[PATCH 21/24] crypto: stm32 - Forbid 2-key 3DES in FIPS mode

[Herbert Xu <herbert@gondor.apana.org.au>]

This patch forbids the use of 2-key 3DES (K1 == K3) in FIPS mode.
   
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---

 drivers/crypto/stm32/stm32-cryp.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c
index 23b0b7bd64c7..5785f3e235ce 100644
--- a/drivers/crypto/stm32/stm32-cryp.c
+++ b/drivers/crypto/stm32/stm32-cryp.c
@@ -762,10 +762,17 @@ static int stm32_cryp_des_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
 static int stm32_cryp_tdes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
 				  unsigned int keylen)
 {
-	if (keylen != (3 * DES_KEY_SIZE))
-		return -EINVAL;
-	else
-		return stm32_cryp_setkey(tfm, key, keylen);
+	u32 flags;
+	int err;
+
+	flags = crypto_ablkcipher_get_flags(tfm);
+	err = __des3_verify_key(&flags, key);
+	if (unlikely(err)) {
+		crypto_ablkcipher_set_flags(tfm, flags);
+		return err;
+	}
+
+	return stm32_cryp_setkey(tfm, key, keylen);
 }
 
 static int stm32_cryp_aes_aead_setkey(struct crypto_aead *tfm, const u8 *key,