1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
25 */
26
27 #include <sys/types.h>
28 #include <sys/stream.h>
29 #include <sys/strsun.h>
30 #include <sys/zone.h>
31 #include <sys/ddi.h>
32 #include <sys/disp.h>
33 #include <sys/sunddi.h>
34 #include <sys/cmn_err.h>
35 #include <sys/debug.h>
36 #include <sys/atomic.h>
37 #include <sys/callb.h>
38 #define _SUN_TPI_VERSION 2
39 #include <sys/tihdr.h>
40
41 #include <inet/common.h>
42 #include <inet/mi.h>
43 #include <inet/mib2.h>
44 #include <inet/snmpcom.h>
45
46 #include <netinet/ip6.h>
47 #include <netinet/icmp6.h>
48
49 #include <inet/ip.h>
50 #include <inet/ip_impl.h>
51 #include <inet/ip6.h>
52 #include <inet/ip6_asp.h>
53 #include <inet/ip_multi.h>
54 #include <inet/ip_if.h>
55 #include <inet/ip_ire.h>
56 #include <inet/ip_ftable.h>
57 #include <inet/ip_rts.h>
58 #include <inet/ip_ndp.h>
59 #include <inet/ipclassifier.h>
60 #include <inet/ip_listutils.h>
61
62 #include <sys/sunddi.h>
63
64 /*
65 * Routines for handling destination cache entries.
66 * There is always one DCEF_DEFAULT for each ip_stack_t created at init time.
67 * That entry holds both the IP ident value and the dce generation number.
68 *
69 * Any time a DCE is changed significantly (different path MTU, but NOT
70 * different ULP info!), the dce_generation number is increased.
71 * Also, when a new DCE is created, the dce_generation number in the default
72 * DCE is bumped. That allows the dce_t information to be cached efficiently
73 * as long as the entity caching the dce_t also caches the dce_generation,
74 * and compares the cached generation to detect any changes.
75 * Furthermore, when a DCE is deleted, if there are any outstanding references
76 * to the DCE it will be marked as condemned. The condemned mark is
77 * a designated generation number which is never otherwise used, hence
78 * the single comparison with the generation number captures that as well.
79 *
80 * An example of code which caches is as follows:
81 *
82 * if (mystruct->my_dce_generation != mystruct->my_dce->dce_generation) {
83 * The DCE has changed
84 * mystruct->my_dce = dce_lookup_pkt(mp, ixa,
85 * &mystruct->my_dce_generation);
86 * Not needed in practice, since we have the default DCE:
87 * if (DCE_IS_CONDEMNED(mystruct->my_dce))
88 * return failure;
89 * }
90 *
91 * Note that for IPv6 link-local addresses we record the ifindex since the
92 * link-locals are not globally unique.
93 */
94
95 /*
96 * Hash bucket structure for DCEs
97 */
98 typedef struct dcb_s {
99 krwlock_t dcb_lock;
100 uint32_t dcb_cnt;
101 dce_t *dcb_dce;
102 } dcb_t;
103
104 static void dce_delete_locked(dcb_t *, dce_t *);
105 static void dce_make_condemned(dce_t *);
106
107 static kmem_cache_t *dce_cache;
108 static kthread_t *dce_reclaim_thread;
109 static kmutex_t dce_reclaim_lock;
110 static kcondvar_t dce_reclaim_cv;
111 static int dce_reclaim_shutdown;
112
113 /* Global so it can be tuned in /etc/system. This must be a power of two. */
114 uint_t ip_dce_hash_size = 1024;
115
116 /* The time in seconds between executions of the IP DCE reclaim worker. */
117 uint_t ip_dce_reclaim_interval = 60;
118
119 /* The factor of the DCE threshold at which to start hard reclaims */
120 uint_t ip_dce_reclaim_threshold_hard = 2;
121
122 /* Operates on a uint64_t */
123 #define RANDOM_HASH(p) ((p) ^ ((p)>>16) ^ ((p)>>32) ^ ((p)>>48))
124
125 /*
126 * Reclaim a fraction of dce's in the dcb.
127 * For now we have a higher probability to delete DCEs without DCE_PMTU.
