diff --git a/src/libcharon/plugins/eap_aka/eap_aka_peer.c b/src/libcharon/plugins/eap_aka/eap_aka_peer.c
index 8c392405e..8a5fbe690 100644
--- a/src/libcharon/plugins/eap_aka/eap_aka_peer.c
+++ b/src/libcharon/plugins/eap_aka/eap_aka_peer.c
@@ -80,13 +80,31 @@ struct private_eap_aka_peer_t {
 	u_int16_t counter;
 };
 
+/**
+ * Generate a payload from a message, destroy message
+ */
+static bool generate_payload(simaka_message_t *message, chunk_t data,
+							 eap_payload_t **out)
+{
+	chunk_t chunk;
+	bool ok;
+
+	ok = message->generate(message, data, &chunk);
+	if (ok)
+	{
+		*out = eap_payload_create_data_own(chunk);
+	}
+	message->destroy(message);
+	return ok;
+}
+
 /**
  * Create a AKA_CLIENT_ERROR: "Unable to process"
  */
-static eap_payload_t* create_client_error(private_eap_aka_peer_t *this)
+static bool create_client_error(private_eap_aka_peer_t *this,
+								eap_payload_t **out)
 {
 	simaka_message_t *message;
-	eap_payload_t *out;
 	u_int16_t encoded;
 
 	DBG1(DBG_IKE, "sending client error '%N'",
@@ -97,9 +115,8 @@ static eap_payload_t* create_client_error(private_eap_aka_peer_t *this)
 	encoded = htons(AKA_UNABLE_TO_PROCESS);
 	message->add_attribute(message, AT_CLIENT_ERROR_CODE,
 						   chunk_create((char*)&encoded, sizeof(encoded)));
-	out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-	return out;
+
+	return generate_payload(message, chunk_empty, out);
 }
 
 /**
@@ -134,8 +151,11 @@ static status_t process_identity(private_eap_aka_peer_t *this,
 			default:
 				if (!simaka_attribute_skippable(type))
 				{
-					*out = create_client_error(this);
 					enumerator->destroy(enumerator);
+					if (!create_client_error(this, out))
+					{
+						return FAILED;
+					}
 					return NEED_MORE;
 				}
 				break;
@@ -175,9 +195,10 @@ static status_t process_identity(private_eap_aka_peer_t *this,
 	{
 		message->add_attribute(message, AT_IDENTITY, id);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	return NEED_MORE;
 }
 
@@ -210,8 +231,11 @@ static status_t process_challenge(private_eap_aka_peer_t *this,
 			default:
 				if (!simaka_attribute_skippable(type))
 				{
-					*out = create_client_error(this);
 					enumerator->destroy(enumerator);
+					if (!create_client_error(this, out))
+					{
+						return FAILED;
+					}
 					return NEED_MORE;
 				}
 				break;
@@ -222,7 +246,10 @@ static status_t process_challenge(private_eap_aka_peer_t *this,
 	if (!rand.len || !autn.len)
 	{
 		DBG1(DBG_IKE, "received invalid EAP-AKA challenge message");
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -237,9 +264,10 @@ static status_t process_challenge(private_eap_aka_peer_t *this,
 									AKA_SYNCHRONIZATION_FAILURE, this->crypto);
 		message->add_attribute(message, AT_AUTS,
 							   chunk_create(auts, AKA_AUTS_LEN));
-		*out = eap_payload_create_data_own(message->generate(message,
-										   chunk_empty));
-		message->destroy(message);
+		if (!generate_payload(message, chunk_empty, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 	if (status != SUCCESS)
@@ -248,9 +276,10 @@ static status_t process_challenge(private_eap_aka_peer_t *this,
 			 this->permanent, simaka_subtype_names, AKA_AUTHENTICATION_REJECT);
 		message = simaka_message_create(FALSE, in->get_identifier(in), EAP_AKA,
 										AKA_AUTHENTICATION_REJECT, this->crypto);
-		*out = eap_payload_create_data_own(message->generate(message,
-										   chunk_empty));
-		message->destroy(message);
+		if (!generate_payload(message, chunk_empty, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -270,7 +299,10 @@ static status_t process_challenge(private_eap_aka_peer_t *this,
 	 * reading encrypted attributes */
 	if (!in->verify(in, chunk_empty) || !in->parse(in))
 	{
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -300,8 +332,10 @@ static status_t process_challenge(private_eap_aka_peer_t *this,
 	message = simaka_message_create(FALSE, this->identifier, EAP_AKA,
 									AKA_CHALLENGE, this->crypto);
 	message->add_attribute(message, AT_RES, chunk_create(res, res_len));
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	return NEED_MORE;
 }
 
