Vb.net 如何解密MD5哈希

我已使用以下函数加密我的密码：

HashPasswordForStoringInConfigFile(Password, "MD5")

现在我想再次解密密码

---

注意我在网格视图中显示加密的密码，我想在特定行进入编辑模式时对其进行解密。

您可以使用类似的加密和解密功能对文本进行加密和解密，您还可以根据需要显示解密文本 下面是函数

Public Function Encrypt(ByVal plainText As String) As String

    Dim passPhrase As String = "yourPassPhrase"
    Dim saltValue As String = "mySaltValue"
    Dim hashAlgorithm As String = "MD5"

    Dim passwordIterations As Integer = 2
    Dim initVector As String = "@1B2c3D4e5F6g7H8"
    Dim keySize As Integer = 256

    Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes(initVector)
    Dim saltValueBytes As Byte() = Encoding.ASCII.GetBytes(saltValue)

    Dim plainTextBytes As Byte() = Encoding.UTF8.GetBytes(plainText)


    Dim password As New PasswordDeriveBytes(passPhrase, saltValueBytes, hashAlgorithm, passwordIterations)

    Dim keyBytes As Byte() = password.GetBytes(keySize \ 8)
    Dim symmetricKey As New RijndaelManaged()

    symmetricKey.Mode = CipherMode.CBC

    Dim encryptor As ICryptoTransform = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes)

    Dim memoryStream As New MemoryStream()
    Dim cryptoStream As New CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write)

    cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length)
    cryptoStream.FlushFinalBlock()
    Dim cipherTextBytes As Byte() = memoryStream.ToArray()
    memoryStream.Close()
    cryptoStream.Close()
    Dim cipherText As String = Convert.ToBase64String(cipherTextBytes)
    Return cipherText
End Function

对于解密，请使用此

Public Function Decrypt(ByVal cipherText As String) As String
    Dim passPhrase As String = "yourPassPhrase"
    Dim saltValue As String = "mySaltValue"
    Dim hashAlgorithm As String = "MD5"

    Dim passwordIterations As Integer = 2
    Dim initVector As String = "@1B2c3D4e5F6g7H8"
    Dim keySize As Integer = 256
    ' Convert strings defining encryption key characteristics into byte
    ' arrays. Let us assume that strings only contain ASCII codes.
    ' If strings include Unicode characters, use Unicode, UTF7, or UTF8
    ' encoding.
    Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes(initVector)
    Dim saltValueBytes As Byte() = Encoding.ASCII.GetBytes(saltValue)

    ' Convert our ciphertext into a byte array.
    Dim cipherTextBytes As Byte() = Convert.FromBase64String(cipherText)

    ' First, we must create a password, from which the key will be 
    ' derived. This password will be generated from the specified 
    ' passphrase and salt value. The password will be created using
    ' the specified hash algorithm. Password creation can be done in
    ' several iterations.
    Dim password As New PasswordDeriveBytes(passPhrase, saltValueBytes, hashAlgorithm, passwordIterations)

    ' Use the password to generate pseudo-random bytes for the encryption
    ' key. Specify the size of the key in bytes (instead of bits).
    Dim keyBytes As Byte() = password.GetBytes(keySize \ 8)

    ' Create uninitialized Rijndael encryption object.
    Dim symmetricKey As New RijndaelManaged()

    ' It is reasonable to set encryption mode to Cipher Block Chaining
    ' (CBC). Use default options for other symmetric key parameters.
    symmetricKey.Mode = CipherMode.CBC

    ' Generate decryptor from the existing key bytes and initialization 
    ' vector. Key size will be defined based on the number of the key 
    ' bytes.
    Dim decryptor As ICryptoTransform = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes)

    ' Define memory stream which will be used to hold encrypted data.
    Dim memoryStream As New MemoryStream(cipherTextBytes)

    ' Define cryptographic stream (always use Read mode for encryption).
    Dim cryptoStream As New CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read)

    ' Since at this point we don't know what the size of decrypted data
    ' will be, allocate the buffer long enough to hold ciphertext;
    ' plaintext is never longer than ciphertext.
    Dim plainTextBytes As Byte() = New Byte(cipherTextBytes.Length - 1) {}

    ' Start decrypting.
    Dim decryptedByteCount As Integer = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length)

    ' Close both streams.
    memoryStream.Close()
    cryptoStream.Close()

