diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.15/950-0353-Assign-crypto-aliases-to-different-AES-implementatio.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.15/950-0353-Assign-crypto-aliases-to-different-AES-implementatio.patch | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.15/950-0353-Assign-crypto-aliases-to-different-AES-implementatio.patch b/target/linux/bcm27xx/patches-5.15/950-0353-Assign-crypto-aliases-to-different-AES-implementatio.patch new file mode 100644 index 0000000000..7af13d4023 --- /dev/null +++ b/target/linux/bcm27xx/patches-5.15/950-0353-Assign-crypto-aliases-to-different-AES-implementatio.patch @@ -0,0 +1,105 @@ +From d4a2fa7b58d3891544c9b7e41e92f17774ad7d1f Mon Sep 17 00:00:00 2001 +From: Ben Avison <bavison@riscosopen.org> +Date: Mon, 8 Mar 2021 15:32:25 +0000 +Subject: [PATCH] Assign crypto aliases to different AES implementation + modules + +The kernel modules aes-neon-blk and aes-neon-bs perform poorly, at least on +Cortex-A72 without crypto extensions. In fact, aes-arm64 outperforms them +on benchmarks, despite it being a simpler implementation (only accelerating +the single-block AES cipher). + +For modes of operation where multiple cipher blocks can be processed in +parallel, aes-neon-bs outperforms aes-neon-blk by around 60-70% and aes-arm64 +is another 10-20% faster still. But the difference is even more marked with +modes of operation with dependencies between neighbouring blocks, such as +CBC encryption, which defeat parallelism: in these cases, aes-arm64 is +typically around 250% faster than either aes-neon-blk or aes-neon-bs. + +The key trade-off with aes-arm64 is that the look-up tables are situated in +RAM. This leaves them potentially open to cache timing attacks. The two other +modules, by contrast, load the look-up tables into NEON registers and so are +able to perform in constant time. + +This patch aims to load aes-arm64 more often. + +If none of the currently-loaded crypto modules implement a given algorithm, +a new one is typically selected for loading using a platform-neutral alias +describing the required algorithm. To enable users to still +load aes-neon-blk or aes-neon-bs if they really want them, while still +ensuring that aes-arm64 is usually selected, remove the aliases from +aes-neonbs-glue.c and aes-glue.c and apply them to aes-cipher-glue.c, but +still build the two NEON modules. + +Since aes-glue.c can also be used to build aes-ce-blk, leave them enabled +if USE_V8_CRYPTO_EXTENSIONS is defined, to ensure they are selected if we +in future use a CPU which has the crypto extensions enabled. + +Note that the algorithm priority specifiers are unchanged, so if +aes-neon-bs is loaded at the same time as aes-arm64, the former will be +used in preference. However, aes-neon-blk and aes-arm64 have tied priority, +so whichever module was loaded first will be used (assuming aes-neon-bs is +not loaded). + +Signed-off-by: Ben Avison <bavison@riscosopen.org> +--- + arch/arm64/crypto/aes-cipher-glue.c | 10 ++++++++++ + arch/arm64/crypto/aes-glue.c | 4 ++-- + arch/arm64/crypto/aes-neonbs-glue.c | 5 ----- + 3 files changed, 12 insertions(+), 7 deletions(-) + +--- a/arch/arm64/crypto/aes-cipher-glue.c ++++ b/arch/arm64/crypto/aes-cipher-glue.c +@@ -9,6 +9,16 @@ + #include <linux/crypto.h> + #include <linux/module.h> + ++MODULE_ALIAS_CRYPTO("ecb(aes)"); ++MODULE_ALIAS_CRYPTO("cbc(aes)"); ++MODULE_ALIAS_CRYPTO("ctr(aes)"); ++MODULE_ALIAS_CRYPTO("xts(aes)"); ++MODULE_ALIAS_CRYPTO("cts(cbc(aes))"); ++MODULE_ALIAS_CRYPTO("essiv(cbc(aes),sha256)"); ++MODULE_ALIAS_CRYPTO("cmac(aes)"); ++MODULE_ALIAS_CRYPTO("xcbc(aes)"); ++MODULE_ALIAS_CRYPTO("cbcmac(aes)"); ++ + asmlinkage void __aes_arm64_encrypt(u32 *rk, u8 *out, const u8 *in, int rounds); + asmlinkage void __aes_arm64_decrypt(u32 *rk, u8 *out, const u8 *in, int rounds); + +--- a/arch/arm64/crypto/aes-glue.c ++++ b/arch/arm64/crypto/aes-glue.c +@@ -57,17 +57,17 @@ MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS + #define aes_mac_update neon_aes_mac_update + MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 NEON"); + #endif +-#if defined(USE_V8_CRYPTO_EXTENSIONS) || !IS_ENABLED(CONFIG_CRYPTO_AES_ARM64_BS) ++#if defined(USE_V8_CRYPTO_EXTENSIONS) + MODULE_ALIAS_CRYPTO("ecb(aes)"); + MODULE_ALIAS_CRYPTO("cbc(aes)"); + MODULE_ALIAS_CRYPTO("ctr(aes)"); + MODULE_ALIAS_CRYPTO("xts(aes)"); +-#endif + MODULE_ALIAS_CRYPTO("cts(cbc(aes))"); + MODULE_ALIAS_CRYPTO("essiv(cbc(aes),sha256)"); + MODULE_ALIAS_CRYPTO("cmac(aes)"); + MODULE_ALIAS_CRYPTO("xcbc(aes)"); + MODULE_ALIAS_CRYPTO("cbcmac(aes)"); ++#endif + + MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); + MODULE_LICENSE("GPL v2"); +--- a/arch/arm64/crypto/aes-neonbs-glue.c ++++ b/arch/arm64/crypto/aes-neonbs-glue.c +@@ -18,11 +18,6 @@ + MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); + MODULE_LICENSE("GPL v2"); + +-MODULE_ALIAS_CRYPTO("ecb(aes)"); +-MODULE_ALIAS_CRYPTO("cbc(aes)"); +-MODULE_ALIAS_CRYPTO("ctr(aes)"); +-MODULE_ALIAS_CRYPTO("xts(aes)"); +- + asmlinkage void aesbs_convert_key(u8 out[], u32 const rk[], int rounds); + + asmlinkage void aesbs_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[], |