(Go) RFC3161 Timestamp Client - Fetch from Timestamp Authority (TSA) and Verify

Sends an RFC 3161 timestamp request to a TSA (Timestamp Authority) server and validates the timestamp token response.

Note: This example requires Chilkat v9.5.0.75 or greater.

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    // Note: Requires Chilkat v9.5.0.75 or greater.

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

    // First sha-256 hash the data that is to be timestamped.
    // In this example, the data is the string "Hello World"
    var success bool
    crypt := chilkat.NewCrypt2()
    crypt.SetHashAlgorithm("sha256")
    crypt.SetEncodingMode("base64")
    base64Hash := crypt.HashStringENC("Hello World")

    http := chilkat.NewHttp()

    requestToken := chilkat.NewBinData()
    optionalPolicyOid := ""
    addNonce := false
    requestTsaCert := true

    // Create a time-stamp request token
    success = http.CreateTimestampRequest("sha256",*base64Hash,optionalPolicyOid,addNonce,requestTsaCert,requestToken)
    if success != true {
        fmt.Println(http.LastErrorText())
        crypt.DisposeCrypt2()
        http.DisposeHttp()
        requestToken.DisposeBinData()
        return
    }

    // Send the time-stamp request token to the TSA.
    // This is the equivalent of the following CURL command:
    // curl -H "Content-Type: application/timestamp-query" --data-binary '@file.tsq' https://freetsa.org/tsr > file.tsr
    tsaUrl := "https://freetsa.org/tsr"
    // Another timestamp server you could try is: http://timestamp.digicert.com
    tsaUrl = "http://timestamp.digicert.com"
    resp := http.PBinaryBd("POST",tsaUrl,requestToken,"application/timestamp-query",false,false)
    if http.LastMethodSuccess() != true {
        fmt.Println(http.LastErrorText())
        crypt.DisposeCrypt2()
        http.DisposeHttp()
        requestToken.DisposeBinData()
        return
    }

    // Get the timestamp reply from the HTTP response object.
    timestampReply := chilkat.NewBinData()
    resp.GetBodyBd(timestampReply)
    resp.DisposeHttpResponse()

    // Show the base64 encoded timestamp reply.
    fmt.Println(*timestampReply.GetEncoded("base64"))

    // Let's verify the timestamp reply against the TSA's cert, which we've previously downloaded.
    // See https://freetsa.org/index_en.php
    tsaCert := chilkat.NewCert()
    success = tsaCert.LoadFromFile("qa_data/certs/freetsa.org.cer")
    if success != true {
        fmt.Println(tsaCert.LastErrorText())
        crypt.DisposeCrypt2()
        http.DisposeHttp()
        requestToken.DisposeBinData()
        timestampReply.DisposeBinData()
        tsaCert.DisposeCert()
        return
    }

    // The VerifyTimestampReply method will return one of the following values:
    // -1:  The timestampReply does not contain a valid timestamp reply.
    // -2: The  timestampReply is a valid timestamp reply, but failed verification using the public key of the tsaCert.
    // 0:  Granted and verified.
    // 1: Granted and verified, with mods (see RFC 3161)
    // 2: Rejected.
    // 3: Waiting.
    // 4: Revocation Warning
    // 5: Revocation Notification
    pkiStatus := http.VerifyTimestampReply(timestampReply,tsaCert)
    if pkiStatus < 0 {
        fmt.Println(http.LastErrorText())
        crypt.DisposeCrypt2()
        http.DisposeHttp()
        requestToken.DisposeBinData()
        timestampReply.DisposeBinData()
        tsaCert.DisposeCert()
        return
    }

    fmt.Println("pkiStatus = ", pkiStatus)

    json := http.LastJsonData()
    json.SetEmitCompact(false)
    fmt.Println(*json.Emit())

    // The LastJsonData looks like the following.
    // Note: The "timestampReply.pkiStatus" portion of the LastJsonData was added in Chilkat v9.5.0.83

