password hash cheching

database/CMakeLists.txt

@@ -1,9 +1,11 @@
 set(HEADERS
     dbinterface.h
+    exceptions.h
 )
 
 set(SOURCES
     dbinterface.cpp
+    exceptions.cpp
 )
 
 target_sources(${PROJECT_NAME} PRIVATE ${SOURCES})

database/dbinterface.h

@@ -26,6 +26,11 @@ public:
 
     const Type type;
 
+    class Duplicate;
+    class DuplicateLogin;
+    class EmptyResult;
+    class NoLogin;
+
 public:
     virtual void connect(const std::string& path) = 0;
     virtual void disconnect() = 0;
@@ -37,6 +42,7 @@ public:
     virtual void setVersion(uint8_t version) = 0;
 
     virtual unsigned int registerAccount(const std::string& login, const std::string& hash) = 0;
+    virtual std::string getAccountHash(const std::string& login) = 0;
 
 protected:
     DBInterface(Type type);

database/exceptions.cpp

@@ -0,0 +1,20 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "exceptions.h"
+
+DBInterface::Duplicate::Duplicate(const std::string& text):
+    std::runtime_error(text)
+{}
+
+DBInterface::DuplicateLogin::DuplicateLogin(const std::string& text):
+    Duplicate(text)
+{}
+
+DBInterface::EmptyResult::EmptyResult(const std::string& text):
+    std::runtime_error(text)
+{}
+
+DBInterface::NoLogin::NoLogin(const std::string& text):
+    EmptyResult(text)
+{}

database/exceptions.h

@@ -0,0 +1,26 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include "dbinterface.h"
+
+class DBInterface::Duplicate : public std::runtime_error {
+public:
+    explicit Duplicate(const std::string& text);
+};
+
+class DBInterface::DuplicateLogin : public DBInterface::Duplicate {
+public:
+    explicit DuplicateLogin(const std::string& text);
+};
+
+class DBInterface::EmptyResult : public std::runtime_error {
+public:
+    explicit EmptyResult(const std::string& text);
+};
+
+class DBInterface::NoLogin : public DBInterface::EmptyResult {
+public:
+    explicit NoLogin(const std::string& text);
+};

database/mysql/mysql.cpp

@@ -10,21 +10,17 @@
 
 #include "statement.h"
 #include "transaction.h"
+#include "database/exceptions.h"
 
 constexpr const char* versionQuery = "SELECT value FROM system WHERE `key` = 'version'";
 constexpr const char* updateQuery = "UPDATE system SET `value` = ? WHERE `key` = 'version'";
 constexpr const char* registerQuery = "INSERT INTO accounts (`login`, `type`, `password`) VALUES (?, 1, ?)";
 constexpr const char* lastIdQuery = "SELECT LAST_INSERT_ID() AS id";
 constexpr const char* assignRoleQuery = "INSERT INTO roleBindings (`account`, `role`) SELECT ?, roles.id FROM roles WHERE roles.name = ?";
+constexpr const char* selectHash = "SELECT password FROM accounts where login = ?";
 
 static const std::filesystem::path buildSQLPath = "database";
 
-struct ResDeleter {
-    void operator () (MYSQL_RES* res) {
-        mysql_free_result(res);
-    }
-};
-
 MySQL::MySQL():
     DBInterface(Type::mysql),
     connection(),
@@ -231,7 +227,11 @@ unsigned int MySQL::registerAccount(const std::string& login, const std::string&
     std::string h = hash;
     addAcc.bind(l.data(), MYSQL_TYPE_STRING);
     addAcc.bind(h.data(), MYSQL_TYPE_STRING);
+    try {
         addAcc.execute();
+    } catch (const Duplicate& dup) {
+        throw DuplicateLogin(dup.what());
+    }
 
     unsigned int id = lastInsertedId();
     static std::string defaultRole("default");
@@ -245,6 +245,24 @@ unsigned int MySQL::registerAccount(const std::string& login, const std::string&
     return id;
 }
 
