diff options
Diffstat (limited to 'arch/arm/crypto/ghash-ce-glue.c')
-rw-r--r-- | arch/arm/crypto/ghash-ce-glue.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/arch/arm/crypto/ghash-ce-glue.c b/arch/arm/crypto/ghash-ce-glue.c new file mode 100644 index 000000000..03a39fe29 --- /dev/null +++ b/arch/arm/crypto/ghash-ce-glue.c @@ -0,0 +1,320 @@ +/* + * Accelerated GHASH implementation with ARMv8 vmull.p64 instructions. + * + * Copyright (C) 2015 Linaro Ltd. <ard.biesheuvel@linaro.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#include <asm/hwcap.h> +#include <asm/neon.h> +#include <asm/simd.h> +#include <asm/unaligned.h> +#include <crypto/cryptd.h> +#include <crypto/internal/hash.h> +#include <crypto/gf128mul.h> +#include <linux/crypto.h> +#include <linux/module.h> + +MODULE_DESCRIPTION("GHASH secure hash using ARMv8 Crypto Extensions"); +MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>"); +MODULE_LICENSE("GPL v2"); + +#define GHASH_BLOCK_SIZE 16 +#define GHASH_DIGEST_SIZE 16 + +struct ghash_key { + u64 a; + u64 b; +}; + +struct ghash_desc_ctx { + u64 digest[GHASH_DIGEST_SIZE/sizeof(u64)]; + u8 buf[GHASH_BLOCK_SIZE]; + u32 count; +}; + +struct ghash_async_ctx { + struct cryptd_ahash *cryptd_tfm; +}; + +asmlinkage void pmull_ghash_update(int blocks, u64 dg[], const char *src, + struct ghash_key const *k, const char *head); + +static int ghash_init(struct shash_desc *desc) +{ + struct ghash_desc_ctx *ctx = shash_desc_ctx(desc); + + *ctx = (struct ghash_desc_ctx){}; + return 0; +} + +static int ghash_update(struct shash_desc *desc, const u8 *src, + unsigned int len) +{ + struct ghash_desc_ctx *ctx = shash_desc_ctx(desc); + unsigned int partial = ctx->count % GHASH_BLOCK_SIZE; + + ctx->count += len; + + if ((partial + len) >= GHASH_BLOCK_SIZE) { + struct ghash_key *key = crypto_shash_ctx(desc->tfm); + int blocks; + + if (partial) { + int p = GHASH_BLOCK_SIZE - partial; + + memcpy(ctx->buf + partial, src, p); + src += p; + len -= p; + } + + blocks = len / GHASH_BLOCK_SIZE; + len %= GHASH_BLOCK_SIZE; + + kernel_neon_begin(); + pmull_ghash_update(blocks, ctx->digest, src, key, + partial ? ctx->buf : NULL); + kernel_neon_end(); + src += blocks * GHASH_BLOCK_SIZE; + partial = 0; + } + if (len) + memcpy(ctx->buf + partial, src, len); + return 0; +} + +static int ghash_final(struct shash_desc *desc, u8 *dst) +{ + struct ghash_desc_ctx *ctx = shash_desc_ctx(desc); + unsigned int partial = ctx->count % GHASH_BLOCK_SIZE; + + if (partial) { + struct ghash_key *key = crypto_shash_ctx(desc->tfm); + + memset(ctx->buf + partial, 0, GHASH_BLOCK_SIZE - partial); + kernel_neon_begin(); + pmull_ghash_update(1, ctx->digest, ctx->buf, key, NULL); + kernel_neon_end(); + } + put_unaligned_be64(ctx->digest[1], dst); + put_unaligned_be64(ctx->digest[0], dst + 8); + + *ctx = (struct ghash_desc_ctx){}; + return 0; +} + +static int ghash_setkey(struct crypto_shash *tfm, + const u8 *inkey, unsigned int keylen) +{ + struct ghash_key *key = crypto_shash_ctx(tfm); + u64 a, b; + + if (keylen != GHASH_BLOCK_SIZE) { + crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + /* perform multiplication by 'x' in GF(2^128) */ + b = get_unaligned_be64(inkey); + a = get_unaligned_be64(inkey + 8); + + key->a = (a << 1) | (b >> 63); + key->b = (b << 1) | (a >> 63); + + if (b >> 63) + key->b ^= 0xc200000000000000UL; + + return 0; +} + +static struct shash_alg ghash_alg = { + .digestsize = GHASH_DIGEST_SIZE, + .init = ghash_init, + .update = ghash_update, + .final = ghash_final, + .setkey = ghash_setkey, + .descsize = sizeof(struct ghash_desc_ctx), + .base = { + .cra_name = "ghash", + .cra_driver_name = "__driver-ghash-ce", + .cra_priority = 0, + .cra_flags = CRYPTO_ALG_TYPE_SHASH | CRYPTO_ALG_INTERNAL, + .cra_blocksize = GHASH_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct ghash_key), + .cra_module = THIS_MODULE, + }, +}; + +static int ghash_async_init(struct ahash_request *req) +{ + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); + struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); + struct ahash_request *cryptd_req = ahash_request_ctx(req); + struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; + + if (!may_use_simd()) { + memcpy(cryptd_req, req, sizeof(*req)); + ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); + return crypto_ahash_init(cryptd_req); + } else { + struct shash_desc *desc = cryptd_shash_desc(cryptd_req); + struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm); + + desc->tfm = child; + desc->flags = req->base.flags; + return crypto_shash_init(desc); + } +} + +static int ghash_async_update(struct ahash_request *req) +{ + struct ahash_request *cryptd_req = ahash_request_ctx(req); + + if (!may_use_simd()) { + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); + struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); + struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; + + memcpy(cryptd_req, req, sizeof(*req)); + ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); + return crypto_ahash_update(cryptd_req); + } else { + struct shash_desc *desc = cryptd_shash_desc(cryptd_req); + return shash_ahash_update(req, desc); + } +} + +static int ghash_async_final(struct ahash_request *req) +{ + struct ahash_request *cryptd_req = ahash_request_ctx(req); + + if (!may_use_simd()) { + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); + struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); + struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; + + memcpy(cryptd_req, req, sizeof(*req)); + ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); + return crypto_ahash_final(cryptd_req); + } else { + struct shash_desc *desc = cryptd_shash_desc(cryptd_req); + return crypto_shash_final(desc, req->result); + } +} + +static int ghash_async_digest(struct ahash_request *req) +{ + struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); + struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); + struct ahash_request *cryptd_req = ahash_request_ctx(req); + struct cryptd_ahash *cryptd_tfm = ctx->cryptd_tfm; + + if (!may_use_simd()) { + memcpy(cryptd_req, req, sizeof(*req)); + ahash_request_set_tfm(cryptd_req, &cryptd_tfm->base); + return crypto_ahash_digest(cryptd_req); + } else { + struct shash_desc *desc = cryptd_shash_desc(cryptd_req); + struct crypto_shash *child = cryptd_ahash_child(cryptd_tfm); + + desc->tfm = child; + desc->flags = req->base.flags; + return shash_ahash_digest(req, desc); + } +} + +static int ghash_async_setkey(struct crypto_ahash *tfm, const u8 *key, + unsigned int keylen) +{ + struct ghash_async_ctx *ctx = crypto_ahash_ctx(tfm); + struct crypto_ahash *child = &ctx->cryptd_tfm->base; + int err; + + crypto_ahash_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_ahash_set_flags(child, crypto_ahash_get_flags(tfm) + & CRYPTO_TFM_REQ_MASK); + err = crypto_ahash_setkey(child, key, keylen); + crypto_ahash_set_flags(tfm, crypto_ahash_get_flags(child) + & CRYPTO_TFM_RES_MASK); + + return err; +} + +static int ghash_async_init_tfm(struct crypto_tfm *tfm) +{ + struct cryptd_ahash *cryptd_tfm; + struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm); + + cryptd_tfm = cryptd_alloc_ahash("__driver-ghash-ce", + CRYPTO_ALG_INTERNAL, + CRYPTO_ALG_INTERNAL); + if (IS_ERR(cryptd_tfm)) + return PTR_ERR(cryptd_tfm); + ctx->cryptd_tfm = cryptd_tfm; + crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm), + sizeof(struct ahash_request) + + crypto_ahash_reqsize(&cryptd_tfm->base)); + + return 0; +} + +static void ghash_async_exit_tfm(struct crypto_tfm *tfm) +{ + struct ghash_async_ctx *ctx = crypto_tfm_ctx(tfm); + + cryptd_free_ahash(ctx->cryptd_tfm); +} + +static struct ahash_alg ghash_async_alg = { + .init = ghash_async_init, + .update = ghash_async_update, + .final = ghash_async_final, + .setkey = ghash_async_setkey, + .digest = ghash_async_digest, + .halg.digestsize = GHASH_DIGEST_SIZE, + .halg.base = { + .cra_name = "ghash", + .cra_driver_name = "ghash-ce", + .cra_priority = 300, + .cra_flags = CRYPTO_ALG_TYPE_AHASH | CRYPTO_ALG_ASYNC, + .cra_blocksize = GHASH_BLOCK_SIZE, + .cra_type = &crypto_ahash_type, + .cra_ctxsize = sizeof(struct ghash_async_ctx), + .cra_module = THIS_MODULE, + .cra_init = ghash_async_init_tfm, + .cra_exit = ghash_async_exit_tfm, + }, +}; + +static int __init ghash_ce_mod_init(void) +{ + int err; + + if (!(elf_hwcap2 & HWCAP2_PMULL)) + return -ENODEV; + + err = crypto_register_shash(&ghash_alg); + if (err) + return err; + err = crypto_register_ahash(&ghash_async_alg); + if (err) + goto err_shash; + + return 0; + +err_shash: + crypto_unregister_shash(&ghash_alg); + return err; +} + +static void __exit ghash_ce_mod_exit(void) +{ + crypto_unregister_ahash(&ghash_async_alg); + crypto_unregister_shash(&ghash_alg); +} + +module_init(ghash_ce_mod_init); +module_exit(ghash_ce_mod_exit); |