Questions tagged [assembly]
A family of very low-level programming languages, just above machine code, where each statement corresponds to a single machine code instruction.
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Why would a compiler generate such useless wrapper functions?
I am starring at a lot of assembly code for the Espressig ESP32 (Tensilica/Cadence Xtensa LX6 core) recently and I've been asking myself why I see a lot of functions which look like the following:
...
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HASP-HL in old Fun4Four Software
I got this today for ya guys https://mega.nz/file/ydU10BqA#VF87e1GJ0ls0LybkK-piQcvsgu_UrZE_6wJPfmIdQps
^^
To clarify for those panicking about Copyright or anything: This specific system is not being ...
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Immobilizer Logic of Specific ECU
I am working on a project . Its Suzuki Wagon R 2010 ECU of 33910-82kf Part no
This ecu Immobilizer works on CAN System ECU (Chellanger) BCM (Responser)
Ecu send 8 bytes message on 0xD1 CAN ID and BCM ...
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Help Needed with extracting Image Data from DOS Games Query
I need help with Extracting Aircraft Sprites, from some WW2 DOS Games. A code in C Program Language
was written for me, a while ago and it extracts the Bitmap Images that makeup various .PAC Files in ...
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How could a CRC-15 CAN be transformed into 8 bytes in an embedded system?
I am analyzing calibration binary files of an embedded system (BMS) that likely uses a CRC-15 CAN checksum.
From my firmware and bootloader file analysis, I have found a PECLookup table, which ...
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Optimize VAX instruction with IDA microcode
I learning microcode, and i tried to use microavx plugin, it always catch Internal ERROR 50757
I also try to code a small plugin, but got same error when run emit() function
import ida_ua
import ...
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What is CARRY2 in Ghidra?
I decompiled a 16-bit Windows 3.1 program with Ghidra 11.0.3 and part of it looks like this:
if ((uVar6 = local_8 + local_a + 0xa46b, uVar6 + local_10 == -0xded &&
((uint)CARRY2(local_8,...
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Strange SBB behaviour
I have a code in which I have:
EAX=00002c36
and after:
SBB eax, 0
the eax turns:
EAX=00002c35
Is that possible?
Shouldn't eax be the same value?
If it's correct, it seems like I don't really ...
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imul instruction with three operands
I want to use a imul instruction with 3 operands. Is the destination operand the first or last? I searched the web and got contradictory informations.
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What is the "Fallthrough" option in Ghidra for?
If you right-click on the assembly window in Ghidra, one of the last options shown will be "Fallthrough":
Can someone explain in plain English what is that option for?
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Offset addressing
I’m writing a C-SKY (CK803S) processor module for IDA Pro, and a question arose about offsets in transitions, small ones are fine, but long ones lead to nowhere, from the documentation:
in code I ...
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Searching for a byte pattern and then hooking all instances of it using frida on iOS
I'm using a frida script to scan for a certain byte pattern when I launch an iOS app.
I can log each offset and confirm these are correct by also printing out the instructions at those locations and ...
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Mnemonic suffixes for x86-64 assembly for AT&T syntax
I'm trying to understand suffixes used for the AT&T syntax for the x64 assembly used for instruction mnemonics.
For regular cases:
'b', // 8_bit
'w', // 16_bit
'l', // 32_bit
'q', /...
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Is DOS Assembly Hexadecimal Different To Modern Hex Editor Hexadecimal?
I am trying to find the correct Data Segment, corresponding to a certain File in a 16bit DOS Game.
The Assembly Instructions for the Decompiled .exe File in IDA Pro Version 5, I am looking at.
I was ...
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Keystone rust bindings error when assembling "syscall; ret" shellcode
I'm working on a project related to Process Injection for learning Rust. I have to inject shellcode at some points and use the Keystone engine for assembling shellcode from source.
I detected that the ...
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How to run exe program loaded into IDA Pro or Ghidra
I'm new to reverse engineering, just learning. After the exe program is loaded into IDA or Ghidra, how do I run the exe program that loaded into IDA/Ghidra? so I can interact with the exe program? and ...
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MS DOS development - Interrupt controller
cseg01:0005229A mov dx, 21h ; '!'
cseg01:0005229E in al, dx ; Interrupt controller, 8259A.
cseg01:0005229F or al, 1
cseg01:...
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from executable to assembly source code?
let's say i have an ".exe program" and i want to disassemble it and get "disassembled code" .
my question is => can i maintain and organize that "disassembled code" ...
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Assembly for malware analysis
I know we have some architectures for assembly language. But I wanna know this: I need learn x86 assembly ? , or arm assembly ? , or both ? , or others ?..
Please help me , what should I learn?
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Help Needed With Finding Image Data In DOS Game File
I have been analysing, an File called FW190AS.PAC from a 16 Bit Game called Secret Weapons Of The Luftwaffe, in a Hex Editor, the Bytes are displayed in Little Endian format. My aim with this game, is ...
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Reversing Assembly to C
I've read the open letter addressing students asking for help with their homework and I agree with it, therefore I will try to be less of a pain in the *** ;)
I need to reverse the x86-64 (AT&T) ...
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How can you tell where an assembly function ends?
Finding the start of a function is sometimes obvious - for example if some part of the code has a call foo then foo must be a function.
But what about finding the end of a function? I realize tools ...
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Change string value when string is in a RAM address x64 c++ program
I'm new to reverse engineering.
I'm simply trying to change the value of a string in x64dbg, of a program I make myself in VS
(It's a c++ program, and is VERY simple; it just prints a string, and two ...
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Reverse engineer a blackbox function operating on single or double precision floats for emulation
I own and run a NEC VectorEngine 10C which is a PCIe accelerator running a proprietary ISA which has many fun instructions among them is VRSQRT which computes an approximation of the inverse ...
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What are the prerequisite knowledge needed to start solving crackmes?
I started by reading a book on C language and then moved on to "Programming From Ground Up," which teaches basic programming in x86.
School just ended, I'm working on cracking a game called ...
