How to extract subscriber information from an Authenticode digitally signed PE file encoded using ASN1?

Question

I need to extract SignerInfo from an Authenticode digitally signed PE file in an ASN1 structure.

INFO : The PE file contains the authenticator with the offset specified by the Security Directory RVA inside Optional Header Data Directories . I tried to start reading a document available in the Microsoft Authenticode PE Signature Format , but I had no luck as I am very new to SSL / TSL.

My question is:

• Is there a way to parse binary files and print the data structure in C String Format?

• Is there a way I can SignerInfo these binaries and point to SignerInfo or SignerName ?

NOTE : I do not want to use any platform dependent APIs, as I want the code not to be platform dependent.

Thanks in "Promotion to all gurus" :-)

UPDATE: I found the code in C #. Can someone help me find the C equivalent of the same.

 using System; using System.IO; using System.Text; using System.Security.Cryptography.X509Certificates; public class CertInfo { public static void Main(String[] args) { byte[] certBytes; X509Certificate x509cert; while (true) { Console.WriteLine("\nEnter File Name: "); String filename = Console.ReadLine(); if (filename == "") //exit while(true) loop break; if (!File.Exists(filename)) { Console.WriteLine("File \"{0}\" does not exist!\n", filename); continue; } try { //try binary DER format first x509cert = X509Certificate.CreateFromCertFile(filename); showCertInfo(x509cert); } catch (System.Security.Cryptography.CryptographicException cryptder) { //not binary DER StreamReader sr = File.OpenText(filename); String filestr = sr.ReadToEnd(); sr.Close(); StringBuilder sb = new StringBuilder(filestr); sb.Replace("-----BEGIN CERTIFICATE-----", ""); sb.Replace("-----END CERTIFICATE-----", ""); //Decode try { //see if the file is a valid Base64 encoded cert certBytes = Convert.FromBase64String(sb.ToString()); x509cert = new X509Certificate(certBytes); showCertInfo(x509cert); } catch (System.FormatException formexc) { Console.WriteLine("Not valid binary DER or Base64 X509 certificate format"); } catch (System.Security.Cryptography.CryptographicException cryptb64) { Console.WriteLine("Not valid binary DER or Base64 X509 certificate format"); } } } // end while true } private static void showCertInfo(X509Certificate x509cert) { Console.WriteLine("Name: " + x509cert.GetName()); Console.WriteLine("Issuer: " + x509cert.GetIssuerName()); Console.WriteLine("Serial Number: " + x509cert.GetSerialNumberString()); Console.WriteLine("Expiration Date: " + x509cert.GetExpirationDateString()); Console.WriteLine("PublicKey: " + x509cert.GetPublicKeyString()); } }