#include "ospfd/ospf_ism.h"
#include "ospfd/ospf_gr_helper.h"
+const char *ospf_exit_reason_desc[] = {
+ "Unknown reason",
+ "Helper inprogress",
+ "Topology Change",
+ "Grace timer expairy",
+ "Successful graceful restart",
+};
+
+const char *ospf_restart_reason_desc[] = {
+ "Unknown restart",
+ "Software restart",
+ "Software reload/upgrade",
+ "Switch to redundant control processor",
+};
+
+const char *ospf_rejected_reason_desc[] = {
+ "Unknown reason",
+ "Helper support disabled",
+ "Neighbour is not in FULL state",
+ "Supports only planned restart but received for unplanned",
+ "Topo change due to change in lsa rxmt list",
+ "LSA age is more than Grace interval",
+};
+
+static bool ospf_check_change_in_rxmt_list(struct ospf_neighbor *nbr);
static unsigned int ospf_enable_rtr_hash_key(const void *data)
{
if (IS_DEBUG_OSPF_GR_HELPER)
zlog_debug("%s, GR Helper init.", __PRETTY_FUNCTION__);
- ospf->is_helper_supported = OSPF_FALSE;
- ospf->strict_lsa_check = OSPF_TRUE;
- ospf->only_planned_restart = OSPF_FALSE;
+ ospf->is_helper_supported = OSPF_GR_FALSE;
+ ospf->strict_lsa_check = OSPF_GR_TRUE;
+ ospf->only_planned_restart = OSPF_GR_FALSE;
ospf->supported_grace_time = OSPF_MAX_GRACE_INTERVAL;
ospf->last_exit_reason = OSPF_GR_HELPER_EXIT_NONE;
ospf->active_restarter_cnt = 0;
ospf_enable_rtr_hash_destroy(ospf);
}
+
+/*
+ * Extracting tlv info from GRACE LSA.
+ *
+ * lsa
+ * ospf grace lsa
+ *
+ * Returns:
+ * interval : grace interval.
+ * addr : RESTARTER address.
+ * reason : Restarting reason.
+ */
+static int ospf_extract_grace_lsa_fields(struct ospf_lsa *lsa,
+ uint32_t *interval,
+ struct in_addr *addr, uint8_t *reason)
+{
+ struct lsa_header *lsah = NULL;
+ struct tlv_header *tlvh = NULL;
+ struct grace_tlv_graceperiod *grace_period;
+ struct grace_tlv_restart_reason *gr_reason;
+ struct grace_tlv_restart_addr *restart_addr;
+ uint16_t length = 0;
+ int sum = 0;
+
+ lsah = (struct lsa_header *)lsa->data;
+
+ length = ntohs(lsah->length) - OSPF_LSA_HEADER_SIZE;
+
+ for (tlvh = TLV_HDR_TOP(lsah); sum < length;
+ tlvh = TLV_HDR_NEXT(tlvh)) {
+ switch (ntohs(tlvh->type)) {
+ case GRACE_PERIOD_TYPE:
+ grace_period = (struct grace_tlv_graceperiod *)tlvh;
+ *interval = ntohl(grace_period->interval);
+ sum += TLV_SIZE(tlvh);
+
+ /* Check if grace interval is valid */
+ if (*interval > OSPF_MAX_GRACE_INTERVAL
+ || *interval < OSPF_MIN_GRACE_INTERVAL)
+ return OSPF_GR_FAILURE;
+ break;
+ case RESTART_REASON_TYPE:
+ gr_reason = (struct grace_tlv_restart_reason *)tlvh;
+ *reason = gr_reason->reason;
+ sum += TLV_SIZE(tlvh);
+
+ if (*reason >= OSPF_GR_INVALID_REASON_CODE)
+ return OSPF_GR_FAILURE;
+ break;
+ case RESTARTER_IP_ADDR_TYPE:
+ restart_addr = (struct grace_tlv_restart_addr *)tlvh;
+ addr->s_addr = restart_addr->addr.s_addr;
+ sum += TLV_SIZE(tlvh);
+ break;
+ default:
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Malformed packet.Invalid TLV type:%d",
+ __PRETTY_FUNCTION__, ntohs(tlvh->type));
+ return OSPF_GR_FAILURE;
+ }
+ }
+
+ return OSPF_GR_SUCCESS;
+}
+
+/*
+ * Grace timer expiry handler.
