将字节数组转换回公钥

Question

我有一个转换为字节数组的公钥。我想将其转换回公钥。我关注了这个link，但遇到了错误：

Operation failed: javax.crypto.spec.SecretKeySpec incompatible with java.security.PublicKey

既然我知道它是一个公钥，有没有把它转换成Publickey而不是SecretKey。

编辑

我使用RSAPublicKeySPec 创建了一个公钥。现在没有错误但签名验证失败因为当我看到新创建的公钥的密钥材料时，它与我通过的不同。

我通过的关键材料 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

使用 RSAPublicKeySpec 将其转换为公钥后得到的密钥材料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

显然，由于密钥材料错误，验证将失败！我不明白为什么它会被改变。

但是当我使用java.security.PublicKey（匿名内部类）直接创建公钥时，密钥材料不会被更改。但是当我通过它进行验证时，我得到 wrong algorithm type 错误（我通过 RSA 作为算法）

代码片段

    PublicKey pubKey = new PublicKey() {

        private static final long serialVersionUID = 1L;

        @Override
        public String getFormat() {

            return "PKCS1";
        }

        @Override
        public byte[] getEncoded() {

            return keyMat;
        }

        @Override
        public String getAlgorithm() {

            return "SHA256withRSA"; // tried with "RSA", getting same error
        }
    };

    return pubKey;
}

Answer 1

取自Here

//Takes your byte array of the key as constructor parameter
X509EncodedKeySpec pubKeySpec = new X509EncodedKeySpec(myKeyBytes);

//Takes algorithm used to generate keys (DSA, RSA, DiffieHellman, etc.) as 1st parameter
//Takes security provider (SUN, BouncyCastle, etc.) as second parameter
KeyFactory keyFactory = KeyFactory.getInstance("DSA", "SUN");

//Creates a new PublicKey object
PublicKey pubKey = keyFactory.generatePublic(pubKeySpec);