Updated openssl plugin to the new builder API

9 files changed, 255 insertions, 382 deletions

diff --git a/src/libstrongswan/plugins/openssl/openssl_ec_private_key.c b/src/libstrongswan/plugins/openssl/openssl_ec_private_key.c
index c6e651e9b..853314069 100644
--- a/src/libstrongswan/plugins/openssl/openssl_ec_private_key.c
+++ b/src/libstrongswan/plugins/openssl/openssl_ec_private_key.c
@@ -295,12 +295,33 @@ static private_openssl_ec_private_key_t *create_empty(void)
 }
 
 /**
- * Generate an ECDSA key of specified key size
+ * See header.
  */
-static openssl_ec_private_key_t *generate(size_t key_size)
+openssl_ec_private_key_t *openssl_ec_private_key_gen(key_type_t type,
+													 va_list args)
 {
-	private_openssl_ec_private_key_t *this = create_empty();
+	private_openssl_ec_private_key_t *this;
+	u_int key_size = 0;
 
+	while (TRUE)
+	{
+		switch (va_arg(args, builder_part_t))
+		{
+			case BUILD_KEY_SIZE:
+				key_size = va_arg(args, u_int);
+				continue;
+			case BUILD_END:
+				break;
+			default:
+				return NULL;
+		}
+		break;
+	}
+	if (!key_size)
+	{
+		return NULL;
+	}
+	this = create_empty();
 	switch (key_size)
 	{
 		case 256:
@@ -330,104 +351,41 @@ static openssl_ec_private_key_t *generate(size_t key_size)
 }
 
 /**
- * load private key from an ASN1 encoded blob
+ * See header.
  */
-static openssl_ec_private_key_t *load(chunk_t blob)
+openssl_ec_private_key_t *openssl_ec_private_key_load(key_type_t type,
+													  va_list args)
 {
-	private_openssl_ec_private_key_t *this = create_empty();
-
-	this->ec = d2i_ECPrivateKey(NULL, (const u_char**)&blob.ptr, blob.len);
+	private_openssl_ec_private_key_t *this;
+	chunk_t blob = chunk_empty;
 
-	if (!this->ec)
-	{
-		destroy(this);
-		return NULL;
-	}
-	if (!EC_KEY_check_key(this->ec))
+	while (TRUE)
 	{
-		destroy(this);
-		return NULL;
-	}
-	return &this->public;
-}
-
-typedef struct private_builder_t private_builder_t;
-
-/**
- * Builder implementation for key loading/generation
- */
-struct private_builder_t {
-	/** implements the builder interface */
-	builder_t public;
-	/** loaded/generated private key */
-	openssl_ec_private_key_t *key;
-};
-
-/**
- * Implementation of builder_t.build
- */
-static openssl_ec_private_key_t *build(private_builder_t *this)
-{
-	openssl_ec_private_key_t *key = this->key;
-
-	free(this);
-	return key;
-}
-
-/**
- * Implementation of builder_t.add
- */
-static void add(private_builder_t *this, builder_part_t part, ...)
-{
-	if (!this->key)
-	{
-		va_list args;
-
-		switch (part)
+		switch (va_arg(args, builder_part_t))
 		{
-			case BUILD_KEY_SIZE:
-			{
-				va_start(args, part);
-				this->key = generate(va_arg(args, u_int));
-				va_end(args);
-				return;
-			}
 			case BUILD_BLOB_ASN1_DER:
-			{
-				va_start(args, part);
-				this->key = load(va_arg(args, chunk_t));
-				va_end(args);
-				return;
-			}
-			default:
+				blob = va_arg(args, chunk_t);
+				continue;
+			case BUILD_END:
 				break;
+			default:
+				return NULL;
 		}
+		break;
 	}
-	if (this->key)
+
+	this = create_empty();
+	this->ec = d2i_ECPrivateKey(NULL, (const u_char**)&blob.ptr, blob.len);
+	if (!this->ec)
 	{
-		destroy((private_openssl_ec_private_key_t*)this->key);
+		destroy(this);
+		return NULL;
 	}
-	builder_cancel(&this->public);
-}
-
-/**
- * Builder construction function
- */
-builder_t *openssl_ec_private_key_builder(key_type_t type)
-{
-	private_builder_t *this;
-
-	if (type != KEY_ECDSA)
+	if (!EC_KEY_check_key(this->ec))
 	{
+		destroy(this);
 		return NULL;
 	}
-
-	this = malloc_thing(private_builder_t);
-
-	this->key = NULL;
-	this->public.add = (void(*)(builder_t *this, builder_part_t part, ...))add;
-	this->public.build = (void*(*)(builder_t *this))build;
-
 	return &this->public;
 }
 
