Encrypt, decrypt and generate a key in C# using AES256.
encryption.cs
#regionEncryption |
/// <summary> |
/// Generate a private key |
/// From : www.chapleau.info/blog/2011/01/06/usingsimplestringkeywithaes256encryptioninc.html |
/// </summary> |
privatestaticstringGenerateKey(intiKeySize) |
{ |
RijndaelManagedaesEncryption=newRijndaelManaged(); |
aesEncryption.KeySize=iKeySize; |
aesEncryption.BlockSize=128; |
aesEncryption.Mode=CipherMode.CBC; |
aesEncryption.Padding=PaddingMode.PKCS7; |
aesEncryption.GenerateIV(); |
stringivStr=Convert.ToBase64String(aesEncryption.IV); |
aesEncryption.GenerateKey(); |
stringkeyStr=Convert.ToBase64String(aesEncryption.Key); |
stringcompleteKey=ivStr+','+keyStr; |
returnConvert.ToBase64String(ASCIIEncoding.UTF8.GetBytes(completeKey)); |
} |
/// <summary> |
/// Encrypt |
/// From : www.chapleau.info/blog/2011/01/06/usingsimplestringkeywithaes256encryptioninc.html |
/// </summary> |
privatestaticstringEncrypt(stringiPlainStr, stringiCompleteEncodedKey, intiKeySize) |
{ |
RijndaelManagedaesEncryption=newRijndaelManaged(); |
aesEncryption.KeySize=iKeySize; |
aesEncryption.BlockSize=128; |
aesEncryption.Mode=CipherMode.CBC; |
aesEncryption.Padding=PaddingMode.PKCS7; |
aesEncryption.IV=Convert.FromBase64String(ASCIIEncoding.UTF8.GetString(Convert.FromBase64String(iCompleteEncodedKey)).Split(',')[0]); |
aesEncryption.Key=Convert.FromBase64String(ASCIIEncoding.UTF8.GetString(Convert.FromBase64String(iCompleteEncodedKey)).Split(',')[1]); |
byte[] plainText=ASCIIEncoding.UTF8.GetBytes(iPlainStr); |
ICryptoTransformcrypto=aesEncryption.CreateEncryptor(); |
byte[] cipherText=crypto.TransformFinalBlock(plainText, 0, plainText.Length); |
returnConvert.ToBase64String(cipherText); |
} |
/// <summary> |
/// Decrypt |
/// From : www.chapleau.info/blog/2011/01/06/usingsimplestringkeywithaes256encryptioninc.html |
/// </summary> |
privatestaticstringDecrypt(stringiEncryptedText, stringiCompleteEncodedKey, intiKeySize) |
{ |
RijndaelManagedaesEncryption=newRijndaelManaged(); |
aesEncryption.KeySize=iKeySize; |
aesEncryption.BlockSize=128; |
aesEncryption.Mode=CipherMode.CBC; |
aesEncryption.Padding=PaddingMode.PKCS7; |
aesEncryption.IV=Convert.FromBase64String(ASCIIEncoding.UTF8.GetString(Convert.FromBase64String(iCompleteEncodedKey)).Split(',')[0]); |
aesEncryption.Key=Convert.FromBase64String(ASCIIEncoding.UTF8.GetString(Convert.FromBase64String(iCompleteEncodedKey)).Split(',')[1]); |
ICryptoTransformdecrypto=aesEncryption.CreateDecryptor(); |
byte[] encryptedBytes=Convert.FromBase64CharArray(iEncryptedText.ToCharArray(), 0, iEncryptedText.Length); |
returnASCIIEncoding.UTF8.GetString(decrypto.TransformFinalBlock(encryptedBytes, 0, encryptedBytes.Length)); |
} |
#endregion |
I am trying to create a function I can put a string key (I have another algorithm to generate the key) into and a message string. The function should encrypt and decrypt the text using the aes256-cbc from OpenSSL library. Nov 16, 2016 Encrypt Strings with Passwords - AES 256 & SHA256. Rate this: 4.95 (8 votes). I create a hash with SHA2 (256 bit) from the password, this hash is the key and IV in the AES Encryption. I was looking for a quick intro to AES 256 encryption to get me started and this was a nice article that helped me. 256-bit encryption is a data/file encryption technique that uses a 256-bit key to encrypt and decrypt data or files. It is one of the most secure encryption methods after 128- and 192-bit encryption, and is used in most modern encryption algorithms, protocols and technologies including AES and SSL.
commented Jun 6, 2014
hi fairly new to the cryptography.. when im implementing the above code im getting a error while decrypting. 'Padding is invalid and cannot be removed.' please suggest a resolution thanks and regards |
commented Oct 9, 2017 • edited
edited
How-to save -safely- the private key ? Windows registry ? in disk ? I use ASP.NET applications. Test your code |
Sign up for freeto join this conversation on GitHub. Already have an account? Sign in to comment
Chilkat • HOME • Android™ • Classic ASP • C • C++ • C# • Mono C# • .NET Core C# • C# UWP/WinRT • DataFlex • Delphi ActiveX • Delphi DLL • Visual FoxPro • Java • Lianja • MFC • Objective-C • Perl • PHP ActiveX • PHP Extension • PowerBuilder • PowerShell • PureBasic • CkPython • Chilkat2-Python • Ruby • SQL Server • Swift 2 • Swift 3/4 • Tcl • Unicode C • Unicode C++ • Visual Basic 6.0 • VB.NET • VB.NET UWP/WinRT • VBScript • Xojo Plugin • Node.js • Excel • Go
| Discusses symmetric encryption key generation techniques for block encryption algorithms such as AES, Blowfish, and Twofish, or for other algorithms such as ChaCha20.
|
C Programming Generate A 256 Bit Encryption Keyboard
512 Bit Encryption
Product key generator office. © 2000-2020 Chilkat Software, Inc. All Rights Reserved.