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path: root/src/network/connection.cpp

	Commit message (Collapse)	Author	Age
*	Fix build on gcc 5.0 (#7586)	zeuner	2018-07-26
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*	Remove legacy client handling code.	Lars Hofhansl	2018-07-14
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*	Fix bug setting channel window size.	Lars Hofhansl	2018-07-13
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*	RTT fixes (#7428)	you	2018-06-23
| | | | | | | | | | | |	* Few code updates * Do not show average RTT before timing out * Fix unwanted integer division in RTTStatistics * Fix float format, prettier jitter calculation * Use +=, 0.1f -> 100.0f for stronger average updates
*	Add session_t typedef + remove unused functions (#6470)	Loïc Blot	2017-09-27
| | | | | |	* Add session_t typedef + remove unused functions u16 peer_id is used everywhere, to be more consistent and permit some evolutions on this type in the future (i'm working on a PoC), uniformize u16 peer_id to SessionId peer_id
*	Network part requires SharedBuffers to be pass as value	Loic Blot	2017-09-03
| | | | | |	This can trigger unreproductible crashes due to concurrency problem on SharedBuffers This fixes #6354
*	Network cleanup (#6310)	Loïc Blot	2017-08-25
| | | | | | | | | | | | | |	* Move Connection threads to dedicated files + various cleanups * ConnectionReceiveThread::processPacket now uses function pointer table to route MT packet types * Various code style fixes * Code style with clang-format * Various SharedBuffer copy removal * SharedBuffer cannot be copied anymore using Buffer * Fix many SharedBuffer copy (thanks to delete operator)
*	Network cleanup (#6302)	Loïc Blot	2017-08-24
| | | | | | | | | | | | | | | | | | | | | | |	* Cleanup network headers * Move peerhandler to a specific header to reduce compilation times * Move socket.cpp/h to network folder * More work * Network code cleanups * Move socket.{cpp,h} to network folder * Move Address object to network/address.{cpp,h} * Move network exceptions to network/networkexceptions.h * Client: use unique_ptr for Connection * Server/ClientIface: use shared_ptr for Connection * Format fixes * Remove socket.cpp socket.h from clang-format whitelist * Also fix NetworkPacket code style & make it under clang-format
*	Modernize source code: last part (#6285)	Loïc Blot	2017-08-20
| | | | | | | | | | |	* Modernize source code: last par * Use empty when needed * Use emplace_back instead of push_back when needed * For range-based loops * Initializers fixes * constructors, destructors default * c++ C stl includes
*	Code modernization: subfolders (#6283)	Loïc Blot	2017-08-19
| | | | | | | | | | | | |	* Code modernization: subfolders Modernize various code on subfolders client, network, script, threading, unittests, util * empty function * default constructor/destructor * for range-based loops * use emplace_back instead of push_back * C++ STL header style * Make connection.cpp readable in a pointed place + typo
*	Cleanup various headers to reduce compilation times (#6255)	Loïc Blot	2017-08-16
| | | |	* Cleanup various headers to reduce compilation times
*	C++11 cleanup on constructors dir network (#6021)	Vincent Glize	2017-06-21
| | | |	* C++11 cleanup on constructors dir network
*	Use C++11 mutexes only (remove compat code) (#5922)	Loïc Blot	2017-06-06
| | | |	* Fix event LINT & remove default constructor/destructors * remove compat code & modernize autolock header
*	Fix Travis/unittest broken since b662a45	SmallJoker	2017-04-29
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*	Fix various performance issues reported by cppcheck (#5628)	Loïc Blot	2017-04-21
| | |	* Also remove 1 non declared but defined functions
*	Use the outgoing split sequence number for every outgoing packet (#4864)	Rogier-5	2016-12-29
| | | | |	(instead of the last incoming sequence number...) Fixes #4848
*	Sapier's fix for the RESEND RELIABLE problem (#4170)	Robert Kiraly	2016-06-03
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*	Tolerate packet reordering in the early init process	est31	2016-05-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |	Fixes a bug where packet reordering made the server give the client two peer ids instead of one. This in turn confused reliable packet sending and made connecting to the server fail. The client usually sends three packets at init: one "dummy" packet consisting of two 0 bytes, and the init packet as well as its legacy counterpart. The last one can be turned off since commit af30183124d40a969040d7de4b3a487feec466e4, but this is of lower relevance for the bug. The relevant part here is that network packet reorder (which is a normal occurence) can make the packets reach the server in different order. If reorder puts the dummy packet further behind, the following would happen before the patch: 1. The server will get one of the init packets on channel 1 and assign the client a peer id, as the packet will have zero as peer id. 2. The server sends a CONTROLTYPE_SET_PEER_ID packet to inform the client of the peer id. 3. The next packet from the client will contain the peer id set by the server. 4. The server sets the m_has_sent_with_id member for the client's peer structure to true. 5. Now the dummy packet arrives. It has a peer id of zero, therefore the server searches whether it already has a peer id for the address the packet was sent from. The search fails because m_has_sent_with_id was set to true and the server only searched for peers with m_has_sent_with_id set to false. 6. In a working setup, the server would assign the dummy packet to the correct peer id. However the server instead now assigns a second peer id and peer structure to the peer, and assign the packet to that new peer. 7. In order to inform the peer of its peer id, the server sends a CONTROLTYPE_SET_PEER_ID command packet, reliably, to the peer. This packet uses the new peer id. 8. The client sends an ack to that packet, not with the new peer id but with the peer id sent in 2. 9. This packet reaches the server, but it drops the ACK as the peer id does not map to any un-ACK-ed packets with that seqnum. The same time, the server still waits for an ACK with the new peer id, which of course won't come. This causes the server to periodically re-try sending that packet, and the client ACKing it each time. Steps 7-9 cause annoyances and erroneous output, but don't cause the connection failure itself. The actual mistake that causes the connection failure happens in 6: The server does not assign the dummy packet to the correct peer, but to a newly created one. Therefore, all further packets sent by the client on channel 0 are now buffered by the server as it waits for the dummy packet to reach the peer, which of course doesn't happen as the server assigned that packet to the second peer it created for the client. This makes the connection code indefinitely buffer the TOSERVER_CLIENT_READY packet, not passing it to higher level code, which stalls the continuation of the further init process indefinitely and causes the actual bug. Maybe this can be caused by reordered init packets as well, the only studied case was where network has reliably reordered the dummy packet to get sent after the init packets. The patch fixes the bug by not ignoring peers where m_has_sent_with_id has been set anymore. The other changes of the patch are just cleanups of unused methods and fields and additional explanatory comments. One could think of alternate ways to fix the bug: * The client could simply take the new peer id and continue communicating with that. This is however worse than the fix as it requires the peer id set command to be sent reliably (which currently happens, but it cant be changed anymore). Also, such a change would require both server and client to be patched in order for the bug to be fixed, as right now the client ignores peer id set commands after the peer id is different from PEER_ID_INEXISTENT and the server requires modification too to change the peer id internally. And, most importantly, right now we guarantee higher level server code that the peer id for a certain peer does not change. This guarantee would have to be broken, and it would require much larger changes to the server than this patch means. * One could stop sending the dummy packet. One may be unsure whether this is a good idea, as the meaning of the dummy packet is not known (it might be there for something important), and as it is possible that the init packets may cause this problem as well (although it may be possible too that they can't cause this). Thanks to @auouymous who had originally reported this bug and who has helped patiently in finding its cause.
*	Always use errorstream for DEBUG_EXCEPTION_HANDLER	ShadowNinja	2015-10-14
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*	Use warningstream for log messages with WARNING	ShadowNinja	2015-10-14
| | | |	Remove DTIME macro and its uses, too
*	Change i++ to ++i	David Jones	2015-08-25
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*	Clean up threading	ShadowNinja	2015-08-23
| | | | | | | | | | | | | | | | | | | |	* Rename everything. * Strip J prefix. * Change UpperCamelCase functions to lowerCamelCase. * Remove global (!) semaphore count mutex on OSX. * Remove semaphore count getter (unused, unsafe, depended on internal API functions on Windows, and used a hack on OSX). * Add `Atomic<type>`. * Make `Thread` handle thread names. * Add support for C++11 multi-threading. * Combine pthread and win32 sources. * Remove `ThreadStarted` (unused, unneeded). * Move some includes from the headers to the sources. * Move all of `Event` into its header (allows inlining with no new includes). * Make `Event` use `Semaphore` (except on Windows). * Move some porting functions into `Thread`. * Integrate logging with `Thread`. * Add threading test.
*	Remove unused function from connection.{cpp,h}	nerzhul	2015-08-15
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*	connection: Make assertions non-fatal for received data	kwolekr	2015-08-05
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*	connection.cpp: remove unused constructor	Loic Blot	2015-07-14
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*	Move globals from main.cpp to more sane locations	Craig Robbins	2015-04-01
| | | | | | | | | | | |	Move debug streams to log.cpp|h Move GUI-related globals to clientlauncher Move g_settings and g_settings_path to settings.cpp|h Move g_menuclouds to clouds.cpp|h Move g_profiler to profiler.cpp|h
*	Connection::Receive(): receive Network Packet instead of SharedBuffer<u8>.	Loic Blot	2015-03-31
| | | | | | |	Because we get a Buffer<u8> from ConnectionEvent, don't convert it to SharedBuffer<u8> and return it to Server/Client::Receive which will convert it to NetworkPacket Instead, put the Buffer<u8> directly to NetworkPacket and return it to packet processing This remove a long existing memory copy Also check the packet size directly into Connection::Receive instead of packet processing
*	RunCommandQueues: little optimization	Loic Blot	2015-03-31
| | | |	remove command from queue on success, else do nothing, instead of remove command from queue and push it front on success
*	Typo in getOutgoingSequenceNumber => successfull to successful	Loic Blot	2015-03-31
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*	queued_commands must be a std::deque. RunCommandQueues needs to push packet ↵	Loic Blot	2015-03-29
| | | |	on front, not back
*	Remove unused ConnectionCommand::sendToAll function. ↵	Loic Blot	2015-03-22
| | | | | |	NetworkPacket::oldForgePacket returns Buffer instead of SharedBuffer and is used in ConnectionCommand instead of Connection::Send This remove the NetworkPacket buffer => SharedBuffer => Buffer copy. Now NetworkPacket => Buffer
*	Replace NetworkPacket pointers to references	Loic Blot	2015-03-13
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*	For usages of assert() that are meant to persist in Release builds (when ↵	Craig Robbins	2015-03-07
| | | |	NDEBUG is defined), replace those usages with persistent alternatives
*	Remove Queue class which uses std::list and use native std::queue	Loic Blot	2015-03-05
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*	Fix some memory leaks on packet sending.	Loic Blot	2015-02-21
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*	[Patch 2/4] Network rework: packet writing, sending and cleanups	Loic Blot	2015-02-16
	NetworkPacket.cpp: * Remove some deprecated functions, we must use streaming interface * m_data converted from u8* to std::vector<u8> * Add an exporter to forge packet to Connection object * implement operator << std::wstring. n * implement operator << std::string * dynamic resize when write packet content. * fix string writing and performances. * create ServerCommandFactory, used by client to get useful informations about packet processing (sending). * Reliability * Transmit channel * Implement putRawString for some ugly char (_INIT packet), and use it. * Many packet read and write migrated * Implement oldForgePacket to interface writing with current connection * fix U8/char/bool writing * fix string writing and performances. * add some missing functions * Use v3s16 read instead of reading x,y,z separately * Add irr::video::SColor support into packets * Add some missing handlers * Add a template function to increase offset * Throw a serialization error on packet reading (must be improved) PacketFactories: * Create ServerCommandFactory, used by client to get useful informations about packet processing (sending). * Create ClientCommandFactory, used by server to get useful informations about packet processing (sending). Client.cpp: * implement NetworkPacket ::Send interface. * Move packet handlers to a dedicated file * Remove Client::Send(SharedBuffer) Server.cpp: * implement NetworkPacket ::Send interface. * Rewrite all packets using NetworkPacket * Move packet handlers to a dedicated file * Remove Server::Send(SharedBuffer) ClientIface.cpp: * Remove sendToAll(SharedBuffer<u8>) Connection.hpp rework: * Remove duplicate include * Remove duplicate negation * Remove a useless variable * Improve code performance by using a m_peers_list instead of scanning m_peers map * Remove Connection::Send(SharedBuffer) * Fix useafterfree into NetworkPacket Sending * Remove unused Connection::sendToAll Test.cpp: * Remove dead code * Update tests to use NetworkPackets Misc: * add new wrappers to Send packets in client, using NetworkPacket * Add NetworkPacket methods for Connection * coding style fix * dead code since changes cleanup * Use v3s16 read instead of reading x,y,z separately in some packets * Use different files to handle packets received by client and server * Cleanup: Remove useless includes ok @Zeno- Tested by @Zeno- @VanessaE and @nerzhul on running servers

