Skip to content

scrypt: use salsa20 crate to implement Salsa20/8 #60

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 18, 2020
Merged

scrypt: use salsa20 crate to implement Salsa20/8 #60

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
10 changes: 10 additions & 0 deletions Cargo.lock
View file
Open in desktop

Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.

6 changes: 3 additions & 3 deletions scrypt/Cargo.toml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,13 +12,13 @@ edition = "2018"
readme = "README.md"

[dependencies]
base64 = { version = "0.13", default-features = false, features = ["alloc"], optional = true }
hmac = "0.10"
pbkdf2 = { version = "0.6.0-pre", default-features = false, path = "../pbkdf2" }
sha2 = { version = "0.9", default-features = false }

base64 = { version = "0.13", default-features = false, features = ["alloc"], optional = true }
rand_core = { version = "0.5", default-features = false, features = ["getrandom"], optional = true }
rand = { version = "0.7", default-features = false, optional = true }
salsa20 = { version = "0.7.1", default-features = false, features = ["expose-core"] }
sha2 = { version = "0.9", default-features = false }
subtle = { version = "2", default-features = false, optional = true }

[features]
Expand Down
135 changes: 38 additions & 97 deletions scrypt/src/romix.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,102 +1,7 @@
use core::convert::TryInto;

/// The salsa20/8 core function.
#[inline(never)]
fn salsa20_8(input: &[u8], output: &mut [u8]) {
let mut x = [0u32; 16];
assert_eq!(input.len(), 4 * x.len());
for (c, b) in input.chunks_exact(4).zip(x.iter_mut()) {
*b = u32::from_le_bytes(c.try_into().unwrap());
}

macro_rules! run_round (
($($set_idx:expr, $idx_a:expr, $idx_b:expr, $rot:expr);*) => { {
$( x[$set_idx] ^= x[$idx_a].wrapping_add(x[$idx_b]).rotate_left($rot); )*
} }
);

macro_rules! repeat4 (
($block:expr) => {
$block;
$block;
$block;
$block;
}
);

repeat4!({
run_round!(
0x4, 0x0, 0xc, 7;
0x8, 0x4, 0x0, 9;
0xc, 0x8, 0x4, 13;
0x0, 0xc, 0x8, 18;
0x9, 0x5, 0x1, 7;
0xd, 0x9, 0x5, 9;
0x1, 0xd, 0x9, 13;
0x5, 0x1, 0xd, 18;
0xe, 0xa, 0x6, 7;
0x2, 0xe, 0xa, 9;
0x6, 0x2, 0xe, 13;
0xa, 0x6, 0x2, 18;
0x3, 0xf, 0xb, 7;
0x7, 0x3, 0xf, 9;
0xb, 0x7, 0x3, 13;
0xf, 0xb, 0x7, 18;
0x1, 0x0, 0x3, 7;
0x2, 0x1, 0x0, 9;
0x3, 0x2, 0x1, 13;
0x0, 0x3, 0x2, 18;
0x6, 0x5, 0x4, 7;
0x7, 0x6, 0x5, 9;
0x4, 0x7, 0x6, 13;
0x5, 0x4, 0x7, 18;
0xb, 0xa, 0x9, 7;
0x8, 0xb, 0xa, 9;
0x9, 0x8, 0xb, 13;
0xa, 0x9, 0x8, 18;
0xc, 0xf, 0xe, 7;
0xd, 0xc, 0xf, 9;
0xe, 0xd, 0xc, 13;
0xf, 0xe, 0xd, 18
)
});

for (o, (i, b)) in output
.chunks_exact_mut(4)
.zip(input.chunks_exact(4).zip(x.iter()))
{
let a = u32::from_le_bytes((&*i).try_into().unwrap());
let t = b.wrapping_add(a);
o.copy_from_slice(&t.to_le_bytes());
}
}

fn xor(x: &[u8], y: &[u8], output: &mut [u8]) {
for ((out, &x_i), &y_i) in output.iter_mut().zip(x.iter()).zip(y.iter()) {
*out = x_i ^ y_i;
}
}

/// Execute the BlockMix operation
/// input - the input vector. The length must be a multiple of 128.
/// output - the output vector. Must be the same length as input.
fn scrypt_block_mix(input: &[u8], output: &mut [u8]) {
let mut x = [0u8; 64];
x.copy_from_slice(&input[input.len() - 64..]);

let mut t = [0u8; 64];

for (i, chunk) in input.chunks(64).enumerate() {
xor(&x, chunk, &mut t);
salsa20_8(&t, &mut x);
let pos = if i % 2 == 0 {
(i / 2) * 64
} else {
(i / 2) * 64 + input.len() / 2
};
output[pos..pos + 64].copy_from_slice(&x);
}
}
/// The Salsa20/8 core function
type Salsa20_8 = salsa20::Block<salsa20::R8>;

/// Execute the ROMix operation in-place.
/// b - the data to operate on
Expand Down Expand Up @@ -129,3 +34,39 @@ pub(crate) fn scrypt_ro_mix(b: &mut [u8], v: &mut [u8], t: &mut [u8], n: usize)
scrypt_block_mix(t, b);
}
}

/// Execute the BlockMix operation
/// input - the input vector. The length must be a multiple of 128.
/// output - the output vector. Must be the same length as input.
fn scrypt_block_mix(input: &[u8], output: &mut [u8]) {
let mut x = [0u8; 64];
x.copy_from_slice(&input[input.len() - 64..]);

let mut t = [0u8; 64];

for (i, chunk) in input.chunks(64).enumerate() {
xor(&x, chunk, &mut t);

let mut t2 = [0u32; 16];

for (c, b) in t.chunks_exact(4).zip(t2.iter_mut()) {
*b = u32::from_le_bytes(c.try_into().unwrap());
}

Salsa20_8::from(t2).generate(&mut x);

let pos = if i % 2 == 0 {
(i / 2) * 64
} else {
(i / 2) * 64 + input.len() / 2
};

output[pos..pos + 64].copy_from_slice(&x);
}
}

fn xor(x: &[u8], y: &[u8], output: &mut [u8]) {
for ((out, &x_i), &y_i) in output.iter_mut().zip(x.iter()).zip(y.iter()) {
*out = x_i ^ y_i;
}
}