Core/Chat: move chat link validation code into separate classes and improve some validation logic

Core/Misc: fix non-pch build

1 files changed, 714 insertions, 0 deletions

diff --git a/src/server/game/Chat/ChatLink.cpp b/src/server/game/Chat/ChatLink.cpp
new file mode 100644
index 00000000000..95ac685548f
--- /dev/null
+++ b/src/server/game/Chat/ChatLink.cpp
@@ -0,0 +1,714 @@
+/*
+ * Copyright (C) 2008-2011 TrinityCore <http://www.trinitycore.org/>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "ChatLink.h"
+#include "SpellMgr.h"
+#include "ObjectMgr.h"
+
+#ifdef TRINITY_DEBUG
+    #define LOG(...) sLog->outDebug(LOG_FILTER_CHATSYS, __VA_ARGS__);
+#else
+    #define LOG(...)
+#endif
+
+// Supported shift-links (client generated and server side)
+// |color|Hachievement:achievement_id:player_guid:0:0:0:0:0:0:0:0|h[name]|h|r
+//                                                                        - client, item icon shift click, not used in server currently
+// |color|Harea:area_id|h[name]|h|r
+// |color|Hcreature:creature_guid|h[name]|h|r
+// |color|Hcreature_entry:creature_id|h[name]|h|r
+// |color|Henchant:recipe_spell_id|h[prof_name: recipe_name]|h|r          - client, at shift click in recipes list dialog
+// |color|Hgameevent:id|h[name]|h|r
+// |color|Hgameobject:go_guid|h[name]|h|r
+// |color|Hgameobject_entry:go_id|h[name]|h|r
+// |color|Hglyph:glyph_slot_id:glyph_prop_id|h[%s]|h|r                    - client, at shift click in glyphs dialog, GlyphSlot.dbc, GlyphProperties.dbc
+// |color|Hitem:item_id:perm_ench_id:gem1:gem2:gem3:0:0:0:0:reporter_level|h[name]|h|r
+//                                                                        - client, item icon shift click
+// |color|Hitemset:itemset_id|h[name]|h|r
+// |color|Hplayer:name|h[name]|h|r                                        - client, in some messages, at click copy only name instead link
+// |color|Hquest:quest_id:quest_level|h[name]|h|r                         - client, quest list name shift-click
+// |color|Hskill:skill_id|h[name]|h|r
+// |color|Hspell:spell_id|h[name]|h|r                                     - client, spellbook spell icon shift-click
+// |color|Htalent:talent_id,rank|h[name]|h|r                              - client, talent icon shift-click
+// |color|Htaxinode:id|h[name]|h|r
+// |color|Htele:id|h[name]|h|r
+// |color|Htitle:id|h[name]|h|r
+// |color|Htrade:spell_id:cur_value:max_value:unk3int:unk3str|h[name]|h|r - client, spellbook profession icon shift-click
+
+inline bool ReadUInt32(std::istringstream& iss, uint32& res)
+{
+    iss >> std::dec >> res;
+    return !iss.fail() && !iss.eof();
+}
+
+inline bool ReadInt32(std::istringstream& iss, int32& res)
+{
+    iss >> std::dec >> res;
+    return !iss.fail() && !iss.eof();
+}
+
+inline std::string ReadSkip(std::istringstream& iss, char term)
+{
+    std::string res;
+    char c = iss.peek();
+    while (c != term && c != '\0')
+    {
+        res += c;
+        iss.ignore(1);
+        c = iss.peek();
+    }
+    return res;
+}
+
+inline bool CheckDelimiter(std::istringstream& iss, char delimiter, const char* context)
+{
+    char c = iss.peek();
+    if (c != delimiter)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): invalid %s link structure ('%c' expected, '%c' found)", iss.str().c_str(), context, delimiter, c);
+        return false;
+    }
+    iss.ignore(1);
+    return true;
+}
+
+inline bool ReadHex(std::istringstream& iss, uint32& res, uint32 length)
+{
+    std::istringstream::pos_type pos = iss.tellg();
+    iss >> std::hex >> res;
+    uint32 size = uint32(iss.gcount());
+    if (length && uint32(iss.tellg() - pos) != length)
+        return false;
+    return !iss.fail() && !iss.eof();
+}
+
+#define DELIMITER ':'
+#define PIPE_CHAR '|'
+
+bool ChatLink::ValidateName(char* buffer, const char* context)
+{
+    _name = buffer;
+    return true;
+}
+
+// |color|Hitem:item_id:perm_ench_id:gem1:gem2:gem3:0:random_property:0:reporter_level|h[name]|h|r
+// |cffa335ee|Hitem:812:0:0:0:0:0:0:0:70|h[Glowing Brightwood Staff]|h|r
+bool ItemChatLink::Initialize(std::istringstream& iss)
+{
+    // Read item entry
+    uint32 itemEntry = 0;
