X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fsubnet.c;h=602177ffef3e146bccb71a49c42eba50112bb572;hb=ac2a1722b71e98010324ed46235e96bfa6e672f5;hp=4fefda6ff8f47996c380eabf2165da7d72b1aa9f;hpb=f6e87ab476a0faf8b124ecaaa27f967d825e6457;p=tinc

diff --git a/src/subnet.c b/src/subnet.c
index 4fefda6f..602177ff 100644
--- a/src/subnet.c
+++ b/src/subnet.c
@@ -22,58 +22,126 @@
 
 #include "splay_tree.h"
 #include "control_common.h"
-#include "device.h"
 #include "hash.h"
 #include "logger.h"
-#include "names.h"
 #include "net.h"
 #include "netutl.h"
 #include "node.h"
 #include "script.h"
 #include "subnet.h"
-#include "utils.h"
 #include "xalloc.h"
 
 /* lists type of subnet */
-
-splay_tree_t *subnet_tree;
+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 wrapping_add32(uint32_t a, uint32_t b) {
+	return (uint32_t)((uint64_t)a + b);
+}
 
-void subnet_cache_flush(void) {
-	hash_clear(ipv4_cache);
-	hash_clear(ipv6_cache);
-	hash_clear(mac_cache);
+static uint32_t wrapping_mul32(uint32_t a, uint32_t b) {
+	return (uint32_t)((uint64_t)a * b);
 }
 
-/* Initialising trees */
+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 = wrapping_add32(hash, wrapping_mul32(halfwidth[1], 0x9e370001U));
+
+	// 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 = wrapping_add32(hash, wrapping_mul32(halfwidth[0], 0x9e370001U));
+
+	// x.x.0.[0-255] part (ntohs is nop on big endian)
+	return hash ^ halfwidth[1];
+#endif // __BYTE_ORDER == __LITTLE_ENDIAN
+}
 
-void init_subnets(void) {
-	subnet_tree = splay_alloc_tree((splay_compare_t) subnet_compare, (splay_action_t) free_subnet);
 
-	ipv4_cache = hash_alloc(0x100, sizeof(ipv4_t));
-	ipv6_cache = hash_alloc(0x100, sizeof(ipv6_t));
-	mac_cache = hash_alloc(0x100, sizeof(mac_t));
+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 = wrapping_mul32(hash, 0x9e370001U);
+	}
+
+	return hash;
 }
 
-void exit_subnets(void) {
-	splay_delete_tree(subnet_tree);
+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 = wrapping_mul32(hash, 0x9e370001U);
+	}
+
+	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
+
+	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 */
 
-	hash_free(ipv4_cache);
-	hash_free(ipv6_cache);
-	hash_free(mac_cache);
+void init_subnets(void) {
+	hash_seed = (uint32_t)rand();
+
+	// tables need to be cleared on startup
+	subnet_cache_flush_tables();
 }
 
-splay_tree_t *new_subnet_tree(void) {
-	return splay_alloc_tree((splay_compare_t) subnet_compare, NULL);
+void exit_subnets(void) {
+	splay_empty_tree(&subnet_tree);
+	subnet_cache_flush_tables();
 }
 
-void free_subnet_tree(splay_tree_t *subnet_tree) {
-	splay_delete_tree(subnet_tree);
+void init_subnet_tree(splay_tree_t *tree) {
+	memset(tree, 0, sizeof(*tree));
+	tree->compare = (splay_compare_t) subnet_compare;
 }
 
 /* Allocating and freeing space for subnets */
@@ -86,34 +154,67 @@ void free_subnet(subnet_t *subnet) {
 	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) {
 	subnet->owner = n;
 
-	splay_insert(subnet_tree, subnet);
+	splay_insert(&subnet_tree, subnet);
 
 	if(n) {
-		splay_insert(n->subnet_tree, subnet);
+		splay_insert(&n->subnet_tree, subnet);
 	}
 
