nuttx/drivers/crypto/Kconfig

#
# For a description of the syntax of this configuration file,
# see the file kconfig-language.txt in the NuttX tools repository.
#

config ARCH_HAVE_RNG
	bool

config DEV_RANDOM
	bool "Enable /dev/random"
	default y
	depends on ARCH_HAVE_RNG
	---help---
		Enable support for /dev/random provided by a hardware TRNG.

config DEV_URANDOM
	bool "Enable /dev/urandom"
	default n
	---help---
		Enable support for /dev/urandom provided by either a hardware TRNG or
		by a software PRNG implementation.

		NOTE:  This option may not be cryptographially secure and should not
		be enabled if you are concerned about cyptographically secure
		pseudo-random numbers (CPRNG) and do not know the characteristics
		of the software PRNG implementation!

if DEV_URANDOM

choice
	prompt "/dev/urandom algorithm"
	default DEV_URANDOM_ARCH if ARCH_HAVE_RNG
	default DEV_URANDOM_XORSHIFT128 if !ARCH_HAVE_RNG

config DEV_URANDOM_XORSHIFT128
	bool "xorshift128"
	---help---
		xorshift128 is a pseudorandom number generator that is simple,
		portable, and can also be used on 8-bit and 16-bit MCUs.

		NOTE: Not cyptographically secure

config DEV_URANDOM_CONGRUENTIAL
	bool "Congruential"
	---help---
		Use the same congruential general used with srand().  This algorithm
		is computationally more intense and uses double precision floating
		point.  NOTE: Good randomness from the congruential generator also
		requires that you also select CONFIG_LIBC_RAND_ORDER > 2

		NOTE: Not cyptographically secure

config DEV_URANDOM_RANDOM_POOL
	bool "Entropy pool"
	depends on CRYPTO_RANDOM_POOL
	---help---
		Use the entropy pool CPRNG output for urandom algorithm.

		NOTE: May or may not be cyptographically secure, depending upon the
		quality entropy available to entropy pool.

config DEV_URANDOM_ARCH
	bool "Architecture-specific"
	depends on ARCH_HAVE_RNG
	---help---
		The implementation of /dev/urandom is provided in archtecture-
		specific logic using hardware TRNG logic.  architecture-specific
		logic must provide the whole implementation in this case, including
		the function devurandom_register().  In this case, /dev/urandom may
		refer to the same driver as /dev/random.

		NOTE: May or may not be cyptographically secure, depending upon the
		implementation.

endchoice # /dev/urandom algorithm
endif # DEV_URANDOM

menuconfig DEV_SE05X
	bool "Enable secure element (SE05X)"
	depends on I2C
	depends on CRYPTO
	default n
	---help---
		Enable support for /dev/se05x secure element provided by NXP SE050
		or SE051

if DEV_SE05X

choice
	prompt "Channel communication interface"
	default DEV_SE05X_PLAIN
	---help---
		Select authentication method

config DEV_SE05X_SCP03
	bool "SCP03 secure channel (TBI)"
	select CRYPTO_RANDOM_POOL
	select CRYPTO_AES

config DEV_SE05X_PLAIN
	bool "plain communication"

endchoice

config DEV_SE05X_SCP03_KEY_FILE
	string "SCP03 keys"
	depends on DEV_SE05X_SCP03
	default "/host/path/to/key_file"
	---help---
		Specify file containing the keys needed with SCP03 channel authentication.
		Location may be relative to the NuttX root folder. File should contain
		the definitions for SCP03_ENC_KEY, SCP03_MAC_KEY and SCP03_DEK_KEY as
		byte array initializers.

choice SE05X_LOG_LEVEL
	prompt "SE05x debug log level"
	default SE05X_LOG_NONE
	---help---
		The SE05x log is divided into the following levels: ERROR,WARNING,INFO,DEBUG.

	config SE05X_LOG_NONE
		bool "No output"
	config SE05X_LOG_ERROR
		bool "Error"
	config SE05X_LOG_WARNING
		bool "Warning"
	config SE05X_LOG_INFO
		bool "Info"
	config SE05X_LOG_DEBUG
		bool "Debug"
endchoice

endif #DEV_SE05X