#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <cstdlib>
#include <memory>

#include <botan/botan.h>
#include <botan/libstate.h>
#include <botan/rsa.h>
#include <botan/dsa.h>
#include <botan/dh.h>

#include <botan/nr.h>
#include <botan/rw.h>
#include <botan/elgamal.h>
#include <botan/dlies.h>

#include <botan/filters.h>
#include <botan/look_pk.h>
#include <botan/numthry.h>

#include <botan/x931_rng.h>
#include <botan/libstate.h>
using namespace Botan;

#include "common.h"

static BigInt to_bigint(const std::string& h)
   {
   return BigInt::decode(reinterpret_cast<const byte*>(h.data()),
                         h.length(), BigInt::Hexadecimal);
   }

#define DEBUG 0

class Fixed_Output_RNG : public RandomNumberGenerator
   {
   public:
      byte random()
         {
         if(position < output.size())
            return output[position++];

         throw Botan::Invalid_State("Fixed_Output_RNG: out of bits");
         }
      void randomize(byte out[], u32bit len) throw()
         {
         for(u32bit j = 0; j != len; j++)
            out[j] = random();
         }
      std::string name() const { return "Fixed_Output_RNG"; }
      void clear() throw() {}
      void add_randomness(const byte[], u32bit) throw() {}
      Fixed_Output_RNG(const SecureVector<byte>& x)
         {
         output = x;
         position = 0;
         }
   private:
      SecureVector<byte> output;
      u32bit position;
   };

void do_pk_keygen_tests();
extern void do_x509_tests();

u32bit validate_dsa_sig(const std::string&, const std::vector<std::string>&);
u32bit validate_dsa_ver(const std::string&, const std::vector<std::string>&);

u32bit validate_rsa_enc(const std::string&, const std::vector<std::string>&);
u32bit validate_rsa_enc_pkcs8(const std::string&,
                              const std::vector<std::string>&);
u32bit validate_rsa_sig(const std::string&, const std::vector<std::string>&);
u32bit validate_rsa_ver(const std::string&, const std::vector<std::string>&);
u32bit validate_rsa_ver_x509(const std::string&,
                             const std::vector<std::string>&);
u32bit validate_rw_ver(const std::string&, const std::vector<std::string>&);
u32bit validate_rw_sig(const std::string&, const std::vector<std::string>&);
u32bit validate_nr_sig(const std::string&, const std::vector<std::string>&);
u32bit validate_elg_enc(const std::string&, const std::vector<std::string>&);
u32bit validate_dh(const std::string&, const std::vector<std::string>&);
u32bit validate_dlies(const std::string&, const std::vector<std::string>&);

u32bit do_pk_validation_tests(const std::string& filename)
   {
   std::ifstream test_data(filename.c_str());

   if(!test_data)
      throw Botan::Stream_IO_Error("Couldn't open test file " + filename);

   u32bit errors = 0, alg_count = 0;
   std::string algorithm, print_algorithm;

   while(!test_data.eof())
      {
      if(test_data.bad() || test_data.fail())
         throw Botan::Stream_IO_Error("File I/O error reading from " +
                                      filename);

      std::string line;
      std::getline(test_data, line);

      strip_comments(line);
      if(line.size() == 0) continue;

      // Do line continuation
      while(line[line.size()-1] == '\\' && !test_data.eof())
         {
         line.replace(line.size()-1, 1, "");
         std::string nextline;
         std::getline(test_data, nextline);
         strip_comments(nextline);
         if(nextline.size() == 0) continue;
         line.push_back('\n');
         line += nextline;
         }

      if(line[0] == '[' && line[line.size() - 1] == ']')
         {
         std::string old_algo = print_algorithm;
         algorithm = line.substr(1, line.size() - 2);
         print_algorithm = algorithm;
         if(print_algorithm.find("_PKCS8") != std::string::npos)
            print_algorithm.replace(print_algorithm.find("_PKCS8"), 6, "");
         if(print_algorithm.find("_X509") != std::string::npos)
            print_algorithm.replace(print_algorithm.find("_X509"), 5, "");
         if(print_algorithm.find("_VA") != std::string::npos)
            print_algorithm.replace(print_algorithm.find("_VA"), 3, "");

         if(old_algo != print_algorithm && old_algo != "")
            {
            std::cout << std::endl;
            alg_count = 0;
            }

         if(old_algo != print_algorithm)
            std::cout << "Testing " << print_algorithm << ": ";
         continue;
         }

      std::cout << '.';
      std::cout.flush();

      std::vector<std::string> substr = parse(line);

