[Solved]D2 Game Server Packets

[Tazo]

do a google search for free c++ compiler

[OnlyMeat]

do a google search for free c++ compiler

Actually there is nothing in that code that is c++. You could compile it in pure c.

[shout]

I wonder what

Code Select Expand


assert(0)

did. The tool tip is as follows:

Code Select Expand


#define assert((void)0)


[Ringo]

Just use D2Client.dll

I looked everywhere for it and all i could find was  this: http://forum.valhallalegends.com/phpbbs/index.php?topic=3357.0

Also thanks Shout / laurion for helping!

[Tazo]

yea that was a bad .dll so i fixed it, here
d2.zip
should work fine now.

source:
d2source.zip
source is C; was made using Dev-C++

[Ringo]

yea that was a bad .dll so i fixed it, here
d2.zip
should work fine now.

source:
d2source.zip
source is C; was made using Dev-C++

Thanks!
Im still getting the same problem, Entry point in the dll not found.
I found dev c++ on the web and downloaded it but have no clue how to use it.
Also im not sure how to open the source files correctly. (cant get it to compile)
I was wundering if it was how i was trying to call the functions or if it was the functions not letting me call them.
How would i open the 2 files together and change the functions from:

Code Select Expand


unsigned char*GamePacketSize(unsigned char *data, unsigned int *size,
                             unsigned int *offset)

int GamePacketDecode(unsigned char *indata, unsigned int insize,
                    unsigned char *outdata, unsigned int outmax,
                    unsigned int *outsize)


to:

Code Select Expand


unsigned char __stdcall *GamePacketSize(unsigned char *data, unsigned int *size,
                             unsigned int *offset)

int __stdcall  GamePacketDecode(unsigned char *indata, unsigned int insize,
                    unsigned char *outdata, unsigned int outmax,
                    unsigned int *outsize)


And would there be anything else that would need to be changed to call the functions like this?

Again thank you very much for helping!

[Blaze]

Wait a minute... http://www.clanvl.net/ ?

[QwertyMonster]

Wait a minute... http://www.clanvl.net/ ?

How does that help, or even on topic?..

[Warrior]

Are you exporting the functions (using a .def file) correctly?

[Ringo]

Hmm iv tryed following tha tutorial as a referance, but it seems somwhat differnt to how it shows to do it, aslo i had the source  laurion posted as a dev referance, thanks!

Iv created new project in dev c++ with a c and a h file, iv got this atm (it does return some strange shit)

the c file:

Code Select Expand


/* Replace "dll.h" with the name of your header */
#include "dll.h"
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>

