Annotation of src/usr.bin/ssh/channels.c, Revision 1.411
1.411 ! djm 1: /* $OpenBSD: channels.c,v 1.410 2022/01/06 21:46:23 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>
1.411 ! djm 57: #include <poll.h>
1.367 djm 58: #include <stdarg.h>
1.341 millert 59: #include <stdint.h>
1.263 stevesk 60: #include <stdio.h>
1.262 stevesk 61: #include <stdlib.h>
1.260 stevesk 62: #include <string.h>
1.233 stevesk 63: #include <termios.h>
1.256 stevesk 64: #include <unistd.h>
1.1 deraadt 65:
1.265 deraadt 66: #include "xmalloc.h"
1.1 deraadt 67: #include "ssh.h"
1.82 markus 68: #include "ssh2.h"
1.354 markus 69: #include "ssherr.h"
1.367 djm 70: #include "sshbuf.h"
1.1 deraadt 71: #include "packet.h"
1.82 markus 72: #include "log.h"
73: #include "misc.h"
1.14 markus 74: #include "channels.h"
75: #include "compat.h"
1.82 markus 76: #include "canohost.h"
1.383 markus 77: #include "sshkey.h"
1.64 markus 78: #include "authfd.h"
1.147 stevesk 79: #include "pathnames.h"
1.381 djm 80: #include "match.h"
1.388 djm 81:
1.411 ! djm 82: /* XXX remove once we're satisfied there's no lurking bugs */
! 83: /* #define DEBUG_CHANNEL_POLL 1 */
! 84:
1.367 djm 85: /* -- agent forwarding */
86: #define NUM_SOCKS 10
1.12 markus 87:
1.367 djm 88: /* -- tcp forwarding */
89: /* special-case port number meaning allow any port */
90: #define FWD_PERMIT_ANY_PORT 0
1.1 deraadt 91:
1.367 djm 92: /* special-case wildcard meaning allow any host */
93: #define FWD_PERMIT_ANY_HOST "*"
1.1 deraadt 94:
1.367 djm 95: /* -- X11 forwarding */
96: /* Maximum number of fake X11 displays to try. */
97: #define MAX_DISPLAYS 1000
1.1 deraadt 98:
1.411 ! djm 99: /* Per-channel callback for pre/post IO actions */
1.410 djm 100: typedef void chan_fn(struct ssh *, Channel *c);
1.381 djm 101:
1.27 markus 102: /*
103: * Data structure for storing which hosts are permitted for forward requests.
104: * The local sides of any remote forwards are stored in this array to prevent
105: * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
106: * network (which might be behind a firewall).
107: */
1.336 millert 108: /* XXX: streamlocal wants a path instead of host:port */
109: /* Overload host_to_connect; we could just make this match Forward */
110: /* XXX - can we use listen_host instead of listen_path? */
1.381 djm 111: struct permission {
1.41 markus 112: char *host_to_connect; /* Connect to 'host'. */
1.336 millert 113: int port_to_connect; /* Connect to 'port'. */
1.333 markus 114: char *listen_host; /* Remote side should listen address. */
1.336 millert 115: char *listen_path; /* Remote side should listen path. */
116: int listen_port; /* Remote side should listen port. */
1.354 markus 117: Channel *downstream; /* Downstream mux*/
1.381 djm 118: };
119:
120: /*
121: * Stores the forwarding permission state for a single direction (local or
122: * remote).
123: */
124: struct permission_set {
125: /*
126: * List of all local permitted host/port pairs to allow for the
127: * user.
128: */
129: u_int num_permitted_user;
130: struct permission *permitted_user;
1.1 deraadt 131:
1.381 djm 132: /*
133: * List of all permitted host/port pairs to allow for the admin.
134: */
135: u_int num_permitted_admin;
136: struct permission *permitted_admin;
137:
138: /*
139: * If this is true, all opens/listens are permitted. This is the
140: * case on the server on which we have to trust the client anyway,
141: * and the user could do anything after logging in.
142: */
143: int all_permitted;
144: };
1.121 markus 145:
1.367 djm 146: /* Master structure for channels state */
147: struct ssh_channels {
148: /*
149: * Pointer to an array containing all allocated channels. The array
150: * is dynamically extended as needed.
151: */
152: Channel **channels;
1.257 dtucker 153:
1.367 djm 154: /*
155: * Size of the channel array. All slots of the array must always be
156: * initialized (at least the type field); unused slots set to NULL
157: */
158: u_int channels_alloc;
1.257 dtucker 159:
1.367 djm 160: /*
1.411 ! djm 161: * 'channel_pre*' are called just before IO to add any bits
! 162: * relevant to channels in the c->io_want bitmasks.
1.367 djm 163: *
164: * 'channel_post*': perform any appropriate operations for
1.411 ! djm 165: * channels which have c->io_ready events pending.
1.367 djm 166: */
167: chan_fn **channel_pre;
168: chan_fn **channel_post;
1.314 dtucker 169:
1.367 djm 170: /* -- tcp forwarding */
1.381 djm 171: struct permission_set local_perms;
172: struct permission_set remote_perms;
1.219 djm 173:
1.367 djm 174: /* -- X11 forwarding */
1.121 markus 175:
1.367 djm 176: /* Saved X11 local (client) display. */
177: char *x11_saved_display;
1.121 markus 178:
1.367 djm 179: /* Saved X11 authentication protocol name. */
180: char *x11_saved_proto;
1.347 djm 181:
1.367 djm 182: /* Saved X11 authentication data. This is the real data. */
183: char *x11_saved_data;
184: u_int x11_saved_data_len;
1.121 markus 185:
1.367 djm 186: /* Deadline after which all X11 connections are refused */
187: u_int x11_refuse_time;
1.121 markus 188:
1.367 djm 189: /*
190: * Fake X11 authentication data. This is what the server will be
191: * sending us; we should replace any occurrences of this by the
192: * real data.
193: */
194: u_char *x11_fake_data;
195: u_int x11_fake_data_len;
1.121 markus 196:
1.367 djm 197: /* AF_UNSPEC or AF_INET or AF_INET6 */
198: int IPv4or6;
199: };
1.1 deraadt 200:
1.121 markus 201: /* helper */
1.367 djm 202: static void port_open_helper(struct ssh *ssh, Channel *c, char *rtype);
1.354 markus 203: static const char *channel_rfwd_bind_host(const char *listen_host);
1.103 markus 204:
1.276 djm 205: /* non-blocking connect helpers */
206: static int connect_next(struct channel_connect *);
207: static void channel_connect_ctx_free(struct channel_connect *);
1.372 markus 208: static Channel *rdynamic_connect_prepare(struct ssh *, char *, char *);
209: static int rdynamic_connect_finish(struct ssh *, Channel *);
1.276 djm 210:
1.367 djm 211: /* Setup helper */
212: static void channel_handler_init(struct ssh_channels *sc);
213:
1.121 markus 214: /* -- channel core */
1.41 markus 215:
1.367 djm 216: void
217: channel_init_channels(struct ssh *ssh)
218: {
219: struct ssh_channels *sc;
220:
1.387 djm 221: if ((sc = calloc(1, sizeof(*sc))) == NULL)
1.403 djm 222: fatal_f("allocation failed");
1.367 djm 223: sc->channels_alloc = 10;
224: sc->channels = xcalloc(sc->channels_alloc, sizeof(*sc->channels));
225: sc->IPv4or6 = AF_UNSPEC;
226: channel_handler_init(sc);
227:
228: ssh->chanctxt = sc;
229: }
230:
1.41 markus 231: Channel *
1.367 djm 232: channel_by_id(struct ssh *ssh, int id)
1.41 markus 233: {
234: Channel *c;
1.113 markus 235:
1.367 djm 236: if (id < 0 || (u_int)id >= ssh->chanctxt->channels_alloc) {
1.403 djm 237: logit_f("%d: bad id", id);
1.41 markus 238: return NULL;
239: }
1.367 djm 240: c = ssh->chanctxt->channels[id];
1.113 markus 241: if (c == NULL) {
1.403 djm 242: logit_f("%d: bad id: channel free", id);
1.41 markus 243: return NULL;
244: }
245: return c;
1.55 markus 246: }
247:
1.354 markus 248: Channel *
1.368 djm 249: channel_by_remote_id(struct ssh *ssh, u_int remote_id)
1.354 markus 250: {
251: Channel *c;
252: u_int i;
253:
1.367 djm 254: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
255: c = ssh->chanctxt->channels[i];
1.368 djm 256: if (c != NULL && c->have_remote_id && c->remote_id == remote_id)
1.354 markus 257: return c;
258: }
259: return NULL;
260: }
261:
1.27 markus 262: /*
1.229 markus 263: * Returns the channel if it is allowed to receive protocol messages.
264: * Private channels, like listening sockets, may not receive messages.
265: */
266: Channel *
1.367 djm 267: channel_lookup(struct ssh *ssh, int id)
1.229 markus 268: {
269: Channel *c;
270:
1.367 djm 271: if ((c = channel_by_id(ssh, id)) == NULL)
272: return NULL;
1.229 markus 273:
1.237 deraadt 274: switch (c->type) {
1.229 markus 275: case SSH_CHANNEL_X11_OPEN:
276: case SSH_CHANNEL_LARVAL:
277: case SSH_CHANNEL_CONNECTING:
278: case SSH_CHANNEL_DYNAMIC:
1.372 markus 279: case SSH_CHANNEL_RDYNAMIC_OPEN:
280: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.229 markus 281: case SSH_CHANNEL_OPENING:
282: case SSH_CHANNEL_OPEN:
1.323 dtucker 283: case SSH_CHANNEL_ABANDONED:
1.354 markus 284: case SSH_CHANNEL_MUX_PROXY:
1.367 djm 285: return c;
1.229 markus 286: }
287: logit("Non-public channel %d, type %d.", id, c->type);
1.367 djm 288: return NULL;
1.229 markus 289: }
290:
291: /*
1.55 markus 292: * Register filedescriptors for a channel, used when allocating a channel or
1.52 markus 293: * when the channel consumer/producer is ready, e.g. shell exec'd
1.27 markus 294: */
1.127 itojun 295: static void
1.367 djm 296: channel_register_fds(struct ssh *ssh, Channel *c, int rfd, int wfd, int efd,
1.282 dtucker 297: int extusage, int nonblock, int is_tty)
1.1 deraadt 298: {
1.298 dtucker 299: if (rfd != -1)
300: fcntl(rfd, F_SETFD, FD_CLOEXEC);
301: if (wfd != -1 && wfd != rfd)
302: fcntl(wfd, F_SETFD, FD_CLOEXEC);
303: if (efd != -1 && efd != rfd && efd != wfd)
304: fcntl(efd, F_SETFD, FD_CLOEXEC);
1.55 markus 305:
1.52 markus 306: c->rfd = rfd;
307: c->wfd = wfd;
308: c->sock = (rfd == wfd) ? rfd : -1;
309: c->efd = efd;
310: c->extended_usage = extusage;
1.71 markus 311:
1.282 dtucker 312: if ((c->isatty = is_tty) != 0)
1.194 markus 313: debug2("channel %d: rfd %d isatty", c->self, c->rfd);
1.91 markus 314:
1.71 markus 315: /* enable nonblocking mode */
1.407 djm 316: c->restore_block = 0;
317: if (nonblock == CHANNEL_NONBLOCK_STDIO) {
318: /*
319: * Special handling for stdio file descriptors: do not set
320: * non-blocking mode if they are TTYs. Otherwise prepare to
321: * restore their blocking state on exit to avoid interfering
322: * with other programs that follow.
323: */
324: if (rfd != -1 && !isatty(rfd) && fcntl(rfd, F_GETFL) == 0) {
325: c->restore_block |= CHANNEL_RESTORE_RFD;
326: set_nonblock(rfd);
327: }
328: if (wfd != -1 && !isatty(wfd) && fcntl(wfd, F_GETFL) == 0) {
329: c->restore_block |= CHANNEL_RESTORE_WFD;
330: set_nonblock(wfd);
331: }
332: if (efd != -1 && !isatty(efd) && fcntl(efd, F_GETFL) == 0) {
333: c->restore_block |= CHANNEL_RESTORE_EFD;
334: set_nonblock(efd);
335: }
336: } else if (nonblock) {
1.71 markus 337: if (rfd != -1)
338: set_nonblock(rfd);
339: if (wfd != -1)
340: set_nonblock(wfd);
341: if (efd != -1)
342: set_nonblock(efd);
343: }
1.52 markus 344: }
345:
346: /*
347: * Allocate a new channel object and set its type and socket. This will cause
348: * remote_name to be freed.
349: */
1.113 markus 350: Channel *
1.367 djm 351: channel_new(struct ssh *ssh, char *ctype, int type, int rfd, int wfd, int efd,
1.178 markus 352: u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
1.52 markus 353: {
1.367 djm 354: struct ssh_channels *sc = ssh->chanctxt;
355: u_int i, found;
1.52 markus 356: Channel *c;
1.402 djm 357: int r;
1.25 markus 358:
359: /* Try to find a free slot where to put the new channel. */
1.367 djm 360: for (i = 0; i < sc->channels_alloc; i++) {
361: if (sc->channels[i] == NULL) {
1.25 markus 362: /* Found a free slot. */
1.367 djm 363: found = i;
1.25 markus 364: break;
365: }
1.367 djm 366: }
367: if (i >= sc->channels_alloc) {
368: /*
369: * There are no free slots. Take last+1 slot and expand
370: * the array.
371: */
372: found = sc->channels_alloc;
373: if (sc->channels_alloc > CHANNELS_MAX_CHANNELS)
1.403 djm 374: fatal_f("internal error: channels_alloc %d too big",
375: sc->channels_alloc);
1.367 djm 376: sc->channels = xrecallocarray(sc->channels, sc->channels_alloc,
377: sc->channels_alloc + 10, sizeof(*sc->channels));
378: sc->channels_alloc += 10;
379: debug2("channel: expanding %d", sc->channels_alloc);
1.25 markus 380: }
1.113 markus 381: /* Initialize and return new channel. */
1.367 djm 382: c = sc->channels[found] = xcalloc(1, sizeof(Channel));
383: if ((c->input = sshbuf_new()) == NULL ||
384: (c->output = sshbuf_new()) == NULL ||
385: (c->extended = sshbuf_new()) == NULL)
1.403 djm 386: fatal_f("sshbuf_new failed");
1.402 djm 387: if ((r = sshbuf_set_max_size(c->input, CHAN_INPUT_MAX)) != 0)
1.403 djm 388: fatal_fr(r, "sshbuf_set_max_size");
1.159 markus 389: c->ostate = CHAN_OUTPUT_OPEN;
390: c->istate = CHAN_INPUT_OPEN;
1.367 djm 391: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, 0);
1.25 markus 392: c->self = found;
393: c->type = type;
1.41 markus 394: c->ctype = ctype;
1.51 markus 395: c->local_window = window;
396: c->local_window_max = window;
397: c->local_maxpacket = maxpack;
1.190 markus 398: c->remote_name = xstrdup(remote_name);
1.302 djm 399: c->ctl_chan = -1;
1.299 markus 400: c->delayed = 1; /* prevent call to channel_post handler */
1.275 djm 401: TAILQ_INIT(&c->status_confirms);
1.25 markus 402: debug("channel %d: new [%s]", found, remote_name);
1.113 markus 403: return c;
1.1 deraadt 404: }
1.52 markus 405:
1.132 markus 406: int
1.407 djm 407: channel_close_fd(struct ssh *ssh, Channel *c, int *fdp)
1.132 markus 408: {
1.407 djm 409: int ret, fd = *fdp;
1.132 markus 410:
1.407 djm 411: if (fd == -1)
412: return 0;
413:
414: if ((*fdp == c->rfd && (c->restore_block & CHANNEL_RESTORE_RFD) != 0) ||
415: (*fdp == c->wfd && (c->restore_block & CHANNEL_RESTORE_WFD) != 0) ||
416: (*fdp == c->efd && (c->restore_block & CHANNEL_RESTORE_EFD) != 0))
417: (void)fcntl(*fdp, F_SETFL, 0); /* restore blocking */
418:
1.411 ! djm 419: if (*fdp == c->rfd) {
! 420: c->io_want &= ~SSH_CHAN_IO_RFD;
! 421: c->io_ready &= ~SSH_CHAN_IO_RFD;
! 422: c->rfd = -1;
! 423: }
! 424: if (*fdp == c->wfd) {
! 425: c->io_want &= ~SSH_CHAN_IO_WFD;
! 426: c->io_ready &= ~SSH_CHAN_IO_WFD;
! 427: c->wfd = -1;
! 428: }
! 429: if (*fdp == c->efd) {
! 430: c->io_want &= ~SSH_CHAN_IO_EFD;
! 431: c->io_ready &= ~SSH_CHAN_IO_EFD;
! 432: c->efd = -1;
! 433: }
! 434: if (*fdp == c->sock) {
! 435: c->io_want &= ~SSH_CHAN_IO_SOCK;
! 436: c->io_ready &= ~SSH_CHAN_IO_SOCK;
! 437: c->sock = -1;
! 438: }
! 439:
1.407 djm 440: ret = close(fd);
1.411 ! djm 441: *fdp = -1; /* probably redundant */
1.132 markus 442: return ret;
443: }
444:
1.52 markus 445: /* Close all channel fd/socket. */
1.127 itojun 446: static void
1.367 djm 447: channel_close_fds(struct ssh *ssh, Channel *c)
448: {
1.379 tb 449: int sock = c->sock, rfd = c->rfd, wfd = c->wfd, efd = c->efd;
450:
1.407 djm 451: channel_close_fd(ssh, c, &c->sock);
1.379 tb 452: if (rfd != sock)
1.407 djm 453: channel_close_fd(ssh, c, &c->rfd);
1.379 tb 454: if (wfd != sock && wfd != rfd)
1.407 djm 455: channel_close_fd(ssh, c, &c->wfd);
1.379 tb 456: if (efd != sock && efd != rfd && efd != wfd)
1.407 djm 457: channel_close_fd(ssh, c, &c->efd);
1.367 djm 458: }
459:
460: static void
1.381 djm 461: fwd_perm_clear(struct permission *perm)
1.52 markus 462: {
1.381 djm 463: free(perm->host_to_connect);
464: free(perm->listen_host);
465: free(perm->listen_path);
1.398 dtucker 466: memset(perm, 0, sizeof(*perm));
1.367 djm 467: }
468:
1.381 djm 469: /* Returns an printable name for the specified forwarding permission list */
470: static const char *
471: fwd_ident(int who, int where)
472: {
473: if (who == FORWARD_ADM) {
474: if (where == FORWARD_LOCAL)
475: return "admin local";
476: else if (where == FORWARD_REMOTE)
477: return "admin remote";
478: } else if (who == FORWARD_USER) {
479: if (where == FORWARD_LOCAL)
480: return "user local";
481: else if (where == FORWARD_REMOTE)
482: return "user remote";
483: }
484: fatal("Unknown forward permission list %d/%d", who, where);
485: }
486:
487: /* Returns the forwarding permission list for the specified direction */
488: static struct permission_set *
489: permission_set_get(struct ssh *ssh, int where)
490: {
491: struct ssh_channels *sc = ssh->chanctxt;
1.367 djm 492:
1.381 djm 493: switch (where) {
494: case FORWARD_LOCAL:
495: return &sc->local_perms;
496: break;
497: case FORWARD_REMOTE:
498: return &sc->remote_perms;
499: break;
500: default:
1.403 djm 501: fatal_f("invalid forwarding direction %d", where);
1.381 djm 502: }
503: }
504:
1.392 dtucker 505: /* Returns pointers to the specified forwarding list and its element count */
1.381 djm 506: static void
507: permission_set_get_array(struct ssh *ssh, int who, int where,
508: struct permission ***permpp, u_int **npermpp)
509: {
510: struct permission_set *pset = permission_set_get(ssh, where);
511:
512: switch (who) {
513: case FORWARD_USER:
514: *permpp = &pset->permitted_user;
515: *npermpp = &pset->num_permitted_user;
516: break;
517: case FORWARD_ADM:
518: *permpp = &pset->permitted_admin;
519: *npermpp = &pset->num_permitted_admin;
520: break;
521: default:
1.403 djm 522: fatal_f("invalid forwarding client %d", who);
1.381 djm 523: }
524: }
525:
1.409 jsg 526: /* Adds an entry to the specified forwarding list */
1.367 djm 527: static int
1.381 djm 528: permission_set_add(struct ssh *ssh, int who, int where,
1.367 djm 529: const char *host_to_connect, int port_to_connect,
530: const char *listen_host, const char *listen_path, int listen_port,
531: Channel *downstream)
532: {
1.381 djm 533: struct permission **permp;
534: u_int n, *npermp;
1.367 djm 535:
1.381 djm 536: permission_set_get_array(ssh, who, where, &permp, &npermp);
1.367 djm 537:
1.381 djm 538: if (*npermp >= INT_MAX)
1.403 djm 539: fatal_f("%s overflow", fwd_ident(who, where));
1.367 djm 540:
1.381 djm 541: *permp = xrecallocarray(*permp, *npermp, *npermp + 1, sizeof(**permp));
542: n = (*npermp)++;
1.367 djm 543: #define MAYBE_DUP(s) ((s == NULL) ? NULL : xstrdup(s))
1.381 djm 544: (*permp)[n].host_to_connect = MAYBE_DUP(host_to_connect);
545: (*permp)[n].port_to_connect = port_to_connect;
546: (*permp)[n].listen_host = MAYBE_DUP(listen_host);
547: (*permp)[n].listen_path = MAYBE_DUP(listen_path);
548: (*permp)[n].listen_port = listen_port;
549: (*permp)[n].downstream = downstream;
1.367 djm 550: #undef MAYBE_DUP
551: return (int)n;
552: }
553:
554: static void
555: mux_remove_remote_forwardings(struct ssh *ssh, Channel *c)
556: {
557: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 558: struct permission_set *pset = &sc->local_perms;
559: struct permission *perm;
1.367 djm 560: int r;
561: u_int i;
562:
1.381 djm 563: for (i = 0; i < pset->num_permitted_user; i++) {
564: perm = &pset->permitted_user[i];
565: if (perm->downstream != c)
1.367 djm 566: continue;
567:
568: /* cancel on the server, since mux client is gone */
569: debug("channel %d: cleanup remote forward for %s:%u",
1.381 djm 570: c->self, perm->listen_host, perm->listen_port);
1.367 djm 571: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
572: (r = sshpkt_put_cstring(ssh,
573: "cancel-tcpip-forward")) != 0 ||
574: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
575: (r = sshpkt_put_cstring(ssh,
1.381 djm 576: channel_rfwd_bind_host(perm->listen_host))) != 0 ||
577: (r = sshpkt_put_u32(ssh, perm->listen_port)) != 0 ||
1.367 djm 578: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 579: fatal_fr(r, "channel %i", c->self);
1.367 djm 580: }
1.381 djm 581: fwd_perm_clear(perm); /* unregister */
1.367 djm 582: }
1.121 markus 583: }
584:
585: /* Free the channel and close its fd/socket. */
586: void
1.367 djm 587: channel_free(struct ssh *ssh, Channel *c)
1.121 markus 588: {
1.367 djm 589: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 590: char *s;
1.209 avsm 591: u_int i, n;
1.354 markus 592: Channel *other;
1.275 djm 593: struct channel_confirm *cc;
1.121 markus 594:
1.367 djm 595: for (n = 0, i = 0; i < sc->channels_alloc; i++) {
596: if ((other = sc->channels[i]) == NULL)
597: continue;
598: n++;
599: /* detach from mux client and prepare for closing */
600: if (c->type == SSH_CHANNEL_MUX_CLIENT &&
601: other->type == SSH_CHANNEL_MUX_PROXY &&
602: other->mux_ctx == c) {
603: other->mux_ctx = NULL;
604: other->type = SSH_CHANNEL_OPEN;
605: other->istate = CHAN_INPUT_CLOSED;
606: other->ostate = CHAN_OUTPUT_CLOSED;
1.354 markus 607: }
608: }
1.209 avsm 609: debug("channel %d: free: %s, nchannels %u", c->self,
1.121 markus 610: c->remote_name ? c->remote_name : "???", n);
611:
1.408 mbuhl 612: if (c->type == SSH_CHANNEL_MUX_CLIENT) {
1.367 djm 613: mux_remove_remote_forwardings(ssh, c);
1.408 mbuhl 614: free(c->mux_ctx);
615: c->mux_ctx = NULL;
616: } else if (c->type == SSH_CHANNEL_MUX_LISTENER) {
1.401 djm 617: free(c->mux_ctx);
618: c->mux_ctx = NULL;
619: }
1.354 markus 620:
1.384 markus 621: if (log_level_get() >= SYSLOG_LEVEL_DEBUG3) {
622: s = channel_open_message(ssh);
623: debug3("channel %d: status: %s", c->self, s);
624: free(s);
625: }
1.121 markus 626:
1.367 djm 627: channel_close_fds(ssh, c);
628: sshbuf_free(c->input);
629: sshbuf_free(c->output);
630: sshbuf_free(c->extended);
631: c->input = c->output = c->extended = NULL;
1.321 djm 632: free(c->remote_name);
633: c->remote_name = NULL;
634: free(c->path);
635: c->path = NULL;
636: free(c->listening_addr);
637: c->listening_addr = NULL;
1.275 djm 638: while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) {
639: if (cc->abandon_cb != NULL)
1.367 djm 640: cc->abandon_cb(ssh, c, cc->ctx);
1.275 djm 641: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 642: freezero(cc, sizeof(*cc));
1.275 djm 643: }
1.280 djm 644: if (c->filter_cleanup != NULL && c->filter_ctx != NULL)
1.367 djm 645: c->filter_cleanup(ssh, c->self, c->filter_ctx);
646: sc->channels[c->self] = NULL;
1.396 jsg 647: freezero(c, sizeof(*c));
1.121 markus 648: }
649:
650: void
1.367 djm 651: channel_free_all(struct ssh *ssh)
1.121 markus 652: {
1.209 avsm 653: u_int i;
1.390 dtucker 654: struct ssh_channels *sc = ssh->chanctxt;
1.121 markus 655:
1.390 dtucker 656: for (i = 0; i < sc->channels_alloc; i++)
657: if (sc->channels[i] != NULL)
658: channel_free(ssh, sc->channels[i]);
659:
660: free(sc->channels);
661: sc->channels = NULL;
662: sc->channels_alloc = 0;
663:
664: free(sc->x11_saved_display);
665: sc->x11_saved_display = NULL;
666:
667: free(sc->x11_saved_proto);
668: sc->x11_saved_proto = NULL;
669:
670: free(sc->x11_saved_data);
671: sc->x11_saved_data = NULL;
672: sc->x11_saved_data_len = 0;
673:
674: free(sc->x11_fake_data);
675: sc->x11_fake_data = NULL;
676: sc->x11_fake_data_len = 0;
1.131 markus 677: }
678:
1.121 markus 679: /*
680: * Closes the sockets/fds of all channels. This is used to close extra file
681: * descriptors after a fork.