#if DEBUG
      std::cout << "Testing: " << print_algorithm << std::endl;
#endif

      u32bit new_errors = 0;

      if(algorithm.find("DSA/") != std::string::npos)
         new_errors = validate_dsa_sig(algorithm, substr);
      else if(algorithm.find("DSA_VA/") != std::string::npos)
         new_errors = validate_dsa_ver(algorithm, substr);

      else if(algorithm.find("RSAES_PKCS8/") != std::string::npos)
         new_errors = validate_rsa_enc_pkcs8(algorithm, substr);
      else if(algorithm.find("RSAVA_X509/") != std::string::npos)
         new_errors = validate_rsa_ver_x509(algorithm, substr);

      else if(algorithm.find("RSAES/") != std::string::npos)
         new_errors = validate_rsa_enc(algorithm, substr);
      else if(algorithm.find("RSASSA/") != std::string::npos)
         new_errors = validate_rsa_sig(algorithm, substr);
      else if(algorithm.find("RSAVA/") != std::string::npos)
         new_errors = validate_rsa_ver(algorithm, substr);
      else if(algorithm.find("RWVA/") != std::string::npos)
         new_errors = validate_rw_ver(algorithm, substr);
      else if(algorithm.find("RW/") != std::string::npos)
         new_errors = validate_rw_sig(algorithm, substr);
      else if(algorithm.find("NR/") != std::string::npos)
         new_errors = validate_nr_sig(algorithm, substr);
      else if(algorithm.find("ElGamal/") != std::string::npos)
         new_errors = validate_elg_enc(algorithm, substr);
      else if(algorithm.find("DH/") != std::string::npos)
         new_errors = validate_dh(algorithm, substr);
      else if(algorithm.find("DLIES/") != std::string::npos)
         new_errors = validate_dlies(algorithm, substr);
      else
         std::cout << "WARNING: Unknown PK algorithm "
                   << algorithm << std::endl;

      alg_count++;
      errors += new_errors;

      if(new_errors)
         std::cout << "ERROR: \"" << algorithm << "\" failed test #"
                   << std::dec << alg_count << std::endl;
      }

   std::cout << std::endl;

   global_state().set_prng(new ANSI_X931_RNG);
   for(u32bit j = 0; j != 2; j++)
      global_state().seed_prng(true, 384);

   do_pk_keygen_tests();
   do_x509_tests();

   return errors;
   }

void dump_data(const SecureVector<byte>& out,
               const SecureVector<byte>& expected)
   {
   Pipe pipe(new Hex_Encoder);

   pipe.process_msg(out);
   pipe.process_msg(expected);
   std::cout << "Got: " << pipe.read_all_as_string(0) << std::endl;
   std::cout << "Exp: " << pipe.read_all_as_string(1) << std::endl;
   }

void validate_decryption(PK_Decryptor* d, const std::string& algo,
                         const SecureVector<byte> ctext,
                         const SecureVector<byte> ptext,
                         bool& failure)
   {
   SecureVector<byte> decrypted = d->decrypt(ctext);
   if(decrypted != ptext)
      {
      std::cout << "FAILED (decrypt): " << algo << std::endl;
      dump_data(decrypted, ptext);
      failure = true;
      }
   delete d;
   }

void validate_encryption(PK_Encryptor* e, PK_Decryptor* d,
                         const std::string& algo, const std::string& input,
                         const std::string& random, const std::string& exp,
                         bool& failure)
   {
   SecureVector<byte> message = decode_hex(input);

   global_state().set_prng(new Fixed_Output_RNG(decode_hex(random)));

   SecureVector<byte> expected = decode_hex(exp);

