commit c22950c9d057be71938f7509280e72ce19c57cee
author Paul Elliott <paul.elliott@arm.com> Thu Jul 08 16:50:01 2021 +0100
committer Paul Elliott <paul.elliott@arm.com> Wed Jul 14 12:39:54 2021 +0100
tree 33231362f8c22c07934b335f0dd7c5ded1e49e1f
parent a02003babe4e5145d37f47f42a2565b33e8534ea

Change PSA Cipher macro safety to use block length

Although checking if the key was symmetric was correct, its easier to
read if we just check the block length is not zero before we use it in a
division.

Signed-off-by: Paul Elliott <paul.elliott@arm.com>

include/psa/crypto_sizes.h

diff --git a/include/psa/crypto_sizes.h b/include/psa/crypto_sizes.h
index 836f9ee..1f8b6c3 100644
--- a/include/psa/crypto_sizes.h
+++ b/include/psa/crypto_sizes.h
@@ -992,8 +992,7 @@
  */
 #define PSA_CIPHER_ENCRYPT_OUTPUT_SIZE(key_type, alg, input_length)             \
     (alg == PSA_ALG_CBC_PKCS7 ?                                                 \
-     (((key_type) & PSA_KEY_TYPE_CATEGORY_MASK)                                 \
-                                           == PSA_KEY_TYPE_CATEGORY_SYMMETRIC ? \
+     (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) != 0 ?                            \
      PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type),          \
                               (input_length) + 1) +                             \
      PSA_CIPHER_IV_LENGTH((key_type), (alg)) : 0) :                             \