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Bogus, posted Sat May 04, 2019 4:01 pm (47593)

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Hello aluigi, can you add kl4e compression to quickbms?
Jpcsp emulator in newest revisions can install 6.61 firmware update, eboot.pbp file and even decrypt some prx files with prxdecrypter but not decompress.
Code for kl4e compression is in prxdecrypter and psardumper source code.
I not have own psp, i cannot share file publicly, only via pm, because is part firmware and is copyrighted.
Sorry if topic is in wrong place.
edit:
here is link to prxdecrypter source code, contain kl4e compression
https://github.com/smiky/psptools/tree/ ... XDecrypter
aluigi, can you enable allow users to send you private messages?
I want send file to you for analysing.

aluigi, posted Sat Jun 01, 2019 8:22 pm (48246)

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As far as I know all the compressions used there are just wrappers for sceKernelExtendKernelStack which is part of pspsdk (closed source?).

Regarding the private messages, eh no sorry I have no time to handle them.
If it's something urgent you can use the email but for this type of stuff I ever tell people to use zenhax.

Bogus, posted Wed Jun 05, 2019 2:20 pm (48487)

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I checked on google, this system call is in open source pspsdk.
File i can send via email, only i not know, whether you understand this file format.
Jpcsp support kl4e, but with other attribute.

aluigi, posted Wed Jun 05, 2019 2:22 pm (48488)

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Are you really sure that pspsdk is open source?
If that's true it would be easy for you to find the compression source code and share it with the forum.

Bogus, posted Wed Jun 05, 2019 2:53 pm (48490)

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yes:
https://github.com/smiky/psptools
PRXDecrypter folder
Unofficial pspsdk is open source, only official sony is proprietary.
eg. Minimalist PSPSDK, devkitPro.
Kl4e is part kirk encryption
What you have email, [email protected] not working?
edit:
I already know, [email protected]

aluigi, posted Wed Jun 05, 2019 4:06 pm (48491)

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That's only a wrapper. No compression code.

Email works well and I received your files.
kirk is already available in quickbms but now you are talking about encryption, and not compression.

Sorry but I have no time so if you have the full source code of the function to share I have no problem to implement it in quickbms.

Bogus, posted Wed Jun 05, 2019 4:31 pm (48494)

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pspsdk source code:
https://github.com/pspdev/pspsdk
Maybe this?

aluigi, posted Wed Jun 05, 2019 7:33 pm (48496)

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Again... that's a wrapper because kl4e and lzrc are closed source built inside the PSP firmware.

Feel free to search 0x6C6887EE online.

There is an open source reverse engineered firmware which is in MIPS assembly:
https://github.com/uofw/uofw/blob/maste ... em/start.S

Feel free to make a working C code from that assembly.

Bogus, posted Wed Jun 05, 2019 9:20 pm (48500)

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I know, this functions are only, what psp kernel do.
I'm not good in programming.