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UID_WRAPPER(1)   UID_WRAPPER(1)

NAME

uid_wrapper - A wrapper to fake privilege separation

SYNOPSIS

LD_PRELOAD=libuid_wrapper.so UID_WRAPPER=1 UID_WRAPPER_ROOT=1 ./myapplication

DESCRIPTION

•Allows uid switching as a normal user.
•Start any application making it believe it is running as root.
•Support for user/group changing in the local thread using the syscalls (like glibc).
•More precisely this library intercepts seteuid and related calls, and simulates them in a manner similar to the nss_wrapper and socket_wrapper libraries.
Some projects like a file server need privilege separation to be able to switch to the connection user and do file operations. uid_wrapper convincingly lies to the application letting it believe it is operating as root and even switching between UIDs and GIDs as needed.

ENVIRONMENT VARIABLES

UID_WRAPPER
If you load the uid_wrapper and enable it with setting UID_WRAPPER=1 all setuid and setgid will work, even as a normal user.
UID_WRAPPER_ROOT
It is possible to start your application as fake root with setting UID_WRAPPER_ROOT=1.
UID_WRAPPER_DEBUGLEVEL
If you need to see what is going on in uid_wrapper itself or try to find a bug, you can enable logging support in uid_wrapper if you built it with debug symbols.
•0 = ERROR
•1 = WARNING
•2 = DEBUG
•3 = TRACE

EXAMPLE

$ LD_PRELOAD=libuid_wrapper.so UID_WRAPPER=1 UID_WRAPPER_ROOT=1 id
uid=0(root) gid=0(root) groups=100(users),0(root)
07/11/2014