Data used for packet error has been modified.
[crypto_lab1.git] / src / crypto.rs
1 use std::rand::{ OsRng, Rng };
2 use std::io::IoResult;
3 use std::slice::bytes::copy_memory;
4 use openssl::crypto::hash::SHA256;
5 use openssl::crypto::hmac::HMAC;
6 use openssl::crypto::symm;
7
8 static KEY_A: &'static [u8] = [125, 31, 131, 118, 143, 180, 252, 53, 211, 217, 79, 240, 128, 91, 252, 87, 104, 236, 145, 198, 163, 203, 161, 12, 53, 56, 218, 40, 221, 95, 171, 140];
9 static KEY_C: &'static [u8] = [75, 226, 88, 31, 223, 216, 182, 216, 178, 58, 59, 193, 245, 80, 254, 128, 125, 246, 246, 224, 194, 190, 123, 123, 10, 131, 217, 183, 112, 157, 166, 102];
10
11 pub fn compute_mac(data: &[u8]) -> [u8, ..10] {
12 let mut hmac = HMAC(SHA256, KEY_A);
13 hmac.update(data);
14 let mut result = [0u8, ..10];
15 copy_memory(&mut result, hmac.finalize().slice(0, 10));
16 result
17 }
18
19 pub fn encrypt(plaindata: &[u8], iv: &[u8]) -> Vec<u8> {
20 symm::encrypt(symm::AES_256_CBC, KEY_C, iv.to_vec(), plaindata)
21 }
22
23 pub fn decrypt(cypherdata: &[u8], iv: &[u8]) -> Vec<u8> {
24 symm::decrypt(symm::AES_256_CBC, KEY_C, iv.to_vec(), cypherdata)
25 }
26
27 pub fn generate_key(size_byte: uint) -> IoResult<Vec<u8>> {
28 let mut bytes = Vec:: from_elem(size_byte, 0u8);
29 let mut generator = try!(OsRng::new()); // Uses '/dev/urandom' on Unix-like systems.
30 generator.fill_bytes(bytes.as_mut_slice_());
31 Ok(bytes)
32 }