Commit | Line | Data |
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60c778b2 | 1 | /* SCTP kernel implementation |
1da177e4 LT |
2 | * Copyright (c) 1999-2000 Cisco, Inc. |
3 | * Copyright (c) 1999-2001 Motorola, Inc. | |
4 | * Copyright (c) 2001-2002 International Business Machines, Corp. | |
5 | * Copyright (c) 2001 Intel Corp. | |
6 | * Copyright (c) 2001 Nokia, Inc. | |
7 | * Copyright (c) 2001 La Monte H.P. Yarroll | |
8 | * | |
60c778b2 | 9 | * This file is part of the SCTP kernel implementation |
1da177e4 LT |
10 | * |
11 | * This abstraction represents an SCTP endpoint. | |
12 | * | |
60c778b2 | 13 | * The SCTP implementation is free software; |
1da177e4 LT |
14 | * you can redistribute it and/or modify it under the terms of |
15 | * the GNU General Public License as published by | |
16 | * the Free Software Foundation; either version 2, or (at your option) | |
17 | * any later version. | |
18 | * | |
60c778b2 | 19 | * The SCTP implementation is distributed in the hope that it |
1da177e4 LT |
20 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
21 | * ************************ | |
22 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
23 | * See the GNU General Public License for more details. | |
24 | * | |
25 | * You should have received a copy of the GNU General Public License | |
4b2f13a2 JK |
26 | * along with GNU CC; see the file COPYING. If not, see |
27 | * <http://www.gnu.org/licenses/>. | |
1da177e4 LT |
28 | * |
29 | * Please send any bug reports or fixes you make to the | |
30 | * email address(es): | |
91705c61 | 31 | * lksctp developers <linux-sctp@vger.kernel.org> |
1da177e4 | 32 | * |
1da177e4 LT |
33 | * Written or modified by: |
34 | * La Monte H.P. Yarroll <piggy@acm.org> | |
35 | * Karl Knutson <karl@athena.chicago.il.us> | |
36 | * Jon Grimm <jgrimm@austin.ibm.com> | |
37 | * Daisy Chang <daisyc@us.ibm.com> | |
38 | * Dajiang Zhang <dajiang.zhang@nokia.com> | |
1da177e4 LT |
39 | */ |
40 | ||
41 | #include <linux/types.h> | |
1da177e4 LT |
42 | #include <linux/slab.h> |
43 | #include <linux/in.h> | |
44 | #include <linux/random.h> /* get_random_bytes() */ | |
45 | #include <linux/crypto.h> | |
46 | #include <net/sock.h> | |
47 | #include <net/ipv6.h> | |
48 | #include <net/sctp/sctp.h> | |
49 | #include <net/sctp/sm.h> | |
50 | ||
51 | /* Forward declarations for internal helpers. */ | |
c4028958 | 52 | static void sctp_endpoint_bh_rcv(struct work_struct *work); |
1da177e4 LT |
53 | |
54 | /* | |
55 | * Initialize the base fields of the endpoint structure. | |
56 | */ | |
57 | static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep, | |
3182cd84 | 58 | struct sock *sk, |
dd0fc66f | 59 | gfp_t gfp) |
1da177e4 | 60 | { |
e1fc3b14 | 61 | struct net *net = sock_net(sk); |
a29a5bd4 VY |
62 | struct sctp_hmac_algo_param *auth_hmacs = NULL; |
63 | struct sctp_chunks_param *auth_chunks = NULL; | |
64 | struct sctp_shared_key *null_key; | |
65 | int err; | |
66 | ||
b68dbcab VY |
67 | ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp); |
68 | if (!ep->digest) | |
69 | return NULL; | |
70 | ||
b14878cc VY |
71 | ep->auth_enable = net->sctp.auth_enable; |
72 | if (ep->auth_enable) { | |