diff --git a/src/libstrongswan/plugins/openssl/openssl_ec_private_key.h b/src/libstrongswan/plugins/openssl/openssl_ec_private_key.h
index 6a6f7c867..720c63f90 100644
--- a/src/libstrongswan/plugins/openssl/openssl_ec_private_key.h
+++ b/src/libstrongswan/plugins/openssl/openssl_ec_private_key.h
@@ -21,6 +21,7 @@
 #ifndef OPENSSL_EC_PRIVATE_KEY_H_
 #define OPENSSL_EC_PRIVATE_KEY_H_
 
+#include <credentials/builder.h>
 #include <credentials/keys/private_key.h>
 
 typedef struct openssl_ec_private_key_t openssl_ec_private_key_t;
@@ -37,11 +38,27 @@ struct openssl_ec_private_key_t {
 };
 
 /**
- * Create the builder for a private key.
+ * Generate a ECDSA private key using OpenSSL.
+ *
+ * Accepts the BUILD_KEY_SIZE argument.
+ *
+ * @param type		type of the key, must be KEY_ECDSA
+ * @param args		builder_part_t argument list
+ * @return 			generated key, NULL on failure
+ */
+openssl_ec_private_key_t *openssl_ec_private_key_gen(key_type_t type,
+													 va_list args);
+
+/**
+ * Load a ECDSA private key using OpenSSL.
+ *
+ * Accepts a BUILD_BLOB_ASN1_DER argument.
  *
  * @param type		type of the key, must be KEY_ECDSA
- * @return 			builder instance
+ * @param args		builder_part_t argument list
+ * @return 			loaded key, NULL on failure
  */
-builder_t *openssl_ec_private_key_builder(key_type_t type);
+openssl_ec_private_key_t *openssl_ec_private_key_load(key_type_t type,
+													  va_list args);
 
 #endif /** OPENSSL_EC_PRIVATE_KEY_H_ @}*/
diff --git a/src/libstrongswan/plugins/openssl/openssl_ec_public_key.c b/src/libstrongswan/plugins/openssl/openssl_ec_public_key.c
index b0b2c9b50..f553c263a 100644
--- a/src/libstrongswan/plugins/openssl/openssl_ec_public_key.c
+++ b/src/libstrongswan/plugins/openssl/openssl_ec_public_key.c
@@ -308,93 +308,40 @@ static private_openssl_ec_public_key_t *create_empty()
 }
 
 /**
- * Load a public key from an ASN1 encoded blob
+ * See header.
  */
-static openssl_ec_public_key_t *load(chunk_t blob)
+openssl_ec_public_key_t *openssl_ec_public_key_load(key_type_t type,
+													va_list args)
 {
-	private_openssl_ec_public_key_t *this = create_empty();
-	u_char *p = blob.ptr;
+	private_openssl_ec_public_key_t *this;
+	chunk_t blob = chunk_empty;
 
-	this->ec = d2i_EC_PUBKEY(NULL, (const u_char**)&p, blob.len);
-
-	if (!this->ec)
+	if (type != KEY_ECDSA)
 	{
-		destroy(this);
 		return NULL;
 	}
-	return &this->public;
-}
-
-typedef struct private_builder_t private_builder_t;
 
