#include "xalloc.h"
/* lists type of subnet */
-
+uint32_t hash_seed;
splay_tree_t subnet_tree = {
.compare = (splay_compare_t) subnet_compare,
.delete = (splay_action_t) free_subnet,
/* Subnet lookup cache */
-static hash_t *ipv4_cache;
-static hash_t *ipv6_cache;
-static hash_t *mac_cache;
+static uint32_t hash_function_ipv4_t(const ipv4_t *p) {
+ /*
+ This basic hash works because
+ a) Most IPv4 networks routed via tinc are not /0
+ b) Most IPv4 networks have more unique low order bits
+ */
+ uint16_t *halfwidth = (uint16_t *)p;
+ uint32_t hash = hash_seed;
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+ // 10.0.x.x/16 part
+ hash += halfwidth[1] * 0x9e370001UL;
+
+ // x.x.0.[0-255] part
+#if SUBNET_HASH_SIZE >= 0x10000
+ return hash ^ halfwidth[0];
+#else
+ // ensure that we have a /24 with no collisions on 32bit
+ return hash ^ ntohs(halfwidth[0]);
+#endif // _____LP64_____
+#else
+ // 10.0.x.x/16 part
+ hash += halfwidth[0] * 0x9e370001UL;
+
+ // x.x.0.[0-255] part (ntohs is nop on big endian)
+ return hash ^ halfwidth[1];
+#endif // __BYTE_ORDER == __LITTLE_ENDIAN
+}
+
+
+static uint32_t hash_function_ipv6_t(const ipv6_t *p) {
+ uint32_t *fullwidth = (uint32_t *)p;
+ uint32_t hash = hash_seed;
+
+ for(int i = 0; i < 4; i++) {
+ hash += fullwidth[i];
+ hash *= 0x9e370001UL;
+ }
+
+ return hash;
+}
+
+static uint32_t hash_function_mac_t(const mac_t *p) {
+ uint16_t *halfwidth = (uint16_t *)p;
+ uint32_t hash = hash_seed;
+
+ for(int i = 0; i < 3; i++) {
+ hash += halfwidth[i];
+ hash *= 0x9e370001UL;
+ }
+
+ return hash;
+}
+
+hash_define(ipv4_t, SUBNET_HASH_SIZE)
+hash_define(ipv6_t, SUBNET_HASH_SIZE)
+hash_define(mac_t, SUBNET_HASH_SIZE)
+
+hash_new(ipv4_t, ipv4_cache);
+hash_new(ipv6_t, ipv6_cache);
+hash_new(mac_t, mac_cache);
+
+
+void subnet_cache_flush_table(subnet_type_t stype) {
+ // NOTE: a subnet type of SUBNET_TYPES can be used to clear all hash tables
-void subnet_cache_flush(void) {
- hash_clear(ipv4_cache);
- hash_clear(ipv6_cache);
- hash_clear(mac_cache);
+ if(stype != SUBNET_IPV6) { // ipv4
+ hash_clear(ipv4_t, &ipv4_cache);
+ }
+
+ if(stype != SUBNET_IPV4) { // ipv6
+ hash_clear(ipv6_t, &ipv6_cache);
+ }
+
+ hash_clear(mac_t, &mac_cache);
}
/* Initialising trees */
void init_subnets(void) {
- ipv4_cache = hash_alloc(0x100, sizeof(ipv4_t));
- ipv6_cache = hash_alloc(0x100, sizeof(ipv6_t));
- mac_cache = hash_alloc(0x100, sizeof(mac_t));
+ hash_seed = (uint32_t)rand();
}
void exit_subnets(void) {
splay_empty_tree(&subnet_tree);
-
- hash_free(ipv4_cache);
- hash_free(ipv6_cache);
- hash_free(mac_cache);
+ subnet_cache_flush_tables();
}
void init_subnet_tree(splay_tree_t *tree) {
free(subnet);
}
+void subnet_cache_flush_tables(void) {
+ // flushes all the tables
+ hash_clear(ipv4_t, &ipv4_cache);
+ hash_clear(ipv6_t, &ipv6_cache);
+ hash_clear(mac_t, &mac_cache);
+}
+
+void subnet_cache_flush(subnet_t *subnet) {
+ switch(subnet->type) {
+ case SUBNET_IPV4:
+ if(subnet->net.ipv4.prefixlength == 32) {
+ hash_delete(ipv4_t, &ipv4_cache, &subnet->net.ipv4.address);
+ return;
+ }
+
+ break;
+
+ case SUBNET_IPV6:
+ if(subnet->net.ipv4.prefixlength == 128) {
+ hash_delete(ipv6_t, &ipv6_cache, &subnet->net.ipv6.address);
+ return;
+ }
+
+ break;
+
+ case SUBNET_MAC:
+ hash_delete(mac_t, &mac_cache, &subnet->net.mac.address);
+ return;
+ }
+
+ subnet_cache_flush_table(subnet->type);
+}
+
/* Adding and removing subnets */
void subnet_add(node_t *n, subnet_t *subnet) {
splay_insert(&n->subnet_tree, subnet);
}
- subnet_cache_flush();
+ subnet_cache_flush(subnet);
}
void subnet_del(node_t *n, subnet_t *subnet) {
splay_delete(&subnet_tree, subnet);
- subnet_cache_flush();
+ subnet_cache_flush(subnet);
}
/* Subnet lookup routines */
// Check if this address is cached
- if((r = hash_search(mac_cache, address))) {
+ if((r = hash_search(mac_t, &mac_cache, address))) {
return r;
}
// Cache the result
if(r) {
- hash_insert(mac_cache, address, r);
+ hash_insert(mac_t, &mac_cache, address, r);
}
return r;
// Check if this address is cached
- if((r = hash_search(ipv4_cache, address))) {
+ if((r = hash_search(ipv4_t, &ipv4_cache, address))) {
return r;
}
// Cache the result
if(r) {
- hash_insert(ipv4_cache, address, r);
+ hash_insert(ipv4_t, &ipv4_cache, address, r);
}
return r;
// Check if this address is cached
- if((r = hash_search(ipv6_cache, address))) {
+ if((r = hash_search(ipv6_t, &ipv6_cache, address))) {
return r;
}
// Cache the result
if(r) {
- hash_insert(ipv6_cache, address, r);
+ hash_insert(ipv6_t, &ipv6_cache, address, r);
}
return r;
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