Author: Akhilesh Samineni <47657796+AkhileshSamineni@users.noreply.gi…

…thub.com>

Date:   Thu Aug 5 23:49:44 2021 +0530
    Code changes to support IPv6 Link local enhancements (sonic-net#1463)

cfgmgr/intfmgr.cpp

@@ -446,6 +446,7 @@ bool IntfMgr::doIntfGeneralTask(const vector<string>& keys,
     string nat_zone = "";
     string proxy_arp = "";
     string grat_arp = "";
+    string ipv6_link_local_mode = "";
 
     for (auto idx : data)
     {
@@ -477,6 +478,10 @@ bool IntfMgr::doIntfGeneralTask(const vector<string>& keys,
         {
             nat_zone = value;
         }
+        else if (field == "ipv6_use_link_local_only")
+        {
+            ipv6_link_local_mode = value;
+        }
     }
 
     if (op == SET_COMMAND)
@@ -516,6 +521,13 @@ bool IntfMgr::doIntfGeneralTask(const vector<string>& keys,
             {
                 FieldValueTuple fvTuple("nat_zone", nat_zone);
                 data.push_back(fvTuple);
+            }
+
+			/* Set ipv6 mode */
+            if (!ipv6_link_local_mode.empty())
+            {
+                FieldValueTuple fvTuple("ipv6_use_link_local_only", ipv6_link_local_mode);
+                data.push_back(fvTuple);
             }
         }
 
@@ -686,8 +698,8 @@ bool IntfMgr::doIntfAddrTask(const vector<string>& keys,
         std::vector<FieldValueTuple> fvVector;
         FieldValueTuple f("family", ip_prefix.isV4() ? IPV4_NAME : IPV6_NAME);
 
-        // Don't send link local config to AppDB and Orchagent
-        if (ip_prefix.getIp().getAddrScope() != IpAddress::AddrScope::LINK_SCOPE)
+        // Don't send ipv4 link local config to AppDB and Orchagent
+        if ((ip_prefix.isV4() == false) || (ip_prefix.getIp().getAddrScope() != IpAddress::AddrScope::LINK_SCOPE))
         {
             FieldValueTuple s("scope", "global");
             fvVector.push_back(s);
@@ -700,8 +712,8 @@ bool IntfMgr::doIntfAddrTask(const vector<string>& keys,
     {
         setIntfIp(alias, "del", ip_prefix);
 
-        // Don't send link local config to AppDB and Orchagent
-        if (ip_prefix.getIp().getAddrScope() != IpAddress::AddrScope::LINK_SCOPE)
+        // Don't send ipv4 link local config to AppDB and Orchagent
+        if ((ip_prefix.isV4() == false) || (ip_prefix.getIp().getAddrScope() != IpAddress::AddrScope::LINK_SCOPE))
         {
             m_appIntfTableProducer.del(appKey);
             m_stateIntfTable.del(keys[0] + state_db_key_delimiter + keys[1]);

neighsyncd/neighsync.cpp

@@ -13,13 +13,17 @@
 
 #include "neighsync.h"
 #include "warm_restart.h"
+#include <algorithm>
 
 using namespace std;
 using namespace swss;
 
-NeighSync::NeighSync(RedisPipeline *pipelineAppDB, DBConnector *stateDb) :
+NeighSync::NeighSync(RedisPipeline *pipelineAppDB, DBConnector *stateDb, DBConnector *cfgDb) :
     m_neighTable(pipelineAppDB, APP_NEIGH_TABLE_NAME),
-    m_stateNeighRestoreTable(stateDb, STATE_NEIGH_RESTORE_TABLE_NAME)
+    m_stateNeighRestoreTable(stateDb, STATE_NEIGH_RESTORE_TABLE_NAME),
+    m_cfgInterfaceTable(cfgDb, CFG_INTF_TABLE_NAME),
+    m_cfgLagInterfaceTable(cfgDb, CFG_LAG_INTF_TABLE_NAME),
+    m_cfgVlanInterfaceTable(cfgDb, CFG_VLAN_INTF_TABLE_NAME)
 {
     m_AppRestartAssist = new AppRestartAssist(pipelineAppDB, "neighsyncd", "swss", DEFAULT_NEIGHSYNC_WARMSTART_TIMER);
     if (m_AppRestartAssist)
@@ -57,6 +61,7 @@ void NeighSync::onMsg(int nlmsg_type, struct nl_object *obj)
     struct rtnl_neigh *neigh = (struct rtnl_neigh *)obj;
     string key;
     string family;
+    string intfName;
 
