Only delete empty expeditions when the dz is empty

Zones are no longer able to delete expeditions. World now tracks empty expeditions in cache and only deletes them when it detects an expedition's dynamic zone instance has no more clients inside. This fixes an exploit where lockouts couldn't be applied to expeditions after all members were removed because zones were deleting the expedition immediately. Clients still inside the dz were able to complete events before being kicked from the instance while not having an expedition. Expeditions are no longer purged from database in the world purge instance timer to avoid a possible race with this new system
2026-09-03 13:36:36 +00:00 · 2020-05-26 22:32:08 -04:00
parent dcbcc5a156
commit 148af3edfc
10 changed files with 167 additions and 101 deletions
@@ -45,10 +45,10 @@ Expedition::Expedition(
 	m_expire_time = std::chrono::system_clock::from_time_t(m_start_time + m_duration);
 }

-void Expedition::SendZonesExpeditionExpired()
+void Expedition::SendZonesExpeditionDeleted()
 {
 	uint32_t pack_size = sizeof(ServerExpeditionID_Struct);
-	auto pack = std::unique_ptr<ServerPacket>(new ServerPacket(ServerOP_ExpeditionExpired, pack_size));
+	auto pack = std::unique_ptr<ServerPacket>(new ServerPacket(ServerOP_ExpeditionDeleted, pack_size));
 	auto buf = reinterpret_cast<ServerExpeditionID_Struct*>(pack->pBuffer);
 	buf->expedition_id = GetID();
 	zoneserver_list.SendPacket(pack.get());
@@ -95,6 +95,34 @@ void ExpeditionCache::RemoveExpedition(uint32_t expedition_id)
 	), m_expeditions.end());
 }

+void ExpeditionCache::MemberChange(uint32_t expedition_id, uint32_t character_id, bool remove)
+{
+	auto it = std::find_if(m_expeditions.begin(), m_expeditions.end(), [&](const Expedition& expedition) {
+		return expedition.GetID() == expedition_id;
+	});
+
+	if (it != m_expeditions.end())
+	{
+		if (remove) {
+			it->RemoveMember(character_id);
+		} else {
+			it->AddMember(character_id);
+		}
+	}
+}
+
+void ExpeditionCache::RemoveAllMembers(uint32_t expedition_id)
+{
+	auto it = std::find_if(m_expeditions.begin(), m_expeditions.end(), [&](const Expedition& expedition) {
+		return expedition.GetID() == expedition_id;
+	});
+
+	if (it != m_expeditions.end())
+	{
+		it->RemoveAllMembers();
+	}
+}
+
 void ExpeditionCache::Process()
 {
 	if (!m_process_throttle_timer.Check())
@@ -104,23 +132,28 @@ void ExpeditionCache::Process()

 	std::vector<uint32_t> expedition_ids;

-	// check for expired expeditions (using the dz instance expiration time)
+	// check cache for expired or empty expeditions to delete and notify zones.
 	for (auto it = m_expeditions.begin(); it != m_expeditions.end();)
 	{
-		if (!it->IsExpired())
+		bool is_deleted = false;
+
+		if (it->IsEmpty() || it->IsExpired())
 		{
-			++it;
-		}
-		else
-		{
-			// we need to delete expired expeditions from the database now instead
-			// of waiting for purge timer so members can request new expeditions.
-			// the dz should process this on its own to kick any clients inside it
-			LogExpeditions("Expedition [{}] expired, notifying zones and deleting", it->GetID());
-			expedition_ids.emplace_back(it->GetID());
-			it->SendZonesExpeditionExpired();
-			it = m_expeditions.erase(it);
+			// don't delete expedition until its dz instance is empty. this prevents
+			// an exploit where all members leave expedition and complete an event
+			// before being kicked from removal timer. the lockout could never be
+			// applied because the zone expedition cache was already invalidated.
+			auto dz_zoneserver = zoneserver_list.FindByInstanceID(it->GetInstanceID());
+			if (!dz_zoneserver || dz_zoneserver->NumPlayers() == 0)
+			{
+				LogExpeditions("Expedition [{}] expired or empty, notifying zones and deleting", it->GetID());
+				expedition_ids.emplace_back(it->GetID());
+				it->SendZonesExpeditionDeleted();
+				is_deleted = true;
+			}
 		}
+
+		it = is_deleted ? m_expeditions.erase(it) : it + 1;
 	}

 	if (!expedition_ids.empty())
@@ -177,9 +210,13 @@ std::vector<Expedition> ExpeditionDatabase::LoadExpeditions()
 			expedition_details.instance_id,
 			instance_list.zone,
 			instance_list.start_time,
-			instance_list.duration
+			instance_list.duration,
+			expedition_members.character_id
 		FROM expedition_details
 			INNER JOIN instance_list ON expedition_details.instance_id = instance_list.id
+			INNER JOIN expedition_members
+				ON expedition_members.expedition_id = expedition_details.id
+				AND expedition_members.is_current_member = TRUE
 		ORDER BY expedition_details.id;
 	);

