/*
* Copyright (c) 2013-2026, The PurpleI2P Project
*
* This file is part of Purple i2pd project and licensed under BSD3
*
* See full license text in LICENSE file at top of project tree
*/

#include <algorithm>
#include <cassert>
#include <string>
#include <set>
#include <vector>
#include <charconv>
#include <future>
#include <boost/algorithm/string.hpp>
#include "Crypto.h"
#include "ECIESX25519AEADRatchetSession.h"
#include "Log.h"
#include "FS.h"
#include "Timestamp.h"
#include "NetDb.hpp"
#include "Destination.h"

namespace i2p
{
namespace client
{
	LeaseSetDestination::LeaseSetDestination (boost::asio::io_context& service,
		bool isPublic, const i2p::util::Mapping * params):
		m_Service (service), m_IsPublic (isPublic), m_PublishReplyToken (0),
		m_LastSubmissionTime (0), m_PublishConfirmationTimer (m_Service),
		m_PublishVerificationTimer (m_Service), m_PublishDelayTimer (m_Service), m_CleanupTimer (m_Service),
		m_LeaseSetType (DEFAULT_LEASESET_TYPE), m_AuthType (i2p::data::ENCRYPTED_LEASESET_AUTH_TYPE_NONE)
	{
		int inLen   = DEFAULT_INBOUND_TUNNEL_LENGTH;
		int inQty   = DEFAULT_INBOUND_TUNNELS_QUANTITY;
		int outLen  = DEFAULT_OUTBOUND_TUNNEL_LENGTH;
		int outQty  = DEFAULT_OUTBOUND_TUNNELS_QUANTITY;
		int inVar   = DEFAULT_INBOUND_TUNNELS_LENGTH_VARIANCE;
		int outVar  = DEFAULT_OUTBOUND_TUNNELS_LENGTH_VARIANCE;
		int numTags = DEFAULT_TAGS_TO_SEND;
		bool isHighBandwidth = true;
		std::shared_ptr<std::vector<i2p::data::IdentHash> > explicitPeers;
		std::string_view explicitPeersStr, trustedRoutersStr, inboundRandomKeyStr, outboundRandomKeyStr;
		try
		{
			if (params)
			{
				params->Get (I2CP_PARAM_INBOUND_TUNNEL_LENGTH, inLen);
				params->Get (I2CP_PARAM_OUTBOUND_TUNNEL_LENGTH, outLen);
				params->Get (I2CP_PARAM_INBOUND_TUNNELS_QUANTITY, inQty);
				params->Get (I2CP_PARAM_OUTBOUND_TUNNELS_QUANTITY, outQty);
				params->Get (I2CP_PARAM_INBOUND_TUNNELS_LENGTH_VARIANCE, inVar);
				params->Get (I2CP_PARAM_OUTBOUND_TUNNELS_LENGTH_VARIANCE, outVar);
				params->Get (I2CP_PARAM_TAGS_TO_SEND, numTags);
				LogPrint (eLogInfo, "Destination: Parameters for tunnel set to: ", inQty, " inbound (", inLen, " hops), ", outQty, " outbound (", outLen, " hops), ", numTags, " tags");
				int ratchetsInboundTags = 0;
				if (params->Get (I2CP_PARAM_RATCHET_INBOUND_TAGS, ratchetsInboundTags))
				{
					if (ratchetsInboundTags && ratchetsInboundTags < i2p::garlic::ECIESX25519_MIN_NUM_GENERATED_TAGS)
						ratchetsInboundTags = i2p::garlic::ECIESX25519_MIN_NUM_GENERATED_TAGS;
					SetNumRatchetInboundTags (ratchetsInboundTags);
				}
				explicitPeersStr = (*params)[I2CP_PARAM_EXPLICIT_PEERS];
				trustedRoutersStr = (*params)[I2CP_PARAM_TRUSTED_ROUTERS];
				inboundRandomKeyStr = (*params)[I2CP_PARAM_INBOUND_RANDOM_KEY];
				outboundRandomKeyStr = (*params)[I2CP_PARAM_OUTBOUND_RANDOM_KEY];
				m_Nickname = (*params)[I2CP_PARAM_INBOUND_NICKNAME];
				if (m_Nickname.empty ()) // try outbound
					m_Nickname = (*params)[I2CP_PARAM_OUTBOUND_NICKNAME];
				// otherwise we set default nickname in Start when we know local address
				bool dontPublishLeaseSet = true;
				if (params->Get (I2CP_PARAM_DONT_PUBLISH_LEASESET, dontPublishLeaseSet))
					m_IsPublic = !dontPublishLeaseSet; // override isPublic
				params->Get (I2CP_PARAM_LEASESET_TYPE, m_LeaseSetType);
				if (m_LeaseSetType == i2p::data::NETDB_STORE_TYPE_ENCRYPTED_LEASESET2)
				{
					// authentication for encrypted LeaseSet
					int authType = 0;
					if (params->Get (I2CP_PARAM_LEASESET_AUTH_TYPE, authType))
					{
						if (authType >= i2p::data::ENCRYPTED_LEASESET_AUTH_TYPE_NONE && authType <= i2p::data::ENCRYPTED_LEASESET_AUTH_TYPE_PSK)
							m_AuthType = authType;
						else
							LogPrint (eLogError, "Destination: Unknown auth type: ", authType);
					}
				}
				auto leaseSetPrivKey = (*params)[I2CP_PARAM_LEASESET_PRIV_KEY];
				if (!leaseSetPrivKey.empty ())
				{
					m_LeaseSetPrivKey.reset (new i2p::data::Tag<32>());
					if (m_LeaseSetPrivKey->FromBase64 (leaseSetPrivKey) != 32)
					{
						LogPrint(eLogCritical, "Destination: Invalid value i2cp.leaseSetPrivKey: ", leaseSetPrivKey);
						m_LeaseSetPrivKey.reset (nullptr);
					}
				}
				int streamingProfile = 0;
				if (params->Get (I2CP_PARAM_STREAMING_PROFILE, streamingProfile))
					isHighBandwidth = streamingProfile != STREAMING_PROFILE_INTERACTIVE;
			}
		}
		catch (std::exception & ex)
		{
			LogPrint(eLogError, "Destination: Unable to parse parameters for destination: ", ex.what());
		}
		SetNumTags (numTags);
		m_Pool = i2p::tunnel::tunnels.CreateTunnelPool (inLen, outLen, inQty, outQty, inVar, outVar, isHighBandwidth);
		if (!explicitPeersStr.empty ())
			m_Pool->SetExplicitPeers (i2p::data::ExtractIdentHashes (explicitPeersStr));
		if (!trustedRoutersStr.empty ())
			m_Pool->SetTrustedRouters (i2p::data::ExtractIdentHashes (trustedRoutersStr));
		if (!inboundRandomKeyStr.empty ())
		{
			uint8_t key[32]; // might be 32 bytes, but only first 16 bytes are used
			if (i2p::data::Base64ToByteStream (inboundRandomKeyStr, key, 32) >= 16)
				m_Pool->SetInboundPeerOrderingKey (key);
		}
		if (!outboundRandomKeyStr.empty ())
		{
			uint8_t key[32]; // might be 32 bytes, but only first 16 bytes are used
			if (i2p::data::Base64ToByteStream (outboundRandomKeyStr, key, 32) >= 16)
				m_Pool->SetOutboundPeerOrderingKey (key);
		}
		if(params)
		{
			int maxLatency = 0;
			if (params->Get (I2CP_PARAM_MAX_TUNNEL_LATENCY, maxLatency))
			{
				int minLatency = 0;
				if (params->Get (I2CP_PARAM_MIN_TUNNEL_LATENCY, minLatency))
				{
					if (minLatency > 0 && maxLatency > 0)
					{
						// set tunnel pool latency
						LogPrint(eLogInfo, "Destination: Requiring tunnel latency [", minLatency, "ms, ", maxLatency, "ms]");
						m_Pool->RequireLatency(minLatency, maxLatency);
					}
				}
			}
		}
	}

	LeaseSetDestination::~LeaseSetDestination ()
	{
		if (m_Pool)
			i2p::tunnel::tunnels.DeleteTunnelPool (m_Pool);
		for (auto& it: m_LeaseSetRequests)
			it.second->Complete (nullptr);
	}

	void LeaseSetDestination::Start ()
	{
		if (m_Nickname.empty ())
			m_Nickname = i2p::data::GetIdentHashAbbreviation (GetIdentHash ()); // set default nickname
		LoadTags ();
		m_Pool->SetLocalDestination (shared_from_this ());
		m_Pool->SetActive (true);
		m_CleanupTimer.expires_after (std::chrono::seconds (DESTINATION_CLEANUP_TIMEOUT));
		m_CleanupTimer.async_wait (std::bind (&LeaseSetDestination::HandleCleanupTimer,
			shared_from_this (), std::placeholders::_1));
	}

	void LeaseSetDestination::Stop ()
	{
		m_CleanupTimer.cancel ();
		m_PublishConfirmationTimer.cancel ();
		m_PublishVerificationTimer.cancel ();
		m_PublishDelayTimer.cancel ();
		if (m_Pool)
		{
			m_Pool->SetLocalDestination (nullptr);
			i2p::tunnel::tunnels.StopTunnelPool (m_Pool);
		}
		SaveTags ();
		CleanUp (); // GarlicDestination
	}


