Merge pull request #14 from caos/feat/end-session

feat: terminate session (front channel logout)

example/internal/mock/storage.go

@@ -143,6 +143,9 @@ func (s *AuthStorage) AuthRequestByID(_ context.Context, id string) (op.AuthRequ
 func (s *AuthStorage) CreateToken(_ context.Context, authReq op.AuthRequest) (string, time.Time, error) {
 	return authReq.GetID(), time.Now().UTC().Add(5 * time.Minute), nil
 }
+func (s *AuthStorage) TerminateSession(_ context.Context, userID, clientID string) error {
+	return nil
+}
 func (s *AuthStorage) GetSigningKey(_ context.Context, keyCh chan<- jose.SigningKey, _ chan<- error, _ <-chan time.Time) {
 	keyCh <- jose.SigningKey{Algorithm: jose.RS256, Key: s.key}
 }
@@ -233,6 +236,9 @@ func (c *ConfClient) RedirectURIs() []string {
 		"https://op.certification.openid.net:62064/authz_post",
 	}
 }
+func (c *ConfClient) PostLogoutRedirectURIs() []string {
+	return []string{}
+}
 
 func (c *ConfClient) LoginURL(id string) string {
 	return "login?id=" + id

pkg/oidc/session.go

@@ -0,0 +1,7 @@
+package oidc
+
+type EndSessionRequest struct {
+	IdTokenHint           string `schema:"id_token_hint"`
+	PostLogoutRedirectURI string `schema:"post_logout_redirect_uri"`
+	State                 string `schema:"state"`
+}

pkg/op/client.go

@@ -14,6 +14,7 @@ const (
 type Client interface {
 	GetID() string
 	RedirectURIs() []string
+	PostLogoutRedirectURIs() []string
 	ApplicationType() ApplicationType
 	GetAuthMethod() AuthMethod
 	LoginURL(string) string

pkg/op/config.go

@@ -12,6 +12,7 @@ type Configuration interface {
 	AuthorizationEndpoint() Endpoint
 	TokenEndpoint() Endpoint
 	UserinfoEndpoint() Endpoint
+	EndSessionEndpoint() Endpoint
 	KeysEndpoint() Endpoint
 
 	AuthMethodPostSupported() bool

pkg/op/default_op.go

@@ -2,6 +2,7 @@ package op
 
 import (
 	"context"
+	"errors"
 	"net/http"
 	"time"
 
@@ -10,13 +11,15 @@ import (
 
 	"github.com/caos/logging"
 	"github.com/caos/oidc/pkg/oidc"
+	"github.com/caos/oidc/pkg/rp"
 )
 
 const (
 	defaultAuthorizationEndpoint = "authorize"
 	defaulTokenEndpoint          = "oauth/token"
 	defaultIntrospectEndpoint    = "introspect"
 	defaultUserinfoEndpoint      = "userinfo"
+	defaultEndSessionEndpoint    = "end_session"
 	defaultKeysEndpoint          = "keys"
 
 	AuthMethodBasic AuthMethod = "client_secret_basic"
@@ -30,6 +33,7 @@ var (
 		Token:                 NewEndpoint(defaulTokenEndpoint),
 		IntrospectionEndpoint: NewEndpoint(defaultIntrospectEndpoint),
 		Userinfo:              NewEndpoint(defaultUserinfoEndpoint),
+		EndSessionEndpoint:    NewEndpoint(defaultEndSessionEndpoint),
 		JwksURI:               NewEndpoint(defaultKeysEndpoint),
 	}
 )
@@ -39,6 +43,7 @@ type DefaultOP struct {
 	endpoints   *endpoints
 	storage     Storage
 	signer      Signer
+	verifier    rp.Verifier
 	crypto      Crypto
 	http        *http.Server
 	decoder     *schema.Decoder
@@ -49,8 +54,9 @@ type DefaultOP struct {
 }
 
 type Config struct {
-	Issuer    string
-	CryptoKey [32]byte
+	Issuer                   string
+	CryptoKey                [32]byte
+	DefaultLogoutRedirectURI string
 	// ScopesSupported:                   oidc.SupportedScopes,
 	// ResponseTypesSupported:            responseTypes,
 	// GrantTypesSupported:               oidc.SupportedGrantTypes,
@@ -164,6 +170,8 @@ func NewDefaultOP(ctx context.Context, config *Config, storage Storage, opOpts .
 	p.signer = NewDefaultSigner(ctx, storage, keyCh)
 	go p.ensureKey(ctx, storage, keyCh, p.timer)
 
+	p.verifier = rp.NewDefaultVerifier(config.Issuer, "", p, rp.WithIgnoreAudience())
+
 	router := CreateRouter(p, p.interceptor)
 	p.http = &http.Server{
 		Addr:    ":" + config.Port,
@@ -195,6 +203,10 @@ func (p *DefaultOP) UserinfoEndpoint() Endpoint {
 	return Endpoint(p.endpoints.Userinfo)
 }
 
