PHP sodium_crypto_shorthash_keygen() Function: Usage and Examples

sodium_crypto_shorthash_keygen generates a securely random secret key with the exact size required by its matching primitive.

The examples explain the data format, expected results and the difference between this API and nearby cryptographic operations.

What It Does

The operation is intended for: sodium_crypto_shorthash_keygen generates a securely random secret key with the exact size required by its matching primitive.

The sodium extension must be enabled.

Syntax and Return Value

sodium_crypto_shorthash_keygen(): string

This API accepts no required parameters, or its signature must be checked on the target runtime.

The declared return type is shown above. Errors can include false results or exceptions depending on this API: The short output is not collision resistant enough for document integrity, signatures or password hashing.

Example 1: Basic Operation

SipHash is meant for short hash-table fingerprints, not collision-resistant document integrity.

<?php
$key = sodium_crypto_shorthash_keygen();
echo strlen($key) === SODIUM_CRYPTO_SHORTHASH_KEYBYTES ? "correct size" : "wrong size";

Example 2: A Different Use Case

Generate two independent keys and confirm the expected length and distinct random values.

<?php
// Check the alternative case.
$key = sodium_crypto_shorthash_keygen();
$second = sodium_crypto_shorthash_keygen();
var_dump(!hash_equals($key, $second));
echo strlen($key) === SODIUM_CRYPTO_SHORTHASH_KEYBYTES ? "correct size" : "wrong size";

Practical Example: Checking the Result

Generate two independent keys and confirm the expected length and distinct random values.

<?php
// Verify the expected behavior before using results.
$key = sodium_crypto_shorthash_keygen();
$second = sodium_crypto_shorthash_keygen();
var_dump(strlen($second) === strlen($key) && !hash_equals($key, $second));
echo strlen($key) === SODIUM_CRYPTO_SHORTHASH_KEYBYTES ? "correct size" : "wrong size";

Important Behavior and Edge Cases

The short output is not collision resistant enough for document integrity, signatures or password hashing.

The short output is not collision resistant enough for document integrity, signatures or password hashing.

Comparison with Related Functions

Common Beginner Mistakes

Key Takeaways

• sodium_crypto_shorthash_keygen generates a securely random secret key with the exact size required by its matching primitive.
• The short output is not collision resistant enough for document integrity, signatures or password hashing.
• sodium_crypto_generichash supports larger digests for document hashing.

Apply this behavior to a real application only after confirming the required extension, configuration and failure handling on the deployment runtime.