Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1952 insertions, 0 deletions

diff --git a/ospfd/ospf_ext.c b/ospfd/ospf_ext.c
new file mode 100644
index 0000000..75b5803
--- /dev/null
+++ b/ospfd/ospf_ext.c
@@ -0,0 +1,1952 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * This is an implementation of RFC7684 OSPFv2 Prefix/Link Attribute
+ * Advertisement
+ *
+ * Module name: Extended Prefix/Link Opaque LSA
+ *
+ * Author: Olivier Dugeon <olivier.dugeon@orange.com>
+ * Author: Anselme Sawadogo <anselmesawadogo@gmail.com>
+ *
+ * Copyright (C) 2016 - 2018 Orange Labs http://www.orange.com
+ */
+
+#include <zebra.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "linklist.h"
+#include "prefix.h"
+#include "if.h"
+#include "table.h"
+#include "memory.h"
+#include "command.h"
+#include "vty.h"
+#include "stream.h"
+#include "log.h"
+#include "frrevent.h"
+#include "hash.h"
+#include "sockunion.h" /* for inet_aton() */
+#include "network.h"
+#include "if.h"
+#include "libospf.h" /* for ospf interface types */
+
+#include "ospfd/ospfd.h"
+#include "ospfd/ospf_interface.h"
+#include "ospfd/ospf_ism.h"
+#include "ospfd/ospf_asbr.h"
+#include "ospfd/ospf_lsa.h"
+#include "ospfd/ospf_lsdb.h"
+#include "ospfd/ospf_neighbor.h"
+#include "ospfd/ospf_nsm.h"
+#include "ospfd/ospf_flood.h"
+#include "ospfd/ospf_packet.h"
+#include "ospfd/ospf_spf.h"
+#include "ospfd/ospf_dump.h"
+#include "ospfd/ospf_route.h"
+#include "ospfd/ospf_ase.h"
+#include "ospfd/ospf_zebra.h"
+#include "ospfd/ospf_sr.h"
+#include "ospfd/ospf_ext.h"
+#include "ospfd/ospf_errors.h"
+
+/* Following structure are internal use only. */
+
+/*
+ * Global variable to manage Extended Prefix/Link Opaque LSA on this node.
+ * Note that all parameter values are stored in network byte order.
+ */
+static struct ospf_ext_lp OspfEXT;
+
+/*
+ * -----------------------------------------------------------------------
+ * Following are initialize/terminate functions for Extended Prefix/Link
+ * Opaque LSA handling.
+ * -----------------------------------------------------------------------
+ */
+
+/* Extended Prefix Opaque LSA related callback functions */
+static void ospf_ext_pref_show_info(struct vty *vty, struct json_object *json,
+				    struct ospf_lsa *lsa);
+static int ospf_ext_pref_lsa_originate(void *arg);
+static struct ospf_lsa *ospf_ext_pref_lsa_refresh(struct ospf_lsa *lsa);
+static void ospf_ext_pref_lsa_schedule(struct ext_itf *exti,
+				       enum lsa_opcode opcode);
+/* Extended Link Opaque LSA related callback functions */
+static int ospf_ext_link_new_if(struct interface *ifp);
+static int ospf_ext_link_del_if(struct interface *ifp);
+static void ospf_ext_ism_change(struct ospf_interface *oi, int old_status);
+static void ospf_ext_link_nsm_change(struct ospf_neighbor *nbr, int old_status);
+static void ospf_ext_link_show_info(struct vty *vty, struct json_object *json,
+				    struct ospf_lsa *lsa);
+static int ospf_ext_link_lsa_originate(void *arg);
+static struct ospf_lsa *ospf_ext_link_lsa_refresh(struct ospf_lsa *lsa);
+static void ospf_ext_link_lsa_schedule(struct ext_itf *exti,
+				       enum lsa_opcode opcode);
+static void ospf_ext_lsa_schedule(struct ext_itf *exti, enum lsa_opcode op);
+static int ospf_ext_link_lsa_update(struct ospf_lsa *lsa);
+static int ospf_ext_pref_lsa_update(struct ospf_lsa *lsa);
+static void ospf_ext_link_delete_adj_sid(struct ext_itf *exti);
+static void del_ext_info(void *val);
+
+/*
+ * Extended Link/Prefix initialization
+ *
+ * @param - none
+ *
+ * @return - 0 if OK, <> 0 otherwise
+ */
+int ospf_ext_init(void)
+{
+	int rc = 0;
+
+	memset(&OspfEXT, 0, sizeof(OspfEXT));
+	OspfEXT.enabled = false;
+	/* Only Area flooding is supported yet */
+	OspfEXT.scope = OSPF_OPAQUE_AREA_LSA;
+	/* Initialize interface list */
+	OspfEXT.iflist = list_new();
+	OspfEXT.iflist->del = del_ext_info;
+
+	zlog_info("EXT (%s): Register Extended Link Opaque LSA", __func__);
+	rc = ospf_register_opaque_functab(
+		OSPF_OPAQUE_AREA_LSA, OPAQUE_TYPE_EXTENDED_LINK_LSA,
+		ospf_ext_link_new_if,	/* new if */
+		ospf_ext_link_del_if,	/* del if */
+		ospf_ext_ism_change,	/* ism change */
+		ospf_ext_link_nsm_change,    /* nsm change */
+		NULL,			     /* Write router config. */
+		NULL,			     /* Write interface conf. */
+		NULL,			     /* Write debug config. */
+		ospf_ext_link_show_info,     /* Show LSA info */
+		ospf_ext_link_lsa_originate, /* Originate LSA */
+		ospf_ext_link_lsa_refresh,   /* Refresh LSA */
+		ospf_ext_link_lsa_update,    /* new_lsa_hook */
+		NULL);			     /* del_lsa_hook */
+
+	if (rc != 0) {
+		flog_warn(EC_OSPF_OPAQUE_REGISTRATION,
+			  "EXT (%s): Failed to register Extended Link LSA",
+			  __func__);
+		return rc;
+	}
+
+	zlog_info("EXT (%s): Register Extended Prefix Opaque LSA", __func__);
+	rc = ospf_register_opaque_functab(
+		OspfEXT.scope, OPAQUE_TYPE_EXTENDED_PREFIX_LSA,
+		NULL,			     /* new if handle by link */
+		NULL,			     /* del if handle by link */
+		NULL,			     /* ism change */
+		NULL,			     /* nsm change */
+		ospf_sr_config_write_router, /* Write router config. */
+		NULL,			     /* Write interface conf. */
+		NULL,			     /* Write debug config. */
+		ospf_ext_pref_show_info,     /* Show LSA info */
+		ospf_ext_pref_lsa_originate, /* Originate LSA */
+		ospf_ext_pref_lsa_refresh,   /* Refresh LSA */
+		ospf_ext_pref_lsa_update,    /* new_lsa_hook */
+		NULL);			     /* del_lsa_hook */
+	if (rc != 0) {
+		flog_warn(EC_OSPF_OPAQUE_REGISTRATION,
+			  "EXT (%s): Failed to register Extended Prefix LSA",
+			  __func__);
+		return rc;
+	}
+
+	return rc;
+}
+
+/*
+ * Extended Link/Prefix termination function
+ *
+ * @param - none
+ * @return - none
+ */
+void ospf_ext_term(void)
+{
+
+	if ((OspfEXT.scope == OSPF_OPAQUE_AREA_LSA)
+	    || (OspfEXT.scope == OSPF_OPAQUE_AS_LSA))
+		ospf_delete_opaque_functab(OspfEXT.scope,
+					   OPAQUE_TYPE_EXTENDED_PREFIX_LSA);
+
+	ospf_delete_opaque_functab(OSPF_OPAQUE_AREA_LSA,
+				   OPAQUE_TYPE_EXTENDED_LINK_LSA);
+
+	list_delete(&OspfEXT.iflist);
+	OspfEXT.scope = 0;
+	OspfEXT.enabled = false;
+
+	return;
+}
+
+/*
+ * Extended Link/Prefix finish function
+ *
+ * @param - none
+ * @return - none
+ */
+void ospf_ext_finish(void)
+{
+
+	struct listnode *node;
+	struct ext_itf *exti;
+
+	/* Flush Router Info LSA */
+	for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti))
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+			ospf_ext_lsa_schedule(exti, FLUSH_THIS_LSA);
+
+	OspfEXT.enabled = false;
+}
+
+/*
+ * ---------------------------------------------------------------------
+ * Following are control functions for Extended Prefix/Link Opaque LSA
+ * parameters management.
