| File: | src/usr.sbin/npppd/npppd/../l2tp/l2tp_ctrl.c |
| Warning: | line 134, column 2 Value stored to 'i' is never read |
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| 1 | /* $OpenBSD: l2tp_ctrl.c,v 1.26 2021/05/22 08:29:57 yasuoka Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 2009 Internet Initiative Japan Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| 17 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 20 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 21 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 22 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 23 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 24 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 25 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 26 | * SUCH DAMAGE. |
| 27 | */ |
| 28 | /**@file Control connection processing functions for L2TP LNS */ |
| 29 | /* $Id: l2tp_ctrl.c,v 1.26 2021/05/22 08:29:57 yasuoka Exp $ */ |
| 30 | #include <sys/types.h> |
| 31 | #include <sys/time.h> |
| 32 | #include <sys/socket.h> |
| 33 | #include <netinet/in.h> |
| 34 | #include <net/if.h> |
| 35 | #include <arpa/inet.h> |
| 36 | #include <endian.h> |
| 37 | #include <errno(*__errno()).h> |
| 38 | #include <event.h> |
| 39 | #include <netdb.h> |
| 40 | #include <stdarg.h> |
| 41 | #include <stddef.h> |
| 42 | #include <stdio.h> |
| 43 | #include <stdlib.h> |
| 44 | #include <string.h> |
| 45 | #include <syslog.h> |
| 46 | #include <time.h> |
| 47 | #include <unistd.h> |
| 48 | #include <limits.h> |
| 49 | |
| 50 | #ifdef USE_LIBSOCKUTIL |
| 51 | #include <seil/sockfromto.h> |
| 52 | #endif |
| 53 | |
| 54 | #include "time_utils.h" |
| 55 | #include "bytebuf.h" |
| 56 | #include "hash.h" |
| 57 | #include "debugutil.h" |
| 58 | #include "slist.h" |
| 59 | #include "l2tp.h" |
| 60 | #include "l2tp_local.h" |
| 61 | #include "l2tp_subr.h" |
| 62 | #include "net_utils.h" |
| 63 | #include "version.h" |
| 64 | #include "recvfromto.h" |
| 65 | |
| 66 | #define MINIMUM(a, b)(((a) < (b)) ? (a) : (b)) (((a) < (b)) ? (a) : (b)) |
| 67 | |
| 68 | static int l2tp_ctrl_init(l2tp_ctrl *, l2tpd *, struct sockaddr *, struct sockaddr *, void *); |
| 69 | static void l2tp_ctrl_reload(l2tp_ctrl *); |
| 70 | static int l2tp_ctrl_send_disconnect_notify(l2tp_ctrl *); |
| 71 | static void l2tp_ctrl_timeout(int, short, void *); |
| 72 | static int l2tp_ctrl_resend_una_packets(l2tp_ctrl *, bool_Bool); |
| 73 | static void l2tp_ctrl_destroy_all_calls(l2tp_ctrl *); |
| 74 | static int l2tp_ctrl_disconnect_all_calls(l2tp_ctrl *, int); |
| 75 | static void l2tp_ctrl_reset_timeout(l2tp_ctrl *); |
| 76 | static int l2tp_ctrl_txwin_size(l2tp_ctrl *); |
| 77 | static bool_Bool l2tp_ctrl_txwin_is_full(l2tp_ctrl *); |
| 78 | static bool_Bool l2tp_ctrl_in_peer_window(l2tp_ctrl *, uint16_t); |
| 79 | static bool_Bool l2tp_ctrl_in_our_window(l2tp_ctrl *, uint16_t); |
| 80 | static int l2tp_ctrl_recv_SCCRQ(l2tp_ctrl *, u_char *, int, l2tpd *, struct sockaddr *); |
| 81 | static int l2tp_ctrl_send_StopCCN(l2tp_ctrl *, int); |
| 82 | static int l2tp_ctrl_recv_StopCCN(l2tp_ctrl *, u_char *, int); |
| 83 | static void l2tp_ctrl_send_SCCRP(l2tp_ctrl *); |
| 84 | static int l2tp_ctrl_send_HELLO(l2tp_ctrl *); |
| 85 | static int l2tp_ctrl_send_ZLB(l2tp_ctrl *); |
| 86 | static const char *l2tp_ctrl_state_string(l2tp_ctrl *); |
| 87 | |
| 88 | #ifdef L2TP_CTRL_DEBUG |
| 89 | #define L2TP_CTRL_ASSERT(x) ASSERT(x)((void)0); |
| 90 | #define L2TP_CTRL_DBG(x) l2tp_ctrl_log x |
| 91 | #else |
| 92 | #define L2TP_CTRL_ASSERT(x) |
| 93 | #define L2TP_CTRL_DBG(x) |
| 94 | #endif |
| 95 | |
| 96 | /* Sequence # of l2tp_ctrl ID */ |
| 97 | static u_int l2tp_ctrl_id_seq = 0; |
| 98 | |
| 99 | #define SEQ_LT(a,b)((int16_t)((a) - (b)) < 0) ((int16_t)((a) - (b)) < 0) |
| 100 | #define SEQ_GT(a,b)((int16_t)((a) - (b)) > 0) ((int16_t)((a) - (b)) > 0) |
| 101 | |
| 102 | /** |
| 103 | * Build instance of {@link ::_l2tp_ctrl L2TP LNS control connection} |
| 104 | */ |
| 105 | l2tp_ctrl * |
| 106 | l2tp_ctrl_create(void) |
| 107 | { |
| 108 | |
| 109 | return calloc(1, sizeof(l2tp_ctrl)); |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | * initialize and startup of {@link ::_l2tp_ctrl L2TP LNS control connection} |
| 114 | * instance |
| 115 | */ |
| 116 | static int |
| 117 | l2tp_ctrl_init(l2tp_ctrl *_this, l2tpd *_l2tpd, struct sockaddr *peer, |
| 118 | struct sockaddr *sock, void *nat_t_ctx) |
| 119 | { |
| 120 | int tunid, i; |
| 121 | bytebuffer *bytebuf; |
| 122 | time_t curr_time; |
| 123 | |
| 124 | memset(_this, 0, sizeof(l2tp_ctrl)); |
| 125 | |
| 126 | curr_time = get_monosec()((time_t)(get_nanotime() / 1000000000LL)); |
| 127 | _this->l2tpd = _l2tpd; |
| 128 | _this->state = L2TP_CTRL_STATE_IDLE0; |
| 129 | _this->last_snd_ctrl = curr_time; |
| 130 | |
| 131 | slist_init(&_this->call_list); |
| 132 | |
| 133 | /* seek a free tunnel ID */ |
| 134 | i = 0; |
Value stored to 'i' is never read | |
| 135 | _this->id = ++l2tp_ctrl_id_seq; |
| 136 | for (i = 0, tunid = _this->id; ; i++, tunid++) { |
| 137 | tunid &= 0xffff; |
| 138 | _this->tunnel_id = l2tp_ctrl_id_seq & 0xffff; |
| 139 | if (tunid == 0) |
| 140 | continue; |
| 141 | if (l2tpd_get_ctrl(_l2tpd, tunid) == NULL((void*)0)) |
| 142 | break; |
| 143 | if (i > 80000) { |
| 144 | /* this must be happen, just log it. */ |
| 145 | l2tpd_log(_l2tpd, LOG_ERR3, "Too many l2tp controls"); |
| 146 | return -1; |
| 147 | } |
| 148 | } |
| 149 | |
| 150 | _this->tunnel_id = tunid; |
| 151 | |
| 152 | L2TP_CTRL_ASSERT(peer != NULL); |
| 153 | L2TP_CTRL_ASSERT(sock != NULL); |
| 154 | memcpy(&_this->peer, peer, peer->sa_len); |
| 155 | memcpy(&_this->sock, sock, sock->sa_len); |
| 156 | |
| 157 | /* prepare send buffer */ |
| 158 | _this->winsz = L2TPD_DEFAULT_SEND_WINSZ4; |
| 159 | /* |
| 160 | * _this->winsz is informed as our receive window size. Also |
| 161 | * MIN(_this->winsz, _this->peer_winsiz) is used for the size of |
| 162 | * transmit side window. We need winsz * 2 sized buffer so that a |
| 163 | * stingy client can fill both of window separately. |
| 164 | */ |
| 165 | _this->snd_buffercnt = _this->winsz * 2; |
| 166 | if ((_this->snd_buffers = calloc(_this->snd_buffercnt, |
| 167 | sizeof(bytebuffer *))) == NULL((void*)0)) { |
| 168 | l2tpd_log(_l2tpd, LOG_ERR3, |
| 169 | "calloc() failed in %s(): %m", __func__); |
| 170 | goto fail; |
| 171 | } |
| 172 | for (i = 0; i < _this->snd_buffercnt; i++) { |
| 173 | if ((bytebuf = bytebuffer_create(L2TPD_SND_BUFSIZ2048)) == NULL((void*)0)) { |
| 174 | l2tpd_log(_l2tpd, LOG_ERR3, |
| 175 | "bytebuffer_create() failed in %s(): %m", __func__); |
| 176 | goto fail; |
| 177 | } |
| 178 | _this->snd_buffers[i] = bytebuf; |
| 179 | } |
| 180 | if ((_this->zlb_buffer = bytebuffer_create(sizeof(struct l2tp_header) |
| 181 | + 128)) == NULL((void*)0)) { |
| 182 | l2tpd_log(_l2tpd, LOG_ERR3, |
| 183 | "bytebuffer_create() failed in %s(): %m", __func__); |
| 184 | goto fail; |
| 185 | } |
| 186 | #if defined(USE_LIBSOCKUTIL) || defined(USE_SA_COOKIE1) |
| 187 | if (nat_t_ctx != NULL((void*)0)) { |
| 188 | if ((_this->sa_cookie = malloc( |
| 189 | sizeof(struct in_ipsec_sa_cookie))) != NULL((void*)0)) { |
| 190 | *(struct in_ipsec_sa_cookie *)_this->sa_cookie = |
| 191 | *(struct in_ipsec_sa_cookie *)nat_t_ctx; |
| 192 | } else { |
| 193 | l2tpd_log(_l2tpd, LOG_ERR3, |
| 194 | "creating sa_cookie failed: %m"); |
| 195 | goto fail; |
| 196 | } |
| 197 | } |
| 198 | #endif |
| 199 | _this->hello_interval = L2TP_CTRL_DEFAULT_HELLO_INTERVAL60; |
| 200 | _this->hello_timeout = L2TP_CTRL_DEFAULT_HELLO_TIMEOUT30; |
| 201 | _this->hello_io_time = curr_time; |
| 202 | |
| 203 | /* initialize timeout timer */ |
| 204 | l2tp_ctrl_reset_timeout(_this); |
| 205 | |
| 206 | /* register l2tp context */ |
| 207 | l2tpd_add_ctrl(_l2tpd, _this); |
| 208 | return 0; |
| 209 | fail: |
| 210 | l2tp_ctrl_stop(_this, 0); |
| 211 | return -1; |
