GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

ipv6: make fragment identifications less predictable

Browse source 
IPv6 fragment identification generation is way beyond what we use for
IPv4 : It uses a single generator. Its not scalable and allows DOS
attacks.

Now inetpeer is IPv6 aware, we can use it to provide a more secure and
scalable frag ident generator (per destination, instead of system wide)

This patch :
1) defines a new secure_ipv6_id() helper
2) extends inet_getid() to provide 32bit results
3) extends ipv6_select_ident() with a new dest parameter

Reported-by: Fernando Gont <fernando@gont.com.ar>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2011-07-21 21:25:58 -07:00 • committed by David S. Miller
parent 21efcfa0ff
commit 87c48fa3b4
7 changed files with 64 additions and 22 deletions
Download patch file Download diff file Expand all files Collapse all files

15
drivers/char/random.c
View file

@ -1523,6 +1523,21 @@ __u32 secure_ip_id(__be32 daddr)
return half_md4_transform(hash, keyptr->secret);
}
__u32 secure_ipv6_id(const __be32 daddr[4])
{
const struct keydata *keyptr;
__u32 hash[4];
keyptr = get_keyptr();
hash[0] = (__force __u32)daddr[0];
hash[1] = (__force __u32)daddr[1];
hash[2] = (__force __u32)daddr[2];
hash[3] = (__force __u32)daddr[3];
return half_md4_transform(hash, keyptr->secret);
}
#ifdef CONFIG_INET
__u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,