unsigned int CharIndex[] = {
   0x0247, 0x0236, 0x0225, 0x0214, 0x0203, 0x01F2, 0x01E1, 0x01D0,
   0x01BF, 0x01AE, 0x019D, 0x018C, 0x017B, 0x016A, 0x0161, 0x0158,
   0x014F, 0x0146, 0x013D, 0x0134, 0x012B, 0x0122, 0x0119, 0x0110,
   0x0107, 0x00FE, 0x00F5, 0x00EC, 0x00E3, 0x00DA, 0x00D1, 0x00C8,
   0x00BF, 0x00B6, 0x00AD, 0x00A8, 0x00A3, 0x009E, 0x0099, 0x0094,
   0x008F, 0x008A, 0x0085, 0x0080, 0x007B, 0x0076, 0x0071, 0x006C,
   0x0069, 0x0066, 0x0063, 0x0060, 0x005D, 0x005A, 0x0057, 0x0054,
   0x0051, 0x004E, 0x004B, 0x0048, 0x0045, 0x0042, 0x003F, 0x003F,
   0x003C, 0x003C, 0x0039, 0x0039, 0x0036, 0x0036, 0x0033, 0x0033,
   0x0030, 0x0030, 0x002D, 0x002D, 0x002A, 0x002A, 0x0027, 0x0027,
   0x0024, 0x0024, 0x0021, 0x0021, 0x001E, 0x001E, 0x001B, 0x001B,
   0x0018, 0x0018, 0x0015, 0x0015, 0x0012, 0x0012, 0x0012, 0x0012,
   0x000F, 0x000F, 0x000F, 0x000F, 0x000C, 0x000C, 0x000C, 0x000C,
   0x0009, 0x0009, 0x0009, 0x0009, 0x0006, 0x0006, 0x0006, 0x0006,
   0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003,
   0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003, 0x0003,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000
};
unsigned char CharTable[] = {
   0x00,0x00,0x01,0x00,0x01,0x04,0x00,0xFF,0x06,0x00,0x14,0x06,
   0x00,0x13,0x06,0x00,0x05,0x06,0x00,0x02,0x06,0x00,0x80,0x07,
   0x00,0x6D,0x07,0x00,0x69,0x07,0x00,0x68,0x07,0x00,0x67,0x07,
   0x00,0x1E,0x07,0x00,0x15,0x07,0x00,0x12,0x07,0x00,0x0D,0x07,
   0x00,0x0A,0x07,0x00,0x08,0x07,0x00,0x07,0x07,0x00,0x06,0x07,
   0x00,0x04,0x07,0x00,0x03,0x07,0x00,0x6C,0x08,0x00,0x51,0x08,
   0x00,0x20,0x08,0x00,0x1F,0x08,0x00,0x1D,0x08,0x00,0x18,0x08,
   0x00,0x17,0x08,0x00,0x16,0x08,0x00,0x11,0x08,0x00,0x10,0x08,
   0x00,0x0F,0x08,0x00,0x0C,0x08,0x00,0x0B,0x08,0x00,0x09,0x08,
   0x01,0x96,0x09,0x97,0x09,0x01,0x90,0x09,0x95,0x09,0x01,0x64,
   0x09,0x6B,0x09,0x01,0x62,0x09,0x63,0x09,0x01,0x56,0x09,0x58,
   0x09,0x01,0x52,0x09,0x55,0x09,0x01,0x4D,0x09,0x50,0x09,0x01,
   0x45,0x09,0x4C,0x09,0x01,0x40,0x09,0x43,0x09,0x01,0x31,0x09,
   0x3B,0x09,0x01,0x28,0x09,0x30,0x09,0x01,0x1A,0x09,0x25,0x09,
   0x01,0x0E,0x09,0x19,0x09,0x02,0xE2,0x0A,0xE8,0x0A,0xF0,0x0A,
   0xF8,0x0A,0x02,0xC0,0x0A,0xC2,0x0A,0xCE,0x0A,0xE0,0x0A,0x02,
   0xA0,0x0A,0xA2,0x0A,0xB0,0x0A,0xB8,0x0A,0x02,0x8A,0x0A,0x8F,