@@ -332,7 +366,10 @@ static status_t process_reauthentication(private_eap_aka_peer_t *this,
 	{
 		DBG1(DBG_IKE, "received %N, but not expected",
 			 simaka_subtype_names, AKA_REAUTHENTICATION);
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -342,7 +379,10 @@ static status_t process_reauthentication(private_eap_aka_peer_t *this,
 	/* verify MAC and parse again with decryption key */
 	if (!in->verify(in, chunk_empty) || !in->parse(in))
 	{
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -363,8 +403,11 @@ static status_t process_reauthentication(private_eap_aka_peer_t *this,
 			default:
 				if (!simaka_attribute_skippable(type))
 				{
-					*out = create_client_error(this);
 					enumerator->destroy(enumerator);
+					if (!create_client_error(this, out))
+					{
+						return FAILED;
+					}
 					return NEED_MORE;
 				}
 				break;
@@ -375,7 +418,10 @@ static status_t process_reauthentication(private_eap_aka_peer_t *this,
 	if (!nonce.len || !counter.len)
 	{
 		DBG1(DBG_IKE, "EAP-AKA/Request/Reauthentication message incomplete");
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -403,8 +449,10 @@ static status_t process_reauthentication(private_eap_aka_peer_t *this,
 		}
 	}
 	message->add_attribute(message, AT_COUNTER, counter);
-	*out = eap_payload_create_data_own(message->generate(message, nonce));
-	message->destroy(message);
+	if (!generate_payload(message, nonce, out))
+	{
+		return FAILED;
+	}
 	return NEED_MORE;
 }
 
@@ -454,13 +502,17 @@ static status_t process_notification(private_eap_aka_peer_t *this,
 	{	/* empty notification reply */
 		message = simaka_message_create(FALSE, this->identifier, EAP_AKA,
 										AKA_NOTIFICATION, this->crypto);
-		*out = eap_payload_create_data_own(message->generate(message,
-															 chunk_empty));
-		message->destroy(message);
+		if (!generate_payload(message, chunk_empty, out))
+		{
+			return FAILED;
+		}
 	}
 	else
 	{
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 	}
 	return NEED_MORE;
 }
@@ -478,13 +530,19 @@ METHOD(eap_method_t, process, status_t,
 	message = simaka_message_create_from_payload(in->get_data(in), this->crypto);
 	if (!message)
 	{
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 	if (!message->parse(message))
 	{
 		message->destroy(message);
-		*out = create_client_error(this);
+		if (!create_client_error(this, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 	switch (message->get_subtype(message))
@@ -504,8 +562,14 @@ METHOD(eap_method_t, process, status_t,
 		default:
 			DBG1(DBG_IKE, "unable to process EAP-AKA subtype %N",
 				 simaka_subtype_names, message->get_subtype(message));
-			*out = create_client_error(this);
-			status = NEED_MORE;
+			if (!create_client_error(this, out))
+			{
+				status = FAILED;
+			}
+			else
+			{
+				status = NEED_MORE;
+			}
 			break;
 	}
 	message->destroy(message);
diff --git a/src/libcharon/plugins/eap_aka/eap_aka_server.c b/src/libcharon/plugins/eap_aka/eap_aka_server.c
index 319cc45be..ac4cd15d7 100644
--- a/src/libcharon/plugins/eap_aka/eap_aka_server.c
+++ b/src/libcharon/plugins/eap_aka/eap_aka_server.c
@@ -118,6 +118,24 @@ struct private_eap_aka_server_t {
 	bool synchronized;
 };
 
