Encrypt a CMS message

Description

openssl_cms_encrypt(
    string $input_filename,
    string $output_filename,
    OpenSSLCertificate|array|string $certificate,
    ?array $headers,
    int $flags = 0,
    int $encoding = OPENSSL_ENCODING_SMIME,
    int $cipher_algo = OPENSSL_CIPHER_AES_128_CBC
): bool

This function encrypts content to one or more recipients, based on the certificates that are passed to it.

Parameters

input_filename: The file to be encrypted.
output_filename: The output file.
certificate: Recipients to encrypt to.
headers: Headers to include when S/MIME is used.
flags: Flags to be passed to CMS_sign.
encoding: An encoding to output. One of OPENSSL_CMS_SMIME, OPENSLL_CMS_DER or OPENSSL_CMS_PEM.
cipher_algo: A cypher to use.

Return Values

Returns true on success or false on failure.

Changelog

Version	Description
8.1.0	The default cipher algorithm (`cipher_algo`) is now AES-128-CBC (`OPENSSL_CIPHER_AES_128_CBC`). Previously, PKCS7/CMS was used (`OPENSSL_CIPHER_RC2_40`).