Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 1 | /* $OpenBSD: channels.c,v 1.357 2017/02/01 02:59:09 dtucker Exp $ */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2 | /* |
| 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. |
| 9 | * |
| 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 | * |
| 16 | * SSH2 support added by Markus Friedl. |
| 17 | * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. |
| 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. |
| 40 | */ |
| 41 | |
| 42 | #include "includes.h" |
| 43 | |
| 44 | #include <sys/types.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 45 | #include <sys/stat.h> |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 46 | #include <sys/ioctl.h> |
| 47 | #include <sys/un.h> |
| 48 | #include <sys/socket.h> |
| 49 | #ifdef HAVE_SYS_TIME_H |
| 50 | # include <sys/time.h> |
| 51 | #endif |
| 52 | |
| 53 | #include <netinet/in.h> |
| 54 | #include <arpa/inet.h> |
| 55 | |
| 56 | #include <errno.h> |
| 57 | #include <fcntl.h> |
| 58 | #include <netdb.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 59 | #ifdef HAVE_STDINT_H |
| 60 | #include <stdint.h> |
| 61 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 62 | #include <stdio.h> |
| 63 | #include <stdlib.h> |
| 64 | #include <string.h> |
| 65 | #include <termios.h> |
| 66 | #include <unistd.h> |
| 67 | #include <stdarg.h> |
| 68 | |
| 69 | #include "openbsd-compat/sys-queue.h" |
| 70 | #include "xmalloc.h" |
| 71 | #include "ssh.h" |
| 72 | #include "ssh1.h" |
| 73 | #include "ssh2.h" |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 74 | #include "ssherr.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 75 | #include "packet.h" |
| 76 | #include "log.h" |
| 77 | #include "misc.h" |
| 78 | #include "buffer.h" |
| 79 | #include "channels.h" |
| 80 | #include "compat.h" |
| 81 | #include "canohost.h" |
| 82 | #include "key.h" |
| 83 | #include "authfd.h" |
| 84 | #include "pathnames.h" |
| 85 | |
| 86 | /* -- channel core */ |
| 87 | |
| 88 | /* |
| 89 | * Pointer to an array containing all allocated channels. The array is |
| 90 | * dynamically extended as needed. |
| 91 | */ |
| 92 | static Channel **channels = NULL; |
| 93 | |
| 94 | /* |
| 95 | * Size of the channel array. All slots of the array must always be |
| 96 | * initialized (at least the type field); unused slots set to NULL |
| 97 | */ |
| 98 | static u_int channels_alloc = 0; |
| 99 | |
| 100 | /* |
| 101 | * Maximum file descriptor value used in any of the channels. This is |
| 102 | * updated in channel_new. |
| 103 | */ |
| 104 | static int channel_max_fd = 0; |
| 105 | |
| 106 | |
| 107 | /* -- tcp forwarding */ |
| 108 | |
| 109 | /* |
| 110 | * Data structure for storing which hosts are permitted for forward requests. |
| 111 | * The local sides of any remote forwards are stored in this array to prevent |
| 112 | * a corrupt remote server from accessing arbitrary TCP/IP ports on our local |
| 113 | * network (which might be behind a firewall). |
| 114 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 115 | /* XXX: streamlocal wants a path instead of host:port */ |
| 116 | /* Overload host_to_connect; we could just make this match Forward */ |
| 117 | /* XXX - can we use listen_host instead of listen_path? */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 118 | typedef struct { |
| 119 | char *host_to_connect; /* Connect to 'host'. */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 120 | int port_to_connect; /* Connect to 'port'. */ |
| 121 | char *listen_host; /* Remote side should listen address. */ |
| 122 | char *listen_path; /* Remote side should listen path. */ |
| 123 | int listen_port; /* Remote side should listen port. */ |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 124 | Channel *downstream; /* Downstream mux*/ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 125 | } ForwardPermission; |
| 126 | |
| 127 | /* List of all permitted host/port pairs to connect by the user. */ |
| 128 | static ForwardPermission *permitted_opens = NULL; |
| 129 | |
| 130 | /* List of all permitted host/port pairs to connect by the admin. */ |
| 131 | static ForwardPermission *permitted_adm_opens = NULL; |
| 132 | |
| 133 | /* Number of permitted host/port pairs in the array permitted by the user. */ |
| 134 | static int num_permitted_opens = 0; |
| 135 | |
| 136 | /* Number of permitted host/port pair in the array permitted by the admin. */ |
| 137 | static int num_adm_permitted_opens = 0; |
| 138 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 139 | /* special-case port number meaning allow any port */ |
| 140 | #define FWD_PERMIT_ANY_PORT 0 |
| 141 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 142 | /* special-case wildcard meaning allow any host */ |
| 143 | #define FWD_PERMIT_ANY_HOST "*" |
| 144 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 145 | /* |
| 146 | * If this is true, all opens are permitted. This is the case on the server |
| 147 | * on which we have to trust the client anyway, and the user could do |
| 148 | * anything after logging in anyway. |
| 149 | */ |
| 150 | static int all_opens_permitted = 0; |
| 151 | |
| 152 | |
| 153 | /* -- X11 forwarding */ |
| 154 | |
| 155 | /* Maximum number of fake X11 displays to try. */ |
| 156 | #define MAX_DISPLAYS 1000 |
| 157 | |
| 158 | /* Saved X11 local (client) display. */ |
| 159 | static char *x11_saved_display = NULL; |
| 160 | |
| 161 | /* Saved X11 authentication protocol name. */ |
| 162 | static char *x11_saved_proto = NULL; |
| 163 | |
| 164 | /* Saved X11 authentication data. This is the real data. */ |
| 165 | static char *x11_saved_data = NULL; |
| 166 | static u_int x11_saved_data_len = 0; |
| 167 | |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 168 | /* Deadline after which all X11 connections are refused */ |
| 169 | static u_int x11_refuse_time; |
| 170 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 171 | /* |
| 172 | * Fake X11 authentication data. This is what the server will be sending us; |
| 173 | * we should replace any occurrences of this by the real data. |
| 174 | */ |
| 175 | static u_char *x11_fake_data = NULL; |
| 176 | static u_int x11_fake_data_len; |
| 177 | |
| 178 | |
| 179 | /* -- agent forwarding */ |
| 180 | |
| 181 | #define NUM_SOCKS 10 |
| 182 | |
| 183 | /* AF_UNSPEC or AF_INET or AF_INET6 */ |
| 184 | static int IPv4or6 = AF_UNSPEC; |
| 185 | |
| 186 | /* helper */ |
| 187 | static void port_open_helper(Channel *c, char *rtype); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 188 | static const char *channel_rfwd_bind_host(const char *listen_host); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 189 | |
| 190 | /* non-blocking connect helpers */ |
| 191 | static int connect_next(struct channel_connect *); |
| 192 | static void channel_connect_ctx_free(struct channel_connect *); |
| 193 | |
| 194 | /* -- channel core */ |
| 195 | |
| 196 | Channel * |
| 197 | channel_by_id(int id) |
| 198 | { |
| 199 | Channel *c; |
| 200 | |
| 201 | if (id < 0 || (u_int)id >= channels_alloc) { |
| 202 | logit("channel_by_id: %d: bad id", id); |
| 203 | return NULL; |
| 204 | } |
| 205 | c = channels[id]; |
| 206 | if (c == NULL) { |
| 207 | logit("channel_by_id: %d: bad id: channel free", id); |
| 208 | return NULL; |
| 209 | } |
| 210 | return c; |
| 211 | } |
| 212 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 213 | Channel * |
| 214 | channel_by_remote_id(int remote_id) |
| 215 | { |
| 216 | Channel *c; |
| 217 | u_int i; |
| 218 | |
| 219 | for (i = 0; i < channels_alloc; i++) { |
| 220 | c = channels[i]; |
| 221 | if (c != NULL && c->remote_id == remote_id) |
| 222 | return c; |
| 223 | } |
| 224 | return NULL; |
| 225 | } |
| 226 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 227 | /* |
| 228 | * Returns the channel if it is allowed to receive protocol messages. |
| 229 | * Private channels, like listening sockets, may not receive messages. |
| 230 | */ |
| 231 | Channel * |
| 232 | channel_lookup(int id) |
| 233 | { |
| 234 | Channel *c; |
| 235 | |
| 236 | if ((c = channel_by_id(id)) == NULL) |
| 237 | return (NULL); |
| 238 | |
| 239 | switch (c->type) { |
| 240 | case SSH_CHANNEL_X11_OPEN: |
| 241 | case SSH_CHANNEL_LARVAL: |
| 242 | case SSH_CHANNEL_CONNECTING: |
| 243 | case SSH_CHANNEL_DYNAMIC: |
| 244 | case SSH_CHANNEL_OPENING: |
| 245 | case SSH_CHANNEL_OPEN: |
| 246 | case SSH_CHANNEL_INPUT_DRAINING: |
| 247 | case SSH_CHANNEL_OUTPUT_DRAINING: |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 248 | case SSH_CHANNEL_ABANDONED: |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 249 | case SSH_CHANNEL_MUX_PROXY: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 250 | return (c); |
| 251 | } |
| 252 | logit("Non-public channel %d, type %d.", id, c->type); |
| 253 | return (NULL); |
| 254 | } |
| 255 | |
| 256 | /* |
| 257 | * Register filedescriptors for a channel, used when allocating a channel or |
| 258 | * when the channel consumer/producer is ready, e.g. shell exec'd |
| 259 | */ |
| 260 | static void |
| 261 | channel_register_fds(Channel *c, int rfd, int wfd, int efd, |
| 262 | int extusage, int nonblock, int is_tty) |
| 263 | { |
| 264 | /* Update the maximum file descriptor value. */ |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 265 | channel_max_fd = MAXIMUM(channel_max_fd, rfd); |
| 266 | channel_max_fd = MAXIMUM(channel_max_fd, wfd); |
| 267 | channel_max_fd = MAXIMUM(channel_max_fd, efd); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 268 | |
| 269 | if (rfd != -1) |
| 270 | fcntl(rfd, F_SETFD, FD_CLOEXEC); |
| 271 | if (wfd != -1 && wfd != rfd) |
| 272 | fcntl(wfd, F_SETFD, FD_CLOEXEC); |
| 273 | if (efd != -1 && efd != rfd && efd != wfd) |
| 274 | fcntl(efd, F_SETFD, FD_CLOEXEC); |
| 275 | |
| 276 | c->rfd = rfd; |
| 277 | c->wfd = wfd; |
| 278 | c->sock = (rfd == wfd) ? rfd : -1; |
| 279 | c->efd = efd; |
| 280 | c->extended_usage = extusage; |
| 281 | |
| 282 | if ((c->isatty = is_tty) != 0) |
| 283 | debug2("channel %d: rfd %d isatty", c->self, c->rfd); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 284 | #ifdef _AIX |
| 285 | /* XXX: Later AIX versions can't push as much data to tty */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 286 | c->wfd_isatty = is_tty || isatty(c->wfd); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 287 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 288 | |
| 289 | /* enable nonblocking mode */ |
| 290 | if (nonblock) { |
| 291 | if (rfd != -1) |
| 292 | set_nonblock(rfd); |
| 293 | if (wfd != -1) |
| 294 | set_nonblock(wfd); |
| 295 | if (efd != -1) |
| 296 | set_nonblock(efd); |
| 297 | } |
| 298 | } |
| 299 | |
| 300 | /* |
| 301 | * Allocate a new channel object and set its type and socket. This will cause |
| 302 | * remote_name to be freed. |
| 303 | */ |
| 304 | Channel * |
| 305 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
| 306 | u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock) |
| 307 | { |
| 308 | int found; |
| 309 | u_int i; |
| 310 | Channel *c; |
| 311 | |
| 312 | /* Do initial allocation if this is the first call. */ |
| 313 | if (channels_alloc == 0) { |
| 314 | channels_alloc = 10; |
| 315 | channels = xcalloc(channels_alloc, sizeof(Channel *)); |
| 316 | for (i = 0; i < channels_alloc; i++) |
| 317 | channels[i] = NULL; |
| 318 | } |
| 319 | /* Try to find a free slot where to put the new channel. */ |
| 320 | for (found = -1, i = 0; i < channels_alloc; i++) |
| 321 | if (channels[i] == NULL) { |
| 322 | /* Found a free slot. */ |
| 323 | found = (int)i; |
| 324 | break; |
| 325 | } |
| 326 | if (found < 0) { |
| 327 | /* There are no free slots. Take last+1 slot and expand the array. */ |
| 328 | found = channels_alloc; |
| 329 | if (channels_alloc > 10000) |
| 330 | fatal("channel_new: internal error: channels_alloc %d " |
| 331 | "too big.", channels_alloc); |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 332 | channels = xreallocarray(channels, channels_alloc + 10, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 333 | sizeof(Channel *)); |
| 334 | channels_alloc += 10; |
| 335 | debug2("channel: expanding %d", channels_alloc); |
| 336 | for (i = found; i < channels_alloc; i++) |
| 337 | channels[i] = NULL; |
| 338 | } |
| 339 | /* Initialize and return new channel. */ |
| 340 | c = channels[found] = xcalloc(1, sizeof(Channel)); |
| 341 | buffer_init(&c->input); |
| 342 | buffer_init(&c->output); |
| 343 | buffer_init(&c->extended); |
| 344 | c->path = NULL; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 345 | c->listening_addr = NULL; |
| 346 | c->listening_port = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 347 | c->ostate = CHAN_OUTPUT_OPEN; |
| 348 | c->istate = CHAN_INPUT_OPEN; |
| 349 | c->flags = 0; |
| 350 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, 0); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 351 | c->notbefore = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 352 | c->self = found; |
| 353 | c->type = type; |
| 354 | c->ctype = ctype; |
| 355 | c->local_window = window; |
| 356 | c->local_window_max = window; |
| 357 | c->local_consumed = 0; |
| 358 | c->local_maxpacket = maxpack; |
| 359 | c->remote_id = -1; |
| 360 | c->remote_name = xstrdup(remote_name); |
| 361 | c->remote_window = 0; |
| 362 | c->remote_maxpacket = 0; |
| 363 | c->force_drain = 0; |
| 364 | c->single_connection = 0; |
| 365 | c->detach_user = NULL; |
| 366 | c->detach_close = 0; |
| 367 | c->open_confirm = NULL; |
| 368 | c->open_confirm_ctx = NULL; |
| 369 | c->input_filter = NULL; |
| 370 | c->output_filter = NULL; |
| 371 | c->filter_ctx = NULL; |
| 372 | c->filter_cleanup = NULL; |
| 373 | c->ctl_chan = -1; |
| 374 | c->mux_rcb = NULL; |
| 375 | c->mux_ctx = NULL; |
| 376 | c->mux_pause = 0; |
| 377 | c->delayed = 1; /* prevent call to channel_post handler */ |
| 378 | TAILQ_INIT(&c->status_confirms); |
| 379 | debug("channel %d: new [%s]", found, remote_name); |
| 380 | return c; |
| 381 | } |
| 382 | |
| 383 | static int |
| 384 | channel_find_maxfd(void) |
| 385 | { |
| 386 | u_int i; |
| 387 | int max = 0; |
| 388 | Channel *c; |
| 389 | |
| 390 | for (i = 0; i < channels_alloc; i++) { |
| 391 | c = channels[i]; |
| 392 | if (c != NULL) { |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 393 | max = MAXIMUM(max, c->rfd); |
| 394 | max = MAXIMUM(max, c->wfd); |
| 395 | max = MAXIMUM(max, c->efd); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 396 | } |
| 397 | } |
| 398 | return max; |
| 399 | } |
| 400 | |
| 401 | int |
| 402 | channel_close_fd(int *fdp) |
| 403 | { |
| 404 | int ret = 0, fd = *fdp; |
| 405 | |
| 406 | if (fd != -1) { |
| 407 | ret = close(fd); |
| 408 | *fdp = -1; |
| 409 | if (fd == channel_max_fd) |
| 410 | channel_max_fd = channel_find_maxfd(); |
| 411 | } |
| 412 | return ret; |
| 413 | } |
| 414 | |
| 415 | /* Close all channel fd/socket. */ |
| 416 | static void |
| 417 | channel_close_fds(Channel *c) |
| 418 | { |
| 419 | channel_close_fd(&c->sock); |
| 420 | channel_close_fd(&c->rfd); |
| 421 | channel_close_fd(&c->wfd); |
| 422 | channel_close_fd(&c->efd); |
| 423 | } |
| 424 | |
| 425 | /* Free the channel and close its fd/socket. */ |
| 426 | void |
| 427 | channel_free(Channel *c) |
| 428 | { |
| 429 | char *s; |
| 430 | u_int i, n; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 431 | Channel *other; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 432 | struct channel_confirm *cc; |
| 433 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 434 | for (n = 0, i = 0; i < channels_alloc; i++) { |
| 435 | if ((other = channels[i]) != NULL) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 436 | n++; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 437 | |
| 438 | /* detach from mux client and prepare for closing */ |
| 439 | if (c->type == SSH_CHANNEL_MUX_CLIENT && |
| 440 | other->type == SSH_CHANNEL_MUX_PROXY && |
| 441 | other->mux_ctx == c) { |
| 442 | other->mux_ctx = NULL; |
| 443 | other->type = SSH_CHANNEL_OPEN; |
| 444 | other->istate = CHAN_INPUT_CLOSED; |
| 445 | other->ostate = CHAN_OUTPUT_CLOSED; |
| 446 | } |
| 447 | } |
| 448 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 449 | debug("channel %d: free: %s, nchannels %u", c->self, |
| 450 | c->remote_name ? c->remote_name : "???", n); |
| 451 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 452 | /* XXX more MUX cleanup: remove remote forwardings */ |
| 453 | if (c->type == SSH_CHANNEL_MUX_CLIENT) { |
| 454 | for (i = 0; i < (u_int)num_permitted_opens; i++) { |
| 455 | if (permitted_opens[i].downstream != c) |
| 456 | continue; |
| 457 | /* cancel on the server, since mux client is gone */ |
| 458 | debug("channel %d: cleanup remote forward for %s:%u", |
| 459 | c->self, |
| 460 | permitted_opens[i].listen_host, |
| 461 | permitted_opens[i].listen_port); |
| 462 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
| 463 | packet_put_cstring("cancel-tcpip-forward"); |
| 464 | packet_put_char(0); |
| 465 | packet_put_cstring(channel_rfwd_bind_host( |
| 466 | permitted_opens[i].listen_host)); |
| 467 | packet_put_int(permitted_opens[i].listen_port); |
| 468 | packet_send(); |
| 469 | /* unregister */ |
| 470 | permitted_opens[i].listen_port = 0; |
| 471 | permitted_opens[i].port_to_connect = 0; |
| 472 | free(permitted_opens[i].host_to_connect); |
| 473 | permitted_opens[i].host_to_connect = NULL; |
| 474 | free(permitted_opens[i].listen_host); |
| 475 | permitted_opens[i].listen_host = NULL; |
| 476 | permitted_opens[i].listen_path = NULL; |
| 477 | permitted_opens[i].downstream = NULL; |
| 478 | } |
| 479 | } |
| 480 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 481 | s = channel_open_message(); |
| 482 | debug3("channel %d: status: %s", c->self, s); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 483 | free(s); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 484 | |
| 485 | if (c->sock != -1) |
| 486 | shutdown(c->sock, SHUT_RDWR); |
| 487 | channel_close_fds(c); |
| 488 | buffer_free(&c->input); |
| 489 | buffer_free(&c->output); |
| 490 | buffer_free(&c->extended); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 491 | free(c->remote_name); |
| 492 | c->remote_name = NULL; |
| 493 | free(c->path); |
| 494 | c->path = NULL; |
| 495 | free(c->listening_addr); |
| 496 | c->listening_addr = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 497 | while ((cc = TAILQ_FIRST(&c->status_confirms)) != NULL) { |
| 498 | if (cc->abandon_cb != NULL) |
| 499 | cc->abandon_cb(c, cc->ctx); |
| 500 | TAILQ_REMOVE(&c->status_confirms, cc, entry); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 501 | explicit_bzero(cc, sizeof(*cc)); |
| 502 | free(cc); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 503 | } |
| 504 | if (c->filter_cleanup != NULL && c->filter_ctx != NULL) |
| 505 | c->filter_cleanup(c->self, c->filter_ctx); |
| 506 | channels[c->self] = NULL; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 507 | free(c); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 508 | } |
| 509 | |
| 510 | void |
| 511 | channel_free_all(void) |
| 512 | { |
| 513 | u_int i; |
| 514 | |
| 515 | for (i = 0; i < channels_alloc; i++) |
| 516 | if (channels[i] != NULL) |
| 517 | channel_free(channels[i]); |
| 518 | } |
| 519 | |
| 520 | /* |
| 521 | * Closes the sockets/fds of all channels. This is used to close extra file |
| 522 | * descriptors after a fork. |
| 523 | */ |
| 524 | void |
| 525 | channel_close_all(void) |
| 526 | { |
| 527 | u_int i; |
| 528 | |
| 529 | for (i = 0; i < channels_alloc; i++) |
| 530 | if (channels[i] != NULL) |
| 531 | channel_close_fds(channels[i]); |
| 532 | } |
| 533 | |
| 534 | /* |
| 535 | * Stop listening to channels. |
| 536 | */ |
| 537 | void |
| 538 | channel_stop_listening(void) |
| 539 | { |
| 540 | u_int i; |
| 541 | Channel *c; |
| 542 | |
| 543 | for (i = 0; i < channels_alloc; i++) { |
| 544 | c = channels[i]; |
| 545 | if (c != NULL) { |
| 546 | switch (c->type) { |
| 547 | case SSH_CHANNEL_AUTH_SOCKET: |
| 548 | case SSH_CHANNEL_PORT_LISTENER: |
| 549 | case SSH_CHANNEL_RPORT_LISTENER: |
| 550 | case SSH_CHANNEL_X11_LISTENER: |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 551 | case SSH_CHANNEL_UNIX_LISTENER: |
| 552 | case SSH_CHANNEL_RUNIX_LISTENER: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 553 | channel_close_fd(&c->sock); |
| 554 | channel_free(c); |
| 555 | break; |
| 556 | } |
| 557 | } |
| 558 | } |
| 559 | } |
| 560 | |
| 561 | /* |
| 562 | * Returns true if no channel has too much buffered data, and false if one or |
| 563 | * more channel is overfull. |
| 564 | */ |
| 565 | int |
| 566 | channel_not_very_much_buffered_data(void) |
| 567 | { |
| 568 | u_int i; |
| 569 | Channel *c; |
| 570 | |
| 571 | for (i = 0; i < channels_alloc; i++) { |
| 572 | c = channels[i]; |
| 573 | if (c != NULL && c->type == SSH_CHANNEL_OPEN) { |
| 574 | #if 0 |
| 575 | if (!compat20 && |
| 576 | buffer_len(&c->input) > packet_get_maxsize()) { |
| 577 | debug2("channel %d: big input buffer %d", |
| 578 | c->self, buffer_len(&c->input)); |
| 579 | return 0; |
| 580 | } |
| 581 | #endif |
| 582 | if (buffer_len(&c->output) > packet_get_maxsize()) { |
| 583 | debug2("channel %d: big output buffer %u > %u", |
| 584 | c->self, buffer_len(&c->output), |
| 585 | packet_get_maxsize()); |
| 586 | return 0; |
| 587 | } |
| 588 | } |
| 589 | } |
| 590 | return 1; |
| 591 | } |
| 592 | |
| 593 | /* Returns true if any channel is still open. */ |
| 594 | int |
| 595 | channel_still_open(void) |
| 596 | { |
| 597 | u_int i; |
| 598 | Channel *c; |
| 599 | |
| 600 | for (i = 0; i < channels_alloc; i++) { |
| 601 | c = channels[i]; |
| 602 | if (c == NULL) |
| 603 | continue; |
| 604 | switch (c->type) { |
| 605 | case SSH_CHANNEL_X11_LISTENER: |
| 606 | case SSH_CHANNEL_PORT_LISTENER: |
| 607 | case SSH_CHANNEL_RPORT_LISTENER: |
| 608 | case SSH_CHANNEL_MUX_LISTENER: |
| 609 | case SSH_CHANNEL_CLOSED: |
| 610 | case SSH_CHANNEL_AUTH_SOCKET: |
| 611 | case SSH_CHANNEL_DYNAMIC: |
| 612 | case SSH_CHANNEL_CONNECTING: |
| 613 | case SSH_CHANNEL_ZOMBIE: |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 614 | case SSH_CHANNEL_ABANDONED: |
| 615 | case SSH_CHANNEL_UNIX_LISTENER: |
| 616 | case SSH_CHANNEL_RUNIX_LISTENER: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 617 | continue; |
| 618 | case SSH_CHANNEL_LARVAL: |
| 619 | if (!compat20) |
| 620 | fatal("cannot happen: SSH_CHANNEL_LARVAL"); |
| 621 | continue; |
| 622 | case SSH_CHANNEL_OPENING: |
| 623 | case SSH_CHANNEL_OPEN: |
| 624 | case SSH_CHANNEL_X11_OPEN: |
| 625 | case SSH_CHANNEL_MUX_CLIENT: |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 626 | case SSH_CHANNEL_MUX_PROXY: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 627 | return 1; |
| 628 | case SSH_CHANNEL_INPUT_DRAINING: |
| 629 | case SSH_CHANNEL_OUTPUT_DRAINING: |
| 630 | if (!compat13) |
| 631 | fatal("cannot happen: OUT_DRAIN"); |
| 632 | return 1; |
| 633 | default: |
| 634 | fatal("channel_still_open: bad channel type %d", c->type); |
| 635 | /* NOTREACHED */ |
| 636 | } |
| 637 | } |
| 638 | return 0; |
| 639 | } |
| 640 | |
| 641 | /* Returns the id of an open channel suitable for keepaliving */ |
| 642 | int |
| 643 | channel_find_open(void) |
| 644 | { |
| 645 | u_int i; |
| 646 | Channel *c; |
| 647 | |
| 648 | for (i = 0; i < channels_alloc; i++) { |
| 649 | c = channels[i]; |
| 650 | if (c == NULL || c->remote_id < 0) |
| 651 | continue; |
| 652 | switch (c->type) { |
| 653 | case SSH_CHANNEL_CLOSED: |
| 654 | case SSH_CHANNEL_DYNAMIC: |
| 655 | case SSH_CHANNEL_X11_LISTENER: |
