PHP RFC: Integrating BLAKE3 into PHP

Version: 0.1

Date: 2025-01-24

Author: Hans Henrik Bergan, hans@loltek.net

Status: Draft

First Published at: http://wiki.php.net/rfc/blake3

TL;DR: Essentially, BLAKE3 provides SHA3-256–level security at considerably higher throughput.

BLAKE3 is a cryptographic hash function based on the SHA3-finalist BLAKE, offering SHA3-256-like security at much higher speed. Benchmarks from /ext/hash/bench.php highlight BLAKE3's performance: it is over four times faster than SHA3-256 on AMD Ryzen 9 7950x, with BLAKE3 completing bench.php in 0.007752 seconds versus SHA3-256's 0.031518 seconds. /ext/hash/bench.php chart on AMD Ryzen 9 7950x, excluding non-cryptographic hashes:

And here is a chart from the BLAKE3 developers:

This RFC proposes adding BLAKE3 support to PHP, offering performance and security assurance to developers requiring hashing functionality.

The proposal is to integrate BLAKE3 into PHP as a supported algorithm in the ext/hash extension. Developers will be able to use the familiar hash() function and related APIs to compute BLAKE3 hashes.

Example usage:

<?php
// Compute a BLAKE3 hash
$hash = hash('blake3', 'The quick brown fox jumps over the lazy dog');
echo $hash, PHP_EOL; // 2f1514181aadccd913abd94cfa592701a5686ab23f8df1dff1b74710febc6d4a
 
// Compute a keyed BLAKE3 hash
$key = 'secret-key';
$hash_keyed = hash_hmac('blake3', 'The quick brown fox jumps over the lazy dog', $key);
echo $hash_keyed, PHP_EOL;
?>

The integration will include:

Support for the blake3 algorithm in the hash() function.

Support for keyed hashing (HMAC) with hash_hmac().

Updated documentation for ext/hash to include examples and usage of BLAKE3.

No backward-incompatible changes are introduced by this RFC. The addition of BLAKE3 is purely additive and does not modify existing functionality.

This feature is proposed for inclusion in the next PHP 8.x release.

No impact is expected on CLI, Development web server, or embedded PHP.

The ext/hash extension will be updated to include BLAKE3. This change will not affect other extensions.

There is no expected impact on Opcache.

No new constants are introduced.

No new php.ini settings are required for this feature.

There are currently no open issues related to this RFC.

This RFC does not impact existing hashing algorithms or functionality in PHP.

Future enhancements to BLAKE3 support could include:

• Multi-threaded hashing for even greater performance on large inputs. There is no multithreading support in the current ext/hash apis.
• Support for extended output modes of BLAKE3 (e.g., XOF functionality). There is no XOF support in the current ext/hash apis.

The implementation is available as a pull request at https://github.com/php/php-src/pull/13194. Tests have been included as part of the pull request, ensuring the correctness and reliability of the implementation.

After approval, this section will include:

The version(s) the feature was merged into.

A link to the git commit(s).

A link to the PHP manual entry for the feature.

BLAKE3 Official Website: https://blake3.io/

BLAKE3 Specification: https://github.com/BLAKE3-team/BLAKE3-specs/blob/master/blake3.pdf

PHP Pull Request for BLAKE3 Support: https://github.com/php/php-src/pull/13194

No features have been rejected during the discussion of this RFC.