+std::string MySQL::getAccountHash(const std::string& login) {
+    std::string l = login;
+    MYSQL* con = &connection;
+
+    Statement getHash(con, selectHash);
+    getHash.bind(l.data(), MYSQL_TYPE_STRING);
+    getHash.execute();
+
+    std::vector<std::vector<std::string>> result = getHash.fetchResult();
+    if (result.empty())
+        throw NoLogin("Couldn't find login " + l);
+
+    if (result[0].empty())
+        throw std::runtime_error("Error with the query \"selectHash\"");
+
+    return result[0][0];
+}
+
 unsigned int MySQL::lastInsertedId() {
     MYSQL* con = &connection;
     int result = mysql_query(con, lastIdQuery);

database/mysql/mysql.h

@@ -15,6 +15,8 @@
 class MySQL : public DBInterface {
     class Statement;
     class Transaction;
+
+
 public:
     MySQL();
     ~MySQL() override;
@@ -29,6 +31,7 @@ public:
     void setVersion(uint8_t version) override;
 
     unsigned int registerAccount(const std::string& login, const std::string& hash) override;
+    std::string getAccountHash(const std::string& login) override;
 
 private:
     void executeFile(const std::filesystem::path& relativePath);
@@ -40,4 +43,10 @@ protected:
     std::string login;
     std::string password;
     std::string database;
+
+struct ResDeleter {
+    void operator () (MYSQL_RES* res) {
+        mysql_free_result(res);
+    }
+};
 };

database/mysql/statement.cpp

@@ -5,6 +5,10 @@
 
 #include <cstring>
 
+#include "mysqld_error.h"
+
+#include "database/exceptions.h"
+
 static uint64_t TIME_LENGTH = sizeof(MYSQL_TIME);
 
 MySQL::Statement::Statement(MYSQL* connection, const char* statement):
@@ -44,11 +48,68 @@ void MySQL::Statement::bind(void* value, enum_field_types type, bool usigned) {
 }
 
 void MySQL::Statement::execute() {
-    int result = mysql_stmt_bind_param(stmt.get(), param.data());
+    MYSQL_STMT* raw = stmt.get();
+    int result = mysql_stmt_bind_param(raw, param.data());
     if (result != 0)
-        throw std::runtime_error(std::string("Error binding statement: ") + mysql_stmt_error(stmt.get()));
+        throw std::runtime_error(std::string("Error binding statement: ") + mysql_stmt_error(raw));
 
-    result = mysql_stmt_execute(stmt.get());
-    if (result != 0)
-        throw std::runtime_error(std::string("Error executing statement: ") + mysql_stmt_error(stmt.get()));
+    result = mysql_stmt_execute(raw);
+    if (result != 0) {
+        int errcode = mysql_stmt_errno(raw);
+        std::string text = mysql_stmt_error(raw);
+        switch (errcode) {
+            case ER_DUP_ENTRY:
+                throw Duplicate("Error executing statement: " + text);
+            default:
+                throw std::runtime_error("Error executing statement: " + text);
+        }
+    }
 }
+
+std::vector<std::vector<std::string>> MySQL::Statement::fetchResult() {
+    MYSQL_STMT* raw = stmt.get();
+    if (mysql_stmt_store_result(raw) != 0)
+        throw std::runtime_error(std::string("Error fetching statement result: ") + mysql_stmt_error(raw));   //TODO not sure if it's valid here
+
+    MYSQL_RES* meta = mysql_stmt_result_metadata(raw);
+    if (meta == nullptr)
+        throw std::runtime_error(std::string("Error fetching statement result: ") + mysql_stmt_error(raw));   //TODO not sure if it's valid here
+
+    std::unique_ptr<MYSQL_RES, ResDeleter> mt(meta);
+    unsigned int numColumns = mysql_num_fields(meta);
+    MYSQL_BIND bind[numColumns];
+    memset(bind, 0, sizeof(bind));
+
+    std::vector<std::string> line(numColumns);
+    std::vector<long unsigned int> lengths(numColumns);
+    for (unsigned int i = 0; i < numColumns; ++i) {
+        MYSQL_FIELD *field = mysql_fetch_field_direct(meta, i);
+
+        switch (field->type) {
+            case MYSQL_TYPE_STRING:
+            case MYSQL_TYPE_VAR_STRING:
+            case MYSQL_TYPE_VARCHAR:
+                break;
+            default:
+                throw std::runtime_error("Unsupported data fetching statement result " + std::to_string(field->type));
+        }
+        line[i].resize(field->length);
+        bind[i].buffer_type = field->type;
+        bind[i].buffer = line[i].data();
+        bind[i].buffer_length = field->length;
+        bind[i].length = &lengths[i];
+    }
+
+    if (mysql_stmt_bind_result(raw, bind) != 0)
+        throw std::runtime_error(std::string("Error binding on fetching statement result: ") + mysql_stmt_error(raw));
+
+    std::vector<std::vector<std::string>> result;
+    while (mysql_stmt_fetch(raw) == 0) {
+        std::vector<std::string>& row = result.emplace_back(numColumns);
+        for (unsigned int i = 0; i < numColumns; ++i)
+            row[i] = std::string(line[i].data(), lengths[i]);
+    }
+
+    return result;
+}
+