128 */
129 static void
dcb_reclaim(dcb_t * dcb,ip_stack_t * ipst,uint_t fraction)130 dcb_reclaim(dcb_t *dcb, ip_stack_t *ipst, uint_t fraction)
131 {
132 uint_t fraction_pmtu = fraction*4;
133 uint_t hash;
134 dce_t *dce, *nextdce;
135 hrtime_t seed = gethrtime();
136 uint_t retained = 0;
137 uint_t max = ipst->ips_ip_dce_reclaim_threshold;
138
139 max *= ip_dce_reclaim_threshold_hard;
140
141 rw_enter(&dcb->dcb_lock, RW_WRITER);
142 for (dce = dcb->dcb_dce; dce != NULL; dce = nextdce) {
143 nextdce = dce->dce_next;
144 /* Clear DCEF_PMTU if the pmtu is too old */
145 mutex_enter(&dce->dce_lock);
146 if ((dce->dce_flags & DCEF_PMTU) &&
147 TICK_TO_SEC(ddi_get_lbolt64()) - dce->dce_last_change_time >
148 ipst->ips_ip_pathmtu_interval) {
149 dce->dce_flags &= ~DCEF_PMTU;
150 mutex_exit(&dce->dce_lock);
151 dce_increment_generation(dce);
152 } else {
153 mutex_exit(&dce->dce_lock);
154 }
155
156 if (max == 0 || retained < max) {
157 hash = RANDOM_HASH((uint64_t)((uintptr_t)dce | seed));
158
159 if (dce->dce_flags & DCEF_PMTU) {
160 if (hash % fraction_pmtu != 0) {
161 retained++;
162 continue;
163 }
164 } else {
165 if (hash % fraction != 0) {
166 retained++;
167 continue;
168 }
169 }
170 }
171
172 IP_STAT(ipst, ip_dce_reclaim_deleted);
173 dce_delete_locked(dcb, dce);
174 dce_refrele(dce);
175 }
176 rw_exit(&dcb->dcb_lock);
177 }
178
179 /*
180 * kmem_cache callback to free up memory.
181 *
182 */
183 static void
ip_dce_reclaim_stack(ip_stack_t * ipst)184 ip_dce_reclaim_stack(ip_stack_t *ipst)
185 {
186 int i;
187
188 IP_STAT(ipst, ip_dce_reclaim_calls);
189 for (i = 0; i < ipst->ips_dce_hashsize; i++) {
190 dcb_reclaim(&ipst->ips_dce_hash_v4[i], ipst,
191 ipst->ips_ip_dce_reclaim_fraction);
192
193 dcb_reclaim(&ipst->ips_dce_hash_v6[i], ipst,
194 ipst->ips_ip_dce_reclaim_fraction);
195 }
196
197 /*
198 * Walk all CONNs that can have a reference on an ire, nce or dce.
199 * Get them to update any stale references to drop any refholds they
200 * have.
201 */
202 ipcl_walk(conn_ixa_cleanup, (void *)B_FALSE, ipst);
203 }
204
205 /*
206 * Called by dce_reclaim_worker() below, and no one else. Typically this will
207 * mean that the number of entries in the hash buckets has exceeded a tunable
208 * threshold.
209 */
210 static void
ip_dce_reclaim(void)211 ip_dce_reclaim(void)
212 {
213 netstack_handle_t nh;
214 netstack_t *ns;
215 ip_stack_t *ipst;
216
217 ASSERT(curthread == dce_reclaim_thread);
218
219 netstack_next_init(&nh);
220 while ((ns = netstack_next(&nh)) != NULL) {
221 /*
222 * netstack_next() can return a netstack_t with a NULL
223 * netstack_ip at boot time.
224 */
225 if ((ipst = ns->netstack_ip) == NULL) {
226 netstack_rele(ns);
227 continue;
228 }
229 if (atomic_swap_uint(&ipst->ips_dce_reclaim_needed, 0) != 0)
230 ip_dce_reclaim_stack(ipst);
231 netstack_rele(ns);
232 }
233 netstack_next_fini(&nh);
234 }
235
236 /* ARGSUSED */
237 static void
dce_reclaim_worker(void * arg)238 dce_reclaim_worker(void *arg)
239 {
240 callb_cpr_t cprinfo;
241
242 CALLB_CPR_INIT(&cprinfo, &dce_reclaim_lock, callb_generic_cpr,
243 "dce_reclaim_worker");
244
245 mutex_enter(&dce_reclaim_lock);
246 while (!dce_reclaim_shutdown) {
247 CALLB_CPR_SAFE_BEGIN(&cprinfo);
248 (void) cv_timedwait(&dce_reclaim_cv, &dce_reclaim_lock,
249 ddi_get_lbolt() + ip_dce_reclaim_interval * hz);
250 CALLB_CPR_SAFE_END(&cprinfo, &dce_reclaim_lock);
251
252 if (dce_reclaim_shutdown)
253 break;
254
255 mutex_exit(&dce_reclaim_lock);
256 ip_dce_reclaim();
257 mutex_enter(&dce_reclaim_lock);
258 }
259
260 ASSERT(MUTEX_HELD(&dce_reclaim_lock));
261 dce_reclaim_thread = NULL;
262 dce_reclaim_shutdown = 0;
263 cv_broadcast(&dce_reclaim_cv);
264 CALLB_CPR_EXIT(&cprinfo); /* drops the lock */
265
266 thread_exit();
267 }
268
269 void
dce_g_init(void)270 dce_g_init(void)
271 {
272 dce_cache = kmem_cache_create("dce_cache",
273 sizeof (dce_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
274
275 mutex_init(&dce_reclaim_lock, NULL, MUTEX_DEFAULT, NULL);