-	subnet_cache_flush();
+	subnet_cache_flush(subnet);
 }
 
 void subnet_del(node_t *n, subnet_t *subnet) {
 	if(n) {
-		splay_delete(n->subnet_tree, subnet);
+		splay_delete(&n->subnet_tree, subnet);
 	}
 
-	splay_delete(subnet_tree, subnet);
+	splay_delete(&subnet_tree, subnet);
 
-	subnet_cache_flush();
+	subnet_cache_flush(subnet);
 }
 
 /* Subnet lookup routines */
 
-subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet) {
-	return splay_search(owner->subnet_tree, subnet);
+subnet_t *lookup_subnet(node_t *owner, const subnet_t *subnet) {
+	return splay_search(&owner->subnet_tree, subnet);
 }
 
 subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) {
@@ -121,13 +222,13 @@ subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) {
 
 	// Check if this address is cached
 
-	if((r = hash_search(mac_cache, address))) {
+	if((r = hash_search(mac_t, &mac_cache, address))) {
 		return r;
 	}
 
 	// Search all subnets for a matching one
 
-	for splay_each(subnet_t, p, owner ? owner->subnet_tree : subnet_tree) {
+	for splay_each(subnet_t, p, owner ? &owner->subnet_tree : &subnet_tree) {
 		if(!p || p->type != SUBNET_MAC) {
 			continue;
 		}
@@ -144,7 +245,7 @@ subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) {
 	// Cache the result
 
 	if(r) {
-		hash_insert(mac_cache, address, r);
+		hash_insert(mac_t, &mac_cache, address, r);
 	}
 
 	return r;
@@ -155,13 +256,13 @@ subnet_t *lookup_subnet_ipv4(const ipv4_t *address) {
 
 	// Check if this address is cached
 
-	if((r = hash_search(ipv4_cache, address))) {
+	if((r = hash_search(ipv4_t, &ipv4_cache, address))) {
 		return r;
 	}
 
 	// Search all subnets for a matching one
 
-	for splay_each(subnet_t, p, subnet_tree) {
+	for splay_each(subnet_t, p, &subnet_tree) {
 		if(!p || p->type != SUBNET_IPV4) {
 			continue;
 		}
@@ -178,7 +279,7 @@ subnet_t *lookup_subnet_ipv4(const ipv4_t *address) {
 	// Cache the result
 
 	if(r) {
-		hash_insert(ipv4_cache, address, r);
+		hash_insert(ipv4_t, &ipv4_cache, address, r);
 	}
 
 	return r;
@@ -189,13 +290,13 @@ subnet_t *lookup_subnet_ipv6(const ipv6_t *address) {
 
 	// Check if this address is cached
 
-	if((r = hash_search(ipv6_cache, address))) {
+	if((r = hash_search(ipv6_t, &ipv6_cache, address))) {
 		return r;
 	}
 
 	// Search all subnets for a matching one
 
-	for splay_each(subnet_t, p, subnet_tree) {
+	for splay_each(subnet_t, p, &subnet_tree) {
 		if(!p || p->type != SUBNET_IPV6) {
 			continue;
 		}
@@ -212,7 +313,7 @@ subnet_t *lookup_subnet_ipv6(const ipv6_t *address) {
 	// Cache the result
 
 	if(r) {
-		hash_insert(ipv6_cache, address, r);
+		hash_insert(ipv6_t, &ipv6_cache, address, r);
 	}
 
 	return r;
@@ -243,7 +344,7 @@ void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 	name = up ? "subnet-up" : "subnet-down";
 
 	if(!subnet) {
-		for splay_each(subnet_t, subnet, owner->subnet_tree) {
+		for splay_each(subnet_t, subnet, &owner->subnet_tree) {
 			if(!net2str(netstr, sizeof(netstr), subnet)) {
 				continue;
 			}
@@ -286,7 +387,7 @@ void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 }
 
 bool dump_subnets(connection_t *c) {
-	for splay_each(subnet_t, subnet, subnet_tree) {
+	for splay_each(subnet_t, subnet, &subnet_tree) {
 		char netstr[MAXNETSTR];
 
 		if(!net2str(netstr, sizeof(netstr), subnet)) {