| 212 | } |
| 213 | |
| 214 | /* |
| 215 | * setup {@link ::_l2tp_ctrl L2TP LNS control connection} instance |
| 216 | */ |
| 217 | static void |
| 218 | l2tp_ctrl_reload(l2tp_ctrl *_this) |
| 219 | { |
| 220 | _this->data_use_seq = L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->data_use_seq; |
| 221 | if (L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->hello_interval != 0) |
| 222 | _this->hello_interval = L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->hello_interval; |
| 223 | if (L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->hello_timeout != 0) |
| 224 | _this->hello_timeout = L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->hello_timeout; |
| 225 | } |
| 226 | |
| 227 | /* |
| 228 | * free {@link ::_l2tp_ctrl L2TP LNS control connection} instance |
| 229 | */ |
| 230 | void |
| 231 | l2tp_ctrl_destroy(l2tp_ctrl *_this) |
| 232 | { |
| 233 | L2TP_CTRL_ASSERT(_this != NULL); |
| 234 | #if defined(USE_LIBSOCKUTIL) || defined(USE_SA_COOKIE1) |
| 235 | free(_this->sa_cookie); |
| 236 | #endif |
| 237 | free(_this); |
| 238 | } |
| 239 | |
| 240 | /* |
| 241 | * nortify disconnection to peer |
| 242 | * |
| 243 | * @return 0: all CDN and StopCCN have been sent. |
| 244 | * N: if the remaining calls which still not sent CDN exist, |
| 245 | * return # of the calls. |
| 246 | * -1: when try to send of StopCCN failed. |
| 247 | */ |
| 248 | static int |
| 249 | l2tp_ctrl_send_disconnect_notify(l2tp_ctrl *_this) |
| 250 | { |
| 251 | int ncalls; |
| 252 | |
| 253 | L2TP_CTRL_ASSERT(_this != NULL) |
| 254 | L2TP_CTRL_ASSERT(_this->state == L2TP_CTRL_STATE_ESTABLISHED || |
| 255 | _this->state == L2TP_CTRL_STATE_CLEANUP_WAIT); |
| 256 | |
| 257 | /* this control is not actively closing or StopCCN have been sent */ |
| 258 | if (_this->active_closing == 0) |
| 259 | return 0; |
| 260 | |
| 261 | /* Send CDN all Calls */ |
| 262 | ncalls = 0; |
| 263 | if (slist_length(&_this->call_list) != 0) { |
| 264 | ncalls = l2tp_ctrl_disconnect_all_calls(_this, 0); |
| 265 | if (ncalls > 0) { |
| 266 | /* |
| 267 | * Call the function again to check whether the |
| 268 | * sending window is fulled. In case ncalls == 0, |
| 269 | * it means we've sent CDN for all calls. |
| 270 | */ |
| 271 | ncalls = l2tp_ctrl_disconnect_all_calls(_this, 0); |
| 272 | } |
| 273 | } |
| 274 | if (ncalls > 0) |
| 275 | return ncalls; |
| 276 | |
| 277 | if (l2tp_ctrl_send_StopCCN(_this, _this->active_closing) != 0) |
| 278 | return -1; |
| 279 | _this->active_closing = 0; |
| 280 | |
| 281 | return 0; |
| 282 | } |
| 283 | |
| 284 | /* |
| 285 | * Terminate the control connection |
| 286 | * |
| 287 | * <p> |
| 288 | * please specify an appropriate value to result( >0 ) for |
| 289 | * StopCCN ResultCode AVP, when to sent Active Close (which |
| 290 | * require StopCCN sent).</p> |
| 291 | * <p> |
| 292 | * When the return value of this function is zero, the _this |
| 293 | * is already released. The lt2p_ctrl process that was bound to it |
| 294 | * could not continue. |
| 295 | * When the return value of this function is one, the timer |
| 296 | * is reset.</p> |
| 297 | * |
| 298 | * @return return 0 if terminate process was completed. |
| 299 | */ |
| 300 | int |
| 301 | l2tp_ctrl_stop(l2tp_ctrl *_this, int result) |
| 302 | { |
| 303 | int i; |
| 304 | l2tpd *_l2tpd; |
| 305 | |
| 306 | L2TP_CTRL_ASSERT(_this != NULL); |
| 307 | |
| 308 | switch (_this->state) { |
| 309 | case L2TP_CTRL_STATE_ESTABLISHED3: |
| 310 | _this->state = L2TP_CTRL_STATE_CLEANUP_WAIT4; |
| 311 | if (result > 0) { |
| 312 | _this->active_closing = result; |
| 313 | l2tp_ctrl_send_disconnect_notify(_this); |
| 314 | break; |
| 315 | } |
| 316 | goto cleanup; |
| 317 | default: |
| 318 | l2tp_ctrl_log(_this, LOG_DEBUG7, "%s() unexpected state=%s", |
| 319 | __func__, l2tp_ctrl_state_string(_this)); |
| 320 | /* FALLTHROUGH */ |
| 321 | case L2TP_CTRL_STATE_WAIT_CTL_CONN1: |
| 322 | /* FALLTHROUGH */ |
| 323 | case L2TP_CTRL_STATE_CLEANUP_WAIT4: |
| 324 | cleanup: |
| 325 | if (slist_length(&_this->call_list) != 0) { |
| 326 | if (l2tp_ctrl_disconnect_all_calls(_this, 1) > 0) |
| 327 | break; |
| 328 | } |
| 329 | |
| 330 | l2tp_ctrl_log(_this, LOG_NOTICE5, "logtype=Finished"); |
| 331 | |
| 332 | evtimer_del(&_this->ev_timeout)event_del(&_this->ev_timeout); |
| 333 | |
| 334 | /* free send buffer */ |
| 335 | if (_this->snd_buffers != NULL((void*)0)) { |
| 336 | for (i = 0; i < _this->snd_buffercnt; i++) |
| 337 | bytebuffer_destroy(_this->snd_buffers[i]); |
| 338 | free(_this->snd_buffers); |
| 339 | _this->snd_buffers = NULL((void*)0); |
| 340 | } |
| 341 | if (_this->zlb_buffer != NULL((void*)0)) { |
| 342 | bytebuffer_destroy(_this->zlb_buffer); |
| 343 | _this->zlb_buffer = NULL((void*)0); |
| 344 | } |
| 345 | |
| 346 | /* free l2tp_call */ |
| 347 | l2tp_ctrl_destroy_all_calls(_this); |
| 348 | slist_fini(&_this->call_list); |
| 349 | |
| 350 | l2tpd_remove_ctrl(_this->l2tpd, _this->tunnel_id); |
| 351 | |
| 352 | _l2tpd = _this->l2tpd; |
| 353 | l2tp_ctrl_destroy(_this); |
| 354 | |
| 355 | l2tpd_ctrl_finished_notify(_l2tpd); |
| 356 | return 0; /* stopped */ |
| 357 | } |
| 358 | l2tp_ctrl_reset_timeout(_this); |
| 359 | |
| 360 | return 1; |
| 361 | } |
| 362 | |
| 363 | /* timeout processing */ |
| 364 | static void |
| 365 | l2tp_ctrl_timeout(int fd, short evtype, void *ctx) |
| 366 | { |
| 367 | int next_timeout, need_resend; |
| 368 | time_t curr_time; |
| 369 | l2tp_ctrl *_this; |
| 370 | l2tp_call *call; |
| 371 | |
| 372 | /* |
| 373 | * the timer must be reset, when leave this function. |
| 374 | * MEMO: l2tp_ctrl_stop() will reset the timer in it. |
| 375 | * and please remember that the l2tp_ctrl_stop() may free _this. |
| 376 | */ |
| 377 | _this = ctx; |
| 378 | L2TP_CTRL_ASSERT(_this != NULL); |
| 379 | |
| 380 | curr_time = get_monosec()((time_t)(get_nanotime() / 1000000000LL)); |
| 381 | |
| 382 | next_timeout = 2; |
| 383 | need_resend = 0; |
| 384 | |
| 385 | if (l2tp_ctrl_txwin_size(_this) > 0) { |
| 386 | if (_this->state == L2TP_CTRL_STATE_ESTABLISHED3) { |
| 387 | if (_this->hello_wait_ack != 0) { |
| 388 | /* wait Hello reply */ |
| 389 | if (curr_time - _this->hello_io_time >= |
| 390 | _this->hello_timeout) { |
| 391 | l2tp_ctrl_log(_this, LOG_NOTICE5, |
| 392 | "timeout waiting ack for hello " |
| 393 | "packets."); |
| 394 | l2tp_ctrl_stop(_this, |
| 395 | L2TP_STOP_CCN_RCODE_GENERAL1); |
| 396 | return; |
| 397 | } |
| 398 | } |
| 399 | } else if (curr_time - _this->last_snd_ctrl >= |
| 400 | L2TP_CTRL_CTRL_PKT_TIMEOUT12) { |
| 401 | l2tp_ctrl_log(_this, LOG_NOTICE5, |
| 402 | "timeout waiting ack for ctrl packets."); |
| 403 | l2tp_ctrl_stop(_this, |
| 404 | L2TP_STOP_CCN_RCODE_GENERAL1); |
| 405 | return; |
| 406 | } |
| 407 | need_resend = 1; |
| 408 | } else { |
| 409 | for (slist_itr_first(&_this->call_list); |
| 410 | slist_itr_has_next(&_this->call_list);) { |
| 411 | call = slist_itr_next(&_this->call_list); |
| 412 | if (call->state == L2TP_CALL_STATE_CLEANUP_WAIT3) { |
| 413 | l2tp_call_destroy(call, 1); |
| 414 | slist_itr_remove(&_this->call_list); |
| 415 | } |
| 416 | } |
| 417 | } |
| 418 | |
| 419 | switch (_this->state) { |
| 420 | case L2TP_CTRL_STATE_IDLE0: |
| 421 | /* |
| 422 | * idle: |
| 423 | * XXX: never happen in current implementation |
| 424 | */ |
| 425 | l2tp_ctrl_log(_this, LOG_ERR3, |
| 426 | "Internal error, timeout on illegal state=idle"); |
| 427 | l2tp_ctrl_stop(_this, L2TP_STOP_CCN_RCODE_GENERAL1); |
| 428 | break; |
| 429 | case L2TP_CTRL_STATE_WAIT_CTL_CONN1: |
| 430 | /* |
| 431 | * wait-ctrl-conn: |
| 432 | * if there is no ack for SCCRP, the peer will |
| 433 | * resend SCCRQ. however this implementation can |
| 434 | * not recognize that the SCCRQ was resent or not. |
| 435 | * Therefore, never resent from this side. |
| 436 | */ |
| 437 | need_resend = 0; |
| 438 | break; |
| 439 | case L2TP_CTRL_STATE_ESTABLISHED3: |