| 656 | case SSH_CHANNEL_PORT_LISTENER: |
| 657 | case SSH_CHANNEL_RPORT_LISTENER: |
| 658 | case SSH_CHANNEL_MUX_LISTENER: |
| 659 | case SSH_CHANNEL_MUX_CLIENT: |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 660 | case SSH_CHANNEL_MUX_PROXY: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 661 | case SSH_CHANNEL_OPENING: |
| 662 | case SSH_CHANNEL_CONNECTING: |
| 663 | case SSH_CHANNEL_ZOMBIE: |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 664 | case SSH_CHANNEL_ABANDONED: |
| 665 | case SSH_CHANNEL_UNIX_LISTENER: |
| 666 | case SSH_CHANNEL_RUNIX_LISTENER: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 667 | continue; |
| 668 | case SSH_CHANNEL_LARVAL: |
| 669 | case SSH_CHANNEL_AUTH_SOCKET: |
| 670 | case SSH_CHANNEL_OPEN: |
| 671 | case SSH_CHANNEL_X11_OPEN: |
| 672 | return i; |
| 673 | case SSH_CHANNEL_INPUT_DRAINING: |
| 674 | case SSH_CHANNEL_OUTPUT_DRAINING: |
| 675 | if (!compat13) |
| 676 | fatal("cannot happen: OUT_DRAIN"); |
| 677 | return i; |
| 678 | default: |
| 679 | fatal("channel_find_open: bad channel type %d", c->type); |
| 680 | /* NOTREACHED */ |
| 681 | } |
| 682 | } |
| 683 | return -1; |
| 684 | } |
| 685 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 686 | /* |
| 687 | * Returns a message describing the currently open forwarded connections, |
| 688 | * suitable for sending to the client. The message contains crlf pairs for |
| 689 | * newlines. |
| 690 | */ |
| 691 | char * |
| 692 | channel_open_message(void) |
| 693 | { |
| 694 | Buffer buffer; |
| 695 | Channel *c; |
| 696 | char buf[1024], *cp; |
| 697 | u_int i; |
| 698 | |
| 699 | buffer_init(&buffer); |
| 700 | snprintf(buf, sizeof buf, "The following connections are open:\r\n"); |
| 701 | buffer_append(&buffer, buf, strlen(buf)); |
| 702 | for (i = 0; i < channels_alloc; i++) { |
| 703 | c = channels[i]; |
| 704 | if (c == NULL) |
| 705 | continue; |
| 706 | switch (c->type) { |
| 707 | case SSH_CHANNEL_X11_LISTENER: |
| 708 | case SSH_CHANNEL_PORT_LISTENER: |
| 709 | case SSH_CHANNEL_RPORT_LISTENER: |
| 710 | case SSH_CHANNEL_CLOSED: |
| 711 | case SSH_CHANNEL_AUTH_SOCKET: |
| 712 | case SSH_CHANNEL_ZOMBIE: |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 713 | case SSH_CHANNEL_ABANDONED: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 714 | case SSH_CHANNEL_MUX_LISTENER: |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 715 | case SSH_CHANNEL_UNIX_LISTENER: |
| 716 | case SSH_CHANNEL_RUNIX_LISTENER: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 717 | continue; |
| 718 | case SSH_CHANNEL_LARVAL: |
| 719 | case SSH_CHANNEL_OPENING: |
| 720 | case SSH_CHANNEL_CONNECTING: |
| 721 | case SSH_CHANNEL_DYNAMIC: |
| 722 | case SSH_CHANNEL_OPEN: |
| 723 | case SSH_CHANNEL_X11_OPEN: |
| 724 | case SSH_CHANNEL_INPUT_DRAINING: |
| 725 | case SSH_CHANNEL_OUTPUT_DRAINING: |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 726 | case SSH_CHANNEL_MUX_PROXY: |
| 727 | case SSH_CHANNEL_MUX_CLIENT: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 728 | snprintf(buf, sizeof buf, |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 729 | " #%d %.300s (t%d r%d i%u/%d o%u/%d fd %d/%d cc %d)\r\n", |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 730 | c->self, c->remote_name, |
| 731 | c->type, c->remote_id, |
| 732 | c->istate, buffer_len(&c->input), |
| 733 | c->ostate, buffer_len(&c->output), |
| 734 | c->rfd, c->wfd, c->ctl_chan); |
| 735 | buffer_append(&buffer, buf, strlen(buf)); |
| 736 | continue; |
| 737 | default: |
| 738 | fatal("channel_open_message: bad channel type %d", c->type); |
| 739 | /* NOTREACHED */ |
| 740 | } |
| 741 | } |
| 742 | buffer_append(&buffer, "\0", 1); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 743 | cp = xstrdup((char *)buffer_ptr(&buffer)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 744 | buffer_free(&buffer); |
| 745 | return cp; |
| 746 | } |
| 747 | |
| 748 | void |
| 749 | channel_send_open(int id) |
| 750 | { |
| 751 | Channel *c = channel_lookup(id); |
| 752 | |
| 753 | if (c == NULL) { |
| 754 | logit("channel_send_open: %d: bad id", id); |
| 755 | return; |
| 756 | } |
| 757 | debug2("channel %d: send open", id); |
| 758 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
| 759 | packet_put_cstring(c->ctype); |
| 760 | packet_put_int(c->self); |
| 761 | packet_put_int(c->local_window); |
| 762 | packet_put_int(c->local_maxpacket); |
| 763 | packet_send(); |
| 764 | } |
| 765 | |
| 766 | void |
| 767 | channel_request_start(int id, char *service, int wantconfirm) |
| 768 | { |
| 769 | Channel *c = channel_lookup(id); |
| 770 | |
| 771 | if (c == NULL) { |
| 772 | logit("channel_request_start: %d: unknown channel id", id); |
| 773 | return; |
| 774 | } |
| 775 | debug2("channel %d: request %s confirm %d", id, service, wantconfirm); |
| 776 | packet_start(SSH2_MSG_CHANNEL_REQUEST); |
| 777 | packet_put_int(c->remote_id); |
| 778 | packet_put_cstring(service); |
| 779 | packet_put_char(wantconfirm); |
| 780 | } |
| 781 | |
| 782 | void |
| 783 | channel_register_status_confirm(int id, channel_confirm_cb *cb, |
| 784 | channel_confirm_abandon_cb *abandon_cb, void *ctx) |
| 785 | { |
| 786 | struct channel_confirm *cc; |
| 787 | Channel *c; |
| 788 | |
| 789 | if ((c = channel_lookup(id)) == NULL) |
| 790 | fatal("channel_register_expect: %d: bad id", id); |
| 791 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 792 | cc = xcalloc(1, sizeof(*cc)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 793 | cc->cb = cb; |
| 794 | cc->abandon_cb = abandon_cb; |
| 795 | cc->ctx = ctx; |
| 796 | TAILQ_INSERT_TAIL(&c->status_confirms, cc, entry); |
| 797 | } |
| 798 | |
| 799 | void |
| 800 | channel_register_open_confirm(int id, channel_open_fn *fn, void *ctx) |
| 801 | { |
| 802 | Channel *c = channel_lookup(id); |
| 803 | |
| 804 | if (c == NULL) { |
| 805 | logit("channel_register_open_confirm: %d: bad id", id); |
| 806 | return; |
| 807 | } |
| 808 | c->open_confirm = fn; |
| 809 | c->open_confirm_ctx = ctx; |
| 810 | } |
| 811 | |
| 812 | void |
| 813 | channel_register_cleanup(int id, channel_callback_fn *fn, int do_close) |
| 814 | { |
| 815 | Channel *c = channel_by_id(id); |
| 816 | |
| 817 | if (c == NULL) { |
| 818 | logit("channel_register_cleanup: %d: bad id", id); |
| 819 | return; |
| 820 | } |
| 821 | c->detach_user = fn; |
| 822 | c->detach_close = do_close; |
| 823 | } |
| 824 | |
| 825 | void |
| 826 | channel_cancel_cleanup(int id) |
| 827 | { |
| 828 | Channel *c = channel_by_id(id); |
| 829 | |
| 830 | if (c == NULL) { |
| 831 | logit("channel_cancel_cleanup: %d: bad id", id); |
| 832 | return; |
| 833 | } |
| 834 | c->detach_user = NULL; |
| 835 | c->detach_close = 0; |
| 836 | } |
| 837 | |
| 838 | void |
| 839 | channel_register_filter(int id, channel_infilter_fn *ifn, |
| 840 | channel_outfilter_fn *ofn, channel_filter_cleanup_fn *cfn, void *ctx) |
| 841 | { |
| 842 | Channel *c = channel_lookup(id); |
| 843 | |
| 844 | if (c == NULL) { |
| 845 | logit("channel_register_filter: %d: bad id", id); |
| 846 | return; |
| 847 | } |
| 848 | c->input_filter = ifn; |
| 849 | c->output_filter = ofn; |
| 850 | c->filter_ctx = ctx; |
| 851 | c->filter_cleanup = cfn; |
| 852 | } |
| 853 | |
| 854 | void |
| 855 | channel_set_fds(int id, int rfd, int wfd, int efd, |
| 856 | int extusage, int nonblock, int is_tty, u_int window_max) |
| 857 | { |
| 858 | Channel *c = channel_lookup(id); |
| 859 | |
| 860 | if (c == NULL || c->type != SSH_CHANNEL_LARVAL) |
| 861 | fatal("channel_activate for non-larval channel %d.", id); |
| 862 | channel_register_fds(c, rfd, wfd, efd, extusage, nonblock, is_tty); |
| 863 | c->type = SSH_CHANNEL_OPEN; |
| 864 | c->local_window = c->local_window_max = window_max; |
| 865 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
| 866 | packet_put_int(c->remote_id); |
| 867 | packet_put_int(c->local_window); |
| 868 | packet_send(); |
| 869 | } |
| 870 | |
| 871 | /* |
| 872 | * 'channel_pre*' are called just before select() to add any bits relevant to |
| 873 | * channels in the select bitmasks. |
| 874 | */ |
| 875 | /* |
| 876 | * 'channel_post*': perform any appropriate operations for channels which |
| 877 | * have events pending. |
| 878 | */ |
| 879 | typedef void chan_fn(Channel *c, fd_set *readset, fd_set *writeset); |
| 880 | chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE]; |
| 881 | chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE]; |
| 882 | |
| 883 | /* ARGSUSED */ |
| 884 | static void |
| 885 | channel_pre_listener(Channel *c, fd_set *readset, fd_set *writeset) |
| 886 | { |
| 887 | FD_SET(c->sock, readset); |
| 888 | } |
| 889 | |
| 890 | /* ARGSUSED */ |
| 891 | static void |
| 892 | channel_pre_connecting(Channel *c, fd_set *readset, fd_set *writeset) |
| 893 | { |
| 894 | debug3("channel %d: waiting for connection", c->self); |
| 895 | FD_SET(c->sock, writeset); |
| 896 | } |
| 897 | |
| 898 | static void |
| 899 | channel_pre_open_13(Channel *c, fd_set *readset, fd_set *writeset) |
| 900 | { |
| 901 | if (buffer_len(&c->input) < packet_get_maxsize()) |
| 902 | FD_SET(c->sock, readset); |
| 903 | if (buffer_len(&c->output) > 0) |
| 904 | FD_SET(c->sock, writeset); |
| 905 | } |
| 906 | |
| 907 | static void |
| 908 | channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset) |
| 909 | { |
| 910 | u_int limit = compat20 ? c->remote_window : packet_get_maxsize(); |
| 911 | |
| 912 | if (c->istate == CHAN_INPUT_OPEN && |
| 913 | limit > 0 && |
| 914 | buffer_len(&c->input) < limit && |
| 915 | buffer_check_alloc(&c->input, CHAN_RBUF)) |
| 916 | FD_SET(c->rfd, readset); |
| 917 | if (c->ostate == CHAN_OUTPUT_OPEN || |
| 918 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { |
| 919 | if (buffer_len(&c->output) > 0) { |
| 920 | FD_SET(c->wfd, writeset); |
| 921 | } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { |
| 922 | if (CHANNEL_EFD_OUTPUT_ACTIVE(c)) |
| 923 | debug2("channel %d: obuf_empty delayed efd %d/(%d)", |
| 924 | c->self, c->efd, buffer_len(&c->extended)); |
| 925 | else |
| 926 | chan_obuf_empty(c); |
| 927 | } |
| 928 | } |
| 929 | /** XXX check close conditions, too */ |
| 930 | if (compat20 && c->efd != -1 && |
| 931 | !(c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED)) { |
| 932 | if (c->extended_usage == CHAN_EXTENDED_WRITE && |
| 933 | buffer_len(&c->extended) > 0) |
| 934 | FD_SET(c->efd, writeset); |
| 935 | else if (c->efd != -1 && !(c->flags & CHAN_EOF_SENT) && |
| 936 | (c->extended_usage == CHAN_EXTENDED_READ || |
| 937 | c->extended_usage == CHAN_EXTENDED_IGNORE) && |
| 938 | buffer_len(&c->extended) < c->remote_window) |
| 939 | FD_SET(c->efd, readset); |
| 940 | } |
| 941 | /* XXX: What about efd? races? */ |
| 942 | } |
| 943 | |
| 944 | /* ARGSUSED */ |
| 945 | static void |
| 946 | channel_pre_input_draining(Channel *c, fd_set *readset, fd_set *writeset) |
| 947 | { |
| 948 | if (buffer_len(&c->input) == 0) { |
| 949 | packet_start(SSH_MSG_CHANNEL_CLOSE); |
| 950 | packet_put_int(c->remote_id); |
| 951 | packet_send(); |
| 952 | c->type = SSH_CHANNEL_CLOSED; |
| 953 | debug2("channel %d: closing after input drain.", c->self); |
| 954 | } |
| 955 | } |
| 956 | |
| 957 | /* ARGSUSED */ |
| 958 | static void |
| 959 | channel_pre_output_draining(Channel *c, fd_set *readset, fd_set *writeset) |
| 960 | { |
| 961 | if (buffer_len(&c->output) == 0) |
| 962 | chan_mark_dead(c); |
| 963 | else |
| 964 | FD_SET(c->sock, writeset); |
| 965 | } |
| 966 | |
| 967 | /* |
| 968 | * This is a special state for X11 authentication spoofing. An opened X11 |
| 969 | * connection (when authentication spoofing is being done) remains in this |
| 970 | * state until the first packet has been completely read. The authentication |
| 971 | * data in that packet is then substituted by the real data if it matches the |
| 972 | * fake data, and the channel is put into normal mode. |
| 973 | * XXX All this happens at the client side. |
| 974 | * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok |
| 975 | */ |
| 976 | static int |
| 977 | x11_open_helper(Buffer *b) |
| 978 | { |
| 979 | u_char *ucp; |
| 980 | u_int proto_len, data_len; |
| 981 | |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 982 | /* Is this being called after the refusal deadline? */ |
| 983 | if (x11_refuse_time != 0 && (u_int)monotime() >= x11_refuse_time) { |
| 984 | verbose("Rejected X11 connection after ForwardX11Timeout " |
| 985 | "expired"); |
| 986 | return -1; |
| 987 | } |
| 988 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 989 | /* Check if the fixed size part of the packet is in buffer. */ |
| 990 | if (buffer_len(b) < 12) |
| 991 | return 0; |
| 992 | |
| 993 | /* Parse the lengths of variable-length fields. */ |
| 994 | ucp = buffer_ptr(b); |
| 995 | if (ucp[0] == 0x42) { /* Byte order MSB first. */ |
| 996 | proto_len = 256 * ucp[6] + ucp[7]; |
| 997 | data_len = 256 * ucp[8] + ucp[9]; |
| 998 | } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */ |
| 999 | proto_len = ucp[6] + 256 * ucp[7]; |
| 1000 | data_len = ucp[8] + 256 * ucp[9]; |
| 1001 | } else { |
| 1002 | debug2("Initial X11 packet contains bad byte order byte: 0x%x", |
| 1003 | ucp[0]); |
| 1004 | return -1; |
| 1005 | } |
| 1006 | |
| 1007 | /* Check if the whole packet is in buffer. */ |
| 1008 | if (buffer_len(b) < |
| 1009 | 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3)) |
| 1010 | return 0; |
| 1011 | |
| 1012 | /* Check if authentication protocol matches. */ |
| 1013 | if (proto_len != strlen(x11_saved_proto) || |
| 1014 | memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) { |
| 1015 | debug2("X11 connection uses different authentication protocol."); |
| 1016 | return -1; |
| 1017 | } |
| 1018 | /* Check if authentication data matches our fake data. */ |
| 1019 | if (data_len != x11_fake_data_len || |
| 1020 | timingsafe_bcmp(ucp + 12 + ((proto_len + 3) & ~3), |
| 1021 | x11_fake_data, x11_fake_data_len) != 0) { |
| 1022 | debug2("X11 auth data does not match fake data."); |
| 1023 | return -1; |
| 1024 | } |
| 1025 | /* Check fake data length */ |
| 1026 | if (x11_fake_data_len != x11_saved_data_len) { |
| 1027 | error("X11 fake_data_len %d != saved_data_len %d", |
| 1028 | x11_fake_data_len, x11_saved_data_len); |
| 1029 | return -1; |
| 1030 | } |
| 1031 | /* |
| 1032 | * Received authentication protocol and data match |
| 1033 | * our fake data. Substitute the fake data with real |
| 1034 | * data. |
| 1035 | */ |
| 1036 | memcpy(ucp + 12 + ((proto_len + 3) & ~3), |
| 1037 | x11_saved_data, x11_saved_data_len); |
| 1038 | return 1; |
| 1039 | } |
| 1040 | |
| 1041 | static void |
| 1042 | channel_pre_x11_open_13(Channel *c, fd_set *readset, fd_set *writeset) |
| 1043 | { |
| 1044 | int ret = x11_open_helper(&c->output); |
| 1045 | |
| 1046 | if (ret == 1) { |
| 1047 | /* Start normal processing for the channel. */ |
| 1048 | c->type = SSH_CHANNEL_OPEN; |
| 1049 | channel_pre_open_13(c, readset, writeset); |
| 1050 | } else if (ret == -1) { |
| 1051 | /* |
| 1052 | * We have received an X11 connection that has bad |
| 1053 | * authentication information. |
| 1054 | */ |
| 1055 | logit("X11 connection rejected because of wrong authentication."); |
| 1056 | buffer_clear(&c->input); |
| 1057 | buffer_clear(&c->output); |
| 1058 | channel_close_fd(&c->sock); |
| 1059 | c->sock = -1; |
| 1060 | c->type = SSH_CHANNEL_CLOSED; |
| 1061 | packet_start(SSH_MSG_CHANNEL_CLOSE); |
| 1062 | packet_put_int(c->remote_id); |
| 1063 | packet_send(); |
| 1064 | } |
| 1065 | } |
| 1066 | |
| 1067 | static void |
| 1068 | channel_pre_x11_open(Channel *c, fd_set *readset, fd_set *writeset) |
| 1069 | { |
| 1070 | int ret = x11_open_helper(&c->output); |
| 1071 | |
| 1072 | /* c->force_drain = 1; */ |
| 1073 | |
| 1074 | if (ret == 1) { |
| 1075 | c->type = SSH_CHANNEL_OPEN; |
| 1076 | channel_pre_open(c, readset, writeset); |
| 1077 | } else if (ret == -1) { |
| 1078 | logit("X11 connection rejected because of wrong authentication."); |
| 1079 | debug2("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate); |
| 1080 | chan_read_failed(c); |
| 1081 | buffer_clear(&c->input); |
| 1082 | chan_ibuf_empty(c); |
| 1083 | buffer_clear(&c->output); |
| 1084 | /* for proto v1, the peer will send an IEOF */ |
| 1085 | if (compat20) |
| 1086 | chan_write_failed(c); |
| 1087 | else |
| 1088 | c->type = SSH_CHANNEL_OPEN; |
| 1089 | debug2("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate); |
| 1090 | } |
| 1091 | } |
| 1092 | |
| 1093 | static void |
| 1094 | channel_pre_mux_client(Channel *c, fd_set *readset, fd_set *writeset) |
| 1095 | { |
| 1096 | if (c->istate == CHAN_INPUT_OPEN && !c->mux_pause && |
| 1097 | buffer_check_alloc(&c->input, CHAN_RBUF)) |
| 1098 | FD_SET(c->rfd, readset); |
| 1099 | if (c->istate == CHAN_INPUT_WAIT_DRAIN) { |
| 1100 | /* clear buffer immediately (discard any partial packet) */ |
| 1101 | buffer_clear(&c->input); |
| 1102 | chan_ibuf_empty(c); |
| 1103 | /* Start output drain. XXX just kill chan? */ |
| 1104 | chan_rcvd_oclose(c); |
| 1105 | } |
| 1106 | if (c->ostate == CHAN_OUTPUT_OPEN || |
| 1107 | c->ostate == CHAN_OUTPUT_WAIT_DRAIN) { |
| 1108 | if (buffer_len(&c->output) > 0) |
| 1109 | FD_SET(c->wfd, writeset); |
| 1110 | else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) |
| 1111 | chan_obuf_empty(c); |
| 1112 | } |
| 1113 | } |
| 1114 | |
| 1115 | /* try to decode a socks4 header */ |
| 1116 | /* ARGSUSED */ |
| 1117 | static int |
| 1118 | channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset) |
| 1119 | { |
| 1120 | char *p, *host; |
| 1121 | u_int len, have, i, found, need; |
| 1122 | char username[256]; |
| 1123 | struct { |
| 1124 | u_int8_t version; |
| 1125 | u_int8_t command; |
| 1126 | u_int16_t dest_port; |
| 1127 | struct in_addr dest_addr; |
| 1128 | } s4_req, s4_rsp; |
| 1129 | |
| 1130 | debug2("channel %d: decode socks4", c->self); |
| 1131 | |
| 1132 | have = buffer_len(&c->input); |
| 1133 | len = sizeof(s4_req); |
| 1134 | if (have < len) |
| 1135 | return 0; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1136 | p = (char *)buffer_ptr(&c->input); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1137 | |
| 1138 | need = 1; |
| 1139 | /* SOCKS4A uses an invalid IP address 0.0.0.x */ |
| 1140 | if (p[4] == 0 && p[5] == 0 && p[6] == 0 && p[7] != 0) { |
| 1141 | debug2("channel %d: socks4a request", c->self); |
| 1142 | /* ... and needs an extra string (the hostname) */ |
| 1143 | need = 2; |
| 1144 | } |
| 1145 | /* Check for terminating NUL on the string(s) */ |
| 1146 | for (found = 0, i = len; i < have; i++) { |
| 1147 | if (p[i] == '\0') { |
| 1148 | found++; |
| 1149 | if (found == need) |
| 1150 | break; |
| 1151 | } |
| 1152 | if (i > 1024) { |
| 1153 | /* the peer is probably sending garbage */ |
| 1154 | debug("channel %d: decode socks4: too long", |
| 1155 | c->self); |
| 1156 | return -1; |
| 1157 | } |
| 1158 | } |
| 1159 | if (found < need) |
| 1160 | return 0; |
| 1161 | buffer_get(&c->input, (char *)&s4_req.version, 1); |
| 1162 | buffer_get(&c->input, (char *)&s4_req.command, 1); |
| 1163 | buffer_get(&c->input, (char *)&s4_req.dest_port, 2); |
| 1164 | buffer_get(&c->input, (char *)&s4_req.dest_addr, 4); |
| 1165 | have = buffer_len(&c->input); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1166 | p = (char *)buffer_ptr(&c->input); |
| 1167 | if (memchr(p, '\0', have) == NULL) |
| 1168 | fatal("channel %d: decode socks4: user not nul terminated", |
| 1169 | c->self); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1170 | len = strlen(p); |
| 1171 | debug2("channel %d: decode socks4: user %s/%d", c->self, p, len); |
| 1172 | len++; /* trailing '\0' */ |
| 1173 | if (len > have) |
| 1174 | fatal("channel %d: decode socks4: len %d > have %d", |
| 1175 | c->self, len, have); |
| 1176 | strlcpy(username, p, sizeof(username)); |
| 1177 | buffer_consume(&c->input, len); |
| 1178 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1179 | free(c->path); |
| 1180 | c->path = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1181 | if (need == 1) { /* SOCKS4: one string */ |
| 1182 | host = inet_ntoa(s4_req.dest_addr); |
| 1183 | c->path = xstrdup(host); |
| 1184 | } else { /* SOCKS4A: two strings */ |
| 1185 | have = buffer_len(&c->input); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1186 | p = (char *)buffer_ptr(&c->input); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1187 | len = strlen(p); |
| 1188 | debug2("channel %d: decode socks4a: host %s/%d", |
| 1189 | c->self, p, len); |
| 1190 | len++; /* trailing '\0' */ |
| 1191 | if (len > have) |
| 1192 | fatal("channel %d: decode socks4a: len %d > have %d", |
| 1193 | c->self, len, have); |
| 1194 | if (len > NI_MAXHOST) { |
| 1195 | error("channel %d: hostname \"%.100s\" too long", |
| 1196 | c->self, p); |
| 1197 | return -1; |
| 1198 | } |
| 1199 | c->path = xstrdup(p); |
| 1200 | buffer_consume(&c->input, len); |
| 1201 | } |
| 1202 | c->host_port = ntohs(s4_req.dest_port); |
| 1203 | |
| 1204 | debug2("channel %d: dynamic request: socks4 host %s port %u command %u", |
| 1205 | c->self, c->path, c->host_port, s4_req.command); |
| 1206 | |
| 1207 | if (s4_req.command != 1) { |
| 1208 | debug("channel %d: cannot handle: %s cn %d", |
| 1209 | c->self, need == 1 ? "SOCKS4" : "SOCKS4A", s4_req.command); |
| 1210 | return -1; |
| 1211 | } |
| 1212 | s4_rsp.version = 0; /* vn: 0 for reply */ |
| 1213 | s4_rsp.command = 90; /* cd: req granted */ |
| 1214 | s4_rsp.dest_port = 0; /* ignored */ |
| 1215 | s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */ |
| 1216 | buffer_append(&c->output, &s4_rsp, sizeof(s4_rsp)); |
| 1217 | return 1; |
| 1218 | } |
| 1219 | |
| 1220 | /* try to decode a socks5 header */ |
| 1221 | #define SSH_SOCKS5_AUTHDONE 0x1000 |
| 1222 | #define SSH_SOCKS5_NOAUTH 0x00 |
| 1223 | #define SSH_SOCKS5_IPV4 0x01 |
| 1224 | #define SSH_SOCKS5_DOMAIN 0x03 |
| 1225 | #define SSH_SOCKS5_IPV6 0x04 |
| 1226 | #define SSH_SOCKS5_CONNECT 0x01 |
| 1227 | #define SSH_SOCKS5_SUCCESS 0x00 |
| 1228 | |
| 1229 | /* ARGSUSED */ |
| 1230 | static int |
| 1231 | channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset) |
| 1232 | { |
| 1233 | struct { |
| 1234 | u_int8_t version; |
| 1235 | u_int8_t command; |
| 1236 | u_int8_t reserved; |
| 1237 | u_int8_t atyp; |
| 1238 | } s5_req, s5_rsp; |
| 1239 | u_int16_t dest_port; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1240 | char dest_addr[255+1], ntop[INET6_ADDRSTRLEN]; |
| 1241 | u_char *p; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1242 | u_int have, need, i, found, nmethods, addrlen, af; |
| 1243 | |
| 1244 | debug2("channel %d: decode socks5", c->self); |
| 1245 | p = buffer_ptr(&c->input); |
| 1246 | if (p[0] != 0x05) |
| 1247 | return -1; |
| 1248 | have = buffer_len(&c->input); |
| 1249 | if (!(c->flags & SSH_SOCKS5_AUTHDONE)) { |
| 1250 | /* format: ver | nmethods | methods */ |
| 1251 | if (have < 2) |
| 1252 | return 0; |
| 1253 | nmethods = p[1]; |
| 1254 | if (have < nmethods + 2) |
| 1255 | return 0; |
| 1256 | /* look for method: "NO AUTHENTICATION REQUIRED" */ |
| 1257 | for (found = 0, i = 2; i < nmethods + 2; i++) { |
| 1258 | if (p[i] == SSH_SOCKS5_NOAUTH) { |
| 1259 | found = 1; |
| 1260 | break; |
| 1261 | } |
| 1262 | } |
| 1263 | if (!found) { |
| 1264 | debug("channel %d: method SSH_SOCKS5_NOAUTH not found", |
| 1265 | c->self); |
| 1266 | return -1; |
| 1267 | } |
| 1268 | buffer_consume(&c->input, nmethods + 2); |
| 1269 | buffer_put_char(&c->output, 0x05); /* version */ |
| 1270 | buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH); /* method */ |
