loncom/lcuseradd - diff

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Diff for /loncom/Attic/lcuseradd between versions 1.18 and 1.41

version 1.18, 2001/11/16 06:18:35	version 1.41, 2007/03/28 20:43:37
Line 5	Line 5
# lcuseradd - LON-CAPA setuid script to coordinate all actions	# lcuseradd - LON-CAPA setuid script to coordinate all actions
# with adding a user with filesystem privileges (e.g. author)	# with adding a user with filesystem privileges (e.g. author)
#	#
# YEAR=2000
# 10/27,10/29,10/30 Scott Harrison
# YEAR=2001
# 10/21,11/13,11/15 Scott Harrison
#	#
# $Id$	# $Id$
###	###
Line 36	Line 32
###############################################################################	###############################################################################

use strict;	use strict;
	use File::Find;


# ------------------------------------------------------- Description of script	# ------------------------------------------------------- Description of script
#	#
# This script is a setuid script that should	# This script is a setuid script that should
# be run by user 'www'. It creates a /home/USERNAME directory	# be run by user 'www'. It creates a /home/USERNAME directory.
# as well as a /home/USERNAME/public_html directory.
# It adds a user to the unix system.	# It adds a user to the unix system.
# Passwords are set with lcpasswd.	# Passwords are set with lcpasswd.
# www becomes a member of this user group.	# www becomes a member of this user group.

# -------------- Invoking script (standard input versus command-line arguments)	# -------------- Invoking script (standard input versus command-line arguments)
	# Otherwise sensitive information will be available to ps-ers for
	# a small but exploitable time window.
#	#
# Standard input (STDIN) usage	# Standard input (STDIN) usage
# First line is USERNAME	# First line is USERNAME
# Second line is PASSWORD	# Second line is PASSWORD
# Third line is PASSWORD	# Third line is PASSWORD
	# Fouth line is the name of a file to which an error code will be written.
	# If the fourth line is omitted, no error file will be written.
	# In either case, the program Exits with the code as its Exit status.
	# The error file will just be a single line containing an
	# error code.
	#
	#
#	#
# Command-line arguments [USERNAME] [PASSWORD] [PASSWORD]	# Command-line arguments [USERNAME] [PASSWORD] [PASSWORD]
# Yes, but be very careful here (don't pass shell commands)	# Yes, but be very careful here (don't pass shell commands)
Line 75 use strict;	Line 81 use strict;
# ---------------------------------- Example usage inside another piece of code	# ---------------------------------- Example usage inside another piece of code
# Usage within code	# Usage within code
#	#
# $exitcode=	# $Exitcode=
# system("/home/httpd/perl/lcuseradd","NAME","PASSWORD1","PASSWORD2")/256;	# system("/home/httpd/perl/lcuseradd","NAME","PASSWORD1","PASSWORD2")/256;
# print "uh-oh" if $exitcode;	# print "uh-oh" if $Exitcode;

# ---------------------------------------------------- Description of functions	# ---------------------------------------------------- Description of functions
# enable_root_capability() : have setuid script run as root	# enable_root_capability() : have setuid script run as root
Line 85 use strict;	Line 91 use strict;
# try_to_lock() : make sure that another lcpasswd process isn't running	# try_to_lock() : make sure that another lcpasswd process isn't running

# ------------------------------------------------------------------ Exit codes	# ------------------------------------------------------------------ Exit codes
# These are the exit codes.	# These are the Exit codes.
# ( (0,"ok"),	# ( (0,"ok"),
# (1,"User ID mismatch. This program must be run as user 'www'"),	# (1,"User ID mismatch. This program must be run as user 'www'"),
# (2,"Error. This program needs 3 command-line arguments (username, ".	# (2,"Error. This program needs 3 command-line arguments (username, ".
Line 103 use strict;	Line 109 use strict;
# (12,"Error. Something went wrong with the addition of user ".	# (12,"Error. Something went wrong with the addition of user ".
# "\"$safeusername\"."),	# "\"$safeusername\"."),
# (13,"Error. Password mismatch."),	# (13,"Error. Password mismatch."),
	# (14, "Error filename is invalid"),
	# (15, "Error. Could not add home directory.")

