diff options
Diffstat (limited to 'drivers/crypto/vmx/ghash.c')
| -rw-r--r-- | drivers/crypto/vmx/ghash.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/crypto/vmx/ghash.c b/drivers/crypto/vmx/ghash.c new file mode 100644 index 000000000..2d1a8cd35 --- /dev/null +++ b/drivers/crypto/vmx/ghash.c @@ -0,0 +1,185 @@ +// SPDX-License-Identifier: GPL-2.0 +/** + * GHASH routines supporting VMX instructions on the Power 8 + * + * Copyright (C) 2015, 2019 International Business Machines Inc. + * + * Author: Marcelo Henrique Cerri <mhcerri@br.ibm.com> + * + * Extended by Daniel Axtens <dja@axtens.net> to replace the fallback + * mechanism. The new approach is based on arm64 code, which is: + * Copyright (C) 2014 - 2018 Linaro Ltd. <ard.biesheuvel@linaro.org> + */ + +#include <linux/types.h> +#include <linux/err.h> +#include <linux/crypto.h> +#include <linux/delay.h> +#include <linux/hardirq.h> +#include <asm/switch_to.h> +#include <crypto/aes.h> +#include <crypto/ghash.h> +#include <crypto/scatterwalk.h> +#include <crypto/internal/hash.h> +#include <crypto/b128ops.h> + +#define IN_INTERRUPT in_interrupt() + +void gcm_init_p8(u128 htable[16], const u64 Xi[2]); +void gcm_gmult_p8(u64 Xi[2], const u128 htable[16]); +void gcm_ghash_p8(u64 Xi[2], const u128 htable[16], + const u8 *in, size_t len); + +struct p8_ghash_ctx { + /* key used by vector asm */ + u128 htable[16]; + /* key used by software fallback */ + be128 key; +}; + +struct p8_ghash_desc_ctx { + u64 shash[2]; + u8 buffer[GHASH_DIGEST_SIZE]; + int bytes; +}; + +static int p8_ghash_init(struct shash_desc *desc) +{ + struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc); + + dctx->bytes = 0; + memset(dctx->shash, 0, GHASH_DIGEST_SIZE); + return 0; +} + +static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key, + unsigned int keylen) +{ + struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(tfm)); + + if (keylen != GHASH_BLOCK_SIZE) + return -EINVAL; + + preempt_disable(); + pagefault_disable(); + enable_kernel_vsx(); + gcm_init_p8(ctx->htable, (const u64 *) key); + disable_kernel_vsx(); + pagefault_enable(); + preempt_enable(); + + memcpy(&ctx->key, key, GHASH_BLOCK_SIZE); + + return 0; +} + +static inline void __ghash_block(struct p8_ghash_ctx *ctx, + struct p8_ghash_desc_ctx *dctx) +{ + if (!IN_INTERRUPT) { + preempt_disable(); + pagefault_disable(); + enable_kernel_vsx(); + gcm_ghash_p8(dctx->shash, ctx->htable, + dctx->buffer, GHASH_DIGEST_SIZE); + disable_kernel_vsx(); + pagefault_enable(); + preempt_enable(); + } else { + crypto_xor((u8 *)dctx->shash, dctx->buffer, GHASH_BLOCK_SIZE); + gf128mul_lle((be128 *)dctx->shash, &ctx->key); + } +} + +static inline void __ghash_blocks(struct p8_ghash_ctx *ctx, + struct p8_ghash_desc_ctx *dctx, + const u8 *src, unsigned int srclen) +{ + if (!IN_INTERRUPT) { + preempt_disable(); + pagefault_disable(); + enable_kernel_vsx(); + gcm_ghash_p8(dctx->shash, ctx->htable, + src, srclen); + disable_kernel_vsx(); + pagefault_enable(); + preempt_enable(); + } else { + while (srclen >= GHASH_BLOCK_SIZE) { + crypto_xor((u8 *)dctx->shash, src, GHASH_BLOCK_SIZE); + gf128mul_lle((be128 *)dctx->shash, &ctx->key); + srclen -= GHASH_BLOCK_SIZE; + src += GHASH_BLOCK_SIZE; + } + } +} + +static int p8_ghash_update(struct shash_desc *desc, + const u8 *src, unsigned int srclen) +{ + unsigned int len; + struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm)); + struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc); + + if (dctx->bytes) { + if (dctx->bytes + srclen < GHASH_DIGEST_SIZE) { + memcpy(dctx->buffer + dctx->bytes, src, + srclen); + dctx->bytes += srclen; + return 0; + } + memcpy(dctx->buffer + dctx->bytes, src, + GHASH_DIGEST_SIZE - dctx->bytes); + + __ghash_block(ctx, dctx); + + src += GHASH_DIGEST_SIZE - dctx->bytes; + srclen -= GHASH_DIGEST_SIZE - dctx->bytes; + dctx->bytes = 0; + } + len = srclen & ~(GHASH_DIGEST_SIZE - 1); + if (len) { + __ghash_blocks(ctx, dctx, src, len); + src += len; + srclen -= len; + } + if (srclen) { + memcpy(dctx->buffer, src, srclen); + dctx->bytes = srclen; + } + return 0; +} + +static int p8_ghash_final(struct shash_desc *desc, u8 *out) +{ + int i; + struct p8_ghash_ctx *ctx = crypto_tfm_ctx(crypto_shash_tfm(desc->tfm)); + struct p8_ghash_desc_ctx *dctx = shash_desc_ctx(desc); + + if (dctx->bytes) { + for (i = dctx->bytes; i < GHASH_DIGEST_SIZE; i++) + dctx->buffer[i] = 0; + __ghash_block(ctx, dctx); + dctx->bytes = 0; + } + memcpy(out, dctx->shash, GHASH_DIGEST_SIZE); + return 0; +} + +struct shash_alg p8_ghash_alg = { + .digestsize = GHASH_DIGEST_SIZE, + .init = p8_ghash_init, + .update = p8_ghash_update, + .final = p8_ghash_final, + .setkey = p8_ghash_setkey, + .descsize = sizeof(struct p8_ghash_desc_ctx) + + sizeof(struct ghash_desc_ctx), + .base = { + .cra_name = "ghash", + .cra_driver_name = "p8_ghash", + .cra_priority = 1000, + .cra_blocksize = GHASH_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct p8_ghash_ctx), + .cra_module = THIS_MODULE, + }, +}; |