java - 将 CRYPT_RSA_PUBLIC_FORMAT_PKCS1 从 php 转换为 Java 中的 RSA 公钥

Question

我正在尝试将 RSA 公钥从 PHP 发送到 Java(Android)。我的 PHP 代码如下所示:

function __construct() {
        $rsa = new Crypt_RSA();
        $rsa->setHash('sha1');
        $rsa->setMGFHash('sha1');
        $rsa->setEncryptionMode(CRYPT_RSA_ENCRYPTION_OAEP);
        $rsa->setPrivateKeyFormat(CRYPT_RSA_PRIVATE_FORMAT_PKCS1);
        $rsa->setPublicKeyFormat(CRYPT_RSA_PUBLIC_FORMAT_PKCS1);

        // Code to Generate the public key and private key

        $keys = $rsa->createKey(1024);

        extract($keys);

        // Base 64 encode Public and Private key
        $this->rsa = $rsa;
        $this->keys = $keys;
        $this->publicKeyBase = base64_encode($publickey);
        $this->privateKeyBase = base64_encode($privatekey);
}

然后我将 $this->publicKeyBase 发送到我的 Android 应用程序。在 Java 中，我得到这样的编码字符串:

LS0tLS1CRUdJTiBSU0EgUFVCTElDIEtFWS0tLS0tDQpNSUdKQW9HQkFMQzluUkdhVGsybzlJTW5YVW0vWWRVHMrTFplc09GUi9VYkU2K21hWDlwbGIwRW11RzZacHBMDQpoV2dRbUNBYmV6aW9Sc HZNL0lVZHZWczZ6ZmFKaDRGTnFaRXo0cWd0V0ovaFpUU2RudlFIMlI3cWF0TEY0c0ZSDQpDbWNNVDZBdnYvdDJnR1liMW4vY1lhb01ralNOd1RFdTJBSU45djg0Skk2ZWhmOGNST0RMQWdNQkFBRT0NCi0t LS0tRU5EIFJTQSBQVUJMSUMgS0VZLS0tLS0=

解码后，它看起来像这样:

-----BEGIN RSA PUBLIC KEY-----
    MIGJAoGBALC9nRGaTk2o9IMnXUm/YdU0s+LZesOFR/UbE6+maX9plb0EmuG6ZppL
    hWgQmCAbezioRpvM/IUdvVs6zfaJh4FNqZEz4qgtWJ/hZTSdnvQH2R7qatLF4sFR
    CmcMT6Avv/t2gGYb1n/cYaoMkjSNwTEu2AIN9v84JI6ehf8cRODLAgMBAAE=
    -----END RSA PUBLIC KEY-----

如何将其转换为可在 Android 应用程序中使用的公钥。在网上看到了很多例子，但它们不起作用，我的 java 代码(如下)似乎也不起作用。有什么可能的解决方案吗？

private static PublicKey getPublicKeyFromPemFormat(String PEMString, boolean isFilePath) throws IOException, NoSuchAlgorithmException,
            InvalidKeySpecException {

        BufferedReader pemReader = null;
        if (isFilePath) {
            pemReader = new BufferedReader(new InputStreamReader(
                    new FileInputStream(PEMString)));
        } else {
            pemReader = new BufferedReader(new InputStreamReader(
                    new ByteArrayInputStream(PEMString.getBytes("UTF-8"))));
        }
        StringBuffer content = new StringBuffer();
        String line = null;

        while ((line = pemReader.readLine()) != null) {
            if (line.indexOf("-----BEGIN RSA PUBLIC KEY-----") != -1) {
                while ((line = pemReader.readLine()) != null) {
                    if (line.indexOf("-----END RSA PUBLIC KEY-----") != -1) {
                        break;
                    }
                    content.append(line.trim());
                }
                break;
            }
        }
        if (line == null) {
            throw new IOException("PUBLIC KEY" + " not found");
        }
        Log.i("PUBLIC KEY: ", "PEM content = : " + content.toString());

        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        return keyFactory.generatePublic(new X509EncodedKeySpec(Base64.decode(content.toString(), Base64.DEFAULT)));

    }

<小时/>

new X509EncodedKeySpec(Base64.decode(content.toString(), Base64.DEFAULT)) throws an Invalid KeySpec Exception.

Answer 1

文档有点令人困惑，但是通过查看从第 950 行开始的方法 _convertPublicKey($n, $e) 的 source code ，似乎 if $publicKeyFormat == PUBLIC_FORMAT_PKCS8 那么输出格式应该是与 Java 的 X509EncodedKeySpec 类兼容的格式。