ddnet/src/engine/shared/network_server.cpp
heinrich5991 17402cc43f Rename all variables for strict camel-casing of abbreviations
This is the strict version, ID → Id, UI → Ui, except DDNet which stays
DDNet.

This would fix #7750.

Done using a naive rename script (for bash, use `shopt -s globstar`):

```fish
sed -i \
	-e 's/\([a-z]_\?\)ID/\1Id/g' \
	-e 's/\([^ ]\)\<UI\>/\1Ui/g' \
	-e 's/UI()/Ui()/g' \
	-e 's/\<CUI\>/CUi/g' \
	-e 's/\([\ta-z.(&]\|[,=|] \)ID\>/\1Id/g' \
	-e 's/\<ID\>\([^ ").]\)/Id\1/g' \
	-e 's/\<ID\([0-9]\)/Id\1/g' \
	-e 's/\<ID\>\( [<=>:+*/-]\)/Id\1/g' \
	-e 's/int ID/int Id/g' \
	-e 's/\([a-z]_\?\)GPU/\1Gpu/g' \
	-e 's/\([a-z]_\?\)IP/\1Ip/g' \
	-e 's/\([a-z]_\?\)CID/\1Cid/g' \
	-e 's/\([a-z]_\?\)MySQL/\1Mysql/g' \
	-e 's/MySql/Mysql/g' \
	-e 's/\([a-xz]_\?\)SQL/\1Sql/g' \
	-e 's/DPMode/DpMode/g' \
	-e 's/TTWGraphics/TTwGraphics/g' \
	\
	-e 's/Ipointer/IPointer/g' \
	-e 's/\.vendorId/.vendorID/g' \
	-e 's/\.windowId/.windowID/g' \
	-e 's/SDL_GetWindowFromId/SDL_GetWindowFromID/g' \
	-e 's/SDL_AudioDeviceId/SDL_AudioDeviceID/g' \
	-e 's/SDL_JoystickId/SDL_JoystickID/g' \
	-e 's/SDL_JoystickInstanceId/SDL_JoystickInstanceID/g' \
	-e 's/AVCodecId/AVCodecID/g' \
	src/**/*.cpp src/**/*.h {datasrc,scripts}/**/*.py
git checkout -- src/engine/external
```

I like this option because it presents clear rules.

Still needs fixups because of the naive replacement, I'd do this if we
want this merged.
2024-03-05 15:44:09 +01:00

823 lines
23 KiB
C++

/* (c) Magnus Auvinen. See licence.txt in the root of the distribution for more information. */
/* If you are missing that file, acquire a complete release at teeworlds.com. */
#include <base/hash_ctxt.h>
#include <base/system.h>
#include "config.h"
#include "netban.h"
#include "network.h"
#include <engine/shared/compression.h>
#include <engine/shared/packer.h>
#include <engine/shared/protocol.h>
const int g_DummyMapCrc = 0xD6909B17;
const unsigned char g_aDummyMapData[] = {
0x44, 0x41, 0x54, 0x41, 0x04, 0x00, 0x00, 0x00, 0xFA, 0x00, 0x00, 0x00,
0xEC, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00,
0x01, 0x00, 0x00, 0x00, 0xAC, 0x00, 0x00, 0x00, 0x0E, 0x00, 0x00, 0x00,
0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
0x05, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x68, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00,
0x1C, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0x00,
0x3C, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF,
0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x05, 0x00, 0x3C, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF,
