Allow including both podSelector and namespaceSelector in a NetworkPolicyPeer

pkg/apis/networking/types.go

@@ -159,22 +159,28 @@ type IPBlock struct {
 	Except []string
 }
 
-// NetworkPolicyPeer describes a peer to allow traffic from. Exactly one of its fields
-// must be specified.
+// NetworkPolicyPeer describes a peer to allow traffic from.
 type NetworkPolicyPeer struct {
-	// This is a label selector which selects Pods in this namespace. This field
-	// follows standard label selector semantics. If present but empty, this selector
-	// selects all pods in this namespace.
+	// This is a label selector which selects Pods. This field follows standard label
+	// selector semantics; if present but empty, it selects all pods.
+	//
+	// If NamespaceSelector is also set, then the NetworkPolicyPeer as a whole selects
+	// the Pods matching PodSelector in the Namespaces selected by NamespaceSelector.
+	// Otherwise it selects the Pods matching PodSelector in the policy's own Namespace.
 	// +optional
 	PodSelector *metav1.LabelSelector
 
-	// Selects Namespaces using cluster scoped-labels. This matches all pods in all
-	// namespaces selected by this label selector. This field follows standard label
-	// selector semantics. If present but empty, this selector selects all namespaces.
+	// Selects Namespaces using cluster-scoped labels. This field follows standard label
+	// selector semantics; if present but empty, it selects all namespaces.
+	//
+	// If PodSelector is also set, then the NetworkPolicyPeer as a whole selects
+	// the Pods matching PodSelector in the Namespaces selected by NamespaceSelector.
+	// Otherwise it selects all Pods in the Namespaces selected by NamespaceSelector.
 	// +optional
 	NamespaceSelector *metav1.LabelSelector
 
-	// IPBlock defines policy on a particular IPBlock
+	// IPBlock defines policy on a particular IPBlock. If this field is set then
+	// neither of the other fields can be.
 	// +optional
 	IPBlock *IPBlock
 }

pkg/apis/networking/validation/validation.go

@@ -75,8 +75,8 @@ func ValidateNetworkPolicyPeer(peer *networking.NetworkPolicyPeer, peerPath *fie
 
 	if numPeers == 0 {
 		allErrs = append(allErrs, field.Required(peerPath, "must specify a peer"))
-	} else if numPeers > 1 {
-		allErrs = append(allErrs, field.Forbidden(peerPath, "may not specify more than 1 peer"))
+	} else if numPeers > 1 && peer.IPBlock != nil {
+		allErrs = append(allErrs, field.Forbidden(peerPath, "may not specify both ipBlock and another peer"))
 	}
 
 	return allErrs

pkg/apis/networking/validation/validation_test.go

@@ -128,6 +128,28 @@ func TestValidateNetworkPolicy(t *testing.T) {
 				PodSelector: metav1.LabelSelector{
 					MatchLabels: map[string]string{"a": "b"},
 				},
+				Ingress: []networking.NetworkPolicyIngressRule{
+					{
+						From: []networking.NetworkPolicyPeer{
+							{
+								NamespaceSelector: &metav1.LabelSelector{
+									MatchLabels: map[string]string{"c": "d"},
+								},
+								PodSelector: &metav1.LabelSelector{
+									MatchLabels: map[string]string{"e": "f"},
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+		{
+			ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "bar"},
+			Spec: networking.NetworkPolicySpec{
+				PodSelector: metav1.LabelSelector{
+					MatchLabels: map[string]string{"a": "b"},
+				},
 				Egress: []networking.NetworkPolicyEgressRule{
 					{
 						To: []networking.NetworkPolicyPeer{
@@ -256,7 +278,7 @@ func TestValidateNetworkPolicy(t *testing.T) {
 
 	invalidSelector := map[string]string{"NoUppercaseOrSpecialCharsLike=Equals": "b"}
 	errorCases := map[string]networking.NetworkPolicy{
-		"namespaceSelector and podSelector": {
+		"namespaceSelector and ipBlock": {
 			ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "bar"},
 			Spec: networking.NetworkPolicySpec{
 				PodSelector: metav1.LabelSelector{
@@ -266,16 +288,25 @@ func TestValidateNetworkPolicy(t *testing.T) {
 					{
 						From: []networking.NetworkPolicyPeer{
 							{
-								PodSelector: &metav1.LabelSelector{
-									MatchLabels: map[string]string{"c": "d"},
-								},
 								NamespaceSelector: &metav1.LabelSelector{
 									MatchLabels: map[string]string{"c": "d"},
 								},
+								IPBlock: &networking.IPBlock{
+									CIDR:   "192.168.0.0/16",
+									Except: []string{"192.168.3.0/24", "192.168.4.0/24"},
+								},
 							},
 						},
 					},
 				},
+			},
+		},
+		"podSelector and ipBlock": {
+			ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "bar"},
+			Spec: networking.NetworkPolicySpec{
+				PodSelector: metav1.LabelSelector{
+					MatchLabels: map[string]string{"a": "b"},
+				},
 				Egress: []networking.NetworkPolicyEgressRule{
 					{
 						To: []networking.NetworkPolicyPeer{
@@ -283,8 +314,9 @@ func TestValidateNetworkPolicy(t *testing.T) {
 								PodSelector: &metav1.LabelSelector{
 									MatchLabels: map[string]string{"c": "d"},
 								},
-								NamespaceSelector: &metav1.LabelSelector{
-									MatchLabels: map[string]string{"c": "d"},
+								IPBlock: &networking.IPBlock{
+									CIDR:   "192.168.0.0/16",
+									Except: []string{"192.168.3.0/24", "192.168.4.0/24"},
 								},
 							},
 						},