   0x0A,0x93,0x0A,0x98,0x0A,0x02,0x81,0x0A,0x82,0x0A,0x83,0x0A,
   0x89,0x0A,0x02,0x7C,0x0A,0x7D,0x0A,0x7E,0x0A,0x7F,0x0A,0x02,
   0x77,0x0A,0x78,0x0A,0x79,0x0A,0x7A,0x0A,0x02,0x73,0x0A,0x74,
   0x0A,0x75,0x0A,0x76,0x0A,0x02,0x6E,0x0A,0x6F,0x0A,0x70,0x0A,
   0x72,0x0A,0x02,0x61,0x0A,0x65,0x0A,0x66,0x0A,0x6A,0x0A,0x02,
   0x5D,0x0A,0x5E,0x0A,0x5F,0x0A,0x60,0x0A,0x02,0x57,0x0A,0x59,
   0x0A,0x5A,0x0A,0x5B,0x0A,0x02,0x4A,0x0A,0x4B,0x0A,0x4E,0x0A,
   0x53,0x0A,0x02,0x46,0x0A,0x47,0x0A,0x48,0x0A,0x49,0x0A,0x02,
   0x3F,0x0A,0x41,0x0A,0x42,0x0A,0x44,0x0A,0x02,0x3A,0x0A,0x3C,
   0x0A,0x3D,0x0A,0x3E,0x0A,0x02,0x36,0x0A,0x37,0x0A,0x38,0x0A,
   0x39,0x0A,0x02,0x32,0x0A,0x33,0x0A,0x34,0x0A,0x35,0x0A,0x02,
   0x2B,0x0A,0x2C,0x0A,0x2D,0x0A,0x2E,0x0A,0x02,0x26,0x0A,0x27,
   0x0A,0x29,0x0A,0x2A,0x0A,0x02,0x21,0x0A,0x22,0x0A,0x23,0x0A,
   0x24,0x0A,0x03,0xFB,0x0B,0xFC,0x0B,0xFD,0x0B,0xFE,0x0B,0x1B,
   0x0A,0x1B,0x0A,0x1C,0x0A,0x1C,0x0A,0x03,0xF2,0x0B,0xF3,0x0B,
   0xF4,0x0B,0xF5,0x0B,0xF6,0x0B,0xF7,0x0B,0xF9,0x0B,0xFA,0x0B,
   0x03,0xE9,0x0B,0xEA,0x0B,0xEB,0x0B,0xEC,0x0B,0xED,0x0B,0xEE,
   0x0B,0xEF,0x0B,0xF1,0x0B,0x03,0xDE,0x0B,0xDF,0x0B,0xE1,0x0B,
   0xE3,0x0B,0xE4,0x0B,0xE5,0x0B,0xE6,0x0B,0xE7,0x0B,0x03,0xD6,
   0x0B,0xD7,0x0B,0xD8,0x0B,0xD9,0x0B,0xDA,0x0B,0xDB,0x0B,0xDC,
   0x0B,0xDD,0x0B,0x03,0xCD,0x0B,0xCF,0x0B,0xD0,0x0B,0xD1,0x0B,
   0xD2,0x0B,0xD3,0x0B,0xD4,0x0B,0xD5,0x0B,0x03,0xC5,0x0B,0xC6,
   0x0B,0xC7,0x0B,0xC8,0x0B,0xC9,0x0B,0xCA,0x0B,0xCB,0x0B,0xCC,
   0x0B,0x03,0xBB,0x0B,0xBC,0x0B,0xBD,0x0B,0xBE,0x0B,0xBF,0x0B,
   0xC1,0x0B,0xC3,0x0B,0xC4,0x0B,0x03,0xB2,0x0B,0xB3,0x0B,0xB4,
   0x0B,0xB5,0x0B,0xB6,0x0B,0xB7,0x0B,0xB9,0x0B,0xBA,0x0B,0x03,
   0xA9,0x0B,0xAA,0x0B,0xAB,0x0B,0xAC,0x0B,0xAD,0x0B,0xAE,0x0B,
   0xAF,0x0B,0xB1,0x0B,0x03,0x9F,0x0B,0xA1,0x0B,0xA3,0x0B,0xA4,
   0x0B,0xA5,0x0B,0xA6,0x0B,0xA7,0x0B,0xA8,0x0B,0x03,0x92,0x0B,
   0x94,0x0B,0x99,0x0B,0x9A,0x0B,0x9B,0x0B,0x9C,0x0B,0x9D,0x0B,
   0x9E,0x0B,0x03,0x86,0x0B,0x87,0x0B,0x88,0x0B,0x8B,0x0B,0x8C,
   0x0B,0x8D,0x0B,0x8E,0x0B,0x91,0x0B,0x03,0x2F,0x0B,0x4F,0x0B,
   0x54,0x0B,0x5C,0x0B,0x71,0x0B,0x7B,0x0B,0x84,0x0B,0x85,0x0B
};
unsigned int BitMasks[] = {
   0x0000,0x0001,0x0003,0x0007,0x000F,0x001F,0x003F,0x007F,
   0x00FF,0x01FF,0x03FF,0x07FF,0x0FFF,0x1FFF,0x3FFF,0x7FFF
};

