如何从文件加载 RSA 私钥

java rsa saml

2022-08-31 15:54:31

我正在为 SAML 1.1 Assertion Consumer Service 开发测试工具。测试必须生成已签名的 SAMLResponse 并将其提交到 Base64 中编码的 ACS。ACS 必须能够使用 X509 公共证书验证已签名的邮件。

我能够构建 SAMLResponse，添加必要的断言等。但是当我尝试对对象进行签名时，我遇到了问题。以下是我当前代码的一个片段：

String certPath = "mycert.pem";
File pubCertFile = new File(certPath);
BufferedInputStream bis = null;
try {
    bis = new BufferedInputStream(new FileInputStream(pubCertFile));
} catch(FileNotFoundException e) {
    throw new Exception("Could not locate certfile at '" + certPath + "'", e);
}
CertificateFactory certFact = null;
Certificate cert = null;
try {
    certFact = CertificateFactory.getInstance("X.509");
    cert = certFact.generateCertificate(bis);
} catch(CertificateException e) {
    throw new Exception("Could not instantiate cert", e);
}
bis.close();
ArrayList<Certificate> certs = new ArrayList<Certificate>();
certs.add(cert);

String keyPath = "mykey.pem";
File privKeyFile = new File(keyPath);
try {
    bis = new BufferedInputStream(new FileInputStream(privKeyFile));
} catch(FileNotFoundException e) {
    throw new Exception("Could not locate keyfile at '" + keyPath + "'", e);
}
byte[] privKeyBytes = new byte[(int)privKeyFile.length()];
bis.read(privKeyBytes);
bis.close();
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
KeySpec ks = new PKCS8EncodedKeySpec(privKeyBytes);
RSAPrivateKey privKey = (RSAPrivateKey) keyFactory.generatePrivate(ks);

samlResponse.sign(Signature.getInstance("SHA1withRSA").toString(), privKey, certs);

该错误发生在倒数第二行。我在控制台中看到以下内容：

java.security.spec.InvalidKeySpecException: java.security.InvalidKeyException: invalid key format

虽然不是习惯或安全的，但为了这个线程，我提供了我正在使用的公共证书和私钥。当然，一旦问题得到解决，我就会重新创建新的。:)

aj@mmdev0:~/$ cat mykey.pem
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----

aj@mmdev0:~/$ cat mycert.pem
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

谢谢！

答案 1

您需要使用以下命令将私钥转换为 PKCS8 格式：

openssl pkcs8 -topk8 -inform PEM -outform DER -in private_key_file  -nocrypt > pkcs8_key

在此之后，您的java程序可以读取它。

答案 2

两件事。首先，您必须自己对文件进行 base64 解码。其次，opensl 私钥格式在 PKCS#1 中指定为 ASN.1 结构。它与java的PKCS8EncodedKeySpec不兼容，后者基于SubjectPublicKeyInfo ASN.1结构。如果您愿意使用弹跳城堡库，则可以使用弹跳城堡提供程序和弹跳城堡 PKIX库中的一些类来快速完成此操作。mykey.pemRSAPrivateKey

import java.io.BufferedReader;
import java.io.FileReader;
import java.security.KeyPair;
import java.security.Security;

import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.openssl.PEMKeyPair;
import org.bouncycastle.openssl.PEMParser;
import org.bouncycastle.openssl.jcajce.JcaPEMKeyConverter;

// ...   

String keyPath = "mykey.pem";
BufferedReader br = new BufferedReader(new FileReader(keyPath));
Security.addProvider(new BouncyCastleProvider());
PEMParser pp = new PEMParser(br);
PEMKeyPair pemKeyPair = (PEMKeyPair) pp.readObject();
KeyPair kp = new JcaPEMKeyConverter().getKeyPair(pemKeyPair);
pp.close();
samlResponse.sign(Signature.getInstance("SHA1withRSA").toString(), kp.getPrivate(), certs);