+ * ---------------------------------------------------------------------
+ */
+
+/* Functions to free memory space */
+static void del_ext_info(void *val)
+{
+	XFREE(MTYPE_OSPF_EXT_PARAMS, val);
+}
+
+/* Increment instance value for Extended Prefix Opaque LSAs Opaque ID field */
+static uint32_t get_ext_pref_instance_value(void)
+{
+	static uint32_t seqno = 0;
+
+	if (seqno < MAX_LEGAL_EXT_INSTANCE_NUM)
+		seqno += 1;
+	else
+		seqno = 1; /* Avoid zero. */
+
+	return seqno;
+}
+
+/* Increment instance value for Extended Link Opaque LSAs Opaque ID field */
+static uint32_t get_ext_link_instance_value(void)
+{
+	static uint32_t seqno = 0;
+
+	if (seqno < MAX_LEGAL_EXT_INSTANCE_NUM)
+		seqno += 1;
+	else
+		seqno = 1; /* Avoid zero. */
+
+	return seqno;
+}
+
+/* Lookup Extended Prefix/Links by ifp from OspfEXT struct iflist */
+static struct ext_itf *lookup_ext_by_ifp(struct interface *ifp)
+{
+	struct listnode *node;
+	struct ext_itf *exti;
+
+	for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti))
+		if (exti->ifp == ifp)
+			return exti;
+
+	return NULL;
+}
+
+/* Lookup Extended Prefix/Links by LSA ID from OspfEXT struct iflist */
+static struct ext_itf *lookup_ext_by_instance(struct ospf_lsa *lsa)
+{
+	struct listnode *node;
+	struct ext_itf *exti;
+	uint32_t key = GET_OPAQUE_ID(ntohl(lsa->data->id.s_addr));
+	uint8_t type = GET_OPAQUE_TYPE(ntohl(lsa->data->id.s_addr));
+
+
+	for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti))
+		if ((exti->instance == key) && (exti->type == type))
+			return exti;
+
+	return NULL;
+}
+
+/*
+ * ----------------------------------------------------------------------
+ * The underlying subsection defines setters and unsetters to create and
+ * delete tlvs and subtlvs
+ * ----------------------------------------------------------------------
+ */
+
+/* Extended Prefix TLV - RFC7684 section 2.1 */
+static void set_ext_prefix(struct ext_itf *exti, uint8_t route_type,
+			   uint8_t flags, struct prefix_ipv4 p)
+{
+
+	TLV_TYPE(exti->prefix) = htons(EXT_TLV_PREFIX);
+	/* Warning: Size must be adjust depending of subTLV's */
+	TLV_LEN(exti->prefix) = htons(EXT_TLV_PREFIX_SIZE);
+	exti->prefix.route_type = route_type;
+	exti->prefix.flags = flags;
+	/* Only Address Family Ipv4 (0) is defined in RFC 7684 */
+	exti->prefix.af = 0;
+	exti->prefix.pref_length = p.prefixlen;
+	exti->prefix.address = p.prefix;
+
+	SET_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE);
+}
+
+/* Extended Link TLV - RFC7684 section 3.1 */
+static void set_ext_link(struct ext_itf *exti, uint8_t type, struct in_addr id,
+			 struct in_addr data)
+{
+
+	TLV_TYPE(exti->link) = htons(EXT_TLV_LINK);
+	/* Warning: Size must be adjust depending of subTLV's */
+	TLV_LEN(exti->link) = htons(EXT_TLV_LINK_SIZE);
+	exti->link.link_type = type;
+	exti->link.link_id = id;
+	exti->link.link_data = data;
+}
+
+/* Prefix SID SubTLV - section 5 */
+static void set_prefix_sid(struct ext_itf *exti, uint8_t algorithm,
+			   uint32_t value, int value_type, uint8_t flags)
+{
+
+	if ((algorithm != SR_ALGORITHM_SPF)
+	    && (algorithm != SR_ALGORITHM_STRICT_SPF)) {
+		flog_err(EC_OSPF_INVALID_ALGORITHM,
+			 "EXT (%s): unrecognized algorithm, not SPF or S-SPF",
+			 __func__);
+		return;
+	}
+
+	/* Update flags according to the type of value field: label or index */
+	if (value_type == SID_LABEL)
+		SET_FLAG(flags, EXT_SUBTLV_PREFIX_SID_VFLG);
+
+	/* set prefix sid subtlv for an extended prefix tlv */
+	TLV_TYPE(exti->node_sid) = htons(EXT_SUBTLV_PREFIX_SID);
+	exti->node_sid.algorithm = algorithm;
+	exti->node_sid.flags = flags;
+	exti->node_sid.mtid = 0; /* Multi-Topology is not supported */
+
+	/* Set Label or Index value */
+	if (value_type == SID_LABEL) {
+		TLV_LEN(exti->node_sid) =
+			htons(SID_LABEL_SIZE(EXT_SUBTLV_PREFIX_SID_SIZE));
+		exti->node_sid.value = htonl(SET_LABEL(value));
+	} else {
+		TLV_LEN(exti->node_sid) =
+			htons(SID_INDEX_SIZE(EXT_SUBTLV_PREFIX_SID_SIZE));
+		exti->node_sid.value = htonl(value);
+	}
+}
+
+/* Adjacency SID SubTLV - section 6.1 */
+static void set_adj_sid(struct ext_itf *exti, bool backup, uint32_t value,
+			int value_type)
+{
+	int index;
+	uint8_t flags;
+
+	/* Determine which ADJ_SID must be set: nominal or backup */
+	if (backup) {
+		flags = EXT_SUBTLV_LINK_ADJ_SID_BFLG;
+		index = 1;
+	} else {
+		index = 0;
+		flags = 0;
+	}
+
+	/* Set Header */
+	TLV_TYPE(exti->adj_sid[index]) = htons(EXT_SUBTLV_ADJ_SID);
+
+	/* Only Local ADJ-SID is supported for the moment */
+	SET_FLAG(flags, EXT_SUBTLV_LINK_ADJ_SID_LFLG);
+
+	exti->adj_sid[index].mtid = 0; /* Multi-Topology is not supported */
+
+	/* Adjust Length, Flags and Value depending on the type of Label */
+	if (value_type == SID_LABEL) {
+		SET_FLAG(flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG);
+		TLV_LEN(exti->adj_sid[index]) =
+			htons(SID_LABEL_SIZE(EXT_SUBTLV_ADJ_SID_SIZE));
+		exti->adj_sid[index].value = htonl(SET_LABEL(value));
+	} else {
+		UNSET_FLAG(flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG);
+		TLV_LEN(exti->adj_sid[index]) =
+			htons(SID_INDEX_SIZE(EXT_SUBTLV_ADJ_SID_SIZE));
+		exti->adj_sid[index].value = htonl(value);
+	}
+
+	exti->adj_sid[index].flags = flags; /* Set computed flags */
+	exti->adj_sid[index].mtid = 0;   /* Multi-Topology is not supported */
+	exti->adj_sid[index].weight = 0; /* Load-Balancing is not supported */
+}
+
+/* LAN Adjacency SID SubTLV - section 6.2 */
+static void set_lan_adj_sid(struct ext_itf *exti, bool backup, uint32_t value,
+			    int value_type, struct in_addr neighbor_id)
+{
+
+	int index;
+	uint8_t flags;
+
+	/* Determine which ADJ_SID must be set: nominal or backup */
+	if (backup) {
+		flags = EXT_SUBTLV_LINK_ADJ_SID_BFLG;
+		index = 1;
+	} else {
+		index = 0;
+		flags = 0;
+	}
+
+	/* Set Header */
+	TLV_TYPE(exti->lan_sid[index]) = htons(EXT_SUBTLV_LAN_ADJ_SID);
+
+	/* Only Local ADJ-SID is supported for the moment */
+	SET_FLAG(flags, EXT_SUBTLV_LINK_ADJ_SID_LFLG);
+
+	/* Adjust Length, Flags and Value depending on the type of Label */
+	if (value_type == SID_LABEL) {
+		SET_FLAG(flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG);
+		TLV_LEN(exti->lan_sid[index]) =
+			htons(SID_LABEL_SIZE(EXT_SUBTLV_PREFIX_RANGE_SIZE));
+		exti->lan_sid[index].value = htonl(SET_LABEL(value));
+	} else {
+		UNSET_FLAG(flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG);
+		TLV_LEN(exti->lan_sid[index]) =
+			htons(SID_INDEX_SIZE(EXT_SUBTLV_PREFIX_RANGE_SIZE));
+		exti->lan_sid[index].value = htonl(value);
+	}
+
+	exti->lan_sid[index].flags = flags; /* Set computed flags */
+	exti->lan_sid[index].mtid = 0;   /* Multi-Topology is not supported */
+	exti->lan_sid[index].weight = 0; /* Load-Balancing is not supported */
+	exti->lan_sid[index].neighbor_id = neighbor_id;
+}
+
+static void unset_adjacency_sid(struct ext_itf *exti)
+{
+	/* Reset Adjacency TLV */
+	if (exti->type == ADJ_SID) {
+		TLV_TYPE(exti->adj_sid[0]) = 0;
+		TLV_TYPE(exti->adj_sid[1]) = 0;
+	}
+	/* or Lan-Adjacency TLV */
+	if (exti->type == LAN_ADJ_SID) {
+		TLV_TYPE(exti->lan_sid[0]) = 0;
+		TLV_TYPE(exti->lan_sid[1]) = 0;
+	}
+}
+
+/* Experimental SubTLV from Cisco */
+static void set_rmt_itf_addr(struct ext_itf *exti, struct in_addr rmtif)
+{
+
+	TLV_TYPE(exti->rmt_itf_addr) = htons(EXT_SUBTLV_RMT_ITF_ADDR);
+	TLV_LEN(exti->rmt_itf_addr) = htons(sizeof(struct in_addr));
+	exti->rmt_itf_addr.value = rmtif;
+}
+
+/* Delete Extended LSA */