    ' Convert decrypted data into a string. 
    ' Let us assume that the original plaintext string was UTF8-encoded.
    Dim plainText As String = Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount)

    ' Return decrypted string.   
    Return plainText
End Function

---

并调用将得到结果的函数。

您可以像这样使用加密和解密函数对文本进行加密和解密，并且还可以根据需要显示解密文本 下面是函数

Public Function Encrypt(ByVal plainText As String) As String

    Dim passPhrase As String = "yourPassPhrase"
    Dim saltValue As String = "mySaltValue"
    Dim hashAlgorithm As String = "MD5"

    Dim passwordIterations As Integer = 2
    Dim initVector As String = "@1B2c3D4e5F6g7H8"
    Dim keySize As Integer = 256

    Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes(initVector)
    Dim saltValueBytes As Byte() = Encoding.ASCII.GetBytes(saltValue)

    Dim plainTextBytes As Byte() = Encoding.UTF8.GetBytes(plainText)


    Dim password As New PasswordDeriveBytes(passPhrase, saltValueBytes, hashAlgorithm, passwordIterations)

    Dim keyBytes As Byte() = password.GetBytes(keySize \ 8)
    Dim symmetricKey As New RijndaelManaged()

    symmetricKey.Mode = CipherMode.CBC

    Dim encryptor As ICryptoTransform = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes)

    Dim memoryStream As New MemoryStream()
    Dim cryptoStream As New CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write)

    cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length)
    cryptoStream.FlushFinalBlock()
    Dim cipherTextBytes As Byte() = memoryStream.ToArray()
    memoryStream.Close()
    cryptoStream.Close()
    Dim cipherText As String = Convert.ToBase64String(cipherTextBytes)
    Return cipherText
End Function

对于解密，请使用此

Public Function Decrypt(ByVal cipherText As String) As String
    Dim passPhrase As String = "yourPassPhrase"
    Dim saltValue As String = "mySaltValue"
    Dim hashAlgorithm As String = "MD5"

    Dim passwordIterations As Integer = 2
    Dim initVector As String = "@1B2c3D4e5F6g7H8"
    Dim keySize As Integer = 256
    ' Convert strings defining encryption key characteristics into byte
    ' arrays. Let us assume that strings only contain ASCII codes.
    ' If strings include Unicode characters, use Unicode, UTF7, or UTF8
    ' encoding.
    Dim initVectorBytes As Byte() = Encoding.ASCII.GetBytes(initVector)
    Dim saltValueBytes As Byte() = Encoding.ASCII.GetBytes(saltValue)

    ' Convert our ciphertext into a byte array.
    Dim cipherTextBytes As Byte() = Convert.FromBase64String(cipherText)

    ' First, we must create a password, from which the key will be 
    ' derived. This password will be generated from the specified 
    ' passphrase and salt value. The password will be created using
    ' the specified hash algorithm. Password creation can be done in
    ' several iterations.
    Dim password As New PasswordDeriveBytes(passPhrase, saltValueBytes, hashAlgorithm, passwordIterations)

    ' Use the password to generate pseudo-random bytes for the encryption
    ' key. Specify the size of the key in bytes (instead of bits).
    Dim keyBytes As Byte() = password.GetBytes(keySize \ 8)

    ' Create uninitialized Rijndael encryption object.
    Dim symmetricKey As New RijndaelManaged()

    ' It is reasonable to set encryption mode to Cipher Block Chaining
    ' (CBC). Use default options for other symmetric key parameters.
    symmetricKey.Mode = CipherMode.CBC

    ' Generate decryptor from the existing key bytes and initialization 
    ' vector. Key size will be defined based on the number of the key 
    ' bytes.
    Dim decryptor As ICryptoTransform = symmetricKey.CreateDecryptor(keyBytes, initVectorBytes)

    ' Define memory stream which will be used to hold encrypted data.
    Dim memoryStream As New MemoryStream(cipherTextBytes)

    ' Define cryptographic stream (always use Read mode for encryption).
    Dim cryptoStream As New CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read)

    ' Since at this point we don't know what the size of decrypted data
    ' will be, allocate the buffer long enough to hold ciphertext;
    ' plaintext is never longer than ciphertext.
    Dim plainTextBytes As Byte() = New Byte(cipherTextBytes.Length - 1) {}

    ' Start decrypting.
    Dim decryptedByteCount As Integer = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length)

    ' Close both streams.
    memoryStream.Close()
    cryptoStream.Close()