a29a5bd4 VY |
73 | /* Allocate space for HMACS and CHUNKS authentication |
74 | * variables. There are arrays that we encode directly | |
75 | * into parameters to make the rest of the operations easier. | |
76 | */ | |
77 | auth_hmacs = kzalloc(sizeof(sctp_hmac_algo_param_t) + | |
78 | sizeof(__u16) * SCTP_AUTH_NUM_HMACS, gfp); | |
79 | if (!auth_hmacs) | |
80 | goto nomem; | |
81 | ||
82 | auth_chunks = kzalloc(sizeof(sctp_chunks_param_t) + | |
83 | SCTP_NUM_CHUNK_TYPES, gfp); | |
84 | if (!auth_chunks) | |
85 | goto nomem; | |
86 | ||
87 | /* Initialize the HMACS parameter. | |
88 | * SCTP-AUTH: Section 3.3 | |
89 | * Every endpoint supporting SCTP chunk authentication MUST | |
90 | * support the HMAC based on the SHA-1 algorithm. | |
91 | */ | |
92 | auth_hmacs->param_hdr.type = SCTP_PARAM_HMAC_ALGO; | |
93 | auth_hmacs->param_hdr.length = | |
94 | htons(sizeof(sctp_paramhdr_t) + 2); | |
95 | auth_hmacs->hmac_ids[0] = htons(SCTP_AUTH_HMAC_ID_SHA1); | |
96 | ||
97 | /* Initialize the CHUNKS parameter */ | |
98 | auth_chunks->param_hdr.type = SCTP_PARAM_CHUNKS; | |
5e739d17 | 99 | auth_chunks->param_hdr.length = htons(sizeof(sctp_paramhdr_t)); |
a29a5bd4 VY |
100 | |
101 | /* If the Add-IP functionality is enabled, we must | |
102 | * authenticate, ASCONF and ASCONF-ACK chunks | |
103 | */ | |
e1fc3b14 | 104 | if (net->sctp.addip_enable) { |
a29a5bd4 VY |
105 | auth_chunks->chunks[0] = SCTP_CID_ASCONF; |
106 | auth_chunks->chunks[1] = SCTP_CID_ASCONF_ACK; | |
cb0dc77d AV |
107 | auth_chunks->param_hdr.length = |
108 | htons(sizeof(sctp_paramhdr_t) + 2); | |
a29a5bd4 VY |
109 | } |
110 | } | |
111 | ||
1da177e4 LT |
112 | /* Initialize the base structure. */ |
113 | /* What type of endpoint are we? */ | |
114 | ep->base.type = SCTP_EP_TYPE_SOCKET; | |
115 | ||
116 | /* Initialize the basic object fields. */ | |
117 | atomic_set(&ep->base.refcnt, 1); | |
0022d2dd | 118 | ep->base.dead = false; |
1da177e4 LT |
119 | |
120 | /* Create an input queue. */ | |
121 | sctp_inq_init(&ep->base.inqueue); | |
122 | ||
123 | /* Set its top-half handler */ | |
c4028958 | 124 | sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv); |
1da177e4 LT |
125 | |
126 | /* Initialize the bind addr area */ | |
127 | sctp_bind_addr_init(&ep->base.bind_addr, 0); | |
1da177e4 LT |
128 | |
129 | /* Remember who we are attached to. */ | |
130 | ep->base.sk = sk; | |
131 | sock_hold(ep->base.sk); | |
132 | ||
133 | /* Create the lists of associations. */ | |
134 | INIT_LIST_HEAD(&ep->asocs); | |
135 | ||
1da177e4 | 136 | /* Use SCTP specific send buffer space queues. */ |
e1fc3b14 | 137 | ep->sndbuf_policy = net->sctp.sndbuf_policy; |
4d93df0a | 138 | |
561b1733 | 139 | sk->sk_data_ready = sctp_data_ready; |
1da177e4 LT |
140 | sk->sk_write_space = sctp_write_space; |
141 | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); | |
142 | ||
049b3ff5 | 143 | /* Get the receive buffer policy for this endpoint */ |
e1fc3b14 | 144 | ep->rcvbuf_policy = net->sctp.rcvbuf_policy; |
049b3ff5 | 145 | |
1da177e4 | 146 | /* Initialize the secret key used with cookie. */ |
570617e7 | 147 | get_random_bytes(ep->secret_key, sizeof(ep->secret_key)); |
