[VyOS] GRE tunnel implementation (#3566)

Author: ssasso

docs/plugins/tunnel.gre.md

@@ -11,6 +11,7 @@ The plugin includes Jinja2 templates for the following platforms:
 |--------------|:-:|:-:|:-:|
 | Cisco IOS/XE[^18v] |✅|✅|✅|
 | FRR                 |✅|✅|✅|
+| VyOS               |✅|✅|✅|
 
 [^18v]: Includes Cisco IOSv, Cisco IOSvL2, Cisco CSR 1000v, Cisco Catalyst 8000v, Cisco IOS-on-Linux (IOL), and IOL Layer-2 image.
 

netsim/ansible/templates/initial/vyos.j2

@@ -13,6 +13,9 @@ set system host-name 'vyos-{{ inventory_hostname | replace("_","-") }}'
 {% if vlans is defined %}
 {% include 'vyos.vlan.j2' %}
 {% endif %}
+{% for x_dp in config|default([]) %}
+{%  include x_dp + '/vyos.initial.j2' ignore missing %}
+{% endfor %}
 
 {% if loopback.ipv4 is defined %}
 set interfaces dummy dum0 address {{ loopback.ipv4 }}
@@ -36,6 +39,8 @@ set interfaces dummy dum0 address {{ loopback.ipv6 }}
 {%     set ns.iface_level = "dummy" %}
 {%   elif l.ifname.startswith('bond') %}
 {%     set ns.iface_level = "bonding" %}
+{%   elif l.ifname.startswith('tun') %}
+{%     set ns.iface_level = "tunnel" %}
 {%   endif %}
 {#
 # Split interface name with vif, if needed

netsim/devices/vyos.yml

@@ -3,6 +3,7 @@ description: VyOS VM/container
 interface_name: eth{ifindex}
 loopback_interface_name: "dum{ifindex}"
 lag_interface_name: "bond{lag.ifindex}"
+tunnel_interface_name: "tun{ifindex}"
 mgmt_if: eth0
 libvirt:
   image: vyos/current
@@ -81,6 +82,8 @@ features:
       vrf: True
       inter_vrf: True
       discard: True
+  tunnel:
+    gre: [ vrf ]
   vlan:
     model: l3-switch
     svi_interface_name: "br0.{vlan}"

netsim/extra/tunnel.gre/vyos.initial.j2

@@ -0,0 +1,16 @@
+{# Initial VyOS GRE tunnel implementation needs to be tackled here,
+   otherwise it will be impossible to use the tunnel interface by other modules.
+#}
+{% for intf in netlab_interfaces if intf.tunnel.mode|default('') in ['gre'] %}
+
+# In VyOS, GRE tunnels can be established over both IPv4 (encapsulation gre) and IPv6 (encapsulation ip6gre) transport networks.
+
+set interfaces tunnel {{ intf.ifname }} encapsulation 'gre'
+{%   if intf.tunnel.af == 'ipv6' %}
+set interfaces tunnel {{ intf.ifname }} encapsulation 'ip6gre'
+{%   endif %}
+
+set interfaces tunnel {{ intf.ifname }} source-address {{ intf.tunnel._source[intf.tunnel.af] }}
+set interfaces tunnel {{ intf.ifname }} remote {{ intf.tunnel._destination[intf.tunnel.af] }}
+
+{% endfor %}

netsim/extra/tunnel.gre/vyos.j2

@@ -0,0 +1,6 @@
+{% for intf in netlab_interfaces if intf.tunnel.mode|default('') in ['gre'] %}
+
+# Source interface will also be responsible for outer VRF selection, if any.
+set interfaces tunnel {{ intf.ifname }} source-interface {{ intf.tunnel._source.ifname }}
+
+{% endfor %}