| 1271 | FD_SET(c->sock, writeset); |
| 1272 | c->flags |= SSH_SOCKS5_AUTHDONE; |
| 1273 | debug2("channel %d: socks5 auth done", c->self); |
| 1274 | return 0; /* need more */ |
| 1275 | } |
| 1276 | debug2("channel %d: socks5 post auth", c->self); |
| 1277 | if (have < sizeof(s5_req)+1) |
| 1278 | return 0; /* need more */ |
| 1279 | memcpy(&s5_req, p, sizeof(s5_req)); |
| 1280 | if (s5_req.version != 0x05 || |
| 1281 | s5_req.command != SSH_SOCKS5_CONNECT || |
| 1282 | s5_req.reserved != 0x00) { |
| 1283 | debug2("channel %d: only socks5 connect supported", c->self); |
| 1284 | return -1; |
| 1285 | } |
| 1286 | switch (s5_req.atyp){ |
| 1287 | case SSH_SOCKS5_IPV4: |
| 1288 | addrlen = 4; |
| 1289 | af = AF_INET; |
| 1290 | break; |
| 1291 | case SSH_SOCKS5_DOMAIN: |
| 1292 | addrlen = p[sizeof(s5_req)]; |
| 1293 | af = -1; |
| 1294 | break; |
| 1295 | case SSH_SOCKS5_IPV6: |
| 1296 | addrlen = 16; |
| 1297 | af = AF_INET6; |
| 1298 | break; |
| 1299 | default: |
| 1300 | debug2("channel %d: bad socks5 atyp %d", c->self, s5_req.atyp); |
| 1301 | return -1; |
| 1302 | } |
| 1303 | need = sizeof(s5_req) + addrlen + 2; |
| 1304 | if (s5_req.atyp == SSH_SOCKS5_DOMAIN) |
| 1305 | need++; |
| 1306 | if (have < need) |
| 1307 | return 0; |
| 1308 | buffer_consume(&c->input, sizeof(s5_req)); |
| 1309 | if (s5_req.atyp == SSH_SOCKS5_DOMAIN) |
| 1310 | buffer_consume(&c->input, 1); /* host string length */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1311 | buffer_get(&c->input, &dest_addr, addrlen); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1312 | buffer_get(&c->input, (char *)&dest_port, 2); |
| 1313 | dest_addr[addrlen] = '\0'; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1314 | free(c->path); |
| 1315 | c->path = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1316 | if (s5_req.atyp == SSH_SOCKS5_DOMAIN) { |
| 1317 | if (addrlen >= NI_MAXHOST) { |
| 1318 | error("channel %d: dynamic request: socks5 hostname " |
| 1319 | "\"%.100s\" too long", c->self, dest_addr); |
| 1320 | return -1; |
| 1321 | } |
| 1322 | c->path = xstrdup(dest_addr); |
| 1323 | } else { |
| 1324 | if (inet_ntop(af, dest_addr, ntop, sizeof(ntop)) == NULL) |
| 1325 | return -1; |
| 1326 | c->path = xstrdup(ntop); |
| 1327 | } |
| 1328 | c->host_port = ntohs(dest_port); |
| 1329 | |
| 1330 | debug2("channel %d: dynamic request: socks5 host %s port %u command %u", |
| 1331 | c->self, c->path, c->host_port, s5_req.command); |
| 1332 | |
| 1333 | s5_rsp.version = 0x05; |
| 1334 | s5_rsp.command = SSH_SOCKS5_SUCCESS; |
| 1335 | s5_rsp.reserved = 0; /* ignored */ |
| 1336 | s5_rsp.atyp = SSH_SOCKS5_IPV4; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1337 | dest_port = 0; /* ignored */ |
| 1338 | |
| 1339 | buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp)); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1340 | buffer_put_int(&c->output, ntohl(INADDR_ANY)); /* bind address */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1341 | buffer_append(&c->output, &dest_port, sizeof(dest_port)); |
| 1342 | return 1; |
| 1343 | } |
| 1344 | |
| 1345 | Channel * |
| 1346 | channel_connect_stdio_fwd(const char *host_to_connect, u_short port_to_connect, |
| 1347 | int in, int out) |
| 1348 | { |
| 1349 | Channel *c; |
| 1350 | |
| 1351 | debug("channel_connect_stdio_fwd %s:%d", host_to_connect, |
| 1352 | port_to_connect); |
| 1353 | |
| 1354 | c = channel_new("stdio-forward", SSH_CHANNEL_OPENING, in, out, |
| 1355 | -1, CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
| 1356 | 0, "stdio-forward", /*nonblock*/0); |
| 1357 | |
| 1358 | c->path = xstrdup(host_to_connect); |
| 1359 | c->host_port = port_to_connect; |
| 1360 | c->listening_port = 0; |
| 1361 | c->force_drain = 1; |
| 1362 | |
| 1363 | channel_register_fds(c, in, out, -1, 0, 1, 0); |
| 1364 | port_open_helper(c, "direct-tcpip"); |
| 1365 | |
| 1366 | return c; |
| 1367 | } |
| 1368 | |
| 1369 | /* dynamic port forwarding */ |
| 1370 | static void |
| 1371 | channel_pre_dynamic(Channel *c, fd_set *readset, fd_set *writeset) |
| 1372 | { |
| 1373 | u_char *p; |
| 1374 | u_int have; |
| 1375 | int ret; |
| 1376 | |
| 1377 | have = buffer_len(&c->input); |
| 1378 | debug2("channel %d: pre_dynamic: have %d", c->self, have); |
| 1379 | /* buffer_dump(&c->input); */ |
| 1380 | /* check if the fixed size part of the packet is in buffer. */ |
| 1381 | if (have < 3) { |
| 1382 | /* need more */ |
| 1383 | FD_SET(c->sock, readset); |
| 1384 | return; |
| 1385 | } |
| 1386 | /* try to guess the protocol */ |
| 1387 | p = buffer_ptr(&c->input); |
| 1388 | switch (p[0]) { |
| 1389 | case 0x04: |
| 1390 | ret = channel_decode_socks4(c, readset, writeset); |
| 1391 | break; |
| 1392 | case 0x05: |
| 1393 | ret = channel_decode_socks5(c, readset, writeset); |
| 1394 | break; |
| 1395 | default: |
| 1396 | ret = -1; |
| 1397 | break; |
| 1398 | } |
| 1399 | if (ret < 0) { |
| 1400 | chan_mark_dead(c); |
| 1401 | } else if (ret == 0) { |
| 1402 | debug2("channel %d: pre_dynamic: need more", c->self); |
| 1403 | /* need more */ |
| 1404 | FD_SET(c->sock, readset); |
| 1405 | } else { |
| 1406 | /* switch to the next state */ |
| 1407 | c->type = SSH_CHANNEL_OPENING; |
| 1408 | port_open_helper(c, "direct-tcpip"); |
| 1409 | } |
| 1410 | } |
| 1411 | |
| 1412 | /* This is our fake X11 server socket. */ |
| 1413 | /* ARGSUSED */ |
| 1414 | static void |
| 1415 | channel_post_x11_listener(Channel *c, fd_set *readset, fd_set *writeset) |
| 1416 | { |
| 1417 | Channel *nc; |
| 1418 | struct sockaddr_storage addr; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1419 | int newsock, oerrno; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1420 | socklen_t addrlen; |
| 1421 | char buf[16384], *remote_ipaddr; |
| 1422 | int remote_port; |
| 1423 | |
| 1424 | if (FD_ISSET(c->sock, readset)) { |
| 1425 | debug("X11 connection requested."); |
| 1426 | addrlen = sizeof(addr); |
| 1427 | newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen); |
| 1428 | if (c->single_connection) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1429 | oerrno = errno; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1430 | debug2("single_connection: closing X11 listener."); |
| 1431 | channel_close_fd(&c->sock); |
| 1432 | chan_mark_dead(c); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1433 | errno = oerrno; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1434 | } |
| 1435 | if (newsock < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1436 | if (errno != EINTR && errno != EWOULDBLOCK && |
| 1437 | errno != ECONNABORTED) |
| 1438 | error("accept: %.100s", strerror(errno)); |
| 1439 | if (errno == EMFILE || errno == ENFILE) |
| 1440 | c->notbefore = monotime() + 1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1441 | return; |
| 1442 | } |
| 1443 | set_nodelay(newsock); |
| 1444 | remote_ipaddr = get_peer_ipaddr(newsock); |
| 1445 | remote_port = get_peer_port(newsock); |
| 1446 | snprintf(buf, sizeof buf, "X11 connection from %.200s port %d", |
| 1447 | remote_ipaddr, remote_port); |
| 1448 | |
| 1449 | nc = channel_new("accepted x11 socket", |
| 1450 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
| 1451 | c->local_window_max, c->local_maxpacket, 0, buf, 1); |
| 1452 | if (compat20) { |
| 1453 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
| 1454 | packet_put_cstring("x11"); |
| 1455 | packet_put_int(nc->self); |
| 1456 | packet_put_int(nc->local_window_max); |
| 1457 | packet_put_int(nc->local_maxpacket); |
| 1458 | /* originator ipaddr and port */ |
| 1459 | packet_put_cstring(remote_ipaddr); |
| 1460 | if (datafellows & SSH_BUG_X11FWD) { |
| 1461 | debug2("ssh2 x11 bug compat mode"); |
| 1462 | } else { |
| 1463 | packet_put_int(remote_port); |
| 1464 | } |
| 1465 | packet_send(); |
| 1466 | } else { |
| 1467 | packet_start(SSH_SMSG_X11_OPEN); |
| 1468 | packet_put_int(nc->self); |
| 1469 | if (packet_get_protocol_flags() & |
| 1470 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) |
| 1471 | packet_put_cstring(buf); |
| 1472 | packet_send(); |
| 1473 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1474 | free(remote_ipaddr); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1475 | } |
| 1476 | } |
| 1477 | |
| 1478 | static void |
| 1479 | port_open_helper(Channel *c, char *rtype) |
| 1480 | { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1481 | char buf[1024]; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1482 | char *local_ipaddr = get_local_ipaddr(c->sock); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 1483 | int local_port = c->sock == -1 ? 65536 : get_local_port(c->sock); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1484 | char *remote_ipaddr = get_peer_ipaddr(c->sock); |
| 1485 | int remote_port = get_peer_port(c->sock); |
| 1486 | |
| 1487 | if (remote_port == -1) { |
| 1488 | /* Fake addr/port to appease peers that validate it (Tectia) */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1489 | free(remote_ipaddr); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1490 | remote_ipaddr = xstrdup("127.0.0.1"); |
| 1491 | remote_port = 65535; |
| 1492 | } |
| 1493 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1494 | snprintf(buf, sizeof buf, |
| 1495 | "%s: listening port %d for %.100s port %d, " |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1496 | "connect from %.200s port %d to %.100s port %d", |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1497 | rtype, c->listening_port, c->path, c->host_port, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1498 | remote_ipaddr, remote_port, local_ipaddr, local_port); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1499 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1500 | free(c->remote_name); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1501 | c->remote_name = xstrdup(buf); |
| 1502 | |
| 1503 | if (compat20) { |
| 1504 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
| 1505 | packet_put_cstring(rtype); |
| 1506 | packet_put_int(c->self); |
| 1507 | packet_put_int(c->local_window_max); |
| 1508 | packet_put_int(c->local_maxpacket); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1509 | if (strcmp(rtype, "direct-tcpip") == 0) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1510 | /* target host, port */ |
| 1511 | packet_put_cstring(c->path); |
| 1512 | packet_put_int(c->host_port); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1513 | } else if (strcmp(rtype, "direct-streamlocal@openssh.com") == 0) { |
| 1514 | /* target path */ |
| 1515 | packet_put_cstring(c->path); |
| 1516 | } else if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) { |
| 1517 | /* listen path */ |
| 1518 | packet_put_cstring(c->path); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1519 | } else { |
| 1520 | /* listen address, port */ |
| 1521 | packet_put_cstring(c->path); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1522 | packet_put_int(local_port); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1523 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1524 | if (strcmp(rtype, "forwarded-streamlocal@openssh.com") == 0) { |
| 1525 | /* reserved for future owner/mode info */ |
| 1526 | packet_put_cstring(""); |
| 1527 | } else { |
| 1528 | /* originator host and port */ |
| 1529 | packet_put_cstring(remote_ipaddr); |
| 1530 | packet_put_int((u_int)remote_port); |
| 1531 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1532 | packet_send(); |
| 1533 | } else { |
| 1534 | packet_start(SSH_MSG_PORT_OPEN); |
| 1535 | packet_put_int(c->self); |
| 1536 | packet_put_cstring(c->path); |
| 1537 | packet_put_int(c->host_port); |
| 1538 | if (packet_get_protocol_flags() & |
| 1539 | SSH_PROTOFLAG_HOST_IN_FWD_OPEN) |
| 1540 | packet_put_cstring(c->remote_name); |
| 1541 | packet_send(); |
| 1542 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1543 | free(remote_ipaddr); |
| 1544 | free(local_ipaddr); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1545 | } |
| 1546 | |
| 1547 | static void |
| 1548 | channel_set_reuseaddr(int fd) |
| 1549 | { |
| 1550 | int on = 1; |
| 1551 | |
| 1552 | /* |
| 1553 | * Set socket options. |
| 1554 | * Allow local port reuse in TIME_WAIT. |
| 1555 | */ |
| 1556 | if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) |
| 1557 | error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno)); |
| 1558 | } |
| 1559 | |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 1560 | void |
| 1561 | channel_set_x11_refuse_time(u_int refuse_time) |
| 1562 | { |
| 1563 | x11_refuse_time = refuse_time; |
| 1564 | } |
| 1565 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1566 | /* |
| 1567 | * This socket is listening for connections to a forwarded TCP/IP port. |
| 1568 | */ |
| 1569 | /* ARGSUSED */ |
| 1570 | static void |
| 1571 | channel_post_port_listener(Channel *c, fd_set *readset, fd_set *writeset) |
| 1572 | { |
| 1573 | Channel *nc; |
| 1574 | struct sockaddr_storage addr; |
| 1575 | int newsock, nextstate; |
| 1576 | socklen_t addrlen; |
| 1577 | char *rtype; |
| 1578 | |
| 1579 | if (FD_ISSET(c->sock, readset)) { |
| 1580 | debug("Connection to port %d forwarding " |
| 1581 | "to %.100s port %d requested.", |
| 1582 | c->listening_port, c->path, c->host_port); |
| 1583 | |
| 1584 | if (c->type == SSH_CHANNEL_RPORT_LISTENER) { |
| 1585 | nextstate = SSH_CHANNEL_OPENING; |
| 1586 | rtype = "forwarded-tcpip"; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1587 | } else if (c->type == SSH_CHANNEL_RUNIX_LISTENER) { |
| 1588 | nextstate = SSH_CHANNEL_OPENING; |
| 1589 | rtype = "forwarded-streamlocal@openssh.com"; |
| 1590 | } else if (c->host_port == PORT_STREAMLOCAL) { |
| 1591 | nextstate = SSH_CHANNEL_OPENING; |
| 1592 | rtype = "direct-streamlocal@openssh.com"; |
| 1593 | } else if (c->host_port == 0) { |
| 1594 | nextstate = SSH_CHANNEL_DYNAMIC; |
| 1595 | rtype = "dynamic-tcpip"; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1596 | } else { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1597 | nextstate = SSH_CHANNEL_OPENING; |
| 1598 | rtype = "direct-tcpip"; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1599 | } |
| 1600 | |
| 1601 | addrlen = sizeof(addr); |
| 1602 | newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen); |
| 1603 | if (newsock < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1604 | if (errno != EINTR && errno != EWOULDBLOCK && |
| 1605 | errno != ECONNABORTED) |
| 1606 | error("accept: %.100s", strerror(errno)); |
| 1607 | if (errno == EMFILE || errno == ENFILE) |
| 1608 | c->notbefore = monotime() + 1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1609 | return; |
| 1610 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1611 | if (c->host_port != PORT_STREAMLOCAL) |
| 1612 | set_nodelay(newsock); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1613 | nc = channel_new(rtype, nextstate, newsock, newsock, -1, |
| 1614 | c->local_window_max, c->local_maxpacket, 0, rtype, 1); |
| 1615 | nc->listening_port = c->listening_port; |
| 1616 | nc->host_port = c->host_port; |
| 1617 | if (c->path != NULL) |
| 1618 | nc->path = xstrdup(c->path); |
| 1619 | |
| 1620 | if (nextstate != SSH_CHANNEL_DYNAMIC) |
| 1621 | port_open_helper(nc, rtype); |
| 1622 | } |
| 1623 | } |
| 1624 | |
| 1625 | /* |
| 1626 | * This is the authentication agent socket listening for connections from |
| 1627 | * clients. |
| 1628 | */ |
| 1629 | /* ARGSUSED */ |
| 1630 | static void |
| 1631 | channel_post_auth_listener(Channel *c, fd_set *readset, fd_set *writeset) |
| 1632 | { |
| 1633 | Channel *nc; |
| 1634 | int newsock; |
| 1635 | struct sockaddr_storage addr; |
| 1636 | socklen_t addrlen; |
| 1637 | |
| 1638 | if (FD_ISSET(c->sock, readset)) { |
| 1639 | addrlen = sizeof(addr); |
| 1640 | newsock = accept(c->sock, (struct sockaddr *)&addr, &addrlen); |
| 1641 | if (newsock < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1642 | error("accept from auth socket: %.100s", |
| 1643 | strerror(errno)); |
| 1644 | if (errno == EMFILE || errno == ENFILE) |
| 1645 | c->notbefore = monotime() + 1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1646 | return; |
| 1647 | } |
| 1648 | nc = channel_new("accepted auth socket", |
| 1649 | SSH_CHANNEL_OPENING, newsock, newsock, -1, |
| 1650 | c->local_window_max, c->local_maxpacket, |
| 1651 | 0, "accepted auth socket", 1); |
| 1652 | if (compat20) { |
| 1653 | packet_start(SSH2_MSG_CHANNEL_OPEN); |
| 1654 | packet_put_cstring("auth-agent@openssh.com"); |
| 1655 | packet_put_int(nc->self); |
| 1656 | packet_put_int(c->local_window_max); |
| 1657 | packet_put_int(c->local_maxpacket); |
| 1658 | } else { |
| 1659 | packet_start(SSH_SMSG_AGENT_OPEN); |
| 1660 | packet_put_int(nc->self); |
| 1661 | } |
| 1662 | packet_send(); |
| 1663 | } |
| 1664 | } |
| 1665 | |
| 1666 | /* ARGSUSED */ |
| 1667 | static void |
| 1668 | channel_post_connecting(Channel *c, fd_set *readset, fd_set *writeset) |
| 1669 | { |
| 1670 | int err = 0, sock; |
| 1671 | socklen_t sz = sizeof(err); |
| 1672 | |
| 1673 | if (FD_ISSET(c->sock, writeset)) { |
| 1674 | if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) { |
| 1675 | err = errno; |
| 1676 | error("getsockopt SO_ERROR failed"); |
| 1677 | } |
| 1678 | if (err == 0) { |
| 1679 | debug("channel %d: connected to %s port %d", |
| 1680 | c->self, c->connect_ctx.host, c->connect_ctx.port); |
| 1681 | channel_connect_ctx_free(&c->connect_ctx); |
| 1682 | c->type = SSH_CHANNEL_OPEN; |
| 1683 | if (compat20) { |
| 1684 | packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION); |
| 1685 | packet_put_int(c->remote_id); |
| 1686 | packet_put_int(c->self); |
| 1687 | packet_put_int(c->local_window); |
| 1688 | packet_put_int(c->local_maxpacket); |
| 1689 | } else { |
| 1690 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); |
| 1691 | packet_put_int(c->remote_id); |
| 1692 | packet_put_int(c->self); |
| 1693 | } |
| 1694 | } else { |
| 1695 | debug("channel %d: connection failed: %s", |
| 1696 | c->self, strerror(err)); |
| 1697 | /* Try next address, if any */ |
| 1698 | if ((sock = connect_next(&c->connect_ctx)) > 0) { |
| 1699 | close(c->sock); |
| 1700 | c->sock = c->rfd = c->wfd = sock; |
| 1701 | channel_max_fd = channel_find_maxfd(); |
| 1702 | return; |
| 1703 | } |
| 1704 | /* Exhausted all addresses */ |
| 1705 | error("connect_to %.100s port %d: failed.", |
| 1706 | c->connect_ctx.host, c->connect_ctx.port); |
| 1707 | channel_connect_ctx_free(&c->connect_ctx); |
| 1708 | if (compat20) { |
| 1709 | packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE); |
| 1710 | packet_put_int(c->remote_id); |
| 1711 | packet_put_int(SSH2_OPEN_CONNECT_FAILED); |
| 1712 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
| 1713 | packet_put_cstring(strerror(err)); |
| 1714 | packet_put_cstring(""); |
| 1715 | } |
| 1716 | } else { |
| 1717 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
| 1718 | packet_put_int(c->remote_id); |
| 1719 | } |
| 1720 | chan_mark_dead(c); |
| 1721 | } |
| 1722 | packet_send(); |
| 1723 | } |
| 1724 | } |
| 1725 | |
| 1726 | /* ARGSUSED */ |
| 1727 | static int |
| 1728 | channel_handle_rfd(Channel *c, fd_set *readset, fd_set *writeset) |
| 1729 | { |
| 1730 | char buf[CHAN_RBUF]; |
| 1731 | int len, force; |
| 1732 | |
| 1733 | force = c->isatty && c->detach_close && c->istate != CHAN_INPUT_CLOSED; |
| 1734 | if (c->rfd != -1 && (force || FD_ISSET(c->rfd, readset))) { |
| 1735 | errno = 0; |
| 1736 | len = read(c->rfd, buf, sizeof(buf)); |
| 1737 | if (len < 0 && (errno == EINTR || |
| 1738 | ((errno == EAGAIN || errno == EWOULDBLOCK) && !force))) |
| 1739 | return 1; |
| 1740 | #ifndef PTY_ZEROREAD |
| 1741 | if (len <= 0) { |
| 1742 | #else |
| 1743 | if ((!c->isatty && len <= 0) || |
| 1744 | (c->isatty && (len < 0 || (len == 0 && errno != 0)))) { |
| 1745 | #endif |
| 1746 | debug2("channel %d: read<=0 rfd %d len %d", |
| 1747 | c->self, c->rfd, len); |
| 1748 | if (c->type != SSH_CHANNEL_OPEN) { |
| 1749 | debug2("channel %d: not open", c->self); |
| 1750 | chan_mark_dead(c); |
| 1751 | return -1; |
| 1752 | } else if (compat13) { |
| 1753 | buffer_clear(&c->output); |
| 1754 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
| 1755 | debug2("channel %d: input draining.", c->self); |
| 1756 | } else { |
| 1757 | chan_read_failed(c); |
| 1758 | } |
| 1759 | return -1; |
| 1760 | } |
| 1761 | if (c->input_filter != NULL) { |
| 1762 | if (c->input_filter(c, buf, len) == -1) { |
| 1763 | debug2("channel %d: filter stops", c->self); |
| 1764 | chan_read_failed(c); |
| 1765 | } |
| 1766 | } else if (c->datagram) { |
| 1767 | buffer_put_string(&c->input, buf, len); |
| 1768 | } else { |
| 1769 | buffer_append(&c->input, buf, len); |
| 1770 | } |
| 1771 | } |
| 1772 | return 1; |
| 1773 | } |
| 1774 | |
| 1775 | /* ARGSUSED */ |
| 1776 | static int |
| 1777 | channel_handle_wfd(Channel *c, fd_set *readset, fd_set *writeset) |
| 1778 | { |
| 1779 | struct termios tio; |
| 1780 | u_char *data = NULL, *buf; |
| 1781 | u_int dlen, olen = 0; |
| 1782 | int len; |
| 1783 | |
| 1784 | /* Send buffered output data to the socket. */ |
| 1785 | if (c->wfd != -1 && |
| 1786 | FD_ISSET(c->wfd, writeset) && |
| 1787 | buffer_len(&c->output) > 0) { |
| 1788 | olen = buffer_len(&c->output); |
| 1789 | if (c->output_filter != NULL) { |
| 1790 | if ((buf = c->output_filter(c, &data, &dlen)) == NULL) { |
| 1791 | debug2("channel %d: filter stops", c->self); |
| 1792 | if (c->type != SSH_CHANNEL_OPEN) |
| 1793 | chan_mark_dead(c); |
| 1794 | else |
| 1795 | chan_write_failed(c); |
| 1796 | return -1; |
| 1797 | } |
| 1798 | } else if (c->datagram) { |
| 1799 | buf = data = buffer_get_string(&c->output, &dlen); |
| 1800 | } else { |
| 1801 | buf = data = buffer_ptr(&c->output); |
| 1802 | dlen = buffer_len(&c->output); |
| 1803 | } |
| 1804 | |
| 1805 | if (c->datagram) { |
| 1806 | /* ignore truncated writes, datagrams might get lost */ |
| 1807 | len = write(c->wfd, buf, dlen); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1808 | free(data); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1809 | if (len < 0 && (errno == EINTR || errno == EAGAIN || |
| 1810 | errno == EWOULDBLOCK)) |
| 1811 | return 1; |
| 1812 | if (len <= 0) { |
| 1813 | if (c->type != SSH_CHANNEL_OPEN) |
| 1814 | chan_mark_dead(c); |
| 1815 | else |
| 1816 | chan_write_failed(c); |
| 1817 | return -1; |
| 1818 | } |
| 1819 | goto out; |
| 1820 | } |
| 1821 | #ifdef _AIX |
| 1822 | /* XXX: Later AIX versions can't push as much data to tty */ |
| 1823 | if (compat20 && c->wfd_isatty) |
| 1824 | dlen = MIN(dlen, 8*1024); |
| 1825 | #endif |
| 1826 | |
| 1827 | len = write(c->wfd, buf, dlen); |
| 1828 | if (len < 0 && |
| 1829 | (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)) |
| 1830 | return 1; |
| 1831 | if (len <= 0) { |
| 1832 | if (c->type != SSH_CHANNEL_OPEN) { |
| 1833 | debug2("channel %d: not open", c->self); |
| 1834 | chan_mark_dead(c); |
| 1835 | return -1; |
| 1836 | } else if (compat13) { |
| 1837 | buffer_clear(&c->output); |
| 1838 | debug2("channel %d: input draining.", c->self); |
| 1839 | c->type = SSH_CHANNEL_INPUT_DRAINING; |
| 1840 | } else { |
| 1841 | chan_write_failed(c); |
| 1842 | } |
| 1843 | return -1; |
| 1844 | } |
| 1845 | #ifndef BROKEN_TCGETATTR_ICANON |
| 1846 | if (compat20 && c->isatty && dlen >= 1 && buf[0] != '\r') { |
| 1847 | if (tcgetattr(c->wfd, &tio) == 0 && |
| 1848 | !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) { |
| 1849 | /* |
| 1850 | * Simulate echo to reduce the impact of |
| 1851 | * traffic analysis. We need to match the |
