(VB.NET) Verify Authenticode Signature of EXE or DLL

See more Code Signing Examples

Demonstrates how to verify an Authenticode signed EXE or DLL.

Note: Chilkat's code signing class was added in v9.5.0.97

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Chilkat .NET Framework

Chilkat for .NET Core

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


' You can verify a signed DLL or EXE.
Dim path As String = "c:/someDir/something.dll"

' The verify method returns an overall indicator of whether
' the EXE or DLL can be trusted or not.
' The details of the signature are emitted to the JSON object
' passed in the last argument.

Dim json As New Chilkat.JsonObject
json.EmitCompact = False

Dim validator As New Chilkat.CodeSign
Dim valid As Boolean = validator.VerifySignature(path,json)
If (valid = False) Then
    ' Validation failed.
    Debug.WriteLine(validator.LastErrorText)
    ' You can also examine the details of the validation (see below)
    Debug.WriteLine(json.Emit())
    Exit Sub
End If


' Examine the details of the Authenticode signature
' println json.Emit();

' An example of the JSON details of an authenticode signature, with selected parsing code, is shown below.
' 
' Use this online tool to generate parsing code from sample JSON: 
' Generate Parsing Code from JSON


' {
'   "pkcs7": {
'     "verify": {
'       "peFile": {
'         "hashOid": "2.16.840.1.101.3.4.2.1",
'         "hash": "q9tzWEcea8f8kaMXG8LpWNPe9JIW7aKccYWuL3mrCBw="
'       },
'       "certs": [
'         {
'           "issuerCN": "AAA Certificate Services",
'           "serial": "48FC93B46055948D36A7C98A89D69416"
'         },
'         {
'           "issuerCN": "Sectigo Public Code Signing Root R46",
'           "serial": "621D6D0C52019E3B9079152089211C0A"
'         },
'         {
'           "issuerCN": "Sectigo Public Code Signing CA R36",
'           "serial": "3FF5B69109BFD4046C92CC0D18EE23C2"
'         }
'       ],
'       "digestAlgorithms": [
'         "sha256"
'       ],
'       "signerInfo": [
'         {
'           "cert": {
'             "serialNumber": "3FF5B69109BFD4046C92CC0D18EE23C2",
'             "issuerCN": "Sectigo Public Code Signing CA R36",
'             "digestAlgOid": "2.16.840.1.101.3.4.2.1",
'             "digestAlgName": "SHA256"
'           },
'           "contentType": "1.3.6.1.4.1.311.2.1.4",
'           "messageDigest": "4MkPVkY4qdwoVAj5JcCvn3ISSS5yqtf1+KmIs/Ckni4=",
'           "signingAlgOid": "1.2.840.113549.1.1.1",
'           "signingAlgName": "RSA-PKCSV-1_5",
'           "authAttr": {
'             "1.3.6.1.4.1.311.2.1.12": {
'               "der": "MAA="
'             },
'             "1.2.840.113549.1.9.3": {
'               "name": "contentType",
'               "oid": "1.3.6.1.4.1.311.2.1.4"
'             },
'             "1.3.6.1.4.1.311.2.1.11": {
'               "der": "MAwGCisGAQQBgjcCARU="
'             },
'             "1.2.840.113549.1.9.4": {
'               "name": "messageDigest",
'               "digest": "4MkPVkY4qdwoVAj5JcCvn3ISSS5yqtf1+KmIs/Ckni4="
'             }
'           },
'           "unauthAttr": {
'             "1.3.6.1.4.1.311.3.3.1": {
'               "name": "timestampToken",
'               "der": "MIIXJwY ... QZej",
'               "verify": {
'                 "digestAlgorithms": [
'                   "sha256"
'                 ],
'                 "signerInfo": [
'                   {
'                     "cert": {
'                       "serialNumber": "0544AFF3949D0839A6BFDB3F5FE56116",
'                       "issuerCN": "DigiCert Trusted G4 RSA4096 SHA256 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": "240117124047Z",
'                     "messageDigest": "y6cKjJoRfgJwW+Dj29w3tEfWqVybz7Sg+d8opKQxCjM=",
'                     "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": "240117124047Z"
'                       },
'                       "1.2.840.113549.1.9.16.2.12": {
'                         "name": "signingCertificate",
'                         "der": "MBowGDAWBBRm8CsywsLJD4JdzqqKycZPGZzPQA=="
'                       },
'                       "1.2.840.113549.1.9.4": {
'                         "name": "messageDigest",
'                         "digest": "y6cKjJoRfgJwW+Dj29w3tEfWqVybz7Sg+d8opKQxCjM="
'                       },
'                       "1.2.840.113549.1.9.16.2.47": {
'                         "name": "signingCertificateV2",
'                         "der": "MCYwJDAiBCDS9uRt7XQizNHUQFdoQTZvgoraVZquMxavTRqa1Ax4KA=="
'                       }
'                     }
'                   }
'                 ],
'                 "uncommonOptions": "NO_SIGCERTV2_OID,NoSigningCertV2IssuerSerial"
'               },
'               "timestampSignatureVerified": true,
'               "tstInfo": {
'                 "tsaPolicyId": "2.16.840.1.114412.7.1",
'                 "messageImprint": {
'                   "hashAlg": "sha256",
'                   "digest": "JqY7U+30qScMnRQwnDfUYEikZwOLHMhKX0oo5zo4ils=",
'                   "digestMatches": true
'                 },
'                 "serialNumber": "6E4597E574BC909213565DAEBC0E4888",
'                 "genTime": "20240117124047Z"
'               }
'             }
'           }
'         }
'       ],
'       "pkcs7": {
'         "verify": {
'           "certs": [
'             {
'               "issuerCN": "DigiCert Trusted G4 RSA4096 SHA256 TimeStamping CA",
'               "serial": "0544AFF3949D0839A6BFDB3F5FE56116"
'             },
'             {
'               "issuerCN": "DigiCert Trusted Root G4",
'               "serial": "073637B724547CD847ACFD28662A5E5B"
'             },
'             {
'               "issuerCN": "DigiCert Assured ID Root CA",
'               "serial": "0E9B188EF9D02DE7EFDB50E20840185A"
'             }
'           ]
'         }
'       }
'     }
'   }
' }

