shc

shc is a command-line tool used for shell script compilation. It stands for "Shell Compiler," and its primary function is to take a shell script written in bash or a compatible language and convert it into a binary executable. The resulting binary can be executed directly without the need for an interpreter.

One of the main purposes of shc is to protect sensitive information present in shell scripts by obscuring the source code. The compiled binary is much harder to reverse engineer compared to the original script.

shc achieves this by using a combination of encryption and code obfuscation techniques. It encrypts the original script and merges it with a self-extracting C code. This makes it difficult for attackers to extract the original shell script from the binary.

The tool also provides additional options like setting an expiration date for the compiled binary, so that it becomes unusable after a certain period. It can also bind specific system libraries into the binary, ensuring compatibility across different systems.

Users can specify additional compile-time options to customize the behavior of the compiled binary, such as defining macros or disabling certain features.

While shc adds a layer of protection to shell scripts, it is important to note that it is not foolproof and determined attackers may still be able to reverse engineer the binary to some extent.

shc is primarily available for Unix-like operating systems and is widely used in scenarios where shell script source code protection and distribution of self-contained binaries are required.