| 440 | if (slist_length(&_this->call_list) == 0 && |
| 441 | curr_time - _this->last_snd_ctrl >= |
| 442 | L2TP_CTRL_WAIT_CALL_TIMEOUT16) { |
| 443 | if (_this->ncalls == 0) |
| 444 | /* fail to receive first call */ |
| 445 | l2tp_ctrl_log(_this, LOG_WARNING4, |
| 446 | "timeout waiting call"); |
| 447 | l2tp_ctrl_stop(_this, |
| 448 | L2TP_STOP_CCN_RCODE_GENERAL1); |
| 449 | return; |
| 450 | } |
| 451 | if (_this->hello_wait_ack == 0 && _this->hello_interval > 0) { |
| 452 | /* send Hello */ |
| 453 | if (curr_time - _this->hello_interval >= |
| 454 | _this->hello_io_time) { |
| 455 | if (l2tp_ctrl_send_HELLO(_this) == 0) |
| 456 | /* success */ |
| 457 | _this->hello_wait_ack = 1; |
| 458 | _this->hello_io_time = curr_time; |
| 459 | need_resend = 0; |
| 460 | } |
| 461 | } |
| 462 | break; |
| 463 | case L2TP_CTRL_STATE_CLEANUP_WAIT4: |
| 464 | if (curr_time - _this->last_snd_ctrl >= |
| 465 | L2TP_CTRL_CLEANUP_WAIT_TIME3) { |
| 466 | l2tp_ctrl_log(_this, LOG_NOTICE5, |
| 467 | "Cleanup timeout state=%d", _this->state); |
| 468 | l2tp_ctrl_stop(_this, 0); |
| 469 | return; |
| 470 | } |
| 471 | if (_this->active_closing != 0) |
| 472 | l2tp_ctrl_send_disconnect_notify(_this); |
| 473 | break; |
| 474 | default: |
| 475 | l2tp_ctrl_log(_this, LOG_ERR3, |
| 476 | "Internal error, timeout on illegal state=%d", |
| 477 | _this->state); |
| 478 | l2tp_ctrl_stop(_this, L2TP_STOP_CCN_RCODE_GENERAL1); |
| 479 | return; |
| 480 | } |
| 481 | /* resend if required */ |
| 482 | if (need_resend) |
| 483 | l2tp_ctrl_resend_una_packets(_this, true1); |
| 484 | l2tp_ctrl_reset_timeout(_this); |
| 485 | } |
| 486 | |
| 487 | int |
| 488 | l2tp_ctrl_send(l2tp_ctrl *_this, const void *msg, int len) |
| 489 | { |
| 490 | int rval; |
| 491 | |
| 492 | #ifdef USE_LIBSOCKUTIL |
| 493 | if (_this->sa_cookie != NULL((void*)0)) |
| 494 | rval = sendfromto_nat_t(LISTENER_SOCK(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->sock, msg, len, 0, |
| 495 | (struct sockaddr *)&_this->sock, |
| 496 | (struct sockaddr *)&_this->peer, _this->sa_cookie); |
| 497 | else |
| 498 | rval = sendfromto(LISTENER_SOCK(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->sock, msg, len, 0, |
| 499 | (struct sockaddr *)&_this->sock, |
| 500 | (struct sockaddr *)&_this->peer); |
| 501 | #else |
| 502 | #ifdef USE_SA_COOKIE1 |
| 503 | if (_this->sa_cookie != NULL((void*)0)) |
| 504 | rval = sendto_nat_t(LISTENER_SOCK(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->sock, msg, len, 0, |
| 505 | (struct sockaddr *)&_this->peer, _this->peer.ss_len, |
| 506 | _this->sa_cookie); |
| 507 | else |
| 508 | #endif |
| 509 | rval = sendto(LISTENER_SOCK(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->sock, msg, len, 0, |
| 510 | (struct sockaddr *)&_this->peer, _this->peer.ss_len); |
| 511 | #endif |
| 512 | return rval; |
| 513 | } |
| 514 | |
| 515 | /* resend una packets */ |
| 516 | static int |
| 517 | l2tp_ctrl_resend_una_packets(l2tp_ctrl *_this, bool_Bool resend) |
| 518 | { |
| 519 | uint16_t seq; |
| 520 | bytebuffer *bytebuf; |
| 521 | struct l2tp_header *header; |
| 522 | int nsend; |
| 523 | |
| 524 | nsend = 0; |
| 525 | for (seq = _this->snd_una; SEQ_LT(seq, _this->snd_nxt)((int16_t)((seq) - (_this->snd_nxt)) < 0); seq++) { |
| 526 | if (!l2tp_ctrl_in_peer_window(_this, seq)) |
| 527 | break; |
| 528 | if (SEQ_LT(seq, _this->snd_last)((int16_t)((seq) - (_this->snd_last)) < 0) && !resend) |
| 529 | continue; |
| 530 | bytebuf = _this->snd_buffers[seq % _this->snd_buffercnt]; |
| 531 | header = bytebuffer_pointer(bytebuf); |
| 532 | header->nr = htons(_this->rcv_nxt)(__uint16_t)(__builtin_constant_p(_this->rcv_nxt) ? (__uint16_t )(((__uint16_t)(_this->rcv_nxt) & 0xffU) << 8 | ( (__uint16_t)(_this->rcv_nxt) & 0xff00U) >> 8) : __swap16md (_this->rcv_nxt)); |
| 533 | _this->snd_lastnr = _this->rcv_nxt; |
| 534 | #ifdef L2TP_CTRL_DEBUG |
| 535 | if (debuglevel >= 3) { |
| 536 | l2tp_ctrl_log(_this, DEBUG_LEVEL_3( 3 << 24), "RESEND seq=%u", |
| 537 | ntohs(header->ns)(__uint16_t)(__builtin_constant_p(header->ns) ? (__uint16_t )(((__uint16_t)(header->ns) & 0xffU) << 8 | ((__uint16_t )(header->ns) & 0xff00U) >> 8) : __swap16md(header ->ns))); |
| 538 | show_hd(debug_get_debugfp(), |
| 539 | bytebuffer_pointer(bytebuf), |
| 540 | bytebuffer_remaining(bytebuf)); |
| 541 | } |
| 542 | #endif |
| 543 | if (l2tp_ctrl_send(_this, bytebuffer_pointer(bytebuf), |
| 544 | bytebuffer_remaining(bytebuf)) < 0) { |
| 545 | l2tp_ctrl_log(_this, LOG_ERR3, |
| 546 | "sendto() failed in %s: %m", __func__); |
| 547 | return -1; |
| 548 | } |
| 549 | nsend++; |
| 550 | } |
| 551 | return nsend; |
| 552 | } |
| 553 | |
| 554 | /* free all calls */ |
| 555 | static void |
| 556 | l2tp_ctrl_destroy_all_calls(l2tp_ctrl *_this) |
| 557 | { |
| 558 | l2tp_call *call; |
| 559 | |
| 560 | L2TP_CTRL_ASSERT(_this != NULL); |
| 561 | |
| 562 | while ((call = slist_remove_first(&_this->call_list)) != NULL((void*)0)) |
| 563 | l2tp_call_destroy(call, 1); |
| 564 | } |
| 565 | |
| 566 | |
| 567 | /* disconnect all calls on the control context |
| 568 | * @return return # of calls that is not waiting cleanup. |
| 569 | */ |
| 570 | static int |
| 571 | l2tp_ctrl_disconnect_all_calls(l2tp_ctrl *_this, int drop) |
| 572 | { |
| 573 | int i, len, ncalls; |
| 574 | l2tp_call *call; |
| 575 | |
| 576 | L2TP_CTRL_ASSERT(_this != NULL); |
| 577 | |
| 578 | ncalls = 0; |
| 579 | len = slist_length(&_this->call_list); |
| 580 | for (i = 0; i < len; i++) { |
| 581 | call = slist_get(&_this->call_list, i); |
| 582 | if (call->state != L2TP_CALL_STATE_CLEANUP_WAIT3) { |
| 583 | ncalls++; |
| 584 | if (l2tp_ctrl_txwin_is_full(_this)) { |
| 585 | L2TP_CTRL_DBG((_this, LOG_INFO, |
| 586 | "Too many calls. Sending window is not " |
| 587 | "enough to send CDN to all clients.")); |
| 588 | if (drop) |
| 589 | l2tp_call_drop(call); |
| 590 | } else |
| 591 | l2tp_call_admin_disconnect(call); |
| 592 | } |
| 593 | } |
| 594 | return ncalls; |
| 595 | } |
| 596 | |
| 597 | /* reset timeout */ |
| 598 | static void |
| 599 | l2tp_ctrl_reset_timeout(l2tp_ctrl *_this) |
| 600 | { |
| 601 | int intvl; |
| 602 | struct timeval tv0; |
| 603 | |
| 604 | L2TP_CTRL_ASSERT(_this != NULL); |
| 605 | |
| 606 | if (evtimer_initialized(&_this->ev_timeout)((&_this->ev_timeout)->ev_flags & 0x80)) |
| 607 | evtimer_del(&_this->ev_timeout)event_del(&_this->ev_timeout); |
| 608 | |
| 609 | switch (_this->state) { |
| 610 | case L2TP_CTRL_STATE_CLEANUP_WAIT4: |
| 611 | intvl = 1; |
| 612 | break; |
| 613 | default: |
| 614 | intvl = 2; |
| 615 | break; |
| 616 | } |
| 617 | tv0.tv_usec = 0; |
| 618 | tv0.tv_sec = intvl; |
| 619 | if (!evtimer_initialized(&_this->ev_timeout)((&_this->ev_timeout)->ev_flags & 0x80)) |
| 620 | evtimer_set(&_this->ev_timeout, l2tp_ctrl_timeout, _this)event_set(&_this->ev_timeout, -1, 0, l2tp_ctrl_timeout , _this); |
| 621 | evtimer_add(&_this->ev_timeout, &tv0)event_add(&_this->ev_timeout, &tv0); |
| 622 | } |
| 623 | |
| 624 | /* |
| 625 | * protocols / send and receive |
| 626 | */ |
| 627 | /* Receive packet */ |
| 628 | void |
| 629 | l2tp_ctrl_input(l2tpd *_this, int listener_index, struct sockaddr *peer, |
| 630 | struct sockaddr *sock, void *nat_t_ctx, u_char *pkt, int pktlen) |
| 631 | { |
| 632 | int i, len, offsiz, reqlen, is_ctrl; |
| 633 | uint16_t mestype; |
| 634 | struct l2tp_avp *avp, *avp0; |
| 635 | l2tp_ctrl *ctrl; |
| 636 | l2tp_call *call; |
| 637 | char buf[L2TP_AVP_MAXSIZ1024], errmsg[256]; |
| 638 | time_t curr_time; |
| 639 | u_char *pkt0; |
| 640 | struct l2tp_header hdr; |
| 641 | char hbuf[NI_MAXHOST256 + NI_MAXSERV32 + 16]; |
| 642 | |
| 643 | ctrl = NULL((void*)0); |
| 644 | curr_time = get_monosec()((time_t)(get_nanotime() / 1000000000LL)); |
| 645 | pkt0 = pkt; |
| 646 | |
| 647 | L2TP_CTRL_ASSERT(peer->sa_family == sock->sa_family); |
| 648 | L2TP_CTRL_ASSERT(peer->sa_family == AF_INET || |