	bool LeaseSetDestination::Reconfigure (const i2p::util::Mapping& params)
	{
		bool dontPublishLeaseSet = !m_IsPublic;
		params.Get(I2CP_PARAM_DONT_PUBLISH_LEASESET, dontPublishLeaseSet);
		m_IsPublic = !dontPublishLeaseSet;
		auto numTags = GetNumTags ();
		params.Get (I2CP_PARAM_TAGS_TO_SEND, numTags);
		auto numRatchetInboundTags = GetNumRatchetInboundTags ();
		params.Get (I2CP_PARAM_RATCHET_INBOUND_TAGS, numRatchetInboundTags);
		auto pool = GetTunnelPool();
		auto inLen = pool->GetNumInboundHops();
		params.Get (I2CP_PARAM_INBOUND_TUNNEL_LENGTH, inLen);
		auto outLen = pool->GetNumOutboundHops();
		params.Get (I2CP_PARAM_OUTBOUND_TUNNEL_LENGTH, outLen);
		auto inQuant = pool->GetNumInboundTunnels();
		params.Get (I2CP_PARAM_INBOUND_TUNNELS_QUANTITY, inQuant);
		auto outQuant = pool->GetNumOutboundTunnels();
		params.Get (I2CP_PARAM_OUTBOUND_TUNNELS_QUANTITY, outQuant);
		int minLatency = 0;
		params.Get (I2CP_PARAM_MIN_TUNNEL_LATENCY, minLatency);
		int maxLatency = 0;
		params.Get (I2CP_PARAM_MAX_TUNNEL_LATENCY, maxLatency);

		SetNumTags (numTags);
		SetNumRatchetInboundTags (numRatchetInboundTags);
		pool->RequireLatency(minLatency, maxLatency);
		return pool->Reconfigure(inLen, outLen, inQuant, outQuant);
	}

	std::shared_ptr<i2p::data::LeaseSet> LeaseSetDestination::FindLeaseSet (const i2p::data::IdentHash& ident)
	{
		std::shared_ptr<i2p::data::LeaseSet> remoteLS;
		{
			std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
			auto it = m_RemoteLeaseSets.find (ident);
			if (it != m_RemoteLeaseSets.end ())
				remoteLS = it->second;
		}

		if (remoteLS)
		{
			if (!remoteLS->IsExpired ())
			{
				if (remoteLS->ExpiresSoon())
				{
					LogPrint(eLogDebug, "Destination: Lease Set expires soon, updating before expire");
					// update now before expiration for smooth handover
					auto s = shared_from_this ();
					RequestDestination(ident, [s, ident] (std::shared_ptr<i2p::data::LeaseSet> ls) {
						if(ls && !ls->IsExpired())
						{
							ls->PopulateLeases();
							{
								std::lock_guard<std::mutex> _lock(s->m_RemoteLeaseSetsMutex);
								s->m_RemoteLeaseSets[ident] = ls;
							}
						}
					});
				}
				return remoteLS;
			}
			else
			{
				LogPrint (eLogWarning, "Destination: Remote LeaseSet expired");
				std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
				m_RemoteLeaseSets.erase (ident);
				return nullptr;
			}
		}
		return nullptr;
	}

	std::shared_ptr<const i2p::data::LocalLeaseSet> LeaseSetDestination::GetLeaseSet ()
	{
		if (!m_Pool) return nullptr;
		if (!m_LeaseSet)
			UpdateLeaseSet ();
		auto ls = GetLeaseSetMt ();
		return (ls && ls->GetInnerLeaseSet ()) ? ls->GetInnerLeaseSet () : ls; // always non-encrypted
	}

	std::shared_ptr<const i2p::data::LocalLeaseSet> LeaseSetDestination::GetLeaseSetMt ()
	{
		std::lock_guard<std::mutex> l(m_LeaseSetMutex);
		return m_LeaseSet;
	}

	void LeaseSetDestination::SetLeaseSet (std::shared_ptr<const i2p::data::LocalLeaseSet> newLeaseSet)
	{
		{
			std::lock_guard<std::mutex> l(m_LeaseSetMutex);
			m_LeaseSet = newLeaseSet;
		}
		i2p::garlic::GarlicDestination::SetLeaseSetUpdated ();
		if (m_IsPublic)
		{
			auto s = shared_from_this ();
			boost::asio::post (m_Service, [s](void)
			{
				s->m_PublishVerificationTimer.cancel ();
				s->Publish ();
			});
		}
	}

	void LeaseSetDestination::UpdateLeaseSet ()
	{
		int numTunnels = m_Pool->GetNumInboundTunnels () + 2; // 2 backup tunnels
		if (numTunnels > i2p::data::MAX_NUM_LEASES) numTunnels = i2p::data::MAX_NUM_LEASES; // 16 tunnels maximum
		auto tunnels = m_Pool->GetInboundTunnels (numTunnels);
		if (!tunnels.empty ())
			CreateNewLeaseSet (tunnels);
		else
			LogPrint (eLogInfo, "Destination: No inbound tunnels for LeaseSet");
	}

	bool LeaseSetDestination::SubmitSessionKey (const uint8_t * key, const uint8_t * tag)
	{
		struct
		{
			uint8_t k[32], t[32];
		} data;
		memcpy (data.k, key, 32);
		memcpy (data.t, tag, 32);
		auto s = shared_from_this ();
		boost::asio::post (m_Service, [s,data](void)
			{
				s->AddSessionKey (data.k, data.t);
			});
		return true;
	}

	void LeaseSetDestination::SubmitECIESx25519Key (const uint8_t * key, uint64_t tag)
	{
		struct
		{
			uint8_t k[32];
			uint64_t t;
		} data;
		memcpy (data.k, key, 32);
		data.t = tag;
		auto s = shared_from_this ();
		boost::asio::post (m_Service, [s,data](void)
			{
				s->AddECIESx25519Key (data.k, data.t);
			});
	}

	void LeaseSetDestination::ProcessGarlicMessage (std::shared_ptr<I2NPMessage> msg)
	{
		if (!msg) return;
		bool empty = false;
		{
			std::lock_guard<std::mutex> l(m_IncomingMsgsQueueMutex);
			empty = m_IncomingMsgsQueue.empty ();
			m_IncomingMsgsQueue.push_back (msg);
		}
		if (empty)
			boost::asio::post (m_Service, [s = shared_from_this ()]()
			{
				std::list<std::shared_ptr<I2NPMessage> > receivedMsgs;
				{
					std::lock_guard<std::mutex> l(s->m_IncomingMsgsQueueMutex);
					s->m_IncomingMsgsQueue.swap (receivedMsgs);
				}
			    for (auto& it: receivedMsgs)
			    	s->HandleGarlicMessage (it);
			});
	}

	void LeaseSetDestination::ProcessDeliveryStatusMessage (std::shared_ptr<I2NPMessage> msg)
	{
		uint32_t msgID = bufbe32toh (msg->GetPayload () + DELIVERY_STATUS_MSGID_OFFSET);
		boost::asio::post (m_Service, std::bind (&LeaseSetDestination::HandleDeliveryStatusMessage, shared_from_this (), msgID));
	}

	void LeaseSetDestination::HandleI2NPMessage (const uint8_t * buf, size_t len)
	{
		if (len < I2NP_HEADER_SIZE)
		{
			LogPrint (eLogWarning, "Destination: I2NP message is too short ", len);
			return;
		}
		I2NPMessageType typeID = (I2NPMessageType)(buf[I2NP_HEADER_TYPEID_OFFSET]);
		uint32_t msgID = bufbe32toh (buf + I2NP_HEADER_MSGID_OFFSET);
		LeaseSetDestination::HandleCloveI2NPMessage (typeID, buf + I2NP_HEADER_SIZE,
			GetI2NPMessageLength(buf, len) - I2NP_HEADER_SIZE, msgID, nullptr);
	}

	bool LeaseSetDestination::HandleCloveI2NPMessage (I2NPMessageType typeID, const uint8_t * payload,
		size_t len, uint32_t msgID, i2p::garlic::ECIESX25519AEADRatchetSession * from)
	{
		switch (typeID)
		{
			case eI2NPData:
				HandleDataMessage (payload, len, from);
			break;
			case eI2NPDeliveryStatus:
				HandleDeliveryStatusMessage (bufbe32toh (payload + DELIVERY_STATUS_MSGID_OFFSET));
			break;
			case eI2NPTunnelTest:
				if (m_Pool)
					m_Pool->ProcessTunnelTest (bufbe32toh (payload + TUNNEL_TEST_MSGID_OFFSET), bufbe64toh (payload + TUNNEL_TEST_TIMESTAMP_OFFSET));
			break;
			case eI2NPDatabaseStore:
				HandleDatabaseStoreMessage (payload, len, from);
			break;
			case eI2NPDatabaseSearchReply:
				HandleDatabaseSearchReplyMessage (payload, len);
			break;
			case eI2NPShortTunnelBuildReply: // might come as garlic encrypted
				i2p::HandleI2NPMessage (CreateI2NPMessage (typeID, payload, len, msgID));
			break;
			default:
				LogPrint (eLogWarning, "Destination: Unexpected I2NP message type ", typeID);
				return false;
		}
		return true;
	}

