port;
1.336 millert 3831: }
3832: if (fwd->listen_path != NULL) {
1.367 djm 3833: listen_path = xstrdup(fwd->listen_path);
3834: listen_port = PORT_STREAMLOCAL;
1.336 millert 3835: } else {
1.367 djm 3836: if (fwd->listen_host != NULL)
3837: listen_host = xstrdup(fwd->listen_host);
3838: listen_port = fwd->listen_port;
3839: }
1.381 djm 3840: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 3841: host_to_connect, port_to_connect,
3842: listen_host, listen_path, listen_port, NULL);
1.44 markus 3843: }
1.367 djm 3844: return idx;
1.1 deraadt 3845: }
3846:
1.333 markus 3847: static int
1.381 djm 3848: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 3849: int requestedport)
1.333 markus 3850: {
3851: if (allowed_open->host_to_connect == NULL)
3852: return 0;
3853: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
3854: allowed_open->port_to_connect != requestedport)
3855: return 0;
1.351 dtucker 3856: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
3857: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 3858: return 0;
3859: return 1;
3860: }
3861:
3862: /*
1.336 millert 3863: * Note that in the listen host/port case
1.333 markus 3864: * we don't support FWD_PERMIT_ANY_PORT and
3865: * need to translate between the configured-host (listen_host)
3866: * and what we've sent to the remote server (channel_rfwd_bind_host)
3867: */
3868: static int
1.381 djm 3869: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 3870: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 3871: {
3872: const char *allowed_host;
3873:
3874: if (allowed_open->host_to_connect == NULL)
3875: return 0;
3876: if (allowed_open->listen_port != requestedport)
3877: return 0;
1.335 djm 3878: if (!translate && allowed_open->listen_host == NULL &&
3879: requestedhost == NULL)
3880: return 1;
1.333 markus 3881: allowed_host = translate ?
3882: channel_rfwd_bind_host(allowed_open->listen_host) :
3883: allowed_open->listen_host;
1.382 djm 3884: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 3885: strcmp(allowed_host, requestedhost) != 0)
3886: return 0;
3887: return 1;
3888: }
3889:
1.336 millert 3890: static int
1.381 djm 3891: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 3892: const char *requestedpath)
3893: {
3894: if (allowed_open->host_to_connect == NULL)
3895: return 0;
3896: if (allowed_open->listen_port != PORT_STREAMLOCAL)
3897: return 0;
3898: if (allowed_open->listen_path == NULL ||
3899: strcmp(allowed_open->listen_path, requestedpath) != 0)
3900: return 0;
3901: return 1;
3902: }
3903:
1.27 markus 3904: /*
1.208 deraadt 3905: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 3906: * local side.
3907: */
1.336 millert 3908: static int
1.367 djm 3909: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
3910: const char *host, u_short port)
1.202 djm 3911: {
1.367 djm 3912: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3913: struct permission_set *pset = &sc->local_perms;
1.367 djm 3914: int r;
3915: u_int i;
1.397 markus 3916: struct permission *perm = NULL;
1.202 djm 3917:
1.381 djm 3918: for (i = 0; i < pset->num_permitted_user; i++) {
3919: perm = &pset->permitted_user[i];
3920: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 3921: break;
1.381 djm 3922: perm = NULL;
1.202 djm 3923: }
1.381 djm 3924: if (perm == NULL) {
1.403 djm 3925: debug_f("requested forward not found");
1.312 djm 3926: return -1;
1.202 djm 3927: }
1.367 djm 3928: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3929: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
3930: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3931: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
3932: (r = sshpkt_put_u32(ssh, port)) != 0 ||
3933: (r = sshpkt_send(ssh)) != 0)
1.403 djm 3934: fatal_fr(r, "send cancel");
1.367 djm 3935:
1.381 djm 3936: fwd_perm_clear(perm); /* unregister */
1.336 millert 3937:
3938: return 0;
3939: }
3940:
3941: /*
3942: * Request cancellation of remote forwarding of Unix domain socket
3943: * path from local side.
