Shellen is an interactive shellcoding environment. If you want a handy tool to write shellcodes, then shellen may be your friend. Also, it can be used just as assembly/disassembly tool.
Shellen works only on python3. Maybe it will be changed in the future.
You can install the stable version of shellen using pip3:
Or if you already have all required packages (see Requirements):
$ sudo pip3 install shellen
If you have any trouble with installing keystone-engine, then you should compile it by yourself (see the COMPILE.md file in the keystone repository)
$ python3 setup.py install
How to run:
After installing shellen and all its required packages, you can run shellen just by typing the next in your terminal:
There is the
helpcommand inside the tool, that will explain almost everything.
Shellen was created for assembling and disassembling instructions, so there are two modes of using the tool: asm and dsm respectively. Of course, there are some other possibilities like syscalls tables, common shellcodes and other.
If you find a problem/bug or something, then just write an issue about this problem. Also, if you think, that some feature will be nice to use in shellen, then do the same -- write an issue and I will try to add this feature.
It also has a usefull prompt, displaying current mode, OS (Operating System for syscalls) and chosen architecture exactly for this mode. It looks as follows:
You can edit your input like you're typing in a terminal. Also, it has a history of commands (just type up arrow to see them).
Lis the shortened name of
Linuxin the prompt. Below listed all other OS names:
setos [linux/windows/macos]as follows:
To change current mode, enter
L:asm:x86_32 > setos windows
[+] OS changed to windows.
dsmin the prompt.
L:dsm:arm32 > asm
[+] Changed to asm (assembly) mode
L:asm:x86_32 > dsm
[+] Changed to dsm (disassembly) mode
To assembly instuctions, type them separated by colons as follows:
If your assembled bytes contain a null byte, then shellen will tell you about this.
L:asm:x86_32 > mov edx, eax; xor eax, eax; inc edx; int 80;
[+] Bytes count: 7
Raw bytes: "\x89\xc2\x31\xc0\x42\xcd\x50"
Hex string: "89c231c042cd50"
It works exactly as assembling. Type your bytes in the input prompt and see the result!
L:dsm:x86_32 > 89c231c042cd50
0x00080000: mov edx, eax
0x00080002: xor eax, eax
0x00080004: inc edx
0x00080005: int 0x50
dsmmodes work for different architectures. To see a list of available architectures for a current mode, type this:
And if you want to change current architecture, enter follow:
L:dsm:x86_32 > archs
│ │ │ │ │ │
│ arm32 │ mips32 │ sparc32 │ systemz │ x86_16 │
│ arm64 │ mips64 │ sparc64 │ │ x86_32 │
│ arm_tb │ │ │ │ x86_64 │
L:dsm:x86_32 > setarch arm32
[+] Architecture of dsm changed to arm32
It's apparent that in process of crafting a shellcode you will be needed syscalls. So, shellen will help you with that. Just type
syswith a name of desired syscall and shellen will show you a list of possible syscalls you were looking for.
This prints possible variants of syscall depending on entered pattern. Syscall table for searching depends on chosen architecture and OS (Operating System). In this case it's
L:asm:x86_32 > sys open
│ name │ eax │ ebx │ ecx │ edx │ esi │
│ open │ 0x05 │ const char *filename │ int flags │ umode_t mode │ - │
│ openat │ 0x127 │ int dfd │ const char *filename │ int flags │ umode_t mode │
Shellen can show you a list of common shellcodes depending on your keyword. The example of using placed in
Picturessection. It uses API of shell-storm.org site (thanks to the author!). You can use it like this:
L:asm:x86_32 > shell <keyword> <count>
countparameter isn't required.
It was assumed that there will be several OSs (Linux, Windows and MacOS), but right now supported only Linux. If you want to add functionality for Windows or MacOS, then write an issue and I will add it.
| ||Clear the terminal screen. As usual |
| ||Show the help message.|
| ||Finish the current session and quit|
Just a little bunch of pictures.