0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00,
0x78, 0x9C, 0x63, 0x64, 0x60, 0x60, 0x60, 0x44, 0xC2, 0x00, 0x00, 0x38,
0x00, 0x05};
static SECURITY_TOKEN ToSecurityToken(const unsigned char *pData)
{
return (int)pData[0] | (pData[1] << 8) | (pData[2] << 16) | (pData[3] << 24);
}
bool CNetServer::Open(NETADDR BindAddr, CNetBan *pNetBan, int MaxClients, int MaxClientsPerIp)
{
// zero out the whole structure
this->~CNetServer();
new(this) CNetServer{};
// open socket
m_Socket = net_udp_create(BindAddr);
if(!m_Socket)
return false;
m_Address = BindAddr;
m_pNetBan = pNetBan;
m_MaxClients = clamp(MaxClients, 1, (int)NET_MAX_CLIENTS);
m_MaxClientsPerIp = MaxClientsPerIp;
m_NumConAttempts = 0;
m_TimeNumConAttempts = time_get();
m_VConnNum = 0;
m_VConnFirst = 0;
secure_random_fill(m_aSecurityTokenSeed, sizeof(m_aSecurityTokenSeed));
for(auto &Slot : m_aSlots)
Slot.m_Connection.Init(m_Socket, true);
return true;
}
int CNetServer::SetCallbacks(NETFUNC_NEWCLIENT pfnNewClient, NETFUNC_DELCLIENT pfnDelClient, void *pUser)
{
m_pfnNewClient = pfnNewClient;
m_pfnDelClient = pfnDelClient;
m_pUser = pUser;
return 0;
}
int CNetServer::SetCallbacks(NETFUNC_NEWCLIENT pfnNewClient, NETFUNC_NEWCLIENT_NOAUTH pfnNewClientNoAuth, NETFUNC_CLIENTREJOIN pfnClientRejoin, NETFUNC_DELCLIENT pfnDelClient, void *pUser)
{
m_pfnNewClient = pfnNewClient;
m_pfnNewClientNoAuth = pfnNewClientNoAuth;
m_pfnClientRejoin = pfnClientRejoin;
m_pfnDelClient = pfnDelClient;
m_pUser = pUser;
return 0;
}
int CNetServer::Close()
{
if(!m_Socket)
return 0;
return net_udp_close(m_Socket);
}
int CNetServer::Drop(int ClientId, const char *pReason)
{
// TODO: insert lots of checks here
if(m_pfnDelClient)
m_pfnDelClient(ClientId, pReason, m_pUser);
m_aSlots[ClientId].m_Connection.Disconnect(pReason);
return 0;
}
int CNetServer::Update()
{
for(int i = 0; i < MaxClients(); i++)
{
m_aSlots[i].m_Connection.Update();
if(m_aSlots[i].m_Connection.State() == NET_CONNSTATE_ERROR &&
(!m_aSlots[i].m_Connection.m_TimeoutProtected ||
!m_aSlots[i].m_Connection.m_TimeoutSituation))
{
Drop(i, m_aSlots[i].m_Connection.ErrorString());
}
}
return 0;
}
SECURITY_TOKEN CNetServer::GetGlobalToken()
{
static NETADDR NullAddr = {0};
return GetToken(NullAddr);
}
SECURITY_TOKEN CNetServer::GetToken(const NETADDR &Addr)
{
SHA256_CTX Sha256;
sha256_init(&Sha256);
sha256_update(&Sha256, (unsigned char *)m_aSecurityTokenSeed, sizeof(m_aSecurityTokenSeed));
sha256_update(&Sha256, (unsigned char *)&Addr, 20); // omit port, bad idea!
