Perl 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. Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

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

my $crypt = Chilkat2::Crypt2->new;

my $inFile = 'qa_data/p7m/brainpoolP256r1.p7m';
my $outFile = 'qa_output/something.dat';

# Verify and extract the signed data.
my $success = $crypt->VerifyP7M($inFile, $outFile);
if (!$success) {
    print $crypt->LastErrorText, "\n";
    exit;
}

# Examine details about the signature(s)
my $json = Chilkat2::JsonObject->new;
$crypt->GetLastJsonData($json);
$json->EmitCompact(0);
print $json->Emit(), "\n";

# 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...
my $strVal = '';
my $certSerialNumber = '';
my $certIssuerCN = '';
my $certIssuerDN = '';
my $certDigestAlgOid = '';
my $certDigestAlgName = '';
my $contentType = '';
my $signingTime = '';
my $messageDigest = '';
my $signingAlgOid = '';
my $signerDigest = '';
my $j = 0;
my $count_j = 0;
my $oid = '';
my $oidName = '';
my $der = '';

my $i = 0;
my $count_i = $json->SizeOfArray('pkcs7.verify.digestAlgorithms');
while ($i < $count_i) {
    $json->I($i);
    $strVal = $json->StringOf('pkcs7.verify.digestAlgorithms[i]');
    $i = $i + 1;
}

$i = 0;
$count_i = $json->SizeOfArray('pkcs7.verify.signerInfo');
while ($i < $count_i) {
    $json->I($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) {
        $json->J($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!\n";