Questions tagged [hexrays]
A decompiler plugin for IDA, producing (pseudo-)C/C++ code, developed by the company of the same name (Hex-Rays).
112
questions
2
votes
0answers
67 views
Understanding Hex-Rays syntax
I have a Ida decompiled function that invokes another function through a function pointer but I'm really confused how it calculates it's address. I'm new to hex-rays syntax.
int __fastcall SUB_XXXX(...
0
votes
1answer
62 views
An incomprehensible line in the output from hex rays
v5 = (*(int (__cdecl **)(int))((char *)&etext + 1))(a1);
Please explain me what does this line mean (if possible, please write from what it was compiled from (language - c))
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votes
0answers
46 views
Is there a way to aid the IDA decompiling process?
I want to make all local variables contained in a structure with appropriate padding put in the gaps (unused parts of the frame). I want to do the same for the global data. And I want to rename ...
0
votes
0answers
67 views
Control flow graph of entire binary file
Is it possible to get the control flow graph of the entire binary file using any disassembler? IDA Pro generates the CFG for each function. Can we use it to get the CFG of the entire program?
3
votes
1answer
95 views
Specifying the register value which is constant for all the functions
In the firmwares I met the situation when some register value is set at startup, and then it's implicitly used as a base address to access the variables.
e.g. register r13 is set to 0x40000000 which ...
1
vote
1answer
76 views
How to stop Hex Rays optimizations?
I know it's not a bug, but a feature. Hex Rays found that there's a variable which is set to specific value, thus there's no need to display the branches where the code will never be run, so it warns ...
1
vote
1answer
57 views
IDA HexRays: signed/unsigned types and 32/64 bits dont match assembly
Here is assembly:
mov rdi, [r13+rax*8+0]
sub rdi, rcx
cvtsi2sd xmm0, rdi
movsd qword ptr [r11+rax*8], xmm0
cvtsi2sd xmm0, qword ptr [r14+rax*8]
movsd qword ptr [rsi+rax*8], ...
1
vote
2answers
953 views
Hex-Rays not properly showing strings
Here's the difference between Hex_Rays and the debugger:
Note that I've synchronized the views, so they are showing the same operations in both the debugger and the decompiler. I've tried Edit -> ...
0
votes
1answer
53 views
What does this custom piece of frame manipulation code from a router binary do?
I've decompiled a custom router ELF binary using Hex-Rays and have recently come across the following function in the binary:
pkt_hdr_t *__cdecl pkt_hdr_from_frame(frame_t *frame, uint16_t *remaining)
...
0
votes
1answer
36 views
LPC2378FBD144 Arm7 hex file
I have binary file for the LPC2378FBD144 processor ineed to reverse engineer it using IDA V7.3
im little confused about memory organization values i should put in the memory organization thank you for ...
0
votes
1answer
236 views
Analyzing raw binary without ELF header in IDA Pro
I am trying to analyze and disassemble a raw binary that does not have an ELF header using IDA Pro.
I have been trying to convert to code using MakeCode, but have not gotten anywhere as the binary is ...
4
votes
2answers
283 views
How to show KUSER_SHARED_DATA members in decompiled C code?
Here is a sample C code which prints Windows version directly from address
of KUSER_SHARED_DATA. Tested in Windows 10 only. The raw memory address
differ in Windows version but that's not the point.
#...
0
votes
0answers
168 views
idapython: how to apply hexrays types to disassembly interface
I am using idapro 7.5 to get variable information from binaries.
Consider following simple code:
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char *argv[])
{
int i, N, ...
1
vote
1answer
199 views
IDA/HexRays: how do I retrieve the memory address associated with a given line of decompiled code?
I'm trying to programmatically link decompiled code generated by HexRays with the disassembly code of a given binary by mapping memory addresses between the two. The mapping exists, as I can see view ...
1
vote
2answers
203 views
STL Data Structures Hex-Rays
We all know that reversing STL code is no fun. To make it easier, I usually create some of the strucutres so I can reference the created STL structures in another custom structure.
For example, msvc - ...
-1
votes
1answer
72 views
What does xchg means when accessing array element?
I have ASM code of some Windows *.exe in IDA:
mov rax, [rbx+10h]
mov ecx, edx
xor edx, edx
xchg rdx, [rax+rcx*8]
Which is decompiled to pseudocode to
_RAX = this->m_someMemoryPool;
...
