commit ffb5499988f7a2cd1d908a7c542e3daad22d72c7
author Dave Rodgman <dave.rodgman@arm.com> Tue Nov 22 16:40:58 2022 +0000
committer Dave Rodgman <dave.rodgman@arm.com> Tue Nov 22 17:32:44 2022 +0000
tree 4646e82ecbcad74ccf87d06db369614cfbaf2005
parent 8c0ff81ce713f84f6c70c92195d0a06a8bea442b

Use mbedtls_xor in CTR_DRBG

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>

library/ctr_drbg.c

diff --git a/library/ctr_drbg.c b/library/ctr_drbg.c
index 71c48af..f5c5e7b 100644
--- a/library/ctr_drbg.c
+++ b/library/ctr_drbg.c
@@ -174,8 +174,7 @@
 
         while( use_len > 0 )
         {
-            for( i = 0; i < MBEDTLS_CTR_DRBG_BLOCKSIZE; i++ )
-                chain[i] ^= p[i];
+            mbedtls_xor( chain, chain, p, MBEDTLS_CTR_DRBG_BLOCKSIZE );
             p += MBEDTLS_CTR_DRBG_BLOCKSIZE;
             use_len -= ( use_len >= MBEDTLS_CTR_DRBG_BLOCKSIZE ) ?
                        MBEDTLS_CTR_DRBG_BLOCKSIZE : use_len;