+ unsigned int res;
+ /* Only use the first 64 bits of address, since the last 64 bits
+ * tend to be under user control. */
+ res = ip->in6_16[0] ^ ip->in6_16[1] ^ ip->in6_16[2] ^ ip->in6_16[3];
+ return res & (IP_REGISTRY_TABLE_SIZE - 1);
+}
+
+/** Find an IP registry entry if one exists for the IP address.
+ * If \a ip looks like an IPv6 address, only consider the first 64 bits
+ * of the address. Otherwise, only consider the final 32 bits.
+ * @param[in] ip IP address to search for.
+ * @return Matching registry entry, or NULL if none exists.
+ */
+static struct IPRegistryEntry* ip_registry_find(const struct irc_in_addr *ip)
+{
+ struct irc_in_addr canon;
+ struct IPRegistryEntry* entry;
+ ip_registry_canonicalize(&canon, ip);
+ entry = hashTable[ip_registry_hash(&canon)];