CascadiaPHP 2024


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

openssl_pkey_get_privateGet a private key


openssl_pkey_get_private() parses private_key and prepares it for use by other functions.



private_key can be one of the following:

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


The optional parameter passphrase must be used if the specified key is encrypted (protected by a passphrase).

Return Values

Returns an OpenSSLAsymmetricKey instance on success, or false on error.


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 private_key accepts an OpenSSLAsymmetricKey or OpenSSLCertificate instance now; previously, a resource of type OpenSSL key or OpenSSL X.509 was accepted.
8.0.0 passphrase is nullable now.
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User Contributed Notes 2 notes

kristof1 at mailbox dot hu
10 years ago
It's actually "file://key.pem" when you want to give a relative path using unix systems. It will be three '/' in case of absolute path (e.g "file:///home/username/..."). But this path consists of two '/' originated from "file://" and one '/' from the fact that home is a subfolder of the unix filesystem's root directory ("/home/username/..."). This two part will be concatenated and you will get three '/' characters following each other.

So you only have to concatenate "file://" with an existing path string in every case.
pablo dot siciliano at gmail dot com
3 years ago

If this function not work with pathname try with a file_get_contents of a key file.
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