-/**
- * Builder implementation for key loading
- */
-struct private_builder_t {
-	/** implements the builder interface */
-	builder_t public;
-	/** loaded public key */
-	openssl_ec_public_key_t *key;
-};
-
-/**
- * Implementation of builder_t.build
- */
-static openssl_ec_public_key_t *build(private_builder_t *this)
-{
-	openssl_ec_public_key_t *key = this->key;
-
-	free(this);
-	return key;
-}
-
-/**
- * Implementation of builder_t.add
- */
-static void add(private_builder_t *this, builder_part_t part, ...)
-{
-	if (!this->key)
+	while (TRUE)
 	{
-		va_list args;
-
-		switch (part)
+		switch (va_arg(args, builder_part_t))
 		{
 			case BUILD_BLOB_ASN1_DER:
-			{
-				va_start(args, part);
-				this->key = load(va_arg(args, chunk_t));
-				va_end(args);
-				return;
-			}
-			default:
+				blob = va_arg(args, chunk_t);
+				continue;
+			case BUILD_END:
 				break;
+			default:
+				return NULL;
 		}
+		break;
 	}
-	if (this->key)
-	{
-		destroy((private_openssl_ec_public_key_t*)this->key);
-	}
-	builder_cancel(&this->public);
-}
-
-/**
- * Builder construction function
- */
-builder_t *openssl_ec_public_key_builder(key_type_t type)
-{
-	private_builder_t *this;
-
-	if (type != KEY_ECDSA)
+	this = create_empty();
+	this->ec = d2i_EC_PUBKEY(NULL, (const u_char**)&blob.ptr, blob.len);
+	if (!this->ec)
 	{
+		destroy(this);
 		return NULL;
 	}
-
-	this = malloc_thing(private_builder_t);
-
-	this->key = NULL;
-	this->public.add = (void(*)(builder_t *this, builder_part_t part, ...))add;
-	this->public.build = (void*(*)(builder_t *this))build;
-
 	return &this->public;
 }
 
diff --git a/src/libstrongswan/plugins/openssl/openssl_ec_public_key.h b/src/libstrongswan/plugins/openssl/openssl_ec_public_key.h
index bdbb2fe6e..29d607d38 100644
--- a/src/libstrongswan/plugins/openssl/openssl_ec_public_key.h
+++ b/src/libstrongswan/plugins/openssl/openssl_ec_public_key.h
@@ -23,6 +23,7 @@
 
 typedef struct openssl_ec_public_key_t openssl_ec_public_key_t;
 
+#include <credentials/builder.h>
 #include <credentials/keys/public_key.h>
 
 /**
@@ -37,11 +38,15 @@ struct openssl_ec_public_key_t {
 };
 
 /**
- * Create the builder for a public key.
+ * Load a ECDSA public key using OpenSSL.
+ *
+ * Accepts a BUILD_BLOB_ASN1_DER argument.
  *
  * @param type		type of the key, must be KEY_ECDSA
- * @return 			builder instance
+ * @param args		builder_part_t argument list
+ * @return 			loaded key, NULL on failure
  */
-builder_t *openssl_ec_public_key_builder(key_type_t type);
+openssl_ec_public_key_t *openssl_ec_public_key_load(key_type_t type,
+													va_list args);
 
 #endif /** OPENSSL_EC_PUBLIC_KEY_H_ @}*/
diff --git a/src/libstrongswan/plugins/openssl/openssl_plugin.c b/src/libstrongswan/plugins/openssl/openssl_plugin.c
index 1cc6f7ce6..a6089c839 100644
--- a/src/libstrongswan/plugins/openssl/openssl_plugin.c
+++ b/src/libstrongswan/plugins/openssl/openssl_plugin.c
@@ -175,13 +175,19 @@ static void destroy(private_openssl_plugin_t *this)
 	lib->crypto->remove_dh(lib->crypto,
 					(dh_constructor_t)openssl_ec_diffie_hellman_create);
 	lib->creds->remove_builder(lib->creds,
-					(builder_constructor_t)openssl_rsa_private_key_builder);
+					(builder_function_t)openssl_rsa_private_key_load);
 	lib->creds->remove_builder(lib->creds,
-					(builder_constructor_t)openssl_rsa_public_key_builder);
+					(builder_function_t)openssl_rsa_private_key_gen);
 	lib->creds->remove_builder(lib->creds,
-					(builder_constructor_t)openssl_ec_private_key_builder);
+					(builder_function_t)openssl_rsa_private_key_connect);
 	lib->creds->remove_builder(lib->creds,
-					(builder_constructor_t)openssl_ec_public_key_builder);
+					(builder_function_t)openssl_rsa_public_key_load);
+	lib->creds->remove_builder(lib->creds,
+					(builder_function_t)openssl_ec_private_key_load);
+	lib->creds->remove_builder(lib->creds,
+					(builder_function_t)openssl_ec_private_key_gen);
+	lib->creds->remove_builder(lib->creds,
+					(builder_function_t)openssl_ec_public_key_load);
 
