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-rw-r--r--pceplib/pcep_session_logic.c689
1 files changed, 689 insertions, 0 deletions
diff --git a/pceplib/pcep_session_logic.c b/pceplib/pcep_session_logic.c
new file mode 100644
index 0000000..78d1072
--- /dev/null
+++ b/pceplib/pcep_session_logic.c
@@ -0,0 +1,689 @@
+/*
+ * This file is part of the PCEPlib, a PCEP protocol library.
+ *
+ * Copyright (C) 2020 Volta Networks https://voltanet.io/
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * Author : Brady Johnson <brady@voltanet.io>
+ *
+ */
+
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <errno.h>
+#include <limits.h>
+#include <pthread.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+
+#include "pcep_msg_encoding.h"
+#include "pcep_session_logic.h"
+#include "pcep_session_logic_internals.h"
+#include "pcep_timers.h"
+#include "pcep_utils_counters.h"
+#include "pcep_utils_ordered_list.h"
+#include "pcep_utils_logging.h"
+#include "pcep_utils_memory.h"
+
+/*
+ * public API function implementations for the session_logic
+ */
+
+pcep_session_logic_handle *session_logic_handle_ = NULL;
+pcep_event_queue *session_logic_event_queue_ = NULL;
+int session_id_ = 0;
+
+void send_pcep_open(pcep_session *session); /* forward decl */
+
+static bool run_session_logic_common(void)
+{
+ if (session_logic_handle_ != NULL) {
+ pcep_log(LOG_WARNING,
+ "%s: Session Logic is already initialized.", __func__);
+ return false;
+ }
+
+ session_logic_handle_ = pceplib_malloc(
+ PCEPLIB_INFRA, sizeof(pcep_session_logic_handle));
+ memset(session_logic_handle_, 0, sizeof(pcep_session_logic_handle));
+
+ session_logic_handle_->active = true;
+ session_logic_handle_->session_list =
+ ordered_list_initialize(pointer_compare_function);
+ session_logic_handle_->session_event_queue = queue_initialize();
+
+ /* Initialize the event queue */
+ session_logic_event_queue_ =
+ pceplib_malloc(PCEPLIB_INFRA, sizeof(pcep_event_queue));
+ session_logic_event_queue_->event_queue = queue_initialize();
+ if (pthread_mutex_init(&(session_logic_event_queue_->event_queue_mutex),
+ NULL)
+ != 0) {
+ pcep_log(
+ LOG_ERR,
+ "%s: Cannot initialize session_logic event queue mutex.",
+ __func__);
+ return false;
+ }
+
+ pthread_cond_init(&(session_logic_handle_->session_logic_cond_var),
+ NULL);
+
+ if (pthread_mutex_init(&(session_logic_handle_->session_logic_mutex),
+ NULL)
+ != 0) {
+ pcep_log(LOG_ERR, "%s: Cannot initialize session_logic mutex.",
+ __func__);
+ return false;
+ }
+
+ pthread_mutex_lock(&(session_logic_handle_->session_logic_mutex));
+ session_logic_handle_->session_logic_condition = true;
+ pthread_cond_signal(&(session_logic_handle_->session_logic_cond_var));
+ pthread_mutex_unlock(&(session_logic_handle_->session_logic_mutex));
+
+ if (pthread_mutex_init(&(session_logic_handle_->session_list_mutex),
+ NULL)
+ != 0) {
+ pcep_log(LOG_ERR, "%s: Cannot initialize session_list mutex.",
+ __func__);
+ return false;
+ }
+
+ return true;
+}
+
+
+bool run_session_logic()
+{
+ if (!run_session_logic_common()) {
+ return false;
+ }
+
+ if (pthread_create(&(session_logic_handle_->session_logic_thread), NULL,
+ session_logic_loop, session_logic_handle_)) {
+ pcep_log(LOG_ERR, "%s: Cannot initialize session_logic thread.",
