(Lianja) Verify a CAdES-BES Signature and Examine Signature Contents

Demonstrates how to validate a .p7m (.p7s) signature and examine the contents of the signature.

Chilkat Lianja Extension Download Chilkat Lianja Extension

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

loCrypt = createobject("CkCrypt2")

lcOutputFile = "qa_output/original.xml"
lcInFile = "qa_data/p7m/fattura_signature.xml.p7m"

// Verify the signature and extract the contained file, which in this case is XML.
llSuccess = loCrypt.VerifyP7M(lcInFile,lcOutputFile)
if (llSuccess = .F.) then
    ? loCrypt.LastErrorText
    release loCrypt
    return
endif

? "Signature validated."

// Now let's examine the information about the signature.
loJson = loCrypt.LastJsonData()
if (loCrypt.LastMethodSuccess = .F.) then
    // This should never be the case...
    ? "No information available."
    release loCrypt
    return
endif

loJson.EmitCompact = .F.
? loJson.Emit()

// Here's an example of the information about the signature:
// {
//   "pkcs7": {
//     "verify": {
//       "certs": [
//         {
//           "issuerCN": "Xyz EU Qualified Certificates CA G1",
//           "serial": "99A28A51AC389999"
//         }
//       ],
//       "useConstructedOctets": true,
//       "digestAlgorithms": [
//         "sha256"
//       ],
//       "signerInfo": [
//         {
//           "cert": {
//             "subjectKeyIdentifier": "5VM4x8AWnXf07yzbXuLtbb0U3yY=",
//             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
//             "digestAlgName": "SHA256"
//           },
//           "signingAlgOid": "1.2.840.113549.1.1.11",
//           "signingAlgName": "RSA-SHA256-PKCSV-1_5",
//           "authAttr": {
//             "1.2.840.113549.1.9.3": {
//               "name": "contentType",
//               "oid": "1.2.840.113549.1.7.1"
//             },
//             "1.2.840.113549.1.9.5": {
//               "name": "signingTime",
//               "utctime": "190901152340Z"
//             },
//             "1.2.840.113549.1.9.4": {
//               "name": "messageDigest",
//               "digest": "y+gd/zAQK33A//HInhaZba7w1fUJleV9AHbP1Ntx6U0="
//             },
//             "1.2.840.113549.1.9.16.2.47": {
//               "name": "signingCertificateV2",
//               "der": "MIH4MI..w4vv0="
//             }
//           }
//         }
//       ]
//     }
//   }
// }

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

loAuthAttrSigningTimeUtctime = createobject("CkDtObj")

i = 0
lnCount_i = loJson.SizeOfArray("pkcs7.verify.certs")
do while i < lnCount_i
    loJson.I = i
    lcIssuerCN = loJson.StringOf("pkcs7.verify.certs[i].issuerCN")
    lcSerial = loJson.StringOf("pkcs7.verify.certs[i].serial")
    i = i + 1
enddo
i = 0
lnCount_i = loJson.SizeOfArray("pkcs7.verify.digestAlgorithms")
do while i < lnCount_i
    loJson.I = i
    lcStrVal = loJson.StringOf("pkcs7.verify.digestAlgorithms[i]")
    i = i + 1
enddo
i = 0
lnCount_i = loJson.SizeOfArray("pkcs7.verify.signerInfo")
do while i < lnCount_i
    loJson.I = i
    lcCertSubjectKeyIdentifier = loJson.StringOf("pkcs7.verify.signerInfo[i].cert.subjectKeyIdentifier")
    lcCertDigestAlgOid = loJson.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgOid")
    lcCertDigestAlgName = loJson.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgName")
    lcSigningAlgOid = loJson.StringOf("pkcs7.verify.signerInfo[i].signingAlgOid")
    lcSigningAlgName = loJson.StringOf("pkcs7.verify.signerInfo[i].signingAlgName")
    lcAuthAttrContentTypeName = loJson.StringOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.3".name')
    lcAuthAttrContentTypeOid = loJson.StringOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.3".oid')
    lcAuthAttrSigningTimeName = loJson.StringOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.5".name')
    loJson.DtOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.5".utctime',.F.,loAuthAttrSigningTimeUtctime)
    lcAuthAttrMessageDigestName = loJson.StringOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.4".name')
    lcAuthAttrMessageDigestDigest = loJson.StringOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.4".digest')
    lcAuthAttrSigningCertificateV2Name = loJson.StringOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.16.2.47".name')
    lcAuthAttrSigningCertificateV2Der = loJson.StringOf('pkcs7.verify.signerInfo[i].authAttr."1.2.840.113549.1.9.16.2.47".der')
    i = i + 1
enddo

release loJson


release loCrypt
release loAuthAttrSigningTimeUtctime