Support signing of RADIUS response messages

src/libcharon/plugins/eap_radius/radius_message.c

@@ -279,14 +279,21 @@ METHOD(radius_message_t, add, void,
 }
 
 METHOD(radius_message_t, sign, void,
-	private_radius_message_t *this, rng_t *rng, signer_t *signer,
+	private_radius_message_t *this, u_int8_t *req_auth, chunk_t secret,
-	hasher_t *hasher, chunk_t secret)
+	hasher_t *hasher, signer_t *signer, rng_t *rng)
 {
-	if (this->msg->code == RMC_ACCOUNTING_REQUEST)
+	if (rng == NULL)
 	{
 		chunk_t msg;
 
-		memset(this->msg->authenticator, 0, sizeof(this->msg->authenticator));
+		if (req_auth)
+		{
+			memcpy(this->msg->authenticator, req_auth, HASH_SIZE_MD5);
+		}
+		else
+		{
+			memset(this->msg->authenticator, 0, sizeof(this->msg->authenticator));
+		}
 		msg = chunk_create((u_char*)this->msg, ntohs(this->msg->length));
 		hasher->get_hash(hasher, msg, NULL);
 		hasher->get_hash(hasher, secret, this->msg->authenticator);

src/libcharon/plugins/eap_radius/radius_message.h

@@ -242,21 +242,22 @@ struct radius_message_t {
 	/**
 	 * Calculate and add the Message-Authenticator attribute to the message.
 	 *
-	 * @param rng			RNG to create Request-Authenticator
+	 * @param req_auth		16 byte Authenticator of request, or NULL
+	 * @param secret		shared RADIUS secret
 	 * @param signer		HMAC-MD5 signer with secret set
 	 * @param hasher		MD5 hasher
-	 * @param secret		shared RADIUS secret
+	 * @param rng			RNG to create Message-Authenticator, NULL to omit
 	 */
-	void (*sign)(radius_message_t *this, rng_t *rng, signer_t *signer,
+	void (*sign)(radius_message_t *this, u_int8_t *req_auth, chunk_t secret,
-				 hasher_t *hasher, chunk_t secret);
+				 hasher_t *hasher, signer_t *signer, rng_t *rng);
 
 	/**
 	 * Verify the integrity of a received RADIUS message.
 	 *
 	 * @param req_auth		16 byte Authenticator of request, or NULL
 	 * @param secret		shared RADIUS secret
-	 * @param hasher		hasher to verify Response-Authenticator
+	 * @param signer		HMAC-MD5 signer with secret set
-	 * @param signer		signer to verify Message-Authenticator attribute
+	 * @param hasher		MD5 hasher
 	 */
 	bool (*verify)(radius_message_t *this, u_int8_t *req_auth, chunk_t secret,
 				   hasher_t *hasher, signer_t *signer);

src/libcharon/plugins/eap_radius/radius_socket.c

@@ -140,11 +140,7 @@ METHOD(radius_socket_t, request, radius_message_t*,
 	chunk_t data;
 	int i, *fd;
 	u_int16_t port;
-
+	rng_t *rng = NULL;
-	/* set Message Identifier */
-	request->set_identifier(request, this->identifier++);
-	/* sign the request */
-	request->sign(request, this->rng, this->signer, this->hasher, this->secret);
 
 	if (request->get_code(request) == RMC_ACCOUNTING_REQUEST)
 	{
@@ -155,7 +151,14 @@ METHOD(radius_socket_t, request, radius_message_t*,
 	{
 		fd = &this->auth_fd;
 		port = this->auth_port;
+		rng = this->rng;
 	}
+
+	/* set Message Identifier */
+	request->set_identifier(request, this->identifier++);
+	/* sign the request */
+	request->sign(request, NULL, this->secret, this->hasher, this->signer, rng);
+
 	if (!check_connection(this, fd, port))
 	{
 		return NULL;