iv_gen: aead_t implementations provide an IV generator

src/libstrongswan/plugins/gcm/gcm_aead.c

@@ -16,6 +16,7 @@
 #include "gcm_aead.h"
 
 #include <limits.h>
+#include <crypto/iv/iv_gen_seq.h>
 
 #define BLOCK_SIZE 16
 #define NONCE_SIZE 12
@@ -39,6 +40,11 @@ struct private_gcm_aead_t {
 	 */
 	crypter_t *crypter;
 
+	/**
+	 * IV generator.
+	 */
+	iv_gen_t *iv_gen;
+
 	/**
 	 * Size of the integrity check value
 	 */
@@ -337,6 +343,12 @@ METHOD(aead_t, get_iv_size, size_t,
 	return IV_SIZE;
 }
 
+METHOD(aead_t, get_iv_gen, iv_gen_t*,
+	private_gcm_aead_t *this)
+{
+	return this->iv_gen;
+}
+
 METHOD(aead_t, get_key_size, size_t,
 	private_gcm_aead_t *this)
 {
@@ -356,6 +368,7 @@ METHOD(aead_t, destroy, void,
 	private_gcm_aead_t *this)
 {
 	this->crypter->destroy(this->crypter);
+	this->iv_gen->destroy(this->iv_gen);
 	free(this);
 }
 
@@ -405,12 +418,14 @@ gcm_aead_t *gcm_aead_create(encryption_algorithm_t algo, size_t key_size)
 				.get_block_size = _get_block_size,
 				.get_icv_size = _get_icv_size,
 				.get_iv_size = _get_iv_size,
+				.get_iv_gen = _get_iv_gen,
 				.get_key_size = _get_key_size,
 				.set_key = _set_key,
 				.destroy = _destroy,
 			},
 		},
 		.crypter = lib->crypto->create_crypter(lib->crypto, algo, key_size),
+		.iv_gen = iv_gen_seq_create(),
 		.icv_size = icv_size,
 	);