/*
=================
SV_VerifyPaks_f
If we are pure, disconnect the client if they do no meet the following conditions:
1. the first two checksums match our view of cgame and ui
2. there are no any additional checksums that we do not have
This routine would be a bit simpler with a goto but i abstained
=================
*/
static void SV_VerifyPaks_f( client_t *cl ) {
int nChkSum1, nChkSum2, nClientPaks, nServerPaks, i, j, nCurArg;
int nClientChkSum[1024];
int nServerChkSum[1024];
const char *pPaks, *pArg;
qboolean bGood = qtrue;
// if we are pure, we "expect" the client to load certain things from
// certain pk3 files, namely we want the client to have loaded the
// ui and cgame that we think should be loaded based on the pure setting
//
if ( sv_pure->integer != 0 ) {
bGood = qtrue;
nChkSum1 = nChkSum2 = 0;
// we run the game, so determine which cgame and ui the client "should" be running
//dlls are valid too now -rww
if (Cvar_VariableValue( "vm_cgame" ))
{
bGood = (qboolean)(FS_FileIsInPAK("vm/cgame.qvm", &nChkSum1) == 1);
}
else
{
bGood = (qboolean)(FS_FileIsInPAK("cgamex86.dll", &nChkSum1) == 1);
}
if (bGood)
{
if (Cvar_VariableValue( "vm_ui" ))
{
bGood = (qboolean)(FS_FileIsInPAK("vm/ui.qvm", &nChkSum2) == 1);
}
else
{
bGood = (qboolean)(FS_FileIsInPAK("uix86.dll", &nChkSum2) == 1);
}
}
nClientPaks = Cmd_Argc();
// start at arg 1 ( skip cl_paks )
nCurArg = 1;
// we basically use this while loop to avoid using 'goto' :)
while (bGood) {
// must be at least 6: "cl_paks cgame ui @ firstref ... numChecksums"
// numChecksums is encoded
if (nClientPaks < 6) {
bGood = qfalse;
break;
}
// verify first to be the cgame checksum
pArg = Cmd_Argv(nCurArg++);
if (!pArg || *pArg == '@' || atoi(pArg) != nChkSum1 ) {
bGood = qfalse;
break;
}
// verify the second to be the ui checksum
pArg = Cmd_Argv(nCurArg++);
if (!pArg || *pArg == '@' || atoi(pArg) != nChkSum2 ) {
bGood = qfalse;
break;
}
// should be sitting at the delimeter now
pArg = Cmd_Argv(nCurArg++);
if (*pArg != '@') {
bGood = qfalse;
break;
}
// store checksums since tokenization is not re-entrant
for (i = 0; nCurArg < nClientPaks; i++) {
nClientChkSum[i] = atoi(Cmd_Argv(nCurArg++));
}
// store number to compare against (minus one cause the last is the number of checksums)
nClientPaks = i - 1;
// make sure none of the client check sums are the same
// so the client can't send 5 the same checksums
for (i = 0; i < nClientPaks; i++) {
for (j = 0; j < nClientPaks; j++) {
if (i == j)
continue;
if (nClientChkSum[i] == nClientChkSum[j]) {
bGood = qfalse;
break;
}
}
if (bGood == qfalse)
break;
}
if (bGood == qfalse)
break;
// get the pure checksums of the pk3 files loaded by the server
pPaks = FS_LoadedPakPureChecksums();
Cmd_TokenizeString( pPaks );
nServerPaks = Cmd_Argc();
if (nServerPaks > 1024)
nServerPaks = 1024;
for (i = 0; i < nServerPaks; i++) {
nServerChkSum[i] = atoi(Cmd_Argv(i));
}
// check if the client has provided any pure checksums of pk3 files not loaded by the server
for (i = 0; i < nClientPaks; i++) {
for (j = 0; j < nServerPaks; j++) {
if (nClientChkSum[i] == nServerChkSum[j]) {
break;
}
}
if (j >= nServerPaks) {
bGood = qfalse;
break;
}
}
if ( bGood == qfalse ) {
break;
}
// check if the number of checksums was correct
nChkSum1 = sv.checksumFeed;
for (i = 0; i < nClientPaks; i++) {
nChkSum1 ^= nClientChkSum[i];
}
nChkSum1 ^= nClientPaks;
if (nChkSum1 != nClientChkSum[nClientPaks]) {
bGood = qfalse;
break;
}
// break out
break;
}
if (bGood) {
cl->pureAuthentic = 1;
}
else {
cl->pureAuthentic = 0;
cl->nextSnapshotTime = -1;
cl->state = CS_ACTIVE;
SV_SendClientSnapshot( cl );
SV_DropClient( cl, "Unpure client detected. Invalid .PK3 files referenced!" );
}
}
}
/*
=================
SV_VerifyPaks_f
If we are pure, disconnect the client if they do no meet the following conditions:
1. the first two checksums match our view of cgame and ui
2. there are no any additional checksums that we do not have
This routine would be a bit simpler with a goto but i abstained
=================
*/
static void SV_VerifyPaks_f( client_t *cl ) {
int nChkSum1, nChkSum2, nClientPaks, nServerPaks, i, j, nCurArg;
int nClientChkSum[1024];
int nServerChkSum[1024];
const char *pPaks, *pArg;
qboolean bGood = qtrue;
// if we are pure, we "expect" the client to load certain things from
// certain pk3 files, namely we want the client to have loaded the
// ui and cgame that we think should be loaded based on the pure setting
//
if ( sv_pure->integer != 0 ) {
bGood = qtrue;
nChkSum1 = nChkSum2 = 0;
// we run the game, so determine which cgame and ui the client "should" be running
bGood = (FS_FileIsInPAK("vm/cgame.qvm", &nChkSum1) == 1);
if (bGood)
bGood = (FS_FileIsInPAK("vm/ui.qvm", &nChkSum2) == 1);
nClientPaks = Cmd_Argc();
// start at arg 2 ( skip serverId cl_paks )
nCurArg = 1;
pArg = Cmd_Argv(nCurArg++);
if(!pArg) {
bGood = qfalse;
}
else
{
// https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=475
// we may get incoming cp sequences from a previous checksumFeed, which we need to ignore
// since serverId is a frame count, it always goes up
if (atoi(pArg) < sv.checksumFeedServerId)
{
Com_DPrintf("ignoring outdated cp command from client %s\n", cl->name);
return;
}
}
// we basically use this while loop to avoid using 'goto' :)
while (bGood) {
// must be at least 6: "cl_paks cgame ui @ firstref ... numChecksums"
// numChecksums is encoded
if (nClientPaks < 6) {
bGood = qfalse;
break;
}
// verify first to be the cgame checksum
pArg = Cmd_Argv(nCurArg++);
if (!pArg || *pArg == '@' || atoi(pArg) != nChkSum1 ) {
bGood = qfalse;
break;
}
// verify the second to be the ui checksum
pArg = Cmd_Argv(nCurArg++);
if (!pArg || *pArg == '@' || atoi(pArg) != nChkSum2 ) {
bGood = qfalse;
break;
}
// should be sitting at the delimeter now
pArg = Cmd_Argv(nCurArg++);
if (*pArg != '@') {
bGood = qfalse;
break;
}
// store checksums since tokenization is not re-entrant
for (i = 0; nCurArg < nClientPaks; i++) {
nClientChkSum[i] = atoi(Cmd_Argv(nCurArg++));
}
// store number to compare against (minus one cause the last is the number of checksums)
nClientPaks = i - 1;
// make sure none of the client check sums are the same
// so the client can't send 5 the same checksums
for (i = 0; i < nClientPaks; i++) {
for (j = 0; j < nClientPaks; j++) {
if (i == j)
continue;
if (nClientChkSum[i] == nClientChkSum[j]) {
bGood = qfalse;
break;
}
}
if (bGood == qfalse)
break;
}
if (bGood == qfalse)
break;
// get the pure checksums of the pk3 files loaded by the server
pPaks = FS_LoadedPakPureChecksums();
Cmd_TokenizeString( pPaks );
nServerPaks = Cmd_Argc();
if (nServerPaks > 1024)
nServerPaks = 1024;
for (i = 0; i < nServerPaks; i++) {
nServerChkSum[i] = atoi(Cmd_Argv(i));
}
// check if the client has provided any pure checksums of pk3 files not loaded by the server
for (i = 0; i < nClientPaks; i++) {
for (j = 0; j < nServerPaks; j++) {
if (nClientChkSum[i] == nServerChkSum[j]) {
break;
}
}
if (j >= nServerPaks) {
bGood = qfalse;
break;
}
}
if ( bGood == qfalse ) {
break;
}
// check if the number of checksums was correct
nChkSum1 = sv.checksumFeed;
for (i = 0; i < nClientPaks; i++) {
nChkSum1 ^= nClientChkSum[i];
}
nChkSum1 ^= nClientPaks;
if (nChkSum1 != nClientChkSum[nClientPaks]) {
bGood = qfalse;
break;
}
// break out
break;
}
cl->gotCP = qtrue;
if (bGood) {
cl->pureAuthentic = 1;
}
else {
cl->pureAuthentic = 0;
cl->nextSnapshotTime = -1;
cl->state = CS_ACTIVE;
SV_SendClientSnapshot( cl );
SV_DropClient( cl, "Unpure client detected. Invalid .PK3 files referenced!" );
}
}
}