From 8cd443b8fe06005b49dc3d21021fae6b52eb6106 Mon Sep 17 00:00:00 2001
From: Prince Pereira <ppereira@microsoft.com>
Date: Mon, 9 Sep 2024 12:03:16 +0530
Subject: [PATCH] Sample changes for dualstack testing.

---
 cni/cni.go                                   | 25 +++++++
 example/cni_dualstack_sample.conf            | 78 ++++++++++++++++++++
 scripts/autogencniconf/generateCNIConfig.ps1 | 14 +++-
 3 files changed, 116 insertions(+), 1 deletion(-)
 create mode 100644 example/cni_dualstack_sample.conf

diff --git a/cni/cni.go b/cni/cni.go
index 4a58dcc1..c4df4d61 100644
--- a/cni/cni.go
+++ b/cni/cni.go
@@ -70,6 +70,7 @@ type NetworkConfig struct {
 	Name             string           `json:"name"` // Name is the Network Name. We would also use this as the Type of HNS Network
 	Type             string           `json:"type"` // As per SPEC, Type is Name of the Binary
 	Ipam             IpamConfig       `json:"ipam"`
+	Ipamv6           IpamConfig       `json:"ipamv6"`
 	DNS              cniTypes.DNS     `json:"dns"`
 	OptionalFlags    OptionalFlags    `json:"optionalFlags"`
 	RuntimeConfig    RuntimeConfig    `json:"runtimeConfig"`
@@ -225,6 +226,30 @@ func (config *NetworkConfig) GetNetworkInfo(podNamespace string) (ninfo *network
 		subnets = append(subnets, subnet)
 	}
 
+	if config.OptionalFlags.EnableDualStack && config.Ipamv6.Subnet != "" {
+		ip, s, _ := net.ParseCIDR(config.Ipamv6.Subnet)
+		if ip.To4() == nil && len(ip) == net.IPv6len {
+			gatewayIP := make(net.IP, len(ip))
+			copy(gatewayIP, ip)
+			// Find the first IP in the subnet (usually the gateway)
+			for i := len(gatewayIP) - 1; i >= 0; i-- {
+				gatewayIP[i]++
+				if gatewayIP[i] != 0 {
+					break
+				}
+			}
+			if config.Ipamv6.Routes != nil && len(config.Ipamv6.Routes) > 0 && config.Ipamv6.Routes[0].GW != nil {
+				gatewayIP = config.Ipamv6.Routes[0].GW
+			}
+			subnet := network.SubnetInfo{
+				AddressPrefix:  *s,
+				GatewayAddress: gatewayIP,
+				Policies:       []network.Policy{},
+			}
+			subnets = append(subnets, subnet)
+		}
+	}
+
 	if len(config.DNS.Search) > 0 {
 		if podNamespace != "" {
 			config.DNS.Search[0] = podNamespace + "." + config.DNS.Search[0]
diff --git a/example/cni_dualstack_sample.conf b/example/cni_dualstack_sample.conf
new file mode 100644
index 00000000..1f49a60e
--- /dev/null
+++ b/example/cni_dualstack_sample.conf
@@ -0,0 +1,78 @@
+{
+    "cniVersion": "0.2.0",
+    "name": "ContainerHostA",
+    "type": "sdnbridge",
+    "master": "Ethernet",
+    "capabilities": {
+        "portMappings": true,
+        "dns" : true
+    },
+    "ipam": {
+        "environment": "azure",
+        "subnet": "192.168.100.0/24",
+        "routes": [
+            {
+                "GW": "192.168.100.2"
+            }
+        ]
+    },
+    "ipamv6": {
+        "environment": "azure",
+        "subnet": "10::06/64",
+        "routes": [
+            {
+                "GW": "10::02"
+            }
+        ]
+    },
+    "dns": {
+        "Nameservers": [
+            "168.63.129.16"
+        ],
+        "Search": [
+            "svc.cluster.local"
+        ]
+    },
+    "optionalFlags" : {
+        "localRoutedPortMapping" : true,
+        "allowAclPortMapping" : true,
+        "enableDualStack" : true
+    },
+    "AdditionalArgs": [
+        {
+            "Name": "EndpointPolicy",
+            "Value": {
+                "Type": "OutBoundNAT",
+                "Settings": {
+                    "Exceptions": [
+                        "192.168.100.0/24",
+                        "192.168.100.2/32"
+                    ]
+                }
+            }
+        }
+        ,{
+            "Name": "EndpointPolicy",
+            "Value": {
+                "Type":"ACL",
+                "Settings": {
+                    "Action": "Allow",
+                    "Direction": "Out",
+                    "Priority": 2000
+                }
+            }
+        }
+        ,{
+            "Name": "EndpointPolicy",
+            "Value": {
+                "Type":"ACL",
+                "Settings": {
+                    "Action": "Allow",
+                    "Direction": "In",
+                    "Priority": 2000
+                }
+            }
+        }
+
+    ]
+}
diff --git a/scripts/autogencniconf/generateCNIConfig.ps1 b/scripts/autogencniconf/generateCNIConfig.ps1
index e31becae..fa3b4ced 100644
--- a/scripts/autogencniconf/generateCNIConfig.ps1
+++ b/scripts/autogencniconf/generateCNIConfig.ps1
@@ -70,6 +70,7 @@ enum WKOptionalKeysFlag {
     Ipam = 2 #[WKOptionalKeysFlag]::NoWKOptKeys -shl 1
     Dns = 4 #[WKOptionalKeysFlag]::NoWKOptKeys -shl 2
     MaxFlags = 8 #[WKOptionalKeysFlag]::NoWKOptKeys -shl 3
+    Ipamv6 = 16 #[WKOptionalKeysFlag]::NoWKOptKeys -shl 4
 }
 
 class Policy {
@@ -181,7 +182,7 @@ class CniConf {
         # Set optional fields to be populated
         $this.OptKeyParams = $this.OptKeyParams -bor [OptionalKeysFlag]::Capabilities -bor [OptionalKeysFlag]::Master
         # Set wellknown optional fields to be populated
-        $this.WKOptKeyParams = $this.WKOptKeyParams -bor [WKOptionalKeysFlag]::Dns -bor [WKOptionalKeysFlag]::Ipam
+        $this.WKOptKeyParams = $this.WKOptKeyParams -bor [WKOptionalKeysFlag]::Dns -bor [WKOptionalKeysFlag]::Ipam -bor [WKOptionalKeysFlag]::Ipamv6
     }
 
     EnsureMandatoryParametersPresent([System.Object] $cniArgs) {
@@ -245,6 +246,17 @@ class CniConf {
                     $this.CniBase.Add('ipam', $ipamFields)
                 }
 
+                ([WKOptionalKeysFlag]::Ipamv6).value__ {
+                    $ipamFields = [System.Collections.Specialized.OrderedDictionary]::new()
+                    $ipamFields.Add('environment', 'azure')
+                    $ipamFields.Add('subnet', $this.Args.Subnet)
+                    $routes = @()
+                    $routes += (@{'GW'=$this.Args.Gateway;})
+                    $ipamFields.Add('routes', $routes)
+
+                    $this.CniBase.Add('ipamv6', $ipamFields)
+                }
+
                 ([WKOptionalKeysFlag]::Dns).value__ {
                     $dnsFields = [System.Collections.Specialized.OrderedDictionary]::new()
                     $nameservers = @()