   SecureVector<byte> out = e->encrypt(message);
   if(out != expected)
      {
      std::cout << "FAILED (encrypt): " << algo << std::endl;
      dump_data(out, expected);
      failure = true;
      }

   global_state().set_prng(new ANSI_X931_RNG);
   for(u32bit j = 0; j != 2; j++)
      global_state().seed_prng(true, 384);

   validate_decryption(d, algo, out, message, failure);
   delete e;
   }

void validate_signature(PK_Verifier* v, PK_Signer* s, const std::string& algo,
                        const std::string& input, const std::string& random,
                        const std::string& exp, bool& failure)
   {
   SecureVector<byte> message = decode_hex(input);
   global_state().set_prng(new Fixed_Output_RNG(decode_hex(random)));

   SecureVector<byte> expected = decode_hex(exp);

   SecureVector<byte> sig = s->sign_message(message, message.size());

   if(sig != expected)
      {
      std::cout << "FAILED (sign): " << algo << std::endl;
      dump_data(sig, expected);
      failure = true;
      }

   if(!v->verify_message(message, message.size(), sig, sig.size()))
      {
      std::cout << "FAILED (verify): " << algo << std::endl;
      failure = true;
      }

   /* This isn't a very thorough testing method, but it will hopefully
      catch any really horrible errors */
   sig[0]++;
   if(v->verify_message(message, message.size(), sig, sig.size()))
      {
      std::cout << "FAILED (accepted bad sig): " << algo << std::endl;
      failure = true;
      }

   global_state().set_prng(new ANSI_X931_RNG);
   for(u32bit j = 0; j != 2; j++)
      global_state().seed_prng(true, 384);

   delete v;
   delete s;
   }

void validate_kas(PK_Key_Agreement* kas, const std::string& algo,
                  const SecureVector<byte>& pubkey, const std::string& output,
                  u32bit keylen, bool& failure)
   {
   SecureVector<byte> expected = decode_hex(output);

   SecureVector<byte> got = kas->derive_key(keylen,
                                            pubkey, pubkey.size()).bits_of();

   if(got != expected)
      {
      std::cout << "FAILED: " << algo << std::endl;
      dump_data(got, expected);
      failure = true;
      }

   delete kas;
   }

u32bit validate_rsa_enc_pkcs8(const std::string& algo,
                              const std::vector<std::string>& str)
   {
   if(str.size() != 4 && str.size() != 5)
      throw Exception("Invalid input from pk_valid.dat");

   std::string pass;
   if(str.size() == 5) pass = str[4];
   strip_newlines(pass); /* it will have a newline thanks to the messy
                                decoding method we use */

   DataSource_Memory keysource(reinterpret_cast<const byte*>(str[0].c_str()),
                               str[0].length());

   Private_Key* privkey = PKCS8::load_key(keysource, pass);

   RSA_PrivateKey* rsapriv = dynamic_cast<RSA_PrivateKey*>(privkey);
   if(!rsapriv)
      throw Invalid_Argument("Bad key load for RSA key");

   RSA_PublicKey* rsapub = dynamic_cast<RSA_PublicKey*>(rsapriv);

   std::string eme = algo.substr(12, std::string::npos);

   PK_Encryptor* e = get_pk_encryptor(*rsapub, eme);
   PK_Decryptor* d = get_pk_decryptor(*rsapriv, eme);

   bool failure = false;
   validate_encryption(e, d, algo, str[1], str[2], str[3], failure);
   delete privkey;
   return (failure ? 1 : 0);
   }

u32bit validate_rsa_enc(const std::string& algo,
                        const std::vector<std::string>& str)
   {
   if(str.size() != 6)
      throw Exception("Invalid input from pk_valid.dat");

   RSA_PrivateKey privkey(to_bigint(str[1]), to_bigint(str[2]),
                          to_bigint(str[0]));
   RSA_PublicKey pubkey = privkey;

   std::string eme = algo.substr(6, std::string::npos);