1
vote
2answers
613 views
Batch decompile using IDA Pro 7.5
I am trying to batch disassemble and decompile 500 binaries using the IDA Pro 7.5 disassember and Hex rays decompiler. I can get the .i64 output from the disassembler, but I do not have a way to batch ...
0
votes
2answers
259 views
asm snippet to pseudo-code
I'm looking into a way to generate pseudo-code from snippet of assembly,
let's assume I have this ASM
push rbp
mov rbp, rsp
mov DWORD PTR [rbp-4], edi
mov DWORD PTR [...
0
votes
1answer
272 views
How to reverse engineer Apple MacBook SMC update firmware image using IDA Pro 7.2?
Alright so I have watched extraordinary presentations videos from three different reverse engineers who hacked the Apple SMC Update firmware:
Charlie Miller:
https://www.youtube.com/watch?v=...
1
vote
1answer
63 views
Hex Rays Mapping To Wrong Variable
The assembly file has multiple variables which both use the rax register. The decompiler did recognize that at least somewhat, since it did create two variables which use the rax register. However, it ...
1
vote
1answer
367 views
IDA/Hexrays: local variable allocation has failed; how to fix this?
I'm reverse engineering an old DOS game that's using the DOS/4GW extender. The game includes some libraries that I already successfully reversed in a different application, so I'm pretty sure that the ...
0
votes
1answer
135 views
Re-analyzing pseudocode IDA Pro
While I was reversing a binary I noticed that IDA Pro had adjusted the pseudocode that initially was generated. This happened after I started reversing the binary and renamed functions and variables ...
3
votes
0answers
425 views
IDA Hex-Rays structure inline functions recognition
I've seen multiple posts about the subject, but mine is a little bit more specific about what I want to achieve.
I have many times situations where Hex-Rays decompiler outputs 16 lines of code and I ...
1
vote
1answer
125 views
Hex-Ray Decompiler: inline function not recognized
While trying to decompile an application with Hex-Ray 7.0, I stumbled upon the problem that in nearly all cases, what seems to be a certain inline function will not be recognised, which bloats the ...
1
vote
2answers
450 views
Methods for preventing IDA decompiler
I want to write a C function, such that hex-rays decompiler will fail on it. I want to do it for study purposes, and not for an actual anti-reversing method. Do you have any recommendations/approaches ...
2
votes
1answer
209 views
IDA pseudocode support
How can I know which processors IDA knows how to view pseudocode of?
If IDA does not know to view pseudocode for my processor, how can I fix that??
0
votes
2answers
445 views
Hex-Rays skips code
have using IDA Pro 6.8 (Hex-Rays 2.2), default settings.
Problem starts happens when i trying to analyze function (which actual size ~2886 bytes), pressing F5 (without errors or alerts) and getting ...
2
votes
2answers
1k views
How to help IDA to auto complete libc functions?
I have a x86_64 ELF binary which is statically compiled. With some digging,
I have found the C library is musl. In IDA Pro 7.0, the decompiled pseudo code
shows sycalls as inline assembly code. But in ...
1
vote
1answer
288 views
Is there a way to show exceptions handlers in Hex-Rays decompiler output?
Is there a way to show these exception handlers in the decompiled code?
I can't tell that a block is in a __try block without looking into the disassembly.
__int64 __fastcall ...
2
votes
1answer
143 views
How to migrate IDA/HexRays database to the new version of the same application?
I have an .idb and PE file of an old version of an application. Now I want to transfer all knowledge to a new database for the new version of PE. How can I do this?
It seems that I need to compare ...
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vote
0answers
91 views
How Can I Clean Up After IDA Decompation with IDAPython or other resource
When I am working on a source code recovery project I am usually left with a lot of code that needs to be manually cleaned up by hand. This can take a lot of time and as projects get larger , I am ...
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votes
1answer
155 views
Understanding (pseudo-)C function from a video game [closed]
I recently found a function using IDA within a game that creates a CRC from a string. I don't understand much of the code or how the game takes in the string as data.
__int64 __fastcall ITF::...
1
vote
1answer
2k views
Decompile large function in IDA
I'm working on a crack me, specifically: jaunsacco's DragonCrack and the first thing I've gotten stuck on is that the program is built mostly as a enormous main function. After attempting to decompile ...
1
vote
1answer
212 views
Weird IDA/Decompiler floating point output
I stumbled upon this (reduced for readability) function. It does weird things that I have never encountered before.
