crypto: inside-secure - Added support for the AES-CMAC ahash

This patch adds support for the AES-CMAC authentication algorithm.

Signed-off-by: Pascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/inside-secure/safexcel.c b/drivers/crypto/inside-secure/safexcel.c
index 593ae66..d0f49a5 100644 (file)
--- a/drivers/crypto/inside-secure/safexcel.c
+++ b/drivers/crypto/inside-secure/safexcel.c
@@ -1172,6 +1172,7 @@ static struct safexcel_alg_template *safexcel_algs[] = {
        &safexcel_alg_crc32,
        &safexcel_alg_cbcmac,
        &safexcel_alg_xcbcmac,
+       &safexcel_alg_cmac,
 };
 
 static int safexcel_register_algorithms(struct safexcel_crypto_priv *priv)

diff --git a/drivers/crypto/inside-secure/safexcel.h b/drivers/crypto/inside-secure/safexcel.h
index 6f08b13..6ddc6d1 100644 (file)
--- a/drivers/crypto/inside-secure/safexcel.h
+++ b/drivers/crypto/inside-secure/safexcel.h
@@ -857,5 +857,6 @@ extern struct safexcel_alg_template safexcel_alg_ccm;
 extern struct safexcel_alg_template safexcel_alg_crc32;
 extern struct safexcel_alg_template safexcel_alg_cbcmac;
 extern struct safexcel_alg_template safexcel_alg_xcbcmac;
+extern struct safexcel_alg_template safexcel_alg_cmac;
 
 #endif

diff --git a/drivers/crypto/inside-secure/safexcel_hash.c b/drivers/crypto/inside-secure/safexcel_hash.c
index 6576430..0224779 100644 (file)
--- a/drivers/crypto/inside-secure/safexcel_hash.c
+++ b/drivers/crypto/inside-secure/safexcel_hash.c
@@ -2122,3 +2122,102 @@ struct safexcel_alg_template safexcel_alg_xcbcmac = {
                },
        },
 };
+
+static int safexcel_cmac_setkey(struct crypto_ahash *tfm, const u8 *key,
+                               unsigned int len)
+{
+       struct safexcel_ahash_ctx *ctx = crypto_tfm_ctx(crypto_ahash_tfm(tfm));
+       struct crypto_aes_ctx aes;
+       __be64 consts[4];
+       u64 _const[2];
+       u8 msb_mask, gfmask;
+       int ret, i;
+
+       ret = aes_expandkey(&aes, key, len);
+       if (ret) {
+               crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+               return ret;
+       }
+
+       for (i = 0; i < len / sizeof(u32); i++)
+               ctx->ipad[i + 8] = cpu_to_be32(aes.key_enc[i]);
+
+       /* precompute the CMAC key material */
+       crypto_cipher_clear_flags(ctx->kaes, CRYPTO_TFM_REQ_MASK);
+       crypto_cipher_set_flags(ctx->kaes, crypto_ahash_get_flags(tfm) &
+                               CRYPTO_TFM_REQ_MASK);
+       ret = crypto_cipher_setkey(ctx->kaes, key, len);
+       crypto_ahash_set_flags(tfm, crypto_cipher_get_flags(ctx->kaes) &
+                              CRYPTO_TFM_RES_MASK);
+       if (ret)
+               return ret;
+
+       /* code below borrowed from crypto/cmac.c */
+       /* encrypt the zero block */
+       memset(consts, 0, AES_BLOCK_SIZE);
+       crypto_cipher_encrypt_one(ctx->kaes, (u8 *)consts, (u8 *)consts);
+
+       gfmask = 0x87;
+       _const[0] = be64_to_cpu(consts[1]);
+       _const[1] = be64_to_cpu(consts[0]);
+
+       /* gf(2^128) multiply zero-ciphertext with u and u^2 */
+       for (i = 0; i < 4; i += 2) {
+               msb_mask = ((s64)_const[1] >> 63) & gfmask;
+               _const[1] = (_const[1] << 1) | (_const[0] >> 63);
+               _const[0] = (_const[0] << 1) ^ msb_mask;
+
+               consts[i + 0] = cpu_to_be64(_const[1]);
+               consts[i + 1] = cpu_to_be64(_const[0]);
+       }
+       /* end of code borrowed from crypto/cmac.c */
+
+       for (i = 0; i < 2 * AES_BLOCK_SIZE / sizeof(u32); i++)
+               ctx->ipad[i] = cpu_to_be32(((u32 *)consts)[i]);
+
+       if (len == AES_KEYSIZE_192) {
+               ctx->alg    = CONTEXT_CONTROL_CRYPTO_ALG_XCBC192;
+               ctx->key_sz = AES_MAX_KEY_SIZE + 2 * AES_BLOCK_SIZE;
+       } else if (len == AES_KEYSIZE_256) {
+               ctx->alg    = CONTEXT_CONTROL_CRYPTO_ALG_XCBC256;
+               ctx->key_sz = AES_MAX_KEY_SIZE + 2 * AES_BLOCK_SIZE;
+       } else {
+               ctx->alg    = CONTEXT_CONTROL_CRYPTO_ALG_XCBC128;
+               ctx->key_sz = AES_MIN_KEY_SIZE + 2 * AES_BLOCK_SIZE;
+       }
+       ctx->cbcmac = false;
+
+       memzero_explicit(&aes, sizeof(aes));
+       return 0;
+}
+
+struct safexcel_alg_template safexcel_alg_cmac = {
+       .type = SAFEXCEL_ALG_TYPE_AHASH,
+       .algo_mask = 0,
+       .alg.ahash = {
+               .init = safexcel_cbcmac_init,
+               .update = safexcel_ahash_update,
+               .final = safexcel_ahash_final,
+               .finup = safexcel_ahash_finup,
+               .digest = safexcel_cbcmac_digest,
+               .setkey = safexcel_cmac_setkey,
+               .export = safexcel_ahash_export,
+               .import = safexcel_ahash_import,
+               .halg = {
+                       .digestsize = AES_BLOCK_SIZE,
+                       .statesize = sizeof(struct safexcel_ahash_export_state),
+                       .base = {
+                               .cra_name = "cmac(aes)",
+                               .cra_driver_name = "safexcel-cmac-aes",
+                               .cra_priority = SAFEXCEL_CRA_PRIORITY,
+                               .cra_flags = CRYPTO_ALG_ASYNC |
+                                            CRYPTO_ALG_KERN_DRIVER_ONLY,
+                               .cra_blocksize = AES_BLOCK_SIZE,
+                               .cra_ctxsize = sizeof(struct safexcel_ahash_ctx),
+                               .cra_init = safexcel_xcbcmac_cra_init,
+                               .cra_exit = safexcel_xcbcmac_cra_exit,
+                               .cra_module = THIS_MODULE,
+                       },
+               },
+       },
+};