Questions tagged [functions]
A sequence of instructions performing a basic task packaged as a unit in a program.
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Function return in machine code (by platform/compiler)
I am asking this question to gather a knowledge base. I know in x86-64, a machine code function can have only one function return, i.e., ret instruction. I know it can be compiler (GCC, clang, etc) ...
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Cutter shows addresses relative to stack but not rbp. How to change it?
Look at the first image:
Here what I get is var void *buf @ stack - 0x28.
But I'm watching a tutorial there his Cutter shows like this:
var void *buf @ rbp - 0x20. How can I change cutter to appear ...
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Log functions called in IDA Pro?
When I run an exe in IDA how could I log which functions were called into a text file?
log.txt:
call func1
call func2
call func1
call func1
Not worried about indirect calls.
This is for differential ...
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2
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How can I jump to the start/end of a function in x64dbg?
I'm currently debugging a program using x64dbg, and I'm wondering how to quickly jump to the start or end (prologue/epilogue) of a function while I'm in the middle of it. I couldn't find this ...
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split function argument from IDA's hints
Suppose I have a function, I know that the first 4 arguments come with fixed registers.
_BYTE *__fastcall foo(__int64 a1, _QWORD *a2, unsigned int a3, char a4, _QWORD *a5)
For the fifth one, if I ...
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which command in windbg to use to display the struct in function argument
The struct looks like this.
typedef struct _RTL_DYNAMIC_HASH_TABLE_ENUMERATOR {
struct _RTL_DYNAMIC_HASH_TABLE_ENTRY HashEntry;
struct _LIST_ENTRY* CurEntry;
struct _LIST_ENTRY* ChainHead;
ULONG ...
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How to reverse an import function?
I'm reversing windows .sys file and an import function RtlLookupEntryHashTable appears in my target functions. I want to know the pseudocode of it. How to achieve this?
.text:00000001C00218C2 ...
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How to speed up finding a function from pseudocode in IDA?
I have a function with the pseudocode of
__int64 __fastcall sub_7FF7067A01F0(__int64 a1, __int64 a2, unsigned int a3)
{
if ( qword_7FF709F91498 )
return (*(__int64 (__fastcall **)(ID2D1Geometry *...
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Calling a function with a variable number of args from a proxy DLL
The program I'm messing with has builtin logging. Using a proxy DLL, I managed to activate it by calling the right functions from the real DLL. However, I got stuck at using the actual logging ...
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How to define "code" variable type in Ghidra
Of all the confusing parts of Ghidra, I'd like to ask about the "code" keyword. A similar question was asked here. However, I am not asking what the keyword is, but how to interpret/define ...
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I don't find the body of a function that I called in the main function
I have created a very simple x86 console program that uses Visual Studio 2019 compiler to sum 2 numbers just to see how is the program be after disassembly but I found something unclear to me.
// C++
#...
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How do I find a function and find out what it does using reverse engineering?
I am attempting to find a function in a specific game. Is there any way that, using the assembly code I get from decompiling the game in either IDA or x64dbg, I can locate a function I am specifically ...
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The way to determine how the decompiled constructor is structured
I have the following constructor decompiled by Ghidra, i.e. Game. I know some of the functions, which are part of that constructor. And thus I have created my interpretation of that structure. But I ...
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Branching in arm assembly
This is an example assembly code:
function0()
0x0.mov r0, #1
0x8.mov r1, #20
0x10.mov r2, #6
0x18.cmp r1, #16
0x20.b function1
function1()
0x28.cmp r0, #1
0x30.b functionX
functionX(...
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Function Arguments/Name on Radare and IDA
I am starting with reverse engineering and Radare and I'm facing the following problem, on IDA Free I see the following code:
mov ecx, 11h
lea edi, [esp+1208h+StartupInfo]
rep stosd
lea ...
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does mov DWORD PTR 32[rsp], 5 means mov DWORD PTR [rsp+32], 5?
I am learning about windows x64 calling convention, where the first four arguments are passed to registers and left arguments are passed through the stack. To see it, I checked the assembly of the ...
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finding a not-so-straightforward game's function
I am working on Mad Max game [ APEX engine ]
I do my best to explain the situation.
so my target executes function like this:
there are commands like " call [eax+XX] " or " call RX &...
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1
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967
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main function not found in GCC compiled code
I'm trying to learn reverse engineering using Radare2.
For this I compiled a hello world program with GCC on Ubuntu (version: gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0).
#include <stdio.h>
int ...
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Is it possible to make a dynamic memory allocated .data segment to static in a file?
Sorry if this is a dumb question I'm new to assembly.
Basically I want to modify a function in a .exe file to return with a different data, but my issue is that the memory location of the data segment ...
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2
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Cannot disassemble exported functions
I want to disassemble a function from Kernel32.dll to see what it does, but every single function I try looks like this in the decompiler:
Function:
jmp ds:Function_0
Where is the function? ...
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Reverse engineering mode X VGA function(s)
I'm trying to reverse engineer an old DOS game. At the moment I'm stuck at a function that implements some functionality of VGA running in mode X. My issue is that any of the available sample codes on ...
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Converting rep movsd to to C without memcpy
So I am currently in the stages of creating binexact version of functions in decompiled code. I noticed that in this function the rep movsd is called and logically this is translated as Qmemcpy/memcpy ...
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249
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Why some functions in IDA can't be searched
I don't know why but I noticed, on some program I am reversing, that in a section named .bss, there functions and I can't find them through the regular search, why is that.
For example, I wanted to ...
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How to view the functions of a loaded library in x64dbg
I am working on a packed file with UPX.