# ------------------------------------------------------------- Initializations	# ------------------------------------------------------------- Initializations
# Security	# Security
Line 113 delete @ENV{qw(IFS CDPATH ENV BASH_ENV)}	Line 121 delete @ENV{qw(IFS CDPATH ENV BASH_ENV)}
# Do not print error messages.	# Do not print error messages.
my $noprint=1;	my $noprint=1;

	print "In lcuseradd\n" unless $noprint;

# ----------------------------- Make sure this process is running from user=www	# ----------------------------- Make sure this process is running from user=www
my $wwwid=getpwnam('www');	my $wwwid=getpwnam('www');
&disable_root_capability;	&disable_root_capability;
if ($wwwid!=$>) {	if ($wwwid!=$>) {
print("User ID mismatch. This program must be run as user 'www'\n")	print("User ID mismatch. This program must be run as user 'www'\n")
unless $noprint;	unless $noprint;
exit 1;	&Exit(1);
}	}

# ----------------------------------- Start running script with www permissions	# ----------------------------------- Start running script with www permissions
Line 129 if ($wwwid!=$>) {	Line 139 if ($wwwid!=$>) {
unless (&try_to_lock("/tmp/lock_lcpasswd")) {	unless (&try_to_lock("/tmp/lock_lcpasswd")) {
print "Error. Too many other simultaneous password change requests being ".	print "Error. Too many other simultaneous password change requests being ".
"made.\n" unless $noprint;	"made.\n" unless $noprint;
exit 4;	&Exit(4);
}	}

# ------- Error-check input, need 3 values (user name, password 1, password 2).	# ------- Error-check input, need 3 values (user name, password 1, password 2).
my @input;	my @input;
if (@ARGV==3) {	if (@ARGV>=3) {
@input=@ARGV;	@input=@ARGV;
}	} elsif (@ARGV) {
elsif (@ARGV) {	print("Error. This program needs at least 3 command-line arguments (username, ".
print("Error. This program needs 3 command-line arguments (username, ".	"password 1, password 2 [errorfile]).\n") unless $noprint;
"password 1, password 2).\n") unless $noprint;
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 2;	&Exit(2);
}	} else {
else {
@input=<>;	@input=<>;
if (@input!=3) {	if (@input < 3) {
print("Error. Three lines should be entered into standard input.\n")	print("Error. At least three lines should be entered into standard input.\n")
unless $noprint;	unless $noprint;
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 3;	&Exit(3);
}	}
map {chomp} @input;	foreach (@input) {chomp;}
}	}

my ($username,$password1,$password2)=@input;	my ($username,$password1,$password2, $error_file)=@input;
	print "Username = ".$username."\n" unless $noprint;
$username=~/^(\w+)$/;	$username=~/^(\w+)$/;
	print "Username after substitution - ".$username unless $noprint;
my $safeusername=$1;	my $safeusername=$1;
	print "Safe username = $safeusername \n" unless $noprint;

if (($username ne $safeusername) or ($safeusername!~/^[A-Za-z]/)) {	if (($username ne $safeusername) or ($safeusername!~/^[A-Za-z]/)) {
print "Error. The user name specified has invalid characters.\n"	print "Error. The user name specified $username $safeusername has invalid characters.\n"
unless $noprint;	unless $noprint;
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 9;	&Exit(9);
}	}
my $pbad=0;	my $pbad=0;
map {if ((ord($_)<32)\|\|(ord($_)>126)){$pbad=1;}} (split(//,$password1));	foreach (split(//,$password1)) {if ((ord($_)<32)\|\|(ord($_)>126)){$pbad=1;}}
map {if ((ord($_)<32)\|\|(ord($_)>126)){$pbad=1;}} (split(//,$password2));	foreach (split(//,$password2)) {if ((ord($_)<32)\|\|(ord($_)>126)){$pbad=1;}}
if ($pbad) {	if ($pbad) {
print "Error. A password entry had an invalid character.\n";	print "Error. A password entry had an invalid character.\n" unless $noprint;
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 10;	&Exit(10);
	}