Dim issuerCN As String
Dim serial As String
Dim genTime As New Chilkat.DtObj
Dim dt As New Chilkat.CkDateTime

' Show the certificates embedded in the PKCS7 signature.
Debug.WriteLine("Certificates contained in the PKCS7 signature:")
Dim i As Integer = 0
Dim count_i As Integer = json.SizeOfArray("pkcs7.verify.certs")
While i < count_i
    json.I = i
    issuerCN = json.StringOf("pkcs7.verify.certs[i].issuerCN")
    serial = json.StringOf("pkcs7.verify.certs[i].serial")
    Debug.WriteLine(issuerCN & ", " & serial)
    i = i + 1
End While

' Show details about the signing certificate(s)
Dim numSigners As Integer = json.SizeOfArray("pkcs7.verify.signerInfo")
i = 0
While i < numSigners
    json.I = i
    Debug.WriteLine("---- Signing Certificate ----")
    Debug.WriteLine("serial number: " & json.StringOf("pkcs7.verify.signerInfo[i].cert.serialNumber"))
    Debug.WriteLine("issuerCN: " & json.StringOf("pkcs7.verify.signerInfo[i].cert.issuerCN"))
    Debug.WriteLine("hash algorithm: " & json.StringOf("pkcs7.verify.signerInfo[i].cert.digestAlgName"))
    Debug.WriteLine("signing algorithm: " & json.StringOf("pkcs7.verify.signerInfo[i].signingAlgName"))

    ' If this signature includes a timestamp token, get information about it.
    If (json.HasMember("pkcs7.verify.signerInfo[i].unauthAttr.""1.3.6.1.4.1.311.3.3.1""") = True) Then
        ' We're going to assume the timestamp token had only 1 signer..
        Debug.WriteLine("--- Timestamp Token ----")
        Debug.WriteLine("TS hash algorithm: " & json.StringOf("pkcs7.verify.signerInfo[i].unauthAttr.""1.3.6.1.4.1.311.3.3.1"".verify.digestAlgorithms[0]"))
        Debug.WriteLine("TS certificate serial: " & json.StringOf("pkcs7.verify.signerInfo[i].unauthAttr.""1.3.6.1.4.1.311.3.3.1"".verify.signerInfo[0].cert.serialNumber"))
        Debug.WriteLine("TS certificate issuerCN: " & json.StringOf("pkcs7.verify.signerInfo[i].unauthAttr.""1.3.6.1.4.1.311.3.3.1"".verify.signerInfo[0].cert.issuerCN"))
        Debug.WriteLine("timestamp signature verified: " & json.BoolOf("pkcs7.verify.signerInfo[i].unauthAttr.""1.3.6.1.4.1.311.3.3.1"".timestampSignatureVerified"))
        json.DtOf("pkcs7.verify.signerInfo[i].unauthAttr.""1.3.6.1.4.1.311.3.3.1"".tstInfo.genTime",False,genTime)
        dt.SetFromDtObj(genTime)
        Debug.WriteLine("timestamp date/time: " & dt.GetAsRfc822(True))
    End If


    i = i + 1
End While

Debug.WriteLine("The Authenticode signature is valid.")

' Sample output:

' Certificates contained in the PKCS7 signature:
' AAA Certificate Services, 48FC93B46055948D36A7C98A89D69416
' Sectigo Public Code Signing Root R46, 621D6D0C52019E3B9079152089211C0A
' Sectigo Public Code Signing CA R36, 3FF5B69109BFD4046C92CC0D18EE23C2
' ---- Signing Certificate ----
' serial number: 3FF5B69109BFD4046C92CC0D18EE23C2
' issuerCN: Sectigo Public Code Signing CA R36
' hash algorithm: SHA256
' signing algorithm: RSA-PKCSV-1_5
' --- Timestamp Token ----
' TS hash algorithm: sha256
' TS certificate serial: 0544AFF3949D0839A6BFDB3F5FE56116
' TS certificate issuerCN: DigiCert Trusted G4 RSA4096 SHA256 TimeStamping CA
' timestamp signature verified: True
' timestamp date/time: Wed, 17 Jan 2024 06:40:47 -0600
' The Authenticode signature is valid.