Forward port blake2 storage support (#2360)

* move storage maps to blake2_128 (#2268)

* remove default hash, introduce twox_128 and blake2

* use blake2_128 & create ext_blake2_128

* refactor code

* add benchmark

* factorize generator

* fix

* parameterizable hasher

* some fix

* fix

* fix

* fix

* metadata

* fix

* remove debug print

* map -> blake2_256

* fix test

* fix test

* Apply suggestions from code review

Co-Authored-By: thiolliere <gui.thiolliere@gmail.com>

* impl twox 128 concat (#2353)

* impl twox_128_concat

* comment addressed

* fix

* impl twox_128->64_concat

* fix test

* Fix compilation and cleanup some docs

* Apply suggestions from code review

Co-Authored-By: bkchr <bkchr@users.noreply.github.com>

substrate/core/primitives/Cargo.toml

@@ -31,8 +31,10 @@ regex = {version = "1.1", optional = true }
 
 [dev-dependencies]
 substrate-serializer = { path = "../serializer" }
-pretty_assertions = "0.6.1"
-heapsize = "0.4.2"
+pretty_assertions = "0.6"
+heapsize = "0.4"
+hex-literal = "0.1"
+rand = "0.6"
 
 [features]
 default = ["std"]

substrate/core/primitives/benches/benches.rs

@@ -0,0 +1,60 @@
+// Copyright 2019 Parity Technologies
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// TODO: Move benchmark to criterion #2354
+#![feature(test)]
+
+extern crate test;
+use hex_literal::{hex, hex_impl};
+use substrate_primitives::hashing::{twox_128, blake2_128};
+
+
+const MAX_KEY_SIZE: u32 = 32;
+
+fn data_set() -> Vec<Vec<u8>> {
+	use rand::SeedableRng;
+	use rand::Rng;
+
+	let rnd: [u8; 32] = rand::rngs::StdRng::seed_from_u64(12).gen();
+	let mut rnd = rnd.iter().cycle();
+	let mut res = Vec::new();
+	for size in 1..=MAX_KEY_SIZE {
+		for _ in 0..1_000 {
+			let value = (0..size)
+				.map(|_| rnd.next().unwrap().clone())
+				.collect();
+			res.push(value);
+		}
+	}
+	res
+}
+
+fn bench_hash_128(b: &mut test::Bencher, f: &Fn(&[u8]) -> [u8; 16]) {
+	let data_set = data_set();
+	b.iter(|| {
+		for data in &data_set {
+			let _a = f(data);
+		}
+	});
+}
+
+#[bench]
+fn bench_blake2_128(b: &mut test::Bencher) {
+	bench_hash_128(b, &blake2_128);
+}
+
+#[bench]
+fn bench_twox_128(b: &mut test::Bencher) {
+	bench_hash_128(b, &twox_128);
+}

substrate/core/primitives/src/hashing.rs

@@ -55,6 +55,23 @@ pub fn blake2_128(data: &[u8]) -> [u8; 16] {
 	r
 }
 
+/// Do a XX 64-bit hash and place result in `dest`.
+pub fn twox_64_into(data: &[u8], dest: &mut [u8; 8]) {
+	use ::core::hash::Hasher;
+	let mut h0 = twox_hash::XxHash::with_seed(0);
+	h0.write(data);
+	let r0 = h0.finish();
+	use byteorder::{ByteOrder, LittleEndian};
+	LittleEndian::write_u64(&mut dest[0..8], r0);
+}
+
+/// Do a XX 64-bit hash and return result.
+pub fn twox_64(data: &[u8]) -> [u8; 8] {
+	let mut r: [u8; 8] = [0; 8];
+	twox_64_into(data, &mut r);
+	r
+}
+
 /// Do a XX 128-bit hash and place result in `dest`.
 pub fn twox_128_into(data: &[u8], dest: &mut [u8; 16]) {
 	use ::core::hash::Hasher;

substrate/core/primitives/src/lib.rs

@@ -46,7 +46,7 @@ pub use impl_serde::serialize as bytes;
 #[cfg(feature = "std")]
 pub mod hashing;
 #[cfg(feature = "std")]
-pub use hashing::{blake2_256, twox_128, twox_256};
+pub use hashing::{blake2_128, blake2_256, twox_64, twox_128, twox_256};
 #[cfg(feature = "std")]
 pub mod hexdisplay;
 pub mod crypto;