allNodesSecurityGroupRules: relax remote fields

Don't make `remoteManagedGroups` required, since a user can use
`remoteIPPrefix` instead or even no remote parameter at all.
It's fine because Neutron will set it to an fully-open CIDR if no
remote field is provided.

docs/book/src/clusteropenstack/configuration.md

@@ -565,6 +565,7 @@ permitted from anywhere, as with the default rules).
 We can add security group rules that authorize traffic from all nodes via `allNodesSecurityGroupRules`.
 It takes a list of security groups rules that should be applied to selected nodes.
 The following rule fields are mutually exclusive: `remoteManagedGroups`, `remoteGroupID` and `remoteIPPrefix`.
+If none of these fields are set, the rule will have a remote IP prefix of `0.0.0.0/0` per Neutron default.
 
 Valid values for `remoteManagedGroups` are `controlplane`, `worker` and `bastion`.
 

docs/book/src/topics/crd-changes/v1alpha7-to-v1beta1.md

@@ -394,6 +394,9 @@ The field `managedSecurityGroups` is now a pointer to a `ManagedSecurityGroups`
 Also, we can now add security group rules that authorize traffic from all nodes via `allNodesSecurityGroupRules`.
 It takes a list of security groups rules that should be applied to selected nodes.
 The following rule fields are mutually exclusive: `remoteManagedGroups`, `remoteGroupID` and `remoteIPPrefix`.
+If none of these fields are set, the rule will have a remote IP prefix of `0.0.0.0/0` per Neutron default.
+
+```yaml
 Valid values for `remoteManagedGroups` are `controlplane`, `worker` and `bastion`.
 
 Also, `OpenStackCluster.Spec.AllowAllInClusterTraffic` moved under `ManagedSecurityGroups`.

pkg/cloud/services/networking/securitygroups.go

@@ -297,10 +297,6 @@ func getAllNodesRules(remoteManagedGroups map[string]string, allNodesSecurityGro
 
 // validateRemoteManagedGroups validates that the remoteManagedGroups target existing managed security groups.
 func validateRemoteManagedGroups(remoteManagedGroups map[string]string, ruleRemoteManagedGroups []infrav1.ManagedSecurityGroupName) error {
-	if len(ruleRemoteManagedGroups) == 0 {
-		return fmt.Errorf("remoteManagedGroups is required")
-	}
-
 	for _, group := range ruleRemoteManagedGroups {
 		if _, ok := remoteManagedGroups[group.String()]; !ok {
 			return fmt.Errorf("remoteManagedGroups: %s is not a valid remote managed security group", group)

pkg/cloud/services/networking/securitygroups_test.go

@@ -49,19 +49,14 @@ func TestValidateRemoteManagedGroups(t *testing.T) {
 			wantErr: true,
 		},
 		{
-			name: "Valid rule with missing remoteManagedGroups",
+			name: "Valid rule with no remoteManagedGroups",
 			rule: infrav1.SecurityGroupRuleSpec{
-				PortRangeMin: ptr.To(22),
-				PortRangeMax: ptr.To(22),
-				Protocol:     ptr.To("tcp"),
+				PortRangeMin:   ptr.To(22),
+				PortRangeMax:   ptr.To(22),
+				Protocol:       ptr.To("tcp"),
+				RemoteIPPrefix: ptr.To("0.0.0.0/0"),
 			},
-			remoteManagedGroups: map[string]string{
-				"self":         "self",
-				"controlplane": "1",
-				"worker":       "2",
-				"bastion":      "3",
-			},
-			wantErr: true,
+			wantErr: false,
 		},
 		{
 			name: "Valid rule with remoteManagedGroups",
@@ -171,6 +166,70 @@ func TestGetAllNodesRules(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "Valid remoteIPPrefix in a rule",
+			remoteManagedGroups: map[string]string{
+				"controlplane": "1",
+				"worker":       "2",
+			},
+			allNodesSecurityGroupRules: []infrav1.SecurityGroupRuleSpec{
+				{
+					Protocol:       ptr.To("tcp"),
+					PortRangeMin:   ptr.To(22),
+					PortRangeMax:   ptr.To(22),
+					RemoteIPPrefix: ptr.To("0.0.0.0/0"),
+				},
+			},
+			wantRules: []resolvedSecurityGroupRuleSpec{
+				{
+					Protocol:       "tcp",
+					PortRangeMin:   22,
+					PortRangeMax:   22,
+					RemoteIPPrefix: "0.0.0.0/0",
+				},
+			},
+		},
+		{
+			name: "Valid allNodesSecurityGroupRules with no remote parameter",
+			remoteManagedGroups: map[string]string{
+				"controlplane": "1",
+				"worker":       "2",
+			},
+			allNodesSecurityGroupRules: []infrav1.SecurityGroupRuleSpec{
+				{
+					Protocol:     ptr.To("tcp"),
+					PortRangeMin: ptr.To(22),
+					PortRangeMax: ptr.To(22),
+				},
+			},
+			wantRules: []resolvedSecurityGroupRuleSpec{
+				{
+					Protocol:     "tcp",
+					PortRangeMin: 22,
+					PortRangeMax: 22,
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "Invalid allNodesSecurityGroupRules with bastion while remoteManagedGroups does not have bastion",
+			remoteManagedGroups: map[string]string{
+				"controlplane": "1",
+				"worker":       "2",
+			},
+			allNodesSecurityGroupRules: []infrav1.SecurityGroupRuleSpec{
+				{
+					Protocol:     ptr.To("tcp"),
+					PortRangeMin: ptr.To(22),
+					PortRangeMax: ptr.To(22),
+					RemoteManagedGroups: []infrav1.ManagedSecurityGroupName{
+						"bastion",
+					},
+				},
+			},
+			wantRules: nil,
+			wantErr:   true,
+		},
 		{
 			name: "Invalid allNodesSecurityGroupRules with wrong remoteManagedGroups",
 			remoteManagedGroups: map[string]string{