   PK_Encryptor* e = get_pk_encryptor(pubkey, eme);
   PK_Decryptor* d = get_pk_decryptor(privkey, eme);

   bool failure = false;
   validate_encryption(e, d, algo, str[3], str[4], str[5], failure);
   return (failure ? 1 : 0);
   }

u32bit validate_elg_enc(const std::string& algo,
                        const std::vector<std::string>& str)
   {
   if(str.size() != 6 && str.size() != 7)
      throw Exception("Invalid input from pk_valid.dat");

   DL_Group domain(to_bigint(str[0]), to_bigint(str[1]));
   ElGamal_PrivateKey privkey(domain, to_bigint(str[2]), to_bigint(str[3]));
   ElGamal_PublicKey pubkey = privkey;

   std::string eme = algo.substr(8, std::string::npos);

   PK_Decryptor* d = get_pk_decryptor(privkey, eme);
   bool failure = false;

   if(str.size() == 7)
      {
      PK_Encryptor* e = get_pk_encryptor(pubkey, eme);
      validate_encryption(e, d, algo, str[4], str[5], str[6], failure);
      }
   else
      validate_decryption(d, algo, decode_hex(str[5]),
                          decode_hex(str[4]), failure);

   return (failure ? 1 : 0);
   }

u32bit validate_rsa_sig(const std::string& algo,
                        const std::vector<std::string>& str)
   {
   if(str.size() != 6)
      throw Exception("Invalid input from pk_valid.dat");

   RSA_PrivateKey privkey(to_bigint(str[1]), to_bigint(str[2]),
                          to_bigint(str[0]));
   RSA_PublicKey pubkey = privkey;

   std::string emsa = algo.substr(7, std::string::npos);

   PK_Verifier* v = get_pk_verifier(pubkey, emsa);
   PK_Signer* s = get_pk_signer(privkey, emsa);

   bool failure = false;
   validate_signature(v, s, algo, str[3], str[4], str[5], failure);
   return (failure ? 1 : 0);
   }

u32bit validate_rsa_ver(const std::string& algo,
                        const std::vector<std::string>& str)
   {
   if(str.size() != 5) /* is actually 4, parse() adds an extra empty one */
      throw Exception("Invalid input from pk_valid.dat");

   RSA_PublicKey key(to_bigint(str[1]), to_bigint(str[0]));

   std::string emsa = algo.substr(6, std::string::npos);

   PK_Verifier* v = get_pk_verifier(key, emsa);

   SecureVector<byte> msg = decode_hex(str[2]);
   SecureVector<byte> sig = decode_hex(str[3]);

   bool passed = v->verify_message(msg, msg.size(), sig, sig.size());

   delete v;

   return (passed ? 0 : 1);
   }

u32bit validate_rsa_ver_x509(const std::string& algo,
                             const std::vector<std::string>& str)
   {
   if(str.size() != 5) /* is actually 3, parse() adds extra empty ones */
      throw Exception("Invalid input from pk_valid.dat");

   DataSource_Memory keysource(reinterpret_cast<const byte*>(str[0].c_str()),
                               str[0].length());

   Public_Key* key = X509::load_key(keysource);

   RSA_PublicKey* rsakey = dynamic_cast<RSA_PublicKey*>(key);

   if(!rsakey)
      throw Invalid_Argument("Bad key load for RSA public key");

   std::string emsa = algo.substr(11, std::string::npos);

   PK_Verifier* v = get_pk_verifier(*rsakey, emsa);

   SecureVector<byte> msg = decode_hex(str[1]);
   SecureVector<byte> sig = decode_hex(str[2]);

   bool passed = v->verify_message(msg, msg.size(), sig, sig.size());

   delete v;
   delete key;

   return (passed ? 0 : 1);
   }

u32bit validate_rw_ver(const std::string& algo,
                       const std::vector<std::string>& str)
   {
   if(str.size() != 5)
      throw Exception("Invalid input from pk_valid.dat");

   RW_PublicKey key(to_bigint(str[1]), to_bigint(str[0]));

   std::string emsa = algo.substr(5, std::string::npos);

   PK_Verifier* v = get_pk_verifier(key, emsa);