1da177e4 | 148 | |
a29a5bd4 VY |
149 | /* SCTP-AUTH extensions*/ |
150 | INIT_LIST_HEAD(&ep->endpoint_shared_keys); | |
81ce0dbc | 151 | null_key = sctp_auth_shkey_create(0, gfp); |
a29a5bd4 VY |
152 | if (!null_key) |
153 | goto nomem; | |
154 | ||
155 | list_add(&null_key->key_list, &ep->endpoint_shared_keys); | |
156 | ||
02582e9b | 157 | /* Allocate and initialize transorms arrays for supported HMACs. */ |
a29a5bd4 VY |
158 | err = sctp_auth_init_hmacs(ep, gfp); |
159 | if (err) | |
160 | goto nomem_hmacs; | |
161 | ||
162 | /* Add the null key to the endpoint shared keys list and | |
163 | * set the hmcas and chunks pointers. | |
164 | */ | |
165 | ep->auth_hmacs_list = auth_hmacs; | |
166 | ep->auth_chunk_list = auth_chunks; | |
167 | ||
1da177e4 | 168 | return ep; |
a29a5bd4 VY |
169 | |
170 | nomem_hmacs: | |
171 | sctp_auth_destroy_keys(&ep->endpoint_shared_keys); | |
172 | nomem: | |
173 | /* Free all allocations */ | |
174 | kfree(auth_hmacs); | |
175 | kfree(auth_chunks); | |
176 | kfree(ep->digest); | |
177 | return NULL; | |
178 | ||
1da177e4 LT |
179 | } |
180 | ||
181 | /* Create a sctp_endpoint with all that boring stuff initialized. | |
182 | * Returns NULL if there isn't enough memory. | |
183 | */ | |
dd0fc66f | 184 | struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp) |
1da177e4 LT |
185 | { |
186 | struct sctp_endpoint *ep; | |
187 | ||
188 | /* Build a local endpoint. */ | |
939cfa75 | 189 | ep = kzalloc(sizeof(*ep), gfp); |
1da177e4 LT |
190 | if (!ep) |
191 | goto fail; | |
939cfa75 | 192 | |
1da177e4 LT |
193 | if (!sctp_endpoint_init(ep, sk, gfp)) |
194 | goto fail_init; | |
ff2266cd | 195 | |
1da177e4 LT |
196 | SCTP_DBG_OBJCNT_INC(ep); |
197 | return ep; | |
198 | ||
199 | fail_init: | |
200 | kfree(ep); | |
201 | fail: | |
202 | return NULL; | |
203 | } | |
204 | ||
205 | /* Add an association to an endpoint. */ | |
206 | void sctp_endpoint_add_asoc(struct sctp_endpoint *ep, | |
207 | struct sctp_association *asoc) | |
208 | { | |
209 | struct sock *sk = ep->base.sk; | |
210 | ||
de76e695 VY |
211 | /* If this is a temporary association, don't bother |
212 | * since we'll be removing it shortly and don't | |
213 | * want anyone to find it anyway. | |
214 | */ | |
215 | if (asoc->temp) | |
216 | return; | |
217 | ||
1da177e4 LT |
218 | /* Now just add it to our list of asocs */ |
219 | list_add_tail(&asoc->asocs, &ep->asocs); | |
220 | ||
221 | /* Increment the backlog value for a TCP-style listening socket. */ | |
222 | if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING)) | |
223 | sk->sk_ack_backlog++; | |
224 | } | |
225 | ||
226 | /* Free the endpoint structure. Delay cleanup until | |
227 | * all users have released their reference count on this structure. | |
228 | */ | |
229 | void sctp_endpoint_free(struct sctp_endpoint *ep) | |
230 | { | |
0022d2dd | 231 | ep->base.dead = true; |
cfdeef32 VY |
232 | |
233 | ep->base.sk->sk_state = SCTP_SS_CLOSED; | |
234 | ||
235 | /* Unlink this endpoint, so we can't find it again! */ | |
236 | sctp_unhash_endpoint(ep); | |
237 | ||
1da177e4 LT |
238 | sctp_endpoint_put(ep); |
239 | } | |
240 | ||