@@ -190,15 +227,27 @@ std::vector<Expedition> ExpeditionDatabase::LoadExpeditions()
 	}
 	else
 	{
+		uint32_t last_expedition_id = 0;
+
 		for (auto row = results.begin(); row != results.end(); ++row)
 		{
-			expeditions.emplace_back(Expedition{
-				static_cast<uint32_t>(strtoul(row[0], nullptr, 10)), // expedition_id
-				static_cast<uint32_t>(strtoul(row[1], nullptr, 10)), // dz_instance_id
-				static_cast<uint32_t>(strtoul(row[2], nullptr, 10)), // dz_zone_id
-				static_cast<uint32_t>(strtoul(row[3], nullptr, 10)), // start_time
-				static_cast<uint32_t>(strtoul(row[4], nullptr, 10))  // duration
-			});
+			uint32_t expedition_id = strtoul(row[0], nullptr, 10);
+
+			if (last_expedition_id != expedition_id)
+			{
+				expeditions.emplace_back(Expedition{
+					static_cast<uint32_t>(strtoul(row[0], nullptr, 10)), // expedition_id
+					static_cast<uint32_t>(strtoul(row[1], nullptr, 10)), // dz_instance_id
+					static_cast<uint32_t>(strtoul(row[2], nullptr, 10)), // dz_zone_id
+					static_cast<uint32_t>(strtoul(row[3], nullptr, 10)), // start_time
+					static_cast<uint32_t>(strtoul(row[4], nullptr, 10))  // duration
+				});
+			}
+
+			last_expedition_id = expedition_id;
+
+			uint32_t member_id = static_cast<uint32_t>(strtoul(row[5], nullptr, 10));
+			expeditions.back().AddMember(member_id);
 		}
 	}

@@ -207,15 +256,21 @@ std::vector<Expedition> ExpeditionDatabase::LoadExpeditions()

 Expedition ExpeditionDatabase::LoadExpedition(uint32_t expedition_id)
 {
+	Expedition expedition;
+
 	std::string query = fmt::format(SQL(
 		SELECT
 			expedition_details.id,
 			expedition_details.instance_id,
 			instance_list.zone,
 			instance_list.start_time,
-			instance_list.duration
+			instance_list.duration,
+			expedition_members.character_id
 		FROM expedition_details
 			INNER JOIN instance_list ON expedition_details.instance_id = instance_list.id
+			INNER JOIN expedition_members
+				ON expedition_members.expedition_id = expedition_details.id
+				AND expedition_members.is_current_member = TRUE
 		WHERE expedition_details.id = {};
 	), expedition_id);

@@ -224,19 +279,29 @@ Expedition ExpeditionDatabase::LoadExpedition(uint32_t expedition_id)
 	{
 		LogExpeditions("Failed to load expedition [{}] for world cache", expedition_id);
 	}
-	else if (results.RowCount() > 0)
+	else
 	{
-		auto row = results.begin();
-		return Expedition{
-			static_cast<uint32_t>(strtoul(row[0], nullptr, 10)), // expedition_id
-			static_cast<uint32_t>(strtoul(row[1], nullptr, 10)), // dz_instance_id
-			static_cast<uint32_t>(strtoul(row[2], nullptr, 10)), // dz_zone_id
-			static_cast<uint32_t>(strtoul(row[3], nullptr, 10)), // start_time
-			static_cast<uint32_t>(strtoul(row[4], nullptr, 10))  // duration
-		};
+		bool created = false;
+		for (auto row = results.begin(); row != results.end(); ++row)
+		{
+			if (!created)
+			{
+				expedition = Expedition{
+					static_cast<uint32_t>(strtoul(row[0], nullptr, 10)), // expedition_id
+					static_cast<uint32_t>(strtoul(row[1], nullptr, 10)), // dz_instance_id
+					static_cast<uint32_t>(strtoul(row[2], nullptr, 10)), // dz_zone_id
+					static_cast<uint32_t>(strtoul(row[3], nullptr, 10)), // start_time
+					static_cast<uint32_t>(strtoul(row[4], nullptr, 10))  // duration
+				};
+				created = true;
+			}
+
+			auto member_id = static_cast<uint32_t>(strtoul(row[5], nullptr, 10));
+			expedition.AddMember(member_id);
+		}
 	}

