Prevent Autocomplete Quest Packet-Editing Exploit (#844)

vmangos · May 24, 2017 · 6c84ff7 · 6c84ff7
1 parent 0858eaf
commit 6c84ff7
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Showing 3 changed files with 23 additions and 8 deletions.
diff --git a/src/game/Handlers/QuestHandler.cpp b/src/game/Handlers/QuestHandler.cpp
@@ -279,7 +279,9 @@ void WorldSession::HandleQuestgiverChooseRewardOpcode(WorldPacket & recv_data)
                 _player->PlayerTalkClass->SendQuestGiverQuestDetails(nextquest, guid, true);
         }
         else
+        {
             _player->PlayerTalkClass->SendQuestGiverOfferReward(pQuest, guid, true);
+        }
     }
 }
 

diff --git a/src/game/Objects/Player.cpp b/src/game/Objects/Player.cpp
@@ -12072,12 +12072,12 @@ bool Player::CanSeeStartQuest(Quest const *pQuest) const
     return false;
 }
 
-bool Player::CanTakeQuest(Quest const *pQuest, bool msg) const
+bool Player::CanTakeQuest(Quest const *pQuest, bool msg, bool skipStatusCheck /*false*/) const
 {
     if (pQuest->GetType() == QUEST_TYPE_PVP && pQuest->GetQuestLevel() && pQuest->GetQuestLevel() < getLevel())
         return false;
 
-    return SatisfyQuestStatus(pQuest, msg) && SatisfyQuestExclusiveGroup(pQuest, msg) &&
+    return (skipStatusCheck || SatisfyQuestStatus(pQuest, msg)) && SatisfyQuestExclusiveGroup(pQuest, msg) &&
            SatisfyQuestClass(pQuest, msg) && SatisfyQuestRace(pQuest, msg) && SatisfyQuestLevel(pQuest, msg) &&
            SatisfyQuestSkill(pQuest, msg) && SatisfyQuestReputation(pQuest, msg) &&
            SatisfyQuestPreviousQuest(pQuest, msg) && SatisfyQuestTimed(pQuest, msg) &&
@@ -12196,11 +12196,21 @@ bool Player::CanCompleteRepeatableQuest(Quest const *pQuest) const
 
 bool Player::CanRewardQuest(Quest const *pQuest, bool msg) const
 {
-    // not auto complete quest and not completed quest (only cheating case, then ignore without message)
-    if (!pQuest->IsAutoComplete() && GetQuestStatus(pQuest->GetQuestId()) != QUEST_STATUS_COMPLETE)
-        return false;
+    // Prevent packet-editing exploits
+    // Players must meet prereqs for AutoComplete quests
+    if (pQuest->IsAutoComplete())
+    {
+        if (!CanTakeQuest(pQuest, false, true))
+            return false;
+    }
+    else
+    {
+        // Normal quests must be accepted and have a complete status
+        if (GetQuestStatus(pQuest->GetQuestId()) != QUEST_STATUS_COMPLETE)
+            return false;
+    }
 
-    // rewarded and not repeatable quest (only cheating case, then ignore without message)
+    // Prevent completing the same quest twice
     if (GetQuestRewardStatus(pQuest->GetQuestId()))
         return false;
 
@@ -12219,9 +12229,12 @@ bool Player::CanRewardQuest(Quest const *pQuest, bool msg) const
         }
     }
 
-    // prevent receive reward with low money and GetRewOrReqMoney() < 0
+    // Check if players have enough money to complete the quest
     if (pQuest->GetRewOrReqMoney() < 0 && GetMoney() < uint32(-pQuest->GetRewOrReqMoney()))
+    {
+        SendCanTakeQuestResponse(INVALIDREASON_QUEST_FAILED_NOT_ENOUGH_MONEY);
         return false;
+    }
 
     return true;
 }

diff --git a/src/game/Objects/Player.h b/src/game/Objects/Player.h
@@ -1201,7 +1201,7 @@ class MANGOS_DLL_SPEC Player final: public Unit
         bool IsCurrentQuest(uint32 quest_id, uint8 completedOrNot = 0) const;
         Quest const *GetNextQuest(ObjectGuid guid, Quest const *pQuest );
         bool CanSeeStartQuest( Quest const *pQuest ) const;
-        bool CanTakeQuest( Quest const *pQuest, bool msg ) const;
+        bool CanTakeQuest( Quest const *pQuest, bool msg, bool skipStatusCheck = false ) const;
         bool CanAddQuest( Quest const *pQuest, bool msg ) const;
         bool CanCompleteQuest( uint32 quest_id ) const;
         bool CanCompleteRepeatableQuest(Quest const *pQuest) const;
-Original file line number
+Diff line change
@@ Expand Up @@
                     _player->PlayerTalkClass->SendQuestGiverQuestDetails(nextquest, guid, true);
             }
             else
+            {
                 _player->PlayerTalkClass->SendQuestGiverOfferReward(pQuest, guid, true);
+            }
         }
     }
@@ Expand Down @@