Classic伺服器協議

這是有關Minecraft Classic創造伺服器使用的伺服器協議的文檔

Minecraft.net交流

心跳

為了能從伺服器列表連接到Minecraft Classic中的伺服器，伺服器必須每隔幾分鐘向minecraft.net廣播一個所謂的「心跳」。

庫存伺服器會每隔45秒廣播一次心跳。

「心跳」使用了對https://minecraft.net/heartbeat.jsp發送HTTP請求的形式。發送心跳後，將返回伺服器的URL。

成功心跳的關鍵是你應該在HTTP請求中省略「www」，因為你要將它定位為URI，而不是URL。

它可以是GET或POST請求。下面表格是所需要的參數：

Name	Details
port	伺服器的端口號，通常為25565
max	伺服器上的最大玩家數量
name	伺服器的名稱
public	Whether the server is public (i.e. appears in the lobby) or not. Can be True or False, in that capitalization.
version	Minecraft version, this should be 7
salt	A random, 16-character base-62 salt
users	Number of users connected to the server

The simplest way to send a heartbeat is to open a TCP socket to port 80 on minecraft.net, and send the following (with the values changed, obviously):

GET /heartbeat.jsp?port=25565&max=32&name=My%20Server&public=True&version=7&salt=wo6kVAHjxoJcInKx&users=0, plus a CRLF(Carriage-return and Line feed).

Make sure any strings, like name, are escaped.

If everything goes well, in the response body you'll receive a URL to the server. Otherwise you'll get a nice HTML error message. There aren't any HTML headers to parse, as the HTTP version is not specified so HTTP/0.9 is used, which does not have headers.

用戶認證

The "key" provided when a user joins the server can be compared to the MD5 checksum of the server's "salt" plus the username to verify that the user is logged in to minecraft.net with that username. This is useful for establishing enough trust of the name provided to ban or op the player by name.

if( player.key == md5( server.salt + player.name ) ) {
 // player is logged in via minecraft.net
} else {
 // player is forging the username
}

This is also the way that Notch prevents "cracked," or pirated, clients from accessing online servers. When a cracked client tries to connect to an online server, an error will come up at the connection screen saying, "Failed to Connect: User Not Premium"

Note: This means that you should make sure your "salt" is kept a secret and shared only with heartbeat.jsp. If your server's "salt" is visible anywhere to users, it is trivial for users to produce valid-looking "key"s without being logged in to minecraft.net.

資料包協議

Every packet starts with a byte representing the Packet ID.

協議數據類型

Type	Size [bytes]	Description
Byte	1	Single byte integer (0 to 255)
SByte	1	Single byte signed integer (-128 to 127)
Short	2	Signed integer, network order (-32768 to 32767)
String	64	US-ASCII/ISO646-US encoded string padded with spaces (0x20)
Byte array	1024	Binary data padded with null bytes (0x00)

客戶端→服務端資料包

Packet ID	Purpose	Field Description	Field Type	Notes
0x00	Player Identification	Packet ID	Byte	Sent by a player joining a server with relevant information. Current protocol version is 0x07.
		Protocol version	Byte
		Username	String
		Verification key	String
		Unused	Byte
0x05	Set Block	Packet ID	Byte	Sent when a user changes a block. The mode field indicates whether a block was created (0x01) or destroyed (0x00). Block type is always the type player is holding, (even when deleting). Client assumes that this command packet always succeeds, and so draws the new block immediately. To disallow block creation, server must send back Set Block packet with the old block type. The XYZ coordinates of the block are just integers representing the coordinate of the block. (As opposed to player coordinates where the lower 5 bits are fractional coordinates)
		X	Short
		Y	Short
		Z	Short
		Mode	Byte
		Block type	Byte
0x08	Position and Orientation	Packet ID	Byte	Sent frequently (even while not moving) by the player with the player's current location and orientation. Player ID is always 255, referring to itself. Player coordinates are fixed-point values with the lowest 5 bits representing the fractional position (i.e. divide by 32 to get actual position in terms of block coordinates). The angle parameters are scaled such that a value of 256 would correspond to 360 degrees.
		Player ID	Byte
		X	Short
		Y	Short
		Z	Short
		Yaw (Heading)	Byte
		Pitch	Byte
0x0d	Message	Packet ID	Byte	Contain chat messages sent by player.
		Unused, maybe message color	Byte (0xFF)
		Message	String