682: */
683: void
1.367 djm 684: channel_close_all(struct ssh *ssh)
1.121 markus 685: {
1.209 avsm 686: u_int i;
1.121 markus 687:
1.367 djm 688: for (i = 0; i < ssh->chanctxt->channels_alloc; i++)
689: if (ssh->chanctxt->channels[i] != NULL)
690: channel_close_fds(ssh, ssh->chanctxt->channels[i]);
1.121 markus 691: }
692:
693: /*
1.131 markus 694: * Stop listening to channels.
695: */
696: void
1.367 djm 697: channel_stop_listening(struct ssh *ssh)
1.131 markus 698: {
1.209 avsm 699: u_int i;
1.131 markus 700: Channel *c;
701:
1.367 djm 702: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
703: c = ssh->chanctxt->channels[i];
1.131 markus 704: if (c != NULL) {
705: switch (c->type) {
706: case SSH_CHANNEL_AUTH_SOCKET:
707: case SSH_CHANNEL_PORT_LISTENER:
708: case SSH_CHANNEL_RPORT_LISTENER:
709: case SSH_CHANNEL_X11_LISTENER:
1.336 millert 710: case SSH_CHANNEL_UNIX_LISTENER:
711: case SSH_CHANNEL_RUNIX_LISTENER:
1.407 djm 712: channel_close_fd(ssh, c, &c->sock);
1.367 djm 713: channel_free(ssh, c);
1.131 markus 714: break;
715: }
716: }
717: }
718: }
719:
720: /*
1.121 markus 721: * Returns true if no channel has too much buffered data, and false if one or
722: * more channel is overfull.
723: */
724: int
1.367 djm 725: channel_not_very_much_buffered_data(struct ssh *ssh)
1.121 markus 726: {
727: u_int i;
1.367 djm 728: u_int maxsize = ssh_packet_get_maxsize(ssh);
1.121 markus 729: Channel *c;
730:
1.367 djm 731: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
732: c = ssh->chanctxt->channels[i];
733: if (c == NULL || c->type != SSH_CHANNEL_OPEN)
734: continue;
735: if (sshbuf_len(c->output) > maxsize) {
736: debug2("channel %d: big output buffer %zu > %u",
737: c->self, sshbuf_len(c->output), maxsize);
738: return 0;
1.121 markus 739: }
740: }
741: return 1;
742: }
743:
744: /* Returns true if any channel is still open. */
745: int
1.367 djm 746: channel_still_open(struct ssh *ssh)
1.121 markus 747: {
1.209 avsm 748: u_int i;
1.121 markus 749: Channel *c;
750:
1.367 djm 751: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
752: c = ssh->chanctxt->channels[i];
1.121 markus 753: if (c == NULL)
754: continue;
755: switch (c->type) {
756: case SSH_CHANNEL_X11_LISTENER:
757: case SSH_CHANNEL_PORT_LISTENER:
758: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 759: case SSH_CHANNEL_MUX_LISTENER:
1.121 markus 760: case SSH_CHANNEL_CLOSED:
761: case SSH_CHANNEL_AUTH_SOCKET:
762: case SSH_CHANNEL_DYNAMIC:
1.372 markus 763: case SSH_CHANNEL_RDYNAMIC_OPEN:
1.121 markus 764: case SSH_CHANNEL_CONNECTING:
765: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 766: case SSH_CHANNEL_ABANDONED:
1.336 millert 767: case SSH_CHANNEL_UNIX_LISTENER:
768: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 769: continue;
770: case SSH_CHANNEL_LARVAL:
771: continue;
772: case SSH_CHANNEL_OPENING:
773: case SSH_CHANNEL_OPEN:
1.372 markus 774: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 775: case SSH_CHANNEL_X11_OPEN:
1.302 djm 776: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 777: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 778: return 1;
779: default:
1.403 djm 780: fatal_f("bad channel type %d", c->type);
1.121 markus 781: /* NOTREACHED */
782: }
783: }
784: return 0;
785: }
786:
787: /* Returns the id of an open channel suitable for keepaliving */
788: int
1.367 djm 789: channel_find_open(struct ssh *ssh)
1.121 markus 790: {
1.209 avsm 791: u_int i;
1.121 markus 792: Channel *c;
793:
1.367 djm 794: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
795: c = ssh->chanctxt->channels[i];
1.368 djm 796: if (c == NULL || !c->have_remote_id)
1.121 markus 797: continue;
798: switch (c->type) {
799: case SSH_CHANNEL_CLOSED:
800: case SSH_CHANNEL_DYNAMIC:
1.372 markus 801: case SSH_CHANNEL_RDYNAMIC_OPEN:
802: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 803: case SSH_CHANNEL_X11_LISTENER:
804: case SSH_CHANNEL_PORT_LISTENER:
805: case SSH_CHANNEL_RPORT_LISTENER:
1.302 djm 806: case SSH_CHANNEL_MUX_LISTENER:
807: case SSH_CHANNEL_MUX_CLIENT:
1.354 markus 808: case SSH_CHANNEL_MUX_PROXY:
1.121 markus 809: case SSH_CHANNEL_OPENING:
810: case SSH_CHANNEL_CONNECTING:
811: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 812: case SSH_CHANNEL_ABANDONED:
1.336 millert 813: case SSH_CHANNEL_UNIX_LISTENER:
814: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 815: continue;
816: case SSH_CHANNEL_LARVAL:
817: case SSH_CHANNEL_AUTH_SOCKET:
818: case SSH_CHANNEL_OPEN:
819: case SSH_CHANNEL_X11_OPEN:
820: return i;
821: default:
1.403 djm 822: fatal_f("bad channel type %d", c->type);
1.121 markus 823: /* NOTREACHED */
824: }
825: }
826: return -1;
827: }
828:
1.385 djm 829: /* Returns the state of the channel's extended usage flag */
830: const char *
831: channel_format_extended_usage(const Channel *c)
832: {
833: if (c->efd == -1)
834: return "closed";
835:
836: switch (c->extended_usage) {
837: case CHAN_EXTENDED_WRITE:
838: return "write";
839: case CHAN_EXTENDED_READ:
840: return "read";
841: case CHAN_EXTENDED_IGNORE:
842: return "ignore";
843: default:
844: return "UNKNOWN";
845: }
846: }
847:
1.386 djm 848: static char *
849: channel_format_status(const Channel *c)
850: {
851: char *ret = NULL;
852:
853: xasprintf(&ret, "t%d %s%u i%u/%zu o%u/%zu e[%s]/%zu "
1.411 ! djm 854: "fd %d/%d/%d sock %d cc %d io 0x%02x/0x%02x",
1.386 djm 855: c->type,
856: c->have_remote_id ? "r" : "nr", c->remote_id,
857: c->istate, sshbuf_len(c->input),
858: c->ostate, sshbuf_len(c->output),
859: channel_format_extended_usage(c), sshbuf_len(c->extended),
1.411 ! djm 860: c->rfd, c->wfd, c->efd, c->sock, c->ctl_chan,
! 861: c->io_want, c->io_ready);
1.386 djm 862: return ret;
863: }
864:
1.121 markus 865: /*
866: * Returns a message describing the currently open forwarded connections,
867: * suitable for sending to the client. The message contains crlf pairs for
868: * newlines.
869: */
870: char *
1.367 djm 871: channel_open_message(struct ssh *ssh)
1.121 markus 872: {
1.367 djm 873: struct sshbuf *buf;
1.121 markus 874: Channel *c;
1.209 avsm 875: u_int i;
1.367 djm 876: int r;
1.386 djm 877: char *cp, *ret;
1.121 markus 878:
1.367 djm 879: if ((buf = sshbuf_new()) == NULL)
1.403 djm 880: fatal_f("sshbuf_new");
1.367 djm 881: if ((r = sshbuf_putf(buf,
882: "The following connections are open:\r\n")) != 0)
1.403 djm 883: fatal_fr(r, "sshbuf_putf");
1.367 djm 884: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
885: c = ssh->chanctxt->channels[i];
1.121 markus 886: if (c == NULL)
887: continue;
888: switch (c->type) {
889: case SSH_CHANNEL_X11_LISTENER:
890: case SSH_CHANNEL_PORT_LISTENER:
891: case SSH_CHANNEL_RPORT_LISTENER:
892: case SSH_CHANNEL_CLOSED:
893: case SSH_CHANNEL_AUTH_SOCKET:
894: case SSH_CHANNEL_ZOMBIE:
1.323 dtucker 895: case SSH_CHANNEL_ABANDONED:
1.302 djm 896: case SSH_CHANNEL_MUX_LISTENER:
1.336 millert 897: case SSH_CHANNEL_UNIX_LISTENER:
898: case SSH_CHANNEL_RUNIX_LISTENER:
1.121 markus 899: continue;
900: case SSH_CHANNEL_LARVAL:
901: case SSH_CHANNEL_OPENING:
902: case SSH_CHANNEL_CONNECTING:
903: case SSH_CHANNEL_DYNAMIC:
1.372 markus 904: case SSH_CHANNEL_RDYNAMIC_OPEN:
905: case SSH_CHANNEL_RDYNAMIC_FINISH:
1.121 markus 906: case SSH_CHANNEL_OPEN:
907: case SSH_CHANNEL_X11_OPEN:
1.354 markus 908: case SSH_CHANNEL_MUX_PROXY:
909: case SSH_CHANNEL_MUX_CLIENT:
1.386 djm 910: cp = channel_format_status(c);
911: if ((r = sshbuf_putf(buf, " #%d %.300s (%s)\r\n",
912: c->self, c->remote_name, cp)) != 0) {
913: free(cp);
1.403 djm 914: fatal_fr(r, "sshbuf_putf");
1.386 djm 915: }
916: free(cp);
1.121 markus 917: continue;
918: default:
1.403 djm 919: fatal_f("bad channel type %d", c->type);
1.121 markus 920: /* NOTREACHED */
921: }
922: }
1.367 djm 923: if ((ret = sshbuf_dup_string(buf)) == NULL)
1.403 djm 924: fatal_f("sshbuf_dup_string");
1.367 djm 925: sshbuf_free(buf);
926: return ret;
927: }
928:
929: static void
930: open_preamble(struct ssh *ssh, const char *where, Channel *c, const char *type)
931: {
932: int r;
933:
934: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN)) != 0 ||
935: (r = sshpkt_put_cstring(ssh, type)) != 0 ||
936: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
937: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
938: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0) {
1.403 djm 939: fatal_r(r, "%s: channel %i: open", where, c->self);
1.367 djm 940: }
1.121 markus 941: }
942:
943: void
1.367 djm 944: channel_send_open(struct ssh *ssh, int id)
1.121 markus 945: {
1.367 djm 946: Channel *c = channel_lookup(ssh, id);
947: int r;
1.180 deraadt 948:
1.121 markus 949: if (c == NULL) {
1.188 itojun 950: logit("channel_send_open: %d: bad id", id);
1.121 markus 951: return;
952: }
1.184 markus 953: debug2("channel %d: send open", id);
1.367 djm 954: open_preamble(ssh, __func__, c, c->ctype);
955: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 956: fatal_fr(r, "channel %i", c->self);
1.121 markus 957: }
958:
959: void
1.367 djm 960: channel_request_start(struct ssh *ssh, int id, char *service, int wantconfirm)
1.121 markus 961: {
1.367 djm 962: Channel *c = channel_lookup(ssh, id);
963: int r;
1.180 deraadt 964:
1.121 markus 965: if (c == NULL) {
1.403 djm 966: logit_f("%d: unknown channel id", id);
1.121 markus 967: return;
968: }
1.368 djm 969: if (!c->have_remote_id)
1.403 djm 970: fatal_f("channel %d: no remote id", c->self);
1.368 djm 971:
1.204 djm 972: debug2("channel %d: request %s confirm %d", id, service, wantconfirm);
1.367 djm 973: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_REQUEST)) != 0 ||
974: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
975: (r = sshpkt_put_cstring(ssh, service)) != 0 ||
976: (r = sshpkt_put_u8(ssh, wantconfirm)) != 0) {
1.403 djm 977: fatal_fr(r, "channel %i", c->self);
1.367 djm 978: }
1.121 markus 979: }
1.241 deraadt 980:
1.121 markus 981: void
1.367 djm 982: channel_register_status_confirm(struct ssh *ssh, int id,
983: channel_confirm_cb *cb, channel_confirm_abandon_cb *abandon_cb, void *ctx)
1.275 djm 984: {
985: struct channel_confirm *cc;
986: Channel *c;
987:
1.367 djm 988: if ((c = channel_lookup(ssh, id)) == NULL)
1.403 djm 989: fatal_f("%d: bad id", id);
1.275 djm 990:
1.327 djm 991: cc = xcalloc(1, sizeof(*cc));
1.275 djm 992: cc->cb = cb;
993: cc->abandon_cb = abandon_cb;
994: cc->ctx = ctx;
995: TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry);
996: }
997:
998: void
1.367 djm 999: channel_register_open_confirm(struct ssh *ssh, int id,
1000: channel_open_fn *fn, void *ctx)
1.121 markus 1001: {
1.367 djm 1002: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1003:
1.121 markus 1004: if (c == NULL) {
1.403 djm 1005: logit_f("%d: bad id", id);
1.121 markus 1006: return;
1007: }
1.275 djm 1008: c->open_confirm = fn;
1009: c->open_confirm_ctx = ctx;
1.121 markus 1010: }
1.241 deraadt 1011:
1.121 markus 1012: void
1.367 djm 1013: channel_register_cleanup(struct ssh *ssh, int id,
1014: channel_callback_fn *fn, int do_close)
1.121 markus 1015: {
1.367 djm 1016: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1017:
1.121 markus 1018: if (c == NULL) {
1.403 djm 1019: logit_f("%d: bad id", id);
1.121 markus 1020: return;
1021: }
1.131 markus 1022: c->detach_user = fn;
1.225 djm 1023: c->detach_close = do_close;
1.121 markus 1024: }
1.241 deraadt 1025:
1.121 markus 1026: void
1.367 djm 1027: channel_cancel_cleanup(struct ssh *ssh, int id)
1.121 markus 1028: {
1.367 djm 1029: Channel *c = channel_by_id(ssh, id);
1.180 deraadt 1030:
1.121 markus 1031: if (c == NULL) {
1.403 djm 1032: logit_f("%d: bad id", id);
1.121 markus 1033: return;
1.52 markus 1034: }
1.131 markus 1035: c->detach_user = NULL;
1.225 djm 1036: c->detach_close = 0;
1.121 markus 1037: }
1.241 deraadt 1038:
1.121 markus 1039: void
1.367 djm 1040: channel_register_filter(struct ssh *ssh, int id, channel_infilter_fn *ifn,
1.280 djm 1041: channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx)
1.121 markus 1042: {
1.367 djm 1043: Channel *c = channel_lookup(ssh, id);
1.180 deraadt 1044:
1.121 markus 1045: if (c == NULL) {
1.403 djm 1046: logit_f("%d: bad id", id);
1.121 markus 1047: return;
1.52 markus 1048: }
1.231 reyk 1049: c->input_filter = ifn;
1050: c->output_filter = ofn;
1.279 djm 1051: c->filter_ctx = ctx;
1.280 djm 1052: c->filter_cleanup = cfn;
1.52 markus 1053: }
1054:
1.49 markus 1055: void
1.367 djm 1056: channel_set_fds(struct ssh *ssh, int id, int rfd, int wfd, int efd,
1.282 dtucker 1057: int extusage, int nonblock, int is_tty, u_int window_max)
1.1 deraadt 1058: {
1.367 djm 1059: Channel *c = channel_lookup(ssh, id);
1060: int r;
1.180 deraadt 1061:
1.121 markus 1062: if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
1063: fatal("channel_activate for non-larval channel %d.", id);
1.368 djm 1064: if (!c->have_remote_id)
1.403 djm 1065: fatal_f("channel %d: no remote id", c->self);
1.368 djm 1066:
1.367 djm 1067: channel_register_fds(ssh, c, rfd, wfd, efd, extusage, nonblock, is_tty);
1.121 markus 1068: c->type = SSH_CHANNEL_OPEN;
1.168 markus 1069: c->local_window = c->local_window_max = window_max;
1.367 djm 1070:
1071: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
1072: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1073: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1074: (r = sshpkt_send(ssh)) != 0)
1.403 djm 1075: fatal_fr(r, "channel %i", c->self);
1.1 deraadt 1076: }
1077:
1.127 itojun 1078: static void
1.410 djm 1079: channel_pre_listener(struct ssh *ssh, Channel *c)
1.41 markus 1080: {
1.410 djm 1081: c->io_want = SSH_CHAN_IO_SOCK_R;
1.41 markus 1082: }
1083:
1.127 itojun 1084: static void
1.410 djm 1085: channel_pre_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1086: {
1087: debug3("channel %d: waiting for connection", c->self);
1.410 djm 1088: c->io_want = SSH_CHAN_IO_SOCK_W;
1.75 markus 1089: }
1090:
1.127 itojun 1091: static void
1.410 djm 1092: channel_pre_open(struct ssh *ssh, Channel *c)
1.41 markus 1093: {
1.410 djm 1094: c->io_want = 0;
1.44 markus 1095: if (c->istate == CHAN_INPUT_OPEN &&
1.358 djm 1096: c->remote_window > 0 &&
1.367 djm 1097: sshbuf_len(c->input) < c->remote_window &&
1098: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1099: c->io_want |= SSH_CHAN_IO_RFD;
1.44 markus 1100: if (c->ostate == CHAN_OUTPUT_OPEN ||
1101: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1102: if (sshbuf_len(c->output) > 0) {
1.410 djm 1103: c->io_want |= SSH_CHAN_IO_WFD;
1.44 markus 1104: } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.172 markus 1105: if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
1.367 djm 1106: debug2("channel %d: "
1107: "obuf_empty delayed efd %d/(%zu)", c->self,
1108: c->efd, sshbuf_len(c->extended));
1.172 markus 1109: else
1.367 djm 1110: chan_obuf_empty(ssh, c);
1.44 markus 1111: }
1112: }
1113: /** XXX check close conditions, too */
1.358 djm 1114: if (c->efd != -1 && !(c->istate == CHAN_INPUT_CLOSED &&
1115: c->ostate == CHAN_OUTPUT_CLOSED)) {
1.44 markus 1116: if (c->extended_usage == CHAN_EXTENDED_WRITE &&
1.367 djm 1117: sshbuf_len(c->extended) > 0)
1.410 djm 1118: c->io_want |= SSH_CHAN_IO_EFD_W;
1.306 djm 1119: else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) &&
1120: (c->extended_usage == CHAN_EXTENDED_READ ||
1121: c->extended_usage == CHAN_EXTENDED_IGNORE) &&
1.367 djm 1122: sshbuf_len(c->extended) < c->remote_window)
1.410 djm 1123: c->io_want |= SSH_CHAN_IO_EFD_R;
1.44 markus 1124: }
1.204 djm 1125: /* XXX: What about efd? races? */
1.44 markus 1126: }
1127:
1.41 markus 1128: /*
1129: * This is a special state for X11 authentication spoofing. An opened X11
1130: * connection (when authentication spoofing is being done) remains in this
1131: * state until the first packet has been completely read. The authentication
1132: * data in that packet is then substituted by the real data if it matches the
1133: * fake data, and the channel is put into normal mode.
1.51 markus 1134: * XXX All this happens at the client side.
1.121 markus 1135: * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
1.41 markus 1136: */
1.127 itojun 1137: static int
1.367 djm 1138: x11_open_helper(struct ssh *ssh, struct sshbuf *b)
1.1 deraadt 1139: {
1.367 djm 1140: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 1141: u_char *ucp;
1142: u_int proto_len, data_len;
1.25 markus 1143:
1.347 djm 1144: /* Is this being called after the refusal deadline? */
1.367 djm 1145: if (sc->x11_refuse_time != 0 &&
1146: (u_int)monotime() >= sc->x11_refuse_time) {
1.347 djm 1147: verbose("Rejected X11 connection after ForwardX11Timeout "
1148: "expired");
1149: return -1;
1150: }
1151:
1.41 markus 1152: /* Check if the fixed size part of the packet is in buffer. */
1.367 djm 1153: if (sshbuf_len(b) < 12)
1.41 markus 1154: return 0;
1155:
1156: /* Parse the lengths of variable-length fields. */
1.367 djm 1157: ucp = sshbuf_mutable_ptr(b);
1.41 markus 1158: if (ucp[0] == 0x42) { /* Byte order MSB first. */
1159: proto_len = 256 * ucp[6] + ucp[7];
1160: data_len = 256 * ucp[8] + ucp[9];
1161: } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
1162: proto_len = ucp[6] + 256 * ucp[7];
1163: data_len = ucp[8] + 256 * ucp[9];
1164: } else {
1.194 markus 1165: debug2("Initial X11 packet contains bad byte order byte: 0x%x",
1.148 deraadt 1166: ucp[0]);
1.41 markus 1167: return -1;
1168: }
1169:
1170: /* Check if the whole packet is in buffer. */
1.367 djm 1171: if (sshbuf_len(b) <
1.41 markus 1172: 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
1173: return 0;
1174:
1175: /* Check if authentication protocol matches. */
1.367 djm 1176: if (proto_len != strlen(sc->x11_saved_proto) ||
1177: memcmp(ucp + 12, sc->x11_saved_proto, proto_len) != 0) {
1.194 markus 1178: debug2("X11 connection uses different authentication protocol.");
1.41 markus 1179: return -1;
1180: }
1181: /* Check if authentication data matches our fake data. */
1.367 djm 1182: if (data_len != sc->x11_fake_data_len ||
1.308 djm 1183: timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1184: sc->x11_fake_data, sc->x11_fake_data_len) != 0) {
1.194 markus 1185: debug2("X11 auth data does not match fake data.");
1.41 markus 1186: return -1;
1187: }
1188: /* Check fake data length */
1.367 djm 1189: if (sc->x11_fake_data_len != sc->x11_saved_data_len) {
1.41 markus 1190: error("X11 fake_data_len %d != saved_data_len %d",
1.367 djm 1191: sc->x11_fake_data_len, sc->x11_saved_data_len);
1.41 markus 1192: return -1;
1193: }
1194: /*
1195: * Received authentication protocol and data match
1196: * our fake data. Substitute the fake data with real
1197: * data.
