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openssl_pkey_get_public

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

openssl_pkey_get_public — Extract public key from certificate and prepare it for use

Description

openssl_pkey_get_public(OpenSSLAsymmetricKey|OpenSSLCertificate|array|string $public_key): OpenSSLAsymmetricKey|false

openssl_pkey_get_public() extracts the public key from public_key and prepares it for use by other functions.

Parameters

public_key

public_key can be one of the following:

  1. an OpenSSLAsymmetricKey instance
  2. a string having the format file://path/to/file.pem. The named file must contain a PEM encoded certificate/public key (it may contain both).
  3. A PEM formatted public key.

Return Values

Returns an OpenSSLAsymmetricKey instance 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.
8.0.0 public_key accepts an OpenSSLAsymmetricKey or OpenSSLCertificate instance now; previously, a resource of type OpenSSL key or OpenSSL X.509 was accepted.

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.openssl-pkey-get-public.php