From 1ca1b917940c24ca3d1f490118c5474168622953 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Fri, 16 Nov 2018 17:26:21 -0800 Subject: crypto: chacha20-generic - refactor to allow varying number of rounds In preparation for adding XChaCha12 support, rename/refactor chacha20-generic to support different numbers of rounds. The justification for needing XChaCha12 support is explained in more detail in the patch "crypto: chacha - add XChaCha12 support". The only difference between ChaCha{8,12,20} are the number of rounds itself; all other parts of the algorithm are the same. Therefore, remove the "20" from all definitions, structures, functions, files, etc. that will be shared by all ChaCha versions. Also make ->setkey() store the round count in the chacha_ctx (previously chacha20_ctx). The generic code then passes the round count through to chacha_block(). There will be a ->setkey() function for each explicitly allowed round count; the encrypt/decrypt functions will be the same. I decided not to do it the opposite way (same ->setkey() function for all round counts, with different encrypt/decrypt functions) because that would have required more boilerplate code in architecture-specific implementations of ChaCha and XChaCha. Reviewed-by: Ard Biesheuvel Acked-by: Martin Willi Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- arch/x86/crypto/chacha20_glue.c | 48 ++++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 24 deletions(-) (limited to 'arch/x86/crypto') diff --git a/arch/x86/crypto/chacha20_glue.c b/arch/x86/crypto/chacha20_glue.c index 9fd84fe6ec09..1e9e66509226 100644 --- a/arch/x86/crypto/chacha20_glue.c +++ b/arch/x86/crypto/chacha20_glue.c @@ -10,7 +10,7 @@ */ #include -#include +#include #include #include #include @@ -35,8 +35,8 @@ static bool chacha20_use_avx2; static unsigned int chacha20_advance(unsigned int len, unsigned int maxblocks) { - len = min(len, maxblocks * CHACHA20_BLOCK_SIZE); - return round_up(len, CHACHA20_BLOCK_SIZE) / CHACHA20_BLOCK_SIZE; + len = min(len, maxblocks * CHACHA_BLOCK_SIZE); + return round_up(len, CHACHA_BLOCK_SIZE) / CHACHA_BLOCK_SIZE; } static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src, @@ -44,38 +44,38 @@ static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src, { #ifdef CONFIG_AS_AVX2 if (chacha20_use_avx2) { - while (bytes >= CHACHA20_BLOCK_SIZE * 8) { + while (bytes >= CHACHA_BLOCK_SIZE * 8) { chacha20_8block_xor_avx2(state, dst, src, bytes); - bytes -= CHACHA20_BLOCK_SIZE * 8; - src += CHACHA20_BLOCK_SIZE * 8; - dst += CHACHA20_BLOCK_SIZE * 8; + bytes -= CHACHA_BLOCK_SIZE * 8; + src += CHACHA_BLOCK_SIZE * 8; + dst += CHACHA_BLOCK_SIZE * 8; state[12] += 8; } - if (bytes > CHACHA20_BLOCK_SIZE * 4) { + if (bytes > CHACHA_BLOCK_SIZE * 4) { chacha20_8block_xor_avx2(state, dst, src, bytes); state[12] += chacha20_advance(bytes, 8); return; } - if (bytes > CHACHA20_BLOCK_SIZE * 2) { + if (bytes > CHACHA_BLOCK_SIZE * 2) { chacha20_4block_xor_avx2(state, dst, src, bytes); state[12] += chacha20_advance(bytes, 4); return; } - if (bytes > CHACHA20_BLOCK_SIZE) { + if (bytes > CHACHA_BLOCK_SIZE) { chacha20_2block_xor_avx2(state, dst, src, bytes); state[12] += chacha20_advance(bytes, 2); return; } } #endif - while (bytes >= CHACHA20_BLOCK_SIZE * 4) { + while (bytes >= CHACHA_BLOCK_SIZE * 4) { chacha20_4block_xor_ssse3(state, dst, src, bytes); - bytes -= CHACHA20_BLOCK_SIZE * 4; - src += CHACHA20_BLOCK_SIZE * 4; - dst += CHACHA20_BLOCK_SIZE * 4; + bytes -= CHACHA_BLOCK_SIZE * 4; + src += CHACHA_BLOCK_SIZE * 4; + dst += CHACHA_BLOCK_SIZE * 4; state[12] += 4; } - if (bytes > CHACHA20_BLOCK_SIZE) { + if (bytes > CHACHA_BLOCK_SIZE) { chacha20_4block_xor_ssse3(state, dst, src, bytes); state[12] += chacha20_advance(bytes, 4); return; @@ -89,7 +89,7 @@ static void chacha20_dosimd(u32 *state, u8 *dst, const u8 *src, static int chacha20_simd(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); - struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm); + struct chacha_ctx *ctx = crypto_skcipher_ctx(tfm); u32 *state, state_buf[16 + 2] __aligned(8); struct skcipher_walk walk; int err; @@ -97,12 +97,12 @@ static int chacha20_simd(struct skcipher_request *req) BUILD_BUG_ON(CHACHA20_STATE_ALIGN != 16); state = PTR_ALIGN(state_buf + 0, CHACHA20_STATE_ALIGN); - if (req->cryptlen <= CHACHA20_BLOCK_SIZE || !may_use_simd()) - return crypto_chacha20_crypt(req); + if (req->cryptlen <= CHACHA_BLOCK_SIZE || !may_use_simd()) + return crypto_chacha_crypt(req); err = skcipher_walk_virt(&walk, req, true); - crypto_chacha20_init(state, ctx, walk.iv); + crypto_chacha_init(state, ctx, walk.iv); kernel_fpu_begin(); @@ -128,13 +128,13 @@ static struct skcipher_alg alg = { .base.cra_driver_name = "chacha20-simd", .base.cra_priority = 300, .base.cra_blocksize = 1, - .base.cra_ctxsize = sizeof(struct chacha20_ctx), + .base.cra_ctxsize = sizeof(struct chacha_ctx), .base.cra_module = THIS_MODULE, - .min_keysize = CHACHA20_KEY_SIZE, - .max_keysize = CHACHA20_KEY_SIZE, - .ivsize = CHACHA20_IV_SIZE, - .chunksize = CHACHA20_BLOCK_SIZE, + .min_keysize = CHACHA_KEY_SIZE, + .max_keysize = CHACHA_KEY_SIZE, + .ivsize = CHACHA_IV_SIZE, + .chunksize = CHACHA_BLOCK_SIZE, .setkey = crypto_chacha20_setkey, .encrypt = chacha20_simd, .decrypt = chacha20_simd, -- cgit v1.2.3