server: support injecting multipath to zebra

Signed-off-by: ISHIDA Wataru <ishida.wataru@lab.ntt.co.jp>

3 files changed, 133 insertions, 9 deletions

diff --git a/server/zclient.go b/server/zclient.go
index 1b37e5db..6da629c3 100644
--- a/server/zclient.go
+++ b/server/zclient.go
@@ -28,14 +28,23 @@ import (
 	"strings"
 )
 
-func newIPRouteMessage(path *table.Path) *zebra.Message {
-	if path == nil || path.IsFromExternal() {
+func newIPRouteMessage(dst []*table.Path) *zebra.Message {
+	paths := make([]*table.Path, 0, len(dst))
+	for _, path := range dst {
+		if path == nil || path.IsFromExternal() {
+			continue
+		}
+		paths = append(paths, path)
+	}
+	if len(paths) == 0 {
 		return nil
 	}
+	path := paths[0]
+
 	l := strings.SplitN(path.GetNlri().String(), "/", 2)
 	var command zebra.API_TYPE
 	var prefix net.IP
-	nexthops := []net.IP{}
+	nexthops := make([]net.IP, 0, len(paths))
 	switch path.GetRouteFamily() {
 	case bgp.RF_IPv4_UC:
 		if path.IsWithdraw == true {
@@ -44,7 +53,9 @@ func newIPRouteMessage(path *table.Path) *zebra.Message {
 			command = zebra.IPV4_ROUTE_ADD
 		}
 		prefix = net.ParseIP(l[0]).To4()
-		nexthops = append(nexthops, path.GetNexthop().To4())
+		for _, p := range paths {
+			nexthops = append(nexthops, p.GetNexthop().To4())
+		}
 	case bgp.RF_IPv6_UC:
 		if path.IsWithdraw == true {
 			command = zebra.IPV6_ROUTE_DELETE
@@ -52,11 +63,12 @@ func newIPRouteMessage(path *table.Path) *zebra.Message {
 			command = zebra.IPV6_ROUTE_ADD
 		}
 		prefix = net.ParseIP(l[0]).To16()
-		nexthops = append(nexthops, path.GetNexthop().To16())
+		for _, p := range paths {
+			nexthops = append(nexthops, p.GetNexthop().To16())
+		}
 	default:
 		return nil
 	}
-
 	flags := uint8(zebra.MESSAGE_NEXTHOP)
 	plen, _ := strconv.Atoi(l[1])
 	med, err := path.GetMed()
@@ -203,9 +215,17 @@ func (w *zebraWatcher) loop() error {
 			}
 		case ev := <-w.ch:
 			msg := ev.(*watcherEventBestPathMsg)
-			for _, path := range msg.pathList {
-				if m := newIPRouteMessage(path); m != nil {
-					w.client.Send(m)
+			if table.UseMultiplePaths.Enabled {
+				for _, dst := range msg.multiPathList {
+					if m := newIPRouteMessage(dst); m != nil {
+						w.client.Send(m)
+					}
+				}
+			} else {
+				for _, path := range msg.pathList {
+					if m := newIPRouteMessage([]*table.Path{path}); m != nil {
+						w.client.Send(m)
+					}
 				}
 			}
 		}
diff --git a/test/lib/gobgp.py b/test/lib/gobgp.py
index cf72b721..07b2c8b0 100644
--- a/test/lib/gobgp.py
+++ b/test/lib/gobgp.py
@@ -237,6 +237,10 @@ class GoBGPContainer(BGPContainer):
                     },
                 },
         }}
+
+        if self.zebra:
+            config['global']['use-multiple-paths'] = {'config': {'enabled': True}}
+
         for peer, info in self.peers.iteritems():
             afi_safi_list = []
             version = netaddr.IPNetwork(info['neigh_addr']).version
diff --git a/test/scenario_test/bgp_zebra_test.py b/test/scenario_test/bgp_zebra_test.py
index 7a024534..6b33a9f9 100644
--- a/test/scenario_test/bgp_zebra_test.py
+++ b/test/scenario_test/bgp_zebra_test.py
@@ -176,6 +176,106 @@ class GoBGPTestBase(unittest.TestCase):
         o2.add_static_route(self.bridges['br02_v6'].subnet, next_hop)
         g1.get_reachablily('2001:30::2')
 