+ * HELPER aborts its role at grace timer expiry.
+ *
+ * thread
+ * thread pointer
+ *
+ * Returns:
+ * Nothing
+ */
+static int ospf_handle_grace_timer_expiry(struct thread *thread)
+{
+ struct ospf_neighbor *nbr = THREAD_ARG(thread);
+
+ nbr->gr_helper_info.t_grace_timer = NULL;
+
+ ospf_gr_helper_exit(nbr, OSPF_GR_HELPER_GRACE_TIMEOUT);
+ return OSPF_GR_SUCCESS;
+}
+
+/*
+ * Process Grace LSA.If it is eligible move to HELPER role.
+ * Ref rfc3623 section 3.1
+ *
+ * ospf
+ * Ospf pointer.
+ *
+ * lsa
+ * Grace LSA received from RESTARTER.
+ *
+ * nbr
+ * ospf neighbour which requets the router to act as
+ * HELPER.
+ *
+ * Returns:
+ * status.
+ * If supported as HELPER : OSPF_GR_HELPER_INPROGRESS
+ * If Not supported as HELPER : OSPF_GR_HELPER_NONE
+ */
+int ospf_process_grace_lsa(struct ospf *ospf, struct ospf_lsa *lsa,
+ struct ospf_neighbor *nbr)
+{
+ struct in_addr restart_addr = {0};
+ uint8_t restart_reason = 0;
+ uint32_t grace_interval = 0;
+ uint32_t actual_grace_interval = 0;
+ struct advRtr lookup;
+ struct ospf_neighbor *restarter = NULL;
+ struct ospf_interface *oi = nbr->oi;
+ int ret;
+
+
+ /* Extract the grace lsa packet fields */
+ ret = ospf_extract_grace_lsa_fields(lsa, &grace_interval, &restart_addr,
+ &restart_reason);
+ if (ret != OSPF_GR_SUCCESS) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug("%s, Wrong Grace LSA packet.",
+ __PRETTY_FUNCTION__);
+ return OSPF_GR_NOT_HELPER;
+ }
+
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Grace LSA received from %s, grace interval:%u, restartreason :%s",
+ __PRETTY_FUNCTION__, inet_ntoa(restart_addr),
+ grace_interval, ospf_restart_reason_desc[restart_reason]);
+
+ /* Incase of broadcast links, if RESTARTER is DR_OTHER,
+ * grace LSA might be received from DR, so need to get
+ * actual neighbour info , here RESTARTER.
+ */
+ if (oi->type != OSPF_IFTYPE_POINTOPOINT) {
+ restarter = ospf_nbr_lookup_by_addr(oi->nbrs, &restart_addr);
+
+ if (!restarter) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Restarter is not a nbr(%s) for this router.",
+ __PRETTY_FUNCTION__,
+ inet_ntoa(restart_addr));
+ return OSPF_GR_NOT_HELPER;
+ }
+ } else
+ restarter = nbr;
+
+ /* Verify Helper enabled globally */
+ if (!ospf->is_helper_supported) {
+ /* Verify that Helper support is enabled for the
+ * current neighbour router-id.
+ */
+ lookup.advRtrAddr.s_addr = restarter->router_id.s_addr;
+
+ if (!hash_lookup(ospf->enable_rtr_list, &lookup)) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, HELPER support is disabled, So not a HELPER",
+ __PRETTY_FUNCTION__);
+ restarter->gr_helper_info.rejected_reason =
+ OSPF_HELPER_SUPPORT_DISABLED;
+ return OSPF_GR_NOT_HELPER;
+ }
+ }
+
+
+ /* Check neighbour is in FULL state and
+ * became a adjacency.
