edg-l/ddnet
1
0
Fork 0
mirror of https://github.com/ddnet/ddnet.git synced 2024-11-10 01:58:19 +00:00
Code Issues Packages Projects Releases Wiki Activity

Use a random token for serverbrowse requests

Browse source 
This alleviates the risk for spoofed servers.
This commit is contained in:
heinrich5991 2017-10-14 21:58:23 +02:00
parent 732419de69
commit 16694a0d7b
2 changed files with 70 additions and 35 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

92
src/engine/client/serverbrowser.cpp
View file

@ -5,6 +5,7 @@
#include <base/math.h>
#include <base/system.h>
#include <engine/external/md5/md5.h>
#include <engine/shared/config.h>
#include <engine/shared/memheap.h>
#include <engine/shared/network.h>
@ -56,12 +57,10 @@ CServerBrowser::CServerBrowser()
m_aFilterString[0] = 0;
m_aFilterGametypeString[0] = 0;
// the token is to keep server refresh separated from each other
m_CurrentToken = 1;
m_ServerlistType = 0;
m_BroadcastTime = 0;
m_BroadcastExtraToken = -1;
secure_random_fill(m_aTokenSeed, sizeof(m_aTokenSeed));
m_RequestNumber = 0;
m_pDDNetInfo = 0;
}
@ -91,6 +90,28 @@ const CServerInfo *CServerBrowser::SortedGet(int Index) const
return &m_ppServerlist[m_pSortedServerlist[Index]]->m_Info;
}
int CServerBrowser::GenerateToken(const NETADDR &Addr) const
{
md5_state_t Md5;
md5_byte_t aDigest[16];
md5_init(&Md5);
md5_append(&Md5, m_aTokenSeed, sizeof(m_aTokenSeed));
md5_append(&Md5, (unsigned char *)&Addr, sizeof(Addr));
md5_finish(&Md5, aDigest);
return (aDigest[0] << 16) | (aDigest[1] << 8) | aDigest[2];
}
int CServerBrowser::GetBasicToken(int Token)
{
return Token & 0xff;
}
int CServerBrowser::GetExtraToken(int Token)
{
return Token >> 8;
}
bool CServerBrowser::SortCompareName(int Index1, int Index2) const
{
@ -424,7 +445,6 @@ CServerBrowser::CServerEntry *CServerBrowser::Add(const NETADDR &Addr)
// set the info
pEntry->m_Addr = Addr;
pEntry->m_ExtraToken = secure_rand() & 0xffff;
pEntry->m_Info.m_NetAddr = Addr;
pEntry->m_Info.m_Latency = 999;
@ -499,19 +519,26 @@ void CServerBrowser::Set(const NETADDR &Addr, int Type, int Token, const CServer
}
else if(Type == IServerBrowser::SET_TOKEN)
{
int CheckToken = Token;
int BasicToken = Token;
int ExtraToken = 0;
if(pInfo->m_Type == SERVERINFO_EXTENDED)
{
CheckToken = Token & 0xff;
BasicToken = Token & 0xff;
ExtraToken = Token >> 8;
}
if(CheckToken != m_CurrentToken)
return;
pEntry = Find(Addr);
if(pEntry && pInfo->m_Type == SERVERINFO_EXTENDED)
if(m_ServerlistType != IServerBrowser::TYPE_LAN)
{
if(((Token & 0xffff00) >> 8) != pEntry->m_ExtraToken)
if(!pEntry)
{
return;
}
int Token = GenerateToken(Addr);
bool Drop = false;
Drop = Drop || BasicToken != GetBasicToken(Token);
Drop = Drop || (pInfo->m_Type == SERVERINFO_EXTENDED && ExtraToken != GetExtraToken(Token));
if(Drop)
{
return;
}
@ -520,9 +547,16 @@ void CServerBrowser::Set(const NETADDR &Addr, int Type, int Token, const CServer
pEntry = Add(Addr);
if(pEntry)
{
if(m_ServerlistType == IServerBrowser::TYPE_LAN && pInfo->m_Type == SERVERINFO_EXTENDED)
if(m_ServerlistType == IServerBrowser::TYPE_LAN)
{
if(((Token & 0xffff00) >> 8) != m_BroadcastExtraToken)
NETADDR Broadcast;
mem_zero(&Broadcast, sizeof(Broadcast));
Broadcast.type = m_pNetClient->NetType()|NETTYPE_LINK_BROADCAST;
int Token = GenerateToken(Broadcast);
bool Drop = false;
Drop = Drop || BasicToken != GetBasicToken(Token);
Drop = Drop || (pInfo->m_Type == SERVERINFO_EXTENDED && ExtraToken != GetExtraToken(Token));
if(Drop)
{
return;
}
@ -553,8 +587,7 @@ void CServerBrowser::Refresh(int Type)
m_pLastReqServer = 0;
m_NumRequests = 0;
m_CurrentMaxRequests = g_Config.m_BrMaxRequests;
// next token
m_CurrentToken = (m_CurrentToken+1)&0xff;
m_RequestNumber++;
m_ServerlistType = Type;
@ -564,9 +597,6 @@ void CServerBrowser::Refresh(int Type)
CNetChunk Packet;
int i;
mem_copy(Buffer, SERVERBROWSE_GETINFO, sizeof(SERVERBROWSE_GETINFO));
Buffer[sizeof(SERVERBROWSE_GETINFO)] = m_CurrentToken;
/* do the broadcast version */
Packet.m_ClientID = -1;
mem_zero(&Packet, sizeof(Packet));
@ -575,9 +605,14 @@ void CServerBrowser::Refresh(int Type)
Packet.m_DataSize = sizeof(Buffer);
Packet.m_pData = Buffer;
mem_zero(&Packet.m_aExtraData, sizeof(Packet.m_aExtraData));
m_BroadcastExtraToken = rand() & 0xffff;
Packet.m_aExtraData[0] = m_BroadcastExtraToken >> 8;
Packet.m_aExtraData[1] = m_BroadcastExtraToken & 0xff;
int Token = GenerateToken(Packet.m_Address);
mem_copy(Buffer, SERVERBROWSE_GETINFO, sizeof(SERVERBROWSE_GETINFO));
Buffer[sizeof(SERVERBROWSE_GETINFO)] = GetBasicToken(Token);
Packet.m_aExtraData[0] = GetExtraToken(Token) >> 8;
Packet.m_aExtraData[1] = GetExtraToken(Token) & 0xff;
m_BroadcastTime = time_get();
for(i = 8303; i <= 8310; i++)
@ -633,8 +668,10 @@ void CServerBrowser::RequestImpl(const NETADDR &Addr, CServerEntry *pEntry) cons
m_pConsole->Print(IConsole::OUTPUT_LEVEL_DEBUG, "client_srvbrowse", aBuf);
}
int Token = GenerateToken(Addr);
mem_copy(Buffer, SERVERBROWSE_GETINFO, sizeof(SERVERBROWSE_GETINFO));
Buffer[sizeof(SERVERBROWSE_GETINFO)] = m_CurrentToken;
Buffer[sizeof(SERVERBROWSE_GETINFO)] = GetBasicToken(Token);
Packet.m_ClientID = -1;
Packet.m_Address = Addr;
@ -642,11 +679,8 @@ void CServerBrowser::RequestImpl(const NETADDR &Addr, CServerEntry *pEntry) cons
Packet.m_DataSize = sizeof(Buffer);
Packet.m_pData = Buffer;
mem_zero(&Packet.m_aExtraData, sizeof(Packet.m_aExtraData));
if(pEntry)
{
Packet.m_aExtraData[0] = pEntry->m_ExtraToken >> 8;
Packet.m_aExtraData[1] = pEntry->m_ExtraToken & 0xff;
}
Packet.m_aExtraData[0] = GetExtraToken(Token) >> 8;
Packet.m_aExtraData[1] = GetExtraToken(Token) & 0xff;
m_pNetClient->Send(&Packet);
@ -669,7 +703,7 @@ void CServerBrowser::RequestImpl64(const NETADDR &Addr, CServerEntry *pEntry) co
}
mem_copy(Buffer, SERVERBROWSE_GETINFO_64_LEGACY, sizeof(SERVERBROWSE_GETINFO_64_LEGACY));
Buffer[sizeof(SERVERBROWSE_GETINFO_64_LEGACY)] = m_CurrentToken;
Buffer[sizeof(SERVERBROWSE_GETINFO_64_LEGACY)] = GetBasicToken(GenerateToken(Addr));
Packet.m_ClientID = -1;
Packet.m_Address = Addr;

13
src/engine/client/serverbrowser.h
View file

@ -17,7 +17,6 @@ public:
int64 m_RequestTime;
int m_GotInfo;
bool m_Request64Legacy;
int m_ExtraToken;
CServerInfo m_Info;
CServerEntry *m_pNextIp; // ip hashed list
@ -151,14 +150,16 @@ private:
char m_aFilterString[64];
char m_aFilterGametypeString[128];
// the token is to keep server refresh separated from each other
int m_CurrentToken;
int m_ServerlistType;
int64 m_BroadcastTime;
int m_BroadcastExtraToken;
int m_RequestNumber;
unsigned char m_aTokenSeed[16];
// sorting criterions
int GenerateToken(const NETADDR &Addr) const;
static int GetBasicToken(int Token);
static int GetExtraToken(int Token);
// sorting criteria
bool SortCompareName(int Index1, int Index2) const;
bool SortCompareMap(int Index1, int Index2) const;
bool SortComparePing(int Index1, int Index2) const;