crypto: arm/curve25519 - wire up NEON implementation

This ports the SUPERCOP implementation for usage in kernel space. In addition to the usual header, macro, and style changes required for kernel space, it makes a few small changes to the code: - The stack alignment is relaxed to 16 bytes. - Superfluous mov statements have been removed. - ldr for constants has been replaced with movw. - ldreq has been replaced with moveq. - The str epilogue has been made more idiomatic. - SIMD registers are not pushed and popped at the beginning and end. - The prologue and epilogue have been made idiomatic. - A hole has been removed from the stack, saving 32 bytes. - We write-back the base register whenever possible for vld1.8. - Some multiplications have been reordered for better A7 performance. There are more opportunities for cleanup, since this code is from qhasm, which doesn't always do the most opportune thing. But even prior to extensive hand optimizations, this code delivers significant performance improvements (given in get_cycles() per call): ----------- ------------- | generic C | this commit | ------------ ----------- ------------- | Cortex-A7 | 49136 | 22395 | ------------ ----------- ------------- | Cortex-A17 | 17326 | 4983 | ------------ ----------- ------------- Signed-off-by: Jason A. Donenfeld <[email protected]> [ardb: - move to arch/arm/crypto - wire into lib/crypto framework - implement crypto API KPP hooks ] Signed-off-by: Ard Biesheuvel <[email protected]> Signed-off-by: Herbert Xu <[email protected]>
esmil · Nov 17, 2019 · d8f1308 · d8f1308
1 parent f0fb006
commit d8f1308
Show file tree

Hide file tree

Showing 4 changed files with 287 additions and 195 deletions.
diff --git a/arch/arm/crypto/Kconfig b/arch/arm/crypto/Kconfig
@@ -142,4 +142,10 @@ config CRYPTO_NHPOLY1305_NEON
 	depends on KERNEL_MODE_NEON
 	select CRYPTO_NHPOLY1305
 
+config CRYPTO_CURVE25519_NEON
+	tristate "NEON accelerated Curve25519 scalar multiplication library"
+	depends on KERNEL_MODE_NEON
+	select CRYPTO_LIB_CURVE25519_GENERIC
+	select CRYPTO_ARCH_HAVE_LIB_CURVE25519
+
 endif
diff --git a/arch/arm/crypto/Makefile b/arch/arm/crypto/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_CRYPTO_SHA512_ARM) += sha512-arm.o
 obj-$(CONFIG_CRYPTO_CHACHA20_NEON) += chacha-neon.o
 obj-$(CONFIG_CRYPTO_POLY1305_ARM) += poly1305-arm.o
 obj-$(CONFIG_CRYPTO_NHPOLY1305_NEON) += nhpoly1305-neon.o
+obj-$(CONFIG_CRYPTO_CURVE25519_NEON) += curve25519-neon.o
 
 obj-$(CONFIG_CRYPTO_AES_ARM_CE) += aes-arm-ce.o
 obj-$(CONFIG_CRYPTO_SHA1_ARM_CE) += sha1-arm-ce.o
@@ -38,6 +39,7 @@ chacha-neon-y := chacha-scalar-core.o chacha-glue.o
 chacha-neon-$(CONFIG_KERNEL_MODE_NEON) += chacha-neon-core.o
 poly1305-arm-y := poly1305-core.o poly1305-glue.o
 nhpoly1305-neon-y := nh-neon-core.o nhpoly1305-neon-glue.o
+curve25519-neon-y := curve25519-core.o curve25519-glue.o
 
 ifdef REGENERATE_ARM_CRYPTO
 quiet_cmd_perl = PERL    $@