| 649 | peer->sa_family == AF_INET6) |
| 650 | /* |
| 651 | * Parse L2TP Header |
| 652 | */ |
| 653 | memset(&hdr, 0, sizeof(hdr)); |
| 654 | if (pktlen < 2) { |
| 655 | snprintf(errmsg, sizeof(errmsg), "a short packet. " |
| 656 | "length=%d", pktlen); |
| 657 | goto bad_packet; |
| 658 | } |
| 659 | memcpy(&hdr, pkt, 2); |
| 660 | pkt += 2; |
| 661 | if (hdr.ver != L2TP_HEADER_VERSION_RFC26610x02) { |
| 662 | /* XXX: only RFC2661 is supported */ |
| 663 | snprintf(errmsg, sizeof(errmsg), |
| 664 | "Unsupported version at header = %d", hdr.ver); |
| 665 | goto bad_packet; |
| 666 | } |
| 667 | is_ctrl = (hdr.t != 0)? 1 : 0; |
| 668 | |
| 669 | /* calc required length */ |
| 670 | reqlen = 6; /* for Flags, Tunnel-Id, Session-Id field */ |
| 671 | if (hdr.l) reqlen += 2; /* for Length field (opt) */ |
| 672 | if (hdr.s) reqlen += 4; /* for Ns, Nr field (opt) */ |
| 673 | if (hdr.o) reqlen += 2; /* for Offset Size field (opt) */ |
| 674 | if (reqlen > pktlen) { |
| 675 | snprintf(errmsg, sizeof(errmsg), |
| 676 | "a short packet. length=%d", pktlen); |
| 677 | goto bad_packet; |
| 678 | } |
| 679 | |
| 680 | if (hdr.l != 0) { |
| 681 | GETSHORT(hdr.length, pkt){ hdr.length = *(pkt)++ << 8; hdr.length |= *(pkt)++; }; |
| 682 | if (hdr.length > pktlen) { |
| 683 | snprintf(errmsg, sizeof(errmsg), |
| 684 | "Actual packet size is smaller than the length " |
| 685 | "field %d < %d", pktlen, hdr.length); |
| 686 | goto bad_packet; |
| 687 | } |
| 688 | pktlen = hdr.length; /* remove trailing trash */ |
| 689 | } |
| 690 | GETSHORT(hdr.tunnel_id, pkt){ hdr.tunnel_id = *(pkt)++ << 8; hdr.tunnel_id |= *(pkt )++; }; |
| 691 | GETSHORT(hdr.session_id, pkt){ hdr.session_id = *(pkt)++ << 8; hdr.session_id |= *(pkt )++; }; |
| 692 | if (hdr.s != 0) { |
| 693 | GETSHORT(hdr.ns, pkt){ hdr.ns = *(pkt)++ << 8; hdr.ns |= *(pkt)++; }; |
| 694 | GETSHORT(hdr.nr, pkt){ hdr.nr = *(pkt)++ << 8; hdr.nr |= *(pkt)++; }; |
| 695 | } |
| 696 | if (hdr.o != 0) { |
| 697 | GETSHORT(offsiz, pkt){ offsiz = *(pkt)++ << 8; offsiz |= *(pkt)++; }; |
| 698 | if (pktlen < offsiz) { |
| 699 | snprintf(errmsg, sizeof(errmsg), |
| 700 | "offset field is bigger than remaining packet " |
| 701 | "length %d > %d", offsiz, pktlen); |
| 702 | goto bad_packet; |
| 703 | } |
| 704 | pkt += offsiz; |
| 705 | } |
| 706 | L2TP_CTRL_ASSERT(pkt - pkt0 == reqlen); |
| 707 | pktlen -= (pkt - pkt0); /* cut down the length of header */ |
| 708 | |
| 709 | ctrl = NULL((void*)0); |
| 710 | memset(buf, 0, sizeof(buf)); |
| 711 | mestype = 0; |
| 712 | avp = NULL((void*)0); |
| 713 | |
| 714 | if (is_ctrl) { |
| 715 | avp0 = (struct l2tp_avp *)buf; |
| 716 | avp = avp_find_message_type_avp(avp0, pkt, pktlen); |
| 717 | if (avp != NULL((void*)0)) |
| 718 | mestype = avp->attr_value[0] << 8 | avp->attr_value[1]; |
| 719 | } |
| 720 | ctrl = l2tpd_get_ctrl(_this, hdr.tunnel_id); |
| 721 | |
| 722 | if (ctrl == NULL((void*)0)) { |
| 723 | /* new control */ |
| 724 | if (!is_ctrl) { |
| 725 | snprintf(errmsg, sizeof(errmsg), |
| 726 | "bad data message: tunnelId=%d is not " |
| 727 | "found.", hdr.tunnel_id); |
| 728 | goto bad_packet; |
| 729 | } |
| 730 | if (mestype != L2TP_AVP_MESSAGE_TYPE_SCCRQ1) { |
| 731 | snprintf(errmsg, sizeof(errmsg), |
| 732 | "bad control message: tunnelId=%d is not " |
| 733 | "found. mestype=%s", hdr.tunnel_id, |
| 734 | avp_mes_type_string(mestype)); |
| 735 | goto bad_packet; |
| 736 | } |
| 737 | |
| 738 | if ((ctrl = l2tp_ctrl_create()) == NULL((void*)0)) { |
| 739 | l2tp_ctrl_log(ctrl, LOG_ERR3, |
| 740 | "l2tp_ctrl_create() failed: %m"); |
| 741 | goto fail; |
| 742 | } |
| 743 | |
| 744 | if (l2tp_ctrl_init(ctrl, _this, peer, sock, nat_t_ctx) != 0) { |
| 745 | l2tp_ctrl_log(ctrl, LOG_ERR3, |
| 746 | "l2tp_ctrl_start() failed: %m"); |
| 747 | goto fail; |
| 748 | } |
| 749 | |
| 750 | ctrl->listener_index = listener_index; |
| 751 | l2tp_ctrl_reload(ctrl); |
| 752 | } else { |
| 753 | /* |
| 754 | * treat as an error if src address and port is not |
| 755 | * match. (because it is potentially DoS attach) |
| 756 | */ |
| 757 | int notmatch = 0; |
| 758 | |
| 759 | if (ctrl->peer.ss_family != peer->sa_family) |
| 760 | notmatch = 1; |
| 761 | else if (peer->sa_family == AF_INET2) { |
| 762 | if (SIN(peer)((struct sockaddr_in *)(peer))->sin_addr.s_addr != |
| 763 | SIN(&ctrl->peer)((struct sockaddr_in *)(&ctrl->peer))->sin_addr.s_addr || |
| 764 | SIN(peer)((struct sockaddr_in *)(peer))->sin_port != SIN(&ctrl->peer)((struct sockaddr_in *)(&ctrl->peer))->sin_port) |
| 765 | notmatch = 1; |
| 766 | } else if (peer->sa_family == AF_INET624) { |
| 767 | if (!IN6_ARE_ADDR_EQUAL(&(SIN6(peer)->sin6_addr),(memcmp(&(&(((struct sockaddr_in6 *)(peer))->sin6_addr ))->__u6_addr.__u6_addr8[0], &(&(((struct sockaddr_in6 *)(&ctrl->peer))->sin6_addr))->__u6_addr.__u6_addr8 [0], sizeof(struct in6_addr)) == 0) |
| 768 | &(SIN6(&ctrl->peer)->sin6_addr))(memcmp(&(&(((struct sockaddr_in6 *)(peer))->sin6_addr ))->__u6_addr.__u6_addr8[0], &(&(((struct sockaddr_in6 *)(&ctrl->peer))->sin6_addr))->__u6_addr.__u6_addr8 [0], sizeof(struct in6_addr)) == 0) || |
| 769 | SIN6(peer)((struct sockaddr_in6 *)(peer))->sin6_port != |
| 770 | SIN6(&ctrl->peer)((struct sockaddr_in6 *)(&ctrl->peer))->sin6_port) |
| 771 | notmatch = 1; |
| 772 | } |
| 773 | if (notmatch) { |
| 774 | snprintf(errmsg, sizeof(errmsg), |
| 775 | "tunnelId=%u is already assigned for %s", |
| 776 | hdr.tunnel_id, addrport_tostring( |
| 777 | (struct sockaddr *)&ctrl->peer, |
| 778 | ctrl->peer.ss_len, hbuf, sizeof(hbuf))); |
| 779 | goto bad_packet; |
| 780 | } |
| 781 | } |
| 782 | ctrl->last_rcv = curr_time; |
| 783 | call = NULL((void*)0); |
| 784 | if (hdr.session_id != 0) { |
| 785 | /* search l2tp_call by Session ID */ |
| 786 | /* linear search is enough for this purpose */ |
| 787 | len = slist_length(&ctrl->call_list); |
| 788 | for (i = 0; i < len; i++) { |
| 789 | call = slist_get(&ctrl->call_list, i); |
| 790 | if (call->session_id == hdr.session_id) |
| 791 | break; |
| 792 | call = NULL((void*)0); |
| 793 | } |
| 794 | } |
| 795 | if (!is_ctrl) { |
| 796 | int delayed = 0; |
| 797 | |
| 798 | /* L2TP data */ |
| 799 | if (ctrl->state != L2TP_CTRL_STATE_ESTABLISHED3) { |
| 800 | l2tp_ctrl_log(ctrl, LOG_WARNING4, |
| 801 | "Received Data packet in '%s'", |
| 802 | l2tp_ctrl_state_string(ctrl)); |
| 803 | goto fail; |
| 804 | } |
| 805 | if (call == NULL((void*)0)) { |
| 806 | l2tp_ctrl_log(ctrl, LOG_WARNING4, |
| 807 | "Received a data packet but it has no call. " |
| 808 | "session_id=%u", hdr.session_id); |
| 809 | goto fail; |
| 810 | } |
| 811 | L2TP_CTRL_DBG((ctrl, DEBUG_LEVEL_2, |
| 812 | "call=%u RECV ns=%u nr=%u snd_nxt=%u rcv_nxt=%u len=%d", |
| 813 | call->id, hdr.ns, hdr.nr, call->snd_nxt, call->rcv_nxt, |
| 814 | pktlen)); |
| 815 | if (call->state != L2TP_CALL_STATE_ESTABLISHED2){ |
| 816 | l2tp_ctrl_log(ctrl, LOG_WARNING4, |
| 817 | "Received a data packet but call is not " |
| 818 | "established"); |
| 819 | goto fail; |
| 820 | } |
| 821 | |
| 822 | if (hdr.s != 0) { |
| 823 | if (SEQ_LT(hdr.ns, call->rcv_nxt)((int16_t)((hdr.ns) - (call->rcv_nxt)) < 0)) { |
| 824 | if (SEQ_LT(hdr.ns,((int16_t)((hdr.ns) - (call->rcv_nxt - 64)) < 0) |
| 825 | call->rcv_nxt - L2TP_CALL_DELAY_LIMIT)((int16_t)((hdr.ns) - (call->rcv_nxt - 64)) < 0)) { |
| 826 | /* sequence number seems to be delayed */ |
| 827 | /* XXX: need to log? */ |
| 828 | L2TP_CTRL_DBG((ctrl, LOG_DEBUG, |
| 829 | "receive a out of sequence " |
| 830 | "data packet: %u < %u.", |
| 831 | hdr.ns, call->rcv_nxt)); |
| 832 | return; |
| 833 | } |
| 834 | delayed = 1; |
| 835 | } else { |
| 836 | call->rcv_nxt = hdr.ns + 1; |
| 837 | } |
| 838 | } |
| 839 | |
| 840 | l2tp_call_ppp_input(call, pkt, pktlen, delayed); |
| 841 | |
| 842 | return; |
| 843 | } |
| 844 | if (hdr.s != 0) { |
| 845 | L2TP_CTRL_DBG((ctrl, DEBUG_LEVEL_2, |
| 846 | "RECV %s ns=%u nr=%u snd_nxt=%u snd_una=%u rcv_nxt=%u " |
