CkPython Requires Chilkat v11.0.0+

Verify a .p7m and get Algorithm Information

See more Digital Signatures Examples

Demonstrates how to verify a .p7m and then examine the algorithms used by the signature. CkPython

import sys
import chilkat

success = False

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

crypt = chilkat.CkCrypt2()

inFile = "qa_data/p7m/brainpoolP256r1.p7m"
outFile = "qa_output/something.dat"

#  Verify and extract the signed data.
success = crypt.VerifyP7M(inFile,outFile)
if (success == False):
    print(crypt.lastErrorText())
    sys.exit()

#  Examine details about the signature(s)
json = chilkat.CkJsonObject()
crypt.GetLastJsonData(json)
json.put_EmitCompact(False)
print(json.emit())

#  Sample output

#  {
#    "pkcs7": {
#      "verify": {
#        "digestAlgorithms": [
#          "sha256"
#        ],
#        "signerInfo": [
#          {
#            "cert": {
#              "serialNumber": "FFFFE552B302FFFFFF1E34C3ACEB2FFFF",
#              "issuerCN": "The common name of the cert...",
#              "issuerDN": "",
#              "digestAlgOid": "2.16.840.1.101.3.4.2.1",
#              "digestAlgName": "SHA256"
#            },
#            "contentType": "1.2.840.113549.1.7.1",
#            "signingTime": "190409140500Z",
#            "messageDigest": "lQe9If7vZKFf/NlSYu5Esmlw3phVK/RFsbbb1uH73t8=",
#            "signingAlgOid": "1.2.840.10045.4.3.2",
#            "signerDigest": "lQe9If7vZKFf/NlSYu5Esmlw3phVK/RFsbbb1uH73t8=",
#            "authAttr": [
#              {
#                "oid": "1.2.840.113549.1.9.3",
#                "oidName": "contentType"
#              },
#              {
#                "oid": "1.2.840.113549.1.9.5",
#                "oidName": "signingTime"
#              },
#              {
#                "oid": "1.2.840.113549.1.9.52",
#                "oidName": "1.2.840.113549.1.9.52",
#                "der": "MBs ... AwI="
#              },
#              {
#                "oid": "1.2.840.113549.1.9.4",
#                "oidName": "messageDigest"
#              },
#              {
#                "oid": "1.2.840.113549.1.9.16.2.47",
#                "oidName": "signingCertificateV2",
#                "der": "MCYw .. 7PlQ=="
#              },
#              {
#                "oid": "1.2.840.113549.1.9.20",
#                "oidName": "1.2.840.113549.1.9.20"
#              }
#            ]
#          }
#        ]
#      }
#    }
#  }

#  Code for parsing the above JSON...

i = 0
count_i = json.SizeOfArray("pkcs7.verify.digestAlgorithms")
while i < count_i :
    json.put_I(i)
    strVal = json.stringOf("pkcs7.verify.digestAlgorithms[i]")
    i = i + 1

i = 0
count_i = json.SizeOfArray("pkcs7.verify.signerInfo")
while i < count_i :
    json.put_I(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")
    messageDigest = json.stringOf("pkcs7.verify.signerInfo[i].messageDigest")
    signingAlgOid = json.stringOf("pkcs7.verify.signerInfo[i].signingAlgOid")
    signerDigest = json.stringOf("pkcs7.verify.signerInfo[i].signerDigest")
    j = 0
    count_j = json.SizeOfArray("pkcs7.verify.signerInfo[i].authAttr")
    while j < count_j :
        json.put_J(j)
        oid = json.stringOf("pkcs7.verify.signerInfo[i].authAttr[j].oid")
        oidName = json.stringOf("pkcs7.verify.signerInfo[i].authAttr[j].oidName")
        der = json.stringOf("pkcs7.verify.signerInfo[i].authAttr[j].der")
        j = j + 1

    i = i + 1

print("Success!")