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author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-07-24 11:28:13 +0100 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2017-08-04 09:27:21 +0800 |
commit | e211506979e205e5a00b0a9d321fb3cbb44ee9ea (patch) | |
tree | 234859ed43fc55e8f187d155ccdd4efd9da0dd97 /arch/arm64/crypto/aes-glue.c | |
parent | 5092fcf3490811a735ef44bd22d8b5ff1bd63926 (diff) | |
download | linux-e211506979e205e5a00b0a9d321fb3cbb44ee9ea.tar.gz linux-e211506979e205e5a00b0a9d321fb3cbb44ee9ea.tar.bz2 linux-e211506979e205e5a00b0a9d321fb3cbb44ee9ea.zip |
crypto: arm64/aes-blk - add a non-SIMD fallback for synchronous CTR
To accommodate systems that may disallow use of the NEON in kernel mode
in some circumstances, introduce a C fallback for synchronous AES in CTR
mode, and use it if may_use_simd() returns false.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'arch/arm64/crypto/aes-glue.c')
-rw-r--r-- | arch/arm64/crypto/aes-glue.c | 59 |
1 files changed, 44 insertions, 15 deletions
diff --git a/arch/arm64/crypto/aes-glue.c b/arch/arm64/crypto/aes-glue.c index 0da30e3b0e4b..998ba519a026 100644 --- a/arch/arm64/crypto/aes-glue.c +++ b/arch/arm64/crypto/aes-glue.c @@ -10,6 +10,7 @@ #include <asm/neon.h> #include <asm/hwcap.h> +#include <asm/simd.h> #include <crypto/aes.h> #include <crypto/internal/hash.h> #include <crypto/internal/simd.h> @@ -19,6 +20,7 @@ #include <crypto/xts.h> #include "aes-ce-setkey.h" +#include "aes-ctr-fallback.h" #ifdef USE_V8_CRYPTO_EXTENSIONS #define MODE "ce" @@ -249,6 +251,17 @@ static int ctr_encrypt(struct skcipher_request *req) return err; } +static int ctr_encrypt_sync(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm); + + if (!may_use_simd()) + return aes_ctr_encrypt_fallback(ctx, req); + + return ctr_encrypt(req); +} + static int xts_encrypt(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); @@ -355,8 +368,8 @@ static struct skcipher_alg aes_algs[] = { { .ivsize = AES_BLOCK_SIZE, .chunksize = AES_BLOCK_SIZE, .setkey = skcipher_aes_setkey, - .encrypt = ctr_encrypt, - .decrypt = ctr_encrypt, + .encrypt = ctr_encrypt_sync, + .decrypt = ctr_encrypt_sync, }, { .base = { .cra_name = "__xts(aes)", @@ -458,11 +471,35 @@ static int mac_init(struct shash_desc *desc) return 0; } +static void mac_do_update(struct crypto_aes_ctx *ctx, u8 const in[], int blocks, + u8 dg[], int enc_before, int enc_after) +{ + int rounds = 6 + ctx->key_length / 4; + + if (may_use_simd()) { + kernel_neon_begin(); + aes_mac_update(in, ctx->key_enc, rounds, blocks, dg, enc_before, + enc_after); + kernel_neon_end(); + } else { + if (enc_before) + __aes_arm64_encrypt(ctx->key_enc, dg, dg, rounds); + + while (blocks--) { + crypto_xor(dg, in, AES_BLOCK_SIZE); + in += AES_BLOCK_SIZE; + + if (blocks || enc_after) + __aes_arm64_encrypt(ctx->key_enc, dg, dg, + rounds); + } + } +} + static int mac_update(struct shash_desc *desc, const u8 *p, unsigned int len) { struct mac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); struct mac_desc_ctx *ctx = shash_desc_ctx(desc); - int rounds = 6 + tctx->key.key_length / 4; while (len > 0) { unsigned int l; @@ -474,10 +511,8 @@ static int mac_update(struct shash_desc *desc, const u8 *p, unsigned int len) len %= AES_BLOCK_SIZE; - kernel_neon_begin(); - aes_mac_update(p, tctx->key.key_enc, rounds, blocks, - ctx->dg, (ctx->len != 0), (len != 0)); - kernel_neon_end(); + mac_do_update(&tctx->key, p, blocks, ctx->dg, + (ctx->len != 0), (len != 0)); p += blocks * AES_BLOCK_SIZE; @@ -505,11 +540,8 @@ static int cbcmac_final(struct shash_desc *desc, u8 *out) { struct mac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); struct mac_desc_ctx *ctx = shash_desc_ctx(desc); - int rounds = 6 + tctx->key.key_length / 4; - kernel_neon_begin(); - aes_mac_update(NULL, tctx->key.key_enc, rounds, 0, ctx->dg, 1, 0); - kernel_neon_end(); + mac_do_update(&tctx->key, NULL, 0, ctx->dg, 1, 0); memcpy(out, ctx->dg, AES_BLOCK_SIZE); @@ -520,7 +552,6 @@ static int cmac_final(struct shash_desc *desc, u8 *out) { struct mac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); struct mac_desc_ctx *ctx = shash_desc_ctx(desc); - int rounds = 6 + tctx->key.key_length / 4; u8 *consts = tctx->consts; if (ctx->len != AES_BLOCK_SIZE) { @@ -528,9 +559,7 @@ static int cmac_final(struct shash_desc *desc, u8 *out) consts += AES_BLOCK_SIZE; } - kernel_neon_begin(); - aes_mac_update(consts, tctx->key.key_enc, rounds, 1, ctx->dg, 0, 1); - kernel_neon_end(); + mac_do_update(&tctx->key, consts, 1, ctx->dg, 0, 1); memcpy(out, ctx->dg, AES_BLOCK_SIZE); |