+static void ospf_extended_lsa_delete(struct ext_itf *exti)
+{
+
+	/* Avoid deleting LSA if Extended is not enable */
+	if (!OspfEXT.enabled)
+		return;
+
+	/* Process only Active Extended Prefix/Link LSA */
+	if (!CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE))
+		return;
+
+	osr_debug("EXT (%s): Disable %s%s%s-SID on interface %s", __func__,
+		  exti->stype == LOCAL_SID ? "Prefix" : "",
+		  exti->stype == ADJ_SID ? "Adjacency" : "",
+		  exti->stype == LAN_ADJ_SID ? "LAN-Adjacency" : "",
+		  exti->ifp->name);
+
+	/* Flush LSA if already engaged */
+	if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED)) {
+		ospf_ext_lsa_schedule(exti, FLUSH_THIS_LSA);
+		UNSET_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED);
+	}
+
+	/* De-activate this Extended Prefix/Link and remove corresponding
+	 * Segment-Routing Prefix-SID or (LAN)-ADJ-SID */
+	if (exti->stype == ADJ_SID || exti->stype == LAN_ADJ_SID)
+		ospf_ext_link_delete_adj_sid(exti);
+	else
+		ospf_sr_ext_itf_delete(exti);
+}
+
+/*
+ * Update Extended prefix SID index for Loopback interface type
+ *
+ * @param ifname - Loopback interface name
+ * @param index - new value for the prefix SID of this interface
+ * @param p - prefix for this interface or NULL if Extended Prefix
+ * should be remove
+ *
+ * @return instance number if update is OK, 0 otherwise
+ */
+uint32_t ospf_ext_schedule_prefix_index(struct interface *ifp, uint32_t index,
+					struct prefix_ipv4 *p, uint8_t flags)
+{
+	int rc = 0;
+	struct ext_itf *exti;
+
+	/* Find Extended Prefix interface */
+	exti = lookup_ext_by_ifp(ifp);
+	if (exti == NULL)
+		return rc;
+
+	if (p != NULL) {
+		osr_debug("EXT (%s): Schedule new prefix %pFX with index %u on interface %s", __func__, p, index, ifp->name);
+
+		/* Set first Extended Prefix then the Prefix SID information */
+		set_ext_prefix(exti, OSPF_PATH_INTRA_AREA, EXT_TLV_PREF_NFLG,
+			       *p);
+		set_prefix_sid(exti, SR_ALGORITHM_SPF, index, SID_INDEX, flags);
+
+		/* Try to Schedule LSA */
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE)) {
+			if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+				ospf_ext_pref_lsa_schedule(exti,
+							   REFRESH_THIS_LSA);
+			else
+				ospf_ext_pref_lsa_schedule(
+					exti, REORIGINATE_THIS_LSA);
+		}
+	} else {
+		osr_debug("EXT (%s): Remove prefix for interface %s", __func__,
+			  ifp->name);
+
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+			ospf_ext_pref_lsa_schedule(exti, FLUSH_THIS_LSA);
+	}
+
+	return SET_OPAQUE_LSID(exti->type, exti->instance);
+}
+
+/**
+ * Update Adjacecny-SID for Extended Link LSA
+ *
+ * @param exti	Extended Link information
+ */
+static void ospf_ext_link_update_adj_sid(struct ext_itf *exti)
+{
+	mpls_label_t label;
+	mpls_label_t bck_label;
+
+	/* Process only (LAN)Adjacency-SID Type */
+	if (exti->stype != ADJ_SID && exti->stype != LAN_ADJ_SID)
+		return;
+
+	/* Request Primary & Backup Labels from Label Manager */
+	bck_label = ospf_sr_local_block_request_label();
+	label = ospf_sr_local_block_request_label();
+	if (bck_label == MPLS_INVALID_LABEL || label == MPLS_INVALID_LABEL) {
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+			ospf_ext_lsa_schedule(exti, FLUSH_THIS_LSA);
+		return;
+	}
+
+	/* Set Adjacency-SID, backup first */
+	if (exti->stype == ADJ_SID) {
+		set_adj_sid(exti, true, bck_label, SID_LABEL);
+		set_adj_sid(exti, false, label, SID_LABEL);
+	} else {
+		set_lan_adj_sid(exti, true, bck_label, SID_LABEL,
+				exti->lan_sid[0].neighbor_id);
+		set_lan_adj_sid(exti, false, label, SID_LABEL,
+				exti->lan_sid[1].neighbor_id);
+	}
+
+	/* Finally, add corresponding SR Link in SRDB & MPLS LFIB */
+	SET_FLAG(exti->flags, EXT_LPFLG_FIB_ENTRY_SET);
+	ospf_sr_ext_itf_add(exti);
+}
+
+/**
+ * Delete Adjacecny-SID for Extended Link LSA
+ *
+ * @param exti	Extended Link information
+ */
+static void ospf_ext_link_delete_adj_sid(struct ext_itf *exti)
+{
+	/* Process only (LAN)Adjacency-SID Type */
+	if (exti->stype != ADJ_SID && exti->stype != LAN_ADJ_SID)
+		return;
+
+	/* Release Primary & Backup Labels from Label Manager */
+	if (exti->stype == ADJ_SID) {
+		ospf_sr_local_block_release_label(exti->adj_sid[0].value);
+		ospf_sr_local_block_release_label(exti->adj_sid[1].value);
+	} else {
+		ospf_sr_local_block_release_label(exti->lan_sid[0].value);
+		ospf_sr_local_block_release_label(exti->lan_sid[1].value);
+	}
+	/* And reset corresponding TLV */
+	unset_adjacency_sid(exti);
+
+	/* Finally, remove corresponding SR Link in SRDB & MPLS LFIB */
+	UNSET_FLAG(exti->flags, EXT_LPFLG_FIB_ENTRY_SET);
+	ospf_sr_ext_itf_delete(exti);
+}
+
+/**
+ * Update Extended Link LSA once Segment Routing Label Block has been changed.
+ */
+void ospf_ext_link_srlb_update(void)
+{
+	struct listnode *node;
+	struct ext_itf *exti;
+
+
+	osr_debug("EXT (%s): Update Extended Links with new SRLB", __func__);
+
+	/* Update all Extended Link Adjaceny-SID  */
+	for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti)) {
+		/* Skip Extended Prefix */
+		if (exti->stype == PREF_SID || exti->stype == LOCAL_SID)
+			continue;
+
+		/* Skip inactive Extended Link */
+		if (!CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE))
+			continue;
+
+		ospf_ext_link_update_adj_sid(exti);
+	}
+}
+
+/*
+ * Used by Segment Routing to activate/deactivate Extended Link/Prefix flooding
+ *
+ * @param enable To activate or not Segment Routing Extended LSA flooding
+ *
+ * @return none
+ */
+void ospf_ext_update_sr(bool enable)
+{
+	struct listnode *node;
+	struct ext_itf *exti;
+
+	osr_debug("EXT (%s): %s Extended LSAs for Segment Routing ", __func__,
+		  enable ? "Enable" : "Disable");
+
+	if (enable) {
+		OspfEXT.enabled = true;
+
+		/* Refresh LSAs if already engaged or originate */
+		for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti)) {
+			/* Skip Inactive Extended Link */
+			if (!CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE))
+				continue;
+
+			/* Update Extended Link (LAN)Adj-SID if not set  */
+			if (!CHECK_FLAG(exti->flags, EXT_LPFLG_FIB_ENTRY_SET))
+				ospf_ext_link_update_adj_sid(exti);
+
+			/* Finally, flood the extended Link */
+			if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+				ospf_ext_lsa_schedule(exti, REFRESH_THIS_LSA);
+			else
+				ospf_ext_lsa_schedule(exti,
+						      REORIGINATE_THIS_LSA);
+		}
+	} else {
+		/* Start by Removing Extended LSA */
+		for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti))
+			ospf_extended_lsa_delete(exti);
+
+		/* And then disable Extended Link/Prefix */
+		OspfEXT.enabled = false;
+	}
+}
+
+/*
+ * -----------------------------------------------------------------------
+ * Following are callback functions against generic Opaque-LSAs handling
+ * -----------------------------------------------------------------------
+ */
+
+/* Add new Interface in Extended Interface List */
+static int ospf_ext_link_new_if(struct interface *ifp)
+{
+	struct ext_itf *new;
+	int rc = -1;
+
+	if (lookup_ext_by_ifp(ifp) != NULL) {
+		rc = 0; /* Do nothing here. */
+		return rc;
+	}
+
+	new = XCALLOC(MTYPE_OSPF_EXT_PARAMS, sizeof(struct ext_itf));
+
+	/* initialize new information and link back the interface */
+	new->ifp = ifp;
+	new->flags = EXT_LPFLG_LSA_INACTIVE;
+
+	listnode_add(OspfEXT.iflist, new);
+
+	rc = 0;
+	return rc;
+}
+
+/* Remove existing Interface from Extended Interface List */
+static int ospf_ext_link_del_if(struct interface *ifp)