| 847 | "len=%d", (is_ctrl)? "C" : "", hdr.ns, hdr.nr, |
| 848 | ctrl->snd_nxt, ctrl->snd_una, ctrl->rcv_nxt, pktlen)); |
| 849 | |
| 850 | if (pktlen <= 0) |
| 851 | l2tp_ctrl_log(ctrl, LOG_INFO6, "RecvZLB"); |
| 852 | |
| 853 | if (SEQ_GT(hdr.nr, ctrl->snd_una)((int16_t)((hdr.nr) - (ctrl->snd_una)) > 0)) { |
| 854 | /* a new ack arrived */ |
| 855 | if (SEQ_GT(hdr.nr, ctrl->snd_nxt)((int16_t)((hdr.nr) - (ctrl->snd_nxt)) > 0)) { |
| 856 | /* ack is proceeded us */ |
| 857 | l2tp_ctrl_log(ctrl, LOG_INFO6, |
| 858 | "Received message has bad Nr field: " |
| 859 | "%u < %u", ctrl->snd_nxt, hdr.nr); |
| 860 | goto fail; |
| 861 | } |
| 862 | ctrl->snd_una = hdr.nr; |
| 863 | /* peer window is moved. send out pending packets */ |
| 864 | l2tp_ctrl_resend_una_packets(ctrl, false0); |
| 865 | } |
| 866 | if (l2tp_ctrl_txwin_size(ctrl) <= 0) { |
| 867 | /* no waiting ack */ |
| 868 | if (ctrl->hello_wait_ack != 0) { |
| 869 | /* |
| 870 | * Reset Hello state, as an ack for the Hello |
| 871 | * is received. |
| 872 | */ |
| 873 | ctrl->hello_wait_ack = 0; |
| 874 | ctrl->hello_io_time = curr_time; |
| 875 | } |
| 876 | switch (ctrl->state) { |
| 877 | case L2TP_CTRL_STATE_CLEANUP_WAIT4: |
| 878 | l2tp_ctrl_stop(ctrl, 0); |
| 879 | return; |
| 880 | } |
| 881 | } |
| 882 | if (hdr.ns != ctrl->rcv_nxt) { |
| 883 | /* there are remaining packet */ |
| 884 | if (l2tp_ctrl_resend_una_packets(ctrl, true1) <= 0) { |
| 885 | /* resend or sent ZLB */ |
| 886 | l2tp_ctrl_send_ZLB(ctrl); |
| 887 | } |
| 888 | #ifdef L2TP_CTRL_DEBUG |
| 889 | if (pktlen != 0) { /* not ZLB */ |
| 890 | L2TP_CTRL_DBG((ctrl, LOG_DEBUG, |
| 891 | "receive out of sequence %u must be %u. " |
| 892 | "mestype=%s", hdr.ns, ctrl->rcv_nxt, |
| 893 | avp_mes_type_string(mestype))); |
| 894 | } |
| 895 | #endif |
| 896 | return; |
| 897 | } |
| 898 | if (pktlen <= 0) |
| 899 | return; /* ZLB */ |
| 900 | |
| 901 | if (!l2tp_ctrl_in_our_window(ctrl, hdr.ns)) { |
| 902 | l2tp_ctrl_log(ctrl, LOG_WARNING4, |
| 903 | "received message is outside of window. " |
| 904 | "ns=%d window=%u:%u", |
| 905 | hdr.ns, ctrl->snd_lastnr, |
| 906 | (uint16_t)(ctrl->snd_lastnr + ctrl->winsz - 1)); |
| 907 | return; |
| 908 | } |
| 909 | |
| 910 | ctrl->rcv_nxt++; |
| 911 | if (avp == NULL((void*)0)) { |
| 912 | l2tpd_log(_this, LOG_WARNING4, |
| 913 | "bad control message: no message-type AVP."); |
| 914 | goto fail; |
| 915 | } |
| 916 | } |
| 917 | |
| 918 | /* |
| 919 | * state machine (RFC2661 pp. 56-57) |
| 920 | */ |
| 921 | switch (ctrl->state) { |
| 922 | case L2TP_CTRL_STATE_IDLE0: |
| 923 | switch (mestype) { |
| 924 | case L2TP_AVP_MESSAGE_TYPE_SCCRQ1: |
| 925 | if (l2tp_ctrl_recv_SCCRQ(ctrl, pkt, pktlen, _this, |
| 926 | peer) == 0) { |
| 927 | /* acceptable */ |
| 928 | l2tp_ctrl_send_SCCRP(ctrl); |
| 929 | ctrl->state = L2TP_CTRL_STATE_WAIT_CTL_CONN1; |
| 930 | return; |
| 931 | } |
| 932 | /* |
| 933 | * in case un-acceptable, it was already processed |
| 934 | * at l2tcp_ctrl_recv_SCCRQ |
| 935 | */ |
| 936 | return; |
| 937 | case L2TP_AVP_MESSAGE_TYPE_SCCRP2: |
| 938 | /* |
| 939 | * RFC specifies that sent of StopCCN in the state, |
| 940 | * However as this implementation only support Passive |
| 941 | * open, this packet will not received. |
| 942 | */ |
| 943 | /* FALLTHROUGH */ |
| 944 | case L2TP_AVP_MESSAGE_TYPE_SCCCN3: |
| 945 | default: |
| 946 | break; |
| 947 | } |
| 948 | goto fsm_fail; |
| 949 | |
| 950 | case L2TP_CTRL_STATE_WAIT_CTL_CONN1: |
| 951 | /* Wait-Ctl-Conn */ |
| 952 | switch (mestype) { |
| 953 | case L2TP_AVP_MESSAGE_TYPE_SCCCN3: |
| 954 | l2tp_ctrl_log(ctrl, LOG_INFO6, "RecvSCCN"); |
| 955 | if (l2tp_ctrl_send_ZLB(ctrl) == 0) { |
| 956 | ctrl->state = L2TP_CTRL_STATE_ESTABLISHED3; |
| 957 | } |
| 958 | return; |
| 959 | case L2TP_AVP_MESSAGE_TYPE_StopCCN4: |
| 960 | goto receive_stop_ccn; |
| 961 | case L2TP_AVP_MESSAGE_TYPE_SCCRQ1: |
| 962 | case L2TP_AVP_MESSAGE_TYPE_SCCRP2: |
| 963 | default: |
| 964 | break; |
| 965 | } |
| 966 | break; /* fsm_fail */ |
| 967 | case L2TP_CTRL_STATE_ESTABLISHED3: |
| 968 | /* Established */ |
| 969 | switch (mestype) { |
| 970 | case L2TP_AVP_MESSAGE_TYPE_SCCCN3: |
| 971 | case L2TP_AVP_MESSAGE_TYPE_SCCRQ1: |
| 972 | case L2TP_AVP_MESSAGE_TYPE_SCCRP2: |
| 973 | break; |
| 974 | receive_stop_ccn: |
| 975 | case L2TP_AVP_MESSAGE_TYPE_StopCCN4: |
| 976 | l2tp_ctrl_recv_StopCCN(ctrl, pkt, pktlen); |
| 977 | l2tp_ctrl_send_ZLB(ctrl); |
| 978 | l2tp_ctrl_stop(ctrl, 0); |
| 979 | return; |
| 980 | |
| 981 | case L2TP_AVP_MESSAGE_TYPE_HELLO6: |
| 982 | l2tp_ctrl_send_ZLB(ctrl); |
| 983 | return; |
| 984 | case L2TP_AVP_MESSAGE_TYPE_CDN14: |
| 985 | case L2TP_AVP_MESSAGE_TYPE_ICRP11: |
| 986 | case L2TP_AVP_MESSAGE_TYPE_ICCN12: |
| 987 | if (call == NULL((void*)0)) { |
| 988 | l2tp_ctrl_log(ctrl, LOG_INFO6, |
| 989 | "Unknown call message: %s", |
| 990 | avp_mes_type_string(mestype)); |
| 991 | goto fail; |
| 992 | } |
| 993 | /* FALLTHROUGH */ |
| 994 | case L2TP_AVP_MESSAGE_TYPE_ICRQ10: |
| 995 | l2tp_call_recv_packet(ctrl, call, mestype, pkt, |
| 996 | pktlen); |
| 997 | return; |
| 998 | default: |
| 999 | break; |
| 1000 | } |
| 1001 | break; /* fsm_fail */ |
| 1002 | case L2TP_CTRL_STATE_CLEANUP_WAIT4: |
| 1003 | if (mestype == L2TP_AVP_MESSAGE_TYPE_StopCCN4) { |
| 1004 | /* |
| 1005 | * We left ESTABLISHED state, but the peer sent StopCCN. |
| 1006 | */ |
| 1007 | goto receive_stop_ccn; |
| 1008 | } |
| 1009 | break; /* fsm_fail */ |
| 1010 | } |
| 1011 | |
| 1012 | fsm_fail: |
| 1013 | /* state machine error */ |
| 1014 | l2tp_ctrl_log(ctrl, LOG_WARNING4, "Received %s in '%s' state", |
| 1015 | avp_mes_type_string(mestype), l2tp_ctrl_state_string(ctrl)); |
| 1016 | l2tp_ctrl_stop(ctrl, L2TP_STOP_CCN_RCODE_FSM_ERROR7); |
| 1017 | |
| 1018 | return; |
| 1019 | fail: |
| 1020 | if (ctrl != NULL((void*)0) && mestype != 0) { |
| 1021 | l2tp_ctrl_log(ctrl, LOG_WARNING4, "Received %s in '%s' state", |
| 1022 | avp_mes_type_string(mestype), l2tp_ctrl_state_string(ctrl)); |
| 1023 | l2tp_ctrl_stop(ctrl, L2TP_STOP_CCN_RCODE_GENERAL_ERROR2); |
| 1024 | } |
| 1025 | return; |
| 1026 | |
| 1027 | bad_packet: |
| 1028 | l2tpd_log(_this, LOG_INFO6, "Received from=%s: %s", |
| 1029 | addrport_tostring(peer, peer->sa_len, hbuf, sizeof(hbuf)), errmsg); |
| 1030 | |
| 1031 | return; |
| 1032 | } |
| 1033 | |
| 1034 | static int |
| 1035 | l2tp_ctrl_txwin_size(l2tp_ctrl *_this) |
| 1036 | { |
| 1037 | uint16_t sz; |
| 1038 | |
| 1039 | sz = _this->snd_nxt - _this->snd_una; |
| 1040 | |
| 1041 | L2TP_CTRL_ASSERT(sz <= _this->buffercnt); |
| 1042 | |
| 1043 | return sz; |
| 1044 | } |
| 1045 | |
| 1046 | static bool_Bool |
| 1047 | l2tp_ctrl_txwin_is_full(l2tp_ctrl *_this) |
| 1048 | { |
| 1049 | return (l2tp_ctrl_txwin_size(_this) >= _this->snd_buffercnt)? 1 : 0; |
| 1050 | } |
| 1051 | |
| 1052 | static bool_Bool |
| 1053 | l2tp_ctrl_in_peer_window(l2tp_ctrl *_this, uint16_t seq) |
| 1054 | { |
| 1055 | uint16_t off; |
| 1056 | int winsz; |
| 1057 | |
| 1058 | winsz = MINIMUM(_this->winsz, _this->peer_winsz)(((_this->winsz) < (_this->peer_winsz)) ? (_this-> winsz) : (_this->peer_winsz)); |
| 1059 | off = seq - _this->snd_una; |
| 1060 | |
| 1061 | return ((off < winsz)? true1 : false0); |
| 1062 | } |
| 1063 | |
| 1064 | static bool_Bool |
| 1065 | l2tp_ctrl_in_our_window(l2tp_ctrl *_this, uint16_t seq) |
| 1066 | { |
| 1067 | uint16_t off; |
| 1068 | |
| 1069 | off = seq - _this->snd_lastnr; |
| 1070 | |
| 1071 | return ((off < _this->winsz)? true1 : false0); |
| 1072 | } |
| 1073 | /* send control packet */ |
| 1074 | int |
| 1075 | l2tp_ctrl_send_packet(l2tp_ctrl *_this, int call_id, bytebuffer *bytebuf) |
| 1076 | { |
| 1077 | struct l2tp_header *hdr; |
| 1078 | int rval; |
| 1079 | time_t curr_time; |
| 1080 | uint16_t seq; |
| 1081 | |
| 1082 | curr_time = get_monosec()((time_t)(get_nanotime() / 1000000000LL)); |
| 1083 | |
| 1084 | bytebuffer_flip(bytebuf); |