3944: */
3945: static int
1.367 djm 3946: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3947: {
1.367 djm 3948: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 3949: struct permission_set *pset = &sc->local_perms;
1.367 djm 3950: int r;
3951: u_int i;
1.397 markus 3952: struct permission *perm = NULL;
1.336 millert 3953:
1.381 djm 3954: for (i = 0; i < pset->num_permitted_user; i++) {
3955: perm = &pset->permitted_user[i];
3956: if (open_listen_match_streamlocal(perm, path))
1.336 millert 3957: break;
1.381 djm 3958: perm = NULL;
1.336 millert 3959: }
1.381 djm 3960: if (perm == NULL) {
1.403 djm 3961: debug_f("requested forward not found");
1.336 millert 3962: return -1;
3963: }
1.367 djm 3964: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3965: (r = sshpkt_put_cstring(ssh,
3966: "cancel-streamlocal-forward@openssh.com")) != 0 ||
3967: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
3968: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
3969: (r = sshpkt_send(ssh)) != 0)
1.403 djm 3970: fatal_fr(r, "send cancel");
1.367 djm 3971:
1.381 djm 3972: fwd_perm_clear(perm); /* unregister */
1.312 djm 3973:
3974: return 0;
1.202 djm 3975: }
3976:
3977: /*
1.336 millert 3978: * Request cancellation of remote forwarding of a connection from local side.
3979: */
3980: int
1.367 djm 3981: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3982: {
3983: if (fwd->listen_path != NULL) {
1.367 djm 3984: return channel_request_rforward_cancel_streamlocal(ssh,
3985: fwd->listen_path);
1.336 millert 3986: } else {
1.367 djm 3987: return channel_request_rforward_cancel_tcpip(ssh,
3988: fwd->listen_host,
3989: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 3990: }
1.1 deraadt 3991: }
3992:
1.99 markus 3993: /*
1.381 djm 3994: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 3995: * usually called by the server, because the user could connect to any port
3996: * anyway, and the server has no way to know but to trust the client anyway.
3997: */
3998: void
1.381 djm 3999: channel_permit_all(struct ssh *ssh, int where)
4000: {
4001: struct permission_set *pset = permission_set_get(ssh, where);
4002:
4003: if (pset->num_permitted_user == 0)
4004: pset->all_permitted = 1;
4005: }
4006:
4007: /*
4008: * Permit the specified host/port for forwarding.
4009: */
4010: void
4011: channel_add_permission(struct ssh *ssh, int who, int where,
4012: char *host, int port)
4013: {
4014: int local = where == FORWARD_LOCAL;
4015: struct permission_set *pset = permission_set_get(ssh, where);
4016:
4017: debug("allow %s forwarding to host %s port %d",
4018: fwd_ident(who, where), host, port);
4019: /*
4020: * Remote forwards set listen_host/port, local forwards set
4021: * host/port_to_connect.
4022: */
4023: permission_set_add(ssh, who, where,
4024: local ? host : 0, local ? port : 0,
4025: local ? NULL : host, NULL, local ? 0 : port, NULL);
4026: pset->all_permitted = 0;
4027: }
4028:
4029: /*
4030: * Administratively disable forwarding.
4031: */
4032: void
4033: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4034: {
1.381 djm 4035: channel_clear_permission(ssh, FORWARD_ADM, where);
4036: permission_set_add(ssh, FORWARD_ADM, where,
4037: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4038: }
4039:
1.381 djm 4040: /*
4041: * Clear a list of permitted opens.
4042: */
1.101 markus 4043: void
1.381 djm 4044: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4045: {
1.381 djm 4046: struct permission **permp;
4047: u_int *npermp;
1.367 djm 4048:
1.381 djm 4049: permission_set_get_array(ssh, who, where, &permp, &npermp);
4050: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4051: *npermp = 0;
1.315 markus 4052: }
4053:
4054: /*
4055: * Update the listen port for a dynamic remote forward, after
4056: * the actual 'newport' has been allocated. If 'newport' < 0 is
4057: * passed then they entry will be invalidated.