| 1852 | * size of a SSH2_MSG_CHANNEL_DATA message |
| 1853 | * (4 byte channel id + buf) |
| 1854 | */ |
| 1855 | packet_send_ignore(4 + len); |
| 1856 | packet_send(); |
| 1857 | } |
| 1858 | } |
| 1859 | #endif |
| 1860 | buffer_consume(&c->output, len); |
| 1861 | } |
| 1862 | out: |
| 1863 | if (compat20 && olen > 0) |
| 1864 | c->local_consumed += olen - buffer_len(&c->output); |
| 1865 | return 1; |
| 1866 | } |
| 1867 | |
| 1868 | static int |
| 1869 | channel_handle_efd(Channel *c, fd_set *readset, fd_set *writeset) |
| 1870 | { |
| 1871 | char buf[CHAN_RBUF]; |
| 1872 | int len; |
| 1873 | |
| 1874 | /** XXX handle drain efd, too */ |
| 1875 | if (c->efd != -1) { |
| 1876 | if (c->extended_usage == CHAN_EXTENDED_WRITE && |
| 1877 | FD_ISSET(c->efd, writeset) && |
| 1878 | buffer_len(&c->extended) > 0) { |
| 1879 | len = write(c->efd, buffer_ptr(&c->extended), |
| 1880 | buffer_len(&c->extended)); |
| 1881 | debug2("channel %d: written %d to efd %d", |
| 1882 | c->self, len, c->efd); |
| 1883 | if (len < 0 && (errno == EINTR || errno == EAGAIN || |
| 1884 | errno == EWOULDBLOCK)) |
| 1885 | return 1; |
| 1886 | if (len <= 0) { |
| 1887 | debug2("channel %d: closing write-efd %d", |
| 1888 | c->self, c->efd); |
| 1889 | channel_close_fd(&c->efd); |
| 1890 | } else { |
| 1891 | buffer_consume(&c->extended, len); |
| 1892 | c->local_consumed += len; |
| 1893 | } |
| 1894 | } else if (c->efd != -1 && |
| 1895 | (c->extended_usage == CHAN_EXTENDED_READ || |
| 1896 | c->extended_usage == CHAN_EXTENDED_IGNORE) && |
| 1897 | (c->detach_close || FD_ISSET(c->efd, readset))) { |
| 1898 | len = read(c->efd, buf, sizeof(buf)); |
| 1899 | debug2("channel %d: read %d from efd %d", |
| 1900 | c->self, len, c->efd); |
| 1901 | if (len < 0 && (errno == EINTR || ((errno == EAGAIN || |
| 1902 | errno == EWOULDBLOCK) && !c->detach_close))) |
| 1903 | return 1; |
| 1904 | if (len <= 0) { |
| 1905 | debug2("channel %d: closing read-efd %d", |
| 1906 | c->self, c->efd); |
| 1907 | channel_close_fd(&c->efd); |
| 1908 | } else { |
| 1909 | if (c->extended_usage == CHAN_EXTENDED_IGNORE) { |
| 1910 | debug3("channel %d: discard efd", |
| 1911 | c->self); |
| 1912 | } else |
| 1913 | buffer_append(&c->extended, buf, len); |
| 1914 | } |
| 1915 | } |
| 1916 | } |
| 1917 | return 1; |
| 1918 | } |
| 1919 | |
| 1920 | static int |
| 1921 | channel_check_window(Channel *c) |
| 1922 | { |
| 1923 | if (c->type == SSH_CHANNEL_OPEN && |
| 1924 | !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) && |
| 1925 | ((c->local_window_max - c->local_window > |
| 1926 | c->local_maxpacket*3) || |
| 1927 | c->local_window < c->local_window_max/2) && |
| 1928 | c->local_consumed > 0) { |
| 1929 | packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST); |
| 1930 | packet_put_int(c->remote_id); |
| 1931 | packet_put_int(c->local_consumed); |
| 1932 | packet_send(); |
| 1933 | debug2("channel %d: window %d sent adjust %d", |
| 1934 | c->self, c->local_window, |
| 1935 | c->local_consumed); |
| 1936 | c->local_window += c->local_consumed; |
| 1937 | c->local_consumed = 0; |
| 1938 | } |
| 1939 | return 1; |
| 1940 | } |
| 1941 | |
| 1942 | static void |
| 1943 | channel_post_open(Channel *c, fd_set *readset, fd_set *writeset) |
| 1944 | { |
| 1945 | channel_handle_rfd(c, readset, writeset); |
| 1946 | channel_handle_wfd(c, readset, writeset); |
| 1947 | if (!compat20) |
| 1948 | return; |
| 1949 | channel_handle_efd(c, readset, writeset); |
| 1950 | channel_check_window(c); |
| 1951 | } |
| 1952 | |
| 1953 | static u_int |
| 1954 | read_mux(Channel *c, u_int need) |
| 1955 | { |
| 1956 | char buf[CHAN_RBUF]; |
| 1957 | int len; |
| 1958 | u_int rlen; |
| 1959 | |
| 1960 | if (buffer_len(&c->input) < need) { |
| 1961 | rlen = need - buffer_len(&c->input); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 1962 | len = read(c->rfd, buf, MINIMUM(rlen, CHAN_RBUF)); |
| 1963 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
| 1964 | return buffer_len(&c->input); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1965 | if (len <= 0) { |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 1966 | debug2("channel %d: ctl read<=0 rfd %d len %d", |
| 1967 | c->self, c->rfd, len); |
| 1968 | chan_read_failed(c); |
| 1969 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1970 | } else |
| 1971 | buffer_append(&c->input, buf, len); |
| 1972 | } |
| 1973 | return buffer_len(&c->input); |
| 1974 | } |
| 1975 | |
| 1976 | static void |
| 1977 | channel_post_mux_client(Channel *c, fd_set *readset, fd_set *writeset) |
| 1978 | { |
| 1979 | u_int need; |
| 1980 | ssize_t len; |
| 1981 | |
| 1982 | if (!compat20) |
| 1983 | fatal("%s: entered with !compat20", __func__); |
| 1984 | |
| 1985 | if (c->rfd != -1 && !c->mux_pause && FD_ISSET(c->rfd, readset) && |
| 1986 | (c->istate == CHAN_INPUT_OPEN || |
| 1987 | c->istate == CHAN_INPUT_WAIT_DRAIN)) { |
| 1988 | /* |
| 1989 | * Don't not read past the precise end of packets to |
| 1990 | * avoid disrupting fd passing. |
| 1991 | */ |
| 1992 | if (read_mux(c, 4) < 4) /* read header */ |
| 1993 | return; |
| 1994 | need = get_u32(buffer_ptr(&c->input)); |
| 1995 | #define CHANNEL_MUX_MAX_PACKET (256 * 1024) |
| 1996 | if (need > CHANNEL_MUX_MAX_PACKET) { |
| 1997 | debug2("channel %d: packet too big %u > %u", |
| 1998 | c->self, CHANNEL_MUX_MAX_PACKET, need); |
| 1999 | chan_rcvd_oclose(c); |
| 2000 | return; |
| 2001 | } |
| 2002 | if (read_mux(c, need + 4) < need + 4) /* read body */ |
| 2003 | return; |
| 2004 | if (c->mux_rcb(c) != 0) { |
| 2005 | debug("channel %d: mux_rcb failed", c->self); |
| 2006 | chan_mark_dead(c); |
| 2007 | return; |
| 2008 | } |
| 2009 | } |
| 2010 | |
| 2011 | if (c->wfd != -1 && FD_ISSET(c->wfd, writeset) && |
| 2012 | buffer_len(&c->output) > 0) { |
| 2013 | len = write(c->wfd, buffer_ptr(&c->output), |
| 2014 | buffer_len(&c->output)); |
| 2015 | if (len < 0 && (errno == EINTR || errno == EAGAIN)) |
| 2016 | return; |
| 2017 | if (len <= 0) { |
| 2018 | chan_mark_dead(c); |
| 2019 | return; |
| 2020 | } |
| 2021 | buffer_consume(&c->output, len); |
| 2022 | } |
| 2023 | } |
| 2024 | |
| 2025 | static void |
| 2026 | channel_post_mux_listener(Channel *c, fd_set *readset, fd_set *writeset) |
| 2027 | { |
| 2028 | Channel *nc; |
| 2029 | struct sockaddr_storage addr; |
| 2030 | socklen_t addrlen; |
| 2031 | int newsock; |
| 2032 | uid_t euid; |
| 2033 | gid_t egid; |
| 2034 | |
| 2035 | if (!FD_ISSET(c->sock, readset)) |
| 2036 | return; |
| 2037 | |
| 2038 | debug("multiplexing control connection"); |
| 2039 | |
| 2040 | /* |
| 2041 | * Accept connection on control socket |
| 2042 | */ |
| 2043 | memset(&addr, 0, sizeof(addr)); |
| 2044 | addrlen = sizeof(addr); |
| 2045 | if ((newsock = accept(c->sock, (struct sockaddr*)&addr, |
| 2046 | &addrlen)) == -1) { |
| 2047 | error("%s accept: %s", __func__, strerror(errno)); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2048 | if (errno == EMFILE || errno == ENFILE) |
| 2049 | c->notbefore = monotime() + 1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2050 | return; |
| 2051 | } |
| 2052 | |
| 2053 | if (getpeereid(newsock, &euid, &egid) < 0) { |
| 2054 | error("%s getpeereid failed: %s", __func__, |
| 2055 | strerror(errno)); |
| 2056 | close(newsock); |
| 2057 | return; |
| 2058 | } |
| 2059 | if ((euid != 0) && (getuid() != euid)) { |
| 2060 | error("multiplex uid mismatch: peer euid %u != uid %u", |
| 2061 | (u_int)euid, (u_int)getuid()); |
| 2062 | close(newsock); |
| 2063 | return; |
| 2064 | } |
| 2065 | nc = channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT, |
| 2066 | newsock, newsock, -1, c->local_window_max, |
| 2067 | c->local_maxpacket, 0, "mux-control", 1); |
| 2068 | nc->mux_rcb = c->mux_rcb; |
| 2069 | debug3("%s: new mux channel %d fd %d", __func__, |
| 2070 | nc->self, nc->sock); |
| 2071 | /* establish state */ |
| 2072 | nc->mux_rcb(nc); |
| 2073 | /* mux state transitions must not elicit protocol messages */ |
| 2074 | nc->flags |= CHAN_LOCAL; |
| 2075 | } |
| 2076 | |
| 2077 | /* ARGSUSED */ |
| 2078 | static void |
| 2079 | channel_post_output_drain_13(Channel *c, fd_set *readset, fd_set *writeset) |
| 2080 | { |
| 2081 | int len; |
| 2082 | |
| 2083 | /* Send buffered output data to the socket. */ |
| 2084 | if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) { |
| 2085 | len = write(c->sock, buffer_ptr(&c->output), |
| 2086 | buffer_len(&c->output)); |
| 2087 | if (len <= 0) |
| 2088 | buffer_clear(&c->output); |
| 2089 | else |
| 2090 | buffer_consume(&c->output, len); |
| 2091 | } |
| 2092 | } |
| 2093 | |
| 2094 | static void |
| 2095 | channel_handler_init_20(void) |
| 2096 | { |
| 2097 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
| 2098 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
| 2099 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
| 2100 | channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2101 | channel_pre[SSH_CHANNEL_UNIX_LISTENER] = &channel_pre_listener; |
| 2102 | channel_pre[SSH_CHANNEL_RUNIX_LISTENER] = &channel_pre_listener; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2103 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
| 2104 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
| 2105 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
| 2106 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
| 2107 | channel_pre[SSH_CHANNEL_MUX_LISTENER] = &channel_pre_listener; |
| 2108 | channel_pre[SSH_CHANNEL_MUX_CLIENT] = &channel_pre_mux_client; |
| 2109 | |
| 2110 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
| 2111 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; |
| 2112 | channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2113 | channel_post[SSH_CHANNEL_UNIX_LISTENER] = &channel_post_port_listener; |
| 2114 | channel_post[SSH_CHANNEL_RUNIX_LISTENER] = &channel_post_port_listener; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2115 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
| 2116 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
| 2117 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
| 2118 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
| 2119 | channel_post[SSH_CHANNEL_MUX_LISTENER] = &channel_post_mux_listener; |
| 2120 | channel_post[SSH_CHANNEL_MUX_CLIENT] = &channel_post_mux_client; |
| 2121 | } |
| 2122 | |
| 2123 | static void |
| 2124 | channel_handler_init_13(void) |
| 2125 | { |
| 2126 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13; |
| 2127 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13; |
| 2128 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
| 2129 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
| 2130 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
| 2131 | channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining; |
| 2132 | channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining; |
| 2133 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
| 2134 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
| 2135 | |
| 2136 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
| 2137 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
| 2138 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; |
| 2139 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
| 2140 | channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13; |
| 2141 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
| 2142 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
| 2143 | } |
| 2144 | |
| 2145 | static void |
| 2146 | channel_handler_init_15(void) |
| 2147 | { |
| 2148 | channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open; |
| 2149 | channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open; |
| 2150 | channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener; |
| 2151 | channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener; |
| 2152 | channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener; |
| 2153 | channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting; |
| 2154 | channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic; |
| 2155 | |
| 2156 | channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener; |
| 2157 | channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener; |
| 2158 | channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener; |
| 2159 | channel_post[SSH_CHANNEL_OPEN] = &channel_post_open; |
| 2160 | channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting; |
| 2161 | channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open; |
| 2162 | } |
| 2163 | |
| 2164 | static void |
| 2165 | channel_handler_init(void) |
| 2166 | { |
| 2167 | int i; |
| 2168 | |
| 2169 | for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) { |
| 2170 | channel_pre[i] = NULL; |
| 2171 | channel_post[i] = NULL; |
| 2172 | } |
| 2173 | if (compat20) |
| 2174 | channel_handler_init_20(); |
| 2175 | else if (compat13) |
| 2176 | channel_handler_init_13(); |
| 2177 | else |
| 2178 | channel_handler_init_15(); |
| 2179 | } |
| 2180 | |
| 2181 | /* gc dead channels */ |
| 2182 | static void |
| 2183 | channel_garbage_collect(Channel *c) |
| 2184 | { |
| 2185 | if (c == NULL) |
| 2186 | return; |
| 2187 | if (c->detach_user != NULL) { |
| 2188 | if (!chan_is_dead(c, c->detach_close)) |
| 2189 | return; |
| 2190 | debug2("channel %d: gc: notify user", c->self); |
| 2191 | c->detach_user(c->self, NULL); |
| 2192 | /* if we still have a callback */ |
| 2193 | if (c->detach_user != NULL) |
| 2194 | return; |
| 2195 | debug2("channel %d: gc: user detached", c->self); |
| 2196 | } |
| 2197 | if (!chan_is_dead(c, 1)) |
| 2198 | return; |
| 2199 | debug2("channel %d: garbage collecting", c->self); |
| 2200 | channel_free(c); |
| 2201 | } |
| 2202 | |
| 2203 | static void |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2204 | channel_handler(chan_fn *ftab[], fd_set *readset, fd_set *writeset, |
| 2205 | time_t *unpause_secs) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2206 | { |
| 2207 | static int did_init = 0; |
| 2208 | u_int i, oalloc; |
| 2209 | Channel *c; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2210 | time_t now; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2211 | |
| 2212 | if (!did_init) { |
| 2213 | channel_handler_init(); |
| 2214 | did_init = 1; |
| 2215 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2216 | now = monotime(); |
| 2217 | if (unpause_secs != NULL) |
| 2218 | *unpause_secs = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2219 | for (i = 0, oalloc = channels_alloc; i < oalloc; i++) { |
| 2220 | c = channels[i]; |
| 2221 | if (c == NULL) |
| 2222 | continue; |
| 2223 | if (c->delayed) { |
| 2224 | if (ftab == channel_pre) |
| 2225 | c->delayed = 0; |
| 2226 | else |
| 2227 | continue; |
| 2228 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2229 | if (ftab[c->type] != NULL) { |
| 2230 | /* |
| 2231 | * Run handlers that are not paused. |
| 2232 | */ |
| 2233 | if (c->notbefore <= now) |
| 2234 | (*ftab[c->type])(c, readset, writeset); |
| 2235 | else if (unpause_secs != NULL) { |
| 2236 | /* |
| 2237 | * Collect the time that the earliest |
| 2238 | * channel comes off pause. |
| 2239 | */ |
| 2240 | debug3("%s: chan %d: skip for %d more seconds", |
| 2241 | __func__, c->self, |
| 2242 | (int)(c->notbefore - now)); |
| 2243 | if (*unpause_secs == 0 || |
| 2244 | (c->notbefore - now) < *unpause_secs) |
| 2245 | *unpause_secs = c->notbefore - now; |
| 2246 | } |
| 2247 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2248 | channel_garbage_collect(c); |
| 2249 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2250 | if (unpause_secs != NULL && *unpause_secs != 0) |
| 2251 | debug3("%s: first channel unpauses in %d seconds", |
| 2252 | __func__, (int)*unpause_secs); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2253 | } |
| 2254 | |
| 2255 | /* |
| 2256 | * Allocate/update select bitmasks and add any bits relevant to channels in |
| 2257 | * select bitmasks. |
| 2258 | */ |
| 2259 | void |
| 2260 | channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2261 | u_int *nallocp, time_t *minwait_secs, int rekeying) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2262 | { |
| 2263 | u_int n, sz, nfdset; |
| 2264 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2265 | n = MAXIMUM(*maxfdp, channel_max_fd); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2266 | |
| 2267 | nfdset = howmany(n+1, NFDBITS); |
| 2268 | /* Explicitly test here, because xrealloc isn't always called */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2269 | if (nfdset && SIZE_MAX / nfdset < sizeof(fd_mask)) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2270 | fatal("channel_prepare_select: max_fd (%d) is too large", n); |
| 2271 | sz = nfdset * sizeof(fd_mask); |
| 2272 | |
| 2273 | /* perhaps check sz < nalloc/2 and shrink? */ |
| 2274 | if (*readsetp == NULL || sz > *nallocp) { |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 2275 | *readsetp = xreallocarray(*readsetp, nfdset, sizeof(fd_mask)); |
| 2276 | *writesetp = xreallocarray(*writesetp, nfdset, sizeof(fd_mask)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2277 | *nallocp = sz; |
| 2278 | } |
| 2279 | *maxfdp = n; |
| 2280 | memset(*readsetp, 0, sz); |
| 2281 | memset(*writesetp, 0, sz); |
| 2282 | |
| 2283 | if (!rekeying) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2284 | channel_handler(channel_pre, *readsetp, *writesetp, |
| 2285 | minwait_secs); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2286 | } |
| 2287 | |
| 2288 | /* |
| 2289 | * After select, perform any appropriate operations for channels which have |
| 2290 | * events pending. |
| 2291 | */ |
| 2292 | void |
| 2293 | channel_after_select(fd_set *readset, fd_set *writeset) |
| 2294 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2295 | channel_handler(channel_post, readset, writeset, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2296 | } |
| 2297 | |
| 2298 | |
| 2299 | /* If there is data to send to the connection, enqueue some of it now. */ |
| 2300 | void |
| 2301 | channel_output_poll(void) |
| 2302 | { |
| 2303 | Channel *c; |
| 2304 | u_int i, len; |
| 2305 | |
| 2306 | for (i = 0; i < channels_alloc; i++) { |
| 2307 | c = channels[i]; |
| 2308 | if (c == NULL) |
| 2309 | continue; |
| 2310 | |
| 2311 | /* |
| 2312 | * We are only interested in channels that can have buffered |
| 2313 | * incoming data. |
| 2314 | */ |
| 2315 | if (compat13) { |
| 2316 | if (c->type != SSH_CHANNEL_OPEN && |
| 2317 | c->type != SSH_CHANNEL_INPUT_DRAINING) |
| 2318 | continue; |
| 2319 | } else { |
| 2320 | if (c->type != SSH_CHANNEL_OPEN) |
| 2321 | continue; |
| 2322 | } |
| 2323 | if (compat20 && |
| 2324 | (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) { |
| 2325 | /* XXX is this true? */ |
| 2326 | debug3("channel %d: will not send data after close", c->self); |
| 2327 | continue; |
| 2328 | } |
| 2329 | |
| 2330 | /* Get the amount of buffered data for this channel. */ |
| 2331 | if ((c->istate == CHAN_INPUT_OPEN || |
| 2332 | c->istate == CHAN_INPUT_WAIT_DRAIN) && |
| 2333 | (len = buffer_len(&c->input)) > 0) { |
| 2334 | if (c->datagram) { |
| 2335 | if (len > 0) { |
| 2336 | u_char *data; |
| 2337 | u_int dlen; |
| 2338 | |
| 2339 | data = buffer_get_string(&c->input, |
| 2340 | &dlen); |
| 2341 | if (dlen > c->remote_window || |
| 2342 | dlen > c->remote_maxpacket) { |
| 2343 | debug("channel %d: datagram " |
| 2344 | "too big for channel", |
| 2345 | c->self); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2346 | free(data); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2347 | continue; |
| 2348 | } |
| 2349 | packet_start(SSH2_MSG_CHANNEL_DATA); |
| 2350 | packet_put_int(c->remote_id); |
| 2351 | packet_put_string(data, dlen); |
| 2352 | packet_send(); |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 2353 | c->remote_window -= dlen; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2354 | free(data); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2355 | } |
| 2356 | continue; |
| 2357 | } |
| 2358 | /* |
| 2359 | * Send some data for the other side over the secure |
| 2360 | * connection. |
| 2361 | */ |
| 2362 | if (compat20) { |
| 2363 | if (len > c->remote_window) |
| 2364 | len = c->remote_window; |
| 2365 | if (len > c->remote_maxpacket) |
| 2366 | len = c->remote_maxpacket; |
| 2367 | } else { |
| 2368 | if (packet_is_interactive()) { |
| 2369 | if (len > 1024) |
| 2370 | len = 512; |
| 2371 | } else { |
| 2372 | /* Keep the packets at reasonable size. */ |
| 2373 | if (len > packet_get_maxsize()/2) |
| 2374 | len = packet_get_maxsize()/2; |
| 2375 | } |
| 2376 | } |
| 2377 | if (len > 0) { |
| 2378 | packet_start(compat20 ? |
| 2379 | SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA); |
| 2380 | packet_put_int(c->remote_id); |
| 2381 | packet_put_string(buffer_ptr(&c->input), len); |
| 2382 | packet_send(); |
| 2383 | buffer_consume(&c->input, len); |
| 2384 | c->remote_window -= len; |
| 2385 | } |
| 2386 | } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) { |
| 2387 | if (compat13) |
| 2388 | fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3"); |
| 2389 | /* |
| 2390 | * input-buffer is empty and read-socket shutdown: |
| 2391 | * tell peer, that we will not send more data: send IEOF. |
| 2392 | * hack for extended data: delay EOF if EFD still in use. |
| 2393 | */ |
| 2394 | if (CHANNEL_EFD_INPUT_ACTIVE(c)) |
| 2395 | debug2("channel %d: ibuf_empty delayed efd %d/(%d)", |
| 2396 | c->self, c->efd, buffer_len(&c->extended)); |
| 2397 | else |
| 2398 | chan_ibuf_empty(c); |
| 2399 | } |
| 2400 | /* Send extended data, i.e. stderr */ |
| 2401 | if (compat20 && |
| 2402 | !(c->flags & CHAN_EOF_SENT) && |
| 2403 | c->remote_window > 0 && |
| 2404 | (len = buffer_len(&c->extended)) > 0 && |
| 2405 | c->extended_usage == CHAN_EXTENDED_READ) { |
| 2406 | debug2("channel %d: rwin %u elen %u euse %d", |
| 2407 | c->self, c->remote_window, buffer_len(&c->extended), |
| 2408 | c->extended_usage); |
| 2409 | if (len > c->remote_window) |
| 2410 | len = c->remote_window; |
| 2411 | if (len > c->remote_maxpacket) |
| 2412 | len = c->remote_maxpacket; |
| 2413 | packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA); |
| 2414 | packet_put_int(c->remote_id); |
| 2415 | packet_put_int(SSH2_EXTENDED_DATA_STDERR); |
| 2416 | packet_put_string(buffer_ptr(&c->extended), len); |
| 2417 | packet_send(); |
| 2418 | buffer_consume(&c->extended, len); |
| 2419 | c->remote_window -= len; |
| 2420 | debug2("channel %d: sent ext data %d", c->self, len); |
| 2421 | } |
| 2422 | } |
| 2423 | } |
| 2424 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2425 | /* -- mux proxy support */ |
| 2426 | |
| 2427 | /* |
| 2428 | * When multiplexing channel messages for mux clients we have to deal |
| 2429 | * with downstream messages from the mux client and upstream messages |
| 2430 | * from the ssh server: |
| 2431 | * 1) Handling downstream messages is straightforward and happens |
| 2432 | * in channel_proxy_downstream(): |
| 2433 | * - We forward all messages (mostly) unmodified to the server. |
| 2434 | * - However, in order to route messages from upstream to the correct |
| 2435 | * downstream client, we have to replace the channel IDs used by the |
| 2436 | * mux clients with a unique channel ID because the mux clients might |
| 2437 | * use conflicting channel IDs. |
| 2438 | * - so we inspect and change both SSH2_MSG_CHANNEL_OPEN and |
| 2439 | * SSH2_MSG_CHANNEL_OPEN_CONFIRMATION messages, create a local |
| 2440 | * SSH_CHANNEL_MUX_PROXY channel and replace the mux clients ID |