| 1085 | hdr = (struct l2tp_header *)bytebuffer_pointer(bytebuf); |
| 1086 | memset(hdr, 0, sizeof(*hdr)); |
| 1087 | |
| 1088 | hdr->t = 1; |
| 1089 | hdr->ver = L2TP_HEADER_VERSION_RFC26610x02; |
| 1090 | hdr->l = 1; |
| 1091 | hdr->length = htons(bytebuffer_remaining(bytebuf))(__uint16_t)(__builtin_constant_p(bytebuffer_remaining(bytebuf )) ? (__uint16_t)(((__uint16_t)(bytebuffer_remaining(bytebuf) ) & 0xffU) << 8 | ((__uint16_t)(bytebuffer_remaining (bytebuf)) & 0xff00U) >> 8) : __swap16md(bytebuffer_remaining (bytebuf))); |
| 1092 | hdr->tunnel_id = htons(_this->peer_tunnel_id)(__uint16_t)(__builtin_constant_p(_this->peer_tunnel_id) ? (__uint16_t)(((__uint16_t)(_this->peer_tunnel_id) & 0xffU ) << 8 | ((__uint16_t)(_this->peer_tunnel_id) & 0xff00U ) >> 8) : __swap16md(_this->peer_tunnel_id)); |
| 1093 | hdr->session_id = htons(call_id)(__uint16_t)(__builtin_constant_p(call_id) ? (__uint16_t)(((__uint16_t )(call_id) & 0xffU) << 8 | ((__uint16_t)(call_id) & 0xff00U) >> 8) : __swap16md(call_id)); |
| 1094 | |
| 1095 | hdr->s = 1; |
| 1096 | seq = _this->snd_nxt; |
| 1097 | hdr->ns = htons(seq)(__uint16_t)(__builtin_constant_p(seq) ? (__uint16_t)(((__uint16_t )(seq) & 0xffU) << 8 | ((__uint16_t)(seq) & 0xff00U ) >> 8) : __swap16md(seq)); |
| 1098 | hdr->nr = htons(_this->rcv_nxt)(__uint16_t)(__builtin_constant_p(_this->rcv_nxt) ? (__uint16_t )(((__uint16_t)(_this->rcv_nxt) & 0xffU) << 8 | ( (__uint16_t)(_this->rcv_nxt) & 0xff00U) >> 8) : __swap16md (_this->rcv_nxt)); |
| 1099 | |
| 1100 | if (bytebuffer_remaining(bytebuf) > sizeof(struct l2tp_header)) |
| 1101 | /* Not ZLB */ |
| 1102 | _this->snd_nxt++; |
| 1103 | |
| 1104 | if (!l2tp_ctrl_in_peer_window(_this, seq)) |
| 1105 | return (0); |
| 1106 | |
| 1107 | L2TP_CTRL_DBG((_this, DEBUG_LEVEL_2, |
| 1108 | "SEND C ns=%u nr=%u snd_nxt=%u snd_una=%u rcv_nxt=%u ", |
| 1109 | ntohs(hdr->ns), htons(hdr->nr), |
| 1110 | _this->snd_nxt, _this->snd_una, _this->rcv_nxt)); |
| 1111 | |
| 1112 | if (L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->ctrl_out_pktdump != 0) { |
| 1113 | l2tpd_log(_this->l2tpd, LOG_DEBUG7, |
| 1114 | "L2TP Control output packet dump"); |
| 1115 | show_hd(debug_get_debugfp(), bytebuffer_pointer(bytebuf), |
| 1116 | bytebuffer_remaining(bytebuf)); |
| 1117 | } |
| 1118 | |
| 1119 | if ((rval = l2tp_ctrl_send(_this, bytebuffer_pointer(bytebuf), |
| 1120 | bytebuffer_remaining(bytebuf))) < 0) { |
| 1121 | L2TP_CTRL_DBG((_this, LOG_DEBUG, "sendto() failed: %m")); |
| 1122 | } |
| 1123 | |
| 1124 | _this->snd_lastnr = _this->rcv_nxt; |
| 1125 | _this->last_snd_ctrl = curr_time; |
| 1126 | _this->snd_last = seq; |
| 1127 | |
| 1128 | return (rval == bytebuffer_remaining(bytebuf))? 0 : 1; |
| 1129 | } |
| 1130 | |
| 1131 | /* |
| 1132 | * receiver SCCRQ |
| 1133 | */ |
| 1134 | static int |
| 1135 | l2tp_ctrl_recv_SCCRQ(l2tp_ctrl *_this, u_char *pkt, int pktlen, l2tpd *_l2tpd, |
| 1136 | struct sockaddr *peer) |
| 1137 | { |
| 1138 | int avpsz, len, protover, protorev, firmrev, result; |
| 1139 | struct l2tp_avp *avp; |
| 1140 | char host[NI_MAXHOST256], serv[NI_MAXSERV32]; |
| 1141 | char buf[L2TP_AVP_MAXSIZ1024], emes[256], hostname[256], vendorname[256]; |
| 1142 | |
| 1143 | result = L2TP_STOP_CCN_RCODE_GENERAL_ERROR2; |
| 1144 | strlcpy(hostname, "(no hostname)", sizeof(hostname)); |
| 1145 | strlcpy(vendorname, "(no vendorname)", sizeof(vendorname)); |
| 1146 | |
| 1147 | _this->peer_winsz = 4; /* default is 4 in RFC 2661 */ |
| 1148 | firmrev = 0; |
| 1149 | protover = 0; |
| 1150 | protorev = 0; |
| 1151 | avp = (struct l2tp_avp *)buf; |
| 1152 | while (pktlen >= 6 && (avpsz = avp_enum(avp, pkt, pktlen, 1)) > 0) { |
| 1153 | pkt += avpsz; |
| 1154 | pktlen -= avpsz; |
| 1155 | if (avp->vendor_id != 0) { |
| 1156 | L2TP_CTRL_DBG((_this, LOG_DEBUG, |
| 1157 | "Received a Vendor-specific AVP vendor-id=%d " |
| 1158 | "type=%d", avp->vendor_id, avp->attr_type)); |
| 1159 | continue; |
| 1160 | } |
| 1161 | switch (avp->attr_type) { |
| 1162 | case L2TP_AVP_TYPE_MESSAGE_TYPE0: |
| 1163 | AVP_SIZE_CHECK(avp, ==, 8)do { if (!((avp)->length == (8))) { snprintf(emes, sizeof( emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (8)); goto size_check_failed ; } } while ( 0); |
| 1164 | continue; |
| 1165 | case L2TP_AVP_TYPE_PROTOCOL_VERSION2: |
| 1166 | AVP_SIZE_CHECK(avp, ==, 8)do { if (!((avp)->length == (8))) { snprintf(emes, sizeof( emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (8)); goto size_check_failed ; } } while ( 0); |
| 1167 | protover = avp->attr_value[0]; |
| 1168 | protorev = avp->attr_value[1]; |
| 1169 | |
| 1170 | if (protover != L2TP_RFC2661_VERSION1 || |
| 1171 | protorev != L2TP_RFC2661_REVISION0) { |
| 1172 | result = L2TP_STOP_CCN_RCODE_GENERAL_ERROR2; |
| 1173 | snprintf(emes, sizeof(emes), |
| 1174 | "Peer's protocol version is not supported:" |
| 1175 | " %d.%d", protover, protorev); |
| 1176 | goto not_acceptable; |
| 1177 | } |
| 1178 | continue; |
| 1179 | case L2TP_AVP_TYPE_FRAMING_CAPABILITIES3: |
| 1180 | AVP_SIZE_CHECK(avp, ==, 10)do { if (!((avp)->length == (10))) { snprintf(emes, sizeof (emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (10)); goto size_check_failed ; } } while ( 0); |
| 1181 | if ((avp_get_val32(avp) & L2TP_FRAMING_CAP_FLAGS_SYNC0x00000001) |
| 1182 | == 0) { |
| 1183 | L2TP_CTRL_DBG((_this, LOG_DEBUG, "Peer doesn't " |
| 1184 | "support synchronous framing")); |
| 1185 | } |
| 1186 | continue; |
| 1187 | case L2TP_AVP_TYPE_BEARER_CAPABILITIES4: |
| 1188 | AVP_SIZE_CHECK(avp, ==, 10)do { if (!((avp)->length == (10))) { snprintf(emes, sizeof (emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (10)); goto size_check_failed ; } } while ( 0); |
| 1189 | continue; |
| 1190 | case L2TP_AVP_TYPE_TIE_BREAKER5: |
| 1191 | AVP_SIZE_CHECK(avp, ==, 14)do { if (!((avp)->length == (14))) { snprintf(emes, sizeof (emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (14)); goto size_check_failed ; } } while ( 0); |
| 1192 | /* |
| 1193 | * As the implementation never send SCCRQ, |
| 1194 | * the peer is always winner |
| 1195 | */ |
| 1196 | continue; |
| 1197 | case L2TP_AVP_TYPE_FIRMWARE_REVISION6: |
| 1198 | AVP_SIZE_CHECK(avp, >=, 6)do { if (!((avp)->length >= (6))) { snprintf(emes, sizeof (emes), "invalid packet size %s %d" ">=" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (6)); goto size_check_failed ; } } while ( 0); |
| 1199 | firmrev = avp_get_val16(avp); |
| 1200 | continue; |
| 1201 | case L2TP_AVP_TYPE_HOST_NAME7: |
| 1202 | AVP_SIZE_CHECK(avp, >, 4)do { if (!((avp)->length > (4))) { snprintf(emes, sizeof (emes), "invalid packet size %s %d" ">" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (4)); goto size_check_failed ; } } while ( 0); |
| 1203 | len = MINIMUM(sizeof(hostname) - 1, avp->length - 6)(((sizeof(hostname) - 1) < (avp->length - 6)) ? (sizeof (hostname) - 1) : (avp->length - 6)); |
| 1204 | memcpy(hostname, avp->attr_value, len); |
| 1205 | hostname[len] = '\0'; |
| 1206 | continue; |
| 1207 | case L2TP_AVP_TYPE_VENDOR_NAME8: |
| 1208 | AVP_SIZE_CHECK(avp, >, 4)do { if (!((avp)->length > (4))) { snprintf(emes, sizeof (emes), "invalid packet size %s %d" ">" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (4)); goto size_check_failed ; } } while ( 0); |
| 1209 | len = MINIMUM(sizeof(vendorname) - 1, avp->length - 6)(((sizeof(vendorname) - 1) < (avp->length - 6)) ? (sizeof (vendorname) - 1) : (avp->length - 6)); |
| 1210 | memcpy(vendorname, avp->attr_value, len); |
| 1211 | vendorname[len] = '\0'; |
| 1212 | continue; |
| 1213 | case L2TP_AVP_TYPE_ASSINGED_TUNNEL_ID9: |
| 1214 | AVP_SIZE_CHECK(avp, ==, 8)do { if (!((avp)->length == (8))) { snprintf(emes, sizeof( emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (8)); goto size_check_failed ; } } while ( 0); |
| 1215 | _this->peer_tunnel_id = avp_get_val16(avp); |
| 1216 | continue; |
| 1217 | case L2TP_AVP_TYPE_RECV_WINDOW_SIZE10: |