276 cv_init(&dce_reclaim_cv, NULL, CV_DEFAULT, NULL);
277
278 dce_reclaim_thread = thread_create(NULL, 0, dce_reclaim_worker,
279 NULL, 0, &p0, TS_RUN, minclsyspri);
280 }
281
282 void
dce_g_destroy(void)283 dce_g_destroy(void)
284 {
285 mutex_enter(&dce_reclaim_lock);
286 dce_reclaim_shutdown = 1;
287 cv_signal(&dce_reclaim_cv);
288 while (dce_reclaim_thread != NULL)
289 cv_wait(&dce_reclaim_cv, &dce_reclaim_lock);
290 mutex_exit(&dce_reclaim_lock);
291
292 cv_destroy(&dce_reclaim_cv);
293 mutex_destroy(&dce_reclaim_lock);
294
295 kmem_cache_destroy(dce_cache);
296 }
297
298 /*
299 * Allocate a default DCE and a hash table for per-IP address DCEs
300 */
301 void
dce_stack_init(ip_stack_t * ipst)302 dce_stack_init(ip_stack_t *ipst)
303 {
304 int i;
305
306 ipst->ips_dce_default = kmem_cache_alloc(dce_cache, KM_SLEEP);
307 bzero(ipst->ips_dce_default, sizeof (dce_t));
308 ipst->ips_dce_default->dce_flags = DCEF_DEFAULT;
309 ipst->ips_dce_default->dce_generation = DCE_GENERATION_INITIAL;
310 ipst->ips_dce_default->dce_last_change_time =
311 TICK_TO_SEC(ddi_get_lbolt64());
312 ipst->ips_dce_default->dce_refcnt = 1; /* Should never go away */
313 ipst->ips_dce_default->dce_ipst = ipst;
314
315 /* This must be a power of two since we are using IRE_ADDR_HASH macro */
316 ipst->ips_dce_hashsize = ip_dce_hash_size;
317 ipst->ips_dce_hash_v4 = kmem_zalloc(ipst->ips_dce_hashsize *
318 sizeof (dcb_t), KM_SLEEP);
319 ipst->ips_dce_hash_v6 = kmem_zalloc(ipst->ips_dce_hashsize *
320 sizeof (dcb_t), KM_SLEEP);
321 for (i = 0; i < ipst->ips_dce_hashsize; i++) {
322 rw_init(&ipst->ips_dce_hash_v4[i].dcb_lock, NULL, RW_DEFAULT,
323 NULL);
324 rw_init(&ipst->ips_dce_hash_v6[i].dcb_lock, NULL, RW_DEFAULT,
325 NULL);
326 }
327 }
328
329 void
dce_stack_destroy(ip_stack_t * ipst)330 dce_stack_destroy(ip_stack_t *ipst)
331 {
332 int i;
333 for (i = 0; i < ipst->ips_dce_hashsize; i++) {
334 rw_destroy(&ipst->ips_dce_hash_v4[i].dcb_lock);
335 rw_destroy(&ipst->ips_dce_hash_v6[i].dcb_lock);
336 }
337 kmem_free(ipst->ips_dce_hash_v4,
338 ipst->ips_dce_hashsize * sizeof (dcb_t));
339 ipst->ips_dce_hash_v4 = NULL;
340 kmem_free(ipst->ips_dce_hash_v6,
341 ipst->ips_dce_hashsize * sizeof (dcb_t));
342 ipst->ips_dce_hash_v6 = NULL;
343 ipst->ips_dce_hashsize = 0;
344
345 ASSERT(ipst->ips_dce_default->dce_refcnt == 1);
346 kmem_cache_free(dce_cache, ipst->ips_dce_default);
347 ipst->ips_dce_default = NULL;
348 }
349
350 /* When any DCE is good enough */
351 dce_t *
dce_get_default(ip_stack_t * ipst)352 dce_get_default(ip_stack_t *ipst)
353 {
354 dce_t *dce;
355
356 dce = ipst->ips_dce_default;
357 dce_refhold(dce);
358 return (dce);
359 }
360
361 /*
362 * Generic for IPv4 and IPv6.
363 *
364 * Used by callers that need to cache e.g., the datapath
365 * Returns the generation number in the last argument.
366 */
367 dce_t *
dce_lookup_pkt(mblk_t * mp,ip_xmit_attr_t * ixa,uint_t * generationp)368 dce_lookup_pkt(mblk_t *mp, ip_xmit_attr_t *ixa, uint_t *generationp)
369 {
370 if (ixa->ixa_flags & IXAF_IS_IPV4) {
371 /*
372 * If we have a source route we need to look for the final
373 * destination in the source route option.
374 */
375 ipaddr_t final_dst;
376 ipha_t *ipha = (ipha_t *)mp->b_rptr;
377
378 final_dst = ip_get_dst(ipha);
379 return (dce_lookup_v4(final_dst, ixa->ixa_ipst, generationp));
380 } else {
381 uint_t ifindex;
382 /*
383 * If we have a routing header we need to look for the final
384 * destination in the routing extension header.
385 */
386 in6_addr_t final_dst;
387 ip6_t *ip6h = (ip6_t *)mp->b_rptr;
388
389 final_dst = ip_get_dst_v6(ip6h, mp, NULL);
390 ifindex = 0;
391 if (IN6_IS_ADDR_LINKSCOPE(&final_dst) && ixa->ixa_nce != NULL) {
392 ifindex = ixa->ixa_nce->nce_common->ncec_ill->
393 ill_phyint->phyint_ifindex;
394 }
395 return (dce_lookup_v6(&final_dst, ifindex, ixa->ixa_ipst,
396 generationp));
397 }
398 }
399
400 /*
401 * Used by callers that need to cache e.g., the datapath
402 * Returns the generation number in the last argument.