+ __func__);
+ return false;
+ }
+
+ if (!initialize_timers(session_logic_timer_expire_handler)) {
+ pcep_log(LOG_ERR, "%s: Cannot initialize session_logic timers.",
+ __func__);
+ return false;
+ }
+
+ /* No need to call initialize_socket_comm_loop() since it will be
+ * called internally when the first socket_comm_session is created. */
+
+ return true;
+}
+
+
+bool run_session_logic_with_infra(pceplib_infra_config *infra_config)
+{
+ if (infra_config == NULL) {
+ return run_session_logic();
+ }
+
+ /* Initialize the memory infrastructure before anything gets allocated
+ */
+ if (infra_config->pceplib_infra_mt != NULL
+ && infra_config->pceplib_messages_mt != NULL) {
+ pceplib_memory_initialize(
+ infra_config->pceplib_infra_mt,
+ infra_config->pceplib_messages_mt,
+ infra_config->malloc_func, infra_config->calloc_func,
+ infra_config->realloc_func, infra_config->strdup_func,
+ infra_config->free_func);
+ }
+
+ if (!run_session_logic_common()) {
+ return false;
+ }
+
+ /* Create the pcep_session_logic pthread so it can be managed externally
+ */
+ if (infra_config->pthread_create_func != NULL) {
+ if (infra_config->pthread_create_func(
+ &(session_logic_handle_->session_logic_thread),
+ NULL, session_logic_loop, session_logic_handle_,
+ "pcep_session_logic")) {
+ pcep_log(
+ LOG_ERR,
+ "%s: Cannot initialize external session_logic thread.",
+ __func__);
+ return false;
+ }
+ } else {
+ if (pthread_create(
+ &(session_logic_handle_->session_logic_thread),
+ NULL, session_logic_loop, session_logic_handle_)) {
+ pcep_log(LOG_ERR,
+ "%s: Cannot initialize session_logic thread.",
+ __func__);
+ return false;
+ }
+ }
+
+ session_logic_event_queue_->event_callback =
+ infra_config->pcep_event_func;
+ session_logic_event_queue_->event_callback_data =
+ infra_config->external_infra_data;
+
+ if (!initialize_timers_external_infra(
+ session_logic_timer_expire_handler,
+ infra_config->external_infra_data,
+ infra_config->timer_create_func,
+ infra_config->timer_cancel_func,
+ infra_config->pthread_create_func)) {
+ pcep_log(
+ LOG_ERR,
+ "%s: Cannot initialize session_logic timers with infra.",
+ __func__);
+ return false;
+ }
+
+ /* We found a problem with the FRR sockets, where not all the KeepAlive
+ * messages were received, so if the pthread_create_func is set, the
+ * internal PCEPlib socket infrastructure will be used. */
+
+ /* For the SocketComm, the socket_read/write_func and the
+ * pthread_create_func are mutually exclusive. */
+ if (infra_config->pthread_create_func != NULL) {
+ if (!initialize_socket_comm_external_infra(
+ infra_config->external_infra_data, NULL, NULL,
+ infra_config->pthread_create_func)) {
+ pcep_log(
+ LOG_ERR,
+ "%s: Cannot initialize session_logic socket comm with infra.",
+ __func__);
+ return false;
+ }
+ } else if (infra_config->socket_read_func != NULL
+ && infra_config->socket_write_func != NULL) {
+ if (!initialize_socket_comm_external_infra(
+ infra_config->external_infra_data,
+ infra_config->socket_read_func,
+ infra_config->socket_write_func, NULL)) {
+ pcep_log(
+ LOG_ERR,
+ "%s: Cannot initialize session_logic socket comm with infra.",
+ __func__);
+ return false;
+ }
+ }
+
+ return true;
+}
+
+bool run_session_logic_wait_for_completion()
+{
+ if (!run_session_logic()) {
