Add jwks support

Dockerfile

@@ -27,3 +27,5 @@ WORKDIR /go/src/github.com/coreos/jwtproxy/
 
 RUN go install -v github.com/coreos/jwtproxy/cmd/jwtproxy
 RUN rm -r /usr/local/go
+
+EXPOSE 8080

cmd/jwtproxy/main.go

@@ -29,6 +29,8 @@ import (
 	_ "github.com/coreos/jwtproxy/jwt/keyserver/keyregistry"
 	_ "github.com/coreos/jwtproxy/jwt/keyserver/keyregistry/keycache/memory"
 	_ "github.com/coreos/jwtproxy/jwt/keyserver/preshared"
+	_ "github.com/coreos/jwtproxy/jwt/keyserver/jwks"
+	_ "github.com/coreos/jwtproxy/jwt/keyserver/jwks/keycache/memory"
 	_ "github.com/coreos/jwtproxy/jwt/noncestorage/local"
 	_ "github.com/coreos/jwtproxy/jwt/privatekey/autogenerated"
 	_ "github.com/coreos/jwtproxy/jwt/privatekey/preshared"

jwt/keyserver/jwks/jwks.go

@@ -0,0 +1,184 @@
+// Copyright 2016 CoreOS, Inc
+//
+// 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 jwks
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+	"sync"
+	"time"
+
+	"github.com/coreos/go-oidc/jose"
+	"github.com/coreos/go-oidc/key"
+	"github.com/gregjones/httpcache"
+	"gopkg.in/yaml.v2"
+
+	"github.com/coreos/jwtproxy/config"
+	"github.com/coreos/jwtproxy/jwt/keyserver"
+	"github.com/coreos/jwtproxy/jwt/keyserver/jwks/keycache"
+)
+
+func init() {
+	keyserver.RegisterReader("jwks", constructReader)
+}
+
+type client struct {
+	cache        keycache.Cache
+	jwks         *url.URL
+	signerParams config.SignerParams
+	stopping     chan struct{}
+	inFlight     *sync.WaitGroup
+	httpClient   *http.Client
+}
+
+type Config struct {
+	Jwks config.URL `yaml:"jwks"`
+}
+
+type ReaderConfig struct {
+	Config `yaml:",inline"'`
+	Cache  *config.RegistrableComponentConfig `yaml:"cache"`
+}
+
+func (krc *client) GetPublicKey(issuer string, keyID string) (*key.PublicKey, error) {
+	// Query java web key set for a public key matching the given issuer and key ID.
+	pubkeyURL := krc.absURL(keyID)
+	pubkeyReq, err := krc.prepareRequest("GET", pubkeyURL, nil)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := krc.httpClient.Do(pubkeyReq)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		switch resp.StatusCode {
+		case http.StatusNotFound:
+			return nil, keyserver.ErrPublicKeyNotFound
+		case http.StatusForbidden:
+			return nil, keyserver.ErrPublicKeyExpired
+		default:
+			return nil, keyserver.ErrUnkownResponse
+		}
+	}
+
+	// Decode the public key we received as a JSON-encoded JWK.
+	var d struct {
+		Keys []jose.JWK `json:"keys"`
+	}
+	jsonDecoder := json.NewDecoder(resp.Body)
+	err = jsonDecoder.Decode(&d)
+	if err != nil {
+		return nil, err
+	}
+	if len(d.Keys) == 0 {
+		return nil, errors.New("zero keys in response")
+	}
+	ks := key.NewPublicKeySet(d.Keys, time.Now())
+
+	return ks.Key(keyID), nil
+}
+
+func (krc *client) Stop() <-chan struct{} {
+	finished := make(chan struct{})
+	// Stop the in flight requests
+	close(krc.stopping)
+	go func() {
+		krc.inFlight.Wait()
+
+		// Now stop the cache
+		if krc.cache != nil {
+			<-krc.cache.Stop()
+		}
+
+		close(finished)
+	}()
+	return finished
+}
+
+func (krc *client) prepareRequest(method string, url *url.URL, body io.Reader) (*http.Request, error) {
+	// Create an HTTP request to the key server to publish a new key.
+	req, err := http.NewRequest(method, url.String(), body)
+	if err != nil {
+		return nil, err
+	}
+
+	if method == "PUT" || method == "POST" {
+		req.Header.Add("Content-Type", "application/json")
+	}
+
+	// Add our user agent.
+	req.Header.Set("User-Agent", "JWTProxy/0.1.0")
+
+	return req, nil
+}
+
+func (krc *client) absURL(pathParams ...string) *url.URL {
+	escaped := make([]string, 0, len(pathParams)+1)
+	escaped = append(escaped, krc.jwks.Path)
+	for _, pathParam := range pathParams {
+		escaped = append(escaped, url.QueryEscape(pathParam))
+	}
+
+	absPath := path.Join(escaped...)
+	relurl, err := url.Parse(absPath)
+	if err != nil {
+		panic(err)
+	}
+	return krc.jwks.ResolveReference(relurl)
+}
+
+func constructReader(registrableComponentConfig config.RegistrableComponentConfig) (keyserver.Reader, error) {
+	bytes, err := yaml.Marshal(registrableComponentConfig.Options)
+	if err != nil {
+		return nil, err
+	}
+	var cfg ReaderConfig
+	err = yaml.Unmarshal(bytes, &cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	// Construct the public key cache.
+	cacheConfig := config.RegistrableComponentConfig{
+		Type: "memory",
+	}
+	if cfg.Cache != nil {
+		cacheConfig = *cfg.Cache
+	}
+
+	cache, err := keycache.NewCache(cacheConfig)
+	if err != nil {
+		return nil, fmt.Errorf("Unable to construct cache: %s", err)
+	}
+
+	httpClient := &http.Client{
+		Transport: httpcache.NewTransport(cache),
+	}
+
+	return &client{
+		jwks:       cfg.Jwks.URL,
+		inFlight:   &sync.WaitGroup{},
+		stopping:   make(chan struct{}),
+		cache:      cache,
+		httpClient: httpClient,
+	}, nil
+}

