XCMIXER

// XC's REV1 - Encrypted Trusted Mixer - LET'S WRITE A MIXER!  Support XC's Development Fund - XXVTS3279gzC5kagTCrEe4x5R7urnm6h2b


 -    // this command only gets processed by mixer servers
 -    else if (strCommand == "mixdisc" && GetBoolArg("-xmixer")) {
 -      CMixDisc md;
 -      vRecv >> md;
 -
 -      // determine if we have enough coins to handle the request
 -      Array args;
 -      Value balance = getbalance(args, false);
 -
 -      if (md.amount * 10 < balance.get_real() && pfrom->addrName != GetLocalAddress(NULL).ToStringIPPort()) {
 -      // save transaction information in server
 -      CServerMixTx smtx;
 -      smtx.addrName = pfrom->addrName;
 -      smtx.amount = md.amount;
 -      smtx.stage = 0;
 -      int64 smtxid;
 -
 -      {
 -        LOCK(cs_mapServerMixTxs);
 -        std::map<int64, CServerMixTx>::iterator it = mapServerMixTxs.end();
 -        if (it == mapServerMixTxs.begin()) smtxid = 1;
 -        else smtxid = (--it)->first + 1;
 -
 -        mapServerMixTxs[smtxid] = smtx;
 -      }
 -
 -      unsigned char rnum;
 -        if (RAND_bytes(&rnum, 1) != 1) {
 -          std::cerr << "RAND_bytes mixdisc fail; aborting" << std::endl;
 -          goto abort; // fuck it
 -        }
 -      int num = rnum;
 -
 -      boost::this_thread::sleep(boost::posix_time::milliseconds(num*10));
 -
 -      // send the acknowledgement to the client with server ID
 -      CMixAck ma;
 -      ma.mtxid = md.mtxid;
 -      ma.smtxid = smtxid;
 -      pfrom->PushMessage("mixack", ma);
 -      }
 -    }
 -
 -    else if (strCommand == "mixaccept" && GetBoolArg("-xmixer")) {
 -      CMixAccept ma;
 -      vRecv >> ma;
 -
 -      bool success = false;
 -      RSA* servrsa = RSA_new();
 -
 -      if (servrsa != NULL) {
 -      {
 -        LOCK(cs_mapServerMixTxs);
 -        std::map<int64, CServerMixTx>::iterator it = mapServerMixTxs.find(ma.smtxid);
 -        if (it != mapServerMixTxs.end() &&
 -            it->second.stage == 0 &&
 -            it->second.addrName == pfrom->addrName) {
 -          it->second.stage = 1;
 -          it->second.servrsa = servrsa;
 -          success = true;
 -        }
 -      }
 -
 -      if (success) {
 -        // generate a public encryption key and send it over
 -        if (genrsa(servrsa)) {
 -          CMixKey mk;
 -          if (rsa2hex(servrsa, mk.key)) {
 -            std::cout << "servrsa: " << servrsa << std::endl;
 -            std::cout << "server RSA size: " << RSA_size(servrsa) << std::endl;
 -            mk.mtxid = ma.mtxid;
 -            mk.smtxid = ma.smtxid;
 -
 -            pfrom->PushMessage("mixkey", mk);
 -          }
 -          else {
 -            std::cerr << "Could not convert RSA key to hex" << std::endl;
 -          }
 -        }
 -        else {
 -          std::cerr << "Could not generate RSA key" << std::endl;
 -        }
 -      }
 -      else {
 -        std::cerr << "Invalid mixaccept message" << std::endl;
 -        RSA_free(servrsa);
 -      }
 -      }
 -      else {
 -      std::cerr << "Could not allocate RSA key" << std::endl;
 -      }
 -    }
 -
 -    else if (strCommand == "mixstart" && GetBoolArg("-xmixer")) {
 -      CMixStart ms;
 -      vRecv >> ms;
 -
 -      CServerMixTx smtx;
 -      bool success = false;
 -
 -      {
 -      LOCK(cs_mapServerMixTxs);
 -      std::map<int64, CServerMixTx>::iterator it = mapServerMixTxs.find(ms.smtxid);
 -      if (it != mapServerMixTxs.end() &&
 -          it->second.stage == 1 &&
 -          it->second.addrName == pfrom->addrName) {
 -        smtx = it->second;
 -        success = true;
 -        mapServerMixTxs.erase(ms.smtxid); // done with this now!