+    if (!ReadUInt32(iss, itemEntry))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading item entry", iss.str().c_str());
+        return false;
+    }
+    // Validate item
+    _item = ObjectMgr::GetItemPrototype(itemEntry);
+    if (!_item)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid itemEntry %u in |item command", iss.str().c_str(), itemEntry);
+        return false;
+    }
+    // Validate item's color
+    if (_color != ItemQualityColors[_item->Quality])
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): linked item has color %u, but user claims %u", iss.str().c_str(), ItemQualityColors[_item->Quality], _color);
+        return false;
+    }
+    // Number of various item properties after item entry
+    const uint8 propsCount = 8;
+    const uint8 randomPropertyPosition = 5;
+    for (uint8 index = 0; index < propsCount; ++index)
+    {
+        if (!CheckDelimiter(iss, DELIMITER, "item"))
+            return false;
+
+        int32 id = 0;
+        if (!ReadInt32(iss, id))
+        {
+            LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading item property (%u)", iss.str().c_str(), index);
+            return false;
+        }
+        if (id && (index == randomPropertyPosition))
+        {
+            // Validate random property
+            if (id > 0)
+            {
+                _property = sItemRandomPropertiesStore.LookupEntry(id);
+                if (!_property)
+                {
+                    LOG("ChatHandler::isValidChatMessage('%s'): got invalid item property id %u in |item command", iss.str().c_str(), id);
+                    return false;
+                }
+            }
+            else if (id < 0)
+            {
+                _suffix = sItemRandomSuffixStore.LookupEntry(-id);
+                if (!_suffix)
+                {
+                    LOG("ChatHandler::isValidChatMessage('%s'): got invalid item suffix id %u in |item command", iss.str().c_str(), -id);
+                    return false;
+                }
+            }
+        }
+        _data[index] = id;
+    }
+    return true;
+}
+
+inline std::string ItemChatLink::_FormatName(uint8 index, ItemLocale const *locale, char* const* suffixStrings) const
+{
+    std::stringstream ss;
+    if (locale == NULL || index >= locale->Name.size())
+        ss << _item->Name1;
+    else
+        ss << locale->Name[index];
+    if (suffixStrings)
+        ss << " " << suffixStrings[index];
+    return ss.str();
+}
+
+bool ItemChatLink::ValidateName(char* buffer, const char* context)
+{
+    ChatLink::ValidateName(buffer, context);
+
+    char* const* suffixStrings = _suffix ? _suffix->nameSuffix : (_property ? _property->nameSuffix : NULL);
+
+    bool res = (_FormatName(LOCALE_enUS, NULL, suffixStrings) == buffer);
+    if (!res)
+    {
+        ItemLocale const *il = sObjectMgr->GetItemLocale(_item->ItemId);
+        for (uint8 index = LOCALE_koKR; index < TOTAL_LOCALES; ++index)
+        {
+            if (_FormatName(index, il, suffixStrings) == buffer)
+            {
+                res = true;
+                break;
+            }
+        }
+    }
+    if (!res)
+        LOG("ChatHandler::isValidChatMessage('%s'): linked item (id: %u) name wasn't found in any localization", context, _item->ItemId);
+    return res;
+}
+
+// |color|Hquest:quest_id:quest_level|h[name]|h|r
+// |cff808080|Hquest:2278:47|h[The Platinum Discs]|h|r
+bool QuestChatLink::Initialize(std::istringstream& iss)
+{
+    // Read quest id
+    uint32 questId = 0;
+    if (!ReadUInt32(iss, questId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading quest entry", iss.str().c_str());
+        return false;
+    }
+    // Validate quest
+    _quest = sObjectMgr->GetQuestTemplate(questId);
+    if (!_quest)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): quest template %u not found", iss.str().c_str(), questId);
+        return false;
+    }
+    // Check delimiter
+    if (!CheckDelimiter(iss, DELIMITER, "quest"))
+        return false;
+    // Read quest level
+    if (!ReadInt32(iss, _questLevel))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading quest level", iss.str().c_str());
