[subnet decap] Fix VLAN prefix decap term (sonic-net#19229)

Why I did it
If subnet decap is enabled on T0, the subnet decap term should be created for VLAN prefixes.

Work item tracking
Microsoft ADO (number only): 28316828

How I did it
For VLAN prefixes, if subnet decap is enabled, created MP2MP decap terms with subnet type vlan and under the subnet decap tunnels.

Signed-off-by: Longxiang Lyu <[email protected]>

Author: lolyu

dockers/docker-orchagent/ipinip.json.j2

@@ -3,6 +3,8 @@
 {% else %}
 {% set ipv4_addresses = [] %}
 {% set ipv6_addresses = [] %}
+{% set ipv4_vlan_addresses = [] %}
+{% set ipv6_vlan_addresses = [] %}
 {% set ipv4_loopback_addresses = [] %}
 {% set ipv6_loopback_addresses = [] %}
 {% if DEVICE_METADATA['localhost']['sub_role'] == 'FrontEnd' or  DEVICE_METADATA['localhost']['sub_role'] == 'BackEnd'%}
@@ -44,12 +46,14 @@
 {% endfor %}
 {% for (name, prefix) in VLAN_INTERFACE|pfx_filter %}
     {%- if prefix | ipv4 %}
-        {%- set ipv4_addresses = ipv4_addresses.append(prefix) %}
+        {%- set ipv4_vlan_addresses = ipv4_vlan_addresses.append(prefix) %}
     {%- endif %}
     {%- if prefix | ipv6 %}
-        {%- set ipv6_addresses = ipv6_addresses.append(prefix) %}
+        {%- set ipv6_vlan_addresses = ipv6_vlan_addresses.append(prefix) %}
     {%- endif %}
 {% endfor %}
+{%- set ipv4_addresses = ipv4_addresses + ipv4_vlan_addresses %}
+{%- set ipv6_addresses = ipv6_addresses + ipv6_vlan_addresses %}
 [
 {% if ipv4_loopback_addresses %}
 {% if subnet_decap.enable %}
@@ -66,6 +70,15 @@
         },
         "OP": "SET"
     },
+{% for prefix in ipv4_vlan_addresses|sort %}
+    {
+        "TUNNEL_DECAP_TERM_TABLE:IPINIP_SUBNET:{{ prefix | network }}/{{ prefix | prefixlen }}" : {
+            "term_type":"MP2MP",
+            "subnet_type": "vlan"
+        },
+        "OP": "SET"
+    },
+{% endfor %}
 {% endif %}
     {
         "TUNNEL_DECAP_TABLE:IPINIP_TUNNEL" : {
@@ -110,6 +123,15 @@
         },
         "OP": "SET"
     },
+{% for prefix in ipv6_vlan_addresses|sort %}
+    {
+        "TUNNEL_DECAP_TERM_TABLE:IPINIP_SUBNET_V6:{{ prefix | network }}/{{ prefix | prefixlen }}" : {
+            "term_type":"MP2MP",
+            "subnet_type": "vlan"
+        },
+        "OP": "SET"
+    },
+{% endfor %}
 {% endif %}
     {
         "TUNNEL_DECAP_TABLE:IPINIP_V6_TUNNEL" : {

src/sonic-config-engine/tests/sample_output/py2/ipinip_subnet_decap_enable.json

@@ -8,6 +8,20 @@
         },
         "OP": "SET"
     },
+    {
+        "TUNNEL_DECAP_TERM_TABLE:IPINIP_SUBNET:192.168.0.0/27" : {
+            "term_type":"MP2MP",
+            "subnet_type": "vlan"
+        },
+        "OP": "SET"
+    },
+    {
+        "TUNNEL_DECAP_TERM_TABLE:IPINIP_SUBNET:192.168.200.0/27" : {
+            "term_type":"MP2MP",
+            "subnet_type": "vlan"
+        },
+        "OP": "SET"
+    },
     {
         "TUNNEL_DECAP_TABLE:IPINIP_TUNNEL" : {
             "tunnel_type":"IPINIP",

src/sonic-config-engine/tests/sample_output/py3/ipinip_subnet_decap_enable.json

@@ -8,6 +8,20 @@
         },
         "OP": "SET"
     },
+    {
+        "TUNNEL_DECAP_TERM_TABLE:IPINIP_SUBNET:192.168.0.0/27" : {
+            "term_type":"MP2MP",
+            "subnet_type": "vlan"
+        },
+        "OP": "SET"
+    },
+    {
+        "TUNNEL_DECAP_TERM_TABLE:IPINIP_SUBNET:192.168.200.0/27" : {
+            "term_type":"MP2MP",
+            "subnet_type": "vlan"
+        },
+        "OP": "SET"
+    },
     {
         "TUNNEL_DECAP_TABLE:IPINIP_TUNNEL" : {
             "tunnel_type":"IPINIP",