database/mysql/statement.h

@@ -18,6 +18,7 @@ public:
 
     void bind(void* value, enum_field_types type, bool usigned = false);
     void execute();
+    std::vector<std::vector<std::string>> fetchResult();
 
 private:
     std::unique_ptr<MYSQL_STMT, STMTDeleter> stmt;

database/mysql/transaction.cpp

@@ -1,3 +1,6 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
 #include "transaction.h"
 
 MySQL::Transaction::Transaction(MYSQL* connection):

database/mysql/transaction.h

@@ -1,3 +1,6 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
 #pragma once
 
 #include "mysql.h"

handler/CMakeLists.txt

@@ -3,6 +3,7 @@ set(HEADERS
     info.h
     env.h
     register.h
+    login.h
 )
 
 set(SOURCES
@@ -10,6 +11,7 @@ set(SOURCES
     info.cpp
     env.cpp
     register.cpp
+    login.cpp
 )
 
 target_sources(${PROJECT_NAME} PRIVATE ${SOURCES})

handler/env.cpp

@@ -11,7 +11,7 @@ void Handler::Env::handle(Request& request) {
     nlohmann::json body = nlohmann::json::object();
     request.printEnvironment(body);
 
-    Response res(request);
+    Response& res = request.createResponse();
     res.setBody(body);
     res.send();
 }

handler/env.h

@@ -7,10 +7,10 @@
 
 namespace Handler {
 
-class Env : public Handler::Handler {
+class Env : public Handler {
 public:
     Env();
-    virtual void handle(Request& request);
+    void handle(Request& request) override;
 
 };
 }

handler/info.cpp

@@ -8,7 +8,7 @@ Handler::Info::Info():
 {}
 
 void Handler::Info::handle(Request& request) {
-    Response res(request);
+    Response& res = request.createResponse();
     nlohmann::json body = nlohmann::json::object();
     body["type"] = PROJECT_NAME;
     body["version"] = PROJECT_VERSION;