+{
+	struct ext_itf *exti;
+	int rc = -1;
+
+	exti = lookup_ext_by_ifp(ifp);
+	if (exti != NULL) {
+		/* Flush LSA and remove Adjacency SID */
+		ospf_extended_lsa_delete(exti);
+
+		/* Dequeue listnode entry from the list. */
+		listnode_delete(OspfEXT.iflist, exti);
+
+		XFREE(MTYPE_OSPF_EXT_PARAMS, exti);
+
+		rc = 0;
+	} else {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): interface %s is not found", __func__,
+			  ifp ? ifp->name : "-");
+	}
+
+	return rc;
+}
+
+/*
+ * Determine if an Interface belongs to an Extended Link Adjacency or
+ * Extended Prefix SID type and allocate new instance value accordingly
+ */
+static void ospf_ext_ism_change(struct ospf_interface *oi, int old_status)
+{
+	struct ext_itf *exti;
+
+	/* Get interface information for Segment Routing */
+	exti = lookup_ext_by_ifp(oi->ifp);
+	if (exti == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Cannot get Extended info. from OI(%s)",
+			  __func__, IF_NAME(oi));
+		return;
+	}
+
+	/* Reset Extended information if ospf interface goes Down */
+	if (oi->state == ISM_Down) {
+		ospf_extended_lsa_delete(exti);
+		exti->area = NULL;
+		exti->flags = EXT_LPFLG_LSA_INACTIVE;
+		return;
+	}
+
+	/* Determine if interface is related to a Prefix or an Adjacency SID */
+	if (oi->type == OSPF_IFTYPE_LOOPBACK) {
+		exti->stype = PREF_SID;
+		exti->type = OPAQUE_TYPE_EXTENDED_PREFIX_LSA;
+		exti->instance = get_ext_pref_instance_value();
+		exti->area = oi->area;
+
+		/* Complete SRDB if the interface belongs to a Prefix */
+		if (OspfEXT.enabled) {
+			osr_debug("EXT (%s): Set Prefix SID to interface %s ",
+				  __func__, oi->ifp->name);
+			ospf_sr_update_local_prefix(oi->ifp, oi->address);
+		}
+	} else {
+		/* Determine if interface is related to Adj. or LAN Adj. SID */
+		if (oi->state == ISM_DR)
+			exti->stype = LAN_ADJ_SID;
+		else
+			exti->stype = ADJ_SID;
+
+		exti->type = OPAQUE_TYPE_EXTENDED_LINK_LSA;
+		exti->instance = get_ext_link_instance_value();
+		exti->area = oi->area;
+
+		/*
+		 * Note: Adjacency SID information are completed when ospf
+		 * adjacency become up see ospf_ext_link_nsm_change()
+		 */
+		if (OspfEXT.enabled)
+			osr_debug(
+				"EXT (%s): Set %sAdjacency SID for interface %s ",
+				__func__, exti->stype == ADJ_SID ? "" : "LAN-",
+				oi->ifp->name);
+	}
+}
+
+/*
+ * Finish Extended Link configuration and flood corresponding LSA
+ * when OSPF adjacency on this link fire up
+ */
+static void ospf_ext_link_nsm_change(struct ospf_neighbor *nbr, int old_status)
+{
+	struct ospf_interface *oi = nbr->oi;
+	struct ext_itf *exti;
+
+	/* Process Link only when neighbor old or new state is NSM Full */
+	if (nbr->state != NSM_Full && old_status != NSM_Full)
+		return;
+
+	/* Get interface information for Segment Routing */
+	exti = lookup_ext_by_ifp(oi->ifp);
+	if (exti == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Cannot get Extended info. from OI(%s)",
+			  __func__, IF_NAME(oi));
+		return;
+	}
+
+	/* Check that we have a valid area and ospf context */
+	if (oi->area == NULL || oi->area->ospf == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Cannot refer to OSPF from OI(%s)",
+			  __func__, IF_NAME(oi));
+		return;
+	}
+
+	/* Remove Extended Link if Neighbor State goes Down or Deleted */
+	if (OspfEXT.enabled
+	    && (nbr->state == NSM_Down || nbr->state == NSM_Deleted)) {
+		ospf_ext_link_delete_adj_sid(exti);
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+			ospf_ext_link_lsa_schedule(exti, FLUSH_THIS_LSA);
+		exti->flags = EXT_LPFLG_LSA_INACTIVE;
+		return;
+	}
+
+	/* Keep Area information in combination with SR info. */
+	exti->area = oi->area;
+
+	/* Process only Adjacency/LAN SID */
+	if (exti->stype == PREF_SID)
+		return;
+
+	switch (oi->state) {
+	case ISM_PointToPoint:
+		/* Segment ID is an Adjacency one */
+		exti->stype = ADJ_SID;
+
+		/* Set Extended Link TLV with link_id == Nbr Router ID */
+		set_ext_link(exti, OSPF_IFTYPE_POINTOPOINT, nbr->router_id,
+			     oi->address->u.prefix4);
+
+		/* And Remote Interface address */
+		set_rmt_itf_addr(exti, nbr->address.u.prefix4);
+
+		break;
+
+	case ISM_DR:
+		/* Segment ID is a LAN Adjacency for the DR only */
+		exti->stype = LAN_ADJ_SID;
+
+		/* Set Extended Link TLV with link_id == DR */
+		set_ext_link(exti, OSPF_IFTYPE_BROADCAST, DR(oi),
+			     oi->address->u.prefix4);
+
+		/* Set Neighbor ID */
+		exti->lan_sid[0].neighbor_id = nbr->router_id;
+		exti->lan_sid[1].neighbor_id = nbr->router_id;
+
+		break;
+
+	case ISM_DROther:
+	case ISM_Backup:
+		/* Segment ID is an Adjacency if not the DR */
+		exti->stype = ADJ_SID;
+
+		/* Set Extended Link TLV with link_id == DR */
+		set_ext_link(exti, OSPF_IFTYPE_BROADCAST, DR(oi),
+			     oi->address->u.prefix4);
+
+		break;
+
+	default:
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_FIB_ENTRY_SET))
+			ospf_ext_link_delete_adj_sid(exti);
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+			ospf_ext_link_lsa_schedule(exti, FLUSH_THIS_LSA);
+		exti->flags = EXT_LPFLG_LSA_INACTIVE;
+		return;
+	}
+
+	SET_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE);
+
+	if (OspfEXT.enabled) {
+		osr_debug("EXT (%s): Set %sAdjacency SID for interface %s ",
+			  __func__, exti->stype == ADJ_SID ? "" : "LAN-",
+			  oi->ifp->name);
+
+		/* Update (LAN)Adjacency SID */
+		ospf_ext_link_update_adj_sid(exti);
+
+		/* flood this links params if everything is ok */
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED))
+			ospf_ext_link_lsa_schedule(exti, REFRESH_THIS_LSA);
+		else
+			ospf_ext_link_lsa_schedule(exti, REORIGINATE_THIS_LSA);
+	}
+}
+
+/* Callbacks to handle Extended Link Segment Routing LSA information */
+static int ospf_ext_link_lsa_update(struct ospf_lsa *lsa)
+{
+	/* Sanity Check */
+	if (lsa == NULL) {
+		flog_warn(EC_OSPF_LSA_NULL, "EXT (%s): Abort! LSA is NULL",
+			  __func__);
+		return -1;
+	}
+
+	/* Process only Opaque LSA */
+	if ((lsa->data->type != OSPF_OPAQUE_AREA_LSA)
+	    && (lsa->data->type != OSPF_OPAQUE_AS_LSA))
+		return 0;
+
+	/* Process only Extended Link LSA */
+	if (GET_OPAQUE_TYPE(ntohl(lsa->data->id.s_addr))
+	    != OPAQUE_TYPE_EXTENDED_LINK_LSA)
+		return 0;
+
+	/* Check if it is not my LSA */
+	if (IS_LSA_SELF(lsa))
+		return 0;
+
+	/* Check if Extended is enable */
+	if (!OspfEXT.enabled)
+		return 0;
+
+	/* Call Segment Routing LSA update or deletion */
+	if (!IS_LSA_MAXAGE(lsa))
+		ospf_sr_ext_link_lsa_update(lsa);
+	else
+		ospf_sr_ext_link_lsa_delete(lsa);
+
+	return 0;
+}
+
+/* Callbacks to handle Extended Prefix Segment Routing LSA information */
+static int ospf_ext_pref_lsa_update(struct ospf_lsa *lsa)
+{
+
+	/* Sanity Check */
+	if (lsa == NULL) {
+		flog_warn(EC_OSPF_LSA_NULL, "EXT (%s): Abort! LSA is NULL",
+			  __func__);
+		return -1;
+	}
+
+	/* Process only Opaque LSA */
+	if ((lsa->data->type != OSPF_OPAQUE_AREA_LSA)
+	    && (lsa->data->type != OSPF_OPAQUE_AS_LSA))
+		return 0;
+
+	/* Process only Extended Prefix LSA */
+	if (GET_OPAQUE_TYPE(ntohl(lsa->data->id.s_addr))
+	    != OPAQUE_TYPE_EXTENDED_PREFIX_LSA)
+		return 0;
+
+	/* Check if it is not my LSA */
+	if (IS_LSA_SELF(lsa))
+		return 0;
+
+	/* Check if Extended is enable */
+	if (!OspfEXT.enabled)
+		return 0;
+
+	/* Call Segment Routing LSA update or deletion */
+	if (!IS_LSA_MAXAGE(lsa))
+		ospf_sr_ext_prefix_lsa_update(lsa);
+	else
+		ospf_sr_ext_prefix_lsa_delete(lsa);
+
+	return 0;
+}
+