4058: */
4059: void
1.381 djm 4060: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4061: {
1.381 djm 4062: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4063:
1.381 djm 4064: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4065: debug_f("index out of range: %d num_permitted_user %d",
4066: idx, pset->num_permitted_user);
1.315 markus 4067: return;
4068: }
4069: debug("%s allowed port %d for forwarding to host %s port %d",
4070: newport > 0 ? "Updating" : "Removing",
4071: newport,
1.381 djm 4072: pset->permitted_user[idx].host_to_connect,
4073: pset->permitted_user[idx].port_to_connect);
1.367 djm 4074: if (newport <= 0)
1.381 djm 4075: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4076: else {
1.381 djm 4077: pset->permitted_user[idx].listen_port =
1.404 djm 4078: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4079: }
1.99 markus 4080: }
4081:
1.314 dtucker 4082: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4083: int
4084: permitopen_port(const char *p)
4085: {
4086: int port;
4087:
4088: if (strcmp(p, "*") == 0)
4089: return FWD_PERMIT_ANY_PORT;
4090: if ((port = a2port(p)) > 0)
4091: return port;
4092: return -1;
4093: }
4094:
1.276 djm 4095: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4096: static int
1.276 djm 4097: connect_next(struct channel_connect *cctx)
1.41 markus 4098: {
1.276 djm 4099: int sock, saved_errno;
1.336 millert 4100: struct sockaddr_un *sunaddr;
1.367 djm 4101: char ntop[NI_MAXHOST];
4102: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4103:
1.276 djm 4104: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4105: switch (cctx->ai->ai_family) {
4106: case AF_UNIX:
4107: /* unix:pathname instead of host:port */
4108: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4109: strlcpy(ntop, "unix", sizeof(ntop));
4110: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4111: break;
4112: case AF_INET:
4113: case AF_INET6:
4114: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4115: ntop, sizeof(ntop), strport, sizeof(strport),
4116: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4117: error("connect_next: getnameinfo failed");
4118: continue;
4119: }
4120: break;
4121: default:
1.41 markus 4122: continue;
4123: }
1.300 dtucker 4124: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4125: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4126: if (cctx->ai->ai_next == NULL)
1.186 djm 4127: error("socket: %.100s", strerror(errno));
4128: else
4129: verbose("socket: %.100s", strerror(errno));
1.41 markus 4130: continue;
4131: }
1.205 djm 4132: if (set_nonblock(sock) == -1)
1.403 djm 4133: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4134: if (connect(sock, cctx->ai->ai_addr,
4135: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4136: debug("connect_next: host %.100s ([%.100s]:%s): "
4137: "%.100s", cctx->host, ntop, strport,
1.41 markus 4138: strerror(errno));
1.276 djm 4139: saved_errno = errno;
1.41 markus 4140: close(sock);
1.276 djm 4141: errno = saved_errno;
1.89 stevesk 4142: continue; /* fail -- try next */
1.41 markus 4143: }
1.336 millert 4144: if (cctx->ai->ai_family != AF_UNIX)
4145: set_nodelay(sock);
1.276 djm 4146: debug("connect_next: host %.100s ([%.100s]:%s) "
4147: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4148: cctx->ai = cctx->ai->ai_next;
4149: return sock;
4150: }
4151: return -1;
4152: }
1.41 markus 4153:
1.276 djm 4154: static void
4155: channel_connect_ctx_free(struct channel_connect *cctx)
4156: {
1.321 djm 4157: free(cctx->host);
1.336 millert 4158: if (cctx->aitop) {
4159: if (cctx->aitop->ai_family == AF_UNIX)
4160: free(cctx->aitop);
4161: else
4162: freeaddrinfo(cctx->aitop);
4163: }
1.329 tedu 4164: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4165: }
4166:
1.357 dtucker 4167: /*
1.372 markus 4168: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4169: * passing back the failure reason if appropriate.
4170: */
1.372 markus 4171: static int
4172: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4173: char *ctype, char *rname, struct channel_connect *cctx,
4174: int *reason, const char **errmsg)
1.276 djm 4175: {
4176: struct addrinfo hints;
4177: int gaierr;
4178: int sock = -1;
4179: char strport[NI_MAXSERV];
1.336 millert 4180:
4181: if (port == PORT_STREAMLOCAL) {
4182: struct sockaddr_un *sunaddr;
4183: struct addrinfo *ai;
4184:
4185: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4186: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4187: return -1;
1.336 millert 4188: }
4189:
4190: /*
4191: * Fake up a struct addrinfo for AF_UNIX connections.