generated by cgit v1.2.3 (git 2.39.1) at 2025-02-08 11:53:29 +0000

/*
Minetest
Copyright (C) 2015 nerzhul, Loic Blot <loic.blot@unix-experience.fr>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include <chatmessage.h>
#include "server.h"
#include "log.h"

#include "content_sao.h"
#include "emerge.h"
#include "mapblock.h"
#include "nodedef.h"
#include "player.h"
#include "rollback_interface.h"
#include "scripting_server.h"
#include "settings.h"
#include "tool.h"
#include "version.h"
#include "network/networkprotocol.h"
#include "network/serveropcodes.h"
#include "util/auth.h"
#include "util/base64.h"
#include "util/pointedthing.h"
#include "util/serialize.h"
#include "util/srp.h"

void Server::handleCommand_Deprecated(NetworkPacket* pkt)
{
	infostream << "Server: " << toServerCommandTable[pkt->getCommand()].name
		<< " not supported anymore" << std::endl;
}

void Server::handleCommand_Init(NetworkPacket* pkt)
{

	if(pkt->getSize() < 1)
		return;

	RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);

	std::string addr_s;
	try {
		Address address = getPeerAddress(pkt->getPeerId());
		addr_s = address.serializeString();
	}
	catch (con::PeerNotFoundException &e) {
		/*
		 * no peer for this packet found
		 * most common reason is peer timeout, e.g. peer didn't
		 * respond for some time, your server was overloaded or
		 * things like that.
		 */
		infostream << "Server::ProcessData(): Canceling: peer "
				<< pkt->getPeerId() << " not found" << std::endl;
		return;
	}

	// If net_proto_version is set, this client has already been handled
	if (client->getState() > CS_Created) {
		verbosestream << "Server: Ignoring multiple TOSERVER_INITs from "
				<< addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
		return;
	}

	verbosestream << "Server: Got TOSERVER_INIT from " << addr_s << " (peer_id="
			<< pkt->getPeerId() << ")" << std::endl;

	// Do not allow multiple players in simple singleplayer mode.
	// This isn't a perfect way to do it, but will suffice for now
	if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
		infostream << "Server: Not allowing another client (" << addr_s
				<< ") to connect in simple singleplayer mode" << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SINGLEPLAYER);
		return;
	}

	// First byte after command is maximum supported
	// serialization version
	u8 client_max;
	u16 supp_compr_modes;
	u16 min_net_proto_version = 0;
	u16 max_net_proto_version;
	std::string playerName;

	*pkt >> client_max >> supp_compr_modes >> min_net_proto_version
			>> max_net_proto_version >> playerName;

	u8 our_max = SER_FMT_VER_HIGHEST_READ;
	// Use the highest version supported by both
	u8 depl_serial_v = std::min(client_max, our_max);
	// If it's lower than the lowest supported, give up.
	if (depl_serial_v < SER_FMT_VER_LOWEST_READ)
		depl_serial_v = SER_FMT_VER_INVALID;

	if (depl_serial_v == SER_FMT_VER_INVALID) {
		actionstream << "Server: A mismatched client tried to connect from "
				<< addr_s << std::endl;
		infostream<<"Server: Cannot negotiate serialization version with "
				<< addr_s << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_VERSION);
		return;
	}

	client->setPendingSerializationVersion(depl_serial_v);

	/*
		Read and check network protocol version
	*/

	u16 net_proto_version = 0;

	// Figure out a working version if it is possible at all
	if (max_net_proto_version >= SERVER_PROTOCOL_VERSION_MIN ||
			min_net_proto_version <= SERVER_PROTOCOL_VERSION_MAX) {
		// If maximum is larger than our maximum, go with our maximum
		if (max_net_proto_version > SERVER_PROTOCOL_VERSION_MAX)
			net_proto_version = SERVER_PROTOCOL_VERSION_MAX;
		// Else go with client's maximum
		else
			net_proto_version = max_net_proto_version;
	}

	verbosestream << "Server: " << addr_s << ": Protocol version: min: "
			<< min_net_proto_version << ", max: " << max_net_proto_version
			<< ", chosen: " << net_proto_version << std::endl;

	client->net_proto_version = net_proto_version;

	// On this handler at least protocol version 25 is required
	if (net_proto_version < 25 ||
			net_proto_version < SERVER_PROTOCOL_VERSION_MIN ||
			net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
		actionstream << "Server: A mismatched client tried to connect from "
				<< addr_s << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_VERSION);
		return;
	}

	if (g_settings->getBool("strict_protocol_version_checking")) {
		if (net_proto_version != LATEST_PROTOCOL_VERSION) {
			actionstream << "Server: A mismatched (strict) client tried to "
					<< "connect from " << addr_s << std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_VERSION);
			return;
		}
	}

	/*
		Validate player name
	*/
	const char* playername = playerName.c_str();

	size_t pns = playerName.size();
	if (pns == 0 || pns > PLAYERNAME_SIZE) {
		actionstream << "Server: Player with "
			<< ((pns > PLAYERNAME_SIZE) ? "a too long" : "an empty")
			<< " name tried to connect from " << addr_s << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_NAME);
		return;
	}

	if (string_allowed(playerName, PLAYERNAME_ALLOWED_CHARS) == false) {
		actionstream << "Server: Player with an invalid name "
				<< "tried to connect from " << addr_s << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_CHARS_IN_NAME);
		return;
	}

	m_clients.setPlayerName(pkt->getPeerId(), playername);
	//TODO (later) case insensitivity

	std::string legacyPlayerNameCasing = playerName;

	if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
		actionstream << "Server: Player with the name \"singleplayer\" "
				<< "tried to connect from " << addr_s << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_NAME);
		return;
	}