| 2441 | * with the newly allocated channel ID. |
| 2442 | * 2) Upstream messages are received by matching SSH_CHANNEL_MUX_PROXY |
| 2443 | * channels and procesed by channel_proxy_upstream(). The local channel ID |
| 2444 | * is then translated back to the original mux client ID. |
| 2445 | * 3) In both cases we need to keep track of matching SSH2_MSG_CHANNEL_CLOSE |
| 2446 | * messages so we can clean up SSH_CHANNEL_MUX_PROXY channels. |
| 2447 | * 4) The SSH_CHANNEL_MUX_PROXY channels also need to closed when the |
| 2448 | * downstream mux client are removed. |
| 2449 | * 5) Handling SSH2_MSG_CHANNEL_OPEN messages from the upstream server |
| 2450 | * requires more work, because they are not addressed to a specific |
| 2451 | * channel. E.g. client_request_forwarded_tcpip() needs to figure |
| 2452 | * out whether the request is addressed to the local client or a |
| 2453 | * specific downstream client based on the listen-address/port. |
| 2454 | * 6) Agent and X11-Forwarding have a similar problem and are currenly |
| 2455 | * not supported as the matching session/channel cannot be identified |
| 2456 | * easily. |
| 2457 | */ |
| 2458 | |
| 2459 | /* |
| 2460 | * receive packets from downstream mux clients: |
| 2461 | * channel callback fired on read from mux client, creates |
| 2462 | * SSH_CHANNEL_MUX_PROXY channels and translates channel IDs |
| 2463 | * on channel creation. |
| 2464 | */ |
| 2465 | int |
| 2466 | channel_proxy_downstream(Channel *downstream) |
| 2467 | { |
| 2468 | Channel *c = NULL; |
| 2469 | struct ssh *ssh = active_state; |
| 2470 | struct sshbuf *original = NULL, *modified = NULL; |
| 2471 | const u_char *cp; |
| 2472 | char *ctype = NULL, *listen_host = NULL; |
| 2473 | u_char type; |
| 2474 | size_t have; |
| 2475 | int ret = -1, r, idx; |
| 2476 | u_int id, remote_id, listen_port; |
| 2477 | |
| 2478 | /* sshbuf_dump(&downstream->input, stderr); */ |
| 2479 | if ((r = sshbuf_get_string_direct(&downstream->input, &cp, &have)) |
| 2480 | != 0) { |
| 2481 | error("%s: malformed message: %s", __func__, ssh_err(r)); |
| 2482 | return -1; |
| 2483 | } |
| 2484 | if (have < 2) { |
| 2485 | error("%s: short message", __func__); |
| 2486 | return -1; |
| 2487 | } |
| 2488 | type = cp[1]; |
| 2489 | /* skip padlen + type */ |
| 2490 | cp += 2; |
| 2491 | have -= 2; |
| 2492 | if (ssh_packet_log_type(type)) |
| 2493 | debug3("%s: channel %u: down->up: type %u", __func__, |
| 2494 | downstream->self, type); |
| 2495 | |
| 2496 | switch (type) { |
| 2497 | case SSH2_MSG_CHANNEL_OPEN: |
| 2498 | if ((original = sshbuf_from(cp, have)) == NULL || |
| 2499 | (modified = sshbuf_new()) == NULL) { |
| 2500 | error("%s: alloc", __func__); |
| 2501 | goto out; |
| 2502 | } |
| 2503 | if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0 || |
| 2504 | (r = sshbuf_get_u32(original, &id)) != 0) { |
| 2505 | error("%s: parse error %s", __func__, ssh_err(r)); |
| 2506 | goto out; |
| 2507 | } |
| 2508 | c = channel_new("mux proxy", SSH_CHANNEL_MUX_PROXY, |
| 2509 | -1, -1, -1, 0, 0, 0, ctype, 1); |
| 2510 | c->mux_ctx = downstream; /* point to mux client */ |
| 2511 | c->mux_downstream_id = id; /* original downstream id */ |
| 2512 | if ((r = sshbuf_put_cstring(modified, ctype)) != 0 || |
| 2513 | (r = sshbuf_put_u32(modified, c->self)) != 0 || |
| 2514 | (r = sshbuf_putb(modified, original)) != 0) { |
| 2515 | error("%s: compose error %s", __func__, ssh_err(r)); |
| 2516 | channel_free(c); |
| 2517 | goto out; |
| 2518 | } |
| 2519 | break; |
| 2520 | case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION: |
| 2521 | /* |
| 2522 | * Almost the same as SSH2_MSG_CHANNEL_OPEN, except then we |
| 2523 | * need to parse 'remote_id' instead of 'ctype'. |
| 2524 | */ |
| 2525 | if ((original = sshbuf_from(cp, have)) == NULL || |
| 2526 | (modified = sshbuf_new()) == NULL) { |
| 2527 | error("%s: alloc", __func__); |
| 2528 | goto out; |
| 2529 | } |
| 2530 | if ((r = sshbuf_get_u32(original, &remote_id)) != 0 || |
| 2531 | (r = sshbuf_get_u32(original, &id)) != 0) { |
| 2532 | error("%s: parse error %s", __func__, ssh_err(r)); |
| 2533 | goto out; |
| 2534 | } |
| 2535 | c = channel_new("mux proxy", SSH_CHANNEL_MUX_PROXY, |
| 2536 | -1, -1, -1, 0, 0, 0, "mux-down-connect", 1); |
| 2537 | c->mux_ctx = downstream; /* point to mux client */ |
| 2538 | c->mux_downstream_id = id; |
| 2539 | c->remote_id = remote_id; |
| 2540 | if ((r = sshbuf_put_u32(modified, remote_id)) != 0 || |
| 2541 | (r = sshbuf_put_u32(modified, c->self)) != 0 || |
| 2542 | (r = sshbuf_putb(modified, original)) != 0) { |
| 2543 | error("%s: compose error %s", __func__, ssh_err(r)); |
| 2544 | channel_free(c); |
| 2545 | goto out; |
| 2546 | } |
| 2547 | break; |
| 2548 | case SSH2_MSG_GLOBAL_REQUEST: |
| 2549 | if ((original = sshbuf_from(cp, have)) == NULL) { |
| 2550 | error("%s: alloc", __func__); |
| 2551 | goto out; |
| 2552 | } |
| 2553 | if ((r = sshbuf_get_cstring(original, &ctype, NULL)) != 0) { |
| 2554 | error("%s: parse error %s", __func__, ssh_err(r)); |
| 2555 | goto out; |
| 2556 | } |
| 2557 | if (strcmp(ctype, "tcpip-forward") != 0) { |
| 2558 | error("%s: unsupported request %s", __func__, ctype); |
| 2559 | goto out; |
| 2560 | } |
| 2561 | if ((r = sshbuf_get_u8(original, NULL)) != 0 || |
| 2562 | (r = sshbuf_get_cstring(original, &listen_host, NULL)) != 0 || |
| 2563 | (r = sshbuf_get_u32(original, &listen_port)) != 0) { |
| 2564 | error("%s: parse error %s", __func__, ssh_err(r)); |
| 2565 | goto out; |
| 2566 | } |
| 2567 | if (listen_port > 65535) { |
| 2568 | error("%s: tcpip-forward for %s: bad port %u", |
| 2569 | __func__, listen_host, listen_port); |
| 2570 | goto out; |
| 2571 | } |
| 2572 | /* Record that connection to this host/port is permitted. */ |
| 2573 | permitted_opens = xreallocarray(permitted_opens, |
| 2574 | num_permitted_opens + 1, sizeof(*permitted_opens)); |
| 2575 | idx = num_permitted_opens++; |
| 2576 | permitted_opens[idx].host_to_connect = xstrdup("<mux>"); |
| 2577 | permitted_opens[idx].port_to_connect = -1; |
| 2578 | permitted_opens[idx].listen_host = listen_host; |
| 2579 | permitted_opens[idx].listen_port = (int)listen_port; |
| 2580 | permitted_opens[idx].downstream = downstream; |
| 2581 | listen_host = NULL; |
| 2582 | break; |
| 2583 | case SSH2_MSG_CHANNEL_CLOSE: |
| 2584 | if (have < 4) |
| 2585 | break; |
| 2586 | remote_id = PEEK_U32(cp); |
| 2587 | if ((c = channel_by_remote_id(remote_id)) != NULL) { |
| 2588 | if (c->flags & CHAN_CLOSE_RCVD) |
| 2589 | channel_free(c); |
| 2590 | else |
| 2591 | c->flags |= CHAN_CLOSE_SENT; |
| 2592 | } |
| 2593 | break; |
| 2594 | } |
| 2595 | if (modified) { |
| 2596 | if ((r = sshpkt_start(ssh, type)) != 0 || |
| 2597 | (r = sshpkt_putb(ssh, modified)) != 0 || |
| 2598 | (r = sshpkt_send(ssh)) != 0) { |
| 2599 | error("%s: send %s", __func__, ssh_err(r)); |
| 2600 | goto out; |
| 2601 | } |
| 2602 | } else { |
| 2603 | if ((r = sshpkt_start(ssh, type)) != 0 || |
| 2604 | (r = sshpkt_put(ssh, cp, have)) != 0 || |
| 2605 | (r = sshpkt_send(ssh)) != 0) { |
| 2606 | error("%s: send %s", __func__, ssh_err(r)); |
| 2607 | goto out; |
| 2608 | } |
| 2609 | } |
| 2610 | ret = 0; |
| 2611 | out: |
| 2612 | free(ctype); |
| 2613 | free(listen_host); |
| 2614 | sshbuf_free(original); |
| 2615 | sshbuf_free(modified); |
| 2616 | return ret; |
| 2617 | } |
| 2618 | |
| 2619 | /* |
| 2620 | * receive packets from upstream server and de-multiplex packets |
| 2621 | * to correct downstream: |
| 2622 | * implemented as a helper for channel input handlers, |
| 2623 | * replaces local (proxy) channel ID with downstream channel ID. |
| 2624 | */ |
| 2625 | int |
| 2626 | channel_proxy_upstream(Channel *c, int type, u_int32_t seq, void *ctxt) |
| 2627 | { |
| 2628 | struct ssh *ssh = active_state; |
| 2629 | struct sshbuf *b = NULL; |
| 2630 | Channel *downstream; |
| 2631 | const u_char *cp = NULL; |
| 2632 | size_t len; |
| 2633 | int r; |
| 2634 | |
| 2635 | /* |
| 2636 | * When receiving packets from the peer we need to check whether we |
| 2637 | * need to forward the packets to the mux client. In this case we |
| 2638 | * restore the orignal channel id and keep track of CLOSE messages, |
| 2639 | * so we can cleanup the channel. |
| 2640 | */ |
| 2641 | if (c == NULL || c->type != SSH_CHANNEL_MUX_PROXY) |
| 2642 | return 0; |
| 2643 | if ((downstream = c->mux_ctx) == NULL) |
| 2644 | return 0; |
| 2645 | switch (type) { |
| 2646 | case SSH2_MSG_CHANNEL_CLOSE: |
| 2647 | case SSH2_MSG_CHANNEL_DATA: |
| 2648 | case SSH2_MSG_CHANNEL_EOF: |
| 2649 | case SSH2_MSG_CHANNEL_EXTENDED_DATA: |
| 2650 | case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION: |
| 2651 | case SSH2_MSG_CHANNEL_OPEN_FAILURE: |
| 2652 | case SSH2_MSG_CHANNEL_WINDOW_ADJUST: |
| 2653 | case SSH2_MSG_CHANNEL_SUCCESS: |
| 2654 | case SSH2_MSG_CHANNEL_FAILURE: |
| 2655 | case SSH2_MSG_CHANNEL_REQUEST: |
| 2656 | break; |
| 2657 | default: |
| 2658 | debug2("%s: channel %u: unsupported type %u", __func__, |
| 2659 | c->self, type); |
| 2660 | return 0; |
| 2661 | } |
| 2662 | if ((b = sshbuf_new()) == NULL) { |
| 2663 | error("%s: alloc reply", __func__); |
| 2664 | goto out; |
| 2665 | } |
| 2666 | /* get remaining payload (after id) */ |
| 2667 | cp = sshpkt_ptr(ssh, &len); |
| 2668 | if (cp == NULL) { |
| 2669 | error("%s: no packet", __func__); |
| 2670 | goto out; |
| 2671 | } |
| 2672 | /* translate id and send to muxclient */ |
| 2673 | if ((r = sshbuf_put_u8(b, 0)) != 0 || /* padlen */ |
| 2674 | (r = sshbuf_put_u8(b, type)) != 0 || |
| 2675 | (r = sshbuf_put_u32(b, c->mux_downstream_id)) != 0 || |
| 2676 | (r = sshbuf_put(b, cp, len)) != 0 || |
| 2677 | (r = sshbuf_put_stringb(&downstream->output, b)) != 0) { |
| 2678 | error("%s: compose for muxclient %s", __func__, ssh_err(r)); |
| 2679 | goto out; |
| 2680 | } |
| 2681 | /* sshbuf_dump(b, stderr); */ |
| 2682 | if (ssh_packet_log_type(type)) |
| 2683 | debug3("%s: channel %u: up->down: type %u", __func__, c->self, |
| 2684 | type); |
| 2685 | out: |
| 2686 | /* update state */ |
| 2687 | switch (type) { |
| 2688 | case SSH2_MSG_CHANNEL_OPEN_CONFIRMATION: |
| 2689 | /* record remote_id for SSH2_MSG_CHANNEL_CLOSE */ |
| 2690 | if (cp && len > 4) |
| 2691 | c->remote_id = PEEK_U32(cp); |
| 2692 | break; |
| 2693 | case SSH2_MSG_CHANNEL_CLOSE: |
| 2694 | if (c->flags & CHAN_CLOSE_SENT) |
| 2695 | channel_free(c); |
| 2696 | else |
| 2697 | c->flags |= CHAN_CLOSE_RCVD; |
| 2698 | break; |
| 2699 | } |
| 2700 | sshbuf_free(b); |
| 2701 | return 1; |
| 2702 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2703 | |
| 2704 | /* -- protocol input */ |
| 2705 | |
| 2706 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2707 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2708 | channel_input_data(int type, u_int32_t seq, void *ctxt) |
| 2709 | { |
| 2710 | int id; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2711 | const u_char *data; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2712 | u_int data_len, win_len; |
| 2713 | Channel *c; |
| 2714 | |
| 2715 | /* Get the channel number and verify it. */ |
| 2716 | id = packet_get_int(); |
| 2717 | c = channel_lookup(id); |
| 2718 | if (c == NULL) |
| 2719 | packet_disconnect("Received data for nonexistent channel %d.", id); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2720 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2721 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2722 | |
| 2723 | /* Ignore any data for non-open channels (might happen on close) */ |
| 2724 | if (c->type != SSH_CHANNEL_OPEN && |
| 2725 | c->type != SSH_CHANNEL_X11_OPEN) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2726 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2727 | |
| 2728 | /* Get the data. */ |
| 2729 | data = packet_get_string_ptr(&data_len); |
| 2730 | win_len = data_len; |
| 2731 | if (c->datagram) |
| 2732 | win_len += 4; /* string length header */ |
| 2733 | |
| 2734 | /* |
| 2735 | * Ignore data for protocol > 1.3 if output end is no longer open. |
| 2736 | * For protocol 2 the sending side is reducing its window as it sends |
| 2737 | * data, so we must 'fake' consumption of the data in order to ensure |
| 2738 | * that window updates are sent back. Otherwise the connection might |
| 2739 | * deadlock. |
| 2740 | */ |
| 2741 | if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN) { |
| 2742 | if (compat20) { |
| 2743 | c->local_window -= win_len; |
| 2744 | c->local_consumed += win_len; |
| 2745 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2746 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2747 | } |
| 2748 | |
| 2749 | if (compat20) { |
| 2750 | if (win_len > c->local_maxpacket) { |
| 2751 | logit("channel %d: rcvd big packet %d, maxpack %d", |
| 2752 | c->self, win_len, c->local_maxpacket); |
| 2753 | } |
| 2754 | if (win_len > c->local_window) { |
| 2755 | logit("channel %d: rcvd too much data %d, win %d", |
| 2756 | c->self, win_len, c->local_window); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2757 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2758 | } |
| 2759 | c->local_window -= win_len; |
| 2760 | } |
| 2761 | if (c->datagram) |
| 2762 | buffer_put_string(&c->output, data, data_len); |
| 2763 | else |
| 2764 | buffer_append(&c->output, data, data_len); |
| 2765 | packet_check_eom(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2766 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2767 | } |
| 2768 | |
| 2769 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2770 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2771 | channel_input_extended_data(int type, u_int32_t seq, void *ctxt) |
| 2772 | { |
| 2773 | int id; |
| 2774 | char *data; |
| 2775 | u_int data_len, tcode; |
| 2776 | Channel *c; |
| 2777 | |
| 2778 | /* Get the channel number and verify it. */ |
| 2779 | id = packet_get_int(); |
| 2780 | c = channel_lookup(id); |
| 2781 | |
| 2782 | if (c == NULL) |
| 2783 | packet_disconnect("Received extended_data for bad channel %d.", id); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2784 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2785 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2786 | if (c->type != SSH_CHANNEL_OPEN) { |
| 2787 | logit("channel %d: ext data for non open", id); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2788 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2789 | } |
| 2790 | if (c->flags & CHAN_EOF_RCVD) { |
| 2791 | if (datafellows & SSH_BUG_EXTEOF) |
| 2792 | debug("channel %d: accepting ext data after eof", id); |
| 2793 | else |
| 2794 | packet_disconnect("Received extended_data after EOF " |
| 2795 | "on channel %d.", id); |
| 2796 | } |
| 2797 | tcode = packet_get_int(); |
| 2798 | if (c->efd == -1 || |
| 2799 | c->extended_usage != CHAN_EXTENDED_WRITE || |
| 2800 | tcode != SSH2_EXTENDED_DATA_STDERR) { |
| 2801 | logit("channel %d: bad ext data", c->self); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2802 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2803 | } |
| 2804 | data = packet_get_string(&data_len); |
| 2805 | packet_check_eom(); |
| 2806 | if (data_len > c->local_window) { |
| 2807 | logit("channel %d: rcvd too much extended_data %d, win %d", |
| 2808 | c->self, data_len, c->local_window); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2809 | free(data); |
| 2810 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2811 | } |
| 2812 | debug2("channel %d: rcvd ext data %d", c->self, data_len); |
| 2813 | c->local_window -= data_len; |
| 2814 | buffer_append(&c->extended, data, data_len); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2815 | free(data); |
| 2816 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2817 | } |
| 2818 | |
| 2819 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2820 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2821 | channel_input_ieof(int type, u_int32_t seq, void *ctxt) |
| 2822 | { |
| 2823 | int id; |
| 2824 | Channel *c; |
| 2825 | |
| 2826 | id = packet_get_int(); |
| 2827 | packet_check_eom(); |
| 2828 | c = channel_lookup(id); |
| 2829 | if (c == NULL) |
| 2830 | packet_disconnect("Received ieof for nonexistent channel %d.", id); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2831 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2832 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2833 | chan_rcvd_ieof(c); |
| 2834 | |
| 2835 | /* XXX force input close */ |
| 2836 | if (c->force_drain && c->istate == CHAN_INPUT_OPEN) { |
| 2837 | debug("channel %d: FORCE input drain", c->self); |
| 2838 | c->istate = CHAN_INPUT_WAIT_DRAIN; |
| 2839 | if (buffer_len(&c->input) == 0) |
| 2840 | chan_ibuf_empty(c); |
| 2841 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2842 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2843 | } |
| 2844 | |
| 2845 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2846 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2847 | channel_input_close(int type, u_int32_t seq, void *ctxt) |
| 2848 | { |
| 2849 | int id; |
| 2850 | Channel *c; |
| 2851 | |
| 2852 | id = packet_get_int(); |
| 2853 | packet_check_eom(); |
| 2854 | c = channel_lookup(id); |
| 2855 | if (c == NULL) |
| 2856 | packet_disconnect("Received close for nonexistent channel %d.", id); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2857 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2858 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2859 | /* |
| 2860 | * Send a confirmation that we have closed the channel and no more |
| 2861 | * data is coming for it. |
| 2862 | */ |
| 2863 | packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION); |
| 2864 | packet_put_int(c->remote_id); |
| 2865 | packet_send(); |
| 2866 | |
| 2867 | /* |
| 2868 | * If the channel is in closed state, we have sent a close request, |
| 2869 | * and the other side will eventually respond with a confirmation. |
| 2870 | * Thus, we cannot free the channel here, because then there would be |
| 2871 | * no-one to receive the confirmation. The channel gets freed when |
| 2872 | * the confirmation arrives. |
| 2873 | */ |
| 2874 | if (c->type != SSH_CHANNEL_CLOSED) { |
| 2875 | /* |
| 2876 | * Not a closed channel - mark it as draining, which will |
| 2877 | * cause it to be freed later. |
| 2878 | */ |
| 2879 | buffer_clear(&c->input); |
| 2880 | c->type = SSH_CHANNEL_OUTPUT_DRAINING; |
| 2881 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2882 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2883 | } |
| 2884 | |
| 2885 | /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */ |
| 2886 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2887 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2888 | channel_input_oclose(int type, u_int32_t seq, void *ctxt) |
| 2889 | { |
| 2890 | int id = packet_get_int(); |
| 2891 | Channel *c = channel_lookup(id); |
| 2892 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2893 | if (c == NULL) |
| 2894 | packet_disconnect("Received oclose for nonexistent channel %d.", id); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2895 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2896 | return 0; |
| 2897 | packet_check_eom(); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2898 | chan_rcvd_oclose(c); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2899 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2900 | } |
| 2901 | |
| 2902 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2903 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2904 | channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt) |
| 2905 | { |
| 2906 | int id = packet_get_int(); |
| 2907 | Channel *c = channel_lookup(id); |
| 2908 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2909 | if (c == NULL) |
| 2910 | packet_disconnect("Received close confirmation for " |
| 2911 | "out-of-range channel %d.", id); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2912 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2913 | return 0; |
| 2914 | packet_check_eom(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2915 | if (c->type != SSH_CHANNEL_CLOSED && c->type != SSH_CHANNEL_ABANDONED) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2916 | packet_disconnect("Received close confirmation for " |
| 2917 | "non-closed channel %d (type %d).", id, c->type); |
| 2918 | channel_free(c); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2919 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2920 | } |
| 2921 | |
| 2922 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2923 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2924 | channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt) |
| 2925 | { |
| 2926 | int id, remote_id; |
| 2927 | Channel *c; |
| 2928 | |
| 2929 | id = packet_get_int(); |
| 2930 | c = channel_lookup(id); |
| 2931 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2932 | if (c==NULL) |
| 2933 | packet_disconnect("Received open confirmation for " |
| 2934 | "unknown channel %d.", id); |
| 2935 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2936 | return 0; |
| 2937 | if (c->type != SSH_CHANNEL_OPENING) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2938 | packet_disconnect("Received open confirmation for " |
| 2939 | "non-opening channel %d.", id); |
| 2940 | remote_id = packet_get_int(); |
| 2941 | /* Record the remote channel number and mark that the channel is now open. */ |
| 2942 | c->remote_id = remote_id; |
| 2943 | c->type = SSH_CHANNEL_OPEN; |
| 2944 | |
| 2945 | if (compat20) { |
| 2946 | c->remote_window = packet_get_int(); |
| 2947 | c->remote_maxpacket = packet_get_int(); |
| 2948 | if (c->open_confirm) { |
| 2949 | debug2("callback start"); |
| 2950 | c->open_confirm(c->self, 1, c->open_confirm_ctx); |
| 2951 | debug2("callback done"); |
| 2952 | } |
| 2953 | debug2("channel %d: open confirm rwindow %u rmax %u", c->self, |
| 2954 | c->remote_window, c->remote_maxpacket); |
| 2955 | } |
| 2956 | packet_check_eom(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2957 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2958 | } |
| 2959 | |
| 2960 | static char * |
| 2961 | reason2txt(int reason) |
| 2962 | { |
| 2963 | switch (reason) { |
| 2964 | case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED: |
| 2965 | return "administratively prohibited"; |
| 2966 | case SSH2_OPEN_CONNECT_FAILED: |
| 2967 | return "connect failed"; |
| 2968 | case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE: |
| 2969 | return "unknown channel type"; |
| 2970 | case SSH2_OPEN_RESOURCE_SHORTAGE: |
| 2971 | return "resource shortage"; |
| 2972 | } |
| 2973 | return "unknown reason"; |
| 2974 | } |
| 2975 | |
| 2976 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 2977 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2978 | channel_input_open_failure(int type, u_int32_t seq, void *ctxt) |
| 2979 | { |
| 2980 | int id, reason; |
| 2981 | char *msg = NULL, *lang = NULL; |
| 2982 | Channel *c; |
| 2983 | |
| 2984 | id = packet_get_int(); |
| 2985 | c = channel_lookup(id); |
| 2986 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 2987 | if (c==NULL) |
| 2988 | packet_disconnect("Received open failure for " |
| 2989 | "unknown channel %d.", id); |
| 2990 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 2991 | return 0; |
| 2992 | if (c->type != SSH_CHANNEL_OPENING) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2993 | packet_disconnect("Received open failure for " |
| 2994 | "non-opening channel %d.", id); |
| 2995 | if (compat20) { |
| 2996 | reason = packet_get_int(); |