+func (p *DefaultOP) EndSessionEndpoint() Endpoint {
+	return Endpoint(p.endpoints.EndSessionEndpoint)
+}
+
 func (p *DefaultOP) KeysEndpoint() Endpoint {
 	return Endpoint(p.endpoints.JwksURI)
 }
@@ -215,6 +227,23 @@ func (p *DefaultOP) HandleDiscovery(w http.ResponseWriter, r *http.Request) {
 	Discover(w, CreateDiscoveryConfig(p, p.Signer()))
 }
 
+func (p *DefaultOP) VerifySignature(ctx context.Context, jws *jose.JSONWebSignature) ([]byte, error) {
+	keyID := ""
+	for _, sig := range jws.Signatures {
+		keyID = sig.Header.KeyID
+		break
+	}
+	keySet, err := p.Storage().GetKeySet(ctx)
+	if err != nil {
+		return nil, errors.New("error fetching keys")
+	}
+	payload, err, ok := rp.CheckKey(keyID, keySet.Keys, jws)
+	if !ok {
+		return nil, errors.New("invalid kid")
+	}
+	return payload, err
+}
+
 func (p *DefaultOP) Decoder() *schema.Decoder {
 	return p.decoder
 }
@@ -257,7 +286,7 @@ func (p *DefaultOP) HandleAuthorizeCallback(w http.ResponseWriter, r *http.Reque
 func (p *DefaultOP) HandleExchange(w http.ResponseWriter, r *http.Request) {
 	reqType := r.FormValue("grant_type")
 	if reqType == "" {
-		ExchangeRequestError(w, r, ErrInvalidRequest("grant_type missing"))
+		RequestError(w, r, ErrInvalidRequest("grant_type missing"))
 		return
 	}
 	if reqType == string(oidc.GrantTypeCode) {
@@ -271,6 +300,17 @@ func (p *DefaultOP) HandleUserinfo(w http.ResponseWriter, r *http.Request) {
 	Userinfo(w, r, p)
 }
 
+func (p *DefaultOP) HandleEndSession(w http.ResponseWriter, r *http.Request) {
+	EndSession(w, r, p)
+}
+
+func (p *DefaultOP) DefaultLogoutRedirectURI() string {
+	return p.config.DefaultLogoutRedirectURI
+}
+func (p *DefaultOP) IDTokenVerifier() rp.Verifier {
+	return p.verifier
+}
+
 func (p *DefaultOP) ensureKey(ctx context.Context, storage Storage, keyCh chan<- jose.SigningKey, timer <-chan time.Time) {
 	count := 0
 	timer = time.After(0)

pkg/op/discovery.go

@@ -17,8 +17,8 @@ func CreateDiscoveryConfig(c Configuration, s Signer) *oidc.DiscoveryConfigurati
 		AuthorizationEndpoint: c.AuthorizationEndpoint().Absolute(c.Issuer()),
 		TokenEndpoint:         c.TokenEndpoint().Absolute(c.Issuer()),
 		// IntrospectionEndpoint: c.Intro().Absolute(c.Issuer()),
-		UserinfoEndpoint: c.UserinfoEndpoint().Absolute(c.Issuer()),
-		// EndSessionEndpoint: c.TokenEndpoint().Absolute(c.Issuer())(c.EndSessionEndpoint),
+		UserinfoEndpoint:   c.UserinfoEndpoint().Absolute(c.Issuer()),
+		EndSessionEndpoint: c.EndSessionEndpoint().Absolute(c.Issuer()),
 		// CheckSessionIframe: c.TokenEndpoint().Absolute(c.Issuer())(c.CheckSessionIframe),
 		JwksURI:                           c.KeysEndpoint().Absolute(c.Issuer()),
 		ScopesSupported:                   Scopes(c),

pkg/op/error.go

@@ -76,7 +76,7 @@ func AuthRequestError(w http.ResponseWriter, r *http.Request, authReq ErrAuthReq
 	http.Redirect(w, r, url, http.StatusFound)
 }
 
