[FPMSYNCD] Evpn/Vxlan related changes to support FRR7.5(#1585)

1) With FRR7.5 upgrade Netlink Msg from FRR has NLA_F_NESTED flag set in
RTA_TYPE while sending VNI and RMAC.
2) In the new patch to keep it in line with FRR upstreaming, we are not
sending the VLAN ID from FRR as it can be extracted from ifindex inside
the nexthop information.

Author: kishorekunal01

fpmsyncd/fpmlink.cpp

@@ -18,6 +18,18 @@ void netlink_parse_rtattr(struct rtattr **tb, int max, struct rtattr *rta,
         {
             tb[rta->rta_type] = rta;
         }
+        else
+        {
+            /* FRR 7.5 is sending RTA_ENCAP with NLA_F_NESTED bit set*/
+            if (rta->rta_type & NLA_F_NESTED)
+            {
+                int rta_type = rta->rta_type & ~NLA_F_NESTED;
+                if (rta_type <= max)
+                {
+                   tb[rta_type] = rta;
+                }
+            }
+        }
         rta = RTA_NEXT(rta, len);
     }
 }

fpmsyncd/routesync.cpp

@@ -31,7 +31,6 @@ using namespace swss;
 
 #define VXLAN_VNI             0
 #define VXLAN_RMAC            1
-#define VXLAN_VLAN            2
 #define NH_ENCAP_VXLAN      100
 
 
@@ -93,7 +92,7 @@ void RouteSync::parseRtAttrNested(struct rtattr **tb, int max,
  *
  * Return:      void.
  */
-void RouteSync::parseEncap(struct rtattr *tb, uint32_t &encap_value, string &rmac, uint32_t &vlan)
+void RouteSync::parseEncap(struct rtattr *tb, uint32_t &encap_value, string &rmac)
 {
     struct rtattr *tb_encap[3] = {0};
     char mac_buf[MAX_ADDR_SIZE+1];
@@ -102,10 +101,9 @@ void RouteSync::parseEncap(struct rtattr *tb, uint32_t &encap_value, string &rma
     parseRtAttrNested(tb_encap, 3, tb);
     encap_value = *(uint32_t *)RTA_DATA(tb_encap[VXLAN_VNI]);
     memcpy(&mac_buf, RTA_DATA(tb_encap[VXLAN_RMAC]), MAX_ADDR_SIZE);
-    vlan = *(uint32_t *)RTA_DATA(tb_encap[VXLAN_VLAN]);
 
-    SWSS_LOG_INFO("Rx MAC %s VNI %d Vlan %d",
-        prefixMac2Str(mac_buf, mac_val, ETHER_ADDR_STRLEN), encap_value, vlan);
+    SWSS_LOG_INFO("Rx MAC %s VNI %d",
+        prefixMac2Str(mac_buf, mac_val, ETHER_ADDR_STRLEN), encap_value);
     rmac = mac_val;
 
     return;
@@ -125,9 +123,8 @@ void RouteSync::getEvpnNextHopSep(string& nexthops, string& vni_list,
 void RouteSync::getEvpnNextHopGwIf(char *gwaddr, int vni_value, 
                                string& nexthops, string& vni_list,  
                                string& mac_list, string& intf_list,
-                               string rmac, unsigned int vid)
+                               string rmac, string vlan_id)
 {
-    string vlan_id = "Vlan" + to_string(vid);
     nexthops+= gwaddr;
     vni_list+= to_string(vni_value);
     mac_list+=rmac;
@@ -148,7 +145,10 @@ bool RouteSync::getEvpnNextHop(struct nlmsghdr *h, int received_bytes,
     int gw_af;
     struct in6_addr ipv6_address;
     string rmac;
-    uint32_t vlan = 0;
+    string vlan;
+    int index;
+    char if_name[IFNAMSIZ] = "0";
+    char ifname_unknown[IFNAMSIZ] = "unknown";
 
     if (tb[RTA_GATEWAY])
         gate = RTA_DATA(tb[RTA_GATEWAY]);
@@ -189,6 +189,19 @@ bool RouteSync::getEvpnNextHop(struct nlmsghdr *h, int received_bytes,
 
             inet_ntop(gw_af, gateaddr, nexthopaddr, MAX_ADDR_SIZE);
 