+        return false;
+    }
+    // Validate quest level
+    if (_questLevel >= STRONG_MAX_LEVEL)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): quest level %d is too big", iss.str().c_str(), _questLevel);
+        return false;
+    }
+    return true;
+}
+
+bool QuestChatLink::ValidateName(char* buffer, const char* context)
+{
+    ChatLink::ValidateName(buffer, context);
+
+    bool res = (_quest->GetTitle() == buffer);
+    if (!res)
+        if (QuestLocale const *ql = sObjectMgr->GetQuestLocale(_quest->GetQuestId()))
+            for (uint8 i = 0; i < ql->Title.size(); i++)
+                if (ql->Title[i] == buffer)
+                {
+                    res = true;
+                    break;
+                }
+    if (!res)
+        LOG("ChatHandler::isValidChatMessage('%s'): linked quest (id: %u) title wasn't found in any localization", context, _quest->GetQuestId());
+    return res;
+}
+
+// |color|Hspell:spell_id|h[name]|h|r
+// |cff71d5ff|Hspell:21563|h[Command]|h|r
+bool SpellChatLink::Initialize(std::istringstream& iss)
+{
+    if (_color != CHAT_LINK_COLOR_SPELL)
+        return false;
+    // Read spell id
+    uint32 spellId = 0;
+    if (!ReadUInt32(iss, spellId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading spell entry", iss.str().c_str());
+        return false;
+    }
+    // Validate spell
+    _spell = sSpellStore.LookupEntry(spellId);
+    if (!_spell)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid spell id %u in |spell command", iss.str().c_str(), spellId);
+        return false;
+    }
+    return true;
+}
+
+bool SpellChatLink::ValidateName(char* buffer, const char* context)
+{
+    ChatLink::ValidateName(buffer, context);
+
+    // spells with that flag have a prefix of "$PROFESSION: "
+    if (_spell->Attributes & SPELL_ATTR0_TRADESPELL)
+    {
+        SkillLineAbilityMapBounds bounds = sSpellMgr->GetSkillLineAbilityMapBounds(_spell->Id);
+        if (bounds.first == bounds.second)
+        {
+            LOG("ChatHandler::isValidChatMessage('%s'): skill line not found for spell %u", context, _spell->Id);
+            return false;
+        }
+        SkillLineAbilityEntry const *skillInfo = bounds.first->second;
+        if (!skillInfo)
+        {
+            LOG("ChatHandler::isValidChatMessage('%s'): skill line ability not found for spell %u", context, _spell->Id);
+            return false;
+        }
+        SkillLineEntry const *skillLine = sSkillLineStore.LookupEntry(skillInfo->skillId);
+        if (!skillLine)
+        {
+            LOG("ChatHandler::isValidChatMessage('%s'): skill line not found for skill %u", context, skillInfo->skillId);
+            return false;
+        }
+
+        for (uint8 i = 0; i < TOTAL_LOCALES; ++i)
+        {
+            uint32 skillLineNameLength = strlen(skillLine->name[i]);
+            if (skillLineNameLength > 0 && strncmp(skillLine->name[i], buffer, skillLineNameLength) == 0)
+            {
+                // found the prefix, remove it to perform spellname validation below
+                // -2 = strlen(": ")
+                uint32 spellNameLength = strlen(buffer) - skillLineNameLength - 2;
+                memcpy(buffer, buffer + skillLineNameLength + 2, spellNameLength + 1);
+            }
+        }
+    }
+
+    bool res = false;
+    for (uint8 i = 0; i < TOTAL_LOCALES; ++i)
+        if (*_spell->SpellName[i] && strcmp(_spell->SpellName[i], buffer) == 0)
+        {
+            res = true;
+            break;
+        }
+
+    if (!res)
+        LOG("ChatHandler::isValidChatMessage('%s'): linked spell (id: %u) name wasn't found in any localization", context, _spell->Id);
+    return res;
+}
+
+// |color|Hachievement:achievement_id:player_guid:0:0:0:0:0:0:0:0|h[name]|h|r
+// |cffffff00|Hachievement:546:0000000000000001:0:0:0:-1:0:0:0:0|h[Safe Deposit]|h|r
+bool AchievementChatLink::Initialize(std::istringstream& iss)
+{
+    if (_color != CHAT_LINK_COLOR_ACHIEVEMENT)
+        return false;
+    // Read achievemnt Id
+    uint32 achievementId = 0;
+    if (!ReadUInt32(iss, achievementId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading achievement entry", iss.str().c_str());
