diff options
Diffstat (limited to 'arch/arm/crypto/sha256_neon_glue.c')
| -rw-r--r-- | arch/arm/crypto/sha256_neon_glue.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/arch/arm/crypto/sha256_neon_glue.c b/arch/arm/crypto/sha256_neon_glue.c new file mode 100644 index 000000000000..c4da10090eee --- /dev/null +++ b/arch/arm/crypto/sha256_neon_glue.c @@ -0,0 +1,172 @@ +/* + * Glue code for the SHA256 Secure Hash Algorithm assembly implementation + * using NEON instructions. + * + * Copyright © 2015 Google Inc. + * + * This file is based on sha512_neon_glue.c: + * Copyright © 2014 Jussi Kivilinna <jussi.kivilinna@iki.fi> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include <crypto/internal/hash.h> +#include <linux/cryptohash.h> +#include <linux/types.h> +#include <linux/string.h> +#include <crypto/sha.h> +#include <asm/byteorder.h> +#include <asm/simd.h> +#include <asm/neon.h> +#include "sha256_glue.h" + +asmlinkage void sha256_block_data_order_neon(u32 *digest, const void *data, + unsigned int num_blks); + + +static int __sha256_neon_update(struct shash_desc *desc, const u8 *data, + unsigned int len, unsigned int partial) +{ + struct sha256_state *sctx = shash_desc_ctx(desc); + unsigned int done = 0; + + sctx->count += len; + + if (partial) { + done = SHA256_BLOCK_SIZE - partial; + memcpy(sctx->buf + partial, data, done); + sha256_block_data_order_neon(sctx->state, sctx->buf, 1); + } + + if (len - done >= SHA256_BLOCK_SIZE) { + const unsigned int rounds = (len - done) / SHA256_BLOCK_SIZE; + + sha256_block_data_order_neon(sctx->state, data + done, rounds); + done += rounds * SHA256_BLOCK_SIZE; + } + + memcpy(sctx->buf, data + done, len - done); + + return 0; +} + +static int sha256_neon_update(struct shash_desc *desc, const u8 *data, + unsigned int len) +{ + struct sha256_state *sctx = shash_desc_ctx(desc); + unsigned int partial = sctx->count % SHA256_BLOCK_SIZE; + int res; + + /* Handle the fast case right here */ + if (partial + len < SHA256_BLOCK_SIZE) { + sctx->count += len; + memcpy(sctx->buf + partial, data, len); + + return 0; + } + + if (!may_use_simd()) { + res = __sha256_update(desc, data, len, partial); + } else { + kernel_neon_begin(); + res = __sha256_neon_update(desc, data, len, partial); + kernel_neon_end(); + } + + return res; +} + +/* Add padding and return the message digest. */ +static int sha256_neon_final(struct shash_desc *desc, u8 *out) +{ + struct sha256_state *sctx = shash_desc_ctx(desc); + unsigned int i, index, padlen; + __be32 *dst = (__be32 *)out; + __be64 bits; + static const u8 padding[SHA256_BLOCK_SIZE] = { 0x80, }; + + /* save number of bits */ + bits = cpu_to_be64(sctx->count << 3); + + /* Pad out to 56 mod 64 and append length */ + index = sctx->count % SHA256_BLOCK_SIZE; + padlen = (index < 56) ? (56 - index) : ((SHA256_BLOCK_SIZE+56)-index); + + if (!may_use_simd()) { + sha256_update(desc, padding, padlen); + sha256_update(desc, (const u8 *)&bits, sizeof(bits)); + } else { + kernel_neon_begin(); + /* We need to fill a whole block for __sha256_neon_update() */ + if (padlen <= 56) { + sctx->count += padlen; + memcpy(sctx->buf + index, padding, padlen); + } else { + __sha256_neon_update(desc, padding, padlen, index); + } + __sha256_neon_update(desc, (const u8 *)&bits, + sizeof(bits), 56); + kernel_neon_end(); + } + + /* Store state in digest */ + for (i = 0; i < 8; i++) + dst[i] = cpu_to_be32(sctx->state[i]); + + /* Wipe context */ + memzero_explicit(sctx, sizeof(*sctx)); + + return 0; +} + +static int sha224_neon_final(struct shash_desc *desc, u8 *out) +{ + u8 D[SHA256_DIGEST_SIZE]; + + sha256_neon_final(desc, D); + + memcpy(out, D, SHA224_DIGEST_SIZE); + memzero_explicit(D, SHA256_DIGEST_SIZE); + + return 0; +} + +struct shash_alg sha256_neon_algs[] = { { + .digestsize = SHA256_DIGEST_SIZE, + .init = sha256_init, + .update = sha256_neon_update, + .final = sha256_neon_final, + .export = sha256_export, + .import = sha256_import, + .descsize = sizeof(struct sha256_state), + .statesize = sizeof(struct sha256_state), + .base = { + .cra_name = "sha256", + .cra_driver_name = "sha256-neon", + .cra_priority = 250, + .cra_flags = CRYPTO_ALG_TYPE_SHASH, + .cra_blocksize = SHA256_BLOCK_SIZE, + .cra_module = THIS_MODULE, + } +}, { + .digestsize = SHA224_DIGEST_SIZE, + .init = sha224_init, + .update = sha256_neon_update, + .final = sha224_neon_final, + .export = sha256_export, + .import = sha256_import, + .descsize = sizeof(struct sha256_state), + .statesize = sizeof(struct sha256_state), + .base = { + .cra_name = "sha224", + .cra_driver_name = "sha224-neon", + .cra_priority = 250, + .cra_flags = CRYPTO_ALG_TYPE_SHASH, + .cra_blocksize = SHA224_BLOCK_SIZE, + .cra_module = THIS_MODULE, + } +} }; |