| 2997 | if (!(datafellows & SSH_BUG_OPENFAILURE)) { |
| 2998 | msg = packet_get_string(NULL); |
| 2999 | lang = packet_get_string(NULL); |
| 3000 | } |
| 3001 | logit("channel %d: open failed: %s%s%s", id, |
| 3002 | reason2txt(reason), msg ? ": ": "", msg ? msg : ""); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3003 | free(msg); |
| 3004 | free(lang); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3005 | if (c->open_confirm) { |
| 3006 | debug2("callback start"); |
| 3007 | c->open_confirm(c->self, 0, c->open_confirm_ctx); |
| 3008 | debug2("callback done"); |
| 3009 | } |
| 3010 | } |
| 3011 | packet_check_eom(); |
| 3012 | /* Schedule the channel for cleanup/deletion. */ |
| 3013 | chan_mark_dead(c); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3014 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3015 | } |
| 3016 | |
| 3017 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3018 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3019 | channel_input_window_adjust(int type, u_int32_t seq, void *ctxt) |
| 3020 | { |
| 3021 | Channel *c; |
| 3022 | int id; |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 3023 | u_int adjust, tmp; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3024 | |
| 3025 | if (!compat20) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3026 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3027 | |
| 3028 | /* Get the channel number and verify it. */ |
| 3029 | id = packet_get_int(); |
| 3030 | c = channel_lookup(id); |
| 3031 | |
| 3032 | if (c == NULL) { |
| 3033 | logit("Received window adjust for non-open channel %d.", id); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3034 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3035 | } |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3036 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 3037 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3038 | adjust = packet_get_int(); |
| 3039 | packet_check_eom(); |
| 3040 | debug2("channel %d: rcvd adjust %u", id, adjust); |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 3041 | if ((tmp = c->remote_window + adjust) < c->remote_window) |
| 3042 | fatal("channel %d: adjust %u overflows remote window %u", |
| 3043 | id, adjust, c->remote_window); |
| 3044 | c->remote_window = tmp; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3045 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3046 | } |
| 3047 | |
| 3048 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3049 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3050 | channel_input_port_open(int type, u_int32_t seq, void *ctxt) |
| 3051 | { |
| 3052 | Channel *c = NULL; |
| 3053 | u_short host_port; |
| 3054 | char *host, *originator_string; |
| 3055 | int remote_id; |
| 3056 | |
| 3057 | remote_id = packet_get_int(); |
| 3058 | host = packet_get_string(NULL); |
| 3059 | host_port = packet_get_int(); |
| 3060 | |
| 3061 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { |
| 3062 | originator_string = packet_get_string(NULL); |
| 3063 | } else { |
| 3064 | originator_string = xstrdup("unknown (remote did not supply name)"); |
| 3065 | } |
| 3066 | packet_check_eom(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3067 | c = channel_connect_to_port(host, host_port, |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3068 | "connected socket", originator_string, NULL, NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3069 | free(originator_string); |
| 3070 | free(host); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3071 | if (c == NULL) { |
| 3072 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
| 3073 | packet_put_int(remote_id); |
| 3074 | packet_send(); |
| 3075 | } else |
| 3076 | c->remote_id = remote_id; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3077 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3078 | } |
| 3079 | |
| 3080 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3081 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3082 | channel_input_status_confirm(int type, u_int32_t seq, void *ctxt) |
| 3083 | { |
| 3084 | Channel *c; |
| 3085 | struct channel_confirm *cc; |
| 3086 | int id; |
| 3087 | |
| 3088 | /* Reset keepalive timeout */ |
| 3089 | packet_set_alive_timeouts(0); |
| 3090 | |
| 3091 | id = packet_get_int(); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3092 | debug2("channel_input_status_confirm: type %d id %d", type, id); |
| 3093 | |
| 3094 | if ((c = channel_lookup(id)) == NULL) { |
| 3095 | logit("channel_input_status_confirm: %d: unknown", id); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3096 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3097 | } |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3098 | if (channel_proxy_upstream(c, type, seq, ctxt)) |
| 3099 | return 0; |
| 3100 | packet_check_eom(); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3101 | if ((cc = TAILQ_FIRST(&c->status_confirms)) == NULL) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3102 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3103 | cc->cb(type, c, cc->ctx); |
| 3104 | TAILQ_REMOVE(&c->status_confirms, cc, entry); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3105 | explicit_bzero(cc, sizeof(*cc)); |
| 3106 | free(cc); |
| 3107 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3108 | } |
| 3109 | |
| 3110 | /* -- tcp forwarding */ |
| 3111 | |
| 3112 | void |
| 3113 | channel_set_af(int af) |
| 3114 | { |
| 3115 | IPv4or6 = af; |
| 3116 | } |
| 3117 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3118 | |
| 3119 | /* |
| 3120 | * Determine whether or not a port forward listens to loopback, the |
| 3121 | * specified address or wildcard. On the client, a specified bind |
| 3122 | * address will always override gateway_ports. On the server, a |
| 3123 | * gateway_ports of 1 (``yes'') will override the client's specification |
| 3124 | * and force a wildcard bind, whereas a value of 2 (``clientspecified'') |
| 3125 | * will bind to whatever address the client asked for. |
| 3126 | * |
| 3127 | * Special-case listen_addrs are: |
| 3128 | * |
| 3129 | * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR |
| 3130 | * "" (empty string), "*" -> wildcard v4/v6 |
| 3131 | * "localhost" -> loopback v4/v6 |
| 3132 | * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set |
| 3133 | */ |
| 3134 | static const char * |
| 3135 | channel_fwd_bind_addr(const char *listen_addr, int *wildcardp, |
| 3136 | int is_client, struct ForwardOptions *fwd_opts) |
| 3137 | { |
| 3138 | const char *addr = NULL; |
| 3139 | int wildcard = 0; |
| 3140 | |
| 3141 | if (listen_addr == NULL) { |
| 3142 | /* No address specified: default to gateway_ports setting */ |
| 3143 | if (fwd_opts->gateway_ports) |
| 3144 | wildcard = 1; |
| 3145 | } else if (fwd_opts->gateway_ports || is_client) { |
| 3146 | if (((datafellows & SSH_OLD_FORWARD_ADDR) && |
| 3147 | strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) || |
| 3148 | *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 || |
| 3149 | (!is_client && fwd_opts->gateway_ports == 1)) { |
| 3150 | wildcard = 1; |
| 3151 | /* |
| 3152 | * Notify client if they requested a specific listen |
| 3153 | * address and it was overridden. |
| 3154 | */ |
| 3155 | if (*listen_addr != '\0' && |
| 3156 | strcmp(listen_addr, "0.0.0.0") != 0 && |
| 3157 | strcmp(listen_addr, "*") != 0) { |
| 3158 | packet_send_debug("Forwarding listen address " |
| 3159 | "\"%s\" overridden by server " |
| 3160 | "GatewayPorts", listen_addr); |
| 3161 | } |
| 3162 | } else if (strcmp(listen_addr, "localhost") != 0 || |
| 3163 | strcmp(listen_addr, "127.0.0.1") == 0 || |
| 3164 | strcmp(listen_addr, "::1") == 0) { |
| 3165 | /* Accept localhost address when GatewayPorts=yes */ |
| 3166 | addr = listen_addr; |
| 3167 | } |
| 3168 | } else if (strcmp(listen_addr, "127.0.0.1") == 0 || |
| 3169 | strcmp(listen_addr, "::1") == 0) { |
| 3170 | /* |
| 3171 | * If a specific IPv4/IPv6 localhost address has been |
| 3172 | * requested then accept it even if gateway_ports is in |
| 3173 | * effect. This allows the client to prefer IPv4 or IPv6. |
| 3174 | */ |
| 3175 | addr = listen_addr; |
| 3176 | } |
| 3177 | if (wildcardp != NULL) |
| 3178 | *wildcardp = wildcard; |
| 3179 | return addr; |
| 3180 | } |
| 3181 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3182 | static int |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3183 | channel_setup_fwd_listener_tcpip(int type, struct Forward *fwd, |
| 3184 | int *allocated_listen_port, struct ForwardOptions *fwd_opts) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3185 | { |
| 3186 | Channel *c; |
| 3187 | int sock, r, success = 0, wildcard = 0, is_client; |
| 3188 | struct addrinfo hints, *ai, *aitop; |
| 3189 | const char *host, *addr; |
| 3190 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
| 3191 | in_port_t *lport_p; |
| 3192 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3193 | is_client = (type == SSH_CHANNEL_PORT_LISTENER); |
| 3194 | |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 3195 | if (is_client && fwd->connect_path != NULL) { |
| 3196 | host = fwd->connect_path; |
| 3197 | } else { |
| 3198 | host = (type == SSH_CHANNEL_RPORT_LISTENER) ? |
| 3199 | fwd->listen_host : fwd->connect_host; |
| 3200 | if (host == NULL) { |
| 3201 | error("No forward host name."); |
| 3202 | return 0; |
| 3203 | } |
| 3204 | if (strlen(host) >= NI_MAXHOST) { |
| 3205 | error("Forward host name too long."); |
| 3206 | return 0; |
| 3207 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3208 | } |
| 3209 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3210 | /* Determine the bind address, cf. channel_fwd_bind_addr() comment */ |
| 3211 | addr = channel_fwd_bind_addr(fwd->listen_host, &wildcard, |
| 3212 | is_client, fwd_opts); |
| 3213 | debug3("%s: type %d wildcard %d addr %s", __func__, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3214 | type, wildcard, (addr == NULL) ? "NULL" : addr); |
| 3215 | |
| 3216 | /* |
| 3217 | * getaddrinfo returns a loopback address if the hostname is |
| 3218 | * set to NULL and hints.ai_flags is not AI_PASSIVE |
| 3219 | */ |
| 3220 | memset(&hints, 0, sizeof(hints)); |
| 3221 | hints.ai_family = IPv4or6; |
| 3222 | hints.ai_flags = wildcard ? AI_PASSIVE : 0; |
| 3223 | hints.ai_socktype = SOCK_STREAM; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3224 | snprintf(strport, sizeof strport, "%d", fwd->listen_port); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3225 | if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) { |
| 3226 | if (addr == NULL) { |
| 3227 | /* This really shouldn't happen */ |
| 3228 | packet_disconnect("getaddrinfo: fatal error: %s", |
| 3229 | ssh_gai_strerror(r)); |
| 3230 | } else { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3231 | error("%s: getaddrinfo(%.64s): %s", __func__, addr, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3232 | ssh_gai_strerror(r)); |
| 3233 | } |
| 3234 | return 0; |
| 3235 | } |
| 3236 | if (allocated_listen_port != NULL) |
| 3237 | *allocated_listen_port = 0; |
| 3238 | for (ai = aitop; ai; ai = ai->ai_next) { |
| 3239 | switch (ai->ai_family) { |
| 3240 | case AF_INET: |
| 3241 | lport_p = &((struct sockaddr_in *)ai->ai_addr)-> |
| 3242 | sin_port; |
| 3243 | break; |
| 3244 | case AF_INET6: |
| 3245 | lport_p = &((struct sockaddr_in6 *)ai->ai_addr)-> |
| 3246 | sin6_port; |
| 3247 | break; |
| 3248 | default: |
| 3249 | continue; |
| 3250 | } |
| 3251 | /* |
| 3252 | * If allocating a port for -R forwards, then use the |
| 3253 | * same port for all address families. |
| 3254 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3255 | if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 && |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3256 | allocated_listen_port != NULL && *allocated_listen_port > 0) |
| 3257 | *lport_p = htons(*allocated_listen_port); |
| 3258 | |
| 3259 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), |
| 3260 | strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3261 | error("%s: getnameinfo failed", __func__); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3262 | continue; |
| 3263 | } |
| 3264 | /* Create a port to listen for the host. */ |
| 3265 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
| 3266 | if (sock < 0) { |
| 3267 | /* this is no error since kernel may not support ipv6 */ |
| 3268 | verbose("socket: %.100s", strerror(errno)); |
| 3269 | continue; |
| 3270 | } |
| 3271 | |
| 3272 | channel_set_reuseaddr(sock); |
| 3273 | if (ai->ai_family == AF_INET6) |
| 3274 | sock_set_v6only(sock); |
| 3275 | |
| 3276 | debug("Local forwarding listening on %s port %s.", |
| 3277 | ntop, strport); |
| 3278 | |
| 3279 | /* Bind the socket to the address. */ |
| 3280 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { |
| 3281 | /* address can be in use ipv6 address is already bound */ |
| 3282 | if (!ai->ai_next) |
| 3283 | error("bind: %.100s", strerror(errno)); |
| 3284 | else |
| 3285 | verbose("bind: %.100s", strerror(errno)); |
| 3286 | |
| 3287 | close(sock); |
| 3288 | continue; |
| 3289 | } |
| 3290 | /* Start listening for connections on the socket. */ |
| 3291 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { |
| 3292 | error("listen: %.100s", strerror(errno)); |
| 3293 | close(sock); |
| 3294 | continue; |
| 3295 | } |
| 3296 | |
| 3297 | /* |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3298 | * fwd->listen_port == 0 requests a dynamically allocated port - |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3299 | * record what we got. |
| 3300 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3301 | if (type == SSH_CHANNEL_RPORT_LISTENER && fwd->listen_port == 0 && |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3302 | allocated_listen_port != NULL && |
| 3303 | *allocated_listen_port == 0) { |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3304 | *allocated_listen_port = get_local_port(sock); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3305 | debug("Allocated listen port %d", |
| 3306 | *allocated_listen_port); |
| 3307 | } |
| 3308 | |
| 3309 | /* Allocate a channel number for the socket. */ |
| 3310 | c = channel_new("port listener", type, sock, sock, -1, |
| 3311 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
| 3312 | 0, "port listener", 1); |
| 3313 | c->path = xstrdup(host); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3314 | c->host_port = fwd->connect_port; |
| 3315 | c->listening_addr = addr == NULL ? NULL : xstrdup(addr); |
| 3316 | if (fwd->listen_port == 0 && allocated_listen_port != NULL && |
| 3317 | !(datafellows & SSH_BUG_DYNAMIC_RPORT)) |
| 3318 | c->listening_port = *allocated_listen_port; |
| 3319 | else |
| 3320 | c->listening_port = fwd->listen_port; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3321 | success = 1; |
| 3322 | } |
| 3323 | if (success == 0) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3324 | error("%s: cannot listen to port: %d", __func__, |
| 3325 | fwd->listen_port); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3326 | freeaddrinfo(aitop); |
| 3327 | return success; |
| 3328 | } |
| 3329 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3330 | static int |
| 3331 | channel_setup_fwd_listener_streamlocal(int type, struct Forward *fwd, |
| 3332 | struct ForwardOptions *fwd_opts) |
| 3333 | { |
| 3334 | struct sockaddr_un sunaddr; |
| 3335 | const char *path; |
| 3336 | Channel *c; |
| 3337 | int port, sock; |
| 3338 | mode_t omask; |
| 3339 | |
| 3340 | switch (type) { |
| 3341 | case SSH_CHANNEL_UNIX_LISTENER: |
| 3342 | if (fwd->connect_path != NULL) { |
| 3343 | if (strlen(fwd->connect_path) > sizeof(sunaddr.sun_path)) { |
| 3344 | error("Local connecting path too long: %s", |
| 3345 | fwd->connect_path); |
| 3346 | return 0; |
| 3347 | } |
| 3348 | path = fwd->connect_path; |
| 3349 | port = PORT_STREAMLOCAL; |
| 3350 | } else { |
| 3351 | if (fwd->connect_host == NULL) { |
| 3352 | error("No forward host name."); |
| 3353 | return 0; |
| 3354 | } |
| 3355 | if (strlen(fwd->connect_host) >= NI_MAXHOST) { |
| 3356 | error("Forward host name too long."); |
| 3357 | return 0; |
| 3358 | } |
| 3359 | path = fwd->connect_host; |
| 3360 | port = fwd->connect_port; |
| 3361 | } |
| 3362 | break; |
| 3363 | case SSH_CHANNEL_RUNIX_LISTENER: |
| 3364 | path = fwd->listen_path; |
| 3365 | port = PORT_STREAMLOCAL; |
| 3366 | break; |
| 3367 | default: |
| 3368 | error("%s: unexpected channel type %d", __func__, type); |
| 3369 | return 0; |
| 3370 | } |
| 3371 | |
| 3372 | if (fwd->listen_path == NULL) { |
| 3373 | error("No forward path name."); |
| 3374 | return 0; |
| 3375 | } |
| 3376 | if (strlen(fwd->listen_path) > sizeof(sunaddr.sun_path)) { |
| 3377 | error("Local listening path too long: %s", fwd->listen_path); |
| 3378 | return 0; |
| 3379 | } |
| 3380 | |
| 3381 | debug3("%s: type %d path %s", __func__, type, fwd->listen_path); |
| 3382 | |
| 3383 | /* Start a Unix domain listener. */ |
| 3384 | omask = umask(fwd_opts->streamlocal_bind_mask); |
| 3385 | sock = unix_listener(fwd->listen_path, SSH_LISTEN_BACKLOG, |
| 3386 | fwd_opts->streamlocal_bind_unlink); |
| 3387 | umask(omask); |
| 3388 | if (sock < 0) |
| 3389 | return 0; |
| 3390 | |
| 3391 | debug("Local forwarding listening on path %s.", fwd->listen_path); |
| 3392 | |
| 3393 | /* Allocate a channel number for the socket. */ |
| 3394 | c = channel_new("unix listener", type, sock, sock, -1, |
| 3395 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, |
| 3396 | 0, "unix listener", 1); |
| 3397 | c->path = xstrdup(path); |
| 3398 | c->host_port = port; |
| 3399 | c->listening_port = PORT_STREAMLOCAL; |
| 3400 | c->listening_addr = xstrdup(fwd->listen_path); |
| 3401 | return 1; |
| 3402 | } |
| 3403 | |
| 3404 | static int |
| 3405 | channel_cancel_rport_listener_tcpip(const char *host, u_short port) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3406 | { |
| 3407 | u_int i; |
| 3408 | int found = 0; |
| 3409 | |
| 3410 | for (i = 0; i < channels_alloc; i++) { |
| 3411 | Channel *c = channels[i]; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3412 | if (c == NULL || c->type != SSH_CHANNEL_RPORT_LISTENER) |
| 3413 | continue; |
| 3414 | if (strcmp(c->path, host) == 0 && c->listening_port == port) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3415 | debug2("%s: close channel %d", __func__, i); |
| 3416 | channel_free(c); |
| 3417 | found = 1; |
| 3418 | } |
| 3419 | } |
| 3420 | |
| 3421 | return (found); |
| 3422 | } |
| 3423 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3424 | static int |
| 3425 | channel_cancel_rport_listener_streamlocal(const char *path) |
| 3426 | { |
| 3427 | u_int i; |
| 3428 | int found = 0; |
| 3429 | |
| 3430 | for (i = 0; i < channels_alloc; i++) { |
| 3431 | Channel *c = channels[i]; |
| 3432 | if (c == NULL || c->type != SSH_CHANNEL_RUNIX_LISTENER) |
| 3433 | continue; |
| 3434 | if (c->path == NULL) |
| 3435 | continue; |
| 3436 | if (strcmp(c->path, path) == 0) { |
| 3437 | debug2("%s: close channel %d", __func__, i); |
| 3438 | channel_free(c); |
| 3439 | found = 1; |
| 3440 | } |
| 3441 | } |
| 3442 | |
| 3443 | return (found); |
| 3444 | } |
| 3445 | |
| 3446 | int |
| 3447 | channel_cancel_rport_listener(struct Forward *fwd) |
| 3448 | { |
| 3449 | if (fwd->listen_path != NULL) |
| 3450 | return channel_cancel_rport_listener_streamlocal(fwd->listen_path); |
| 3451 | else |
| 3452 | return channel_cancel_rport_listener_tcpip(fwd->listen_host, fwd->listen_port); |
| 3453 | } |
| 3454 | |
| 3455 | static int |
| 3456 | channel_cancel_lport_listener_tcpip(const char *lhost, u_short lport, |
| 3457 | int cport, struct ForwardOptions *fwd_opts) |
| 3458 | { |
| 3459 | u_int i; |
| 3460 | int found = 0; |
| 3461 | const char *addr = channel_fwd_bind_addr(lhost, NULL, 1, fwd_opts); |
| 3462 | |
| 3463 | for (i = 0; i < channels_alloc; i++) { |
| 3464 | Channel *c = channels[i]; |
| 3465 | if (c == NULL || c->type != SSH_CHANNEL_PORT_LISTENER) |
| 3466 | continue; |
| 3467 | if (c->listening_port != lport) |
| 3468 | continue; |
| 3469 | if (cport == CHANNEL_CANCEL_PORT_STATIC) { |
| 3470 | /* skip dynamic forwardings */ |
| 3471 | if (c->host_port == 0) |
| 3472 | continue; |
| 3473 | } else { |
| 3474 | if (c->host_port != cport) |
| 3475 | continue; |
| 3476 | } |
| 3477 | if ((c->listening_addr == NULL && addr != NULL) || |
| 3478 | (c->listening_addr != NULL && addr == NULL)) |
| 3479 | continue; |
| 3480 | if (addr == NULL || strcmp(c->listening_addr, addr) == 0) { |
| 3481 | debug2("%s: close channel %d", __func__, i); |
| 3482 | channel_free(c); |
| 3483 | found = 1; |
| 3484 | } |
| 3485 | } |
| 3486 | |
| 3487 | return (found); |
| 3488 | } |
| 3489 | |
| 3490 | static int |
| 3491 | channel_cancel_lport_listener_streamlocal(const char *path) |
| 3492 | { |
| 3493 | u_int i; |
| 3494 | int found = 0; |
| 3495 | |
| 3496 | if (path == NULL) { |
| 3497 | error("%s: no path specified.", __func__); |
| 3498 | return 0; |
| 3499 | } |
| 3500 | |
| 3501 | for (i = 0; i < channels_alloc; i++) { |
| 3502 | Channel *c = channels[i]; |
| 3503 | if (c == NULL || c->type != SSH_CHANNEL_UNIX_LISTENER) |
| 3504 | continue; |
| 3505 | if (c->listening_addr == NULL) |
| 3506 | continue; |
| 3507 | if (strcmp(c->listening_addr, path) == 0) { |
| 3508 | debug2("%s: close channel %d", __func__, i); |
| 3509 | channel_free(c); |
| 3510 | found = 1; |
| 3511 | } |
| 3512 | } |
| 3513 | |
| 3514 | return (found); |
| 3515 | } |
| 3516 | |
| 3517 | int |
| 3518 | channel_cancel_lport_listener(struct Forward *fwd, int cport, struct ForwardOptions *fwd_opts) |
| 3519 | { |
| 3520 | if (fwd->listen_path != NULL) |
| 3521 | return channel_cancel_lport_listener_streamlocal(fwd->listen_path); |
| 3522 | else |
| 3523 | return channel_cancel_lport_listener_tcpip(fwd->listen_host, fwd->listen_port, cport, fwd_opts); |
| 3524 | } |
| 3525 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3526 | /* protocol local port fwd, used by ssh (and sshd in v1) */ |
| 3527 | int |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3528 | channel_setup_local_fwd_listener(struct Forward *fwd, struct ForwardOptions *fwd_opts) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3529 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3530 | if (fwd->listen_path != NULL) { |
| 3531 | return channel_setup_fwd_listener_streamlocal( |
| 3532 | SSH_CHANNEL_UNIX_LISTENER, fwd, fwd_opts); |
| 3533 | } else { |
| 3534 | return channel_setup_fwd_listener_tcpip(SSH_CHANNEL_PORT_LISTENER, |
| 3535 | fwd, NULL, fwd_opts); |
| 3536 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3537 | } |
| 3538 | |
| 3539 | /* protocol v2 remote port fwd, used by sshd */ |
| 3540 | int |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3541 | channel_setup_remote_fwd_listener(struct Forward *fwd, |
| 3542 | int *allocated_listen_port, struct ForwardOptions *fwd_opts) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3543 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3544 | if (fwd->listen_path != NULL) { |
| 3545 | return channel_setup_fwd_listener_streamlocal( |
| 3546 | SSH_CHANNEL_RUNIX_LISTENER, fwd, fwd_opts); |
| 3547 | } else { |
| 3548 | return channel_setup_fwd_listener_tcpip( |
| 3549 | SSH_CHANNEL_RPORT_LISTENER, fwd, allocated_listen_port, |
| 3550 | fwd_opts); |
| 3551 | } |
| 3552 | } |
| 3553 | |
| 3554 | /* |
| 3555 | * Translate the requested rfwd listen host to something usable for |
| 3556 | * this server. |
| 3557 | */ |
| 3558 | static const char * |
