Java 无法验证openssl使用dsa密钥签名的字符串

在我创建DSA签名消息时调整方向：

echo "foobar" > foo.txt
openssl dgst -dss1 -sign dsa_priv.pem foo.txt > sigfile.bin

directions实际上使用了foo.sha1而不是foo.txt，其中foo.sha1是由

sha1sum

生成的，但签名哈希似乎有点多余，因为DSA本身应该进行哈希运算

所以，不管怎样，我做到了。以下是我使用的私钥（我专门为测试目的生成它）：

下面是sigfile.bin的十六进制编码输出：

302c021456d7e7da10d1538a6cd45dcb2b0ce15c28bac03402147e973a4de1e92e8a87ed5218c797952a3f854df5

我现在正试图用BouncyCastle在Java中验证这一点，但无法做到。以下是我的Java代码：

import java.io.StringReader;
import org.bouncycastle.openssl.PEMReader;
import java.security.interfaces.DSAPublicKey;
import org.bouncycastle.crypto.params.DSAPublicKeyParameters;

import org.bouncycastle.crypto.signers.DSADigestSigner;
import org.bouncycastle.crypto.signers.DSASigner;
import org.bouncycastle.crypto.digests.SHA1Digest;
import org.bouncycastle.crypto.params.DSAParameters;

public class DSA
{
    public static void main(String[] args)
    throws Exception
    {
        byte[] message = "foobar".getBytes();
        byte[] signature = hexStringToByteArray("302c021456d7e7da10d1538a6cd45dcb2b0ce15c28bac03402147e973a4de1e92e8a87ed5218c797952a3f854df5");

            String key = "-----BEGIN PUBLIC KEY-----\n" +
                "MIIBuDCCASwGByqGSM44BAEwggEfAoGBAOwYAcAzXpuw+XCXuNp5zhAzKdhrRguI\n" +
                "uI5kLia8fhRb+1EnFPNpXt4fUS2c/0P0nvzH/TvApizzMkRYJea6rRSW5B+MDjv6\n" +
                "lvrxv+5xBM15kdug033mgSL7wEJIrTLwbe5/djz2oe+pr1KLqs/fvgyKcQyttUWb\n" +
                "5SmwZ+UVx3zfAhUAu0kA2L6VgbvEwpD9sTj5tLyB6Y0CgYEA5GjC+KsPsAH3HZKl\n" +
                "2IwTjX47iNVHyuzr4ZcyXceJ/pi3WR6bQJ6tpf1I2jIE0DOMPlNUwYh0aWBGvoY2\n" +
                "t4d5cwZaW90OS8IAIRFkQS0ywpmJyb7KXqRHwAYdMID88GW0d/KsVB3if0j/9QOo\n" +
                "jhGOrO+kJcZBxUSxINgIIEYFAlEDgYUAAoGBALnHTAZlpoLJZuSBVtnMuRM3cSX4\n" +
                "3IkE9w9FveDV1jX5mmfK7yBVpQFV8eVJfk91ERQ4Dn6ePLUv2dRIt4a0S0qHqadg\n" +
                "zyoFyqkmmUi1kNLyixtRqh+m2gXx0t63HEpZDbEPppdpnlppZquVQh7TyrKSXW9M\n" +
                "TzUkQjFI9UY7kZeK\n" +
                "-----END PUBLIC KEY-----";
        PEMReader reader = new PEMReader(new StringReader(key));
        DSAPublicKey decoded = (DSAPublicKey) reader.readObject();

        DSADigestSigner dsa = new DSADigestSigner(new DSASigner(), new SHA1Digest());
        DSAParameters params = new DSAParameters(
            decoded.getParams().getP(),
            decoded.getParams().getQ(),
            decoded.getParams().getG()
        );
        DSAPublicKeyParameters publickey = new DSAPublicKeyParameters(decoded.getY(), params);
        dsa.init(false, publickey);
        dsa.update(message, 0, message.length);
        boolean result = dsa.verifySignature(signature);

        System.out.println(result ? "good" : "bad");
    }

    public static byte[] hexStringToByteArray(String s)
    {
        int len = s.length();
        byte[] data = new byte[len / 2];
        for (int i = 0; i < len; i += 2)
        {
            data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
                + Character.digit(s.charAt(i+1), 16));
        }
        return data;
    }
}

（Unix）

echo

输出其参数，如果有多个参数，则以空格分隔，加上换行符。使用

“foobar\n”

作为验证数据。或者对

printf“%s”foobar>foo.txt的结果进行签名，该结果可移植地忽略换行符；有些版本的
echo
支持
-n
为此，有些旧版本使用
\c
，有些根本不支持

