java - 无效 key 异常 : Invalid key format java

Question

我正在尝试从 Vault 中检索公钥。它作为 secret 存储。
我正在尝试将检索到的字符串转换为公钥以验证签名。
示例公钥字符串如下所示

-----BEGIN PUBLIC KEY----- MIIBITANBgkqhkiG9w0BAQEFAAOCAQ4AMIIBCQKCAQBWeqVZ8Ub/o4VQ8nnm888B/Ydqv2IN5bObxupZ7njMKuT/WPgwlK8+Wc0Xjhy82E51XW6E4/0um8sIQ1cxvoSOQsrfkRagD+O9OrjQbb2TqrilDDhFx9EGjXuZpR3brDUufCG6SkypqiKSaMuoVoaxc82TZ1uAIp5OSroWt1IdUkvam24X/7zDIf1l8XWCmbfCDrBb73hBYA4MgTjsSckC5nz+GLcWTfz0wze4lwHCi1KYFv+1+WcYHWPLbqLtc8nzVqkuP5Ne/9HAFkaEAIw5fKLccksaT/TLyIcrALcfuABlgX1yeBulVcbTAp+WiYRvo9+FKK23pbwkh+uy0tq1AgMBAAE=-----END PUBLIC KEY-----

我在我的 secret 值中添加了相同的内容，并且没有格式化。
但是，使用下面的代码，我在行中遇到错误 InvalidKeyException: INVALID KEY FORMAT

 PublicKey publicKey = fact.generatePublic(pubKeySpec);

这是代码:

            String publicKeyAsString = secretClient.getSecret("key-name").getValue();
    
            byte[] keyContentAsBytes = publicKeyAsString.getBytes();
    
            KeyFactory fact = KeyFactory.getInstance("RSA");
            X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(keyContentAsBytes);
            PublicKey publicKey = fact.generatePublic(pubKeySpec);

使用堆栈跟踪编辑:

Caused by: java.security.InvalidKeyException: invalid key format
    at sun.security.x509.X509Key.decode(X509Key.java:386) ~[?:?]
    at sun.security.x509.X509Key.decode(X509Key.java:401) ~[?:?]
    at sun.security.rsa.RSAPublicKeyImpl.<init>(RSAPublicKeyImpl.java:122) ~[?:?]
    at sun.security.rsa.RSAKeyFactory.generatePublic(RSAKeyFactory.java:330) ~[?:?]
    at sun.security.rsa.RSAKeyFactory.engineGeneratePublic(RSAKeyFactory.java:235) ~[?:?]

编辑:用于测试的公钥:

-----BEGIN PUBLIC KEY----- MIIBITANBgkqhkiG9w0BAQEFAAOCAQ4AMIIBCQKCAQBWeqVZ8Ub/o4VQ8nnm888B/Ydqv2IN5bObxupZ7njMKuT/WPgwlK8+Wc0Xjhy82E51XW6E4/0um8sIQ1cxvoSOQsrfkRagD+O9OrjQbb2TqrilDDhFx9EGjXuZpR3brDUufCG6SkypqiKSaMuoVoaxc82TZ1uAIp5OSroWt1IdUkvam24X/7zDIf1l8XWCmbfCDrBb73hBYA4MgTjsSckC5nz+GLcWTfz0wze4lwHCi1KYFv+1+WcYHWPLbqLtc8nzVqkuP5Ne/9HAFkaEAIw5fKLccksaT/TLyIcrALcfuABlgX1yeBulVcbTAp+WiYRvo9+FKK23pbwkh+uy0tq1AgMBAAE=-----END PUBLIC KEY-----

的值PublicKeyAsString 如下所示:

-----BEGIN PUBLIC KEY----- MIIBITANBgkqhkiG9w0BAQEFAAOCAQ4AMIIBCQKCAQBWeqVZ8Ub/o4VQ8nnm888B/Ydqv2IN5bObxupZ7njMKuT/WPgwlK8+Wc0Xjhy82E51XW6E4/0um8sIQ1cxvoSOQsrfkRagD+O9OrjQbb2TqrilDDhFx9EGjXuZpR3brDUufCG6SkypqiKSaMuoVoaxc82TZ1uAIp5OSroWt1IdUkvam24X/7zDIf1l8XWCmbfCDrBb73hBYA4MgTjsSckC5nz+GLcWTfz0wze4lwHCi1KYFv+1+WcYHWPLbqLtc8nzVqkuP5Ne/9HAFkaEAIw5fKLccksaT/TLyIcrALcfuABlgX1yeBulVcbTAp+WiYRvo9+FKK23pbwkh+uy0tq1AgMBAAE= -----END PUBLIC KEY-----

