Verify MRTD AA signature.cpp

//  g++ -Wall ecdsa-test.cpp -o ecdsa-test -lcryptopp && ./ecdsa-test

#include <iostream>
using std::cout;
using std::cerr;
using std::endl;

#include <string>
using std::string;

#include "cryptopp/eccrypto.h"
using CryptoPP::ECP;
using CryptoPP::ECDSA;

#include "cryptopp/sha.h"
using CryptoPP::SHA256;

#include "cryptopp/queue.h"
using CryptoPP::ByteQueue;

#include "cryptopp/oids.h"
using CryptoPP::OID;

// ASN1 is a namespace, not an object
#include "cryptopp/asn.h"
using namespace CryptoPP::ASN1;

#include "cryptopp/files.h"
using CryptoPP::FileSource;
using CryptoPP::FileSink;

#include "cryptopp/integer.h"
using CryptoPP::Integer;

#include "cryptopp/cryptlib.h"
using CryptoPP::PublicKey;
using CryptoPP::BufferedTransformation;

void LoadPublicKey(const string& filename, PublicKey& key);
void Load(const string& filename, BufferedTransformation& bt);

void LoadPublicKey(const string& filename, PublicKey& key)
{
  ByteQueue queue;

  Load(filename, queue);
  key.Load(queue);
}

void Load(const string& filename, BufferedTransformation& bt)
{
  FileSource file(filename.c_str(), true /*pumpAll*/);

  file.TransferTo(bt);
  bt.MessageEnd();
}

void LoadFile(const string& filename, std::vector<char>& buffer)
{
  std::ifstream file(filename.c_str(), std::ios::binary | std::ios::ate);
  std::streamsize size = file.tellg();
  file.seekg(0, std::ios::beg);
  file.read(buffer.data(), size);
}

int main()
{
  ECDSA<ECP, SHA256>::PublicKey pubKey;
  LoadPublicKey("public", pubKey);
  ECDSA<ECP, SHA256>::Verifier verifier( pubKey );

  std::vector<char> signature(80);
  std::vector<char> data(8);
  LoadFile("signature", signature);
  LoadFile("data", data);

  bool result = verifier.VerifyMessage( (const byte*)data.data(), data.size(), (const byte*)signature.data(), signature.size() );

  if(result)
      cout << "Verified signature on message" << endl;
  else
      cerr << "Failed to verify signature on message" << endl;

  return 0;
}