+        return false;
+    }
+    // Validate achievement
+    _achievement = sAchievementStore.LookupEntry(achievementId);
+    if (!_achievement)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid achivement id %u in |achievement command", iss.str().c_str(), achievementId);
+        return false;
+    }
+    // Check delimiter
+    if (!CheckDelimiter(iss, DELIMITER, "achievement"))
+        return false;
+    // Read HEX
+    if (!ReadHex(iss, _guid, 0))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): invalid hexadecimal number while reading char's guid", iss.str().c_str());
+        return false;
+    }
+    // Skip progress
+    const uint8 propsCount = 8;
+    for (uint8 index = 0; index < propsCount; ++index)
+    {
+        if (!CheckDelimiter(iss, DELIMITER, "achievement"))
+            return false;
+
+        if (!ReadUInt32(iss, _data[index]))
+        {
+            LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading achievement property (%u)", iss.str().c_str(), index);
+            return false;
+        }
+    }
+    return true;
+}
+
+bool AchievementChatLink::ValidateName(char* buffer, const char* context)
+{
+    ChatLink::ValidateName(buffer, context);
+
+    bool res = false;
+    for (uint8 i = 0; i < TOTAL_LOCALES; ++i)
+        if (*_achievement->name[i] && strcmp(_achievement->name[i], buffer) == 0)
+        {
+            res = true;
+            break;
+        }
+
+    if (!res)
+        LOG("ChatHandler::isValidChatMessage('%s'): linked achievement (id: %u) name wasn't found in any localization", context, _achievement->ID);
+    return res;
+}
+
+// |color|Htrade:spell_id:cur_value:max_value:player_guid:base64_data|h[name]|h|r
+// |cffffd000|Htrade:4037:1:150:1:6AAAAAAAAAAAAAAAAAAAAAAOAADAAAAAAAAAAAAAAAAIAAAAAAAAA|h[Engineering]|h|r
+bool TradeChatLink::Initialize(std::istringstream& iss)
+{
+    if (_color != CHAT_LINK_COLOR_TRADE)
+        return false;
+    // Spell Id
+    uint32 spellId = 0;
+    if (!ReadUInt32(iss, spellId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading achievement entry", iss.str().c_str());
+        return false;
+    }
+    // Validate spell
+    _spell = sSpellStore.LookupEntry(spellId);
+    if (!_spell)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid spell id %u in |trade command", iss.str().c_str(), spellId);
+        return false;
+    }
+    // Check delimiter
+    if (!CheckDelimiter(iss, DELIMITER, "trade"))
+        return false;
+    // Minimum talent level
+    if (!ReadInt32(iss, _minSkillLevel))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading minimum talent level", iss.str().c_str());
+        return false;
+    }
+    // Check delimiter
+    if (!CheckDelimiter(iss, DELIMITER, "trade"))
+        return false;
+    // Maximum talent level
+    if (!ReadInt32(iss, _maxSkillLevel))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading maximum talent level", iss.str().c_str());
+        return false;
+    }
+    // Check delimiter
+    if (!CheckDelimiter(iss, DELIMITER, "trade"))
+        return false;
+    // Something hexadecimal
+    if (!ReadHex(iss, _guid, 0))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading achievement's owner guid", iss.str().c_str());
+        return false;
+    }
+    // Skip base64 encoded stuff
+    _base64 = ReadSkip(iss, PIPE_CHAR);
+    return true;
+}
+
+// |color|Htalent:talent_id:rank|h[name]|h|r
+// |cff4e96f7|Htalent:2232:-1|h[Taste for Blood]|h|r
+bool TalentChatLink::Initialize(std::istringstream& iss)
+{
+    if (_color != CHAT_LINK_COLOR_TALENT)
+        return false;
+    // Read talent entry
+    if (!ReadUInt32(iss, _talentId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading talent entry", iss.str().c_str());
+        return false;
+    }
+    // Validate talent
+    TalentEntry const *talentInfo = sTalentStore.LookupEntry(_talentId);
+    if (!talentInfo)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid talent id %u in |talent command", iss.str().c_str(), _talentId);
+        return false;
+    }
+    // Validate talent's spell
+    _spell = sSpellStore.LookupEntry(talentInfo->RankID[0]);
