diff options
| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2013-10-19 23:48:57 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-10-20 03:45:35 +0400 |
| commit | 1bbdceef1e535add893bf71d7b7ab102e4eb69eb (patch) | |
| tree | e2eed21c778d0a6458f8350ce5f6fbfc6c58810e /net/ipv4 | |
| parent | b23a002fc6f0c19846ee0382f019429af54a27e9 (diff) | |
| download | linux-1bbdceef1e535add893bf71d7b7ab102e4eb69eb.tar.xz | |
inet: convert inet_ehash_secret and ipv6_hash_secret to net_get_random_once
Initialize the ehash and ipv6_hash_secrets with net_get_random_once.
Each compilation unit gets its own secret now:
ipv4/inet_hashtables.o
ipv4/udp.o
ipv6/inet6_hashtables.o
ipv6/udp.o
rds/connection.o
The functions still get inlined into the hashing functions. In the fast
path we have at most two (needed in ipv6) if (unlikely(...)).
Cc: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/af_inet.c | 27 | ||||
| -rw-r--r-- | net/ipv4/inet_hashtables.c | 4 | ||||
| -rw-r--r-- | net/ipv4/udp.c | 6 |
3 files changed, 9 insertions, 28 deletions
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 4049906010f7..9433a6186f54 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -245,29 +245,6 @@ out: } EXPORT_SYMBOL(inet_listen); -u32 inet_ehash_secret __read_mostly; -EXPORT_SYMBOL(inet_ehash_secret); - -u32 ipv6_hash_secret __read_mostly; -EXPORT_SYMBOL(ipv6_hash_secret); - -/* - * inet_ehash_secret must be set exactly once, and to a non nul value - * ipv6_hash_secret must be set exactly once. - */ -void build_ehash_secret(void) -{ - u32 rnd; - - do { - get_random_bytes(&rnd, sizeof(rnd)); - } while (rnd == 0); - - if (cmpxchg(&inet_ehash_secret, 0, rnd) == 0) - get_random_bytes(&ipv6_hash_secret, sizeof(ipv6_hash_secret)); -} -EXPORT_SYMBOL(build_ehash_secret); - /* * Create an inet socket. */ @@ -284,10 +261,6 @@ static int inet_create(struct net *net, struct socket *sock, int protocol, int try_loading_module = 0; int err; - if (unlikely(!inet_ehash_secret)) - if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) - build_ehash_secret(); - sock->state = SS_UNCONNECTED; /* Look for the requested type/protocol pair. */ diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index 18aa668d0cc9..8b9cf279450d 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -28,6 +28,10 @@ static unsigned int inet_ehashfn(struct net *net, const __be32 laddr, const __u16 lport, const __be32 faddr, const __be16 fport) { + static u32 inet_ehash_secret __read_mostly; + + net_get_random_once(&inet_ehash_secret, sizeof(inet_ehash_secret)); + return __inet_ehashfn(laddr, lport, faddr, fport, inet_ehash_secret + net_hash_mix(net)); } diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index b4437c7db6ce..89909dd730dd 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -411,8 +411,12 @@ static unsigned int udp_ehashfn(struct net *net, const __be32 laddr, const __u16 lport, const __be32 faddr, const __be16 fport) { + static u32 udp_ehash_secret __read_mostly; + + net_get_random_once(&udp_ehash_secret, sizeof(udp_ehash_secret)); + return __inet_ehashfn(laddr, lport, faddr, fport, - inet_ehash_secret + net_hash_mix(net)); + udp_ehash_secret + net_hash_mix(net)); } |