(Perl) Verify and Unwrap S/MIME, and get Information about CMS Signature

Demonstrates calling the Verify method to verify and unwrap S/MIME. The MIME is restored to the original structure that it would have originally had prior to signing. The Verify method works with both detached signatures, as well as opaque/attached signatures.

Calls LastJsonData to get information about the signature(s) that were verified.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

$mime = chilkat::CkMime->new();

# Load the signed MIME from a file...
$success = $mime->LoadMimeFile("qa_data/mime/detached_sig.eml");
if ($success == 0) {
    print $mime->lastErrorText() . "\r\n";
    exit;
}

# Verify the S/MIME and restore the MIME
# to the structure/content it had prior to signing.
$verified = $mime->Verify();
if ($verified == 0) {
    print $mime->lastErrorText() . "\r\n";
    exit;
}

# Examine the details of what was verified.
# json is a JsonObject
$json = $mime->LastJsonData();
$json->put_EmitCompact(0);
print $json->emit() . "\r\n";

# The code to parse the following JSON (i.e. extract desired information) is shown below..

# {
#   "pkcs7": {
#     "verify": {
#       "certs": [
#         {
#           "issuerCN": "VeriSign Class 1 Public Primary Certification Authority - G3",
#           "serial": "0702A21A85B84B659E180A6EE6F5A365"
#         },
#         {
#           "issuerCN": "VeriSign Class 1 Public Primary Certification Authority - G3",
#           "serial": "008B5B75568454850B00CFAF3848CEB1A4"
#         },
#         {
#           "issuerCN": "Symantec Class 1 Individual Subscriber CA - G5",
#           "serial": "619C55C32FF6BD1A7B7E0330D21C8F3C"
#         }
#       ],
#       "digestAlgorithms": [
#         "sha1"
#       ],
#       "signerInfo": [
#         {
#           "cert": {
#             "serialNumber": "619C55C32FF6BD1A7B7E0330D21C8F3C",
#             "issuerCN": "Symantec Class 1 Individual Subscriber CA - G5",
#             "digestAlgOid": "1.3.14.3.2.26",
#             "digestAlgName": "SHA1"
#           },
#           "contentType": "1.2.840.113549.1.7.1",
#           "signingTime": "160428055000Z",
#           "messageDigest": "2hJJVmO/jtaJV5uCKMFzIkRRvtY=",
#           "signingAlgOid": "1.2.840.113549.1.1.1",
#           "signingAlgName": "RSA-PKCSV-1_5",
#           "authAttr": {
#             "1.2.840.113549.1.9.3": {
#               "name": "contentType",
#               "oid": "1.2.840.113549.1.7.1"
#             },
#             "1.2.840.113549.1.9.5": {
#               "name": "signingTime",
#               "utctime": "160428055000Z"
#             },
#             "1.2.840.113549.1.9.4": {
#               "name": "messageDigest",
#               "digest": "2hJJVmO/jtaJV5uCKMFzIkRRvtY="
#             },
#             "1.2.840.113549.1.9.15": {
#               "der": "MFAwCwYJYIZIAWUDBAECMAoGCCqGSIb3DQMHMA4GCCqGSIb3DQMCAgIAgDANBggqhkiG9w0DAgIBQDAHBgUrDgMCBzANBggqhkiG9w0DAgIBKA=="
#             },
#             "1.3.6.1.4.1.311.16.4": {
#               "der": "MIG7MIG...7fgMw0hyPPA=="
#             }
#           }
#         }
#       ]
#     }
#   }
# }

# Use this online tool to generate parsing code from sample JSON: 
# Generate Parsing Code from JSON

$signingTime = chilkat::CkDtObj->new();
$authAttrSigningTimeUtctime = chilkat::CkDtObj->new();

$i = 0;
$count_i = $json->SizeOfArray("pkcs7.verify.certs");
while ($i < $count_i) {
    $json->put_I($i);
    $issuerCN = $json->stringOf("pkcs7.verify.certs[i].issuerCN");
    $serial = $json->stringOf("pkcs7.verify.certs[i].serial");
    $i = $i + 1;
}

$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");
    $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");
    $json->DtOf("pkcs7.verify.signerInfo[i].signingTime",0,$signingTime);
    $messageDigest = $json->stringOf("pkcs7.verify.signerInfo[i].messageDigest");
    $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");
    $json->DtOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.5\".utctime",0,$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");
    $authAttr1_2_840_113549_1_9_15Der = $json->stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.2.840.113549.1.9.15\".der");
    $authAttr1_3_6_1_4_1_311_16_4Der = $json->stringOf("pkcs7.verify.signerInfo[i].authAttr.\"1.3.6.1.4.1.311.16.4\".der");
    $i = $i + 1;
}