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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

579 bytes · SHA-256 483ea0dcf7b35dd9… · View upstream ↗

1// Copyright (c) 2018-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <util/bytevectorhash.h>
6
7#include <crypto/siphash.h>
8#include <random.h>
9
10#include <span>
11#include <vector>
12
13ByteVectorHash::ByteVectorHash() :
14    m_k0(FastRandomContext().rand64()),
15    m_k1(FastRandomContext().rand64())
16{
17}
18
19size_t ByteVectorHash::operator()(const std::vector<unsigned char>& input) const
20{
21    return CSipHasher(m_k0, m_k1).Write(input).Finalize();
22}
23

FILE GUIDE · KEY SECTIONS

Salted SipHash for byte-vector containers

ByteVectorHash initializes two random keys and uses them to hash byte vectors for local container lookup.

Line 13 ↗

Give each hasher its own key pair

FastRandomContext supplies two 64-bit values. Per-instance keys make table placement less predictable to an attacker choosing inputs. These are internal hash-table keys, not wallet private keys.

Line 19 ↗

Hash the complete byte sequence

CSipHasher processes the vector and finalizes the keyed hash. The size_t result is for a container bucket calculation, not a transaction identifier or a portable value to persist and compare across processes.

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