-func ExchangeRequestError(w http.ResponseWriter, r *http.Request, err error) {
+func RequestError(w http.ResponseWriter, r *http.Request, err error) {
 	e, ok := err.(*OAuthError)
 	if !ok {
 		e = new(OAuthError)

pkg/op/mock/storage.mock.impl.go

@@ -126,6 +126,9 @@ func (c *ConfClient) RedirectURIs() []string {
 		"custom://callback",
 	}
 }
+func (c *ConfClient) PostLogoutRedirectURIs() []string {
+	return []string{}
+}
 
 func (c *ConfClient) LoginURL(id string) string {
 	return "login?id=" + id

pkg/op/op.go

@@ -24,6 +24,7 @@ type OpenIDProvider interface {
 	HandleAuthorizeCallback(w http.ResponseWriter, r *http.Request)
 	HandleExchange(w http.ResponseWriter, r *http.Request)
 	HandleUserinfo(w http.ResponseWriter, r *http.Request)
+	HandleEndSession(w http.ResponseWriter, r *http.Request)
 	HandleKeys(w http.ResponseWriter, r *http.Request)
 	HttpHandler() *http.Server
 }
@@ -49,6 +50,7 @@ func CreateRouter(o OpenIDProvider, h HttpInterceptor) *mux.Router {
 	router.HandleFunc(o.AuthorizationEndpoint().Relative()+"/{id}", h(o.HandleAuthorizeCallback))
 	router.HandleFunc(o.TokenEndpoint().Relative(), h(o.HandleExchange))
 	router.HandleFunc(o.UserinfoEndpoint().Relative(), o.HandleUserinfo)
+	router.HandleFunc(o.EndSessionEndpoint().Relative(), h(o.HandleEndSession))
 	router.HandleFunc(o.KeysEndpoint().Relative(), o.HandleKeys)
 	return router
 }

pkg/op/session.go

@@ -1,6 +1,76 @@
 package op
 
-import "github.com/caos/oidc/pkg/oidc"
+import (
+	"context"
+	"net/http"
+
+	"github.com/caos/oidc/pkg/oidc"
+	"github.com/caos/oidc/pkg/rp"
+	"github.com/gorilla/schema"
+)
+
+type SessionEnder interface {
+	Decoder() *schema.Decoder
+	Storage() Storage
+	IDTokenVerifier() rp.Verifier
+	DefaultLogoutRedirectURI() string
+}
+
+func EndSession(w http.ResponseWriter, r *http.Request, ender SessionEnder) {
+	req, err := ParseEndSessionRequest(r, ender.Decoder())
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	session, err := ValidateEndSessionRequest(r.Context(), req, ender)
+	if err != nil {
+		RequestError(w, r, err)
+		return
+	}
+	err = ender.Storage().TerminateSession(r.Context(), session.UserID, session.Client.GetID())
+	if err != nil {
+		RequestError(w, r, ErrServerError("error terminating session"))
+		return
+	}
+	http.Redirect(w, r, session.RedirectURI, http.StatusFound)
+}
+
+func ParseEndSessionRequest(r *http.Request, decoder *schema.Decoder) (*oidc.EndSessionRequest, error) {
+	err := r.ParseForm()
+	if err != nil {
+		return nil, ErrInvalidRequest("error parsing form")
+	}
+	req := new(oidc.EndSessionRequest)
+	err = decoder.Decode(req, r.Form)
+	if err != nil {
+		return nil, ErrInvalidRequest("error decoding form")
+	}
+	return req, nil
+}
+
+func ValidateEndSessionRequest(ctx context.Context, req *oidc.EndSessionRequest, ender SessionEnder) (*EndSessionRequest, error) {
+	session := new(EndSessionRequest)
+	claims, err := ender.IDTokenVerifier().Verify(ctx, "", req.IdTokenHint)
+	if err != nil {
+		return nil, ErrInvalidRequest("id_token_hint invalid")
+	}
+	session.UserID = claims.Subject
+	session.Client, err = ender.Storage().GetClientByClientID(ctx, claims.AuthorizedParty)
+	if err != nil {
+		return nil, ErrServerError("")
+	}
+	if req.PostLogoutRedirectURI == "" {
+		session.RedirectURI = ender.DefaultLogoutRedirectURI()
+		return session, nil
+	}
+	for _, uri := range session.Client.PostLogoutRedirectURIs() {
+		if uri == req.PostLogoutRedirectURI {
+			session.RedirectURI = uri + "?state=" + req.State
+			return session, nil
+		}
+	}
+	return nil, ErrInvalidRequest("post_logout_redirect_uri invalid")
+}
 
 func NeedsExistingSession(authRequest *oidc.AuthRequest) bool {
 	if authRequest == nil {

pkg/op/storage.go

@@ -16,6 +16,8 @@ type AuthStorage interface {
 
 	CreateToken(context.Context, AuthRequest) (string, time.Time, error)
 
+	TerminateSession(context.Context, string, string) error
+
 	GetSigningKey(context.Context, chan<- jose.SigningKey, chan<- error, <-chan time.Time)
 	GetKeySet(context.Context) (*jose.JSONWebKeySet, error)
 	SaveNewKeyPair(context.Context) error
@@ -53,3 +55,9 @@ type AuthRequest interface {
 	GetSubject() string
 	Done() bool
 }
+
+type EndSessionRequest struct {
+	UserID      string
+	Client      Client
+	RedirectURI string
+}