(Go) P7S - Access Signature Information (date/time, certificate used, etc.)

Examine a PKCS7 signature (.p7s) and get information about it. Note: This example requires Chilkat v9.5.0.75 or greater.

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

    // First load the .p7s file into a BinData object..
    bd := chilkat.NewBinData()
    success := bd.LoadFile("qa_data/p7s/sample.p7s")
    if success != true {
        fmt.Println("Failed to load .p7s file.")
        bd.DisposeBinData()
        return
    }

    // IMPORTANT:  This example requires Chilkat v9.5.0.75 or greater.
    crypt := chilkat.NewCrypt2()

    // Assuming this is a signature that contains the original data that was signed..
    success = crypt.OpaqueVerifyBd(bd)
    if success != true {
        fmt.Println(crypt.LastErrorText())
        bd.DisposeBinData()
        crypt.DisposeCrypt2()
        return
    }

    // Examine the LastJsonData after signature verification..
    json := crypt.LastJsonData()
    json.SetEmitCompact(false)
    fmt.Println(*json.Emit())

    // --
    // IMPORTANT:  This example requires Chilkat v9.5.0.75 or greater.
    // --

    // Sample output...
    // Go to http://tools.chilkat.io/jsonParse.cshtml
    // and paste the JSON into the online form to generate JSON parsing code.

    // {
    //   "pkcs7": {
    //     "verify": {
    //       "digestAlgorithms": [
    //         "sha256"
    //       ],
    //       "signerInfo": [
    //         {
    //           "cert": {
    //             "serialNumber": "AAC5FC48C0FD8FBB",
    //             "issuerCN": "AC ABCDEF RFB v5",
    //             "issuerDN": "",
    //             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
    //             "digestAlgName": "SHA-256"
    //           },
    //           "contentType": "1.2.840.113549.1.7.1",
    //           "signingTime": "180607195054Z",
    //           "messageDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8=",
    //           "signingAlgOid": "1.2.840.113549.1.1.11",
    //           "signerDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8="
    //         },
    //         {
    //           "cert": {
    //             "serialNumber": "324FB38ABD59723F",
    //             "issuerCN": "AC ABCDEF RFB v5",
    //             "issuerDN": "",
    //             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
    //             "digestAlgName": "SHA-256"
    //           },
    //           "contentType": "1.2.840.113549.1.7.1",
    //           "signingTime": "180608182517Z",
    //           "messageDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8=",
    //           "signingAlgOid": "1.2.840.113549.1.1.11",
    //           "signerDigest": "trzyxXbZ96z2M4mncyZ7BNMV4yIT92+5sS27Fu64iG8="
    //         }
    //       ]
    //     }
    //   }
    // }
    // 

    var i int
    var count_i int
    var strVal *string = new(string)
    var certSerialNumber *string = new(string)
    var certIssuerCN *string = new(string)
    var certIssuerDN *string = new(string)
    var certDigestAlgOid *string = new(string)
    var certDigestAlgName *string = new(string)
    var contentType *string = new(string)
    var signingTime *string = new(string)
    var messageDigest *string = new(string)
    var signingAlgOid *string = new(string)
    var signerDigest *string = new(string)
    dt := chilkat.NewCkDateTime()

    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")
        certIssuerDN = json.StringOf("pkcs7.verify.signerInfo[i].cert.issuerDN")
        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")
        signingTime = json.StringOf("pkcs7.verify.signerInfo[i].signingTime")

        // The signingTime isin UTCTime format.
        // UTCTime values take the form of either "YYMMDDhhmm[ss]Z" or "YYMMDDhhmm[ss](+|-)hhmm"
        // Starting in Chilkat v9.5.0.77, the SetFromTimestamp method auto-recognizes the UTCTime format and parses it correctly.
        success = dt.SetFromTimestamp(*signingTime)
        // To get the signingTime in other date/time formats, look at the online reference documentation for CkDateTime.
        // There are numerous methods such as GetAsDateTime, GetAsIso8601, GetAsUnixTime, GetAsRfc822, etc.

        messageDigest = json.StringOf("pkcs7.verify.signerInfo[i].messageDigest")
        signingAlgOid = json.StringOf("pkcs7.verify.signerInfo[i].signingAlgOid")
        signerDigest = json.StringOf("pkcs7.verify.signerInfo[i].signerDigest")
        i = i + 1
    }

    json.DisposeJsonObject()

    // println crypt.LastErrorText;
    fmt.Println("Success.")

    bd.DisposeBinData()
    crypt.DisposeCrypt2()
    dt.DisposeCkDateTime()