| 3559 | channel_rfwd_bind_host(const char *listen_host) |
| 3560 | { |
| 3561 | if (listen_host == NULL) { |
| 3562 | if (datafellows & SSH_BUG_RFWD_ADDR) |
| 3563 | return "127.0.0.1"; |
| 3564 | else |
| 3565 | return "localhost"; |
| 3566 | } else if (*listen_host == '\0' || strcmp(listen_host, "*") == 0) { |
| 3567 | if (datafellows & SSH_BUG_RFWD_ADDR) |
| 3568 | return "0.0.0.0"; |
| 3569 | else |
| 3570 | return ""; |
| 3571 | } else |
| 3572 | return listen_host; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3573 | } |
| 3574 | |
| 3575 | /* |
| 3576 | * Initiate forwarding of connections to port "port" on remote host through |
| 3577 | * the secure channel to host:port from local side. |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3578 | * Returns handle (index) for updating the dynamic listen port with |
| 3579 | * channel_update_permitted_opens(). |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3580 | */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3581 | int |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3582 | channel_request_remote_forwarding(struct Forward *fwd) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3583 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3584 | int type, success = 0, idx = -1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3585 | |
| 3586 | /* Send the forward request to the remote side. */ |
| 3587 | if (compat20) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3588 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3589 | if (fwd->listen_path != NULL) { |
| 3590 | packet_put_cstring("streamlocal-forward@openssh.com"); |
| 3591 | packet_put_char(1); /* boolean: want reply */ |
| 3592 | packet_put_cstring(fwd->listen_path); |
| 3593 | } else { |
| 3594 | packet_put_cstring("tcpip-forward"); |
| 3595 | packet_put_char(1); /* boolean: want reply */ |
| 3596 | packet_put_cstring(channel_rfwd_bind_host(fwd->listen_host)); |
| 3597 | packet_put_int(fwd->listen_port); |
| 3598 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3599 | packet_send(); |
| 3600 | packet_write_wait(); |
| 3601 | /* Assume that server accepts the request */ |
| 3602 | success = 1; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3603 | } else if (fwd->listen_path == NULL) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3604 | packet_start(SSH_CMSG_PORT_FORWARD_REQUEST); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3605 | packet_put_int(fwd->listen_port); |
| 3606 | packet_put_cstring(fwd->connect_host); |
| 3607 | packet_put_int(fwd->connect_port); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3608 | packet_send(); |
| 3609 | packet_write_wait(); |
| 3610 | |
| 3611 | /* Wait for response from the remote side. */ |
| 3612 | type = packet_read(); |
| 3613 | switch (type) { |
| 3614 | case SSH_SMSG_SUCCESS: |
| 3615 | success = 1; |
| 3616 | break; |
| 3617 | case SSH_SMSG_FAILURE: |
| 3618 | break; |
| 3619 | default: |
| 3620 | /* Unknown packet */ |
| 3621 | packet_disconnect("Protocol error for port forward request:" |
| 3622 | "received packet type %d.", type); |
| 3623 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3624 | } else { |
| 3625 | logit("Warning: Server does not support remote stream local forwarding."); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3626 | } |
| 3627 | if (success) { |
| 3628 | /* Record that connection to this host/port is permitted. */ |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 3629 | permitted_opens = xreallocarray(permitted_opens, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3630 | num_permitted_opens + 1, sizeof(*permitted_opens)); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3631 | idx = num_permitted_opens++; |
| 3632 | if (fwd->connect_path != NULL) { |
| 3633 | permitted_opens[idx].host_to_connect = |
| 3634 | xstrdup(fwd->connect_path); |
| 3635 | permitted_opens[idx].port_to_connect = |
| 3636 | PORT_STREAMLOCAL; |
| 3637 | } else { |
| 3638 | permitted_opens[idx].host_to_connect = |
| 3639 | xstrdup(fwd->connect_host); |
| 3640 | permitted_opens[idx].port_to_connect = |
| 3641 | fwd->connect_port; |
| 3642 | } |
| 3643 | if (fwd->listen_path != NULL) { |
| 3644 | permitted_opens[idx].listen_host = NULL; |
| 3645 | permitted_opens[idx].listen_path = |
| 3646 | xstrdup(fwd->listen_path); |
| 3647 | permitted_opens[idx].listen_port = PORT_STREAMLOCAL; |
| 3648 | } else { |
| 3649 | permitted_opens[idx].listen_host = |
| 3650 | fwd->listen_host ? xstrdup(fwd->listen_host) : NULL; |
| 3651 | permitted_opens[idx].listen_path = NULL; |
| 3652 | permitted_opens[idx].listen_port = fwd->listen_port; |
| 3653 | } |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3654 | permitted_opens[idx].downstream = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3655 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3656 | return (idx); |
| 3657 | } |
| 3658 | |
| 3659 | static int |
| 3660 | open_match(ForwardPermission *allowed_open, const char *requestedhost, |
| 3661 | int requestedport) |
| 3662 | { |
| 3663 | if (allowed_open->host_to_connect == NULL) |
| 3664 | return 0; |
| 3665 | if (allowed_open->port_to_connect != FWD_PERMIT_ANY_PORT && |
| 3666 | allowed_open->port_to_connect != requestedport) |
| 3667 | return 0; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3668 | if (strcmp(allowed_open->host_to_connect, FWD_PERMIT_ANY_HOST) != 0 && |
| 3669 | strcmp(allowed_open->host_to_connect, requestedhost) != 0) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3670 | return 0; |
| 3671 | return 1; |
| 3672 | } |
| 3673 | |
| 3674 | /* |
| 3675 | * Note that in the listen host/port case |
| 3676 | * we don't support FWD_PERMIT_ANY_PORT and |
| 3677 | * need to translate between the configured-host (listen_host) |
| 3678 | * and what we've sent to the remote server (channel_rfwd_bind_host) |
| 3679 | */ |
| 3680 | static int |
| 3681 | open_listen_match_tcpip(ForwardPermission *allowed_open, |
| 3682 | const char *requestedhost, u_short requestedport, int translate) |
| 3683 | { |
| 3684 | const char *allowed_host; |
| 3685 | |
| 3686 | if (allowed_open->host_to_connect == NULL) |
| 3687 | return 0; |
| 3688 | if (allowed_open->listen_port != requestedport) |
| 3689 | return 0; |
| 3690 | if (!translate && allowed_open->listen_host == NULL && |
| 3691 | requestedhost == NULL) |
| 3692 | return 1; |
| 3693 | allowed_host = translate ? |
| 3694 | channel_rfwd_bind_host(allowed_open->listen_host) : |
| 3695 | allowed_open->listen_host; |
| 3696 | if (allowed_host == NULL || |
| 3697 | strcmp(allowed_host, requestedhost) != 0) |
| 3698 | return 0; |
| 3699 | return 1; |
| 3700 | } |
| 3701 | |
| 3702 | static int |
| 3703 | open_listen_match_streamlocal(ForwardPermission *allowed_open, |
| 3704 | const char *requestedpath) |
| 3705 | { |
| 3706 | if (allowed_open->host_to_connect == NULL) |
| 3707 | return 0; |
| 3708 | if (allowed_open->listen_port != PORT_STREAMLOCAL) |
| 3709 | return 0; |
| 3710 | if (allowed_open->listen_path == NULL || |
| 3711 | strcmp(allowed_open->listen_path, requestedpath) != 0) |
| 3712 | return 0; |
| 3713 | return 1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3714 | } |
| 3715 | |
| 3716 | /* |
| 3717 | * Request cancellation of remote forwarding of connection host:port from |
| 3718 | * local side. |
| 3719 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3720 | static int |
| 3721 | channel_request_rforward_cancel_tcpip(const char *host, u_short port) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3722 | { |
| 3723 | int i; |
| 3724 | |
| 3725 | if (!compat20) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3726 | return -1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3727 | |
| 3728 | for (i = 0; i < num_permitted_opens; i++) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3729 | if (open_listen_match_tcpip(&permitted_opens[i], host, port, 0)) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3730 | break; |
| 3731 | } |
| 3732 | if (i >= num_permitted_opens) { |
| 3733 | debug("%s: requested forward not found", __func__); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3734 | return -1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3735 | } |
| 3736 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
| 3737 | packet_put_cstring("cancel-tcpip-forward"); |
| 3738 | packet_put_char(0); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3739 | packet_put_cstring(channel_rfwd_bind_host(host)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3740 | packet_put_int(port); |
| 3741 | packet_send(); |
| 3742 | |
| 3743 | permitted_opens[i].listen_port = 0; |
| 3744 | permitted_opens[i].port_to_connect = 0; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3745 | free(permitted_opens[i].host_to_connect); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3746 | permitted_opens[i].host_to_connect = NULL; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3747 | free(permitted_opens[i].listen_host); |
| 3748 | permitted_opens[i].listen_host = NULL; |
| 3749 | permitted_opens[i].listen_path = NULL; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3750 | permitted_opens[i].downstream = NULL; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3751 | |
| 3752 | return 0; |
| 3753 | } |
| 3754 | |
| 3755 | /* |
| 3756 | * Request cancellation of remote forwarding of Unix domain socket |
| 3757 | * path from local side. |
| 3758 | */ |
| 3759 | static int |
| 3760 | channel_request_rforward_cancel_streamlocal(const char *path) |
| 3761 | { |
| 3762 | int i; |
| 3763 | |
| 3764 | if (!compat20) |
| 3765 | return -1; |
| 3766 | |
| 3767 | for (i = 0; i < num_permitted_opens; i++) { |
| 3768 | if (open_listen_match_streamlocal(&permitted_opens[i], path)) |
| 3769 | break; |
| 3770 | } |
| 3771 | if (i >= num_permitted_opens) { |
| 3772 | debug("%s: requested forward not found", __func__); |
| 3773 | return -1; |
| 3774 | } |
| 3775 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
| 3776 | packet_put_cstring("cancel-streamlocal-forward@openssh.com"); |
| 3777 | packet_put_char(0); |
| 3778 | packet_put_cstring(path); |
| 3779 | packet_send(); |
| 3780 | |
| 3781 | permitted_opens[i].listen_port = 0; |
| 3782 | permitted_opens[i].port_to_connect = 0; |
| 3783 | free(permitted_opens[i].host_to_connect); |
| 3784 | permitted_opens[i].host_to_connect = NULL; |
| 3785 | permitted_opens[i].listen_host = NULL; |
| 3786 | free(permitted_opens[i].listen_path); |
| 3787 | permitted_opens[i].listen_path = NULL; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3788 | permitted_opens[i].downstream = NULL; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3789 | |
| 3790 | return 0; |
| 3791 | } |
| 3792 | |
| 3793 | /* |
| 3794 | * Request cancellation of remote forwarding of a connection from local side. |
| 3795 | */ |
| 3796 | int |
| 3797 | channel_request_rforward_cancel(struct Forward *fwd) |
| 3798 | { |
| 3799 | if (fwd->listen_path != NULL) { |
| 3800 | return (channel_request_rforward_cancel_streamlocal( |
| 3801 | fwd->listen_path)); |
| 3802 | } else { |
| 3803 | return (channel_request_rforward_cancel_tcpip(fwd->listen_host, |
| 3804 | fwd->listen_port ? fwd->listen_port : fwd->allocated_port)); |
| 3805 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3806 | } |
| 3807 | |
| 3808 | /* |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3809 | * Permits opening to any host/port if permitted_opens[] is empty. This is |
| 3810 | * usually called by the server, because the user could connect to any port |
| 3811 | * anyway, and the server has no way to know but to trust the client anyway. |
| 3812 | */ |
| 3813 | void |
| 3814 | channel_permit_all_opens(void) |
| 3815 | { |
| 3816 | if (num_permitted_opens == 0) |
| 3817 | all_opens_permitted = 1; |
| 3818 | } |
| 3819 | |
| 3820 | void |
| 3821 | channel_add_permitted_opens(char *host, int port) |
| 3822 | { |
| 3823 | debug("allow port forwarding to host %s port %d", host, port); |
| 3824 | |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 3825 | permitted_opens = xreallocarray(permitted_opens, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3826 | num_permitted_opens + 1, sizeof(*permitted_opens)); |
| 3827 | permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host); |
| 3828 | permitted_opens[num_permitted_opens].port_to_connect = port; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3829 | permitted_opens[num_permitted_opens].listen_host = NULL; |
| 3830 | permitted_opens[num_permitted_opens].listen_path = NULL; |
| 3831 | permitted_opens[num_permitted_opens].listen_port = 0; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3832 | permitted_opens[num_permitted_opens].downstream = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3833 | num_permitted_opens++; |
| 3834 | |
| 3835 | all_opens_permitted = 0; |
| 3836 | } |
| 3837 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3838 | /* |
| 3839 | * Update the listen port for a dynamic remote forward, after |
| 3840 | * the actual 'newport' has been allocated. If 'newport' < 0 is |
| 3841 | * passed then they entry will be invalidated. |
| 3842 | */ |
| 3843 | void |
| 3844 | channel_update_permitted_opens(int idx, int newport) |
| 3845 | { |
| 3846 | if (idx < 0 || idx >= num_permitted_opens) { |
| 3847 | debug("channel_update_permitted_opens: index out of range:" |
| 3848 | " %d num_permitted_opens %d", idx, num_permitted_opens); |
| 3849 | return; |
| 3850 | } |
| 3851 | debug("%s allowed port %d for forwarding to host %s port %d", |
| 3852 | newport > 0 ? "Updating" : "Removing", |
| 3853 | newport, |
| 3854 | permitted_opens[idx].host_to_connect, |
| 3855 | permitted_opens[idx].port_to_connect); |
| 3856 | if (newport >= 0) { |
| 3857 | permitted_opens[idx].listen_port = |
| 3858 | (datafellows & SSH_BUG_DYNAMIC_RPORT) ? 0 : newport; |
| 3859 | } else { |
| 3860 | permitted_opens[idx].listen_port = 0; |
| 3861 | permitted_opens[idx].port_to_connect = 0; |
| 3862 | free(permitted_opens[idx].host_to_connect); |
| 3863 | permitted_opens[idx].host_to_connect = NULL; |
| 3864 | free(permitted_opens[idx].listen_host); |
| 3865 | permitted_opens[idx].listen_host = NULL; |
| 3866 | free(permitted_opens[idx].listen_path); |
| 3867 | permitted_opens[idx].listen_path = NULL; |
| 3868 | } |
| 3869 | } |
| 3870 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3871 | int |
| 3872 | channel_add_adm_permitted_opens(char *host, int port) |
| 3873 | { |
| 3874 | debug("config allows port forwarding to host %s port %d", host, port); |
| 3875 | |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 3876 | permitted_adm_opens = xreallocarray(permitted_adm_opens, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3877 | num_adm_permitted_opens + 1, sizeof(*permitted_adm_opens)); |
| 3878 | permitted_adm_opens[num_adm_permitted_opens].host_to_connect |
| 3879 | = xstrdup(host); |
| 3880 | permitted_adm_opens[num_adm_permitted_opens].port_to_connect = port; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3881 | permitted_adm_opens[num_adm_permitted_opens].listen_host = NULL; |
| 3882 | permitted_adm_opens[num_adm_permitted_opens].listen_path = NULL; |
| 3883 | permitted_adm_opens[num_adm_permitted_opens].listen_port = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3884 | return ++num_adm_permitted_opens; |
| 3885 | } |
| 3886 | |
| 3887 | void |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3888 | channel_disable_adm_local_opens(void) |
| 3889 | { |
| 3890 | channel_clear_adm_permitted_opens(); |
Greg Hartman | ccacbc9 | 2016-02-03 09:59:44 -0800 | [diff] [blame] | 3891 | permitted_adm_opens = xcalloc(sizeof(*permitted_adm_opens), 1); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3892 | permitted_adm_opens[num_adm_permitted_opens].host_to_connect = NULL; |
| 3893 | num_adm_permitted_opens = 1; |
| 3894 | } |
| 3895 | |
| 3896 | void |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3897 | channel_clear_permitted_opens(void) |
| 3898 | { |
| 3899 | int i; |
| 3900 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3901 | for (i = 0; i < num_permitted_opens; i++) { |
| 3902 | free(permitted_opens[i].host_to_connect); |
| 3903 | free(permitted_opens[i].listen_host); |
| 3904 | free(permitted_opens[i].listen_path); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3905 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3906 | free(permitted_opens); |
| 3907 | permitted_opens = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3908 | num_permitted_opens = 0; |
| 3909 | } |
| 3910 | |
| 3911 | void |
| 3912 | channel_clear_adm_permitted_opens(void) |
| 3913 | { |
| 3914 | int i; |
| 3915 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3916 | for (i = 0; i < num_adm_permitted_opens; i++) { |
| 3917 | free(permitted_adm_opens[i].host_to_connect); |
| 3918 | free(permitted_adm_opens[i].listen_host); |
| 3919 | free(permitted_adm_opens[i].listen_path); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3920 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3921 | free(permitted_adm_opens); |
| 3922 | permitted_adm_opens = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3923 | num_adm_permitted_opens = 0; |
| 3924 | } |
| 3925 | |
| 3926 | void |
| 3927 | channel_print_adm_permitted_opens(void) |
| 3928 | { |
| 3929 | int i; |
| 3930 | |
| 3931 | printf("permitopen"); |
| 3932 | if (num_adm_permitted_opens == 0) { |
| 3933 | printf(" any\n"); |
| 3934 | return; |
| 3935 | } |
| 3936 | for (i = 0; i < num_adm_permitted_opens; i++) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3937 | if (permitted_adm_opens[i].host_to_connect == NULL) |
| 3938 | printf(" none"); |
| 3939 | else |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3940 | printf(" %s:%d", permitted_adm_opens[i].host_to_connect, |
| 3941 | permitted_adm_opens[i].port_to_connect); |
| 3942 | printf("\n"); |
| 3943 | } |
| 3944 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3945 | /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */ |
| 3946 | int |
| 3947 | permitopen_port(const char *p) |
| 3948 | { |
| 3949 | int port; |
| 3950 | |
| 3951 | if (strcmp(p, "*") == 0) |
| 3952 | return FWD_PERMIT_ANY_PORT; |
| 3953 | if ((port = a2port(p)) > 0) |
| 3954 | return port; |
| 3955 | return -1; |
| 3956 | } |
| 3957 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3958 | /* Try to start non-blocking connect to next host in cctx list */ |
| 3959 | static int |
| 3960 | connect_next(struct channel_connect *cctx) |
| 3961 | { |
| 3962 | int sock, saved_errno; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3963 | struct sockaddr_un *sunaddr; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 3964 | char ntop[NI_MAXHOST], strport[MAXIMUM(NI_MAXSERV,sizeof(sunaddr->sun_path))]; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3965 | |
| 3966 | for (; cctx->ai; cctx->ai = cctx->ai->ai_next) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 3967 | switch (cctx->ai->ai_family) { |
| 3968 | case AF_UNIX: |
| 3969 | /* unix:pathname instead of host:port */ |
| 3970 | sunaddr = (struct sockaddr_un *)cctx->ai->ai_addr; |
| 3971 | strlcpy(ntop, "unix", sizeof(ntop)); |
| 3972 | strlcpy(strport, sunaddr->sun_path, sizeof(strport)); |
| 3973 | break; |
| 3974 | case AF_INET: |
| 3975 | case AF_INET6: |
| 3976 | if (getnameinfo(cctx->ai->ai_addr, cctx->ai->ai_addrlen, |
| 3977 | ntop, sizeof(ntop), strport, sizeof(strport), |
| 3978 | NI_NUMERICHOST|NI_NUMERICSERV) != 0) { |
| 3979 | error("connect_next: getnameinfo failed"); |
| 3980 | continue; |
| 3981 | } |
| 3982 | break; |
| 3983 | default: |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 3984 | continue; |
| 3985 | } |
| 3986 | if ((sock = socket(cctx->ai->ai_family, cctx->ai->ai_socktype, |
| 3987 | cctx->ai->ai_protocol)) == -1) { |
| 3988 | if (cctx->ai->ai_next == NULL) |
| 3989 | error("socket: %.100s", strerror(errno)); |
| 3990 | else |
| 3991 | verbose("socket: %.100s", strerror(errno)); |
| 3992 | continue; |
| 3993 | } |
| 3994 | if (set_nonblock(sock) == -1) |
| 3995 | fatal("%s: set_nonblock(%d)", __func__, sock); |
| 3996 | if (connect(sock, cctx->ai->ai_addr, |
| 3997 | cctx->ai->ai_addrlen) == -1 && errno != EINPROGRESS) { |
| 3998 | debug("connect_next: host %.100s ([%.100s]:%s): " |
| 3999 | "%.100s", cctx->host, ntop, strport, |
| 4000 | strerror(errno)); |
| 4001 | saved_errno = errno; |
| 4002 | close(sock); |
| 4003 | errno = saved_errno; |
| 4004 | continue; /* fail -- try next */ |
| 4005 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4006 | if (cctx->ai->ai_family != AF_UNIX) |
| 4007 | set_nodelay(sock); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4008 | debug("connect_next: host %.100s ([%.100s]:%s) " |
| 4009 | "in progress, fd=%d", cctx->host, ntop, strport, sock); |
| 4010 | cctx->ai = cctx->ai->ai_next; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4011 | return sock; |
| 4012 | } |
| 4013 | return -1; |
| 4014 | } |
| 4015 | |
| 4016 | static void |
| 4017 | channel_connect_ctx_free(struct channel_connect *cctx) |
| 4018 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4019 | free(cctx->host); |
| 4020 | if (cctx->aitop) { |
| 4021 | if (cctx->aitop->ai_family == AF_UNIX) |
| 4022 | free(cctx->aitop); |
| 4023 | else |
| 4024 | freeaddrinfo(cctx->aitop); |
| 4025 | } |
| 4026 | memset(cctx, 0, sizeof(*cctx)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4027 | } |
| 4028 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4029 | /* |
| 4030 | * Return CONNECTING channel to remote host:port or local socket path, |
| 4031 | * passing back the failure reason if appropriate. |
| 4032 | */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4033 | static Channel * |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4034 | connect_to_reason(const char *name, int port, char *ctype, char *rname, |
| 4035 | int *reason, const char **errmsg) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4036 | { |
| 4037 | struct addrinfo hints; |
| 4038 | int gaierr; |
| 4039 | int sock = -1; |
| 4040 | char strport[NI_MAXSERV]; |
| 4041 | struct channel_connect cctx; |
| 4042 | Channel *c; |
| 4043 | |
| 4044 | memset(&cctx, 0, sizeof(cctx)); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4045 | |
| 4046 | if (port == PORT_STREAMLOCAL) { |
| 4047 | struct sockaddr_un *sunaddr; |
| 4048 | struct addrinfo *ai; |
| 4049 | |
| 4050 | if (strlen(name) > sizeof(sunaddr->sun_path)) { |
| 4051 | error("%.100s: %.100s", name, strerror(ENAMETOOLONG)); |
| 4052 | return (NULL); |
| 4053 | } |
| 4054 | |
| 4055 | /* |
| 4056 | * Fake up a struct addrinfo for AF_UNIX connections. |
| 4057 | * channel_connect_ctx_free() must check ai_family |
| 4058 | * and use free() not freeaddirinfo() for AF_UNIX. |
| 4059 | */ |
| 4060 | ai = xmalloc(sizeof(*ai) + sizeof(*sunaddr)); |
| 4061 | memset(ai, 0, sizeof(*ai) + sizeof(*sunaddr)); |
| 4062 | ai->ai_addr = (struct sockaddr *)(ai + 1); |
| 4063 | ai->ai_addrlen = sizeof(*sunaddr); |
| 4064 | ai->ai_family = AF_UNIX; |
| 4065 | ai->ai_socktype = SOCK_STREAM; |
| 4066 | ai->ai_protocol = PF_UNSPEC; |
| 4067 | sunaddr = (struct sockaddr_un *)ai->ai_addr; |
| 4068 | sunaddr->sun_family = AF_UNIX; |
| 4069 | strlcpy(sunaddr->sun_path, name, sizeof(sunaddr->sun_path)); |
| 4070 | cctx.aitop = ai; |
| 4071 | } else { |
| 4072 | memset(&hints, 0, sizeof(hints)); |
| 4073 | hints.ai_family = IPv4or6; |
| 4074 | hints.ai_socktype = SOCK_STREAM; |
| 4075 | snprintf(strport, sizeof strport, "%d", port); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4076 | if ((gaierr = getaddrinfo(name, strport, &hints, &cctx.aitop)) |