1198: */
1199: memcpy(ucp + 12 + ((proto_len + 3) & ~3),
1.367 djm 1200: sc->x11_saved_data, sc->x11_saved_data_len);
1.41 markus 1201: return 1;
1202: }
1203:
1.127 itojun 1204: static void
1.410 djm 1205: channel_pre_x11_open(struct ssh *ssh, Channel *c)
1.41 markus 1206: {
1.367 djm 1207: int ret = x11_open_helper(ssh, c->output);
1.133 markus 1208:
1209: /* c->force_drain = 1; */
1210:
1.41 markus 1211: if (ret == 1) {
1212: c->type = SSH_CHANNEL_OPEN;
1.410 djm 1213: channel_pre_open(ssh, c);
1.41 markus 1214: } else if (ret == -1) {
1.188 itojun 1215: logit("X11 connection rejected because of wrong authentication.");
1.367 djm 1216: debug2("X11 rejected %d i%d/o%d",
1217: c->self, c->istate, c->ostate);
1218: chan_read_failed(ssh, c);
1219: sshbuf_reset(c->input);
1220: chan_ibuf_empty(ssh, c);
1221: sshbuf_reset(c->output);
1222: chan_write_failed(ssh, c);
1.194 markus 1223: debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
1.41 markus 1224: }
1225: }
1.25 markus 1226:
1.302 djm 1227: static void
1.410 djm 1228: channel_pre_mux_client(struct ssh *ssh, Channel *c)
1.302 djm 1229: {
1.410 djm 1230: c->io_want = 0;
1.304 djm 1231: if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause &&
1.367 djm 1232: sshbuf_check_reserve(c->input, CHAN_RBUF) == 0)
1.410 djm 1233: c->io_want |= SSH_CHAN_IO_RFD;
1.302 djm 1234: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1235: /* clear buffer immediately (discard any partial packet) */
1.367 djm 1236: sshbuf_reset(c->input);
1237: chan_ibuf_empty(ssh, c);
1.302 djm 1238: /* Start output drain. XXX just kill chan? */
1.367 djm 1239: chan_rcvd_oclose(ssh, c);
1.302 djm 1240: }
1241: if (c->ostate == CHAN_OUTPUT_OPEN ||
1242: c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
1.367 djm 1243: if (sshbuf_len(c->output) > 0)
1.410 djm 1244: c->io_want |= SSH_CHAN_IO_WFD;
1.302 djm 1245: else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN)
1.367 djm 1246: chan_obuf_empty(ssh, c);
1.302 djm 1247: }
1248: }
1249:
1.104 markus 1250: /* try to decode a socks4 header */
1.127 itojun 1251: static int
1.372 markus 1252: channel_decode_socks4(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.103 markus 1253: {
1.367 djm 1254: const u_char *p;
1255: char *host;
1.292 djm 1256: u_int len, have, i, found, need;
1.148 deraadt 1257: char username[256];
1.103 markus 1258: struct {
1259: u_int8_t version;
1260: u_int8_t command;
1261: u_int16_t dest_port;
1.104 markus 1262: struct in_addr dest_addr;
1.103 markus 1263: } s4_req, s4_rsp;
1.367 djm 1264: int r;
1.103 markus 1265:
1.104 markus 1266: debug2("channel %d: decode socks4", c->self);
1.109 markus 1267:
1.372 markus 1268: have = sshbuf_len(input);
1.109 markus 1269: len = sizeof(s4_req);
1270: if (have < len)
1271: return 0;
1.372 markus 1272: p = sshbuf_ptr(input);
1.292 djm 1273:
1274: need = 1;
1275: /* SOCKS4A uses an invalid IP address 0.0.0.x */
1276: if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) {
1277: debug2("channel %d: socks4a request", c->self);
1278: /* ... and needs an extra string (the hostname) */
1279: need = 2;
1280: }
1281: /* Check for terminating NUL on the string(s) */
1.109 markus 1282: for (found = 0, i = len; i < have; i++) {
1283: if (p[i] == '\0') {
1.292 djm 1284: found++;
1285: if (found == need)
1286: break;
1.109 markus 1287: }
1288: if (i > 1024) {
1289: /* the peer is probably sending garbage */
1290: debug("channel %d: decode socks4: too long",
1291: c->self);
1292: return -1;
1293: }
1294: }
1.292 djm 1295: if (found < need)
1.109 markus 1296: return 0;
1.372 markus 1297: if ((r = sshbuf_get(input, &s4_req.version, 1)) != 0 ||
1298: (r = sshbuf_get(input, &s4_req.command, 1)) != 0 ||
1299: (r = sshbuf_get(input, &s4_req.dest_port, 2)) != 0 ||
1300: (r = sshbuf_get(input, &s4_req.dest_addr, 4)) != 0) {
1.403 djm 1301: debug_r(r, "channels %d: decode socks4", c->self);
1.367 djm 1302: return -1;
1303: }
1.372 markus 1304: have = sshbuf_len(input);
1305: p = sshbuf_ptr(input);
1.364 djm 1306: if (memchr(p, '\0', have) == NULL) {
1.403 djm 1307: error("channel %d: decode socks4: unterminated user", c->self);
1.364 djm 1308: return -1;
1309: }
1.103 markus 1310: len = strlen(p);
1.106 markus 1311: debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
1.367 djm 1312: len++; /* trailing '\0' */
1.103 markus 1313: strlcpy(username, p, sizeof(username));
1.403 djm 1314: if ((r = sshbuf_consume(input, len)) != 0)
1315: fatal_fr(r, "channel %d: consume", c->self);
1.321 djm 1316: free(c->path);
1317: c->path = NULL;
1.292 djm 1318: if (need == 1) { /* SOCKS4: one string */
1319: host = inet_ntoa(s4_req.dest_addr);
1.293 djm 1320: c->path = xstrdup(host);
1.292 djm 1321: } else { /* SOCKS4A: two strings */
1.372 markus 1322: have = sshbuf_len(input);
1323: p = sshbuf_ptr(input);
1.364 djm 1324: if (memchr(p, '\0', have) == NULL) {
1325: error("channel %d: decode socks4a: host not nul "
1326: "terminated", c->self);
1327: return -1;
1328: }
1.292 djm 1329: len = strlen(p);
1330: debug2("channel %d: decode socks4a: host %s/%d",
1331: c->self, p, len);
1332: len++; /* trailing '\0' */
1.293 djm 1333: if (len > NI_MAXHOST) {
1.292 djm 1334: error("channel %d: hostname \"%.100s\" too long",
1335: c->self, p);
1336: return -1;
1337: }
1.293 djm 1338: c->path = xstrdup(p);
1.403 djm 1339: if ((r = sshbuf_consume(input, len)) != 0)
1340: fatal_fr(r, "channel %d: consume", c->self);
1.292 djm 1341: }
1.103 markus 1342: c->host_port = ntohs(s4_req.dest_port);
1.148 deraadt 1343:
1.194 markus 1344: debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1.292 djm 1345: c->self, c->path, c->host_port, s4_req.command);
1.103 markus 1346:
1.104 markus 1347: if (s4_req.command != 1) {
1.292 djm 1348: debug("channel %d: cannot handle: %s cn %d",
1349: c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command);
1.104 markus 1350: return -1;
1.103 markus 1351: }
1.104 markus 1352: s4_rsp.version = 0; /* vn: 0 for reply */
1353: s4_rsp.command = 90; /* cd: req granted */
1.103 markus 1354: s4_rsp.dest_port = 0; /* ignored */
1.104 markus 1355: s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
1.403 djm 1356: if ((r = sshbuf_put(output, &s4_rsp, sizeof(s4_rsp))) != 0)
1357: fatal_fr(r, "channel %d: append reply", c->self);
1.104 markus 1358: return 1;
1359: }
1360:
1.193 markus 1361: /* try to decode a socks5 header */
1362: #define SSH_SOCKS5_AUTHDONE 0x1000
1363: #define SSH_SOCKS5_NOAUTH 0x00
1364: #define SSH_SOCKS5_IPV4 0x01
1365: #define SSH_SOCKS5_DOMAIN 0x03
1366: #define SSH_SOCKS5_IPV6 0x04
1367: #define SSH_SOCKS5_CONNECT 0x01
1368: #define SSH_SOCKS5_SUCCESS 0x00
1369:
1370: static int
1.372 markus 1371: channel_decode_socks5(Channel *c, struct sshbuf *input, struct sshbuf *output)
1.193 markus 1372: {
1.367 djm 1373: /* XXX use get/put_u8 instead of trusting struct padding */
1.193 markus 1374: struct {
1375: u_int8_t version;
1376: u_int8_t command;
1377: u_int8_t reserved;
1378: u_int8_t atyp;
1379: } s5_req, s5_rsp;
1380: u_int16_t dest_port;
1.324 djm 1381: char dest_addr[255+1], ntop[INET6_ADDRSTRLEN];
1.367 djm 1382: const u_char *p;
1.252 djm 1383: u_int have, need, i, found, nmethods, addrlen, af;
1.367 djm 1384: int r;
1.193 markus 1385:
1386: debug2("channel %d: decode socks5", c->self);
1.372 markus 1387: p = sshbuf_ptr(input);
1.193 markus 1388: if (p[0] != 0x05)
1389: return -1;
1.372 markus 1390: have = sshbuf_len(input);
1.193 markus 1391: if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
1392: /* format: ver | nmethods | methods */
1.198 djm 1393: if (have < 2)
1.193 markus 1394: return 0;
1395: nmethods = p[1];
1396: if (have < nmethods + 2)
1397: return 0;
1398: /* look for method: "NO AUTHENTICATION REQUIRED" */
1.268 stevesk 1399: for (found = 0, i = 2; i < nmethods + 2; i++) {
1.264 stevesk 1400: if (p[i] == SSH_SOCKS5_NOAUTH) {
1.193 markus 1401: found = 1;
1402: break;
1403: }
1404: }
1405: if (!found) {
1406: debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1407: c->self);
1408: return -1;
1409: }
1.403 djm 1410: if ((r = sshbuf_consume(input, nmethods + 2)) != 0)
1411: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1412: /* version, method */
1.372 markus 1413: if ((r = sshbuf_put_u8(output, 0x05)) != 0 ||
1.403 djm 1414: (r = sshbuf_put_u8(output, SSH_SOCKS5_NOAUTH)) != 0)
1415: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1416: c->flags |= SSH_SOCKS5_AUTHDONE;
1417: debug2("channel %d: socks5 auth done", c->self);
1418: return 0; /* need more */
1419: }
1420: debug2("channel %d: socks5 post auth", c->self);
1421: if (have < sizeof(s5_req)+1)
1422: return 0; /* need more */
1.247 deraadt 1423: memcpy(&s5_req, p, sizeof(s5_req));
1.193 markus 1424: if (s5_req.version != 0x05 ||
1425: s5_req.command != SSH_SOCKS5_CONNECT ||
1426: s5_req.reserved != 0x00) {
1.194 markus 1427: debug2("channel %d: only socks5 connect supported", c->self);
1.193 markus 1428: return -1;
1429: }
1.213 deraadt 1430: switch (s5_req.atyp){
1.193 markus 1431: case SSH_SOCKS5_IPV4:
1432: addrlen = 4;
1433: af = AF_INET;
1434: break;
1435: case SSH_SOCKS5_DOMAIN:
1436: addrlen = p[sizeof(s5_req)];
1437: af = -1;
1438: break;
1439: case SSH_SOCKS5_IPV6:
1440: addrlen = 16;
1441: af = AF_INET6;
1442: break;
1443: default:
1.194 markus 1444: debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp);
1.193 markus 1445: return -1;
1446: }
1.252 djm 1447: need = sizeof(s5_req) + addrlen + 2;
1448: if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
1449: need++;
1450: if (have < need)
1.193 markus 1451: return 0;
1.403 djm 1452: if ((r = sshbuf_consume(input, sizeof(s5_req))) != 0)
1453: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1454: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1455: /* host string length */
1.403 djm 1456: if ((r = sshbuf_consume(input, 1)) != 0)
1457: fatal_fr(r, "channel %d: consume", c->self);
1.367 djm 1458: }
1.372 markus 1459: if ((r = sshbuf_get(input, &dest_addr, addrlen)) != 0 ||
1460: (r = sshbuf_get(input, &dest_port, 2)) != 0) {
1.403 djm 1461: debug_r(r, "channel %d: parse addr/port", c->self);
1.367 djm 1462: return -1;
1463: }
1.193 markus 1464: dest_addr[addrlen] = '\0';
1.321 djm 1465: free(c->path);
1466: c->path = NULL;
1.293 djm 1467: if (s5_req.atyp == SSH_SOCKS5_DOMAIN) {
1.294 djm 1468: if (addrlen >= NI_MAXHOST) {
1.293 djm 1469: error("channel %d: dynamic request: socks5 hostname "
1470: "\"%.100s\" too long", c->self, dest_addr);
1471: return -1;
1472: }
1473: c->path = xstrdup(dest_addr);
1474: } else {
1475: if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL)
1476: return -1;
1477: c->path = xstrdup(ntop);
1478: }
1.193 markus 1479: c->host_port = ntohs(dest_port);
1.198 djm 1480:
1.194 markus 1481: debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1.193 markus 1482: c->self, c->path, c->host_port, s5_req.command);
1483:
1484: s5_rsp.version = 0x05;
1485: s5_rsp.command = SSH_SOCKS5_SUCCESS;
1486: s5_rsp.reserved = 0; /* ignored */
1487: s5_rsp.atyp = SSH_SOCKS5_IPV4;
1488: dest_port = 0; /* ignored */
1489:
1.372 markus 1490: if ((r = sshbuf_put(output, &s5_rsp, sizeof(s5_rsp))) != 0 ||
1491: (r = sshbuf_put_u32(output, ntohl(INADDR_ANY))) != 0 ||
1492: (r = sshbuf_put(output, &dest_port, sizeof(dest_port))) != 0)
1.403 djm 1493: fatal_fr(r, "channel %d: append reply", c->self);
1.193 markus 1494: return 1;
1.301 dtucker 1495: }
1496:
1497: Channel *
1.367 djm 1498: channel_connect_stdio_fwd(struct ssh *ssh,
1.407 djm 1499: const char *host_to_connect, u_short port_to_connect,
1500: int in, int out, int nonblock)
1.301 dtucker 1501: {
1502: Channel *c;
1503:
1.403 djm 1504: debug_f("%s:%d", host_to_connect, port_to_connect);
1.301 dtucker 1505:
1.367 djm 1506: c = channel_new(ssh, "stdio-forward", SSH_CHANNEL_OPENING, in, out,
1.301 dtucker 1507: -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.407 djm 1508: 0, "stdio-forward", nonblock);
1.301 dtucker 1509:
1510: c->path = xstrdup(host_to_connect);
1511: c->host_port = port_to_connect;
1512: c->listening_port = 0;
1513: c->force_drain = 1;
1514:
1.367 djm 1515: channel_register_fds(ssh, c, in, out, -1, 0, 1, 0);
1516: port_open_helper(ssh, c, "direct-tcpip");
1.301 dtucker 1517:
1518: return c;
1.193 markus 1519: }
1520:
1.104 markus 1521: /* dynamic port forwarding */
1.127 itojun 1522: static void
1.410 djm 1523: channel_pre_dynamic(struct ssh *ssh, Channel *c)
1.104 markus 1524: {
1.367 djm 1525: const u_char *p;
1.217 djm 1526: u_int have;
1527: int ret;
1.103 markus 1528:
1.410 djm 1529: c->io_want = 0;
1.367 djm 1530: have = sshbuf_len(c->input);
1.104 markus 1531: debug2("channel %d: pre_dynamic: have %d", c->self, have);
1.367 djm 1532: /* sshbuf_dump(c->input, stderr); */
1.104 markus 1533: /* check if the fixed size part of the packet is in buffer. */
1.193 markus 1534: if (have < 3) {
1.104 markus 1535: /* need more */
1.410 djm 1536: c->io_want |= SSH_CHAN_IO_RFD;
1.104 markus 1537: return;
1538: }
1539: /* try to guess the protocol */
1.367 djm 1540: p = sshbuf_ptr(c->input);
1541: /* XXX sshbuf_peek_u8? */
1.104 markus 1542: switch (p[0]) {
1543: case 0x04:
1.372 markus 1544: ret = channel_decode_socks4(c, c->input, c->output);
1.193 markus 1545: break;
1546: case 0x05:
1.372 markus 1547: ret = channel_decode_socks5(c, c->input, c->output);
1.104 markus 1548: break;
1549: default:
1550: ret = -1;
1551: break;
1552: }
1553: if (ret < 0) {
1.367 djm 1554: chan_mark_dead(ssh, c);
1.104 markus 1555: } else if (ret == 0) {
1556: debug2("channel %d: pre_dynamic: need more", c->self);
1557: /* need more */
1.410 djm 1558: c->io_want |= SSH_CHAN_IO_RFD;
1.372 markus 1559: if (sshbuf_len(c->output))
1.410 djm 1560: c->io_want |= SSH_CHAN_IO_WFD;
1.104 markus 1561: } else {
1562: /* switch to the next state */
1563: c->type = SSH_CHANNEL_OPENING;
1.367 djm 1564: port_open_helper(ssh, c, "direct-tcpip");
1.104 markus 1565: }
1.103 markus 1566: }
1567:
1.372 markus 1568: /* simulate read-error */
1569: static void
1570: rdynamic_close(struct ssh *ssh, Channel *c)
1571: {
1572: c->type = SSH_CHANNEL_OPEN;
1573: chan_read_failed(ssh, c);
1574: sshbuf_reset(c->input);
1575: chan_ibuf_empty(ssh, c);
1576: sshbuf_reset(c->output);
1577: chan_write_failed(ssh, c);
1578: }
1579:
1580: /* reverse dynamic port forwarding */
1581: static void
1.411 ! djm 1582: channel_before_prepare_io_rdynamic(struct ssh *ssh, Channel *c)
1.372 markus 1583: {
1584: const u_char *p;
1585: u_int have, len;
1586: int r, ret;
1587:
1588: have = sshbuf_len(c->output);
1589: debug2("channel %d: pre_rdynamic: have %d", c->self, have);
1590: /* sshbuf_dump(c->output, stderr); */
1591: /* EOF received */
1592: if (c->flags & CHAN_EOF_RCVD) {
1.403 djm 1593: if ((r = sshbuf_consume(c->output, have)) != 0)
1594: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1595: rdynamic_close(ssh, c);
1596: return;
1597: }
1598: /* check if the fixed size part of the packet is in buffer. */
1599: if (have < 3)
1600: return;
1601: /* try to guess the protocol */
1602: p = sshbuf_ptr(c->output);
1603: switch (p[0]) {
1604: case 0x04:
1605: /* switch input/output for reverse forwarding */
1606: ret = channel_decode_socks4(c, c->output, c->input);
1607: break;
1608: case 0x05:
1609: ret = channel_decode_socks5(c, c->output, c->input);
1610: break;
1611: default:
1612: ret = -1;
1613: break;
1614: }
1615: if (ret < 0) {
1616: rdynamic_close(ssh, c);
1617: } else if (ret == 0) {
1618: debug2("channel %d: pre_rdynamic: need more", c->self);
1619: /* send socks request to peer */
1620: len = sshbuf_len(c->input);
1621: if (len > 0 && len < c->remote_window) {
1622: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
1623: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1624: (r = sshpkt_put_stringb(ssh, c->input)) != 0 ||
1625: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 1626: fatal_fr(r, "channel %i: rdynamic", c->self);
1.372 markus 1627: }
1.403 djm 1628: if ((r = sshbuf_consume(c->input, len)) != 0)
1629: fatal_fr(r, "channel %d: consume", c->self);
1.372 markus 1630: c->remote_window -= len;
1631: }
1632: } else if (rdynamic_connect_finish(ssh, c) < 0) {
1633: /* the connect failed */
1634: rdynamic_close(ssh, c);
1635: }
1636: }
1637:
1.41 markus 1638: /* This is our fake X11 server socket. */
1.127 itojun 1639: static void
1.410 djm 1640: channel_post_x11_listener(struct ssh *ssh, Channel *c)
1.41 markus 1641: {
1.113 markus 1642: Channel *nc;
1.285 djm 1643: struct sockaddr_storage addr;
1.367 djm 1644: int r, newsock, oerrno, remote_port;
1.41 markus 1645: socklen_t addrlen;
1.85 markus 1646: char buf[16384], *remote_ipaddr;
1.25 markus 1647:
1.410 djm 1648: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1649: return;
1650:
1651: debug("X11 connection requested.");
1652: addrlen = sizeof(addr);
1653: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1654: if (c->single_connection) {
1655: oerrno = errno;
1656: debug2("single_connection: closing X11 listener.");
1.407 djm 1657: channel_close_fd(ssh, c, &c->sock);
1.367 djm 1658: chan_mark_dead(ssh, c);
1659: errno = oerrno;
1660: }
1.393 deraadt 1661: if (newsock == -1) {
1.367 djm 1662: if (errno != EINTR && errno != EWOULDBLOCK &&
1663: errno != ECONNABORTED)
1664: error("accept: %.100s", strerror(errno));
1665: if (errno == EMFILE || errno == ENFILE)
1666: c->notbefore = monotime() + 1;
1667: return;
1668: }
1669: set_nodelay(newsock);
1670: remote_ipaddr = get_peer_ipaddr(newsock);
1671: remote_port = get_peer_port(newsock);
1672: snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
1673: remote_ipaddr, remote_port);
1674:
1675: nc = channel_new(ssh, "accepted x11 socket",
1676: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1677: c->local_window_max, c->local_maxpacket, 0, buf, 1);
1678: open_preamble(ssh, __func__, nc, "x11");
1.378 djm 1679: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1680: (r = sshpkt_put_u32(ssh, remote_port)) != 0) {
1.403 djm 1681: fatal_fr(r, "channel %i: reply", c->self);
1.41 markus 1682: }
1.367 djm 1683: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1684: fatal_fr(r, "channel %i: send", c->self);
1.367 djm 1685: free(remote_ipaddr);
1.41 markus 1686: }
1.25 markus 1687:
1.127 itojun 1688: static void
1.367 djm 1689: port_open_helper(struct ssh *ssh, Channel *c, char *rtype)
1.103 markus 1690: {
1.328 djm 1691: char *local_ipaddr = get_local_ipaddr(c->sock);
1.350 djm 1692: int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock);
1.103 markus 1693: char *remote_ipaddr = get_peer_ipaddr(c->sock);
1.216 markus 1694: int remote_port = get_peer_port(c->sock);
1.367 djm 1695: int r;
1.303 djm 1696:
1697: if (remote_port == -1) {
1698: /* Fake addr/port to appease peers that validate it (Tectia) */
1.321 djm 1699: free(remote_ipaddr);
1.303 djm 1700: remote_ipaddr = xstrdup("127.0.0.1");
1701: remote_port = 65535;
1702: }
1.103 markus 1703:
1.367 djm 1704: free(c->remote_name);
1705: xasprintf(&c->remote_name,
1.103 markus 1706: "%s: listening port %d for %.100s port %d, "
1.328 djm 1707: "connect from %.200s port %d to %.100s port %d",
1.103 markus 1708: rtype, c->listening_port, c->path, c->host_port,
1.328 djm 1709: remote_ipaddr, remote_port, local_ipaddr, local_port);
1.103 markus 1710:
1.367 djm 1711: open_preamble(ssh, __func__, c, rtype);
1.358 djm 1712: if (strcmp(rtype, "direct-tcpip") == 0) {
1713: /* target host, port */
1.367 djm 1714: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1715: (r = sshpkt_put_u32(ssh, c->host_port)) != 0)
1716: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1717: } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) {
1718: /* target path */
1.403 djm 1719: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1720: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1721: } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1722: /* listen path */
1.403 djm 1723: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0)
1724: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1725: } else {
1.358 djm 1726: /* listen address, port */
1.367 djm 1727: if ((r = sshpkt_put_cstring(ssh, c->path)) != 0 ||
1.403 djm 1728: (r = sshpkt_put_u32(ssh, local_port)) != 0)
1729: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1730: }
1731: if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) {
1732: /* reserved for future owner/mode info */
1.403 djm 1733: if ((r = sshpkt_put_cstring(ssh, "")) != 0)
1734: fatal_fr(r, "channel %i: reply", c->self);
1.358 djm 1735: } else {
1736: /* originator host and port */
1.367 djm 1737: if ((r = sshpkt_put_cstring(ssh, remote_ipaddr)) != 0 ||
1.403 djm 1738: (r = sshpkt_put_u32(ssh, (u_int)remote_port)) != 0)
1739: fatal_fr(r, "channel %i: reply", c->self);
1.103 markus 1740: }
1.367 djm 1741: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1742: fatal_fr(r, "channel %i: send", c->self);
1.321 djm 1743: free(remote_ipaddr);
1.328 djm 1744: free(local_ipaddr);
1.103 markus 1745: }
1746:
1.347 djm 1747: void
1.367 djm 1748: channel_set_x11_refuse_time(struct ssh *ssh, u_int refuse_time)
1.347 djm 1749: {
1.367 djm 1750: ssh->chanctxt->x11_refuse_time = refuse_time;
1.226 djm 1751: }
1752:
1.41 markus 1753: /*
1754: * This socket is listening for connections to a forwarded TCP/IP port.
1755: */
1.127 itojun 1756: static void
1.410 djm 1757: channel_post_port_listener(struct ssh *ssh, Channel *c)
1.41 markus 1758: {
1.103 markus 1759: Channel *nc;
1.285 djm 1760: struct sockaddr_storage addr;
1.113 markus 1761: int newsock, nextstate;
1.41 markus 1762: socklen_t addrlen;
1.103 markus 1763: char *rtype;
1.73 markus 1764:
1.410 djm 1765: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1766: return;
1767:
1768: debug("Connection to port %d forwarding to %.100s port %d requested.",
1769: c->listening_port, c->path, c->host_port);
1.103 markus 1770:
1.367 djm 1771: if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
1772: nextstate = SSH_CHANNEL_OPENING;
1773: rtype = "forwarded-tcpip";
1774: } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) {
1775: nextstate = SSH_CHANNEL_OPENING;
1776: rtype = "forwarded-streamlocal@openssh.com";
1777: } else if (c->host_port == PORT_STREAMLOCAL) {
1778: nextstate = SSH_CHANNEL_OPENING;
1779: rtype = "direct-streamlocal@openssh.com";
1780: } else if (c->host_port == 0) {
1781: nextstate = SSH_CHANNEL_DYNAMIC;
1782: rtype = "dynamic-tcpip";
1783: } else {
1784: nextstate = SSH_CHANNEL_OPENING;
1785: rtype = "direct-tcpip";
1786: }
1.103 markus 1787:
1.367 djm 1788: addrlen = sizeof(addr);
1789: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1790: if (newsock == -1) {
1.367 djm 1791: if (errno != EINTR && errno != EWOULDBLOCK &&
1792: errno != ECONNABORTED)
1793: error("accept: %.100s", strerror(errno));
1794: if (errno == EMFILE || errno == ENFILE)
1795: c->notbefore = monotime() + 1;
1796: return;
1.41 markus 1797: }
1.367 djm 1798: if (c->host_port != PORT_STREAMLOCAL)
1799: set_nodelay(newsock);
1800: nc = channel_new(ssh, rtype, nextstate, newsock, newsock, -1,
1801: c->local_window_max, c->local_maxpacket, 0, rtype, 1);
1802: nc->listening_port = c->listening_port;
1803: nc->host_port = c->host_port;
1804: if (c->path != NULL)
1805: nc->path = xstrdup(c->path);
1806:
1807: if (nextstate != SSH_CHANNEL_DYNAMIC)
1808: port_open_helper(ssh, nc, rtype);
1.41 markus 1809: }
1.25 markus 1810:
1.41 markus 1811: /*
1812: * This is the authentication agent socket listening for connections from
1813: * clients.
