SodiumNonceLengthMismatch

warning native on by default quick-fix PHP ≥ 7.2

Group: Probable bugs

Secretbox requires its defined nonce byte length. Construct the nonce using the extension's required-length constant.

Example

Before

<?php
$c=sodium_crypto_secretbox($message,random_bytes(12),$key);

After fix

<?php
$c=sodium_crypto_secretbox($message,random_bytes(\SODIUM_CRYPTO_SECRETBOX_NONCEBYTES),$key);

Reported:

• line 2: Use the required secretbox nonce length.

Detection

• Resolved sodium_crypto_secretbox second argument has known byte length other than 24. Recognize literal strings, str_repeat of literal strings and literal counts, and random_bytes of a positive literal count. Highlight nonce.
• Resolve builtin functions, classes, constants and methods; user-defined lookalikes are excluded. Follow only bounded local proof in one lexical scope.
• Emit one finding per violating operation, not per supporting evidence statement. When the proof is inconclusive, nothing is reported.

Exceptions (no report)

• Do not report unresolved or shadowed builtin names, unknown values, or incomplete receiver/type provenance. Unknown calls, aliases escaping, and intervening writes invalidate local proof. Similar code outside the stated detection contract is not a finding.
• Both standard suppression forms suppress this native ID.

Fix

F1. When the nonce is a direct resolved random_bytes call with a positive literal length, replace only that length node with \SODIUM_CRYPTO_SECRETBOX_NONCEBYTES. Preserve comments and argument formatting outside the literal span. Do not fix stored random-byte results, dynamic or variable counts, string literals, or other nonce constructors.

PHP versions

Requires PHP 7.2 or later.

Configure

In custos.json:

{
  "rules": {
    "SodiumNonceLengthMismatch": {
      "enabled": false
    }
  }
}

Suppress

Before the statement or declaration (or the first statement of the file):

// @custos-ignore SodiumNonceLengthMismatch