    ' Convert decrypted data into a string. 
    ' Let us assume that the original plaintext string was UTF8-encoded.
    Dim plainText As String = Encoding.UTF8.GetString(plainTextBytes, 0, decryptedByteCount)

    ' Return decrypted string.   
    Return plainText
End Function

然后调用函数，您将得到结果。

简单的答案是“您不能”

散列的思想是从真实密码生成一个“安全”代码，该代码可以明文存储；在数据库（或文本文件）中，其他用户可能会以某种方式看到它

当有人尝试登录时，您的系统将从新登录中计算另一个哈希值，然后与现有数据库中的现有哈希值进行比较，如果哈希值匹配，则您知道这是正确的密码，然后您可以允许他们登录，否则，就不是相同的密码/登录失败

无法反转哈希的原因是，通过执行以下步骤计算哈希：

1） 将密码放入某些算法中，以： 2） 生成一个非常大的字符串，然后： 3） 切掉那根绳子，然后： 4） 把它的一部分作为你的“杂烩”

因此，你看，即使你是解码方面的超人，能够找出算法，知道散列码，并设法将其还原为原始形式，那么你仍然会丢失部分密码，因此不成功

这就是为什么散列是安全的

我希望这能解释它。

简单的答案是“你不能”

散列的思想是从真实密码生成一个“安全”代码，该代码可以明文存储；在数据库（或文本文件）中，其他用户可能会以某种方式看到它

当有人尝试登录时，您的系统将从新登录中计算另一个哈希值，然后与现有数据库中的现有哈希值进行比较，如果哈希值匹配，则您知道这是正确的密码，然后您可以允许他们登录，否则，就不是相同的密码/登录失败

无法反转哈希的原因是，通过执行以下步骤计算哈希：

1） 将密码放入某些算法中，以： 2） 生成一个非常大的字符串，然后： 3） 切掉那根绳子，然后： 4） 把它的一部分作为你的“杂烩”

因此，你看，即使你是解码方面的超人，能够找出算法，知道散列码，并设法将其还原为原始形式，那么你仍然会丢失部分密码，因此不成功

这就是为什么散列是安全的

---

我希望这能解释这一点。

目前还不可能将密码的散列放入算法中，然后以明文形式返回密码，因为散列是单向的。但人们所做的是生成散列并将其存储在一个大表中，这样当您输入一个特定的散列时，它会检查表中与散列匹配的密码，并将该密码返回给您。这样做的站点示例如下。现代密码存储系统通过使用盐析算法来应对这种情况，这样，当您在注册期间将同一密码输入密码框时，会生成不同的哈希值。

由于哈希是单向的，所以现在还不可能将密码的哈希值放入算法并以明文形式返回密码。但人们所做的是生成散列并将其存储在一个大表中，这样当您输入一个特定的散列时，它会检查表中与散列匹配的密码，并将该密码返回给您。这样做的站点示例如下。现代密码存储系统通过使用一种盐析算法来应对这种情况，这样，当您在注册期间向密码框中输入相同的密码时，将生成不同的哈希。

您无法解密哈希。。。而且你无论如何也不能解密密码。原因很简单：哈希将字符串映射到某个数字/id，但可能会发生冲突-不同的输入具有相同的输出-因此函数不是内射的。如果这将是一个真正的产品，考虑到安全性，请获得一些专家帮助-我已经可以告诉您，您的产品将根本不安全！（例如：在散列之前，你应该在你的密码中添加盐，MD5是一种）@shafay用于加密你的密码我会说没有用或类似的话。。。但是真的：不要自己实现加密/安全性（只有这么多人不适用此规则-我除外）-（从我上面链接的讨论中很容易找到此链接-但就这样吧）好的。。谢谢大家！您无法解密哈希。。。而且你无论如何也不能解密密码。原因很简单：哈希将字符串映射到某个数字/id，但可能会发生冲突-不同的输入具有相同的输出-因此函数不是内射的。如果这将是一个真正的产品，考虑到安全性，请获得一些专家帮助-我已经可以告诉您，您的产品将根本不安全！（例如：在散列之前，你应该在你的密码中添加盐，MD5是一种）@shafay用于加密你的密码我会说没有用或类似的话。。。但是真的：不要自己实现加密/安全性（只有这么多人不适用此规则-我除外）-（从我上面链接的讨论中很容易找到此链接-但就这样吧）好的。。谢谢大家！

PasswordDeriveBytes

是i