+ */
+ if (!IS_NBR_STATE_FULL(restarter)) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, This Neighbour %s is not in FULL state.",
+ __PRETTY_FUNCTION__, inet_ntoa(restarter->src));
+ restarter->gr_helper_info.rejected_reason =
+ OSPF_HELPER_NOT_A_VALID_NEIGHBOUR;
+ return OSPF_GR_NOT_HELPER;
+ }
+
+ /* Based on the restart reason from grace lsa
+ * check the current router is supporting or not
+ */
+ if (ospf->only_planned_restart
+ && !OSPF_GR_IS_PLANNED_RESTART(restart_reason)) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Router supports only planned restarts but received the GRACE LSA for an unplanned restart.",
+ __PRETTY_FUNCTION__);
+ restarter->gr_helper_info.rejected_reason =
+ OSPF_HELPER_PLANNED_ONLY_RESTART;
+ return OSPF_GR_NOT_HELPER;
+ }
+
+ /* Check the retranmission list of this
+ * neighbour, check any change in lsas.
+ */
+ if (ospf->strict_lsa_check && !ospf_ls_retransmit_isempty(restarter)
+ && ospf_check_change_in_rxmt_list(restarter)) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Changed LSA in Rxmt list. So not Helper.",
+ __PRETTY_FUNCTION__);
+ restarter->gr_helper_info.rejected_reason =
+ OSPF_HELPER_TOPO_CHANGE_RTXMT_LIST;
+ return OSPF_GR_NOT_HELPER;
+ }
+
+ /*LSA age must be less than the grace period */
+ if (ntohs(lsa->data->ls_age) >= grace_interval) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Grace LSA age(%d) is more than the graceinterval(%d)",
+ __PRETTY_FUNCTION__, lsa->data->ls_age,
+ grace_interval);
+ restarter->gr_helper_info.rejected_reason =
+ OSPF_HELPER_LSA_AGE_MORE;
+ return OSPF_GR_NOT_HELPER;
+ }
+
+ /* check supported grace period configured
+ * if configured, use this to start the grace
+ * timer otherwise use the interval received
+ * in grace LSA packet.
+ */
+ actual_grace_interval = grace_interval;
+ if (grace_interval > ospf->supported_grace_time) {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Received grace period %d is larger than supported grace %d",
+ __PRETTY_FUNCTION__, grace_interval,
+ ospf->supported_grace_time);
+ actual_grace_interval = ospf->supported_grace_time;
+ }
+
+ if (OSPF_GR_IS_ACTIVE_HELPER(restarter)) {
+ if (restarter->gr_helper_info.t_grace_timer)
+ THREAD_OFF(restarter->gr_helper_info.t_grace_timer);
+
+ if (ospf->active_restarter_cnt > 0)
+ ospf->active_restarter_cnt--;
+
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, Router is already acting as a HELPER for this nbr,so restart the grace timer",
+ __PRETTY_FUNCTION__);
+ } else {
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug(
+ "%s, This Router becomes a HELPER for the neighbour %s",
+ __PRETTY_FUNCTION__, inet_ntoa(restarter->src));
+ }
+
+ /* Became a Helper to the RESTART neighbour.
+ * Change the helper status.
