138 lines
3.4 KiB
Rust
138 lines
3.4 KiB
Rust
//! The `hash` module provides functions for creating SHA-256 hashes.
|
|
|
|
use bs58;
|
|
use sha2::{Digest, Sha256};
|
|
use std::convert::TryFrom;
|
|
use std::fmt;
|
|
use std::mem;
|
|
use std::str::FromStr;
|
|
|
|
#[derive(Serialize, Deserialize, Clone, Copy, Default, Eq, PartialEq, Ord, PartialOrd, Hash)]
|
|
#[repr(transparent)]
|
|
pub struct Hash([u8; 32]);
|
|
|
|
#[derive(Clone, Default)]
|
|
pub struct Hasher {
|
|
hasher: Sha256,
|
|
}
|
|
|
|
impl Hasher {
|
|
pub fn hash(&mut self, val: &[u8]) {
|
|
self.hasher.input(val);
|
|
}
|
|
pub fn hashv(&mut self, vals: &[&[u8]]) {
|
|
for val in vals {
|
|
self.hash(val);
|
|
}
|
|
}
|
|
pub fn result(self) -> Hash {
|
|
// At the time of this writing, the sha2 library is stuck on an old version
|
|
// of generic_array (0.9.0). Decouple ourselves with a clone to our version.
|
|
Hash(<[u8; 32]>::try_from(self.hasher.result().as_slice()).unwrap())
|
|
}
|
|
}
|
|
|
|
impl AsRef<[u8]> for Hash {
|
|
fn as_ref(&self) -> &[u8] {
|
|
&self.0[..]
|
|
}
|
|
}
|
|
|
|
impl fmt::Debug for Hash {
|
|
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
|
|
write!(f, "{}", bs58::encode(self.0).into_string())
|
|
}
|
|
}
|
|
|
|
impl fmt::Display for Hash {
|
|
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
|
|
write!(f, "{}", bs58::encode(self.0).into_string())
|
|
}
|
|
}
|
|
|
|
#[derive(Debug, Clone, PartialEq, Eq)]
|
|
pub enum ParseHashError {
|
|
WrongSize,
|
|
Invalid,
|
|
}
|
|
|
|
impl FromStr for Hash {
|
|
type Err = ParseHashError;
|
|
|
|
fn from_str(s: &str) -> Result<Self, Self::Err> {
|
|
let bytes = bs58::decode(s)
|
|
.into_vec()
|
|
.map_err(|_| ParseHashError::Invalid)?;
|
|
if bytes.len() != mem::size_of::<Hash>() {
|
|
Err(ParseHashError::WrongSize)
|
|
} else {
|
|
Ok(Hash::new(&bytes))
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Hash {
|
|
pub fn new(hash_slice: &[u8]) -> Self {
|
|
Hash(<[u8; 32]>::try_from(hash_slice).unwrap())
|
|
}
|
|
}
|
|
|
|
/// Return a Sha256 hash for the given data.
|
|
pub fn hashv(vals: &[&[u8]]) -> Hash {
|
|
let mut hasher = Hasher::default();
|
|
hasher.hashv(vals);
|
|
hasher.result()
|
|
}
|
|
|
|
/// Return a Sha256 hash for the given data.
|
|
pub fn hash(val: &[u8]) -> Hash {
|
|
hashv(&[val])
|
|
}
|
|
|
|
/// Return the hash of the given hash extended with the given value.
|
|
pub fn extend_and_hash(id: &Hash, val: &[u8]) -> Hash {
|
|
let mut hash_data = id.as_ref().to_vec();
|
|
hash_data.extend_from_slice(val);
|
|
hash(&hash_data)
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
use bs58;
|
|
|
|
#[test]
|
|
fn test_hash_fromstr() {
|
|
let hash = hash(&[1u8]);
|
|
|
|
let mut hash_base58_str = bs58::encode(hash).into_string();
|
|
|
|
assert_eq!(hash_base58_str.parse::<Hash>(), Ok(hash));
|
|
|
|
hash_base58_str.push_str(&bs58::encode(hash.0).into_string());
|
|
assert_eq!(
|
|
hash_base58_str.parse::<Hash>(),
|
|
Err(ParseHashError::WrongSize)
|
|
);
|
|
|
|
hash_base58_str.truncate(hash_base58_str.len() / 2);
|
|
assert_eq!(hash_base58_str.parse::<Hash>(), Ok(hash));
|
|
|
|
hash_base58_str.truncate(hash_base58_str.len() / 2);
|
|
assert_eq!(
|
|
hash_base58_str.parse::<Hash>(),
|
|
Err(ParseHashError::WrongSize)
|
|
);
|
|
|
|
let mut hash_base58_str = bs58::encode(hash.0).into_string();
|
|
assert_eq!(hash_base58_str.parse::<Hash>(), Ok(hash));
|
|
|
|
// throw some non-base58 stuff in there
|
|
hash_base58_str.replace_range(..1, "I");
|
|
assert_eq!(
|
|
hash_base58_str.parse::<Hash>(),
|
|
Err(ParseHashError::Invalid)
|
|
);
|
|
}
|
|
}
|