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path: root/NorthstarDLL/shared/exploit_fixes/ns_limits.cpp
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-rw-r--r--NorthstarDLL/shared/exploit_fixes/ns_limits.cpp298
1 files changed, 298 insertions, 0 deletions
diff --git a/NorthstarDLL/shared/exploit_fixes/ns_limits.cpp b/NorthstarDLL/shared/exploit_fixes/ns_limits.cpp
new file mode 100644
index 00000000..49f80bab
--- /dev/null
+++ b/NorthstarDLL/shared/exploit_fixes/ns_limits.cpp
@@ -0,0 +1,298 @@
+#include "pch.h"
+#include "ns_limits.h"
+#include "engine/hoststate.h"
+#include "client/r2client.h"
+#include "engine/r2engine.h"
+#include "server/r2server.h"
+#include "shared/maxplayers.h"
+#include "core/tier0.h"
+#include "core/math/vector.h"
+#include "server/auth/serverauthentication.h"
+
+AUTOHOOK_INIT()
+
+ServerLimitsManager* g_pServerLimits;
+
+// todo: make this work on higher timescales, also possibly disable when sv_cheats is set
+void ServerLimitsManager::RunFrame(double flCurrentTime, float flFrameTime)
+{
+ if (Cvar_sv_antispeedhack_enable->GetBool())
+ {
+ // for each player, set their usercmd processing budget for the frame to the last frametime for the server
+ for (int i = 0; i < R2::GetMaxPlayers(); i++)
+ {
+ R2::CBaseClient* player = &R2::g_pClientArray[i];
+
+ if (m_PlayerLimitData.find(player) != m_PlayerLimitData.end())
+ {
+ PlayerLimitData* pLimitData = &g_pServerLimits->m_PlayerLimitData[player];
+ if (pLimitData->flFrameUserCmdBudget < 0.016666667 * Cvar_sv_antispeedhack_maxtickbudget->GetFloat())
+ pLimitData->flFrameUserCmdBudget +=
+ fmax(flFrameTime, 0.016666667) * g_pServerLimits->Cvar_sv_antispeedhack_budgetincreasemultiplier->GetFloat();
+ }
+ }
+ }
+}
+
+void ServerLimitsManager::AddPlayer(R2::CBaseClient* player)
+{
+ PlayerLimitData limitData;
+ limitData.flFrameUserCmdBudget = 0.016666667 * Cvar_sv_antispeedhack_maxtickbudget->GetFloat();
+
+ m_PlayerLimitData.insert(std::make_pair(player, limitData));
+}
+
+void ServerLimitsManager::RemovePlayer(R2::CBaseClient* player)
+{
+ if (m_PlayerLimitData.find(player) != m_PlayerLimitData.end())
+ m_PlayerLimitData.erase(player);
+}
+
+bool ServerLimitsManager::CheckStringCommandLimits(R2::CBaseClient* player)
+{
+ if (CVar_sv_quota_stringcmdspersecond->GetInt() != -1)
+ {
+ // note: this isn't super perfect, legit clients can trigger it in lobby if they try, mostly good enough tho imo
+ if (Tier0::Plat_FloatTime() - m_PlayerLimitData[player].lastClientCommandQuotaStart >= 1.0)
+ {
+ // reset quota
+ m_PlayerLimitData[player].lastClientCommandQuotaStart = Tier0::Plat_FloatTime();
+ m_PlayerLimitData[player].numClientCommandsInQuota = 0;
+ }
+
+ m_PlayerLimitData[player].numClientCommandsInQuota++;
+ if (m_PlayerLimitData[player].numClientCommandsInQuota > CVar_sv_quota_stringcmdspersecond->GetInt())
+ {
+ // too many stringcmds, dc player
+ return false;
+ }
+ }
+
+ return true;
+}
+
+bool ServerLimitsManager::CheckChatLimits(R2::CBaseClient* player)
+{
+ if (Tier0::Plat_FloatTime() - m_PlayerLimitData[player].lastSayTextLimitStart >= 1.0)
+ {
+ m_PlayerLimitData[player].lastSayTextLimitStart = Tier0::Plat_FloatTime();
+ m_PlayerLimitData[player].sayTextLimitCount = 0;
+ }
+
+ if (m_PlayerLimitData[player].sayTextLimitCount >= Cvar_sv_max_chat_messages_per_sec->GetInt())
+ return false;
+
+ m_PlayerLimitData[player].sayTextLimitCount++;
+ return true;
+}
+
+// clang-format off
+AUTOHOOK(CNetChan__ProcessMessages, engine.dll + 0x2140A0,
+char, __fastcall, (void* self, void* buf))
+// clang-format on
+{
+ enum eNetChanLimitMode
+ {
+ NETCHANLIMIT_WARN,
+ NETCHANLIMIT_KICK
+ };
+
+ double startTime = Tier0::Plat_FloatTime();
+ char ret = CNetChan__ProcessMessages(self, buf);
+
+ // check processing limits, unless we're in a level transition
+ if (R2::g_pHostState->m_iCurrentState == R2::HostState_t::HS_RUN && Tier0::ThreadInServerFrameThread())
+ {
+ // player that sent the message
+ R2::CBaseClient* sender = *(R2::CBaseClient**)((char*)self + 368);
+
+ // if no sender, return
+ // relatively certain this is fine?
+ if (!sender || !g_pServerLimits->m_PlayerLimitData.count(sender))
+ return ret;
+
+ // reset every second
+ if (startTime - g_pServerLimits->m_PlayerLimitData[sender].lastNetChanProcessingLimitStart >= 1.0 ||
+ g_pServerLimits->m_PlayerLimitData[sender].lastNetChanProcessingLimitStart == -1.0)
+ {
+ g_pServerLimits->m_PlayerLimitData[sender].lastNetChanProcessingLimitStart = startTime;
+ g_pServerLimits->m_PlayerLimitData[sender].netChanProcessingLimitTime = 0.0;
+ }
+ g_pServerLimits->m_PlayerLimitData[sender].netChanProcessingLimitTime += (Tier0::Plat_FloatTime() * 1000) - (startTime * 1000);
+
+ if (g_pServerLimits->m_PlayerLimitData[sender].netChanProcessingLimitTime >=
+ g_pServerLimits->Cvar_net_chan_limit_msec_per_sec->GetInt())
+ {
+ spdlog::warn(
+ "Client {} hit netchan processing limit with {}ms of processing time this second (max is {})",
+ (char*)sender + 0x16,
+ g_pServerLimits->m_PlayerLimitData[sender].netChanProcessingLimitTime,
+ g_pServerLimits->Cvar_net_chan_limit_msec_per_sec->GetInt());
+
+ // never kick local player
+ if (g_pServerLimits->Cvar_net_chan_limit_mode->GetInt() != NETCHANLIMIT_WARN && strcmp(R2::g_pLocalPlayerUserID, sender->m_UID))
+ {
+ R2::CBaseClient__Disconnect(sender, 1, "Exceeded net channel processing limit");
+ return false;
+ }
+ }
+ }
+
+ return ret;
+}
+
+// clang-format off
+AUTOHOOK(ProcessConnectionlessPacket, engine.dll + 0x117800,
+bool, , (void* a1, R2::netpacket_t* packet))
+// clang-format on
+{
+ static const ConVar* Cvar_net_data_block_enabled = R2::g_pCVar->FindVar("net_data_block_enabled");
+
+ // don't ratelimit datablock packets as long as datablock is enabled
+ if (packet->adr.type == R2::NA_IP &&
+ (!(packet->data[4] == 'N' && Cvar_net_data_block_enabled->GetBool()) || !Cvar_net_data_block_enabled->GetBool()))
+ {
+ // bad lookup: optimise later tm
+ UnconnectedPlayerLimitData* sendData = nullptr;
+ for (UnconnectedPlayerLimitData& foundSendData : g_pServerLimits->m_UnconnectedPlayerLimitData)
+ {
+ if (!memcmp(packet->adr.ip, foundSendData.ip, 16))
+ {
+ sendData = &foundSendData;
+ break;
+ }
+ }
+
+ if (!sendData)
+ {
+ sendData = &g_pServerLimits->m_UnconnectedPlayerLimitData.emplace_back();
+ memcpy(sendData->ip, packet->adr.ip, 16);
+ }
+
+ if (Tier0::Plat_FloatTime() < sendData->timeoutEnd)
+ return false;
+
+ if (Tier0::Plat_FloatTime() - sendData->lastQuotaStart >= 1.0)
+ {
+ sendData->lastQuotaStart = Tier0::Plat_FloatTime();
+ sendData->packetCount = 0;
+ }
+
+ sendData->packetCount++;
+
+ if (sendData->packetCount >= g_pServerLimits->Cvar_sv_querylimit_per_sec->GetInt())
+ {
+ spdlog::warn(
+ "Client went over connectionless ratelimit of {} per sec with packet of type {}",
+ g_pServerLimits->Cvar_sv_querylimit_per_sec->GetInt(),
+ packet->data[4]);
+
+ // timeout for a minute
+ sendData->timeoutEnd = Tier0::Plat_FloatTime() + 60.0;
+ return false;
+ }
+ }
+
+ return ProcessConnectionlessPacket(a1, packet);
+}
+
+// this is weird and i'm not sure if it's correct, so not using for now
+/*AUTOHOOK(CBasePlayer__PhysicsSimulate, server.dll + 0x5A6E50, bool, __fastcall, (void* self, int a2, char a3))
+{
+ spdlog::info("CBasePlayer::PhysicsSimulate");
+ return CBasePlayer__PhysicsSimulate(self, a2, a3);
+}*/
+
+struct alignas(4) SV_CUserCmd
+{
+ DWORD command_number;
+ DWORD tick_count;
+ float command_time;
+ Vector3 worldViewAngles;
+ BYTE gap18[4];
+ Vector3 localViewAngles;
+ Vector3 attackangles;
+ Vector3 move;
+ DWORD buttons;
+ BYTE impulse;
+ short weaponselect;
+ DWORD meleetarget;
+ BYTE gap4C[24];
+ char headoffset;
+ BYTE gap65[11];
+ Vector3 cameraPos;
+ Vector3 cameraAngles;
+ BYTE gap88[4];
+ int tickSomething;
+ DWORD dword90;
+ DWORD predictedServerEventAck;
+ DWORD dword98;
+ float frameTime;
+};
+
+// clang-format off
+AUTOHOOK(CPlayerMove__RunCommand, server.dll + 0x5B8100,
+void, __fastcall, (void* self, R2::CBasePlayer* player, SV_CUserCmd* pUserCmd, uint64_t a4))
+// clang-format on
+{
+ if (g_pServerLimits->Cvar_sv_antispeedhack_enable->GetBool())
+ {
+ R2::CBaseClient* pClient = &R2::g_pClientArray[player->m_nPlayerIndex - 1];
+
+ if (g_pServerLimits->m_PlayerLimitData.find(pClient) != g_pServerLimits->m_PlayerLimitData.end())
+ {
+ PlayerLimitData* pLimitData = &g_pServerLimits->m_PlayerLimitData[pClient];
+
+ pLimitData->flFrameUserCmdBudget = fmax(0.0, pLimitData->flFrameUserCmdBudget - pUserCmd->frameTime);
+
+ if (pLimitData->flFrameUserCmdBudget <= 0.0)
+ {
+ spdlog::warn("player {} went over usercmd budget ({})", pClient->m_Name, pLimitData->flFrameUserCmdBudget);
+ return;
+ }
+ // else
+ // spdlog::info("{}: {}", pClient->m_Name, pLimitData->flFrameUserCmdBudget);
+ }
+ }
+
+ CPlayerMove__RunCommand(self, player, pUserCmd, a4);
+}
+
+ON_DLL_LOAD_RELIESON("engine.dll", ServerLimits, ConVar, (CModule module))
+{
+ AUTOHOOK_DISPATCH_MODULE(engine.dll)
+
+ g_pServerLimits = new ServerLimitsManager;
+
+ g_pServerLimits->CVar_sv_quota_stringcmdspersecond = new ConVar(
+ "sv_quota_stringcmdspersecond",
+ "60",
+ FCVAR_GAMEDLL,
+ "How many string commands per second clients are allowed to submit, 0 to disallow all string commands, -1 to disable");
+ g_pServerLimits->Cvar_net_chan_limit_mode =
+ new ConVar("net_chan_limit_mode", "0", FCVAR_GAMEDLL, "The mode for netchan processing limits: 0 = warn, 1 = kick");
+ g_pServerLimits->Cvar_net_chan_limit_msec_per_sec = new ConVar(
+ "net_chan_limit_msec_per_sec",
+ "100",
+ FCVAR_GAMEDLL,
+ "Netchannel processing is limited to so many milliseconds, abort connection if exceeding budget");
+ g_pServerLimits->Cvar_sv_querylimit_per_sec = new ConVar("sv_querylimit_per_sec", "15", FCVAR_GAMEDLL, "");
+ g_pServerLimits->Cvar_sv_max_chat_messages_per_sec = new ConVar("sv_max_chat_messages_per_sec", "5", FCVAR_GAMEDLL, "");
+ g_pServerLimits->Cvar_sv_antispeedhack_enable =
+ new ConVar("sv_antispeedhack_enable", "0", FCVAR_NONE, "whether to enable antispeedhack protections");
+ g_pServerLimits->Cvar_sv_antispeedhack_maxtickbudget = new ConVar(
+ "sv_antispeedhack_maxtickbudget",
+ "64",
+ FCVAR_GAMEDLL,
+ "Maximum number of client-issued usercmd ticks that can be replayed in packet loss conditions, 0 to allow no restrictions");
+ g_pServerLimits->Cvar_sv_antispeedhack_budgetincreasemultiplier = new ConVar(
+ "sv_antispeedhack_budgetincreasemultiplier",
+ "1.2",
+ FCVAR_GAMEDLL,
+ "Increase usercmd processing budget by tickinterval * value per tick");
+}
+
+ON_DLL_LOAD("server.dll", ServerLimitsServer, (CModule module))
+{
+ AUTOHOOK_DISPATCH_MODULE(server.dll)
+}