Perl Requires Chilkat v11.0.0+

Generate a CSR with keyUsage, extKeyUsage, and other Extensions

See more CSR Examples

Demonstrates how to generate a CSR containing a 1.2.840.113549.1.9.14 extensionRequest with the following extensions:

• 1.3.6.1.4.1.311.20.2 enrollCerttypeExtension
• 2.5.29.15 keyUsage
• 2.5.29.37 extKeyUsage
• 2.5.29.14 subjectKeyIdentifier

Perl

use chilkat();

$success = 0;

#  This requires the Chilkat API to have been previously unlocked.
#  See Global Unlock Sample for sample code.

#  This example will generate a secp256r1 ECDSA key for the CSR.
$ecc = chilkat::CkEcc->new();
$prng = chilkat::CkPrng->new();
$privKey = chilkat::CkPrivateKey->new();
$success = $ecc->GenKey("secp256r1",$prng,$privKey);
if ($success == 0) {
    print "Failed to generate a new ECDSA private key." . "\r\n";
    exit;
}

$csr = chilkat::CkCsr->new();

#  Add common CSR fields:
$csr->put_CommonName("mysubdomain.mydomain.com");
$csr->put_Country("GB");
$csr->put_State("Yorks");
$csr->put_Locality("York");
$csr->put_Company("Internet Widgits Pty Ltd");
$csr->put_EmailAddress('support@mydomain.com');

#  Add the following 1.2.840.113549.1.9.14 extensionRequest
#  Note: The easiest way to know the content and format of the XML to be added is to examine
#  a pre-existing CSR with the same desired extensionRequest.  You can use Chilkat to
#  get the extensionRequest from an existing CSR. 

#  Here is a sample extension request:

#  <?xml version="1.0" encoding="utf-8"?>
#  <set>
#      <sequence>
#          <sequence>
#              <oid>1.3.6.1.4.1.311.20.2</oid>
#              <asnOctets>
#                  <universal tag="30" constructed="0">AEUAbgBkAEUAbgB0AGkAdAB5AEMAbABpAGUAbgB0AEEAdQB0AGgAQwBlAHIAdABpAGYAaQBjAGEAdABl
#  AF8AQwBTAFIAUABhAHMAcwB0AGgAcgBvAHUAZwBoAC8AVgAx</universal>
#              </asnOctets>
#          </sequence>
#          <sequence>
#              <oid>2.5.29.15</oid>
#              <bool>1</bool>
#              <asnOctets>
#                  <bits n="3">A0</bits>
#              </asnOctets>
#          </sequence>
#          <sequence>
#              <oid>2.5.29.37</oid>
#              <asnOctets>
#                  <sequence>
#                      <oid>1.3.6.1.5.5.7.3.3</oid>
#                  </sequence>
#              </asnOctets>
#          </sequence>
#          <sequence>
#              <oid>2.5.29.14</oid>
#              <asnOctets>
#                  <octets>MCzBMQAViXBz8IDt8LsgmJxJ4Xg=</octets>
#              </asnOctets>
#          </sequence>
#      </sequence>
#  </set>

#  Use this online tool to generate code from sample XML: 
#  Generate Code to Create XML

#  A few notes:
#  The string "AEUAbgBkAEUAbgB0AGkAdAB5AEMAbABpAGUAbgB0AEEAdQB0AGgAQwBlAHIAdABpAGYAaQBjAGEAdABlAF8AQwBTAFIAUABhAHMAcwB0AGgAcgBvAHUAZwBoAC8AVgAx"
#  is the base64 encoding of the utf-16be byte representation of the string "EndEntityClientAuthCertificate_CSRPassthrough/V1"

$s = "EndEntityClientAuthCertificate_CSRPassthrough/V1";
$bdTemp = chilkat::CkBinData->new();
$bdTemp->AppendString($s,"utf-16be");
$s_base64_utf16be = $bdTemp->getEncoded("base64");
#  The string should be "AEUA....."
print $s_base64_utf16be . "\r\n";

#  Here's the code to generate the above extension request.

$xml = chilkat::CkXml->new();
$xml->put_Tag("set");
$xml->UpdateChildContent("sequence|sequence|oid","1.3.6.1.4.1.311.20.2");
$xml->UpdateAttrAt("sequence|sequence|asnOctets|universal",1,"tag","30");
$xml->UpdateAttrAt("sequence|sequence|asnOctets|universal",1,"constructed","0");
$xml->UpdateChildContent("sequence|sequence|asnOctets|universal",$s_base64_utf16be);
$xml->UpdateChildContent("sequence|sequence[1]|oid","2.5.29.15");
$xml->UpdateChildContent("sequence|sequence[1]|bool","1");
$xml->UpdateAttrAt("sequence|sequence[1]|asnOctets|bits",1,"n","3");
#  A0 is hex for decimal 160.
$xml->UpdateChildContent("sequence|sequence[1]|asnOctets|bits","A0");
$xml->UpdateChildContent("sequence|sequence[2]|oid","2.5.29.37");
$xml->UpdateChildContent("sequence|sequence[2]|asnOctets|sequence|oid","1.3.6.1.5.5.7.3.3");

#  This is the subjectKeyIdentifier extension.
#  The string "MCzBMQAViXBz8IDt8LsgmJxJ4Xg=" is base64 that decodes to 20 bytes, which is a SHA1 hash.
#  This is simply a hash of the DER of the public key.

$pubKey = chilkat::CkPublicKey->new();
$privKey->ToPublicKey($pubKey);
$bdPubKeyDer = chilkat::CkBinData->new();
$bdPubKeyDer->AppendEncoded($pubKey->getEncoded(1,"base64"),"base64");
$ski = $bdPubKeyDer->getHash("sha1","base64");

$xml->UpdateChildContent("sequence|sequence[3]|oid","2.5.29.14");
$xml->UpdateChildContent("sequence|sequence[3]|asnOctets|octets",$ski);

#  Add the extension request to the CSR
$csr->SetExtensionRequest($xml);

#  Generate the CSR with the extension request
$csrPem = $csr->genCsrPem($privKey);
if ($csr->get_LastMethodSuccess() == 0) {
    print $csr->lastErrorText() . "\r\n";
    exit;
}

print $csrPem . "\r\n";