+    if (!_spell)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid spell id %u in |trade command", iss.str().c_str(), talentInfo->RankID[0]);
+        return false;
+    }
+    // Delimiter
+    if (!CheckDelimiter(iss, DELIMITER, "talent"))
+        return false;
+    // Rank
+    if (!ReadInt32(iss, _rankId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading talent rank", iss.str().c_str());
+        return false;
+    }
+    return true;
+}
+
+// |color|Henchant:recipe_spell_id|h[prof_name: recipe_name]|h|r
+// |cffffd000|Henchant:3919|h[Engineering: Rough Dynamite]|h|r
+bool EnchantmentChatLink::Initialize(std::istringstream& iss)
+{
+    if (_color != CHAT_LINK_COLOR_ENCHANT)
+        return false;
+    // Spell Id
+    uint32 spellId = 0;
+    if (!ReadUInt32(iss, spellId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading enchantment spell entry", iss.str().c_str());
+        return false;
+    }
+    // Validate spell
+    _spell = sSpellStore.LookupEntry(spellId);
+    if (!_spell)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid spell id %u in |enchant command", iss.str().c_str(), spellId);
+        return false;
+    }
+    return true;
+}
+
+// |color|Hglyph:glyph_slot_id:glyph_prop_id|h[%s]|h|r
+// |cff66bbff|Hglyph:21:762|h[Glyph of Bladestorm]|h|r
+bool GlyphChatLink::Initialize(std::istringstream& iss)
+{
+    if (_color != CHAT_LINK_COLOR_GLYPH)
+        return false;
+    // Slot
+    if (!ReadUInt32(iss, _slotId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading slot id", iss.str().c_str());
+        return false;
+    }
+    // Check delimiter
+    if (!CheckDelimiter(iss, DELIMITER, "glyph"))
+        return false;
+    // Glyph Id
+    uint32 glyphId = 0;
+    if (!ReadUInt32(iss, glyphId))
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly while reading glyph entry", iss.str().c_str());
+        return false;
+    }
+    // Validate glyph
+    _glyph = sGlyphPropertiesStore.LookupEntry(glyphId);
+    if (!_glyph)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid glyph id %u in |glyph command", iss.str().c_str(), glyphId);
+        return false;
+    }
+    // Validate glyph's spell
+    _spell = sSpellStore.LookupEntry(_glyph->SpellId);
+    if (!_spell)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): got invalid spell id %u in |glyph command", iss.str().c_str(), _glyph->SpellId);
+        return false;
+    }
+    return true;
+}
+
+LinkExtractor::LinkExtractor(const char* msg) : _iss(msg) { }
+
+LinkExtractor::~LinkExtractor()
+{
+    for (Links::iterator itr = _links.begin(); itr != _links.end(); ++itr)
+        delete (*itr);
+    _links.clear();
+}
+
+bool LinkExtractor::IsValidMessage()
+{
+    const char validSequence[6] = "cHhhr";
+    const char* validSequenceIterator = validSequence;
+
+    char buffer[256];
+
+    std::istringstream::pos_type startPos = 0;
+    uint32 color = 0;
+
+    ChatLink* link = NULL;
+    while (!_iss.eof())
+    {
+        if (validSequence == validSequenceIterator)
+        {
+            if (link)
+            {
+                _links.push_back(link);
+                link = NULL;
+            }
+            _iss.ignore(255, PIPE_CHAR);
+            startPos = _iss.tellg() - std::istringstream::pos_type(1);
+        }
+        else if (_iss.get() != PIPE_CHAR)
+        {
+            LOG("ChatHandler::isValidChatMessage('%s'): sequence aborted unexpectedly", _iss.str().c_str());
+            return false;
+        }
+
+        // pipe has always to be followed by at least one char
+        if (_iss.peek() == '\0')
+        {
+            LOG("ChatHandler::isValidChatMessage('%s'): pipe followed by '\\0'", _iss.str().c_str());
+            return false;
+        }
+
+        // no further pipe commands
+        if (_iss.eof())
+            break;
+
+        char commandChar;
+        _iss >> commandChar;
+
+        // | in normal messages is escaped by ||
+        if (commandChar != PIPE_CHAR)
+        {
+            if (commandChar == *validSequenceIterator)
+            {
+                if (validSequenceIterator == validSequence+4)
+                    validSequenceIterator = validSequence;
+                else