| 4077 | != 0) { |
| 4078 | if (errmsg != NULL) |
| 4079 | *errmsg = ssh_gai_strerror(gaierr); |
| 4080 | if (reason != NULL) |
| 4081 | *reason = SSH2_OPEN_CONNECT_FAILED; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4082 | error("connect_to %.100s: unknown host (%s)", name, |
| 4083 | ssh_gai_strerror(gaierr)); |
| 4084 | return NULL; |
| 4085 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4086 | } |
| 4087 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4088 | cctx.host = xstrdup(name); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4089 | cctx.port = port; |
| 4090 | cctx.ai = cctx.aitop; |
| 4091 | |
| 4092 | if ((sock = connect_next(&cctx)) == -1) { |
| 4093 | error("connect to %.100s port %d failed: %s", |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4094 | name, port, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4095 | channel_connect_ctx_free(&cctx); |
| 4096 | return NULL; |
| 4097 | } |
| 4098 | c = channel_new(ctype, SSH_CHANNEL_CONNECTING, sock, sock, -1, |
| 4099 | CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, rname, 1); |
| 4100 | c->connect_ctx = cctx; |
| 4101 | return c; |
| 4102 | } |
| 4103 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4104 | /* Return CONNECTING channel to remote host:port or local socket path */ |
| 4105 | static Channel * |
| 4106 | connect_to(const char *name, int port, char *ctype, char *rname) |
| 4107 | { |
| 4108 | return connect_to_reason(name, port, ctype, rname, NULL, NULL); |
| 4109 | } |
| 4110 | |
| 4111 | /* |
| 4112 | * returns either the newly connected channel or the downstream channel |
| 4113 | * that needs to deal with this connection. |
| 4114 | */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4115 | Channel * |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4116 | channel_connect_by_listen_address(const char *listen_host, |
| 4117 | u_short listen_port, char *ctype, char *rname) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4118 | { |
| 4119 | int i; |
| 4120 | |
| 4121 | for (i = 0; i < num_permitted_opens; i++) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4122 | if (open_listen_match_tcpip(&permitted_opens[i], listen_host, |
| 4123 | listen_port, 1)) { |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4124 | if (permitted_opens[i].downstream) |
| 4125 | return permitted_opens[i].downstream; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4126 | return connect_to( |
| 4127 | permitted_opens[i].host_to_connect, |
| 4128 | permitted_opens[i].port_to_connect, ctype, rname); |
| 4129 | } |
| 4130 | } |
| 4131 | error("WARNING: Server requests forwarding for unknown listen_port %d", |
| 4132 | listen_port); |
| 4133 | return NULL; |
| 4134 | } |
| 4135 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4136 | Channel * |
| 4137 | channel_connect_by_listen_path(const char *path, char *ctype, char *rname) |
| 4138 | { |
| 4139 | int i; |
| 4140 | |
| 4141 | for (i = 0; i < num_permitted_opens; i++) { |
| 4142 | if (open_listen_match_streamlocal(&permitted_opens[i], path)) { |
| 4143 | return connect_to( |
| 4144 | permitted_opens[i].host_to_connect, |
| 4145 | permitted_opens[i].port_to_connect, ctype, rname); |
| 4146 | } |
| 4147 | } |
| 4148 | error("WARNING: Server requests forwarding for unknown path %.100s", |
| 4149 | path); |
| 4150 | return NULL; |
| 4151 | } |
| 4152 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4153 | /* Check if connecting to that port is permitted and connect. */ |
| 4154 | Channel * |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4155 | channel_connect_to_port(const char *host, u_short port, char *ctype, |
| 4156 | char *rname, int *reason, const char **errmsg) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4157 | { |
| 4158 | int i, permit, permit_adm = 1; |
| 4159 | |
| 4160 | permit = all_opens_permitted; |
| 4161 | if (!permit) { |
| 4162 | for (i = 0; i < num_permitted_opens; i++) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4163 | if (open_match(&permitted_opens[i], host, port)) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4164 | permit = 1; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4165 | break; |
| 4166 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4167 | } |
| 4168 | |
| 4169 | if (num_adm_permitted_opens > 0) { |
| 4170 | permit_adm = 0; |
| 4171 | for (i = 0; i < num_adm_permitted_opens; i++) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4172 | if (open_match(&permitted_adm_opens[i], host, port)) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4173 | permit_adm = 1; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4174 | break; |
| 4175 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4176 | } |
| 4177 | |
| 4178 | if (!permit || !permit_adm) { |
| 4179 | logit("Received request to connect to host %.100s port %d, " |
| 4180 | "but the request was denied.", host, port); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4181 | if (reason != NULL) |
| 4182 | *reason = SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4183 | return NULL; |
| 4184 | } |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4185 | return connect_to_reason(host, port, ctype, rname, reason, errmsg); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4186 | } |
| 4187 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4188 | /* Check if connecting to that path is permitted and connect. */ |
| 4189 | Channel * |
| 4190 | channel_connect_to_path(const char *path, char *ctype, char *rname) |
| 4191 | { |
| 4192 | int i, permit, permit_adm = 1; |
| 4193 | |
| 4194 | permit = all_opens_permitted; |
| 4195 | if (!permit) { |
| 4196 | for (i = 0; i < num_permitted_opens; i++) |
| 4197 | if (open_match(&permitted_opens[i], path, PORT_STREAMLOCAL)) { |
| 4198 | permit = 1; |
| 4199 | break; |
| 4200 | } |
| 4201 | } |
| 4202 | |
| 4203 | if (num_adm_permitted_opens > 0) { |
| 4204 | permit_adm = 0; |
| 4205 | for (i = 0; i < num_adm_permitted_opens; i++) |
| 4206 | if (open_match(&permitted_adm_opens[i], path, PORT_STREAMLOCAL)) { |
| 4207 | permit_adm = 1; |
| 4208 | break; |
| 4209 | } |
| 4210 | } |
| 4211 | |
| 4212 | if (!permit || !permit_adm) { |
| 4213 | logit("Received request to connect to path %.100s, " |
| 4214 | "but the request was denied.", path); |
| 4215 | return NULL; |
| 4216 | } |
| 4217 | return connect_to(path, PORT_STREAMLOCAL, ctype, rname); |
| 4218 | } |
| 4219 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4220 | void |
| 4221 | channel_send_window_changes(void) |
| 4222 | { |
| 4223 | u_int i; |
| 4224 | struct winsize ws; |
| 4225 | |
| 4226 | for (i = 0; i < channels_alloc; i++) { |
| 4227 | if (channels[i] == NULL || !channels[i]->client_tty || |
| 4228 | channels[i]->type != SSH_CHANNEL_OPEN) |
| 4229 | continue; |
| 4230 | if (ioctl(channels[i]->rfd, TIOCGWINSZ, &ws) < 0) |
| 4231 | continue; |
| 4232 | channel_request_start(i, "window-change", 0); |
| 4233 | packet_put_int((u_int)ws.ws_col); |
| 4234 | packet_put_int((u_int)ws.ws_row); |
| 4235 | packet_put_int((u_int)ws.ws_xpixel); |
| 4236 | packet_put_int((u_int)ws.ws_ypixel); |
| 4237 | packet_send(); |
| 4238 | } |
| 4239 | } |
| 4240 | |
| 4241 | /* -- X11 forwarding */ |
| 4242 | |
| 4243 | /* |
| 4244 | * Creates an internet domain socket for listening for X11 connections. |
| 4245 | * Returns 0 and a suitable display number for the DISPLAY variable |
| 4246 | * stored in display_numberp , or -1 if an error occurs. |
| 4247 | */ |
| 4248 | int |
| 4249 | x11_create_display_inet(int x11_display_offset, int x11_use_localhost, |
| 4250 | int single_connection, u_int *display_numberp, int **chanids) |
| 4251 | { |
| 4252 | Channel *nc = NULL; |
| 4253 | int display_number, sock; |
| 4254 | u_short port; |
| 4255 | struct addrinfo hints, *ai, *aitop; |
| 4256 | char strport[NI_MAXSERV]; |
| 4257 | int gaierr, n, num_socks = 0, socks[NUM_SOCKS]; |
| 4258 | |
| 4259 | if (chanids == NULL) |
| 4260 | return -1; |
| 4261 | |
| 4262 | for (display_number = x11_display_offset; |
| 4263 | display_number < MAX_DISPLAYS; |
| 4264 | display_number++) { |
| 4265 | port = 6000 + display_number; |
| 4266 | memset(&hints, 0, sizeof(hints)); |
| 4267 | hints.ai_family = IPv4or6; |
| 4268 | hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE; |
| 4269 | hints.ai_socktype = SOCK_STREAM; |
| 4270 | snprintf(strport, sizeof strport, "%d", port); |
| 4271 | if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) { |
| 4272 | error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr)); |
| 4273 | return -1; |
| 4274 | } |
| 4275 | for (ai = aitop; ai; ai = ai->ai_next) { |
| 4276 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) |
| 4277 | continue; |
| 4278 | sock = socket(ai->ai_family, ai->ai_socktype, |
| 4279 | ai->ai_protocol); |
| 4280 | if (sock < 0) { |
| 4281 | if ((errno != EINVAL) && (errno != EAFNOSUPPORT) |
| 4282 | #ifdef EPFNOSUPPORT |
| 4283 | && (errno != EPFNOSUPPORT) |
| 4284 | #endif |
| 4285 | ) { |
| 4286 | error("socket: %.100s", strerror(errno)); |
| 4287 | freeaddrinfo(aitop); |
| 4288 | return -1; |
| 4289 | } else { |
| 4290 | debug("x11_create_display_inet: Socket family %d not supported", |
| 4291 | ai->ai_family); |
| 4292 | continue; |
| 4293 | } |
| 4294 | } |
| 4295 | if (ai->ai_family == AF_INET6) |
| 4296 | sock_set_v6only(sock); |
| 4297 | if (x11_use_localhost) |
| 4298 | channel_set_reuseaddr(sock); |
| 4299 | if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) { |
| 4300 | debug2("bind port %d: %.100s", port, strerror(errno)); |
| 4301 | close(sock); |
| 4302 | |
| 4303 | for (n = 0; n < num_socks; n++) { |
| 4304 | close(socks[n]); |
| 4305 | } |
| 4306 | num_socks = 0; |
| 4307 | break; |
| 4308 | } |
| 4309 | socks[num_socks++] = sock; |
| 4310 | if (num_socks == NUM_SOCKS) |
| 4311 | break; |
| 4312 | } |
| 4313 | freeaddrinfo(aitop); |
| 4314 | if (num_socks > 0) |
| 4315 | break; |
| 4316 | } |
| 4317 | if (display_number >= MAX_DISPLAYS) { |
| 4318 | error("Failed to allocate internet-domain X11 display socket."); |
| 4319 | return -1; |
| 4320 | } |
| 4321 | /* Start listening for connections on the socket. */ |
| 4322 | for (n = 0; n < num_socks; n++) { |
| 4323 | sock = socks[n]; |
| 4324 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { |
| 4325 | error("listen: %.100s", strerror(errno)); |
| 4326 | close(sock); |
| 4327 | return -1; |
| 4328 | } |
| 4329 | } |
| 4330 | |
| 4331 | /* Allocate a channel for each socket. */ |
| 4332 | *chanids = xcalloc(num_socks + 1, sizeof(**chanids)); |
| 4333 | for (n = 0; n < num_socks; n++) { |
| 4334 | sock = socks[n]; |
| 4335 | nc = channel_new("x11 listener", |
| 4336 | SSH_CHANNEL_X11_LISTENER, sock, sock, -1, |
| 4337 | CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, |
| 4338 | 0, "X11 inet listener", 1); |
| 4339 | nc->single_connection = single_connection; |
| 4340 | (*chanids)[n] = nc->self; |
| 4341 | } |
| 4342 | (*chanids)[n] = -1; |
| 4343 | |
| 4344 | /* Return the display number for the DISPLAY environment variable. */ |
| 4345 | *display_numberp = display_number; |
| 4346 | return (0); |
| 4347 | } |
| 4348 | |
| 4349 | static int |
| 4350 | connect_local_xsocket_path(const char *pathname) |
| 4351 | { |
| 4352 | int sock; |
| 4353 | struct sockaddr_un addr; |
| 4354 | |
| 4355 | sock = socket(AF_UNIX, SOCK_STREAM, 0); |
| 4356 | if (sock < 0) |
| 4357 | error("socket: %.100s", strerror(errno)); |
| 4358 | memset(&addr, 0, sizeof(addr)); |
| 4359 | addr.sun_family = AF_UNIX; |
| 4360 | strlcpy(addr.sun_path, pathname, sizeof addr.sun_path); |
| 4361 | if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0) |
| 4362 | return sock; |
| 4363 | close(sock); |
| 4364 | error("connect %.100s: %.100s", addr.sun_path, strerror(errno)); |
| 4365 | return -1; |
| 4366 | } |
| 4367 | |
| 4368 | static int |
| 4369 | connect_local_xsocket(u_int dnr) |
| 4370 | { |
| 4371 | char buf[1024]; |
| 4372 | snprintf(buf, sizeof buf, _PATH_UNIX_X, dnr); |
| 4373 | return connect_local_xsocket_path(buf); |
| 4374 | } |
| 4375 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4376 | #ifdef __APPLE__ |
| 4377 | static int |
| 4378 | is_path_to_xsocket(const char *display, char *path, size_t pathlen) |
| 4379 | { |
| 4380 | struct stat sbuf; |
| 4381 | |
| 4382 | if (strlcpy(path, display, pathlen) >= pathlen) { |
| 4383 | error("%s: display path too long", __func__); |
| 4384 | return 0; |
| 4385 | } |
| 4386 | if (display[0] != '/') |
| 4387 | return 0; |
| 4388 | if (stat(path, &sbuf) == 0) { |
| 4389 | return 1; |
| 4390 | } else { |
| 4391 | char *dot = strrchr(path, '.'); |
| 4392 | if (dot != NULL) { |
| 4393 | *dot = '\0'; |
| 4394 | if (stat(path, &sbuf) == 0) { |
| 4395 | return 1; |
| 4396 | } |
| 4397 | } |
| 4398 | } |
| 4399 | return 0; |
| 4400 | } |
| 4401 | #endif |
| 4402 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4403 | int |
| 4404 | x11_connect_display(void) |
| 4405 | { |
| 4406 | u_int display_number; |
| 4407 | const char *display; |
| 4408 | char buf[1024], *cp; |
| 4409 | struct addrinfo hints, *ai, *aitop; |
| 4410 | char strport[NI_MAXSERV]; |
| 4411 | int gaierr, sock = 0; |
| 4412 | |
| 4413 | /* Try to open a socket for the local X server. */ |
| 4414 | display = getenv("DISPLAY"); |
| 4415 | if (!display) { |
| 4416 | error("DISPLAY not set."); |
| 4417 | return -1; |
| 4418 | } |
| 4419 | /* |
| 4420 | * Now we decode the value of the DISPLAY variable and make a |
| 4421 | * connection to the real X server. |
| 4422 | */ |
| 4423 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4424 | #ifdef __APPLE__ |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4425 | /* Check if display is a path to a socket (as set by launchd). */ |
| 4426 | { |
| 4427 | char path[PATH_MAX]; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4428 | |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4429 | if (is_path_to_xsocket(display, path, sizeof(path))) { |
| 4430 | debug("x11_connect_display: $DISPLAY is launchd"); |
| 4431 | |
| 4432 | /* Create a socket. */ |
| 4433 | sock = connect_local_xsocket_path(path); |
| 4434 | if (sock < 0) |
| 4435 | return -1; |
| 4436 | |
| 4437 | /* OK, we now have a connection to the display. */ |
| 4438 | return sock; |
| 4439 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4440 | } |
| 4441 | #endif |
| 4442 | /* |
| 4443 | * Check if it is a unix domain socket. Unix domain displays are in |
| 4444 | * one of the following formats: unix:d[.s], :d[.s], ::d[.s] |
| 4445 | */ |
| 4446 | if (strncmp(display, "unix:", 5) == 0 || |
| 4447 | display[0] == ':') { |
| 4448 | /* Connect to the unix domain socket. */ |
| 4449 | if (sscanf(strrchr(display, ':') + 1, "%u", &display_number) != 1) { |
| 4450 | error("Could not parse display number from DISPLAY: %.100s", |
| 4451 | display); |
| 4452 | return -1; |
| 4453 | } |
| 4454 | /* Create a socket. */ |
| 4455 | sock = connect_local_xsocket(display_number); |
| 4456 | if (sock < 0) |
| 4457 | return -1; |
| 4458 | |
| 4459 | /* OK, we now have a connection to the display. */ |
| 4460 | return sock; |
| 4461 | } |
| 4462 | /* |
| 4463 | * Connect to an inet socket. The DISPLAY value is supposedly |
| 4464 | * hostname:d[.s], where hostname may also be numeric IP address. |
| 4465 | */ |
| 4466 | strlcpy(buf, display, sizeof(buf)); |
| 4467 | cp = strchr(buf, ':'); |
| 4468 | if (!cp) { |
| 4469 | error("Could not find ':' in DISPLAY: %.100s", display); |
| 4470 | return -1; |
| 4471 | } |
| 4472 | *cp = 0; |
| 4473 | /* buf now contains the host name. But first we parse the display number. */ |
| 4474 | if (sscanf(cp + 1, "%u", &display_number) != 1) { |
| 4475 | error("Could not parse display number from DISPLAY: %.100s", |
| 4476 | display); |
| 4477 | return -1; |
| 4478 | } |
| 4479 | |
| 4480 | /* Look up the host address */ |
| 4481 | memset(&hints, 0, sizeof(hints)); |
| 4482 | hints.ai_family = IPv4or6; |
| 4483 | hints.ai_socktype = SOCK_STREAM; |
| 4484 | snprintf(strport, sizeof strport, "%u", 6000 + display_number); |
| 4485 | if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) { |
| 4486 | error("%.100s: unknown host. (%s)", buf, |
| 4487 | ssh_gai_strerror(gaierr)); |
| 4488 | return -1; |
| 4489 | } |
| 4490 | for (ai = aitop; ai; ai = ai->ai_next) { |
| 4491 | /* Create a socket. */ |
| 4492 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
| 4493 | if (sock < 0) { |
| 4494 | debug2("socket: %.100s", strerror(errno)); |
| 4495 | continue; |
| 4496 | } |
| 4497 | /* Connect it to the display. */ |
| 4498 | if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) { |
| 4499 | debug2("connect %.100s port %u: %.100s", buf, |
| 4500 | 6000 + display_number, strerror(errno)); |
| 4501 | close(sock); |
| 4502 | continue; |
| 4503 | } |
| 4504 | /* Success */ |
| 4505 | break; |
| 4506 | } |
| 4507 | freeaddrinfo(aitop); |
| 4508 | if (!ai) { |
| 4509 | error("connect %.100s port %u: %.100s", buf, 6000 + display_number, |
| 4510 | strerror(errno)); |
| 4511 | return -1; |
| 4512 | } |
| 4513 | set_nodelay(sock); |
| 4514 | return sock; |
| 4515 | } |
| 4516 | |
| 4517 | /* |
| 4518 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains |
| 4519 | * the remote channel number. We should do whatever we want, and respond |
| 4520 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. |
| 4521 | */ |
| 4522 | |
| 4523 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4524 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4525 | x11_input_open(int type, u_int32_t seq, void *ctxt) |
| 4526 | { |
| 4527 | Channel *c = NULL; |
| 4528 | int remote_id, sock = 0; |
| 4529 | char *remote_host; |
| 4530 | |
| 4531 | debug("Received X11 open request."); |
| 4532 | |
| 4533 | remote_id = packet_get_int(); |
| 4534 | |
| 4535 | if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) { |
| 4536 | remote_host = packet_get_string(NULL); |
| 4537 | } else { |
| 4538 | remote_host = xstrdup("unknown (remote did not supply name)"); |
| 4539 | } |
| 4540 | packet_check_eom(); |
| 4541 | |
| 4542 | /* Obtain a connection to the real X display. */ |
| 4543 | sock = x11_connect_display(); |
| 4544 | if (sock != -1) { |
| 4545 | /* Allocate a channel for this connection. */ |
| 4546 | c = channel_new("connected x11 socket", |
| 4547 | SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0, |
| 4548 | remote_host, 1); |
| 4549 | c->remote_id = remote_id; |
| 4550 | c->force_drain = 1; |
| 4551 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4552 | free(remote_host); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4553 | if (c == NULL) { |
| 4554 | /* Send refusal to the remote host. */ |
| 4555 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
| 4556 | packet_put_int(remote_id); |
| 4557 | } else { |
| 4558 | /* Send a confirmation to the remote host. */ |
| 4559 | packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION); |
| 4560 | packet_put_int(remote_id); |
| 4561 | packet_put_int(c->self); |
| 4562 | } |
| 4563 | packet_send(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4564 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4565 | } |
| 4566 | |
| 4567 | /* dummy protocol handler that denies SSH-1 requests (agent/x11) */ |
| 4568 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4569 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4570 | deny_input_open(int type, u_int32_t seq, void *ctxt) |
| 4571 | { |
| 4572 | int rchan = packet_get_int(); |
| 4573 | |
| 4574 | switch (type) { |
| 4575 | case SSH_SMSG_AGENT_OPEN: |
| 4576 | error("Warning: ssh server tried agent forwarding."); |
| 4577 | break; |
| 4578 | case SSH_SMSG_X11_OPEN: |
| 4579 | error("Warning: ssh server tried X11 forwarding."); |
| 4580 | break; |
| 4581 | default: |
| 4582 | error("deny_input_open: type %d", type); |
| 4583 | break; |
| 4584 | } |
| 4585 | error("Warning: this is probably a break-in attempt by a malicious server."); |
| 4586 | packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE); |
| 4587 | packet_put_int(rchan); |
| 4588 | packet_send(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4589 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4590 | } |
| 4591 | |
| 4592 | /* |
| 4593 | * Requests forwarding of X11 connections, generates fake authentication |
| 4594 | * data, and enables authentication spoofing. |
| 4595 | * This should be called in the client only. |
| 4596 | */ |
| 4597 | void |
| 4598 | x11_request_forwarding_with_spoofing(int client_session_id, const char *disp, |
| 4599 | const char *proto, const char *data, int want_reply) |
| 4600 | { |
| 4601 | u_int data_len = (u_int) strlen(data) / 2; |
| 4602 | u_int i, value; |
| 4603 | char *new_data; |
| 4604 | int screen_number; |
| 4605 | const char *cp; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4606 | |
| 4607 | if (x11_saved_display == NULL) |
| 4608 | x11_saved_display = xstrdup(disp); |
| 4609 | else if (strcmp(disp, x11_saved_display) != 0) { |
| 4610 | error("x11_request_forwarding_with_spoofing: different " |
| 4611 | "$DISPLAY already forwarded"); |
| 4612 | return; |
| 4613 | } |
| 4614 | |
| 4615 | cp = strchr(disp, ':'); |
| 4616 | if (cp) |
| 4617 | cp = strchr(cp, '.'); |
| 4618 | if (cp) |
| 4619 | screen_number = (u_int)strtonum(cp + 1, 0, 400, NULL); |
| 4620 | else |
| 4621 | screen_number = 0; |
| 4622 | |
| 4623 | if (x11_saved_proto == NULL) { |
| 4624 | /* Save protocol name. */ |
| 4625 | x11_saved_proto = xstrdup(proto); |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4626 | |
| 4627 | /* Extract real authentication data. */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4628 | x11_saved_data = xmalloc(data_len); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4629 | for (i = 0; i < data_len; i++) { |
| 4630 | if (sscanf(data + 2 * i, "%2x", &value) != 1) |
| 4631 | fatal("x11_request_forwarding: bad " |
| 4632 | "authentication data: %.100s", data); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4633 | x11_saved_data[i] = value; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4634 | } |
| 4635 | x11_saved_data_len = data_len; |
Greg Hartman | 9768ca4 | 2017-06-22 20:49:52 -0700 | [diff] [blame] | 4636 | |
| 4637 | /* Generate fake data of the same length. */ |
| 4638 | x11_fake_data = xmalloc(data_len); |
| 4639 | arc4random_buf(x11_fake_data, data_len); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4640 | x11_fake_data_len = data_len; |
| 4641 | } |
| 4642 | |
| 4643 | /* Convert the fake data into hex. */ |
| 4644 | new_data = tohex(x11_fake_data, data_len); |
| 4645 | |
| 4646 | /* Send the request packet. */ |
| 4647 | if (compat20) { |
| 4648 | channel_request_start(client_session_id, "x11-req", want_reply); |
| 4649 | packet_put_char(0); /* XXX bool single connection */ |
| 4650 | } else { |
| 4651 | packet_start(SSH_CMSG_X11_REQUEST_FORWARDING); |
| 4652 | } |
| 4653 | packet_put_cstring(proto); |
| 4654 | packet_put_cstring(new_data); |
| 4655 | packet_put_int(screen_number); |
| 4656 | packet_send(); |
| 4657 | packet_write_wait(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 4658 | free(new_data); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 4659 | } |
| 4660 | |
| 4661 | |
| 4662 | /* -- agent forwarding */ |
| 4663 | |
| 4664 | /* Sends a message to the server to request authentication fd forwarding. */ |
| 4665 | |
| 4666 | void |
| 4667 | auth_request_forwarding(void) |
| 4668 | { |
| 4669 | packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING); |
| 4670 | packet_send(); |
| 4671 | packet_write_wait(); |
| 4672 | } |