Answer 1

最初我认为您的问题与 Azure KeyVault Secret API 返回的信息类型有关，通常编码为 base 64。
在这种情况下，您需要在尝试执行实际的 key Material 处理之前执行适当的 base 64 解码:

String publicKeyAsString = secretClient.getSecret("key-name").getValue();
    
byte[] keyContentAsBytes = Base64.getDecoder().decode(publicKeyAsString);

但似乎 Azure 客户端以纯文本形式向您提供信息。
在这种情况下， secret 是一个 pem 编码的公钥。
标准 KeyFactory将不允许您开箱即用地处理返回的信息，但可以稍作修改。例如，尝试以下操作:

// Actually
// String publicKeyAsString = secretClient.getSecret("key-name").getValue();

String publicKeyAsString =
    "-----BEGIN PUBLIC KEY-----\n" +
    "MIIBITANBgkqhkiG9w0BAQEFAAOCAQ4AMIIBCQKCAQBWeqVZ8Ub/o4VQ8nnm888B\n" +
    "/Ydqv2IN5bObxupZ7njMKuT/WPgwlK8+Wc0Xjhy82E51XW6E4/0um8sIQ1cxvoSO\n" +
    "QsrfkRagD+O9OrjQbb2TqrilDDhFx9EGjXuZpR3brDUufCG6SkypqiKSaMuoVoax\n" +
    "c82TZ1uAIp5OSroWt1IdUkvam24X/7zDIf1l8XWCmbfCDrBb73hBYA4MgTjsSckC\n" +
    "5nz+GLcWTfz0wze4lwHCi1KYFv+1+WcYHWPLbqLtc8nzVqkuP5Ne/9HAFkaEAIw5\n" +
    "fKLccksaT/TLyIcrALcfuABlgX1yeBulVcbTAp+WiYRvo9+FKK23pbwkh+uy0tq1\n" +
    "AgMBAAE=\n" +
    "-----END PUBLIC KEY-----";

String publicKeyPem = publicKeyAsString
    .replace("-----BEGIN PUBLIC KEY-----", "")
    .replaceAll("\\n", "")
    .replace("-----END PUBLIC KEY-----", "");

byte[] keyContentAsBytes =  Base64.getDecoder().decode(publicKeyPem);

try {
  KeyFactory fact = KeyFactory.getInstance("RSA");
  X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(keyContentAsBytes);
  PublicKey publicKey = fact.generatePublic(pubKeySpec);
  System.out.println(publicKey);
}catch (Throwable t) {
  t.printStackTrace();
}

或者更好，使用 BouncyCaSTLe PemReader对于这个任务:

try (
    Reader reader = new StringReader(publicKeyAsString);
    PemReader pemReader = new PemReader(reader)
) {
  KeyFactory fact = KeyFactory.getInstance("RSA");
  PemObject pemObject = pemReader.readPemObject();
  byte[] keyContentAsBytesFromBC = pemObject.getContent();
  X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(keyContentAsBytesFromBC);
  PublicKey publicKey = fact.generatePublic(pubKeySpec);
  System.out.println(publicKey);
} catch (Throwable t) {
  t.printStackTrace();
}

请注意，我在变量 publicKeyAsString 的定义中包含了几个回车符。 ，为了让程序处理信息，它们是必要的。
请验证 Azure 是否以类似的方式返回 pem 编码的 key :如果不是这种情况，则很可能是问题的原因。
此外，请注意 Azure KeyVault 在您上传 secret 时会返回该 secret 这一事实:也许问题出在那里。请尝试以下操作:

PublicKey publicKey = ...
StringWriter writer = new StringWriter();
PemWriter pemWriter = new PemWriter(writer);
pemWriter.writeObject(
  new PemObject("PUBLIC KEY", publicKey.getEncoded())
);
pemWriter.flush();
pemWriter.close();
String publicKeyAsString = writer.toString();
// Upload to Azure KeyVault