From: Eric Biggers <ebiggers@xxxxxxxxxx> Since the Linux RNG no longer uses sha1_transform(), the SHA-1 library is no longer needed unconditionally. Make it possible to build the Linux kernel without the SHA-1 library by putting it behind a kconfig option, and selecting this new option from the kconfig options that gate the remaining users: CRYPTO_SHA1 for crypto/sha1_generic.c, BPF for kernel/bpf/core.c, and IPV6 for net/ipv6/addrconf.c. Unfortunately, since BPF is selected by NET, for now this can only make a difference for kernels built without networking support. Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> --- crypto/Kconfig | 1 + init/Kconfig | 1 + lib/crypto/Kconfig | 3 +++ lib/crypto/Makefile | 3 ++- net/ipv6/Kconfig | 1 + 5 files changed, 8 insertions(+), 1 deletion(-) diff --git a/crypto/Kconfig b/crypto/Kconfig index 59489a300cd100..bf15ca5eb9d367 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -880,6 +880,7 @@ config CRYPTO_RMD160 config CRYPTO_SHA1 tristate "SHA1 digest algorithm" select CRYPTO_HASH + select CRYPTO_LIB_SHA1 help SHA-1 secure hash standard (FIPS 180-1/DFIPS 180-2). diff --git a/init/Kconfig b/init/Kconfig index c984afc489dead..d8d0b4bdfe4195 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1472,6 +1472,7 @@ config HAVE_PCSPKR_PLATFORM # interpreter that classic socket filters depend on config BPF bool + select CRYPTO_LIB_SHA1 menuconfig EXPERT bool "Configure standard kernel features (expert users)" diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig index 2082af43d51fbe..9ff549f63540fa 100644 --- a/lib/crypto/Kconfig +++ b/lib/crypto/Kconfig @@ -121,6 +121,9 @@ config CRYPTO_LIB_CHACHA20POLY1305 select CRYPTO_LIB_POLY1305 select CRYPTO_ALGAPI +config CRYPTO_LIB_SHA1 + tristate + config CRYPTO_LIB_SHA256 tristate diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile index d28111ba54fcb2..919cbb2c220d61 100644 --- a/lib/crypto/Makefile +++ b/lib/crypto/Makefile @@ -34,7 +34,8 @@ libpoly1305-y := poly1305-donna32.o libpoly1305-$(CONFIG_ARCH_SUPPORTS_INT128) := poly1305-donna64.o libpoly1305-y += poly1305.o -obj-y += sha1.o +obj-$(CONFIG_CRYPTO_LIB_SHA1) += libsha1.o +libsha1-y := sha1.o obj-$(CONFIG_CRYPTO_LIB_SHA256) += libsha256.o libsha256-y := sha256.o diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig index bf2e5e5fe14273..658bfed1df8b17 100644 --- a/net/ipv6/Kconfig +++ b/net/ipv6/Kconfig @@ -7,6 +7,7 @@ menuconfig IPV6 tristate "The IPv6 protocol" default y + select CRYPTO_LIB_SHA1 help Support for IP version 6 (IPv6). -- 2.37.0
