Pass the raw token along in the Authorization header

This makes it work with the kubernetes dashboard.

oauthproxy.go

@@ -683,6 +683,7 @@ func (p *OAuthProxy) Authenticate(rw http.ResponseWriter, req *http.Request) int
 	}
 	if p.PassAccessToken && session.AccessToken != "" {
 		req.Header["X-Forwarded-Access-Token"] = []string{session.AccessToken}
+		req.Header["Authorization"] = []string{"Bearer " + session.RawIDToken}
 	}
 	if session.Email == "" {
 		rw.Header().Set("GAP-Auth", session.User)

providers/oidc.go

@@ -67,6 +67,7 @@ func (p *OIDCProvider) Redeem(redirectURL, code string) (s *SessionState, err er
 		RefreshToken: token.RefreshToken,
 		ExpiresOn:    token.Expiry,
 		Email:        claims.Email,
+		RawIDToken:   rawIDToken,
 	}
 
 	return

providers/session_state.go

@@ -15,6 +15,7 @@ type SessionState struct {
 	RefreshToken string
 	Email        string
 	User         string
+	RawIDToken   string
 }
 
 func (s *SessionState) IsExpired() bool {
@@ -72,7 +73,14 @@ func (s *SessionState) EncryptedString(c *cookie.Cipher) (string, error) {
 			return "", err
 		}
 	}
-	return fmt.Sprintf("%s|%s|%d|%s", s.userOrEmail(), a, s.ExpiresOn.Unix(), r), nil
+	rawIDToken := s.RawIDToken
+	if rawIDToken != "" {
+		rawIDToken, err = c.Encrypt(rawIDToken)
+		if err != nil {
+			return "", err
+		}
+	}
+	return fmt.Sprintf("%s|%s|%d|%s|%s", s.userOrEmail(), a, s.ExpiresOn.Unix(), r, rawIDToken), nil
 }
 
 func DecodeSessionState(v string, c *cookie.Cipher) (s *SessionState, err error) {
@@ -85,8 +93,8 @@ func DecodeSessionState(v string, c *cookie.Cipher) (s *SessionState, err error)
 		return &SessionState{User: v}, nil
 	}
 
-	if len(chunks) != 4 {
-		err = fmt.Errorf("invalid number of fields (got %d expected 4)", len(chunks))
+	if len(chunks) != 5 {
+		err = fmt.Errorf("invalid number of fields (got %d expected 5)", len(chunks))
 		return
 	}
 
@@ -111,5 +119,12 @@ func DecodeSessionState(v string, c *cookie.Cipher) (s *SessionState, err error)
 	}
 	ts, _ := strconv.Atoi(chunks[2])
 	s.ExpiresOn = time.Unix(int64(ts), 0)
+
+	if c != nil && chunks[4] != "" {
+		s.RawIDToken, err = c.Decrypt(chunks[4])
+		if err != nil {
+			return nil, err
+		}
+	}
 	return
 }