+            if (tb[RTA_OIF])
+            {
+                index = *(int *)RTA_DATA(tb[RTA_OIF]);
+
+                /* If we cannot get the interface name */
+                if (!getIfName(index, if_name, IFNAMSIZ))
+                {
+                    strcpy(if_name, ifname_unknown);
+                }
+
+                vlan = if_name;
+            }
+
             if (tb[RTA_ENCAP_TYPE])
             {
                 encap = *(uint16_t *)RTA_DATA(tb[RTA_ENCAP_TYPE]);
@@ -197,12 +210,12 @@ bool RouteSync::getEvpnNextHop(struct nlmsghdr *h, int received_bytes,
             if (tb[RTA_ENCAP] && tb[RTA_ENCAP_TYPE]
                 && (*(uint16_t *)RTA_DATA(tb[RTA_ENCAP_TYPE]) == NH_ENCAP_VXLAN)) 
             {
-                parseEncap(tb[RTA_ENCAP], encap_value, rmac, vlan);
+                parseEncap(tb[RTA_ENCAP], encap_value, rmac);
             }
-            SWSS_LOG_DEBUG("Rx MsgType:%d Nexthop:%s encap:%d encap_value:%d rmac:%s vlan:%d", h->nlmsg_type,
-                            nexthopaddr, encap, encap_value, rmac.c_str(), vlan);
+            SWSS_LOG_DEBUG("Rx MsgType:%d Nexthop:%s encap:%d encap_value:%d rmac:%s vlan:%s", h->nlmsg_type,
+                            nexthopaddr, encap, encap_value, rmac.c_str(), vlan.c_str());
 
-            if (encap_value == 0 || vlan == 0 || MacAddress(rmac) == MacAddress("00:00:00:00:00:00"))
+            if (encap_value == 0 || !(vlan.compare(ifname_unknown)) || MacAddress(rmac) == MacAddress("00:00:00:00:00:00"))
             {
                 return false;
             }
@@ -270,6 +283,20 @@ bool RouteSync::getEvpnNextHop(struct nlmsghdr *h, int received_bytes,
 
                     inet_ntop(gw_af, gateaddr, nexthopaddr, MAX_ADDR_SIZE);
 
+
+                    if (rtnh->rtnh_ifindex)
+                    {
+                        index = rtnh->rtnh_ifindex;
+
+                        /* If we cannot get the interface name */
+                        if (!getIfName(index, if_name, IFNAMSIZ))
+                        {
+                            strcpy(if_name, ifname_unknown);
+                        }
+
+                        vlan = if_name;
+                    }
+
                     if (subtb[RTA_ENCAP_TYPE])
                     {
                         encap = *(uint16_t *)RTA_DATA(subtb[RTA_ENCAP_TYPE]);
@@ -278,12 +305,12 @@ bool RouteSync::getEvpnNextHop(struct nlmsghdr *h, int received_bytes,
                     if (subtb[RTA_ENCAP] && subtb[RTA_ENCAP_TYPE]
                         && (*(uint16_t *)RTA_DATA(subtb[RTA_ENCAP_TYPE]) == NH_ENCAP_VXLAN))
                     {
-                        parseEncap(subtb[RTA_ENCAP], encap_value, rmac, vlan);
+                        parseEncap(subtb[RTA_ENCAP], encap_value, rmac);
                     }
-                    SWSS_LOG_DEBUG("Multipath Nexthop:%s encap:%d encap_value:%d rmac:%s vlan:%d",
-                                    nexthopaddr, encap, encap_value, rmac.c_str(), vlan);
+                    SWSS_LOG_DEBUG("Multipath Nexthop:%s encap:%d encap_value:%d rmac:%s vlan:%s",
+                                    nexthopaddr, encap, encap_value, rmac.c_str(), vlan.c_str());
 
-                    if (encap_value == 0 || vlan == 0 || MacAddress(rmac) == MacAddress("00:00:00:00:00:00"))
+                    if (encap_value == 0 || !(vlan.compare(ifname_unknown)) || MacAddress(rmac) == MacAddress("00:00:00:00:00:00"))
                     {
                         return false;
                     }

fpmsyncd/routesync.h

@@ -41,7 +41,7 @@ class RouteSync : public NetMsg
     /* Handle regular route (include VRF route) */
     void onRouteMsg(int nlmsg_type, struct nl_object *obj, char *vrf);
 
-    void parseEncap(struct rtattr *tb, uint32_t &encap_value, string &rmac, uint32_t &vlan);
+    void parseEncap(struct rtattr *tb, uint32_t &encap_value, string &rmac);
 
     void parseRtAttrNested(struct rtattr **tb, int max,
                  struct rtattr *rta);
@@ -64,7 +64,7 @@ class RouteSync : public NetMsg
     void getEvpnNextHopGwIf(char *gwaddr, int vni_value,
                           string& nexthops, string& vni_list,
                           string& mac_list, string& intf_list,
-                          string rmac, unsigned int vid);
+                          string rmac, string vlan_id);
 
     bool getEvpnNextHop(struct nlmsghdr *h, int received_bytes, struct rtattr *tb[],
                         string& nexthops, string& vni_list, string& mac_list,