4192: * channel_connect_ctx_free() must check ai_family
4193: * and use free() not freeaddirinfo() for AF_UNIX.
4194: */
4195: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4196: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4197: ai->ai_addr = (struct sockaddr *)(ai + 1);
4198: ai->ai_addrlen = sizeof(*sunaddr);
4199: ai->ai_family = AF_UNIX;
1.372 markus 4200: ai->ai_socktype = socktype;
1.336 millert 4201: ai->ai_protocol = PF_UNSPEC;
4202: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4203: sunaddr->sun_family = AF_UNIX;
4204: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4205: cctx->aitop = ai;
1.336 millert 4206: } else {
4207: memset(&hints, 0, sizeof(hints));
1.367 djm 4208: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4209: hints.ai_socktype = socktype;
1.336 millert 4210: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4211: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4212: != 0) {
4213: if (errmsg != NULL)
4214: *errmsg = ssh_gai_strerror(gaierr);
4215: if (reason != NULL)
4216: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4217: error("connect_to %.100s: unknown host (%s)", name,
4218: ssh_gai_strerror(gaierr));
1.372 markus 4219: return -1;
1.336 millert 4220: }
1.41 markus 4221: }
1.276 djm 4222:
1.372 markus 4223: cctx->host = xstrdup(name);
4224: cctx->port = port;
4225: cctx->ai = cctx->aitop;
1.276 djm 4226:
1.372 markus 4227: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4228: error("connect to %.100s port %d failed: %s",
1.336 millert 4229: name, port, strerror(errno));
1.372 markus 4230: return -1;
4231: }
4232:
4233: return sock;
4234: }
4235:
4236: /* Return CONNECTING channel to remote host:port or local socket path */
4237: static Channel *
4238: connect_to(struct ssh *ssh, const char *host, int port,
4239: char *ctype, char *rname)
4240: {
4241: struct channel_connect cctx;
4242: Channel *c;
4243: int sock;
4244:
4245: memset(&cctx, 0, sizeof(cctx));
4246: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4247: &cctx, NULL, NULL);
4248: if (sock == -1) {
1.276 djm 4249: channel_connect_ctx_free(&cctx);
4250: return NULL;
1.41 markus 4251: }
1.367 djm 4252: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4253: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4254: c->host_port = port;
4255: c->path = xstrdup(host);
1.276 djm 4256: c->connect_ctx = cctx;
1.372 markus 4257:
1.276 djm 4258: return c;
1.41 markus 4259: }
1.99 markus 4260:
1.354 markus 4261: /*
4262: * returns either the newly connected channel or the downstream channel
4263: * that needs to deal with this connection.
4264: */
1.276 djm 4265: Channel *
1.367 djm 4266: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4267: u_short listen_port, char *ctype, char *rname)
1.73 markus 4268: {
1.367 djm 4269: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4270: struct permission_set *pset = &sc->local_perms;
1.367 djm 4271: u_int i;
1.381 djm 4272: struct permission *perm;
1.99 markus 4273:
1.381 djm 4274: for (i = 0; i < pset->num_permitted_user; i++) {
4275: perm = &pset->permitted_user[i];
4276: if (open_listen_match_tcpip(perm,
4277: listen_host, listen_port, 1)) {
4278: if (perm->downstream)
4279: return perm->downstream;
4280: if (perm->port_to_connect == 0)
1.372 markus 4281: return rdynamic_connect_prepare(ssh,
4282: ctype, rname);
1.367 djm 4283: return connect_to(ssh,
1.381 djm 4284: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4285: ctype, rname);
1.276 djm 4286: }
4287: }
1.74 markus 4288: error("WARNING: Server requests forwarding for unknown listen_port %d",
4289: listen_port);
1.276 djm 4290: return NULL;
1.73 markus 4291: }
4292:
1.336 millert 4293: Channel *
1.367 djm 4294: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4295: char *ctype, char *rname)
1.336 millert 4296: {
1.367 djm 4297: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4298: struct permission_set *pset = &sc->local_perms;
1.367 djm 4299: u_int i;
1.381 djm 4300: struct permission *perm;
1.336 millert 4301:
1.381 djm 4302: for (i = 0; i < pset->num_permitted_user; i++) {
4303: perm = &pset->permitted_user[i];
4304: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4305: return connect_to(ssh,
1.381 djm 4306: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4307: ctype, rname);
1.336 millert 4308: }
4309: }
4310: error("WARNING: Server requests forwarding for unknown path %.100s",
4311: path);
4312: return NULL;
4313: }
4314:
1.99 markus 4315: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4316: Channel *
1.367 djm 4317: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4318: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4319: {