-	return Expedition{};
+	return expedition;
 }

 void ExpeditionDatabase::DeleteExpeditions(const std::vector<uint32_t>& expedition_ids)
@@ -280,10 +345,25 @@ void ExpeditionMessage::HandleZoneMessage(ServerPacket* pack)
 		zoneserver_list.SendPacket(pack);
 		break;
 	}
-	case ServerOP_ExpeditionDeleted:
+	case ServerOP_ExpeditionMemberChange:
+	{
+		auto buf = reinterpret_cast<ServerExpeditionMemberChange_Struct*>(pack->pBuffer);
+		expedition_cache.MemberChange(buf->expedition_id, buf->char_id, buf->removed);
+		zoneserver_list.SendPacket(pack);
+		break;
+	}
+	case ServerOP_ExpeditionMemberSwap:
+	{
+		auto buf = reinterpret_cast<ServerExpeditionMemberSwap_Struct*>(pack->pBuffer);
+		expedition_cache.MemberChange(buf->expedition_id, buf->remove_char_id, true);
+		expedition_cache.MemberChange(buf->expedition_id, buf->add_char_id, false);
+		zoneserver_list.SendPacket(pack);
+		break;
+	}
+	case ServerOP_ExpeditionMembersRemoved:
 	{
 		auto buf = reinterpret_cast<ServerExpeditionID_Struct*>(pack->pBuffer);
-		expedition_cache.RemoveExpedition(buf->expedition_id);
+		expedition_cache.RemoveAllMembers(buf->expedition_id);
 		zoneserver_list.SendPacket(pack);
 		break;
 	}
@@ -24,6 +24,7 @@
 #include "../common/rulesys.h"
 #include "../common/timer.h"
 #include <chrono>
+#include <unordered_set>
 #include <vector>

 extern class ExpeditionCache expedition_cache;
@@ -56,6 +57,8 @@ public:
 	void AddExpedition(uint32_t expedition_id);
 	void RemoveExpedition(uint32_t expedition_id);
 	void LoadActiveExpeditions();
+	void MemberChange(uint32_t expedition_id, uint32_t character_id, bool remove);
+	void RemoveAllMembers(uint32_t expedition_id);
 	void Process();

 private:
@@ -71,9 +74,15 @@ public:
 		uint32_t expedition_id, uint32_t instance_id, uint32_t dz_zone_id,
 		uint32_t expire_time, uint32_t duration);

+	void AddMember(uint32_t character_id) { m_member_ids.emplace(character_id); }
+	void RemoveMember(uint32_t character_id) { m_member_ids.erase(character_id); }
+	void RemoveAllMembers() { m_member_ids.clear(); }
 	uint32_t GetID() const { return m_expedition_id; }
+	uint16_t GetInstanceID() const { return static_cast<uint16_t>(m_dz_instance_id); }
+	uint16_t GetZoneID() const { return static_cast<uint16_t>(m_dz_zone_id); }
+	bool IsEmpty() const { return m_member_ids.empty(); }
 	bool IsExpired() const { return m_expire_time < std::chrono::system_clock::now(); }
-	void SendZonesExpeditionExpired();
+	void SendZonesExpeditionDeleted();

 private:
 	uint32_t m_expedition_id  = 0;
@@ -81,6 +90,7 @@ private:
 	uint32_t m_dz_zone_id     = 0;
 	uint32_t m_start_time     = 0;
 	uint32_t m_duration       = 0;
+	std::unordered_set<uint32_t> m_member_ids;
 	std::chrono::time_point<std::chrono::system_clock> m_expire_time;
 };

@@ -607,7 +607,6 @@ int main(int argc, char** argv) {
 		if (PurgeInstanceTimer.Check()) {
 			database.PurgeExpiredInstances();
 			database.PurgeAllDeletedDataBuckets();
-			ExpeditionDatabase::PurgeExpiredExpeditions();
 			ExpeditionDatabase::PurgeExpiredCharacterLockouts();
 		}

@@ -1371,8 +1371,6 @@ void ZoneServer::HandleMessage(uint16 opcode, const EQ::Net::Packet &p) {
 	case ServerOP_ExpeditionLeaderChanged:
 	case ServerOP_ExpeditionLockout:
 	case ServerOP_ExpeditionLockState:
-	case ServerOP_ExpeditionMemberChange:
-	case ServerOP_ExpeditionMemberSwap:
 	case ServerOP_ExpeditionMemberStatus:
 	case ServerOP_ExpeditionReplayOnJoin:
 	case ServerOP_ExpeditionDzCompass:
@@ -1383,8 +1381,10 @@ void ZoneServer::HandleMessage(uint16 opcode, const EQ::Net::Packet &p) {
 		break;
 	}
 	case ServerOP_ExpeditionCreate:
-	case ServerOP_ExpeditionDeleted:
 	case ServerOP_ExpeditionGetOnlineMembers:
+	case ServerOP_ExpeditionMemberChange:
+	case ServerOP_ExpeditionMemberSwap:
+	case ServerOP_ExpeditionMembersRemoved:
 	case ServerOP_ExpeditionDzAddPlayer:
 	case ServerOP_ExpeditionDzMakeLeader:
 	case ServerOP_ExpeditionRemoveCharLockouts: