lockd: Support AF_INET6 when hashing addresses in nlm_lookup_host

Adopt an approach similar to the RPC server's auth cache (from Aurelien
Charbon and Brian Haley).

Note nlm_lookup_host()'s existing IP address hash function has the same
issue with correctness on little-endian systems as the original IPv4 auth
cache hash function, so I've also updated it with a hash function similar
to the new auth cache hash function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This commit is contained in:
Chuck Lever 2008-09-03 14:36:08 -04:00 коммит произвёл J. Bruce Fields
Родитель 781b61a6f4
Коммит ede2fea099
1 изменённых файлов: 43 добавлений и 6 удалений

Просмотреть файл

@ -22,7 +22,6 @@
#define NLMDBG_FACILITY NLMDBG_HOSTCACHE
#define NLM_HOST_NRHASH 32
#define NLM_ADDRHASH(addr) (ntohl(addr) & (NLM_HOST_NRHASH-1))
#define NLM_HOST_REBIND (60 * HZ)
#define NLM_HOST_EXPIRE (300 * HZ)
#define NLM_HOST_COLLECT (120 * HZ)
@ -40,6 +39,48 @@ static struct nsm_handle * nsm_find(const struct sockaddr_in *sin,
const char *hostname,
unsigned int hostname_len);
/*
* Hash function must work well on big- and little-endian platforms
*/
static unsigned int __nlm_hash32(const __be32 n)
{
unsigned int hash = (__force u32)n ^ ((__force u32)n >> 16);
return hash ^ (hash >> 8);
}
static unsigned int __nlm_hash_addr4(const struct sockaddr *sap)
{
const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
return __nlm_hash32(sin->sin_addr.s_addr);
}
static unsigned int __nlm_hash_addr6(const struct sockaddr *sap)
{
const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
const struct in6_addr addr = sin6->sin6_addr;
return __nlm_hash32(addr.s6_addr32[0]) ^
__nlm_hash32(addr.s6_addr32[1]) ^
__nlm_hash32(addr.s6_addr32[2]) ^
__nlm_hash32(addr.s6_addr32[3]);
}
static unsigned int nlm_hash_address(const struct sockaddr *sap)
{
unsigned int hash;
switch (sap->sa_family) {
case AF_INET:
hash = __nlm_hash_addr4(sap);
break;
case AF_INET6:
hash = __nlm_hash_addr6(sap);
break;
default:
hash = 0;
}
return hash & (NLM_HOST_NRHASH - 1);
}
static void nlm_clear_port(struct sockaddr *sap)
{
switch (sap->sa_family) {
@ -92,16 +133,12 @@ static struct nlm_host *nlm_lookup_host(int server,
struct hlist_node *pos;
struct nlm_host *host;
struct nsm_handle *nsm = NULL;
int hash;
dprintk("lockd: nlm_lookup_host(proto=%d, vers=%u,"
" my role is %s, hostname=%.*s)\n",
proto, version, server ? "server" : "client",
hostname_len, hostname ? hostname : "<none>");
hash = NLM_ADDRHASH(sin->sin_addr.s_addr);
/* Lock hash table */
mutex_lock(&nlm_host_mutex);
if (time_after_eq(jiffies, next_gc))
@ -114,7 +151,7 @@ static struct nlm_host *nlm_lookup_host(int server,
* different NLM rpc_clients into one single nlm_host object.
* This would allow us to have one nlm_host per address.
*/
chain = &nlm_hosts[hash];
chain = &nlm_hosts[nlm_hash_address((struct sockaddr *)sin)];
hlist_for_each_entry(host, pos, chain, h_hash) {
if (!nlm_cmp_addr(nlm_addr(host), (struct sockaddr *)sin))
continue;