+ */
+ restarter->gr_helper_info.gr_helper_status = OSPF_GR_ACTIVE_HELPER;
+ restarter->gr_helper_info.recvd_grace_period = grace_interval;
+ restarter->gr_helper_info.actual_grace_period = actual_grace_interval;
+ restarter->gr_helper_info.gr_restart_reason = restart_reason;
+ restarter->gr_helper_info.rejected_reason = OSPF_HELPER_REJECTED_NONE;
+
+ /* Incremnet the active restarer count */
+ ospf->active_restarter_cnt++;
+
+ if (IS_DEBUG_OSPF_GR_HELPER)
+ zlog_debug("%s, Grace timer started.interval:%d",
+ __PRETTY_FUNCTION__, actual_grace_interval);
+
+ /* Start the grace timer */
+ thread_add_timer(master, ospf_handle_grace_timer_expiry, restarter,
+ actual_grace_interval,
+ &restarter->gr_helper_info.t_grace_timer);
+
+ return OSPF_GR_ACTIVE_HELPER;
+}
+
+/*
+ * API to check any change in the neighbor's
+ * retransmission list.
+ *
+ * nbr
+ * ospf neighbor
+ *
+ * Returns:
+ * TRUE - if any change in the lsa.
+ * FALSE - no change in the lsas.
+ */
+static bool ospf_check_change_in_rxmt_list(struct ospf_neighbor *nbr)
+{
+ struct route_node *rn;
+ struct ospf_lsa *lsa;
+ struct route_table *tbl;
+
+ tbl = nbr->ls_rxmt.type[OSPF_ROUTER_LSA].db;
+ LSDB_LOOP (tbl, rn, lsa)
+ if (lsa->to_be_acknowledged)
+ return OSPF_GR_TRUE;
+ tbl = nbr->ls_rxmt.type[OSPF_NETWORK_LSA].db;
+ LSDB_LOOP (tbl, rn, lsa)
+ if (lsa->to_be_acknowledged)
+ return OSPF_GR_TRUE;
+
+ tbl = nbr->ls_rxmt.type[OSPF_SUMMARY_LSA].db;
+ LSDB_LOOP (tbl, rn, lsa)
+ if (lsa->to_be_acknowledged)
+ return OSPF_GR_TRUE;
+
+ tbl = nbr->ls_rxmt.type[OSPF_ASBR_SUMMARY_LSA].db;
+ LSDB_LOOP (tbl, rn, lsa)
+ if (lsa->to_be_acknowledged)
+ return OSPF_GR_TRUE;
+
+ tbl = nbr->ls_rxmt.type[OSPF_AS_EXTERNAL_LSA].db;
+ LSDB_LOOP (tbl, rn, lsa)
+ if (lsa->to_be_acknowledged)
+ return OSPF_GR_TRUE;
+
+ tbl = nbr->ls_rxmt.type[OSPF_AS_NSSA_LSA].db;
+ LSDB_LOOP (tbl, rn, lsa)
+ if (lsa->to_be_acknowledged)
+ return OSPF_GR_TRUE;
+
+ return OSPF_GR_FALSE;
+}
+
+/*
+ * Api to exit from HELPER role to take all actions
+ * required at exit.
+ * Ref rfc3623 section 3.2
+ *
+ * ospf
+ * Ospf pointer.
+ *
+ * nbr
+ * Ospf neighbour for which it is acting as HELPER.
+ *
+ * reason
+ * The reason for exiting from HELPER.
+ *
+ * Returns:
+ * Nothing.
+ */
+void ospf_gr_helper_exit(struct ospf_neighbor *nbr,
+ enum ospf_helper_exit_reason reason)
+{
+ return;
+}
+
+/*
+ * Process Maxage Grace LSA.
+ * It is a indication for successfull completion of GR.
+ * If router acting as HELPER, It exits from helper role.
+ *
+ * ospf
+ * Ospf pointer.
+ *
+ * lsa
+ * Grace LSA received from RESTARTER.
+ *
+ * nbr
+ * ospf neighbour which requets the router to act as
+ * HELPER.
+ *
+ * Returns:
+ * Nothing.
+ */
+void ospf_process_maxage_grace_lsa(struct ospf *ospf, struct ospf_lsa *lsa,
+ struct ospf_neighbor *nbr)
+{
+ return;
+}
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