1.367 djm 4320: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4321: struct permission_set *pset = &sc->local_perms;
1.372 markus 4322: struct channel_connect cctx;
4323: Channel *c;
1.367 djm 4324: u_int i, permit, permit_adm = 1;
1.372 markus 4325: int sock;
1.381 djm 4326: struct permission *perm;
1.99 markus 4327:
1.381 djm 4328: permit = pset->all_permitted;
1.99 markus 4329: if (!permit) {
1.381 djm 4330: for (i = 0; i < pset->num_permitted_user; i++) {
4331: perm = &pset->permitted_user[i];
4332: if (open_match(perm, host, port)) {
1.99 markus 4333: permit = 1;
1.333 markus 4334: break;
4335: }
1.367 djm 4336: }
1.257 dtucker 4337: }
1.99 markus 4338:
1.381 djm 4339: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4340: permit_adm = 0;
1.381 djm 4341: for (i = 0; i < pset->num_permitted_admin; i++) {
4342: perm = &pset->permitted_admin[i];
4343: if (open_match(perm, host, port)) {
1.257 dtucker 4344: permit_adm = 1;
1.333 markus 4345: break;
4346: }
1.367 djm 4347: }
1.99 markus 4348: }
1.257 dtucker 4349:
4350: if (!permit || !permit_adm) {
1.391 florian 4351: logit("Received request from %.100s port %d to connect to "
4352: "host %.100s port %d, but the request was denied.",
4353: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4354: if (reason != NULL)
4355: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4356: return NULL;
1.99 markus 4357: }
1.372 markus 4358:
4359: memset(&cctx, 0, sizeof(cctx));
4360: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4361: &cctx, reason, errmsg);
4362: if (sock == -1) {
4363: channel_connect_ctx_free(&cctx);
4364: return NULL;
4365: }
4366:
4367: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4368: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4369: c->host_port = port;
4370: c->path = xstrdup(host);
4371: c->connect_ctx = cctx;
4372:
4373: return c;
1.336 millert 4374: }
4375:
4376: /* Check if connecting to that path is permitted and connect. */
4377: Channel *
1.367 djm 4378: channel_connect_to_path(struct ssh *ssh, const char *path,
4379: char *ctype, char *rname)
1.336 millert 4380: {
1.367 djm 4381: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4382: struct permission_set *pset = &sc->local_perms;
1.367 djm 4383: u_int i, permit, permit_adm = 1;
1.381 djm 4384: struct permission *perm;
1.336 millert 4385:
1.381 djm 4386: permit = pset->all_permitted;
1.336 millert 4387: if (!permit) {
1.381 djm 4388: for (i = 0; i < pset->num_permitted_user; i++) {
4389: perm = &pset->permitted_user[i];
4390: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4391: permit = 1;
4392: break;
4393: }
1.367 djm 4394: }
1.336 millert 4395: }
4396:
1.381 djm 4397: if (pset->num_permitted_admin > 0) {
1.336 millert 4398: permit_adm = 0;
1.381 djm 4399: for (i = 0; i < pset->num_permitted_admin; i++) {
4400: perm = &pset->permitted_admin[i];
4401: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4402: permit_adm = 1;
4403: break;
4404: }
1.367 djm 4405: }
1.336 millert 4406: }
4407:
4408: if (!permit || !permit_adm) {
4409: logit("Received request to connect to path %.100s, "
4410: "but the request was denied.", path);
4411: return NULL;
4412: }
1.367 djm 4413: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4414: }
4415:
4416: void
1.367 djm 4417: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4418: {
1.367 djm 4419: struct ssh_channels *sc = ssh->chanctxt;
4420: struct winsize ws;
4421: int r;
1.209 avsm 4422: u_int i;
1.204 djm 4423:
1.367 djm 4424: for (i = 0; i < sc->channels_alloc; i++) {
4425: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4426: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4427: continue;
1.393 deraadt 4428: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4429: continue;
1.367 djm 4430: channel_request_start(ssh, i, "window-change", 0);
4431: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4432: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4433: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4434: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4435: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4436: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4437: }
1.372 markus 4438: }
4439:
4440: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4441: static Channel *
4442: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4443: {
4444: Channel *c;
4445: int r;
4446:
4447: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4448: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4449: c->host_port = 0;
4450: c->path = NULL;
4451:
4452: /*
4453: * We need to open the channel before we have a FD,
4454: * so that we can get SOCKS header from peer.