jwt/keyserver/jwks/keycache/keycache.go

@@ -0,0 +1,51 @@
+// Copyright 2016 CoreOS, Inc
+//
+// 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 keycache
+
+import (
+	"fmt"
+
+	"github.com/gregjones/httpcache"
+
+	"github.com/coreos/jwtproxy/config"
+	"github.com/coreos/jwtproxy/stop"
+)
+
+type Constructor func(config.RegistrableComponentConfig) (Cache, error)
+
+type Cache interface {
+	stop.Stoppable
+	httpcache.Cache
+}
+
+var keycaches = make(map[string]Constructor)
+
+func RegisterCache(name string, c Constructor) {
+	if c == nil {
+		panic("server: could not register nil ReaderConstructor")
+	}
+	if _, dup := keycaches[name]; dup {
+		panic("server: could not register duplicate ReaderConstructor: " + name)
+	}
+	keycaches[name] = c
+}
+
+func NewCache(cfg config.RegistrableComponentConfig) (Cache, error) {
+	c, ok := keycaches[cfg.Type]
+	if !ok {
+		return nil, fmt.Errorf("server: unknown Cache type %q (forgotten import?)", cfg.Type)
+	}
+	return c(cfg)
+}

jwt/keyserver/jwks/keycache/memory/memory.go

@@ -0,0 +1,44 @@
+// Copyright 2016 CoreOS, Inc
+//
+// 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 memory
+
+import (
+	log "github.com/Sirupsen/logrus"
+	"github.com/gregjones/httpcache"
+
+	"github.com/coreos/jwtproxy/config"
+	"github.com/coreos/jwtproxy/jwt/keyserver/jwks/keycache"
+	"github.com/coreos/jwtproxy/stop"
+)
+
+func init() {
+	keycache.RegisterCache("memory", constructor)
+}
+
+type cache struct {
+	*httpcache.MemoryCache
+}
+
+func constructor(registrableComponentConfig config.RegistrableComponentConfig) (keycache.Cache, error) {
+	log.Debug("Initializing in-memory key cache.")
+
+	return &cache{
+		MemoryCache: httpcache.NewMemoryCache(),
+	}, nil
+}
+
+func (c *cache) Stop() <-chan struct{} {
+	return stop.AlreadyDone
+}