#![no_std]
#![doc(
html_logo_url = "https://raw.githubusercontent.com/RustCrypto/media/6ee8e381/logo.svg",
html_favicon_url = "https://raw.githubusercontent.com/RustCrypto/media/6ee8e381/logo.svg"
)]
#![forbid(unsafe_code)]
#![warn(rust_2018_idioms)]
#![allow(clippy::many_single_char_names)]
pub use digest::{self, Digest};
use core::{convert::TryInto, fmt};
#[cfg(feature = "oid")]
use digest::const_oid::{AssociatedOid, ObjectIdentifier};
use digest::{
block_buffer::Eager,
core_api::{
AlgorithmName, Block, BlockSizeUser, Buffer, BufferKindUser, CoreWrapper, FixedOutputCore,
OutputSizeUser, Reset, UpdateCore,
},
typenum::{Unsigned, U16, U64},
HashMarker, Output,
};
#[derive(Clone)]
pub struct Md4Core {
block_len: u64,
state: [u32; 4],
}
impl HashMarker for Md4Core {}
impl BlockSizeUser for Md4Core {
type BlockSize = U64;
}
impl BufferKindUser for Md4Core {
type BufferKind = Eager;
}
impl OutputSizeUser for Md4Core {
type OutputSize = U16;
}
impl UpdateCore for Md4Core {
#[inline]
fn update_blocks(&mut self, blocks: &[Block<Self>]) {
self.block_len = self.block_len.wrapping_add(blocks.len() as u64);
for block in blocks {
compress(&mut self.state, block);
}
}
}
impl FixedOutputCore for Md4Core {
#[inline]
fn finalize_fixed_core(&mut self, buffer: &mut Buffer<Self>, out: &mut Output<Self>) {
let bit_len = self
.block_len
.wrapping_mul(Self::BlockSize::U64)
.wrapping_add(buffer.get_pos() as u64)
.wrapping_mul(8);
let mut state = self.state;
buffer.len64_padding_le(bit_len, |block| compress(&mut state, block));
for (chunk, v) in out.chunks_exact_mut(4).zip(state.iter()) {
chunk.copy_from_slice(&v.to_le_bytes());
}
}
}
impl Default for Md4Core {
#[inline]
fn default() -> Self {
let state = [0x6745_2301, 0xEFCD_AB89, 0x98BA_DCFE, 0x1032_5476];
Self {
state,
block_len: 0,
}
}
}
impl Reset for Md4Core {
#[inline]
fn reset(&mut self) {
*self = Default::default();
}
}
impl AlgorithmName for Md4Core {
fn write_alg_name(f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.write_str("Md4")
}
}
impl fmt::Debug for Md4Core {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.write_str("Md4Core { ... }")
}
}
#[cfg(feature = "oid")]
#[cfg_attr(docsrs, doc(cfg(feature = "oid")))]
impl AssociatedOid for Md4Core {
const OID: ObjectIdentifier = ObjectIdentifier::new_unwrap("1.2.840.113549.2.4");
}
pub type Md4 = CoreWrapper<Md4Core>;
fn compress(state: &mut [u32; 4], input: &Block<Md4Core>) {
fn f(x: u32, y: u32, z: u32) -> u32 {
(x & y) | (!x & z)
}
fn g(x: u32, y: u32, z: u32) -> u32 {
(x & y) | (x & z) | (y & z)
}
fn h(x: u32, y: u32, z: u32) -> u32 {
x ^ y ^ z
}
fn op1(a: u32, b: u32, c: u32, d: u32, k: u32, s: u32) -> u32 {
a.wrapping_add(f(b, c, d)).wrapping_add(k).rotate_left(s)
}
fn op2(a: u32, b: u32, c: u32, d: u32, k: u32, s: u32) -> u32 {
a.wrapping_add(g(b, c, d))
.wrapping_add(k)
.wrapping_add(0x5A82_7999)
.rotate_left(s)
}
fn op3(a: u32, b: u32, c: u32, d: u32, k: u32, s: u32) -> u32 {
a.wrapping_add(h(b, c, d))
.wrapping_add(k)
.wrapping_add(0x6ED9_EBA1)
.rotate_left(s)
}
let mut a = state[0];
let mut b = state[1];
let mut c = state[2];
let mut d = state[3];
let mut data = [0u32; 16];
for (o, chunk) in data.iter_mut().zip(input.chunks_exact(4)) {
*o = u32::from_le_bytes(chunk.try_into().unwrap());
}
for &i in &[0, 4, 8, 12] {
a = op1(a, b, c, d, data[i], 3);
d = op1(d, a, b, c, data[i + 1], 7);
c = op1(c, d, a, b, data[i + 2], 11);
b = op1(b, c, d, a, data[i + 3], 19);
}
for i in 0..4 {
a = op2(a, b, c, d, data[i], 3);
d = op2(d, a, b, c, data[i + 4], 5);
c = op2(c, d, a, b, data[i + 8], 9);
b = op2(b, c, d, a, data[i + 12], 13);
}
for &i in &[0, 2, 1, 3] {
a = op3(a, b, c, d, data[i], 3);
d = op3(d, a, b, c, data[i + 8], 9);
c = op3(c, d, a, b, data[i + 4], 11);
b = op3(b, c, d, a, data[i + 12], 15);
}
state[0] = state[0].wrapping_add(a);
state[1] = state[1].wrapping_add(b);
state[2] = state[2].wrapping_add(c);
state[3] = state[3].wrapping_add(d);
}