Merge pull request #17580 from varuntumbe/dev/label_pool_release_fix

BGP Labelpool : Releasing the label in labelpool when VPN session gets removed

9 files changed, 463 insertions, 19 deletions

diff --git a/bgpd/bgp_mplsvpn.c b/bgpd/bgp_mplsvpn.c
index 85cc8f3596..b96c287f86 100644
--- a/bgpd/bgp_mplsvpn.c
+++ b/bgpd/bgp_mplsvpn.c
@@ -4079,6 +4079,35 @@ void bgp_vpn_leak_export(struct bgp *from_bgp)
 	}
 }
 
+/* It releases the label from labelpool which
+ * was previously assigned and unsets the flag based on reset arg
+ * This also used in vty to release the label and to change the allocation mode as well
+ */
+void bgp_vpn_release_label(struct bgp *bgp, afi_t afi, bool reset)
+{
+	if (!CHECK_FLAG(bgp->vpn_policy[afi].flags, BGP_VPN_POLICY_TOVPN_LABEL_AUTO))
+		return;
+	/*
+	 * label has previously been automatically
+	 * assigned by labelpool: release it
+	 *
+	 * NB if tovpn_label == MPLS_LABEL_NONE it
+	 * means the automatic assignment is in flight
+	 * and therefore the labelpool callback must
+	 * detect that the auto label is not needed.
+	 */
+	if (bgp->vpn_policy[afi].tovpn_label == MPLS_LABEL_NONE)
+		return;
+	if (CHECK_FLAG(bgp->vpn_policy[afi].flags, BGP_VPN_POLICY_TOVPN_LABEL_PER_NEXTHOP))
+		return;
+
+	bgp_lp_release(LP_TYPE_VRF, &bgp->vpn_policy[afi], bgp->vpn_policy[afi].tovpn_label);
+	bgp->vpn_policy[afi].tovpn_label = MPLS_LABEL_NONE;
+
+	if (reset)
+		UNSET_FLAG(bgp->vpn_policy[afi].flags, BGP_VPN_POLICY_TOVPN_LABEL_AUTO);
+}
+
 /* The nexthops values are compared to
  * find in the tree the appropriate cache entry
  */
diff --git a/bgpd/bgp_mplsvpn.h b/bgpd/bgp_mplsvpn.h
index 39fed66781..18639fc69b 100644
--- a/bgpd/bgp_mplsvpn.h
+++ b/bgpd/bgp_mplsvpn.h
@@ -352,6 +352,7 @@ extern void vpn_handle_router_id_update(struct bgp *bgp, bool withdraw,
 					bool is_config);
 extern void bgp_vpn_leak_unimport(struct bgp *from_bgp);
 extern void bgp_vpn_leak_export(struct bgp *from_bgp);
+extern void bgp_vpn_release_label(struct bgp *bgp, afi_t afi, bool reset);
 
 extern bool bgp_mplsvpn_path_uses_valid_mpls_label(struct bgp_path_info *pi);
 extern int
diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
index 22fbb1bb21..e336b54eb4 100644
--- a/bgpd/bgp_vty.c
+++ b/bgpd/bgp_vty.c
@@ -9948,26 +9948,9 @@ DEFPY (af_label_vpn_export,
 		UNSET_FLAG(bgp->vpn_policy[afi].flags,
 			   BGP_VPN_POLICY_TOVPN_LABEL_MANUAL_REG);
 
-	} else if (CHECK_FLAG(bgp->vpn_policy[afi].flags,
-			      BGP_VPN_POLICY_TOVPN_LABEL_AUTO)) {
+	} else if (CHECK_FLAG(bgp->vpn_policy[afi].flags, BGP_VPN_POLICY_TOVPN_LABEL_AUTO))
 		/* release any previous auto label */
-		if (bgp->vpn_policy[afi].tovpn_label != MPLS_LABEL_NONE) {
-
-			/*
-			 * label has previously been automatically
-			 * assigned by labelpool: release it
-			 *
-			 * NB if tovpn_label == MPLS_LABEL_NONE it
-			 * means the automatic assignment is in flight
-			 * and therefore the labelpool callback must
-			 * detect that the auto label is not needed.
-			 */
-
-			bgp_lp_release(LP_TYPE_VRF,
-				       &bgp->vpn_policy[afi],
-				       bgp->vpn_policy[afi].tovpn_label);
-		}
-	}
+		bgp_vpn_release_label(bgp, afi, false);
 
 	if (yes) {
 		if (label_auto) {
diff --git a/bgpd/bgpd.c b/bgpd/bgpd.c
index a244e15fb8..74f79cdd72 100644
--- a/bgpd/bgpd.c
+++ b/bgpd/bgpd.c
@@ -4037,6 +4037,9 @@ int bgp_delete(struct bgp *bgp)
 
 	bgp_vpn_leak_unimport(bgp);
 