403 */
404 dce_t *
dce_lookup_v4(ipaddr_t dst,ip_stack_t * ipst,uint_t * generationp)405 dce_lookup_v4(ipaddr_t dst, ip_stack_t *ipst, uint_t *generationp)
406 {
407 uint_t hash;
408 dcb_t *dcb;
409 dce_t *dce;
410
411 /* Set *generationp before dropping the lock(s) that allow additions */
412 if (generationp != NULL)
413 *generationp = ipst->ips_dce_default->dce_generation;
414
415 hash = IRE_ADDR_HASH(dst, ipst->ips_dce_hashsize);
416 dcb = &ipst->ips_dce_hash_v4[hash];
417 rw_enter(&dcb->dcb_lock, RW_READER);
418 for (dce = dcb->dcb_dce; dce != NULL; dce = dce->dce_next) {
419 if (dce->dce_v4addr == dst) {
420 mutex_enter(&dce->dce_lock);
421 if (!DCE_IS_CONDEMNED(dce)) {
422 dce_refhold(dce);
423 if (generationp != NULL)
424 *generationp = dce->dce_generation;
425 mutex_exit(&dce->dce_lock);
426 rw_exit(&dcb->dcb_lock);
427 return (dce);
428 }
429 mutex_exit(&dce->dce_lock);
430 }
431 }
432 rw_exit(&dcb->dcb_lock);
433 /* Not found */
434 dce = ipst->ips_dce_default;
435 dce_refhold(dce);
436 return (dce);
437 }
438
439 /*
440 * Used by callers that need to cache e.g., the datapath
441 * Returns the generation number in the last argument.
442 * ifindex should only be set for link-locals
443 */
444 dce_t *
dce_lookup_v6(const in6_addr_t * dst,uint_t ifindex,ip_stack_t * ipst,uint_t * generationp)445 dce_lookup_v6(const in6_addr_t *dst, uint_t ifindex, ip_stack_t *ipst,
446 uint_t *generationp)
447 {
448 uint_t hash;
449 dcb_t *dcb;
450 dce_t *dce;
451
452 /* Set *generationp before dropping the lock(s) that allow additions */
453 if (generationp != NULL)
454 *generationp = ipst->ips_dce_default->dce_generation;
455
456 hash = IRE_ADDR_HASH_V6(*dst, ipst->ips_dce_hashsize);
457 dcb = &ipst->ips_dce_hash_v6[hash];
458 rw_enter(&dcb->dcb_lock, RW_READER);
459 for (dce = dcb->dcb_dce; dce != NULL; dce = dce->dce_next) {
460 if (IN6_ARE_ADDR_EQUAL(&dce->dce_v6addr, dst) &&
461 dce->dce_ifindex == ifindex) {
462 mutex_enter(&dce->dce_lock);
463 if (!DCE_IS_CONDEMNED(dce)) {
464 dce_refhold(dce);
465 if (generationp != NULL)
466 *generationp = dce->dce_generation;
467 mutex_exit(&dce->dce_lock);
468 rw_exit(&dcb->dcb_lock);
469 return (dce);
470 }
471 mutex_exit(&dce->dce_lock);
472 }
473 }
474 rw_exit(&dcb->dcb_lock);
475 /* Not found */
476 dce = ipst->ips_dce_default;
477 dce_refhold(dce);
478 return (dce);
479 }
480
481 /*
482 * Atomically looks for a non-default DCE, and if not found tries to create one.
483 * If there is no memory it returns NULL.
484 * When an entry is created we increase the generation number on
485 * the default DCE so that conn_ip_output will detect there is a new DCE.
486 */
487 dce_t *
dce_lookup_and_add_v4(ipaddr_t dst,ip_stack_t * ipst)488 dce_lookup_and_add_v4(ipaddr_t dst, ip_stack_t *ipst)
489 {
490 uint_t hash;
491 dcb_t *dcb;
492 dce_t *dce;
493
494 hash = IRE_ADDR_HASH(dst, ipst->ips_dce_hashsize);
495 dcb = &ipst->ips_dce_hash_v4[hash];
496 /*
497 * Assuming that we get fairly even distribution across all of the
498 * buckets, once one bucket is overly full, prune the whole cache.
