Supported Versions: PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8
Decrypts an S/MIME encrypted message
<?php openssl_pkcs7_decrypt( string $input_filename, string $output_filename, OpenSSLCertificate|string $certificate, OpenSSLAsymmetricKey|OpenSSLCertificate|array|string|null $private_key = null): bool