	void LeaseSetDestination::HandleDatabaseStoreMessage (const uint8_t * buf, size_t len,
		i2p::garlic::ECIESX25519AEADRatchetSession * from)
	{
		if (len < DATABASE_STORE_HEADER_SIZE)
		{
			LogPrint (eLogError, "Destination: Database store msg is too short ", len);
			return;
		}
		uint32_t replyToken = bufbe32toh (buf + DATABASE_STORE_REPLY_TOKEN_OFFSET);
		size_t offset = DATABASE_STORE_HEADER_SIZE;
		if (replyToken)
		{
			LogPrint (eLogInfo, "Destination: Reply token is ignored for DatabaseStore");
			offset += 36;
		}
		if (offset > len || len > i2p::data::MAX_LS_BUFFER_SIZE + offset)
		{
			LogPrint (eLogError, "Destination: Database store message is too long ", len);
			return;
		}
		i2p::data::IdentHash key (buf + DATABASE_STORE_KEY_OFFSET);
		std::shared_ptr<i2p::data::LeaseSet> leaseSet;
		std::shared_ptr<LeaseSetRequest> request;
		switch (buf[DATABASE_STORE_TYPE_OFFSET])
		{
			case i2p::data::NETDB_STORE_TYPE_LEASESET: // 1
			case i2p::data::NETDB_STORE_TYPE_STANDARD_LEASESET2: // 3
			{
				LogPrint (eLogDebug, "Destination: Remote LeaseSet");
				std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
				auto it = m_RemoteLeaseSets.find (key);
				if (it != m_RemoteLeaseSets.end () &&
					it->second->GetStoreType () == buf[DATABASE_STORE_TYPE_OFFSET]) // update only if same type
				{
					leaseSet = it->second;
					if (leaseSet->IsNewer (buf + offset, len - offset))
					{
						leaseSet->Update (buf + offset, len - offset, shared_from_this(), true);
						if (leaseSet->IsValid () && leaseSet->GetIdentHash () == key && !leaseSet->IsExpired ())
							LogPrint (eLogDebug, "Destination: Remote LeaseSet updated");
						else
						{
							LogPrint (eLogDebug, "Destination: Remote LeaseSet update failed");
							m_RemoteLeaseSets.erase (it);
							leaseSet = nullptr;
						}
					}
					else
						LogPrint (eLogDebug, "Destination: Remote LeaseSet is older. Not updated");
				}
				else
				{
					// add or replace
					if (buf[DATABASE_STORE_TYPE_OFFSET] == i2p::data::NETDB_STORE_TYPE_LEASESET)
					{
						leaseSet = std::make_shared<i2p::data::LeaseSet> (buf + offset, len - offset); // LeaseSet
						if (!SupportsEncryptionType (i2p::data::CRYPTO_KEY_TYPE_ELGAMAL))
							leaseSet->SetIsIncompatibleCrypto (true);
					}
					else
					{
						leaseSet = std::make_shared<i2p::data::LeaseSet2> (buf[DATABASE_STORE_TYPE_OFFSET],
							buf + offset, len - offset, true, shared_from_this (),
						    from ? from->GetRemoteStaticKeyType () : GetPreferredCryptoType () ); // LeaseSet2
						if (from)
						{
							uint8_t pub[32];
							leaseSet->Encrypt (nullptr, pub);
							if (!memcmp (from->GetRemoteStaticKey (), pub, 32))
								from->SetDestination (leaseSet->GetIdentHash ());
							else
							{
								LogPrint (eLogError, "Destination: Remote LeaseSet static key mismatch");
								leaseSet = nullptr;
							}
						}
					}
					if (leaseSet && leaseSet->IsValid () && leaseSet->GetIdentHash () == key && !leaseSet->IsExpired ())
					{
						if (leaseSet->GetIdentHash () != GetIdentHash ())
						{
							LogPrint (eLogDebug, "Destination: New remote LeaseSet added");
							m_RemoteLeaseSets.insert_or_assign (key, leaseSet);
							if (from)
								from->SetDestination (key);
						}
						else
							LogPrint (eLogDebug, "Destination: Own remote LeaseSet dropped");
					}
					else
					{
						LogPrint (eLogError, "Destination: New remote LeaseSet failed");
						leaseSet = nullptr;
					}
				}
				break;
			}
			case i2p::data::NETDB_STORE_TYPE_ENCRYPTED_LEASESET2: // 5
			{
				auto it2 = m_LeaseSetRequests.find (key);
				if (it2 != m_LeaseSetRequests.end ())
				{
					request = it2->second;
					m_LeaseSetRequests.erase (it2);
					if (request->requestedBlindedKey)
					{
						auto ls2 = std::make_shared<i2p::data::LeaseSet2> (buf + offset, len - offset,
							request->requestedBlindedKey, shared_from_this (),
						    m_LeaseSetPrivKey ? ((const uint8_t *)*m_LeaseSetPrivKey) : nullptr, GetPreferredCryptoType ());
						if (ls2->IsValid () && !ls2->IsExpired ())
						{
							leaseSet = ls2;
							std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
							m_RemoteLeaseSets[ls2->GetIdentHash ()] = ls2; // ident is not key
							m_RemoteLeaseSets[key] = ls2; // also store as key for next lookup
						}
						else
							LogPrint (eLogError, "Destination: New remote encrypted LeaseSet2 failed");
					}
					else
					{
						// publishing verification doesn't have requestedBlindedKey
						auto localLeaseSet = GetLeaseSetMt ();
						if (localLeaseSet->GetStoreHash () == key)
						{
							auto ls = std::make_shared<i2p::data::LeaseSet2> (i2p::data::NETDB_STORE_TYPE_ENCRYPTED_LEASESET2,
								localLeaseSet->GetBuffer (), localLeaseSet->GetBufferLen (), false);
							leaseSet = ls;
						}
						else
							LogPrint (eLogWarning, "Destination: Encrypted LeaseSet2 received for request without blinded key");
					}
				}
				else
					LogPrint (eLogWarning, "Destination: Couldn't find request for encrypted LeaseSet2");
				break;
			}
			default:
				LogPrint (eLogError, "Destination: Unexpected client's DatabaseStore type ", buf[DATABASE_STORE_TYPE_OFFSET], ", dropped");
		}

		if (!request)
		{
			auto it1 = m_LeaseSetRequests.find (key);
			if (it1 != m_LeaseSetRequests.end ())
			{
				request = it1->second;
				m_LeaseSetRequests.erase (it1);
			}
		}
		if (request)
		{
			request->requestTimeoutTimer.cancel ();
			request->Complete (leaseSet);
		}
	}

	void LeaseSetDestination::HandleDatabaseSearchReplyMessage (const uint8_t * buf, size_t len)
	{
		if (len < 33)
		{
			LogPrint (eLogWarning, "Destination: Database search reply is too short, ", len);
			return;
		}
		i2p::data::IdentHash key (buf);
		int num = buf[32]; // num
		size_t maxNum = (len - 33)/32;
		if ((size_t)num > maxNum)
		{
			LogPrint (eLogWarning, "Destination: Declared number of peer hashes ", num, " exceeds message size, reduced to ", maxNum);
			num = maxNum;
		}
		LogPrint (eLogDebug, "Destination: DatabaseSearchReply for ", key.ToBase64 (), " num=", num);
		auto it = m_LeaseSetRequests.find (key);
		if (it != m_LeaseSetRequests.end ())
		{
			auto request = it->second;
			for (int i = 0; i < num; i++)
			{
				i2p::data::IdentHash peerHash (buf + 33 + i*32);
				if (!request->excluded.count (peerHash) && !i2p::data::netdb.FindRouter (peerHash))
				{
					LogPrint (eLogInfo, "Destination: Found new floodfill, request it");
					i2p::data::netdb.RequestDestination (peerHash, nullptr, false); // through exploratory
				}
			}
			SendNextLeaseSetRequest (key, request);
		}
		else
			LogPrint (eLogWarning, "Destination: Request for ", key.ToBase64 (), " not found");
	}

	void LeaseSetDestination::SendNextLeaseSetRequest (const i2p::data::IdentHash& key,
		std::shared_ptr<LeaseSetRequest> request)
	{
		bool found = false;
		if (request->excluded.size () < MAX_NUM_FLOODFILLS_PER_REQUEST)
		{
			auto floodfill = i2p::data::netdb.GetClosestFloodfill (key, request->excluded);
			if (floodfill)
			{
				LogPrint (eLogInfo, "Destination: Requesting ", key.ToBase64 (), " at ", floodfill->GetIdentHash ().ToBase64 ());
				if (SendLeaseSetRequest (key, floodfill, request))
					found = true;
			}
		}
		if (!found)
		{
			LogPrint (eLogInfo, "Destination: ", key.ToBase64 (), " was not found on ", MAX_NUM_FLOODFILLS_PER_REQUEST, " floodfills");
			request->Complete (nullptr);
			m_LeaseSetRequests.erase (key);
		}
	}

	void LeaseSetDestination::HandleDeliveryStatusMessage (uint32_t msgID)
	{
		if (msgID == m_PublishReplyToken)
		{
			LogPrint (eLogDebug, "Destination: Publishing LeaseSet confirmed for ", GetIdentHash().ToBase32());
			m_ExcludedFloodfills.clear ();
			m_PublishReplyToken = 0;
			// schedule verification
			m_PublishVerificationTimer.expires_after (std::chrono::seconds(PUBLISH_VERIFICATION_TIMEOUT +
				GetRng ()() % PUBLISH_VERIFICATION_TIMEOUT_VARIANCE));
			m_PublishVerificationTimer.async_wait (std::bind (&LeaseSetDestination::HandlePublishVerificationTimer,
			shared_from_this (), std::placeholders::_1));
		}
		else
			i2p::garlic::GarlicDestination::HandleDeliveryStatusMessage (msgID);
	}

