shellc

Tool for converting scripts into C code

Install

cc shellc.c -O2 -o shellc

IMPORTANT CLAUSE

shellchas been open source for about a year and has been released about 20 times, but due to technical issues that cannot be solved, no new versions will be released in the future. If the code protection requirements are not high, this tool can be used. If there are high protection requirements, do not use such tools. The encryption method of transmitting the source code to the interpreter through pipeline cannot technically solve the problem of obtaining the source code through strace. For the method of cracking the source code, please refer to decrypt. The purpose of releasing cracking methods is to hope that someone can solve the vulnerabilities in cracking tools, while also informing about the risks of using shellc tools. If the scripting language is bash, please use xbash Tools.

Compile shell scripts and generate executable programs

shellc sh example.sh
cc example.sh.c -O2 -o example

The generated C code is example.sh.c, which is the original file name followed by .c. For programs that require source code protection, it is recommended to use static compilation and the stripcommand to remove symbol tables, and enable the -i or -a options.

The tool for converting scripts to C code can obtain the source code through the following ways：

1. The source code can be seen through the ps -ef command，such as the default option generated by shc.

2. Obtaining source code by forging interpreters, such as changing the script interpreter to echo.

3. For code generated by non static compilation, it can be obtained by dynamically loading and intercepting the read function.

4. kill -SIGSEGV , Obtaining script source code through methods such as memory dump.

5. Obtaining script source code by reading the file descriptor /proc/<pid>/fd/* .

6. Obtaining script source code by reading memory files or strace.

Version 1.8 has resolved issues 1-3, but technically cannot solve issue 4-6. If the scripting language is bash, xbashcan solve issue 4-6.

Version 1.0 or above not only support shell, but also other scripting languages, which can completely replace shc. Version 1.6 adds the function of obtaining script source code through anti-counterfeiting interpreter or memory dump. Version 1.8 solves the problem of obtaining source code through file descriptors. Version 1.8 does not support ruby, and ruby requires version 1.7.

At present, the program has practical applications in AIX, UNIX, Linux environments. It is recommended to conduct comprehensive testing on the compiled program to prevent production failures.

User manual

• Generate C code command

  shellc command inputfile [-t] [-a] [-x] [-f fix-format] [-e fix-file] [-p parameter] [-i interpreter] [-b 8|16|32|64] [-d YYYYMMDD] [-m message]

  command： Execute script commands, such sh,perl,python,node,Rscript,php, etc.

  inputfile： Script file name

  -t option： For systems that do not support anti debugging functionality, this option is required for generated code.

  -a option: Anti forgery interpreter requires the MD5 value of the interpreter in the runtime environment to be the same as that of the interpreter in the compilation environment.

  -x option： New version xbash It has become a pure code conversion tool, and -x is no longer valid.

  -f option： Fix parameter 0 value.

  -e option： Fix parameter 0 value by custom external file.

  -p option： Command parameter, such as busybox shell using by shellc busybox example.sh -p sh.

  -b option： Operating system bits setting.

  -i option: Built in interpreter, interpreter is the file name corresponding to the runtime environment, such as /usr/bin/sh, or a custom file name can be used, such as /tmp/myshell. If there is no corresponding interpreter in the runtime environment, the interpreter file will be automatically generated at runtime. Built in interpreter with anti-counterfeiting function.

  -d option: Program expiration date, formatted as YYYYMMDD

  -m option: Program expiration information prompt.

• Fix arguments

  Fix arguments 0 supports BASH, FISH, ZSH, PERL, PYTHON, JAVASCRIPT, LUA, RUBY.

  In addition to built-in fix format, external file can also be used to fix arguments 0. File format：?Indicates parameter 0 value, line breaks must be explicitly used\n, Double quotes require an escape character \.Reference test/fix.txt.

Untraceable

Version 0.3 or above has added untraceable and tested the following tools for untraceable

OS	TOOL	SUPPORTED
AIX 7.1	dbx sdb	YES
SCO UNIX 5.0.6	dbx sdb adb	YES
Red Hat Linux7.8	gdb	YES
CentOS Linux6.4	gdb	YES
debian 12.4.0	gdb	YES
Fedora 39	gdb lldb	YES
FreeBSD 14.0	gdb	YES
openSUSE Leap 15.5	gdb	YES
OracleLinux R9	gdb	YES
ubuntu 22.04.3	gdb lldb	YES
openEuler	gdb	YES
Debian	gdb	YES
NetBSD 10.0	gdb	NO
DragonFly 6.4	gdb	NO
macOS 13	lldb	NO

History

• v1.8.2 2024-11-25

  Fix Issue #27

• v1.8.1 2024-11-11

  Fix memory detection errors in special scenarios

• v1.8 2024-11-10

  Merge normal mode and safe mode

  Add support for xbash

  Prevent debugging by using the ptrace method

  Add program expiration

• v1.7 2024-09-18

  Fix Issue #18

  Safe mode SHELL human-machine interaction support does not modify the source script program

  Add support for safe mode aliases

• v1.6.2 2024-09-01

  Fix memory overflow

• v1.6.1 2024-09-01

  Fix the array length to be empty

• v1.6 2024-09-01

  Add built-in interpreter

  Add anti-counterfeiting interpreter

  Add anti memory dump

• v1.5 2024-08-25

  Fix the incorrect exit status issue in safe mode

• v1.4 2024-08-17

  Fix memory leak

• v1.3 2024-06-28

  Add command parameter

• v1.2 2024-06-22

  Add operating system bits setting

• v1.1 2024-06-12

  Expand functions in safe mode

• v1.02 2024-06-06

  Removing macro definitions from generated code makes it easier for professional tools to generate more complex and confusing code

• v1.01 2024-06-02

  Remove special handling of FreeBSD

• v1.0 2024-06-01

  Add support for non SHELL scripting languages

  Add fix parameter 0

  Remove BSD and LINUX variant system thread requirements

• v0.3 2023-12-25

  Add untraceable

  Fix compilation warnings in some systems

• v0.21 2023-12-13

  Fix program bugs in the zsh environment

• v0.2 2023-12-12

  Changing the data structure from a structured structure to a string array reduces compilation time for large files

  Add code character encryption function

• v0.1 2023-12-01

  Initial version