linux/net/xfrm/Kconfig

#
# XFRM configuration
#
config XFRM
       bool
       depends on NET

config XFRM_USER
	tristate "Transformation user configuration interface"
	depends on INET && XFRM
	---help---
	  Support for Transformation(XFRM) user configuration interface
	  like IPsec used by native Linux tools.

	  If unsure, say Y.

config XFRM_SUB_POLICY
	bool "Transformation sub policy support (EXPERIMENTAL)"
	depends on XFRM && EXPERIMENTAL
	---help---
	  Support sub policy for developers. By using sub policy with main
	  one, two policies can be applied to the same packet at once.
	  Policy which lives shorter time in kernel should be a sub.

	  If unsure, say N.

config NET_KEY
	tristate "PF_KEY sockets"
	select XFRM
	---help---
	  PF_KEYv2 socket family, compatible to KAME ones.
	  They are required if you are going to use IPsec tools ported
	  from KAME.

	  Say Y unless you know what you are doing.