	void LeaseSetDestination::SetLeaseSetUpdated (bool post)
	{
		if (post)
			boost::asio::post (m_Service, [s = shared_from_this ()]() { s->UpdateLeaseSet (); });
		else
			UpdateLeaseSet ();
	}

	void LeaseSetDestination::Publish ()
	{
		auto leaseSet = GetLeaseSetMt ();
		if (!leaseSet || !m_Pool)
		{
			LogPrint (eLogError, "Destination: Can't publish non-existing LeaseSet");
			return;
		}
		if (m_PublishReplyToken)
		{
			LogPrint (eLogDebug, "Destination: Publishing LeaseSet is pending");
			return;
		}
		auto ts = i2p::util::GetSecondsSinceEpoch ();
		if (ts < m_LastSubmissionTime + PUBLISH_MIN_INTERVAL)
		{
			LogPrint (eLogDebug, "Destination: Publishing LeaseSet is too fast. Wait for ", PUBLISH_MIN_INTERVAL, " seconds");
			m_PublishDelayTimer.cancel ();
			m_PublishDelayTimer.expires_after (std::chrono::seconds(PUBLISH_MIN_INTERVAL));
			m_PublishDelayTimer.async_wait (std::bind (&LeaseSetDestination::HandlePublishDelayTimer,
				shared_from_this (), std::placeholders::_1));
			return;
		}
		auto floodfill = i2p::data::netdb.GetClosestFloodfill (leaseSet->GetStoreHash (), m_ExcludedFloodfills);
		if (!floodfill)
		{
			LogPrint (eLogError, "Destination: Can't publish LeaseSet, no more floodfills found");
			m_ExcludedFloodfills.clear ();
			return;
		}
		auto outbound = m_Pool->GetNextOutboundTunnel (nullptr, floodfill->GetCompatibleTransports (false));
		auto inbound = m_Pool->GetNextInboundTunnel (nullptr, floodfill->GetCompatibleTransports (true));
		if (!outbound || !inbound)
		{
			if (m_Pool->HasInboundTunnels () && m_Pool->HasOutboundTunnels ())
			{
				LogPrint (eLogInfo, "Destination: No compatible tunnels with ", floodfill->GetIdentHash ().ToBase64 (), ". Trying another floodfill");
				m_ExcludedFloodfills.insert (floodfill->GetIdentHash ());
				floodfill = i2p::data::netdb.GetClosestFloodfill (leaseSet->GetStoreHash (), m_ExcludedFloodfills);
				if (floodfill)
				{
					outbound = m_Pool->GetNextOutboundTunnel (nullptr, floodfill->GetCompatibleTransports (false));
					if (outbound)
					{
						inbound = m_Pool->GetNextInboundTunnel (nullptr, floodfill->GetCompatibleTransports (true));
						if (!inbound)
							LogPrint (eLogError, "Destination: Can't publish LeaseSet. No inbound tunnels");
					}
					else
						LogPrint (eLogError, "Destination: Can't publish LeaseSet. No outbound tunnels");
				}
				else
					LogPrint (eLogError, "Destination: Can't publish LeaseSet, no more floodfills found");
			}
			else
				LogPrint (eLogDebug, "Destination: No tunnels in pool");

			if (!floodfill || !outbound || !inbound)
			{
				// we can't publish now
				m_ExcludedFloodfills.clear ();
				m_PublishReplyToken = 1; // dummy non-zero value
				// try again after a while
				LogPrint (eLogInfo, "Destination: Can't publish LeaseSet because destination is not ready. Try publishing again after ", PUBLISH_CONFIRMATION_TIMEOUT, " milliseconds");
				m_PublishConfirmationTimer.expires_after (std::chrono::milliseconds(PUBLISH_CONFIRMATION_TIMEOUT));
				m_PublishConfirmationTimer.async_wait (std::bind (&LeaseSetDestination::HandlePublishConfirmationTimer,
					shared_from_this (), std::placeholders::_1, PUBLISH_CONFIRMATION_TIMEOUT));
				return;
			}
		}
		m_ExcludedFloodfills.insert (floodfill->GetIdentHash ());
		LogPrint (eLogDebug, "Destination: Publish LeaseSet of ", GetIdentHash ().ToBase32 ());
		RAND_bytes ((uint8_t *)&m_PublishReplyToken, 4);
		auto msg = WrapMessageForRouter (floodfill, i2p::CreateDatabaseStoreMsg (leaseSet, m_PublishReplyToken, inbound));
		auto s = shared_from_this ();
		msg->onDrop = [s]()
			{
				boost::asio::post (s->GetService (), [s]()
					{
						s->m_PublishConfirmationTimer.cancel ();
						s->HandlePublishConfirmationTimer (boost::system::error_code(), 0);
					});
			};
		uint64_t publishConfirmationTimeout = PUBLISH_CONFIRMATION_TIMEOUT;
		publishConfirmationTimeout += inbound->LatencyIsKnown() ? (uint64_t)(inbound->GetMeanLatency())/1000LL :
			inbound->GetNumHops ()*(uint64_t)(i2p::tunnel::HIGH_LATENCY_PER_HOP)/1000LL;
		publishConfirmationTimeout += outbound->LatencyIsKnown() ? (uint64_t)(outbound->GetMeanLatency())/1000LL :
			outbound->GetNumHops ()*(uint64_t)(i2p::tunnel::HIGH_LATENCY_PER_HOP)/1000LL;
		m_PublishConfirmationTimer.expires_after (std::chrono::milliseconds(publishConfirmationTimeout));
		m_PublishConfirmationTimer.async_wait (std::bind (&LeaseSetDestination::HandlePublishConfirmationTimer,
			shared_from_this (), std::placeholders::_1, publishConfirmationTimeout));
		outbound->SendTunnelDataMsgTo (floodfill->GetIdentHash (), 0, msg);
		m_LastSubmissionTime = ts;
	}

	void LeaseSetDestination::HandlePublishConfirmationTimer (const boost::system::error_code& ecode, uint64_t publishConfirmationTimeout)
	{
		if (ecode != boost::asio::error::operation_aborted)
		{
			if (m_PublishReplyToken)
			{
				LogPrint (eLogWarning, "Destination: Publish confirmation was not received in ", publishConfirmationTimeout, " milliseconds or failed. will try again");
				m_PublishReplyToken = 0;
				Publish ();
			}
		}
	}

	void LeaseSetDestination::HandlePublishVerificationTimer (const boost::system::error_code& ecode)
	{
		if (ecode != boost::asio::error::operation_aborted)
		{
			auto ls = GetLeaseSetMt ();
			if (!ls)
			{
				LogPrint (eLogWarning, "Destination: Couldn't verify LeaseSet for ", GetIdentHash().ToBase32());
				return;
			}
			auto s = shared_from_this ();
			RequestLeaseSet (ls->GetStoreHash (),
				[s, ls](std::shared_ptr<const i2p::data::LeaseSet> leaseSet)
				{
					if (leaseSet)
					{
						if (*ls == *leaseSet)
						{
							// we got latest LeaseSet
							LogPrint (eLogDebug, "Destination: Published LeaseSet verified for ", s->GetIdentHash().ToBase32());
							s->m_PublishVerificationTimer.expires_after (std::chrono::seconds(PUBLISH_REGULAR_VERIFICATION_INTERNAL));
							s->m_PublishVerificationTimer.async_wait (std::bind (&LeaseSetDestination::HandlePublishVerificationTimer, s, std::placeholders::_1));
							return;
						}
						else
							LogPrint (eLogDebug, "Destination: LeaseSet is different than just published for ", s->GetIdentHash().ToBase32());
					}
					else
						LogPrint (eLogWarning, "Destination: Couldn't find published LeaseSet for ", s->GetIdentHash().ToBase32());
					// we have to publish again
					s->Publish ();
				});
		}
	}

	void LeaseSetDestination::HandlePublishDelayTimer (const boost::system::error_code& ecode)
	{
		if (ecode != boost::asio::error::operation_aborted)
			Publish ();
	}

	bool LeaseSetDestination::RequestDestination (const i2p::data::IdentHash& dest, RequestComplete requestComplete)
	{
		if (!m_Pool || !IsReady ())
		{
			if (requestComplete)
				boost::asio::post (m_Service, [requestComplete](void){requestComplete (nullptr);});
			return false;
		}
		boost::asio::post (m_Service, std::bind (&LeaseSetDestination::RequestLeaseSet, shared_from_this (), dest, requestComplete, nullptr));
		return true;
	}

	bool LeaseSetDestination::RequestDestinationWithEncryptedLeaseSet (std::shared_ptr<const i2p::data::BlindedPublicKey> dest, RequestComplete requestComplete)
	{
		if (!dest || !m_Pool || !IsReady ())
		{
			if (requestComplete)
				boost::asio::post (m_Service, [requestComplete](void){requestComplete (nullptr);});
			return false;
		}
		auto storeHash = dest->GetStoreHash ();
		auto leaseSet = FindLeaseSet (storeHash);
		if (leaseSet)
		{
			if (requestComplete)
				boost::asio::post (m_Service, [requestComplete, leaseSet](void){requestComplete (leaseSet);});
			return true;
		}
		boost::asio::post (m_Service, std::bind (&LeaseSetDestination::RequestLeaseSet, shared_from_this (), storeHash, requestComplete, dest));
		return true;
	}

