Added registration.

Currently doesn't return any valid result, hence host believes device
failed to register, however, insecure storage of keys does occur.

Storage.cpp

@@ -0,0 +1,90 @@
+#include "Storage.hpp"
+#include <exception>
+#include <sstream>
+#include "Base64.tpp"
+#include <iostream>
+
+using namespace std;
+
+std::string Storage::filename{};
+std::map<Storage::KeyHandle, Storage::AppParam> Storage::appParams{};
+std::map<Storage::KeyHandle, Storage::PrivKey>  Storage::privKeys{};
+std::map<Storage::KeyHandle, Storage::PubKey>   Storage::pubKeys{};
+
+void Storage::init(const string &dirPrefix)
+{
+	Storage::filename = dirPrefix + "U2F_Priv_Keys.txt";
+	ifstream file{ Storage::filename };
+	string line;
+	size_t lineNumber = 0;
+
+	base64::decoder decoder{};
+	
+	while (getline(file, line))
+	{
+		auto strLineNum = to_string(lineNumber);
+		stringstream ss{ line };
+		string keyHStr,   appStr,   privStr,   pubStr;
+		ss >>  keyHStr >> appStr >> privStr >> pubStr;
+
+		if (!ss)
+			throw runtime_error{ string{ "Invalid syntax of line " } + strLineNum };
+
+		char *endP = nullptr;
+		Storage::KeyHandle keyH{ strtoull(keyHStr.c_str(), &endP, 10) };
+
+		if (!endP)
+			throw runtime_error{ "Invalid keyhandle format on line " + strLineNum };
+
+		//if (appStr.size() != 32)
+		//	throw runtime_error{ "Invalid length of app parameter on line " + strLineNum };
+		//if (privStr.size() != 32)
+		//	throw runtime_error{ "Invalid length of private key on line " + strLineNum };
+		//if (pubStr.size()  != 65)
+		//	throw runtime_error{ "Invalid length of public key on line " + strLineNum };
+
+		Storage::AppParam appParam{};
+		b64decode(appStr, appParam);
+
+		Storage::PrivKey  privKey{};
+		b64decode(privStr, privKey);
+
+		Storage::PubKey   pubKey{};
+		b64decode(pubStr, pubKey);
+
+		Storage::appParams[keyH] = appParam;
+		Storage::privKeys[keyH]  = privKey;
+		Storage::pubKeys[keyH]   = pubKey;
+
+		lineNumber++;
+	}
+}
+
+void Storage::save()
+{
+	ofstream file{ Storage::filename };
+	base64::encoder encoder{};
+
+	for (auto &keypair : Storage::appParams)
+	{
+		const auto keyID = keypair.first;
+		const auto appParam = keypair.second;
+		const auto privKey = Storage::privKeys[keypair.first];
+		const auto pubKey = Storage::pubKeys[keypair.first];
+
+		file << keyID;
+		file << ' ';
+
+		string appPStr{};
+		b64encode(appParam, appPStr);
+		file << appPStr << ' ';
+
+		string privKStr{};
+		b64encode(privKey, privKStr);
+		file << privKStr << ' ';
+
+		string pubKStr{};
+		b64encode(pubKey, pubKStr);
+		file << pubKStr << endl;
+	}
+}