SECURITY_TOKEN SecurityToken = ToSecurityToken(sha256_finish(&Sha256).data);
if(SecurityToken == NET_SECURITY_TOKEN_UNKNOWN ||
SecurityToken == NET_SECURITY_TOKEN_UNSUPPORTED)
SecurityToken = 1;
return SecurityToken;
}
void CNetServer::SendControl(NETADDR &Addr, int ControlMsg, const void *pExtra, int ExtraSize, SECURITY_TOKEN SecurityToken)
{
CNetBase::SendControlMsg(m_Socket, &Addr, 0, ControlMsg, pExtra, ExtraSize, SecurityToken);
}
int CNetServer::NumClientsWithAddr(NETADDR Addr)
{
int FoundAddr = 0;
for(int i = 0; i < MaxClients(); ++i)
{
if(m_aSlots[i].m_Connection.State() == NET_CONNSTATE_OFFLINE ||
(m_aSlots[i].m_Connection.State() == NET_CONNSTATE_ERROR &&
(!m_aSlots[i].m_Connection.m_TimeoutProtected ||
!m_aSlots[i].m_Connection.m_TimeoutSituation)))
continue;
if(!net_addr_comp_noport(&Addr, m_aSlots[i].m_Connection.PeerAddress()))
FoundAddr++;
}
return FoundAddr;
}
bool CNetServer::Connlimit(NETADDR Addr)
{
int64_t Now = time_get();
int Oldest = 0;
for(int i = 0; i < NET_CONNLIMIT_IPS; ++i)
{
if(!net_addr_comp(&m_aSpamConns[i].m_Addr, &Addr))
{
if(m_aSpamConns[i].m_Time > Now - time_freq() * g_Config.m_SvConnlimitTime)
{
if(m_aSpamConns[i].m_Conns >= g_Config.m_SvConnlimit)
return true;
}
else
{
m_aSpamConns[i].m_Time = Now;
m_aSpamConns[i].m_Conns = 0;
}
m_aSpamConns[i].m_Conns++;
return false;
}
if(m_aSpamConns[i].m_Time < m_aSpamConns[Oldest].m_Time)
Oldest = i;
}
m_aSpamConns[Oldest].m_Addr = Addr;
m_aSpamConns[Oldest].m_Time = Now;
m_aSpamConns[Oldest].m_Conns = 1;
return false;
}
int CNetServer::TryAcceptClient(NETADDR &Addr, SECURITY_TOKEN SecurityToken, bool VanillaAuth, bool Sixup, SECURITY_TOKEN Token)
{
if(Sixup && !g_Config.m_SvSixup)
{
const char aMsg[] = "0.7 connections are not accepted at this time";
CNetBase::SendControlMsg(m_Socket, &Addr, 0, NET_CTRLMSG_CLOSE, aMsg, sizeof(aMsg), SecurityToken, Sixup);
return -1; // failed to add client?
}
if(Connlimit(Addr))
{
const char aMsg[] = "Too many connections in a short time";
CNetBase::SendControlMsg(m_Socket, &Addr, 0, NET_CTRLMSG_CLOSE, aMsg, sizeof(aMsg), SecurityToken, Sixup);
return -1; // failed to add client
}
// check for sv_max_clients_per_ip
if(NumClientsWithAddr(Addr) + 1 > m_MaxClientsPerIp)
{
char aBuf[128];
str_format(aBuf, sizeof(aBuf), "Only %d players with the same IP are allowed", m_MaxClientsPerIp);
CNetBase::SendControlMsg(m_Socket, &Addr, 0, NET_CTRLMSG_CLOSE, aBuf, str_length(aBuf) + 1, SecurityToken, Sixup);
return -1; // failed to add client
}
int Slot = -1;
for(int i = 0; i < MaxClients(); i++)
{
if(m_aSlots[i].m_Connection.State() == NET_CONNSTATE_OFFLINE)
{
Slot = i;
break;
}
}
if(Slot == -1)
{
const char aFullMsg[] = "This server is full";
CNetBase::SendControlMsg(m_Socket, &Addr, 0, NET_CTRLMSG_CLOSE, aFullMsg, sizeof(aFullMsg), SecurityToken, Sixup);
return -1; // failed to add client
}
// init connection slot
m_aSlots[Slot].m_Connection.DirectInit(Addr, SecurityToken, Token, Sixup);
if(VanillaAuth)
{
// client sequence is unknown if the auth was done
// connection-less
m_aSlots[Slot].m_Connection.SetUnknownSeq();
// correct sequence
m_aSlots[Slot].m_Connection.SetSequence(6);
}
if(g_Config.m_Debug)
{
char aAddrStr[NETADDR_MAXSTRSIZE];
net_addr_str(&Addr, aAddrStr, sizeof(aAddrStr), true);
dbg_msg("security", "client accepted %s", aAddrStr);
}
if(VanillaAuth)
m_pfnNewClientNoAuth(Slot, m_pUser);
else
m_pfnNewClient(Slot, m_pUser, Sixup);
return Slot; // done
}
void CNetServer::SendMsgs(NETADDR &Addr, const CPacker **ppMsgs, int Num)
{
CNetPacketConstruct Construct;
mem_zero(&Construct, sizeof(Construct));
unsigned char *pChunkData = &Construct.m_aChunkData[Construct.m_DataSize];
for(int i = 0; i < Num; i++)
{
const CPacker *pMsg = ppMsgs[i];
CNetChunkHeader Header;
Header.m_Flags = NET_CHUNKFLAG_VITAL;
Header.m_Size = pMsg->Size();
Header.m_Sequence = i + 1;
pChunkData = Header.Pack(pChunkData);
mem_copy(pChunkData, pMsg->Data(), pMsg->Size());
pChunkData += pMsg->Size();
Construct.m_NumChunks++;
}
Construct.m_DataSize = (int)(pChunkData - Construct.m_aChunkData);
CNetBase::SendPacket(m_Socket, &Addr, &Construct, NET_SECURITY_TOKEN_UNSUPPORTED);
}
// connection-less msg packet without token-support
void CNetServer::OnPreConnMsg(NETADDR &Addr, CNetPacketConstruct &Packet)
{
bool IsCtrl = Packet.m_Flags & NET_PACKETFLAG_CONTROL;
int CtrlMsg = m_RecvUnpacker.m_Data.m_aChunkData[0];
// log flooding
//TODO: remove
if(g_Config.m_Debug)
{
int64_t Now = time_get();
if(Now - m_TimeNumConAttempts > time_freq())
// reset
m_NumConAttempts = 0;
m_NumConAttempts++;
if(m_NumConAttempts > 100)
{
dbg_msg("security", "flooding detected");
m_TimeNumConAttempts = Now;
m_NumConAttempts = 0;
}
}
if(IsCtrl && CtrlMsg == NET_CTRLMSG_CONNECT)
{
if(g_Config.m_SvVanillaAntiSpoof && g_Config.m_Password[0] == '\0')
{
bool Flooding = false;
if(g_Config.m_SvVanConnPerSecond)
{
// detect flooding
Flooding = m_VConnNum > g_Config.m_SvVanConnPerSecond;
const int64_t Now = time_get();
if(Now <= m_VConnFirst + time_freq())
{
m_VConnNum++;
}
else
{
m_VConnNum = 1;
m_VConnFirst = Now;
}
}
if(g_Config.m_Debug && Flooding)
{
dbg_msg("security", "vanilla connection flooding detected");
}
// simulate accept
SendControl(Addr, NET_CTRLMSG_CONNECTACCEPT, NULL, 0, NET_SECURITY_TOKEN_UNSUPPORTED);
// Begin vanilla compatible token handshake
// The idea is to pack a security token in the gametick
// parameter of NETMSG_SNAPEMPTY. The Client then will
// return the token/gametick in NETMSG_INPUT, allowing
// us to validate the token.
// https://github.com/eeeee/ddnet/commit/b8e40a244af4e242dc568aa34854c5754c75a39a
// Before we can send NETMSG_SNAPEMPTY, the client needs
// to load a map, otherwise it might crash. The map
// should be as small as is possible and directly available
// to the client. Therefore a dummy map is sent in the same
// packet. To reduce the traffic we'll fallback to a default
// map if there are too many connection attempts at once.
// send mapchange + map data + con_ready + 3 x empty snap (with token)
CPacker MapChangeMsg;
MapChangeMsg.Reset();
MapChangeMsg.AddInt((NETMSG_MAP_CHANGE << 1) | 1);
if(Flooding)
{
// Fallback to dm1
MapChangeMsg.AddString("dm1", 0);
MapChangeMsg.AddInt(0xf2159e6e);
MapChangeMsg.AddInt(5805);
}
else
{
// dummy map
MapChangeMsg.AddString("dummy", 0);
MapChangeMsg.AddInt(g_DummyMapCrc);
MapChangeMsg.AddInt(sizeof(g_aDummyMapData));
}
CPacker MapDataMsg;
MapDataMsg.Reset();
MapDataMsg.AddInt((NETMSG_MAP_DATA << 1) | 1);
if(Flooding)
{
// send empty map data to keep 0.6.4 support
MapDataMsg.AddInt(1); // last chunk
MapDataMsg.AddInt(0); // crc
MapDataMsg.AddInt(0); // chunk index
MapDataMsg.AddInt(0); // map size
MapDataMsg.AddRaw(NULL, 0); // map data
}
else
{
// send dummy map data
MapDataMsg.AddInt(1); // last chunk
MapDataMsg.AddInt(g_DummyMapCrc); // crc
MapDataMsg.AddInt(0); // chunk index
MapDataMsg.AddInt(sizeof(g_aDummyMapData)); // map size
MapDataMsg.AddRaw(g_aDummyMapData, sizeof(g_aDummyMapData)); // map data
}
CPacker ConReadyMsg;
ConReadyMsg.Reset();
ConReadyMsg.AddInt((NETMSG_CON_READY << 1) | 1);
CPacker SnapEmptyMsg;
SnapEmptyMsg.Reset();
SnapEmptyMsg.AddInt((NETMSG_SNAPEMPTY << 1) | 1);
SECURITY_TOKEN SecurityToken = GetVanillaToken(Addr);
SnapEmptyMsg.AddInt(SecurityToken);
SnapEmptyMsg.AddInt(SecurityToken + 1);
// send all chunks/msgs in one packet
const CPacker *apMsgs[] = {&MapChangeMsg, &MapDataMsg, &ConReadyMsg,
&SnapEmptyMsg, &SnapEmptyMsg, &SnapEmptyMsg};
SendMsgs(Addr, apMsgs, std::size(apMsgs));
}
else
{
// accept client directly
SendControl(Addr, NET_CTRLMSG_CONNECTACCEPT, NULL, 0, NET_SECURITY_TOKEN_UNSUPPORTED);
TryAcceptClient(Addr, NET_SECURITY_TOKEN_UNSUPPORTED);
}
}
else if(!IsCtrl && g_Config.m_SvVanillaAntiSpoof && g_Config.m_Password[0] == '\0')
{
CNetChunkHeader h;
unsigned char *pData = Packet.m_aChunkData;
pData = h.Unpack(pData);
CUnpacker Unpacker;
Unpacker.Reset(pData, h.m_Size);
int Msg = Unpacker.GetInt() >> 1;
if(Msg == NETMSG_INPUT)
{
SECURITY_TOKEN SecurityToken = Unpacker.GetInt();
if(SecurityToken == GetVanillaToken(Addr))
{
if(g_Config.m_Debug)
dbg_msg("security", "new client (vanilla handshake)");
// try to accept client skipping auth state
TryAcceptClient(Addr, NET_SECURITY_TOKEN_UNSUPPORTED, true);
}
else if(g_Config.m_Debug)
dbg_msg("security", "invalid token (vanilla handshake)");
}
else
{
if(g_Config.m_Debug)
{
dbg_msg("security", "invalid preconn msg %d", Msg);
}
}
}
}
void CNetServer::OnConnCtrlMsg(NETADDR &Addr, int ClientId, int ControlMsg, const CNetPacketConstruct &Packet)
{
if(ControlMsg == NET_CTRLMSG_CONNECT)
{
// got connection attempt inside of valid session
// the client probably wants to reconnect
bool SupportsToken = Packet.m_DataSize >=
(int)(1 + sizeof(SECURITY_TOKEN_MAGIC) + sizeof(SECURITY_TOKEN)) &&
!mem_comp(&Packet.m_aChunkData[1], SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC));
if(SupportsToken)
{
// response connection request with token
