openssl_pkey_new() generates a new private and public
key pair. The public component of the key can be obtained using
openssl_pkey_get_public().
You can finetune the key generation (such as specifying the number of
bits) using configargs. See
openssl_csr_new() for more information about
configargs.
Замечание:
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.