服務端→客戶端資料包

Packet ID	Purpose	Field Description	Field Type	Notes
0x00	Server Identification	Packet ID	Byte	Response to a joining player. The user type indicates whether a player is an op (0x64) or not (0x00) Current protocol version is 0x07.
		Protocol version	Byte
		Server name	String
		Server MOTD	String
		User type	Byte
0x01	Ping	Packet ID	Byte	Sent to clients periodically. The only way a client can disconnect at the moment is to force it closed, which does not let the server know. The ping packet is used to determine if the connection is still open.
0x02	Level Initialize	Packet ID	Byte	Notifies player of incoming level data.
0x03	Level Data Chunk	Packet ID	Byte	Contains a chunk of gzipped map (not level.dat file). After decompression the map consists of an int(4 bytes) containing number of blocks + raw map array. (chunk is up to 1024 bytes, padded with 0x00s if less).
		Chunk Length	Short
		Chunk Data	Byte Array
		Percent Complete	Byte
0x04	Level Finalize	Packet ID	Byte	Sent after level data is complete and gives map dimensions. The y coordinate is how tall the map is.
		X Size	Short
		Y Size	Short
		Z Size	Short
0x06	Set Block	Packet ID	Byte	Sent to indicate a block change by physics or by players. In the case of a player change, the server will also echo the block change back to the player who initiated it.
		X	Short
		Y	Short
		Z	Short
		Block Type	Byte
0x07	Spawn Player	Packet ID	Byte	Sent to indicate where a new player is spawning in the world. Position and orientation are encoded the same as for packet 0x08 below.
		Player ID	SByte
		Player Name	String
		X	Short
		Y	Short
		Z	Short
		Yaw (Heading)	Byte
		Pitch	Byte
0x08	Position and Orientation (Player Teleport)	Packet ID	Byte	Sent with changes in player position and rotation. Teleports player it's sent to if player ID < 0 (For sending initial position in map, and /tp)
		Player ID	SByte
		X	Short
		Y	Short
		Z	Short
		Yaw (Heading)	Byte
		Pitch	Byte
0x09	Position and Orientation Update	Packet ID	Byte	Sent with changes in player position and rotation. Sent when both position and orientation is changed at the same time. Not required for server operation.
		Player ID	SByte
		Change in X	SByte
		Change in Y	SByte
		Change in Z	SByte
		Yaw (Heading)	Byte
		Pitch	Byte
0x0a	Position Update	Packet ID	Byte	Sent with changes in player position. Not required for server operation.
		Player ID	SByte
		Change in X	SByte
		Change in Y	SByte
		Change in Z	SByte
0x0b	Orientation Update	Packet ID	Byte	Sent with changes in player rotation. Not required for server operation.
		Player ID	SByte
		Yaw (Heading)	Byte
		Pitch	Byte
0x0c	Despawn Player	Packet ID	Byte	Sent when player disconnects.
		Player ID	SByte
0x0d	Message	Packet ID	Byte	Messages sent by chat or from the console.
		Player ID	SByte
		Message	String
0x0e	Disconnect player	Packet ID	Byte	Sent to a player when they're disconnected from the server. "Cheat detected: Distance" - happens not only when setting tile too far away from the player (how far is maximum distance and how it is measured?), but also when player moves and then immediately builds. "Cheat detected: Tile type"
		Disconnect reason	String
0x0f	Update user type	Packet ID	Byte	Sent when a player is opped/deopped Will give or remove the client's ability of breaking Bedrock blocks User type can be either 100, which will allow the player, or 0, which will disallow the player to break Bedrock blocks
		User type	Byte

玩家位置

固定點

Player position is represented via X, Y, and Z fixed-point coordinates. The fractional portion is 5 bits, so dividing the short integers received in position update packets by 32, you will have floating point coordinates for the player. This position corresponds to the center of the client viewport.

站在東西上

The bottom of the player's feet is located 1.59375 (fixed-point: 51) units below the center of the viewport, so to position the player on top of a particular block you could send a teleport (0x08) packet specifying a Y value based on the block position as: (Y x 32 + 51)

朝向

A yaw value of 0 means the player is facing in the Z- (negative Z) direction. This value increases in a clockwise direction as seen from above. If we call the negative Z direction "North", then a yaw of 64 means "East", 128 means "South", and 192 means "West".

A pitch value of 0 means level and this value increases in a downward direction. 64 is down, and 192 is up. Values of 65 to 191 should never occur because the player cannot look further up or down than the 64 → 0, 255 → 192 range. However, the Minecraft Classic client does not ignore invalid values, so it is possible to make players' heads "upside-down".

顏色代碼

  本文章介紹的是classic server protocol。關於the updated color codes used in the current version of Minecraft，請見「Formatting codes」。

Messages sent from the server to the client can contain color codes, which allow coloring of text for various purposes.

An ampersand symbol (&) followed by a hex digit in the message tells the client to switch colors while displaying text. The current version of the game uses a section (§) symbol, but the 0.30 version uses ampersands. For the formatting codes for the current version of the game, see Formatting codes.

Color coding at the start of the message will only work if the player ID byte is less than 127. If it's 127 or higher, the game automatically adds &e before the message, making it yellow. However, color codes after the first character still work. If you use an ID below 127, it doesn't add a color code, so the ones you use will work.

Hex digit to color mapping.

Sample	Code	Common Name	Alternate Name	Foreground Color				Background Color
				R	G	B	HEX	R	G	B	HEX
	&0	Black	Black	0	0	0	#000	0	0	0	#000000
	&1	Dark Blue	Navy	0	0	170	#00A	0	0	42	#00002A
	&2	Dark Green	Green	0	170	0	#0A0	0	42	0	#002A00
	&3	Teal	Teal	0	170	170	#0AA	0	42	42	#002A2A
	&4	Dark Red	Maroon	170	0	0	#A00	42	0	0	#2A0000
	&5	Purple	Purple	170	0	170	#A0A	42	0	42	#2A002A
	&6	Dark Yellow	Gold	170	170	0	#AA0	42	42	0	#2A2A00
	&7	Gray	Silver	170	170	170	#AAA	42	42	42	#2A2A2A
	&8	Dark Gray	Gray	85	85	85	#555	21	21	21	#151515
	&9	Indigo	Blue	85	85	255	#55F	21	21	63	#15153F
	&a	Bright Green	Lime	85	255	85	#5F5	21	63	21	#153F15
	&b	Cyan	Aqua	85	255	255	#5FF	21	63	63	#153F3F
	&c	Red	Red	255	85	85	#F55	63	21	21	#3F1515
	&d	Pink	Pink	255	85	255	#F5F	63	21	63	#3F153F
	&e	Yellow	Yellow	255	255	85	#FF5	63	63	21	#3F3F15
	&f	White	White	255	255	255	#FFF	63	63	63	#3F3F3F