国密即国家密码局认定的国产密码算法。主要有SM1,SM2,SM3,SM4。密钥长度和分组长度均为128位。
SM1 为对称加密。其加密强度与AES相当。该算法不公开,调用该算法时,需要通过加密芯片的接口进行调用。
SM2为非对称加密,基于ECC。该算法已公开。由于该算法基于ECC,故其签名速度与秘钥生成速度都快于RSA。ECC 256位(SM2采用的就是ECC 256位的一种)安全强度比RSA 2048位高,但运算速度快于RSA。
SM3 消息摘要。可以用MD5作为对比理解。该算法已公开。校验结果为256位。
SM4 无线局域网标准(WAPI)的分组数据算法。对称加密,密钥长度和分组长度均为128位。
由于SM1、SM4加解密的分组大小为128bit,故对消息进行加解密时,若消息长度过长,需要进行分组,要消息长度不足,则要进行填充。
重点:国密算法只是公布了算法,并没有给出具体语言的实现,因此需要各个语言根据算法去自己实现。
依赖类库:
talk is cheap,show me the code
using Org.BouncyCastle.Asn1.GM;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Digests;
using Org.BouncyCastle.Crypto.Engines;
using Org.BouncyCastle.Crypto.Generators;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Crypto.Signers;
using Org.BouncyCastle.Math;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Utilities.Encoders;
using System;
using System.Text.RegularExpressions;
public class SM2Service
{
public SM2Service(string pubkey, string privkey, Mode mode)
{
if (pubkey != null) this.pubkey = Decode(pubkey);
if (privkey != null) this.privkey = Decode(privkey);
this.mode = mode;
}
public SM2Service(byte[] pubkey, byte[] privkey, Mode mode)
{
this.pubkey = pubkey;
this.privkey = privkey;
this.mode = mode;
}
byte[] pubkey;
byte[] privkey;
Mode mode;
ICipherParameters _privateKeyParameters;
ICipherParameters PrivateKeyParameters
{
get
{
var r = _privateKeyParameters;
if (r == null) r = _privateKeyParameters = new ECPrivateKeyParameters(new BigInteger(1, privkey), new ECDomainParameters(GMNamedCurves.GetByName("SM2P256V1")));
return r;
}
}
ICipherParameters _publicKeyParameters;
ICipherParameters PublicKeyParameters
{
get
{
var r = _publicKeyParameters;
if (r == null)
{
var x9ec = GMNamedCurves.GetByName("SM2P256V1");
r = _publicKeyParameters = new ECPublicKeyParameters(x9ec.Curve.DecodePoint(pubkey), new ECDomainParameters(x9ec));
}
return r;
}
}
public static void GenerateKeyHex(out string pubkey, out string privkey)
{
GenerateKey(out var a, out var b);
pubkey = Hex.ToHexString(a);
privkey = Hex.ToHexString(b);
}
public static void GenerateKey(out byte[] pubkey, out byte[] privkey)
{
var g = new ECKeyPairGenerator();
g.Init(new ECKeyGenerationParameters(new ECDomainParameters(GMNamedCurves.GetByName("SM2P256V1")), new SecureRandom()));
var k = g.GenerateKeyPair();
pubkey = ((ECPublicKeyParameters)k.Public).Q.GetEncoded(false);
privkey = ((ECPrivateKeyParameters)k.Private).D.ToByteArray();
}
public byte[] Decrypt(byte[] data)
{
if (mode == Mode.C1C3C2) data = C132ToC123(data);
var sm2 = new SM2Engine(new SM3Digest());
sm2.Init(false, this.PrivateKeyParameters);
return sm2.ProcessBlock(data, 0, data.Length);
}
public byte[] Encrypt(byte[] data)
{
var sm2 = new SM2Engine(new SM3Digest());
sm2.Init(true, new ParametersWithRandom(PublicKeyParameters));
data = sm2.ProcessBlock(data, 0, data.Length);
if (mode == Mode.C1C3C2) data = C123ToC132(data);
return data;
}
public byte[] Sign(byte[] msg, byte[] id = null)
{
var sm2 = new SM2Signer(new SM3Digest());
ICipherParameters cp;
if (id != null) cp = new ParametersWithID(new ParametersWithRandom(PrivateKeyParameters), id);
else cp = new ParametersWithRandom(PrivateKeyParameters);
sm2.Init(true, cp);
sm2.BlockUpdate(msg, 0, msg.Length);
return sm2.GenerateSignature();
}
public bool VerifySign(byte[] msg, byte[] signature, byte[] id = null)
{
var sm2 = new SM2Signer(new SM3Digest());
ICipherParameters cp;
if (id != null) cp = new ParametersWithID(PublicKeyParameters, id);
else cp = PublicKeyParameters;
sm2.Init(false, cp);
sm2.BlockUpdate(msg, 0, msg.Length);
return sm2.VerifySignature(signature);
}
static byte[] C123ToC132(byte[] c1c2c3)
{
var gn = GMNamedCurves.GetByName("SM2P256V1");
int c1Len = (gn.Curve.FieldSize + 7) / 8 * 2 + 1; //sm2p256v1的这个固定65。可看GMNamedCurves、ECCurve代码。
int c3Len = 32; //new SM3Digest().getDigestSize();
byte[] result = new byte[c1c2c3.Length];
Array.Copy(c1c2c3, 0, result, 0, c1Len); //c1
Array.Copy(c1c2c3, c1c2c3.Length - c3Len, result, c1Len, c3Len); //c3
Array.Copy(c1c2c3, c1Len, result, c1Len + c3Len, c1c2c3.Length - c1Len - c3Len); //c2
return result;
}
static byte[] C132ToC123(byte[] c1c3c2)
{
var gn = GMNamedCurves.GetByName("SM2P256V1");
int c1Len = (gn.Curve.FieldSize + 7) / 8 * 2 + 1;
int c3Len = 32; //new SM3Digest().getDigestSize();
byte[] result = new byte[c1c3c2.Length];
Array.Copy(c1c3c2, 0, result, 0, c1Len); //c1: 0->65
Array.Copy(c1c3c2, c1Len + c3Len, result, c1Len, c1c3c2.Length - c1Len - c3Len); //c2
Array.Copy(c1c3c2, c1Len, result, c1c3c2.Length - c3Len, c3Len); //c3
return result;
}
static byte[] Decode(string key)
{
return Regex.IsMatch(key, "^[0-9a-f]+$", RegexOptions.IgnoreCase) ? Hex.Decode(key) : Convert.FromBase64String(key);
}
public enum Mode
{
C1C2C3, C1C3C2
}
}
原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
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原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
如有侵权,请联系 cloudcommunity@tencent.com 删除。