Ed2k protocol - Revision history

Abeco at 13:19, 9 June 2008

2008-06-09T13:19:28Z

76.68.241.227: /* ed2k protocol */

2008-03-29T06:34:39Z

‎ed2k protocol

Abeco: =Login message=

2007-02-24T13:25:23Z

=Login message=

Abeco: =Login message=

2007-02-24T13:23:57Z

=Login message=

Abeco: =Login message= Correct colours

2007-02-22T20:56:27Z

=Login message= Correct colours

Abeco: =Login message=

2007-02-22T20:55:00Z

=Login message=

Abeco: corrections: message and message tag

2007-02-22T20:51:25Z

corrections: message and message tag

Abeco at 16:07, 22 February 2007

2007-02-22T16:07:26Z

New page

=ed2k protocol=

The amule client uses the ed2k protocol to connect to the server. This page is based on the document of emule-project.net called: "The eMule/eDonkey protocol specification" by Yoram Kulbak and Danny Bickson and intents to update all messages that have changed in order that anyone can understand ed2k protocol, be able to implement it and to understand actual source codes like amule.

This page pretends to be an explanation on how to connect to the ed2k servers, perform searchs, file sharing, etc. Note: It is created by a newbie and WILL have errors, so I hope that people can help me to complete this article.

First of all. ALL MESSAGES ARE ENCODED IN [http://en.wikipedia.org/wiki/Little_endian LITTLE ENDIAN] (the opposite of natural order).

==Messages==

==Tag messages==

==Login message==

In order to connect to the network, you must have an IP address and port of an emule server. For example, if you have a emule server runing at localhost, the host will be: localhost and the port that you have configured.

After connecting, you must sent the first message to the server, this message is composed by (as the howto says):

HEADER
protocol 1 byte (default value for EMULE: 0xE3)
size 4 bytes (the size of the message not including this header)
type 1 byte (OP_LOGINREQUEST: 0x01)

userhash 16 bytes generated randomly (it is said that positions 6th and 15th are not randomly generated, and their values are 14 and 111 respectively).
clientID 4 bytes (the fist time are 0x00 because the clientID is assigned by server).
TCPport 2 bytes (default: 4662: 0x36 0x12)
TagCount 4 bytes (default: 4: 0x04 0x00 0x00 0x00). CAUTION: In spite of having the name TAG is NOT a tag message.
THE TAGS (Problem: I still don't understand very well how amule creates and sends):
nametag Is a String tag (not fixed length)
versiontag 8 bytes
porttag 8 bytes
flagstag 8 bytes

==How to do test==

If you are runing linux and your own donkey server
tcpdump -i lo -X

can be really usefull (lo is the loopback interface). If you want to perform translations from binary to hexadecimal
hexdump -C
is usefull too.

For example, I use netcat with hexdump to "emulate" a server:
nc -l -p PORT|hexdump -C

This allows me to see byte per byte all the login message (for example).

If you want to run your own edonkey server to perform some test and not to be banned from some official servers you can download it from:

@@ Line 44: / Line 44: @@
   TCPport   2 bytes (default: 4662: 0x36 0x12) [yellow]
   TagCount  4 bytes (default: 4: 0x04 0x00 0x00 0x00). CAUTION: In spite of having the name TAG is NOT a tag message. [White]
 This is a screenshot which uses netcat on the port 46621 and hexdump to examine the login message. All fields underlined on different colors are identified, the rest are messages tags that are explained below.
-[[Amule_Hexdump|http://img86.imageshack.us/img86/7065/datoshe0.png]]
+[[Image:datos0.png]]
 '''Tag explanation according to the image (thanks skolnick):'''
   Type of tag     (1 byte)        0x02 = String

@@ Line 57: / Line 57: @@
 '''Tag explanation according to the image (thanks skolnick):'''
-Type of tag     (1 byte)        0x02 = String
+ Type of tag     (1 byte)        0x02 = String
-tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
+ tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
-tag name        (1 byte)        0x01 = tag name is client nickname
+ tag name        (1 byte)        0x01 = tag name is client nickname
-tag's size      (2 bytes)       0x14 0x00 = size is 20 bytes
+ tag's size      (2 bytes)       0x14 0x00 = size is 20 bytes
-tag contents    (20 bytes)      http://www.amule.org
+ tag contents    (20 bytes)      http://www.amule.org
-−
-Type of tag     (1 byte)        0x03 = DWORD
+ Type of tag     (1 byte)        0x03 = DWORD
-tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
+ tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
-tag name        (1 byte)        0x11 = tag name is protocol version
+ tag name        (1 byte)        0x11 = tag name is protocol version
-tag contents    (4 bytes)       0x3c 0x00 0x00 0x00 = prot. version 60
+ tag contents    (4 bytes)       0x3c 0x00 0x00 0x00 = prot. version 60
-−
-Type of tag     (1 byte)        0x03 = DWORD
+ Type of tag     (1 byte)        0x03 = DWORD
-tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
+ tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
-tag name        (1 byte)        0x20 = tag name is compresion
+ tag name        (1 byte)        0x20 = tag name is compresion
-tag contents    (4 bytes)       0x1d 0x00 0x00 0x00 = compression status
+ tag contents    (4 bytes)       0x1d 0x00 0x00 0x00 = compression status
-−
-Type of tag     (1 byte)        0x03 = DWORD
+ Type of tag     (1 byte)        0x03 = DWORD
-tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
+ tag name's size (2 bytes)       0x01 0x00 = tag name's size is 1 byte
-tag name        (1 byte)        0xfb = tag name is ???
+ tag name        (1 byte)        0xfb = tag name is ???
-tag contents    (4 bytes)       0x80 0x05 0x04 0x03 = tag data
+ tag contents    (4 bytes)       0x80 0x05 0x04 0x03 = tag data
 ==How to do tests==

