Classic ASP Requires Chilkat v11.0.0+
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 Classic ASP Downloads

Classic ASP
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<body>
<%
success = 0

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

set crypt = Server.CreateObject("Chilkat.Crypt2")

outputFile = "qa_output/original.xml"
inFile = "qa_data/p7m/fattura_signature.xml.p7m"

'  Verify the signature and extract the contained file, which in this case is XML.
success = crypt.VerifyP7M(inFile,outputFile)
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( crypt.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Signature validated.") & "</pre>"

'  Now let's examine the information about the signature.
set json = Server.CreateObject("Chilkat.JsonObject")
crypt.GetLastJsonData json

json.EmitCompact = 0
Response.Write "<pre>" & Server.HTMLEncode( json.Emit()) & "</pre>"

'  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

set authAttrSigningTimeUtctime = Server.CreateObject("Chilkat.DtObj")

i = 0
count_i = json.SizeOfArray("pkcs7.verify.certs")
Do While i < count_i
    json.I = i
    issuerCN = json.StringOf("pkcs7.verify.certs[i].issuerCN")
    serial = json.StringOf("pkcs7.verify.certs[i].serial")
    i = i + 1
Loop
i = 0
count_i = json.SizeOfArray("pkcs7.verify.digestAlgorithms")
Do While i < count_i
    json.I = i
    strVal = json.StringOf("pkcs7.verify.digestAlgorithms[i]")
    i = i + 1
Loop
i = 0
count_i = json.SizeOfArray("pkcs7.verify.signerInfo")
Do While i < count_i
    json.I = i
    certSubjectKeyIdentifier = json.StringOf("pkcs7.verify.signerInfo[i].cert.subjectKeyIdentifier")
    certDigestAlgOid = json.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgOid")
    certDigestAlgName = json.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgName")
    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")
    success = json.DtOf("pkcs7.verify.signerInfo[i].authAttr.""1.2.840.113549.1.9.5"".utctime",0,authAttrSigningTimeUtctime)
    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")
    authAttrSigningCertificateV2Name = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.""1.2.840.113549.1.9.16.2.47"".name")
    authAttrSigningCertificateV2Der = json.StringOf("pkcs7.verify.signerInfo[i].authAttr.""1.2.840.113549.1.9.16.2.47"".der")
    i = i + 1
Loop

%>
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