     if ((nlmsg_type != RTM_NEWNEIGH) && (nlmsg_type != RTM_GETNEIGH) &&
         (nlmsg_type != RTM_DELNEIGH))
@@ -70,12 +75,18 @@ void NeighSync::onMsg(int nlmsg_type, struct nl_object *obj)
         return;
 
     key+= LinkCache::getInstance().ifindexToName(rtnl_neigh_get_ifindex(neigh));
+    intfName = key;
     key+= ":";
 
     nl_addr2str(rtnl_neigh_get_dst(neigh), ipStr, MAX_ADDR_SIZE);
-    /* Ignore IPv6 link-local addresses as neighbors */
+    /* Ignore IPv6 link-local addresses as neighbors, if ipv6 link local mode is disabled */
     if (family == IPV6_NAME && IN6_IS_ADDR_LINKLOCAL(nl_addr_get_binary_addr(rtnl_neigh_get_dst(neigh))))
-        return;
+    {
+        if (isLinkLocalEnabled(intfName) == false)
+        {
+            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;
@@ -124,3 +135,10 @@ void NeighSync::onMsg(int nlmsg_type, struct nl_object *obj)
         m_neighTable.set(key, fvVector);
     }
 }
+
+/* To check the ipv6 link local is enabled on a given port */
+bool NeighSync::isLinkLocalEnabled(const string &port)
+{
+    SWSS_LOG_INFO("IPv6 Link local is enabled on %s", port.c_str());
+    return true;
+}

neighsyncd/neighsync.h

@@ -23,7 +23,7 @@ class NeighSync : public NetMsg
 public:
     enum { MAX_ADDR_SIZE = 64 };
 
-    NeighSync(RedisPipeline *pipelineAppDB, DBConnector *stateDb);
+    NeighSync(RedisPipeline *pipelineAppDB, DBConnector *stateDb, DBConnector *cfgDb);
     ~NeighSync();
 
     virtual void onMsg(int nlmsg_type, struct nl_object *obj);
@@ -39,6 +39,9 @@ class NeighSync : public NetMsg
     Table m_stateNeighRestoreTable;
     ProducerStateTable m_neighTable;
     AppRestartAssist  *m_AppRestartAssist;
+    Table m_cfgVlanInterfaceTable, m_cfgLagInterfaceTable, m_cfgInterfaceTable;
+
+    bool isLinkLocalEnabled(const std::string &port);
 };
 
 }

neighsyncd/neighsyncd.cpp

@@ -18,8 +18,9 @@ int main(int argc, char **argv)
     DBConnector appDb("APPL_DB", 0);
     RedisPipeline pipelineAppDB(&appDb);
     DBConnector stateDb("STATE_DB", 0);
+    DBConnector cfgDb("CONFIG_DB", 0);
 
-    NeighSync sync(&pipelineAppDB, &stateDb);
+    NeighSync sync(&pipelineAppDB, &stateDb, &cfgDb);
 
     NetDispatcher::getInstance().registerMessageHandler(RTM_NEWNEIGH, &sync);
     NetDispatcher::getInstance().registerMessageHandler(RTM_DELNEIGH, &sync);

orchagent/neighorch.cpp

@@ -513,6 +513,19 @@ void NeighOrch::doTask(Consumer &consumer)
 
         IpAddress ip_address(key.substr(found+1));
 