241 | /* Final destructor for endpoint. */ | |
242 | static void sctp_endpoint_destroy(struct sctp_endpoint *ep) | |
243 | { | |
0a2fbac1 | 244 | struct sock *sk; |
1da177e4 | 245 | |
bb33381d DB |
246 | if (unlikely(!ep->base.dead)) { |
247 | WARN(1, "Attempt to destroy undead endpoint %p!\n", ep); | |
248 | return; | |
249 | } | |
1da177e4 | 250 | |
b68dbcab VY |
251 | /* Free the digest buffer */ |
252 | kfree(ep->digest); | |
253 | ||
a29a5bd4 VY |
254 | /* SCTP-AUTH: Free up AUTH releated data such as shared keys |
255 | * chunks and hmacs arrays that were allocated | |
256 | */ | |
257 | sctp_auth_destroy_keys(&ep->endpoint_shared_keys); | |
258 | kfree(ep->auth_hmacs_list); | |
259 | kfree(ep->auth_chunk_list); | |
260 | ||
261 | /* AUTH - Free any allocated HMAC transform containers */ | |
262 | sctp_auth_destroy_hmacs(ep->auth_hmacs); | |
263 | ||
1da177e4 LT |
264 | /* Cleanup. */ |
265 | sctp_inq_free(&ep->base.inqueue); | |
266 | sctp_bind_addr_free(&ep->base.bind_addr); | |
267 | ||
570617e7 | 268 | memset(ep->secret_key, 0, sizeof(ep->secret_key)); |
b5c37fe6 | 269 | |
1da177e4 | 270 | /* Give up our hold on the sock. */ |
0a2fbac1 DB |
271 | sk = ep->base.sk; |
272 | if (sk != NULL) { | |
273 | /* Remove and free the port */ | |
274 | if (sctp_sk(sk)->bind_hash) | |
275 | sctp_put_port(sk); | |
276 | ||
277 | sock_put(sk); | |
278 | } | |
1da177e4 | 279 | |
ff2266cd DB |
280 | kfree(ep); |
281 | SCTP_DBG_OBJCNT_DEC(ep); | |
1da177e4 LT |
282 | } |
283 | ||
284 | /* Hold a reference to an endpoint. */ | |
285 | void sctp_endpoint_hold(struct sctp_endpoint *ep) | |
286 | { | |
287 | atomic_inc(&ep->base.refcnt); | |
288 | } | |
289 | ||
290 | /* Release a reference to an endpoint and clean up if there are | |
291 | * no more references. | |
292 | */ | |
293 | void sctp_endpoint_put(struct sctp_endpoint *ep) | |
294 | { | |
295 | if (atomic_dec_and_test(&ep->base.refcnt)) | |
296 | sctp_endpoint_destroy(ep); | |
297 | } | |
298 | ||
299 | /* Is this the endpoint we are looking for? */ | |
300 | struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep, | |
4cdadcbc | 301 | struct net *net, |
1da177e4 LT |
302 | const union sctp_addr *laddr) |
303 | { | |
559cf710 | 304 | struct sctp_endpoint *retval = NULL; |
1da177e4 | 305 | |
4cdadcbc EB |
306 | if ((htons(ep->base.bind_addr.port) == laddr->v4.sin_port) && |
307 | net_eq(sock_net(ep->base.sk), net)) { | |
1da177e4 | 308 | if (sctp_bind_addr_match(&ep->base.bind_addr, laddr, |
559cf710 | 309 | sctp_sk(ep->base.sk))) |
1da177e4 | 310 | retval = ep; |
1da177e4 LT |
311 | } |
312 | ||
1da177e4 LT |
313 | return retval; |
314 | } | |
315 | ||
316 | /* Find the association that goes with this chunk. | |
317 | * We do a linear search of the associations for this endpoint. | |
318 | * We return the matching transport address too. | |
319 | */ | |
320 | static struct sctp_association *__sctp_endpoint_lookup_assoc( | |
321 | const struct sctp_endpoint *ep, | |
322 | const union sctp_addr *paddr, | |
323 | struct sctp_transport **transport) | |
324 | { | |
123ed979 | 325 | struct sctp_association *asoc = NULL; |
deb85a6e | 326 | struct sctp_association *tmp; |
123ed979 VY |