499 */
500 if (dcb->dcb_cnt > ipst->ips_ip_dce_reclaim_threshold)
501 atomic_or_uint(&ipst->ips_dce_reclaim_needed, 1);
502 rw_enter(&dcb->dcb_lock, RW_WRITER);
503 for (dce = dcb->dcb_dce; dce != NULL; dce = dce->dce_next) {
504 if (dce->dce_v4addr == dst) {
505 mutex_enter(&dce->dce_lock);
506 if (!DCE_IS_CONDEMNED(dce)) {
507 dce_refhold(dce);
508 mutex_exit(&dce->dce_lock);
509 rw_exit(&dcb->dcb_lock);
510 return (dce);
511 }
512 mutex_exit(&dce->dce_lock);
513 }
514 }
515 dce = kmem_cache_alloc(dce_cache, KM_NOSLEEP);
516 if (dce == NULL) {
517 rw_exit(&dcb->dcb_lock);
518 return (NULL);
519 }
520 bzero(dce, sizeof (dce_t));
521 dce->dce_ipst = ipst; /* No netstack_hold */
522 dce->dce_v4addr = dst;
523 dce->dce_generation = DCE_GENERATION_INITIAL;
524 dce->dce_ipversion = IPV4_VERSION;
525 dce->dce_last_change_time = TICK_TO_SEC(ddi_get_lbolt64());
526 dce_refhold(dce); /* For the hash list */
527
528 /* Link into list */
529 if (dcb->dcb_dce != NULL)
530 dcb->dcb_dce->dce_ptpn = &dce->dce_next;
531 dce->dce_next = dcb->dcb_dce;
532 dce->dce_ptpn = &dcb->dcb_dce;
533 dcb->dcb_dce = dce;
534 dce->dce_bucket = dcb;
535 atomic_inc_32(&dcb->dcb_cnt);
536 dce_refhold(dce); /* For the caller */
537 rw_exit(&dcb->dcb_lock);
538
539 /* Initialize dce_ident to be different than for the last packet */
540 dce->dce_ident = ipst->ips_dce_default->dce_ident + 1;
541
542 dce_increment_generation(ipst->ips_dce_default);
543 return (dce);
544 }
545
546 /*
547 * Atomically looks for a non-default DCE, and if not found tries to create one.
548 * If there is no memory it returns NULL.
549 * When an entry is created we increase the generation number on
550 * the default DCE so that conn_ip_output will detect there is a new DCE.
551 * ifindex should only be used with link-local addresses.
552 */
553 dce_t *
dce_lookup_and_add_v6(const in6_addr_t * dst,uint_t ifindex,ip_stack_t * ipst)554 dce_lookup_and_add_v6(const in6_addr_t *dst, uint_t ifindex, ip_stack_t *ipst)
555 {
556 uint_t hash;
557 dcb_t *dcb;
558 dce_t *dce;
559
560 /* We should not create entries for link-locals w/o an ifindex */
561 ASSERT(!(IN6_IS_ADDR_LINKSCOPE(dst)) || ifindex != 0);
562
563 hash = IRE_ADDR_HASH_V6(*dst, ipst->ips_dce_hashsize);
564 dcb = &ipst->ips_dce_hash_v6[hash];
565 /*
566 * Assuming that we get fairly even distribution across all of the
567 * buckets, once one bucket is overly full, prune the whole cache.
568 */
569 if (dcb->dcb_cnt > ipst->ips_ip_dce_reclaim_threshold)
570 atomic_or_uint(&ipst->ips_dce_reclaim_needed, 1);
571 rw_enter(&dcb->dcb_lock, RW_WRITER);
572 for (dce = dcb->dcb_dce; dce != NULL; dce = dce->dce_next) {
573 if (IN6_ARE_ADDR_EQUAL(&dce->dce_v6addr, dst) &&
574 dce->dce_ifindex == ifindex) {
575 mutex_enter(&dce->dce_lock);
576 if (!DCE_IS_CONDEMNED(dce)) {
577 dce_refhold(dce);
578 mutex_exit(&dce->dce_lock);
579 rw_exit(&dcb->dcb_lock);
580 return (dce);
581 }
582 mutex_exit(&dce->dce_lock);
583 }
584 }
585
586 dce = kmem_cache_alloc(dce_cache, KM_NOSLEEP);
587 if (dce == NULL) {
588 rw_exit(&dcb->dcb_lock);
589 return (NULL);
590 }
591 bzero(dce, sizeof (dce_t));
592 dce->dce_ipst = ipst; /* No netstack_hold */
593 dce->dce_v6addr = *dst;
594 dce->dce_ifindex = ifindex;
595 dce->dce_generation = DCE_GENERATION_INITIAL;
596 dce->dce_ipversion = IPV6_VERSION;
597 dce->dce_last_change_time = TICK_TO_SEC(ddi_get_lbolt64());
598 dce_refhold(dce); /* For the hash list */
599
600 /* Link into list */
601 if (dcb->dcb_dce != NULL)
602 dcb->dcb_dce->dce_ptpn = &dce->dce_next;
603 dce->dce_next = dcb->dcb_dce;
604 dce->dce_ptpn = &dcb->dcb_dce;
605 dcb->dcb_dce = dce;
606 dce->dce_bucket = dcb;
607 atomic_inc_32(&dcb->dcb_cnt);
608 dce_refhold(dce); /* For the caller */
609 rw_exit(&dcb->dcb_lock);
610
611 /* Initialize dce_ident to be different than for the last packet */
612 dce->dce_ident = ipst->ips_dce_default->dce_ident + 1;
613 dce_increment_generation(ipst->ips_dce_default);
614 return (dce);
615 }
616
617 /*
618 * Set/update uinfo. Creates a per-destination dce if none exists.
619 *
620 * Note that we do not bump the generation number here.
