PHP 8.1.0 Released!

sodium_crypto_aead_chacha20poly1305_ietf_encrypt

(PHP 7 >= 7.2.0, PHP 8)

sodium_crypto_aead_chacha20poly1305_ietf_encryptEncrypt a message

Description

sodium_crypto_aead_chacha20poly1305_ietf_encrypt(
    string $message,
    string $additional_data,
    string $nonce,
    string $key
): string

Encrypt then authenticate with ChaCha20-Poly1305 (IETF variant).

The IETF variant uses 96-bit nonces and 32-bit internal counters, instead of 64-bit for both.

Liste de param├Ętres

message

The plaintext message to encrypt.

additional_data

Additional, authenticated data. This is used in the verification of the authentication tag appended to the ciphertext, but it is not encrypted or stored in the ciphertext.

nonce

A number that must be only used once, per message. 12 bytes long.

key

Encryption key (256-bit).

Valeurs de retour

Returns the ciphertext and tag on success, ou false si une erreur survient.

add a note add a note

User Contributed Notes 1 note

up
5
craig at craigfrancis dot co dot uk
3 years ago
Here's a quick example on how to use sodium_crypto_aead_chacha20poly1305_ietf_encrypt(); where you have 1 key to encrypt and decrypt.

<?php

$key
= sodium_crypto_aead_chacha20poly1305_ietf_keygen();

//--------------------------------------------------
// Encrypting

$message = 'hello';

$nonce = random_bytes(SODIUM_CRYPTO_AEAD_CHACHA20POLY1305_IETF_NPUBBYTES);

$encrypted = sodium_crypto_aead_chacha20poly1305_ietf_encrypt($message, $nonce, $nonce, $key);

echo
base64_encode($encrypted) . "\n";

//--------------------------------------------------
// Decrypting

$decrypted = sodium_crypto_aead_chacha20poly1305_ietf_decrypt($encrypted, $nonce, $nonce, $key);

echo
$decrypted . "\n";

?>

And just to confirm, the $nonce is used twice - the first time it's in the authentication tag ($ad):

https://twitter.com/craigfrancis/status/949614546259513344
To Top