# Copyright 2021 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
apiVersion: templates.gatekeeper.sh/v1alpha1
kind: ConstraintTemplate
metadata:
  name: gcp-dnssec-prevent-rsasha1-v1
spec:
  crd:
    spec:
      names:
        kind: GCPDNSSECPreventRSASHA1ConstraintV1
      validation:
        openAPIV3Schema:
          properties:
            keyType:
              description: This can be ZONE_SIGNING, KEY_SIGNING, or omitted to match
                any type.
              type: string
  targets:
    validation.gcp.forsetisecurity.org:
      rego: |
        #
        # Copyright 2021 Google LLC
        #
        # Licensed under the Apache License, Version 2.0 (the "License");
        # you may not use this file except in compliance with the License.
        # You may obtain a copy of the License at
        #
        #     https://www.apache.org/licenses/LICENSE-2.0
        #
        # Unless required by applicable law or agreed to in writing, software
        # distributed under the License is distributed on an "AS IS" BASIS,
        # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
        # See the License for the specific language governing permissions and
        # limitations under the License.
        #

        package templates.gcp.GCPDNSSECPreventRSASHA1ConstraintV1

        import data.validator.gcp.lib as lib

        deny[{
        	"msg": message,
        	"details": metadata,
        }] {
        	constraint := input.constraint
        	lib.get_constraint_params(constraint, params)

        	asset := input.asset
        	asset.asset_type == "dns.googleapis.com/ManagedZone"

        	dnssecConfig := asset.resource.data.dnssecConfig

        	keySpec := dnssecConfig.defaultKeySpecs[_]

        	keySpec.algorithm == "RSASHA1"

        	check_key_type(params, keySpec)

        	message := sprintf("%v: DNSSEC has weak RSASHA1 algorithm enabled", [asset.name])
        	metadata := {"resource": asset.name}
        }

        check_key_type(params, keySpec) {
        	lib.has_field(params, "keyType")
        	keySpec.keyType == params.keyType
        }

        check_key_type(params, keySpec) {
        	not lib.has_field(params, "keyType")
        }
        #ENDINLINE
