🔐 Encrypt-Decrypt-application

Write an application that uses C# to encrypt and decrypt a file.

• MVVM pattern
• Use AES to encrypt file p into file C and generate private key Ks
• Use RSA to generate Kprivate and Kpublic and encrypt Ks by Kpublic.
• Hash Kprivate into Ks and store hash value
• Output Kprivate and user can use it to decrypt file.

  🤝 Members

  Hoang Huu Minh An - 20127102

Tran Tien Hoang - 20127424

🏗️ Build Mode

• Using System.Security.Cryptography

• Class EncryptionAlgorithm

  • Generate Kprivate and Kpublic by RSA algorithm.
  • Length of keys: 64, 256, 1024, 2048 bits
  • Calculate hash value of string by SHA-1, SHA-256
  • Generate Ks by AES algorithm.

    🖥️ GUI

• Encrypt

• Decrypt

🔎 How to use

• Allows users to encrypt a file in steps

  • The user selects the file to encrypt.
  • The system generates secret key Ks and encrypts file P into file C using AES algorithm.
  • The system generates the Private and Public key pairs of the RSA algorithm and encrypts the key Ks with the Kpublic key, the output is the string Kx.
  • The system saves the Kx string with the SHA-1 hash value of Kprivate (called HKprivate). Can be exported to a C.metadata file, where C is the name of the above C file, the file structure is optional (XML, JSON, Plain text...).
  • Export Private Key.

• Allows users to decrypt a file in steps

  • The user selects the file to decrypt.
  • The user kprivate
  • The system checks if Kprivate's SHA-1 hash value is the same as HKprivate's
  • Decrypt the string Kx to get Ks using Kprivate
  • Use Ks to decode file C into file P.

Link Demo