	#
	# Safe the filename. For our case, it must only have alpha, numeric, period
	# and path sparators..
	#

	print "Error file is $error_file \n" unless $noprint;

	if($error_file) {
	if($error_file =~ /^([(\w)(\d)\.\/]+)$/) {
	print "Error file matched pattern $error_file : $1\n" unless $noprint;
	my $safe_error_file = $1; # Untainted I think.
	print "Error file after transform $safe_error_file\n"
	unless $noprint;
	if($error_file == $safe_error_file) {
	$error_file = $safe_error_file; # untainted error_file.
	} else {
	$error_file ="";
	print "Invalid error filename\n" unless $noprint;
	Exit(14);
	}

	} else {
	$error_file="";
	print "Invalid error filename\n" unless $noprint;
	Exit(14);
	}
}	}

# -- Only add user if we can create a brand new home directory (/home/username)
if (-e "/home/$safeusername") {	# -- Only add the user if they are >not< in /etc/passwd.
print "Error. User already exists.\n" unless $noprint;	# Used to look for the ability to create a new directory for the
	# user, however that disallows authentication changes from i
	# internal->fs.. so just check the passwd file instead.
	#
	my $not_found = system("cut -d: -f1 /etc/passwd \| grep -q \"^$safeusername\$\" ");
	if (!$not_found) {
	print "Error user already exists\n" unless $noprint;
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 11;	&Exit(11);
}	}



# -- Only add user if the two password arguments match.	# -- Only add user if the two password arguments match.

if ($password1 ne $password2) {	if ($password1 ne $password2) {
print "Error. Password mismatch.\n" unless $noprint;	print "Error. Password mismatch.\n" unless $noprint;
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 13;	&Exit(13);
}	}
	print "enabling root\n" unless $noprint;
# ---------------------------------- Start running script with root permissions	# ---------------------------------- Start running script with root permissions
&enable_root_capability;	&enable_root_capability;

# ------------------- Add user and make www a member of the user-specific group	# ------------------- Add group and user, and make www a member of the group
	# -- Add group

	print "adding group: $safeusername \n" unless $noprint;
	my $status = system('/usr/sbin/groupadd', $safeusername);
	if ($status) {
	print "Error. Something went wrong with the addition of group ".
	"\"$safeusername\".\n" unless $noprint;
	print "Final status of groupadd = $status\n";
	unlink('/tmp/lock_lcpasswd');
	&Exit(12);
	}
	my $gid = getgrnam($safeusername);

# -- Add user	# -- Add user
if (system('/usr/sbin/useradd','-c','LON-CAPA user',$safeusername)) {
	print "adding user: $safeusername \n" unless $noprint;
	my $status = system('/usr/sbin/useradd','-c','LON-CAPA user','-g',$gid,$safeusername);
	if ($status) {
print "Error. Something went wrong with the addition of user ".	print "Error. Something went wrong with the addition of user ".
"\"$safeusername\".\n" unless $noprint;	"\"$safeusername\".\n" unless $noprint;
	system("/usr/sbin/groupdel $safeusername");
	print "Final status of useradd = $status\n";
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 12;	&Exit(12);
}	}

	print "Done adding user\n" unless $noprint;
# Make www a member of that user group.	# Make www a member of that user group.
my $groups=`/usr/bin/groups www` or exit(6);	my $groups=`/usr/bin/groups www` or &Exit(6);
	# untaint
	my ($safegroups)=($groups=~/:\s*([\s\w]+)/);
	$groups=$safegroups;
chomp $groups; $groups=~s/^\S+\s+\:\s+//;	chomp $groups; $groups=~s/^\S+\s+\:\s+//;
my @grouplist=split(/\s+/,$groups);	my @grouplist=split(/\s+/,$groups);
my @ugrouplist=grep {!/www\|$safeusername/} @grouplist;	my @ugrouplist=grep {!/www\|$safeusername/} @grouplist;
my $gl=join(',',(@ugrouplist,$safeusername));	my $gl=join(',',(@ugrouplist,$safeusername));
	print "Putting www in user's group\n" unless $noprint;
if (system('/usr/sbin/usermod','-G',$gl,'www')) {	if (system('/usr/sbin/usermod','-G',$gl,'www')) {
print "Error. Could not make www a member of the group ".	print "Error. Could not make www a member of the group ".
"\"$safeusername\".\n" unless $noprint;	"\"$safeusername\".\n" unless $noprint;
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
exit 6;	&Exit(6);
}	}

# ---------------------------------------------------------------- Set password	# ---------------------------------------------------------------- Set password
Line 217 if (system('/usr/sbin/usermod','-G',$gl,	Line 289 if (system('/usr/sbin/usermod','-G',$gl,
unlink('/tmp/lock_lcpasswd');	unlink('/tmp/lock_lcpasswd');
&disable_root_capability;	&disable_root_capability;
($>,$<)=($wwwid,$wwwid);	($>,$<)=($wwwid,$wwwid);
	print "Opening lcpasswd pipeline\n" unless $noprint;
open OUT,"\|/home/httpd/perl/lcpasswd";	open OUT,"\|/home/httpd/perl/lcpasswd";
print OUT $safeusername;	print OUT $safeusername;
print OUT "\n";	print OUT "\n";
Line 226 print OUT $password1;	Line 299 print OUT $password1;
print OUT "\n";	print OUT "\n";
close OUT;	close OUT;
if ($?) {	if ($?) {
exit 8;	print "abnormal Exit from close lcpasswd\n" unless $noprint;
	&Exit(8);
}	}
($>,$<)=($wwwid,0);	($>,$<)=($wwwid,0);
&enable_root_capability;	&enable_root_capability;

	# Check if home directory exists for user
	# If not, create one.
	if (!-e "/home/$safeusername") {
	if (!mkdir("/home/$safeusername",0710)) {
	print "Error. Could not add home directory for ".
	"\"$safeusername\".\n" unless $noprint;
	unlink('/tmp/lock_lcpasswd');
	&Exit(15);
	}
	}

# ------------------------------ Make final modifications to the user directory	# ------------------------------ Make final modifications to the user directory
# -- Add a public_html file with a stand-in index.html file	# -- Add a public_html file with a stand-in index.html file

# system('/bin/chmod','-R','0660',"/home/$safeusername");	if (-d "/home/$safeusername") {
system('/bin/chmod','0710',"/home/$safeusername");	system('/bin/chmod','-R','0660',"/home/$safeusername");
mkdir "/home/$safeusername/public_html",0755;	system('/bin/chmod','0710',"/home/$safeusername");
system('/bin/chmod','02770',"/home/$safeusername/public_html");	mkdir "/home/$safeusername/public_html",0755;
open OUT,">/home/$safeusername/public_html/index.html";	open OUT,">/home/$safeusername/public_html/index.html";
print OUT<<END;	print OUT<<END;
<html>	<html>
<head>	<head>
<title>$safeusername</title>	<title>$safeusername</title>
</head>	</head>
<body>	<body>
<h1>$safeusername</h1>	<h1>Construction Space</h1>
<p>	<h3>$safeusername</h3>
Learning Online Network
</p>
<p>
This area provides for:
</p>
<ul>
<li>resource construction</li>
<li>resource publication</li>
<li>record-keeping</li>
</ul>
</body>	</body>
</html>	</html>
END	END
close OUT;	close OUT;
system('/bin/chown','-R',"$safeusername:$safeusername","/home/$safeusername");	}

	#
	# In order to allow the loncapa daemons appropriate access
	# to public_html, Top level and public_html directories should
	# be owned by safeusername:safeusername as should the smaple index.html..
	print "lcuseradd ownership\n" unless $noprint;
	system('/bin/chown','-R',"$safeusername:$safeusername","/home/$safeusername"); # First set std ownership on everything.
	&set_public_html_permissions("/home/$safeusername/public_html");
	# system('/bin/chown',"$safeusername:www","/home/$safeusername"); # Now adust top level...
	# system('/bin/chown','-R',"$safeusername:www","/home/$safeusername/public_html"); # And web dir.
	# ---------------------------------------------------- Gracefull Apache Restart
	my $pidfile;
	if (-e '/var/run/httpd.pid') {
	$pidfile = '/var/run/httpd.pid';
	} elsif (-e '/var/run/httpd2.pid') { #Apache 2 on SuSE 10.1 and SLES10
	$pidfile = '/var/run/httpd2.pid';
	}