1814: */
1.127 itojun 1815: static void
1.410 djm 1816: channel_post_auth_listener(struct ssh *ssh, Channel *c)
1.41 markus 1817: {
1.113 markus 1818: Channel *nc;
1.367 djm 1819: int r, newsock;
1.285 djm 1820: struct sockaddr_storage addr;
1.41 markus 1821: socklen_t addrlen;
1.25 markus 1822:
1.410 djm 1823: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.367 djm 1824: return;
1825:
1826: addrlen = sizeof(addr);
1827: newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen);
1.393 deraadt 1828: if (newsock == -1) {
1.367 djm 1829: error("accept from auth socket: %.100s", strerror(errno));
1830: if (errno == EMFILE || errno == ENFILE)
1831: c->notbefore = monotime() + 1;
1832: return;
1.41 markus 1833: }
1.367 djm 1834: nc = channel_new(ssh, "accepted auth socket",
1835: SSH_CHANNEL_OPENING, newsock, newsock, -1,
1836: c->local_window_max, c->local_maxpacket,
1837: 0, "accepted auth socket", 1);
1838: open_preamble(ssh, __func__, nc, "auth-agent@openssh.com");
1839: if ((r = sshpkt_send(ssh)) != 0)
1.403 djm 1840: fatal_fr(r, "channel %i", c->self);
1.41 markus 1841: }
1.25 markus 1842:
1.127 itojun 1843: static void
1.410 djm 1844: channel_post_connecting(struct ssh *ssh, Channel *c)
1.75 markus 1845: {
1.372 markus 1846: int err = 0, sock, isopen, r;
1.129 stevesk 1847: socklen_t sz = sizeof(err);
1.114 markus 1848:
1.410 djm 1849: if ((c->io_ready & SSH_CHAN_IO_SOCK_W) == 0)
1.367 djm 1850: return;
1.368 djm 1851: if (!c->have_remote_id)
1.403 djm 1852: fatal_f("channel %d: no remote id", c->self);
1.372 markus 1853: /* for rdynamic the OPEN_CONFIRMATION has been sent already */
1854: isopen = (c->type == SSH_CHANNEL_RDYNAMIC_FINISH);
1.393 deraadt 1855: if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) == -1) {
1.367 djm 1856: err = errno;
1857: error("getsockopt SO_ERROR failed");
1858: }
1859: if (err == 0) {
1860: debug("channel %d: connected to %s port %d",
1861: c->self, c->connect_ctx.host, c->connect_ctx.port);
1862: channel_connect_ctx_free(&c->connect_ctx);
1863: c->type = SSH_CHANNEL_OPEN;
1.372 markus 1864: if (isopen) {
1865: /* no message necessary */
1866: } else {
1867: if ((r = sshpkt_start(ssh,
1868: SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
1869: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1870: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
1871: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 1872: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0 ||
1873: (r = sshpkt_send(ssh)) != 0)
1874: fatal_fr(r, "channel %i open confirm", c->self);
1.367 djm 1875: }
1876: } else {
1877: debug("channel %d: connection failed: %s",
1878: c->self, strerror(err));
1879: /* Try next address, if any */
1880: if ((sock = connect_next(&c->connect_ctx)) > 0) {
1881: close(c->sock);
1882: c->sock = c->rfd = c->wfd = sock;
1883: return;
1884: }
1885: /* Exhausted all addresses */
1886: error("connect_to %.100s port %d: failed.",
1887: c->connect_ctx.host, c->connect_ctx.port);
1888: channel_connect_ctx_free(&c->connect_ctx);
1.372 markus 1889: if (isopen) {
1890: rdynamic_close(ssh, c);
1891: } else {
1892: if ((r = sshpkt_start(ssh,
1893: SSH2_MSG_CHANNEL_OPEN_FAILURE)) != 0 ||
1894: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.378 djm 1895: (r = sshpkt_put_u32(ssh,
1896: SSH2_OPEN_CONNECT_FAILED)) != 0 ||
1897: (r = sshpkt_put_cstring(ssh, strerror(err))) != 0 ||
1.403 djm 1898: (r = sshpkt_put_cstring(ssh, "")) != 0 ||
1899: (r = sshpkt_send(ssh)) != 0)
1900: fatal_fr(r, "channel %i: failure", c->self);
1.372 markus 1901: chan_mark_dead(ssh, c);
1.75 markus 1902: }
1903: }
1904: }
1905:
1.127 itojun 1906: static int
1.410 djm 1907: channel_handle_rfd(struct ssh *ssh, Channel *c)
1.41 markus 1908: {
1.214 markus 1909: char buf[CHAN_RBUF];
1.367 djm 1910: ssize_t len;
1911: int r;
1.25 markus 1912:
1.410 djm 1913: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 1914: return 1;
1915:
1916: len = read(c->rfd, buf, sizeof(buf));
1.393 deraadt 1917: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1918: return 1;
1919: if (len <= 0) {
1920: debug2("channel %d: read<=0 rfd %d len %zd",
1921: c->self, c->rfd, len);
1922: if (c->type != SSH_CHANNEL_OPEN) {
1923: debug2("channel %d: not open", c->self);
1924: chan_mark_dead(ssh, c);
1.41 markus 1925: return -1;
1.65 markus 1926: } else {
1.367 djm 1927: chan_read_failed(ssh, c);
1.65 markus 1928: }
1.367 djm 1929: return -1;
1930: }
1931: if (c->input_filter != NULL) {
1932: if (c->input_filter(ssh, c, buf, len) == -1) {
1933: debug2("channel %d: filter stops", c->self);
1934: chan_read_failed(ssh, c);
1935: }
1936: } else if (c->datagram) {
1937: if ((r = sshbuf_put_string(c->input, buf, len)) != 0)
1.403 djm 1938: fatal_fr(r, "channel %i: put datagram", c->self);
1939: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
1940: fatal_fr(r, "channel %i: put data", c->self);
1.41 markus 1941: return 1;
1942: }
1.241 deraadt 1943:
1.127 itojun 1944: static int
1.410 djm 1945: channel_handle_wfd(struct ssh *ssh, Channel *c)
1.41 markus 1946: {
1.95 markus 1947: struct termios tio;
1.367 djm 1948: u_char *data = NULL, *buf; /* XXX const; need filter API change */
1949: size_t dlen, olen = 0;
1950: int r, len;
1951:
1.410 djm 1952: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
1953: return 1;
1954: if (sshbuf_len(c->output) == 0)
1.367 djm 1955: return 1;
1.25 markus 1956:
1.41 markus 1957: /* Send buffered output data to the socket. */
1.367 djm 1958: olen = sshbuf_len(c->output);
1959: if (c->output_filter != NULL) {
1960: if ((buf = c->output_filter(ssh, c, &data, &dlen)) == NULL) {
1961: debug2("channel %d: filter stops", c->self);
1962: if (c->type != SSH_CHANNEL_OPEN)
1963: chan_mark_dead(ssh, c);
1964: else
1965: chan_write_failed(ssh, c);
1966: return -1;
1.231 reyk 1967: }
1.367 djm 1968: } else if (c->datagram) {
1969: if ((r = sshbuf_get_string(c->output, &data, &dlen)) != 0)
1.403 djm 1970: fatal_fr(r, "channel %i: get datagram", c->self);
1.369 djm 1971: buf = data;
1.367 djm 1972: } else {
1973: buf = data = sshbuf_mutable_ptr(c->output);
1974: dlen = sshbuf_len(c->output);
1975: }
1.231 reyk 1976:
1.367 djm 1977: if (c->datagram) {
1978: /* ignore truncated writes, datagrams might get lost */
1.374 djm 1979: len = write(c->wfd, buf, dlen);
1.367 djm 1980: free(data);
1.393 deraadt 1981: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.53 markus 1982: return 1;
1.367 djm 1983: if (len <= 0)
1984: goto write_fail;
1985: goto out;
1986: }
1987:
1988: len = write(c->wfd, buf, dlen);
1.393 deraadt 1989: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 1990: return 1;
1991: if (len <= 0) {
1992: write_fail:
1993: if (c->type != SSH_CHANNEL_OPEN) {
1994: debug2("channel %d: not open", c->self);
1995: chan_mark_dead(ssh, c);
1.41 markus 1996: return -1;
1.367 djm 1997: } else {
1998: chan_write_failed(ssh, c);
1.91 markus 1999: }
1.367 djm 2000: return -1;
2001: }
2002: if (c->isatty && dlen >= 1 && buf[0] != '\r') {
2003: if (tcgetattr(c->wfd, &tio) == 0 &&
2004: !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
2005: /*
2006: * Simulate echo to reduce the impact of
2007: * traffic analysis. We need to match the
2008: * size of a SSH2_MSG_CHANNEL_DATA message
2009: * (4 byte channel id + buf)
2010: */
2011: if ((r = sshpkt_msg_ignore(ssh, 4+len)) != 0 ||
2012: (r = sshpkt_send(ssh)) != 0)
1.403 djm 2013: fatal_fr(r, "channel %i: ignore", c->self);
1.25 markus 2014: }
1.367 djm 2015: }
1.403 djm 2016: if ((r = sshbuf_consume(c->output, len)) != 0)
2017: fatal_fr(r, "channel %i: consume", c->self);
1.309 djm 2018: out:
1.367 djm 2019: c->local_consumed += olen - sshbuf_len(c->output);
2020:
2021: return 1;
2022: }
2023:
2024: static int
1.410 djm 2025: channel_handle_efd_write(struct ssh *ssh, Channel *c)
1.367 djm 2026: {
2027: int r;
2028: ssize_t len;
2029:
1.410 djm 2030: if ((c->io_ready & SSH_CHAN_IO_EFD_W) == 0)
2031: return 1;
2032: if (sshbuf_len(c->extended) == 0)
1.367 djm 2033: return 1;
2034:
2035: len = write(c->efd, sshbuf_ptr(c->extended),
2036: sshbuf_len(c->extended));
2037: debug2("channel %d: written %zd to efd %d", c->self, len, c->efd);
1.393 deraadt 2038: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2039: return 1;
2040: if (len <= 0) {
2041: debug2("channel %d: closing write-efd %d", c->self, c->efd);
1.407 djm 2042: channel_close_fd(ssh, c, &c->efd);
1.367 djm 2043: } else {
1.403 djm 2044: if ((r = sshbuf_consume(c->extended, len)) != 0)
2045: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2046: c->local_consumed += len;
2047: }
1.44 markus 2048: return 1;
2049: }
1.241 deraadt 2050:
1.127 itojun 2051: static int
1.410 djm 2052: channel_handle_efd_read(struct ssh *ssh, Channel *c)
1.44 markus 2053: {
1.214 markus 2054: char buf[CHAN_RBUF];
1.367 djm 2055: int r;
2056: ssize_t len;
2057:
1.410 djm 2058: if ((c->io_ready & SSH_CHAN_IO_EFD_R) == 0)
1.367 djm 2059: return 1;
1.44 markus 2060:
1.367 djm 2061: len = read(c->efd, buf, sizeof(buf));
2062: debug2("channel %d: read %zd from efd %d", c->self, len, c->efd);
1.393 deraadt 2063: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2064: return 1;
2065: if (len <= 0) {
1.403 djm 2066: debug2("channel %d: closing read-efd %d", c->self, c->efd);
1.407 djm 2067: channel_close_fd(ssh, c, &c->efd);
1.403 djm 2068: } else if (c->extended_usage == CHAN_EXTENDED_IGNORE)
2069: debug3("channel %d: discard efd", c->self);
2070: else if ((r = sshbuf_put(c->extended, buf, len)) != 0)
2071: fatal_fr(r, "channel %i: append", c->self);
1.44 markus 2072: return 1;
2073: }
1.241 deraadt 2074:
1.127 itojun 2075: static int
1.410 djm 2076: channel_handle_efd(struct ssh *ssh, Channel *c)
1.44 markus 2077: {
1.367 djm 2078: if (c->efd == -1)
2079: return 1;
2080:
2081: /** XXX handle drain efd, too */
2082:
2083: if (c->extended_usage == CHAN_EXTENDED_WRITE)
1.410 djm 2084: return channel_handle_efd_write(ssh, c);
1.367 djm 2085: else if (c->extended_usage == CHAN_EXTENDED_READ ||
2086: c->extended_usage == CHAN_EXTENDED_IGNORE)
1.410 djm 2087: return channel_handle_efd_read(ssh, c);
1.367 djm 2088:
2089: return 1;
2090: }
2091:
2092: static int
2093: channel_check_window(struct ssh *ssh, Channel *c)
2094: {
2095: int r;
2096:
1.104 markus 2097: if (c->type == SSH_CHANNEL_OPEN &&
2098: !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
1.270 dtucker 2099: ((c->local_window_max - c->local_window >
1.269 markus 2100: c->local_maxpacket*3) ||
2101: c->local_window < c->local_window_max/2) &&
1.44 markus 2102: c->local_consumed > 0) {
1.368 djm 2103: if (!c->have_remote_id)
1.403 djm 2104: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2105: if ((r = sshpkt_start(ssh,
2106: SSH2_MSG_CHANNEL_WINDOW_ADJUST)) != 0 ||
2107: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2108: (r = sshpkt_put_u32(ssh, c->local_consumed)) != 0 ||
2109: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2110: fatal_fr(r, "channel %i", c->self);
1.367 djm 2111: }
1.403 djm 2112: debug2("channel %d: window %d sent adjust %d", c->self,
2113: c->local_window, c->local_consumed);
1.44 markus 2114: c->local_window += c->local_consumed;
2115: c->local_consumed = 0;
1.1 deraadt 2116: }
1.41 markus 2117: return 1;
1.1 deraadt 2118: }
2119:
1.127 itojun 2120: static void
1.410 djm 2121: channel_post_open(struct ssh *ssh, Channel *c)
1.41 markus 2122: {
1.410 djm 2123: channel_handle_rfd(ssh, c);
2124: channel_handle_wfd(ssh, c);
2125: channel_handle_efd(ssh, c);
1.367 djm 2126: channel_check_window(ssh, c);
1.44 markus 2127: }
2128:
1.302 djm 2129: static u_int
1.367 djm 2130: read_mux(struct ssh *ssh, Channel *c, u_int need)
1.302 djm 2131: {
2132: char buf[CHAN_RBUF];
1.367 djm 2133: ssize_t len;
1.302 djm 2134: u_int rlen;
1.367 djm 2135: int r;
1.302 djm 2136:
1.367 djm 2137: if (sshbuf_len(c->input) < need) {
2138: rlen = need - sshbuf_len(c->input);
1.352 deraadt 2139: len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF));
1.393 deraadt 2140: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2141: return sshbuf_len(c->input);
1.302 djm 2142: if (len <= 0) {
1.367 djm 2143: debug2("channel %d: ctl read<=0 rfd %d len %zd",
1.349 naddy 2144: c->self, c->rfd, len);
1.367 djm 2145: chan_read_failed(ssh, c);
1.349 naddy 2146: return 0;
1.403 djm 2147: } else if ((r = sshbuf_put(c->input, buf, len)) != 0)
2148: fatal_fr(r, "channel %i: append", c->self);
1.302 djm 2149: }
1.367 djm 2150: return sshbuf_len(c->input);
1.302 djm 2151: }
2152:
2153: static void
1.410 djm 2154: channel_post_mux_client_read(struct ssh *ssh, Channel *c)
1.302 djm 2155: {
2156: u_int need;
2157:
1.410 djm 2158: if ((c->io_ready & SSH_CHAN_IO_RFD) == 0)
1.367 djm 2159: return;
2160: if (c->istate != CHAN_INPUT_OPEN && c->istate != CHAN_INPUT_WAIT_DRAIN)
2161: return;
2162: if (c->mux_pause)
2163: return;
2164:
2165: /*
2166: * Don't not read past the precise end of packets to
2167: * avoid disrupting fd passing.
2168: */
2169: if (read_mux(ssh, c, 4) < 4) /* read header */
2170: return;
2171: /* XXX sshbuf_peek_u32 */
2172: need = PEEK_U32(sshbuf_ptr(c->input));
1.302 djm 2173: #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1.367 djm 2174: if (need > CHANNEL_MUX_MAX_PACKET) {
2175: debug2("channel %d: packet too big %u > %u",
2176: c->self, CHANNEL_MUX_MAX_PACKET, need);
2177: chan_rcvd_oclose(ssh, c);
2178: return;
2179: }
2180: if (read_mux(ssh, c, need + 4) < need + 4) /* read body */
2181: return;
2182: if (c->mux_rcb(ssh, c) != 0) {
2183: debug("channel %d: mux_rcb failed", c->self);
2184: chan_mark_dead(ssh, c);
2185: return;
1.302 djm 2186: }
1.367 djm 2187: }
2188:
2189: static void
1.410 djm 2190: channel_post_mux_client_write(struct ssh *ssh, Channel *c)
1.367 djm 2191: {
2192: ssize_t len;
2193: int r;
1.302 djm 2194:
1.410 djm 2195: if ((c->io_ready & SSH_CHAN_IO_WFD) == 0)
2196: return;
2197: if (sshbuf_len(c->output) == 0)
1.367 djm 2198: return;
2199:
2200: len = write(c->wfd, sshbuf_ptr(c->output), sshbuf_len(c->output));
1.393 deraadt 2201: if (len == -1 && (errno == EINTR || errno == EAGAIN))
1.367 djm 2202: return;
2203: if (len <= 0) {
2204: chan_mark_dead(ssh, c);
2205: return;
1.302 djm 2206: }
1.367 djm 2207: if ((r = sshbuf_consume(c->output, len)) != 0)
1.403 djm 2208: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2209: }
2210:
2211: static void
1.410 djm 2212: channel_post_mux_client(struct ssh *ssh, Channel *c)
1.367 djm 2213: {
1.410 djm 2214: channel_post_mux_client_read(ssh, c);
2215: channel_post_mux_client_write(ssh, c);
1.302 djm 2216: }
2217:
2218: static void
1.410 djm 2219: channel_post_mux_listener(struct ssh *ssh, Channel *c)
1.302 djm 2220: {
2221: Channel *nc;
2222: struct sockaddr_storage addr;
2223: socklen_t addrlen;
2224: int newsock;
2225: uid_t euid;
2226: gid_t egid;
2227:
1.410 djm 2228: if ((c->io_ready & SSH_CHAN_IO_SOCK_R) == 0)
1.302 djm 2229: return;
2230:
2231: debug("multiplexing control connection");
2232:
2233: /*
2234: * Accept connection on control socket
2235: */
2236: memset(&addr, 0, sizeof(addr));
2237: addrlen = sizeof(addr);
2238: if ((newsock = accept(c->sock, (struct sockaddr*)&addr,
2239: &addrlen)) == -1) {
1.403 djm 2240: error_f("accept: %s", strerror(errno));
1.317 djm 2241: if (errno == EMFILE || errno == ENFILE)
1.322 dtucker 2242: c->notbefore = monotime() + 1;
1.302 djm 2243: return;
2244: }
2245:
1.393 deraadt 2246: if (getpeereid(newsock, &euid, &egid) == -1) {
1.403 djm 2247: error_f("getpeereid failed: %s", strerror(errno));
1.302 djm 2248: close(newsock);
2249: return;
2250: }
2251: if ((euid != 0) && (getuid() != euid)) {
2252: error("multiplex uid mismatch: peer euid %u != uid %u",
2253: (u_int)euid, (u_int)getuid());
2254: close(newsock);
2255: return;
2256: }
1.367 djm 2257: nc = channel_new(ssh, "multiplex client", SSH_CHANNEL_MUX_CLIENT,
1.302 djm 2258: newsock, newsock, -1, c->local_window_max,
2259: c->local_maxpacket, 0, "mux-control", 1);
2260: nc->mux_rcb = c->mux_rcb;
1.403 djm 2261: debug3_f("new mux channel %d fd %d", nc->self, nc->sock);
1.302 djm 2262: /* establish state */
1.367 djm 2263: nc->mux_rcb(ssh, nc);
1.302 djm 2264: /* mux state transitions must not elicit protocol messages */
2265: nc->flags |= CHAN_LOCAL;
2266: }
2267:
1.127 itojun 2268: static void
1.367 djm 2269: channel_handler_init(struct ssh_channels *sc)
1.1 deraadt 2270: {
1.367 djm 2271: chan_fn **pre, **post;
2272:
2273: if ((pre = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*pre))) == NULL ||
1.406 djm 2274: (post = calloc(SSH_CHANNEL_MAX_TYPE, sizeof(*post))) == NULL)
1.403 djm 2275: fatal_f("allocation failed");
1.367 djm 2276:
2277: pre[SSH_CHANNEL_OPEN] = &channel_pre_open;
2278: pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
2279: pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
2280: pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
2281: pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener;
2282: pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener;
2283: pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
2284: pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
2285: pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
2286: pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
1.372 markus 2287: pre[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_pre_connecting;
1.367 djm 2288: pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener;
2289: pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client;
2290:
2291: post[SSH_CHANNEL_OPEN] = &channel_post_open;
2292: post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
2293: post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
2294: post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener;
2295: post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener;
2296: post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
2297: post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
2298: post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
2299: post[SSH_CHANNEL_DYNAMIC] = &channel_post_open;
1.372 markus 2300: post[SSH_CHANNEL_RDYNAMIC_FINISH] = &channel_post_connecting;
1.367 djm 2301: post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener;
2302: post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client;
1.180 deraadt 2303:
1.367 djm 2304: sc->channel_pre = pre;
2305: sc->channel_post = post;
1.44 markus 2306: }
2307:
1.140 markus 2308: /* gc dead channels */
2309: static void
1.367 djm 2310: channel_garbage_collect(struct ssh *ssh, Channel *c)
1.140 markus 2311: {
2312: if (c == NULL)
2313: return;
2314: if (c->detach_user != NULL) {
1.367 djm 2315: if (!chan_is_dead(ssh, c, c->detach_close))
1.140 markus 2316: return;
1.385 djm 2317:
1.194 markus 2318: debug2("channel %d: gc: notify user", c->self);
1.367 djm 2319: c->detach_user(ssh, c->self, NULL);
1.140 markus 2320: /* if we still have a callback */
2321: if (c->detach_user != NULL)
2322: return;
1.194 markus 2323: debug2("channel %d: gc: user detached", c->self);
1.140 markus 2324: }
1.367 djm 2325: if (!chan_is_dead(ssh, c, 1))
1.140 markus 2326: return;
1.194 markus 2327: debug2("channel %d: garbage collecting", c->self);
1.367 djm 2328: channel_free(ssh, c);
1.140 markus 2329: }
2330:
1.367 djm 2331: enum channel_table { CHAN_PRE, CHAN_POST };
2332:
1.127 itojun 2333: static void
1.410 djm 2334: channel_handler(struct ssh *ssh, int table, time_t *unpause_secs)
1.41 markus 2335: {
1.367 djm 2336: struct ssh_channels *sc = ssh->chanctxt;
2337: chan_fn **ftab = table == CHAN_PRE ? sc->channel_pre : sc->channel_post;
1.299 markus 2338: u_int i, oalloc;
1.41 markus 2339: Channel *c;
1.317 djm 2340: time_t now;
1.25 markus 2341:
1.322 dtucker 2342: now = monotime();
1.317 djm 2343: if (unpause_secs != NULL)
2344: *unpause_secs = 0;
1.367 djm 2345: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2346: c = sc->channels[i];
1.113 markus 2347: if (c == NULL)
1.41 markus 2348: continue;
1.299 markus 2349: if (c->delayed) {
1.367 djm 2350: if (table == CHAN_PRE)
1.299 markus 2351: c->delayed = 0;
2352: else
2353: continue;
2354: }
1.317 djm 2355: if (ftab[c->type] != NULL) {
2356: /*
2357: * Run handlers that are not paused.
2358: */
2359: if (c->notbefore <= now)
1.410 djm 2360: (*ftab[c->type])(ssh, c);
1.317 djm 2361: else if (unpause_secs != NULL) {
2362: /*
2363: * Collect the time that the earliest
2364: * channel comes off pause.
2365: */
1.403 djm 2366: debug3_f("chan %d: skip for %d more "
2367: "seconds", c->self,
1.317 djm 2368: (int)(c->notbefore - now));
2369: if (*unpause_secs == 0 ||
2370: (c->notbefore - now) < *unpause_secs)
2371: *unpause_secs = c->notbefore - now;
2372: }
2373: }
1.367 djm 2374: channel_garbage_collect(ssh, c);
1.1 deraadt 2375: }
1.317 djm 2376: if (unpause_secs != NULL && *unpause_secs != 0)
1.403 djm 2377: debug3_f("first channel unpauses in %d seconds",
2378: (int)*unpause_secs);
1.1 deraadt 2379: }
2380:
1.121 markus 2381: /*
1.411 ! djm 2382: * Create sockets before preparing IO.
1.372 markus 2383: * This is necessary for things that need to happen after reading
1.411 ! djm 2384: * the network-input but need to be completed before IO event setup, e.g.
! 2385: * because they may create new channels.
1.372 markus 2386: */
2387: static void
1.411 ! djm 2388: channel_before_prepare_io(struct ssh *ssh)
1.372 markus 2389: {
2390: struct ssh_channels *sc = ssh->chanctxt;
2391: Channel *c;
2392: u_int i, oalloc;
2393:
2394: for (i = 0, oalloc = sc->channels_alloc; i < oalloc; i++) {
2395: c = sc->channels[i];
2396: if (c == NULL)
2397: continue;
2398: if (c->type == SSH_CHANNEL_RDYNAMIC_OPEN)
1.411 ! djm 2399: channel_before_prepare_io_rdynamic(ssh, c);
! 2400: }
! 2401: }
! 2402:
! 2403: static void
! 2404: dump_channel_poll(const char *func, const char *what, Channel *c,
! 2405: u_int pollfd_offset, struct pollfd *pfd)
! 2406: {
! 2407: #ifdef DEBUG_CHANNEL_POLL
! 2408: debug3_f("channel %d: rfd r%d w%d e%d s%d "
! 2409: "pfd[%u].fd=%d want 0x%02x ev 0x%02x ready 0x%02x rev 0x%02x",
! 2410: c->self, c->rfd, c->wfd, c->efd, c->sock, pollfd_offset, pfd->fd,
! 2411: c->io_want, pfd->events, c->io_ready, pfd->revents);
! 2412: #endif
! 2413: }
! 2414:
! 2415: /* Prepare pollfd entries for a single channel */
! 2416: static void
! 2417: channel_prepare_pollfd(Channel *c, u_int *next_pollfd,
! 2418: struct pollfd *pfd, u_int npfd)
! 2419: {
! 2420: u_int p = *next_pollfd;
! 2421:
! 2422: if (c == NULL)
! 2423: return;
! 2424: if (p + 4 > npfd) {
! 2425: /* Shouldn't happen */
! 2426: fatal_f("channel %d: bad pfd offset %u (max %u)",
! 2427: c->self, p, npfd);
! 2428: }
! 2429: c->pollfd_offset = -1;
! 2430: /*
! 2431: * prepare c->rfd
! 2432: *
! 2433: * This is a special case, since c->rfd might be the same as
! 2434: * c->wfd, c->efd and/or c->sock. Handle those here if they want
! 2435: * IO too.
! 2436: */
! 2437: if (c->rfd != -1) {
! 2438: if (c->pollfd_offset == -1)
! 2439: c->pollfd_offset = p;
! 2440: pfd[p].fd = c->rfd;
! 2441: pfd[p].events = 0;
! 2442: if ((c->io_want & SSH_CHAN_IO_RFD) != 0)
! 2443: pfd[p].events |= POLLIN;
! 2444: /* rfd == wfd */
! 2445: if (c->wfd == c->rfd &&
! 2446: (c->io_want & SSH_CHAN_IO_WFD) != 0)
! 2447: pfd[p].events |= POLLOUT;
! 2448: /* rfd == efd */
! 2449: if (c->efd == c->rfd &&
! 2450: (c->io_want & SSH_CHAN_IO_EFD_R) != 0)
! 2451: pfd[p].events |= POLLIN;
! 2452: if (c->efd == c->rfd &&
! 2453: (c->io_want & SSH_CHAN_IO_EFD_W) != 0)
! 2454: pfd[p].events |= POLLOUT;
! 2455: /* rfd == sock */
! 2456: if (c->sock == c->rfd &&
! 2457: (c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
! 2458: pfd[p].events |= POLLIN;
! 2459: if (c->sock == c->rfd &&
! 2460: (c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
! 2461: pfd[p].events |= POLLOUT;
! 2462: dump_channel_poll(__func__, "rfd", c, p, &pfd[p]);
! 2463: p++;
! 2464: }
! 2465: /* prepare c->wfd (if not already handled above) */
! 2466: if (c->wfd != -1 && c->rfd != c->wfd) {
! 2467: if (c->pollfd_offset == -1)
! 2468: c->pollfd_offset = p;
! 2469: pfd[p].fd = c->wfd;
! 2470: pfd[p].events = 0;
! 2471: if ((c->io_want & SSH_CHAN_IO_WFD) != 0)
! 2472: pfd[p].events = POLLOUT;
! 2473: dump_channel_poll(__func__, "wfd", c, p, &pfd[p]);
! 2474: p++;
! 2475: }
! 2476: /* prepare c->efd (if not already handled above) */
! 2477: if (c->efd != -1 && c->rfd != c->efd) {
! 2478: if (c->pollfd_offset == -1)
! 2479: c->pollfd_offset = p;
! 2480: pfd[p].fd = c->efd;
! 2481: pfd[p].events = 0;
! 2482: if ((c->io_want & SSH_CHAN_IO_EFD_R) != 0)
! 2483: pfd[p].events |= POLLIN;
! 2484: if ((c->io_want & SSH_CHAN_IO_EFD_W) != 0)
! 2485: pfd[p].events |= POLLOUT;
! 2486: dump_channel_poll(__func__, "efd", c, p, &pfd[p]);
! 2487: p++;
! 2488: }
! 2489: /* prepare c->sock (if not already handled above) */
! 2490: if (c->sock != -1 && c->rfd != c->sock) {
! 2491: if (c->pollfd_offset == -1)
! 2492: c->pollfd_offset = p;
! 2493: pfd[p].fd = c->sock;
! 2494: pfd[p].events = 0;
! 2495: if ((c->io_want & SSH_CHAN_IO_SOCK_R) != 0)
! 2496: pfd[p].events |= POLLIN;
! 2497: if ((c->io_want & SSH_CHAN_IO_SOCK_W) != 0)
! 2498: pfd[p].events |= POLLOUT;
! 2499: dump_channel_poll(__func__, "sock", c, p, &pfd[p]);
! 2500: p++;
1.372 markus 2501: }
1.411 ! djm 2502: *next_pollfd = p;
1.372 markus 2503: }
2504:
1.411 ! djm 2505: /* * Allocate/prepare poll structure */
1.49 markus 2506: void
1.411 ! djm 2507: channel_prepare_poll(struct ssh *ssh, struct pollfd **pfdp, u_int *npfd_allocp,
! 2508: u_int *npfd_activep, u_int npfd_reserved, time_t *minwait_secs)
1.41 markus 2509: {
1.410 djm 2510: struct ssh_channels *sc = ssh->chanctxt;
1.411 ! djm 2511: u_int i, oalloc, p, npfd = npfd_reserved;
! 2512:
! 2513: channel_before_prepare_io(ssh); /* might create a new channel */
! 2514:
! 2515: /* Allocate 4x pollfd for each channel (rfd, wfd, efd, sock) */
! 2516: if (sc->channels_alloc >= (INT_MAX / 4) - npfd_reserved)
! 2517: fatal_f("too many channels"); /* shouldn't happen */
! 2518: if (!ssh_packet_is_rekeying(ssh))
! 2519: npfd += sc->channels_alloc * 4;
! 2520: if (npfd > *npfd_allocp) {
! 2521: *pfdp = xrecallocarray(*pfdp, *npfd_allocp,
! 2522: npfd, sizeof(**pfdp));
! 2523: *npfd_allocp = npfd;
! 2524: }
! 2525: *npfd_activep = npfd_reserved;
! 2526: if (ssh_packet_is_rekeying(ssh))
! 2527: return;
1.84 markus 2528:
1.411 ! djm 2529: oalloc = sc->channels_alloc;
1.372 markus 2530:
1.411 ! djm 2531: channel_handler(ssh, CHAN_PRE, minwait_secs);
1.84 markus 2532:
1.411 ! djm 2533: if (oalloc != sc->channels_alloc) {
! 2534: /* shouldn't happen */
! 2535: fatal_f("channels_alloc changed during CHAN_PRE "
! 2536: "(was %u, now %u)", oalloc, sc->channels_alloc);
! 2537: }
1.84 markus 2538:
1.411 ! djm 2539: /* Prepare pollfd */
! 2540: p = npfd_reserved;
! 2541: for (i = 0; i < sc->channels_alloc; i++)
! 2542: channel_prepare_pollfd(sc->channels[i], &p, *pfdp, npfd);
! 2543: *npfd_activep = p;
! 2544: }
! 2545:
! 2546: static void
! 2547: fd_ready(Channel *c, u_int p, struct pollfd *pfds, int fd,
! 2548: const char *what, u_int revents_mask, u_int ready)
! 2549: {
! 2550: struct pollfd *pfd = &pfds[p];
1.410 djm 2551:
1.411 ! djm 2552: if (fd == -1)
! 2553: return;
! 2554: dump_channel_poll(__func__, what, c, p, pfd);
! 2555: if (pfd->fd != fd) {
! 2556: fatal("channel %d: inconsistent %s fd=%d pollfd[%u].fd %d "
! 2557: "r%d w%d e%d s%d", c->self, what, fd, p, pfd->fd,
! 2558: c->rfd, c->wfd, c->efd, c->sock);
! 2559: }
! 2560: if ((pfd->revents & POLLNVAL) != 0) {
! 2561: fatal("channel %d: invalid %s pollfd[%u].fd %d r%d w%d e%d s%d",
! 2562: c->self, what, p, pfd->fd, c->rfd, c->wfd, c->efd, c->sock);
1.410 djm 2563: }
1.411 ! djm 2564: if ((pfd->revents & (revents_mask|POLLHUP|POLLERR)) != 0)
! 2565: c->io_ready |= ready & c->io_want;
1.41 markus 2566: }
2567:
1.121 markus 2568: /*
1.411 ! djm 2569: * After poll, perform any appropriate operations for channels which have
1.121 markus 2570: * events pending.