+ return false;
+ }
+
+ /* Blocking call, waits for session logic thread to complete */
+ pthread_join(session_logic_handle_->session_logic_thread, NULL);
+
+ return true;
+}
+
+
+bool stop_session_logic()
+{
+ if (session_logic_handle_ == NULL) {
+ pcep_log(LOG_WARNING, "%s: Session logic already stopped",
+ __func__);
+ return false;
+ }
+
+ session_logic_handle_->active = false;
+ teardown_timers();
+
+ pthread_mutex_lock(&(session_logic_handle_->session_logic_mutex));
+ session_logic_handle_->session_logic_condition = true;
+ pthread_cond_signal(&(session_logic_handle_->session_logic_cond_var));
+ pthread_mutex_unlock(&(session_logic_handle_->session_logic_mutex));
+ pthread_join(session_logic_handle_->session_logic_thread, NULL);
+
+ pthread_mutex_destroy(&(session_logic_handle_->session_logic_mutex));
+ pthread_mutex_destroy(&(session_logic_handle_->session_list_mutex));
+ ordered_list_destroy(session_logic_handle_->session_list);
+ queue_destroy(session_logic_handle_->session_event_queue);
+
+ /* destroy the event_queue */
+ pthread_mutex_destroy(&(session_logic_event_queue_->event_queue_mutex));
+ queue_destroy(session_logic_event_queue_->event_queue);
+ pceplib_free(PCEPLIB_INFRA, session_logic_event_queue_);
+
+ /* Explicitly stop the socket comm loop started by the pcep_sessions */
+ destroy_socket_comm_loop();
+
+ pceplib_free(PCEPLIB_INFRA, session_logic_handle_);
+ session_logic_handle_ = NULL;
+
+ return true;
+}
+
+
+void close_pcep_session(pcep_session *session)
+{
+ close_pcep_session_with_reason(session, PCEP_CLOSE_REASON_NO);
+}
+
+void close_pcep_session_with_reason(pcep_session *session,
+ enum pcep_close_reason reason)
+{
+ struct pcep_message *close_msg = pcep_msg_create_close(reason);
+
+ pcep_log(
+ LOG_INFO,
+ "%s: [%ld-%ld] pcep_session_logic send pcep_close message for session [%d]",
+ __func__, time(NULL), pthread_self(), session->session_id);
+
+ session_send_message(session, close_msg);
+ socket_comm_session_close_tcp_after_write(session->socket_comm_session);
+ session->session_state = SESSION_STATE_INITIALIZED;
+}
+
+
+void destroy_pcep_session(pcep_session *session)
+{
+ if (session == NULL) {
+ pcep_log(LOG_WARNING, "%s: Cannot destroy NULL session",
+ __func__);
+ return;
+ }
+
+ /* Remove the session from the session_list and synchronize session
+ * destroy with the session_logic_loop, so that no in-flight events
+ * will be handled now that the session is destroyed. */
+ pthread_mutex_lock(&(session_logic_handle_->session_list_mutex));
+ ordered_list_remove_first_node_equals(
+ session_logic_handle_->session_list, session);
+ pcep_log(LOG_DEBUG,
+ "%s: destroy_pcep_session delete session_list sessionPtr %p",
+ __func__, session);
+
+ pcep_session_cancel_timers(session);
+ delete_counters_group(session->pcep_session_counters);
+ queue_destroy_with_data(session->num_unknown_messages_time_queue);
+ socket_comm_session_teardown(session->socket_comm_session);
+
+ if (session->pcc_config.pcep_msg_versioning != NULL) {
+ pceplib_free(PCEPLIB_INFRA,
+ session->pcc_config.pcep_msg_versioning);
+ }
+
+ if (session->pce_config.pcep_msg_versioning != NULL) {
+ pceplib_free(PCEPLIB_INFRA,
+ session->pce_config.pcep_msg_versioning);
+ }
+
+ int session_id = session->session_id;