	{
		std::string reason;
		if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
			actionstream << "Server: Player with the name \"" << playerName << "\" "
					<< "tried to connect from " << addr_s << " "
					<< "but it was disallowed for the following reason: "
					<< reason << std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_CUSTOM_STRING,
					reason.c_str());
			return;
		}
	}

	infostream << "Server: New connection: \"" << playerName << "\" from "
			<< addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;

	// Enforce user limit.
	// Don't enforce for users that have some admin right
	if (m_clients.getClientIDs(CS_Created).size() >= g_settings->getU16("max_users") &&
			!checkPriv(playername, "server") &&
			!checkPriv(playername, "ban") &&
			!checkPriv(playername, "privs") &&
			!checkPriv(playername, "password") &&
			playername != g_settings->get("name")) {
		actionstream << "Server: " << playername << " tried to join from "
				<< addr_s << ", but there" << " are already max_users="
				<< g_settings->getU16("max_users") << " players." << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_TOO_MANY_USERS);
		return;
	}

	/*
		Compose auth methods for answer
	*/
	std::string encpwd; // encrypted Password field for the user
	bool has_auth = m_script->getAuth(playername, &encpwd, NULL);
	u32 auth_mechs = 0;

	client->chosen_mech = AUTH_MECHANISM_NONE;

	if (has_auth) {
		std::vector<std::string> pwd_components = str_split(encpwd, '#');
		if (pwd_components.size() == 4) {
			if (pwd_components[1] == "1") { // 1 means srp
				auth_mechs |= AUTH_MECHANISM_SRP;
				client->enc_pwd = encpwd;
			} else {
				actionstream << "User " << playername
					<< " tried to log in, but password field"
					<< " was invalid (unknown mechcode)." << std::endl;
				DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
				return;
			}
		} else if (base64_is_valid(encpwd)) {
			auth_mechs |= AUTH_MECHANISM_LEGACY_PASSWORD;
			client->enc_pwd = encpwd;
		} else {
			actionstream << "User " << playername
				<< " tried to log in, but password field"
				<< " was invalid (invalid base64)." << std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
			return;
		}
	} else {
		std::string default_password = g_settings->get("default_password");
		if (default_password.length() == 0) {
			auth_mechs |= AUTH_MECHANISM_FIRST_SRP;
		} else {
			// Take care of default passwords.
			client->enc_pwd = get_encoded_srp_verifier(playerName, default_password);
			auth_mechs |= AUTH_MECHANISM_SRP;
			// Allocate player in db, but only on successful login.
			client->create_player_on_auth_success = true;
		}
	}

	/*
		Answer with a TOCLIENT_HELLO
	*/

	verbosestream << "Sending TOCLIENT_HELLO with auth method field: "
		<< auth_mechs << std::endl;

	NetworkPacket resp_pkt(TOCLIENT_HELLO, 1 + 4
		+ legacyPlayerNameCasing.size(), pkt->getPeerId());

	u16 depl_compress_mode = NETPROTO_COMPRESSION_NONE;
	resp_pkt << depl_serial_v << depl_compress_mode << net_proto_version
		<< auth_mechs << legacyPlayerNameCasing;

	Send(&resp_pkt);

	client->allowed_auth_mechs = auth_mechs;
	client->setDeployedCompressionMode(depl_compress_mode);

	m_clients.event(pkt->getPeerId(), CSE_Hello);
}

void Server::handleCommand_Init_Legacy(NetworkPacket* pkt)
{
	// [0] u8 SER_FMT_VER_HIGHEST_READ
	// [1] u8[20] player_name
	// [21] u8[28] password <--- can be sent without this, from old versions

	if (pkt->getSize() < 1+PLAYERNAME_SIZE)
		return;

	RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);

	std::string addr_s;
	try {
		Address address = getPeerAddress(pkt->getPeerId());
		addr_s = address.serializeString();
	}
	catch (con::PeerNotFoundException &e) {
		/*
		 * no peer for this packet found
		 * most common reason is peer timeout, e.g. peer didn't
		 * respond for some time, your server was overloaded or
		 * things like that.
		 */
		infostream << "Server::ProcessData(): Canceling: peer "
				<< pkt->getPeerId() << " not found" << std::endl;
		return;
	}

	// If net_proto_version is set, this client has already been handled
	if (client->getState() > CS_Created) {
		verbosestream << "Server: Ignoring multiple TOSERVER_INITs from "
				<< addr_s << " (peer_id=" << pkt->getPeerId() << ")" << std::endl;
		return;
	}

	verbosestream << "Server: Got TOSERVER_INIT_LEGACY from " << addr_s << " (peer_id="
			<< pkt->getPeerId() << ")" << std::endl;

	// Do not allow multiple players in simple singleplayer mode.
	// This isn't a perfect way to do it, but will suffice for now
	if (m_simple_singleplayer_mode && m_clients.getClientIDs().size() > 1) {
		infostream << "Server: Not allowing another client (" << addr_s
				<< ") to connect in simple singleplayer mode" << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Running in simple singleplayer mode.");
		return;
	}

	// First byte after command is maximum supported
	// serialization version
	u8 client_max;

	*pkt >> client_max;

	u8 our_max = SER_FMT_VER_HIGHEST_READ;
	// Use the highest version supported by both
	int deployed = std::min(client_max, our_max);
	// If it's lower than the lowest supported, give up.
	if (deployed < SER_FMT_VER_LOWEST_READ)
		deployed = SER_FMT_VER_INVALID;

	if (deployed == SER_FMT_VER_INVALID) {
		actionstream << "Server: A mismatched client tried to connect from "
				<< addr_s << std::endl;
		infostream<<"Server: Cannot negotiate serialization version with "
				<< addr_s << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
				L"Your client's version is not supported.\n"
				L"Server version is ")
				+ utf8_to_wide(g_version_string) + L"."
		);
		return;
	}

	client->setPendingSerializationVersion(deployed);

	/*
		Read and check network protocol version
	*/

	u16 min_net_proto_version = 0;
	if (pkt->getSize() >= 1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2)
		min_net_proto_version = pkt->getU16(1 + PLAYERNAME_SIZE + PASSWORD_SIZE);

	// Use same version as minimum and maximum if maximum version field
	// doesn't exist (backwards compatibility)
	u16 max_net_proto_version = min_net_proto_version;
	if (pkt->getSize() >= 1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2 + 2)
		max_net_proto_version = pkt->getU16(1 + PLAYERNAME_SIZE + PASSWORD_SIZE + 2);

	// Start with client's maximum version
	u16 net_proto_version = max_net_proto_version;

	// Figure out a working version if it is possible at all
	if (max_net_proto_version >= SERVER_PROTOCOL_VERSION_MIN ||
			min_net_proto_version <= SERVER_PROTOCOL_VERSION_MAX) {
		// If maximum is larger than our maximum, go with our maximum
		if (max_net_proto_version > SERVER_PROTOCOL_VERSION_MAX)
			net_proto_version = SERVER_PROTOCOL_VERSION_MAX;
		// Else go with client's maximum
		else
			net_proto_version = max_net_proto_version;
	}

	// The client will send up to date init packet, ignore this one
	if (net_proto_version >= 25)
		return;

	verbosestream << "Server: " << addr_s << ": Protocol version: min: "
			<< min_net_proto_version << ", max: " << max_net_proto_version
			<< ", chosen: " << net_proto_version << std::endl;

	client->net_proto_version = net_proto_version;

	if (net_proto_version < SERVER_PROTOCOL_VERSION_MIN ||
			net_proto_version > SERVER_PROTOCOL_VERSION_MAX) {
		actionstream << "Server: A mismatched client tried to connect from "
				<< addr_s << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
				L"Your client's version is not supported.\n"
				L"Server version is ")
				+ utf8_to_wide(g_version_string) + L",\n"
				+ L"server's PROTOCOL_VERSION is "
				+ utf8_to_wide(itos(SERVER_PROTOCOL_VERSION_MIN))
				+ L"..."
				+ utf8_to_wide(itos(SERVER_PROTOCOL_VERSION_MAX))
				+ L", client's PROTOCOL_VERSION is "
				+ utf8_to_wide(itos(min_net_proto_version))
				+ L"..."
				+ utf8_to_wide(itos(max_net_proto_version))
		);
		return;
	}

	if (g_settings->getBool("strict_protocol_version_checking")) {
		if (net_proto_version != LATEST_PROTOCOL_VERSION) {
			actionstream << "Server: A mismatched (strict) client tried to "
					<< "connect from " << addr_s << std::endl;
			DenyAccess_Legacy(pkt->getPeerId(), std::wstring(
					L"Your client's version is not supported.\n"
					L"Server version is ")
					+ utf8_to_wide(g_version_string) + L",\n"
					+ L"server's PROTOCOL_VERSION (strict) is "
					+ utf8_to_wide(itos(LATEST_PROTOCOL_VERSION))
					+ L", client's PROTOCOL_VERSION is "
					+ utf8_to_wide(itos(min_net_proto_version))
					+ L"..."
					+ utf8_to_wide(itos(max_net_proto_version))
			);
			return;
		}
	}