2571: */
1.49 markus 2572: void
1.411 ! djm 2573: channel_after_poll(struct ssh *ssh, struct pollfd *pfd, u_int npfd)
1.41 markus 2574: {
1.410 djm 2575: struct ssh_channels *sc = ssh->chanctxt;
1.411 ! djm 2576: u_int i, p;
1.410 djm 2577: Channel *c;
2578:
1.411 ! djm 2579: #ifdef DEBUG_CHANNEL_POLL
! 2580: for (p = 0; p < npfd; p++) {
! 2581: if (pfd[p].revents == 0)
! 2582: continue;
! 2583: debug_f("pfd[%u].fd %d rev 0x%04x",
! 2584: p, pfd[p].fd, pfd[p].revents);
! 2585: }
! 2586: #endif
! 2587:
! 2588: /* Convert pollfd into c->io_ready */
! 2589: for (i = 0; i < sc->channels_alloc; i++) {
1.410 djm 2590: c = sc->channels[i];
1.411 ! djm 2591: if (c == NULL || c->pollfd_offset < 0)
1.410 djm 2592: continue;
1.411 ! djm 2593: if ((u_int)c->pollfd_offset >= npfd) {
! 2594: /* shouldn't happen */
! 2595: fatal_f("channel %d: (before) bad pfd %u (max %u)",
! 2596: c->self, c->pollfd_offset, npfd);
! 2597: }
! 2598: /* if rfd is shared with efd/sock then wfd should be too */
! 2599: if (c->rfd != -1 && c->wfd != -1 && c->rfd != c->wfd &&
! 2600: (c->rfd == c->efd || c->rfd == c->sock)) {
! 2601: /* Shouldn't happen */
! 2602: fatal_f("channel %d: unexpected fds r%d w%d e%d s%d",
! 2603: c->self, c->rfd, c->wfd, c->efd, c->sock);
! 2604: }
1.410 djm 2605: c->io_ready = 0;
1.411 ! djm 2606: p = c->pollfd_offset;
! 2607: /* rfd, potentially shared with wfd, efd and sock */
! 2608: if (c->rfd != -1) {
! 2609: fd_ready(c, p, pfd, c->rfd, "rfd", POLLIN,
! 2610: SSH_CHAN_IO_RFD);
! 2611: if (c->rfd == c->wfd) {
! 2612: fd_ready(c, p, pfd, c->wfd, "wfd/r", POLLOUT,
! 2613: SSH_CHAN_IO_WFD);
! 2614: }
! 2615: if (c->rfd == c->efd) {
! 2616: fd_ready(c, p, pfd, c->efd, "efdr/r", POLLIN,
! 2617: SSH_CHAN_IO_EFD_R);
! 2618: fd_ready(c, p, pfd, c->efd, "efdw/r", POLLOUT,
! 2619: SSH_CHAN_IO_EFD_W);
! 2620: }
! 2621: if (c->rfd == c->sock) {
! 2622: fd_ready(c, p, pfd, c->sock, "sockr/r", POLLIN,
! 2623: SSH_CHAN_IO_SOCK_R);
! 2624: fd_ready(c, p, pfd, c->sock, "sockw/r", POLLOUT,
! 2625: SSH_CHAN_IO_SOCK_W);
! 2626: }
! 2627: p++;
! 2628: }
! 2629: /* wfd */
! 2630: if (c->wfd != -1 && c->wfd != c->rfd) {
! 2631: fd_ready(c, p, pfd, c->wfd, "wfd", POLLOUT,
! 2632: SSH_CHAN_IO_WFD);
! 2633: p++;
! 2634: }
! 2635: /* efd */
! 2636: if (c->efd != -1 && c->efd != c->rfd) {
! 2637: fd_ready(c, p, pfd, c->efd, "efdr", POLLIN,
! 2638: SSH_CHAN_IO_EFD_R);
! 2639: fd_ready(c, p, pfd, c->efd, "efdw", POLLOUT,
! 2640: SSH_CHAN_IO_EFD_W);
! 2641: p++;
! 2642: }
! 2643: /* sock */
! 2644: if (c->sock != -1 && c->sock != c->rfd) {
! 2645: fd_ready(c, p, pfd, c->sock, "sockr", POLLIN,
! 2646: SSH_CHAN_IO_SOCK_R);
! 2647: fd_ready(c, p, pfd, c->sock, "sockw", POLLOUT,
! 2648: SSH_CHAN_IO_SOCK_W);
! 2649: p++;
! 2650: }
! 2651:
! 2652: if (p > npfd) {
! 2653: /* shouldn't happen */
! 2654: fatal_f("channel %d: (after) bad pfd %u (max %u)",
! 2655: c->self, c->pollfd_offset, npfd);
! 2656: }
1.410 djm 2657: }
2658: channel_handler(ssh, CHAN_POST, NULL);
1.367 djm 2659: }
2660:
2661: /*
2662: * Enqueue data for channels with open or draining c->input.
2663: */
2664: static void
2665: channel_output_poll_input_open(struct ssh *ssh, Channel *c)
2666: {
1.373 djm 2667: size_t len, plen;
2668: const u_char *pkt;
1.367 djm 2669: int r;
2670:
2671: if ((len = sshbuf_len(c->input)) == 0) {
2672: if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
2673: /*
2674: * input-buffer is empty and read-socket shutdown:
2675: * tell peer, that we will not send more data:
2676: * send IEOF.
2677: * hack for extended data: delay EOF if EFD still
2678: * in use.
2679: */
2680: if (CHANNEL_EFD_INPUT_ACTIVE(c))
2681: debug2("channel %d: "
2682: "ibuf_empty delayed efd %d/(%zu)",
2683: c->self, c->efd, sshbuf_len(c->extended));
2684: else
2685: chan_ibuf_empty(ssh, c);
2686: }
2687: return;
2688: }
2689:
1.368 djm 2690: if (!c->have_remote_id)
1.403 djm 2691: fatal_f("channel %d: no remote id", c->self);
1.368 djm 2692:
1.367 djm 2693: if (c->datagram) {
2694: /* Check datagram will fit; drop if not */
1.373 djm 2695: if ((r = sshbuf_get_string_direct(c->input, &pkt, &plen)) != 0)
1.403 djm 2696: fatal_fr(r, "channel %i: get datagram", c->self);
1.367 djm 2697: /*
2698: * XXX this does tail-drop on the datagram queue which is
2699: * usually suboptimal compared to head-drop. Better to have
2700: * backpressure at read time? (i.e. read + discard)
2701: */
1.373 djm 2702: if (plen > c->remote_window || plen > c->remote_maxpacket) {
1.367 djm 2703: debug("channel %d: datagram too big", c->self);
2704: return;
2705: }
2706: /* Enqueue it */
2707: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2708: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
1.373 djm 2709: (r = sshpkt_put_string(ssh, pkt, plen)) != 0 ||
1.403 djm 2710: (r = sshpkt_send(ssh)) != 0)
2711: fatal_fr(r, "channel %i: send datagram", c->self);
1.373 djm 2712: c->remote_window -= plen;
1.367 djm 2713: return;
2714: }
2715:
2716: /* Enqueue packet for buffered data. */
2717: if (len > c->remote_window)
2718: len = c->remote_window;
2719: if (len > c->remote_maxpacket)
2720: len = c->remote_maxpacket;
2721: if (len == 0)
2722: return;
2723: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_DATA)) != 0 ||
2724: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2725: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->input), len)) != 0 ||
1.403 djm 2726: (r = sshpkt_send(ssh)) != 0)
2727: fatal_fr(r, "channel %i: send data", c->self);
1.367 djm 2728: if ((r = sshbuf_consume(c->input, len)) != 0)
1.403 djm 2729: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2730: c->remote_window -= len;
1.41 markus 2731: }
2732:
1.367 djm 2733: /*
2734: * Enqueue data for channels with open c->extended in read mode.
2735: */
2736: static void
2737: channel_output_poll_extended_read(struct ssh *ssh, Channel *c)
2738: {
2739: size_t len;
2740: int r;
2741:
2742: if ((len = sshbuf_len(c->extended)) == 0)
2743: return;
2744:
2745: debug2("channel %d: rwin %u elen %zu euse %d", c->self,
2746: c->remote_window, sshbuf_len(c->extended), c->extended_usage);
2747: if (len > c->remote_window)
2748: len = c->remote_window;
2749: if (len > c->remote_maxpacket)
2750: len = c->remote_maxpacket;
2751: if (len == 0)
2752: return;
1.368 djm 2753: if (!c->have_remote_id)
1.403 djm 2754: fatal_f("channel %d: no remote id", c->self);
1.367 djm 2755: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_EXTENDED_DATA)) != 0 ||
2756: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
2757: (r = sshpkt_put_u32(ssh, SSH2_EXTENDED_DATA_STDERR)) != 0 ||
2758: (r = sshpkt_put_string(ssh, sshbuf_ptr(c->extended), len)) != 0 ||
1.403 djm 2759: (r = sshpkt_send(ssh)) != 0)
2760: fatal_fr(r, "channel %i: data", c->self);
1.367 djm 2761: if ((r = sshbuf_consume(c->extended, len)) != 0)
1.403 djm 2762: fatal_fr(r, "channel %i: consume", c->self);
1.367 djm 2763: c->remote_window -= len;
2764: debug2("channel %d: sent ext data %zu", c->self, len);
2765: }
1.121 markus 2766:
1.84 markus 2767: /* If there is data to send to the connection, enqueue some of it now. */
1.49 markus 2768: void
1.367 djm 2769: channel_output_poll(struct ssh *ssh)
1.1 deraadt 2770: {
1.367 djm 2771: struct ssh_channels *sc = ssh->chanctxt;
1.41 markus 2772: Channel *c;
1.367 djm 2773: u_int i;
1.1 deraadt 2774:
1.367 djm 2775: for (i = 0; i < sc->channels_alloc; i++) {
2776: c = sc->channels[i];
1.113 markus 2777: if (c == NULL)
2778: continue;
1.37 markus 2779:
1.121 markus 2780: /*
2781: * We are only interested in channels that can have buffered
2782: * incoming data.
2783: */
1.358 djm 2784: if (c->type != SSH_CHANNEL_OPEN)
2785: continue;
2786: if ((c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1.93 markus 2787: /* XXX is this true? */
1.367 djm 2788: debug3("channel %d: will not send data after close",
2789: c->self);
1.44 markus 2790: continue;
2791: }
1.25 markus 2792:
2793: /* Get the amount of buffered data for this channel. */
1.367 djm 2794: if (c->istate == CHAN_INPUT_OPEN ||
2795: c->istate == CHAN_INPUT_WAIT_DRAIN)
2796: channel_output_poll_input_open(ssh, c);
1.44 markus 2797: /* Send extended data, i.e. stderr */
1.358 djm 2798: if (!(c->flags & CHAN_EOF_SENT) &&
1.367 djm 2799: c->extended_usage == CHAN_EXTENDED_READ)
2800: channel_output_poll_extended_read(ssh, c);
1.25 markus 2801: }
1.1 deraadt 2802: }
2803:
1.354 markus 2804: /* -- mux proxy support */
2805:
2806: /*
2807: * When multiplexing channel messages for mux clients we have to deal
2808: * with downstream messages from the mux client and upstream messages
2809: * from the ssh server:
2810: * 1) Handling downstream messages is straightforward and happens
2811: * in channel_proxy_downstream():
2812: * - We forward all messages (mostly) unmodified to the server.
2813: * - However, in order to route messages from upstream to the correct
2814: * downstream client, we have to replace the channel IDs used by the
2815: * mux clients with a unique channel ID because the mux clients might
2816: * use conflicting channel IDs.
2817: * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and
2818: * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local
2819: * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID
2820: * with the newly allocated channel ID.
2821: * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY
1.380 djm 2822: * channels and processed by channel_proxy_upstream(). The local channel ID
1.354 markus 2823: * is then translated back to the original mux client ID.
2824: * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE
2825: * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels.
2826: * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the
2827: * downstream mux client are removed.
2828: * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server
2829: * requires more work, because they are not addressed to a specific
2830: * channel. E.g. client_request_forwarded_tcpip() needs to figure
2831: * out whether the request is addressed to the local client or a
2832: * specific downstream client based on the listen-address/port.
1.380 djm 2833: * 6) Agent and X11-Forwarding have a similar problem and are currently
1.354 markus 2834: * not supported as the matching session/channel cannot be identified
2835: * easily.
2836: */
2837:
2838: /*
2839: * receive packets from downstream mux clients:
2840: * channel callback fired on read from mux client, creates
2841: * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs
2842: * on channel creation.
2843: */
2844: int
1.367 djm 2845: channel_proxy_downstream(struct ssh *ssh, Channel *downstream)
1.354 markus 2846: {
2847: Channel *c = NULL;
2848: struct sshbuf *original = NULL, *modified = NULL;
2849: const u_char *cp;
2850: char *ctype = NULL, *listen_host = NULL;
2851: u_char type;
2852: size_t have;
1.370 djm 2853: int ret = -1, r;
1.355 djm 2854: u_int id, remote_id, listen_port;
1.354 markus 2855:
1.367 djm 2856: /* sshbuf_dump(downstream->input, stderr); */
2857: if ((r = sshbuf_get_string_direct(downstream->input, &cp, &have))
1.354 markus 2858: != 0) {
1.403 djm 2859: error_fr(r, "parse");
1.354 markus 2860: return -1;
2861: }
2862: if (have < 2) {
1.403 djm 2863: error_f("short message");
1.354 markus 2864: return -1;
2865: }
2866: type = cp[1];
2867: /* skip padlen + type */
2868: cp += 2;
2869: have -= 2;
2870: if (ssh_packet_log_type(type))
1.403 djm 2871: debug3_f("channel %u: down->up: type %u",
1.354 markus 2872: downstream->self, type);
2873:
2874: switch (type) {
2875: case SSH2_MSG_CHANNEL_OPEN:
2876: if ((original = sshbuf_from(cp, have)) == NULL ||
2877: (modified = sshbuf_new()) == NULL) {
1.403 djm 2878: error_f("alloc");
1.354 markus 2879: goto out;
2880: }
2881: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 ||
2882: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2883: error_fr(r, "parse");
1.354 markus 2884: goto out;
2885: }
1.367 djm 2886: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2887: -1, -1, -1, 0, 0, 0, ctype, 1);
1.354 markus 2888: c->mux_ctx = downstream; /* point to mux client */
2889: c->mux_downstream_id = id; /* original downstream id */
2890: if ((r = sshbuf_put_cstring(modified, ctype)) != 0 ||
2891: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2892: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2893: error_fr(r, "compose");
1.367 djm 2894: channel_free(ssh, c);
1.354 markus 2895: goto out;
2896: }
2897: break;
2898: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
2899: /*
2900: * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we
2901: * need to parse 'remote_id' instead of 'ctype'.
2902: */
2903: if ((original = sshbuf_from(cp, have)) == NULL ||
2904: (modified = sshbuf_new()) == NULL) {
1.403 djm 2905: error_f("alloc");
1.354 markus 2906: goto out;
2907: }
2908: if ((r = sshbuf_get_u32(original, &remote_id)) != 0 ||
2909: (r = sshbuf_get_u32(original, &id)) != 0) {
1.403 djm 2910: error_fr(r, "parse");
1.354 markus 2911: goto out;
2912: }
1.367 djm 2913: c = channel_new(ssh, "mux proxy", SSH_CHANNEL_MUX_PROXY,
1.406 djm 2914: -1, -1, -1, 0, 0, 0, "mux-down-connect", 1);
1.354 markus 2915: c->mux_ctx = downstream; /* point to mux client */
2916: c->mux_downstream_id = id;
2917: c->remote_id = remote_id;
1.368 djm 2918: c->have_remote_id = 1;
1.354 markus 2919: if ((r = sshbuf_put_u32(modified, remote_id)) != 0 ||
2920: (r = sshbuf_put_u32(modified, c->self)) != 0 ||
2921: (r = sshbuf_putb(modified, original)) != 0) {
1.403 djm 2922: error_fr(r, "compose");
1.367 djm 2923: channel_free(ssh, c);
1.354 markus 2924: goto out;
2925: }
2926: break;
2927: case SSH2_MSG_GLOBAL_REQUEST:
2928: if ((original = sshbuf_from(cp, have)) == NULL) {
1.403 djm 2929: error_f("alloc");
1.354 markus 2930: goto out;
2931: }
2932: if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) {
1.403 djm 2933: error_fr(r, "parse");
1.354 markus 2934: goto out;
2935: }
2936: if (strcmp(ctype, "tcpip-forward") != 0) {
1.403 djm 2937: error_f("unsupported request %s", ctype);
1.354 markus 2938: goto out;
2939: }
2940: if ((r = sshbuf_get_u8(original, NULL)) != 0 ||
2941: (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 ||
2942: (r = sshbuf_get_u32(original, &listen_port)) != 0) {
1.403 djm 2943: error_fr(r, "parse");
1.354 markus 2944: goto out;
2945: }
1.355 djm 2946: if (listen_port > 65535) {
1.403 djm 2947: error_f("tcpip-forward for %s: bad port %u",
2948: listen_host, listen_port);
1.355 djm 2949: goto out;
2950: }
1.354 markus 2951: /* Record that connection to this host/port is permitted. */
1.381 djm 2952: permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL, "<mux>", -1,
1.367 djm 2953: listen_host, NULL, (int)listen_port, downstream);
1.354 markus 2954: listen_host = NULL;
2955: break;
2956: case SSH2_MSG_CHANNEL_CLOSE:
2957: if (have < 4)
2958: break;
2959: remote_id = PEEK_U32(cp);
1.367 djm 2960: if ((c = channel_by_remote_id(ssh, remote_id)) != NULL) {
1.354 markus 2961: if (c->flags & CHAN_CLOSE_RCVD)
1.367 djm 2962: channel_free(ssh, c);
1.354 markus 2963: else
2964: c->flags |= CHAN_CLOSE_SENT;
2965: }
2966: break;
2967: }
2968: if (modified) {
2969: if ((r = sshpkt_start(ssh, type)) != 0 ||
2970: (r = sshpkt_putb(ssh, modified)) != 0 ||
2971: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2972: error_fr(r, "send");
1.354 markus 2973: goto out;
2974: }
2975: } else {
2976: if ((r = sshpkt_start(ssh, type)) != 0 ||
2977: (r = sshpkt_put(ssh, cp, have)) != 0 ||
2978: (r = sshpkt_send(ssh)) != 0) {
1.403 djm 2979: error_fr(r, "send");
1.354 markus 2980: goto out;
2981: }
2982: }
2983: ret = 0;
2984: out:
2985: free(ctype);
2986: free(listen_host);
2987: sshbuf_free(original);
2988: sshbuf_free(modified);
2989: return ret;
2990: }
2991:
2992: /*
2993: * receive packets from upstream server and de-multiplex packets
2994: * to correct downstream:
2995: * implemented as a helper for channel input handlers,
2996: * replaces local (proxy) channel ID with downstream channel ID.
2997: */
2998: int
1.363 markus 2999: channel_proxy_upstream(Channel *c, int type, u_int32_t seq, struct ssh *ssh)
1.354 markus 3000: {
3001: struct sshbuf *b = NULL;
3002: Channel *downstream;
3003: const u_char *cp = NULL;
3004: size_t len;
3005: int r;
3006:
3007: /*
3008: * When receiving packets from the peer we need to check whether we
3009: * need to forward the packets to the mux client. In this case we
1.380 djm 3010: * restore the original channel id and keep track of CLOSE messages,
1.354 markus 3011: * so we can cleanup the channel.
3012: */
3013: if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY)
3014: return 0;
3015: if ((downstream = c->mux_ctx) == NULL)
3016: return 0;
3017: switch (type) {
3018: case SSH2_MSG_CHANNEL_CLOSE:
3019: case SSH2_MSG_CHANNEL_DATA:
3020: case SSH2_MSG_CHANNEL_EOF:
3021: case SSH2_MSG_CHANNEL_EXTENDED_DATA:
3022: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3023: case SSH2_MSG_CHANNEL_OPEN_FAILURE:
3024: case SSH2_MSG_CHANNEL_WINDOW_ADJUST:
3025: case SSH2_MSG_CHANNEL_SUCCESS:
3026: case SSH2_MSG_CHANNEL_FAILURE:
3027: case SSH2_MSG_CHANNEL_REQUEST:
3028: break;
3029: default:
1.403 djm 3030: debug2_f("channel %u: unsupported type %u", c->self, type);
1.354 markus 3031: return 0;
3032: }
3033: if ((b = sshbuf_new()) == NULL) {
1.403 djm 3034: error_f("alloc reply");
1.354 markus 3035: goto out;
3036: }
3037: /* get remaining payload (after id) */
3038: cp = sshpkt_ptr(ssh, &len);
3039: if (cp == NULL) {
1.403 djm 3040: error_f("no packet");
1.354 markus 3041: goto out;
3042: }
3043: /* translate id and send to muxclient */
3044: if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */
3045: (r = sshbuf_put_u8(b, type)) != 0 ||
3046: (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 ||
3047: (r = sshbuf_put(b, cp, len)) != 0 ||
1.367 djm 3048: (r = sshbuf_put_stringb(downstream->output, b)) != 0) {
1.403 djm 3049: error_fr(r, "compose muxclient");
1.354 markus 3050: goto out;
3051: }
3052: /* sshbuf_dump(b, stderr); */
3053: if (ssh_packet_log_type(type))
1.403 djm 3054: debug3_f("channel %u: up->down: type %u", c->self, type);
1.354 markus 3055: out:
3056: /* update state */
3057: switch (type) {
3058: case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION:
3059: /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */
1.368 djm 3060: if (cp && len > 4) {
1.354 markus 3061: c->remote_id = PEEK_U32(cp);
1.368 djm 3062: c->have_remote_id = 1;
3063: }
1.354 markus 3064: break;
3065: case SSH2_MSG_CHANNEL_CLOSE:
3066: if (c->flags & CHAN_CLOSE_SENT)
1.367 djm 3067: channel_free(ssh, c);
1.354 markus 3068: else
3069: c->flags |= CHAN_CLOSE_RCVD;
3070: break;
3071: }
3072: sshbuf_free(b);
3073: return 1;
3074: }
1.121 markus 3075:
3076: /* -- protocol input */
1.249 djm 3077:
1.367 djm 3078: /* Parse a channel ID from the current packet */
3079: static int
3080: channel_parse_id(struct ssh *ssh, const char *where, const char *what)
3081: {
3082: u_int32_t id;
3083: int r;
3084:
3085: if ((r = sshpkt_get_u32(ssh, &id)) != 0) {
1.403 djm 3086: error_r(r, "%s: parse id", where);
1.367 djm 3087: ssh_packet_disconnect(ssh, "Invalid %s message", what);
3088: }
3089: if (id > INT_MAX) {
1.403 djm 3090: error_r(r, "%s: bad channel id %u", where, id);
1.367 djm 3091: ssh_packet_disconnect(ssh, "Invalid %s channel id", what);
3092: }
3093: return (int)id;
3094: }
3095:
3096: /* Lookup a channel from an ID in the current packet */
3097: static Channel *
3098: channel_from_packet_id(struct ssh *ssh, const char *where, const char *what)
3099: {
3100: int id = channel_parse_id(ssh, where, what);
3101: Channel *c;
3102:
3103: if ((c = channel_lookup(ssh, id)) == NULL) {
3104: ssh_packet_disconnect(ssh,
3105: "%s packet referred to nonexistent channel %d", what, id);
3106: }
3107: return c;
3108: }
3109:
1.339 markus 3110: int
1.363 markus 3111: channel_input_data(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3112: {
1.332 djm 3113: const u_char *data;
1.367 djm 3114: size_t data_len, win_len;
3115: Channel *c = channel_from_packet_id(ssh, __func__, "data");
3116: int r;
1.25 markus 3117:
1.363 markus 3118: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3119: return 0;
1.25 markus 3120:
3121: /* Ignore any data for non-open channels (might happen on close) */
1.41 markus 3122: if (c->type != SSH_CHANNEL_OPEN &&
1.372 markus 3123: c->type != SSH_CHANNEL_RDYNAMIC_OPEN &&
3124: c->type != SSH_CHANNEL_RDYNAMIC_FINISH &&
1.41 markus 3125: c->type != SSH_CHANNEL_X11_OPEN)
1.339 markus 3126: return 0;
1.37 markus 3127:
1.25 markus 3128: /* Get the data. */
1.389 djm 3129: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3130: (r = sshpkt_get_end(ssh)) != 0)
1.403 djm 3131: fatal_fr(r, "channel %i: get data", c->self);
1.367 djm 3132:
1.309 djm 3133: win_len = data_len;
3134: if (c->datagram)
3135: win_len += 4; /* string length header */
1.200 markus 3136:
3137: /*
1.367 djm 3138: * The sending side reduces its window as it sends data, so we
3139: * must 'fake' consumption of the data in order to ensure that window
3140: * updates are sent back. Otherwise the connection might deadlock.
