Proxomitron reduces RWIN to 32768

[laighleas]

z12 Wrote:

Peakaboo Wrote:the fallacy is assuming something will not have an impact if you are truly guessing as to what the problem is - which despite all the expertise is what is going on.

I agree. Guessing wasn't getting it done, so I decided to disassemble proxo's code and have a look for myself.

I hoped someone would. :-) I don't have the expertise to do that, unfortunately, otherwise I'd have had a peek under the hood a while back. It seemed to be the only way of resolving the issue.

z12 Wrote:Based on the code, its clear that there is a setsockopt function call that hard codes 32768 for the rcv buffer size. Why this function call has no effect on pre XP OS's, I can only guess.

Well, as I mentioned above, the default RWINs for Win9x and NT are given as 8760 and for Me/2k 17520, all of which are less than Proxomitron's setting of 32768. So it wouldn't be a problem. In addition, XP introduced a dynamic RWIN and windows scaling so you could have very large RWINs suitable for broadband.

z12 Wrote:However, I can change the rcv buffer size to whatever I want by editing the hard coded value. Currently my rwin is 513920 as reported by speedguide and verifed with ethereal.

That's brilliant. :-) So how do you go about it? Step by step. Including how to dissassemble the code.

z12 Wrote:BTW, thats with my filter set.

Kevin

[Guest]

Oddysey Wrote:Well, for criminy's sake, share the dope with the rest of us!

:-)

Oddysey Wrote:Can you at least give us the byte offset where the new value must be placed (in the exe file)? And what would that new value be, hmmmm? Also, can we use something like Resource Hacker, or do we have to get down and dirty with Debug, in the command line environment?

Well, that's starting to get into areas of which I am ignorant. That said, Resource Hacker hacks resources, for example icons. If the buffer doesn't count as a resource, you can't use Resource Hacker.

[quote="Oddysey"]P.S. Nice going!

A very nice piece of work :-)

Kevin

[Oddysey]

So maybe this should be addressed to z12???

Mike, are you gonna spill the skinny, or do we have to administer some 'tough love' here?

A byte offset is all that I need, I know how to use a debugger, but it's a sure bet that not everyone here is in that same boat. If you can, please outline what to do at the neophyte level. If you can't (or don't have time, or whatever.....), just give me the raw data, and I'll run with the ball.


Oddysey

[Kye-U]

Oddysey Wrote:Mike, are you gonna spill the skinny, or do we have to administer some 'tough love' here?

*cough cough*

[z12]

I'm not the only one working on this, so I don't want to jump the gun with a preliminary announcement.

However, I'm sure that an annoucement about the tweak you can make to proxo to resolve this issue is forthcoming.

Mike

[Kye-U]

I understand

Take your time with this, because I know how hard hex modification is

[laighleas]

How's this going? Anyone had any success with it?

Kevin

[JJoe]

Sorry the review took us so long.
But I think most people will understand.

Patches are at

http:// rapidshare.de/files/8168374/N45RWIN.zip.html

Evidently rapidshare.de changed the 45 day policy and deleted the file.

For now, N45RWIN.zip has been uploaded to
http://rapidshare.com/files/10951026/N45RWIN.zip

Click the "Free" button on the rapidshare.de page to go to the download page.

JJoe


N45RWIN.zip ReadMe is:

Quote:***********************The Problem*******************************************
If you are reading this then you probably know that Proxomitron can set RWIN to 32768.
http://prxbx.com/forums/viewtopic.php?t=641
http://groups.yahoo.com/group/prox-list/message/22257

To test your Operating System, go to http://www.speedguide.net/analyzer.php
Check the value of RWIN, with and without using Proxomitron.

Windows XP SP2 or Server 2003 with Proxomitron probably show 32768.
Windows 95, 98, 98SE, or 2000 with Proxomitron probably do not.
When Proxomitron uses another local proxy like
Browser -->Proxomitron-->Proxy-->ISP
the "correct" RWIN is probably shown.