+ pceplib_free(PCEPLIB_INFRA, session);
+ pcep_log(LOG_INFO, "%s: [%ld-%ld] session [%d] destroyed", __func__,
+ time(NULL), pthread_self(), session_id);
+ pthread_mutex_unlock(&(session_logic_handle_->session_list_mutex));
+}
+
+void pcep_session_cancel_timers(pcep_session *session)
+{
+ if (session == NULL) {
+ return;
+ }
+
+ if (session->timer_id_dead_timer != TIMER_ID_NOT_SET) {
+ cancel_timer(session->timer_id_dead_timer);
+ }
+
+ if (session->timer_id_keep_alive != TIMER_ID_NOT_SET) {
+ cancel_timer(session->timer_id_keep_alive);
+ }
+
+ if (session->timer_id_open_keep_wait != TIMER_ID_NOT_SET) {
+ cancel_timer(session->timer_id_open_keep_wait);
+ }
+
+ if (session->timer_id_open_keep_alive != TIMER_ID_NOT_SET) {
+ cancel_timer(session->timer_id_open_keep_alive);
+ }
+}
+
+/* Internal util function */
+static int get_next_session_id(void)
+{
+ if (session_id_ == INT_MAX) {
+ session_id_ = 0;
+ }
+
+ return session_id_++;
+}
+
+/* Internal util function */
+static pcep_session *create_pcep_session_pre_setup(pcep_configuration *config)
+{
+ if (config == NULL) {
+ pcep_log(LOG_WARNING,
+ "%s: Cannot create pcep session with NULL config",
+ __func__);
+ return NULL;
+ }
+
+ pcep_session *session =
+ pceplib_malloc(PCEPLIB_INFRA, sizeof(pcep_session));
+ memset(session, 0, sizeof(pcep_session));
+ session->session_id = get_next_session_id();
+ session->session_state = SESSION_STATE_INITIALIZED;
+ session->timer_id_open_keep_wait = TIMER_ID_NOT_SET;
+ session->timer_id_open_keep_alive = TIMER_ID_NOT_SET;
+ session->timer_id_dead_timer = TIMER_ID_NOT_SET;
+ session->timer_id_keep_alive = TIMER_ID_NOT_SET;
+ session->stateful_pce = false;
+ session->num_unknown_messages_time_queue = queue_initialize();
+ session->pce_open_received = false;
+ session->pce_open_rejected = false;
+ session->pce_open_keep_alive_sent = false;
+ session->pcc_open_rejected = false;
+ session->pce_open_accepted = false;
+ session->pcc_open_accepted = false;
+ session->destroy_session_after_write = false;
+ session->lsp_db_version = config->lsp_db_version;
+ memcpy(&(session->pcc_config), config, sizeof(pcep_configuration));
+ /* copy the pcc_config to the pce_config until we receive the open
+ * keep_alive response */
+ memcpy(&(session->pce_config), config, sizeof(pcep_configuration));
+ if (config->pcep_msg_versioning != NULL) {
+ session->pcc_config.pcep_msg_versioning = pceplib_malloc(
+ PCEPLIB_INFRA, sizeof(struct pcep_versioning));
+ memcpy(session->pcc_config.pcep_msg_versioning,
+ config->pcep_msg_versioning,
+ sizeof(struct pcep_versioning));
+ session->pce_config.pcep_msg_versioning = pceplib_malloc(
+ PCEPLIB_INFRA, sizeof(struct pcep_versioning));
+ memcpy(session->pce_config.pcep_msg_versioning,
+ config->pcep_msg_versioning,
+ sizeof(struct pcep_versioning));
+ }
+
+ pthread_mutex_lock(&(session_logic_handle_->session_list_mutex));
+ ordered_list_add_node(session_logic_handle_->session_list, session);
+ pcep_log(
+ LOG_DEBUG,
+ "%s: create_pcep_session_pre_setup add session_list sessionPtr %p",
+ __func__, session);
+ pthread_mutex_unlock(&(session_logic_handle_->session_list_mutex));
+
+ return session;
+}
+
+/* Internal util function */
+static bool create_pcep_session_post_setup(pcep_session *session)
