jam_std_common/crypto/
hashing.rs

1use jam_types::Hash;
2use scale::{Encode, Output};
3use tiny_keccak::{Hasher, Keccak};
4
5pub fn keccak(data: &[u8]) -> Hash {
6	let mut hasher = Keccak::v256();
7	hasher.update(data);
8	let mut output = [0u8; 32];
9	hasher.finalize(&mut output);
10	output
11}
12
13/// Compute Keccak hash of the concatenation of byte slices.
14pub fn keccak_concat<I, T>(items: I) -> Hash
15where
16	I: IntoIterator<Item = T>,
17	T: AsRef<[u8]>,
18{
19	let mut hasher = Keccak::v256();
20	for item in items.into_iter() {
21		hasher.update(item.as_ref());
22	}
23	let mut output = [0u8; 32];
24	hasher.finalize(&mut output);
25	output
26}
27
28pub fn hash_raw(data: &[u8]) -> Hash {
29	let mut hasher = Blake2bHasher::new();
30	hasher.update(data);
31	hasher.into_hash()
32}
33
34/// Compute the hash of the concatenation of byte slices.
35pub fn hash_raw_concat<I, T>(items: I) -> Hash
36where
37	I: IntoIterator<Item = T>,
38	T: AsRef<[u8]>,
39{
40	let mut hasher = Blake2bHasher::new();
41	for item in items.into_iter() {
42		hasher.update(item.as_ref());
43	}
44	hasher.into_hash()
45}
46
47pub fn hash_encoded(what: &impl Encode) -> Hash {
48	let mut hasher = Blake2bHasher::new();
49	what.encode_to(&mut hasher);
50	hasher.into_hash()
51}
52
53struct Blake2bHasher {
54	state: blake2b_simd::State,
55}
56
57impl Blake2bHasher {
58	fn new() -> Self {
59		let state = blake2b_simd::Params::new().hash_length(32).to_state();
60		Self { state }
61	}
62
63	fn update(&mut self, data: &[u8]) {
64		self.state.update(data);
65	}
66
67	fn into_hash(self) -> Hash {
68		self.state.finalize().as_bytes().try_into().expect("Hash length set to 32")
69	}
70}
71
72impl Output for Blake2bHasher {
73	fn write(&mut self, bytes: &[u8]) {
74		self.update(bytes);
75	}
76}
77
78#[cfg(test)]
79mod tests {
80	use super::*;
81
82	#[test]
83	fn hash_encoded_works() {
84		#[derive(Encode)]
85		struct Dummy {
86			x: Vec<Dummy>,
87			y: u64,
88			z: String,
89		}
90		let dummy = Dummy {
91			x: vec![Dummy { x: Vec::new(), y: 123, z: "Hello".into() }],
92			y: 333,
93			z: "world".into(),
94		};
95		assert_eq!(hash_raw(&dummy.encode()), hash_encoded(&dummy));
96		assert_eq!(dummy.using_encoded(hash_raw), hash_encoded(&dummy));
97	}
98
99	#[test]
100	fn hash_raw_concat_works() {
101		assert_eq!(
102			hash_raw(&[b"x".as_ref(), b"y", b"z"].concat()),
103			hash_raw_concat([b"x", b"y", b"z"])
104		);
105	}
106
107	#[test]
108	fn keccak_concat_works() {
109		assert_eq!(
110			keccak(&[b"x".as_ref(), b"y", b"z"].concat()),
111			keccak_concat([b"x", b"y", b"z"])
112		);
113	}
114}
jam_std_common/crypto/hashing.rs

jam_std_common/crypto/
hashing.rs