4455: */
4456: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4457: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4458: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4459: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4460: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4461: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4462: return c;
4463: }
4464:
4465: /* Return CONNECTING socket to remote host:port or local socket path */
4466: static int
4467: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4468: {
1.405 markus 4469: struct ssh_channels *sc = ssh->chanctxt;
4470: struct permission_set *pset = &sc->local_perms;
4471: struct permission *perm;
1.372 markus 4472: struct channel_connect cctx;
1.405 markus 4473: u_int i, permit_adm = 1;
1.372 markus 4474: int sock;
1.405 markus 4475:
4476: if (pset->num_permitted_admin > 0) {
4477: permit_adm = 0;
4478: for (i = 0; i < pset->num_permitted_admin; i++) {
4479: perm = &pset->permitted_admin[i];
4480: if (open_match(perm, c->path, c->host_port)) {
4481: permit_adm = 1;
4482: break;
4483: }
4484: }
4485: }
4486: if (!permit_adm) {
4487: debug_f("requested forward not permitted");
4488: return -1;
4489: }
1.372 markus 4490:
4491: memset(&cctx, 0, sizeof(cctx));
4492: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4493: NULL, &cctx, NULL, NULL);
4494: if (sock == -1)
4495: channel_connect_ctx_free(&cctx);
4496: else {
4497: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4498: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4499: c->connect_ctx = cctx;
4500: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4501: }
4502: return sock;
1.99 markus 4503: }
4504:
1.121 markus 4505: /* -- X11 forwarding */
1.1 deraadt 4506:
1.27 markus 4507: /*
4508: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4509: * Returns 0 and a suitable display number for the DISPLAY variable
4510: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4511: */
1.141 stevesk 4512: int
1.367 djm 4513: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4514: int x11_use_localhost, int single_connection,
4515: u_int *display_numberp, int **chanids)
1.1 deraadt 4516: {
1.149 markus 4517: Channel *nc = NULL;
1.31 markus 4518: int display_number, sock;
4519: u_short port;
1.35 markus 4520: struct addrinfo hints, *ai, *aitop;
4521: char strport[NI_MAXSERV];
4522: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4523:
1.224 markus 4524: if (chanids == NULL)
4525: return -1;
4526:
1.33 markus 4527: for (display_number = x11_display_offset;
1.148 deraadt 4528: display_number < MAX_DISPLAYS;
4529: display_number++) {
1.25 markus 4530: port = 6000 + display_number;
1.35 markus 4531: memset(&hints, 0, sizeof(hints));
1.367 djm 4532: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4533: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4534: hints.ai_socktype = SOCK_STREAM;
4535: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4536: if ((gaierr = getaddrinfo(NULL, strport,
4537: &hints, &aitop)) != 0) {
1.271 dtucker 4538: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4539: return -1;
1.25 markus 4540: }
1.35 markus 4541: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4542: if (ai->ai_family != AF_INET &&
4543: ai->ai_family != AF_INET6)
1.35 markus 4544: continue;
1.300 dtucker 4545: sock = socket(ai->ai_family, ai->ai_socktype,
4546: ai->ai_protocol);
1.393 deraadt 4547: if (sock == -1) {
1.35 markus 4548: error("socket: %.100s", strerror(errno));
1.203 markus 4549: freeaddrinfo(aitop);
1.141 stevesk 4550: return -1;
1.35 markus 4551: }
1.376 djm 4552: set_reuseaddr(sock);
1.393 deraadt 4553: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4554: debug2_f("bind port %d: %.100s", port,
4555: strerror(errno));
1.35 markus 4556: close(sock);
1.367 djm 4557: for (n = 0; n < num_socks; n++)
