Network protocol (Worms 2)

(Up to Game logic)

The Worms 2 servers host rooms in which users can meet to then connect to each other's PCs for playing games.

Official servers

The following servers are hosted by Team17:

Name	IP address	Port	Notes
Worms2 Server (UK)	uk1.servers.worms2.com	17000	"The Team17 Server". Started to reject new connections in July 2020, shortly after some Worms enthusiasts played on it. Unclear whether the sudden activity downed it, it did not immediately break. The client will display "Unable to create new player..." when attempting to connect to it.
Worms2 Demo Server (UK)	uk1.servers.worms2.com	17171	Server for Worms 2 demo. Allows full versions to connect aswell. Did not go down in July 2020.

Server communication

The server hosting the user, room, and game lists communicates with packets in the following format:

Packet format

Offset	Type	Size	Name	Description
0	uint32	4	Code	Determines the type of packet. Known packets are listed below.
4	uint32	4	Flags	A bitset determining which of the following fields will be available.
?	uint32	4	Value 0	If bit 0 is set in Flags.
?	uint32	4	Value 1	If bit 1 is set in Flags.
?	uint32	4	Value 2	If bit 2 is set in Flags.
?	uint32	4	Value 3	If bit 3 is set in Flags.
?	uint32	4	Value 4	If bit 4 is set in Flags. Never used other than client-side?
?	uint32	4	Value 10	If bit 10 is set in Flags.
?	uint32	4	Data Length	If bit 5 is set in Flags.
?	char[DataLength]	Data Length	Data	If bit 5 is set in Flags, stores Windows-1251 encoded text like an IP string or full chat message.
?	uint32	4	Error	If bit 7 is set in Flags. Returns a Windows error code from the server, like E_FAIL for when the name of a room to create contains a bad word.
?	char[20]	20	Name	If bit 8 is set in Flags, stores a Windows-1251 encoded session name. Unused bytes are 0.
?	Session info	50	Session	If bit 9 is set in Flags. Unused bytes are 0.

Session info

Several packets identify a user, room, or game with the Name and Session fields. The latter provides the following information:

Offset	Type	Size	Value
0	uint32	4	Always 0x17171717
4	uint32	4	Always 0x02010101
8	uint8	1	Nation / Flag
9	uint8	1	Game version, always 49
10	uint8	1	Game release (same as Game version, 50 if CD check failed)
11	uint8	1	Type (1=room, 4=game, 5=user)
12	uint8	1	Access (1=public, 2=protected)
13	uint8	1	Always 1
14	uint8	1	Always 0
15	gap	35	Unused, all 0.

Passing other or invalid combinations (protected users and rooms do not exist, only passworded games) will display a French flag with the default state or a question mark in the UI.

The Worms 2 1.0.1.1 Demo uses significantly different values compared to the full version 1.0.1.5 patch, causing said question marks to appear. However, interactions with full version users still work.

Nation / Flag

Determines which flag is displayed with the user, room, or game. Two flags are custom (Skull and Team17) and are not normally selectable. Des patch can unlock the selection of them, and adds another entry for an "invalid" country code, creating an empty flag.

Value	Flag
1	United Kingdom
2	Argentinia
3	Australia
4	Austria
5	Beglium
6	Brazil
7	Canada
8	Croatia
9	Bosnia and Herzegovina (old flag)
10	Cyprus
11	Czech Republic
12	Denmark
13	Finland
14	France
15	Georgia
16	Germany
17	Greece
18	Hong Kong SAR
19	Hungary
20	Iceland
21	India
22	Indonesia
23	Iran
24	Iraq
25	Ireland
26	Israel
27	Italy
28	Japan
29	Liechtenstein
30	Luxembourg
31	Malaysia
32	Malta
33	Mexico
34	Morocco
35	Netherlands
36	New Zealand
37	Norway
38	Poland
39	Portugal
40	Puerto Rico
41	Romania
42	Russian Federation
43	Singapore
44	South Africa
45	Spain
46	Sweden
47	Switzerland
48	Turkey
49	United States
50	Skull image
51	Team17 logo

Game release

Becomes 50 if CD detection failed. The CD detection consists of the following tests:

• Find CD drive, where drives A: and B: are ignored - a found drive letter is stored in the registry under HKCU\SOFTWARE\Team17SoftwareLTD\Worms2\CD. (error 2 otherwise)
• Check the CD being "Worms 2" or "WORMS2". (error 1 otherwise)
• Check if the CD has no free space to ensure it being a CD-ROM. (error 3 otherwise)
• Check if the CD stores an "autorun.inf" file. (error 4 otherwise)

Packet contents

As specified above, the Code of a packet determines the Action to take on either the server or client side and in effect which fields are used. Some codes are reused for multiple occassions, and some are unused in the 1.0.1.5 patch.

Client query packets are also used for server notices, represented by the Type column in the following table:

• Query: A client query to execute an action on the server, always getting a reply (even codes only).
• Reply: A server reply to a client query, always reporting back an Error code, 0 for success (odd codes only).
• Notice: Same as query, but coming as an out-of-bound server packet to update the state on the client, like when another user joins or creates a game.

Note that the same ID counter is incremented for users (UID), rooms (RID), and games (GID). If a user logs in with UID 3 and immediately creates a room, the RID will be 4.

Code	Action	Type	Value 0	Value 1	Value 2	Value 3	Value 4	Value 10	Data	Name / Session
50	not used	Query					?
51	not used	Reply					?
200	List Rooms	Query					0
300	not used	Query					0
350	List Item	Reply		UID / RID / GID					user / creator / host IP	user / room / game
351	List End	Reply
400	List Users	Query			UID		0
500	List Games	Query			UID		0
600	Login	Query		0			0			local user
600	Login	Notice		remote UID			0			remote user
601	Login	Reply		local UID
700	Create Room	Query		0			0		creator IP	room
700	Create Room	Notice		new RID			0		creator IP	room
701	Create Room	Reply		new RID
800	Join Room / Game	Query			joined RID / GID			local UID
800	Join Room / Game	Notice			joined RID / GID			remote UID
801	Join Room / Game	Reply
900	Leave Room	Query			left RID			local UID
900	Leave Room	Notice			left RID			remote UID
901	Leave Room	Reply
1000	Disconnect User	Query						local UID
1000	Disconnect User	Notice						remote UID
1001	Disconnect User	Reply
1100	Close Room	Query						RID
1100	Close Room	Notice						RID
1101	Close Room	Reply
1200	Create Game	Query			RID		GID?		host IP	host
1200	Create Game	Notice			RID		GID?		host IP	host
1201	Create Game	Reply		GID
1300	Room Chat	Query	local UID			receiver RID / UID			"GRP:[ UserName ]  Message" / "PRV:[ UserName ]  Message"
1300	Room Chat	Notice	remote UID			receiver RID / UID			"GRP:[ UserName ]  Message" / "PRV:[ UserName ]  Message"
1301	Room Chat	Reply
1320	not used	Query	?						?
1321	not used	Reply
1322	not used	Query	?						?
1323	not used	Reply
1324	not used	Query	?
1325	not used	Reply							?
1326	Connect Game	Query	GID
1327	Connect Game	Reply							host IP

Game room communication

The players are connected via P2P using DirectPlay. This means the ports 47624 (for the lobby connection itself) and 2300 to 2400 (for each player connection) should be forwarded in any router. The fact that each player is connected to another means that the host can leave the game at any time, the remaining players can continue playing without dropping, unlike in Worms Armageddon or Worms World Party.

See also

• Selected sample logs