华为快应用中的 密码算法 在ASP.NET中的实现RSA加密解密_rsa/none/oaepwithsha-256andmgf1padding

华为快应用将会成为未来5G的重要APP模式，也可能是鸿蒙系统HMS的重要软件提组成。 快应用目前可以兼容手机、平板、汽车等移动载体，不久的未来还会支持手表等更多移动端。 因而现在的程序猿人们有时间可以看起来未来的快应用开发平台了。 

言归正传， 华为快应用目前提供了基于RSA Cipher的非对称加密解密API安全接口，可用于与服务端的安全加密数据交互。但是，ASP.Net没有原生的RSA Cipher 组件对应华为的API安全加密解密，因而笔者经过了一周时间的苦心研究，终于找到了解决方案，在此和各位伙伴分享。 希望大家可以在此内容上节约一些时间。

解决方案是使用基于第三方组件 BouncyCastle.Crypto.dll 对RSA Cipher数据进行解密或明文进行加密。

代码如下：

 
Imports Org.BouncyCastle.Asn1.Pkcs
Imports Org.BouncyCastle.Asn1.X509
Imports Org.BouncyCastle.Crypto.Generators
Imports Org.BouncyCastle.Crypto.Parameters
Imports Org.BouncyCastle.Math
Imports Org.BouncyCastle.Pkcs
Imports Org.BouncyCastle.Security
Imports Org.BouncyCastle.Crypto.Engines
Imports Org.BouncyCastle.X509
Imports Org.BouncyCastle.Crypto
Imports Org.BouncyCastle.Asn1
Imports Org.BouncyCastle.Crypto.Encodings
 
 
Public Class RSACipher
 
    Public Sub New(Optional ByVal _Transformation As String = "")
        If _Transformation <> "" Then Transformation = _Transformation
    End Sub
 
 
    ''' <summary>
    ''' KEY 结构体
    ''' </summary>
    Public Structure RSAKEY
        ''' <summary>
        ''' 公钥
        ''' </summary>
        Public Property PublicKey() As String
        ''' <summary>
        ''' 私钥
        ''' </summary>
        Public Property PrivateKey() As String
    End Structure
    Public Transformation As String = "RSA/None/OAEPWithSHA256AndMGF1Padding"
    Public Function GetKey() As RSAKEY
        'RSA密钥对的构造器  
        Dim keyGenerator As New RsaKeyPairGenerator()
 
        'RSA密钥构造器的参数  
        Dim param As New RsaKeyGenerationParameters(Org.BouncyCastle.Math.BigInteger.ValueOf(3), New Org.BouncyCastle.Security.SecureRandom(), 1024, 25) '密钥长度
        '用参数初始化密钥构造器  
        keyGenerator.Init(param)
        '产生密钥对  
        Dim keyPair As AsymmetricCipherKeyPair = keyGenerator.GenerateKeyPair()
        '获取公钥和密钥  
        Dim publicKey As AsymmetricKeyParameter = keyPair.Public
        Dim privateKey As AsymmetricKeyParameter = keyPair.Private
        Dim subjectPublicKeyInfo As SubjectPublicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(publicKey)
        Dim privateKeyInfo As PrivateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKey)
        Dim asn1ObjectPublic As Asn1Object = subjectPublicKeyInfo.ToAsn1Object()
        Dim publicInfoByte() As Byte = asn1ObjectPublic.GetEncoded("UTF-8")
        Dim asn1ObjectPrivate As Asn1Object = privateKeyInfo.ToAsn1Object()
        Dim privateInfoByte() As Byte = asn1ObjectPrivate.GetEncoded("UTF-8")
        Dim item As New RSAKEY() With {.PublicKey = Convert.ToBase64String(publicInfoByte), .PrivateKey = Convert.ToBase64String(privateInfoByte)}
        Return item
    End Function
    Private Function GetPublicKeyParameter(ByVal s As String) As AsymmetricKeyParameter
        s = s.Replace(vbCr, "").Replace(vbLf, "").Replace(" ", "")
        Dim publicInfoByte() As Byte = Convert.FromBase64String(s)
        Dim pubKeyObj As Asn1Object = Asn1Object.FromByteArray(publicInfoByte) '这里也可以从流中读取，从本地导入
        Dim pubKey As AsymmetricKeyParameter = PublicKeyFactory.CreateKey(publicInfoByte)
        Return pubKey
    End Function
 
    Private Function GetPrivateKeyParameter(ByVal s As String) As AsymmetricKeyParameter
        s = s.Replace(vbCr, "").Replace(vbLf, "").Replace(" ", "")
        Dim privateInfoByte() As Byte = Convert.FromBase64String(s)
        ' Asn1Object priKeyObj = Asn1Object.FromByteArray(privateInfoByte);//这里也可以从流中读取，从本地导入   
        ' PrivateKeyInfo privateKeyInfo = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKey);
        Dim priKey As AsymmetricKeyParameter = PrivateKeyFactory.CreateKey(privateInfoByte)
 
        Return priKey
    End Function
 
    '加密 
    Public Function EncryptByPublicKey(ByVal s As String, ByVal key As String) As String
        '非对称加密算法，加解密用  
        Dim engine As IBufferedCipher = CipherUtilities.GetCipher(Transformation)
 
 
        '加密  
        Try
            engine.Init(True, GetPublicKeyParameter(key))
            Dim byteData() As Byte = System.Text.Encoding.UTF8.GetBytes(s)
            Dim ResultData = engine.DoFinal(byteData)
            Return Convert.ToBase64String(ResultData)
            'Console.WriteLine("密文（base64编码）:" + Convert.ToBase64String(testData) + Environment.NewLine);
        Catch ex As Exception
            Return ex.Message
 
        End Try
    End Function
 
    '解密
    Public Function DecryptByPrivateKey(ByVal s As String, ByVal key As String) As String
        s = s.Replace(vbCr, "").Replace(vbLf, "").Replace(" ", "")
        '非对称加密算法，加解密用  
        'Dim engine As IAsymmetricBlockCipher = New Pkcs1Encoding(New RsaEngine( ))
        Dim engine As IBufferedCipher = CipherUtilities.GetCipher(Transformation)
        '解密  
 
        Try
            engine.Init(False, GetPrivateKeyParameter(key))
            Dim byteData() As Byte = Convert.FromBase64String(s)
            Dim ResultData = engine.DoFinal(byteData)
            Return System.Text.Encoding.UTF8.GetString(ResultData)
 
        Catch ex As Exception
            Return ex.Message
 
        End Try
    End Function
End Class

这里需要特别主义的是 Public Transformation As String = "RSA/None/OAEPWithSHA256AndMGF1Padding" 必须和华为官方文档中的内容一致，否则无法正确解密。

此类需要使用到的插件： bouncycastle.crypto.dll  可以在以下官网下载，

http://www.bouncycastle.org/

希望对各位快应用开发者有帮助。