	void LeaseSetDestination::CancelDestinationRequest (const i2p::data::IdentHash& dest, bool notify)
	{
		auto s = shared_from_this ();
		boost::asio::post (m_Service, [dest, notify, s](void)
			{
				auto it = s->m_LeaseSetRequests.find (dest);
				if (it != s->m_LeaseSetRequests.end ())
				{
					auto requestComplete = it->second;
					s->m_LeaseSetRequests.erase (it);
					if (notify && requestComplete) requestComplete->Complete (nullptr);
				}
			});
	}

	void LeaseSetDestination::CancelDestinationRequestWithEncryptedLeaseSet (std::shared_ptr<const i2p::data::BlindedPublicKey> dest, bool notify)
	{
		if (dest)
			CancelDestinationRequest (dest->GetStoreHash (), notify);
	}

	void LeaseSetDestination::RequestLeaseSet (const i2p::data::IdentHash& dest, RequestComplete requestComplete, std::shared_ptr<const i2p::data::BlindedPublicKey> requestedBlindedKey)
	{
		std::unordered_set<i2p::data::IdentHash> excluded;
		auto floodfill = i2p::data::netdb.GetClosestFloodfill (dest, excluded);
		if (floodfill)
		{
			auto request = std::make_shared<LeaseSetRequest> (m_Service);
			request->requestedBlindedKey = requestedBlindedKey; // for encrypted LeaseSet2
			if (requestComplete)
				request->requestComplete.push_back (requestComplete);
			auto ts = i2p::util::GetMillisecondsSinceEpoch ();
			auto ret = m_LeaseSetRequests.insert (std::pair<i2p::data::IdentHash, std::shared_ptr<LeaseSetRequest> >(dest,request));
			if (ret.second) // inserted
			{
				request->requestTime = ts;
				if (!SendLeaseSetRequest (dest, floodfill, request))
				{
					// try another
					LogPrint (eLogWarning, "Destination: Couldn't send LeaseSet request to ", floodfill->GetIdentHash ().ToBase64 (), ". Trying another");
					request->excluded.insert (floodfill->GetIdentHash ());
					floodfill = i2p::data::netdb.GetClosestFloodfill (dest, request->excluded);
					if (!SendLeaseSetRequest (dest, floodfill, request))
					{
						// request failed
						LogPrint (eLogWarning, "Destination: LeaseSet request for ", dest.ToBase32 (), " was not sent");
						m_LeaseSetRequests.erase (ret.first);
						if (requestComplete) requestComplete (nullptr);
					}
				}
			}
			else // duplicate
			{
				LogPrint (eLogInfo, "Destination: Request of LeaseSet ", dest.ToBase64 (), " is pending already");
				if (ts > ret.first->second->requestTime + MAX_LEASESET_REQUEST_TIMEOUT)
				{
					// something went wrong
					m_LeaseSetRequests.erase (ret.first);
					if (requestComplete) requestComplete (nullptr);
				}
				else if (requestComplete)
					ret.first->second->requestComplete.push_back (requestComplete);
			}
		}
		else
		{
			LogPrint (eLogError, "Destination: Can't request LeaseSet, no floodfills found");
			if (requestComplete) requestComplete (nullptr);
		}
	}

	bool LeaseSetDestination::SendLeaseSetRequest (const i2p::data::IdentHash& dest,
		std::shared_ptr<const i2p::data::RouterInfo> nextFloodfill, std::shared_ptr<LeaseSetRequest> request)
	{
		if (!request->replyTunnel || !request->replyTunnel->IsEstablished ())
			request->replyTunnel = m_Pool->GetNextInboundTunnel (nullptr, nextFloodfill->GetCompatibleTransports (false)); // outbound from floodfill
		if (!request->replyTunnel) LogPrint (eLogWarning, "Destination: Can't send LeaseSet request, no compatible inbound tunnels found");
		if (!request->outboundTunnel || !request->outboundTunnel->IsEstablished ())
			request->outboundTunnel = m_Pool->GetNextOutboundTunnel (nullptr, nextFloodfill->GetCompatibleTransports (true)); // inbound from floodfill
		if (!request->outboundTunnel) LogPrint (eLogWarning, "Destination: Can't send LeaseSet request, no compatible outbound tunnels found");

		if (request->replyTunnel && request->outboundTunnel)
		{
			request->excluded.insert (nextFloodfill->GetIdentHash ());
			request->requestTimeoutTimer.cancel ();

			uint8_t replyKey[32];
			uint64_t replyTag;
			RAND_bytes (replyKey, 32); // random session key
			RAND_bytes ((uint8_t *)&replyTag, 8); // random session tag
			AddECIESx25519Key (replyKey, replyTag);

			auto msg = WrapMessageForRouter (nextFloodfill,
				CreateLeaseSetDatabaseLookupMsg (dest, request->excluded, request->replyTunnel, replyKey, replyTag));
			auto s = shared_from_this ();
			msg->onDrop = [s, dest, request]()
				{
					boost::asio::post (s->GetService (), [s, dest, request]()
						{
							s->SendNextLeaseSetRequest (dest, request);
						});
				};
			request->outboundTunnel->SendTunnelDataMsgs (
				{
					i2p::tunnel::TunnelMessageBlock
					{
						i2p::tunnel::eDeliveryTypeRouter,
						nextFloodfill->GetIdentHash (), 0, msg
					}
				});

			uint64_t requestLeaseSetTimeout = LEASESET_REQUEST_TIMEOUT;
			requestLeaseSetTimeout += request->replyTunnel->LatencyIsKnown() ? (uint64_t)(request->replyTunnel->GetMeanLatency())/1000LL :
				request->replyTunnel->GetNumHops ()*(uint64_t)(i2p::tunnel::HIGH_LATENCY_PER_HOP)/1000LL;
			requestLeaseSetTimeout += request->outboundTunnel->LatencyIsKnown() ? (uint64_t)(request->outboundTunnel->GetMeanLatency())/1000LL :
				request->outboundTunnel->GetNumHops ()*(uint64_t)(i2p::tunnel::HIGH_LATENCY_PER_HOP)/1000LL;
			request->requestTimeoutTimer.expires_after (std::chrono::milliseconds(requestLeaseSetTimeout));
			request->requestTimeoutTimer.async_wait (std::bind (&LeaseSetDestination::HandleRequestTimoutTimer,
				shared_from_this (), std::placeholders::_1, dest, requestLeaseSetTimeout));
		}
		else
			return false;
		return true;
	}

	void LeaseSetDestination::HandleRequestTimoutTimer (const boost::system::error_code& ecode,
		const i2p::data::IdentHash& dest, uint64_t requestLeaseSetTimeout)
	{
		if (ecode != boost::asio::error::operation_aborted)
		{
			auto it = m_LeaseSetRequests.find (dest);
			if (it != m_LeaseSetRequests.end ())
			{
				bool done = false;
				uint64_t ts = i2p::util::GetMillisecondsSinceEpoch ();
				if (ts < it->second->requestTime + MAX_LEASESET_REQUEST_TIMEOUT)
				{
					auto floodfill = i2p::data::netdb.GetClosestFloodfill (dest, it->second->excluded);
					if (floodfill)
					{
						// reset tunnels, because one them might fail
						it->second->outboundTunnel = nullptr;
						it->second->replyTunnel = nullptr;
						done = !SendLeaseSetRequest (dest, floodfill, it->second);
					}
					else
						done = true;
				}
				else
				{
					LogPrint (eLogWarning, "Destination: ", dest.ToBase64 (), " was not found within ", requestLeaseSetTimeout, " seconds");
					done = true;
				}

				if (done)
				{
					auto requestComplete = it->second;
					m_LeaseSetRequests.erase (it);
					if (requestComplete) requestComplete->Complete (nullptr);
				}
			}
		}
	}

	void LeaseSetDestination::HandleCleanupTimer (const boost::system::error_code& ecode)
	{
		if (ecode != boost::asio::error::operation_aborted)
		{
			CleanupExpiredTags ();
			CleanupRemoteLeaseSets ();
			CleanupDestination ();
			m_CleanupTimer.expires_after (std::chrono::seconds (DESTINATION_CLEANUP_TIMEOUT +
				GetRng ()() % DESTINATION_CLEANUP_TIMEOUT_VARIANCE));
			m_CleanupTimer.async_wait (std::bind (&LeaseSetDestination::HandleCleanupTimer,
				shared_from_this (), std::placeholders::_1));
		}
	}

	void LeaseSetDestination::CleanupRemoteLeaseSets ()
	{
		auto ts = i2p::util::GetMillisecondsSinceEpoch ();
		std::lock_guard<std::mutex> lock(m_RemoteLeaseSetsMutex);
		for (auto it = m_RemoteLeaseSets.begin (); it != m_RemoteLeaseSets.end ();)
		{
			if (it->second->IsEmpty () || ts > it->second->GetExpirationTime ()) // leaseset expired
			{
				LogPrint (eLogDebug, "Destination: Remote LeaseSet ", it->second->GetIdentHash ().ToBase64 (), " expired");
				it = m_RemoteLeaseSets.erase (it);
			}
			else
				++it;
		}
	}

