IDA Pro Basic (Instruction of IDA )

Twix

Twix

Advance Member
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02/26/15
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Here is a good tutorial for anyone who is willing to learn what the arm assembly language is and how do you understand it.
This is a very useful tutorial to understand the basic instructions in IDA


Steps of doing:

1. Check the Game --> What could be hacked? What names the functions could have?

2. Load the Binary(lib file in lib folder) in IDA -->Check if load resources is checked

3. Let the IDA time to load

4. After that open up a Hexeditor and put the Binary in it

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Useful searches:

(the big ones are the key words)


Player's Life: life,health,damage,hp,live,power

e.g: CSoldierHero::takeDamage
e.g: CPlayer::removeHealth

Points: points,score,mp

e.g: Game::UpdatePoints
e.g: Game::AddPoints
e.g: Game::loadScore

Ammo: ammo,shoot,shot,fire,weapon

e.g CPlayer::processShooting
e.g CPlayer::fire
e.g xxx:Link DeadubAmmo

If you have other things like 'speed' or 'suns' or something just try different options

Extras:

-level -->level up cheats
-powerups -->megajump,doodlejump
-some keywords depend on the game.. rpg,action,fun,...
-kill -->splinter cell
-Unlock --> Unlock is an important keyword *

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WHAT TO DO...?

ADD(e.g score): set to MOV R0,#480000000*
set the registers or the value after #xx to very high

SUB(e.g ammo): change to ADD,NOP it. Or set the SUB to #0

RSB(reverse subtract --take damage): NOP it or set the registers to low or try to change to an ADD

LDR(e.g score,...): change the Register to Register 7(R7) or to an MOV R0,#480000000*

STR(e.g setLife): Change the register to R7 or MOV R0,#480000000*

SUBS/ADDS (same like SUB and ADD)

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CODES:

ADD R3,R3 #1 -->01 30 83 E2
SUB R3,R3 #1 --> 01 30 43 E2

ADD R1,R3,R3 --> 01 30 83 E0
SUB R1,R3,R3 --> 01 30 43 E0

MOV R0,#48000000 = 12 03 A0 E3 -->very high value (you know the PvZ Hack where the sun turns into 9999? thats a MOV R0, #48000000)

MOV R0,#1 = 01 00 A0 E3 (often used for functions like : isXXX or hasXXX (e.g: player::hasAllWeapons if you use an MOV R0,#1 it always returns the value 1 so you have all Weapons))

MOV R0,#0 = 00 00 A0 E3 (often used for isXXX and hasXXX functions(e.g: player::needFood if you use MOV R0,#0 it always returns 0 , so you do not need food))

2Byte BX LR : 7047 -->deletes a function
2Byte Nop : C046 -->NOP = No operation

4Byte BX LR : 1EFF2FE1 -->deletes a function
4Byte Nop : 0000A0E1 -->NOP = No operation

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Branches:

Above mostly all Branch commands there have to be a CMP(compare) and because of this CMP it branches

e.g: BEQ(branch if equal) above: CMP R3,R2

so it doesnt branch because R3 not equal to R2

if CMP R2,R2 and then BEQ then it branches



BEQ = Branch if equal (cmp r2,r2)
BNE = Branch if not equal (cmp r3,r11)
BLT = Branch if lower than(cmp r2,r3)
BGT = Branch if greater than(cmp r3,r1)


_______________________________________________________



ONE SENTENCE IS IMPORTANT: "try it!"

Without trying you can't succeed.

So go ahead and try!

Plist editing - Hex editing - IDA Hacking

Plist: Just download some Games and rehack plists

Hex: Download savefile and Compare and learn with it some hex.

IDA: 1. Use the Offset DB and go with IDA to the Location. Check the function and what was changed. 2. Download some Binarys and Compare them. 3. Read Tutorials

My knowledge:

BX LR - NOP - SUB - ADD - LDR - STR - MOV - RSB


Just one last Thing: GDB isnt the horror. I dont like GDB. I can't work with it.

I just sometimes use it for checking a functions and their registers(e.g when I don't know what registers are low in there and what high).


Unlock:

In Brothers in Arm: Hour of Heroes

CSoldierHero UnlockAllWeapons

Double click on it..

Make an XRef from the Ttle of the function (highlight the function and press X)

Then there should be an BNE(branch not equal) it branches if not equal

If you change it to and B(branch no conditions) it always branches and you have your weapons unlocked..

This means yo can't change the function directly.. you have to check from where it comes

BNE,BLT,BGT,BEQ --> B = Change the last byte to an EA if it is 4 Byte XX XX XX EA
BNE,BLT,BGT,BEQ --> B = Change the last byte to an E0 if it is 2 Byte XX E0



CMP

If you hack ammo and you know there is a SUB Rx, Rx #1 which sumtracts your ammo the look above there should be a CMP.
If there is a CMP which compares thesame register as the SUB subtracts then you are right and it could be the CMP that compares if Rx = 0

IF Rx = 0 it reloads your gun

so if you NOP (0100A0E1) the CMP it doesnt reload as it doesnt compare if Rx is equal 0



You often find CMPs above Branches. This means you have two options: Either you make the BXX to only aB so it branches all the time(look at branches). Or you set the CMP as neede: e.g:

BNE(BranchNotEqual) so it branches when the comparison result isnt equal --> CMP R2,R3 if R2 and R3 have different values it branches as they aren't equal

ALL CREDITS TO HACKJACK I DID NOT MAKE THIS TUTORIAL

For more info you can go here Link For Detailed Info
 
but that program ? you do not say that file. I take saw there there are 4 or 3 and then to the lib folder there are 2 types x86 folders ie not explain anything and then when loading a file . I know I remain the loadIng
 
iAlex said:
try searching on yt ... there a lot of videos about idahacking ... and some of tme are really interesting ;)
Click to expand...

