Tcl

Verify a CAdES-BES Signature and Examine Signature Contents

See more Digital Signatures Examples

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

load ./chilkat.dll

set success 0

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

set crypt [new_CkCrypt2]

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

# Verify the signature and extract the contained file, which in this case is XML.
set success [CkCrypt2_VerifyP7M $crypt $inFile $outputFile]
if {$success == 0} then {
    puts [CkCrypt2_lastErrorText $crypt]
    delete_CkCrypt2 $crypt
    exit
}

puts "Signature validated."

# Now let's examine the information about the signature.
set json [new_CkJsonObject]

CkCrypt2_GetLastJsonData $crypt $json

CkJsonObject_put_EmitCompact $json 0
puts [CkJsonObject_emit $json]

# 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 [new_CkDtObj]

set i 0
set count_i [CkJsonObject_SizeOfArray $json "pkcs7.verify.certs"]
while {$i < $count_i} {
    CkJsonObject_put_I $json $i
    set issuerCN [CkJsonObject_stringOf $json "pkcs7.verify.certs[i].issuerCN"]
    set serial [CkJsonObject_stringOf $json "pkcs7.verify.certs[i].serial"]
    set i [expr $i + 1]
}
set i 0
set count_i [CkJsonObject_SizeOfArray $json "pkcs7.verify.digestAlgorithms"]
while {$i < $count_i} {
    CkJsonObject_put_I $json $i
    set strVal [CkJsonObject_stringOf $json "pkcs7.verify.digestAlgorithms[i]"]
    set i [expr $i + 1]
}
set i 0
set count_i [CkJsonObject_SizeOfArray $json "pkcs7.verify.signerInfo"]
while {$i < $count_i} {
    CkJsonObject_put_I $json $i
    set certSubjectKeyIdentifier [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].cert.subjectKeyIdentifier"]
    set certDigestAlgOid [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].cert.digestAlgOid"]
    set certDigestAlgName [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].cert.digestAlgName"]
    set signingAlgOid [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].signingAlgOid"]
    set signingAlgName [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].signingAlgName"]
    set authAttrContentTypeName [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".name"]
    set authAttrContentTypeOid [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.3\".oid"]
    set authAttrSigningTimeName [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".name"]
    CkJsonObject_DtOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".utctime" 0 $authAttrSigningTimeUtctime
    set authAttrMessageDigestName [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".name"]
    set authAttrMessageDigestDigest [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.4\".digest"]
    set authAttrSigningCertificateV2Name [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.16.2.47\".name"]
    set authAttrSigningCertificateV2Der [CkJsonObject_stringOf $json "pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.16.2.47\".der"]
    set i [expr $i + 1]
}

delete_CkCrypt2 $crypt
delete_CkJsonObject $json
delete_CkDtObj $authAttrSigningTimeUtctime