Commit c7dcb041 authored Nov 13, 2025 by Eric Biggers Committed by Herbert Xu Nov 22, 2025

crypto: ansi_cprng - Remove unused ansi_cprng algorithm

Remove ansi_cprng, since it's obsolete and unused, as confirmed at
https://lore.kernel.org/r/aQxpnckYMgAAOLpZ@gondor.apana.org.au/



This was originally added in 2008, apparently as a FIPS approved random
number generator.  Whether this has ever belonged upstream is
questionable.  Either way, ansi_cprng is no longer usable for this
purpose, since it's been superseded by the more modern algorithms in
crypto/drbg.c, and FIPS itself no longer allows it.  (NIST SP 800-131A
Rev 1 (2015) says that RNGs based on ANSI X9.31 will be disallowed after
2015.  NIST SP 800-131A Rev 2 (2019) confirms they are now disallowed.)

Therefore, there is no reason to keep it around.

Suggested-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Haotian Zhang <vulab@iscas.ac.cn>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

parent 79492d5a

Documentation/crypto/userspace-if.rst

+3 −4

Original line number	Diff line number	Diff line
		@@ -302,10 +302,9 @@ follows:


		Depending on the RNG type, the RNG must be seeded. The seed is provided
		using the setsockopt interface to set the key. For example, the
		ansi_cprng requires a seed. The DRBGs do not require a seed, but may be
		seeded. The seed is also known as a Personalization String in NIST SP 800-90A
		standard.
		using the setsockopt interface to set the key. The SP800-90A DRBGs do
		not require a seed, but may be seeded. The seed is also known as a
		Personalization String in NIST SP 800-90A standard.

		Using the read()/recvmsg() system calls, random numbers can be obtained.
		The kernel generates at most 128 bytes in one call. If user space

MAINTAINERS

+0 −1

Original line number	Diff line number	Diff line
		@@ -6605,7 +6605,6 @@ CRYPTOGRAPHIC RANDOM NUMBER GENERATOR
		M: Neil Horman <nhorman@tuxdriver.com>
		L: linux-crypto@vger.kernel.org
		S: Maintained
		F: crypto/ansi_cprng.c
		F: crypto/rng.c

		CS3308 MEDIA DRIVER

arch/arm/configs/axm55xx_defconfig

+0 −1

Original line number	Diff line number	Diff line
		@@ -233,4 +233,3 @@ CONFIG_RCU_CPU_STALL_TIMEOUT=60
		CONFIG_DEBUG_USER=y
		CONFIG_CRYPTO_GCM=y
		CONFIG_CRYPTO_SHA256=y
		# CONFIG_CRYPTO_ANSI_CPRNG is not set

arch/arm/configs/clps711x_defconfig

+0 −1

Original line number	Diff line number	Diff line
		@@ -75,5 +75,4 @@ CONFIG_MINIX_FS=y
		CONFIG_DEBUG_USER=y
		CONFIG_DEBUG_LL=y
		CONFIG_EARLY_PRINTK=y
		# CONFIG_CRYPTO_ANSI_CPRNG is not set
		# CONFIG_CRYPTO_HW is not set

arch/arm/configs/dove_defconfig

+0 −1

Original line number	Diff line number	Diff line
		@@ -126,7 +126,6 @@ CONFIG_CRYPTO_SHA256=y
		CONFIG_CRYPTO_SHA512=y
		CONFIG_CRYPTO_DEFLATE=y
		CONFIG_CRYPTO_LZO=y
		# CONFIG_CRYPTO_ANSI_CPRNG is not set
		CONFIG_CRYPTO_DEV_MARVELL_CESA=y
		CONFIG_PRINTK_TIME=y
		# CONFIG_DEBUG_BUGVERBOSE is not set