621 * New connections will find the new uinfo.
622 *
623 * The only use of this (tcp, sctp using iulp_t) is to set rtt+rtt_sd.
624 */
625 static void
dce_setuinfo(dce_t * dce,iulp_t * uinfo)626 dce_setuinfo(dce_t *dce, iulp_t *uinfo)
627 {
628 /*
629 * Update the round trip time estimate and/or the max frag size
630 * and/or the slow start threshold.
631 *
632 * We serialize multiple advises using dce_lock.
633 */
634 mutex_enter(&dce->dce_lock);
635 /* Gard against setting to zero */
636 if (uinfo->iulp_rtt != 0) {
637 /*
638 * If there is no old cached values, initialize them
639 * conservatively. Set them to be (1.5 * new value).
640 */
641 if (dce->dce_uinfo.iulp_rtt != 0) {
642 dce->dce_uinfo.iulp_rtt = (dce->dce_uinfo.iulp_rtt +
643 uinfo->iulp_rtt) >> 1;
644 } else {
645 dce->dce_uinfo.iulp_rtt = uinfo->iulp_rtt +
646 (uinfo->iulp_rtt >> 1);
647 }
648 if (dce->dce_uinfo.iulp_rtt_sd != 0) {
649 dce->dce_uinfo.iulp_rtt_sd =
650 (dce->dce_uinfo.iulp_rtt_sd +
651 uinfo->iulp_rtt_sd) >> 1;
652 } else {
653 dce->dce_uinfo.iulp_rtt_sd = uinfo->iulp_rtt_sd +
654 (uinfo->iulp_rtt_sd >> 1);
655 }
656 }
657 if (uinfo->iulp_mtu != 0) {
658 if (dce->dce_flags & DCEF_PMTU) {
659 dce->dce_pmtu = MIN(uinfo->iulp_mtu, dce->dce_pmtu);
660 } else {
661 dce->dce_pmtu = MIN(uinfo->iulp_mtu, IP_MAXPACKET);
662 dce->dce_flags |= DCEF_PMTU;
663 }
664 dce->dce_last_change_time = TICK_TO_SEC(ddi_get_lbolt64());
665 }
666 if (uinfo->iulp_ssthresh != 0) {
667 if (dce->dce_uinfo.iulp_ssthresh != 0)
668 dce->dce_uinfo.iulp_ssthresh =
669 (uinfo->iulp_ssthresh +
670 dce->dce_uinfo.iulp_ssthresh) >> 1;
671 else
672 dce->dce_uinfo.iulp_ssthresh = uinfo->iulp_ssthresh;
673 }
674 /* We have uinfo for sure */
675 dce->dce_flags |= DCEF_UINFO;
676 mutex_exit(&dce->dce_lock);
677 }
678
679
680 int
dce_update_uinfo_v4(ipaddr_t dst,iulp_t * uinfo,ip_stack_t * ipst)681 dce_update_uinfo_v4(ipaddr_t dst, iulp_t *uinfo, ip_stack_t *ipst)
682 {
683 dce_t *dce;
684
685 dce = dce_lookup_and_add_v4(dst, ipst);
686 if (dce == NULL)
687 return (ENOMEM);
688
689 dce_setuinfo(dce, uinfo);
690 dce_refrele(dce);
691 return (0);
692 }
693
694 int
dce_update_uinfo_v6(const in6_addr_t * dst,uint_t ifindex,iulp_t * uinfo,ip_stack_t * ipst)695 dce_update_uinfo_v6(const in6_addr_t *dst, uint_t ifindex, iulp_t *uinfo,
696 ip_stack_t *ipst)
697 {
698 dce_t *dce;
699
700 dce = dce_lookup_and_add_v6(dst, ifindex, ipst);
701 if (dce == NULL)
702 return (ENOMEM);
703
704 dce_setuinfo(dce, uinfo);
705 dce_refrele(dce);
706 return (0);
707 }
708
709 /* Common routine for IPv4 and IPv6 */
710 int
dce_update_uinfo(const in6_addr_t * dst,uint_t ifindex,iulp_t * uinfo,ip_stack_t * ipst)711 dce_update_uinfo(const in6_addr_t *dst, uint_t ifindex, iulp_t *uinfo,
712 ip_stack_t *ipst)
713 {
714 ipaddr_t dst4;
715
716 if (IN6_IS_ADDR_V4MAPPED_ANY(dst)) {
717 IN6_V4MAPPED_TO_IPADDR(dst, dst4);
718 return (dce_update_uinfo_v4(dst4, uinfo, ipst));
719 } else {
720 return (dce_update_uinfo_v6(dst, ifindex, uinfo, ipst));
721 }
722 }
723
724 static void
dce_make_condemned(dce_t * dce)725 dce_make_condemned(dce_t *dce)
726 {
727 ip_stack_t *ipst = dce->dce_ipst;
728
729 mutex_enter(&dce->dce_lock);
730 ASSERT(!DCE_IS_CONDEMNED(dce));
731 dce->dce_generation = DCE_GENERATION_CONDEMNED;
732 mutex_exit(&dce->dce_lock);
733 /* Count how many condemned dces for kmem_cache callback */
734 atomic_inc_32(&ipst->ips_num_dce_condemned);
735 }
736
737 /*
738 * Increment the generation avoiding the special condemned value
739 */
740 void
dce_increment_generation(dce_t * dce)741 dce_increment_generation(dce_t *dce)
742 {
743 uint_t generation;
744
745 mutex_enter(&dce->dce_lock);
746 if (!DCE_IS_CONDEMNED(dce)) {
747 generation = dce->dce_generation + 1;
748 if (generation == DCE_GENERATION_CONDEMNED)
749 generation = DCE_GENERATION_INITIAL;
750 ASSERT(generation != DCE_GENERATION_VERIFY);
751 dce->dce_generation = generation;
752 }
753 mutex_exit(&dce->dce_lock);
754 }
755
756 /*
757 * Increment the generation number on all dces that have a path MTU and
758 * the default DCE. Used when ill_mtu or ill_mc_mtu changes.
