From 0761ade4ae730ee96bc6b738fa563f0ecf2e4084 Mon Sep 17 00:00:00 2001
From: Darren Ranalli <github@dranalli.com>
Date: Fri, 10 Oct 2003 22:54:39 +0000
Subject: [PATCH] AI and client check entTypeReg hashes

---
 direct/src/level/DistributedLevel.py   |  7 ++++++-
 direct/src/level/DistributedLevelAI.py | 14 +++++++++++++-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/direct/src/level/DistributedLevel.py b/direct/src/level/DistributedLevel.py
index dea76124b9..578b9c78a9 100755
--- a/direct/src/level/DistributedLevel.py
+++ b/direct/src/level/DistributedLevel.py
@@ -112,11 +112,16 @@ class DistributedLevel(DistributedObject.DistributedObject,
             # if we're in debug, give the server the opportunity to send us
             # a full spec
             self.candidateSpec = levelSpec
-            self.sendUpdate('requestCurrentLevelSpec', [hash(levelSpec)])
+            self.sendUpdate('requestCurrentLevelSpec',
+                            [hash(levelSpec),
+                             hash(levelSpec.entTypeReg)])
         else:
             self.privGotSpec(levelSpec)
 
     if __debug__:
+        def setSpecDeny(self, reason):
+            DistributedLevel.notify.error(reason)
+            
         def setSpecSenderDoId(self, doId):
             DistributedLevel.notify.debug('setSpecSenderDoId: %s' % doId)
             blobSender = toonbase.tcr.doId2do[doId]
diff --git a/direct/src/level/DistributedLevelAI.py b/direct/src/level/DistributedLevelAI.py
index 95bf627c06..7540e34233 100755
--- a/direct/src/level/DistributedLevelAI.py
+++ b/direct/src/level/DistributedLevelAI.py
@@ -116,8 +116,20 @@ class DistributedLevelAI(DistributedObjectAI.DistributedObjectAI,
                 self.levelSpec.saveToDisk()
                 self.modified = 0
 
-        def requestCurrentLevelSpec(self, specHash):
+        def requestCurrentLevelSpec(self, specHash, entTypeRegHash):
             senderId = self.air.msgSender
+
+            # first check the typeReg hash -- if it doesn't match, the
+            # client should not be connecting. Their entityTypeRegistry
+            # is different from ours.
+            srvHash = hash(self.levelSpec.entTypeReg)
+            if srvHash != entTypeRegHash:
+                self.sendUpdateToAvatarId(
+                    senderId, 'setSpecDeny',
+                    ['EntityTypeRegistry hashes do not match! '
+                     '(server:%s, client:%s' % (srvHash, entTypeRegHash)])
+                return
+            
             spec = None
             if hash(self.levelSpec) != specHash:
                 spec = self.levelSpec