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extern crate matasano;
extern crate rand;
use rand::Rng;
mod util;
#[test]
fn problem_25 () {
let key = util::random_aes_128_key();
let nonce: u64 = rand::thread_rng().gen();
let plaintext = util::read("data/25.txt");
let ciphertext = matasano::aes_128_ctr(&plaintext[..], &key[..], nonce);
let edit = |ciphertext: &[u8], offset: usize, newtext: &[u8]| {
let block_start_number = offset / 16;
let block_start = block_start_number * 16;
let block_end_number = (offset + newtext.len() - 1) / 16;
let block_end = std::cmp::min(
(block_end_number + 1) * 16,
ciphertext.len()
);
let mut plaintext = matasano::aes_128_ctr_with_counter(
&ciphertext[block_start..block_end],
&key[..],
nonce,
(offset / 16) as u64
);
for i in 0..newtext.len() {
plaintext[offset - block_start + i] = newtext[i];
}
let new_ciphertext = matasano::aes_128_ctr_with_counter(
&plaintext[..],
&key[..],
nonce,
(offset / 16) as u64
);
return ciphertext
.iter()
.take(block_start)
.chain(new_ciphertext.iter())
.chain(ciphertext.iter().skip(block_end))
.map(|x| *x)
.collect();
};
let got = matasano::crack_aes_128_ctr_random_access(&ciphertext[..], edit);
assert_eq!(&got[..], &plaintext[..]);
}
#[test]
fn problem_26 () {
let key = util::random_aes_128_key();
let nonce = rand::thread_rng().gen();
let prefix = "comment1=cooking%20MCs;userdata=";
let suffix = ";comment2=%20like%20a%20pound%20of%20bacon";
let admin = ";admin=true;";
let escape = |input: &str| {
input.replace("%", "%25").replace(";", "%3B").replace("=", "%3D")
};
let encode = |input: &str| -> Vec<u8> {
let plaintext: Vec<u8> = prefix
.as_bytes()
.iter()
.chain(escape(input).as_bytes().iter())
.chain(suffix.as_bytes().iter())
.map(|x| *x)
.collect();
return matasano::aes_128_ctr(&plaintext[..], &key[..], nonce);
};
let verify = |ciphertext: &[u8]| -> bool {
let plaintext = matasano::aes_128_ctr(ciphertext, &key[..], nonce);
return (0..(plaintext.len() - admin.len())).any(|i| {
plaintext
.iter()
.skip(i)
.zip(admin.as_bytes().iter())
.all(|(&c1, &c2)| c1 == c2)
});
};
let ciphertext = matasano::crack_ctr_bitflipping(&encode);
assert!(verify(&ciphertext[..]));
}
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