759 */
760 void
dce_increment_all_generations(boolean_t isv6,ip_stack_t * ipst)761 dce_increment_all_generations(boolean_t isv6, ip_stack_t *ipst)
762 {
763 int i;
764 dcb_t *dcb;
765 dce_t *dce;
766
767 for (i = 0; i < ipst->ips_dce_hashsize; i++) {
768 if (isv6)
769 dcb = &ipst->ips_dce_hash_v6[i];
770 else
771 dcb = &ipst->ips_dce_hash_v4[i];
772 rw_enter(&dcb->dcb_lock, RW_WRITER);
773 for (dce = dcb->dcb_dce; dce != NULL; dce = dce->dce_next) {
774 if (DCE_IS_CONDEMNED(dce))
775 continue;
776 dce_increment_generation(dce);
777 }
778 rw_exit(&dcb->dcb_lock);
779 }
780 dce_increment_generation(ipst->ips_dce_default);
781 }
782
783 /*
784 * Caller needs to do a dce_refrele since we can't do the
785 * dce_refrele under dcb_lock.
786 */
787 static void
dce_delete_locked(dcb_t * dcb,dce_t * dce)788 dce_delete_locked(dcb_t *dcb, dce_t *dce)
789 {
790 dce->dce_bucket = NULL;
791 *dce->dce_ptpn = dce->dce_next;
792 if (dce->dce_next != NULL)
793 dce->dce_next->dce_ptpn = dce->dce_ptpn;
794 dce->dce_ptpn = NULL;
795 dce->dce_next = NULL;
796 atomic_dec_32(&dcb->dcb_cnt);
797 dce_make_condemned(dce);
798 }
799
800 static void
dce_inactive(dce_t * dce)801 dce_inactive(dce_t *dce)
802 {
803 ip_stack_t *ipst = dce->dce_ipst;
804
805 ASSERT(!(dce->dce_flags & DCEF_DEFAULT));
806 ASSERT(dce->dce_ptpn == NULL);
807 ASSERT(dce->dce_bucket == NULL);
808
809 /* Count how many condemned dces for kmem_cache callback */
810 if (DCE_IS_CONDEMNED(dce))
811 atomic_dec_32(&ipst->ips_num_dce_condemned);
812
813 kmem_cache_free(dce_cache, dce);
814 }
815
816 void
dce_refrele(dce_t * dce)817 dce_refrele(dce_t *dce)
818 {
819 ASSERT(dce->dce_refcnt != 0);
820 if (atomic_dec_32_nv(&dce->dce_refcnt) == 0)
821 dce_inactive(dce);
822 }
823
824 void
dce_refhold(dce_t * dce)825 dce_refhold(dce_t *dce)
826 {
827 atomic_inc_32(&dce->dce_refcnt);
828 ASSERT(dce->dce_refcnt != 0);
829 }
830
831 /* No tracing support yet hence the same as the above functions */
832 void
dce_refrele_notr(dce_t * dce)833 dce_refrele_notr(dce_t *dce)
834 {
835 ASSERT(dce->dce_refcnt != 0);
836 if (atomic_dec_32_nv(&dce->dce_refcnt) == 0)
837 dce_inactive(dce);
838 }
839
840 void
dce_refhold_notr(dce_t * dce)841 dce_refhold_notr(dce_t *dce)
842 {
843 atomic_inc_32(&dce->dce_refcnt);
844 ASSERT(dce->dce_refcnt != 0);
845 }
846
847 /* Report both the IPv4 and IPv6 DCEs. */
848 mblk_t *
ip_snmp_get_mib2_ip_dce(queue_t * q,mblk_t * mpctl,ip_stack_t * ipst)849 ip_snmp_get_mib2_ip_dce(queue_t *q, mblk_t *mpctl, ip_stack_t *ipst)
850 {
851 struct opthdr *optp;
852 mblk_t *mp2ctl;
853 dest_cache_entry_t dest_cache;
854 mblk_t *mp_tail = NULL;
855 dce_t *dce;
856 dcb_t *dcb;
857 int i;
858 uint64_t current_time;
859
860 current_time = TICK_TO_SEC(ddi_get_lbolt64());
861
862 /*
863 * make a copy of the original message
864 */
865 mp2ctl = copymsg(mpctl);
866
867 /* First we do IPv4 entries */
868 optp = (struct opthdr *)&mpctl->b_rptr[
869 sizeof (struct T_optmgmt_ack)];
870 optp->level = MIB2_IP;
871 optp->name = EXPER_IP_DCE;
872
873 for (i = 0; i < ipst->ips_dce_hashsize; i++) {
874 dcb = &ipst->ips_dce_hash_v4[i];
