openssl_dh_compute_key
PHP 5 >= 5.3.0, PHP 7, PHP 8
openssl_dh_compute_key - Computes shared secret for public value of remote DH public key and local DH key
Manual
openssl_dh_compute_key(
string$public_key,
OpenSSLAsymmetricKey$private_key ): string|false
The shared secret returned by openssl_dh_compute_key is often used as an encryption key to secretly communicate with a remote party. This is known as the Diffie-Hellman key exchange.
Note:
ECDH is only supported as of PHP 8.1.0 and OpenSSL 3.0.0.
Parameters
- public_key
-
DH Public key of the remote party.
- private_key
-
A local DH private key, corresponding to the public key to be shared with the remote party.
Return Values
Returns shared secret on success or false on failure.
Changelog
| Version | Description |
| 8.0.0 | private_key accepts an OpenSSLAsymmetricKey now; previously, a resource of type OpenSSL key was accepted. |