set6: challenge 45: completed

1 files changed, 15 insertions, 2 deletions

diff --git a/lib/lib6.c b/lib/lib6.c
index ef0db85..432c959 100644
--- a/lib/lib6.c
+++ b/lib/lib6.c
@@ -152,7 +152,7 @@ void dsa_sign(char *mess, struct dsa_public_params *pub_param, struct dsa_per_us
 	BN_zero(priv_param->r);
 	BN_zero(priv_param->s);
 
-	while(BN_is_zero(priv_param->r) || BN_is_zero(priv_param->s)) {
+	//while(BN_is_zero(priv_param->r) || BN_is_zero(priv_param->s)) {
 		if(BN_is_zero(k)) {
 			BN_pseudo_rand(k, pub_param->bits, -1, -1);
 			BN_mod(k, k, pub_param->q, ctx);
@@ -164,7 +164,7 @@ void dsa_sign(char *mess, struct dsa_public_params *pub_param, struct dsa_per_us
 		BN_mod_add(tmp, hash_bn, tmp, pub_param->q, ctx);
 		BN_mod_inverse(k_1, k, pub_param->q, ctx);
 		BN_mod_mul(priv_param->s, k_1, tmp, pub_param->q, ctx);
-	}
+	//}
 }
 
 
@@ -224,3 +224,16 @@ void dsa_recover_k_from_repeated_nonce(BIGNUM *mess1_hash, BIGNUM *mess2_hash,
 	printf("recoverd k is: \n");
 	BN_print(out, k);
 }
+
+void dsa_generate_magic_signature(struct dsa_public_params *pub, struct dsa_per_user_param
+		*priv, BIGNUM *mess_hash)
+{
+		BIGNUM *tmp = BN_new();
+
+		BN_mod_exp(tmp, priv->public, mess_hash, pub->p, ctx);
+		BN_mod(priv->r, tmp, pub->q, ctx);
+
+		BN_mod_inverse(tmp, mess_hash, pub->q, ctx);
+		BN_mod_mul(priv->s, priv->r, tmp, pub->q, ctx);
+
+}