+	bgp_vpn_release_label(bgp, AFI_IP, true);
+	bgp_vpn_release_label(bgp, AFI_IP6, true);
+
 	hook_call(bgp_inst_delete, bgp);
 
 	FOREACH_AFI_SAFI (afi, safi)
diff --git a/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/__init__.py b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/__init__.py
diff --git a/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r1/frr.conf b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r1/frr.conf
new file mode 100644
index 0000000000..7daf335aab
--- /dev/null
+++ b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r1/frr.conf
@@ -0,0 +1,117 @@
+interface r1-eth1 vrf vrf1
+ ip address 173.31.1.1/32
+!
+interface r1-eth2 vrf vrf2
+ ip address 173.31.1.2/32
+!
+interface r1-eth3 vrf vrf3
+ ip address 173.31.1.3/32
+!
+interface r1-eth4 vrf vrf4
+ ip address 173.31.1.4/32
+!
+interface r1-eth5 vrf vrf5
+ ip address 173.31.1.5/32
+!
+
+interface r1-eth0
+ ip address 192.168.0.1/24
+!
+
+interface r1-eth6
+ ip address 193.170.0.1/24
+
+interface lo
+ ip address 11.11.11.11/32
+!
+router ospf
+ ospf router-id 11.11.11.11
+ network 193.170.0.0/24 area 0.0.0.0
+ network 11.11.11.11/32 area 0.0.0.0
+ redistribute connected
+exit
+!
+mpls ldp
+ router-id 11.11.11.11
+ !
+ address-family ipv4
+  discovery transport-address 11.11.11.11
+  !
+  interface r1-eth6
+  exit
+  !
+ exit-address-family
+ !
+exit
+!
+bgp route-map delay-timer 1
+router bgp 65500
+ bgp router-id 192.0.2.1
+ no bgp ebgp-requires-policy
+ neighbor 192.168.0.2 remote-as 65501
+ address-family ipv4 unicast
+  no neighbor 192.168.0.2 activate
+ exit-address-family
+ address-family ipv4 vpn
+  neighbor 192.168.0.2 activate
+ exit-address-family
+!
+router bgp 65500 vrf vrf1
+ bgp router-id 192.0.2.1
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:1
+  rt vpn both 53:1
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65500 vrf vrf2
+ bgp router-id 192.0.2.1
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:2
+  rt vpn both 53:2
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65500 vrf vrf3
+ bgp router-id 192.0.2.1
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:3
+  rt vpn both 53:3
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65500 vrf vrf4
+ bgp router-id 192.0.2.1
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:4
+  rt vpn both 53:4
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65500 vrf vrf5
+ bgp router-id 192.0.2.1
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:5
+  rt vpn both 53:5
+  export vpn
+  import vpn
+ exit-address-family
+!
+
+interface r1-eth0
+ mpls bgp forwarding
+!
\ No newline at end of file
diff --git a/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r2/frr.conf b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r2/frr.conf
new file mode 100644
index 0000000000..6facebe40e
--- /dev/null
+++ b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r2/frr.conf
@@ -0,0 +1,88 @@
+interface r2-eth1 vrf vrf1
+ ip address 173.31.0.1/32
+!
+interface r2-eth2 vrf vrf2
+ ip address 173.31.0.2/32
+!
+interface r2-eth3 vrf vrf3
+ ip address 173.31.0.3/32
+!
+interface r2-eth4 vrf vrf4
+ ip address 173.31.0.4/32
+!
+interface r2-eth5 vrf vrf5
+ ip address 173.31.0.5/32
+!
+interface r2-eth0
+ ip address 192.168.0.2/24
+!
+router bgp 65501
+ bgp router-id 192.0.2.2
+ no bgp ebgp-requires-policy
+ neighbor 192.168.0.1 remote-as 65500
+ address-family ipv4 unicast
+  no neighbor 192.168.0.1 activate
+ exit-address-family
+ address-family ipv4 vpn
+  neighbor 192.168.0.1 activate
+ exit-address-family
+!
+router bgp 65501 vrf vrf1
+ bgp router-id 192.0.2.2
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:1
+  rt vpn both 53:1
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65501 vrf vrf2