1.200 markus 3141: */
1.358 djm 3142: if (c->ostate != CHAN_OUTPUT_OPEN) {
3143: c->local_window -= win_len;
3144: c->local_consumed += win_len;
1.339 markus 3145: return 0;
1.200 markus 3146: }
1.41 markus 3147:
1.358 djm 3148: if (win_len > c->local_maxpacket) {
1.367 djm 3149: logit("channel %d: rcvd big packet %zu, maxpack %u",
1.358 djm 3150: c->self, win_len, c->local_maxpacket);
1.367 djm 3151: return 0;
1.358 djm 3152: }
3153: if (win_len > c->local_window) {
1.367 djm 3154: logit("channel %d: rcvd too much data %zu, win %u",
1.358 djm 3155: c->self, win_len, c->local_window);
3156: return 0;
1.44 markus 3157: }
1.358 djm 3158: c->local_window -= win_len;
3159:
1.367 djm 3160: if (c->datagram) {
3161: if ((r = sshbuf_put_string(c->output, data, data_len)) != 0)
1.403 djm 3162: fatal_fr(r, "channel %i: append datagram", c->self);
1.367 djm 3163: } else if ((r = sshbuf_put(c->output, data, data_len)) != 0)
1.403 djm 3164: fatal_fr(r, "channel %i: append data", c->self);
1.367 djm 3165:
1.339 markus 3166: return 0;
1.1 deraadt 3167: }
1.121 markus 3168:
1.339 markus 3169: int
1.363 markus 3170: channel_input_extended_data(int type, u_int32_t seq, struct ssh *ssh)
1.44 markus 3171: {
1.367 djm 3172: const u_char *data;
3173: size_t data_len;
3174: u_int32_t tcode;
3175: Channel *c = channel_from_packet_id(ssh, __func__, "extended data");
3176: int r;
1.44 markus 3177:
1.363 markus 3178: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3179: return 0;
1.44 markus 3180: if (c->type != SSH_CHANNEL_OPEN) {
1.367 djm 3181: logit("channel %d: ext data for non open", c->self);
1.339 markus 3182: return 0;
1.172 markus 3183: }
3184: if (c->flags & CHAN_EOF_RCVD) {
1.404 djm 3185: if (ssh->compat & SSH_BUG_EXTEOF)
1.367 djm 3186: debug("channel %d: accepting ext data after eof",
3187: c->self);
1.172 markus 3188: else
1.367 djm 3189: ssh_packet_disconnect(ssh, "Received extended_data "
3190: "after EOF on channel %d.", c->self);
3191: }
3192:
3193: if ((r = sshpkt_get_u32(ssh, &tcode)) != 0) {
1.403 djm 3194: error_fr(r, "parse tcode");
1.367 djm 3195: ssh_packet_disconnect(ssh, "Invalid extended_data message");
1.44 markus 3196: }
3197: if (c->efd == -1 ||
3198: c->extended_usage != CHAN_EXTENDED_WRITE ||
3199: tcode != SSH2_EXTENDED_DATA_STDERR) {
1.188 itojun 3200: logit("channel %d: bad ext data", c->self);
1.339 markus 3201: return 0;
1.44 markus 3202: }
1.389 djm 3203: if ((r = sshpkt_get_string_direct(ssh, &data, &data_len)) != 0 ||
3204: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3205: error_fr(r, "parse data");
1.367 djm 3206: ssh_packet_disconnect(ssh, "Invalid extended_data message");
3207: }
3208:
1.44 markus 3209: if (data_len > c->local_window) {
1.367 djm 3210: logit("channel %d: rcvd too much extended_data %zu, win %u",
1.44 markus 3211: c->self, data_len, c->local_window);
1.339 markus 3212: return 0;
1.44 markus 3213: }
1.367 djm 3214: debug2("channel %d: rcvd ext data %zu", c->self, data_len);
3215: /* XXX sshpkt_getb? */
3216: if ((r = sshbuf_put(c->extended, data, data_len)) != 0)
1.403 djm 3217: error_fr(r, "append");
1.44 markus 3218: c->local_window -= data_len;
1.339 markus 3219: return 0;
1.44 markus 3220: }
3221:
1.339 markus 3222: int
1.363 markus 3223: channel_input_ieof(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3224: {
1.367 djm 3225: Channel *c = channel_from_packet_id(ssh, __func__, "ieof");
1.389 djm 3226: int r;
1.367 djm 3227:
1.389 djm 3228: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3229: error_fr(r, "parse data");
1.389 djm 3230: ssh_packet_disconnect(ssh, "Invalid ieof message");
3231: }
1.41 markus 3232:
1.363 markus 3233: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3234: return 0;
1.367 djm 3235: chan_rcvd_ieof(ssh, c);
1.133 markus 3236:
3237: /* XXX force input close */
1.156 markus 3238: if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
1.133 markus 3239: debug("channel %d: FORCE input drain", c->self);
3240: c->istate = CHAN_INPUT_WAIT_DRAIN;
1.367 djm 3241: if (sshbuf_len(c->input) == 0)
3242: chan_ibuf_empty(ssh, c);
1.133 markus 3243: }
1.339 markus 3244: return 0;
1.41 markus 3245: }
1.1 deraadt 3246:
1.339 markus 3247: int
1.363 markus 3248: channel_input_oclose(int type, u_int32_t seq, struct ssh *ssh)
1.41 markus 3249: {
1.367 djm 3250: Channel *c = channel_from_packet_id(ssh, __func__, "oclose");
1.389 djm 3251: int r;
1.151 markus 3252:
1.363 markus 3253: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3254: return 0;
1.389 djm 3255: if ((r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3256: error_fr(r, "parse data");
1.389 djm 3257: ssh_packet_disconnect(ssh, "Invalid oclose message");
3258: }
1.367 djm 3259: chan_rcvd_oclose(ssh, c);
1.339 markus 3260: return 0;
1.1 deraadt 3261: }
3262:
1.339 markus 3263: int
1.363 markus 3264: channel_input_open_confirmation(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3265: {
1.367 djm 3266: Channel *c = channel_from_packet_id(ssh, __func__, "open confirmation");
3267: u_int32_t remote_window, remote_maxpacket;
3268: int r;
1.25 markus 3269:
1.363 markus 3270: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3271: return 0;
3272: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3273: ssh_packet_disconnect(ssh, "Received open confirmation for "
1.367 djm 3274: "non-opening channel %d.", c->self);
3275: /*
3276: * Record the remote channel number and mark that the channel
3277: * is now open.
3278: */
1.368 djm 3279: if ((r = sshpkt_get_u32(ssh, &c->remote_id)) != 0 ||
3280: (r = sshpkt_get_u32(ssh, &remote_window)) != 0 ||
1.389 djm 3281: (r = sshpkt_get_u32(ssh, &remote_maxpacket)) != 0 ||
3282: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3283: error_fr(r, "window/maxpacket");
1.389 djm 3284: ssh_packet_disconnect(ssh, "Invalid open confirmation message");
1.367 djm 3285: }
3286:
1.368 djm 3287: c->have_remote_id = 1;
1.367 djm 3288: c->remote_window = remote_window;
3289: c->remote_maxpacket = remote_maxpacket;
1.41 markus 3290: c->type = SSH_CHANNEL_OPEN;
1.358 djm 3291: if (c->open_confirm) {
1.403 djm 3292: debug2_f("channel %d: callback start", c->self);
1.367 djm 3293: c->open_confirm(ssh, c->self, 1, c->open_confirm_ctx);
1.403 djm 3294: debug2_f("channel %d: callback done", c->self);
1.44 markus 3295: }
1.358 djm 3296: debug2("channel %d: open confirm rwindow %u rmax %u", c->self,
3297: c->remote_window, c->remote_maxpacket);
1.339 markus 3298: return 0;
1.1 deraadt 3299: }
3300:
1.127 itojun 3301: static char *
1.114 markus 3302: reason2txt(int reason)
3303: {
1.143 deraadt 3304: switch (reason) {
1.114 markus 3305: case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
3306: return "administratively prohibited";
3307: case SSH2_OPEN_CONNECT_FAILED:
3308: return "connect failed";
3309: case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
3310: return "unknown channel type";
3311: case SSH2_OPEN_RESOURCE_SHORTAGE:
3312: return "resource shortage";
3313: }
1.117 stevesk 3314: return "unknown reason";
1.114 markus 3315: }
3316:
1.339 markus 3317: int
1.363 markus 3318: channel_input_open_failure(int type, u_int32_t seq, struct ssh *ssh)
1.1 deraadt 3319: {
1.367 djm 3320: Channel *c = channel_from_packet_id(ssh, __func__, "open failure");
3321: u_int32_t reason;
3322: char *msg = NULL;
3323: int r;
1.25 markus 3324:
1.363 markus 3325: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3326: return 0;
3327: if (c->type != SSH_CHANNEL_OPENING)
1.389 djm 3328: ssh_packet_disconnect(ssh, "Received open failure for "
1.367 djm 3329: "non-opening channel %d.", c->self);
3330: if ((r = sshpkt_get_u32(ssh, &reason)) != 0) {
1.403 djm 3331: error_fr(r, "parse reason");
1.389 djm 3332: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.367 djm 3333: }
1.378 djm 3334: /* skip language */
3335: if ((r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1.389 djm 3336: (r = sshpkt_get_string_direct(ssh, NULL, NULL)) != 0 ||
3337: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3338: error_fr(r, "parse msg/lang");
1.389 djm 3339: ssh_packet_disconnect(ssh, "Invalid open failure message");
1.358 djm 3340: }
1.367 djm 3341: logit("channel %d: open failed: %s%s%s", c->self,
1.358 djm 3342: reason2txt(reason), msg ? ": ": "", msg ? msg : "");
3343: free(msg);
3344: if (c->open_confirm) {
1.403 djm 3345: debug2_f("channel %d: callback start", c->self);
1.367 djm 3346: c->open_confirm(ssh, c->self, 0, c->open_confirm_ctx);
1.403 djm 3347: debug2_f("channel %d: callback done", c->self);
1.44 markus 3348: }
1.291 djm 3349: /* Schedule the channel for cleanup/deletion. */
1.367 djm 3350: chan_mark_dead(ssh, c);
1.339 markus 3351: return 0;
1.44 markus 3352: }
3353:
1.339 markus 3354: int
1.363 markus 3355: channel_input_window_adjust(int type, u_int32_t seq, struct ssh *ssh)
1.121 markus 3356: {
1.367 djm 3357: int id = channel_parse_id(ssh, __func__, "window adjust");
1.121 markus 3358: Channel *c;
1.367 djm 3359: u_int32_t adjust;
3360: u_int new_rwin;
3361: int r;
1.1 deraadt 3362:
1.367 djm 3363: if ((c = channel_lookup(ssh, id)) == NULL) {
1.229 markus 3364: logit("Received window adjust for non-open channel %d.", id);
1.339 markus 3365: return 0;
1.372 markus 3366: }
1.367 djm 3367:
1.363 markus 3368: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3369: return 0;
1.389 djm 3370: if ((r = sshpkt_get_u32(ssh, &adjust)) != 0 ||
3371: (r = sshpkt_get_end(ssh)) != 0) {
1.403 djm 3372: error_fr(r, "parse adjust");
1.389 djm 3373: ssh_packet_disconnect(ssh, "Invalid window adjust message");
1.367 djm 3374: }
3375: debug2("channel %d: rcvd adjust %u", c->self, adjust);
3376: if ((new_rwin = c->remote_window + adjust) < c->remote_window) {
1.346 djm 3377: fatal("channel %d: adjust %u overflows remote window %u",
1.367 djm 3378: c->self, adjust, c->remote_window);
3379: }
3380: c->remote_window = new_rwin;
1.339 markus 3381: return 0;
1.121 markus 3382: }
1.1 deraadt 3383:
1.339 markus 3384: int
1.363 markus 3385: channel_input_status_confirm(int type, u_int32_t seq, struct ssh *ssh)
1.275 djm 3386: {
1.367 djm 3387: int id = channel_parse_id(ssh, __func__, "status confirm");
1.275 djm 3388: Channel *c;
3389: struct channel_confirm *cc;
3390:
3391: /* Reset keepalive timeout */
1.389 djm 3392: ssh_packet_set_alive_timeouts(ssh, 0);
1.275 djm 3393:
1.403 djm 3394: debug2_f("type %d id %d", type, id);
1.275 djm 3395:
1.367 djm 3396: if ((c = channel_lookup(ssh, id)) == NULL) {
1.403 djm 3397: logit_f("%d: unknown", id);
1.339 markus 3398: return 0;
1.367 djm 3399: }
1.363 markus 3400: if (channel_proxy_upstream(c, type, seq, ssh))
1.354 markus 3401: return 0;
1.394 dtucker 3402: if (sshpkt_get_end(ssh) != 0)
1.389 djm 3403: ssh_packet_disconnect(ssh, "Invalid status confirm message");
1.275 djm 3404: if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL)
1.339 markus 3405: return 0;
1.367 djm 3406: cc->cb(ssh, type, c, cc->ctx);
1.275 djm 3407: TAILQ_REMOVE(&c->status_confirms, cc, entry);
1.396 jsg 3408: freezero(cc, sizeof(*cc));
1.339 markus 3409: return 0;
1.275 djm 3410: }
1.121 markus 3411:
3412: /* -- tcp forwarding */
1.135 markus 3413:
3414: void
1.367 djm 3415: channel_set_af(struct ssh *ssh, int af)
1.135 markus 3416: {
1.367 djm 3417: ssh->chanctxt->IPv4or6 = af;
1.135 markus 3418: }
1.121 markus 3419:
1.312 djm 3420:
3421: /*
3422: * Determine whether or not a port forward listens to loopback, the
3423: * specified address or wildcard. On the client, a specified bind
3424: * address will always override gateway_ports. On the server, a
3425: * gateway_ports of 1 (``yes'') will override the client's specification
3426: * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
3427: * will bind to whatever address the client asked for.
3428: *
3429: * Special-case listen_addrs are:
3430: *
3431: * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
3432: * "" (empty string), "*" -> wildcard v4/v6
3433: * "localhost" -> loopback v4/v6
1.334 djm 3434: * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
1.312 djm 3435: */
3436: static const char *
1.389 djm 3437: channel_fwd_bind_addr(struct ssh *ssh, const char *listen_addr, int *wildcardp,
1.336 millert 3438: int is_client, struct ForwardOptions *fwd_opts)
1.312 djm 3439: {
3440: const char *addr = NULL;
3441: int wildcard = 0;
3442:
3443: if (listen_addr == NULL) {
3444: /* No address specified: default to gateway_ports setting */
1.336 millert 3445: if (fwd_opts->gateway_ports)
1.312 djm 3446: wildcard = 1;
1.336 millert 3447: } else if (fwd_opts->gateway_ports || is_client) {
1.404 djm 3448: if (((ssh->compat & SSH_OLD_FORWARD_ADDR) &&
1.312 djm 3449: strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
3450: *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
1.336 millert 3451: (!is_client && fwd_opts->gateway_ports == 1)) {
1.312 djm 3452: wildcard = 1;
1.326 djm 3453: /*
3454: * Notify client if they requested a specific listen
3455: * address and it was overridden.
3456: */
3457: if (*listen_addr != '\0' &&
3458: strcmp(listen_addr, "0.0.0.0") != 0 &&
3459: strcmp(listen_addr, "*") != 0) {
1.389 djm 3460: ssh_packet_send_debug(ssh,
3461: "Forwarding listen address "
1.326 djm 3462: "\"%s\" overridden by server "
3463: "GatewayPorts", listen_addr);
3464: }
1.334 djm 3465: } else if (strcmp(listen_addr, "localhost") != 0 ||
3466: strcmp(listen_addr, "127.0.0.1") == 0 ||
3467: strcmp(listen_addr, "::1") == 0) {
1.395 djm 3468: /*
3469: * Accept explicit localhost address when
3470: * GatewayPorts=yes. The "localhost" hostname is
3471: * deliberately skipped here so it will listen on all
3472: * available local address families.
3473: */
1.334 djm 3474: addr = listen_addr;
1.326 djm 3475: }
1.334 djm 3476: } else if (strcmp(listen_addr, "127.0.0.1") == 0 ||
3477: strcmp(listen_addr, "::1") == 0) {
3478: /*
3479: * If a specific IPv4/IPv6 localhost address has been
3480: * requested then accept it even if gateway_ports is in
3481: * effect. This allows the client to prefer IPv4 or IPv6.
3482: */
3483: addr = listen_addr;
1.312 djm 3484: }
3485: if (wildcardp != NULL)
3486: *wildcardp = wildcard;
3487: return addr;
3488: }
3489:
1.160 markus 3490: static int
1.367 djm 3491: channel_setup_fwd_listener_tcpip(struct ssh *ssh, int type,
3492: struct Forward *fwd, int *allocated_listen_port,
3493: struct ForwardOptions *fwd_opts)
1.25 markus 3494: {
1.113 markus 3495: Channel *c;
1.226 djm 3496: int sock, r, success = 0, wildcard = 0, is_client;
1.35 markus 3497: struct addrinfo hints, *ai, *aitop;
1.212 djm 3498: const char *host, *addr;
1.35 markus 3499: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1.295 djm 3500: in_port_t *lport_p;
1.25 markus 3501:
1.212 djm 3502: is_client = (type == SSH_CHANNEL_PORT_LISTENER);
1.87 markus 3503:
1.344 millert 3504: if (is_client && fwd->connect_path != NULL) {
3505: host = fwd->connect_path;
3506: } else {
3507: host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
3508: fwd->listen_host : fwd->connect_host;
3509: if (host == NULL) {
3510: error("No forward host name.");
3511: return 0;
3512: }
3513: if (strlen(host) >= NI_MAXHOST) {
3514: error("Forward host name too long.");
3515: return 0;
3516: }
1.87 markus 3517: }
1.25 markus 3518:
1.312 djm 3519: /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
1.389 djm 3520: addr = channel_fwd_bind_addr(ssh, fwd->listen_host, &wildcard,
1.336 millert 3521: is_client, fwd_opts);
1.403 djm 3522: debug3_f("type %d wildcard %d addr %s", type, wildcard,
3523: (addr == NULL) ? "NULL" : addr);
1.212 djm 3524:
3525: /*
1.35 markus 3526: * getaddrinfo returns a loopback address if the hostname is
3527: * set to NULL and hints.ai_flags is not AI_PASSIVE
1.28 markus 3528: */
1.35 markus 3529: memset(&hints, 0, sizeof(hints));
1.367 djm 3530: hints.ai_family = ssh->chanctxt->IPv4or6;
1.212 djm 3531: hints.ai_flags = wildcard ? AI_PASSIVE : 0;
1.35 markus 3532: hints.ai_socktype = SOCK_STREAM;
1.336 millert 3533: snprintf(strport, sizeof strport, "%d", fwd->listen_port);
1.212 djm 3534: if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
3535: if (addr == NULL) {
3536: /* This really shouldn't happen */
1.389 djm 3537: ssh_packet_disconnect(ssh, "getaddrinfo: fatal error: %s",
1.271 dtucker 3538: ssh_gai_strerror(r));
1.212 djm 3539: } else {
1.403 djm 3540: error_f("getaddrinfo(%.64s): %s", addr,
1.271 dtucker 3541: ssh_gai_strerror(r));
1.212 djm 3542: }
1.218 markus 3543: return 0;
1.212 djm 3544: }
1.295 djm 3545: if (allocated_listen_port != NULL)
3546: *allocated_listen_port = 0;
1.35 markus 3547: for (ai = aitop; ai; ai = ai->ai_next) {
1.295 djm 3548: switch (ai->ai_family) {
3549: case AF_INET:
3550: lport_p = &((struct sockaddr_in *)ai->ai_addr)->
3551: sin_port;
3552: break;
3553: case AF_INET6:
3554: lport_p = &((struct sockaddr_in6 *)ai->ai_addr)->
3555: sin6_port;
3556: break;
3557: default:
1.35 markus 3558: continue;
1.295 djm 3559: }
3560: /*
3561: * If allocating a port for -R forwards, then use the
3562: * same port for all address families.
3563: */
1.367 djm 3564: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3565: fwd->listen_port == 0 && allocated_listen_port != NULL &&
3566: *allocated_listen_port > 0)
1.295 djm 3567: *lport_p = htons(*allocated_listen_port);
3568:
1.35 markus 3569: if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1.367 djm 3570: strport, sizeof(strport),
3571: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1.403 djm 3572: error_f("getnameinfo failed");
1.35 markus 3573: continue;
3574: }
3575: /* Create a port to listen for the host. */
1.300 dtucker 3576: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 3577: if (sock == -1) {
1.35 markus 3578: /* this is no error since kernel may not support ipv6 */
1.377 djm 3579: verbose("socket [%s]:%s: %.100s", ntop, strport,
3580: strerror(errno));
1.35 markus 3581: continue;
3582: }
1.226 djm 3583:
1.376 djm 3584: set_reuseaddr(sock);
1.182 stevesk 3585:
1.295 djm 3586: debug("Local forwarding listening on %s port %s.",
3587: ntop, strport);
1.35 markus 3588:
3589: /* Bind the socket to the address. */
1.393 deraadt 3590: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.367 djm 3591: /*
3592: * address can be in if use ipv6 address is
3593: * already bound
3594: */
1.377 djm 3595: verbose("bind [%s]:%s: %.100s",
3596: ntop, strport, strerror(errno));
1.35 markus 3597: close(sock);
3598: continue;
3599: }
3600: /* Start listening for connections on the socket. */
1.393 deraadt 3601: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.377 djm 3602: error("listen [%s]:%s: %.100s", ntop, strport,
3603: strerror(errno));
1.35 markus 3604: close(sock);
3605: continue;
3606: }
1.295 djm 3607:
3608: /*
1.336 millert 3609: * fwd->listen_port == 0 requests a dynamically allocated port -
1.295 djm 3610: * record what we got.