***********************The Patches*******************************************
There are patches that may return control of RWIN to Windows at
http://wind.prohosting.com/proxmine/cgi-bin/uploader/ .
Our Japanese friends have been using them for approximately a year.
A translation of the ReadMe in PmU_0341.zip is below.

N45jRWIN.exe and N45mRWIN.exe use the same method the Japanese patches use.
They also add a disclaimer to Proxomitron's "About" screen.

To install a patch:
Make a backup copy of the Proxomitron exe.
Execute N45jRWIN.exe to alter the *June* version of Proxomitron Naoko 4.5.
Execute N45mRWIN.exe to alter the *May* version of Proxomitron Naoko 4.5.
Visit the "About" screen and verify the info.

Report problems caused by the patch to your favorite Proxomitron forum or the Prox-List.
Guest posts are allowed at http://prxbx.com/forums/index.php

***********************Explanation********************************************
[Letter has been edited]
Hi,

I'm count_b, the webmaster of Proxomitron-J.

jjoe bugg <jjoebugg@> wrote:

> Hi,
>
> I am jjoebugg of the Prox-List, http://groups.yahoo.com/group/prox-list/ .
>
> XP SP2 limits RWIN to 32768.
>
> Does the Proxomitron RWIN Patch at
> http://wind.prohosting.com/proxmine/cgi-...U_0341.zip
> fix this?

I read the readme.txt and checked the referred article on a Japanese BBS.
They said it fixes the RWIN limit.
http://web.archive.org/web/2004113021481...092672987/

This is the patched address...

*Naoko 4.5 June
FILENAME Proxomitron.exe
0000D581: 04

*Naoko 4.5 May
FILENAME Proxomitron.exe
0000D521: 04

In detail they said this patch changes the argument of SetSockOpt.
Original Proxomitron uses this value...
nOptionLen : 04

And this patch changes...
nOptionLen : 00

I am not programmer so I don't know what that means.

> Can it be used on the original exe?

Yes. But the exe filename should be "Proxomitron.exe"

> Who is the author?

That is anonymous BBS so I can't find out who the author is.

Thanks,
count_b
[/Letter]

The SetSockOpt command can be used to set the "receive window size" on a per-socket basis.
For reasons still unknown, the command does that on some but not all Windows systems.
Setting nOptionLen to 0 nullifies the socket option and returns control of RWIN to Windows.

***********************A Request*********************************************
Everybody should be very careful. Proxomitron is not our program.
If a patched exe got loose and caused trouble, Scott would likely catch the blame.
Do not share or distribute patched EXEs.

http://groups.yahoo.com/group/prox-list/message/16401
From: "srl_list" <srl_list@...>
Date: Thu Jul 3, 2003 3:08 pm
Subject: Modified versions of Proxomitron
Modified versions of Proxomitron are explicitly NOT permitted to be
distributed according to it's license.

Regards,

Scott

***********************PmU_0341.zip ReadMe*********************************
[Translation]
These executable files apply the patch of 509 person in
Proxomitron Part23 at
http://pc5.2ch.net/test/read.cgi/win/1092672987/

For Proxomitron Naoko 4.5 June, use PatN45June.exe
For Proxomitron Naoko 4.5 May, use PatN45May.exe

After copying to the folder where Proxomitron is installed please execute.
[/Translation]

To see the 509th post in Proxomitron Part23 use:
http://web.archive.org/web/2004113021481...092672987/

--

This post was last modified: Jan. 09, 2007 by JJoe.

[laighleas]

JJoe Wrote:Patches are at

http://rapidshare.de/files/8168374/N45RWIN.zip.html

Hmm! Slight problem - though I'm using the right patch (June), it reports that the Proxomitron version is unknown. May be because I've used the earlier patcher by (I think) Henke (Proxo45j-Patcher.exe), plus I changed the icons with Resource Patcher (didn't like the new ones). So at present, doesn't look if I can use it. :-( Any suggestions?

Kevin

[Kye-U]

I experience this too, since I too use Henk's ProxoPatch. Perhaps a Seek-and-Replace method patch can be made, so it's more generic? Perhaps I can work on a quick one.