	/*
		Set up player
	*/
	char playername[PLAYERNAME_SIZE];
	unsigned int playername_length = 0;
	for (; playername_length < PLAYERNAME_SIZE; playername_length++ ) {
		playername[playername_length] = pkt->getChar(1+playername_length);
		if (pkt->getChar(1+playername_length) == 0)
			break;
	}

	if (playername_length == PLAYERNAME_SIZE) {
		actionstream << "Server: Player with name exceeding max length "
				<< "tried to connect from " << addr_s << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Name too long");
		return;
	}


	if (playername[0]=='\0') {
		actionstream << "Server: Player with an empty name "
				<< "tried to connect from " << addr_s << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Empty name");
		return;
	}

	if (string_allowed(playername, PLAYERNAME_ALLOWED_CHARS) == false) {
		actionstream << "Server: Player with an invalid name "
				<< "tried to connect from " << addr_s << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Name contains unallowed characters");
		return;
	}

	if (!isSingleplayer() && strcasecmp(playername, "singleplayer") == 0) {
		actionstream << "Server: Player with the name \"singleplayer\" "
				<< "tried to connect from " << addr_s << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Name is not allowed");
		return;
	}

	{
		std::string reason;
		if (m_script->on_prejoinplayer(playername, addr_s, &reason)) {
			actionstream << "Server: Player with the name \"" << playername << "\" "
					<< "tried to connect from " << addr_s << " "
					<< "but it was disallowed for the following reason: "
					<< reason << std::endl;
			DenyAccess_Legacy(pkt->getPeerId(), utf8_to_wide(reason.c_str()));
			return;
		}
	}

	infostream<<"Server: New connection: \""<<playername<<"\" from "
			<<addr_s<<" (peer_id="<<pkt->getPeerId()<<")"<<std::endl;

	// Get password
	char given_password[PASSWORD_SIZE];
	if (pkt->getSize() < 1 + PLAYERNAME_SIZE + PASSWORD_SIZE) {
		// old version - assume blank password
		given_password[0] = 0;
	}
	else {
		for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
			given_password[i] = pkt->getChar(21 + i);
		}
		given_password[PASSWORD_SIZE - 1] = 0;
	}

	if (!base64_is_valid(given_password)) {
		actionstream << "Server: " << playername
				<< " supplied invalid password hash" << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Invalid password hash");
		return;
	}

	// Enforce user limit.
	// Don't enforce for users that have some admin right
	if (m_clients.getClientIDs(CS_Created).size() >= g_settings->getU16("max_users") &&
			!checkPriv(playername, "server") &&
			!checkPriv(playername, "ban") &&
			!checkPriv(playername, "privs") &&
			!checkPriv(playername, "password") &&
			playername != g_settings->get("name")) {
		actionstream << "Server: " << playername << " tried to join, but there"
				<< " are already max_users="
				<< g_settings->getU16("max_users") << " players." << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Too many users.");
		return;
	}

	std::string checkpwd; // Password hash to check against
	bool has_auth = m_script->getAuth(playername, &checkpwd, NULL);

	// If no authentication info exists for user, create it
	if (!has_auth) {
		if (!isSingleplayer() &&
				g_settings->getBool("disallow_empty_password") &&
				std::string(given_password) == "") {
			actionstream << "Server: " << playername
					<< " supplied empty password" << std::endl;
			DenyAccess_Legacy(pkt->getPeerId(), L"Empty passwords are "
					L"disallowed. Set a password and try again.");
			return;
		}
		std::string raw_default_password =
			g_settings->get("default_password");
		std::string initial_password =
			translate_password(playername, raw_default_password);

		// If default_password is empty, allow any initial password
		if (raw_default_password.length() == 0)
			initial_password = given_password;

		m_script->createAuth(playername, initial_password);
	}

	has_auth = m_script->getAuth(playername, &checkpwd, NULL);

	if (!has_auth) {
		actionstream << "Server: " << playername << " cannot be authenticated"
				<< " (auth handler does not work?)" << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Not allowed to login");
		return;
	}

	if (given_password != checkpwd) {
		actionstream << "Server: User " << playername
			<< " at " << addr_s
			<< " supplied wrong password (auth mechanism: legacy)."
			<< std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Wrong password");
		return;
	}

	RemotePlayer *player =
			static_cast<RemotePlayer*>(m_env->getPlayer(playername));

	if (player && player->peer_id != 0) {
		actionstream << "Server: " << playername << ": Failed to emerge player"
				<< " (player allocated to an another client)" << std::endl;
		DenyAccess_Legacy(pkt->getPeerId(), L"Another client is connected with this "
				L"name. If your client closed unexpectedly, try again in "
				L"a minute.");
	}

	m_clients.setPlayerName(pkt->getPeerId(), playername);

	/*
		Answer with a TOCLIENT_INIT
	*/

	NetworkPacket resp_pkt(TOCLIENT_INIT_LEGACY, 1 + 6 + 8 + 4,
			pkt->getPeerId());

	resp_pkt << (u8) deployed << (v3s16) floatToInt(v3f(0,0,0), BS)
			<< (u64) m_env->getServerMap().getSeed()
			<< g_settings->getFloat("dedicated_server_step");

	Send(&resp_pkt);
	m_clients.event(pkt->getPeerId(), CSE_InitLegacy);
}

void Server::handleCommand_Init2(NetworkPacket* pkt)
{
	verbosestream << "Server: Got TOSERVER_INIT2 from "
			<< pkt->getPeerId() << std::endl;

	m_clients.event(pkt->getPeerId(), CSE_GotInit2);
	u16 protocol_version = m_clients.getProtocolVersion(pkt->getPeerId());


	/*
		Send some initialization data
	*/

	infostream << "Server: Sending content to "
			<< getPlayerName(pkt->getPeerId()) << std::endl;

	// Send player movement settings
	SendMovement(pkt->getPeerId());

	// Send item definitions
	SendItemDef(pkt->getPeerId(), m_itemdef, protocol_version);

	// Send node definitions
	SendNodeDef(pkt->getPeerId(), m_nodedef, protocol_version);

	m_clients.event(pkt->getPeerId(), CSE_SetDefinitionsSent);

	// Send media announcement
	sendMediaAnnouncement(pkt->getPeerId());

	// Send detached inventories
	sendDetachedInventories(pkt->getPeerId());

	// Send time of day
	u16 time = m_env->getTimeOfDay();
	float time_speed = g_settings->getFloat("time_speed");
	SendTimeOfDay(pkt->getPeerId(), time, time_speed);

	SendCSMFlavourLimits(pkt->getPeerId());

	// Warnings about protocol version can be issued here
	if (getClient(pkt->getPeerId())->net_proto_version < LATEST_PROTOCOL_VERSION) {
		SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
				L"# Server: WARNING: YOUR CLIENT'S VERSION MAY NOT BE FULLY COMPATIBLE "
				L"WITH THIS SERVER!"));

	}
}

void Server::handleCommand_RequestMedia(NetworkPacket* pkt)
{
	std::vector<std::string> tosend;
	u16 numfiles;

	*pkt >> numfiles;

	infostream << "Sending " << numfiles << " files to "
			<< getPlayerName(pkt->getPeerId()) << std::endl;
	verbosestream << "TOSERVER_REQUEST_MEDIA: " << std::endl;

	for (u16 i = 0; i < numfiles; i++) {
		std::string name;

		*pkt >> name;

		tosend.push_back(name);
		verbosestream << "TOSERVER_REQUEST_MEDIA: requested file "
				<< name << std::endl;
	}

	sendRequestedMedia(pkt->getPeerId(), tosend);
}

void Server::handleCommand_ClientReady(NetworkPacket* pkt)
{
	u16 peer_id = pkt->getPeerId();

	PlayerSAO* playersao = StageTwoClientInit(peer_id);

	if (playersao == NULL) {
		actionstream
			<< "TOSERVER_CLIENT_READY stage 2 client init failed for peer_id: "
			<< peer_id << std::endl;
		m_con.DisconnectPeer(peer_id);
		return;
	}


	if (pkt->getSize() < 8) {
		errorstream
			<< "TOSERVER_CLIENT_READY client sent inconsistent data, disconnecting peer_id: "
			<< peer_id << std::endl;
		m_con.DisconnectPeer(peer_id);
		return;
	}

	u8 major_ver, minor_ver, patch_ver, reserved;
	std::string full_ver;
	*pkt >> major_ver >> minor_ver >> patch_ver >> reserved >> full_ver;

	m_clients.setClientVersion(
			peer_id, major_ver, minor_ver, patch_ver,
			full_ver);

	const std::vector<std::string> &players = m_clients.getPlayerNames();
	NetworkPacket list_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, peer_id);
	list_pkt << (u8) PLAYER_LIST_INIT << (u16) players.size();
	for (const std::string &player: players) {
		list_pkt <<  player;
	}
	m_clients.send(peer_id, 0, &list_pkt, true);

	NetworkPacket notice_pkt(TOCLIENT_UPDATE_PLAYER_LIST, 0, PEER_ID_INEXISTENT);
	// (u16) 1 + std::string represents a pseudo vector serialization representation
	notice_pkt << (u8) PLAYER_LIST_ADD << (u16) 1 << std::string(playersao->getPlayer()->getName());
	m_clients.sendToAll(&notice_pkt);

	m_clients.event(peer_id, CSE_SetClientReady);
	m_script->on_joinplayer(playersao);
	// Send shutdown timer if shutdown has been scheduled
	if (m_shutdown_timer > 0.0f) {
		std::wstringstream ws;
		ws << L"*** Server shutting down in "
				<< duration_to_string(myround(m_shutdown_timer)).c_str() << ".";
		SendChatMessage(pkt->getPeerId(), ws.str());
	}
}

void Server::handleCommand_GotBlocks(NetworkPacket* pkt)
{
	if (pkt->getSize() < 1)
		return;