DLLIMPORT unsigned char __stdcall *GamePacketSize(unsigned char *data, unsigned int *size,
                             unsigned int *offset)
{
   unsigned int a;
   if (data[0] < 0xF0) {
       *size = data[0] - 1;
       *offset = 1;
       return &data[1];
   }
   a = (data[0] & 0xF) << 8;
   *size = a + data[1] - 2;
   *offset = 2;
   return &data[2];
}

DLLIMPORT int __stdcall GamePacketDecode(unsigned char *indata, unsigned int insize,
                    unsigned char *outdata, unsigned int outmax,
                    unsigned int *outsize)
{
   unsigned int a, b, c, d;
   unsigned int maxcnt, index, cnt;
   unsigned char *outptr, *inptr;
   int size;
   b = 0;
   size = insize;
   inptr = indata;
   maxcnt = outmax;
   outptr = outdata;
   cnt = 0x20;
   
   while (1) {
       if (cnt >= 0x8) {
           while (size > 0 && cnt >= 8) {
               cnt -= 0x8;
               size--;
               a = *inptr++ << cnt;
               b |= a;
           };
       }
       index = CharIndex[b >> 0x18];
       a = CharTable[index];
       d = (b >> (0x18 - a)) & BitMasks[a];
       c = CharTable[index + 2*d + 2];
       cnt += c;
       if (cnt > 0x20) {
           *outsize = outmax - maxcnt;
           return 1;
       }
       if (maxcnt-- == 0)
           return 0;
       a = CharTable[index + 2*d + 1];
       *outptr++ = (unsigned char)a;
       b <<= (c & 0xFF);
   }
   assert(0);
   return 0;
}



BOOL APIENTRY DllMain (HINSTANCE hInst     /* Library instance handle. */ ,
                       DWORD reason        /* Reason this function is being called. */ ,
                       LPVOID reserved     /* Not used. */ )
{
    switch (reason)
    {
      case DLL_PROCESS_ATTACH:
        break;

      case DLL_PROCESS_DETACH:
        break;

      case DLL_THREAD_ATTACH:
        break;

      case DLL_THREAD_DETACH:
        break;
    }

    /* Returns TRUE on success, FALSE on failure */
    return TRUE;
}


the h file:

Code Select Expand


#ifndef _DLL_H_
#define _DLL_H_

#if BUILDING_DLL
# define DLLIMPORT __declspec (dllexport)
#else /* Not BUILDING_DLL */
# define DLLIMPORT __declspec (dllimport)
#endif /* Not BUILDING_DLL */


//DLLIMPORT unsigned char *GamePacketSize (unsigned char);
//DLLIMPORT int GamePacketDecode (int);


#endif /* _DLL_H_ */


[Ringo]

In:

Code Select Expand


3F 1F 1C 30 02 10 52 1D 29 0A 85 D5 22 AB 8D 66 65 96 9E 88 59 B0 B0 07 97 C0 B8 9C 36 99 81 76 96 A9 0C 00 84 14 87 4E 04 4C C0 23 4F 44 2C D8 52 1C 80 01 38 02 B8 25 33 1B 9A 7A 21 66 C0


out:

Code Select Expand


03 00 8A 01 F2 AA B3 23 67 E4 95 67 47 01 72 0F 63 14 01 00 07 4B 00 05 6D 91 97 9E 3D 74 0F 9E 14 80 67 F2 AA B3 23 01 94 0F 71 14 01 00 07 4B 00 05 67 22 2F 3D 7B 01 AE 0F 75 14 01 00


That looks a good sign!
I'v only tested it with that packet and havent tryed running incoming data through it yet. looks like theres a few null terminated string in there tho!


Thanks to everyone who helped!
Mostly to laurion, thank you
Thanks to Brand.X for posting the code back in oct 2003.
Also thanks to MyndFyre, i will carry on trying to port it to VB in the not so distant future as i have your post to help me through it and can now 'see' the packets, so it should give me a bigger picture over time of how the decompression is fully working (and my head a rest)

I think there are a few others looking for d2 packet decompression as well, so i will put there dll here for them.
Iv also included a txt in the zip showing how to use the exports in VB6 to save people some trubble.

D2GS.dll

[Ringo]

Seems to crash when i try run large packets through it (like when on connecting to the game server)
Im thinking it might be a memery leek or somthing but im unsure.
Iv currently got it working by puting any packet over 15 bytes or under 100 through it and it seems to just about beable to hold out.

More of a warning to anyone that wants to use it.