@@ Line 44: / Line 44: @@
   TCPport   2 bytes (default: 4662: 0x36 0x12) [yellow]
   TagCount  4 bytes (default: 4: 0x04 0x00 0x00 0x00). CAUTION: In spite of having the name TAG is NOT a tag message. [White]
-THE TAGS (Problem: I still don't understand very well how amule creates and sends):
+THE TAGS:
   nametag   Is a String tag (not fixed length)
   versiontag 8 bytes
   porttag    8 bytes
   flagstag   8 bytes
-−
-This is a screenshot which uses netcat on the port 46621 and hexdump to examine the login message. All fields underlined on different colors are identified, the rest are messages tags that I am not able to recognice.
 [[Amule_Hexdump|http://img86.imageshack.us/img86/7065/datoshe0.png]]
 ==How to do tests==

@@ Line 40: / Line 40: @@
   type      1 byte (OP_LOGINREQUEST: 0x01) [Blue]
-  userhash  16 bytes generated randomly (it is said that positions 6th and 15th are not randomly generated, and their values are 14 and 111 respectively).
+  userhash  16 bytes generated randomly (it is said that positions 6th and 15th are not randomly generated, and their values are 14 and 111 respectively). [purple]
-  clientID  4 bytes (the fist time are 0x00 because the clientID is assigned by server). [purple]
+  clientID  4 bytes (the fist time are 0x00 because the clientID is assigned by server). [white]
   TCPport   2 bytes (default: 4662: 0x36 0x12) [yellow]
   TagCount  4 bytes (default: 4: 0x04 0x00 0x00 0x00). CAUTION: In spite of having the name TAG is NOT a tag message. [White]

@@ Line 52: / Line 52: @@
 This is a screenshot which uses netcat on the port 46621 and hexdump to examine the login message. All fields underlined on different colors are identified, the rest are messages tags that I am not able to recognice.
-img-screenshot-datos.png
+[[Amule_Hexdump|http://img86.imageshack.us/img86/7065/datoshe0.png]]
 ==How to do tests==

← Older revision	Revision as of 06:34, 29 March 2008
(No difference)

@@ Line 8: / Line 8: @@
 ==Messages==
 ==Tag messages==
 ==Login message==
@@ Line 18: / Line 36: @@
 HEADER
-  protocol  1 byte (default value for EMULE: 0xE3)
+  protocol  1 byte (default value for EMULE: 0xE3). [Red]
-  size      4 bytes (the size of the message not including this header)
+  size      4 bytes (the size of the message not including this header) [Green]
-  type      1 byte (OP_LOGINREQUEST: 0x01)
+  type      1 byte (OP_LOGINREQUEST: 0x01) [Blue]
   userhash  16 bytes generated randomly (it is said that positions 6th and 15th are not randomly generated, and their values are 14 and 111 respectively).
-  clientID  4 bytes (the fist time are 0x00 because the clientID is assigned by server).
+  clientID  4 bytes (the fist time are 0x00 because the clientID is assigned by server). [purple]
-  TCPport   2 bytes (default: 4662: 0x36 0x12)
+  TCPport   2 bytes (default: 4662: 0x36 0x12) [yellow]
-  TagCount  4 bytes (default: 4: 0x04 0x00 0x00 0x00). CAUTION: In spite of having the name TAG is NOT a tag message.
+  TagCount  4 bytes (default: 4: 0x04 0x00 0x00 0x00). CAUTION: In spite of having the name TAG is NOT a tag message. [White]
 THE TAGS (Problem: I still don't understand very well how amule creates and sends):
   nametag   Is a String tag (not fixed length)
@@ Line 32: / Line 50: @@
   flagstag   8 bytes
-==How to do test==
+img-screenshot-datos.png
 If you are runing linux and your own donkey server
@@ Line 48: / Line 69: @@
 If you want to run your own edonkey server to perform some test and not to be banned from some official servers you can download it from: