如何在充氣城堡 (Java) 中讀取 AsymmetricKeyParameter 的 DER DSA 私鑰

Question

如何將帶有私有 DSA 密鑰（4096 位）的 DER 文件讀入 AsymmetricKeyParameter 以在 DSASigner 中使用？

我嘗試了以下代碼：

 byte[] privateKeyBytes = FileUtils.readFileToByteArray(new File(
                    "sign-key-private.der"));
 AsymmetricKeyParameter privateKey = PrivateKeyFactory
                    .createKey(privateKeyBytes);

結果是一個例外：

java.lang.IllegalArgumentException: unknown object in getInstance: org.bouncycastle.asn1.ASN1Integer
    at org.bouncycastle.asn1.ASN1Sequence.getInstance(Unknown Source)
    at org.bouncycastle.asn1.x509.AlgorithmIdentifier.getInstance(Unknown Source)
    at org.bouncycastle.asn1.pkcs.PrivateKeyInfo.<init>(Unknown Source)
    at org.bouncycastle.asn1.pkcs.PrivateKeyInfo.getInstance(Unknown Source)
    at org.bouncycastle.crypto.util.PrivateKeyFactory.createKey(Unknown Source)
    at test.security.core.Program.main(Program.java:41)

Answer 1

我最終使用的解決方法是將密鑰轉換為PEM格式並使用以下命令：

 @Cleanup
 FileReader privateKeyReader = new FileReader(new File("key.pem"));
 @Cleanup
 PEMParser parser = new PEMParser(privateKeyReader);

 PEMKeyPair keyPair = (PEMKeyPair) parser.readObject();
 AsymmetricKeyParameter privateKey = PrivateKeyFactory
     .createKey(keyPair.getPrivateKeyInfo());
 AsymmetricKeyParameter publicKey = PublicKeyFactory
     .createKey(keyPair.getPublicKeyInfo());

Answer 2

byte[] privateKeyBytes = FileUtils.readFileToByteArray(new File("sign-key-private.der"));
KeyFactory kf = KeyFactory.getInstance("RSA", "BC");
PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
RSAPrivateKey rsaKey = (RSAPrivateKey) kf.generatePrivate(keySpec);
AsymmetricKeyParameter privateKeyParameter = new RSAKeyParameters(true, rsaKey.getModulus(), rsaKey.getPrivateExponent());