[pipeline/trusted-resources]Add admission webhook

This commit is a followup work for Trust Task.(Forked from tektoncd/community#537)
Prior this commit we have added the verification of taskspec but didn’t include the webhook configuration and setup.
This commit includes the configuration and setup of the admission webhook and related docs.With this commit we can deploy a standalone webhookfor verification.

pipeline/trusted-resources/.gitignore

@@ -12,11 +12,6 @@ cosign.*
 payload.json
 signatures.json
 
-# tmp
-/config
-/cmd
-/examples
-
 # Precompiled Headers
 *.gch
 *.pch
@@ -63,7 +58,6 @@ cmd/*/kodata/source.tar.gz
 test/pullrequest/pullrequest-init
 /.bin/
 /bin/
-/etc
 
 # allow vendor
 !vendor/

pipeline/trusted-resources/README.md

@@ -2,7 +2,69 @@
 
 [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/tektoncd/experimental/blob/master/LICENSE)
 
-This is an experimental project to provide a seperate admission webhook for remote resources verification.
+This is an experimental project to provide a seperate webhook for remote resources verification.
+
+- [Install](#install)
+- [Uninstall](#uninstall)
+- [Development](#development)
+
+## Install
+
+Install and configure [`ko`](https://github.com/google/ko).
+
+Install tekton pipeline. To install from source, checkout to pipeline repo and execute:
+```bash
+ko apply -f config/
+```
+
+Generate cosign key pair
+```bash
+# cosign generate-key-pair k8s://tekton-pipelines/signing-secrets
+cosign generate-key-pair
+```
+
+Generate signed files
+```bash
+go run etc/signing.go
+```
+
+Then install the new admission webhook:
+```bash
+# delete secret if already exists
+# kubectl delete secret signing-secrets -n tekton-trusted-resources
+kubectl create secret generic signing-secrets \
+  --from-file=cosign.key=./cosign.key \
+  --from-literal=cosign.password='1234'\
+  --from-file=cosign.pub=./cosign.pub \
+  -n tekton-trusted-resources
+
+ko apply -f config/
+```
+
+Examples:
+```bash
+# Test API taskrun
+ko apply -f examples/1-test-taskrun-signed.yaml
+
+# Test OCI Bundle
+# add this secret to controller's service account
+kubectl create secret generic ${SECRET_NAME} \
+--from-file=.dockerconfigjson=<path/to/.docker/config.json> \
+--type=kubernetes.io/dockerconfigjson
+--namespace=tekton-pipelines
+
+tkn bundle push docker.io/my-dockerhub-username/testtask:latest -f examples/test_task.yaml
+cosign sign --key cosign.key docker.io/my-dockerhub-username/testtask:latest
+```
+
+## Uninstall
+
+```bash
+ko delete -f config/
+```
+
+
+## Development
 