// a2 is always 60.0
void some_function(struct_123 *this, float a1, float a2)
{
...
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vote
0answers
177 views
IDA Pro Reset All Stack Pointers to Default
Is there a way letting IDA scan all the database and reset all stack pointers values to it's default state that were previously modified? i.e like it was when I first started the analyzing the binary?
...
2
votes
0answers
203 views
IDA Hex-Rays Decompiler Generates ASM Code Issue
For a long time now, I've been struggling with some functions generated with IDA HexRays plugin that seem to be corrupted.
Some of the decompiled generated plain C code, show as ASM code :/
i.e:
...
0
votes
1answer
1k views
How can I follow virtual function calls in IDA?
I'm trying to reverse a video game that was made with the CryEngine 5 game engine. CryEngine 5 source code is available on GitHub, so I can look at the CryEngine source code and cross reference with ...
0
votes
1answer
113 views
Why Ida pseudo-code translate test as AND?
In IDA when disassembling a x86 EXE file there is a line
test byte ptr [ebp+XXX], cl
Before this line cl has a value of 0x11
The Hex-Rays decompiler plugin translates it as if (v10 &0x11).
Why ...
1
vote
2answers
1k views
IDA Hex-Rays: How to SAFELY fix incorrect function declarations?
Update:
The problem turned out to be more complex and complex because Hex-Rays incorrectly restores the stack after calls of stdcall functions from cdecl functions:
.text:00403F2F 074 ...
0
votes
2answers
2k views
IDA Hex-Rays: How to find all references to the certain field of all instances of the data type?
This question has already been asked here but for some reason it was deleted, as "dead".
I will try to explain again. I have a specific data type. It is used in a large number of disassembled ...
0
votes
3answers
1k views
Understanding Hex-Rays pseudo code
What is the meaning of the following pseudo-code?:
BYTE1(v2) or BYTE1(v2)
HIBYTE(v2)
Is there any explanation for those macros? How can I implement those macros in C code?
2
votes
2answers
505 views
Nested Structures in IDA
I'm trying to figure out how to explore structs in IDA, and getting stuck on the basics. I wrote a very basic test app;
int main() {
const int kBits = 1024;
const int kExp = 3;
RSA *rsa =...
1
vote
2answers
342 views
How to remove all goto statements in pseudocode?
IDA shows multiple goto statements in the decompiled pseudocode. I've read this manual page: https://www.hex-rays.com/products/decompiler/manual/config.shtml and tried to disable/enable these flags ...
1
vote
0answers
460 views
IDA 7 handling strings in debugger pseudocode
When running a remote debugger to a linux server, is there a way to get IDA (7.0) to properly handle strings? When I go to the pseudocode view, I get things like this;
v7 = sub_804AD60((std::string *)...
1
vote
2answers
1k views
.NET assembly IDA PRO, using LDSTR IL op code, how to patch a string?
I'm trying to patch a string. So right now I'm trying to replace instruction LDSTR with LDSTR "mystring"; however, I have been unsuccessful. After assembling the LDSTR op code, I don't quite ...
4
votes
1answer
876 views
Resolving FLAGS bits with IDA
While disassembling a binary, IDA decompiler decompiles the call as mmap(0x80000000, 4096, 7, 50, -1, 0); While there is nothing wrong with the decompilation itself, it could be more useful to decode ...
0
votes
1answer
374 views
Translating ida macros and pseudocode into C++/C
What would be the translated C output of this hexrays decompiler pseudocode? The values of v6 and v5 are floats just as v8. The value of xmmword_108365D0 is 7FFFFFFF7FFFFFFF7FFFFFFF7FFFFFFFh
v8 = (...
1
vote
2answers
3k views
How to add/find parameters to a function declaration in IDA/HexRays?
I've a binary opened in IDA. It uses a function pointer from a COM vtable. I found that the COM method has 13 parameters (including this). But IDA shows only 4 parameters as shown in this pseudocode:
...
3
votes
2answers
4k views
IDA Hex-Rays Decompiler : Show strings instead of offset
How can i settings IDA show me string instead of offset_xxx?
3
votes
1answer
1k views
How do I resolve IDA pro Hexrays aliased local variables?
It appears to me that in my function the compiler has reused a stack slot for two variables of types. However, Hex-Rays has not recognized it as such. How can I split the local variable into two?
