net: defer net_secret[] initialization

Instead of feeding net_secret[] at boot time, defer the init
at the point first socket is created.

This permits some platforms to use better entropy sources than
the ones available at boot time.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2013-04-29 05:58:52 +00:00 committed by David S. Miller
parent 2d177be8e4
commit aebda156a5
3 changed files with 6 additions and 4 deletions

View File

@ -3,6 +3,7 @@
#include <linux/types.h>
extern void net_secret_init(void);
extern __u32 secure_ip_id(__be32 daddr);
extern __u32 secure_ipv6_id(const __be32 daddr[4]);
extern u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport);

View File

@ -12,12 +12,10 @@
static u32 net_secret[MD5_MESSAGE_BYTES / 4] ____cacheline_aligned;
static int __init net_secret_init(void)
void net_secret_init(void)
{
get_random_bytes(net_secret, sizeof(net_secret));
return 0;
}
late_initcall(net_secret_init);
#ifdef CONFIG_INET
static u32 seq_scale(u32 seq)

View File

@ -114,6 +114,7 @@
#include <net/inet_common.h>
#include <net/xfrm.h>
#include <net/net_namespace.h>
#include <net/secure_seq.h>
#ifdef CONFIG_IP_MROUTE
#include <linux/mroute.h>
#endif
@ -262,8 +263,10 @@ void build_ehash_secret(void)
get_random_bytes(&rnd, sizeof(rnd));
} while (rnd == 0);
if (cmpxchg(&inet_ehash_secret, 0, rnd) == 0)
if (cmpxchg(&inet_ehash_secret, 0, rnd) == 0) {
get_random_bytes(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
net_secret_init();
}
}
EXPORT_SYMBOL(build_ehash_secret);