CryptoKo

This app made in python with kivy framework, works with cryptography library

Features

• Encrypt messages and generate key
• Decrypt messages with key
• Simple and beautiful UI

Fernet (symmetric encryption)¶

Fernet guarantees that a message encrypted using it cannot be manipulated or read without the key. Fernet is an implementation of symmetric (also known as “secret key”) authenticated cryptography.
Fernet also has support for implementing key rotation via MultiFernet.

This app generates a fresh fernet key for each message (each time you press Encrypt button). Keep this some place safe! If you lose it you’ll no longer be able to decrypt messages; if anyone else gains access to it, they’ll be able to decrypt your messages, and they’ll also be able forge arbitrary messages that will be authenticated and decrypted.

Implementation ¶

Fernet is built on top of a number of standard cryptographic primitives. Specifically it uses:

• AES in CBC mode with a 128-bit key for encryption; using PKCS7 padding.
• HMAC using SHA256 for authentication.
• nitialization vectors are generated using os.urandom().

Encrypt

Encrypts data passed. The result of this encryption is known as a “Fernet token” and has strong privacy and authenticity guarantes. you will receive both the encrypted plaintext and decryption key as the result copied to clipboard

Encrypted Message: 
gAAAAABjyikCuDrKLCNF3f-W8mYjrQYiBNU5ggIoDutXMP6yikWewN3XIq0NGhE5OkR30hpSpnR21ZucRcGQ7-2yQZC4JaFhrA==

Decryption Key: 
fKf3iOMfUQ-UrIddfvFPrEDWEGPQDnUzS4wKIXrzZYQ=

Decrypt

If successfully decrypted you will receive the original plaintext as the result copied to clipboard, otherwise an exception will be raised

Decrypted Message: 
hi

Note

So... I'm new in Kivy and trying to learn more and more. in future, I may add more features.

• resize main kivy window when soft keyboard appears
• encrypt_at_time
• decrypt_at_time
• extract_timestamp
• more screens

Hope you enjoy it.

Installation

• clone

git clone https://github.com/Kourva/CryptoKo && cd CryptoKo

• requirements

pip install kivy cryptography

• run

python3 main.py

use google colab and convert your kivy app to apk easily.

Preview