+    def test_07_mpath_test_setup(self):
+        g1 = GoBGPContainer(name='g1', asn=65000, router_id='192.168.0.1',
+                            ctn_image_name=parser_option.gobgp_image,
+                            log_level=parser_option.gobgp_log_level,
+                            config_format=parser_option.config_format,
+                            zebra=True)
+        g2 = GoBGPContainer(name='g2', asn=65001, router_id='192.168.0.2')
+        g3 = GoBGPContainer(name='g3', asn=65001, router_id='192.168.0.3')
+        g4 = GoBGPContainer(name='g4', asn=65000, router_id='192.168.0.4')
+        g5 = GoBGPContainer(name='g5', asn=65000, router_id='192.168.0.5')
+
+        ctns = [g1, g2, g3, g4, g5]
+        for ctn in ctns:
+            self.ctns[ctn.name] = ctn
+
+        initial_wait_time = max(ctn.run() for ctn in ctns)
+
+        time.sleep(initial_wait_time)
+
+        # advertise same prefix
+        g2.add_route('10.0.10.0/24')
+        g3.add_route('10.0.10.0/24')
+        g4.add_route('10.0.10.0/24')
+        g5.add_route('10.0.10.0/24')
+
+        for g in [g2, g3, g4, g5]:
+            g1.add_peer(g)
+            g.add_peer(g1)
+
+    def test_08_mpath_test_check_neighbor_established(self):
+        g1 = self.ctns['g1']
+        g2 = self.ctns['g2']
+        g3 = self.ctns['g3']
+        g4 = self.ctns['g4']
+        g5 = self.ctns['g5']
+        for g in [g2, g3, g4, g5]:
+            g1.wait_for(expected_state=BGP_FSM_ESTABLISHED, peer=g)
+        time.sleep(3)
+
+    def test_09_mpath_test_check_mpath_injected(self):
+        g1 = self.ctns['g1']
+        g2 = self.ctns['g2']
+        g3 = self.ctns['g3']
+        g4 = self.ctns['g4']
+        g5 = self.ctns['g5']
+
+        def nexthops():
+            n = []
+            for line in g1.local('ip route show 10.0.10.0/24', capture=True).split('\n'):
+                line = line.strip()
+                if 'via' in line:
+                    n.append(line.split(' ')[2].strip())
+            return n
+
+        nhs = nexthops()
+        self.assertTrue(len(nhs) == 2)
+        self.assertTrue(g1.peers[g4]['neigh_addr'].split('/')[0] in nhs)
+        self.assertTrue(g1.peers[g5]['neigh_addr'].split('/')[0] in nhs)
+
+        g4.local('gobgp g ri del 10.0.10.0/24')
+        time.sleep(3)
+
+        nhs = nexthops()
+        self.assertTrue(len(nhs) == 1)
+        self.assertTrue(g1.peers[g5]['neigh_addr'].split('/')[0] in nhs)
+
+        g4.local('gobgp g ri add 10.0.10.0/24 local-pref 200')
+        time.sleep(3)
+
+        nhs = nexthops()
+        self.assertTrue(len(nhs) == 1)
+        self.assertTrue(g1.peers[g4]['neigh_addr'].split('/')[0] in nhs)
+
+        g4.local('gobgp g ri del 10.0.10.0/24')
+        g5.local('gobgp g ri del 10.0.10.0/24')
+        time.sleep(3)
+
+        nhs = nexthops()
+        self.assertTrue(len(nhs) == 2)
+        self.assertTrue(g1.peers[g2]['neigh_addr'].split('/')[0] in nhs)
+        self.assertTrue(g1.peers[g3]['neigh_addr'].split('/')[0] in nhs)
+
+        g3.local('gobgp g ri del 10.0.10.0/24')
+        time.sleep(3)
+
+        nhs = nexthops()
+        self.assertTrue(len(nhs) == 1)
+        self.assertTrue(g1.peers[g2]['neigh_addr'].split('/')[0] in nhs)
+
+        g3.local('gobgp g ri add 10.0.10.0/24 med 10')
+
+        nhs = nexthops()
+        self.assertTrue(len(nhs) == 1)
+        self.assertTrue(g1.peers[g2]['neigh_addr'].split('/')[0] in nhs)
+
+        g2.local('gobgp g ri add 10.0.10.0/24 med 20')
+
+        nhs = nexthops()
+        self.assertTrue(len(nhs) == 1)
+        self.assertTrue(g1.peers[g3]['neigh_addr'].split('/')[0] in nhs)
 
 if __name__ == '__main__':
     if os.geteuid() is not 0: