Setuid not working in Linux as script fails to write to file. Post: 302827429

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Top Forums Shell Programming and Scripting Setuid not working in Linux as script fails to write to file. Post 302827429 by Just Ice on Friday 28th of June 2013 04:26:38 PM

06-28-2013

Registered User

another option is to port the script into c program binary ... chmod 711 binary and place it in a protected directory ... users can then run the program at will without being able to read anything as long as they have the correct path ... encrypt all source code in a protected directory ... sample below runs hostname in shtest ... lstest is just a copty of /bin/ls ...

if taking this option, make sure you account for what the users may want to change (i.e., different file path, current time, logfile name, etc.) so there is no constant recompile and looking at the sourcecode ...

from regular user perspective:

Code:

otto@susegeek:/tmp> cd testdir
otto@susegeek:/tmp/testdir> ls -ld
drwxr-xr-x 3 root root 4096 Jun 28 15:48 .
otto@susegeek:/tmp/testdir> ls -l
total 4
drwx--x--x 2 root root 4096 Jun 28 15:39 700
-rw-r--r-- 1 root root    0 Jun 28 15:48 test1
-rw-r--r-- 1 root root    0 Jun 28 15:48 test2
-rw-r--r-- 1 root root    0 Jun 28 15:48 test3
-rw-r--r-- 1 root root    0 Jun 28 15:48 test4
-rw-r--r-- 1 root root    0 Jun 28 15:48 test5
otto@susegeek:/tmp/testdir> ls -l 700
ls: cannot open directory 700: Permission denied
otto@susegeek:/tmp/testdir> ls -l 700/shtest
-rwx--x--x 1 root root 33 Jun 28 15:21 700/shtest
otto@susegeek:/tmp/testdir> ls -l 700/lstest
-rwx--x--x 1 root root 112892 Feb 18  2011 700/lstest
otto@susegeek:/tmp/testdir> 700/shtest
/bin/ksh: 700/shtest: cannot open [Permission denied]
otto@susegeek:/tmp/testdir> 700/lstest
700  test1  test2  test3  test4  test5
otto@susegeek:/tmp/testdir> strings 700/lstest
strings: 700/lstest: Permission denied
otto@susegeek:/tmp/testdir> cat 700/shtest
cat: 700/shtest: Permission denied
otto@susegeek:/tmp/testdir>

from root's perpective:

Code:

susegeek:/tmp/testdir # ls -ld .
drwxr-xr-x 3 root root 4096 Jun 28 15:48 .
susegeek:/tmp/testdir # ls -ld *
drwx--x--x 2 root root 4096 Jun 28 15:39 700
-rw-r--r-- 1 root root    0 Jun 28 15:48 test1
-rw-r--r-- 1 root root    0 Jun 28 15:48 test2
-rw-r--r-- 1 root root    0 Jun 28 15:48 test3
-rw-r--r-- 1 root root    0 Jun 28 15:48 test4
-rw-r--r-- 1 root root    0 Jun 28 15:48 test5
susegeek:/tmp/testdir # ls -l 700
total 116
-rwx--x--x 1 root root 112892 Feb 18  2011 lstest
-rwx--x--x 1 root root     33 Jun 28 15:21 shtest
susegeek:/tmp/testdir # file 700/*
700/lstest: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.4, stripped
700/shtest: Korn shell script text
susegeek:/tmp/testdir # 700/shtest
susegeek
susegeek:/tmp/testdir # 700/lstest
700  test1  test2  test3  test4  test5
susegeek:/tmp/testdir #

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hp9000s300

machid(1)						      General Commands Manual							 machid(1)

NAME

       machid: hp9000s200, hp9000s300, hp9000s400, hp9000s500, hp9000s700, hp9000s800, hp-mc680x0, hp-pa, pdp11, u370, u3b, u3b10, u3b2, u3b5, vax
       - provide truth value about processor type

SYNOPSIS

DESCRIPTION

       The following commands return a true value (exit code 0) if the a processor type matches the command name.  Otherwise a false  value  (exit
       code  nonzero)  is returned.  These commands are commonly used within makefiles and shell procedures to improve portability of applications
       (see make(1)).

				       +-----------+-------------------------++--------+--------------------------+
				       |Command    | True for		     ||Command | True for		  |
				       +-----------+-------------------------++--------+--------------------------+
				       |hp9000s200 | Series 200 	     ||pdp11   | PDP-11/45 or PDP-11/70   |
				       |hp9000s300 | Series 300 	     ||u3b     | 3B20 computer		  |
				       |hp9000s400 | Series 400 	     ||u3b2    | 3B2 computer		  |
				       |hp9000s500 | Series 500 	     ||u3b5    | 3B5 computer		  |
				       |hp9000s700 | Series 700 	     ||u3b10   | 3B10 computer		  |
				       |hp9000s800 | Series 800 or 700	     ||u370    | IBM System/370 computer  |
				       |hp-mc680x0 | Series 200, 300, or 400 ||vax     | VAX-11/750 or VAX-11/780 |
				       |hp-pa	   | Series 700 or 800	     ||        |			  |
				       +-----------+-------------------------++--------+--------------------------+
EXAMPLES

       Given a shell script that must behave differently when run on an HP 9000 Series 700 or 800 system, select the correct code  segment  to	be
       executed:

WARNINGS

       always  returns	true on both Series 800 and Series 700 systems.  Therefore, when using this command in scripts to determine hardware type,
       always use both and in the appropriate sequence to ensure correct results (see

       machid(1) will no longer provide support for future machines beyond the Series 800 and Series 700 systems.  Decisions should  be  based	on
       the hardware and software configuration information returned by getconf(1).

SEE ALSO

       getconf(1), make(1), sh(1), test(1), true(1).

																	 machid(1)