+{
+ if (!socket_comm_session_connect_tcp(session->socket_comm_session)) {
+ pcep_log(LOG_WARNING, "%s: Cannot establish TCP socket.",
+ __func__);
+ destroy_pcep_session(session);
+
+ return false;
+ }
+
+ session->time_connected = time(NULL);
+ create_session_counters(session);
+
+ send_pcep_open(session);
+
+ session->session_state = SESSION_STATE_PCEP_CONNECTING;
+ session->timer_id_open_keep_wait =
+ create_timer(session->pcc_config.keep_alive_seconds, session);
+ // session->session_state = SESSION_STATE_OPENED;
+
+ return true;
+}
+
+pcep_session *create_pcep_session(pcep_configuration *config,
+ struct in_addr *pce_ip)
+{
+ if (pce_ip == NULL) {
+ pcep_log(LOG_WARNING,
+ "%s: Cannot create pcep session with NULL pce_ip",
+ __func__);
+ return NULL;
+ }
+
+ pcep_session *session = create_pcep_session_pre_setup(config);
+ if (session == NULL) {
+ return NULL;
+ }
+
+ session->socket_comm_session = socket_comm_session_initialize_with_src(
+ NULL, session_logic_msg_ready_handler,
+ session_logic_message_sent_handler,
+ session_logic_conn_except_notifier, &(config->src_ip.src_ipv4),
+ ((config->src_pcep_port == 0) ? PCEP_TCP_PORT
+ : config->src_pcep_port),
+ pce_ip,
+ ((config->dst_pcep_port == 0) ? PCEP_TCP_PORT
+ : config->dst_pcep_port),
+ config->socket_connect_timeout_millis,
+ config->tcp_authentication_str, config->is_tcp_auth_md5,
+ session);
+ if (session->socket_comm_session == NULL) {
+ pcep_log(LOG_WARNING,
+ "%s: Cannot establish socket_comm_session.", __func__);
+ destroy_pcep_session(session);
+
+ return NULL;
+ }
+
+ if (create_pcep_session_post_setup(session) == false) {
+ return NULL;
+ }
+
+ return session;
+}
+
+pcep_session *create_pcep_session_ipv6(pcep_configuration *config,
+ struct in6_addr *pce_ip)
+{
+ if (pce_ip == NULL) {
+ pcep_log(LOG_WARNING,
+ "%s: Cannot create pcep session with NULL pce_ip",
+ __func__);
+ return NULL;
+ }
+
+ pcep_session *session = create_pcep_session_pre_setup(config);
+ if (session == NULL) {
+ return NULL;
+ }
+
+ session->socket_comm_session =
+ socket_comm_session_initialize_with_src_ipv6(
+ NULL, session_logic_msg_ready_handler,
+ session_logic_message_sent_handler,
+ session_logic_conn_except_notifier,
+ &(config->src_ip.src_ipv6),
+ ((config->src_pcep_port == 0) ? PCEP_TCP_PORT
+ : config->src_pcep_port),
+ pce_ip,
+ ((config->dst_pcep_port == 0) ? PCEP_TCP_PORT
+ : config->dst_pcep_port),
+ config->socket_connect_timeout_millis,
+ config->tcp_authentication_str, config->is_tcp_auth_md5,
+ session);
+ if (session->socket_comm_session == NULL) {
+ pcep_log(LOG_WARNING,
+ "%s: Cannot establish ipv6 socket_comm_session.",
+ __func__);
+ destroy_pcep_session(session);
+
+ return NULL;
+ }
+
+ if (create_pcep_session_post_setup(session) == false) {
+ return NULL;
+ }
+
+ return session;
+}
+
+
+void session_send_message(pcep_session *session, struct pcep_message *message)
+{
+ pcep_encode_message(message, session->pcc_config.pcep_msg_versioning);
+ socket_comm_session_send_message(session->socket_comm_session,
+ (char *)message->encoded_message,
+ message->encoded_message_length, true);
+
+ increment_message_tx_counters(session, message);
+
+ /* The message->encoded_message will be freed in
+ * socket_comm_session_send_message() once sent.