875 rw_enter(&dcb->dcb_lock, RW_READER);
876 for (dce = dcb->dcb_dce; dce != NULL; dce = dce->dce_next) {
877 dest_cache.DestIpv4Address = dce->dce_v4addr;
878 dest_cache.DestFlags = dce->dce_flags;
879 if (dce->dce_flags & DCEF_PMTU)
880 dest_cache.DestPmtu = dce->dce_pmtu;
881 else
882 dest_cache.DestPmtu = 0;
883 dest_cache.DestIdent = dce->dce_ident;
884 dest_cache.DestIfindex = 0;
885 dest_cache.DestAge = current_time -
886 dce->dce_last_change_time;
887 if (!snmp_append_data2(mpctl->b_cont, &mp_tail,
888 (char *)&dest_cache, (int)sizeof (dest_cache))) {
889 ip1dbg(("ip_snmp_get_mib2_ip_dce: "
890 "failed to allocate %u bytes\n",
891 (uint_t)sizeof (dest_cache)));
892 }
893 }
894 rw_exit(&dcb->dcb_lock);
895 }
896 optp->len = (t_uscalar_t)msgdsize(mpctl->b_cont);
897 ip3dbg(("ip_snmp_get: level %d, name %d, len %d\n",
898 (int)optp->level, (int)optp->name, (int)optp->len));
899 qreply(q, mpctl);
900
901 if (mp2ctl == NULL) {
902 /* Copymsg failed above */
903 return (NULL);
904 }
905
906 /* Now for IPv6 */
907 mpctl = mp2ctl;
908 mp_tail = NULL;
909 mp2ctl = copymsg(mpctl);
910 optp = (struct opthdr *)&mpctl->b_rptr[
911 sizeof (struct T_optmgmt_ack)];
912 optp->level = MIB2_IP6;
913 optp->name = EXPER_IP_DCE;
914
915 for (i = 0; i < ipst->ips_dce_hashsize; i++) {
916 dcb = &ipst->ips_dce_hash_v6[i];
917 rw_enter(&dcb->dcb_lock, RW_READER);
918 for (dce = dcb->dcb_dce; dce != NULL; dce = dce->dce_next) {
919 dest_cache.DestIpv6Address = dce->dce_v6addr;
920 dest_cache.DestFlags = dce->dce_flags;
921 if (dce->dce_flags & DCEF_PMTU)
922 dest_cache.DestPmtu = dce->dce_pmtu;
923 else
924 dest_cache.DestPmtu = 0;
925 dest_cache.DestIdent = dce->dce_ident;
926 if (IN6_IS_ADDR_LINKSCOPE(&dce->dce_v6addr))
927 dest_cache.DestIfindex = dce->dce_ifindex;
928 else
929 dest_cache.DestIfindex = 0;
930 dest_cache.DestAge = current_time -
931 dce->dce_last_change_time;
932 if (!snmp_append_data2(mpctl->b_cont, &mp_tail,
933 (char *)&dest_cache, (int)sizeof (dest_cache))) {
934 ip1dbg(("ip_snmp_get_mib2_ip_dce: "
935 "failed to allocate %u bytes\n",
936 (uint_t)sizeof (dest_cache)));
937 }
938 }
939 rw_exit(&dcb->dcb_lock);
940 }
941 optp->len = (t_uscalar_t)msgdsize(mpctl->b_cont);
942 ip3dbg(("ip_snmp_get: level %d, name %d, len %d\n",
943 (int)optp->level, (int)optp->name, (int)optp->len));
944 qreply(q, mpctl);
945
946 return (mp2ctl);
947 }
948
949 /*
950 * Remove IPv6 DCEs which refer to an ifindex that is going away.
951 * This is not required for correctness, but it avoids netstat -d
952 * showing stale stuff that will never be used.
953 */
954 void
dce_cleanup(uint_t ifindex,ip_stack_t * ipst)955 dce_cleanup(uint_t ifindex, ip_stack_t *ipst)
956 {
957 uint_t i;
958 dcb_t *dcb;
959 dce_t *dce, *nextdce;
960
961 for (i = 0; i < ipst->ips_dce_hashsize; i++) {
962 dcb = &ipst->ips_dce_hash_v6[i];
963 rw_enter(&dcb->dcb_lock, RW_WRITER);
964
965 for (dce = dcb->dcb_dce; dce != NULL; dce = nextdce) {
966 nextdce = dce->dce_next;
967 if (dce->dce_ifindex == ifindex) {
968 dce_delete_locked(dcb, dce);
969 dce_refrele(dce);
970 }
971 }
972 rw_exit(&dcb->dcb_lock);
973 }
974 }
975