 generate deepcopy code
 ```bash

pipeline/trusted-resources/cmd/webhook_trusted_resource/main.go

@@ -0,0 +1,113 @@
+/*
+Copyright 2022 The Tekton Authors
+
+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
+
+    http://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 main
+
+import (
+	"context"
+	"log"
+	"net/http"
+	"os"
+
+	taskvalidation "github.com/tektoncd/experimental/pipelines/trusted-resources/pkg/trustedtask"
+	"github.com/tektoncd/pipeline/pkg/apis/pipeline/v1beta1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"knative.dev/pkg/configmap"
+	"knative.dev/pkg/controller"
+	"knative.dev/pkg/injection"
+	"knative.dev/pkg/injection/sharedmain"
+	"knative.dev/pkg/signals"
+	"knative.dev/pkg/system"
+	"knative.dev/pkg/webhook"
+	"knative.dev/pkg/webhook/certificates"
+	"knative.dev/pkg/webhook/resourcesemantics"
+	"knative.dev/pkg/webhook/resourcesemantics/validation"
+)
+
+var types = map[schema.GroupVersionKind]resourcesemantics.GenericCRD{
+	// TODO: Add other types
+
+	// v1beta1
+	v1beta1.SchemeGroupVersion.WithKind("TaskRun"): &taskvalidation.TrustedTaskRun{},
+}
+
+func newValidationAdmissionController(ctx context.Context, cmw configmap.Watcher) *controller.Impl {
+	return validation.NewAdmissionController(ctx,
+
+		// Name of the resource webhook.
+		"validation.trustedresources.webhook.pipeline.tekton.dev",
+
+		// The path on which to serve the webhook.
+		"/resource-validation",
+
+		// The resources to validate and default.
+		types,
+
+		// A function that infuses the context passed to Validate/SetDefaults with custom metadata.
+		nil,
+
+		// Whether to disallow unknown fields.
+		true,
+	)
+}
+
+func main() {
+	serviceName := os.Getenv("WEBHOOK_SERVICE_NAME")
+	if serviceName == "" {
+		serviceName = "tekton-trusted-resources-webhook"
+	}
+
+	secretName := os.Getenv("WEBHOOK_SECRET_NAME")
+	if secretName == "" {
+		secretName = "trusted-resources-webhook-certs" // #nosec
+	}
+
+	// Scope informers to the webhook's namespace instead of cluster-wide
+	ctx := injection.WithNamespaceScope(signals.NewContext(), system.Namespace())
+
+	// Set up a signal context with our webhook options
+	ctx = webhook.WithOptions(ctx, webhook.Options{
+		ServiceName: serviceName,
+		Port:        8443,
+		SecretName:  secretName,
+	})
+
+	mux := http.NewServeMux()
+
+	mux.HandleFunc("/", handler)
+	mux.HandleFunc("/health", handler)
+	mux.HandleFunc("/readiness", handler)
+
+	port := os.Getenv("PROBES_PORT")
+	if port == "" {
+		port = "8080"
+	}
+
+	go func() {
+		// start the web server on port and accept requests
+		log.Printf("Readiness and health check server listening on port %s", port)
+		log.Fatal(http.ListenAndServe(":"+port, mux))
+	}()
+
+	sharedmain.MainWithContext(ctx, serviceName,
+		certificates.NewController,
+		newValidationAdmissionController,
+	)
+}
+
+func handler(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(http.StatusOK)
+}

pipeline/trusted-resources/config/100-namespace.yaml

@@ -0,0 +1,21 @@
+# Copyright 2019 The Tekton Authors
+#
+# 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
+#
+#     http://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: v1
+kind: Namespace
+metadata:
+  name: tekton-trusted-resources
+  labels:
+    app.kubernetes.io/instance: default
+    app.kubernetes.io/part-of: admissioncontrol

pipeline/trusted-resources/config/200-clusterrole.yaml

@@ -0,0 +1,43 @@
+# Copyright 2022 The Tekton Authors
+#
+# 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.
+
+kind: ClusterRole
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: tekton-trusted-resources-webhook-cluster-access
+  labels:
+    app.kubernetes.io/component: tekton-trusted-resources
+    app.kubernetes.io/instance: default
+    app.kubernetes.io/part-of: admissioncontrol
+rules:
+  - apiGroups: ["admissionregistration.k8s.io"]
+    # The webhook performs a reconciliation on these two resources and continuously
+    # updates configuration.
+    resources: ["mutatingwebhookconfigurations", "validatingwebhookconfigurations"]
+    # knative starts informers on these things, which is why we need get, list and watch.
+    verbs: ["list", "watch"]
+  - apiGroups: ["admissionregistration.k8s.io"]
+    resources: ["validatingwebhookconfigurations"]
+    resourceNames: ["validation.trustedresources.webhook.pipeline.tekton.dev"]