327 | struct sctp_transport *t = NULL; |
328 | struct sctp_hashbucket *head; | |
329 | struct sctp_ep_common *epb; | |
330 | int hash; | |
1da177e4 | 331 | int rport; |
1da177e4 | 332 | |
123ed979 | 333 | *transport = NULL; |
deb85a6e VY |
334 | |
335 | /* If the local port is not set, there can't be any associations | |
336 | * on this endpoint. | |
337 | */ | |
338 | if (!ep->base.bind_addr.port) | |
339 | goto out; | |
340 | ||
cd4ff034 | 341 | rport = ntohs(paddr->v4.sin_port); |
1da177e4 | 342 | |
4110cc25 EB |
343 | hash = sctp_assoc_hashfn(sock_net(ep->base.sk), ep->base.bind_addr.port, |
344 | rport); | |
123ed979 VY |
345 | head = &sctp_assoc_hashtable[hash]; |
346 | read_lock(&head->lock); | |
b67bfe0d | 347 | sctp_for_each_hentry(epb, &head->chain) { |
deb85a6e VY |
348 | tmp = sctp_assoc(epb); |
349 | if (tmp->ep != ep || rport != tmp->peer.port) | |
350 | continue; | |
123ed979 | 351 | |
deb85a6e | 352 | t = sctp_assoc_lookup_paddr(tmp, paddr); |
123ed979 | 353 | if (t) { |
deb85a6e | 354 | asoc = tmp; |
123ed979 VY |
355 | *transport = t; |
356 | break; | |
1da177e4 LT |
357 | } |
358 | } | |
123ed979 | 359 | read_unlock(&head->lock); |
deb85a6e | 360 | out: |
123ed979 | 361 | return asoc; |
1da177e4 LT |
362 | } |
363 | ||
364 | /* Lookup association on an endpoint based on a peer address. BH-safe. */ | |
365 | struct sctp_association *sctp_endpoint_lookup_assoc( | |
366 | const struct sctp_endpoint *ep, | |
367 | const union sctp_addr *paddr, | |
368 | struct sctp_transport **transport) | |
369 | { | |
370 | struct sctp_association *asoc; | |
371 | ||
79b91130 | 372 | local_bh_disable(); |
1da177e4 | 373 | asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport); |
79b91130 | 374 | local_bh_enable(); |
1da177e4 LT |
375 | |
376 | return asoc; | |
377 | } | |
378 | ||
379 | /* Look for any peeled off association from the endpoint that matches the | |
380 | * given peer address. | |
381 | */ | |
382 | int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep, | |
383 | const union sctp_addr *paddr) | |
384 | { | |
1da177e4 LT |
385 | struct sctp_sockaddr_entry *addr; |
386 | struct sctp_bind_addr *bp; | |
4110cc25 | 387 | struct net *net = sock_net(ep->base.sk); |
1da177e4 | 388 | |
1da177e4 | 389 | bp = &ep->base.bind_addr; |
559cf710 VY |
390 | /* This function is called with the socket lock held, |
391 | * so the address_list can not change. | |
392 | */ | |
393 | list_for_each_entry(addr, &bp->address_list, list) { | |
4110cc25 | 394 | if (sctp_has_association(net, &addr->a, paddr)) |
1da177e4 | 395 | return 1; |
1da177e4 | 396 | } |
1da177e4 LT |
397 | |
398 | return 0; | |
399 | } | |
400 | ||
401 | /* Do delayed input processing. This is scheduled by sctp_rcv(). | |
402 | * This may be called on BH or task time. | |
403 | */ | |
c4028958 | 404 | static void sctp_endpoint_bh_rcv(struct work_struct *work) |
1da177e4 | 405 | { |
c4028958 DH |
406 | struct sctp_endpoint *ep = |
407 | container_of(work, struct sctp_endpoint, | |
408 | base.inqueue.immediate); | |
1da177e4 LT |
409 | struct sctp_association *asoc; |
410 | struct sock *sk; | |
55e26eb9 | 411 | struct net *net; |
1da177e4 LT |
