openssl_pkcs7_sign
(PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8)
openssl_pkcs7_sign — Sign an S/MIME message
Description
string
$input_filename,string
$output_filename,OpenSSLCertificate|string
$certificate,OpenSSLAsymmetricKey|OpenSSLCertificate|array|string
$private_key,?array
$headers,int
$flags = PKCS7_DETACHED,?string
$untrusted_certificates_filename = null): bool
openssl_pkcs7_sign() takes the contents of the file
named input_filename and signs them using the
certificate and its matching private key specified by
certificate and private_key
parameters.
Parameters
-
input_filename -
The input file you are intending to digitally sign.
-
output_filename -
The file which the digital signature will be written to.
-
certificate -
The X.509 certificate used to digitally sign
input_filename. See Key/Certificate parameters for a list of valid values. -
private_key -
private_keyis the private key corresponding tocertificate. See Public/Private Key parameters for a list of valid values. -
headers -
headersis an array of headers that will be prepended to the data after it has been signed (see openssl_pkcs7_encrypt() for more information about the format of this parameter). -
flags -
flagscan be used to alter the output - see PKCS7 constants. -
untrusted_certificates_filename -
untrusted_certificates_filenamespecifies the name of a file containing a bunch of extra certificates to include in the signature which can for example be used to help the recipient to verify the certificate that you used.
Return Values
Returns true on success or false on failure.
Changelog
| Version | Description |
|---|---|
| 8.0.0 |
certificate accepts an OpenSSLCertificate instance now;
previously, a resource of type OpenSSL X.509 CSR was accepted.
|
| 8.0.0 |
private_key accepts an OpenSSLAsymmetricKey
or OpenSSLCertificate instance now;
previously, a resource of type OpenSSL key or OpenSSL X.509 CSR
was accepted.
|
Examples
Example #1 openssl_pkcs7_sign() example
<?php
// the message you want to sign so that recipient can be sure it was you that
// sent it
$data = <<<EOD
You have my authorization to spend $10,000 on dinner expenses.
The CEO
EOD;
// save message to file
$fp = fopen("msg.txt", "w");
fwrite($fp, $data);
fclose($fp);
// encrypt it
if (openssl_pkcs7_sign("msg.txt", "signed.txt", "file://mycert.pem",
array("file://mycert.pem", "mypassphrase"),
array("To" => "joes@example.com", // keyed syntax
"From: HQ <ceo@example.com>", // indexed syntax
"Subject" => "Eyes only")
)) {
// message signed - send it!
exec(ini_get("sendmail_path") . " < signed.txt");
}
?>
