Kernel generates mapping change message, XFRM_MSG_MAPPING,
when a source port chage is detected on a input state with UDP
encapsulation set. Kernel generates a message for each IPsec packet
with new source port. For a high speed flow per packet mapping change
message can be excessive, and can overload the user space listener.
Introduce rate limiting for XFRM_MSG_MAPPING message to the user space.
The rate limiting is configurable via netlink, when adding a new SA or
updating it. Use the new attribute XFRMA_MTIMER_THRESH in seconds.
v1->v2 change:
update xfrm_sa_len()
v2->v3 changes:
use u32 insted unsigned long to reduce size of struct xfrm_state
fix xfrm_ompat size Reported-by: kernel test robot <lkp@intel.com>
accept XFRM_MSG_MAPPING only when XFRMA_ENCAP is present
Co-developed-by: Thomas Egerer <thomas.egerer@secunet.com>
Signed-off-by: Thomas Egerer <thomas.egerer@secunet.com>
Signed-off-by: Antony Antony <antony.antony@secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
4e484b3e96