linux/net/xfrm
Christophe Gouault 880a6fab8f xfrm: configure policy hash table thresholds by netlink
Enable to specify local and remote prefix length thresholds for the
policy hash table via a netlink XFRM_MSG_NEWSPDINFO message.

prefix length thresholds are specified by XFRMA_SPD_IPV4_HTHRESH and
XFRMA_SPD_IPV6_HTHRESH optional attributes (struct xfrmu_spdhthresh).

example:

    struct xfrmu_spdhthresh thresh4 = {
        .lbits = 0;
        .rbits = 24;
    };
    struct xfrmu_spdhthresh thresh6 = {
        .lbits = 0;
        .rbits = 56;
    };
    struct nlmsghdr *hdr;
    struct nl_msg *msg;

    msg = nlmsg_alloc();
    hdr = nlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, XFRMA_SPD_IPV4_HTHRESH, sizeof(__u32), NLM_F_REQUEST);
    nla_put(msg, XFRMA_SPD_IPV4_HTHRESH, sizeof(thresh4), &thresh4);
    nla_put(msg, XFRMA_SPD_IPV6_HTHRESH, sizeof(thresh6), &thresh6);
    nla_send_auto(sk, msg);

The numbers are the policy selector minimum prefix lengths to put a
policy in the hash table.

- lbits is the local threshold (source address for out policies,
  destination address for in and fwd policies).

- rbits is the remote threshold (destination address for out
  policies, source address for in and fwd policies).

The default values are:

XFRMA_SPD_IPV4_HTHRESH: 32 32
XFRMA_SPD_IPV6_HTHRESH: 128 128

Dynamic re-building of the SPD is performed when the thresholds values
are changed.

The current thresholds can be read via a XFRM_MSG_GETSPDINFO request:
the kernel replies to XFRM_MSG_GETSPDINFO requests by an
XFRM_MSG_NEWSPDINFO message, with both attributes
XFRMA_SPD_IPV4_HTHRESH and XFRMA_SPD_IPV6_HTHRESH.

Signed-off-by: Christophe Gouault <christophe.gouault@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2014-09-02 13:37:56 +02:00
..
Kconfig
Makefile
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
xfrm_output.c net/xfrm/xfrm_output.c: move EXPORT_SYMBOL 2014-05-13 12:44:28 +02:00
xfrm_policy.c xfrm: configure policy hash table thresholds by netlink 2014-09-02 13:37:56 +02:00
xfrm_proc.c net: clean up snmp stats code 2014-05-07 16:06:05 -04:00
xfrm_replay.c
xfrm_state.c xfrm: remove useless hash_resize_mutex locks 2014-08-29 11:40:03 +02:00
xfrm_sysctl.c
xfrm_user.c xfrm: configure policy hash table thresholds by netlink 2014-09-02 13:37:56 +02:00