	ClientDestination::ClientDestination (boost::asio::io_context& service, const i2p::data::PrivateKeys& keys,
		bool isPublic, const i2p::util::Mapping * params):
		LeaseSetDestination (service, isPublic, params),
		m_Keys (keys), m_PreferredCryptoType (0), m_StreamingAckDelay (DEFAULT_INITIAL_ACK_DELAY),
		m_StreamingOutboundSpeed (DEFAULT_MAX_OUTBOUND_SPEED),
		m_StreamingInboundSpeed (DEFAULT_MAX_INBOUND_SPEED),
		m_StreamingMaxConcurrentStreams (DEFAULT_MAX_CONCURRENT_STREAMS),
		m_StreamingMaxConnsPerMinute (DEFAULT_MAX_CONNS_PER_MINUTE),
		m_StreamingMaxWindowSize (i2p::stream::MAX_WINDOW_SIZE),
		m_StreamingMaxResends (i2p::stream::MAX_NUM_RESEND_ATTEMPTS),
		m_IsStreamingAnswerPings (DEFAULT_ANSWER_PINGS), m_IsStreamingDontSign (DEFAULT_DONT_SIGN),
		m_LastPort (0), m_RefCounter (0), m_LastPublishedTimestamp (0), m_ReadyChecker(service)
	{
		if (keys.IsOfflineSignature () && GetLeaseSetType () == i2p::data::NETDB_STORE_TYPE_LEASESET)
			SetLeaseSetType (i2p::data::NETDB_STORE_TYPE_STANDARD_LEASESET2); // offline keys can be published with LS2 only

		// extract encryption type params for LS2
		std::set<i2p::data::CryptoKeyType> encryptionKeyTypes;
		if (params)
		{
			auto encryptionTypesStr = (*params)[I2CP_PARAM_LEASESET_ENCRYPTION_TYPE];
			if (!encryptionTypesStr.empty ())
			{
				// comma-separated values
				std::vector<std::string> values;
				boost::split(values, encryptionTypesStr, boost::is_any_of(","));
				for (auto& it1: values)
				{
					try
					{
						i2p::data::CryptoKeyType cryptoType = std::stoi(it1);
#if !OPENSSL_PQ
						if (cryptoType <= i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD) // skip PQ keys if not supported
#endif
						{
							if (!m_PreferredCryptoType && cryptoType)
								m_PreferredCryptoType = cryptoType; // first non-zero in the list
							encryptionKeyTypes.insert (cryptoType);
						}
					}
					catch (std::exception& ex)
					{
						LogPrint (eLogInfo, "Destination: Unexpected crypto type ", it1, ". ", ex.what ());
						continue;
					}
				}
			}
		}
		// if no encryption type specified use 0,4 or 0,4,6 if post quantum
		if (encryptionKeyTypes.empty ())
		{
			encryptionKeyTypes.insert ( { GetIdentity ()->GetCryptoKeyType (),
#if OPENSSL_PQ
				i2p::data::CRYPTO_KEY_TYPE_ECIES_MLKEM768_X25519_AEAD,
#endif
				i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD });
#if OPENSSL_PQ
			m_PreferredCryptoType = i2p::data::CRYPTO_KEY_TYPE_ECIES_MLKEM768_X25519_AEAD;
#else
			m_PreferredCryptoType = i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD;
#endif
		}

		for (auto& it: encryptionKeyTypes)
		{
			auto encryptionKey = std::make_shared<i2p::crypto::LocalEncryptionKey> (it);
			if (IsPublic ())
				PersistTemporaryKeys (encryptionKey);
			else
				encryptionKey->GenerateKeys ();
			encryptionKey->CreateDecryptor ();
			if (it > i2p::data::CRYPTO_KEY_TYPE_ELGAMAL && GetLeaseSetType () == i2p::data::NETDB_STORE_TYPE_LEASESET)
				SetLeaseSetType (i2p::data::NETDB_STORE_TYPE_STANDARD_LEASESET2); // Only DSA can use LeaseSet1
			m_EncryptionKeys.emplace (it, encryptionKey);
		}

		if (IsPublic ())
			LogPrint (eLogInfo, "Destination: Local address ", GetIdentHash().ToBase32 (), " created");

		try
		{
			if (params)
			{
				// extract streaming params
				params->Get (I2CP_PARAM_STREAMING_INITIAL_ACK_DELAY, m_StreamingAckDelay);
				params->Get (I2CP_PARAM_STREAMING_MAX_OUTBOUND_SPEED, m_StreamingOutboundSpeed);
				params->Get (I2CP_PARAM_STREAMING_MAX_INBOUND_SPEED, m_StreamingInboundSpeed);
				params->Get (I2CP_PARAM_STREAMING_MAX_CONCURRENT_STREAMS, m_StreamingMaxConcurrentStreams);
				params->Get (I2CP_PARAM_STREAMING_MAX_CONNS_PER_MINUTE, m_StreamingMaxConnsPerMinute);
				if (params->Get (I2CP_PARAM_STREAMING_MAX_WINDOW_SIZE, m_StreamingMaxWindowSize) &&
					(m_StreamingMaxWindowSize < i2p::stream::MIN_WINDOW_SIZE))
						m_StreamingMaxWindowSize = i2p::stream::MIN_WINDOW_SIZE;
				params->Get (I2CP_PARAM_STREAMING_ANSWER_PINGS, m_IsStreamingAnswerPings);
				params->Get (I2CP_PARAM_STREAMING_DONT_SIGN, m_IsStreamingDontSign);
                params->Get (I2CP_PARAM_STREAMING_MAX_RESENDS, m_StreamingMaxResends);

				if (GetLeaseSetType () == i2p::data::NETDB_STORE_TYPE_ENCRYPTED_LEASESET2)
				{
					// authentication for encrypted LeaseSet
					auto authType = GetAuthType ();
					if (authType > 0)
					{
						m_AuthKeys = std::make_shared<std::vector<i2p::data::AuthPublicKey> >();
						if (authType == i2p::data::ENCRYPTED_LEASESET_AUTH_TYPE_DH)
							ReadAuthKey (I2CP_PARAM_LEASESET_CLIENT_DH, params);
						else if (authType == i2p::data::ENCRYPTED_LEASESET_AUTH_TYPE_PSK)
							ReadAuthKey (I2CP_PARAM_LEASESET_CLIENT_PSK, params);
						else
							LogPrint (eLogError, "Destination: Unexpected auth type: ", authType);
						if (m_AuthKeys->size ())
							LogPrint (eLogInfo, "Destination: ", m_AuthKeys->size (), " auth keys read");
						else
						{
							LogPrint (eLogCritical, "Destination: No auth keys read for auth type: ", authType);
							m_AuthKeys = nullptr;
						}
					}
				}
			}
		}
		catch (std::exception & ex)
		{
			LogPrint(eLogCritical, "Destination: Unable to parse parameters for destination: ", ex.what());
		}
	}

	ClientDestination::~ClientDestination ()
	{
	}

	void ClientDestination::Start ()
	{
		// Idempotent: a second Start() on a running destination must not re-create
		// m_StreamingDestination (orphaning the live one) nor re-arm leaseset/pool.
		if (m_StreamingDestination) return;
		LeaseSetDestination::Start ();
		m_StreamingDestination = std::make_shared<i2p::stream::StreamingDestination> (GetSharedFromThis ()); // TODO:
		m_StreamingDestination->Start ();
		for (auto& it: m_StreamingDestinationsByPorts)
			it.second->Start ();
	}

	void ClientDestination::Stop ()
	{
		LogPrint(eLogDebug, "Destination: Stopping destination ", GetIdentHash().ToBase32(), ".b32.i2p");
		m_ReadyChecker.cancel();
		LogPrint(eLogDebug, "Destination: -> Stopping Streaming Destination");
		m_StreamingDestination->Stop ();
		//m_StreamingDestination->SetOwner (nullptr);
		m_StreamingDestination = nullptr;

		LogPrint(eLogDebug, "Destination: -> Stopping Streaming Destination by ports");
		for (auto& it: m_StreamingDestinationsByPorts)
		{
			it.second->Stop ();
			//it.second->SetOwner (nullptr);
		}
		m_StreamingDestinationsByPorts.clear ();
		m_LastStreamingDestination = nullptr;

		if (m_DatagramDestination)
		{
			LogPrint(eLogDebug, "Destination: -> Stopping Datagram Destination");
			m_DatagramDestination = nullptr;
		}
		LeaseSetDestination::Stop ();
		LogPrint(eLogDebug, "Destination: -> Stopping done");
	}

	void ClientDestination::SetPrivateKeys (const i2p::data::PrivateKeys& keys)
	{
		if (m_StreamingDestination) m_StreamingDestination->Stop (); // close all streams
		CleanUp (); // delete sessions and tags
		auto pool = GetTunnelPool ();
		if (pool) pool->DetachTunnels ();
		m_Keys = keys;
		// update static keys
		for (auto it: m_EncryptionKeys)
			if (it.second)
			{
				it.second->GenerateKeys ();
				it.second->CreateDecryptor ();
			}
		if (m_StreamingDestination) m_StreamingDestination->Start ();
	}

