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authorHannes Frederic Sowa <hannes@stressinduktion.org>2013-10-19 21:48:57 +0200
committerDavid S. Miller <davem@davemloft.net>2013-10-19 19:45:35 -0400
commit1bbdceef1e535add893bf71d7b7ab102e4eb69eb (patch)
treee2eed21c778d0a6458f8350ce5f6fbfc6c58810e /net
parentinet: split syncookie keys for ipv4 and ipv6 and initialize with net_get_random_once (diff)
downloadlinux-dev-1bbdceef1e535add893bf71d7b7ab102e4eb69eb.tar.xz
linux-dev-1bbdceef1e535add893bf71d7b7ab102e4eb69eb.zip
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')
-rw-r--r--net/ipv4/af_inet.c27
-rw-r--r--net/ipv4/inet_hashtables.c4
-rw-r--r--net/ipv4/udp.c6
-rw-r--r--net/ipv6/af_inet6.c5
-rw-r--r--net/ipv6/inet6_hashtables.c15
-rw-r--r--net/ipv6/udp.c17
-rw-r--r--net/rds/connection.c12
7 files changed, 44 insertions, 42 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));
}
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index a2cb07cd3850..20af1fb81c83 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -110,11 +110,6 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol,
int try_loading_module = 0;
int err;
- if (sock->type != SOCK_RAW &&
- sock->type != SOCK_DGRAM &&
- !inet_ehash_secret)
- build_ehash_secret();
-
/* Look for the requested type/protocol pair. */
lookup_protocol:
err = -ESOCKTNOSUPPORT;
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index fa7dd3856c55..262e13c02ec2 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -29,10 +29,19 @@ static unsigned int inet6_ehashfn(struct net *net,
const struct in6_addr *faddr,
const __be16 fport)
{
- const u32 lhash = (__force u32)laddr->s6_addr32[3];
- const u32 fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);
+ static u32 inet6_ehash_secret __read_mostly;
+ static u32 ipv6_hash_secret __read_mostly;
+
+ u32 lhash, fhash;
+
+ net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret));
+ net_get_random_once(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
+
+ lhash = (__force u32)laddr->s6_addr32[3];
+ fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);
+
return __inet6_ehashfn(lhash, lport, fhash, fport,
- inet_ehash_secret + net_hash_mix(net));
+ inet6_ehash_secret + net_hash_mix(net));
}
static int inet6_sk_ehashfn(const struct sock *sk)
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 324bd36c23bc..44fc4e3d661f 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -59,10 +59,21 @@ static unsigned int udp6_ehashfn(struct net *net,
const struct in6_addr *faddr,
const __be16 fport)
{
- const u32 lhash = (__force u32)laddr->s6_addr32[3];
- const u32 fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);
+ static u32 udp6_ehash_secret __read_mostly;
+ static u32 udp_ipv6_hash_secret __read_mostly;
+
+ u32 lhash, fhash;
+
+ net_get_random_once(&udp6_ehash_secret,
+ sizeof(udp6_ehash_secret));
+ net_get_random_once(&udp_ipv6_hash_secret,
+ sizeof(udp_ipv6_hash_secret));
+
+ lhash = (__force u32)laddr->s6_addr32[3];
+ fhash = __ipv6_addr_jhash(faddr, udp_ipv6_hash_secret);
+
return __inet6_ehashfn(lhash, lport, fhash, fport,
- inet_ehash_secret + net_hash_mix(net));
+ udp_ipv6_hash_secret + net_hash_mix(net));
}
int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
diff --git a/net/rds/connection.c b/net/rds/connection.c
index 45e23660437a..378c3a6acf84 100644
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -51,10 +51,16 @@ static struct kmem_cache *rds_conn_slab;
static struct hlist_head *rds_conn_bucket(__be32 laddr, __be32 faddr)
{
+ static u32 rds_hash_secret __read_mostly;
+
+ unsigned long hash;
+
+ net_get_random_once(&rds_hash_secret, sizeof(rds_hash_secret));
+
/* Pass NULL, don't need struct net for hash */
- unsigned long hash = __inet_ehashfn(be32_to_cpu(laddr), 0,
- be32_to_cpu(faddr), 0,
- inet_ehash_secret);
+ hash = __inet_ehashfn(be32_to_cpu(laddr), 0,
+ be32_to_cpu(faddr), 0,
+ rds_hash_secret);
return &rds_conn_hash[hash & RDS_CONNECTION_HASH_MASK];
}