shc
Section: User Commands (1)
Updated: Aug 25, 2015
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- OPTIONS
-
- ENVIRONMENT VARIABLES
-
- EXAMPLES
-
- BUGS
-
- AUTHOR1
-
- AUTHOR2
-
- REPORT BUGS TO
-
NAME
shc - Generic shell script compiler
SYNOPSIS
shc
[ -e date ]
[ -m addr ]
[ -i iopt ]
[ -x cmnd ]
[ -l lopt ]
[ -o outfile ]
[ -ABCDhUv ]
-f script
DESCRIPTION
shc
creates a stripped binary executable version of the script
specified with -f on the command line.
The binary version will get a .x extension appended by default if
outfile is not defined with [-o outfile] option
and will usually be a bit larger in size than the original ascii code.
Generated C source code is saved in a file with the extension .x.c
or in a file specified with appropriate option
If you supply an expiration date with the -e option the
compiled binary will refuse to run after the date specified.
The message "Please contact your provider" will be displayed instead.
This message can be changed with the -m option.
You can compile any kind of shell script, but you need to supply valid
-i, -x and -l options.
The compiled binary will still be dependent on the shell specified
in the first line of the shell code (i.e. #!/bin/sh), thus shc does not create
completely independent binaries.
shc itself is not a compiler such as cc, it rather encodes and
encrypts a shell script and generates C source code with the added expiration
capability. It then uses the system compiler to compile a stripped binary
which behaves exactly like the original script. Upon execution, the compiled binary
will decrypt and execute the code with the shell -c option.
Unfortunatelly, it will not give you any speed improvement as a real C program would.
shc's main purpose is to protect your shell scripts from modification or
inspection. You can use it if you wish to distribute your scripts but don't
want them to be easily readable by other people.
OPTIONS
The command line options are:
- -e date
-
Expiration date in dd/mm/yyyy format [none]
- -m message
-
message to display upon expiration ["Please contact your provider"]
- -f script_name
-
File name of the script to compile
- -i inline_option
-
Inline option for the shell interpreter i.e: -e
- -x comand
-
eXec command, as a printf format i.e: exec(\\'%s\\',@ARGV);
- -l last_option
-
Last shell option i.e: --
- -o filename
-
output to the file specified by filename
- -r
-
Relax security. Make a redistributable binary which executes on
different systems running the same operating system. You can release
your binary with this option for others to use
- -v
-
Verbose compilation
- -D
-
Switch on debug exec calls
- -U
-
Make binary to be untraceable (using strace, ptrace, truss, etc.)
- -C
-
Display license and exit
- -A
-
Display abstract and exit
- -B
-
Compile for BusyBox
- -h
-
Display help and exit
ENVIRONMENT VARIABLES
- CC
-
C compiler command [cc]
- CFLAGS
-
C compiler flags [none]
EXAMPLES
Compile a script which can be run on other systems with the trace
option enabled (without -U flag):
shc -f myscript -o mybinary
BUGS
The maximum size of the script that could be executed once compiled is limited
by the operating system configuration parameter
_SC_ARG_MAX
(see
sysconf(2))
AUTHOR1
Francisco Rosales
<frosal@fi.upm.es>
AUTHOR2
Jahidul Hamid
<http://github.com/neurobin>
REPORT BUGS TO
<http://github.com/neurobin/shc/issues>
Time: 06:09:34 GMT, August 25, 2015