1.35 markus 4558: close(socks[n]);
4559: num_socks = 0;
4560: break;
4561: }
4562: socks[num_socks++] = sock;
4563: if (num_socks == NUM_SOCKS)
4564: break;
1.25 markus 4565: }
1.83 stevesk 4566: freeaddrinfo(aitop);
1.35 markus 4567: if (num_socks > 0)
4568: break;
1.25 markus 4569: }
4570: if (display_number >= MAX_DISPLAYS) {
4571: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4572: return -1;
1.25 markus 4573: }
4574: /* Start listening for connections on the socket. */
1.35 markus 4575: for (n = 0; n < num_socks; n++) {
4576: sock = socks[n];
1.393 deraadt 4577: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4578: error("listen: %.100s", strerror(errno));
4579: close(sock);
1.141 stevesk 4580: return -1;
1.35 markus 4581: }
1.25 markus 4582: }
1.35 markus 4583:
4584: /* Allocate a channel for each socket. */
1.242 djm 4585: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4586: for (n = 0; n < num_socks; n++) {
4587: sock = socks[n];
1.367 djm 4588: nc = channel_new(ssh, "x11 listener",
1.51 markus 4589: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4590: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4591: 0, "X11 inet listener", 1);
1.167 markus 4592: nc->single_connection = single_connection;
1.224 markus 4593: (*chanids)[n] = nc->self;
1.35 markus 4594: }
1.224 markus 4595: (*chanids)[n] = -1;
1.1 deraadt 4596:
1.141 stevesk 4597: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4598: *display_numberp = display_number;
1.367 djm 4599: return 0;
1.1 deraadt 4600: }
4601:
1.127 itojun 4602: static int
1.77 markus 4603: connect_local_xsocket(u_int dnr)
1.1 deraadt 4604: {
1.25 markus 4605: int sock;
4606: struct sockaddr_un addr;
4607:
1.147 stevesk 4608: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4609: if (sock == -1)
1.147 stevesk 4610: error("socket: %.100s", strerror(errno));
4611: memset(&addr, 0, sizeof(addr));
4612: addr.sun_family = AF_UNIX;
4613: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4614: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4615: return sock;
4616: close(sock);
1.25 markus 4617: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4618: return -1;
1.1 deraadt 4619: }
4620:
1.51 markus 4621: int
1.367 djm 4622: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4623: {
1.248 deraadt 4624: u_int display_number;
1.25 markus 4625: const char *display;
1.51 markus 4626: char buf[1024], *cp;
1.35 markus 4627: struct addrinfo hints, *ai, *aitop;
4628: char strport[NI_MAXSERV];
1.248 deraadt 4629: int gaierr, sock = 0;
1.25 markus 4630:
4631: /* Try to open a socket for the local X server. */
4632: display = getenv("DISPLAY");
4633: if (!display) {
4634: error("DISPLAY not set.");
1.51 markus 4635: return -1;
1.25 markus 4636: }
1.27 markus 4637: /*
4638: * Now we decode the value of the DISPLAY variable and make a
4639: * connection to the real X server.
4640: */
4641:
4642: /*
4643: * Check if it is a unix domain socket. Unix domain displays are in
4644: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4645: */
1.25 markus 4646: if (strncmp(display, "unix:", 5) == 0 ||
4647: display[0] == ':') {
4648: /* Connect to the unix domain socket. */
1.367 djm 4649: if (sscanf(strrchr(display, ':') + 1, "%u",
4650: &display_number) != 1) {
4651: error("Could not parse display number from DISPLAY: "
4652: "%.100s", display);
1.51 markus 4653: return -1;
1.25 markus 4654: }
4655: /* Create a socket. */
4656: sock = connect_local_xsocket(display_number);
4657: if (sock < 0)
1.51 markus 4658: return -1;
1.25 markus 4659:
4660: /* OK, we now have a connection to the display. */
1.51 markus 4661: return sock;
1.25 markus 4662: }
1.27 markus 4663: /*
4664: * Connect to an inet socket. The DISPLAY value is supposedly
4665: * hostname:d[.s], where hostname may also be numeric IP address.
