commit e0e9c7c417e694b30870a9068769f1ca933f7d42
author Gilles Peskine <Gilles.Peskine@arm.com> Wed Oct 17 18:28:05 2018 +0200
committer Gilles Peskine <Gilles.Peskine@arm.com> Wed Oct 17 18:30:47 2018 +0200
tree 0fd67d9aed33aab7969754390291754b15c47416
parent 57fbdb19397ec8b45a002252f5f187d7f6c76a19

New macro PSA_ALG_FULL_LENGTH_MAC

Provide a documented way of constructing the full-length MAC algorithm
from a truncated version.

library/psa_crypto.c

diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index ab9ec72..6b01c13 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -1527,7 +1527,7 @@
     psa_key_usage_t usage =
         is_sign ? PSA_KEY_USAGE_SIGN : PSA_KEY_USAGE_VERIFY;
     unsigned char truncated = PSA_MAC_TRUNCATED_LENGTH( alg );
-    psa_algorithm_t full_length_alg = alg & ~PSA_ALG_MAC_TRUNCATION_MASK;
+    psa_algorithm_t full_length_alg = PSA_ALG_FULL_LENGTH_MAC( alg );
 
     status = psa_mac_init( operation, full_length_alg );
     if( status != PSA_SUCCESS )