staging/src/k8s.io/api/extensions/v1beta1/types.go

@@ -1256,22 +1256,26 @@ type IPBlock struct {
 
 // DEPRECATED 1.9 - This group version of NetworkPolicyPeer is deprecated by networking/v1/NetworkPolicyPeer.
 type NetworkPolicyPeer struct {
-	// Exactly one of the following must be specified.
-
-	// This is a label selector which selects Pods in this namespace.
-	// This field follows standard label selector semantics.
-	// If present but empty, this selector selects all pods in this namespace.
+	// This is a label selector which selects Pods. This field follows standard label
+	// selector semantics; if present but empty, it selects all pods.
+	//
+	// If NamespaceSelector is also set, then the NetworkPolicyPeer as a whole selects
+	// the Pods matching PodSelector in the Namespaces selected by NamespaceSelector.
+	// Otherwise it selects the Pods matching PodSelector in the policy's own Namespace.
 	// +optional
 	PodSelector *metav1.LabelSelector `json:"podSelector,omitempty" protobuf:"bytes,1,opt,name=podSelector"`
 
-	// Selects Namespaces using cluster scoped-labels.  This
-	// matches all pods in all namespaces selected by this label selector.
-	// This field follows standard label selector semantics.
-	// If present but empty, this selector selects all namespaces.
+	// Selects Namespaces using cluster-scoped labels. This field follows standard label
+	// selector semantics; if present but empty, it selects all namespaces.
+	//
+	// If PodSelector is also set, then the NetworkPolicyPeer as a whole selects
+	// the Pods matching PodSelector in the Namespaces selected by NamespaceSelector.
+	// Otherwise it selects all Pods in the Namespaces selected by NamespaceSelector.
 	// +optional
 	NamespaceSelector *metav1.LabelSelector `json:"namespaceSelector,omitempty" protobuf:"bytes,2,opt,name=namespaceSelector"`
 
-	// IPBlock defines policy on a particular IPBlock
+	// IPBlock defines policy on a particular IPBlock. If this field is set then
+	// neither of the other fields can be.
 	// +optional
 	IPBlock *IPBlock `json:"ipBlock,omitempty" protobuf:"bytes,3,rep,name=ipBlock"`
 }

staging/src/k8s.io/api/networking/v1/types.go

@@ -161,22 +161,29 @@ type IPBlock struct {
 	Except []string `json:"except,omitempty" protobuf:"bytes,2,rep,name=except"`
 }
 
-// NetworkPolicyPeer describes a peer to allow traffic from. Exactly one of its fields
-// must be specified.
+// NetworkPolicyPeer describes a peer to allow traffic from. Only certain combinations of
+// fields are allowed
 type NetworkPolicyPeer struct {
-	// This is a label selector which selects Pods in this namespace. This field
-	// follows standard label selector semantics. If present but empty, this selector
-	// selects all pods in this namespace.
+	// This is a label selector which selects Pods. This field follows standard label
+	// selector semantics; if present but empty, it selects all pods.
+	//
+	// If NamespaceSelector is also set, then the NetworkPolicyPeer as a whole selects
+	// the Pods matching PodSelector in the Namespaces selected by NamespaceSelector.
+	// Otherwise it selects the Pods matching PodSelector in the policy's own Namespace.
 	// +optional
 	PodSelector *metav1.LabelSelector `json:"podSelector,omitempty" protobuf:"bytes,1,opt,name=podSelector"`
 
-	// Selects Namespaces using cluster scoped-labels. This matches all pods in all
-	// namespaces selected by this label selector. This field follows standard label
-	// selector semantics. If present but empty, this selector selects all namespaces.
+	// Selects Namespaces using cluster-scoped labels. This field follows standard label
+	// selector semantics; if present but empty, it selects all namespaces.
+	//
+	// If PodSelector is also set, then the NetworkPolicyPeer as a whole selects
+	// the Pods matching PodSelector in the Namespaces selected by NamespaceSelector.
+	// Otherwise it selects all Pods in the Namespaces selected by NamespaceSelector.
 	// +optional
 	NamespaceSelector *metav1.LabelSelector `json:"namespaceSelector,omitempty" protobuf:"bytes,2,opt,name=namespaceSelector"`
 
-	// IPBlock defines policy on a particular IPBlock
+	// IPBlock defines policy on a particular IPBlock. If this field is set then
+	// neither of the other fields can be.
 	// +optional
 	IPBlock *IPBlock `json:"ipBlock,omitempty" protobuf:"bytes,3,rep,name=ipBlock"`
 }