From: Tobias Brunner <tobias@strongswan.org>
Date: Tue, 16 Nov 2021 13:33:09 +0000 (+0100)
Subject: openssl: Add helper to map ECDH groups to curve NIDs
X-Git-Tag: 5.9.5dr3~3^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=03520a0d54b3aefa5914dba349cc03432bc39d32;p=thirdparty%2Fstrongswan.git

openssl: Add helper to map ECDH groups to curve NIDs
---

diff --git a/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c b/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c
index de0d94a3e5..d591b05171 100644
--- a/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c
+++ b/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.c
@@ -328,49 +328,52 @@ METHOD(diffie_hellman_t, destroy, void,
 }
 
 /*
- * Described in header.
+ * Described in header
  */
-openssl_ec_diffie_hellman_t *openssl_ec_diffie_hellman_create(diffie_hellman_group_t group)
+int openssl_ecdh_group_to_nid(diffie_hellman_group_t group)
 {
-	private_openssl_ec_diffie_hellman_t *this;
-	EC_KEY *key = NULL;
-
 	switch (group)
 	{
 		case ECP_192_BIT:
-			key = EC_KEY_new_by_curve_name(NID_X9_62_prime192v1);
-			break;
+			return NID_X9_62_prime192v1;
 		case ECP_224_BIT:
-			key = EC_KEY_new_by_curve_name(NID_secp224r1);
-			break;
+			return NID_secp224r1;
 		case ECP_256_BIT:
-			key = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
-			break;
+			return NID_X9_62_prime256v1;
 		case ECP_384_BIT:
-			key = EC_KEY_new_by_curve_name(NID_secp384r1);
-			break;
+			return NID_secp384r1;
 		case ECP_521_BIT:
-			key = EC_KEY_new_by_curve_name(NID_secp521r1);
-			break;
+			return NID_secp521r1;
 /* added with 1.0.2 */
 #if OPENSSL_VERSION_NUMBER >= 0x10002000L
 		case ECP_224_BP:
-			key = EC_KEY_new_by_curve_name(NID_brainpoolP224r1);
-			break;
+			return NID_brainpoolP224r1;
 		case ECP_256_BP:
-			key = EC_KEY_new_by_curve_name(NID_brainpoolP256r1);
-			break;
+			return NID_brainpoolP256r1;
 		case ECP_384_BP:
-			key = EC_KEY_new_by_curve_name(NID_brainpoolP384r1);
-			break;
+			return NID_brainpoolP384r1;
 		case ECP_512_BP:
-			key = EC_KEY_new_by_curve_name(NID_brainpoolP512r1);
-			break;
+			return NID_brainpoolP512r1;
 #endif
 		default:
-			break;
+			return 0;
 	}
+}
 
+/*
+ * Described in header
+ */
+openssl_ec_diffie_hellman_t *openssl_ec_diffie_hellman_create(diffie_hellman_group_t group)
+{
+	private_openssl_ec_diffie_hellman_t *this;
+	EC_KEY *key = NULL;
+	int curve;
+
+	curve = openssl_ecdh_group_to_nid(group);
+	if (curve)
+	{
+		key = EC_KEY_new_by_curve_name(curve);
+	}
 	if (!key)
 	{
 		return NULL;
@@ -408,4 +411,5 @@ openssl_ec_diffie_hellman_t *openssl_ec_diffie_hellman_create(diffie_hellman_gro
 	}
 	return &this->public;
 }
+
 #endif /* OPENSSL_NO_EC */
diff --git a/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.h b/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.h
index 2f58c976d7..12563c6dae 100644
--- a/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.h
+++ b/src/libstrongswan/plugins/openssl/openssl_ec_diffie_hellman.h
@@ -44,5 +44,12 @@ struct openssl_ec_diffie_hellman_t {
  */
 openssl_ec_diffie_hellman_t *openssl_ec_diffie_hellman_create(diffie_hellman_group_t group);
 
-#endif /** OPENSSL_EC_DIFFIE_HELLMAN_H_ @}*/
+/**
+ * Map ECDH groups to OpenSSL NIDs for the ECC curve.
+ *
+ * @param group         ECDH group
+ * @return              NID for the curve
+ */
+int openssl_ecdh_group_to_nid(diffie_hellman_group_t group);
 
+#endif /** OPENSSL_EC_DIFFIE_HELLMAN_H_ @}*/