C++

Validate Certificate using OCSP Protocol

See more Certificates Examples

Demonstrates how to validate a certificate (check the revoked status) using the OCSP protocol. C++

#include <CkCert.h>
#include <CkPrng.h>
#include <CkJsonObject.h>
#include <CkBinData.h>
#include <CkHttp.h>
#include <CkHttpResponse.h>

void ChilkatSample(void)
    {
    bool success = false;

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

    //  This example will check the revoked status of a certificate loaded from a file.
    CkCert cert;
    success = cert.LoadFromFile("qa_data/certs/google.crt");
    if (success == false) {
        std::cout << cert.lastErrorText() << "\r\n";
        return;
    }

    //  Get the cert's OCSP URL.
    const char *ocspUrl = cert.ocspUrl();

    //  Build the JSON that will be the OCSP request.

    //  Possible hash algorithms are sha1, sha256, sha384, sha512.  
    const char *hashAlg = "sha256";
    CkPrng prng;
    CkJsonObject json;
    json.put_EmitCompact(false);
    //  Read more about OCSP nonce lengths
    json.UpdateString("extensions.ocspNonce",prng.genRandom(16,"base64"));
    json.put_I(0);
    json.UpdateString("request[i].cert.hashAlg",hashAlg);
    json.UpdateString("request[i].cert.issuerNameHash",cert.hashOf("IssuerDN",hashAlg,"base64"));
    json.UpdateString("request[i].cert.issuerKeyHash",cert.hashOf("IssuerPublicKey",hashAlg,"base64"));
    json.UpdateString("request[i].cert.serialNumber",cert.serialNumber());

    std::cout << json.emit() << "\r\n";

    //  Our OCSP request looks something like this:
    //  {
    //    "extensions": {
    //      "ocspNonce": "qZDfbpO+nUxRzz6c/SPjE5QCAsPfpkQlRDxTnGl0gnxt7iXO"
    //    },
    //    "request": [
    //      {
    //        "cert": {
    //          "hashAlg": "sha1",
    //          "issuerNameHash": "9u2wY2IygZo19o11oJ0CShGqbK0=",
    //          "issuerKeyHash": "d8K4UJpndnaxLcKG0IOgfqZ+uks=",
    //          "serialNumber": "6175535D87BF94B6"
    //        }
    //      }
    //    ]
    //  }

    CkBinData ocspRequest;
    CkHttp http;

    //  Convert our JSON to a binary (ASN.1) OCSP request
    success = http.CreateOcspRequest(json,ocspRequest);
    if (success == false) {
        std::cout << http.lastErrorText() << "\r\n";
        return;
    }

    //  Send the OCSP request to the OCSP server
    CkHttpResponse resp;
    success = http.HttpBd("POST",ocspUrl,ocspRequest,"application/ocsp-request",resp);
    if (success == false) {
        std::cout << http.lastErrorText() << "\r\n";
        return;
    }

    //  Get the binary (ASN.1) OCSP reply
    CkBinData ocspReply;
    resp.GetBodyBd(ocspReply);

    //  Convert the binary reply to JSON.
    //  Also returns the overall OCSP response status.
    CkJsonObject jsonReply;
    int ocspStatus = http.ParseOcspReply(ocspReply,jsonReply);

    //  The ocspStatus can have one of these values:
    //  -1:  The ARG1 does not contain a valid OCSP reply.
    //  0:  Successful - Response has valid confirmations..
    //  1: Malformed request - Illegal confirmation request.
    //  2: Internal error - Internal error in issuer.
    //  3: Try later -  Try again later.
    //  4: Not used - This value is never returned.
    //  5: Sig required - Must sign the request.
    //  6: Unauthorized - Request unauthorized.

    if (ocspStatus < 0) {
        std::cout << "Invalid OCSP reply." << "\r\n";
        return;
    }

    std::cout << "Overall OCSP Response Status: " << ocspStatus << "\r\n";

    //  Let's examine the OCSP response (in JSON).
    jsonReply.put_EmitCompact(false);
    std::cout << jsonReply.emit() << "\r\n";

    //  The JSON reply looks like this:
    //  (Use the online tool at https://tools.chilkat.io/jsonParse.cshtml
    //  to generate JSON parsing code.)

    //  {
    //    "responseStatus": 0,
    //    "responseTypeOid": "1.3.6.1.5.5.7.48.1.1",
    //    "responseTypeName": "ocspBasic",
    //    "response": {
    //      "responderIdChoice": "KeyHash",
    //      "responderKeyHash": "d8K4UJpndnaxLcKG0IOgfqZ+uks=",
    //      "dateTime": "20180803193937Z",
    //      "cert": [
    //        {
    //          "hashOid": "1.3.14.3.2.26",
    //          "hashAlg": "SHA-1",
    //          "issuerNameHash": "9u2wY2IygZo19o11oJ0CShGqbK0=",
    //          "issuerKeyHash": "d8K4UJpndnaxLcKG0IOgfqZ+uks=",
    //          "serialNumber": "6175535D87BF94B6",
    //          "status": 0,
    //          "thisUpdate": "20180803193937Z",
    //          "nextUpdate": "20180810193937Z"
    //        }
    //      ]
    //    }
    //  }
    //  

    //  The certificate status:
    int certStatus = -1;
    if (jsonReply.HasMember("response.cert[0].status") == true) {
        certStatus = jsonReply.IntOf("response.cert[0].status");
    }

    //  Possible certStatus values are:
    //  -1: No status returned.
    //  0: Good
    //  1: Revoked
    //  2: Unknown.
    std::cout << "Certificate Status: " << certStatus << "\r\n";
    }