/crypto_lib

This library contains the implementation of popular crypto algorithms from scratch using C++

Primary LanguageC++

Crypto library

Library with popular cryptographic algorithms implemented from scratch.

Algorithms implemented

  1. RSA
  2. SHA256
  3. DES
  4. AES
    • AES-128
    • AES-192
    • AES-256

Modes of operation

Implementation for modes of operation involves template metaprogramming. It is a metaprogramming technique in which templates are used by a compiler to generate temporary source code, which is merged by the compiler with the rest of the source code and then compiled.

  1. ECB
  2. CBC
  3. OFB
  4. CFB
  5. CTR

Libraries used

  • OpenSSL
    • generating pseudo-random initialization vector
  • GMP
    • Handling big numbers for RSA algorithm

Compilation

Prerequisites

  1. Installed g++ compiler
  2. Installed OpenSSL library
  3. Installed GMP library

Compile

The project can be compiled using g++ compiler with the following flags:

  1. OpenSSL library

    -lssl -lcrypto

  2. GMP library

    -lgmp -lgmpxx

Output example

DES in CTR mode
Message: 
00112233445566778899aabbccddeeff
Encrypted message: 
7d26047d03b91842f5ae8cf58b3190ca
Decrypted message: 
00112233445566778899aabbccddeeff

Triple DES in OFB mode
Message: 
00112233445566778899aabbccddeeff
Encrypted message: 
ffed24f4243e5bb95473c046a1c8ee8d
Decrypted message: 
00112233445566778899aabbccddeeff

AES-128 in CBC mode
Message: 
00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff
Encrypted message: 
a686e9470065c013d237932b55db169762c9f3c77668db2bdd3600b07370828d
Decrypted message: 
00112233445566778899aabbccddeeff00112233445566778899aabbccddeeff

SHA-256 input str: 
Testing input for the SHA256. Hash will be produced from this string.
is: 
13db07605a6413446825ed281e73ba132c7e951f67df7ea879754b5463eaee36