04-08-2007
10 More Discussions You Might Find Interesting
1. Cybersecurity
Hi all
what are the ways by which we can know and generate a report of the space remaining, memory(ram) used and the load on the server over a period of time. (1 Reply)
Discussion started by: arlan
1 Replies
2. UNIX for Dummies Questions & Answers
Hi everybody,
Can anyone suggest me some good books on Linux Prog.. I know richard stevens is always there.. But any specific books on Linux Porgramming and Networking in Linux.. Wud be of great help if anybody replies.. (4 Replies)
Discussion started by: srikumar_cs
4 Replies
3. Programming
Dear Friends,
How we can call the Linux commands like ls, cat, grep, clear and others Linux commands in C programs. (6 Replies)
Discussion started by: krishna_sicsr
6 Replies
4. UNIX for Advanced & Expert Users
I would like to call a particular function in a C program using execl(). Is this possible using execl or anyother function ?
Thanks (2 Replies)
Discussion started by: vpraveen84
2 Replies
5. Linux
hi , i have 2 linux boxes with linksys wireless adapters everything is working fine.now i am trying to run client-server program written in C on these boxes but none of the box is receiving any packets. how different it is when using wireless . All these codes that i have works fine on Unix though... (1 Reply)
Discussion started by: phantom308
1 Replies
6. UNIX for Advanced & Expert Users
Greetings,
Please help me with the following :
Where can I find what means exactly and how to use each of the second
argument of the ioctl() system call in Linux/386 : FIOxxx (file IOCTL
requests), SIOxxx (socket IOCTL requests), TCxxx TIOxxx (terminal
IOCTL requests) ?
... (1 Reply)
Discussion started by: aigoia
1 Replies
7. Shell Programming and Scripting
I have a java program to validate a XML file. I want to call this java program in a shell script which will be registered as concurrent program in oracle apps.
Can anyone please let me know the step by step appraoch required to call java program in shell script like ....intial steps... (1 Reply)
Discussion started by: kcp_pavan
1 Replies
8. Linux
I encountered a variety of difficulties when implementing a system call as simple as HelloWorld example in Linux so far.
Firstly, according to the book "Linux Kernel Development Second Edition", I tried to implement a syscall in 2.6.31 but no way absolutely because 2.6.10 has a very different way... (5 Replies)
Discussion started by: sunnyhay
5 Replies
9. Shell Programming and Scripting
Hi, I'm writing a shell script where I want to call fork(). However I wrote like this "var=fork()" in c style and got this error:
"syntax error near unexpected token `(' "
How could I call fork() in shell script? Thanks in advance.
Duplicate Post - Continue Here - Please Do Not Cross Post... (0 Replies)
Discussion started by: Xiaoya
0 Replies
10. Shell Programming and Scripting
Hi,
I'm facing issues while trying to run a sample program on Linux.
If I try to run the script using the command "sh <filename.prog>", it doesn't work. But, if I try to execute it using the command "ksh <filename.prog>", it works fine.
Even ". ./filename.prog" works fine.
Can you... (6 Replies)
Discussion started by: venkatesh17
6 Replies
LEARN ABOUT FREEBSD
smrsh
SMRSH(8) System Manager's Manual SMRSH(8)
NAME
smrsh - restricted shell for sendmail
SYNOPSIS
smrsh -c command
DESCRIPTION
The smrsh program is intended as a replacement for sh for use in the ``prog'' mailer in sendmail(8) configuration files. It sharply limits
the commands that can be run using the ``|program'' syntax of sendmail in order to improve the over all security of your system. Briefly,
even if a ``bad guy'' can get sendmail to run a program without going through an alias or forward file, smrsh limits the set of programs
that he or she can execute.
Briefly, smrsh limits programs to be in a single directory, by default /usr/libexec/sm.bin, allowing the system administrator to choose the
set of acceptable commands, and to the shell builtin commands ``exec'', ``exit'', and ``echo''. It also rejects any commands with the
characters ``', `<', `>', `;', `$', `(', `)', `
' (carriage return), or `
' (newline) on the command line to prevent ``end run'' attacks.
It allows ``||'' and ``&&'' to enable commands like: ``"|exec /usr/local/bin/filter || exit 75"''
Initial pathnames on programs are stripped, so forwarding to ``/usr/bin/vacation'', ``/home/server/mydir/bin/vacation'', and ``vacation''
all actually forward to ``/usr/libexec/sm.bin/vacation''.
System administrators should be conservative about populating the sm.bin directory. For example, a reasonable additions is vacation(1),
and the like. No matter how brow-beaten you may be, never include any shell or shell-like program (such as perl(1)) in the sm.bin direc-
tory. Note that this does not restrict the use of shell or perl scripts in the sm.bin directory (using the ``#!'' syntax); it simply dis-
allows execution of arbitrary programs. Also, including mail filtering programs such as procmail(1) is a very bad idea. procmail(1)
allows users to run arbitrary programs in their procmailrc(5).
COMPILATION
Compilation should be trivial on most systems. You may need to use -DSMRSH_PATH="path" to adjust the default search path (defaults to
``/bin:/usr/bin'') and/or -DSMRSH_CMDDIR="dir" to change the default program directory (defaults to ``/usr/libexec/sm.bin'').
FILES
/usr/adm/sm.bin - default directory for restricted programs on most OSs
/var/adm/sm.bin - directory for restricted programs on HP UX and Solaris
/usr/libexec/sm.bin - directory for restricted programs on FreeBSD (>= 3.3) and DragonFly BSD
SEE ALSO
sendmail(8)
$Date: 2013-11-22 20:52:00 $ SMRSH(8)