[PATCH 18/24] crypto: picoxcell - Forbid 2-key 3DES in FIPS mode

Herbert Xu
2019-04-11T08:51:18Z

It also removes an unnecessary key length checks that are already
performed by the crypto API.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---

drivers/crypto/picoxcell_crypto.c | 33 ++++++++++++++++++++++++++-------
1 file changed, 26 insertions(+), 7 deletions(-)

diff --git a/drivers/crypto/picoxcell_crypto.c b/drivers/crypto/picoxcell_crypto.c
index 1b3acdeffede..975582b82a23 100644
--- a/drivers/crypto/picoxcell_crypto.c
+++ b/drivers/crypto/picoxcell_crypto.c
@@ -753,11 +753,6 @@ static int spacc_des_setkey(struct crypto_ablkcipher *cipher, const u8 *key,
struct spacc_ablk_ctx *ctx = crypto_tfm_ctx(tfm);
u32 tmp[DES_EXPKEY_WORDS];

- if (len > DES3_EDE_KEY_SIZE) {
- crypto_ablkcipher_set_flags(cipher, CRYPTO_TFM_RES_BAD_KEY_LEN);
- return -EINVAL;
- }
-
if (unlikely(!des_ekey(tmp, key)) &&
(crypto_ablkcipher_get_flags(cipher) &
CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)) {
@@ -772,6 +767,30 @@ static int spacc_des_setkey(struct crypto_ablkcipher *cipher, const u8 *key,
}

/*
+ * Set the 3DES key for a block cipher transform. This also performs weak key
+ * checking if the transform has requested it.
+ */
+static int spacc_des3_setkey(struct crypto_ablkcipher *cipher, const u8 *key,
+ unsigned int len)
+{
+ struct spacc_ablk_ctx *ctx = crypto_ablkcipher_ctx(cipher);
+ u32 flags;
+ int err;
+
+ flags = crypto_ablkcipher_get_flags(cipher);
+ err = __des3_verify_key(&flags, key);
+ if (unlikely(err)) {
+ crypto_ablkcipher_set_flags(cipher, flags);
+ return err;
+ }
+
+ memcpy(ctx->key, key, len);
+ ctx->key_len = len;
+
+ return 0;
+}
+
+/*
* Set the key for an AES block cipher. Some key lengths are not supported in
* hardware so this must also check whether a fallback is needed.
*/
@@ -1353,7 +1372,7 @@ static struct spacc_alg ipsec_engine_algs[] = {
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_ablkcipher = {
- .setkey = spacc_des_setkey,
+ .setkey = spacc_des3_setkey,
.encrypt = spacc_ablk_encrypt,
.decrypt = spacc_ablk_decrypt,
.min_keysize = DES3_EDE_KEY_SIZE,
@@ -1380,7 +1399,7 @@ static struct spacc_alg ipsec_engine_algs[] = {
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
.cra_ablkcipher = {
- .setkey = spacc_des_setkey,
+ .setkey = spacc_des3_setkey,
.encrypt = spacc_ablk_encrypt,
.decrypt = spacc_ablk_decrypt,
.min_keysize = DES3_EDE_KEY_SIZE,