Android-Java RSA解密

我需要从二进制字符串创建RSA算法的公钥。

我的代码是：

String pubKey = "tihq/Gk3OUs5NzP+XTRKXBwSxHtB0TWn0RREcpXEtp316tyD9DzKaIbdKexb/mRr"; byte[] keyBytes = Base64.decode(pubKey,Base64.DEFAULT); //test if is correct: ok Log.d("response keyBytes",new String(Base64.encode(keyBytes,Base64.DEFAULT))); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); X509EncodedKeySpec spec = new X509EncodedKeySpec(keyBytes); RSAPublicKey publicKey = (RSAPublicKey) keyFactory.generatePublic(spec); //PublicKey publicKey = (PublicKey) keyFactory.generatePublic(spec); 

但我有这个错误：

 java.security.spec.InvalidKeySpecException: java.lang.RuntimeException: error:0D0680A8:asn1 encoding routines:ASN1_CHECK_TLEN:wrong tag 

Answer 1

解决了。 问题是我有模数和指数，所以我必须这样做：

 String pubKey = "tihq/Gk3OUs5NzP+XTRKXBwSxHtB0TWn0RREcpXEtp316tyD9DzKaIbdKexb/mRr"; //64 caratteri String exponent = "AQAB"; byte[] keyBytes = Base64.decode(pubKey,Base64.DEFAULT); byte[] exponentByte = Base64.decode(exponent,Base64.DEFAULT); KeyFactory keyFactory = KeyFactory.getInstance("RSA"); RSAPublicKeySpec pubKeySpec = new RSAPublicKeySpec(new BigInteger(keyBytes), new BigInteger(exponentByte)); RSAPublicKey publicKey = (RSAPublicKey) keyFactory.generatePublic(pubKeySpec);