DES is a project mainly written in C++ and C, it's free.
Applied Cryptography HW #5
Aaveg Mittal
[email protected]
Homework5. Design . There are total 4 files 3 source file(main.cc, keyschedule.cc, tablecheck.cc ) and 1 header file(main.h).
main.cc:
. mainly contains the general code, such as userinput parsing & then calling the appropriote function.
keyschedule.cc
.unsigned char readBit(unsigned char *, int)
A very handy function, which reads a bit at a particular location in a char array.
.void writeBit(unsigned char *, int, unsigned char)
Another handy function to write the bit at a particular location in a char array specified by the third argument
.void KeySchedule
To produce 16 subkeys by iterating 16 rounds
.void Crypt
Encrypts/decrypts 8 bytes of data, using the set of subkeys specified in the argument
.void encrypt
Encrypt the input by calling Crypt function over blocks of 8 bytes of data
.void decrypt
Decrypts the cypher text by calling the Crypt function using the inverse of the sub keys
.void encrypt3
Performs tripple DES following the pattern as Encryption-Decryption-Encryption
.void decrypt3
Performs tripple DES following the pattern as Decryption-Encyption-Decryption