handler/login.cpp

@@ -0,0 +1,65 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "login.h"
+
+#include "server/server.h"
+#include "database/exceptions.h"
+
+Handler::Login::Login(Server* server):
+    Handler("login", Request::Method::post),
+    server(server)
+{}
+
+void Handler::Login::handle(Request& request) {
+    std::map form = request.getForm();
+    std::map<std::string, std::string>::const_iterator itr = form.find("login");
+    if (itr == form.end())
+        return error(request, Result::noLogin, Response::Status::badRequest);
+
+    const std::string& login = itr->second;
+    if (login.empty())
+        return error(request, Result::emptyLogin, Response::Status::badRequest);
+
+    itr = form.find("password");
+    if (itr == form.end())
+        return error(request, Result::noPassword, Response::Status::badRequest);
+
+    const std::string& password = itr->second;
+    if (password.empty())
+        return error(request, Result::emptyPassword, Response::Status::badRequest);
+
+    bool success = false;
+    try {
+        success = server->validatePassword(login, password);
+    } catch (const DBInterface::NoLogin& e) {
+        std::cerr << "Exception on registration:\n\t" << e.what() << std::endl;
+        return error(request, Result::noLogin, Response::Status::badRequest); //can send unauthed instead, to exclude login spoofing
+    } catch (const std::exception& e) {
+        std::cerr << "Exception on registration:\n\t" << e.what() << std::endl;
+        return error(request, Result::unknownError, Response::Status::internalError);
+    }  catch (...) {
+        std::cerr << "Unknown exception on registration" << std::endl;
+        return error(request, Result::unknownError, Response::Status::internalError);
+    }
+    if (!success)
+        return error(request, Result::noLogin, Response::Status::badRequest);
+
+    //TODO opening the session
+
+    Response& res = request.createResponse();
+    nlohmann::json body = nlohmann::json::object();
+    body["result"] = Result::success;
+
+    res.setBody(body);
+    res.send();
+}
+
+void Handler::Login::error(Request& request, Result result, Response::Status code) {
+    Response& res = request.createResponse(code);
+    nlohmann::json body = nlohmann::json::object();
+    body["result"] = result;
+
+    res.setBody(body);
+    res.send();
+}

handler/login.h

@@ -0,0 +1,32 @@
+//  SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
+//  SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include "handler.h"
+
+class Server;
+namespace Handler {
+
+class Login : public Handler {
+public:
+    Login(Server* server);
+    void handle(Request& request) override;
+
+    enum class Result {
+        success,
+        noLogin,
+        emptyLogin,
+        noPassword,
+        emptyPassword,
+        unknownError
+    };
+
+private:
+    void error(Request& request, Result result, Response::Status code);
+
+private:
+    Server* server;
+};
+}
+

handler/register.cpp

@@ -4,6 +4,7 @@
 #include "register.h"
 
 #include "server/server.h"
+#include "database/exceptions.h"
 
 Handler::Register::Register(Server* server):
     Handler("register", Request::Method::post),
@@ -14,35 +15,38 @@ void Handler::Register::handle(Request& request) {
     std::map form = request.getForm();
     std::map<std::string, std::string>::const_iterator itr = form.find("login");
     if (itr == form.end())
-        return error(request, Result::noLogin);
+        return error(request, Result::noLogin, Response::Status::badRequest);
 
     const std::string& login = itr->second;
     if (login.empty())
-        return error(request, Result::emptyLogin);
+        return error(request, Result::emptyLogin, Response::Status::badRequest);
 
     //TODO login policies checkup
 
     itr = form.find("password");
     if (itr == form.end())
-        return error(request, Result::noPassword);
+        return error(request, Result::noPassword, Response::Status::badRequest);
 
     const std::string& password = itr->second;
     if (password.empty())
-        return error(request, Result::emptyPassword);
+        return error(request, Result::emptyPassword, Response::Status::badRequest);
 
     //TODO password policies checkup
 
     try {
         server->registerAccount(login, password);
+    } catch (const DBInterface::DuplicateLogin& e) {
+        std::cerr << "Exception on registration:\n\t" << e.what() << std::endl;
+        return error(request, Result::loginExists, Response::Status::conflict);
     } catch (const std::exception& e) {
         std::cerr << "Exception on registration:\n\t" << e.what() << std::endl;
-        return error(request, Result::unknownError);
+        return error(request, Result::unknownError, Response::Status::internalError);
     }  catch (...) {
         std::cerr << "Unknown exception on registration" << std::endl;
-        return error(request, Result::unknownError);
+        return error(request, Result::unknownError, Response::Status::internalError);
     }
 
-    Response res(request);
+    Response& res = request.createResponse();
     nlohmann::json body = nlohmann::json::object();
     body["result"] = Result::success;
 
@@ -50,8 +54,8 @@ void Handler::Register::handle(Request& request) {
     res.send();
 }
 