+/*
+ * -------------------------------------------------------
+ * Following are OSPF protocol processing functions for
+ * Extended Prefix/Link Opaque LSA
+ * -------------------------------------------------------
+ */
+
+static void build_tlv_header(struct stream *s, struct tlv_header *tlvh)
+{
+	stream_put(s, tlvh, sizeof(struct tlv_header));
+}
+
+static void build_tlv(struct stream *s, struct tlv_header *tlvh)
+{
+
+	if ((tlvh != NULL) && (ntohs(tlvh->type) != 0)) {
+		build_tlv_header(s, tlvh);
+		stream_put(s, TLV_DATA(tlvh), TLV_BODY_SIZE(tlvh));
+	}
+}
+
+/* Build an Extended Prefix Opaque LSA body for extended prefix TLV */
+static void ospf_ext_pref_lsa_body_set(struct stream *s, struct ext_itf *exti)
+{
+
+	/* Sanity check */
+	if ((exti == NULL) || (exti->stype != PREF_SID))
+		return;
+
+	/* Adjust Extended Prefix TLV size */
+	TLV_LEN(exti->prefix) = htons(ntohs(TLV_LEN(exti->node_sid))
+				      + EXT_TLV_PREFIX_SIZE + TLV_HDR_SIZE);
+
+	/* Build LSA body for an Extended Prefix TLV */
+	build_tlv_header(s, &exti->prefix.header);
+	stream_put(s, TLV_DATA(&exti->prefix.header), EXT_TLV_PREFIX_SIZE);
+	/* Then add Prefix SID SubTLV */
+	build_tlv(s, &exti->node_sid.header);
+}
+
+/* Build an Extended Link Opaque LSA body for extended link TLV */
+static void ospf_ext_link_lsa_body_set(struct stream *s, struct ext_itf *exti)
+{
+	size_t size;
+
+	/* Sanity check */
+	if ((exti == NULL)
+	    || ((exti->stype != ADJ_SID) && (exti->stype != LAN_ADJ_SID)))
+		return;
+
+	if (exti->stype == ADJ_SID) {
+		/* Adjust Extended Link TLV size for Adj. SID */
+		size = EXT_TLV_LINK_SIZE + 2 * EXT_SUBTLV_ADJ_SID_SIZE
+		       + 2 * TLV_HDR_SIZE;
+		if (ntohs(TLV_TYPE(exti->rmt_itf_addr)) != 0)
+			size = size + EXT_SUBTLV_RMT_ITF_ADDR_SIZE
+			       + TLV_HDR_SIZE;
+		TLV_LEN(exti->link) = htons(size);
+
+		/* Build LSA body for an Extended Link TLV with Adj. SID */
+		build_tlv_header(s, &exti->link.header);
+		stream_put(s, TLV_DATA(&exti->link.header), EXT_TLV_LINK_SIZE);
+		/* then add Adjacency SubTLVs */
+		build_tlv(s, &exti->adj_sid[1].header);
+		build_tlv(s, &exti->adj_sid[0].header);
+
+		/* Add Cisco experimental SubTLV if interface is PtoP */
+		if (ntohs(TLV_TYPE(exti->rmt_itf_addr)) != 0)
+			build_tlv(s, &exti->rmt_itf_addr.header);
+	} else {
+		/* Adjust Extended Link TLV size for LAN SID */
+		size = EXT_TLV_LINK_SIZE
+		       + 2 * (EXT_SUBTLV_LAN_ADJ_SID_SIZE + TLV_HDR_SIZE);
+		TLV_LEN(exti->link) = htons(size);
+
+		/* Build LSA body for an Extended Link TLV with LAN SID */
+		build_tlv_header(s, &exti->link.header);
+		stream_put(s, TLV_DATA(&exti->link.header), EXT_TLV_LINK_SIZE);
+		/* then add LAN-Adjacency SubTLVs */
+		build_tlv(s, &exti->lan_sid[1].header);
+		build_tlv(s, &exti->lan_sid[0].header);
+	}
+}
+
+/* Create new Extended Prefix opaque-LSA for every extended prefix */
+static struct ospf_lsa *ospf_ext_pref_lsa_new(struct ospf_area *area,
+					      struct ext_itf *exti)
+{
+	struct stream *s;
+	struct lsa_header *lsah;
+	struct ospf_lsa *new = NULL;
+	struct ospf *top;
+	uint8_t options, lsa_type;
+	struct in_addr lsa_id;
+	struct in_addr router_id;
+	uint32_t tmp;
+	uint16_t length;
+
+	/* Sanity Check */
+	if (exti == NULL)
+		return NULL;
+
+	/* Create a stream for LSA. */
+	s = stream_new(OSPF_MAX_LSA_SIZE);
+
+	/* Prepare LSA Header */
+	lsah = (struct lsa_header *)STREAM_DATA(s);
+
+	lsa_type = OspfEXT.scope;
+
+	/*
+	 * LSA ID is a variable number identifying different instances of
+	 * Extended Prefix Opaque LSA from the same router see RFC 7684
+	 */
+	tmp = SET_OPAQUE_LSID(OPAQUE_TYPE_EXTENDED_PREFIX_LSA, exti->instance);
+	lsa_id.s_addr = htonl(tmp);
+
+	options = OSPF_OPTION_O; /* Don't forget this :-) */
+
+	/* Fix Options and Router ID depending of the flooding scope */
+	if ((OspfEXT.scope == OSPF_OPAQUE_AS_LSA) || (area == NULL)) {
+		options = OSPF_OPTION_E;
+		top = ospf_lookup_by_vrf_id(VRF_DEFAULT);
+		router_id.s_addr = top ? top->router_id.s_addr : 0;
+	} else {
+		options |= LSA_OPTIONS_GET(area); /* Get area default option */
+		options |= LSA_OPTIONS_NSSA_GET(area);
+		router_id = area->ospf->router_id;
+	}
+
+	/* Set opaque-LSA header fields. */
+	lsa_header_set(s, options, lsa_type, lsa_id, router_id);
+
+	osr_debug(
+		"EXT (%s): LSA[Type%u:%pI4]: Create an Opaque-LSA Extended Prefix Opaque LSA instance",
+		__func__, lsa_type, &lsa_id);
+
+	/* Set opaque-LSA body fields. */
+	ospf_ext_pref_lsa_body_set(s, exti);
+
+	/* Set length. */
+	length = stream_get_endp(s);
+	lsah->length = htons(length);
+
+	/* Now, create an OSPF LSA instance. */
+	new = ospf_lsa_new_and_data(length);
+
+	/* Segment Routing belongs only to default VRF */
+	new->vrf_id = VRF_DEFAULT;
+	new->area = area;
+	SET_FLAG(new->flags, OSPF_LSA_SELF);
+	memcpy(new->data, lsah, length);
+	stream_free(s);
+
+	return new;
+}
+
+/* Create new Extended Link opaque-LSA for every extended link TLV */
+static struct ospf_lsa *ospf_ext_link_lsa_new(struct ospf_area *area,
+					      struct ext_itf *exti)
+{
+	struct stream *s;
+	struct lsa_header *lsah;
+	struct ospf_lsa *new = NULL;
+	uint8_t options, lsa_type;
+	struct in_addr lsa_id;
+	uint32_t tmp;
+	uint16_t length;
+
+	/* Sanity Check */
+	if (exti == NULL)
+		return NULL;
+
+	/* Create a stream for LSA. */
+	s = stream_new(OSPF_MAX_LSA_SIZE);
+	lsah = (struct lsa_header *)STREAM_DATA(s);
+
+	options = OSPF_OPTION_O;	  /* Don't forget this :-) */
+	options |= LSA_OPTIONS_GET(area); /* Get area default option */
+	options |= LSA_OPTIONS_NSSA_GET(area);
+	/* Extended Link Opaque LSA are only flooded within an area */
+	lsa_type = OSPF_OPAQUE_AREA_LSA;
+
+	/*
+	 * LSA ID is a variable number identifying different instances of
+	 * Extended Link Opaque LSA from the same router see RFC 7684
+	 */
+	tmp = SET_OPAQUE_LSID(OPAQUE_TYPE_EXTENDED_LINK_LSA, exti->instance);
+	lsa_id.s_addr = htonl(tmp);
+
+	osr_debug(
+		"EXT (%s) LSA[Type%u:%pI4]: Create an Opaque-LSA Extended Link Opaque LSA instance",
+		__func__, lsa_type, &lsa_id);
+
+	/* Set opaque-LSA header fields. */
+	lsa_header_set(s, options, lsa_type, lsa_id, area->ospf->router_id);
+
+	/* Set opaque-LSA body fields. */
+	ospf_ext_link_lsa_body_set(s, exti);
+
+	/* Set length. */
+	length = stream_get_endp(s);
+	lsah->length = htons(length);
+
+	/* Now, create an OSPF LSA instance. */
+	new = ospf_lsa_new_and_data(length);
+
+	/* Segment Routing belongs only to default VRF */
+	new->vrf_id = VRF_DEFAULT;
+	new->area = area;
+	SET_FLAG(new->flags, OSPF_LSA_SELF);
+	memcpy(new->data, lsah, length);
+	stream_free(s);
+
+	return new;
+}
+
+/*
+ * Process the origination of an Extended Prefix Opaque LSA
+ * for every extended prefix TLV
+ */
+static int ospf_ext_pref_lsa_originate1(struct ospf_area *area,
+					struct ext_itf *exti)
+{
+	struct ospf_lsa *new;
+	int rc = -1;
+
+
+	/* Create new Opaque-LSA/Extended Prefix Opaque LSA instance. */
+	new = ospf_ext_pref_lsa_new(area, exti);
+	if (new == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): ospf_ext_pref_lsa_new() error", __func__);
+		return rc;
+	}
+
+	/* Install this LSA into LSDB. */
+	if (ospf_lsa_install(area->ospf, NULL /*oi */, new) == NULL) {
+		flog_warn(EC_OSPF_LSA_INSTALL_FAILURE,
+			  "EXT (%s): ospf_lsa_install() error", __func__);
+		ospf_lsa_unlock(&new);
+		return rc;
+	}
+
+	/* Now this Extended Prefix Opaque LSA info parameter entry has
+	 * associated LSA.
