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val_kcache.c revision 1.1.1.4 
      1 /*
      2  * validator/val_kcache.c - validator key shared cache with validated keys
      3  *
      4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
      5  *
      6  * This software is open source.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  *
     12  * Redistributions of source code must retain the above copyright notice,
     13  * this list of conditions and the following disclaimer.
     14  *
     15  * Redistributions in binary form must reproduce the above copyright notice,
     16  * this list of conditions and the following disclaimer in the documentation
     17  * and/or other materials provided with the distribution.
     18  *
     19  * Neither the name of the NLNET LABS nor the names of its contributors may
     20  * be used to endorse or promote products derived from this software without
     21  * specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
     29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     34  */
     35 
     36 /**
     37  * \file
     38  *
     39  * This file contains functions for dealing with the validator key cache.
     40  */
     41 #include "config.h"
     42 #include "validator/val_kcache.h"
     43 #include "validator/val_kentry.h"
     44 #include "util/log.h"
     45 #include "util/config_file.h"
     46 #include "util/data/dname.h"
     47 #include "util/module.h"
     48 
     49 struct key_cache*
     50 key_cache_create(struct config_file* cfg)
     51 {
     52 	struct key_cache* kcache = (struct key_cache*)calloc(1,
     53 		sizeof(*kcache));
     54 	size_t numtables, start_size, maxmem;
     55 	if(!kcache) {
     56 		log_err("malloc failure");
     57 		return NULL;
     58 	}
     59 	numtables = cfg->key_cache_slabs;
     60 	start_size = HASH_DEFAULT_STARTARRAY;
     61 	maxmem = cfg->key_cache_size;
     62 	kcache->slab = slabhash_create(numtables, start_size, maxmem,
     63 		&key_entry_sizefunc, &key_entry_compfunc,
     64 		&key_entry_delkeyfunc, &key_entry_deldatafunc, NULL);
     65 	if(!kcache->slab) {
     66 		log_err("malloc failure");
     67 		free(kcache);
     68 		return NULL;
     69 	}
     70 	return kcache;
     71 }
     72 
     73 void
     74 key_cache_delete(struct key_cache* kcache)
     75 {
     76 	if(!kcache)
     77 		return;
     78 	slabhash_delete(kcache->slab);
     79 	free(kcache);
     80 }
     81 
     82 void
     83 key_cache_insert(struct key_cache* kcache, struct key_entry_key* kkey,
     84 	int copy_reason)
     85 {
     86 	struct key_entry_key* k = key_entry_copy(kkey, copy_reason);
     87 	if(!k)
     88 		return;
     89 	key_entry_hash(k);
     90 	slabhash_insert(kcache->slab, k->entry.hash, &k->entry,
     91 		k->entry.data, NULL);
     92 }
     93 
     94 /**
     95  * Lookup exactly in the key cache. Returns pointer to locked entry.
     96  * Caller must unlock it after use.
     97  * @param kcache: the key cache.
     98  * @param name: for what name to look; uncompressed wireformat
     99  * @param namelen: length of the name.
    100  * @param key_class: class of the key.
    101  * @param wr: set true to get a writelock.
    102  * @return key entry, locked, or NULL if not found. No TTL checking is
    103  * 	performed.
    104  */
    105 static struct key_entry_key*
    106 key_cache_search(struct key_cache* kcache, uint8_t* name, size_t namelen,
    107 	uint16_t key_class, int wr)
    108 {
    109 	struct lruhash_entry* e;
    110 	struct key_entry_key lookfor;
    111 	lookfor.entry.key = &lookfor;
    112 	lookfor.name = name;
    113 	lookfor.namelen = namelen;
    114 	lookfor.key_class = key_class;
    115 	key_entry_hash(&lookfor);
    116 	e = slabhash_lookup(kcache->slab, lookfor.entry.hash, &lookfor, wr);
    117 	if(!e)
    118 		return NULL;
    119 	return (struct key_entry_key*)e->key;
    120 }
    121 
    122 struct key_entry_key*
    123 key_cache_obtain(struct key_cache* kcache, uint8_t* name, size_t namelen,
    124 	uint16_t key_class, struct regional* region, time_t now)
    125 {
    126 	/* keep looking until we find a nonexpired entry */
    127 	while(1) {
    128 		struct key_entry_key* k = key_cache_search(kcache, name,
    129 			namelen, key_class, 0);
    130 		if(k) {
    131 			/* see if TTL is OK */
    132 			struct key_entry_data* d = (struct key_entry_data*)
    133 				k->entry.data;
    134 			if(now <= d->ttl) {
    135 				/* copy and return it */
    136 				struct key_entry_key* retkey =
    137 					key_entry_copy_toregion(k, region);
    138 				lock_rw_unlock(&k->entry.lock);
    139 				return retkey;
    140 			}
    141 			lock_rw_unlock(&k->entry.lock);
    142 		}
    143 		/* snip off first label to continue */
    144 		if(dname_is_root(name))
    145 			break;
    146 		dname_remove_label(&name, &namelen);
    147 	}
    148 	return NULL;
    149 }
    150 
    151 size_t
    152 key_cache_get_mem(struct key_cache* kcache)
    153 {
    154 	return sizeof(*kcache) + slabhash_get_mem(kcache->slab);
    155 }
    156 
    157 void key_cache_remove(struct key_cache* kcache,
    158 	uint8_t* name, size_t namelen, uint16_t key_class)
    159 {
    160 	struct key_entry_key lookfor;
    161 	lookfor.entry.key = &lookfor;
    162 	lookfor.name = name;
    163 	lookfor.namelen = namelen;
    164 	lookfor.key_class = key_class;
    165 	key_entry_hash(&lookfor);
    166 	slabhash_remove(kcache->slab, lookfor.entry.hash, &lookfor);
    167 }
    168