	if ($pidfile) {
	print "lcuseradd Apache restart\n" unless $noprint;
	open(PID,"<$pidfile");
	my $pid=<PID>;
	close(PID);
	$pid=~ /(\D+)/;
	my $safepid = $1;
	if ($pid) {
	system('kill','-USR1',"$safepid");
	}
	}
# -------------------------------------------------------- Exit script	# -------------------------------------------------------- Exit script
	print "lcuseradd Exiting\n" unless $noprint;
&disable_root_capability;	&disable_root_capability;
exit 0;	&Exit(0);

# ---------------------------------------------- Have setuid script run as root	# ---------------------------------------------- Have setuid script run as root
sub enable_root_capability {	sub enable_root_capability {
if ($wwwid==$>) {	if ($wwwid==$>) {
($<,$>)=($>,$<);	($<,$>)=($>,0);
($(,$))=($),$();	($(,$))=($),0);
}	} else {
else {
# root capability is already enabled	# root capability is already enabled
}	}
	if ($wwwid == $>) {
	print("Failed to become root\n") unless $noprint;
	} else {
	print("Became root\n") unless $noprint;
	}
return $>;	return $>;
}	}

Line 284 sub disable_root_capability {	Line 392 sub disable_root_capability {
if ($wwwid==$<) {	if ($wwwid==$<) {
($<,$>)=($>,$<);	($<,$>)=($>,$<);
($(,$))=($),$();	($(,$))=($),$();
}	} else {
else {
# root capability is already disabled	# root capability is already disabled
}	}
}	}
Line 314 sub try_to_lock {	Line 421 sub try_to_lock {
}	}
sleep 3;	sleep 3;
$lastpid=$currentpid;	$lastpid=$currentpid;
}	} else {
else {
last;	last;
}	}
if ($_==10) {	if ($_==10) {
Line 327 sub try_to_lock {	Line 433 sub try_to_lock {
close LOCK;	close LOCK;
return 1;	return 1;
}	}
	# Called by File::Find::find for each file examined.
	#
	# Untaint the file and, if it is a directory,
	# chmod it to 02770
	#
	sub set_permission {
	$File::Find::name =~ /^(.*)$/;
	my $safe_name = $1; # Untainted filename...

	print "$safe_name" unless $noprint;
	if(-d $safe_name) {
	print " - directory" unless $noprint;
	chmod(02770, $safe_name);
	}
	print "\n" unless $noprint;

	}
	#
	# Set up the correct permissions for all files in the
	# user's public htmldir. We just do a chmod -R 0660 ... for
	# the ordinary files. The we use File::Find
	# to pop through the directory tree changing directories only
	# to 02770:
	#
	sub set_public_html_permissions {
	my ($topdir) = @_;

	# Set the top level dir permissions (I'm not sure if find
	# will enumerate it specifically), correctly and all
	# files and dirs to the 'ordinary' file permissions:

	system("chmod -R 0660 $topdir");
	chmod(02770, $topdir);

	# Now use find to locate all directories under $topdir
	# and set their modes to 02770...
	#
	print "Find file\n " unless $noprint;
	File::Find::find({"untaint" => 1,
	"untaint_pattern" => qr(/^(.*)$/),
	"untaint_skip" => 1,
	"no_chdir" => 1,
	"wanted" => \&set_permission }, "$topdir");


	}

	#-------------------------- Exit...
	#
	# Write the file if the error_file is defined. Regardless
	# Exit with the status code.
	#
	sub Exit {
	my ($code) = @_; # Status code.

	# TODO: Ensure the error file is owned/deletable by www:www:

	&disable_root_capability(); # We run unprivileged to write the error file.

	print "Exiting with status $code error file is $error_file\n" unless $noprint;
	if($error_file) {
	open(FH, ">$error_file");
	print FH "$code\n";
	close(FH);
	}
	exit $code;
	}

=head1 NAME	=head1 NAME

FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>

Removed from v.1.18
changed lines
	Added in v.1.41