[Siamesecat]

Quote:right patch (June), it reports that the Proxomitron version is unknown. May be because I've used the earlier patcher by (I think) Henke (Proxo45j-Patcher.exe), plus I changed the icons with Resource Patcher

The reverse does not work either. I patched the original Proxomitron.exe with the RWIN patcher, then tried to use Proxopatcher. It complained that the version was unknown.

[JJoe]

The patches require original EXEs.
Henk's do to.

For now, I suggest people with patched EXEs use a Hex Editor to change the byte. Think of it as an adventure. ;-)

I think the address of the byte that needs to be changed is the same.
But you should compare the code around the byte in the original exe with that of the ProxoPatchered exe *before* you go changing just any 4.

Then it would be nice to add a warning to the "About" screen with a Resource Editor. Henk has one there but he just altered the resources. You have altered the program.

Maybe:
The byte at 0xd581 has been changed to 0. It was 4.
Without this change, RWIN may be locked at 32768.

I think that people who patch programs have a responsibility to protect the authors of the programs they patch. Just my opinion.

Somebody may put some more patches up for the less adventurous.
People who have changed the exe with a Resource Editor will likely need to start fresh or use a Hex Editor, tho.

--
JJoe

[Peakaboo]

JJoe Wrote:The patches require original EXEs.
Henk's do to.

For now, I suggest people with patched EXEs use a Hex Editor to change the byte...

Then it would be nice to add a warning to the "About" screen with a Resource Editor. Henk has one there but he just altered the resources. You have altered the program.

I think that people who patch programs have a responsibility to protect the authors of the programs they patch. Just my opinion.

Somebody may put some more patches up for the less adventurous.

--
JJoe

Good job to all who worked on this.

I did not have the problem since not on xp sp2 but wanted to see if I could hexedit based on the info provided.

Having no experience with this it took me a few trials to get it but I finally did. The hard part was finding the corresponding byte in the version of proxo I was using 4.3. Finally found it I think @ c101.

It might be my imagination but after making the hexedit change, and firing up the edited version, web pages seem to be loading quicker - further testing on this...

Also the patch provided does what it says it will do on the original 4.5j version which I dld for testing. I did not try the may version patch.
Can't tell if it fixes anything since I never had the problem... not using xp

Anyway just thought I'd say atta boyz ngals if applic.

Finally, I agree with you on duty of those who alter the program - to make a notation and to not distribute the altered exe. This is the least we can do in memory of SRL.

[Kye-U]

I've finished a seek and replace patcher that works with 4.1 to 4.5j.

Quote:It has been tested on and proven to work with:

4.1
4.2
4.3
4.4
4.5m
4.5j
4.5j Patched with ProxoPatch v3.0 by Henk
4.5j Patched with ProxoPatch v4.0 by Henk

Download it here:

http://74.53.146.215/paFileDB/pafiledb.p...file&id=72

Please note that I have added an license agreement requirement

JJoe and z12, let me know if there's anything you want me to add/change/remove in the patcher. I'd be happy to make any changes.

[JJoe]

Peakaboo Wrote:Having no experience with this it took me a few trials to get it but I finally did. The hard part was finding the corresponding byte in the version of proxo I was using 4.3. Finally found it I think @ c101.

It might be my imagination but after making the hexedit change, and firing up the edited version, web pages seem to be loading quicker - further testing on this...

Finally, I agree with you on duty of those who alter the program - to make a notation and to not distribute the altered exe. This is the least we can do in memory of SRL.

Umm. I appreciate the enthusiasm but you might want to change that back. ;-)

I think that part of 4.3 has something to do with text display.
I'm not sure what you are looking for is in 4.3.

Take a look at 4.5 june instead.
Starting at d57c you should see
00 80 00 00 6a 04
the 04 is what you would change to 00
00 80 00 00 is the 32768 part.
You can find the same string in the Proxopatchered 4.5 EXEs.

Changing the value is easy.
Adding the disclaimer is a little more... adventurous.
But a big part of Proxomitron is learning.

Have fun,
--
JJoe