Cannot ping to link-local ipv6 interface address of the switch.

neighsyncd/neighsync.cpp

@@ -60,9 +60,7 @@ void NeighSync::onMsg(int nlmsg_type, struct nl_object *obj)
     key+= ":";
 
     nl_addr2str(rtnl_neigh_get_dst(neigh), ipStr, MAX_ADDR_SIZE);
-    /* Ignore IPv6 link-local addresses as neighbors */
-    if (family == IPV6_NAME && IN6_IS_ADDR_LINKLOCAL(nl_addr_get_binary_addr(rtnl_neigh_get_dst(neigh))))
-        return;
+
     /* Ignore IPv6 multicast link-local addresses as neighbors */
     if (family == IPV6_NAME && IN6_IS_ADDR_MC_LINKLOCAL(nl_addr_get_binary_addr(rtnl_neigh_get_dst(neigh))))
         return;

orchagent/routeorch.cpp

@@ -103,6 +103,83 @@ RouteOrch::RouteOrch(DBConnector *db, string tableName, NeighOrch *neighOrch) :
     m_syncdRoutes[v6_default_ip_prefix] = IpAddresses();
 
     SWSS_LOG_NOTICE("Create IPv6 default route with packet action drop");
+
+    /* All the interfaces have the same MAC address and hence the same
+     * auto-generated link-local ipv6 address with eui64 interface-id.
+     * Hence add a single /128 route entry for the link-local interface
+     * address pointing to the CPU port.
+     */
+    addLinkLocalRouteToMe(gVirtualRouterId);
+
+    /* TODO: Add the link-local /128 route to cpu in every VRF created from
+     * vrforch::addOperation. */
+}
+
+std::string RouteOrch::getLinkLocalEui64Addr(void)
+{
+    SWSS_LOG_ENTER();
+
+    string        ipPrefix;
+    const uint8_t *gmac = gMacAddress.getMac();
+
+    uint8_t        eui64_interface_id[EUI64_INTF_ID_LEN];
+    char           ipv6_ll_addr[IP6_ADDR_STR_LEN] = {0};
+
+    eui64_interface_id[0] = gmac[0] ^ 0x02;
+    eui64_interface_id[1] = gmac[1];
+    eui64_interface_id[2] = gmac[2];
+    eui64_interface_id[3] = 0xff;
+    eui64_interface_id[4] = 0xfe;
+    eui64_interface_id[5] = gmac[3];
+    eui64_interface_id[6] = gmac[4];
+    eui64_interface_id[7] = gmac[5];
+
+    snprintf(ipv6_ll_addr, IP6_ADDR_STR_LEN, "fe80::%02x%02x:%02x%02x:%02x%02x:%02x%02x",
+             eui64_interface_id[0], eui64_interface_id[1], eui64_interface_id[2],
+             eui64_interface_id[3], eui64_interface_id[4], eui64_interface_id[5],
+             eui64_interface_id[6], eui64_interface_id[7]);
+
+    ipPrefix = string(ipv6_ll_addr);
+
+    return ipPrefix;
+}
+
+void RouteOrch::addLinkLocalRouteToMe(sai_object_id_t vrf_id)
+{
+    /* Link-local IPv6 address autogenerated by kernel with eui64 interface-id
+     * derived from the MAC address of the host interface.
+     */
+    IpPrefix linklocal_prefix = getLinkLocalEui64Addr();
+
+    sai_route_entry_t unicast_route_entry;
+    unicast_route_entry.switch_id = gSwitchId;
+    unicast_route_entry.vr_id = vrf_id;
+    copy(unicast_route_entry.destination, linklocal_prefix.getIp());
+
+    sai_attribute_t attr;
+    vector<sai_attribute_t> attrs;
+
+    attr.id = SAI_ROUTE_ENTRY_ATTR_PACKET_ACTION;
+    attr.value.s32 = SAI_PACKET_ACTION_FORWARD;
+    attrs.push_back(attr);
+
+    Port cpu_port;
+    gPortsOrch->getCpuPort(cpu_port);
+
+    attr.id = SAI_ROUTE_ENTRY_ATTR_NEXT_HOP_ID;
+    attr.value.oid = cpu_port.m_port_id;
+    attrs.push_back(attr);
+
+    sai_status_t status = sai_route_api->create_route_entry(&unicast_route_entry, (uint32_t)attrs.size(), attrs.data());
+    if (status != SAI_STATUS_SUCCESS)
+    {
+        SWSS_LOG_ERROR("Failed to create link local ipv6 host route %s to cpu, rv:%d",
+                       linklocal_prefix.getIp().to_string().c_str(), status);
+    }
+
+    gCrmOrch->incCrmResUsedCounter(CrmResourceType::CRM_IPV6_ROUTE);
+
+    SWSS_LOG_NOTICE("Created link local ipv6 host route  %s to cpu", linklocal_prefix.to_string().c_str());
 }
 
 bool RouteOrch::hasNextHopGroup(const IpAddresses& ipAddresses) const

orchagent/routeorch.h

@@ -15,6 +15,11 @@
 /* Maximum next hop group number */
 #define NHGRP_MAX_SIZE 128
 
+/* Length of the Interface Id value in EUI64 format */
+#define EUI64_INTF_ID_LEN 8
+
+#define IP6_ADDR_STR_LEN  40
+
 typedef std::map<IpAddress, sai_object_id_t> NextHopGroupMembers;
 
 struct NextHopGroupEntry
@@ -84,6 +89,9 @@ class RouteOrch : public Orch, public Subject
     bool addRoute(IpPrefix, IpAddresses);
     bool removeRoute(IpPrefix);
 
+    std::string getLinkLocalEui64Addr(void);
+    void        addLinkLocalRouteToMe(sai_object_id_t vrf_id);
+
     void doTask(Consumer& consumer);
 };