	void ClientDestination::UpdateOfflineSignature (const i2p::data::PrivateKeys& keys)
	{
		// Adopt a newer offline transient of the same identity in place, on the
		// destination's service so it stays single-threaded with LeaseSet and stream
		// signing. Only the transient is refreshed, the identity is unchanged.
		if (!keys.IsOfflineSignature ()) return;
		boost::asio::post (GetService (), [s = GetSharedFromThis (), keys]()
		{
			if (!s->m_Keys.IsOfflineSignature ()) return;
			if (keys.GetPublic ()->GetIdentHash () != s->GetIdentHash ()) return;
			const auto& next = keys.GetOfflineSignature ();
			const auto& cur = s->m_Keys.GetOfflineSignature ();
			if (next == cur) return; // same transient
			if (bufbe32toh (next.data ()) < bufbe32toh (cur.data ())) return; // do not shorten validity
			LogPrint (eLogInfo, "Destination: Refreshing offline signature for ",
				s->GetIdentHash ().ToBase32 (), ", transient expires ", bufbe32toh (next.data ()));
			s->m_Keys.UpdateOfflineSignature (keys);
			s->UpdateLeaseSet ();
		});
	}

	void ClientDestination::HandleDataMessage (const uint8_t * buf, size_t len,
		i2p::garlic::ECIESX25519AEADRatchetSession * from)
	{
		if (len < 14) // 4-byte length prefix, then fromPort/toPort/protocol read at offsets up to 9 past it
		{
			LogPrint (eLogWarning, "Destination: Data message is too short ", len);
			return;
		}
		uint32_t length = bufbe32toh (buf);
		if(length > len - 4)
		{
			LogPrint(eLogError, "Destination: Data message length ", length, " exceeds buffer length ", len);
			return;
		}
		buf += 4;
		// we assume I2CP payload
		uint16_t fromPort = bufbe16toh (buf + 4), // source
			toPort = bufbe16toh (buf + 6); // destination
		switch (buf[9])
		{
			case PROTOCOL_TYPE_STREAMING:
			{
				// streaming protocol
				if (toPort != m_LastPort || !m_LastStreamingDestination)
				{
					m_LastStreamingDestination = GetStreamingDestination (toPort);
					if (!m_LastStreamingDestination)
						m_LastStreamingDestination = m_StreamingDestination; // if no destination on port use default
					m_LastPort = toPort;
				}
				if (m_LastStreamingDestination)
					m_LastStreamingDestination->HandleDataMessagePayload (buf, length, from);
				else
					LogPrint (eLogError, "Destination: Missing streaming destination");
			}
			break;
			case PROTOCOL_TYPE_DATAGRAM:
			case PROTOCOL_TYPE_RAW:
			case PROTOCOL_TYPE_DATAGRAM2:
			case PROTOCOL_TYPE_DATAGRAM3:
				// datagram protocol
				if (m_DatagramDestination)
					m_DatagramDestination->HandleDataMessagePayload (fromPort, toPort, buf, length, buf[9], from);
				else
					LogPrint (eLogError, "Destination: Missing datagram destination");
			break;
			default:
				LogPrint (eLogError, "Destination: Data: Unexpected protocol ", buf[9]);
		}
	}

	void ClientDestination::CreateStream (StreamRequestComplete streamRequestComplete, const i2p::data::IdentHash& dest, uint16_t port)
	{
		if (!streamRequestComplete)
		{
			LogPrint (eLogError, "Destination: Request callback is not specified in CreateStream");
			return;
		}
		auto leaseSet = FindLeaseSet (dest);
		if (leaseSet)
		{
			auto stream = (!leaseSet->IsIncompatibleCrypto ()) ? CreateStream (leaseSet, port) : nullptr;
			boost::asio::post (GetService (), [streamRequestComplete, stream]()
				{
					streamRequestComplete(stream);
				});
		}
		else
		{
			auto s = GetSharedFromThis ();
			RequestDestination (dest,
				[s, streamRequestComplete, port](std::shared_ptr<const i2p::data::LeaseSet> ls)
				{
					if (ls && !ls->IsIncompatibleCrypto ())
						streamRequestComplete(s->CreateStream (ls, port));
					else
						streamRequestComplete (nullptr);
				});
		}
	}

	void ClientDestination::CreateStream (StreamRequestComplete streamRequestComplete, std::shared_ptr<const i2p::data::BlindedPublicKey> dest, uint16_t port)
	{
		if (!streamRequestComplete)
		{
			LogPrint (eLogError, "Destination: Request callback is not specified in CreateStream");
			return;
		}
		auto s = GetSharedFromThis ();
		RequestDestinationWithEncryptedLeaseSet (dest,
			[s, streamRequestComplete, port](std::shared_ptr<i2p::data::LeaseSet> ls)
			{
				if (ls && !ls->IsIncompatibleCrypto ())
					streamRequestComplete(s->CreateStream (ls, port));
				else
					streamRequestComplete (nullptr);
			});
	}

	template<typename Dest>
	std::shared_ptr<i2p::stream::Stream> ClientDestination::CreateStreamSync (const Dest& dest, uint16_t port)
	{
		volatile bool done = false;
		std::shared_ptr<i2p::stream::Stream> stream;
		std::condition_variable streamRequestComplete;
		std::mutex streamRequestCompleteMutex;
		CreateStream (
			[&done, &streamRequestComplete, &streamRequestCompleteMutex, &stream](std::shared_ptr<i2p::stream::Stream> s)
		    {
				stream = s;
				std::unique_lock<std::mutex> l(streamRequestCompleteMutex);
				streamRequestComplete.notify_all ();
				done = true;
			},
		    dest, port);
		while (!done)
		{
			std::unique_lock<std::mutex> l(streamRequestCompleteMutex);
			if (!done)
				streamRequestComplete.wait (l);
		}
		return stream;
	}

	std::shared_ptr<i2p::stream::Stream> ClientDestination::CreateStream (const i2p::data::IdentHash& dest, uint16_t port)
	{
		return CreateStreamSync (dest, port);
	}

	std::shared_ptr<i2p::stream::Stream> ClientDestination::CreateStream (std::shared_ptr<const i2p::data::BlindedPublicKey> dest, uint16_t port)
	{
		return CreateStreamSync (dest, port);
	}

	std::shared_ptr<i2p::stream::Stream> ClientDestination::CreateStream (std::shared_ptr<const i2p::data::LeaseSet> remote, uint16_t port)
	{
		if (m_StreamingDestination)
			return m_StreamingDestination->CreateNewOutgoingStream (remote, port);
		else
			return nullptr;
	}

	void ClientDestination::SendPing (const i2p::data::IdentHash& to)
	{
		if (m_StreamingDestination)
		{
			auto leaseSet = FindLeaseSet (to);
			if (leaseSet)
				m_StreamingDestination->SendPing (leaseSet);
			else
			{
				auto s = m_StreamingDestination;
				RequestDestination (to,
					[s](std::shared_ptr<const i2p::data::LeaseSet> ls)
					{
						if (ls) s->SendPing (ls);
					});
			}
		}
	}

	void ClientDestination::SendPing (std::shared_ptr<const i2p::data::BlindedPublicKey> to)
	{
		auto s = m_StreamingDestination;
		RequestDestinationWithEncryptedLeaseSet (to,
			[s](std::shared_ptr<const i2p::data::LeaseSet> ls)
			{
				if (ls) s->SendPing (ls);
			});
	}

	std::shared_ptr<i2p::stream::StreamingDestination> ClientDestination::GetStreamingDestination (uint16_t port) const
	{
		if (port)
		{
			auto it = m_StreamingDestinationsByPorts.find (port);
			if (it != m_StreamingDestinationsByPorts.end ())
				return it->second;
		}
		else // if port is zero, use default destination
			return m_StreamingDestination;
		return nullptr;
	}

	void ClientDestination::AcceptStreams (const i2p::stream::StreamingDestination::Acceptor& acceptor)
	{
		if (m_StreamingDestination)
			m_StreamingDestination->SetAcceptor (acceptor);
	}

	void ClientDestination::StopAcceptingStreams ()
	{
		if (m_StreamingDestination)
			m_StreamingDestination->ResetAcceptor ();
	}

	bool ClientDestination::IsAcceptingStreams () const
	{
		if (m_StreamingDestination)
			return m_StreamingDestination->IsAcceptorSet ();
		return false;
	}

	void ClientDestination::AcceptOnce (const i2p::stream::StreamingDestination::Acceptor& acceptor)
	{
		if (m_StreamingDestination)
			m_StreamingDestination->AcceptOnce (acceptor);
	}

	std::shared_ptr<i2p::stream::StreamingDestination> ClientDestination::CreateStreamingDestination (uint16_t port, bool gzip)
	{
		auto dest = std::make_shared<i2p::stream::StreamingDestination> (GetSharedFromThis (), port, gzip);
		if (port)
			m_StreamingDestinationsByPorts[port] = dest;
		else // update default
			m_StreamingDestination = dest;
		return dest;
	}

	std::shared_ptr<i2p::stream::StreamingDestination> ClientDestination::RemoveStreamingDestination (uint16_t port)
	{
		if (port)
		{
			auto it = m_StreamingDestinationsByPorts.find (port);
			if (it != m_StreamingDestinationsByPorts.end ())
			{
				auto ret = it->second;
				m_StreamingDestinationsByPorts.erase (it);
				return ret;
			}
		}
		return nullptr;
	}

	std::shared_ptr<i2p::datagram::DatagramDestination> ClientDestination::CreateDatagramDestination (bool gzip,
		i2p::datagram::DatagramVersion version)
	{
		if (!m_DatagramDestination)
		{
			if (!GetNumRatchetInboundTags ())
				SetNumRatchetInboundTags (i2p::garlic::ECIESX25519_MAX_NUM_GENERATED_TAGS); // set max tags if not specified
			m_DatagramDestination = std::make_shared<i2p::datagram::DatagramDestination> (GetSharedFromThis (), gzip, version);
		}
		return m_DatagramDestination;
	}