+/**
+ * Generate a payload from a message, destroy message
+ */
+static bool generate_payload(simaka_message_t *message, chunk_t data,
+							 eap_payload_t **out)
+{
+	chunk_t chunk;
+	bool ok;
+
+	ok = message->generate(message, data, &chunk);
+	if (ok)
+	{
+		*out = eap_payload_create_data_own(chunk);
+	}
+	message->destroy(message);
+	return ok;
+}
+
 /**
  * Create EAP-AKA/Request/Identity message
  */
@@ -139,9 +157,10 @@ static status_t identity(private_eap_aka_server_t *this, eap_payload_t **out)
 	{
 		message->add_attribute(message, AT_PERMANENT_ID_REQ, chunk_empty);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	this->pending = AKA_IDENTITY;
 	return NEED_MORE;
 }
@@ -190,6 +209,7 @@ static status_t challenge(private_eap_aka_server_t *this, eap_payload_t **out)
 	message->add_attribute(message, AT_RAND, this->rand);
 	message->add_attribute(message, AT_AUTN, chunk_create(autn, AKA_AUTN_LEN));
 	id = this->mgr->provider_gen_reauth(this->mgr, this->permanent, mk.ptr);
+	free(mk.ptr);
 	if (id)
 	{
 		message->add_attribute(message, AT_NEXT_REAUTH_ID,
@@ -203,10 +223,10 @@ static status_t challenge(private_eap_aka_server_t *this, eap_payload_t **out)
 							   id->get_encoding(id));
 		id->destroy(id);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-
-	free(mk.ptr);
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	this->pending = AKA_CHALLENGE;
 	return NEED_MORE;
 }
@@ -247,9 +267,10 @@ static status_t reauthenticate(private_eap_aka_server_t *this,
 							   next->get_encoding(next));
 		next->destroy(next);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	this->pending = SIM_REAUTHENTICATION;
 	return NEED_MORE;
 }
diff --git a/src/libcharon/plugins/eap_sim/eap_sim_peer.c b/src/libcharon/plugins/eap_sim/eap_sim_peer.c
index 1d1ab99e0..f0a48255d 100644
--- a/src/libcharon/plugins/eap_sim/eap_sim_peer.c
+++ b/src/libcharon/plugins/eap_sim/eap_sim_peer.c
@@ -105,14 +105,31 @@ struct private_eap_sim_peer_t {
 /* version of SIM protocol we speak */
 static chunk_t version = chunk_from_chars(0x00,0x01);
 
+/**
+ * Generate a payload from a message, destroy message
+ */
+static bool generate_payload(simaka_message_t *message, chunk_t data,
+							 eap_payload_t **out)
+{
+	chunk_t chunk;
+	bool ok;
+
+	ok = message->generate(message, data, &chunk);
+	if (ok)
+	{
+		*out = eap_payload_create_data_own(chunk);
+	}
+	message->destroy(message);
+	return ok;
+}
+
 /**
  * Create a SIM_CLIENT_ERROR
  */
-static eap_payload_t* create_client_error(private_eap_sim_peer_t *this,
-										  simaka_client_error_t code)
+static bool create_client_error(private_eap_sim_peer_t *this,
+								simaka_client_error_t code, eap_payload_t **out)
 {
 	simaka_message_t *message;
-	eap_payload_t *out;
 	u_int16_t encoded;
 
 	DBG1(DBG_IKE, "sending client error '%N'", simaka_client_error_names, code);
@@ -122,9 +139,7 @@ static eap_payload_t* create_client_error(private_eap_sim_peer_t *this,
 	encoded = htons(code);
 	message->add_attribute(message, AT_CLIENT_ERROR_CODE,
 						   chunk_create((char*)&encoded, sizeof(encoded)));
-	out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-	return out;
+	return generate_payload(message, chunk_empty, out);
 }
 
 /**
@@ -175,8 +190,11 @@ static status_t process_start(private_eap_sim_peer_t *this,
 			default:
 				if (!simaka_attribute_skippable(type))
 				{
-					*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
 					enumerator->destroy(enumerator);
+					if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+					{
+						return FAILED;
+					}
 					return NEED_MORE;
 				}
 				break;
@@ -187,7 +205,10 @@ static status_t process_start(private_eap_sim_peer_t *this,
 	if (!supported)
 	{
 		DBG1(DBG_IKE, "server does not support EAP-SIM version number 1");
-		*out = create_client_error(this, SIM_UNSUPPORTED_VERSION);
+		if (!create_client_error(this, SIM_UNSUPPORTED_VERSION, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -234,9 +255,10 @@ static status_t process_start(private_eap_sim_peer_t *this,
 	{
 		message->add_attribute(message, AT_IDENTITY, id);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	return NEED_MORE;
 }
 