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    // {
    //   "timestampReply": {
    //     "pkiStatus": {
    //       "value": 0,
    //       "meaning": "granted"
    //     }
    //   },
    //   "pkcs7": {
    //     "verify": {
    //       "digestAlgorithms": [
    //         "sha256"
    //       ],
    //       "signerInfo": [
    //         {
    //           "cert": {
    //             "serialNumber": "04CD3F8568AE76C61BB0FE7160CCA76D",
    //             "issuerCN": "DigiCert SHA2 Assured ID Timestamping CA",
    //             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
    //             "digestAlgName": "SHA256"
    //           },
    //           "contentType": "1.2.840.113549.1.9.16.1.4",
    //           "signingTime": "200405023019Z",
    //           "messageDigest": "f14zOsdnN9vyyV3HjjBiLzNDi1PF28hAFMODxNkNRZs=",
    //           "signingAlgOid": "1.2.840.113549.1.1.1",
    //           "signingAlgName": "RSA-PKCSV-1_5",
    //           "authAttr": {
    //             "1.2.840.113549.1.9.3": {
    //               "name": "contentType",
    //               "oid": "1.2.840.113549.1.9.16.1.4"
    //             },
    //             "1.2.840.113549.1.9.5": {
    //               "name": "signingTime",
    //               "utctime": "200405023019Z"
    //             },
    //             "1.2.840.113549.1.9.16.2.12": {
    //               "name": "signingCertificate",
    //               "der": "MBowGDAWBBQDJb1QXtqWMC3CL0+gHkwovig0xQ=="
    //             },
    //             "1.2.840.113549.1.9.4": {
    //               "name": "messageDigest",
    //               "digest": "f14zOsdnN9vyyV3HjjBiLzNDi1PF28hAFMODxNkNRZs="
    //             }
    //           }
    //         }
    //       ]
    //     }
    //   }
    // }

    signingTime := chilkat.NewDtObj()
    authAttrSigningTimeUtctime := chilkat.NewDtObj()
    var strVal *string = new(string)
    var certSerialNumber *string = new(string)
    var certIssuerCN *string = new(string)
    var certDigestAlgOid *string = new(string)
    var certDigestAlgName *string = new(string)
    var contentType *string = new(string)
    var messageDigest *string = new(string)
    var signingAlgOid *string = new(string)
    var signingAlgName *string = new(string)
    var authAttrContentTypeName *string = new(string)
    var authAttrContentTypeOid *string = new(string)
    var authAttrSigningTimeName *string = new(string)
    var authAttrSigningCertificateName *string = new(string)
    var authAttrSigningCertificateDer *string = new(string)
    var authAttrMessageDigestName *string = new(string)
    var authAttrMessageDigestDigest *string = new(string)

    timestampReplyPkiStatusValue := json.IntOf("timestampReply.pkiStatus.value")
    timestampReplyPkiStatusMeaning := json.StringOf("timestampReply.pkiStatus.meaning")
    i := 0
    count_i := json.SizeOfArray("pkcs7.verify.digestAlgorithms")
    for i < count_i {
        json.SetI(i)
        strVal = json.StringOf("pkcs7.verify.digestAlgorithms[i]")
        i = i + 1
    }

    i = 0
    count_i = json.SizeOfArray("pkcs7.verify.signerInfo")
    for i < count_i {
        json.SetI(i)
        certSerialNumber = json.StringOf("pkcs7.verify.signerInfo[i].cert.serialNumber")
        certIssuerCN = json.StringOf("pkcs7.verify.signerInfo[i].cert.issuerCN")
        certDigestAlgOid = json.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgOid")
        certDigestAlgName = json.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgName")
        contentType = json.StringOf("pkcs7.verify.signerInfo[i].contentType")
        json.DtOf("pkcs7.verify.signerInfo[i].signingTime",false,signingTime)
        messageDigest = json.StringOf("pkcs7.verify.signerInfo[i].messageDigest")
        signingAlgOid = json.StringOf("pkcs7.verify.signerInfo[i].signingAlgOid")
        signingAlgName = json.StringOf("pkcs7.verify.signerInfo[i].signingAlgName")
        authAttrContentTypeName = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".name")
        authAttrContentTypeOid = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".oid")
        authAttrSigningTimeName = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".name")
        json.DtOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".utctime",false,authAttrSigningTimeUtctime)
        authAttrSigningCertificateName = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.16.2.12\".name")
        authAttrSigningCertificateDer = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.16.2.12\".der")
        authAttrMessageDigestName = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".name")
        authAttrMessageDigestDigest = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".digest")
        i = i + 1
    }

    json.DisposeJsonObject()

    crypt.DisposeCrypt2()
    http.DisposeHttp()
    requestToken.DisposeBinData()
    timestampReply.DisposeBinData()
    tsaCert.DisposeCert()
    signingTime.DisposeDtObj()
    authAttrSigningTimeUtctime.DisposeDtObj()