-void Handler::Register::error(Request& request, Result result) {
-    Response res(request);
+void Handler::Register::error(Request& request, Result result, Response::Status code) {
+    Response& res = request.createResponse(code);
     nlohmann::json body = nlohmann::json::object();
     body["result"] = result;
 

handler/register.h

@@ -8,10 +8,10 @@
 class Server;
 namespace Handler {
 
-class Register : public Handler::Handler {
+class Register : public Handler {
 public:
     Register(Server* server);
-    virtual void handle(Request& request);
+    void handle(Request& request) override;
 
     enum class Result {
         success,
@@ -26,7 +26,7 @@ public:
     };
 
 private:
-    void error(Request& request, Result result);
+    void error(Request& request, Result result, Response::Status code);
 
 private:
     Server* server;

request/request.cpp

@@ -5,8 +5,6 @@
 
 #include "response/response.h"
 
-constexpr static const char* GET("GET");
-
 constexpr static const char* REQUEST_METHOD("REQUEST_METHOD");
 constexpr static const char* SCRIPT_FILENAME("SCRIPT_FILENAME");
 constexpr static const char* SERVER_NAME("SERVER_NAME");
@@ -51,11 +49,15 @@ void Request::terminate() {
     }
 }
 
-Request::Method Request::method() const {
+std::string_view Request::methodName() const {
     if (state == State::initial)
         throw std::runtime_error("An attempt to read request method on not accepted request");
 
-    std::string_view method(FCGX_GetParam(REQUEST_METHOD, raw.envp));
+    return FCGX_GetParam(REQUEST_METHOD, raw.envp);
+}
+
+Request::Method Request::method() const {
+    std::string_view method =  methodName();
     for (const auto& pair : methods) {
         if (pair.first == method)
             return pair.second;
@@ -79,17 +81,42 @@ bool Request::wait(int socketDescriptor) {
     return result;
 }
 
-OStream Request::getOutputStream(const Response* response) {
-    validateResponse(response);
+OStream Request::getOutputStream() {
     return OStream(raw.out);
 }
 
-OStream Request::getErrorStream(const Response* response) {
-    validateResponse(response);
+OStream Request::getErrorStream() {
     return OStream(raw.err);
 }
 
-void Request::responseIsComplete(const Response* response) {
+Response& Request::createResponse() {
+    if (state != State::accepted)
+        throw std::runtime_error("An attempt create response to the request in the wrong state");
+
+    response = std::unique_ptr<Response>(new Response(*this));
+    state = State::responding;
+
+    return *response.get();
+}
+
+Response& Request::createResponse(Response::Status status) {
+    if (state != State::accepted)
+        throw std::runtime_error("An attempt create response to the request in the wrong state");
+
+    response = std::unique_ptr<Response>(new Response(*this, status));
+    state = State::responding;
+
+    return *response.get();
+}
+
+uint16_t Request::responseCode() const {
+    if (state != State::responded)
+        throw std::runtime_error("An attempt create read response code on the wrong state");
+
+    return response->statusCode();
+}
+
+void Request::responseIsComplete() {
     switch (state) {
         case State::initial:
             throw std::runtime_error("An attempt to mark the request as complete, but it wasn't even accepted yet");
@@ -98,10 +125,6 @@ void Request::responseIsComplete(const Response* response) {
             throw std::runtime_error("An attempt to mark the request as complete, but it wasn't responded");
             break;
         case State::responding:
-            if (Request::response != response)
-                throw std::runtime_error("An attempt to mark the request as complete by the different response who actually started responding");
-
-            Request::response = nullptr;
             state = State::responded;
             break;
         case State::responded:
@@ -110,26 +133,6 @@ void Request::responseIsComplete(const Response* response) {
     }
 }
 
-void Request::validateResponse(const Response* response) {
-    switch (state) {
-        case State::initial:
-            throw std::runtime_error("An attempt to request stream while the request wasn't even accepted yet");
-            break;
-        case State::accepted:
-            Request::response = response;
-            state = State::responding;
-            break;
-        case State::responding:
-            if (Request::response != response)
-                throw std::runtime_error("Error handling a request: first time one response started replying, then another continued");
-
-            break;
-        case State::responded:
-            throw std::runtime_error("An attempt to request stream on a request that was already done responding");
-            break;
-    }
-}
-
 Request::State Request::currentState() const {
     return state;
 }

request/request.h

@@ -16,9 +16,10 @@
 
 #include "stream/ostream.h"
 #include "utils/formdecode.h"
+#include "response/response.h"
 
