vxlan: T2172: add source-address option

This is a base requirement for l2vpn evpn. When source-address is configured,
the option "local <source-addr> nolearning" is appended when creating the
interface as mentioned here: https://vincent.bernat.ch/en/blog/2017-vxlan-bgp-evpn

3 files changed, 37 insertions, 12 deletions

diff --git a/interface-definitions/interfaces-vxlan.xml.in b/interface-definitions/interfaces-vxlan.xml.in
index 5dcaf065c..fdde57525 100644
--- a/interface-definitions/interfaces-vxlan.xml.in
+++ b/interface-definitions/interfaces-vxlan.xml.in
@@ -52,6 +52,18 @@
               #include <include/ipv6-dup-addr-detect-transmits.xml.i>
             </children>
           </node>
+          <leafNode name="source-address">
+            <properties>
+              <help>VXLAN source address</help>
+              <valueHelp>
+                <format>ipv4</format>
+                <description>IPv4 source-address of VXLAN tunnel</description>
+              </valueHelp>
+              <constraint>
+                <validator name="ipv4-address"/>
+              </constraint>
+            </properties>
+          </leafNode>
           <leafNode name="source-interface">
             <properties>
               <help>Physical Interface used for this connection</help>
diff --git a/python/vyos/ifconfig/vxlan.py b/python/vyos/ifconfig/vxlan.py
index 5678ad62e..f47ae17cc 100644
--- a/python/vyos/ifconfig/vxlan.py
+++ b/python/vyos/ifconfig/vxlan.py
@@ -43,12 +43,13 @@ class VXLANIf(Interface):
 
     default = {
         'type': 'vxlan',
-        'vni': 0,
-        'dev': '',
         'group': '',
-        'remote': '',
         'port': 8472,   # The Linux implementation of VXLAN pre-dates
                         # the IANA's selection of a standard destination port
+        'remote': '',
+        'src_address': '',
+        'src_interface': '',
+        'vni': 0
     }
     definition = {
         **Interface.definition,
@@ -58,24 +59,30 @@ class VXLANIf(Interface):
             'bridgeable': True,
         }
     }
-    options = ['group', 'remote', 'dev', 'port', 'vni']
+    options = ['group', 'remote', 'src_interface', 'port', 'vni', 'src_address']
 
     mapping = {
         'ifname': 'add',
         'vni':    'id',
         'port':   'dstport',
+        'src_address': 'nolearning local',
     }
 
     def _create(self):
         cmdline = set()
         if self.config['remote']:
-            cmdline = ('ifname', 'type', 'remote', 'dev', 'vni', 'port')
-        elif self.config['group'] and self.config['dev']:
-            cmdline = ('ifname', 'type', 'group', 'dev', 'vni', 'port')
+            cmdline = ('ifname', 'type', 'remote', 'src_interface', 'vni', 'port')
+
+        elif self.config['src_address']:
+            cmdline = ('ifname', 'type', 'src_address', 'vni', 'port')
+
+        elif self.config['group'] and self.config['src_interface']:
+            cmdline = ('ifname', 'type', 'group', 'src_interface', 'vni', 'port')
+
         else:
-            intf = self.config['intf']
+            ifname = self.config['ifname']
             raise ConfigError(
-                f'VXLAN "{intf}" is missing mandatory underlay interface for a multicast network.')
+                f'VXLAN "{ifname}" is missing mandatory underlay interface for a multicast network.')
 
         cmd = 'ip link'
         for key in cmdline:
diff --git a/src/conf_mode/interfaces-vxlan.py b/src/conf_mode/interfaces-vxlan.py
index ba0f9a61a..6639a9b0d 100755
--- a/src/conf_mode/interfaces-vxlan.py
+++ b/src/conf_mode/interfaces-vxlan.py
@@ -42,6 +42,7 @@ default_config_data = {
     'ipv6_eui64_prefix': '',
     'ipv6_forwarding': 1,
     'ipv6_dup_addr_detect': 1,
+    'source_address': '',
     'source_interface': '',
     'mtu': 1450,
     'remote': '',
@@ -124,6 +125,10 @@ def get_config():
     if conf.exists('ipv6 dup-addr-detect-transmits'):
         vxlan['ipv6_dup_addr_detect'] = int(conf.return_value('ipv6 dup-addr-detect-transmits'))
 
+    # VXLAN source address
+    if conf.exists('source-address'):
+        vxlan['source_address'] = conf.return_value('source-address')
+
     # VXLAN underlay interface
     if conf.exists('source-interface'):
         vxlan['source_interface'] = conf.return_value('source-interface')
@@ -168,8 +173,8 @@ def verify(vxlan):
         if not vxlan['source_interface'] in interfaces():
             raise ConfigError('VXLAN source interface does not exist')
 
-    if not (vxlan['group'] or vxlan['remote']):
-        raise ConfigError('Group or remote must be configured')
+    if not (vxlan['group'] or vxlan['remote'] or vxlan['source_address']):
+        raise ConfigError('Group, remote or source-address must be configured')
 
     if not vxlan['vni']:
         raise ConfigError('Must configure VNI for VXLAN')
@@ -206,7 +211,8 @@ def apply(vxlan):
         # Assign VXLAN instance configuration parameters to config dict
         conf['vni'] = vxlan['vni']
         conf['group'] = vxlan['group']
-        conf['dev'] = vxlan['source_interface']
+        conf['src_address'] = vxlan['source_address']
+        conf['src_interface'] = vxlan['source_interface']
         conf['remote'] = vxlan['remote']
         conf['port'] = vxlan['remote_port']