	/*
		[0] u16 command
		[2] u8 count
		[3] v3s16 pos_0
		[3+6] v3s16 pos_1
		...
	*/

	u8 count;
	*pkt >> count;

	RemoteClient *client = getClient(pkt->getPeerId());

	if ((s16)pkt->getSize() < 1 + (int)count * 6) {
		throw con::InvalidIncomingDataException
				("GOTBLOCKS length is too short");
	}

	for (u16 i = 0; i < count; i++) {
		v3s16 p;
		*pkt >> p;
		client->GotBlock(p);
	}
}

void Server::process_PlayerPos(RemotePlayer *player, PlayerSAO *playersao,
	NetworkPacket *pkt)
{
	if (pkt->getRemainingBytes() < 12 + 12 + 4 + 4)
		return;

	v3s32 ps, ss;
	s32 f32pitch, f32yaw;
	u8 f32fov;

	*pkt >> ps;
	*pkt >> ss;
	*pkt >> f32pitch;
	*pkt >> f32yaw;

	f32 pitch = (f32)f32pitch / 100.0;
	f32 yaw = (f32)f32yaw / 100.0;
	u32 keyPressed = 0;

	// default behavior (in case an old client doesn't send these)
	f32 fov = 0;
	u8 wanted_range = 0;

	if (pkt->getRemainingBytes() >= 4)
		*pkt >> keyPressed;
	if (pkt->getRemainingBytes() >= 1) {
		*pkt >> f32fov;
		fov = (f32)f32fov / 80.0;
	}
	if (pkt->getRemainingBytes() >= 1)
		*pkt >> wanted_range;

	v3f position((f32)ps.X / 100.0, (f32)ps.Y / 100.0, (f32)ps.Z / 100.0);
	v3f speed((f32)ss.X / 100.0, (f32)ss.Y / 100.0, (f32)ss.Z / 100.0);

	pitch = modulo360f(pitch);
	yaw = wrapDegrees_0_360(yaw);

	playersao->setBasePosition(position);
	player->setSpeed(speed);
	playersao->setPitch(pitch);
	playersao->setYaw(yaw);
	playersao->setFov(fov);
	playersao->setWantedRange(wanted_range);
	player->keyPressed = keyPressed;
	player->control.up = (keyPressed & 1);
	player->control.down = (keyPressed & 2);
	player->control.left = (keyPressed & 4);
	player->control.right = (keyPressed & 8);
	player->control.jump = (keyPressed & 16);
	player->control.aux1 = (keyPressed & 32);
	player->control.sneak = (keyPressed & 64);
	player->control.LMB = (keyPressed & 128);
	player->control.RMB = (keyPressed & 256);

	if (playersao->checkMovementCheat()) {
		// Call callbacks
		m_script->on_cheat(playersao, "moved_too_fast");
		SendMovePlayer(pkt->getPeerId());
	}
}

void Server::handleCommand_PlayerPos(NetworkPacket* pkt)
{
	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	if (playersao == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player object for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	// If player is dead we don't care of this packet
	if (playersao->isDead()) {
		verbosestream << "TOSERVER_PLAYERPOS: " << player->getName()
				<< " is dead. Ignoring packet";
		return;
	}

	process_PlayerPos(player, playersao, pkt);
}

void Server::handleCommand_DeletedBlocks(NetworkPacket* pkt)
{
	if (pkt->getSize() < 1)
		return;

	/*
		[0] u16 command
		[2] u8 count
		[3] v3s16 pos_0
		[3+6] v3s16 pos_1
		...
	*/

	u8 count;
	*pkt >> count;

	RemoteClient *client = getClient(pkt->getPeerId());

	if ((s16)pkt->getSize() < 1 + (int)count * 6) {
		throw con::InvalidIncomingDataException
				("DELETEDBLOCKS length is too short");
	}

	for (u16 i = 0; i < count; i++) {
		v3s16 p;
		*pkt >> p;
		client->SetBlockNotSent(p);
	}
}

void Server::handleCommand_InventoryAction(NetworkPacket* pkt)
{
	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());

	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	if (playersao == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player object for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	// Strip command and create a stream
	std::string datastring(pkt->getString(0), pkt->getSize());
	verbosestream << "TOSERVER_INVENTORY_ACTION: data=" << datastring
		<< std::endl;
	std::istringstream is(datastring, std::ios_base::binary);
	// Create an action
	InventoryAction *a = InventoryAction::deSerialize(is);
	if (!a) {
		infostream << "TOSERVER_INVENTORY_ACTION: "
				<< "InventoryAction::deSerialize() returned NULL"
				<< std::endl;
		return;
	}

	// If something goes wrong, this player is to blame
	RollbackScopeActor rollback_scope(m_rollback,
			std::string("player:")+player->getName());

	/*
		Note: Always set inventory not sent, to repair cases
		where the client made a bad prediction.
	*/

	/*
		Handle restrictions and special cases of the move action
	*/
	if (a->getType() == IAction::Move) {
		IMoveAction *ma = (IMoveAction*)a;

		ma->from_inv.applyCurrentPlayer(player->getName());
		ma->to_inv.applyCurrentPlayer(player->getName());

		setInventoryModified(ma->from_inv, false);
		setInventoryModified(ma->to_inv, false);

		bool from_inv_is_current_player =
			(ma->from_inv.type == InventoryLocation::PLAYER) &&
			(ma->from_inv.name == player->getName());

		bool to_inv_is_current_player =
			(ma->to_inv.type == InventoryLocation::PLAYER) &&
			(ma->to_inv.name == player->getName());

		/*
			Disable moving items out of craftpreview
		*/
		if (ma->from_list == "craftpreview") {
			infostream << "Ignoring IMoveAction from "
					<< (ma->from_inv.dump()) << ":" << ma->from_list
					<< " to " << (ma->to_inv.dump()) << ":" << ma->to_list
					<< " because src is " << ma->from_list << std::endl;
			delete a;
			return;
		}

		/*
			Disable moving items into craftresult and craftpreview
		*/
		if (ma->to_list == "craftpreview" || ma->to_list == "craftresult") {
			infostream << "Ignoring IMoveAction from "
					<< (ma->from_inv.dump()) << ":" << ma->from_list
					<< " to " << (ma->to_inv.dump()) << ":" << ma->to_list
					<< " because dst is " << ma->to_list << std::endl;
			delete a;
			return;
		}

		// Disallow moving items in elsewhere than player's inventory
		// if not allowed to interact
		if (!checkPriv(player->getName(), "interact") &&
				(!from_inv_is_current_player ||
				!to_inv_is_current_player)) {
			infostream << "Cannot move outside of player's inventory: "
					<< "No interact privilege" << std::endl;
			delete a;
			return;
		}
	}
	/*
		Handle restrictions and special cases of the drop action
	*/
	else if (a->getType() == IAction::Drop) {
		IDropAction *da = (IDropAction*)a;

		da->from_inv.applyCurrentPlayer(player->getName());

		setInventoryModified(da->from_inv, false);

		/*
			Disable dropping items out of craftpreview
		*/
		if (da->from_list == "craftpreview") {
			infostream << "Ignoring IDropAction from "
					<< (da->from_inv.dump()) << ":" << da->from_list
					<< " because src is " << da->from_list << std::endl;
			delete a;
			return;
		}

		// Disallow dropping items if not allowed to interact
		if (!checkPriv(player->getName(), "interact")) {
			delete a;
			return;
		}

		// Disallow dropping items if dead
		if (playersao->isDead()) {
			infostream << "Ignoring IDropAction from "
					<< (da->from_inv.dump()) << ":" << da->from_list
					<< " because player is dead." << std::endl;
			delete a;
			return;
		}
	}
	/*
		Handle restrictions and special cases of the craft action
	*/
	else if (a->getType() == IAction::Craft) {
		ICraftAction *ca = (ICraftAction*)a;

		ca->craft_inv.applyCurrentPlayer(player->getName());

		setInventoryModified(ca->craft_inv, false);

		//bool craft_inv_is_current_player =
		//	(ca->craft_inv.type == InventoryLocation::PLAYER) &&
		//	(ca->craft_inv.name == player->getName());

		// Disallow crafting if not allowed to interact
		if (!checkPriv(player->getName(), "interact")) {
			infostream << "Cannot craft: "
					<< "No interact privilege" << std::endl;
			delete a;
			return;
		}
	}

	// Do the action
	a->apply(this, playersao, this);
	// Eat the action
	delete a;

	SendInventory(playersao);
}

void Server::handleCommand_ChatMessage(NetworkPacket* pkt)
{
	/*
		u16 command
		u16 length
		wstring message
	*/
	u16 len;
	*pkt >> len;

	std::wstring message;
	for (u16 i = 0; i < len; i++) {
		u16 tmp_wchar;
		*pkt >> tmp_wchar;

		message += (wchar_t)tmp_wchar;
	}

	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	// Get player name of this client
	std::string name = player->getName();
	std::wstring wname = narrow_to_wide(name);

	std::wstring answer_to_sender = handleChat(name, wname, message, true, player);
	if (!answer_to_sender.empty()) {
		// Send the answer to sender
		SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_NORMAL,
				answer_to_sender, wname));
	}
}

void Server::handleCommand_Damage(NetworkPacket* pkt)
{
	u8 damage;

