From c7da38a71cfbb5c0f20f84864a290b9450ad78e9 Mon Sep 17 00:00:00 2001 From: Pascal van Leeuwen Date: Fri, 30 Aug 2019 09:40:53 +0200 Subject: crypto: inside-secure - Add support for the AES-XTS algorithm This patch adds support for the AES-XTS skcipher algorithm. Signed-off-by: Pascal van Leeuwen Signed-off-by: Herbert Xu --- drivers/crypto/inside-secure/safexcel_cipher.c | 124 ++++++++++++++++++++++++- 1 file changed, 120 insertions(+), 4 deletions(-) (limited to 'drivers/crypto/inside-secure/safexcel_cipher.c') diff --git a/drivers/crypto/inside-secure/safexcel_cipher.c b/drivers/crypto/inside-secure/safexcel_cipher.c index ba40166897f9..05e34c62945c 100644 --- a/drivers/crypto/inside-secure/safexcel_cipher.c +++ b/drivers/crypto/inside-secure/safexcel_cipher.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -40,9 +41,9 @@ struct safexcel_cipher_ctx { enum safexcel_cipher_alg alg; bool aead; - __le32 key[8]; + __le32 key[16]; u32 nonce; - unsigned int key_len; + unsigned int key_len, xts; /* All the below is AEAD specific */ u32 hash_alg; @@ -351,7 +352,7 @@ static int safexcel_context_control(struct safexcel_cipher_ctx *ctx, } else if (ctx->alg == SAFEXCEL_3DES) { cdesc->control_data.control0 |= CONTEXT_CONTROL_CRYPTO_ALG_3DES; } else if (ctx->alg == SAFEXCEL_AES) { - switch (ctx->key_len) { + switch (ctx->key_len >> ctx->xts) { case AES_KEYSIZE_128: cdesc->control_data.control0 |= CONTEXT_CONTROL_CRYPTO_ALG_AES128; break; @@ -363,7 +364,7 @@ static int safexcel_context_control(struct safexcel_cipher_ctx *ctx, break; default: dev_err(priv->dev, "aes keysize not supported: %u\n", - ctx->key_len); + ctx->key_len >> ctx->xts); return -EINVAL; } } @@ -1747,3 +1748,118 @@ struct safexcel_alg_template safexcel_alg_authenc_hmac_sha384_ctr_aes = { }, }, }; + +static int safexcel_skcipher_aesxts_setkey(struct crypto_skcipher *ctfm, + const u8 *key, unsigned int len) +{ + struct crypto_tfm *tfm = crypto_skcipher_tfm(ctfm); + struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm); + struct safexcel_crypto_priv *priv = ctx->priv; + struct crypto_aes_ctx aes; + int ret, i; + unsigned int keylen; + + /* Check for illegal XTS keys */ + ret = xts_verify_key(ctfm, key, len); + if (ret) + return ret; + + /* Only half of the key data is cipher key */ + keylen = (len >> 1); + ret = aes_expandkey(&aes, key, keylen); + if (ret) { + crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_RES_BAD_KEY_LEN); + return ret; + } + + if (priv->flags & EIP197_TRC_CACHE && ctx->base.ctxr_dma) { + for (i = 0; i < keylen / sizeof(u32); i++) { + if (ctx->key[i] != cpu_to_le32(aes.key_enc[i])) { + ctx->base.needs_inv = true; + break; + } + } + } + + for (i = 0; i < keylen / sizeof(u32); i++) + ctx->key[i] = cpu_to_le32(aes.key_enc[i]); + + /* The other half is the tweak key */ + ret = aes_expandkey(&aes, (u8 *)(key + keylen), keylen); + if (ret) { + crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_RES_BAD_KEY_LEN); + return ret; + } + + if (priv->flags & EIP197_TRC_CACHE && ctx->base.ctxr_dma) { + for (i = 0; i < keylen / sizeof(u32); i++) { + if (ctx->key[i + keylen / sizeof(u32)] != + cpu_to_le32(aes.key_enc[i])) { + ctx->base.needs_inv = true; + break; + } + } + } + + for (i = 0; i < keylen / sizeof(u32); i++) + ctx->key[i + keylen / sizeof(u32)] = + cpu_to_le32(aes.key_enc[i]); + + ctx->key_len = keylen << 1; + + memzero_explicit(&aes, sizeof(aes)); + return 0; +} + +static int safexcel_skcipher_aes_xts_cra_init(struct crypto_tfm *tfm) +{ + struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm); + + safexcel_skcipher_cra_init(tfm); + ctx->alg = SAFEXCEL_AES; + ctx->xts = 1; + ctx->mode = CONTEXT_CONTROL_CRYPTO_MODE_XTS; + return 0; +} + +static int safexcel_encrypt_xts(struct skcipher_request *req) +{ + if (req->cryptlen < XTS_BLOCK_SIZE) + return -EINVAL; + return safexcel_queue_req(&req->base, skcipher_request_ctx(req), + SAFEXCEL_ENCRYPT); +} + +static int safexcel_decrypt_xts(struct skcipher_request *req) +{ + if (req->cryptlen < XTS_BLOCK_SIZE) + return -EINVAL; + return safexcel_queue_req(&req->base, skcipher_request_ctx(req), + SAFEXCEL_DECRYPT); +} + +struct safexcel_alg_template safexcel_alg_xts_aes = { + .type = SAFEXCEL_ALG_TYPE_SKCIPHER, + .alg.skcipher = { + .setkey = safexcel_skcipher_aesxts_setkey, + .encrypt = safexcel_encrypt_xts, + .decrypt = safexcel_decrypt_xts, + /* XTS actually uses 2 AES keys glued together */ + .min_keysize = AES_MIN_KEY_SIZE * 2, + .max_keysize = AES_MAX_KEY_SIZE * 2, + .ivsize = XTS_BLOCK_SIZE, + .base = { + .cra_name = "xts(aes)", + .cra_driver_name = "safexcel-xts-aes", + .cra_priority = 300, + .cra_flags = CRYPTO_ALG_ASYNC | + CRYPTO_ALG_KERN_DRIVER_ONLY, + .cra_blocksize = XTS_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct safexcel_cipher_ctx), + .cra_alignmask = 0, + .cra_init = safexcel_skcipher_aes_xts_cra_init, + .cra_exit = safexcel_skcipher_cra_exit, + .cra_module = THIS_MODULE, + }, + }, +}; -- cgit v1.2.3-59-g8ed1b