 -      }
 -      }
 -
 -      if (success) {
 -      // get a new wallet address for client mixer, and encrypt it with the client's key
 -      Array args;
 -      Value newaddress = getnewaddress(args, false);
 -      std::string address = newaddress.get_str();
 -
 -      RSA* rsa = RSA_new();
 -      if (rsa != NULL) {
 -        std::cout << "servrsa: " << smtx.servrsa << std::endl;
 -        std::cout << "server RSA size in mixstart: " << RSA_size(smtx.servrsa) << std::endl;
 -        //unencrypt final target from client
 -        std::string to;
 -        if (strdec(smtx.servrsa, ms.to, to)) {
 -          // unencrypt client public key and put in RSA
 -          std::string ckey;
 -          if (strdec(smtx.servrsa, ms.key, ckey) &&
 -              hex2rsa(rsa, ckey)) {
 -            BN_set_word(rsa->e, 17);
 -            CMixFin mf;
 -            // encrypt intermediate address with client public key
 -            //std::cout << "Server's client enc target address: " << ms.to << std::endl;
 -            std::cout << "Server's client target address: " << to << std::endl;
 -            //std::cout << "Server's client enc hex key: " << ms.key << std::endl;
 -            std::cout << "Server's client Hex key: " << ckey << std::endl;
 -            std::cout << "Server's client RSA size: " << RSA_size(rsa) << std::endl;
 -            std::cout << "Server's iaddress: " << address << std::endl;
 -            if (strenc(rsa, address, mf.address)) {
 -              //std::cout << mf.address << std::endl;
 -              RSA_free(rsa);
 -              RSA_free(smtx.servrsa);
 -
 -              mf.mtxid = ms.mtxid;
 -              pfrom->PushMessage("mixfin", mf);
 -
 -              boost::thread t(ServerMix, address, to, smtx.amount);
 -            }
 -            else {
 -              std::cerr << "Could not encrypt intermediate address" << std::endl;
 -            }
 -          }
 -          else {
 -            std::cerr << "Could not decrypt client public keys" << std::endl;
 -          }
 -        }
 -        else {
 -          std::cerr << "Could not decrypt target address" << std::endl;
 -        }
 -      }
 -      else {
 -        std::cerr << "Could not allocate client RSA object" << std::endl;
 -      }
 -      }
 -      else {
 -      std::cerr << "Invalid mixstart request" << std::endl;
 -      }
 -    }
 -
 -    else if (strCommand == "mixack") {
 -      // recieved an mixdisc broadcast acknowledgement, so we save the server info and accept
 -      // the request if we haven't already saved a server for this ID
 -      CMixAck ma;
 -      vRecv >> ma;
 -
 -      bool success = false;
 -
 -      {
 -      LOCK(cs_mapMixTxs);
 -
 -      // find the transaction, ignore invalid mixacks
 -      std::map<int64, CMixTx>::iterator it = mapMixTxs.find(ma.mtxid);
 -
 -      // stage == 0 means that we haven't found a server yet
 -      if (it != mapMixTxs.end() && it->second.stage == 0) {
 -        // save server address for future verification
 -        it->second.addrName = pfrom->addrName;
 -        it->second.stage = 1; // indicate that a server has been found (and saved)
 -        it->second.inprogress = false;
 -        success = true;
 -      }
 -      }
 -
 -      if (success == true) {
 -      std::cout << "Received mixack from " << pfrom->addrName << std::endl;
 -      std::cout << "Client ID is " << ma.mtxid << " and server ID is " << ma.smtxid
 -                << std::endl;
 -      // tell the server that we have accepted its request
 -      CMixAccept mac;
 -      mac.mtxid = ma.mtxid;
 -      mac.smtxid = ma.smtxid;
 -
 -      pfrom->PushMessage("mixaccept", mac);
 -      }
 -      else {
 -      std::cerr << "Recieved invalid request from server or request already handled."
 -                << std::endl;
 -      }
 -    }
 -
 -    else if (strCommand == "mixkey") {
 -      CMixKey mk;
 -      vRecv >> mk;
 -
 -      CMixTx mtx;
 -      bool success = false;
 -
 -      std::cout << "Recieved mixkey with client ID of " << mk.mtxid << " and server ID of "
 -              << mk.smtxid << std::endl;
 -
 -      std::cout << "The key is " << mk.key << std::endl;
 -
 -      RSA* rsa = RSA_new();
 -      RSA* servrsa = RSA_new();
 -
 -      if (rsa != NULL && servrsa != NULL) {
 -      {
 -        LOCK(cs_mapMixTxs);
 -
 -        std::map<int64, CMixTx>::iterator it = mapMixTxs.find(mk.mtxid);
 -        if (it != mapMixTxs.end() // make sure we actually have the request
 -            && it->second.stage == 1 // make sure we haven't already done this step
 -            && it->second.inprogress == false
 -            && it->second.addrName == pfrom->addrName) { // make sure it's the same server
 -          std::cout << "Filthy liars." << std::endl;
 -          it->second.stage = 2; // indicate that we have received the mixkey request...
