PHP Manual
PrevNext

openssl_csr_sign

(PHP 4 >= 4.2.0, PHP 5)

openssl_csr_sign -- Sign a CSR with another certificate (or itself) and generate a certificate

Description

resource openssl_csr_sign ( mixed csr, mixed cacert, mixed priv_key, int days [, array configargs [, int serial]])

openssl_csr_sign() generates an x509 certificate resource from the csr previously generated by openssl_csr_new(), but it can also be the path to a PEM encoded CSR when specified as file://path/to/csr or an exported string generated by openssl_csr_export(). The generated certificate will be signed by cacert. If cacert is NULL, the generated certificate will be a self-signed certificate. priv_key is the private key that corresponds to cacert. days specifies the length of time for which the generated certificate will be valid, in days. You can finetune the CSR signing by configargs. See openssl_csr_new() for more information about configargs. Since PHP 4.3.3 you can specify the serial number of issued certificate by serial. In earlier versions, it was always 0.

Returns an x509 certificate resource on success, FALSE on failure.

Note: 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.

Example 1. openssl_csr_sign() example - signing a CSR (how to implement your own CA)

<?php
// Let's assume that this script is set to receive a CSR that has
// been pasted into a textarea from another page
$csrdata = $_POST["CSR"];

// We will sign the request using our own "certificate authority"
// certificate.  You can use any certificate to sign another, but
// the process is worthless unless the signing certificate is trusted
// by the software/users that will deal with the newly signed certificate

// We need our CA cert and its private key
$cacert = "file://path/to/ca.crt";
$privkey = array("file://path/to/ca.key", "your_ca_key_passphrase");

$userscert = openssl_csr_sign($csrdata, $cacert, $privkey, 365);

// Now display the generated certificate so that the user can
// copy and paste it into their local configuration (such as a file
// to hold the certificate for their SSL server)
openssl_x509_export($usercert, $certout);
echo $certout;

// Show any errors that occurred here
while (($e = openssl_error_string()) !== false) {
    echo $e . "\n";
}
?>

PrevHomeNext
openssl_csr_newUpopenssl_error_string
gt; "The Brain Room Limited",
    "organizationalUnitName" => "PHP Documentation Team",
    "commonName" => "Wez Furlong",
    "emailAddress" => "wez@example.com"
);

// Generate a new private (and public) key pair
$privkey = openssl_pkey_new();

// Generate a certificate signing request
$csr = openssl_csr_new($dn, $privkey);

// You will usually want to create a self-signed certificate at this
// point until your CA fulfills your request.
// This creates a self-signed cert that is valid for 365 days
$sscert = openssl_csr_sign($csr, null, $privkey, 365);

// Now you will want to preserve your private key, CSR and self-signed
// cert so that they can be installed into your web server, mail server
// or mail client (depending on the intended use of the certificate).
// This example shows how to get those things into variables, but you
// can also store them directly into files.
// Typically, you will send the CSR on to your CA who will then issue
// you with the "real" certificate.
openssl_csr_export($csr, $csrout) and var_dump($csrout);
openssl_x509_export($sscert, $certout) and var_dump($certout);
openssl_pkey_export($privkey, $pkeyout, "mypassword") and var_dump($pkeyout);

// Show any errors that occurred here
while (($e = openssl_error_string()) !== false) {
    echo $e . "\n";
}
?>