+                    ++validSequenceIterator;
+            }
+            else
+            {
+                LOG("ChatHandler::isValidChatMessage('%s'): invalid sequence, expected '%c' but got '%c'", _iss.str().c_str(), *validSequenceIterator, commandChar);
+                return false;
+            }
+        }
+        else if (validSequence != validSequenceIterator)
+        {
+            // no escaped pipes in sequences
+            LOG("ChatHandler::isValidChatMessage('%s'): got escaped pipe in sequence", _iss.str().c_str());
+            return false;
+        }
+
+        switch (commandChar)
+        {
+            case 'c':
+                if (!ReadHex(_iss, color, 8))
+                {
+                    LOG("ChatHandler::isValidChatMessage('%s'): invalid hexadecimal number while reading color", _iss.str().c_str());
+                    return false;
+                }
+                break;
+            case 'H':
+                // read chars up to colon = link type
+                _iss.getline(buffer, 256, DELIMITER);
+                if (_iss.eof())
+                {
+                    LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly", _iss.str().c_str());
+                    return false;
+                }
+
+                if (strcmp(buffer, "item") == 0)
+                    link = new ItemChatLink();
+                else if (strcmp(buffer, "quest") == 0)
+                    link = new QuestChatLink();
+                else if (strcmp(buffer, "trade") == 0)
+                    link = new TradeChatLink();
+                else if (strcmp(buffer, "talent") == 0)
+                    link = new TalentChatLink();
+                else if (strcmp(buffer, "spell") == 0)
+                    link = new SpellChatLink();
+                else if (strcmp(buffer, "enchant") == 0)
+                    link = new EnchantmentChatLink();
+                else if (strcmp(buffer, "achievement") == 0)
+                    link = new AchievementChatLink();
+                else if (strcmp(buffer, "glyph") == 0)
+                    link = new GlyphChatLink();
+                else
+                {
+                    LOG("ChatHandler::isValidChatMessage('%s'): user sent unsupported link type '%s'", _iss.str().c_str(), buffer);
+                    return false;
+                }
+                link->SetColor(color);
+                if (!link->Initialize(_iss))
+                    return false;
+                break;
+            case 'h':
+                // if h is next element in sequence, this one must contain the linked text :)
+                if (*validSequenceIterator == 'h')
+                {
+                    // links start with '['
+                    if (_iss.get() != '[')
+                    {
+                        LOG("ChatHandler::isValidChatMessage('%s'): link caption doesn't start with '['", _iss.str().c_str());
+                        return false;
+                    }
+                    _iss.getline(buffer, 256, ']');
+                    if (_iss.eof())
+                    {
+                        LOG("ChatHandler::isValidChatMessage('%s'): sequence finished unexpectedly", _iss.str().c_str());
+                        return false;
+                    }
+
+                    if (!link)
+                        return false;
+
+                    if (!link->ValidateName(buffer, _iss.str().c_str()))
+                        return false;
+                }
+                break;
+            case 'r':
+                if (link)
+                    link->SetBounds(startPos, _iss.tellg());
+            case '|':
+                // no further payload
+                break;
+            default:
+                LOG("ChatHandler::isValidChatMessage('%s'): got invalid command |%c", _iss.str().c_str(), commandChar);
+                return false;
+        }
+    }
+
+    // check if every opened sequence was also closed properly
+    if (validSequence != validSequenceIterator)
+    {
+        LOG("ChatHandler::isValidChatMessage('%s'): EOF in active sequence", _iss.str().c_str());
+        return false;
+    }
+
+    return true;
+}