also block floods of getstatus, getinfo, getchallenge

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@11757 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/netconn.c b/netconn.c
index 28e4ef68e571e9a9d56df7b23c1e132b7c7ef0ac..2147926fb6f5ee7644524b10f0c74e75ad11dfd2 100755 (executable)
--- a/netconn.c
+++ b/netconn.c
@@ -78,7 +78,9 @@ char sv_readstring[MAX_INPUTLINE];
 
 cvar_t net_messagetimeout = {0, "net_messagetimeout","300", "drops players who have not sent any packets for this many seconds"};
 cvar_t net_connecttimeout = {0, "net_connecttimeout","15", "after requesting a connection, the client must reply within this many seconds or be dropped (cuts down on connect floods). Must be above 10 seconds."};
-cvar_t net_connectfloodblockingtimeout = {0, "net_connectfloodblockingtimeout", "5", "when a connection packet is received, it will block all future connect packets from that IP address for this many seconds (cuts down on connect floods)"};
+cvar_t net_connectfloodblockingtimeout = {0, "net_connectfloodblockingtimeout", "5", "when a connection packet is received, it will block all future connect packets from that IP address for this many seconds (cuts down on connect floods). Note that this does not include retries from the same IP; these are handled earlier and let in."};
+cvar_t net_challengefloodblockingtimeout = {0, "net_challengefloodblockingtimeout", "0.5", "when a challenge packet is received, it will block all future challenge packets from that IP address for this many seconds (cuts down on challenge floods). DarkPlaces clients retry once per second, so this should be <= 1. Failure here may lead to connect attempts failing."};
+cvar_t net_getstatusfloodblockingtimeout = {0, "net_getstatusfloodblockingtimeout", "1", "when a getstatus packet is received, it will block all future getstatus packets from that IP address for this many seconds (cuts down on getstatus floods). DarkPlaces retries every 4 seconds, and qstat retries once per second, so this should be <= 1. Failure here may lead to server not showing up in the server list."};
 cvar_t hostname = {CVAR_SAVE, "hostname", "UNNAMED", "server message to show in server browser"};
 cvar_t developer_networking = {0, "developer_networking", "0", "prints all received and sent packets (recommended only for debugging)"};
 
@@ -1056,14 +1058,14 @@ netconn_t *NetConn_Open(lhnetsocket_t *mysocket, lhnetaddress_t *peeraddress)
        return conn;
 }
 
-void NetConn_ClearConnectFlood(lhnetaddress_t *peeraddress);
+void NetConn_ClearFlood(lhnetaddress_t *peeraddress, server_floodaddress_t *floodlist, size_t floodlength);
 void NetConn_Close(netconn_t *conn)
 {
        netconn_t *c;
        // remove connection from list
 
        // allow the client to reconnect immediately
-       NetConn_ClearConnectFlood(&(conn->peeraddress));
+       NetConn_ClearFlood(&(conn->peeraddress), sv.connectfloodaddresses, sizeof(sv.connectfloodaddresses) / sizeof(sv.connectfloodaddresses[0]));
 
        if (conn == netconn_list)
                netconn_list = conn->next;
@@ -2496,31 +2498,34 @@ bad:
        return false;
 }
 
-static qboolean NetConn_PreventConnectFlood(lhnetaddress_t *peeraddress)
+static qboolean NetConn_PreventFlood(lhnetaddress_t *peeraddress, server_floodaddress_t *floodlist, size_t floodlength, double floodtime, qboolean renew)
 {
-       int floodslotnum, bestfloodslotnum;
+       size_t floodslotnum, bestfloodslotnum;
        double bestfloodtime;
        lhnetaddress_t noportpeeraddress;
        // see if this is a connect flood
        noportpeeraddress = *peeraddress;
        LHNETADDRESS_SetPort(&noportpeeraddress, 0);
        bestfloodslotnum = 0;
-       bestfloodtime = sv.connectfloodaddresses[bestfloodslotnum].lasttime;
-       for (floodslotnum = 0;floodslotnum < MAX_CONNECTFLOODADDRESSES;floodslotnum++)
+       bestfloodtime = floodlist[bestfloodslotnum].lasttime;
+       for (floodslotnum = 0;floodslotnum < floodlength;floodslotnum++)
        {
-               if (bestfloodtime >= sv.connectfloodaddresses[floodslotnum].lasttime)
+               if (bestfloodtime >= floodlist[floodslotnum].lasttime)
                {
-                       bestfloodtime = sv.connectfloodaddresses[floodslotnum].lasttime;
+                       bestfloodtime = floodlist[floodslotnum].lasttime;
                        bestfloodslotnum = floodslotnum;
                }
-               if (sv.connectfloodaddresses[floodslotnum].lasttime && LHNETADDRESS_Compare(&noportpeeraddress, &sv.connectfloodaddresses[floodslotnum].address) == 0)
+               if (floodlist[floodslotnum].lasttime && LHNETADDRESS_Compare(&noportpeeraddress, &floodlist[floodslotnum].address) == 0)
                {
                        // this address matches an ongoing flood address
-                       if (realtime < sv.connectfloodaddresses[floodslotnum].lasttime + net_connectfloodblockingtimeout.value)
+                       if (realtime < floodlist[floodslotnum].lasttime + floodtime)
                        {
-                               // renew the ban on this address so it does not expire
-                               // until the flood has subsided
-                               sv.connectfloodaddresses[floodslotnum].lasttime = realtime;
+                               if(renew)
+                               {
+                                       // renew the ban on this address so it does not expire
+                                       // until the flood has subsided
+                                       floodlist[floodslotnum].lasttime = realtime;
+                               }
                                //Con_Printf("Flood detected!\n");
                                return true;
                        }
@@ -2530,27 +2535,27 @@ static qboolean NetConn_PreventConnectFlood(lhnetaddress_t *peeraddress)
                }
        }
        // begin a new timeout on this address
-       sv.connectfloodaddresses[bestfloodslotnum].address = noportpeeraddress;
-       sv.connectfloodaddresses[bestfloodslotnum].lasttime = realtime;
+       floodlist[bestfloodslotnum].address = noportpeeraddress;
+       floodlist[bestfloodslotnum].lasttime = realtime;
        //Con_Printf("Flood detection initiated!\n");
        return false;
 }
 