+	 */
+	SET_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED);
+
+	/* Update new LSA origination count. */
+	area->ospf->lsa_originate_count++;
+
+	/* Flood new LSA through area. */
+	ospf_flood_through_area(area, NULL /*nbr */, new);
+
+	osr_debug(
+		"EXT (%s): LSA[Type%u:%pI4]: Originate Opaque-LSAExtended Prefix Opaque LSA: Area(%pI4), Link(%s)",
+		__func__, new->data->type, &new->data->id,
+		&area->area_id, exti->ifp->name);
+	if (IS_DEBUG_OSPF(lsa, LSA_GENERATE))
+		ospf_lsa_header_dump(new->data);
+
+	rc = 0;
+
+	return rc;
+}
+
+/*
+ * Process the origination of an Extended Link Opaque LSA
+ * for every extended link TLV
+ */
+static int ospf_ext_link_lsa_originate1(struct ospf_area *area,
+					struct ext_itf *exti)
+{
+	struct ospf_lsa *new;
+	int rc = -1;
+
+	/* Create new Opaque-LSA/Extended Link Opaque LSA instance. */
+	new = ospf_ext_link_lsa_new(area, exti);
+	if (new == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): ospf_ext_link_lsa_new() error", __func__);
+		return rc;
+	}
+
+	/* Install this LSA into LSDB. */
+	if (ospf_lsa_install(area->ospf, NULL /*oi */, new) == NULL) {
+		flog_warn(EC_OSPF_LSA_INSTALL_FAILURE,
+			  "EXT (%s): ospf_lsa_install() error", __func__);
+		ospf_lsa_unlock(&new);
+		return rc;
+	}
+
+	/* Now this link-parameter entry has associated LSA. */
+	SET_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED);
+
+	/* Update new LSA origination count. */
+	area->ospf->lsa_originate_count++;
+
+	/* Flood new LSA through area. */
+	ospf_flood_through_area(area, NULL /*nbr */, new);
+
+	osr_debug(
+		"EXT (%s): LSA[Type%u:%pI4]: Originate Opaque-LSA Extended Link Opaque LSA: Area(%pI4), Link(%s)",
+		__func__, new->data->type, &new->data->id,
+		&area->area_id, exti->ifp->name);
+	if (IS_DEBUG_OSPF(lsa, LSA_GENERATE))
+		ospf_lsa_header_dump(new->data);
+
+	rc = 0;
+
+	return rc;
+}
+
+/* Trigger the origination of Extended Prefix Opaque LSAs */
+static int ospf_ext_pref_lsa_originate(void *arg)
+{
+	struct ospf_area *area = (struct ospf_area *)arg;
+	struct listnode *node;
+	struct ext_itf *exti;
+	int rc = -1;
+
+	if (!OspfEXT.enabled) {
+		zlog_info(
+			"EXT (%s): Segment Routing functionality is Disabled now",
+			__func__);
+		rc = 0; /* This is not an error case. */
+		return rc;
+	}
+	osr_debug("EXT (%s): Start Originate Prefix LSA for area %pI4",
+		  __func__, &area->area_id);
+
+	/* Check if Extended Prefix Opaque LSA is already engaged */
+	for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti)) {
+
+		/* Process only Prefix SID */
+		if (exti->stype != PREF_SID)
+			continue;
+
+		/* Process only Extended Prefix with valid Area ID */
+		if ((exti->area == NULL)
+		    || (!IPV4_ADDR_SAME(&exti->area->area_id, &area->area_id)))
+			continue;
+
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED)) {
+			if (CHECK_FLAG(exti->flags,
+				       EXT_LPFLG_LSA_FORCED_REFRESH)) {
+				flog_warn(
+					EC_OSPF_EXT_LSA_UNEXPECTED,
+					"EXT (%s): Refresh instead of Originate",
+					__func__);
+				UNSET_FLAG(exti->flags,
+					   EXT_LPFLG_LSA_FORCED_REFRESH);
+				ospf_ext_pref_lsa_schedule(exti,
+							   REFRESH_THIS_LSA);
+			}
+			continue;
+		}
+
+		/* Ok, let's try to originate an LSA */
+		osr_debug(
+			"EXT (%s): Let's finally re-originate the LSA 7.0.0.%u for Itf %s", __func__, exti->instance,
+			exti->ifp ? exti->ifp->name : "");
+		ospf_ext_pref_lsa_originate1(area, exti);
+	}
+
+	rc = 0;
+	return rc;
+}
+
+/* Trigger the origination of Extended Link Opaque LSAs */
+static int ospf_ext_link_lsa_originate(void *arg)
+{
+	struct ospf_area *area = (struct ospf_area *)arg;
+	struct listnode *node;
+	struct ext_itf *exti;
+	int rc = -1;
+
+	if (!OspfEXT.enabled) {
+		zlog_info(
+			"EXT (%s): Segment Routing functionality is Disabled now",
+			__func__);
+		rc = 0; /* This is not an error case. */
+		return rc;
+	}
+
+	/* Check if Extended Prefix Opaque LSA is already engaged */
+	for (ALL_LIST_ELEMENTS_RO(OspfEXT.iflist, node, exti)) {
+		/* Process only Adjacency or LAN SID */
+		if (exti->stype == PREF_SID)
+			continue;
+
+		/* Skip Inactive Extended Link */
+		if (!CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE))
+			continue;
+
+		/* Process only Extended Link with valid Area ID */
+		if ((exti->area == NULL)
+		    || (!IPV4_ADDR_SAME(&exti->area->area_id, &area->area_id)))
+			continue;
+
+		/* Check if LSA not already engaged */
+		if (CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED)) {
+			if (CHECK_FLAG(exti->flags,
+				       EXT_LPFLG_LSA_FORCED_REFRESH)) {
+				flog_warn(
+					EC_OSPF_EXT_LSA_UNEXPECTED,
+					"EXT (%s): Refresh instead of Originate",
+					__func__);
+				UNSET_FLAG(exti->flags,
+					   EXT_LPFLG_LSA_FORCED_REFRESH);
+				ospf_ext_link_lsa_schedule(exti,
+							   REFRESH_THIS_LSA);
+			}
+			continue;
+		}
+
+		/* Ok, let's try to originate an LSA */
+		osr_debug(
+			"EXT (%s): Let's finally reoriginate the LSA 8.0.0.%u for Itf %s through the Area %pI4", __func__,
+			exti->instance,	exti->ifp ? exti->ifp->name : "-",
+			&area->area_id);
+		ospf_ext_link_lsa_originate1(area, exti);
+	}
+
+	rc = 0;
+	return rc;
+}
+
+/* Refresh an Extended Prefix Opaque LSA */
+static struct ospf_lsa *ospf_ext_pref_lsa_refresh(struct ospf_lsa *lsa)
+{
+	struct ospf_lsa *new = NULL;
+	struct ospf_area *area = lsa->area;
+	struct ospf *top;
+	struct ext_itf *exti;
+
+	if (!OspfEXT.enabled) {
+		/*
+		 * This LSA must have flushed before due to Extended Prefix
+		 * Opaque LSA status change.
+		 * It seems a slip among routers in the routing domain.
+		 */
+		zlog_info(
+			"EXT (%s): Segment Routing functionality is Disabled",
+			__func__);
+		/* Flush it anyway. */
+		lsa->data->ls_age = htons(OSPF_LSA_MAXAGE);
+	}
+
+	/* Lookup this lsa corresponding Extended parameters */
+	exti = lookup_ext_by_instance(lsa);
+	if (exti == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Invalid parameter LSA ID", __func__);
+		/* Flush it anyway. */
+		lsa->data->ls_age = htons(OSPF_LSA_MAXAGE);
+	}
+
+	/* Check if Interface was not disable in the interval */
+	if ((exti != NULL) && !CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE)) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Interface was Disabled: Flush it!",
+			  __func__);
+		/* Flush it anyway. */
+		lsa->data->ls_age = htons(OSPF_LSA_MAXAGE);
+	}
+
+	/* If the lsa's age reached to MaxAge, start flushing procedure. */
+	if (IS_LSA_MAXAGE(lsa)) {
+		if (exti)
+			UNSET_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED);
+		ospf_opaque_lsa_flush_schedule(lsa);
+		return NULL;
+	}
+
+	/* Create new Opaque-LSA/Extended Prefix Opaque LSA instance. */
+	new = ospf_ext_pref_lsa_new(area, exti);
+
+	if (new == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): ospf_ext_pref_lsa_new() error", __func__);
+		return NULL;
+	}
+	new->data->ls_seqnum = lsa_seqnum_increment(lsa);
+
+	/*
+	 * Install this LSA into LSDB
+	 * Given "lsa" will be freed in the next function
+	 * As area could be NULL i.e. when using OPAQUE_LSA_AS, we prefer to use
+	 * ospf_lookup() to get ospf instance
+	 */
+	if (area)
+		top = area->ospf;
+	else
+		top = ospf_lookup_by_vrf_id(VRF_DEFAULT);
+
+	if (ospf_lsa_install(top, NULL /*oi */, new) == NULL) {
+		flog_warn(EC_OSPF_LSA_INSTALL_FAILURE,
+			  "EXT (%s): ospf_lsa_install() error", __func__);
+		ospf_lsa_unlock(&new);
+		return NULL;
+	}
+
+	/* Flood updated LSA through the Prefix Area according to the RFC7684 */
+	ospf_flood_through_area(area, NULL /*nbr */, new);
+
+	/* Debug logging. */
+	osr_debug("EXT (%s): LSA[Type%u:%pI4] Refresh Extended Prefix LSA",
+		  __func__, new->data->type, &new->data->id);
+	if (IS_DEBUG_OSPF(lsa, LSA_GENERATE))
+		ospf_lsa_header_dump(new->data);
+
+
+	return new;
+}
+
+/* Refresh an Extended Link Opaque LSA */
+static struct ospf_lsa *ospf_ext_link_lsa_refresh(struct ospf_lsa *lsa)
+{
+	struct ext_itf *exti;
+	struct ospf_area *area = lsa->area;
+	struct ospf *top = area->ospf;
+	struct ospf_lsa *new = NULL;
+
+	if (!OspfEXT.enabled) {
+		/*
+		 * This LSA must have flushed before due to OSPF-SR status
+		 * change. It seems a slip among routers in the routing domain.