+ bgp router-id 192.0.2.2
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:2
+  rt vpn both 53:2
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65501 vrf vrf3
+ bgp router-id 192.0.2.2
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:3
+  rt vpn both 53:3
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65501 vrf vrf4
+ bgp router-id 192.0.2.2
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:4
+  rt vpn both 53:4
+  export vpn
+  import vpn
+ exit-address-family
+!
+router bgp 65501 vrf vrf5
+ bgp router-id 192.0.2.2
+ address-family ipv4 unicast
+  redistribute connected
+  label vpn export auto
+  rd vpn export 445:5
+  rt vpn both 53:5
+  export vpn
+  import vpn
+ exit-address-family
+!
+
+interface r2-eth0
+ mpls bgp forwarding
+!
diff --git a/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r3/frr.conf b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r3/frr.conf
new file mode 100644
index 0000000000..8f49cdfe0c
--- /dev/null
+++ b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/r3/frr.conf
@@ -0,0 +1,32 @@
+interface r3-eth0
+ ip address 193.170.0.2/24
+!
+interface lo
+ ip address 33.33.33.33/32
+!
+interface r3-eth1
+ ip address 180.170.0.2/32
+!
+interface r3-eth2
+ ip address 180.170.0.3/32
+!
+router ospf
+ ospf router-id 33.33.33.33
+ network 193.170.0.0/24 area 0.0.0.0
+ network 33.33.33.33/32 area 0.0.0.0
+ redistribute connected
+exit
+!
+mpls ldp
+ router-id 33.33.33.33
+ !
+ address-family ipv4
+  discovery transport-address 33.33.33.33
+  !
+  interface r3-eth0
+  exit
+  !
+ exit-address-family
+ !
+exit
+!
\ No newline at end of file
diff --git a/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/test_bgp_vpnv4_vpn_auto.py b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/test_bgp_vpnv4_vpn_auto.py
new file mode 100644
index 0000000000..ed3cdca2f9
--- /dev/null
+++ b/tests/topotests/bgp_vpnv4_ebgp_vpn_auto/test_bgp_vpnv4_vpn_auto.py
@@ -0,0 +1,191 @@
+#!/usr/bin/env python
+# SPDX-License-Identifier: ISC
+
+#
+# test_bgp_vpnv4_vpn_auto.py
+#
+# Copyright (c) 2024 by Varun Hegde
+#
+
+"""
+ test_bgp_vpnv4_vpn_auto.py: Test the FRR BGP daemon with BGP VPN session with label export auto
+"""
+
+import os
+import sys
+import json
+import functools
+import pytest
+
+# Save the Current Working Directory to find configuration files.
+CWD = os.path.dirname(os.path.realpath(__file__))
+sys.path.append(os.path.join(CWD, "../"))
+
+# pylint: disable=C0413
+# Import topogen and topotest helpers
+from lib import topotest
+from lib.bgpcheck import (
+    check_show_bgp_vpn_prefix_found,
+    check_show_bgp_vpn_prefix_not_found,
+)
+from lib.topogen import Topogen, TopoRouter, get_topogen
+from lib.topolog import logger
+
+# Required to instantiate the topology builder class.
+
+
+pytestmark = [pytest.mark.bgpd]
+
+
+def build_topo(tgen):
+    "Build function"
+
+    # Create 3 routers.
+    tgen.add_router("r1")
+    tgen.add_router("r2")
+    tgen.add_router("r3")
+
+
+    for i in range(6):
+        switch = tgen.add_switch("s{0}".format(i))
+        switch.add_link(tgen.gears["r1"])
+        switch.add_link(tgen.gears["r2"])
+
+    #create a singiluar link between R2 -- R3
+    switch = tgen.add_switch("s6")
+    switch.add_link(tgen.gears["r1"])
+    switch.add_link(tgen.gears["r3"])
+
+    for i in range(7, 9):
+        switch = tgen.add_switch("s{0}".format(i))
+        switch.add_link(tgen.gears["r3"])
+
+
+
+def _populate_iface():
+    tgen = get_topogen()
+    cmds_list = [
+        "ip link add vrf{} type vrf table {}",
+        "ip link set dev vrf{} up",
+        "ip link set dev r1-eth{} master vrf{}",
+        "echo 1 > /proc/sys/net/mpls/conf/r1-eth{}/input",