The only videos I find on IDA hacking on yt are indians that talk wayyyy too fast for me to even try to comprehend. Noobs like me could really learn from a video of slow step-by-step instructions and detail about what's going on.... Boy that would be nice.

Could you possibly link me to one Please?
 
Androhacks_ said:
The only videos I find on IDA hacking on yt are indians that talk wayyyy too fast for me to even try to comprehend. Noobs like me could really learn from a video of slow step-by-step instructions and detail about what's going on.... Boy that would be nice.

Could you possibly link me to one Please?
Click to expand...
Im talking about the indians guys ... they are really good with it
 
Sorry if this bothers anyone, I was wondering if anyone could explain what this function does exactly
Code: 
CMP          R1, #0
STMFD     SP!, {R4,LR}
MOV         R4, R0
BLT           (some other script that's not important at the moment)
I mostly understand what each command does independently, I'm just trying to make sense of how they interact with each other in this example.
 
andytoro said:
Well, nothing much from your code... but you need to understand basic how machine works. If you want to fully understand what it means, I would recommend you to read about machine stacks (on your snippet code it's using full descending which is the default one for ARM). Then you need to know what is register, link register, r15 (PC) and how they work. A bit of programming skill would very beneficial for your study.
Trust me, anyone here whom understand these code can explain what it means, but if you really want to understand interaction between register, then you need some experiment and self study.
I don't know if you have understand / have basic programming or not. But if not (I'm not belittle or underestimate you in here), then here is my recommendation to understand the basic: ARM subroutines & program stack
Click to expand...
Thanks for the resource! I do actually have quite a lot of programming experience in several fields (nearly all web languages, I'm a web design consultant and python, C some C++ and C#) and to me, ARM seems rather similar to C which is probably what's tripping me up :)
 
a videotutorial wood be nice , explained .. in the smallest detailes .for example show us how to mod damage and hp ,how to make x10 damage x10 defense stuff like this, if you wanna help newbies you should do it
 
@Twix

Might I ask a question? I know the thread is old, but the thread is what made me learn what little I have and is the only place I could turn to. :flushed:

I am modding a game and so far I have successfully altered the currency to always stay at obscenely high values (THANK YOU for this guide!), but moving onto skill points, I can't for the life of me get it to work. I found the Function the skill is associated to and then found the HEX that changes it (took forever), however, no matter how I set MOV R0, #xxxx it ALWAYS returns IN GAME as 0, which makes it impossible to gain skill points as well.

Any idea what I can try to change? There are MOVs, ANDs, CMPs, BLSs, BICs, SUBEQs and at the end, a BX LR. :sweatsmile:
 
Rhaes said:
@Twix

Might I ask a question? I know the thread is old, but the thread is what made me learn what little I have and is the only place I could turn to. :flushed:

I am modding a game and so far I have successfully altered the currency to always stay at obscenely high values (THANK YOU for this guide!), but moving onto skill points, I can't for the life of me get it to work. I found the Function the skill is associated to and then found the HEX that changes it (took forever), however, no matter how I set MOV R0, #xxxx it ALWAYS returns IN GAME as 0, which makes it impossible to gain skill points as well.

Any idea what I can try to change? There are MOVs, ANDs, CMPs, BLSs, BICs, SUBEQs and at the end, a BX LR. :sweatsmile:
Click to expand...
I apperciate your comment well but i dont have much experince for IDA BASICA or how to modding using it only reflector or dnspy :D that i can use them this day :D
thanks in advance
hope other's team can answer your question
 
Twix said:
I apperciate your comment well but i dont have much experince for IDA BASICA or how to modding using it only reflector or dnspy :D that i can use them this day :D
thanks in advance
hope other's team can answer your question
Click to expand...

Oh, okay! I just assumed. ahaha probably shouldn't have. Thank you anyway for taking the time to reply with this. :)

And if someone is willing to help me out here, I'd greatly appreciate. I've been stuck on this particular Function for about three days now. :tired:

Thanks again! (y)
 
Rhaes said:
Oh, okay! I just assumed. ahaha probably shouldn't have. Thank you anyway for taking the time to reply with this. :)

And if someone is willing to help me out here, I'd greatly appreciate. I've been stuck on this particular Function for about three days now. :tired:

Thanks again! (y)
Click to expand...
may be @icry4u @DaiCaVN @iAlex
hope one of them can helps you
 
Rhaes said:
@Twix

Might I ask a question? I know the thread is old, but the thread is what made me learn what little I have and is the only place I could turn to. :flushed:

I am modding a game and so far I have successfully altered the currency to always stay at obscenely high values (THANK YOU for this guide!), but moving onto skill points, I can't for the life of me get it to work. I found the Function the skill is associated to and then found the HEX that changes it (took forever), however, no matter how I set MOV R0, #xxxx it ALWAYS returns IN GAME as 0, which makes it impossible to gain skill points as well.

Any idea what I can try to change? There are MOVs, ANDs, CMPs, BLSs, BICs, SUBEQs and at the end, a BX LR. :sweatsmile:
Click to expand...
it could be that the skill points are floats and you're returning integer
 
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