linux/net/xfrm
Christophe Gouault b58555f176 xfrm: hash prefixed policies based on preflen thresholds
The idea is an extension of the current policy hashing.

Today only non-prefixed policies are stored in a hash table. This
patch relaxes the constraints, and hashes policies whose prefix
lengths are greater or equal to a configurable threshold.

Each hash table (one per direction) maintains its own set of IPv4 and
IPv6 thresholds (dbits4, sbits4, dbits6, sbits6), by default (32, 32,
128, 128).

Example, if the output hash table is configured with values (16, 24,
56, 64):

ip xfrm policy add dir out src 10.22.0.0/20 dst 10.24.1.0/24 ... => hashed
ip xfrm policy add dir out src 10.22.0.0/16 dst 10.24.1.1/32 ... => hashed
ip xfrm policy add dir out src 10.22.0.0/16 dst 10.24.0.0/16 ... => unhashed

ip xfrm policy add dir out \
    src 3ffe:304:124:2200::/60 dst 3ffe:304:124:2401::/64 ...    => hashed
ip xfrm policy add dir out \
    src 3ffe:304:124:2200::/56 dst 3ffe:304:124:2401::2/128 ...  => hashed
ip xfrm policy add dir out \
    src 3ffe:304:124:2200::/56 dst 3ffe:304:124:2400::/56 ...    => unhashed

The high order bits of the addresses (up to the threshold) are used to
compute the hash key.

Signed-off-by: Christophe Gouault <christophe.gouault@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2014-09-02 13:29:44 +02:00
..
Kconfig net/xfrm: remove depends on CONFIG_EXPERIMENTAL 2013-01-11 11:40:03 -08:00
Makefile xfrm: make xfrm_algo.c a module 2012-05-15 13:13:34 -04:00
xfrm_algo.c net: move pskb_put() to core code 2013-11-07 19:28:58 -05:00
xfrm_hash.c
xfrm_hash.h xfrm: hash prefixed policies based on preflen thresholds 2014-09-02 13:29:44 +02:00
xfrm_input.c xfrm: Introduce xfrm_input_afinfo to access the the callbacks properly 2014-03-14 07:28:07 +01:00
xfrm_ipcomp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-11-04 13:48:30 -05:00
xfrm_output.c net/xfrm/xfrm_output.c: move EXPORT_SYMBOL 2014-05-13 12:44:28 +02:00
xfrm_policy.c xfrm: hash prefixed policies based on preflen thresholds 2014-09-02 13:29:44 +02:00
xfrm_proc.c net: clean up snmp stats code 2014-05-07 16:06:05 -04:00
xfrm_replay.c xfrm: Fix aevent generation for each received packet 2013-09-25 07:32:48 +02:00
xfrm_state.c xfrm: remove useless hash_resize_mutex locks 2014-08-29 11:40:03 +02:00
xfrm_sysctl.c net: Don't export sysctls to unprivileged users 2012-11-18 20:30:55 -05:00
xfrm_user.c xfrm: Fix installation of AH IPsec SAs 2014-06-30 07:42:12 +02:00