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

[Herbert Xu]

This patch forbids the use of 2-key 3DES (K1 == K3) in FIPS mode.
   
Signed-off-by: Herbert Xu <herb...@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,