自版本150（2013）起的FYI BouncyCastle不再具有
org.BouncyCastle.openssl.PEMReader
；相反，您需要
PEMParser
，它返回
org.bouncycastle.asn1.x509.SubjectPublicKeyInfo
，可以通过
org.bouncycastle.openssl.jcajce.JcaPEMKeyConverter
或
KeyFactory.getInstance（alg）.生成PublicKey（新的X509EncodedKey（spki.getEncoded（）））
这就是JcaPEMKeyConverter的实际功能

o您可以使用
org.bouncycastle.jcajce.provider.asymetric.dsa.DSAUtil.generatePubliceParameter
替换对参数片段的篡改；这就是BC提供程序接口（与轻量级接口相反）的功能。当然，您也可以首先使用JCA，而实际上根本不需要BC，因为OpenSSL公钥格式（与privatekey不同）与基本Java加密一致兼容

另外，顺便说一句，openssl dgst

只需要通过版本0.9.8进行

-dss1

黑客攻击；自2010年1.0.0版发布以来（但由于实际或担心不兼容，许多发行版和产品没有立即升级），您只需要

-sha1

和DSA公钥

import java.io.StringReader;
import org.bouncycastle.openssl.PEMReader;
import java.security.interfaces.DSAPublicKey;
import org.bouncycastle.crypto.params.DSAPublicKeyParameters;

import org.bouncycastle.crypto.signers.DSADigestSigner;
import org.bouncycastle.crypto.signers.DSASigner;
import org.bouncycastle.crypto.digests.SHA1Digest;
import org.bouncycastle.crypto.params.DSAParameters;

public class DSA
{
    public static void main(String[] args)
    throws Exception
    {
        byte[] message = "foobar".getBytes();
        byte[] signature = hexStringToByteArray("302c021456d7e7da10d1538a6cd45dcb2b0ce15c28bac03402147e973a4de1e92e8a87ed5218c797952a3f854df5");

            String key = "-----BEGIN PUBLIC KEY-----\n" +
                "MIIBuDCCASwGByqGSM44BAEwggEfAoGBAOwYAcAzXpuw+XCXuNp5zhAzKdhrRguI\n" +
                "uI5kLia8fhRb+1EnFPNpXt4fUS2c/0P0nvzH/TvApizzMkRYJea6rRSW5B+MDjv6\n" +
                "lvrxv+5xBM15kdug033mgSL7wEJIrTLwbe5/djz2oe+pr1KLqs/fvgyKcQyttUWb\n" +
                "5SmwZ+UVx3zfAhUAu0kA2L6VgbvEwpD9sTj5tLyB6Y0CgYEA5GjC+KsPsAH3HZKl\n" +
                "2IwTjX47iNVHyuzr4ZcyXceJ/pi3WR6bQJ6tpf1I2jIE0DOMPlNUwYh0aWBGvoY2\n" +
                "t4d5cwZaW90OS8IAIRFkQS0ywpmJyb7KXqRHwAYdMID88GW0d/KsVB3if0j/9QOo\n" +
                "jhGOrO+kJcZBxUSxINgIIEYFAlEDgYUAAoGBALnHTAZlpoLJZuSBVtnMuRM3cSX4\n" +
                "3IkE9w9FveDV1jX5mmfK7yBVpQFV8eVJfk91ERQ4Dn6ePLUv2dRIt4a0S0qHqadg\n" +
                "zyoFyqkmmUi1kNLyixtRqh+m2gXx0t63HEpZDbEPppdpnlppZquVQh7TyrKSXW9M\n" +
                "TzUkQjFI9UY7kZeK\n" +
                "-----END PUBLIC KEY-----";
        PEMReader reader = new PEMReader(new StringReader(key));
        DSAPublicKey decoded = (DSAPublicKey) reader.readObject();

        DSADigestSigner dsa = new DSADigestSigner(new DSASigner(), new SHA1Digest());
        DSAParameters params = new DSAParameters(
            decoded.getParams().getP(),
            decoded.getParams().getQ(),
            decoded.getParams().getG()
        );
        DSAPublicKeyParameters publickey = new DSAPublicKeyParameters(decoded.getY(), params);
        dsa.init(false, publickey);
        dsa.update(message, 0, message.length);
        boolean result = dsa.verifySignature(signature);

        System.out.println(result ? "good" : "bad");
    }

    public static byte[] hexStringToByteArray(String s)
    {
        int len = s.length();
        byte[] data = new byte[len / 2];
        for (int i = 0; i < len; i += 2)
        {
            data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
                + Character.digit(s.charAt(i+1), 16));
        }
        return data;
    }
}

openssl dgst -dss1 -verify dsa_pub.pem -signature sigfile.bin foo.txt