X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fsubnet.c;h=1ddf11e53b7e1bb8ea678a1944273ce745a5efe2;hb=e62fd508158749a0d55eae06c2e361df5d6da6e0;hp=8c766378f1ee84a7ca7880a32ca1f74d648fe008;hpb=9a018c2e371eb1cef9708ac71653f2f2868895fa;p=tinc

diff --git a/src/subnet.c b/src/subnet.c
index 8c766378..1ddf11e5 100644
--- a/src/subnet.c
+++ b/src/subnet.c
@@ -1,6 +1,6 @@
 /*
     subnet.c -- handle subnet lookups and lists
-    Copyright (C) 2000-2017 Guus Sliepen <guus@tinc-vpn.org>,
+    Copyright (C) 2000-2022 Guus Sliepen <guus@tinc-vpn.org>,
                   2000-2005 Ivo Timmermans
 
     This program is free software; you can redistribute it and/or modify
@@ -22,6 +22,7 @@
 
 #include "splay_tree.h"
 #include "control_common.h"
+#include "crypto.h"
 #include "hash.h"
 #include "logger.h"
 #include "net.h"
@@ -40,6 +41,14 @@ splay_tree_t subnet_tree = {
 
 /* Subnet lookup cache */
 
+static uint32_t wrapping_add32(uint32_t a, uint32_t b) {
+	return (uint32_t)((uint64_t)a + b);
+}
+
+static uint32_t wrapping_mul32(uint32_t a, uint32_t b) {
+	return (uint32_t)((uint64_t)a * b);
+}
+
 static uint32_t hash_function_ipv4_t(const ipv4_t *p) {
 	/*
 	This basic hash works because
@@ -51,7 +60,7 @@ static uint32_t hash_function_ipv4_t(const ipv4_t *p) {
 
 #if __BYTE_ORDER == __LITTLE_ENDIAN
 	// 10.0.x.x/16 part
-	hash += halfwidth[1] * 0x9e370001UL;
+	hash = wrapping_add32(hash, wrapping_mul32(halfwidth[1], 0x9e370001U));
 
 	// x.x.0.[0-255] part
 #if SUBNET_HASH_SIZE >= 0x10000
@@ -62,7 +71,7 @@ static uint32_t hash_function_ipv4_t(const ipv4_t *p) {
 #endif // _____LP64_____
 #else
 	// 10.0.x.x/16 part
-	hash += halfwidth[0] * 0x9e370001UL;
+	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];
@@ -75,8 +84,8 @@ static uint32_t hash_function_ipv6_t(const ipv6_t *p) {
 	uint32_t hash = hash_seed;
 
 	for(int i = 0; i < 4; i++) {
-		hash += fullwidth[i];
-		hash *= 0x9e370001UL;
+		hash = wrapping_add32(hash, fullwidth[i]);
+		hash = wrapping_mul32(hash, 0x9e370001U);
 	}
 
 	return hash;
@@ -87,8 +96,8 @@ static uint32_t hash_function_mac_t(const mac_t *p) {
 	uint32_t hash = hash_seed;
 
 	for(int i = 0; i < 3; i++) {
-		hash += halfwidth[i];
-		hash *= 0x9e370001UL;
+		hash = wrapping_add32(hash, halfwidth[i]);
+		hash = wrapping_mul32(hash, 0x9e370001U);
 	}
 
 	return hash;
@@ -120,7 +129,10 @@ void subnet_cache_flush_table(subnet_type_t stype) {
 /* Initialising trees */
 
 void init_subnets(void) {
-	hash_seed = (uint32_t)rand();
+	hash_seed = prng(UINT32_MAX);
+
+	// tables need to be cleared on startup
+	subnet_cache_flush_tables();
 }
 
 void exit_subnets(void) {
@@ -150,7 +162,7 @@ void subnet_cache_flush_tables(void) {
 	hash_clear(mac_t, &mac_cache);
 }
 
-void subnet_cache_flush(subnet_t *subnet) {
+static void subnet_cache_flush(subnet_t *subnet) {
 	switch(subnet->type) {
 	case SUBNET_IPV4:
 		if(subnet->net.ipv4.prefixlength == 32) {
@@ -310,7 +322,7 @@ subnet_t *lookup_subnet_ipv6(const ipv6_t *address) {
 
 void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 	char netstr[MAXNETSTR];
-	char *name, *address, *port;
+	char *address, *port;
 	char empty[] = "";
 
 	// Prepare environment variables to be passed to the script
@@ -330,7 +342,7 @@ void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
 	int env_subnet = environment_add(&env, NULL);
 	int env_weight = environment_add(&env, NULL);
 
-	name = up ? "subnet-up" : "subnet-down";
+	const char *name = up ? "subnet-up" : "subnet-down";
 
 	if(!subnet) {
 		for splay_each(subnet_t, subnet, &owner->subnet_tree) {