   SecureVector<byte> msg = decode_hex(str[2]);
   SecureVector<byte> sig = decode_hex(str[3]);

   bool passed = v->verify_message(msg, msg.size(), sig, sig.size());

   delete v;

   return (passed ? 0 : 1);
   }

u32bit validate_rw_sig(const std::string& algo,
                       const std::vector<std::string>& str)
   {
   if(str.size() != 6)
      throw Exception("Invalid input from pk_valid.dat");

   RW_PrivateKey privkey(to_bigint(str[1]), to_bigint(str[2]),
                         to_bigint(str[0]));
   RW_PublicKey pubkey = privkey;

   std::string emsa = algo.substr(3, std::string::npos);

   PK_Verifier* v = get_pk_verifier(pubkey, emsa);
   PK_Signer* s = get_pk_signer(privkey, emsa);

   bool failure = false;
   validate_signature(v, s, algo, str[3], str[4], str[5], failure);
   return (failure ? 1 : 0);
   }

u32bit validate_dsa_sig(const std::string& algo,
                        const std::vector<std::string>& str)
   {
   if(str.size() != 4 && str.size() != 5)
      throw Exception("Invalid input from pk_valid.dat");

   std::string pass;
   if(str.size() == 5) pass = str[4];
   strip_newlines(pass); /* it will have a newline thanks to the messy
                                decoding method we use */

   DataSource_Memory keysource(reinterpret_cast<const byte*>(str[0].c_str()),
                               str[0].length());

   Private_Key* privkey = PKCS8::load_key(keysource, pass);

   DSA_PrivateKey* dsapriv = dynamic_cast<DSA_PrivateKey*>(privkey);
   if(!dsapriv)
      throw Invalid_Argument("Bad key load for DSA private key");

   DSA_PublicKey* dsapub = dynamic_cast<DSA_PublicKey*>(dsapriv);

   std::string emsa = algo.substr(4, std::string::npos);

   PK_Verifier* v = get_pk_verifier(*dsapub, emsa);
   PK_Signer* s = get_pk_signer(*dsapriv, emsa);

   bool failure = false;
   validate_signature(v, s, algo, str[1], str[2], str[3], failure);
   delete privkey;

   return (failure ? 1 : 0);
   }

u32bit validate_dsa_ver(const std::string& algo,
                        const std::vector<std::string>& str)
   {
   if(str.size() != 5) /* is actually 3, parse() adds extra empty ones */
      throw Exception("Invalid input from pk_valid.dat");

   DataSource_Memory keysource(reinterpret_cast<const byte*>(str[0].c_str()),
                               str[0].length());

   Public_Key* key = X509::load_key(keysource);

   DSA_PublicKey* dsakey = dynamic_cast<DSA_PublicKey*>(key);

   if(!dsakey)
      throw Invalid_Argument("Bad key load for DSA public key");

   std::string emsa = algo.substr(7, std::string::npos);

   PK_Verifier* v = get_pk_verifier(*dsakey, emsa);

   SecureVector<byte> msg = decode_hex(str[1]);
   SecureVector<byte> sig = decode_hex(str[2]);

   v->set_input_format(DER_SEQUENCE);
   bool passed = v->verify_message(msg, msg.size(), sig, sig.size());
   delete v;
   delete key;

   return (passed ? 0 : 1);
   }

u32bit validate_nr_sig(const std::string& algo,
                       const std::vector<std::string>& str)
   {
   if(str.size() != 8)
      throw Exception("Invalid input from pk_valid.dat");

   DL_Group domain(to_bigint(str[0]), to_bigint(str[1]), to_bigint(str[2]));
   NR_PrivateKey privkey(domain, to_bigint(str[4]), to_bigint(str[3]));
   NR_PublicKey pubkey = privkey;

   std::string emsa = algo.substr(3, std::string::npos);

   PK_Verifier* v = get_pk_verifier(pubkey, emsa);
   PK_Signer* s = get_pk_signer(privkey, emsa);

   bool failure = false;
   validate_signature(v, s, algo, str[5], str[6], str[7], failure);
   return (failure ? 1 : 0);
   }

u32bit validate_dh(const std::string& algo,
                   const std::vector<std::string>& str)
   {
   if(str.size() != 5 && str.size() != 6)
      throw Exception("Invalid input from pk_valid.dat");