 	ENGINE_cleanup();
 	EVP_cleanup();
@@ -282,15 +288,22 @@ plugin_t *plugin_create()
 
 	/* rsa */
 	lib->creds->add_builder(lib->creds, CRED_PRIVATE_KEY, KEY_RSA,
-						(builder_constructor_t)openssl_rsa_private_key_builder);
+					(builder_function_t)openssl_rsa_private_key_load);
+	lib->creds->add_builder(lib->creds, CRED_PRIVATE_KEY, KEY_RSA,
+					(builder_function_t)openssl_rsa_private_key_gen);
+	lib->creds->add_builder(lib->creds, CRED_PRIVATE_KEY, KEY_RSA,
+					(builder_function_t)openssl_rsa_private_key_connect);
 	lib->creds->add_builder(lib->creds, CRED_PUBLIC_KEY, KEY_RSA,
-						(builder_constructor_t)openssl_rsa_public_key_builder);
+					(builder_function_t)openssl_rsa_public_key_load);
 
 	/* ec */
 	lib->creds->add_builder(lib->creds, CRED_PRIVATE_KEY, KEY_ECDSA,
-						(builder_constructor_t)openssl_ec_private_key_builder);
+					(builder_function_t)openssl_ec_private_key_load);
+	lib->creds->add_builder(lib->creds, CRED_PRIVATE_KEY, KEY_ECDSA,
+					(builder_function_t)openssl_ec_private_key_gen);
 	lib->creds->add_builder(lib->creds, CRED_PUBLIC_KEY, KEY_ECDSA,
-						(builder_constructor_t)openssl_ec_public_key_builder);
+					(builder_function_t)openssl_ec_public_key_load);
 
 	return &this->public.plugin;
 }
+
diff --git a/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.c b/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.c
index c68987856..ce65cddb4 100644
--- a/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.c
+++ b/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.c
@@ -288,26 +288,64 @@ static private_openssl_rsa_private_key_t *create_empty(void)
 }
 
 /**
- * Generate an RSA key of specified key size
+ * See header.
  */
-static openssl_rsa_private_key_t *generate(size_t key_size)
+openssl_rsa_private_key_t *openssl_rsa_private_key_gen(key_type_t type,
+													   va_list args)
 {
-	private_openssl_rsa_private_key_t *this = create_empty();
+	private_openssl_rsa_private_key_t *this;
+	u_int key_size = 0;
 
+	while (TRUE)
+	{
+		switch (va_arg(args, builder_part_t))
+		{
+			case BUILD_KEY_SIZE:
+				key_size = va_arg(args, u_int);
+				continue;
+			case BUILD_END:
+				break;
+			default:
+				return NULL;
+		}
+		break;
+	}
+	if (!key_size)
+	{
+		return NULL;
+	}
+	this = create_empty();
 	this->rsa = RSA_generate_key(key_size, PUBLIC_EXPONENT, NULL, NULL);
 
 	return &this->public;
 }
 
 /**
- * load private key from an ASN1 encoded blob
+ * See header
  */
-static openssl_rsa_private_key_t *load(chunk_t blob)
+openssl_rsa_private_key_t *openssl_rsa_private_key_load(key_type_t type,
+														va_list args)
 {
-	u_char *p = blob.ptr;
-	private_openssl_rsa_private_key_t *this = create_empty();
+	private_openssl_rsa_private_key_t *this;
+	chunk_t blob = chunk_empty;
 