SECURITY_TOKEN Token = GetToken(Addr);
SendControl(Addr, NET_CTRLMSG_CONNECTACCEPT, SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC), Token);
}
if(g_Config.m_Debug)
dbg_msg("security", "client %d wants to reconnect", ClientId);
}
else if(ControlMsg == NET_CTRLMSG_ACCEPT && Packet.m_DataSize == 1 + sizeof(SECURITY_TOKEN))
{
SECURITY_TOKEN Token = ToSecurityToken(&Packet.m_aChunkData[1]);
if(Token == GetToken(Addr))
{
// correct token
// try to accept client
if(g_Config.m_Debug)
dbg_msg("security", "client %d reconnect", ClientId);
// reset netconn and process rejoin
m_aSlots[ClientId].m_Connection.Reset(true);
m_pfnClientRejoin(ClientId, m_pUser);
}
}
}
void CNetServer::OnTokenCtrlMsg(NETADDR &Addr, int ControlMsg, const CNetPacketConstruct &Packet)
{
if(ClientExists(Addr))
return; // silently ignore
if(Addr.type == NETTYPE_WEBSOCKET_IPV4)
{
// websocket client doesn't send token
// direct accept
SendControl(Addr, NET_CTRLMSG_CONNECTACCEPT, SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC), NET_SECURITY_TOKEN_UNSUPPORTED);
TryAcceptClient(Addr, NET_SECURITY_TOKEN_UNSUPPORTED);
}
else if(ControlMsg == NET_CTRLMSG_CONNECT)
{
// response connection request with token
SECURITY_TOKEN Token = GetToken(Addr);
SendControl(Addr, NET_CTRLMSG_CONNECTACCEPT, SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC), Token);
}
else if(ControlMsg == NET_CTRLMSG_ACCEPT)
{
SECURITY_TOKEN Token = ToSecurityToken(&Packet.m_aChunkData[1]);
if(Token == GetToken(Addr))
{
// correct token
// try to accept client
if(g_Config.m_Debug)
dbg_msg("security", "new client (ddnet token)");
TryAcceptClient(Addr, Token);
}
else
{
// invalid token
if(g_Config.m_Debug)
dbg_msg("security", "invalid token");
}
}
}
int CNetServer::OnSixupCtrlMsg(NETADDR &Addr, CNetChunk *pChunk, int ControlMsg, const CNetPacketConstruct &Packet, SECURITY_TOKEN &ResponseToken, SECURITY_TOKEN Token)
{
if(m_RecvUnpacker.m_Data.m_DataSize < 5 || ClientExists(Addr))
return 0; // silently ignore
mem_copy(&ResponseToken, Packet.m_aChunkData + 1, 4);
if(ControlMsg == 5)
{
if(m_RecvUnpacker.m_Data.m_DataSize >= 512)
{
SendTokenSixup(Addr, ResponseToken);
return 0;
}
// Is this behaviour safe to rely on?
pChunk->m_Flags = 0;
pChunk->m_ClientId = -1;
pChunk->m_Address = Addr;
pChunk->m_DataSize = 0;
return 1;
}
else if(ControlMsg == NET_CTRLMSG_CONNECT)
{
SECURITY_TOKEN MyToken = GetToken(Addr);
unsigned char aToken[sizeof(SECURITY_TOKEN)];
mem_copy(aToken, &MyToken, sizeof(aToken));
CNetBase::SendControlMsg(m_Socket, &Addr, 0, NET_CTRLMSG_CONNECTACCEPT, aToken, sizeof(aToken), ResponseToken, true);
if(Token == MyToken)
TryAcceptClient(Addr, ResponseToken, false, true, Token);
}
return 0;
}
int CNetServer::GetClientSlot(const NETADDR &Addr)
{
int Slot = -1;
for(int i = 0; i < MaxClients(); i++)
{
if(m_aSlots[i].m_Connection.State() != NET_CONNSTATE_OFFLINE &&
m_aSlots[i].m_Connection.State() != NET_CONNSTATE_ERROR &&
net_addr_comp(m_aSlots[i].m_Connection.PeerAddress(), &Addr) == 0)
{
Slot = i;
}
}
return Slot;
}
static bool IsDDNetControlMsg(const CNetPacketConstruct *pPacket)
{
if(!(pPacket->m_Flags & NET_PACKETFLAG_CONTROL) || pPacket->m_DataSize < 1)
{
return false;
}
if(pPacket->m_aChunkData[0] == NET_CTRLMSG_CONNECT && pPacket->m_DataSize >= (int)(1 + sizeof(SECURITY_TOKEN_MAGIC) + sizeof(SECURITY_TOKEN)) && mem_comp(&pPacket->m_aChunkData[1], SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC)) == 0)
{
// DDNet CONNECT
return true;
}
if(pPacket->m_aChunkData[0] == NET_CTRLMSG_ACCEPT && pPacket->m_DataSize >= 1 + (int)sizeof(SECURITY_TOKEN))
{
// DDNet ACCEPT
return true;
}
return false;
}
/*
TODO: chopp up this function into smaller working parts
*/
int CNetServer::Recv(CNetChunk *pChunk, SECURITY_TOKEN *pResponseToken)
{
while(true)
{
NETADDR Addr;
// check for a chunk
if(m_RecvUnpacker.FetchChunk(pChunk))
return 1;
// TODO: empty the recvinfo
unsigned char *pData;
int Bytes = net_udp_recv(m_Socket, &Addr, &pData);
// no more packets for now
if(Bytes <= 0)
break;
// check if we just should drop the packet
char aBuf[128];
if(NetBan() && NetBan()->IsBanned(&Addr, aBuf, sizeof(aBuf)))
{
// banned, reply with a message
CNetBase::SendControlMsg(m_Socket, &Addr, 0, NET_CTRLMSG_CLOSE, aBuf, str_length(aBuf) + 1, NET_SECURITY_TOKEN_UNSUPPORTED);
continue;
}
SECURITY_TOKEN Token;
bool Sixup = false;
*pResponseToken = NET_SECURITY_TOKEN_UNKNOWN;
if(CNetBase::UnpackPacket(pData, Bytes, &m_RecvUnpacker.m_Data, Sixup, &Token, pResponseToken) == 0)
{
if(m_RecvUnpacker.m_Data.m_Flags & NET_PACKETFLAG_CONNLESS)
{
if(Sixup && Token != GetToken(Addr) && Token != GetGlobalToken())
continue;
pChunk->m_Flags = NETSENDFLAG_CONNLESS;
pChunk->m_ClientId = -1;
pChunk->m_Address = Addr;
pChunk->m_DataSize = m_RecvUnpacker.m_Data.m_DataSize;
pChunk->m_pData = m_RecvUnpacker.m_Data.m_aChunkData;
if(m_RecvUnpacker.m_Data.m_Flags & NET_PACKETFLAG_EXTENDED)
{
pChunk->m_Flags |= NETSENDFLAG_EXTENDED;
mem_copy(pChunk->m_aExtraData, m_RecvUnpacker.m_Data.m_aExtraData, sizeof(pChunk->m_aExtraData));
}
return 1;
}
else
{
// drop invalid ctrl packets
if(m_RecvUnpacker.m_Data.m_Flags & NET_PACKETFLAG_CONTROL &&
m_RecvUnpacker.m_Data.m_DataSize == 0)
continue;
// normal packet, find matching slot
int Slot = GetClientSlot(Addr);
if(!Sixup && Slot != -1 && m_aSlots[Slot].m_Connection.m_Sixup)
{
Sixup = true;
if(CNetBase::UnpackPacket(pData, Bytes, &m_RecvUnpacker.m_Data, Sixup, &Token))
continue;
}
if(Slot != -1)
{
// found
// control
if(m_RecvUnpacker.m_Data.m_Flags & NET_PACKETFLAG_CONTROL)
OnConnCtrlMsg(Addr, Slot, m_RecvUnpacker.m_Data.m_aChunkData[0], m_RecvUnpacker.m_Data);
if(m_aSlots[Slot].m_Connection.Feed(&m_RecvUnpacker.m_Data, &Addr, Token))
{
if(m_RecvUnpacker.m_Data.m_DataSize)
m_RecvUnpacker.Start(&Addr, &m_aSlots[Slot].m_Connection, Slot);
}
}
else
{
// not found, client that wants to connect
if(Sixup)
{
// got 0.7 control msg
if(OnSixupCtrlMsg(Addr, pChunk, m_RecvUnpacker.m_Data.m_aChunkData[0], m_RecvUnpacker.m_Data, *pResponseToken, Token) == 1)