   DL_Group domain(to_bigint(str[0]), to_bigint(str[1]));

   DH_PrivateKey mykey(domain, to_bigint(str[2]), 0);
   DH_PublicKey otherkey(domain, to_bigint(str[3]));

   std::string kdf = algo.substr(3, std::string::npos);

   u32bit keylen = 0;
   if(str.size() == 6)
      keylen = to_u32bit(str[5]);

   PK_Key_Agreement* kas = get_pk_kas(mykey, kdf);

   bool failure = false;
   validate_kas(kas, algo, otherkey.public_value(),
                str[4], keylen, failure);
   return (failure ? 1 : 0);
   }

u32bit validate_dlies(const std::string& algo,
                      const std::vector<std::string>& str)
   {
   if(str.size() != 6)
      throw Exception("Invalid input from pk_valid.dat");

   DL_Group domain(to_bigint(str[0]), to_bigint(str[1]));

   DH_PrivateKey from(domain, to_bigint(str[2]), 0);
   DH_PrivateKey to(domain, to_bigint(str[3]), 0);

   const std::string opt_str = algo.substr(6, std::string::npos);

   std::vector<std::string> options = split_on(opt_str, '/');

   if(options.size() != 3)
      throw Exception("DLIES needs three options: " + opt_str);

   std::string kdf = options[0];
   std::string mac = options[1];
   u32bit mac_key_len = to_u32bit(options[2]);

   PK_Decryptor* d = new DLIES_Decryptor(to, kdf, mac, mac_key_len);
   DLIES_Encryptor* e = new DLIES_Encryptor(from, kdf, mac, mac_key_len);
   e->set_other_key(to.public_value());

   std::string empty = "";
   bool failure = false;
   validate_encryption(e, d, algo, str[4], empty, str[5], failure);
   return (failure ? 1 : 0);
   }

void do_pk_keygen_tests()
   {
   std::cout << "Testing PK key generation: " << std::flush;

   /* Putting each key in a block reduces memory pressure, speeds it up */
#define IF_SIG_KEY(TYPE, BITS)     \
   {                               \
   TYPE key(BITS);                 \
   key.check_key(true);            \
   std::cout << '.' << std::flush; \
   }

#define DL_SIG_KEY(TYPE, GROUP)    \
   {                               \
   TYPE key(DL_Group(GROUP));  \
   key.check_key(true);            \
   std::cout << '.' << std::flush; \
   }

#define DL_ENC_KEY(TYPE, GROUP)    \
   {                               \
   TYPE key(DL_Group(GROUP));  \
   key.check_key(true);            \
   std::cout << '.' << std::flush; \
   }

#define DL_KEY(TYPE, GROUP)        \
   {                               \
   TYPE key(DL_Group(GROUP));  \
   key.check_key(true);            \
   std::cout << '.' << std::flush; \
   }

   IF_SIG_KEY(RSA_PrivateKey, 512);
   IF_SIG_KEY(RW_PrivateKey, 512);

   DL_SIG_KEY(DSA_PrivateKey, "dsa/jce/512");
   DL_SIG_KEY(DSA_PrivateKey, "dsa/jce/768");
   DL_SIG_KEY(DSA_PrivateKey, "dsa/jce/1024");

   DL_KEY(DH_PrivateKey, "modp/ietf/768");
   DL_KEY(DH_PrivateKey, "modp/ietf/2048");
   DL_KEY(DH_PrivateKey, "dsa/jce/1024");

   DL_SIG_KEY(NR_PrivateKey, "dsa/jce/512");
   DL_SIG_KEY(NR_PrivateKey, "dsa/jce/768");
   DL_SIG_KEY(NR_PrivateKey, "dsa/jce/1024");

   DL_ENC_KEY(ElGamal_PrivateKey, "modp/ietf/768");
   DL_ENC_KEY(ElGamal_PrivateKey, "modp/ietf/1024");
   DL_ENC_KEY(ElGamal_PrivateKey, "dsa/jce/1024");

   std::cout << std::endl;
   }