-class Response;
 class Request {
+    friend class Response;
 public:
     enum class State {
         initial,
@@ -43,26 +44,29 @@ public:
     bool wait(int socketDescriptor);
     void terminate();
 
+    Response& createResponse();
+    Response& createResponse(Response::Status status);
+
+    uint16_t responseCode() const;
     Method method() const;
+    std::string_view methodName() const;
     State currentState() const;
     bool isFormUrlEncoded() const;
     unsigned int contentLength() const;
     std::map<std::string, std::string> getForm() const;
 
-    OStream getOutputStream(const Response* response);
-    OStream getErrorStream(const Response* response);
-    void responseIsComplete(const Response* response);
-
     std::string getPath(const std::string& serverName) const;
     std::string getServerName() const;
     void printEnvironment(std::ostream& out);
     void printEnvironment(nlohmann::json& out);
 
 private:
-    void validateResponse(const Response* response);
+    OStream getOutputStream();
+    OStream getErrorStream();
+    void responseIsComplete();
 
 private:
     State state;
     FCGX_Request raw;
-    const Response* response;
+    std::unique_ptr<Response> response;
 };

response/response.cpp

@@ -3,10 +3,25 @@
 
 #include "response.h"
 
-constexpr std::array<std::string_view, static_cast<uint8_t>(Response::Status::__size)> statusCodes = {
+#include "request/request.h"
+
+constexpr std::array<uint16_t, static_cast<uint8_t>(Response::Status::__size)> statusCodes = {
+    200,
+    400,
+    401,
+    404,
+    405,
+    409,
+    500
+};
+
+constexpr std::array<std::string_view, static_cast<uint8_t>(Response::Status::__size)> statuses = {
     "Status: 200 OK",
+    "Status: 400 Bad Request",
+    "Status: 401 Unauthorized",
     "Status: 404 Not Found",
     "Status: 405 Method Not Allowed",
+    "Status: 409 Conflict",
     "Status: 500 Internal Error"
 };
 
@@ -33,9 +48,9 @@ void Response::send() const {
     // OStream out = status == Status::ok ?
     //     request.getOutputStream() :
     //     request.getErrorStream();
-    OStream out = request.getOutputStream(this);
+    OStream out = request.getOutputStream();
 
-    out << statusCodes[static_cast<uint8_t>(status)];
+    out << statuses[static_cast<uint8_t>(status)];
     if (!body.empty())
         out << '\n'
         << contentTypes[static_cast<uint8_t>(type)]
@@ -43,7 +58,11 @@ void Response::send() const {
         << '\n'
         << body;
 
-    request.responseIsComplete(this);
+    request.responseIsComplete();
+}
+
+uint16_t Response::statusCode() const {
+    return statusCodes[static_cast<uint8_t>(status)];
 }
 
 void Response::setBody(const std::string& body) {

response/response.h

@@ -9,15 +9,20 @@
 
 #include <nlohmann/json.hpp>
 
-#include "request/request.h"
 #include "stream/ostream.h"
 
+class Request;
 class Response {
+    friend class Request;
+
 public:
     enum class Status {
         ok,
+        badRequest,
+        unauthorized,
         notFound,
         methodNotAllowed,
+        conflict,
         internalError,
         __size
     };
@@ -27,13 +32,17 @@ public:
         json,
         __size
     };
-    Response(Request& request);
-    Response(Request& request, Status status);
+
+    uint16_t statusCode() const;
 
     void send() const;
     void setBody(const std::string& body);
     void setBody(const nlohmann::json& body);
 
+private:
+    Response(Request& request);
+    Response(Request& request, Status status);
+
 private:
     Request& request;
     Status status;

server/router.cpp

@@ -50,29 +50,29 @@ void Router::route(const std::string& path, std::unique_ptr<Request> request) {
         if (request->currentState() != Request::State::responded)
             handleInternalError(path, std::runtime_error("handler failed to handle the request"), std::move(request));
         else
-            std::cout << "Success:\t" << path << std::endl;
+            std::cout << request->responseCode() << '\t' << request->methodName() << '\t' << path << std::endl;
     } catch (const std::exception& e) {
         handleInternalError(path, e, std::move(request));
     }
 }
 
 void Router::handleNotFound(const std::string& path, std::unique_ptr<Request> request) {
-    Response notFound(*request.get(), Response::Status::notFound);
+    Response& notFound = request->createResponse(Response::Status::notFound);
     notFound.setBody(std::string("Path \"") + path + "\" was not found");
     notFound.send();
-    std::cerr << "Not found:\t" << path << std::endl;
+    std::cerr << notFound.statusCode() << '\t' << request->methodName() << '\t' << path << std::endl;
 }
 
 void Router::handleInternalError(const std::string& path, const std::exception& exception, std::unique_ptr<Request> request) {
-    Response error(*request.get(), Response::Status::internalError);
+    Response& error = request->createResponse(Response::Status::internalError);
     error.setBody(std::string(exception.what()));
     error.send();
-    std::cerr << "Internal error:\t" << path << "\n\t" << exception.what() << std::endl;
+    std::cerr << error.statusCode() << '\t' << request->methodName() << '\t' << path << std::endl;
 }
 
 void Router::handleMethodNotAllowed(const std::string& path, std::unique_ptr<Request> request) {
-    Response error(*request.get(), Response::Status::methodNotAllowed);
+    Response& error = request->createResponse(Response::Status::methodNotAllowed);
     error.setBody(std::string("Method not allowed"));
     error.send();
-    std::cerr << "Method not allowed:\t" << path << std::endl;
+    std::cerr << error.statusCode() << '\t' << request->methodName() << '\t' << path << std::endl;
 }

server/server.cpp

@@ -8,6 +8,7 @@
 #include "handler/info.h"
 #include "handler/env.h"
 #include "handler/register.h"
+#include "handler/login.h"
 
 constexpr const char* pepper = "well, not much of a secret, huh?";
 constexpr uint8_t currentDbVesion = 1;
@@ -39,6 +40,7 @@ Server::Server():
     router.addRoute(std::make_unique<Handler::Info>());
     router.addRoute(std::make_unique<Handler::Env>());
     router.addRoute(std::make_unique<Handler::Register>(this));
+    router.addRoute(std::make_unique<Handler::Login>(this));
 }
 
 Server::~Server() {}
@@ -63,7 +65,7 @@ void Server::handleRequest(std::unique_ptr<Request> request) {
             std::cout << "received server name " << serverName.value() << std::endl;
         } catch (...) {
             std::cerr << "failed to read server name" << std::endl;
-            Response error(*request.get(), Response::Status::internalError);
+            Response& error = request->createResponse(Response::Status::internalError);
             error.send();
             return;
         }
@@ -107,3 +109,19 @@ unsigned int Server::registerAccount(const std::string& login, const std::string
 
     return db->registerAccount(login, hash);
 }
+
+bool Server::validatePassword(const std::string& login, const std::string& password) {
+    std::string hash = db->getAccountHash(login);
+
+    std::string spiced = password + pepper;
+    int result = argon2id_verify(hash.data(), spiced.data(), spiced.size());
+
+    switch (result) {
+        case ARGON2_OK:
+            return true;
+        case ARGON2_VERIFY_MISMATCH:
+            return false;
+        default:
+            throw std::runtime_error(std::string("Failed to verify password: ") + argon2_error_message(result));
+    }
+}

server/server.h

@@ -32,6 +32,7 @@ public:
     void run(int socketDescriptor);
 
     unsigned int registerAccount(const std::string& login, const std::string& password);
+    bool validatePassword(const std::string& login, const std::string& password);
 
 private:
     void handleRequest(std::unique_ptr<Request> request);