HackRoom Guide e how-to protocols winmx in english by EaglE

When connecting to a channel the following things happen:
1. Server sends down "1" to the client indicating WinMX Compatibility
2. Client sends Encryption Key (Type 0x57 for Chat Client)
3. Server sends Encryption Key (Type 0x58 for Chat Server)
4. Client and server need to use the encryption key sent in step 3 to generate the send and receive pairs.
---- Communication from here on uses encryption based on the keys extracted in step 4 ----
5. Client sends 3.53 compatibility message (skipped for 3.31 clients)
6. Client sends join request
7. Server sends Join Reply (with luck)
8. Server sends 3.53 compatibility message (skipped for 3.31 servers)
9. Server sends Topic
10. Server sends MOTD
11. Server sends "some idiot joined" messages to everyone :-)

If you are making your own Server then its best to send any identifying signals between steps 8 and 9 (for example if you want to send down a type 0xFFFF so clients can know its your server). If clients wish to send off a certain data type to indicate the client then it should be done anywhere after the join request, but best to send after the join reply from the server.

Message Types:

Messages are in the form of:
[Type - 2 Bytes] [Length of data - 2 Bytes] [Data - Any Size]

Format shown is the "Data" part of the message, in the form [Data:Length] [Data:Length] (length is in bytes) {[Data:Length]} means optional field

Things to note:
Although the protocol uses 4 Bytes for File Count, WinMX only allows up to 65535, The reason for this is unknown.
Some Message Types have no requirements for data format (ie. you can send anything in the message content, it will ignore it and only nother with the message type), I have left the Data Format blank for these.
A Length of N means a Null Terminated String of any length.
The Primary IP and Port are the IP and UDP Port of your primary user, used for directing Browse/Whois/PM's etc.
There are 4 Protocol's listed, 3.31 indicates the WinMX 3.31 protocol,3.53 indicates the WinMX 3.53 protocol, RoboMX indicates Benders additions to the protocol, and Extended indicate KM's additions to the protocol.

Type	Sender	Name	Protocol	Description	Data Format
0x0064	Client	Join Request	Both	Request to join the room	[RoomName:N] [Connection:2] [PrimaryIP:4] [PrimaryPort:2] [Files:4] [UserName:N]
0x0065	Client	User rename	Both	Request to change username	[Connection:2] [PrimaryIP:4] [PrimaryPort:2] [Files:4] [UserName:N]
0x0066	Server	Join Reply	Both	You have joined the room
0x0068	Server	3.53 Support	3.53	Indicates the server supports the 3.53 Protocol
0x0069	Server	RoboMX Channel	RoboMX	Indicates the channel is hosted on RoboMX, Disconnect if you receive that! :-)
0x006E	Server	User Entered	3.31	A New User has Entered	[UserName:N] [PrimaryIP:4] [PrimaryPort:2] [Connection:2] [Files:4]
0x006F	Server	User Notification	3.31	For sending the initial user list to the user	[UserName:N] [PrimaryIP:4] [PrimaryPort:2] [Connection:2] [Files:4]
0x0070	Server	User Rename	3.31	User has changed Name	[OldName:N] [OldPrimaryIP:4] [OldPrimaryPort:2] [NewName:N] [NewPrimaryIP:4] [NewPrimaryPort:2] [Connection:2] [Files:4]
0x0071	Server	User Entered	3.53	New User Entered (no IP shown)	[UserName:N] [PrimaryIP:4] [PrimaryPort:2] [Connection:2] [Files:4] [Rank:1]
0x0072	Server	User Notification	3.53	For sending the initial user list to the user	[UserName:N] [PrimaryIP:4] [PrimaryPort:2] [Connection:2] [Files:4] [Rank:1]
0x0073	Server	User Exit	Both	User has left	[UserName:N] [PrimaryIP:4] [PrimaryPort:2]
0x0074	Server	User Rename	3.53	User has changed Name, Note: Renames are also used for changes in a users level	[OldName:N] [OldPrimaryIP:4] [OldPrimaryPort:2] [NewName:N] [NewPrimaryIP:4] [NewPrimaryPort:2] [Connection:2] [Files:4] [Rank:1]
0x0075	Server	User Entered	3.53	New User Entered (IP Shown)	[UserName:N] [PrimaryIP:4] [PrimaryPort:2] [Connection:2] [Files:4] [Rank:1] [IP:4]
0x0078	Server	MOTD	Both	Initial MOTD / MOTD Change	[MOTD:N]
0x00C9	Server	Normal Text	Both	For Normal text in the channel: <John> hello bob	[UserName:N] [Text:N]{[Rank:1]}
0x00C9	Client	Normal Text	3.31	Sends Normal Text	[Text:N]
0x00CA	Client	Action Text	3.31	Sends Action Text	[Text:N]
0x00CB	Server	Action Text	Both	For Action text in the channel: John waves to bob	[UserName:N] [Text:N]
0x00D2	Server	General Text	3.53	Normally used for Server responses (eg. "Unknown Command") Also used for OPMsg/Watchcmds and other such messages. Also used for Colour Text	[Text:N]
0x00D3	Server	Admin Command	3.53	Typed Command (echo's back the command you entered)	[Text:N]
0x012C	Server	Topic	Both	Initial Topic / Topic Change	[Topic:N]
0x012D	Server	Channel Renamed	3.53	The Channel name has changed (/setchannelname command)	[ChannelName:N]
0x0190	Server	Redirect	Both	Room Redirected	[ChannelName:N]
0x13ED	Client	3.53 Support	3.53	Sent by client before join request to indicate 3.53 support	[0x31:1]
0x13EE	Client	Redirected	3.53	Sent by 3.53 clients that have been redirected (for Redirect blocking)	[Channel Name:N]
0x1450	Client	Text	3.53	Sends Text to the room (Text should be sent exactly as typed)	[Text:N]
0x9900	Server	IP Send Support	Extended	When users are admined, Checks if they support IPSend
0x9901	Client	IP Send Support	Extended	Response to IPSend Support Test (indicates IPSend is Supported)
0x9902	Server	Users IP	Extended	Sending of the IP to the client Note: the IP can either be the IP Address "1.2.3.4" or the IP with Hostname in square brackets "1.2.3.4 [some.hostname.com]"	[UserName:N] [PrimaryIP:4] [PrimaryPort:2] [Files:4] [Connection:2] [Rank:1] [IP:N]
0x9903	Server	IPSend Complete	Extended	Indicates Completion of IPSend
0x9904	Server	Colour Code	Extended	Used by Colour Servers to inform Clients of the channels Colour Codes (for Compatible Bots to detect UserNames properly)	[ColourCodeString:N]
0x9905	Both	Identify	Extended	So compatible Clients and Servers can detect each others version number	[Name:N] [Version:N]
0x9906	Server	Text Flood	Extended	Indicates either about to send a large amount of text, or finished sending Parameter is 1 for start, 0 for end	[StartOrEnd:1]
0x9907	Server	User Menus	Extended	Allows the Server to transmit Right click menu's to clients Type: 0=Supported, 1=UserMenu, 2=ChannelMenu, 3=Scroll Wheel	[Type:1] [Title:N] [MenuType:2] [Command:N]
0x9907	Client	User Menus	Extended	Indicates Support for User Menu Send (response to 0x9907 type 0)
0xFDE8	Both	Ping	Both	Pings should be sent every 45-60 seconds to keep the connection alive Note: Official WinMX 3.53 Sends every 300 seconds but this causes problems with some firewalls so lower values are recommended.