首页 > 解决方案 > 从 PKCS1 密钥获取 RSA 公钥

问题描述

我以以下格式获取我的公钥,我需要使用 java 使用此密钥加密一些数据

-----BEGIN RSA PUBLIC KEY----- MIGJAoGBAKDZp/3e4w1nJA/ImDMgaGowWfTnhlFkrvS86LBc6wh1/zBRt51/2F/o/ZzaA5mZ nx5YMlhDOf3vHyzyO4KzYlG8md3RQU7eKQQDxgRfW1v0f7WVQoC2Dxbupyz0JVV4jQStYUYW ifGsh76wI3rkzlq3F2Ea/+jqMxX/AZOO30tBAgMBAAE= -----END RSA PUBLIC KEY-----

标签: javaencryptionrsapkcs#1

解决方案


您可以使用BouncyCastle库来实现这一点。您的密钥在 PEM fromat 中。要阅读它,您可以使用PEMParser

private static PublicKey readPublicKey(String path) throws InvalidKeySpecException, NoSuchAlgorithmException, IOException {
    PEMParser pemParser = new PEMParser(new FileReader(path));
    Object object = pemParser.readObject();
    SubjectPublicKeyInfo subjectPublicKeyInfo = (SubjectPublicKeyInfo) object;

    RSAKeyParameters rsa = (RSAKeyParameters) PublicKeyFactory.createKey(subjectPublicKeyInfo);

    RSAPublicKeySpec rsaSpec = new RSAPublicKeySpec(rsa.getModulus(), rsa.getExponent());
    KeyFactory kf = KeyFactory.getInstance("RSA", new BouncyCastleProvider());
    return kf.generatePublic(rsaSpec);
}

然后用这个密钥加密:

PublicKey publicKey = readPublicKey("src/main/resources/key.pem");

String dataToEncrypt = "myMessage";
Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", new BouncyCastleProvider());
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
byte[] encrypted = cipher.doFinal(dataToEncrypt.getBytes(StandardCharsets.UTF_8));

使用版本测试:bcpkix-jdk15onbcprov-jdk15on


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