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sodium_crypto_aead_chacha20poly1305_ietf_decrypt

PHP function Edit on GitHub ✎

(PHP 7 >= 7.2.0, PHP 8)

Verify that the ciphertext includes a valid tag

Description

sodium_crypto_aead_chacha20poly1305_ietf_decrypt(string $ciphertext, string $additional_data, string $nonce, string $key): string|false

Verify then decrypt with ChaCha20-Poly1305 (IETF variant).

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

ciphertext: Must be in the format provided by sodium_crypto_aead_chacha20poly1305_ietf_encrypt() (ciphertext and tag, concatenated).
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).

Returns the plaintext on success, Falseforfailure.