+		 */
+		zlog_info("EXT (%s): Segment Routing functionality is Disabled",
+			  __func__);
+		/* Flush it anyway. */
+		lsa->data->ls_age = htons(OSPF_LSA_MAXAGE);
+	}
+
+	/* Lookup this LSA corresponding Extended parameters */
+	exti = lookup_ext_by_instance(lsa);
+	if (exti == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Invalid parameter LSA ID", __func__);
+		/* Flush it anyway. */
+		lsa->data->ls_age = htons(OSPF_LSA_MAXAGE);
+	}
+
+	/* Check if Interface was not disable in the interval */
+	if ((exti != NULL) && !CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE)) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Interface was Disabled: Flush it!",
+			  __func__);
+		lsa->data->ls_age = htons(OSPF_LSA_MAXAGE);
+	}
+
+	/* If the lsa's age reached to MaxAge, start flushing procedure */
+	if (IS_LSA_MAXAGE(lsa)) {
+		if (exti)
+			UNSET_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED);
+		ospf_opaque_lsa_flush_schedule(lsa);
+		return NULL;
+	}
+
+	/* Create new Opaque-LSA/Extended Link instance */
+	new = ospf_ext_link_lsa_new(area, exti);
+	if (new == NULL) {
+		flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+			  "EXT (%s): Error creating new LSA", __func__);
+		return NULL;
+	}
+	new->data->ls_seqnum = lsa_seqnum_increment(lsa);
+
+	/* Install this LSA into LSDB. */
+	/* Given "lsa" will be freed in the next function */
+	if (ospf_lsa_install(top, NULL /*oi */, new) == NULL) {
+		flog_warn(EC_OSPF_LSA_INSTALL_FAILURE,
+			  "EXT (%s): Error installing new LSA", __func__);
+		ospf_lsa_unlock(&new);
+		return NULL;
+	}
+
+	/* Flood updated LSA through the link Area according to the RFC7684 */
+	ospf_flood_through_area(area, NULL /*nbr */, new);
+
+	/* Debug logging. */
+	osr_debug("EXT (%s): LSA[Type%u:%pI4]: Refresh Extended Link LSA",
+		  __func__, new->data->type, &new->data->id);
+	if (IS_DEBUG_OSPF(lsa, LSA_GENERATE))
+		ospf_lsa_header_dump(new->data);
+
+	return new;
+}
+
+/* Schedule Extended Prefix Opaque LSA origination/refreshment/flushing */
+static void ospf_ext_pref_lsa_schedule(struct ext_itf *exti,
+				       enum lsa_opcode opcode)
+{
+	struct ospf_lsa lsa;
+	struct lsa_header lsah;
+	struct ospf *top;
+	uint32_t tmp;
+
+	memset(&lsa, 0, sizeof(lsa));
+	memset(&lsah, 0, sizeof(lsah));
+
+	/* Sanity Check */
+	if (exti == NULL)
+		return;
+
+	/* Check if the corresponding link is ready to be flooded */
+	if (!(CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE)))
+		return;
+
+	osr_debug("EXT (%s): Schedule %s%s%s LSA for interface %s", __func__,
+		  opcode == REORIGINATE_THIS_LSA ? "Re-Originate" : "",
+		  opcode == REFRESH_THIS_LSA ? "Refresh" : "",
+		  opcode == FLUSH_THIS_LSA ? "Flush" : "",
+		  exti->ifp ? exti->ifp->name : "-");
+
+	/* Verify Area */
+	if (exti->area == NULL) {
+		osr_debug(
+			"EXT (%s): Area is not yet set. Try to use Backbone Area",
+			__func__);
+
+		top = ospf_lookup_by_vrf_id(VRF_DEFAULT);
+		struct in_addr backbone = {.s_addr = INADDR_ANY};
+		exti->area = ospf_area_lookup_by_area_id(top, backbone);
+		if (exti->area == NULL) {
+			flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+				  "EXT (%s): Unable to set Area", __func__);
+			return;
+		}
+	}
+	/* Set LSA header information */
+	lsa.area = exti->area;
+	lsa.data = &lsah;
+	lsah.type = OSPF_OPAQUE_AREA_LSA;
+	tmp = SET_OPAQUE_LSID(OPAQUE_TYPE_EXTENDED_PREFIX_LSA, exti->instance);
+	lsah.id.s_addr = htonl(tmp);
+
+	switch (opcode) {
+	case REORIGINATE_THIS_LSA:
+		ospf_opaque_lsa_reoriginate_schedule(
+			(void *)exti->area, OSPF_OPAQUE_AREA_LSA,
+			OPAQUE_TYPE_EXTENDED_PREFIX_LSA);
+		break;
+	case REFRESH_THIS_LSA:
+		ospf_opaque_lsa_refresh_schedule(&lsa);
+		break;
+	case FLUSH_THIS_LSA:
+		UNSET_FLAG(exti->flags, EXT_LPFLG_LSA_ENGAGED);
+		ospf_opaque_lsa_flush_schedule(&lsa);
+		break;
+	}
+}
+
+/* Schedule Extended Link Opaque LSA origination/refreshment/flushing */
+static void ospf_ext_link_lsa_schedule(struct ext_itf *exti,
+				       enum lsa_opcode opcode)
+{
+	struct ospf_lsa lsa;
+	struct lsa_header lsah;
+	struct ospf *top;
+	uint32_t tmp;
+
+	memset(&lsa, 0, sizeof(lsa));
+	memset(&lsah, 0, sizeof(lsah));
+
+	/* Sanity Check */
+	if (exti == NULL)
+		return;
+
+	/* Check if the corresponding link is ready to be flooded */
+	if (!(CHECK_FLAG(exti->flags, EXT_LPFLG_LSA_ACTIVE)))
+		return;
+
+	osr_debug("EXT (%s): Schedule %s%s%s LSA for interface %s", __func__,
+		  opcode == REORIGINATE_THIS_LSA ? "Re-Originate" : "",
+		  opcode == REFRESH_THIS_LSA ? "Refresh" : "",
+		  opcode == FLUSH_THIS_LSA ? "Flush" : "",
+		  exti->ifp ? exti->ifp->name : "-");
+
+	/* Verify Area */
+	if (exti->area == NULL) {
+		osr_debug(
+			"EXT (%s): Area is not yet set. Try to use Backbone Area",
+			__func__);
+
+		top = ospf_lookup_by_vrf_id(VRF_DEFAULT);
+		struct in_addr backbone = {.s_addr = INADDR_ANY};
+		exti->area = ospf_area_lookup_by_area_id(top, backbone);
+		if (exti->area == NULL) {
+			flog_warn(EC_OSPF_EXT_LSA_UNEXPECTED,
+				  "EXT (%s): Unable to set Area", __func__);
+			return;
+		}
+	}
+	/* Set LSA header information */
+	lsa.area = exti->area;
+	lsa.data = &lsah;
+	lsah.type = OSPF_OPAQUE_AREA_LSA;
+	tmp = SET_OPAQUE_LSID(OPAQUE_TYPE_EXTENDED_LINK_LSA, exti->instance);
+	lsah.id.s_addr = htonl(tmp);
+
+	switch (opcode) {
+	case REORIGINATE_THIS_LSA:
+		ospf_opaque_lsa_reoriginate_schedule(
+			(void *)exti->area, OSPF_OPAQUE_AREA_LSA,
+			OPAQUE_TYPE_EXTENDED_LINK_LSA);
+		break;
+	case REFRESH_THIS_LSA:
+		ospf_opaque_lsa_refresh_schedule(&lsa);
+		break;
+	case FLUSH_THIS_LSA:
+		ospf_opaque_lsa_flush_schedule(&lsa);
+		break;
+	}
+}
+
+/* Schedule Extended Link or Prefix depending of the Type of LSA */
+static void ospf_ext_lsa_schedule(struct ext_itf *exti, enum lsa_opcode op)
+{
+
+	if (exti->stype == PREF_SID)
+		ospf_ext_pref_lsa_schedule(exti, op);
+	else
+		ospf_ext_link_lsa_schedule(exti, op);
+}
+
+/*
+ * ------------------------------------
+ * Following are vty show functions.