-	this->rsa = d2i_RSAPrivateKey(NULL, (const u_char**)&p, blob.len);
+	while (TRUE)
+	{
+		switch (va_arg(args, builder_part_t))
+		{
+			case BUILD_BLOB_ASN1_DER:
+				blob = va_arg(args, chunk_t);
+				continue;
+			case BUILD_END:
+				break;
+			default:
+				return NULL;
+		}
+		break;
+	}
+
+	this = create_empty();
+	this->rsa = d2i_RSAPrivateKey(NULL, (const u_char**)&blob.ptr, blob.len);
 	if (!this->rsa)
 	{
 		destroy(this);
@@ -322,41 +360,67 @@ static openssl_rsa_private_key_t *load(chunk_t blob)
 }
 
 /**
- * load private key from a smart card
+ * See header.
  */
-static openssl_rsa_private_key_t *load_from_smartcard(char *keyid, char *pin)
+openssl_rsa_private_key_t *openssl_rsa_private_key_connect(key_type_t type,
+														   va_list args)
 {
-	private_openssl_rsa_private_key_t *this = NULL;
+	private_openssl_rsa_private_key_t *this;
+	char *keyid = NULL, *pin = NULL;
 	EVP_PKEY *key;
-	char *engine_id = lib->settings->get_str(lib->settings,
-								"library.plugins.openssl.engine_id", "pkcs11");
+	char *engine_id;
+	ENGINE *engine;
+
+	while (TRUE)
+	{
+		switch (va_arg(args, builder_part_t))
+		{
+			case BUILD_SMARTCARD_KEYID:
+				keyid = va_arg(args, char*);
+				continue;
+			case BUILD_SMARTCARD_PIN:
+				pin = va_arg(args, char*);
+				continue;
+			case BUILD_END:
+				break;
+			default:
+				return NULL;
+		}
+		break;
+	}
+	if (!keyid || !pin)
+	{
+		return NULL;
+	}
 
-	ENGINE *engine = ENGINE_by_id(engine_id);
+	engine_id = lib->settings->get_str(lib->settings,
+								"library.plugins.openssl.engine_id", "pkcs11");
+	engine = ENGINE_by_id(engine_id);
 	if (!engine)
 	{
 		DBG1("engine '%s' is not available", engine_id);
 		return NULL;
 	}
-
 	if (!ENGINE_init(engine))
 	{
 		DBG1("failed to initialize engine '%s'", engine_id);
-		goto error;
+		ENGINE_free(engine);
+		return NULL;
 	}
-
 	if (!ENGINE_ctrl_cmd_string(engine, "PIN", pin, 0))
 	{
 		DBG1("failed to set PIN on engine '%s'", engine_id);
-		goto error;
+		ENGINE_free(engine);
+		return NULL;
 	}
 
 	key = ENGINE_load_private_key(engine, keyid, NULL, NULL);
-
 	if (!key)
 	{
-		DBG1("failed to load private key with ID '%s' from engine '%s'", keyid,
-				engine_id);
-		goto error;
+		DBG1("failed to load private key with ID '%s' from engine '%s'",
+			 keyid, engine_id);
+		ENGINE_free(engine);
+		return NULL;
 	}
 	ENGINE_free(engine);
 
@@ -365,113 +429,5 @@ static openssl_rsa_private_key_t *load_from_smartcard(char *keyid, char *pin)
 	this->engine = TRUE;
 