+    # When there are changes to the configs or secrets, knative updates the validatingwebhook config
+    # with the updated certificates or the refreshed set of rules.
+    verbs: ["get", "update"]
+  - apiGroups: ["admissionregistration.k8s.io"]
+    resources: ["mutatingwebhookconfigurations"]
+    # This mutating webhook is responsible for applying defaults to tekton objects
+    # as they are received.
+    resourceNames: ["trustedresources.webhook.pipeline.tekton.dev"]
+    # When there are changes to the configs or secrets, knative updates the mutatingwebhook config
+    # with the updated certificates or the refreshed set of rules.
+    verbs: ["get", "update", "delete"]

pipeline/trusted-resources/config/200-role.yaml

@@ -0,0 +1,68 @@
+# Copyright 2022 The Tekton Authors
+#
+# 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.
+
+kind: Role
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: tekton-trusted-resources-webhook
+  namespace: tekton-trusted-resources
+  labels:
+    app.kubernetes.io/component: tekton-trusted-resources
+    app.kubernetes.io/instance: default
+    app.kubernetes.io/part-of: admissioncontrol
+rules:
+  # Webhook needs to list and watch configmaps for reconciliation.
+  - apiGroups: [""]
+    resources: ["configmaps"]
+    verbs: ["list", "watch"]
+  # The webhook needs access to these configmaps for logging information.
+  - apiGroups: [""]
+    resources: ["configmaps"]
+    verbs: ["get"]
+    resourceNames: ["config-logging", "config-observability", "config-leader-election", "config-trusted-resources"]
+  # The webhook daemon makes a reconciliation loop on webhook-certs. Whenever
+  # the secret changes it updates the webhook configurations with the certificates
+  # stored in the secret.
+  - apiGroups: [""]
+    resources: ["secrets"]
+    verbs: ["list", "watch"]
+  # The webhook needs access to these secrets for certs and verificaiton
+  - apiGroups: [""]
+    resources: ["secrets"]
+    verbs: ["get", "update"]
+    resourceNames: ["trusted-resources-webhook-certs", "signing-secret"]
+  # The webhook needs access to it's SA to make fetch resources
+  - apiGroups: [""]
+    resources: ["serviceaccounts"]
+    verbs: ["get"]
+    resourceNames: ["tekton-trusted-resources-webhook"]
+  # The webhook needs access to it's ns to fetch resources in this ns
+  - apiGroups: [""]
+    resources: ["namespaces"]
+    verbs: ["get"]
+    resourceNames: ["tekton-trusted-resources"]
+---
+kind: Role
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: tekton-trusted-resources-leader-election
+  namespace: tekton-trusted-resources
+  labels:
+    app.kubernetes.io/instance: default
+    app.kubernetes.io/part-of: admissioncontrol
+rules:
+  # We uses leases for leaderelection
+  - apiGroups: ["coordination.k8s.io"]
+    resources: ["leases"]
+    verbs: ["get", "list", "create", "update", "delete", "patch", "watch"]

pipeline/trusted-resources/config/200-serviceaccount.yaml

@@ -0,0 +1,25 @@
+# Copyright 2022 The Tekton Authors
+#
+# 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
+#
+#     http://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: v1
+kind: ServiceAccount
+metadata:
+  name: tekton-trusted-resources-webhook
+  namespace: tekton-trusted-resources
+  labels:
+    app.kubernetes.io/component: tekton-trusted-resources
+    app.kubernetes.io/instance: default
+    app.kubernetes.io/part-of: admissioncontrol
+# Uncomment this and create imagePullSecrets according to README to pull OCI bundle from registry
+#imagePullSecrets:
+#- name: myregistrykey

pipeline/trusted-resources/config/201-clusterrolebinding.yaml

@@ -0,0 +1,30 @@
+# Copyright 2022 The Tekton Authors
+#
+# 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
+#
+#     http://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: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: tekton-trusted-resources-webhook-cluster-access
+  labels:
+    app.kubernetes.io/component: tekton-trusted-resources
+    app.kubernetes.io/instance: default
+    app.kubernetes.io/part-of: admissioncontrol
+subjects:
+  - kind: ServiceAccount
+    name: tekton-trusted-resources-webhook
+    namespace: tekton-trusted-resources
+roleRef:
+  kind: ClusterRole
+  name: tekton-trusted-resources-webhook-cluster-access
+  apiGroup: rbac.authorization.k8s.io