412 | struct sctp_transport *transport; |
413 | struct sctp_chunk *chunk; | |
414 | struct sctp_inq *inqueue; | |
415 | sctp_subtype_t subtype; | |
416 | sctp_state_t state; | |
417 | int error = 0; | |
42b2aa86 | 418 | int first_time = 1; /* is this the first time through the loop */ |
1da177e4 LT |
419 | |
420 | if (ep->base.dead) | |
421 | return; | |
422 | ||
423 | asoc = NULL; | |
424 | inqueue = &ep->base.inqueue; | |
425 | sk = ep->base.sk; | |
55e26eb9 | 426 | net = sock_net(sk); |
1da177e4 LT |
427 | |
428 | while (NULL != (chunk = sctp_inq_pop(inqueue))) { | |
429 | subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type); | |
430 | ||
bbd0d598 VY |
431 | /* If the first chunk in the packet is AUTH, do special |
432 | * processing specified in Section 6.3 of SCTP-AUTH spec | |
433 | */ | |
434 | if (first_time && (subtype.chunk == SCTP_CID_AUTH)) { | |
435 | struct sctp_chunkhdr *next_hdr; | |
436 | ||
437 | next_hdr = sctp_inq_peek(inqueue); | |
438 | if (!next_hdr) | |
439 | goto normal; | |
440 | ||
441 | /* If the next chunk is COOKIE-ECHO, skip the AUTH | |
442 | * chunk while saving a pointer to it so we can do | |
443 | * Authentication later (during cookie-echo | |
444 | * processing). | |
445 | */ | |
446 | if (next_hdr->type == SCTP_CID_COOKIE_ECHO) { | |
447 | chunk->auth_chunk = skb_clone(chunk->skb, | |
448 | GFP_ATOMIC); | |
449 | chunk->auth = 1; | |
450 | continue; | |
451 | } | |
452 | } | |
453 | normal: | |
1da177e4 LT |
454 | /* We might have grown an association since last we |
455 | * looked, so try again. | |
456 | * | |
457 | * This happens when we've just processed our | |
458 | * COOKIE-ECHO chunk. | |
459 | */ | |
460 | if (NULL == chunk->asoc) { | |
461 | asoc = sctp_endpoint_lookup_assoc(ep, | |
462 | sctp_source(chunk), | |
463 | &transport); | |
464 | chunk->asoc = asoc; | |
465 | chunk->transport = transport; | |
466 | } | |
467 | ||
468 | state = asoc ? asoc->state : SCTP_STATE_CLOSED; | |
bbd0d598 VY |
469 | if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth) |
470 | continue; | |
1da177e4 LT |
471 | |
472 | /* Remember where the last DATA chunk came from so we | |
473 | * know where to send the SACK. | |
474 | */ | |
475 | if (asoc && sctp_chunk_is_data(chunk)) | |
476 | asoc->peer.last_data_from = chunk->transport; | |
196d6759 | 477 | else { |
b01a2407 | 478 | SCTP_INC_STATS(sock_net(ep->base.sk), SCTP_MIB_INCTRLCHUNKS); |
196d6759 MB |
479 | if (asoc) |
480 | asoc->stats.ictrlchunks++; | |
481 | } | |
1da177e4 LT |
482 | |
483 | if (chunk->transport) | |
e575235f | 484 | chunk->transport->last_time_heard = ktime_get(); |
1da177e4 | 485 | |
55e26eb9 | 486 | error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, state, |
d808ad9a | 487 | ep, asoc, chunk, GFP_ATOMIC); |
1da177e4 LT |
488 | |
489 | if (error && chunk) | |
490 | chunk->pdiscard = 1; | |
491 | ||
492 | /* Check to see if the endpoint is freed in response to | |
493 | * the incoming chunk. If so, get out of the while loop. | |
494 | */ | |
495 | if (!sctp_sk(sk)->ep) | |
496 | break; | |
bbd0d598 VY |
497 | |
498 | if (first_time) | |
499 | first_time = 0; | |
1da177e4 LT |
500 | } |
501 | } |