+ * Setting to NULL here so pcep_msg_free_message() does not free it */
+ message->encoded_message = NULL;
+ pcep_msg_free_message(message);
+}
+
+
+/* This function is also used in pcep_session_logic_states.c */
+struct pcep_message *create_pcep_open(pcep_session *session)
+{
+ /* create and send PCEP open
+ * with PCEP, the PCC sends the config the PCE should use in the open
+ * message,
+ * and the PCE will send an open with the config the PCC should use. */
+ double_linked_list *tlv_list = dll_initialize();
+ if (session->pcc_config.support_stateful_pce_lsp_update
+ || session->pcc_config.support_pce_lsp_instantiation
+ || session->pcc_config.support_include_db_version
+ || session->pcc_config.support_lsp_triggered_resync
+ || session->pcc_config.support_lsp_delta_sync
+ || session->pcc_config.support_pce_triggered_initial_sync) {
+ /* Prepend this TLV as the first in the list */
+ dll_append(
+ tlv_list,
+ pcep_tlv_create_stateful_pce_capability(
+ /* U flag */
+ session->pcc_config
+ .support_stateful_pce_lsp_update,
+ /* S flag */
+ session->pcc_config.support_include_db_version,
+ /* I flag */
+ session->pcc_config
+ .support_pce_lsp_instantiation,
+ /* T flag */
+ session->pcc_config
+ .support_lsp_triggered_resync,
+ /* D flag */
+ session->pcc_config.support_lsp_delta_sync,
+ /* F flag */
+ session->pcc_config
+ .support_pce_triggered_initial_sync));
+ }
+
+ if (session->pcc_config.support_include_db_version) {
+ if (session->pcc_config.lsp_db_version != 0) {
+ dll_append(tlv_list,
+ pcep_tlv_create_lsp_db_version(
+ session->pcc_config.lsp_db_version));
+ }
+ }
+
+ if (session->pcc_config.support_sr_te_pst) {
+ bool flag_n = false;
+ bool flag_x = false;
+ if (session->pcc_config.pcep_msg_versioning
+ ->draft_ietf_pce_segment_routing_07
+ == false) {
+ flag_n = session->pcc_config.pcc_can_resolve_nai_to_sid;
+ flag_x = (session->pcc_config.max_sid_depth == 0);
+ }
+
+ struct pcep_object_tlv_sr_pce_capability *sr_pce_cap_tlv =
+ pcep_tlv_create_sr_pce_capability(
+ flag_n, flag_x,
+ session->pcc_config.max_sid_depth);
+
+ double_linked_list *sub_tlv_list = NULL;
+ if (session->pcc_config.pcep_msg_versioning
+ ->draft_ietf_pce_segment_routing_07
+ == true) {
+ /* With draft07, send the sr_pce_cap_tlv as a normal TLV
+ */
+ dll_append(tlv_list, sr_pce_cap_tlv);
+ } else {
+ /* With draft16, send the sr_pce_cap_tlv as a sub-TLV in
+ * the path_setup_type_capability TLV */
+ sub_tlv_list = dll_initialize();
+ dll_append(sub_tlv_list, sr_pce_cap_tlv);
+ }
+
+ uint8_t *pst =
+ pceplib_malloc(PCEPLIB_MESSAGES, sizeof(uint8_t));
+ *pst = SR_TE_PST;
+ double_linked_list *pst_list = dll_initialize();
+ dll_append(pst_list, pst);
+ dll_append(tlv_list, pcep_tlv_create_path_setup_type_capability(
+ pst_list, sub_tlv_list));
+ }
+
+ struct pcep_message *open_msg = pcep_msg_create_open_with_tlvs(
+ session->pcc_config.keep_alive_seconds,
+ session->pcc_config.dead_timer_seconds, session->session_id,
+ tlv_list);
+
+ pcep_log(
+ LOG_INFO,
+ "%s: [%ld-%ld] pcep_session_logic create open message: TLVs [%d] for session [%d]",
+ __func__, time(NULL), pthread_self(), tlv_list->num_entries,
+ session->session_id);
+
+ return (open_msg);
+}
+
+
+void send_pcep_open(pcep_session *session)
+{
+ session_send_message(session, create_pcep_open(session));
+}
+
+/* This is a blocking call, since it is synchronized with destroy_pcep_session()
+ * and session_logic_loop(). It may be possible that the session has been
+ * deleted but API users havent been informed yet.
+ */
+bool session_exists(pcep_session *session)
+{
+ if (session_logic_handle_ == NULL) {
+ pcep_log(LOG_DEBUG,
+ "%s: session_exists session_logic_handle_ is NULL",
+ __func__);
+ return false;
+ }
+
+ pthread_mutex_lock(&(session_logic_handle_->session_list_mutex));
+ bool retval =
+ (ordered_list_find(session_logic_handle_->session_list, session)
+ != NULL);
+ pthread_mutex_unlock(&(session_logic_handle_->session_list_mutex));
+
+ return retval;
+}