android - 从 Base64 编码的字符串生成公钥

Question

我需要使用 PublicKey 来加密 session key ，但我有公钥作为 Base64 编码字符串，所以我尝试将其转换为:

KeyFactory kf = KeyFactory.getInstance("RSA"); // or "EC" or whatever
byte[] keyBytes = _publicKey.getBytes();
byte[] publicKeyBytes = Base64.decode(keyBytes, Base64.DEFAULT);

X509EncodedKeySpec publicKeySpecs = new X509EncodedKeySpec(publicKeyBytes);
Log.v("", "X509  KS" + publicKeySpecs);
publicKey = kf.generatePublic(publicKeySpecs);

但是我得到的公钥是空值，异常是:

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

如果有人知道如何去做或有工作代码，请帮助我。

提前致谢

Answer 1

大家好，我从 Base64 编码的字符串生成了 Public Key。

经过几天的思考，这段代码对我有用。

String _publicKey= base64encoded_publickey;


    // InputStream fileInputStream = null;
    try {
        // Receiving side

        byte[] decodedBytes = Base64.decode(_publicKey, Base64.DEFAULT);

        fileInputStream = new ByteArrayInputStream(decodedBytes);

        // Print the decoded string

        String decodedString = new String(decodedBytes);


        CertificateFactory certFactory = CertificateFactory
                .getInstance(CERTIFICATE_TYPE);
        // certFactory.
        X509Certificate cert = (X509Certificate) certFactory
                .generateCertificate(fileInputStream);
        publicKey = cert.getPublicKey();
        Log.d("TAG", "Public key of the certificate:" + publicKey);


    } catch (Exception e) {
        e.printStackTrace();
        throw new RuntimeException("Could not intialize encryption module",
                e);
    } finally {
        if (keyStream != null) {
            try {
                keyStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

希望对你有帮助...谢谢...