@@ -270,8 +292,11 @@ static status_t process_challenge(private_eap_sim_peer_t *this,
 			default:
 				if (!simaka_attribute_skippable(type))
 				{
-					*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
 					enumerator->destroy(enumerator);
+					if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+					{
+						return FAILED;
+					}
 					return NEED_MORE;
 				}
 				break;
@@ -285,7 +310,10 @@ static status_t process_challenge(private_eap_sim_peer_t *this,
 		memeq(rands.ptr, rands.ptr + SIM_RAND_LEN, SIM_RAND_LEN))
 	{
 		DBG1(DBG_IKE, "no valid AT_RAND received");
-		*out = create_client_error(this, SIM_INSUFFICIENT_CHALLENGES);
+		if (!create_client_error(this, SIM_INSUFFICIENT_CHALLENGES, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 	/* get two or three KCs/SRESes from SIM using RANDs */
@@ -297,7 +325,10 @@ static status_t process_challenge(private_eap_sim_peer_t *this,
 										 rands.ptr, sres.ptr, kc.ptr))
 		{
 			DBG1(DBG_IKE, "unable to get EAP-SIM triplet");
-			*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+			if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+			{
+				return FAILED;
+			}
 			return NEED_MORE;
 		}
 		DBG3(DBG_IKE, "got triplet for RAND %b\n  Kc %b\n  SRES %b",
@@ -322,7 +353,10 @@ static status_t process_challenge(private_eap_sim_peer_t *this,
 	 * parse() again after key derivation, reading encrypted attributes */
 	if (!in->verify(in, this->nonce) || !in->parse(in))
 	{
-		*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+		if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -352,8 +386,10 @@ static status_t process_challenge(private_eap_sim_peer_t *this,
 	/* build response with AT_MAC, built over "EAP packet | n*SRES" */
 	message = simaka_message_create(FALSE, this->identifier, EAP_SIM,
 									SIM_CHALLENGE, this->crypto);
-	*out = eap_payload_create_data_own(message->generate(message, sreses));
-	message->destroy(message);
+	if (!generate_payload(message, sreses, out))
+	{
+		return FAILED;
+	}
 	return NEED_MORE;
 }
 
@@ -384,7 +420,10 @@ static status_t process_reauthentication(private_eap_sim_peer_t *this,
 	{
 		DBG1(DBG_IKE, "received %N, but not expected",
 			 simaka_subtype_names, SIM_REAUTHENTICATION);
-		*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+		if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -394,7 +433,10 @@ static status_t process_reauthentication(private_eap_sim_peer_t *this,
 	/* verify MAC and parse again with decryption key */
 	if (!in->verify(in, chunk_empty) || !in->parse(in))
 	{
-		*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+		if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -415,8 +457,11 @@ static status_t process_reauthentication(private_eap_sim_peer_t *this,
 			default:
 				if (!simaka_attribute_skippable(type))
 				{
-					*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
 					enumerator->destroy(enumerator);
+					if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+					{
+						return FAILED;
+					}
 					return NEED_MORE;
 				}
 				break;
@@ -427,7 +472,10 @@ static status_t process_reauthentication(private_eap_sim_peer_t *this,
 	if (!nonce.len || !counter.len)
 	{
 		DBG1(DBG_IKE, "EAP-SIM/Request/Re-Authentication message incomplete");
-		*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+		if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 
@@ -455,8 +503,10 @@ static status_t process_reauthentication(private_eap_sim_peer_t *this,
 		}
 	}
 	message->add_attribute(message, AT_COUNTER, counter);
-	*out = eap_payload_create_data_own(message->generate(message, nonce));
-	message->destroy(message);
+	if (!generate_payload(message, nonce, out))
+	{
+		return FAILED;
+	}
 	return NEED_MORE;
 }
 
@@ -506,13 +556,17 @@ static status_t process_notification(private_eap_sim_peer_t *this,
 	{	/* empty notification reply */
 		message = simaka_message_create(FALSE, this->identifier, EAP_SIM,
 										SIM_NOTIFICATION, this->crypto);
-		*out = eap_payload_create_data_own(message->generate(message,
-										   chunk_empty));
-		message->destroy(message);
+		if (!generate_payload(message, chunk_empty, out))
+		{
+			return FAILED;
+		}
 	}
 	else
 	{
-		*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+		if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+		{
+			return FAILED;
+		}
 	}
 	return NEED_MORE;
 }
@@ -529,13 +583,19 @@ METHOD(eap_method_t, process, status_t,
 	message = simaka_message_create_from_payload(in->get_data(in), this->crypto);
 	if (!message)
 	{
-		*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+		if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 	if (!message->parse(message))
 	{
 		message->destroy(message);
-		*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
+		if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+		{
+			return FAILED;
+		}
 		return NEED_MORE;
 	}
 	switch (message->get_subtype(message))
@@ -555,8 +615,14 @@ METHOD(eap_method_t, process, status_t,
 		default:
 			DBG1(DBG_IKE, "unable to process EAP-SIM subtype %N",
 				 simaka_subtype_names, message->get_subtype(message));
-			*out = create_client_error(this, SIM_UNABLE_TO_PROCESS);
-			status = NEED_MORE;
+			if (!create_client_error(this, SIM_UNABLE_TO_PROCESS, out))
+			{
+				status = FAILED;
+			}
+			else
+			{
+				status = NEED_MORE;
+			}
 			break;
 	}
 	message->destroy(message);
diff --git a/src/libcharon/plugins/eap_sim/eap_sim_server.c b/src/libcharon/plugins/eap_sim/eap_sim_server.c
index a965476eb..a88ce5706 100644
--- a/src/libcharon/plugins/eap_sim/eap_sim_server.c
+++ b/src/libcharon/plugins/eap_sim/eap_sim_server.c
@@ -113,6 +113,24 @@ struct private_eap_sim_server_t {
 /* version of SIM protocol we speak */
 static chunk_t version = chunk_from_chars(0x00,0x01);
 