 	return &this->public;
-
-error:
-	ENGINE_free(engine);
-	return NULL;
-}
-
-typedef struct private_builder_t private_builder_t;
-
-/**
- * Builder implementation for key loading/generation
- */
-struct private_builder_t {
-	/** implements the builder interface */
-	builder_t public;
-	/** loaded/generated private key */
-	openssl_rsa_private_key_t *key;
-	/** temporary stored smartcard key ID */
-	char *keyid;
-	/** temporary stored smartcard pin */
-	char *pin;
-};
-
-/**
- * Implementation of builder_t.build
- */
-static openssl_rsa_private_key_t *build(private_builder_t *this)
-{
-	openssl_rsa_private_key_t *key = this->key;
-
-	if (this->keyid && this->pin)
-	{
-		key = load_from_smartcard(this->keyid, this->pin);
-	}
-	free(this);
-	return key;
-}
-
-/**
- * Implementation of builder_t.add
- */
-static void add(private_builder_t *this, builder_part_t part, ...)
-{
-	if (!this->key)
-	{
-		va_list args;
-
-		switch (part)
-		{
-			case BUILD_BLOB_ASN1_DER:
-			{
-				va_start(args, part);
-				this->key = load(va_arg(args, chunk_t));
-				va_end(args);
-				return;
-			}
-			case BUILD_KEY_SIZE:
-			{
-				va_start(args, part);
-				this->key = generate(va_arg(args, u_int));
-				va_end(args);
-				return;
-			}
-			case BUILD_SMARTCARD_KEYID:
-			{
-				va_start(args, part);
-				this->keyid = va_arg(args, char*);
-				va_end(args);
-				return;
-			}
-			case BUILD_SMARTCARD_PIN:
-			{
-				va_start(args, part);
-				this->pin = va_arg(args, char*);
-				va_end(args);
-				return;
-			}
-			default:
-				break;
-		}
-	}
-	if (this->key)
-	{
-		destroy((private_openssl_rsa_private_key_t*)this->key);
-	}
-	builder_cancel(&this->public);
-}
-
-/**
- * Builder construction function
- */
-builder_t *openssl_rsa_private_key_builder(key_type_t type)
-{
-	private_builder_t *this;
-
-	if (type != KEY_RSA)
-	{
-		return NULL;
-	}
-
-	this = malloc_thing(private_builder_t);
-
-	this->key = NULL;
-	this->public.add = (void(*)(builder_t *this, builder_part_t part, ...))add;
-	this->public.build = (void*(*)(builder_t *this))build;
-	this->keyid = NULL;
-	this->pin = NULL;
-
-	return &this->public;
 }
 
diff --git a/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.h b/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.h
index 53ec44b28..079dfa46a 100644
--- a/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.h
+++ b/src/libstrongswan/plugins/openssl/openssl_rsa_private_key.h
@@ -21,6 +21,7 @@
 #ifndef OPENSSL_RSA_PRIVATE_KEY_H_
 #define OPENSSL_RSA_PRIVATE_KEY_H_
 
+#include <credentials/builder.h>
 #include <credentials/keys/private_key.h>
 
 typedef struct openssl_rsa_private_key_t openssl_rsa_private_key_t;
@@ -37,11 +38,40 @@ struct openssl_rsa_private_key_t {
 };
 
 /**
- * Create the builder for a private key.
+ * Generate a RSA private key using OpenSSL.
+ *
+ * Accepts the BUILD_KEY_SIZE argument.
+ *
+ * @param type		type of the key, must be KEY_RSA
+ * @param args		builder_part_t argument list
+ * @return 			generated key, NULL on failure
+ */
+openssl_rsa_private_key_t *openssl_rsa_private_key_gen(key_type_t type,
+													   va_list args);
+
+/**
+ * Load a RSA private key using OpenSSL.
+ *
+ * Accepts a BUILD_BLOB_ASN1_DER argument.
+ *
+ * @param type		type of the key, must be KEY_RSA
+ * @param args		builder_part_t argument list
+ * @return 			loaded key, NULL on failure
+ */
+openssl_rsa_private_key_t *openssl_rsa_private_key_load(key_type_t type,
+														va_list args);
+
+/**
+ * Connect to a RSA private key on a smartcard.
+ *
+ * Accepts the BUILD_SMARTCARD_KEYID and the BUILD_SMARTCARD_PIN
+ * arguments.
  *
  * @param type		type of the key, must be KEY_RSA
- * @return 			builder instance
+ * @param args		builder_part_t argument list
+ * @return 			loaded key, NULL on failure
  */
-builder_t *openssl_rsa_private_key_builder(key_type_t type);
+openssl_rsa_private_key_t *openssl_rsa_private_key_connect(key_type_t type,
+														   va_list args);
 
