forums.ps2dev.org

[bubugian]

Hi all,
I'm new with psp programming so, please be patient if my questions are banal.

In some posts I found some reference to NID.
Seems that NID is used for hooking sce function.

I'm not sure to have understood so, I'm going to post some simple answer:

- What is NID ?
- Where is NID (how I discover it, with wich tools) ?
- Why I shoud hook a sce function ?
- How I coul hook a function ?

Thanks all !

[slasher2661996]

Q1: Well, a nid is the memory address 0x000000 etc. to a reference to a firmware function

Q2: http://silverspring.lan.st/

Q3: You should hook a function is you want to track the usage, do something before the function executes etc.

Q4: Search this forum "easy hook example"

[m0skit0]

Q1: A NID is just a 32-bits function ID for the kernel to recognize it and resolve it on the ELF imports. It's the SHA1 hash for the function name. Each NID is unique (hopefuly) and it's related to an export library, which in turn is related to PRX modules.
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[slasher2661996]

[Dariusc123456]

[m0skit0]

I think you meant only some functions got their NID randomized. You can try this links to see what i'm saying:

Function name & NID for 5.00 FW:
http://prxlibdocs.dark-alex.org/5.00/index.html

Online SHA1 calculator
http://sha1-hash-online.waraxe.us/

Take any resolved function name (that is, things like sceUsbBus_driver_48CCE3C1 are just library name + NID and not the real function name, so it doesnt work), put it in the text box, click "calculate hash" button and compare first 4 bytes of hash to function's NID in reverse order: compare first byte of hash with last byte of NID and so on.

Let me know when you find one that doesn't coincide.
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[J.F.]

All NIDs used to be just the SHA1 hash of the function name... emphasis on used to be. User functions still are since Sony clearly can't change the user functions. However, in an effort to defeat custom firmware, Sony started randomizing the kernel function NIDs starting at 3.70. Not all kernel functions either, just many of the ones custom firmware relies on.

So user function NIDs will still match the SHA1 hash of the name, but many of the kernel function NIDs won't.

[Dariusc123456]

Could it be possible that Sony is using the sha-1 but added on some random numbers to confuse cfw/homebrew developers?
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PSHN - Playstation Hacking Network
PSX/PS1 - HACK - Game Shark
PS2 - HACK - Swap
PSP - HACK - Pandora
PS3 - ?

[Jim]

You think?! Genius!
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http://www.dbfinteractive.com