+        /* Verify Ipv4 LinkLocal and skip neighbor entry added for RFC5549 */
+        if ((ip_address.getAddrScope() == IpAddress::LINK_SCOPE) && (ip_address.isV4()))
+        {
+            /* Check if this prefix is not a configured ip, if so allow */
+            IpPrefix ipll_prefix(ip_address.getV4Addr(), 16);
+            if (!m_intfsOrch->isPrefixSubnet (ipll_prefix, alias))
+            {
+                SWSS_LOG_NOTICE("Skip IPv4LL neighbor %s, Intf:%s op: %s ", ip_address.to_string().c_str(), alias.c_str(), op.c_str());
+                it = consumer.m_toSync.erase(it);
+                continue;
+            }
+        }
+
         NeighborEntry neighbor_entry = { ip_address, alias };
 
         if (op == SET_COMMAND)

orchagent/routeorch.cpp

@@ -127,15 +127,15 @@ RouteOrch::RouteOrch(DBConnector *db, string tableName, SwitchOrch *switchOrch,
     IpPrefix linklocal_prefix = getLinkLocalEui64Addr();
 
     addLinkLocalRouteToMe(gVirtualRouterId, linklocal_prefix);
+    SWSS_LOG_NOTICE("Created link local ipv6 route %s to cpu", linklocal_prefix.to_string().c_str());
 
     /* Add fe80::/10 subnet route to forward all link-local packets
      * destined to us, to CPU */
     IpPrefix default_link_local_prefix("fe80::/10");
 
     addLinkLocalRouteToMe(gVirtualRouterId, default_link_local_prefix);
+    SWSS_LOG_NOTICE("Created link local ipv6 route %s to cpu", default_link_local_prefix.to_string().c_str());
 
-    /* TODO: Add the link-local fe80::/10 route to cpu in every VRF created from
-     * vrforch::addOperation. */
 }
 
 std::string RouteOrch::getLinkLocalEui64Addr(void)
@@ -205,6 +205,27 @@ void RouteOrch::addLinkLocalRouteToMe(sai_object_id_t vrf_id, IpPrefix linklocal
     SWSS_LOG_NOTICE("Created link local ipv6 route  %s to cpu", linklocal_prefix.to_string().c_str());
 }
 
+void RouteOrch::delLinkLocalRouteToMe(sai_object_id_t vrf_id, IpPrefix linklocal_prefix)
+{
+    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);
+    subnet(unicast_route_entry.destination, unicast_route_entry.destination);
+
+    sai_status_t status = sai_route_api->remove_route_entry(&unicast_route_entry);
+    if (status != SAI_STATUS_SUCCESS)
+    {
+        SWSS_LOG_ERROR("Failed to delete link local ipv6 route %s to cpu, rv:%d",
+                       linklocal_prefix.getIp().to_string().c_str(), status);
+        return;
+    }
+
+    gCrmOrch->decCrmResUsedCounter(CrmResourceType::CRM_IPV6_ROUTE);
+
+    SWSS_LOG_NOTICE("Deleted link local ipv6 route  %s to cpu", linklocal_prefix.to_string().c_str());
+}
+
 bool RouteOrch::hasNextHopGroup(const NextHopGroupKey& nexthops) const
 {
     return m_syncdNextHopGroups.find(nexthops) != m_syncdNextHopGroups.end();

orchagent/routeorch.h

@@ -121,6 +121,10 @@ class RouteOrch : public Orch, public Subject
     bool createFineGrainedNextHopGroup(sai_object_id_t &next_hop_group_id, vector<sai_attribute_t> &nhg_attrs);
     bool removeFineGrainedNextHopGroup(sai_object_id_t &next_hop_group_id);
 
+    void addLinkLocalRouteToMe(sai_object_id_t vrf_id, IpPrefix linklocal_prefix);
+    void delLinkLocalRouteToMe(sai_object_id_t vrf_id, IpPrefix linklocal_prefix);
+    std::string getLinkLocalEui64Addr(void);
+
 private:
     SwitchOrch *m_switchOrch;
     NeighOrch *m_neighOrch;
@@ -148,9 +152,6 @@ class RouteOrch : public Orch, public Subject
     bool addRoutePost(const RouteBulkContext& ctx, const NextHopGroupKey &nextHops);
     bool removeRoutePost(const RouteBulkContext& ctx);
 
-    std::string getLinkLocalEui64Addr(void);
-    void        addLinkLocalRouteToMe(sai_object_id_t vrf_id, IpPrefix linklocal_prefix);
-
     void doTask(Consumer& consumer);
 };