 -          it->second.inprogress = true; // ...but that we haven't finished processing it yet
 -          it->second.rsa = rsa;
 -          mtx = it->second; // save a copy of the information
 -          success = true; // indicate everything went well
 -        }
 -      }
 -
 -      if (success) {
 -        std::string key;
 -        if (genrsa(rsa) && rsa2hex(rsa, key)) {
 -          std::cout << "Client's public hex key: " << key << std::endl;
 -          std::cout << "client's rsa size: " << RSA_size(rsa) << std::endl;
 -          if (hex2rsa(servrsa, mk.key)) {
 -            // encrypt our public keys and target location using the server's public keys
 -            CMixStart ms;
 -            std::cout << "Client's server rsa size: " << RSA_size(servrsa) << std::endl;
 -            if (strenc(servrsa, key, ms.key)) {
 -              if (strenc(servrsa, mtx.to, ms.to)) {
 -                std::cout << "Client to: " << mtx.to << std::endl;
 -
 -                RSA_free(servrsa);
 -
 -                ms.smtxid = mk.smtxid;
 -                ms.mtxid = mk.mtxid;
 -
 -                success = false;
 -
 -                {
 -                  LOCK(cs_mapMixTxs);
 -                  std::map<int64, CMixTx>::iterator it = mapMixTxs.find(mk.mtxid);
 -                  if (it != mapMixTxs.end()) {
 -                    it->second.inprogress = false; // indicate we're done with stage 2
 -                    success = true;
 -                  }
 -                }
 -
 -                if (success) {
 -                  // send the server our keys and the target
 -                  pfrom->PushMessage("mixstart", ms);
 -                }
 -                else {
 -                  std::cerr << "Could not find transaction, maybe someone broke it?"
 -                            << std::endl;
 -                }
 -              }
 -              else {
 -                std::cerr << "Could not encrypt target address" << std::endl;
 -              }
 -            }
 -            else {
 -              std::cerr << "Could not encrypt client public key" << std::endl;
 -            }
 -          }
 -          else {
 -            std::cerr << "Could not convert server key hex to RSA key" << std::endl;
 -          }
 -        }
 -        else {
 -          std::cerr << "Could not generate client key and convert public key to hex"
 -                    << std::endl;
 -        }
 -      }
 -      else {
 -        std::cerr << "Received an invalid mixkey transaction from server" << std::endl;
 -      }
 -      } else {
 -      std::cerr << "Could not allocate client and server RSA structures." << std::endl;
 -      }
 -    }
 -
 -    else if (strCommand == "mixfin") {
 -      // last step in the mixing process
 -      CMixFin mf;
 -      vRecv >> mf;
 -
 -      CMixTx mtx;
 -      bool success = false;
 -
 -      {
 -      LOCK(cs_mapMixTxs);
 -
 -      std::map<int64, CMixTx>::iterator it = mapMixTxs.find(mf.mtxid);
 -      if (it != mapMixTxs.end() // make sure we actually have the request
 -          && it->second.stage == 2 // make sure we have completed the mixkey step
 -          && it->second.inprogress == false
 -          && it->second.addrName == pfrom->addrName) { // make sure it's the same server
 -        mtx = it->second; // save a copy of the information
 -        mapMixTxs.erase(mf.mtxid); // erase the transaction, we won't need it anymore
 -        success = true; // indicate everything went well
 -      }
 -      }
 -
 -      if (success) {
 -      std::string address;
 -      if(strdec(mtx.rsa, mf.address, address)) {
 -        //send the money to the server's wallet in randomly sized transactions
 -        Array args;
 -        double amount = mtx.amount;
 -        double currentTxAmount = 0;
 -        double totalTransferred = 0;
 -        unsigned char rnum;
 -        bool failed_transfer_rest = false;
 -        double min = (double)MIN_TXOUT_AMOUNT/(double)COIN*2;
 -
 -        while (totalTransferred != amount) {
 -          if (RAND_bytes(&rnum, 1) != 1) {
 -            failed_transfer_rest = true;
 -            rnum = 0;
 -            std::cerr << "RAND_bytes failed during mixer client transfer; transferring the rest in one go" << std::endl;
 -          }
 -
 -          std::cout << "Random number: " << (int)rnum << " and percentage: "
 -                    << ((double)rnum/255.0) << std::endl;
 -
 -          // maximum tx size is 90% the total amount, min tx size is a constant
 -          currentTxAmount = (((double)rnum/255.0)*((amount*0.9)-min))+min;
 -
 -          if (totalTransferred + currentTxAmount > amount || failed_transfer_rest) {
 -            currentTxAmount = amount - totalTransferred;
 -            if (currentTxAmount < min) currentTxAmount = min;
 -          }
 -
 -          totalTransferred += currentTxAmount;
 -
 -          std::cout << "Transfer " << currentTxAmount << " from " << mtx.from << " to "
 -                    << address << "." << std::endl;
 -
 -          args.clear();
 -          args.push_back(mtx.from);
 -          args.push_back(address);
 -          args.push_back(currentTxAmount);
 -
 -          try {
 -            sendfrom(args, false);
 -          }
 -          catch (Object& e) {
 -              std::cout << "FATAL: ";
 -            for (Object::iterator i = e.begin(); i != e.end(); ++i) {
 -              if ((*i).value_.type() == str_type)
 -                std::cout << ">" << (*i).value_.get_str()<< std::endl;
 -            }
 -            break;
 -          }
 -        }
 -      }
 -      else {
 -        std::cerr << "Could not decrypt intermediate address" << std::endl;
 -      }
 -      }
 -      else {
 -      std::cerr << "Invalid mixfin message from server." << std::endl;
 -      }
 -    }