diff --git a/src/impls.rs b/src/impls.rs index 8f5e768..4b1ea0c 100644 --- a/src/impls.rs +++ b/src/impls.rs @@ -7,7 +7,7 @@ use bitcoin_io::impl_write; -use crate::{ripemd160, sha1, sha256, sha512, siphash24, HashEngine, HmacEngine}; +use crate::{ripemd160, sha1, sha256, sha256t, sha512, siphash24, HashEngine, HmacEngine}; impl_write!( sha1::HashEngine, @@ -78,6 +78,16 @@ impl std::io::Write for HmacEngine { fn flush(&mut self) -> std::io::Result<()> { Ok(()) } } +impl_write!( + sha256t::HashEngine, + |us: &mut sha256t::HashEngine, buf| { + us.input(buf); + Ok(buf.len()) + }, + |_us| { Ok(()) }, + T: crate::sha256t::Tag +); + #[cfg(test)] mod tests { use bitcoin_io::Write; diff --git a/src/sha256t.rs b/src/sha256t.rs index f790421..8b9859c 100644 --- a/src/sha256t.rs +++ b/src/sha256t.rs @@ -7,12 +7,45 @@ use core::marker::PhantomData; use crate::{sha256, HashEngine as _}; -type HashEngine = sha256::HashEngine; +/// Engine to compute tagged SHA-256 hash function. +#[derive(Clone)] +pub struct HashEngine(sha256::HashEngine, PhantomData); + +impl Default for HashEngine { + fn default() -> Self { ::engine() } +} + +impl crate::HashEngine for HashEngine { + type Digest = [u8; 32]; + type Midstate = sha256::Midstate; + const BLOCK_SIZE: usize = sha256::BLOCK_SIZE; + + #[inline] + fn new() -> Self { ::engine() } + + #[inline] + fn input(&mut self, data: &[u8]) { self.0.input(data) } + + #[inline] + fn n_bytes_hashed(&self) -> usize { self.0.n_bytes_hashed() } + + #[inline] + fn finalize(self) -> Self::Digest { self.0.finalize() } + + #[inline] + fn midstate(&self) -> Self::Midstate { self.0.midstate() } + + #[inline] + fn from_midstate(midstate: sha256::Midstate, length: usize) -> HashEngine { + let inner = sha256::HashEngine::from_midstate(midstate, length); + Self(inner, PhantomData) + } +} /// Trait representing a tag that can be used as a context for SHA256t hashes. -pub trait Tag { +pub trait Tag: Clone { /// Returns a hash engine that is pre-tagged and is ready to be used for the data. - fn engine() -> sha256::HashEngine; + fn engine() -> HashEngine; } /// Output of the SHA256t hash function. @@ -36,12 +69,12 @@ impl Hash { } /// Returns a hash engine that is ready to be used for data. - pub fn engine() -> HashEngine { ::engine() } + pub fn engine() -> HashEngine { ::engine() } /// Creates a `Hash` from an `engine`. /// /// This is equivalent to calling `Hash::from_byte_array(engine.finalize())`. - pub fn from_engine(engine: HashEngine) -> Self { + pub fn from_engine(engine: HashEngine) -> Self { let digest = engine.finalize(); Self(digest, PhantomData) } @@ -130,7 +163,8 @@ crate::internal_macros::hash_trait_impls!(256, T: Tag); #[cfg(test)] mod tests { - use crate::{sha256, sha256t}; + use super::*; + use crate::sha256; const TEST_MIDSTATE: [u8; 32] = [ 156, 224, 228, 230, 124, 17, 108, 57, 56, 179, 202, 242, 195, 15, 80, 137, 211, 243, 147, @@ -141,24 +175,20 @@ mod tests { #[cfg(feature = "alloc")] const HASH_ZERO: &str = "ed1382037800c9dd938dd8854f1a8863bcdeb6705069b4b56a66ec22519d5829"; - #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Default, Hash)] - pub struct TestHashTag; + #[derive(Clone)] + pub struct TestTag; - impl sha256t::Tag for TestHashTag { - fn engine() -> sha256::HashEngine { - // The TapRoot TapLeaf midstate. + impl Tag for TestTag { + fn engine() -> HashEngine { let midstate = sha256::Midstate::from_byte_array(TEST_MIDSTATE); - sha256::HashEngine::from_midstate(midstate, 64) + let inner = sha256::HashEngine::from_midstate(midstate, 64); + HashEngine(inner, PhantomData) } } - // We support manually implementing `Tag` and creating a tagged hash from it. - #[cfg(feature = "alloc")] - pub type TestHash = sha256t::Hash; - #[test] #[cfg(feature = "alloc")] fn manually_created_sha256t_hash_type() { - assert_eq!(TestHash::hash(&[0]).to_string(), HASH_ZERO); + assert_eq!(Hash::::hash(&[0]).to_string(), HASH_ZERO); } }