| 1218 | AVP_SIZE_CHECK(avp, ==, 8)do { if (!((avp)->length == (8))) { snprintf(emes, sizeof( emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (8)); goto size_check_failed ; } } while ( 0); |
| 1219 | _this->peer_winsz = avp_get_val16(avp); |
| 1220 | continue; |
| 1221 | } |
| 1222 | if (avp->is_mandatory) { |
| 1223 | l2tp_ctrl_log(_this, LOG_WARNING4, |
| 1224 | "Received AVP (%s/%d) is not supported, but it's " |
| 1225 | "mandatory", avp_attr_type_string(avp->attr_type), |
| 1226 | avp->attr_type); |
| 1227 | #ifdef L2TP_CTRL_DEBUG |
| 1228 | } else { |
| 1229 | L2TP_CTRL_DBG((_this, LOG_DEBUG, |
| 1230 | "AVP (%s/%d) is not handled", |
| 1231 | avp_attr_type_string(avp->attr_type), |
| 1232 | avp->attr_type)); |
| 1233 | #endif |
| 1234 | } |
| 1235 | } |
| 1236 | if (getnameinfo((struct sockaddr *)&_this->peer, _this->peer.ss_len, |
| 1237 | host, sizeof(host), serv, sizeof(serv), |
| 1238 | NI_NUMERICHOST1 | NI_NUMERICSERV2 | NI_DGRAM16) != 0) { |
| 1239 | l2tp_ctrl_log(_this, LOG_ERR3, |
| 1240 | "getnameinfo() failed at %s(): %m", __func__); |
| 1241 | strlcpy(host, "error", sizeof(host)); |
| 1242 | strlcpy(serv, "error", sizeof(serv)); |
| 1243 | } |
| 1244 | l2tp_ctrl_log(_this, LOG_NOTICE5, "logtype=Started RecvSCCRQ " |
| 1245 | "from=%s:%s/udp tunnel_id=%u/%u protocol=%d.%d winsize=%d " |
| 1246 | "hostname=%s vendor=%s firm=%04X", host, serv, _this->tunnel_id, |
| 1247 | _this->peer_tunnel_id, protover, protorev, _this->peer_winsz, |
| 1248 | hostname, vendorname, firmrev); |
| 1249 | |
| 1250 | if (_this->peer_winsz == 0) |
| 1251 | _this->peer_winsz = 1; |
| 1252 | |
| 1253 | return 0; |
| 1254 | not_acceptable: |
| 1255 | size_check_failed: |
| 1256 | l2tp_ctrl_log(_this, LOG_ERR3, "Received bad SCCRQ: %s", emes); |
| 1257 | l2tp_ctrl_stop(_this, result); |
| 1258 | |
| 1259 | return 1; |
| 1260 | } |
| 1261 | |
| 1262 | /* |
| 1263 | * send StopCCN |
| 1264 | */ |
| 1265 | static int |
| 1266 | l2tp_ctrl_send_StopCCN(l2tp_ctrl *_this, int result) |
| 1267 | { |
| 1268 | struct l2tp_avp *avp; |
| 1269 | char buf[L2TP_AVP_MAXSIZ1024]; |
| 1270 | bytebuffer *bytebuf; |
| 1271 | |
| 1272 | if ((bytebuf = l2tp_ctrl_prepare_snd_buffer(_this, 1)) == NULL((void*)0)) { |
| 1273 | l2tp_ctrl_log(_this, LOG_ERR3, |
| 1274 | "sending StopCCN failed: no buffer."); |
| 1275 | return -1; |
| 1276 | } |
| 1277 | avp = (struct l2tp_avp *)buf; |
| 1278 | |
| 1279 | /* Message Type = StopCCN */ |
| 1280 | memset(avp, 0, sizeof(*avp)); |
| 1281 | avp->is_mandatory = 1; |
| 1282 | avp->attr_type = L2TP_AVP_TYPE_MESSAGE_TYPE0; |
| 1283 | avp_set_val16(avp, L2TP_AVP_MESSAGE_TYPE_StopCCN4); |
| 1284 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1285 | |
| 1286 | /* Assigned Tunnel Id */ |
| 1287 | memset(avp, 0, sizeof(*avp)); |
| 1288 | avp->is_mandatory = 1; |
| 1289 | avp->attr_type = L2TP_AVP_TYPE_ASSINGED_TUNNEL_ID9; |
| 1290 | avp_set_val16(avp, _this->tunnel_id); |
| 1291 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1292 | |
| 1293 | /* Result Code */ |
| 1294 | memset(avp, 0, sizeof(*avp)); |
| 1295 | avp->is_mandatory = 1; |
| 1296 | avp->attr_type = L2TP_AVP_TYPE_RESULT_CODE1; |
| 1297 | avp_set_val16(avp, result); |
| 1298 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1299 | |
| 1300 | if (l2tp_ctrl_send_packet(_this, 0, bytebuf) != 0) { |
| 1301 | l2tp_ctrl_log(_this, LOG_ERR3, "sending StopCCN failed"); |
| 1302 | return - 1; |
| 1303 | } |
| 1304 | l2tp_ctrl_log(_this, LOG_INFO6, "SendStopCCN result=%d", result); |
| 1305 | |
| 1306 | return 0; |
| 1307 | } |
| 1308 | |
| 1309 | /* |
| 1310 | * Receiver StopCCN |
| 1311 | */ |
| 1312 | static int |
| 1313 | l2tp_ctrl_recv_StopCCN(l2tp_ctrl *_this, u_char *pkt, int pktlen) |
| 1314 | { |
| 1315 | int result, error, avpsz, len; |
| 1316 | uint16_t tunid; |
| 1317 | struct l2tp_avp *avp; |
| 1318 | char buf[L2TP_AVP_MAXSIZ1024 + 16], emes[256], pmes[256]; |
| 1319 | |
| 1320 | result = 0; |
| 1321 | error = 0; |
| 1322 | tunid = 0; |
| 1323 | pmes[0] = '\0'; |
| 1324 | avp = (struct l2tp_avp *)buf; |
| 1325 | while (pktlen >= 6 && (avpsz = avp_enum(avp, pkt, pktlen, 1)) > 0) { |
| 1326 | pkt += avpsz; |
| 1327 | pktlen -= avpsz; |
| 1328 | if (avp->vendor_id != 0) { |
| 1329 | L2TP_CTRL_DBG((_this, LOG_DEBUG, |
| 1330 | "Received a Vendor-specific AVP vendor-id=%d " |
| 1331 | "type=%d", avp->vendor_id, avp->attr_type)); |
| 1332 | continue; |
| 1333 | } |
| 1334 | if (avp->is_hidden != 0) { |
| 1335 | l2tp_ctrl_log(_this, LOG_WARNING4, |
| 1336 | "Received AVP (%s/%d) is hidden. But we don't " |
| 1337 | "share secret.", |
| 1338 | avp_attr_type_string(avp->attr_type), |
| 1339 | avp->attr_type); |
| 1340 | if (avp->is_mandatory != 0) { |
| 1341 | l2tp_ctrl_stop(_this, |
| 1342 | L2TP_STOP_CCN_RCODE_GENERAL_ERROR2 | |
| 1343 | L2TP_ECODE_UNKNOWN_MANDATORY_AVP8); |
| 1344 | return 1; |
| 1345 | } |
| 1346 | continue; |
| 1347 | } |
| 1348 | switch (avp->attr_type) { |
| 1349 | case L2TP_AVP_TYPE_MESSAGE_TYPE0: |
| 1350 | AVP_SIZE_CHECK(avp, ==, 8)do { if (!((avp)->length == (8))) { snprintf(emes, sizeof( emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (8)); goto size_check_failed ; } } while ( 0); |
| 1351 | continue; |
| 1352 | case L2TP_AVP_TYPE_RESULT_CODE1: |
| 1353 | AVP_SIZE_CHECK(avp, >=, 8)do { if (!((avp)->length >= (8))) { snprintf(emes, sizeof (emes), "invalid packet size %s %d" ">=" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (8)); goto size_check_failed ; } } while ( 0); |
| 1354 | result = avp->attr_value[0] << 8 | avp->attr_value[1]; |
| 1355 | if (avp->length >= 10) { |
| 1356 | error = avp->attr_value[2] << 8 | |
| 1357 | avp->attr_value[3]; |
| 1358 | len = avp->length - 12; |
| 1359 | if (len > 0) { |
| 1360 | len = MINIMUM(len, sizeof(pmes) - 1)(((len) < (sizeof(pmes) - 1)) ? (len) : (sizeof(pmes) - 1) ); |
| 1361 | memcpy(pmes, &avp->attr_value[4], len); |
| 1362 | pmes[len] = '\0'; |
| 1363 | } |
| 1364 | } |
| 1365 | continue; |
| 1366 | case L2TP_AVP_TYPE_ASSINGED_TUNNEL_ID9: |
| 1367 | AVP_SIZE_CHECK(avp, ==, 8)do { if (!((avp)->length == (8))) { snprintf(emes, sizeof( emes), "invalid packet size %s %d" "==" "%d)", avp_attr_type_string ((avp)->attr_type), (avp)->length, (8)); goto size_check_failed ; } } while ( 0); |
| 1368 | tunid = avp_get_val16(avp); |
| 1369 | continue; |
| 1370 | default: |
| 1371 | if (avp->is_mandatory != 0) { |
| 1372 | l2tp_ctrl_log(_this, LOG_WARNING4, |
| 1373 | "Received AVP (%s/%d) is not supported, " |
| 1374 | "but it's mandatory", |
| 1375 | avp_attr_type_string(avp->attr_type), |
| 1376 | avp->attr_type); |
| 1377 | #ifdef L2TP_CTRL_DEBUG |
| 1378 | } else { |
| 1379 | L2TP_CTRL_DBG((_this, LOG_DEBUG, |
| 1380 | "AVP (%s/%d) is not handled", |
| 1381 | avp_attr_type_string(avp->attr_type), |
| 1382 | avp->attr_type)); |
| 1383 | #endif |
| 1384 | } |
| 1385 | } |
| 1386 | } |
| 1387 | |
| 1388 | if (result == L2TP_CDN_RCODE_ERROR_CODE2 && |
| 1389 | error == L2TP_ECODE_NO_RESOURCE4) { |
| 1390 | /* |
| 1391 | * Memo: |
| 1392 | * This state may be happen in following state. |
| 1393 | * - lots of connect/disconnect by long-running |
| 1394 | * windows2000, sometimes it fall to this state. |
| 1395 | * Once it fall to here, connection will fail till |
| 1396 | * the windows rebooted |
| 1397 | */ |
| 1398 | l2tp_ctrl_log(_this, LOG_WARNING4, |
| 1399 | "Peer indicates \"No Resource\" error."); |
| 1400 | } |
| 1401 | |
| 1402 | l2tp_ctrl_log(_this, LOG_INFO6, "RecvStopCCN result=%s/%u " |
| 1403 | "error=%s/%u tunnel_id=%u message=\"%s\"", |
| 1404 | l2tp_stopccn_rcode_string(result), result, |
| 1405 | l2tp_ecode_string(error), error, tunid, pmes); |
| 1406 | |
| 1407 | return 0; |
| 1408 | |
| 1409 | size_check_failed: |
| 1410 | l2tp_ctrl_log(_this, LOG_ERR3, "Received bad StopCCN: %s", emes); |
| 1411 | |
| 1412 | return -1; |
| 1413 | } |
| 1414 | |
| 1415 | /* |
| 1416 | * send SCCRP |
| 1417 | */ |
| 1418 | static void |
| 1419 | l2tp_ctrl_send_SCCRP(l2tp_ctrl *_this) |
