Core/WorldSession: Added research notes about CMSG_AUTH_SESSION values and reordered checks during login to always initialize encryption first to make sure the client can read failure packet

3 files changed, 82 insertions, 61 deletions

diff --git a/src/server/authserver/Server/AuthSession.cpp b/src/server/authserver/Server/AuthSession.cpp
index 9931595e860..8276183fb10 100644
--- a/src/server/authserver/Server/AuthSession.cpp
+++ b/src/server/authserver/Server/AuthSession.cpp
@@ -83,8 +83,8 @@ typedef struct AUTH_LOGON_PROOF_S
     uint8   cmd;
     uint8   error;
     uint8   M2[20];
-    uint32  unk1;
-    uint32  unk2;
+    uint32  AccountFlags;
+    uint32  SurveyId;
     uint16  unk3;
 } sAuthLogonProof_S;
 
@@ -540,9 +540,9 @@ bool AuthSession::HandleLogonProof()
             memcpy(proof.M2, sha.GetDigest(), 20);
             proof.cmd = AUTH_LOGON_PROOF;
             proof.error = 0;
-            proof.unk1 = 0x00800000;    // Accountflags. 0x01 = GM, 0x08 = Trial, 0x00800000 = Pro pass (arena tournament)
-            proof.unk2 = 0x00;          // SurveyId
-            proof.unk3 = 0x00;
+            proof.AccountFlags = 0x00800000;    // 0x01 = GM, 0x08 = Trial, 0x00800000 = Pro pass (arena tournament)
+            proof.SurveyId = 0;
+            proof.unk3 = 0;
 
             packet.resize(sizeof(proof));
             std::memcpy(packet.contents(), &proof, sizeof(proof));
@@ -831,7 +831,7 @@ bool AuthSession::HandleRealmList()
         pkt << AmountOfCharacters;
         pkt << realm.timezone;                              // realm category
         if (_expversion & POST_BC_EXP_FLAG)                 // 2.x and 3.x clients
-            pkt << uint8(0x2C);                             // unk, may be realm number/id?
+            pkt << uint8(realm.m_ID);
         else
             pkt << uint8(0x0);                              // 1.12.1 and 1.12.2 clients
 
diff --git a/src/server/game/Server/WorldSocket.cpp b/src/server/game/Server/WorldSocket.cpp
index 5945d9fe868..ca8e2cd5a34 100644
--- a/src/server/game/Server/WorldSocket.cpp
+++ b/src/server/game/Server/WorldSocket.cpp
@@ -87,8 +87,6 @@ void WorldSocket::ReadDataHandler()
 {
     ClientPktHeader* header = reinterpret_cast<ClientPktHeader*>(GetHeaderBuffer());
 
-    header->size -= sizeof(header->cmd);
-
     uint16 opcode = uint16(header->cmd);
 
     std::string opcodeName = GetOpcodeNameForLogging(opcode);
@@ -173,35 +171,30 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
     std::string account;
     SHA1Hash sha;
     uint32 clientBuild;
-    uint32 unk2, unk3, unk5, unk6, unk7;
+    uint32 serverId, loginServerType, region, battlegroup, realmIndex;
     uint64 unk4;
     WorldPacket packet, SendAddonPacked;
     BigNumber k;
     bool wardenActive = sWorld->getBoolConfig(CONFIG_WARDEN_ENABLED);
 
-    if (sWorld->IsClosed())
-    {
-        SendAuthResponseError(AUTH_REJECT);
-        TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: World closed, denying client (%s).", GetRemoteIpAddress().to_string().c_str());
-        return;
-    }
-
     // Read the content of the packet
     recvPacket >> clientBuild;
-    recvPacket >> unk2;
+    recvPacket >> serverId;                 // Used for GRUNT only
     recvPacket >> account;
-    recvPacket >> unk3;
+    recvPacket >> loginServerType;          // 0 GRUNT, 1 Battle.net
     recvPacket >> clientSeed;
-    recvPacket >> unk5 >> unk6 >> unk7;
+    recvPacket >> region >> battlegroup;    // Used for Battle.net only
+    recvPacket >> realmIndex;               // realmId from auth_database.realmlist table
     recvPacket >> unk4;
     recvPacket.read(digest, 20);
 
