commit 4353b698ed10851dcd97c1064119c6f65eedaa29
author Andrzej Kurek <andrzej.kurek@arm.com> Sun Jul 19 04:58:58 2020 -0400
committer Andrzej Kurek <andrzej.kurek@arm.com> Sun Jul 19 09:00:18 2020 -0400
tree c9db375bd8b7d242556c42d68b1035a6b3aa7ca8
parent f6265441b04dacb7c88e1a8133a13eca9ea245bc

hmac_drbg: make no reseeding behaviour explicit

Add a flag to the hmac_drbg context that will signal that reseeding is not required.
Change tests and one ecdsa call to not use reseeding, as was the previous case.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>

library/ecdsa.c

diff --git a/library/ecdsa.c b/library/ecdsa.c
index 6cfaa08..a0b890d 100644
--- a/library/ecdsa.c
+++ b/library/ecdsa.c
@@ -482,6 +482,7 @@
         mbedtls_hmac_drbg_context rng_ctx_blind;
 
         mbedtls_hmac_drbg_init( &rng_ctx_blind );
+        mbedtls_hmac_drbg_set_reseeding( &rng_ctx_blind, MBEDTLS_HMAC_DRBG_NO_RESEED );
         p_rng_blind_det = &rng_ctx_blind;
 
         mbedtls_hmac_drbg_seed_buf( p_rng_blind_det, md_info,
@@ -509,6 +510,7 @@
          * a valid ECDSA signature.
          */
         p_rng_blind_det = p_rng;
+        mbedtls_hmac_drbg_set_reseeding( p_rng_blind_det, MBEDTLS_HMAC_DRBG_NO_RESEED );
 #endif /* MBEDTLS_ECP_RESTARTABLE */
 
         /*