	*pkt >> damage;

	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());

	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	if (playersao == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player object for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	if (g_settings->getBool("enable_damage")) {
		if (playersao->isDead()) {
			verbosestream << "Server::ProcessData(): Info: "
				"Ignoring damage as player " << player->getName()
				<< " is already dead." << std::endl;
			return;
		}

		actionstream << player->getName() << " damaged by "
				<< (int)damage << " hp at " << PP(playersao->getBasePosition() / BS)
				<< std::endl;

		playersao->setHP(playersao->getHP() - damage);
		SendPlayerHPOrDie(playersao);
	}
}

void Server::handleCommand_Password(NetworkPacket* pkt)
{
	if (pkt->getSize() != PASSWORD_SIZE * 2)
		return;

	std::string oldpwd;
	std::string newpwd;

	// Deny for clients using the new protocol
	RemoteClient* client = getClient(pkt->getPeerId(), CS_Created);
	if (client->net_proto_version >= 25) {
		infostream << "Server::handleCommand_Password(): Denying change: "
			<< " Client protocol version for peer_id=" << pkt->getPeerId()
			<< " too new!" << std::endl;
		return;
	}

	for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
		char c = pkt->getChar(i);
		if (c == 0)
			break;
		oldpwd += c;
	}

	for (u16 i = 0; i < PASSWORD_SIZE - 1; i++) {
		char c = pkt->getChar(PASSWORD_SIZE + i);
		if (c == 0)
			break;
		newpwd += c;
	}

	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	if (!base64_is_valid(newpwd)) {
		infostream<<"Server: " << player->getName() <<
				" supplied invalid password hash" << std::endl;
		// Wrong old password supplied!!
		SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
				L"Invalid new password hash supplied. Password NOT changed."));
		return;
	}

	infostream << "Server: Client requests a password change from "
			<< "'" << oldpwd << "' to '" << newpwd << "'" << std::endl;

	std::string playername = player->getName();

	std::string checkpwd;
	m_script->getAuth(playername, &checkpwd, NULL);

	if (oldpwd != checkpwd) {
		infostream << "Server: invalid old password" << std::endl;
		// Wrong old password supplied!!
		SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
				L"Invalid old password supplied. Password NOT changed."));
		return;
	}

	bool success = m_script->setPassword(playername, newpwd);
	if (success) {
		actionstream << player->getName() << " changes password" << std::endl;
		SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
				L"Password change successful."));
	} else {
		actionstream << player->getName() << " tries to change password but "
				<< "it fails" << std::endl;
		SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
				L"Password change failed or unavailable."));
	}
}

void Server::handleCommand_PlayerItem(NetworkPacket* pkt)
{
	if (pkt->getSize() < 2)
		return;

	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());

	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	if (playersao == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player object for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	u16 item;

	*pkt >> item;

	playersao->setWieldIndex(item);
}

void Server::handleCommand_Respawn(NetworkPacket* pkt)
{
	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());
	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	assert(playersao);

	if (!playersao->isDead())
		return;

	RespawnPlayer(pkt->getPeerId());

	actionstream << player->getName() << " respawns at "
			<< PP(playersao->getBasePosition() / BS) << std::endl;

	// ActiveObject is added to environment in AsyncRunStep after
	// the previous addition has been successfully removed
}

void Server::handleCommand_Interact(NetworkPacket* pkt)
{
	/*
		[0] u16 command
		[2] u8 action
		[3] u16 item
		[5] u32 length of the next item (plen)
		[9] serialized PointedThing
		[9 + plen] player position information
		actions:
		0: start digging (from undersurface) or use
		1: stop digging (all parameters ignored)
		2: digging completed
		3: place block or item (to abovesurface)
		4: use item
		5: rightclick air ("activate")
	*/
	u8 action;
	u16 item_i;
	*pkt >> action;
	*pkt >> item_i;
	std::istringstream tmp_is(pkt->readLongString(), std::ios::binary);
	PointedThing pointed;
	pointed.deSerialize(tmp_is);

	verbosestream << "TOSERVER_INTERACT: action=" << (int)action << ", item="
			<< item_i << ", pointed=" << pointed.dump() << std::endl;

	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());

	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	if (playersao == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player object for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	if (playersao->isDead()) {
		actionstream << "Server: NoCheat: " << player->getName()
				<< " tried to interact while dead; ignoring." << std::endl;
		if (pointed.type == POINTEDTHING_NODE) {
			// Re-send block to revert change on client-side
			RemoteClient *client = getClient(pkt->getPeerId());
			v3s16 blockpos = getNodeBlockPos(pointed.node_undersurface);
			client->SetBlockNotSent(blockpos);
		}
		// Call callbacks
		m_script->on_cheat(playersao, "interacted_while_dead");
		return;
	}

	process_PlayerPos(player, playersao, pkt);

	v3f player_pos = playersao->getLastGoodPosition();

	// Update wielded item
	playersao->setWieldIndex(item_i);

	// Get pointed to node (undefined if not POINTEDTYPE_NODE)
	v3s16 p_under = pointed.node_undersurface;
	v3s16 p_above = pointed.node_abovesurface;

	// Get pointed to object (NULL if not POINTEDTYPE_OBJECT)
	ServerActiveObject *pointed_object = NULL;
	if (pointed.type == POINTEDTHING_OBJECT) {
		pointed_object = m_env->getActiveObject(pointed.object_id);
		if (pointed_object == NULL) {
			verbosestream << "TOSERVER_INTERACT: "
				"pointed object is NULL" << std::endl;
			return;
		}

	}

	v3f pointed_pos_under = player_pos;
	v3f pointed_pos_above = player_pos;
	if (pointed.type == POINTEDTHING_NODE) {
		pointed_pos_under = intToFloat(p_under, BS);
		pointed_pos_above = intToFloat(p_above, BS);
	}
	else if (pointed.type == POINTEDTHING_OBJECT) {
		pointed_pos_under = pointed_object->getBasePosition();
		pointed_pos_above = pointed_pos_under;
	}

	/*
		Make sure the player is allowed to do it
	*/
	if (!checkPriv(player->getName(), "interact")) {
		actionstream<<player->getName()<<" attempted to interact with "
				<<pointed.dump()<<" without 'interact' privilege"
				<<std::endl;
		// Re-send block to revert change on client-side
		RemoteClient *client = getClient(pkt->getPeerId());
		// Digging completed -> under
		if (action == 2) {
			v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
			client->SetBlockNotSent(blockpos);
		}
		// Placement -> above
		if (action == 3) {
			v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
			client->SetBlockNotSent(blockpos);
		}
		return;
	}

	/*
		Check that target is reasonably close
		(only when digging or placing things)
	*/
	static thread_local const bool enable_anticheat =
			!g_settings->getBool("disable_anticheat");

	if ((action == 0 || action == 2 || action == 3 || action == 4) &&
			(enable_anticheat && !isSingleplayer())) {
		float d = player_pos.getDistanceFrom(pointed_pos_under);
		const ItemDefinition &playeritem_def =
			playersao->getWieldedItem().getDefinition(m_itemdef);
		float max_d = BS * playeritem_def.range;
		InventoryList *hlist = playersao->getInventory()->getList("hand");
		const ItemDefinition &hand_def =
			hlist ? (hlist->getItem(0).getDefinition(m_itemdef)) : (m_itemdef->get(""));
		float max_d_hand = BS * hand_def.range;
		if (max_d < 0 && max_d_hand >= 0)
			max_d = max_d_hand;
		else if (max_d < 0)
			max_d = BS * 4.0;
		// cube diagonal: sqrt(3) = 1.73
		if (d > max_d * 1.73) {
			actionstream << "Player " << player->getName()
					<< " tried to access " << pointed.dump()
					<< " from too far: "
					<< "d=" << d <<", max_d=" << max_d
					<< ". ignoring." << std::endl;
			// Re-send block to revert change on client-side
			RemoteClient *client = getClient(pkt->getPeerId());
			v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
			client->SetBlockNotSent(blockpos);
			// Call callbacks
			m_script->on_cheat(playersao, "interacted_too_far");
			// Do nothing else
			return;
		}
	}

	/*
		If something goes wrong, this player is to blame
	*/
	RollbackScopeActor rollback_scope(m_rollback,
			std::string("player:")+player->getName());

	/*
		0: start digging or punch object
	*/
	if (action == 0) {
		if (pointed.type == POINTEDTHING_NODE) {
			MapNode n(CONTENT_IGNORE);
			bool pos_ok;

			n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
			if (!pos_ok) {
				infostream << "Server: Not punching: Node not found."
						<< " Adding block to emerge queue."
						<< std::endl;
				m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
					getNodeBlockPos(p_above), false);
			}

			if (n.getContent() != CONTENT_IGNORE)
				m_script->node_on_punch(p_under, n, playersao, pointed);

			// Cheat prevention
			playersao->noCheatDigStart(p_under);
		}
		else if (pointed.type == POINTEDTHING_OBJECT) {
			// Skip if object has been removed
			if (pointed_object->m_removed)
				return;

			actionstream<<player->getName()<<" punches object "
					<<pointed.object_id<<": "
					<<pointed_object->getDescription()<<std::endl;

