由 dawei
使用以下两种方法计算签名有什么区别？
>使用Signature.getInstance计算签名(“SHA256withRSA”)
>使用MessageDigest.getInstance(“SHA-256”)计算SHA256,并使用Signature.getInstance(“RSA”)计算摘要;得到签名？
如果它们不同,是否有一种修改方法2的方法,以便两种方法给出相同的输出？
我尝试了以下代码：
package mysha.mysha;
import java.security.MessageDigest;
import java.security.PrivateKey;
import java.security.Security;
import java.security.Signature;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
public class MySHA256 {
public static void main(String[] args) throws Exception {
//compute SHA256 first
Security.addProvider(new BouncyCastleProvider());
String s = "1234";
MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
messageDigest.update(s.getBytes());
byte[] outputDigest = messageDigest.digest();
//sign SHA256 with RSA
PrivateKey privateKey = Share.loadPk8("D:/key.pk8");
Signature rsaSignature = Signature.getInstance("RSA");
rsaSignature.initSign(privateKey);
rsaSignature.update(outputDigest);
byte[] signed = rsaSignature.sign();
System.out.println(bytesToHex(signed));
//compute SHA256withRSA as a single step
Signature rsaSha256Signature = Signature.getInstance("SHA256withRSA");
rsaSha256Signature.initSign(privateKey);
rsaSha256Signature.update(s.getBytes());
byte[] signed2 = rsaSha256Signature.sign();
System.out.println(bytesToHex(signed2));
}
public static String bytesToHex(byte[] bytes) {
final char[] hexArray = "0123456789ABCDEF".toCharArray();
char[] hexChars = new char[bytes.length * 2];
for ( int j = 0; j < bytes.length; j++ ) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
}
不过,输出不一样.
以下是我的测试键的示例输出：
方法1：61427B2A2CF1902A4B15F80156AEB09D8096BA1271F89F1919C78B18D0BABA08AA043A0037934B5AE3FC0EB7702898AC5AE96517AFD93433DF540353BCCE72A470CFA4B765D5835E7EA77743F3C4A0ABB11414B0141EF7ECCD2D5285A69728D0D0709C2537D6A772418A928B0E168F81C99B538FD25BDA7496AE8E185AC46F39
方法2：BA9039B75CA8A40DC9A7AED51E174E2B3365B2D6A1CF94DF70A00D898074A51FDD9973672DDE95CBAC39EBE4F3BA529C538ED0FF9F0A3F9A8CE203F1DFFA907DC508643906AA86DA54DFF8A90B00F5F116D13A53731384C1C5C9C4E75A3E41DAF88F74D2F1BCCF818764A4AB144A081B641C1C488AC8B194EB14BC9D1928E4EA
更新1：
根据mkl的回答,我修改了我的代码,但仍然无法正确的.我还想念什么吗？
package mysha.mysha;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.PrivateKey;
import java.security.Security;
import java.security.Signature;
import org.bouncycastle.asn1.DEROutputStream;
import org.bouncycastle.asn1.nist.NISTObjectIdentifiers;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.asn1.x509.DigestInfo;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
public class MySHA256 {
public static void main(String[] args) throws Exception {
//compute SHA256 first
Security.addProvider(new BouncyCastleProvider());
String s = "1234";
MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
messageDigest.update(s.getBytes());
byte[] outputDigest = messageDigest.digest();
AlgorithmIdentifier sha256Aid = new AlgorithmIdentifier(NISTObjectIdentifiers.id_sha256,null);
DigestInfo di = new DigestInfo(sha256Aid,outputDigest);
//sign SHA256 with RSA
PrivateKey privateKey = Share.loadPk8("D:/key.pk8");
Signature rsaSignature = Signature.getInstance("RSA");
rsaSignature.initSign(privateKey);
rsaSignature.update(di.toASN1Primitive().getEncoded());
byte[] signed = rsaSignature.sign();
System.out.println("method 1: "+bytesToHex(signed));
//compute SHA256withRSA as a single step
Signature rsaSha256Signature = Signature.getInstance("SHA256withRSA");
rsaSha256Signature.initSign(privateKey);
rsaSha256Signature.update(s.getBytes());
byte[] signed2 = rsaSha256Signature.sign();
System.out.println("method 2: "+bytesToHex(signed2));
}
public static String bytesToHex(byte[] bytes) {
final char[] hexArray = "0123456789ABCDEF".toCharArray();
char[] hexChars = new char[bytes.length * 2];
for ( int j = 0; j < bytes.length; j++ ) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
}
方法1：
675D868546777C5A9B5E74988E0CD41A46A929C1D0890B32B1FBE34F12D68F1FDB56E623294DB903F6AC60A2ADA61976B27C66056A16F5790A78168803AD2C685F9B4CF983C939305A9819CBA9D95441CD7214D40D06A98B4DDF9692A7D300DD51E808A6722A0D7C288DBD476DF4DEEBB3DAF41CFC0978F24424960F86F0284E
方法2：
BA9039B75CA8A40DC9A7AED51E174E2B3365B2D6A1CF94DF70A00D898074A51FDD9973672DDE95CBAC39EBE4F3BA529C538ED0FF9F0A3F9A8CE203F1DFFA907DC508643906AA86DA54DFF8A90B00F5F116D13A53731384C1C5C9C4E75A3E41DAF88F74D2F1BCCF818764A4AB144A081B641C1C488AC8B194EB14BC9D1928E4EA
解决方法
区别
与“SHA256withRSA”签名并计算SHA256散列并使用“RSA”(=“NONEwithRSA”)进行签名的区别首先在前一种情况下,计算出的SHA-256哈希值首先封装在DigestInfo结构中
DigestInfo ::= SEQUENCE {
digestAlgorithm DigestAlgorithm,digest OCTET STRING
}
在填充然后加密,而在后一种情况下,裸机SHA256哈希值被填充和加密.
If they are different,is there a way to modify the method 2 so that both methods give the same output?
首先,您必须在使用“NONEwithRSA”签名之前将哈希值封装在DigestInfo结构中.
RFC 3447 Section 9.2在这里说明注释1
1. For the six hash functions mentioned in Appendix B.1,the DER
encoding T of the DigestInfo value is equal to the following:
...
SHA-256: (0x)30 31 30 0d 06 09 60 86 48 01 65 03 04 02 01 05 00
04 20 || H.
使其工作
为了回应上述部分,OP更新了他的问题与更新的代码.不幸的是,它还没有为他工作.从而,
OP的代码
我执行了OP的代码(SignInSteps.java).由于他没有提供私钥,所以我使用了我自己的测试键(demo-rsa2048.p12).结果：
GreenhandOriginal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reenhandUpdated: method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method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
因此,与OP的观察结果不同,在更新的代码的情况下,签名相等.
不承担复制和粘贴错误,仍可能存在其他差异.
环境
我使用Java 8(1.8.0_20)进行了测试,其中添加了无限的管辖区域文件,BouncyCastle 1.52,1.49和1.46(由于BC API更改而进行了小的测试代码修改).
在评论中提到的OP：
The Java is JRE 8 update 66. The BouncyCastle is bcprov-jdk15on-153.jar.
所以我更新了Java,依然没有区别.