Generates a new private key

Description

openssl_pkey_new(?array $options = null): OpenSSLAsymmetricKey|false

openssl_pkey_new() generates a new private key. How to obtain the public component of the key is shown in an example below.

Note: You need to have a valid openssl.cnf installed for this function to operate correctly. See the notes under the installation section for more information.

Parameters

options: You can finetune the key generation (such as specifying the number of bits) using options. See openssl_csr_new() for more information about options.

Return Values

Returns an OpenSSLAsymmetricKey instance for the pkey on success, or false on error.

Changelog

Version	Description
8.0.0	On success, this function returns an OpenSSLAsymmetricKey instance now; previously, a resource of type `OpenSSL key` was returned.
7.1.0	The `curve_name` option was added to make it possible to create EC keys.

Examples

Example #1 Obtain the public key from a private key

<?php
$private_key = openssl_pkey_new();
$public_key_pem = openssl_pkey_get_details($private_key)['key'];
echo $public_key_pem;
$public_key = openssl_pkey_get_public($public_key_pem);
var_dump($public_key);
?>

The above example will output something similar to:

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEArZFsmN2P6rx1Xt7YV95o
gcdlal0k3ryiIhFNzjwtRNNTXfEfBr6lUuaIJYQ8/XqEBX0hpcfuuF6tTRlonA3t
WLME0QFD93YVsAaXcy76YqjjqcRRodIBphAbYyyMI/lXkQAdn7kbAmr7neSOsMYJ
El9Wo4Hl4oG6e52ZnYHyqW9dxh4hX93eupR2TmcCdVf+r9xoHewP0KJYSHt7vDUX
AQlWYcQiWHIadFsmL0orr6mutlXFReoHbesgKY9/3YLOu0JfxflSjIZ2JeL1NTl1
MsmODsUwgAUrwnWKKx+eQUP5g3GnSB3dPkRh9zRVRiLNWbCugyjrf3e6DgQWrW7j
pwIDAQAB
-----END PUBLIC KEY-----
resource(5) of type (OpenSSL key)