From d895cc4c9687cd88b10d34b418eac990091fc8bd Mon Sep 17 00:00:00 2001 From: Jesse Luehrs Date: Sun, 5 Apr 2015 23:49:25 -0400 Subject: problem 24, part 1 --- src/crack.rs | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'src/crack.rs') diff --git a/src/crack.rs b/src/crack.rs index 92950c4..b351249 100644 --- a/src/crack.rs +++ b/src/crack.rs @@ -386,6 +386,21 @@ pub fn clone_mersenne_twister_from_output (outputs: &[u32]) -> MersenneTwister { return MersenneTwister::from_seed((state, 0)); } +pub fn recover_16_bit_mt19937_key (ciphertext: &[u8], suffix: &[u8]) -> Option { + for _key in 0..65536u32 { + let key = _key as u16; + let plaintext = ::random::mt19937_stream_cipher( + ciphertext, + key as u32 + ); + if &plaintext[(ciphertext.len() - suffix.len())..] == suffix { + return Some(key); + } + } + + return None; +} + fn crack_single_byte_xor_with_confidence (input: &[u8]) -> (u8, f64) { let mut min_diff = 100.0; let mut best_key = 0; -- cgit v1.2.3-54-g00ecf