[SOLVED] Find SU binary source

Issue

Where can I find the source code for the SU binary in linux? The entire OS is open source, so why can't I find it? I can find the SUDO source, but that's not what I'm looking for.

Solution

Debian Stable:

$ which su
/bin/su

$ apt-file search /bin/su | grep "/bin/su$"
login: /bin/su

$ apt-cache show login | grep "Homepage"
Homepage: http://pkg-shadow.alioth.debian.org/

<open page, click Download, observe github link>
https://github.com/shadow-maint/shadow

https://github.com/shadow-maint/shadow/blob/master/src/su.c

Answered By - genpfault

Answer Checked By - Marie Seifert (WPSolving Admin)