Lua 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. Lua

local chilkat = require("chilkat")

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

local crypt = chilkat.Crypt2.new()

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

-- Verify and extract the signed data.
local success = crypt:verify_p7_m(inFile, outFile)
if not success then
    print(crypt.last_error_text)
    return
end

-- Examine details about the signature(s)
local json = chilkat.JsonObject.new()
crypt:get_last_json_data(json)
json.emit_compact = 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...
local strVal = ""
local certSerialNumber = ""
local certIssuerCN = ""
local certIssuerDN = ""
local certDigestAlgOid = ""
local certDigestAlgName = ""
local contentType = ""
local signingTime = ""
local messageDigest = ""
local signingAlgOid = ""
local signerDigest = ""
local j = 0
local count_j = 0
local oid = ""
local oidName = ""
local der = ""

local i = 0
local count_i = json:size_of_array("pkcs7.verify.digestAlgorithms")
while i < count_i do
    json.i = i
    strVal = json:string_of("pkcs7.verify.digestAlgorithms[i]")
    i = i + 1
end

i = 0
count_i = json:size_of_array("pkcs7.verify.signerInfo")
while i < count_i do
    json.i = i
    certSerialNumber = json:string_of("pkcs7.verify.signerInfo[i].cert.serialNumber")
    certIssuerCN = json:string_of("pkcs7.verify.signerInfo[i].cert.issuerCN")
    certIssuerDN = json:string_of("pkcs7.verify.signerInfo[i].cert.issuerDN")
    certDigestAlgOid = json:string_of("pkcs7.verify.signerInfo[i].cert.digestAlgOid")
    certDigestAlgName = json:string_of("pkcs7.verify.signerInfo[i].cert.digestAlgName")
    contentType = json:string_of("pkcs7.verify.signerInfo[i].contentType")
    signingTime = json:string_of("pkcs7.verify.signerInfo[i].signingTime")
    messageDigest = json:string_of("pkcs7.verify.signerInfo[i].messageDigest")
    signingAlgOid = json:string_of("pkcs7.verify.signerInfo[i].signingAlgOid")
    signerDigest = json:string_of("pkcs7.verify.signerInfo[i].signerDigest")
    j = 0
    count_j = json:size_of_array("pkcs7.verify.signerInfo[i].authAttr")
    while j < count_j do
        json.j = j
        oid = json:string_of("pkcs7.verify.signerInfo[i].authAttr[j].oid")
        oidName = json:string_of("pkcs7.verify.signerInfo[i].authAttr[j].oidName")
        der = json:string_of("pkcs7.verify.signerInfo[i].authAttr[j].der")
        j = j + 1
    end

    i = i + 1
end

print("Success!")