	std::vector<std::shared_ptr<const i2p::stream::Stream> > ClientDestination::GetAllStreams () const
	{
		std::vector<std::shared_ptr<const i2p::stream::Stream> > ret;
		if (m_StreamingDestination)
			ret = m_StreamingDestination->GetStreamsList ();
		for (auto& it: m_StreamingDestinationsByPorts)
		{
			auto streams = it.second->GetStreamsList ();
			ret.insert (ret.end (), streams.begin (), streams.end ());
		}
		return ret;
	}

	void ClientDestination::PersistTemporaryKeys (std::shared_ptr<i2p::crypto::LocalEncryptionKey> keys)
	{
		if (!keys) return;
		std::string ident = GetIdentHash().ToBase32();
		std::string path  = i2p::fs::DataDirPath("destinations", ident + "." + std::to_string (keys->keyType) + ".dat");
		std::ifstream f(path, std::ifstream::binary);
		if (f)
		{
			size_t len = 0;
			if (keys->keyType == i2p::data::CRYPTO_KEY_TYPE_ELGAMAL)
				len = 512;
			else if (keys->keyType == i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD)
			{
				f.seekg (0, std::ios::end);
				len = f.tellg();
				f.seekg (0, std::ios::beg);
			}

			if (len == 512)
			{
				char pub[256], priv[256];
				f.read (pub, 256);
				memcpy (keys->pub.data(), pub, keys->pub.size());
				f.read (priv, 256);
				memcpy (keys->priv.data (), priv, keys->priv.size ());
			}
			else
			{
				f.read ((char *)keys->pub.data(), keys->pub.size());
				f.read ((char *)keys->priv.data(), keys->priv.size());
			}
			if (f)
				return;
			else
				LogPrint(eLogWarning, "Destination: Can't read keys from ", path);
		}

		LogPrint (eLogInfo, "Destination: Creating new temporary keys of type ", keys->keyType, " for address ", ident, ".b32.i2p");
		memset (keys->priv.data (), 0, keys->priv.size ());
		memset (keys->pub.data (), 0, keys->pub.size ());
		keys->GenerateKeys ();

		std::ofstream f1 (path, std::ofstream::binary | std::ofstream::out);
		if (f1)
		{
			f1.write ((char *)keys->pub.data (), keys->pub.size ());
			f1.write ((char *)keys->priv.data (), keys->priv.size ());
		}
		if (!f1)
			LogPrint(eLogError, "Destination: Can't save keys to ", path);
	}

	void ClientDestination::CreateNewLeaseSet (const std::vector<std::shared_ptr<i2p::tunnel::InboundTunnel> >& tunnels)
	{
		std::shared_ptr<i2p::data::LocalLeaseSet> leaseSet;
		if (GetLeaseSetType () == i2p::data::NETDB_STORE_TYPE_LEASESET)
		{
			auto it = m_EncryptionKeys.find (i2p::data::CRYPTO_KEY_TYPE_ELGAMAL);
			if (it != m_EncryptionKeys.end ())
			{
				leaseSet = std::make_shared<i2p::data::LocalLeaseSet> (GetIdentity (), it->second->pub.data (), tunnels);
				// sign
				Sign (leaseSet->GetBuffer (), leaseSet->GetBufferLen () - leaseSet->GetSignatureLen (), leaseSet->GetSignature ());
			}
			else
				LogPrint (eLogError, "Destinations: Wrong encryption key type for LeaseSet type 1");
		}
		else
		{
			// standard LS2 (type 3) first
			if (m_EncryptionKeys.empty ())
			{
				LogPrint (eLogError, "Destinations: No encryption keys");
				return;
			}

			i2p::data::LocalLeaseSet2::EncryptionKeys keySections;
			std::shared_ptr<const i2p::crypto::LocalEncryptionKey> preferredSection;
			if (m_EncryptionKeys.size () == 1)
				preferredSection = m_EncryptionKeys.begin ()->second; // only key
			else
			{
				for (const auto& it: m_EncryptionKeys)
					if (it.first == m_PreferredCryptoType)
						preferredSection = it.second;
					else
						keySections.push_front (it.second); // higher key type should appear first
			}
			if (preferredSection)
				keySections.push_front (preferredSection); // make preferred first

			auto publishedTimestamp = i2p::util::GetSecondsSinceEpoch ();
			if (publishedTimestamp <= m_LastPublishedTimestamp)
			{
				LogPrint (eLogDebug, "Destination: LeaseSet update at the same second");
				publishedTimestamp++; // force newer timestamp
			}
			bool isPublishedEncrypted = GetLeaseSetType () == i2p::data::NETDB_STORE_TYPE_ENCRYPTED_LEASESET2;
			auto ls2 = std::make_shared<i2p::data::LocalLeaseSet2> (i2p::data::NETDB_STORE_TYPE_STANDARD_LEASESET2,
				m_Keys, keySections, tunnels, IsPublic (), publishedTimestamp, isPublishedEncrypted);
			if (isPublishedEncrypted) // encrypt if type 5
				ls2 = std::make_shared<i2p::data::LocalEncryptedLeaseSet2> (ls2, m_Keys, GetAuthType (), m_AuthKeys);
			leaseSet = ls2;
			m_LastPublishedTimestamp = publishedTimestamp;
		}
		SetLeaseSet (leaseSet);
	}

	void ClientDestination::CleanupDestination ()
	{
		if (m_DatagramDestination) m_DatagramDestination->CleanUp ();
	}

	bool ClientDestination::Decrypt (const uint8_t * encrypted, uint8_t * data, i2p::data::CryptoKeyType preferredCrypto) const
	{
		std::shared_ptr<i2p::crypto::LocalEncryptionKey> encryptionKey;
		if (!m_EncryptionKeys.empty ())
		{
			if (m_EncryptionKeys.rbegin ()->first == preferredCrypto)
				encryptionKey = m_EncryptionKeys.rbegin ()->second;
			else
			{
				auto it = m_EncryptionKeys.find (preferredCrypto);
				if (it != m_EncryptionKeys.end ())
					encryptionKey = it->second;
			}
			if (!encryptionKey)
				encryptionKey = m_EncryptionKeys.rbegin ()->second;
		}
		if (encryptionKey)
			return encryptionKey->decryptor->Decrypt (encrypted, data);
		else
			LogPrint (eLogError, "Destinations: Decryptor is not set");
		return false;
	}

	bool ClientDestination::SupportsEncryptionType (i2p::data::CryptoKeyType keyType) const
	{
#if __cplusplus >= 202002L // C++20
		return m_EncryptionKeys.contains (keyType);
#else
		return m_EncryptionKeys.count (keyType) > 0;
#endif
	}

	i2p::data::CryptoKeyType ClientDestination::GetRatchetsHighestCryptoType () const
	{
		if (m_EncryptionKeys.empty ()) return 0;
		auto cryptoType = m_EncryptionKeys.rbegin ()->first;
		return cryptoType >= i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD ? cryptoType : 0;
	}

	const uint8_t * ClientDestination::GetEncryptionPublicKey (i2p::data::CryptoKeyType keyType) const
	{
		auto it = m_EncryptionKeys.find (keyType);
		if (it != m_EncryptionKeys.end ())
			return it->second->pub.data ();
		return nullptr;
	}

	void ClientDestination::ReadAuthKey (const std::string& group, const i2p::util::Mapping * params)
	{
		for (const auto& it: params->GetOptions ())
			if (it.first.length () >= group.length () && !it.first.compare (0, group.length (), group))
			{
				auto pos = it.second.find (':');
				if (pos != std::string::npos)
				{
					i2p::data::AuthPublicKey pubKey;
					if (pubKey.FromBase64 (it.second.substr (pos+1)))
						m_AuthKeys->push_back (pubKey);
					else
						LogPrint (eLogCritical, "Destination: Unexpected auth key: ", it.second.substr (pos+1));
				}
			}
	}

	bool ClientDestination::DeleteStream (uint32_t recvStreamID)
	{
		if (m_StreamingDestination->DeleteStream (recvStreamID))
			return true;
		for (auto it: m_StreamingDestinationsByPorts)
			if (it.second->DeleteStream (recvStreamID))
				return true;
		return false;
	}

	RunnableClientDestination::RunnableClientDestination (const i2p::data::PrivateKeys& keys,
		bool isPublic, const i2p::util::Mapping * params):
		RunnableService ("Destination"), ClientDestination (GetIOService (), keys, isPublic, params)
	{
		if (!GetNickname ().empty ())
			RunnableService::SetName (GetNickname ());
	}

	RunnableClientDestination::~RunnableClientDestination ()
	{
		if (IsRunning ())
			Stop ();
	}

	void RunnableClientDestination::Start ()
	{
		if (!IsRunning ())
		{
			ClientDestination::Start ();
			StartIOService ();
		}
	}

	void RunnableClientDestination::Stop ()
	{
		if (IsRunning ())
		{
			// the destination's own thread may still be handling packets of this
			// very destination, so tear it down there rather than under the caller
			if (GetIOService ().get_executor ().running_in_this_thread ())
				ClientDestination::Stop ();
			else
			{
				std::promise<void> done;
				boost::asio::post (GetIOService (), [this, &done]()
					{
						ClientDestination::Stop ();
						done.set_value ();
					});
				done.get_future ().wait ();
			}
			StopIOService ();
		}
	}

}
}
