Re: [PATCH 1/2] crypto: inside-secure - Use defines instead of some constants (cosmetic)

[Antoine Tenart <antoine.tenart@bootlin.com>]

Hi Pascal,

On Tue, Jul 30, 2019 at 03:27:11PM +0200, Pascal van Leeuwen wrote:
> This patch replaces some hard constants regarding key, IV and nonce sizes
> with appropriate defines from the crypto header files.
> 
> Signed-off-by: Pascal van Leeuwen <pvanleeuwen@verimatrix.com>

Acked-by: Antoine Tenart <antoine.tenart@bootlin.com>

Thanks!
Antoine

> ---
>  drivers/crypto/inside-secure/safexcel_cipher.c | 35 ++++++++++++++------------
>  1 file changed, 19 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/crypto/inside-secure/safexcel_cipher.c b/drivers/crypto/inside-secure/safexcel_cipher.c
> index d65e5f7..a30fdd5 100644
> --- a/drivers/crypto/inside-secure/safexcel_cipher.c
> +++ b/drivers/crypto/inside-secure/safexcel_cipher.c
> @@ -12,6 +12,7 @@
>  #include <crypto/aead.h>
>  #include <crypto/aes.h>
>  #include <crypto/authenc.h>
> +#include <crypto/ctr.h>
>  #include <crypto/des.h>
>  #include <crypto/sha.h>
>  #include <crypto/skcipher.h>
> @@ -237,19 +238,21 @@ static int safexcel_aead_setkey(struct crypto_aead *ctfm, const u8 *key,
>  		goto badkey;
>  
>  	if (ctx->mode == CONTEXT_CONTROL_CRYPTO_MODE_CTR_LOAD) {
> -		/* 20 is minimum AES key: 16 bytes + 4 bytes nonce */
> -		if (keys.enckeylen < 20)
> +		/* Minimum keysize is minimum AES key size + nonce size */
> +		if (keys.enckeylen < (AES_MIN_KEY_SIZE +
> +				      CTR_RFC3686_NONCE_SIZE))
>  			goto badkey;
>  		/* last 4 bytes of key are the nonce! */
> -		ctx->nonce = *(u32 *)(keys.enckey + keys.enckeylen - 4);
> +		ctx->nonce = *(u32 *)(keys.enckey + keys.enckeylen -
> +				      CTR_RFC3686_NONCE_SIZE);
>  		/* exclude the nonce here */
> -		keys.enckeylen -= 4;
> +		keys.enckeylen -= CONTEXT_CONTROL_CRYPTO_MODE_CTR_LOAD;
>  	}
>  
>  	/* Encryption key */
>  	switch (ctx->alg) {
>  	case SAFEXCEL_3DES:
> -		if (keys.enckeylen != 24)
> +		if (keys.enckeylen != DES3_EDE_KEY_SIZE)
>  			goto badkey;
>  		flags = crypto_aead_get_flags(ctfm);
>  		err = __des3_verify_key(&flags, keys.enckey);
> @@ -1114,9 +1117,9 @@ static int safexcel_skcipher_aesctr_setkey(struct crypto_skcipher *ctfm,
>  	unsigned int keylen;
>  
>  	/* last 4 bytes of key are the nonce! */
> -	ctx->nonce = *(u32 *)(key + len - 4);
> +	ctx->nonce = *(u32 *)(key + len - CTR_RFC3686_NONCE_SIZE);
>  	/* exclude the nonce here */
> -	keylen = len - 4;
> +	keylen = len - CTR_RFC3686_NONCE_SIZE;
>  	ret = crypto_aes_expand_key(&aes, key, keylen);
>  	if (ret) {
>  		crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
> @@ -1157,10 +1160,10 @@ struct safexcel_alg_template safexcel_alg_ctr_aes = {
>  		.setkey = safexcel_skcipher_aesctr_setkey,
>  		.encrypt = safexcel_encrypt,
>  		.decrypt = safexcel_decrypt,
> -		/* Add 4 to include the 4 byte nonce! */
> -		.min_keysize = AES_MIN_KEY_SIZE + 4,
> -		.max_keysize = AES_MAX_KEY_SIZE + 4,
> -		.ivsize = 8,
> +		/* Add nonce size */
> +		.min_keysize = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
> +		.max_keysize = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
> +		.ivsize = CTR_RFC3686_IV_SIZE,
>  		.base = {
>  			.cra_name = "rfc3686(ctr(aes))",
>  			.cra_driver_name = "safexcel-ctr-aes",
> @@ -1620,7 +1623,7 @@ struct safexcel_alg_template safexcel_alg_authenc_hmac_sha1_ctr_aes = {
>  		.setkey = safexcel_aead_setkey,
>  		.encrypt = safexcel_aead_encrypt,
>  		.decrypt = safexcel_aead_decrypt,
> -		.ivsize = 8,
> +		.ivsize = CTR_RFC3686_IV_SIZE,
>  		.maxauthsize = SHA1_DIGEST_SIZE,
>  		.base = {
>  			.cra_name = "authenc(hmac(sha1),rfc3686(ctr(aes)))",
> @@ -1653,7 +1656,7 @@ struct safexcel_alg_template safexcel_alg_authenc_hmac_sha256_ctr_aes = {
>  		.setkey = safexcel_aead_setkey,
>  		.encrypt = safexcel_aead_encrypt,
>  		.decrypt = safexcel_aead_decrypt,
> -		.ivsize = 8,
> +		.ivsize = CTR_RFC3686_IV_SIZE,
>  		.maxauthsize = SHA256_DIGEST_SIZE,
>  		.base = {
>  			.cra_name = "authenc(hmac(sha256),rfc3686(ctr(aes)))",
> @@ -1686,7 +1689,7 @@ struct safexcel_alg_template safexcel_alg_authenc_hmac_sha224_ctr_aes = {
>  		.setkey = safexcel_aead_setkey,
>  		.encrypt = safexcel_aead_encrypt,
>  		.decrypt = safexcel_aead_decrypt,
> -		.ivsize = 8,
> +		.ivsize = CTR_RFC3686_IV_SIZE,
>  		.maxauthsize = SHA224_DIGEST_SIZE,
>  		.base = {
>  			.cra_name = "authenc(hmac(sha224),rfc3686(ctr(aes)))",
> @@ -1719,7 +1722,7 @@ struct safexcel_alg_template safexcel_alg_authenc_hmac_sha512_ctr_aes = {
>  		.setkey = safexcel_aead_setkey,
>  		.encrypt = safexcel_aead_encrypt,
>  		.decrypt = safexcel_aead_decrypt,
> -		.ivsize = 8,
> +		.ivsize = CTR_RFC3686_IV_SIZE,
>  		.maxauthsize = SHA512_DIGEST_SIZE,
>  		.base = {
>  			.cra_name = "authenc(hmac(sha512),rfc3686(ctr(aes)))",
> @@ -1752,7 +1755,7 @@ struct safexcel_alg_template safexcel_alg_authenc_hmac_sha384_ctr_aes = {
>  		.setkey = safexcel_aead_setkey,
>  		.encrypt = safexcel_aead_encrypt,
>  		.decrypt = safexcel_aead_decrypt,
> -		.ivsize = 8,
> +		.ivsize = CTR_RFC3686_IV_SIZE,
>  		.maxauthsize = SHA384_DIGEST_SIZE,
>  		.base = {
>  			.cra_name = "authenc(hmac(sha384),rfc3686(ctr(aes)))",
> -- 
> 1.8.3.1
> 

-- 
Antoine Ténart, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com