+ * ------------------------------------
+ */
+
+#define check_tlv_size(size, msg)                                              \
+	do {                                                                   \
+		if (ntohs(tlvh->length) != size) {                             \
+			vty_out(vty, "  Wrong %s TLV size: %d(%d). Abort!\n",  \
+				msg, ntohs(tlvh->length), size);               \
+			return size + TLV_HDR_SIZE;                            \
+		}                                                              \
+	} while (0)
+
+/* Cisco experimental SubTLV */
+static uint16_t show_vty_ext_link_rmt_itf_addr(struct vty *vty,
+					       struct tlv_header *tlvh)
+{
+	struct ext_subtlv_rmt_itf_addr *top =
+		(struct ext_subtlv_rmt_itf_addr *)tlvh;
+
+	check_tlv_size(EXT_SUBTLV_RMT_ITF_ADDR_SIZE, "Remote Itf. Address");
+
+	vty_out(vty,
+		"  Remote Interface Address Sub-TLV: Length %u\n	Address: %pI4\n",
+		ntohs(top->header.length), &top->value);
+
+	return TLV_SIZE(tlvh);
+}
+
+/* Adjacency SID SubTLV */
+static uint16_t show_vty_ext_link_adj_sid(struct vty *vty,
+					  struct tlv_header *tlvh)
+{
+	struct ext_subtlv_adj_sid *top = (struct ext_subtlv_adj_sid *)tlvh;
+
+	check_tlv_size(EXT_SUBTLV_ADJ_SID_SIZE, "Adjacency SID");
+
+	vty_out(vty,
+		"  Adj-SID Sub-TLV: Length %u\n\tFlags: 0x%x\n\tMT-ID:0x%x\n\tWeight: 0x%x\n\t%s: %u\n",
+		ntohs(top->header.length), top->flags, top->mtid, top->weight,
+		CHECK_FLAG(top->flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG) ? "Label"
+								     : "Index",
+		CHECK_FLAG(top->flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG)
+			? GET_LABEL(ntohl(top->value))
+			: ntohl(top->value));
+
+	return TLV_SIZE(tlvh);
+}
+
+/* LAN Adjacency SubTLV */
+static uint16_t show_vty_ext_link_lan_adj_sid(struct vty *vty,
+					      struct tlv_header *tlvh)
+{
+	struct ext_subtlv_lan_adj_sid *top =
+		(struct ext_subtlv_lan_adj_sid *)tlvh;
+
+	check_tlv_size(EXT_SUBTLV_LAN_ADJ_SID_SIZE, "Lan-Adjacency SID");
+
+	vty_out(vty,
+		"  LAN-Adj-SID Sub-TLV: Length %u\n\tFlags: 0x%x\n\tMT-ID:0x%x\n\tWeight: 0x%x\n\tNeighbor ID: %pI4\n\t%s: %u\n",
+		ntohs(top->header.length), top->flags, top->mtid, top->weight,
+		&top->neighbor_id,
+		CHECK_FLAG(top->flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG) ? "Label"
+								     : "Index",
+		CHECK_FLAG(top->flags, EXT_SUBTLV_LINK_ADJ_SID_VFLG)
+			? GET_LABEL(ntohl(top->value))
+			: ntohl(top->value));
+
+	return TLV_SIZE(tlvh);
+}
+
+static uint16_t show_vty_unknown_tlv(struct vty *vty, struct tlv_header *tlvh,
+				     size_t buf_size)
+{
+	if (TLV_SIZE(tlvh) > buf_size) {
+		vty_out(vty, "    TLV size %d exceeds buffer size. Abort!",
+			TLV_SIZE(tlvh));
+		return buf_size;
+	}
+
+	vty_out(vty, "    Unknown TLV: [type(0x%x), length(0x%x)]\n",
+		ntohs(tlvh->type), ntohs(tlvh->length));
+
+	return TLV_SIZE(tlvh);
+}
+
+/* Extended Link Sub TLVs */
+static uint16_t show_vty_link_info(struct vty *vty, struct tlv_header *ext,
+				   size_t buf_size)
+{
+	struct ext_tlv_link *top = (struct ext_tlv_link *)ext;
+	struct tlv_header *tlvh;
+	uint16_t length = ntohs(top->header.length);
+	uint16_t sum = 0;
+
+	/* Verify that TLV length is valid against remaining buffer size */
+	if (length > buf_size) {
+		vty_out(vty,
+			"  Extended Link TLV size %d exceeds buffer size. Abort!\n",
+			length);
+		return buf_size;
+	}
+
+	vty_out(vty,
+		"  Extended Link TLV: Length %u\n	Link Type: 0x%x\n"
+		"	Link ID: %pI4\n",
+		ntohs(top->header.length), top->link_type,
+		&top->link_id);
+	vty_out(vty, "	Link data: %pI4\n", &top->link_data);
+
+	/* Skip Extended TLV and parse sub-TLVs */
+	length -= EXT_TLV_LINK_SIZE;
+	tlvh = (struct tlv_header *)((char *)(ext) + TLV_HDR_SIZE
+				     + EXT_TLV_LINK_SIZE);
+	for (; sum < length && tlvh; tlvh = TLV_HDR_NEXT(tlvh)) {
+		switch (ntohs(tlvh->type)) {
+		case EXT_SUBTLV_ADJ_SID:
+			sum += show_vty_ext_link_adj_sid(vty, tlvh);
+			break;
+		case EXT_SUBTLV_LAN_ADJ_SID:
+			sum += show_vty_ext_link_lan_adj_sid(vty, tlvh);
+			break;
+		case EXT_SUBTLV_RMT_ITF_ADDR:
+			sum += show_vty_ext_link_rmt_itf_addr(vty, tlvh);
+			break;
+		default:
+			sum += show_vty_unknown_tlv(vty, tlvh, length - sum);
+			break;
+		}
+	}
+
+	return sum + sizeof(struct ext_tlv_link);
+}
+
+/* Extended Link TLVs */
+static void ospf_ext_link_show_info(struct vty *vty, struct json_object *json,
+				    struct ospf_lsa *lsa)
+{
+	struct lsa_header *lsah = lsa->data;
+	struct tlv_header *tlvh;
+	uint16_t length = 0, sum = 0;
+
+	if (json)
+		return;
+
+	/* Initialize TLV browsing */
+	length = lsa->size - OSPF_LSA_HEADER_SIZE;
+
+	for (tlvh = TLV_HDR_TOP(lsah); sum < length && tlvh;
+	     tlvh = TLV_HDR_NEXT(tlvh)) {
+		switch (ntohs(tlvh->type)) {
+		case EXT_TLV_LINK:
+			sum += show_vty_link_info(vty, tlvh, length - sum);
+			break;
+		default:
+			sum += show_vty_unknown_tlv(vty, tlvh, length - sum);
+			break;
+		}
+	}
+}
+
+/* Prefix SID SubTLV */
+static uint16_t show_vty_ext_pref_pref_sid(struct vty *vty,
+					   struct tlv_header *tlvh)
+{
+	struct ext_subtlv_prefix_sid *top =
+		(struct ext_subtlv_prefix_sid *)tlvh;
+
+	check_tlv_size(EXT_SUBTLV_PREFIX_SID_SIZE, "Prefix SID");
+
+	vty_out(vty,
+		"  Prefix SID Sub-TLV: Length %u\n\tAlgorithm: %u\n\tFlags: 0x%x\n\tMT-ID:0x%x\n\t%s: %u\n",
+		ntohs(top->header.length), top->algorithm, top->flags,
+		top->mtid,
+		CHECK_FLAG(top->flags, EXT_SUBTLV_PREFIX_SID_VFLG) ? "Label"
+								   : "Index",
+		CHECK_FLAG(top->flags, EXT_SUBTLV_PREFIX_SID_VFLG)
+			? GET_LABEL(ntohl(top->value))
+			: ntohl(top->value));
+
+	return TLV_SIZE(tlvh);
+}
+
+/* Extended Prefix SubTLVs */
+static uint16_t show_vty_pref_info(struct vty *vty, struct tlv_header *ext,
+				   size_t buf_size)
+{
+	struct ext_tlv_prefix *top = (struct ext_tlv_prefix *)ext;
+	struct tlv_header *tlvh;
+	uint16_t length = ntohs(top->header.length);
+	uint16_t sum = 0;
+
+	/* Verify that TLV length is valid against remaining buffer size */
+	if (length > buf_size) {
+		vty_out(vty,
+			"  Extended Link TLV size %d exceeds buffer size. Abort!\n",
+			length);
+		return buf_size;
+	}
+
+	vty_out(vty,
+		"  Extended Prefix TLV: Length %u\n\tRoute Type: %u\n"
+		"\tAddress Family: 0x%x\n\tFlags: 0x%x\n\tAddress: %pI4/%u\n",
+		ntohs(top->header.length), top->route_type, top->af, top->flags,
+		&top->address, top->pref_length);
+
+	/* Skip Extended Prefix TLV and parse sub-TLVs */
+	length -= EXT_TLV_PREFIX_SIZE;
+	tlvh = (struct tlv_header *)((char *)(ext) + TLV_HDR_SIZE
+				     + EXT_TLV_PREFIX_SIZE);
+	for (; sum < length && tlvh; tlvh = TLV_HDR_NEXT(tlvh)) {
+		switch (ntohs(tlvh->type)) {
+		case EXT_SUBTLV_PREFIX_SID:
+			sum += show_vty_ext_pref_pref_sid(vty, tlvh);
+			break;
+		default:
+			sum += show_vty_unknown_tlv(vty, tlvh, length - sum);
+			break;
+		}
+	}
+
+	return sum + sizeof(struct ext_tlv_prefix);
+}
+
+/* Extended Prefix TLVs */
+static void ospf_ext_pref_show_info(struct vty *vty, struct json_object *json,
+				    struct ospf_lsa *lsa)
+{
+	struct lsa_header *lsah = lsa->data;
+	struct tlv_header *tlvh;
+	uint16_t length = 0, sum = 0;
+
+	if (json)
+		return;
+
+	/* Initialize TLV browsing */
+	length = lsa->size - OSPF_LSA_HEADER_SIZE;
+
+	for (tlvh = TLV_HDR_TOP(lsah); sum < length && tlvh;
+	     tlvh = TLV_HDR_NEXT(tlvh)) {
+		switch (ntohs(tlvh->type)) {
+		case EXT_TLV_PREFIX:
+			sum += show_vty_pref_info(vty, tlvh, length - sum);
+			break;
+		default:
+			sum += show_vty_unknown_tlv(vty, tlvh, length - sum);
+			break;
+		}
+	}
+}