4666: */
1.145 stevesk 4667: strlcpy(buf, display, sizeof(buf));
1.25 markus 4668: cp = strchr(buf, ':');
4669: if (!cp) {
4670: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4671: return -1;
1.25 markus 4672: }
4673: *cp = 0;
1.367 djm 4674: /*
4675: * buf now contains the host name. But first we parse the
4676: * display number.
4677: */
1.248 deraadt 4678: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4679: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4680: display);
1.51 markus 4681: return -1;
1.25 markus 4682: }
1.35 markus 4683:
4684: /* Look up the host address */
4685: memset(&hints, 0, sizeof(hints));
1.367 djm 4686: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4687: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4688: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4689: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4690: error("%.100s: unknown host. (%s)", buf,
4691: ssh_gai_strerror(gaierr));
1.51 markus 4692: return -1;
1.25 markus 4693: }
1.35 markus 4694: for (ai = aitop; ai; ai = ai->ai_next) {
4695: /* Create a socket. */
1.300 dtucker 4696: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 4697: if (sock == -1) {
1.194 markus 4698: debug2("socket: %.100s", strerror(errno));
1.41 markus 4699: continue;
4700: }
4701: /* Connect it to the display. */
1.393 deraadt 4702: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4703: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4704: 6000 + display_number, strerror(errno));
4705: close(sock);
4706: continue;
4707: }
4708: /* Success */
4709: break;
1.35 markus 4710: }
4711: freeaddrinfo(aitop);
4712: if (!ai) {
1.367 djm 4713: error("connect %.100s port %u: %.100s", buf,
4714: 6000 + display_number, strerror(errno));
1.51 markus 4715: return -1;
1.25 markus 4716: }
1.162 stevesk 4717: set_nodelay(sock);
1.51 markus 4718: return sock;
4719: }
4720:
4721: /*
1.27 markus 4722: * Requests forwarding of X11 connections, generates fake authentication
4723: * data, and enables authentication spoofing.
1.121 markus 4724: * This should be called in the client only.
1.27 markus 4725: */
1.49 markus 4726: void
1.367 djm 4727: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4728: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4729: {
1.367 djm 4730: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4731: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4732: u_int i, value;
1.367 djm 4733: const char *cp;
1.25 markus 4734: char *new_data;
1.367 djm 4735: int r, screen_number;
1.25 markus 4736:
1.367 djm 4737: if (sc->x11_saved_display == NULL)
4738: sc->x11_saved_display = xstrdup(disp);
4739: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4740: error("x11_request_forwarding_with_spoofing: different "
4741: "$DISPLAY already forwarded");
4742: return;
4743: }
4744:
1.266 djm 4745: cp = strchr(disp, ':');
1.25 markus 4746: if (cp)
4747: cp = strchr(cp, '.');
4748: if (cp)
1.245 deraadt 4749: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4750: else
4751: screen_number = 0;
4752:
1.367 djm 4753: if (sc->x11_saved_proto == NULL) {
1.219 djm 4754: /* Save protocol name. */
1.367 djm 4755: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4756:
4757: /* Extract real authentication data. */
1.367 djm 4758: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4759: for (i = 0; i < data_len; i++) {
1.403 djm 4760: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 4761: fatal("x11_request_forwarding: bad "
4762: "authentication data: %.100s", data);
1.403 djm 4763: }
1.367 djm 4764: sc->x11_saved_data[i] = value;
1.219 djm 4765: }
1.367 djm 4766: sc->x11_saved_data_len = data_len;
1.353 natano 4767:
4768: /* Generate fake data of the same length. */
1.367 djm 4769: sc->x11_fake_data = xmalloc(data_len);
4770: arc4random_buf(sc->x11_fake_data, data_len);
4771: sc->x11_fake_data_len = data_len;
1.25 markus 4772: }
4773:
4774: /* Convert the fake data into hex. */
1.367 djm 4775: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4776:
4777: /* Send the request packet. */
1.367 djm 4778: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4779: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4780: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4781: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4782: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4783: (r = sshpkt_send(ssh)) != 0 ||
4784: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4785: fatal_fr(r, "send x11-req");
1.321 djm 4786: free(new_data);
1.1 deraadt 4787: }
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