length of secret exponent is needed only when we create one

diff --git a/crypto/dh/dh_key.c b/crypto/dh/dh_key.c
index e097683f0753f2610d28d40ff91fb3d1af74e257..17b267feb4ae900bed7c811fdebcf30098a993ef 100644 (file)
--- a/crypto/dh/dh_key.c
+++ b/crypto/dh/dh_key.c
@@ -132,10 +132,9 @@ static int generate_key(DH *dh)
                }
        mont=(BN_MONT_CTX *)dh->method_mont_p;
 
-       l = dh->length ? dh->length : BN_num_bits(dh->p)-1; /* secret exponent length */
-
        if (generate_new_key)
                {
+               l = dh->length ? dh->length : BN_num_bits(dh->p)-1; /* secret exponent length */
                if (!BN_rand(priv_key, l, 0, 0)) goto err;
                }
        if (!dh->meth->bn_mod_exp(dh, pub_key,dh->g,priv_key,dh->p,&ctx,mont)) goto err;