3611: */
1.367 djm 3612: if (type == SSH_CHANNEL_RPORT_LISTENER &&
3613: fwd->listen_port == 0 &&
1.295 djm 3614: allocated_listen_port != NULL &&
3615: *allocated_listen_port == 0) {
1.350 djm 3616: *allocated_listen_port = get_local_port(sock);
1.295 djm 3617: debug("Allocated listen port %d",
3618: *allocated_listen_port);
3619: }
3620:
1.35 markus 3621: /* Allocate a channel number for the socket. */
1.367 djm 3622: c = channel_new(ssh, "port listener", type, sock, sock, -1,
1.51 markus 3623: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1.190 markus 3624: 0, "port listener", 1);
1.293 djm 3625: c->path = xstrdup(host);
1.336 millert 3626: c->host_port = fwd->connect_port;
1.312 djm 3627: c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
1.336 millert 3628: if (fwd->listen_port == 0 && allocated_listen_port != NULL &&
1.404 djm 3629: !(ssh->compat & SSH_BUG_DYNAMIC_RPORT))
1.315 markus 3630: c->listening_port = *allocated_listen_port;
3631: else
1.336 millert 3632: c->listening_port = fwd->listen_port;
1.35 markus 3633: success = 1;
3634: }
3635: if (success == 0)
1.403 djm 3636: error_f("cannot listen to port: %d", fwd->listen_port);
1.35 markus 3637: freeaddrinfo(aitop);
1.87 markus 3638: return success;
1.25 markus 3639: }
1.1 deraadt 3640:
1.336 millert 3641: static int
1.367 djm 3642: channel_setup_fwd_listener_streamlocal(struct ssh *ssh, int type,
3643: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.336 millert 3644: {
3645: struct sockaddr_un sunaddr;
3646: const char *path;
3647: Channel *c;
3648: int port, sock;
3649: mode_t omask;
3650:
3651: switch (type) {
3652: case SSH_CHANNEL_UNIX_LISTENER:
3653: if (fwd->connect_path != NULL) {
3654: if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) {
3655: error("Local connecting path too long: %s",
3656: fwd->connect_path);
3657: return 0;
3658: }
3659: path = fwd->connect_path;
3660: port = PORT_STREAMLOCAL;
3661: } else {
3662: if (fwd->connect_host == NULL) {
3663: error("No forward host name.");
3664: return 0;
3665: }
3666: if (strlen(fwd->connect_host) >= NI_MAXHOST) {
3667: error("Forward host name too long.");
3668: return 0;
3669: }
3670: path = fwd->connect_host;
3671: port = fwd->connect_port;
3672: }
3673: break;
3674: case SSH_CHANNEL_RUNIX_LISTENER:
3675: path = fwd->listen_path;
3676: port = PORT_STREAMLOCAL;
3677: break;
3678: default:
1.403 djm 3679: error_f("unexpected channel type %d", type);
1.336 millert 3680: return 0;
3681: }
3682:
3683: if (fwd->listen_path == NULL) {
3684: error("No forward path name.");
3685: return 0;
3686: }
3687: if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) {
3688: error("Local listening path too long: %s", fwd->listen_path);
3689: return 0;
3690: }
3691:
1.403 djm 3692: debug3_f("type %d path %s", type, fwd->listen_path);
1.336 millert 3693:
3694: /* Start a Unix domain listener. */
3695: omask = umask(fwd_opts->streamlocal_bind_mask);
3696: sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG,
3697: fwd_opts->streamlocal_bind_unlink);
3698: umask(omask);
3699: if (sock < 0)
3700: return 0;
3701:
3702: debug("Local forwarding listening on path %s.", fwd->listen_path);
3703:
3704: /* Allocate a channel number for the socket. */
1.367 djm 3705: c = channel_new(ssh, "unix listener", type, sock, sock, -1,
1.336 millert 3706: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
3707: 0, "unix listener", 1);
3708: c->path = xstrdup(path);
3709: c->host_port = port;
3710: c->listening_port = PORT_STREAMLOCAL;
3711: c->listening_addr = xstrdup(fwd->listen_path);
3712: return 1;
3713: }
3714:
3715: static int
1.367 djm 3716: channel_cancel_rport_listener_tcpip(struct ssh *ssh,
3717: const char *host, u_short port)
1.202 djm 3718: {
1.209 avsm 3719: u_int i;
3720: int found = 0;
1.202 djm 3721:
1.367 djm 3722: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3723: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3724: if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER)
3725: continue;
3726: if (strcmp(c->path, host) == 0 && c->listening_port == port) {
1.403 djm 3727: debug2_f("close channel %d", i);
1.367 djm 3728: channel_free(ssh, c);
1.312 djm 3729: found = 1;
3730: }
3731: }
3732:
1.367 djm 3733: return found;
1.312 djm 3734: }
3735:
1.336 millert 3736: static int
1.367 djm 3737: channel_cancel_rport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3738: {
3739: u_int i;
3740: int found = 0;
3741:
1.367 djm 3742: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3743: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3744: if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER)
3745: continue;
3746: if (c->path == NULL)
3747: continue;
3748: if (strcmp(c->path, path) == 0) {
1.403 djm 3749: debug2_f("close channel %d", i);
1.367 djm 3750: channel_free(ssh, c);
1.336 millert 3751: found = 1;
3752: }
3753: }
3754:
1.367 djm 3755: return found;
1.336 millert 3756: }
3757:
1.312 djm 3758: int
1.367 djm 3759: channel_cancel_rport_listener(struct ssh *ssh, struct Forward *fwd)
1.336 millert 3760: {
1.367 djm 3761: if (fwd->listen_path != NULL) {
3762: return channel_cancel_rport_listener_streamlocal(ssh,
3763: fwd->listen_path);
3764: } else {
3765: return channel_cancel_rport_listener_tcpip(ssh,
3766: fwd->listen_host, fwd->listen_port);
3767: }
1.336 millert 3768: }
3769:
3770: static int
1.367 djm 3771: channel_cancel_lport_listener_tcpip(struct ssh *ssh,
3772: const char *lhost, u_short lport, int cport,
3773: struct ForwardOptions *fwd_opts)
1.312 djm 3774: {
3775: u_int i;
3776: int found = 0;
1.389 djm 3777: const char *addr = channel_fwd_bind_addr(ssh, lhost, NULL, 1, fwd_opts);
1.202 djm 3778:
1.367 djm 3779: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3780: Channel *c = ssh->chanctxt->channels[i];
1.312 djm 3781: if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER)
3782: continue;
1.313 markus 3783: if (c->listening_port != lport)
1.312 djm 3784: continue;
1.313 markus 3785: if (cport == CHANNEL_CANCEL_PORT_STATIC) {
3786: /* skip dynamic forwardings */
3787: if (c->host_port == 0)
3788: continue;
3789: } else {
3790: if (c->host_port != cport)
3791: continue;
3792: }
1.312 djm 3793: if ((c->listening_addr == NULL && addr != NULL) ||
3794: (c->listening_addr != NULL && addr == NULL))
3795: continue;
3796: if (addr == NULL || strcmp(c->listening_addr, addr) == 0) {
1.403 djm 3797: debug2_f("close channel %d", i);
1.367 djm 3798: channel_free(ssh, c);
1.202 djm 3799: found = 1;
3800: }
3801: }
3802:
1.367 djm 3803: return found;
1.202 djm 3804: }
3805:
1.336 millert 3806: static int
1.367 djm 3807: channel_cancel_lport_listener_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 3808: {
3809: u_int i;
3810: int found = 0;
3811:
3812: if (path == NULL) {
1.403 djm 3813: error_f("no path specified.");
1.336 millert 3814: return 0;
3815: }
3816:
1.367 djm 3817: for (i = 0; i < ssh->chanctxt->channels_alloc; i++) {
3818: Channel *c = ssh->chanctxt->channels[i];
1.336 millert 3819: if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER)
3820: continue;
3821: if (c->listening_addr == NULL)
3822: continue;
3823: if (strcmp(c->listening_addr, path) == 0) {
1.403 djm 3824: debug2_f("close channel %d", i);
1.367 djm 3825: channel_free(ssh, c);
1.336 millert 3826: found = 1;
3827: }
3828: }
3829:
1.367 djm 3830: return found;
1.336 millert 3831: }
3832:
3833: int
1.367 djm 3834: channel_cancel_lport_listener(struct ssh *ssh,
3835: struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts)
1.336 millert 3836: {
1.367 djm 3837: if (fwd->listen_path != NULL) {
3838: return channel_cancel_lport_listener_streamlocal(ssh,
3839: fwd->listen_path);
3840: } else {
3841: return channel_cancel_lport_listener_tcpip(ssh,
3842: fwd->listen_host, fwd->listen_port, cport, fwd_opts);
3843: }
1.336 millert 3844: }
3845:
1.362 markus 3846: /* protocol local port fwd, used by ssh */
1.160 markus 3847: int
1.367 djm 3848: channel_setup_local_fwd_listener(struct ssh *ssh,
3849: struct Forward *fwd, struct ForwardOptions *fwd_opts)
1.160 markus 3850: {
1.336 millert 3851: if (fwd->listen_path != NULL) {
1.367 djm 3852: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3853: SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts);
3854: } else {
1.367 djm 3855: return channel_setup_fwd_listener_tcpip(ssh,
3856: SSH_CHANNEL_PORT_LISTENER, fwd, NULL, fwd_opts);
1.336 millert 3857: }
1.160 markus 3858: }
3859:
1.381 djm 3860: /* Matches a remote forwarding permission against a requested forwarding */
3861: static int
3862: remote_open_match(struct permission *allowed_open, struct Forward *fwd)
3863: {
3864: int ret;
3865: char *lhost;
3866:
3867: /* XXX add ACLs for streamlocal */
3868: if (fwd->listen_path != NULL)
3869: return 1;
3870:
3871: if (fwd->listen_host == NULL || allowed_open->listen_host == NULL)
3872: return 0;
3873:
3874: if (allowed_open->listen_port != FWD_PERMIT_ANY_PORT &&
3875: allowed_open->listen_port != fwd->listen_port)
3876: return 0;
3877:
3878: /* Match hostnames case-insensitively */
3879: lhost = xstrdup(fwd->listen_host);
3880: lowercase(lhost);
3881: ret = match_pattern(lhost, allowed_open->listen_host);
3882: free(lhost);
3883:
3884: return ret;
3885: }
3886:
3887: /* Checks whether a requested remote forwarding is permitted */
3888: static int
3889: check_rfwd_permission(struct ssh *ssh, struct Forward *fwd)
3890: {
3891: struct ssh_channels *sc = ssh->chanctxt;
3892: struct permission_set *pset = &sc->remote_perms;
3893: u_int i, permit, permit_adm = 1;
3894: struct permission *perm;
3895:
3896: /* XXX apply GatewayPorts override before checking? */
3897:
3898: permit = pset->all_permitted;
3899: if (!permit) {
3900: for (i = 0; i < pset->num_permitted_user; i++) {
3901: perm = &pset->permitted_user[i];
3902: if (remote_open_match(perm, fwd)) {
3903: permit = 1;
3904: break;
3905: }
3906: }
3907: }
3908:
3909: if (pset->num_permitted_admin > 0) {
3910: permit_adm = 0;
3911: for (i = 0; i < pset->num_permitted_admin; i++) {
3912: perm = &pset->permitted_admin[i];
3913: if (remote_open_match(perm, fwd)) {
3914: permit_adm = 1;
3915: break;
3916: }
3917: }
3918: }
3919:
3920: return permit && permit_adm;
3921: }
3922:
1.160 markus 3923: /* protocol v2 remote port fwd, used by sshd */
3924: int
1.367 djm 3925: channel_setup_remote_fwd_listener(struct ssh *ssh, struct Forward *fwd,
1.336 millert 3926: int *allocated_listen_port, struct ForwardOptions *fwd_opts)
1.160 markus 3927: {
1.381 djm 3928: if (!check_rfwd_permission(ssh, fwd)) {
1.389 djm 3929: ssh_packet_send_debug(ssh, "port forwarding refused");
1.391 florian 3930: if (fwd->listen_path != NULL)
3931: /* XXX always allowed, see remote_open_match() */
3932: logit("Received request from %.100s port %d to "
3933: "remote forward to path \"%.100s\", "
3934: "but the request was denied.",
3935: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3936: fwd->listen_path);
3937: else if(fwd->listen_host != NULL)
3938: logit("Received request from %.100s port %d to "
3939: "remote forward to host %.100s port %d, "
3940: "but the request was denied.",
3941: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
3942: fwd->listen_host, fwd->listen_port );
3943: else
3944: logit("Received request from %.100s port %d to remote "
3945: "forward, but the request was denied.",
3946: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.381 djm 3947: return 0;
3948: }
1.336 millert 3949: if (fwd->listen_path != NULL) {
1.367 djm 3950: return channel_setup_fwd_listener_streamlocal(ssh,
1.336 millert 3951: SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts);
3952: } else {
1.367 djm 3953: return channel_setup_fwd_listener_tcpip(ssh,
1.336 millert 3954: SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port,
3955: fwd_opts);
3956: }
1.160 markus 3957: }
3958:
1.27 markus 3959: /*
1.312 djm 3960: * Translate the requested rfwd listen host to something usable for
3961: * this server.
3962: */
3963: static const char *
3964: channel_rfwd_bind_host(const char *listen_host)
3965: {
3966: if (listen_host == NULL) {
1.378 djm 3967: return "localhost";
1.312 djm 3968: } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) {
1.378 djm 3969: return "";
1.312 djm 3970: } else
3971: return listen_host;
3972: }
3973:
3974: /*
1.27 markus 3975: * Initiate forwarding of connections to port "port" on remote host through
3976: * the secure channel to host:port from local side.
1.315 markus 3977: * Returns handle (index) for updating the dynamic listen port with
1.381 djm 3978: * channel_update_permission().
1.27 markus 3979: */
1.253 markus 3980: int
1.367 djm 3981: channel_request_remote_forwarding(struct ssh *ssh, struct Forward *fwd)
1.25 markus 3982: {
1.367 djm 3983: int r, success = 0, idx = -1;
3984: char *host_to_connect, *listen_host, *listen_path;
3985: int port_to_connect, listen_port;
1.73 markus 3986:
1.25 markus 3987: /* Send the forward request to the remote side. */
1.358 djm 3988: if (fwd->listen_path != NULL) {
1.367 djm 3989: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3990: (r = sshpkt_put_cstring(ssh,
3991: "streamlocal-forward@openssh.com")) != 0 ||
3992: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
3993: (r = sshpkt_put_cstring(ssh, fwd->listen_path)) != 0 ||
3994: (r = sshpkt_send(ssh)) != 0 ||
3995: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 3996: fatal_fr(r, "request streamlocal");
1.336 millert 3997: } else {
1.367 djm 3998: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
3999: (r = sshpkt_put_cstring(ssh, "tcpip-forward")) != 0 ||
4000: (r = sshpkt_put_u8(ssh, 1)) != 0 || /* want reply */
4001: (r = sshpkt_put_cstring(ssh,
4002: channel_rfwd_bind_host(fwd->listen_host))) != 0 ||
4003: (r = sshpkt_put_u32(ssh, fwd->listen_port)) != 0 ||
4004: (r = sshpkt_send(ssh)) != 0 ||
4005: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4006: fatal_fr(r, "request tcpip-forward");
1.73 markus 4007: }
1.358 djm 4008: /* Assume that server accepts the request */
4009: success = 1;
1.73 markus 4010: if (success) {
1.305 djm 4011: /* Record that connection to this host/port is permitted. */
1.367 djm 4012: host_to_connect = listen_host = listen_path = NULL;
4013: port_to_connect = listen_port = 0;
1.336 millert 4014: if (fwd->connect_path != NULL) {
1.367 djm 4015: host_to_connect = xstrdup(fwd->connect_path);
4016: port_to_connect = PORT_STREAMLOCAL;
1.336 millert 4017: } else {
1.367 djm 4018: host_to_connect = xstrdup(fwd->connect_host);
4019: port_to_connect = fwd->connect_port;
1.336 millert 4020: }
4021: if (fwd->listen_path != NULL) {
1.367 djm 4022: listen_path = xstrdup(fwd->listen_path);
4023: listen_port = PORT_STREAMLOCAL;
1.336 millert 4024: } else {
1.367 djm 4025: if (fwd->listen_host != NULL)
4026: listen_host = xstrdup(fwd->listen_host);
4027: listen_port = fwd->listen_port;
4028: }
1.381 djm 4029: idx = permission_set_add(ssh, FORWARD_USER, FORWARD_LOCAL,
1.367 djm 4030: host_to_connect, port_to_connect,
4031: listen_host, listen_path, listen_port, NULL);
1.44 markus 4032: }
1.367 djm 4033: return idx;
1.1 deraadt 4034: }
4035:
1.333 markus 4036: static int
1.381 djm 4037: open_match(struct permission *allowed_open, const char *requestedhost,
1.336 millert 4038: int requestedport)
1.333 markus 4039: {
4040: if (allowed_open->host_to_connect == NULL)
4041: return 0;
4042: if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT &&
4043: allowed_open->port_to_connect != requestedport)
4044: return 0;
1.351 dtucker 4045: if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 &&
4046: strcmp(allowed_open->host_to_connect, requestedhost) != 0)
1.333 markus 4047: return 0;
4048: return 1;
4049: }
4050:
4051: /*
1.336 millert 4052: * Note that in the listen host/port case
1.333 markus 4053: * we don't support FWD_PERMIT_ANY_PORT and
4054: * need to translate between the configured-host (listen_host)
4055: * and what we've sent to the remote server (channel_rfwd_bind_host)
4056: */
4057: static int
1.381 djm 4058: open_listen_match_tcpip(struct permission *allowed_open,
1.336 millert 4059: const char *requestedhost, u_short requestedport, int translate)
1.333 markus 4060: {
4061: const char *allowed_host;
4062:
4063: if (allowed_open->host_to_connect == NULL)
4064: return 0;
4065: if (allowed_open->listen_port != requestedport)
4066: return 0;
1.335 djm 4067: if (!translate && allowed_open->listen_host == NULL &&
4068: requestedhost == NULL)
4069: return 1;
1.333 markus 4070: allowed_host = translate ?
4071: channel_rfwd_bind_host(allowed_open->listen_host) :
4072: allowed_open->listen_host;
1.382 djm 4073: if (allowed_host == NULL || requestedhost == NULL ||
1.333 markus 4074: strcmp(allowed_host, requestedhost) != 0)
4075: return 0;
4076: return 1;
4077: }
4078:
1.336 millert 4079: static int
1.381 djm 4080: open_listen_match_streamlocal(struct permission *allowed_open,
1.336 millert 4081: const char *requestedpath)
4082: {
4083: if (allowed_open->host_to_connect == NULL)
4084: return 0;
4085: if (allowed_open->listen_port != PORT_STREAMLOCAL)
4086: return 0;
4087: if (allowed_open->listen_path == NULL ||
4088: strcmp(allowed_open->listen_path, requestedpath) != 0)
4089: return 0;
4090: return 1;
4091: }
4092:
1.27 markus 4093: /*
1.208 deraadt 4094: * Request cancellation of remote forwarding of connection host:port from
1.202 djm 4095: * local side.
4096: */
1.336 millert 4097: static int
1.367 djm 4098: channel_request_rforward_cancel_tcpip(struct ssh *ssh,
4099: const char *host, u_short port)
1.202 djm 4100: {
1.367 djm 4101: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4102: struct permission_set *pset = &sc->local_perms;
1.367 djm 4103: int r;
4104: u_int i;
1.397 markus 4105: struct permission *perm = NULL;
1.202 djm 4106:
1.381 djm 4107: for (i = 0; i < pset->num_permitted_user; i++) {
4108: perm = &pset->permitted_user[i];
4109: if (open_listen_match_tcpip(perm, host, port, 0))
1.202 djm 4110: break;
1.381 djm 4111: perm = NULL;
1.202 djm 4112: }
1.381 djm 4113: if (perm == NULL) {
1.403 djm 4114: debug_f("requested forward not found");
1.312 djm 4115: return -1;
1.202 djm 4116: }
1.367 djm 4117: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4118: (r = sshpkt_put_cstring(ssh, "cancel-tcpip-forward")) != 0 ||
4119: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4120: (r = sshpkt_put_cstring(ssh, channel_rfwd_bind_host(host))) != 0 ||
4121: (r = sshpkt_put_u32(ssh, port)) != 0 ||
4122: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4123: fatal_fr(r, "send cancel");
1.367 djm 4124:
1.381 djm 4125: fwd_perm_clear(perm); /* unregister */
1.336 millert 4126:
4127: return 0;
4128: }
4129:
4130: /*
4131: * Request cancellation of remote forwarding of Unix domain socket
4132: * path from local side.
4133: */
4134: static int
1.367 djm 4135: channel_request_rforward_cancel_streamlocal(struct ssh *ssh, const char *path)
1.336 millert 4136: {
1.367 djm 4137: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4138: struct permission_set *pset = &sc->local_perms;
1.367 djm 4139: int r;
4140: u_int i;
1.397 markus 4141: struct permission *perm = NULL;
1.336 millert 4142:
1.381 djm 4143: for (i = 0; i < pset->num_permitted_user; i++) {
4144: perm = &pset->permitted_user[i];
4145: if (open_listen_match_streamlocal(perm, path))
1.336 millert 4146: break;
1.381 djm 4147: perm = NULL;
1.336 millert 4148: }
1.381 djm 4149: if (perm == NULL) {
1.403 djm 4150: debug_f("requested forward not found");
1.336 millert 4151: return -1;
4152: }
1.367 djm 4153: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
4154: (r = sshpkt_put_cstring(ssh,
4155: "cancel-streamlocal-forward@openssh.com")) != 0 ||
4156: (r = sshpkt_put_u8(ssh, 0)) != 0 || /* want reply */
4157: (r = sshpkt_put_cstring(ssh, path)) != 0 ||
4158: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4159: fatal_fr(r, "send cancel");
1.367 djm 4160:
1.381 djm 4161: fwd_perm_clear(perm); /* unregister */
1.312 djm 4162:
4163: return 0;
1.202 djm 4164: }
4165:
4166: /*
1.336 millert 4167: * Request cancellation of remote forwarding of a connection from local side.
4168: */
4169: int
1.367 djm 4170: channel_request_rforward_cancel(struct ssh *ssh, struct Forward *fwd)
1.336 millert 4171: {
4172: if (fwd->listen_path != NULL) {
1.367 djm 4173: return channel_request_rforward_cancel_streamlocal(ssh,
4174: fwd->listen_path);
1.336 millert 4175: } else {
1.367 djm 4176: return channel_request_rforward_cancel_tcpip(ssh,
4177: fwd->listen_host,
4178: fwd->listen_port ? fwd->listen_port : fwd->allocated_port);
1.336 millert 4179: }
1.1 deraadt 4180: }
4181:
1.99 markus 4182: /*
1.381 djm 4183: * Permits opening to any host/port if permitted_user[] is empty. This is
1.99 markus 4184: * usually called by the server, because the user could connect to any port
4185: * anyway, and the server has no way to know but to trust the client anyway.
4186: */
4187: void
1.381 djm 4188: channel_permit_all(struct ssh *ssh, int where)
4189: {
4190: struct permission_set *pset = permission_set_get(ssh, where);
4191:
4192: if (pset->num_permitted_user == 0)
4193: pset->all_permitted = 1;
4194: }
4195:
4196: /*
4197: * Permit the specified host/port for forwarding.
4198: */
4199: void
4200: channel_add_permission(struct ssh *ssh, int who, int where,
4201: char *host, int port)
4202: {
4203: int local = where == FORWARD_LOCAL;
4204: struct permission_set *pset = permission_set_get(ssh, where);
4205:
4206: debug("allow %s forwarding to host %s port %d",
4207: fwd_ident(who, where), host, port);
4208: /*
4209: * Remote forwards set listen_host/port, local forwards set
4210: * host/port_to_connect.
4211: */
4212: permission_set_add(ssh, who, where,
4213: local ? host : 0, local ? port : 0,
4214: local ? NULL : host, NULL, local ? 0 : port, NULL);
4215: pset->all_permitted = 0;
4216: }
4217:
4218: /*
4219: * Administratively disable forwarding.
4220: */
4221: void
4222: channel_disable_admin(struct ssh *ssh, int where)
1.99 markus 4223: {
1.381 djm 4224: channel_clear_permission(ssh, FORWARD_ADM, where);
4225: permission_set_add(ssh, FORWARD_ADM, where,
4226: NULL, 0, NULL, NULL, 0, NULL);
1.99 markus 4227: }
4228:
1.381 djm 4229: /*
4230: * Clear a list of permitted opens.
4231: */
1.101 markus 4232: void
1.381 djm 4233: channel_clear_permission(struct ssh *ssh, int who, int where)
1.99 markus 4234: {
1.381 djm 4235: struct permission **permp;
4236: u_int *npermp;
1.367 djm 4237:
1.381 djm 4238: permission_set_get_array(ssh, who, where, &permp, &npermp);
4239: *permp = xrecallocarray(*permp, *npermp, 0, sizeof(**permp));
4240: *npermp = 0;
1.315 markus 4241: }
4242:
4243: /*
4244: * Update the listen port for a dynamic remote forward, after
4245: * the actual 'newport' has been allocated. If 'newport' < 0 is
4246: * passed then they entry will be invalidated.
4247: */
4248: void
1.381 djm 4249: channel_update_permission(struct ssh *ssh, int idx, int newport)
1.315 markus 4250: {
1.381 djm 4251: struct permission_set *pset = &ssh->chanctxt->local_perms;
1.367 djm 4252:
1.381 djm 4253: if (idx < 0 || (u_int)idx >= pset->num_permitted_user) {
1.403 djm 4254: debug_f("index out of range: %d num_permitted_user %d",
4255: idx, pset->num_permitted_user);
1.315 markus 4256: return;
4257: }
4258: debug("%s allowed port %d for forwarding to host %s port %d",
4259: newport > 0 ? "Updating" : "Removing",
4260: newport,
1.381 djm 4261: pset->permitted_user[idx].host_to_connect,
4262: pset->permitted_user[idx].port_to_connect);
1.367 djm 4263: if (newport <= 0)
1.381 djm 4264: fwd_perm_clear(&pset->permitted_user[idx]);
1.367 djm 4265: else {
1.381 djm 4266: pset->permitted_user[idx].listen_port =
1.404 djm 4267: (ssh->compat & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport;
1.315 markus 4268: }
1.99 markus 4269: }
4270:
1.314 dtucker 4271: /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
4272: int
4273: permitopen_port(const char *p)
4274: {
4275: int port;
4276:
4277: if (strcmp(p, "*") == 0)
4278: return FWD_PERMIT_ANY_PORT;
4279: if ((port = a2port(p)) > 0)
4280: return port;
4281: return -1;
4282: }
4283:
1.276 djm 4284: /* Try to start non-blocking connect to next host in cctx list */
1.127 itojun 4285: static int
1.276 djm 4286: connect_next(struct channel_connect *cctx)
1.41 markus 4287: {
1.276 djm 4288: int sock, saved_errno;
1.336 millert 4289: struct sockaddr_un *sunaddr;
1.367 djm 4290: char ntop[NI_MAXHOST];
4291: char strport[MAXIMUM(NI_MAXSERV, sizeof(sunaddr->sun_path))];
1.41 markus 4292:
1.276 djm 4293: for (; cctx->ai; cctx->ai = cctx->ai->ai_next) {
1.336 millert 4294: switch (cctx->ai->ai_family) {
4295: case AF_UNIX:
4296: /* unix:pathname instead of host:port */
4297: sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr;
4298: strlcpy(ntop, "unix", sizeof(ntop));
4299: strlcpy(strport, sunaddr->sun_path, sizeof(strport));
4300: break;
4301: case AF_INET:
4302: case AF_INET6:
4303: if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen,
4304: ntop, sizeof(ntop), strport, sizeof(strport),
4305: NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
4306: error("connect_next: getnameinfo failed");
4307: continue;
4308: }
4309: break;
4310: default:
1.41 markus 4311: continue;
4312: }
1.300 dtucker 4313: if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype,
4314: cctx->ai->ai_protocol)) == -1) {
1.276 djm 4315: if (cctx->ai->ai_next == NULL)
1.186 djm 4316: error("socket: %.100s", strerror(errno));
4317: else
4318: verbose("socket: %.100s", strerror(errno));
1.41 markus 4319: continue;
4320: }
1.205 djm 4321: if (set_nonblock(sock) == -1)
1.403 djm 4322: fatal_f("set_nonblock(%d)", sock);
1.276 djm 4323: if (connect(sock, cctx->ai->ai_addr,
4324: cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) {
4325: debug("connect_next: host %.100s ([%.100s]:%s): "
4326: "%.100s", cctx->host, ntop, strport,
1.41 markus 4327: strerror(errno));
1.276 djm 4328: saved_errno = errno;
1.41 markus 4329: close(sock);
1.276 djm 4330: errno = saved_errno;
1.89 stevesk 4331: continue; /* fail -- try next */
1.41 markus 4332: }
1.336 millert 4333: if (cctx->ai->ai_family != AF_UNIX)
4334: set_nodelay(sock);
1.276 djm 4335: debug("connect_next: host %.100s ([%.100s]:%s) "
4336: "in progress, fd=%d", cctx->host, ntop, strport, sock);
4337: cctx->ai = cctx->ai->ai_next;
4338: return sock;
4339: }
4340: return -1;
4341: }
1.41 markus 4342:
1.276 djm 4343: static void
4344: channel_connect_ctx_free(struct channel_connect *cctx)
4345: {
1.321 djm 4346: free(cctx->host);
1.336 millert 4347: if (cctx->aitop) {
4348: if (cctx->aitop->ai_family == AF_UNIX)
4349: free(cctx->aitop);
4350: else
4351: freeaddrinfo(cctx->aitop);
4352: }
1.329 tedu 4353: memset(cctx, 0, sizeof(*cctx));
1.276 djm 4354: }
4355:
1.357 dtucker 4356: /*
1.372 markus 4357: * Return connecting socket to remote host:port or local socket path,
1.357 dtucker 4358: * passing back the failure reason if appropriate.
4359: */
1.372 markus 4360: static int
4361: connect_to_helper(struct ssh *ssh, const char *name, int port, int socktype,
4362: char *ctype, char *rname, struct channel_connect *cctx,
4363: int *reason, const char **errmsg)
1.276 djm 4364: {
4365: struct addrinfo hints;
4366: int gaierr;
4367: int sock = -1;
4368: char strport[NI_MAXSERV];
1.336 millert 4369:
4370: if (port == PORT_STREAMLOCAL) {
4371: struct sockaddr_un *sunaddr;
4372: struct addrinfo *ai;
4373:
4374: if (strlen(name) > sizeof(sunaddr->sun_path)) {
4375: error("%.100s: %.100s", name, strerror(ENAMETOOLONG));
1.372 markus 4376: return -1;
1.336 millert 4377: }
4378:
4379: /*
4380: * Fake up a struct addrinfo for AF_UNIX connections.