			ItemStack punchitem = playersao->getWieldedItemOrHand();
			ToolCapabilities toolcap =
					punchitem.getToolCapabilities(m_itemdef);
			v3f dir = (pointed_object->getBasePosition() -
					(playersao->getBasePosition() + playersao->getEyeOffset())
						).normalize();
			float time_from_last_punch =
				playersao->resetTimeFromLastPunch();

			s16 src_original_hp = pointed_object->getHP();
			s16 dst_origin_hp = playersao->getHP();

			pointed_object->punch(dir, &toolcap, playersao,
					time_from_last_punch);

			// If the object is a player and its HP changed
			if (src_original_hp != pointed_object->getHP() &&
					pointed_object->getType() == ACTIVEOBJECT_TYPE_PLAYER) {
				SendPlayerHPOrDie((PlayerSAO *)pointed_object);
			}

			// If the puncher is a player and its HP changed
			if (dst_origin_hp != playersao->getHP())
				SendPlayerHPOrDie(playersao);
		}

	} // action == 0

	/*
		1: stop digging
	*/
	else if (action == 1) {
	} // action == 1

	/*
		2: Digging completed
	*/
	else if (action == 2) {
		// Only digging of nodes
		if (pointed.type == POINTEDTHING_NODE) {
			bool pos_ok;
			MapNode n = m_env->getMap().getNodeNoEx(p_under, &pos_ok);
			if (!pos_ok) {
				infostream << "Server: Not finishing digging: Node not found."
						<< " Adding block to emerge queue."
						<< std::endl;
				m_emerge->enqueueBlockEmerge(pkt->getPeerId(),
					getNodeBlockPos(p_above), false);
			}

			/* Cheat prevention */
			bool is_valid_dig = true;
			if (enable_anticheat && !isSingleplayer()) {
				v3s16 nocheat_p = playersao->getNoCheatDigPos();
				float nocheat_t = playersao->getNoCheatDigTime();
				playersao->noCheatDigEnd();
				// If player didn't start digging this, ignore dig
				if (nocheat_p != p_under) {
					infostream << "Server: NoCheat: " << player->getName()
							<< " started digging "
							<< PP(nocheat_p) << " and completed digging "
							<< PP(p_under) << "; not digging." << std::endl;
					is_valid_dig = false;
					// Call callbacks
					m_script->on_cheat(playersao, "finished_unknown_dig");
				}
				// Get player's wielded item
				ItemStack playeritem = playersao->getWieldedItemOrHand();
				ToolCapabilities playeritem_toolcap =
						playeritem.getToolCapabilities(m_itemdef);
				// Get diggability and expected digging time
				DigParams params = getDigParams(m_nodedef->get(n).groups,
						&playeritem_toolcap);
				// If can't dig, try hand
				if (!params.diggable) {
					InventoryList *hlist = playersao->getInventory()->getList("hand");
					const ItemDefinition &hand =
						hlist ? hlist->getItem(0).getDefinition(m_itemdef) : m_itemdef->get("");
					const ToolCapabilities *tp = hand.tool_capabilities;
					if (tp)
						params = getDigParams(m_nodedef->get(n).groups, tp);
				}
				// If can't dig, ignore dig
				if (!params.diggable) {
					infostream << "Server: NoCheat: " << player->getName()
							<< " completed digging " << PP(p_under)
							<< ", which is not diggable with tool. not digging."
							<< std::endl;
					is_valid_dig = false;
					// Call callbacks
					m_script->on_cheat(playersao, "dug_unbreakable");
				}
				// Check digging time
				// If already invalidated, we don't have to
				if (!is_valid_dig) {
					// Well not our problem then
				}
				// Clean and long dig
				else if (params.time > 2.0 && nocheat_t * 1.2 > params.time) {
					// All is good, but grab time from pool; don't care if
					// it's actually available
					playersao->getDigPool().grab(params.time);
				}
				// Short or laggy dig
				// Try getting the time from pool
				else if (playersao->getDigPool().grab(params.time)) {
					// All is good
				}
				// Dig not possible
				else {
					infostream << "Server: NoCheat: " << player->getName()
							<< " completed digging " << PP(p_under)
							<< "too fast; not digging." << std::endl;
					is_valid_dig = false;
					// Call callbacks
					m_script->on_cheat(playersao, "dug_too_fast");
				}
			}

			/* Actually dig node */

			if (is_valid_dig && n.getContent() != CONTENT_IGNORE)
				m_script->node_on_dig(p_under, n, playersao);

			v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
			RemoteClient *client = getClient(pkt->getPeerId());
			// Send unusual result (that is, node not being removed)
			if (m_env->getMap().getNodeNoEx(p_under).getContent() != CONTENT_AIR) {
				// Re-send block to revert change on client-side
				client->SetBlockNotSent(blockpos);
			}
			else {
				client->ResendBlockIfOnWire(blockpos);
			}
		}
	} // action == 2

	/*
		3: place block or right-click object
	*/
	else if (action == 3) {
		ItemStack item = playersao->getWieldedItem();

		// Reset build time counter
		if (pointed.type == POINTEDTHING_NODE &&
				item.getDefinition(m_itemdef).type == ITEM_NODE)
			getClient(pkt->getPeerId())->m_time_from_building = 0.0;

		if (pointed.type == POINTEDTHING_OBJECT) {
			// Right click object

			// Skip if object has been removed
			if (pointed_object->m_removed)
				return;

			actionstream << player->getName() << " right-clicks object "
					<< pointed.object_id << ": "
					<< pointed_object->getDescription() << std::endl;

			// Do stuff
			pointed_object->rightClick(playersao);
		}
		else if (m_script->item_OnPlace(
				item, playersao, pointed)) {
			// Placement was handled in lua

			// Apply returned ItemStack
			if (playersao->setWieldedItem(item)) {
				SendInventory(playersao);
			}
		}

		// If item has node placement prediction, always send the
		// blocks to make sure the client knows what exactly happened
		RemoteClient *client = getClient(pkt->getPeerId());
		v3s16 blockpos = getNodeBlockPos(floatToInt(pointed_pos_above, BS));
		v3s16 blockpos2 = getNodeBlockPos(floatToInt(pointed_pos_under, BS));
		if (item.getDefinition(m_itemdef).node_placement_prediction != "") {
			client->SetBlockNotSent(blockpos);
			if (blockpos2 != blockpos) {
				client->SetBlockNotSent(blockpos2);
			}
		}
		else {
			client->ResendBlockIfOnWire(blockpos);
			if (blockpos2 != blockpos) {
				client->ResendBlockIfOnWire(blockpos2);
			}
		}
	} // action == 3

	/*
		4: use
	*/
	else if (action == 4) {
		ItemStack item = playersao->getWieldedItem();

		actionstream << player->getName() << " uses " << item.name
				<< ", pointing at " << pointed.dump() << std::endl;

		if (m_script->item_OnUse(
				item, playersao, pointed)) {
			// Apply returned ItemStack
			if (playersao->setWieldedItem(item)) {
				SendInventory(playersao);
			}
		}

	} // action == 4

	/*
		5: rightclick air
	*/
	else if (action == 5) {
		ItemStack item = playersao->getWieldedItem();

		actionstream << player->getName() << " activates "
				<< item.name << std::endl;

		if (m_script->item_OnSecondaryUse(
				item, playersao)) {
			if( playersao->setWieldedItem(item)) {
				SendInventory(playersao);
			}
		}
	}


	/*
		Catch invalid actions
	*/
	else {
		warningstream << "Server: Invalid action "
				<< action << std::endl;
	}
}

void Server::handleCommand_RemovedSounds(NetworkPacket* pkt)
{
	u16 num;
	*pkt >> num;
	for (u16 k = 0; k < num; k++) {
		s32 id;

		*pkt >> id;

		std::unordered_map<s32, ServerPlayingSound>::iterator i =
			m_playing_sounds.find(id);
		if (i == m_playing_sounds.end())
			continue;

		ServerPlayingSound &psound = i->second;
		psound.clients.erase(pkt->getPeerId());
		if (psound.clients.empty())
			m_playing_sounds.erase(i++);
	}
}

void Server::handleCommand_NodeMetaFields(NetworkPacket* pkt)
{
	v3s16 p;
	std::string formname;
	u16 num;

	*pkt >> p >> formname >> num;

	StringMap fields;
	for (u16 k = 0; k < num; k++) {
		std::string fieldname;
		*pkt >> fieldname;
		fields[fieldname] = pkt->readLongString();
	}

	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());

	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	if (playersao == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player object for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!"  << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	// If something goes wrong, this player is to blame
	RollbackScopeActor rollback_scope(m_rollback,
			std::string("player:")+player->getName());

	// Check the target node for rollback data; leave others unnoticed
	RollbackNode rn_old(&m_env->getMap(), p, this);

	m_script->node_on_receive_fields(p, formname, fields, playersao);

	// Report rollback data
	RollbackNode rn_new(&m_env->getMap(), p, this);
	if (rollback() && rn_new != rn_old) {
		RollbackAction action;
		action.setSetNode(p, rn_old, rn_new);
		rollback()->reportAction(action);
	}
}

void Server::handleCommand_InventoryFields(NetworkPacket* pkt)
{
	std::string formname;
	u16 num;

	*pkt >> formname >> num;

	StringMap fields;
	for (u16 k = 0; k < num; k++) {
		std::string fieldname;
		*pkt >> fieldname;
		fields[fieldname] = pkt->readLongString();
	}

