Supported Versions: PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8
Sign a CSR with another certificate (or itself) and generate a certificate
openssl_csr_sign( OpenSSLCertificateSigningRequest|string $csr, OpenSSLCertificate|string|null $ca_certificate, OpenSSLAsymmetricKey|OpenSSLCertificate|array|string $private_key, int $days, ?array $options = null, int $serial = 0): OpenSSLCertificate|false