+/**
+ * Generate a payload from a message, destroy message
+ */
+static bool generate_payload(simaka_message_t *message, chunk_t data,
+							 eap_payload_t **out)
+{
+	chunk_t chunk;
+	bool ok;
+
+	ok = message->generate(message, data, &chunk);
+	if (ok)
+	{
+		*out = eap_payload_create_data_own(chunk);
+	}
+	message->destroy(message);
+	return ok;
+}
+
 METHOD(eap_method_t, initiate, status_t,
 	private_eap_sim_server_t *this, eap_payload_t **out)
 {
@@ -133,9 +151,10 @@ METHOD(eap_method_t, initiate, status_t,
 	{
 		message->add_attribute(message, AT_PERMANENT_ID_REQ, chunk_empty);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	this->pending = SIM_START;
 	return NEED_MORE;
 }
@@ -176,9 +195,10 @@ static status_t reauthenticate(private_eap_sim_server_t *this,
 							   next->get_encoding(next));
 		next->destroy(next);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, chunk_empty));
-	message->destroy(message);
-
+	if (!generate_payload(message, chunk_empty, out))
+	{
+		return FAILED;
+	}
 	this->pending = SIM_REAUTHENTICATION;
 	return NEED_MORE;
 }
@@ -393,6 +413,7 @@ static status_t process_start(private_eap_sim_server_t *this,
 									SIM_CHALLENGE, this->crypto);
 	message->add_attribute(message, AT_RAND, rands);
 	id = this->mgr->provider_gen_reauth(this->mgr, this->permanent, mk.ptr);
+	free(mk.ptr);
 	if (id)
 	{
 		message->add_attribute(message, AT_NEXT_REAUTH_ID,
@@ -406,10 +427,10 @@ static status_t process_start(private_eap_sim_server_t *this,
 							   id->get_encoding(id));
 		id->destroy(id);
 	}
-	*out = eap_payload_create_data_own(message->generate(message, nonce));
-	message->destroy(message);
-
-	free(mk.ptr);
+	if (!generate_payload(message, nonce, out))
+	{
+		return FAILED;
+	}
 	this->pending = SIM_CHALLENGE;
 	return NEED_MORE;
 }
diff --git a/src/libsimaka/simaka_message.c b/src/libsimaka/simaka_message.c
index a5754b985..745f4d76c 100644
--- a/src/libsimaka/simaka_message.c
+++ b/src/libsimaka/simaka_message.c
@@ -599,8 +599,8 @@ METHOD(simaka_message_t, verify, bool,
 	return TRUE;
 }
 
-METHOD(simaka_message_t, generate, chunk_t,
-	private_simaka_message_t *this, chunk_t sigdata)
+METHOD(simaka_message_t, generate, bool,
+	private_simaka_message_t *this, chunk_t sigdata, chunk_t *gen)
 {
 	/* buffers large enough for messages we generate */
 	char out_buf[1024], encr_buf[512];
@@ -827,7 +827,8 @@ METHOD(simaka_message_t, generate, chunk_t,
 
 	call_hook(this, FALSE, FALSE);
 
-	return chunk_clone(out);
+	*gen = chunk_clone(out);
+	return TRUE;
 }
 
 METHOD(simaka_message_t, destroy, void,
diff --git a/src/libsimaka/simaka_message.h b/src/libsimaka/simaka_message.h
index 28fe21823..209067c70 100644
--- a/src/libsimaka/simaka_message.h
+++ b/src/libsimaka/simaka_message.h
@@ -236,9 +236,10 @@ struct simaka_message_t {
 	 * Generate a message, optionally encrypt attributes and create a MAC.
 	 *
 	 * @param sigdata	additional data to include in signature, if any
-	 * @return			allocated data of generated message
+	 * @param gen		allocated generated data, if successful
+	 * @return			TRUE if successful
 	 */
-	chunk_t (*generate)(simaka_message_t *this, chunk_t sigdata);
+	bool (*generate)(simaka_message_t *this, chunk_t sigdata, chunk_t *gen);
 
 	/**
 	 * Destroy a simaka_message_t.