The dll code is the same as the code posted 2 posts up and my calls to the dll in VB6 look somthing like this:

Code Select Expand


On Error Resume Next
Dim offset As Long
Dim Size As Long
Dim H1 As String
Dim H2 As Integer
Dim outdata As String
Dim maxsize As Long
Dim outsize As Long

H1 = GamePacketSize(data, Size, offset)
outdata = String(Size, vbNullChar)
H2 = GamePacketDecode(Mid(data, offset), Size, outdata, Len(outdata), outsize)


could anyone take a few min to scroll through the dll source (above) and check that im not missing anything, and that my calls in VB match those in the dll? i kinda tolk a guess int was refering to an integer and char was refering to a String, im hoping i havent got somthing silly like that mixed up but still unsure.

[Tazo]

Seems to crash when i try run large packets through it (like when on connecting to the game server)
Im thinking it might be a memery leek or somthing but im unsure.
Iv currently got it working by puting any packet over 15 bytes or under 100 through it and it seems to just about beable to hold out.

More of a warning to anyone that wants to use it.

The dll code is the same as the code posted 2 posts up and my calls to the dll in VB6 look somthing like this:

Code Select Expand


On Error Resume Next
Dim offset As Long
Dim Size As Long
Dim H1 As String
Dim H2 As Integer
Dim outdata As String
Dim maxsize As Long
Dim outsize As Long

H1 = GamePacketSize(data, Size, offset)
outdata = String(Size, vbNullChar)
H2 = GamePacketDecode(Mid(data, offset), Size, outdata, Len(outdata), outsize)


could anyone take a few min to scroll through the dll source (above) and check that im not missing anything, and that my calls in VB match those in the dll? i kinda tolk a guess int was refering to an integer and char was refering to a String, im hoping i havent got somthing silly like that mixed up but still unsure.

I think what Brand.X posted might be outdated, obsolete..?

[Ringo]

I think what Brand.X posted might be outdated, obsolete..?

Thats what i 1st thought, seems as mid 1.10 they introduced alot of new rune word items.
After some testing this after noon i found that it seems to be decompressing the packets ok:

Code Select Expand

Sent from D2 >
15 01 00 54 45 53 54 20 54 45 53 54 20 54 45 53    ...TEST TEST TES
54 20 54 45 53 54 20 54 45 53 54 20 54 45 53 54    T TEST TEST TEST
20 67 6F 74 20 49 74 3F 20 3B 29 00 00 00           got It? ;)...


Code Select Expand

Recv from my bot >
42 0F 1E BF C5 F2 8A B5 2A 86 D1 90 6C 14 C6 41    B.......*...l..A
CA 00 8A 02 D8 02 3B 00 45 01 6C 01 1D 80 22 80    ......;.E.l...".
B6 00 8E C0 11 40 5B 00 47 60 08 A0 2D 80 23 B0    .....@[.G`..-.#.
04 50 16 C0 11 DA 91 A4 6D 3B 15 C6 D1 40 EC 9A    .P......m;...@..
1F 40                                              .@

After decomression:
06 C9 01 00 02 00 00 00 00 00 5B 4C 69 67 68 74    ..........[Light
61 73 44 61 79 00 54 45 53 54 20 54 45 53 54 20    asDay.TEST TEST
54 45 53 54 20 54 45 53 54 20 54 45 53 54 20 54    TEST TEST TEST T
45 53 54 20 67 6F 74 20 49 74 3F 20 3B 00 00 00    EST got It? ;...
00                                                 .


The problem seems to be when its in the middle of decompressing a packet and another 1 gets put into the function, it causes VB6 to generate a error report.

After linking data to a command click sub and holding down the enter key, i did notice my cpu useage go up a fair bit but VB6 didnt crash for some reassion.

Im pritty sure its a memery leek somwhere in the dll thats causeing the slow decompression to take place but im not sure where i should be looking in the dll to try fix it, if thats where the problem is.

Also if i dont use 'On Erorr Resume Next' when calling the functions in VB6, i get a run time error '7' out of memery.

Im right out of ideas on this one

[Tazo]

...The problem seems to be when its in the middle of decompressing a packet and another 1 gets put into the function, it causes VB6 to generate a error report.

Create a queue type of thing. Add a listview to your form, or create an array. Everytime new data is received, add it to the array or listview. Create a timer that fires every second, or whatever, and decompress the first item, and remove it. That would solve that problem (if that is your problem, what you said in the quote).