#include "serverauthentication.h" #include "shared/exploit_fixes/ns_limits.h" #include "core/convar/cvar.h" #include "core/convar/convar.h" #include "masterserver/masterserver.h" #include "server/serverpresence.h" #include "engine/hoststate.h" #include "bansystem.h" #include "core/convar/concommand.h" #include "dedicated/dedicated.h" #include "config/profile.h" #include "core/tier0.h" #include "engine/r2engine.h" #include "client/r2client.h" #include "server/r2server.h" #include <fstream> #include <filesystem> #include <string> #include <thread> AUTOHOOK_INIT() // global vars ServerAuthenticationManager* g_pServerAuthentication; CBaseServer__RejectConnectionType CBaseServer__RejectConnection; void ServerAuthenticationManager::AddRemotePlayer(std::string token, uint64_t uid, std::string username, std::string pdata) { std::string uidS = std::to_string(uid); RemoteAuthData newAuthData {}; strncpy_s(newAuthData.uid, sizeof(newAuthData.uid), uidS.c_str(), uidS.length()); strncpy_s(newAuthData.username, sizeof(newAuthData.username), username.c_str(), username.length()); newAuthData.pdata = new char[pdata.length()]; newAuthData.pdataSize = pdata.length(); memcpy(newAuthData.pdata, pdata.c_str(), newAuthData.pdataSize); std::lock_guard<std::mutex> guard(m_AuthDataMutex); m_RemoteAuthenticationData[token] = newAuthData; } void ServerAuthenticationManager::AddPlayer(CBaseClient* pPlayer, const char* pToken) { PlayerAuthenticationData additionalData; auto remoteAuthData = m_RemoteAuthenticationData.find(pToken); if (remoteAuthData != m_RemoteAuthenticationData.end()) additionalData.pdataSize = remoteAuthData->second.pdataSize; else additionalData.pdataSize = PERSISTENCE_MAX_SIZE; additionalData.usingLocalPdata = pPlayer->m_iPersistenceReady == ePersistenceReady::READY_INSECURE; m_PlayerAuthenticationData.insert(std::make_pair(pPlayer, additionalData)); } void ServerAuthenticationManager::RemovePlayer(CBaseClient* pPlayer) { if (m_PlayerAuthenticationData.count(pPlayer)) m_PlayerAuthenticationData.erase(pPlayer); } bool ServerAuthenticationManager::VerifyPlayerName(const char* pAuthToken, const char* pName, char pOutVerifiedName[64]) { std::lock_guard<std::mutex> guard(m_AuthDataMutex); // always use name from masterserver if available // use of strncpy_s here should verify that this is always nullterminated within valid buffer size auto authData = m_RemoteAuthenticationData.find(pAuthToken); if (authData != m_RemoteAuthenticationData.end() && *authData->second.username) strncpy_s(pOutVerifiedName, 64, authData->second.username, 63); else strncpy_s(pOutVerifiedName, 64, pName, 63); // now, check that whatever name we have is actually valid // first, make sure it's >1 char if (!*pOutVerifiedName) return false; // next, make sure it's within a valid range of ascii characters for (int i = 0; pOutVerifiedName[i]; i++) { if (pOutVerifiedName[i] < 32 || pOutVerifiedName[i] > 126) return false; } return true; } bool ServerAuthenticationManager::IsDuplicateAccount(CBaseClient* pPlayer, const char* pPlayerUid) { if (m_bAllowDuplicateAccounts) return false; bool bHasUidPlayer = false; for (int i = 0; i < g_pGlobals->m_nMaxClients; i++) if (&g_pClientArray[i] != pPlayer && !strcmp(pPlayerUid, g_pClientArray[i].m_UID)) return true; return false; } bool ServerAuthenticationManager::CheckAuthentication(CBaseClient* pPlayer, uint64_t iUid, char* pAuthToken) { std::string sUid = std::to_string(iUid); // check whether this player's authentication is valid but don't actually write anything to the player, we'll do that later // if we don't need auth this is valid if (Cvar_ns_auth_allow_insecure->GetBool()) return true; // local server that doesn't need auth (probably sp) and local player if (m_bStartingLocalSPGame && !strcmp(sUid.c_str(), g_pLocalPlayerUserID)) return true; // don't allow duplicate accounts if (IsDuplicateAccount(pPlayer, sUid.c_str())) return false; std::lock_guard<std::mutex> guard(m_AuthDataMutex); auto authData = m_RemoteAuthenticationData.find(pAuthToken); if (authData != m_RemoteAuthenticationData.end() && !strcmp(sUid.c_str(), authData->second.uid)) return true; return false; } void ServerAuthenticationManager::AuthenticatePlayer(CBaseClient* pPlayer, uint64_t iUid, char* pAuthToken) { // for bot players, generate a new uid if (pPlayer->m_bFakePlayer) iUid = 0; // is this a good way of doing things :clueless: std::string sUid = std::to_string(iUid); // copy uuid strcpy(pPlayer->m_UID, sUid.c_str()); std::lock_guard<std::mutex> guard(m_AuthDataMutex); auto authData = m_RemoteAuthenticationData.find(pAuthToken); if (authData != m_RemoteAuthenticationData.end()) { // if we're resetting let script handle the reset with InitPersistentData() on connect if (!m_bForceResetLocalPlayerPersistence || strcmp(sUid.c_str(), g_pLocalPlayerUserID)) { // copy pdata into buffer memcpy(pPlayer->m_PersistenceBuffer, authData->second.pdata, authData->second.pdataSize); } // set persistent data as ready pPlayer->m_iPersistenceReady = ePersistenceReady::READY_REMOTE; } // we probably allow insecure at this point, but make sure not to write anyway if not insecure else if (Cvar_ns_auth_allow_insecure->GetBool() || pPlayer->m_bFakePlayer) { // set persistent data as ready // note: actual placeholder persistent data is populated in script with InitPersistentData() pPlayer->m_iPersistenceReady = ePersistenceReady::READY_INSECURE; } } bool ServerAuthenticationManager::RemovePlayerAuthData(CBaseClient* pPlayer) { if (!Cvar_ns_erase_auth_info->GetBool()) // keep auth data forever return false; // hack for special case where we're on a local server, so we erase our own newly created auth data on disconnect if (m_bNeedLocalAuthForNewgame && !strcmp(pPlayer->m_UID, g_pLocalPlayerUserID)) return false; // we don't have our auth token at this point, so lookup authdata by uid for (auto& auth : m_RemoteAuthenticationData) { if (!strcmp(pPlayer->m_UID, auth.second.uid)) { // pretty sure this is fine, since we don't iterate after the erase // i think if we iterated after it'd be undefined behaviour tho std::lock_guard<std::mutex> guard(m_AuthDataMutex); delete[] auth.second.pdata; m_RemoteAuthenticationData.erase(auth.first); return true; } } return false; } void ServerAuthenticationManager::WritePersistentData(CBaseClient* pPlayer) { if (pPlayer->m_iPersistenceReady == ePersistenceReady::READY_REMOTE) { g_pMasterServerManager->WritePlayerPersistentData( pPlayer->m_UID, (const char*)pPlayer->m_PersistenceBuffer, m_PlayerAuthenticationData[pPlayer].pdataSize); } else if (Cvar_ns_auth_allow_insecure_write->GetBool()) { // todo: write pdata to disk here } } // auth hooks // store these in vars so we can use them in CBaseClient::Connect // this is fine because ptrs won't decay by the time we use this, just don't use it outside of calls from cbaseclient::connectclient char* pNextPlayerToken; uint64_t iNextPlayerUid; // clang-format off AUTOHOOK(CBaseServer__ConnectClient, engine.dll + 0x114430, void*,, ( void* self, void* addr, void* a3, uint32_t a4, uint32_t a5, int32_t a6, void* a7, char* playerName, char* serverFilter, void* a10, char a11, void* a12, char a13, char a14, int64_t uid, uint32_t a16, uint32_t a17)) // clang-format on { // auth tokens are sent with serverfilter, can't be accessed from player struct to my knowledge, so have to do this here pNextPlayerToken = serverFilter; iNextPlayerUid = uid; return CBaseServer__ConnectClient(self, addr, a3, a4, a5, a6, a7, playerName, serverFilter, a10, a11, a12, a13, a14, uid, a16, a17); } ConVar* Cvar_ns_allowuserclantags; // clang-format off AUTOHOOK(CBaseClient__Connect, engine.dll + 0x101740, bool,, (CBaseClient* self, char* pName, void* pNetChannel, char bFakePlayer, void* a5, char pDisconnectReason[256], void* a7)) // clang-format on { const char* pAuthenticationFailure = nullptr; char pVerifiedName[64]; if (!bFakePlayer) { if (!g_pServerAuthentication->VerifyPlayerName(pNextPlayerToken, pName, pVerifiedName)) pAuthenticationFailure = "Invalid Name."; else if (!g_pBanSystem->IsUIDAllowed(iNextPlayerUid)) pAuthenticationFailure = "Banned From server."; else if (!g_pServerAuthentication->CheckAuthentication(self, iNextPlayerUid, pNextPlayerToken)) pAuthenticationFailure = "Authentication Failed."; } else // need to copy name for bots still strncpy_s(pVerifiedName, pName, 63); if (pAuthenticationFailure) { spdlog::info("{}'s (uid {}) connection was rejected: \"{}\"", pName, iNextPlayerUid, pAuthenticationFailure); strncpy_s(pDisconnectReason, 256, pAuthenticationFailure, 255); return false; } // try to actually connect the player if (!CBaseClient__Connect(self, pVerifiedName, pNetChannel, bFakePlayer, a5, pDisconnectReason, a7)) return false; // we already know this player's authentication data is legit, actually write it to them now g_pServerAuthentication->AuthenticatePlayer(self, iNextPlayerUid, pNextPlayerToken); g_pServerAuthentication->AddPlayer(self, pNextPlayerToken); g_pServerLimits->AddPlayer(self); return true; } // clang-format off AUTOHOOK(CBaseClient__ActivatePlayer, engine.dll + 0x100F80, void,, (CBaseClient* self)) // clang-format on { // if we're authed, write our persistent data // RemovePlayerAuthData returns true if it removed successfully, i.e. on first call only, and we only want to write on >= second call // (since this func is called on map loads) if (self->m_iPersistenceReady >= ePersistenceReady::READY && !g_pServerAuthentication->RemovePlayerAuthData(self)) { g_pServerAuthentication->m_bForceResetLocalPlayerPersistence = false; g_pServerAuthentication->WritePersistentData(self); g_pServerPresence->SetPlayerCount(g_pServerAuthentication->m_PlayerAuthenticationData.size()); } CBaseClient__ActivatePlayer(self); } // clang-format off AUTOHOOK(_CBaseClient__Disconnect, engine.dll + 0x1012C0, void,, (CBaseClient* self, uint32_t unknownButAlways1, const char* pReason, ...)) // clang-format on { // have to manually format message because can't pass varargs to original func char buf[1024]; va_list va; va_start(va, pReason); vsprintf(buf, pReason, va); va_end(va); // this reason is used while connecting to a local server, hacky, but just ignore it if (strcmp(pReason, "Connection closing")) { spdlog::info("Player {} disconnected: \"{}\"", self->m_Name, buf); // dcing, write persistent data if (g_pServerAuthentication->m_PlayerAuthenticationData[self].needPersistenceWriteOnLeave) g_pServerAuthentication->WritePersistentData(self); memset(self->m_PersistenceBuffer, 0, g_pServerAuthentication->m_PlayerAuthenticationData[self].pdataSize); g_pServerAuthentication->RemovePlayerAuthData(self); // won't do anything 99% of the time, but just in case g_pServerAuthentication->RemovePlayer(self); g_pServerLimits->RemovePlayer(self); } g_pServerPresence->SetPlayerCount(g_pServerAuthentication->m_PlayerAuthenticationData.size()); _CBaseClient__Disconnect(self, unknownButAlways1, buf); } void ConCommand_ns_resetpersistence(const CCommand& args) { if (*g_pServerState == server_state_t::ss_active) { spdlog::error("ns_resetpersistence must be entered from the main menu"); return; } spdlog::info("resetting persistence on next lobby load..."); g_pServerAuthentication->m_bForceResetLocalPlayerPersistence = true; } ON_DLL_LOAD_RELIESON("engine.dll", ServerAuthentication, (ConCommand, ConVar), (CModule module)) { AUTOHOOK_DISPATCH() g_pServerAuthentication = new ServerAuthenticationManager; g_pServerAuthentication->Cvar_ns_erase_auth_info = new ConVar("ns_erase_auth_info", "1", FCVAR_GAMEDLL, "Whether auth info should be erased from this server on disconnect or crash"); g_pServerAuthentication->Cvar_ns_auth_allow_insecure = new ConVar("ns_auth_allow_insecure", "0", FCVAR_GAMEDLL, "Whether this server will allow unauthenicated players to connect"); g_pServerAuthentication->Cvar_ns_auth_allow_insecure_write = new ConVar( "ns_auth_allow_insecure_write", "0", FCVAR_GAMEDLL, "Whether the pdata of unauthenticated clients will be written to disk when changed"); RegisterConCommand( "ns_resetpersistence", ConCommand_ns_resetpersistence, "resets your pdata when you next enter the lobby", FCVAR_NONE); // patch to disable kicking based on incorrect serverfilter in connectclient, since we repurpose it for use as an auth token module.Offset(0x114655).Patch("EB"); // patch to disable fairfight marking players as cheaters and kicking them module.Offset(0x101012).Patch("E9 90 00"); CBaseServer__RejectConnection = module.Offset(0x1182E0).RCast<CBaseServer__RejectConnectionType>(); if (CommandLine()->CheckParm("-allowdupeaccounts")) { // patch to allow same of multiple account module.Offset(0x114510).Patch("EB"); g_pServerAuthentication->m_bAllowDuplicateAccounts = true; } }