-void NetConn_ClearConnectFlood(lhnetaddress_t *peeraddress)
+void NetConn_ClearFlood(lhnetaddress_t *peeraddress, server_floodaddress_t *floodlist, size_t floodlength)
 {
-       int floodslotnum;
+       size_t floodslotnum;
        lhnetaddress_t noportpeeraddress;
        // see if this is a connect flood
        noportpeeraddress = *peeraddress;
        LHNETADDRESS_SetPort(&noportpeeraddress, 0);
-       for (floodslotnum = 0;floodslotnum < MAX_CONNECTFLOODADDRESSES;floodslotnum++)
+       for (floodslotnum = 0;floodslotnum < floodlength;floodslotnum++)
        {
-               if (sv.connectfloodaddresses[floodslotnum].lasttime && LHNETADDRESS_Compare(&noportpeeraddress, &sv.connectfloodaddresses[floodslotnum].address) == 0)
+               if (floodlist[floodslotnum].lasttime && LHNETADDRESS_Compare(&noportpeeraddress, &floodlist[floodslotnum].address) == 0)
                {
                        // this address matches an ongoing flood address
                        // remove the ban
-                       sv.connectfloodaddresses[floodslotnum].address.addresstype = LHNETADDRESSTYPE_NONE;
-                       sv.connectfloodaddresses[floodslotnum].lasttime = 0;
+                       floodlist[floodslotnum].address.addresstype = LHNETADDRESSTYPE_NONE;
+                       floodlist[floodslotnum].lasttime = 0;
                        //Con_Printf("Flood cleared!\n");
                }
        }
@@ -2835,6 +2840,12 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                                challenge[i].address = *peeraddress;
                                NetConn_BuildChallengeString(challenge[i].string, sizeof(challenge[i].string));
                        }
+                       else
+                       {
+                               // flood control: drop if requesting challenge too often
+                               if(challenge[i].time < realtime - net_challengefloodblockingtimeout.value)
+                                       return true;
+                       }
                        challenge[i].time = realtime;
                        // send the challenge
                        dpsnprintf(response, sizeof(response), "\377\377\377\377challenge %s", challenge[i].string);
@@ -2964,7 +2975,7 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                                }
                        }
 
-                       if (NetConn_PreventConnectFlood(peeraddress))
+                       if (NetConn_PreventFlood(peeraddress, sv.connectfloodaddresses, sizeof(sv.connectfloodaddresses) / sizeof(sv.connectfloodaddresses[0]), net_connectfloodblockingtimeout.value, true))
                                return true;
 
                        // find an empty client slot for this new client
@@ -2997,6 +3008,9 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                {
                        const char *challenge = NULL;
 
+                       if (NetConn_PreventFlood(peeraddress, sv.getstatusfloodaddresses, sizeof(sv.getstatusfloodaddresses) / sizeof(sv.getstatusfloodaddresses[0]), net_getstatusfloodblockingtimeout.value, false))
+                               return true;
+
                        // If there was a challenge in the getinfo message
                        if (length > 8 && string[7] == ' ')
                                challenge = string + 8;
@@ -3013,6 +3027,9 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                {
                        const char *challenge = NULL;
 
+                       if (NetConn_PreventFlood(peeraddress, sv.getstatusfloodaddresses, sizeof(sv.getstatusfloodaddresses) / sizeof(sv.getstatusfloodaddresses[0]), net_getstatusfloodblockingtimeout.value, false))
+                               return true;
+
                        // If there was a challenge in the getinfo message
                        if (length > 10 && string[9] == ' ')
                                challenge = string + 10;
@@ -3187,7 +3204,7 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                        }
 
                        // this is a new client, check for connection flood
-                       if (NetConn_PreventConnectFlood(peeraddress))
+                       if (NetConn_PreventFlood(peeraddress, sv.connectfloodaddresses, sizeof(sv.connectfloodaddresses) / sizeof(sv.connectfloodaddresses[0]), net_connectfloodblockingtimeout.value, true))
                                break;
 
                        // find a slot for the new client
@@ -3234,6 +3251,10 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                                Con_DPrintf("Datagram_ParseConnectionless: received CCREQ_SERVER_INFO from %s.\n", addressstring2);
                        if(!(islocal || sv_public.integer > -1))
                                break;
+
+                       if (NetConn_PreventFlood(peeraddress, sv.getstatusfloodaddresses, sizeof(sv.getstatusfloodaddresses) / sizeof(sv.getstatusfloodaddresses[0]), net_getstatusfloodblockingtimeout.value, false))
+                               break;
+
                        if (sv.active && !strcmp(MSG_ReadString(&sv_message, sv_readstring, sizeof(sv_readstring)), "QUAKE"))
                        {
                                int numclients;
@@ -3265,6 +3286,10 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                                Con_DPrintf("Datagram_ParseConnectionless: received CCREQ_PLAYER_INFO from %s.\n", addressstring2);
                        if(!(islocal || sv_public.integer > -1))
                                break;
+
+                       if (NetConn_PreventFlood(peeraddress, sv.getstatusfloodaddresses, sizeof(sv.getstatusfloodaddresses) / sizeof(sv.getstatusfloodaddresses[0]), net_getstatusfloodblockingtimeout.value, false))
+                               break;
+
                        if (sv.active)
                        {
                                int playerNumber, activeNumber, clientNumber;
@@ -3301,6 +3326,9 @@ static int NetConn_ServerParsePacket(lhnetsocket_t *mysocket, unsigned char *dat
                                Con_DPrintf("Datagram_ParseConnectionless: received CCREQ_RULE_INFO from %s.\n", addressstring2);
                        if(!(islocal || sv_public.integer > -1))
                                break;
+
+                       // no flood check here, as it only returns one cvar for one cvar and clients may iterate quickly
+
                        if (sv.active)
                        {
                                char *prevCvarName;
@@ -3645,6 +3673,8 @@ void NetConn_Init(void)
        Cvar_RegisterVariable(&net_messagetimeout);
        Cvar_RegisterVariable(&net_connecttimeout);
        Cvar_RegisterVariable(&net_connectfloodblockingtimeout);
+       Cvar_RegisterVariable(&net_challengefloodblockingtimeout);
+       Cvar_RegisterVariable(&net_getstatusfloodblockingtimeout);
        Cvar_RegisterVariable(&cl_netlocalping);
        Cvar_RegisterVariable(&cl_netpacketloss_send);
        Cvar_RegisterVariable(&cl_netpacketloss_receive);

diff --git a/server.h b/server.h
index 321185634c1ade6bb2d0521794f0934ff097e416..3be5510ef64b9a0710631889249fdb5d939ecf79 100644 (file)
--- a/server.h
+++ b/server.h
@@ -66,12 +66,13 @@ typedef struct server_static_s
 typedef enum server_state_e {ss_loading, ss_active} server_state_t;
 
 #define MAX_CONNECTFLOODADDRESSES 16
-typedef struct server_connectfloodaddress_s
+#define MAX_GETSTATUSFLOODADDRESSES 128
+typedef struct server_floodaddress_s
 {
        double lasttime;
        lhnetaddress_t address;
 }
-server_connectfloodaddress_t;
+server_floodaddress_t;
 
 typedef struct server_s
 {
@@ -137,7 +138,8 @@ typedef struct server_s
        /// connection flood blocking
        /// note this is in server_t rather than server_static_t so that it is
        /// reset on each map command (such as New Game in singleplayer)
-       server_connectfloodaddress_t connectfloodaddresses[MAX_CONNECTFLOODADDRESSES];
+       server_floodaddress_t connectfloodaddresses[MAX_CONNECTFLOODADDRESSES];
+       server_floodaddress_t getstatusfloodaddresses[MAX_GETSTATUSFLOODADDRESSES];
 
 #define SV_MAX_PARTICLEEFFECTNAME 256
        qboolean particleeffectnamesloaded;