| 1420 | { |
| 1421 | int len; |
| 1422 | struct l2tp_avp *avp; |
| 1423 | char buf[L2TP_AVP_MAXSIZ1024], hbuf[HOST_NAME_MAX255+1]; |
| 1424 | const char *val; |
| 1425 | bytebuffer *bytebuf; |
| 1426 | |
| 1427 | if ((bytebuf = l2tp_ctrl_prepare_snd_buffer(_this, 1)) == NULL((void*)0)) { |
| 1428 | l2tp_ctrl_log(_this, LOG_ERR3, |
| 1429 | "sending SCCRP failed: no buffer."); |
| 1430 | return; |
| 1431 | } |
| 1432 | avp = (struct l2tp_avp *)buf; |
| 1433 | |
| 1434 | /* Message Type = SCCRP */ |
| 1435 | memset(avp, 0, sizeof(*avp)); |
| 1436 | avp->is_mandatory = 1; |
| 1437 | avp->attr_type = L2TP_AVP_TYPE_MESSAGE_TYPE0; |
| 1438 | avp_set_val16(avp, L2TP_AVP_MESSAGE_TYPE_SCCRP2); |
| 1439 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1440 | |
| 1441 | /* Protocol Version = 1.0 */ |
| 1442 | memset(avp, 0, sizeof(*avp)); |
| 1443 | avp->is_mandatory = 1; |
| 1444 | avp->attr_type = L2TP_AVP_TYPE_PROTOCOL_VERSION2; |
| 1445 | avp->attr_value[0] = L2TP_RFC2661_VERSION1; |
| 1446 | avp->attr_value[1] = L2TP_RFC2661_REVISION0; |
| 1447 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1448 | |
| 1449 | /* Framing Capability = Async */ |
| 1450 | memset(avp, 0, sizeof(*avp)); |
| 1451 | avp->is_mandatory = 1; |
| 1452 | avp->attr_type = L2TP_AVP_TYPE_FRAMING_CAPABILITIES3; |
| 1453 | avp_set_val32(avp, L2TP_FRAMING_CAP_FLAGS_SYNC0x00000001); |
| 1454 | bytebuf_add_avp(bytebuf, avp, 4); |
| 1455 | |
| 1456 | /* Host Name */ |
| 1457 | memset(avp, 0, sizeof(*avp)); |
| 1458 | avp->is_mandatory = 1; |
| 1459 | avp->attr_type = L2TP_AVP_TYPE_HOST_NAME7; |
| 1460 | if ((val = L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->hostname) == NULL((void*)0)) { |
| 1461 | gethostname(hbuf, sizeof(hbuf)); |
| 1462 | val = hbuf; |
| 1463 | } |
| 1464 | len = strlen(val); |
| 1465 | memcpy(avp->attr_value, val, len); |
| 1466 | bytebuf_add_avp(bytebuf, avp, len); |
| 1467 | |
| 1468 | /* Assigned Tunnel Id */ |
| 1469 | memset(avp, 0, sizeof(*avp)); |
| 1470 | avp->is_mandatory = 1; |
| 1471 | avp->attr_type = L2TP_AVP_TYPE_ASSINGED_TUNNEL_ID9; |
| 1472 | avp_set_val16(avp, _this->tunnel_id); |
| 1473 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1474 | |
| 1475 | /* Bearer Capability |
| 1476 | * This implementation never act as LAC. |
| 1477 | * |
| 1478 | memset(avp, 0, sizeof(*avp)); |
| 1479 | avp->is_mandatory = 1; |
| 1480 | avp->attr_type = L2TP_AVP_TYPE_BEARER_CAPABILITIES; |
| 1481 | avp_set_val32(avp, 0); |
| 1482 | bytebuf_add_avp(bytebuf, avp, 4); |
| 1483 | */ |
| 1484 | |
| 1485 | /* Firmware Revision */ |
| 1486 | memset(avp, 0, sizeof(*avp)); |
| 1487 | avp->is_mandatory = 0; |
| 1488 | avp->attr_type = L2TP_AVP_TYPE_FIRMWARE_REVISION6; |
| 1489 | avp->attr_value[0] = MAJOR_VERSION5; |
| 1490 | avp->attr_value[1] = MINOR_VERSION2; |
| 1491 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1492 | |
| 1493 | /* Vendor Name */ |
| 1494 | if ((val = L2TP_CTRL_CONF(_this)((l2tpd_listener *)slist_get(&(_this)->l2tpd->listener , (_this)->listener_index))->conf->vendor_name) != NULL((void*)0)) { |
| 1495 | memset(avp, 0, sizeof(*avp)); |
| 1496 | avp->is_mandatory = 0; |
| 1497 | avp->attr_type = L2TP_AVP_TYPE_VENDOR_NAME8; |
| 1498 | |
| 1499 | len = strlen(val); |
| 1500 | memcpy(avp->attr_value, val, len); |
| 1501 | bytebuf_add_avp(bytebuf, avp, len); |
| 1502 | } |
| 1503 | |
| 1504 | /* Window Size */ |
| 1505 | memset(avp, 0, sizeof(*avp)); |
| 1506 | avp->is_mandatory = 1; |
| 1507 | avp->attr_type = L2TP_AVP_TYPE_RECV_WINDOW_SIZE10; |
| 1508 | avp_set_val16(avp, _this->winsz); |
| 1509 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1510 | |
| 1511 | if ((l2tp_ctrl_send_packet(_this, 0, bytebuf)) != 0) { |
| 1512 | l2tp_ctrl_log(_this, LOG_ERR3, "sending SCCRP failed"); |
| 1513 | l2tp_ctrl_stop(_this, L2TP_STOP_CCN_RCODE_GENERAL1); |
| 1514 | return; |
| 1515 | } |
| 1516 | l2tp_ctrl_log(_this, LOG_INFO6, "SendSCCRP"); |
| 1517 | } |
| 1518 | |
| 1519 | static int |
| 1520 | l2tp_ctrl_send_HELLO(l2tp_ctrl *_this) |
| 1521 | { |
| 1522 | struct l2tp_avp *avp; |
| 1523 | char buf[L2TP_AVP_MAXSIZ1024]; |
| 1524 | bytebuffer *bytebuf; |
| 1525 | |
| 1526 | if ((bytebuf = l2tp_ctrl_prepare_snd_buffer(_this, 1)) == NULL((void*)0)) { |
| 1527 | l2tp_ctrl_log(_this, LOG_ERR3, |
| 1528 | "sending HELLO failed: no buffer."); |
| 1529 | return 1; |
| 1530 | } |
| 1531 | avp = (struct l2tp_avp *)buf; |
| 1532 | |
| 1533 | /* Message Type = HELLO */ |
| 1534 | memset(avp, 0, sizeof(*avp)); |
| 1535 | avp->is_mandatory = 1; |
| 1536 | avp->attr_type = L2TP_AVP_TYPE_MESSAGE_TYPE0; |
| 1537 | avp_set_val16(avp, L2TP_AVP_MESSAGE_TYPE_HELLO6); |
| 1538 | bytebuf_add_avp(bytebuf, avp, 2); |
| 1539 | |
| 1540 | if ((l2tp_ctrl_send_packet(_this, 0, bytebuf)) != 0) { |
| 1541 | l2tp_ctrl_log(_this, LOG_ERR3, "sending HELLO failed"); |
| 1542 | l2tp_ctrl_stop(_this, L2TP_STOP_CCN_RCODE_GENERAL1); |
| 1543 | return 1; |
| 1544 | } |
| 1545 | l2tp_ctrl_log(_this, LOG_DEBUG7, "SendHELLO"); |
| 1546 | |
| 1547 | return 0; |
| 1548 | } |
| 1549 | |
| 1550 | /* Send ZLB */ |
| 1551 | static int |
| 1552 | l2tp_ctrl_send_ZLB(l2tp_ctrl *_this) |
| 1553 | { |
| 1554 | int loglevel; |
| 1555 | |
| 1556 | loglevel = (_this->state == L2TP_CTRL_STATE_ESTABLISHED3) |
| 1557 | ? LOG_DEBUG7 : LOG_INFO6; |
| 1558 | l2tp_ctrl_log(_this, loglevel, "SendZLB"); |
| 1559 | bytebuffer_clear(_this->zlb_buffer); |
| 1560 | bytebuffer_put(_this->zlb_buffer, BYTEBUFFER_PUT_DIRECT, |
| 1561 | sizeof(struct l2tp_header)); |
| 1562 | |
| 1563 | return l2tp_ctrl_send_packet(_this, 0, _this->zlb_buffer); |
| 1564 | } |
| 1565 | |
| 1566 | /* |
| 1567 | * Utitlity |
| 1568 | */ |
| 1569 | |
| 1570 | /** |
| 1571 | * Prepare send buffer |
| 1572 | * @return return Null when the send buffer exceed Window. |
| 1573 | */ |
| 1574 | bytebuffer * |
| 1575 | l2tp_ctrl_prepare_snd_buffer(l2tp_ctrl *_this, int with_seq) |
| 1576 | { |
| 1577 | bytebuffer *bytebuf; |
| 1578 | |
| 1579 | L2TP_CTRL_ASSERT(_this != NULL); |
| 1580 | |
| 1581 | if (l2tp_ctrl_txwin_is_full(_this)) { |
| 1582 | l2tp_ctrl_log(_this, LOG_INFO6, "sending buffer is full."); |
| 1583 | return NULL((void*)0); |
| 1584 | } |
| 1585 | bytebuf = _this->snd_buffers[_this->snd_nxt % _this->snd_buffercnt]; |
| 1586 | bytebuffer_clear(bytebuf); |
| 1587 | if (with_seq) |
| 1588 | bytebuffer_put(bytebuf, BYTEBUFFER_PUT_DIRECT, |
| 1589 | sizeof(struct l2tp_header)); |
| 1590 | else |
| 1591 | bytebuffer_put(bytebuf, BYTEBUFFER_PUT_DIRECT, |
| 1592 | offsetof(struct l2tp_header, ns)__builtin_offsetof(struct l2tp_header, ns)); |
| 1593 | |
| 1594 | return bytebuf; |
| 1595 | } |
| 1596 | |
| 1597 | /** |
| 1598 | * return current state as strings |
| 1599 | */ |
| 1600 | static inline const char * |
| 1601 | l2tp_ctrl_state_string(l2tp_ctrl *_this) |
| 1602 | { |
| 1603 | switch (_this->state) { |
| 1604 | case L2TP_CTRL_STATE_IDLE0: return "idle"; |
| 1605 | case L2TP_CTRL_STATE_WAIT_CTL_CONN1: return "wait-ctl-conn"; |
| 1606 | case L2TP_CTRL_STATE_WAIT_CTL_REPLY2: return "wait-ctl-reply"; |
| 1607 | case L2TP_CTRL_STATE_ESTABLISHED3: return "established"; |
| 1608 | case L2TP_CTRL_STATE_CLEANUP_WAIT4: return "cleanup-wait"; |
| 1609 | } |
| 1610 | return "unknown"; |
| 1611 | } |
| 1612 | |
| 1613 | /* logging with the label of the l2tp instance. */ |
| 1614 | void |
| 1615 | l2tp_ctrl_log(l2tp_ctrl *_this, int prio, const char *fmt, ...) |
| 1616 | { |
| 1617 | char logbuf[BUFSIZ1024]; |
| 1618 | va_list ap; |
| 1619 | |
| 1620 | va_start(ap, fmt)__builtin_va_start(ap, fmt); |
| 1621 | #ifdef L2TPD_MULTIPLE |
| 1622 | snprintf(logbuf, sizeof(logbuf), "l2tpd id=%u ctrl=%u %s", |
| 1623 | _this->l2tpd->id, _this->id, fmt); |
| 1624 | #else |
| 1625 | snprintf(logbuf, sizeof(logbuf), "l2tpd ctrl=%u %s", _this->id, fmt); |
| 1626 | #endif |
| 1627 | vlog_printf(prio, logbuf, ap); |
| 1628 | va_end(ap)__builtin_va_end(ap); |
| 1629 | } |