-    TC_LOG_DEBUG("network", "WorldSocket::HandleAuthSession: client %u, unk2 %u, account %s, unk3 %u, clientseed %u",
+    TC_LOG_INFO("network", "WorldSocket::HandleAuthSession: client %u, serverId %u, account %s, loginServerType %u, clientseed %u, realmIndex %u",
         clientBuild,
-        unk2,
+        serverId,
         account.c_str(),
-        unk3,
-        clientSeed);
+        loginServerType,
+        clientSeed,
+        realmIndex);
 
     // Get the account information from the auth database
     //         0           1        2       3          4         5       6          7   8
@@ -218,6 +211,7 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
         // We can not log here, as we do not know the account. Thus, no accountId.
         SendAuthResponseError(AUTH_UNKNOWN_ACCOUNT);
         TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Sent Auth Response (unknown account).");
+        DelayedCloseSocket();
         return;
     }
 
@@ -243,6 +237,57 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
     // id has to be fetched at this point, so that first actual account response that fails can be logged
     id = fields[0].GetUInt32();
 
+    k.SetHexStr(fields[1].GetCString());
+
+    // even if auth credentials are bad, try using the session key we have - client cannot read auth response error without it
+    _authCrypt.Init(&k);
+
+    // First reject the connection if packet contains invalid data or realm state doesn't allow logging in
+    if (sWorld->IsClosed())
+    {
+        SendAuthResponseError(AUTH_REJECT);
+        TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: World closed, denying client (%s).", GetRemoteIpAddress().to_string().c_str());
+        DelayedCloseSocket();
+        return;
+    }
+
+    if (realmIndex != realmID)
+    {
+        SendAuthResponseError(REALM_LIST_REALM_NOT_FOUND);
+        TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Sent Auth Response (bad realm).");
+        DelayedCloseSocket();
+        return;
+    }
+
+    std::string os = fields[8].GetString();
+
+    // Must be done before WorldSession is created
+    if (wardenActive && os != "Win" && os != "OSX")
+    {
+        SendAuthResponseError(AUTH_REJECT);
+        TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Client %s attempted to log in using invalid client OS (%s).", address.c_str(), os.c_str());
+        DelayedCloseSocket();
+        return;
+    }
+
+    // Check that Key and account name are the same on client and server
+    uint32 t = 0;
+
+    sha.UpdateData(account);
+    sha.UpdateData((uint8*)&t, 4);
+    sha.UpdateData((uint8*)&clientSeed, 4);
+    sha.UpdateData((uint8*)&_authSeed, 4);
+    sha.UpdateBigNumbers(&k, NULL);
+    sha.Finalize();
+
+    if (memcmp(sha.GetDigest(), digest, 20))
+    {
+        SendAuthResponseError(AUTH_FAILED);
+        TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Authentication failed for account: %u ('%s') address: %s", id, account.c_str(), address.c_str());
+        DelayedCloseSocket();
+        return;
+    }
+
     ///- Re-check ip locking (same check as in auth).
     if (fields[3].GetUInt8() == 1) // if ip is locked
     {
@@ -252,12 +297,11 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
             TC_LOG_DEBUG("network", "WorldSocket::HandleAuthSession: Sent Auth Response (Account IP differs. Original IP: %s, new IP: %s).", fields[2].GetCString(), address.c_str());
             // We could log on hook only instead of an additional db log, however action logger is config based. Better keep DB logging as well
             sScriptMgr->OnFailedAccountLogin(id);
+            DelayedCloseSocket();
             return;
         }
     }
 
-    k.SetHexStr(fields[1].GetCString());
-
     int64 mutetime = fields[5].GetInt64();
     //! Negative mutetime indicates amount of seconds to be muted effective on next login - which is now.
     if (mutetime < 0)
@@ -277,16 +321,6 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
         locale = LOCALE_enUS;
 
     uint32 recruiter = fields[7].GetUInt32();
-    std::string os = fields[8].GetString();
-
-    // Must be done before WorldSession is created
-    if (wardenActive && os != "Win" && os != "OSX")
-    {
-        SendAuthResponseError(AUTH_REJECT);
-        TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Client %s attempted to log in using invalid client OS (%s).", address.c_str(), os.c_str());
-        return;
-    }
-
     // Checks gmlevel per Realm
     stmt = LoginDatabase.GetPreparedStatement(LOGIN_GET_GMLEVEL_BY_REALMID);
 
@@ -316,6 +350,7 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
         SendAuthResponseError(AUTH_BANNED);
         TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Sent Auth Response (Account banned).");
         sScriptMgr->OnFailedAccountLogin(id);
+        DelayedCloseSocket();
         return;
     }
 