4381: * channel_connect_ctx_free() must check ai_family
4382: * and use free() not freeaddirinfo() for AF_UNIX.
4383: */
4384: ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr));
4385: memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr));
4386: ai->ai_addr = (struct sockaddr *)(ai + 1);
4387: ai->ai_addrlen = sizeof(*sunaddr);
4388: ai->ai_family = AF_UNIX;
1.372 markus 4389: ai->ai_socktype = socktype;
1.336 millert 4390: ai->ai_protocol = PF_UNSPEC;
4391: sunaddr = (struct sockaddr_un *)ai->ai_addr;
4392: sunaddr->sun_family = AF_UNIX;
4393: strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path));
1.372 markus 4394: cctx->aitop = ai;
1.336 millert 4395: } else {
4396: memset(&hints, 0, sizeof(hints));
1.367 djm 4397: hints.ai_family = ssh->chanctxt->IPv4or6;
1.372 markus 4398: hints.ai_socktype = socktype;
1.336 millert 4399: snprintf(strport, sizeof strport, "%d", port);
1.372 markus 4400: if ((gaierr = getaddrinfo(name, strport, &hints, &cctx->aitop))
1.357 dtucker 4401: != 0) {
4402: if (errmsg != NULL)
4403: *errmsg = ssh_gai_strerror(gaierr);
4404: if (reason != NULL)
4405: *reason = SSH2_OPEN_CONNECT_FAILED;
1.336 millert 4406: error("connect_to %.100s: unknown host (%s)", name,
4407: ssh_gai_strerror(gaierr));
1.372 markus 4408: return -1;
1.336 millert 4409: }
1.41 markus 4410: }
1.276 djm 4411:
1.372 markus 4412: cctx->host = xstrdup(name);
4413: cctx->port = port;
4414: cctx->ai = cctx->aitop;
1.276 djm 4415:
1.372 markus 4416: if ((sock = connect_next(cctx)) == -1) {
1.276 djm 4417: error("connect to %.100s port %d failed: %s",
1.336 millert 4418: name, port, strerror(errno));
1.372 markus 4419: return -1;
4420: }
4421:
4422: return sock;
4423: }
4424:
4425: /* Return CONNECTING channel to remote host:port or local socket path */
4426: static Channel *
4427: connect_to(struct ssh *ssh, const char *host, int port,
4428: char *ctype, char *rname)
4429: {
4430: struct channel_connect cctx;
4431: Channel *c;
4432: int sock;
4433:
4434: memset(&cctx, 0, sizeof(cctx));
4435: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4436: &cctx, NULL, NULL);
4437: if (sock == -1) {
1.276 djm 4438: channel_connect_ctx_free(&cctx);
4439: return NULL;
1.41 markus 4440: }
1.367 djm 4441: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
1.276 djm 4442: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
1.372 markus 4443: c->host_port = port;
4444: c->path = xstrdup(host);
1.276 djm 4445: c->connect_ctx = cctx;
1.372 markus 4446:
1.276 djm 4447: return c;
1.41 markus 4448: }
1.99 markus 4449:
1.354 markus 4450: /*
4451: * returns either the newly connected channel or the downstream channel
4452: * that needs to deal with this connection.
4453: */
1.276 djm 4454: Channel *
1.367 djm 4455: channel_connect_by_listen_address(struct ssh *ssh, const char *listen_host,
1.333 markus 4456: u_short listen_port, char *ctype, char *rname)
1.73 markus 4457: {
1.367 djm 4458: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4459: struct permission_set *pset = &sc->local_perms;
1.367 djm 4460: u_int i;
1.381 djm 4461: struct permission *perm;
1.99 markus 4462:
1.381 djm 4463: for (i = 0; i < pset->num_permitted_user; i++) {
4464: perm = &pset->permitted_user[i];
4465: if (open_listen_match_tcpip(perm,
4466: listen_host, listen_port, 1)) {
4467: if (perm->downstream)
4468: return perm->downstream;
4469: if (perm->port_to_connect == 0)
1.372 markus 4470: return rdynamic_connect_prepare(ssh,
4471: ctype, rname);
1.367 djm 4472: return connect_to(ssh,
1.381 djm 4473: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4474: ctype, rname);
1.276 djm 4475: }
4476: }
1.74 markus 4477: error("WARNING: Server requests forwarding for unknown listen_port %d",
4478: listen_port);
1.276 djm 4479: return NULL;
1.73 markus 4480: }
4481:
1.336 millert 4482: Channel *
1.367 djm 4483: channel_connect_by_listen_path(struct ssh *ssh, const char *path,
4484: char *ctype, char *rname)
1.336 millert 4485: {
1.367 djm 4486: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4487: struct permission_set *pset = &sc->local_perms;
1.367 djm 4488: u_int i;
1.381 djm 4489: struct permission *perm;
1.336 millert 4490:
1.381 djm 4491: for (i = 0; i < pset->num_permitted_user; i++) {
4492: perm = &pset->permitted_user[i];
4493: if (open_listen_match_streamlocal(perm, path)) {
1.367 djm 4494: return connect_to(ssh,
1.381 djm 4495: perm->host_to_connect, perm->port_to_connect,
1.367 djm 4496: ctype, rname);
1.336 millert 4497: }
4498: }
4499: error("WARNING: Server requests forwarding for unknown path %.100s",
4500: path);
4501: return NULL;
4502: }
4503:
1.99 markus 4504: /* Check if connecting to that port is permitted and connect. */
1.276 djm 4505: Channel *
1.367 djm 4506: channel_connect_to_port(struct ssh *ssh, const char *host, u_short port,
4507: char *ctype, char *rname, int *reason, const char **errmsg)
1.99 markus 4508: {
1.367 djm 4509: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4510: struct permission_set *pset = &sc->local_perms;
1.372 markus 4511: struct channel_connect cctx;
4512: Channel *c;
1.367 djm 4513: u_int i, permit, permit_adm = 1;
1.372 markus 4514: int sock;
1.381 djm 4515: struct permission *perm;
1.99 markus 4516:
1.381 djm 4517: permit = pset->all_permitted;
1.99 markus 4518: if (!permit) {
1.381 djm 4519: for (i = 0; i < pset->num_permitted_user; i++) {
4520: perm = &pset->permitted_user[i];
4521: if (open_match(perm, host, port)) {
1.99 markus 4522: permit = 1;
1.333 markus 4523: break;
4524: }
1.367 djm 4525: }
1.257 dtucker 4526: }
1.99 markus 4527:
1.381 djm 4528: if (pset->num_permitted_admin > 0) {
1.257 dtucker 4529: permit_adm = 0;
1.381 djm 4530: for (i = 0; i < pset->num_permitted_admin; i++) {
4531: perm = &pset->permitted_admin[i];
4532: if (open_match(perm, host, port)) {
1.257 dtucker 4533: permit_adm = 1;
1.333 markus 4534: break;
4535: }
1.367 djm 4536: }
1.99 markus 4537: }
1.257 dtucker 4538:
4539: if (!permit || !permit_adm) {
1.391 florian 4540: logit("Received request from %.100s port %d to connect to "
4541: "host %.100s port %d, but the request was denied.",
4542: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), host, port);
1.357 dtucker 4543: if (reason != NULL)
4544: *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED;
1.276 djm 4545: return NULL;
1.99 markus 4546: }
1.372 markus 4547:
4548: memset(&cctx, 0, sizeof(cctx));
4549: sock = connect_to_helper(ssh, host, port, SOCK_STREAM, ctype, rname,
4550: &cctx, reason, errmsg);
4551: if (sock == -1) {
4552: channel_connect_ctx_free(&cctx);
4553: return NULL;
4554: }
4555:
4556: c = channel_new(ssh, ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1,
4557: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4558: c->host_port = port;
4559: c->path = xstrdup(host);
4560: c->connect_ctx = cctx;
4561:
4562: return c;
1.336 millert 4563: }
4564:
4565: /* Check if connecting to that path is permitted and connect. */
4566: Channel *
1.367 djm 4567: channel_connect_to_path(struct ssh *ssh, const char *path,
4568: char *ctype, char *rname)
1.336 millert 4569: {
1.367 djm 4570: struct ssh_channels *sc = ssh->chanctxt;
1.381 djm 4571: struct permission_set *pset = &sc->local_perms;
1.367 djm 4572: u_int i, permit, permit_adm = 1;
1.381 djm 4573: struct permission *perm;
1.336 millert 4574:
1.381 djm 4575: permit = pset->all_permitted;
1.336 millert 4576: if (!permit) {
1.381 djm 4577: for (i = 0; i < pset->num_permitted_user; i++) {
4578: perm = &pset->permitted_user[i];
4579: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4580: permit = 1;
4581: break;
4582: }
1.367 djm 4583: }
1.336 millert 4584: }
4585:
1.381 djm 4586: if (pset->num_permitted_admin > 0) {
1.336 millert 4587: permit_adm = 0;
1.381 djm 4588: for (i = 0; i < pset->num_permitted_admin; i++) {
4589: perm = &pset->permitted_admin[i];
4590: if (open_match(perm, path, PORT_STREAMLOCAL)) {
1.336 millert 4591: permit_adm = 1;
4592: break;
4593: }
1.367 djm 4594: }
1.336 millert 4595: }
4596:
4597: if (!permit || !permit_adm) {
4598: logit("Received request to connect to path %.100s, "
4599: "but the request was denied.", path);
4600: return NULL;
4601: }
1.367 djm 4602: return connect_to(ssh, path, PORT_STREAMLOCAL, ctype, rname);
1.204 djm 4603: }
4604:
4605: void
1.367 djm 4606: channel_send_window_changes(struct ssh *ssh)
1.204 djm 4607: {
1.367 djm 4608: struct ssh_channels *sc = ssh->chanctxt;
4609: struct winsize ws;
4610: int r;
1.209 avsm 4611: u_int i;
1.204 djm 4612:
1.367 djm 4613: for (i = 0; i < sc->channels_alloc; i++) {
4614: if (sc->channels[i] == NULL || !sc->channels[i]->client_tty ||
4615: sc->channels[i]->type != SSH_CHANNEL_OPEN)
1.204 djm 4616: continue;
1.393 deraadt 4617: if (ioctl(sc->channels[i]->rfd, TIOCGWINSZ, &ws) == -1)
1.204 djm 4618: continue;
1.367 djm 4619: channel_request_start(ssh, i, "window-change", 0);
4620: if ((r = sshpkt_put_u32(ssh, (u_int)ws.ws_col)) != 0 ||
4621: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_row)) != 0 ||
4622: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_xpixel)) != 0 ||
4623: (r = sshpkt_put_u32(ssh, (u_int)ws.ws_ypixel)) != 0 ||
4624: (r = sshpkt_send(ssh)) != 0)
1.403 djm 4625: fatal_fr(r, "channel %u; send window-change", i);
1.204 djm 4626: }
1.372 markus 4627: }
4628:
4629: /* Return RDYNAMIC_OPEN channel: channel allows SOCKS, but is not connected */
4630: static Channel *
4631: rdynamic_connect_prepare(struct ssh *ssh, char *ctype, char *rname)
4632: {
4633: Channel *c;
4634: int r;
4635:
4636: c = channel_new(ssh, ctype, SSH_CHANNEL_RDYNAMIC_OPEN, -1, -1, -1,
4637: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1);
4638: c->host_port = 0;
4639: c->path = NULL;
4640:
4641: /*
4642: * We need to open the channel before we have a FD,
4643: * so that we can get SOCKS header from peer.
4644: */
4645: if ((r = sshpkt_start(ssh, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION)) != 0 ||
4646: (r = sshpkt_put_u32(ssh, c->remote_id)) != 0 ||
4647: (r = sshpkt_put_u32(ssh, c->self)) != 0 ||
4648: (r = sshpkt_put_u32(ssh, c->local_window)) != 0 ||
1.403 djm 4649: (r = sshpkt_put_u32(ssh, c->local_maxpacket)) != 0)
4650: fatal_fr(r, "channel %i; confirm", c->self);
1.372 markus 4651: return c;
4652: }
4653:
4654: /* Return CONNECTING socket to remote host:port or local socket path */
4655: static int
4656: rdynamic_connect_finish(struct ssh *ssh, Channel *c)
4657: {
1.405 markus 4658: struct ssh_channels *sc = ssh->chanctxt;
4659: struct permission_set *pset = &sc->local_perms;
4660: struct permission *perm;
1.372 markus 4661: struct channel_connect cctx;
1.405 markus 4662: u_int i, permit_adm = 1;
1.372 markus 4663: int sock;
1.405 markus 4664:
4665: if (pset->num_permitted_admin > 0) {
4666: permit_adm = 0;
4667: for (i = 0; i < pset->num_permitted_admin; i++) {
4668: perm = &pset->permitted_admin[i];
4669: if (open_match(perm, c->path, c->host_port)) {
4670: permit_adm = 1;
4671: break;
4672: }
4673: }
4674: }
4675: if (!permit_adm) {
4676: debug_f("requested forward not permitted");
4677: return -1;
4678: }
1.372 markus 4679:
4680: memset(&cctx, 0, sizeof(cctx));
4681: sock = connect_to_helper(ssh, c->path, c->host_port, SOCK_STREAM, NULL,
4682: NULL, &cctx, NULL, NULL);
4683: if (sock == -1)
4684: channel_connect_ctx_free(&cctx);
4685: else {
4686: /* similar to SSH_CHANNEL_CONNECTING but we've already sent the open */
4687: c->type = SSH_CHANNEL_RDYNAMIC_FINISH;
4688: c->connect_ctx = cctx;
4689: channel_register_fds(ssh, c, sock, sock, -1, 0, 1, 0);
4690: }
4691: return sock;
1.99 markus 4692: }
4693:
1.121 markus 4694: /* -- X11 forwarding */
1.1 deraadt 4695:
1.27 markus 4696: /*
4697: * Creates an internet domain socket for listening for X11 connections.
1.176 deraadt 4698: * Returns 0 and a suitable display number for the DISPLAY variable
4699: * stored in display_numberp , or -1 if an error occurs.
1.27 markus 4700: */
1.141 stevesk 4701: int
1.367 djm 4702: x11_create_display_inet(struct ssh *ssh, int x11_display_offset,
4703: int x11_use_localhost, int single_connection,
4704: u_int *display_numberp, int **chanids)
1.1 deraadt 4705: {
1.149 markus 4706: Channel *nc = NULL;
1.31 markus 4707: int display_number, sock;
4708: u_short port;
1.35 markus 4709: struct addrinfo hints, *ai, *aitop;
4710: char strport[NI_MAXSERV];
4711: int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1.25 markus 4712:
1.224 markus 4713: if (chanids == NULL)
4714: return -1;
4715:
1.33 markus 4716: for (display_number = x11_display_offset;
1.148 deraadt 4717: display_number < MAX_DISPLAYS;
4718: display_number++) {
1.25 markus 4719: port = 6000 + display_number;
1.35 markus 4720: memset(&hints, 0, sizeof(hints));
1.367 djm 4721: hints.ai_family = ssh->chanctxt->IPv4or6;
1.163 stevesk 4722: hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
1.35 markus 4723: hints.ai_socktype = SOCK_STREAM;
4724: snprintf(strport, sizeof strport, "%d", port);
1.367 djm 4725: if ((gaierr = getaddrinfo(NULL, strport,
4726: &hints, &aitop)) != 0) {
1.271 dtucker 4727: error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr));
1.141 stevesk 4728: return -1;
1.25 markus 4729: }
1.35 markus 4730: for (ai = aitop; ai; ai = ai->ai_next) {
1.367 djm 4731: if (ai->ai_family != AF_INET &&
4732: ai->ai_family != AF_INET6)
1.35 markus 4733: continue;
1.300 dtucker 4734: sock = socket(ai->ai_family, ai->ai_socktype,
4735: ai->ai_protocol);
1.393 deraadt 4736: if (sock == -1) {
1.35 markus 4737: error("socket: %.100s", strerror(errno));
1.203 markus 4738: freeaddrinfo(aitop);
1.141 stevesk 4739: return -1;
1.35 markus 4740: }
1.376 djm 4741: set_reuseaddr(sock);
1.393 deraadt 4742: if (bind(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.403 djm 4743: debug2_f("bind port %d: %.100s", port,
4744: strerror(errno));
1.35 markus 4745: close(sock);
1.367 djm 4746: for (n = 0; n < num_socks; n++)
1.35 markus 4747: close(socks[n]);
4748: num_socks = 0;
4749: break;
4750: }
4751: socks[num_socks++] = sock;
4752: if (num_socks == NUM_SOCKS)
4753: break;
1.25 markus 4754: }
1.83 stevesk 4755: freeaddrinfo(aitop);
1.35 markus 4756: if (num_socks > 0)
4757: break;
1.25 markus 4758: }
4759: if (display_number >= MAX_DISPLAYS) {
4760: error("Failed to allocate internet-domain X11 display socket.");
1.141 stevesk 4761: return -1;
1.25 markus 4762: }
4763: /* Start listening for connections on the socket. */
1.35 markus 4764: for (n = 0; n < num_socks; n++) {
4765: sock = socks[n];
1.393 deraadt 4766: if (listen(sock, SSH_LISTEN_BACKLOG) == -1) {
1.35 markus 4767: error("listen: %.100s", strerror(errno));
4768: close(sock);
1.141 stevesk 4769: return -1;
1.35 markus 4770: }
1.25 markus 4771: }
1.35 markus 4772:
4773: /* Allocate a channel for each socket. */
1.242 djm 4774: *chanids = xcalloc(num_socks + 1, sizeof(**chanids));
1.35 markus 4775: for (n = 0; n < num_socks; n++) {
4776: sock = socks[n];
1.367 djm 4777: nc = channel_new(ssh, "x11 listener",
1.51 markus 4778: SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
4779: CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1.190 markus 4780: 0, "X11 inet listener", 1);
1.167 markus 4781: nc->single_connection = single_connection;
1.224 markus 4782: (*chanids)[n] = nc->self;
1.35 markus 4783: }
1.224 markus 4784: (*chanids)[n] = -1;
1.1 deraadt 4785:
1.141 stevesk 4786: /* Return the display number for the DISPLAY environment variable. */
1.176 deraadt 4787: *display_numberp = display_number;
1.367 djm 4788: return 0;
1.1 deraadt 4789: }
4790:
1.127 itojun 4791: static int
1.77 markus 4792: connect_local_xsocket(u_int dnr)
1.1 deraadt 4793: {
1.25 markus 4794: int sock;
4795: struct sockaddr_un addr;
4796:
1.147 stevesk 4797: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1.393 deraadt 4798: if (sock == -1)
1.147 stevesk 4799: error("socket: %.100s", strerror(errno));
4800: memset(&addr, 0, sizeof(addr));
4801: addr.sun_family = AF_UNIX;
4802: snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
1.239 deraadt 4803: if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0)
1.147 stevesk 4804: return sock;
4805: close(sock);
1.25 markus 4806: error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
4807: return -1;
1.1 deraadt 4808: }
4809:
1.51 markus 4810: int
1.367 djm 4811: x11_connect_display(struct ssh *ssh)
1.1 deraadt 4812: {
1.248 deraadt 4813: u_int display_number;
1.25 markus 4814: const char *display;
1.51 markus 4815: char buf[1024], *cp;
1.35 markus 4816: struct addrinfo hints, *ai, *aitop;
4817: char strport[NI_MAXSERV];
1.248 deraadt 4818: int gaierr, sock = 0;
1.25 markus 4819:
4820: /* Try to open a socket for the local X server. */
4821: display = getenv("DISPLAY");
4822: if (!display) {
4823: error("DISPLAY not set.");
1.51 markus 4824: return -1;
1.25 markus 4825: }
1.27 markus 4826: /*
4827: * Now we decode the value of the DISPLAY variable and make a
4828: * connection to the real X server.
4829: */
4830:
4831: /*
4832: * Check if it is a unix domain socket. Unix domain displays are in
4833: * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4834: */
1.25 markus 4835: if (strncmp(display, "unix:", 5) == 0 ||
4836: display[0] == ':') {
4837: /* Connect to the unix domain socket. */
1.367 djm 4838: if (sscanf(strrchr(display, ':') + 1, "%u",
4839: &display_number) != 1) {
4840: error("Could not parse display number from DISPLAY: "
4841: "%.100s", display);
1.51 markus 4842: return -1;
1.25 markus 4843: }
4844: /* Create a socket. */
4845: sock = connect_local_xsocket(display_number);
4846: if (sock < 0)
1.51 markus 4847: return -1;
1.25 markus 4848:
4849: /* OK, we now have a connection to the display. */
1.51 markus 4850: return sock;
1.25 markus 4851: }
1.27 markus 4852: /*
4853: * Connect to an inet socket. The DISPLAY value is supposedly
4854: * hostname:d[.s], where hostname may also be numeric IP address.
4855: */
1.145 stevesk 4856: strlcpy(buf, display, sizeof(buf));
1.25 markus 4857: cp = strchr(buf, ':');
4858: if (!cp) {
4859: error("Could not find ':' in DISPLAY: %.100s", display);
1.51 markus 4860: return -1;
1.25 markus 4861: }
4862: *cp = 0;
1.367 djm 4863: /*
4864: * buf now contains the host name. But first we parse the
4865: * display number.
4866: */
1.248 deraadt 4867: if (sscanf(cp + 1, "%u", &display_number) != 1) {
1.25 markus 4868: error("Could not parse display number from DISPLAY: %.100s",
1.148 deraadt 4869: display);
1.51 markus 4870: return -1;
1.25 markus 4871: }
1.35 markus 4872:
4873: /* Look up the host address */
4874: memset(&hints, 0, sizeof(hints));
1.367 djm 4875: hints.ai_family = ssh->chanctxt->IPv4or6;
1.35 markus 4876: hints.ai_socktype = SOCK_STREAM;
1.248 deraadt 4877: snprintf(strport, sizeof strport, "%u", 6000 + display_number);
1.35 markus 4878: if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
1.271 dtucker 4879: error("%.100s: unknown host. (%s)", buf,
4880: ssh_gai_strerror(gaierr));
1.51 markus 4881: return -1;
1.25 markus 4882: }
1.35 markus 4883: for (ai = aitop; ai; ai = ai->ai_next) {
4884: /* Create a socket. */
1.300 dtucker 4885: sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
1.393 deraadt 4886: if (sock == -1) {
1.194 markus 4887: debug2("socket: %.100s", strerror(errno));
1.41 markus 4888: continue;
4889: }
4890: /* Connect it to the display. */
1.393 deraadt 4891: if (connect(sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.248 deraadt 4892: debug2("connect %.100s port %u: %.100s", buf,
1.41 markus 4893: 6000 + display_number, strerror(errno));
4894: close(sock);
4895: continue;
4896: }
4897: /* Success */
4898: break;
1.35 markus 4899: }
4900: freeaddrinfo(aitop);
4901: if (!ai) {
1.367 djm 4902: error("connect %.100s port %u: %.100s", buf,
4903: 6000 + display_number, strerror(errno));
1.51 markus 4904: return -1;
1.25 markus 4905: }
1.162 stevesk 4906: set_nodelay(sock);
1.51 markus 4907: return sock;
4908: }
4909:
4910: /*
1.27 markus 4911: * Requests forwarding of X11 connections, generates fake authentication
4912: * data, and enables authentication spoofing.
1.121 markus 4913: * This should be called in the client only.
1.27 markus 4914: */
1.49 markus 4915: void
1.367 djm 4916: x11_request_forwarding_with_spoofing(struct ssh *ssh, int client_session_id,
4917: const char *disp, const char *proto, const char *data, int want_reply)
1.1 deraadt 4918: {
1.367 djm 4919: struct ssh_channels *sc = ssh->chanctxt;
1.77 markus 4920: u_int data_len = (u_int) strlen(data) / 2;
1.219 djm 4921: u_int i, value;
1.367 djm 4922: const char *cp;
1.25 markus 4923: char *new_data;
1.367 djm 4924: int r, screen_number;
1.25 markus 4925:
1.367 djm 4926: if (sc->x11_saved_display == NULL)
4927: sc->x11_saved_display = xstrdup(disp);
4928: else if (strcmp(disp, sc->x11_saved_display) != 0) {
1.219 djm 4929: error("x11_request_forwarding_with_spoofing: different "
4930: "$DISPLAY already forwarded");
4931: return;
4932: }
4933:
1.266 djm 4934: cp = strchr(disp, ':');
1.25 markus 4935: if (cp)
4936: cp = strchr(cp, '.');
4937: if (cp)
1.245 deraadt 4938: screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL);
1.25 markus 4939: else
4940: screen_number = 0;
4941:
1.367 djm 4942: if (sc->x11_saved_proto == NULL) {
1.219 djm 4943: /* Save protocol name. */
1.367 djm 4944: sc->x11_saved_proto = xstrdup(proto);
1.353 natano 4945:
4946: /* Extract real authentication data. */
1.367 djm 4947: sc->x11_saved_data = xmalloc(data_len);
1.219 djm 4948: for (i = 0; i < data_len; i++) {
1.403 djm 4949: if (sscanf(data + 2 * i, "%2x", &value) != 1) {
1.219 djm 4950: fatal("x11_request_forwarding: bad "
4951: "authentication data: %.100s", data);
1.403 djm 4952: }
1.367 djm 4953: sc->x11_saved_data[i] = value;
1.219 djm 4954: }
1.367 djm 4955: sc->x11_saved_data_len = data_len;
1.353 natano 4956:
4957: /* Generate fake data of the same length. */
1.367 djm 4958: sc->x11_fake_data = xmalloc(data_len);
4959: arc4random_buf(sc->x11_fake_data, data_len);
4960: sc->x11_fake_data_len = data_len;
1.25 markus 4961: }
4962:
4963: /* Convert the fake data into hex. */
1.367 djm 4964: new_data = tohex(sc->x11_fake_data, data_len);
1.25 markus 4965:
4966: /* Send the request packet. */
1.367 djm 4967: channel_request_start(ssh, client_session_id, "x11-req", want_reply);
4968: if ((r = sshpkt_put_u8(ssh, 0)) != 0 || /* bool: single connection */
4969: (r = sshpkt_put_cstring(ssh, proto)) != 0 ||
4970: (r = sshpkt_put_cstring(ssh, new_data)) != 0 ||
4971: (r = sshpkt_put_u32(ssh, screen_number)) != 0 ||
4972: (r = sshpkt_send(ssh)) != 0 ||
4973: (r = ssh_packet_write_wait(ssh)) != 0)
1.403 djm 4974: fatal_fr(r, "send x11-req");
1.321 djm 4975: free(new_data);
1.1 deraadt 4976: }
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