sodium_crypto_aead_chacha20poly1305_ietf_encrypt

(PHP 7 >= 7.2.0, PHP 8)

sodium_crypto_aead_chacha20poly1305_ietf_encrypt — Encrypt a message

说明

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.

参数

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).

返回值

Returns the ciphertext and tag on success, 或者在失败时返回 false.

User Contributed Notes

craig at craigfrancis dot co dot uk 23-Jan-2018 01:37


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