	RemotePlayer *player = m_env->getPlayer(pkt->getPeerId());

	if (player == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	PlayerSAO *playersao = player->getPlayerSAO();
	if (playersao == NULL) {
		errorstream << "Server::ProcessData(): Canceling: "
				"No player object for peer_id=" << pkt->getPeerId()
				<< " disconnecting peer!" << std::endl;
		m_con.DisconnectPeer(pkt->getPeerId());
		return;
	}

	m_script->on_playerReceiveFields(playersao, formname, fields);
}

void Server::handleCommand_FirstSrp(NetworkPacket* pkt)
{
	RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
	ClientState cstate = client->getState();

	std::string playername = client->getName();

	std::string salt;
	std::string verification_key;

	std::string addr_s = getPeerAddress(pkt->getPeerId()).serializeString();
	u8 is_empty;

	*pkt >> salt >> verification_key >> is_empty;

	verbosestream << "Server: Got TOSERVER_FIRST_SRP from " << addr_s
		<< ", with is_empty=" << (is_empty == 1) << std::endl;

	// Either this packet is sent because the user is new or to change the password
	if (cstate == CS_HelloSent) {
		if (!client->isMechAllowed(AUTH_MECHANISM_FIRST_SRP)) {
			actionstream << "Server: Client from " << addr_s
					<< " tried to set password without being "
					<< "authenticated, or the username being new." << std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
			return;
		}

		if (!isSingleplayer() &&
				g_settings->getBool("disallow_empty_password") &&
				is_empty == 1) {
			actionstream << "Server: " << playername
					<< " supplied empty password from " << addr_s << std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_EMPTY_PASSWORD);
			return;
		}

		std::string initial_ver_key;

		initial_ver_key = encode_srp_verifier(verification_key, salt);
		m_script->createAuth(playername, initial_ver_key);

		acceptAuth(pkt->getPeerId(), false);
	} else {
		if (cstate < CS_SudoMode) {
			infostream << "Server::ProcessData(): Ignoring TOSERVER_FIRST_SRP from "
					<< addr_s << ": " << "Client has wrong state " << cstate << "."
					<< std::endl;
			return;
		}
		m_clients.event(pkt->getPeerId(), CSE_SudoLeave);
		std::string pw_db_field = encode_srp_verifier(verification_key, salt);
		bool success = m_script->setPassword(playername, pw_db_field);
		if (success) {
			actionstream << playername << " changes password" << std::endl;
			SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
					L"Password change successful."));
		} else {
			actionstream << playername << " tries to change password but "
				<< "it fails" << std::endl;
			SendChatMessage(pkt->getPeerId(), ChatMessage(CHATMESSAGE_TYPE_SYSTEM,
					L"Password change failed or unavailable."));
		}
	}
}

void Server::handleCommand_SrpBytesA(NetworkPacket* pkt)
{
	RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
	ClientState cstate = client->getState();

	bool wantSudo = (cstate == CS_Active);

	if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
		actionstream << "Server: got SRP _A packet in wrong state "
			<< cstate << " from "
			<< getPeerAddress(pkt->getPeerId()).serializeString()
			<< ". Ignoring." << std::endl;
		return;
	}

	if (client->chosen_mech != AUTH_MECHANISM_NONE) {
		actionstream << "Server: got SRP _A packet, while auth"
			<< "is already going on with mech " << client->chosen_mech
			<< " from " << getPeerAddress(pkt->getPeerId()).serializeString()
			<< " (wantSudo=" << wantSudo << "). Ignoring." << std::endl;
		if (wantSudo) {
			DenySudoAccess(pkt->getPeerId());
			return;
		} else {
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
			return;
		}
	}

	std::string bytes_A;
	u8 based_on;
	*pkt >> bytes_A >> based_on;

	infostream << "Server: TOSERVER_SRP_BYTES_A received with "
		<< "based_on=" << int(based_on) << " and len_A="
		<< bytes_A.length() << "." << std::endl;

	AuthMechanism chosen = (based_on == 0) ?
		AUTH_MECHANISM_LEGACY_PASSWORD : AUTH_MECHANISM_SRP;

	if (wantSudo) {
		if (!client->isSudoMechAllowed(chosen)) {
			actionstream << "Server: Player \"" << client->getName()
				<< "\" at " << getPeerAddress(pkt->getPeerId()).serializeString()
				<< " tried to change password using unallowed mech "
				<< chosen << "." << std::endl;
			DenySudoAccess(pkt->getPeerId());
			return;
		}
	} else {
		if (!client->isMechAllowed(chosen)) {
			actionstream << "Server: Client tried to authenticate from "
				<< getPeerAddress(pkt->getPeerId()).serializeString()
				<< " using unallowed mech " << chosen << "." << std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
			return;
		}
	}

	client->chosen_mech = chosen;

	std::string salt;
	std::string verifier;

	if (based_on == 0) {

		generate_srp_verifier_and_salt(client->getName(), client->enc_pwd,
			&verifier, &salt);
	} else if (!decode_srp_verifier_and_salt(client->enc_pwd, &verifier, &salt)) {
		// Non-base64 errors should have been catched in the init handler
		actionstream << "Server: User " << client->getName()
			<< " tried to log in, but srp verifier field"
			<< " was invalid (most likely invalid base64)." << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
		return;
	}

	char *bytes_B = 0;
	size_t len_B = 0;

	client->auth_data = srp_verifier_new(SRP_SHA256, SRP_NG_2048,
		client->getName().c_str(),
		(const unsigned char *) salt.c_str(), salt.size(),
		(const unsigned char *) verifier.c_str(), verifier.size(),
		(const unsigned char *) bytes_A.c_str(), bytes_A.size(),
		NULL, 0,
		(unsigned char **) &bytes_B, &len_B, NULL, NULL);

	if (!bytes_B) {
		actionstream << "Server: User " << client->getName()
			<< " tried to log in, SRP-6a safety check violated in _A handler."
			<< std::endl;
		if (wantSudo) {
			DenySudoAccess(pkt->getPeerId());
			return;
		} else {
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
			return;
		}
	}

	NetworkPacket resp_pkt(TOCLIENT_SRP_BYTES_S_B, 0, pkt->getPeerId());
	resp_pkt << salt << std::string(bytes_B, len_B);
	Send(&resp_pkt);
}

void Server::handleCommand_SrpBytesM(NetworkPacket* pkt)
{
	RemoteClient* client = getClient(pkt->getPeerId(), CS_Invalid);
	ClientState cstate = client->getState();

	bool wantSudo = (cstate == CS_Active);

	verbosestream << "Server: Recieved TOCLIENT_SRP_BYTES_M." << std::endl;

	if (!((cstate == CS_HelloSent) || (cstate == CS_Active))) {
		actionstream << "Server: got SRP _M packet in wrong state "
			<< cstate << " from "
			<< getPeerAddress(pkt->getPeerId()).serializeString()
			<< ". Ignoring." << std::endl;
		return;
	}

	if ((client->chosen_mech != AUTH_MECHANISM_SRP)
		&& (client->chosen_mech != AUTH_MECHANISM_LEGACY_PASSWORD)) {
		actionstream << "Server: got SRP _M packet, while auth"
			<< "is going on with mech " << client->chosen_mech
			<< " from " << getPeerAddress(pkt->getPeerId()).serializeString()
			<< " (wantSudo=" << wantSudo << "). Denying." << std::endl;
		if (wantSudo) {
			DenySudoAccess(pkt->getPeerId());
			return;
		} else {
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
			return;
		}
	}

	std::string bytes_M;
	*pkt >> bytes_M;

	if (srp_verifier_get_session_key_length((SRPVerifier *) client->auth_data)
			!= bytes_M.size()) {
		actionstream << "Server: User " << client->getName()
			<< " at " << getPeerAddress(pkt->getPeerId()).serializeString()
			<< " sent bytes_M with invalid length " << bytes_M.size() << std::endl;
		DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_UNEXPECTED_DATA);
		return;
	}

	unsigned char *bytes_HAMK = 0;

	srp_verifier_verify_session((SRPVerifier *) client->auth_data,
		(unsigned char *)bytes_M.c_str(), &bytes_HAMK);

	if (!bytes_HAMK) {
		if (wantSudo) {
			actionstream << "Server: User " << client->getName()
				<< " at " << getPeerAddress(pkt->getPeerId()).serializeString()
				<< " tried to change their password, but supplied wrong"
				<< " (SRP) password for authentication." << std::endl;
			DenySudoAccess(pkt->getPeerId());
			return;
		} else {
			actionstream << "Server: User " << client->getName()
				<< " at " << getPeerAddress(pkt->getPeerId()).serializeString()
				<< " supplied wrong password (auth mechanism: SRP)."
				<< std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_WRONG_PASSWORD);
			return;
		}
	}

	if (client->create_player_on_auth_success) {
		std::string playername = client->getName();
		m_script->createAuth(playername, client->enc_pwd);

		std::string checkpwd; // not used, but needed for passing something
		if (!m_script->getAuth(playername, &checkpwd, NULL)) {
			actionstream << "Server: " << playername << " cannot be authenticated"
				<< " (auth handler does not work?)" << std::endl;
			DenyAccess(pkt->getPeerId(), SERVER_ACCESSDENIED_SERVER_FAIL);
			return;
		}
		client->create_player_on_auth_success = false;
	}

	acceptAuth(pkt->getPeerId(), wantSudo);
}