return 1;
}
else if(IsDDNetControlMsg(&m_RecvUnpacker.m_Data))
{
// got ddnet control msg
OnTokenCtrlMsg(Addr, m_RecvUnpacker.m_Data.m_aChunkData[0], m_RecvUnpacker.m_Data);
}
else
{
// got connection-less ctrl or sys msg
OnPreConnMsg(Addr, m_RecvUnpacker.m_Data);
}
}
}
}
}
return 0;
}
int CNetServer::Send(CNetChunk *pChunk)
{
if(pChunk->m_DataSize >= NET_MAX_PAYLOAD)
{
dbg_msg("netserver", "packet payload too big. %d. dropping packet", pChunk->m_DataSize);
return -1;
}
if(pChunk->m_Flags & NETSENDFLAG_CONNLESS)
{
// send connectionless packet
CNetBase::SendPacketConnless(m_Socket, &pChunk->m_Address, pChunk->m_pData, pChunk->m_DataSize,
pChunk->m_Flags & NETSENDFLAG_EXTENDED, pChunk->m_aExtraData);
}
else
{
int Flags = 0;
dbg_assert(pChunk->m_ClientId >= 0, "erroneous client id");
dbg_assert(pChunk->m_ClientId < MaxClients(), "erroneous client id");
if(pChunk->m_Flags & NETSENDFLAG_VITAL)
Flags = NET_CHUNKFLAG_VITAL;
if(m_aSlots[pChunk->m_ClientId].m_Connection.QueueChunk(Flags, pChunk->m_DataSize, pChunk->m_pData) == 0)
{
if(pChunk->m_Flags & NETSENDFLAG_FLUSH)
m_aSlots[pChunk->m_ClientId].m_Connection.Flush();
}
else
{
//Drop(pChunk->m_ClientId, "Error sending data");
}
}
return 0;
}
void CNetServer::SendTokenSixup(NETADDR &Addr, SECURITY_TOKEN Token)
{
SECURITY_TOKEN MyToken = GetToken(Addr);
unsigned char aBuf[512] = {};
mem_copy(aBuf, &MyToken, 4);
int Size = (Token == NET_SECURITY_TOKEN_UNKNOWN) ? 512 : 4;
CNetBase::SendControlMsg(m_Socket, &Addr, 0, 5, aBuf, Size, Token, true);
}
int CNetServer::SendConnlessSixup(CNetChunk *pChunk, SECURITY_TOKEN ResponseToken)
{
if(pChunk->m_DataSize > NET_MAX_PACKETSIZE - 9)
return -1;
unsigned char aBuffer[NET_MAX_PACKETSIZE];
aBuffer[0] = NET_PACKETFLAG_CONNLESS << 2 | 1;
SECURITY_TOKEN Token = GetToken(pChunk->m_Address);
mem_copy(aBuffer + 1, &ResponseToken, 4);
mem_copy(aBuffer + 5, &Token, 4);
mem_copy(aBuffer + 9, pChunk->m_pData, pChunk->m_DataSize);
net_udp_send(m_Socket, &pChunk->m_Address, aBuffer, pChunk->m_DataSize + 9);
return 0;
}
void CNetServer::SetMaxClientsPerIp(int Max)
{
// clamp
if(Max < 1)
Max = 1;
else if(Max > NET_MAX_CLIENTS)
Max = NET_MAX_CLIENTS;
m_MaxClientsPerIp = Max;
}
bool CNetServer::SetTimedOut(int ClientId, int OrigId)
{
if(m_aSlots[ClientId].m_Connection.State() != NET_CONNSTATE_ERROR)
return false;
m_aSlots[ClientId].m_Connection.SetTimedOut(ClientAddr(OrigId), m_aSlots[OrigId].m_Connection.SeqSequence(), m_aSlots[OrigId].m_Connection.AckSequence(), m_aSlots[OrigId].m_Connection.SecurityToken(), m_aSlots[OrigId].m_Connection.ResendBuffer(), m_aSlots[OrigId].m_Connection.m_Sixup);
m_aSlots[OrigId].m_Connection.Reset();
return true;
}
void CNetServer::SetTimeoutProtected(int ClientId)
{
m_aSlots[ClientId].m_Connection.m_TimeoutProtected = true;
}
int CNetServer::ResetErrorString(int ClientId)
{
m_aSlots[ClientId].m_Connection.ResetErrorString();
return 0;
}
const char *CNetServer::ErrorString(int ClientId)
{
return m_aSlots[ClientId].m_Connection.ErrorString();
}