@@ -327,23 +362,7 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
         SendAuthResponseError(AUTH_UNAVAILABLE);
         TC_LOG_INFO("network", "WorldSocket::HandleAuthSession: User tries to login but his security level is not enough");
         sScriptMgr->OnFailedAccountLogin(id);
-        return;
-    }
-
-    // Check that Key and account name are the same on client and server
-    uint32 t = 0;
-
-    sha.UpdateData(account);
-    sha.UpdateData((uint8*)&t, 4);
-    sha.UpdateData((uint8*)&clientSeed, 4);
-    sha.UpdateData((uint8*)&_authSeed, 4);
-    sha.UpdateBigNumbers(&k, NULL);
-    sha.Finalize();
-
-    if (memcmp(sha.GetDigest(), digest, 20))
-    {
-        SendAuthResponseError(AUTH_FAILED);
-        TC_LOG_ERROR("network", "WorldSocket::HandleAuthSession: Authentication failed for account: %u ('%s') address: %s", id, account.c_str(), address.c_str());
+        DelayedCloseSocket();
         return;
     }
 
@@ -370,19 +389,15 @@ void WorldSocket::HandleAuthSession(WorldPacket& recvPacket)
 
     LoginDatabase.Execute(stmt);
 
-    // NOTE ATM the socket is single-threaded, have this in mind ...
-    _worldSession = new WorldSession(id, shared_from_this(), AccountTypes(security), expansion, mutetime, locale, recruiter, isRecruiter);
-
-    _authCrypt.Init(&k);
+    // At this point, we can safely hook a successful login
+    sScriptMgr->OnAccountLogin(id);
 
+    _worldSession = new WorldSession(id, shared_from_this(), AccountTypes(security), expansion, mutetime, locale, recruiter, isRecruiter);
     _worldSession->LoadGlobalAccountData();
     _worldSession->LoadTutorialsData();
     _worldSession->ReadAddonsInfo(recvPacket);
     _worldSession->LoadPermissions();
 
-    // At this point, we can safely hook a successful login
-    sScriptMgr->OnAccountLogin(id);
-
     // Initialize Warden system only if it is enabled by config
     if (wardenActive)
         _worldSession->InitWarden(&k, os);
diff --git a/src/server/shared/Networking/Socket.h b/src/server/shared/Networking/Socket.h
index a13a079ff6c..3bd30bd731b 100644
--- a/src/server/shared/Networking/Socket.h
+++ b/src/server/shared/Networking/Socket.h
@@ -42,7 +42,7 @@ class Socket : public std::enable_shared_from_this<T>
 
 public:
     Socket(tcp::socket&& socket, std::size_t headerSize) : _socket(std::move(socket)), _remoteAddress(_socket.remote_endpoint().address()),
-        _remotePort(_socket.remote_endpoint().port()), _readHeaderBuffer(), _readDataBuffer(), _closed(false)
+        _remotePort(_socket.remote_endpoint().port()), _readHeaderBuffer(), _readDataBuffer(), _closed(false), _closing(false)
     {
         _readHeaderBuffer.Grow(headerSize);
     }
@@ -126,7 +126,7 @@ public:
             std::placeholders::_1, std::placeholders::_2));
     }
 
-    bool IsOpen() const { return !_closed; }
+    bool IsOpen() const { return !_closed && !_closing; }
 
     virtual void CloseSocket()
     {
@@ -140,6 +140,9 @@ public:
                 shutdownError.value(), shutdownError.message().c_str());
     }
 
+    /// Marks the socket for closing after write buffer becomes empty
+    void DelayedCloseSocket() { _closing = true; }
+
     virtual bool IsHeaderReady() const { return _readHeaderBuffer.IsMessageReady(); }
     virtual bool IsDataReady() const { return _readDataBuffer.IsMessageReady(); }
 
@@ -221,6 +224,8 @@ private:
 
             if (!_writeQueue.empty())
                 AsyncWrite(_writeQueue.front());
+            else if (_closing)
+                CloseSocket();
         }
         else
             CloseSocket();
@@ -241,6 +246,7 @@ private:
     MessageBuffer _readDataBuffer;
 
     std::atomic<bool> _closed;
+    std::atomic<bool> _closing;
 };
 
 #endif // __SOCKET_H__