+    ]
+    cmds_list2 = [
+        "ip link add vrf{} type vrf table {}",
+        "ip link set dev vrf{} up",
+        "ip link set dev r2-eth{} master vrf{}",
+        "echo 1 > /proc/sys/net/mpls/conf/r2-eth{}/input",
+    ]
+
+    for i in range(1, 6):
+        for cmd in cmds_list:
+            input = cmd.format(i, i)
+            logger.info("input: " + cmd)
+            output = tgen.net["r1"].cmd(cmd.format(i, i))
+            logger.info("output: " + output)
+
+        for cmd in cmds_list2:
+            input = cmd.format(i, i)
+            logger.info("input: " + cmd)
+            output = tgen.net["r2"].cmd(cmd.format(i, i))
+            logger.info("output: " + output)
+
+def setup_module(mod):
+    "Sets up the pytest environment"
+    tgen = Topogen(build_topo, mod.__name__)
+    tgen.start_topology()
+
+    router_list = tgen.routers()
+    _populate_iface()
+
+    for rname, router in router_list.items():
+        router.load_frr_config(os.path.join(CWD, "{}/frr.conf".format(rname)))
+
+    # Initialize all routers.
+    tgen.start_router()
+
+
+def teardown_module(_mod):
+    "Teardown the pytest environment"
+    tgen = get_topogen()
+
+    tgen.stop_topology()
+
+
+def test_labelpool_release():
+    """
+    Check that once we remove BGP VPN sesson
+    label pool structure ( allocated_map ) gets released properly or not
+    """
+    tgen = get_topogen()
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    # Just waiting for BGP VPN session to converge
+    logger.info("Waiting for BGP VPN sessions to converge and label pools to get initialised")
+    router = tgen.gears["r1"]
+
+    def _bgp_converge():
+        output = json.loads(
+            router.vtysh_cmd("show bgp labelpool summary json")
+        )
+        expected = {"ledger":5,"inUse":5,"requests":0,"labelChunks":1,"pending":0,"reconnects":1}
+        return topotest.json_cmp(output, expected)
+
+    test_func = functools.partial(_bgp_converge)
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
+    assert result is None, "Failed to see BGP Labelpool initialised"
+
+
+    # checking the initial label pool chunk's free labels
+    logger.info("checking the initial label pool chunk's free labels")
+    expected = [{"first":80,"last":207,"size":128,"numberFree":123}]
+    test_func = functools.partial(
+        topotest.router_json_cmp,
+        router,
+        "show bgp label chunks json",
+        expected,
+    )
+
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
+    assertmsg = '"{}" JSON output mismatches'.format(router.name)
+    assert result is None, assertmsg
+
+
+    # Test case : check whether label got released or not
+    logger.info(
+        "Remove multiple vpn session and check whether label got released or no"
+    )
+    router.vtysh_cmd(
+        """
+        configure terminal
+        no router bgp 65500 vrf vrf1
+        no router bgp 65500 vrf vrf2
+        """
+    )
+    expected = [{"first":80,"last":207,"size":128,"numberFree":125}]
+    test_func = functools.partial(
+        topotest.router_json_cmp,
+        router,
+        "show bgp label chunks json",
+        expected,
+    )
+
+    _, result = topotest.run_and_expect(test_func, None, count=30, wait=1)
+    assertmsg = '"{}" JSON output mismatches'.format(router.name)
+    assert result is None, assertmsg
+
+
+
+def test_memory_leak():
+    "Run the memory leak test and report results."
+    tgen = get_topogen()
+    if not tgen.is_memleak_enabled():
+        pytest.skip("Memory leak test/report is disabled")
+
+    tgen.report_memory_leaks()
+
+
+if __name__ == "__main__":
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))