Fix occur panic when invalid PublicKey parsing.

ActivityPub/models.go

@@ -82,6 +82,10 @@ func (actor *Actor) RetrieveRemoteActor(url string, uaString string, cache *cach
 	}
 	defer resp.Body.Close()
 
+	if resp.StatusCode != 200 {
+		return errors.New(resp.Status)
+	}
+
 	data, _ := ioutil.ReadAll(resp.Body)
 	err = json.Unmarshal(data, &actor)
 	if err != nil {

KeyLoader/keyloader.go

@@ -25,6 +25,9 @@ func ReadPrivateKeyRSAfromPath(path string) (*rsa.PrivateKey, error) {
 func ReadPublicKeyRSAfromString(pemString string) (*rsa.PublicKey, error) {
 	pemByte := []byte(pemString)
 	decoded, _ := pem.Decode(pemByte)
+	defer func() {
+		recover()
+	}()
 	keyInterface, err := x509.ParsePKIXPublicKey(decoded.Bytes)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)

decode.go

@@ -33,6 +33,9 @@ func decodeActivity(request *http.Request) (*activitypub.Activity, *activitypub.
 		return nil, nil, nil, err
 	}
 	PubKey, err := keyloader.ReadPublicKeyRSAfromString(remoteActor.PublicKey.PublicKeyPem)
+	if PubKey == nil {
+		return nil, nil, nil, errors.New("Failed parse PublicKey from string")
+	}
 	if err != nil {
 		return nil, nil, nil, err
 	}