 #endif /** OPENSSL_RSA_PRIVATE_KEY_H_ @}*/
diff --git a/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.c b/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.c
index e30ab858b..67c2e47d4 100644
--- a/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.c
+++ b/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.c
@@ -298,93 +298,36 @@ static private_openssl_rsa_public_key_t *create_empty()
 }
 
 /**
- * Load a public key from an ASN1 encoded blob
+ * See header.
  */
-static openssl_rsa_public_key_t *load(chunk_t blob)
+openssl_rsa_public_key_t *openssl_rsa_public_key_load(key_type_t type,
+													  va_list args)
 {
-	u_char *p = blob.ptr;
-	private_openssl_rsa_public_key_t *this = create_empty();
+	private_openssl_rsa_public_key_t *this;
+	chunk_t blob;
 
-	this->rsa = d2i_RSAPublicKey(NULL, (const u_char**)&p, blob.len);
-	if (!this->rsa)
-	{
-		destroy(this);
-		return NULL;
-	}
-
-	return &this->public;
-}
-
-typedef struct private_builder_t private_builder_t;
-
-/**
- * Builder implementation for key loading
- */
-struct private_builder_t {
-	/** implements the builder interface */
-	builder_t public;
-	/** loaded public key */
-	openssl_rsa_public_key_t *key;
-};
-
-/**
- * Implementation of builder_t.build
- */
-static openssl_rsa_public_key_t *build(private_builder_t *this)
-{
-	openssl_rsa_public_key_t *key = this->key;
-
-	free(this);
-	return key;
-}
-
-/**
- * Implementation of builder_t.add
- */
-static void add(private_builder_t *this, builder_part_t part, ...)
-{
-	if (!this->key)
+	while (TRUE)
 	{
-		va_list args;
-
-		switch (part)
+		switch (va_arg(args, builder_part_t))
 		{
 			case BUILD_BLOB_ASN1_DER:
-			{
-				va_start(args, part);
-				this->key = load(va_arg(args, chunk_t));
-				va_end(args);
-				return;
-			}
-			default:
+				blob = va_arg(args, chunk_t);
+				continue;
+			case BUILD_END:
 				break;
+			default:
+				return NULL;
 		}
+		break;
 	}
-	if (this->key)
-	{
-		destroy((private_openssl_rsa_public_key_t*)this->key);
-	}
-	builder_cancel(&this->public);
-}
 
-/**
- * Builder construction function
- */
-builder_t *openssl_rsa_public_key_builder(key_type_t type)
-{
-	private_builder_t *this;
-
-	if (type != KEY_RSA)
+	this = create_empty();
+	this->rsa = d2i_RSAPublicKey(NULL, (const u_char**)&blob.ptr, blob.len);
+	if (!this->rsa)
 	{
+		destroy(this);
 		return NULL;
 	}
-
-	this = malloc_thing(private_builder_t);
-
-	this->key = NULL;
-	this->public.add = (void(*)(builder_t *this, builder_part_t part, ...))add;
-	this->public.build = (void*(*)(builder_t *this))build;
-
 	return &this->public;
 }
 
diff --git a/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.h b/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.h
index ff99ddbc5..620aa51ce 100644
--- a/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.h
+++ b/src/libstrongswan/plugins/openssl/openssl_rsa_public_key.h
@@ -37,11 +37,15 @@ struct openssl_rsa_public_key_t {
 };
 
 /**
- * Create the builder for a public key.
+ * Load a RSA public key using OpenSSL.
+ *
+ * Accepts a BUILD_BLOB_ASN1_DER argument.
  *
  * @param type		type of the key, must be KEY_RSA
- * @return 			builder instance
+ * @param args		builder_part_t argument list
+ * @return 			loaded key, NULL on failure
  */
-builder_t *openssl_rsa_public_key_builder(key_type_t type);
+openssl_rsa_public_key_t *openssl_rsa_public_key_load(key_type_t type,
+													  va_list args);
 
 #endif /** OPENSSL_RSA_PUBLIC_KEY_H_ @}*/