Store DH generator in a chunk, hide non-public data in a private struct

src/libstrongswan/plugins/gcrypt/gcrypt_dh.c

@@ -203,15 +203,24 @@ gcrypt_dh_t *gcrypt_dh_create(diffie_hellman_group_t group)
 	this->public.dh.destroy = (void (*)(diffie_hellman_t *)) destroy;
 
 	this->group = group;
-	this->p_len = params->prime_len;
+	this->p_len = params->prime.len;
 	err = gcry_mpi_scan(&this->p, GCRYMPI_FMT_USG,
-						params->prime, params->prime_len, NULL);
+						params->prime.ptr, params->prime.len, NULL);
 	if (err)
 	{
 		DBG1(DBG_LIB, "importing mpi modulus failed: %s", gpg_strerror(err));
 		free(this);
 		return NULL;
 	}
+	err = gcry_mpi_scan(&this->g, GCRYMPI_FMT_USG,
+						params->generator.ptr, params->generator.len, NULL);
+	if (err)
+	{
+		DBG1(DBG_LIB, "importing mpi generator failed: %s", gpg_strerror(err));
+		gcry_mpi_release(this->p);
+		free(this);
+		return NULL;
+	}
 
 	rng = lib->crypto->create_rng(lib->crypto, RNG_STRONG);
 	if (rng)
@@ -225,6 +234,7 @@ gcrypt_dh_t *gcrypt_dh_create(diffie_hellman_group_t group)
 		{
 			DBG1(DBG_LIB, "importing mpi xa failed: %s", gpg_strerror(err));
 			gcry_mpi_release(this->p);
+			gcry_mpi_release(this->g);
 			free(this);
 			return NULL;
 		}
@@ -240,7 +250,6 @@ gcrypt_dh_t *gcrypt_dh_create(diffie_hellman_group_t group)
 		gcry_mpi_clear_bit(this->xa, params->exp_len * 8 - 1);
 	}
 
-	this->g = gcry_mpi_set_ui(NULL, params->generator);
 	this->ya = gcry_mpi_new(this->p_len * 8);
 	this->yb = NULL;
 	this->zz = NULL;

src/libstrongswan/plugins/gmp/gmp_diffie_hellman.c

@@ -194,11 +194,19 @@ static void destroy(private_gmp_diffie_hellman_t *this)
  */
 gmp_diffie_hellman_t *gmp_diffie_hellman_create(diffie_hellman_group_t group)
 {
-	private_gmp_diffie_hellman_t *this = malloc_thing(private_gmp_diffie_hellman_t);
+	private_gmp_diffie_hellman_t *this;
 	diffie_hellman_params_t *params;
 	rng_t *rng;
 	chunk_t random;
 
+	params = diffie_hellman_get_params(group);
+	if (!params)
+	{
+		return NULL;
+	}
+
+	this = malloc_thing(private_gmp_diffie_hellman_t);
+
 	/* public functions */
 	this->public.dh.get_shared_secret = (status_t (*)(diffie_hellman_t *, chunk_t *)) get_shared_secret;
 	this->public.dh.set_other_public_value = (void (*)(diffie_hellman_t *, chunk_t )) set_other_public_value;
@@ -216,16 +224,9 @@ gmp_diffie_hellman_t *gmp_diffie_hellman_create(diffie_hellman_group_t group)
 	mpz_init(this->g);
 
 	this->computed = FALSE;
-
-	params = diffie_hellman_get_params(this->group);
-	if (!params)
-	{
-		destroy(this);
-		return NULL;
-	}
-	mpz_import(this->p, params->prime_len, 1, 1, 1, 0, params->prime);
-	this->p_len = params->prime_len;
-	mpz_set_ui(this->g, params->generator);
+	this->p_len = params->prime.len;
+	mpz_import(this->p, params->prime.len, 1, 1, 1, 0, params->prime.ptr);
+	mpz_import(this->g, params->generator.len, 1, 1, 1, 0, params->generator.ptr);
 
 	rng = lib->crypto->create_rng(lib->crypto, RNG_STRONG);
 	if (!rng)

src/libstrongswan/plugins/openssl/openssl_diffie_hellman.c

@@ -128,10 +128,9 @@ static status_t set_modulus(private_openssl_diffie_hellman_t *this)
 	{
 		return NOT_FOUND;
 	}
-	this->dh->p = BN_bin2bn(params->prime, params->prime_len, NULL);
-	this->dh->g = BN_new();
-	BN_set_word(this->dh->g, params->generator);
-	if (params->exp_len != params->prime_len)
+	this->dh->p = BN_bin2bn(params->prime.ptr, params->prime.len, NULL);
+	this->dh->g = BN_bin2bn(params->generator.ptr, params->generator.len, NULL);
+	if (params->exp_len != params->prime.len)
 	{
 		this->dh->length = params->exp_len * 8;
 	}