In one of the lines it calls to the value of the address 0xF5222C which is: 0x778057c0.
The debugger auto-completes it to kernel32.LoadLibraryA.
Where can I ...
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How to track output parameters in disassembly?
I have the following disassembly of winload!CmpFindNlsData function and I need to check the output parameters of this function.
P.S.: CmpFindNLSData(int a1<eax>, int a2, PUNICODE_STRING ...
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1k
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Having hard time analyzing stripped code
This is my first time doing RE on a statically linked and stripped binary with ghidra. And I'm having a really hard time analyzing what function does what just by looking the decompiled code present ...
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Removing/bypassing a BIOS whitelist
I am trying to bypass or erase the BIOS whitelist on my Thinkpad T440p. So far I've
used flashrom and a soic8 clip to dump the bios to a bios.img file
made another dump and compared with diff bios....
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Reversing Pyarmor Discussion
Anyone messing around with pyarmor recently? For those of you that are unaware of what pyarmor is, its a protection software that is to help obfuscate and protect your software. Heres an image of what ...
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Ghidra error when edit main signature function
I'm new to ghidra.
I download the easy_reverse from crackme.one and open the executable file in ghidra.
When I'm trying to edit the main function signature I get an error: Can't parse name: argv[].
I ...
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text_mn in Radare2 --> Meaning?
I compiled some source code and extracted functions with Radare2 (afj).
Often I get a function with "sym..text_mn" function name/ symbol.
The other functions are named correctly. What does this ...
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Understanding obscure function names [duplicate]
I have seen functions like this before in disassembly but don't have a clue what they are. Their names are extremely confusing. Would someone be able to explain what these are?
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Extracting functions of .obj file (compiled by myself with Visual Studio 19) --> extracts wrong data
How can I find only real functions not data garbage like section..debug_S_105 ? *
I need to collect function data (assembler code) of Open Source C++ Files which I compile with Visual Studio 19 (sln ...
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How to extract static API sequences of a PE file?
How does one extract the static API sequences of a PE file? I don't mean the imports listed in the imports segment.
I am currently using different RE tools like Ghidra, IDA Pro, and Binary Ninja. ...
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Function's signature with unmatching parameters
I have following code disassembled by ghidra:
PUSH EBX
PUSH dword ptr [EBP + param_1] wchar_t * _Format for swprintf
PUSH u_%s\%s_0040eb88 size_t ...
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Call function by ebp
When I looking at exe file with Ida I see
call dword ptr [ebp -70p]
What is that? Why this function calling by ebp and not call sub_0xabcd
How can I know which function is that to enter to this ...
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1
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4k
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Dump value of register using frida
I'm new with frida and came to this problem.
I have dll that I want to reverse engeneer(there are no debug symbols). Specifically I want to dump some data from a function. So I have this big function ...
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'local call from' in x64dbg
In OllyDbg there was a thing called "local call from xxx,xxx,xxx,xxx ... " which helps me know from where a function is being called in the entire module. Does such a feature exist in x64dbg as well?
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Is it possible to call external functions?
I was wondering, assuming I wrote a dll in C++ and could access another application's memory, is it possible to call outside functions if I had the address?
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Is it possible to build an equivalent function just looking at the input and output of the original function?
Imagine you are reverse engineering a software. This software uses a library, which is obfuscated and encrypted. The library contains a function, lets call it secret_function. This function is a pure ...
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Is there a way to modify number of reads/writes to/from a memory address?
I haven't had any luck researching this, so I thought I would inquire here!
Let's assume I have found a memory address housing a value of interest. Using a program like Cheat Engine, I look for ...
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How to see all functions that called with debugger
I debugging with IDA, and I want to see/print all the functions that get called.
In the functions window I see over than 1000 functions.
So I want to see which functions are called when I press ...
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Get interface definition of undocumented COM objects
I have started exploring COM objects, initially I got to it from UAC bypass methods but I guess my question is general. The general question is: How can I get from (elevated) CLSID in the registry to ...
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Batch rename functions knowing their prototypes in IDA Pro
I have a long list of mappings from IDA function names (sub_??????) to known function prototypes. The prototype is complete, I mean it contains the return type, the name as in the code and the ...
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Is it possible to get the formula out of a blackbox using neural network
I have a so. library which I know the "C" interface but I don't have access to the source code only the disassembled code which is hard to understand at least for me.
I know the input parameters (...
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Finding RegisterNatives function calls in JNI_OnLoad's assembly code
My goal is to see what a native method m does. It doesn't have a direct counterpart in the so file, but I've found the JNI_OnLoad function's ARM assembly code. It starts with
AAAAAAAA <JNI_OnLoad@@...
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What is the difference between xrefs and stack trace?
In IDA, I can see what calls a specific function by looking at the xrefs to it, or by looking 1 step back on stack trace.
What are the differences between them?
How does IDA know what the stack ...
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IDA function never called and only cross-referenced as data
When I press the X key (list x-refs) on a function (sub_xyz) to see which functions call it, I only saw dd offset sub_xyz twice, with no call sub_xyz instructions.
There is no another place that ...
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Why do many imported functions jump to addresses that do not contain instructions?
I am learning to analyze binaries using radare2 and have been confused about what occurs within imported functions. In the binary below, titled Lab2B, I statically disassembled the binary and then ...
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Tracing function calls in x64dbg
I'm new with x64dbg and want to know if there is any way to get the trace of a functions inside a module?
I've used trace over option, but basically it just traces all the insturctions but doesn't "...
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2
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IDA: call a function with different arguments
I'm reversing some software and found the function which decrypts some stuff:
As you can see it has the password parameter for it which gets decrypted in this function.
Function disassembly:
...
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