#!/usr/local/bin/perl

# passwd replacement for solaris < 10
# try to make users select a stronger password
# copyright 2009.05.04 jeremy kister http://jeremy.kister.net./
# v2009061901

# to install, simply:
# mv /usr/bin/passwd /usr/bin/passwd.orig
# chmod 0 /usr/bin/passwd.orig
# mv passwd.pl /usr/bin/passwd
# chown root:sys /usr/bin/passwd
# chmod 6555 /usr/bin/passwd
#
# set CRYPT_DEFAULT=1 in /etc/security/policy.conf

use strict;
use IO::Socket::SSL;

my $DEBUG = 1;

$SIG{INT} = $SIG{QUIT} = $SIG{HUP} = sub { cleanup(); };

if($DEBUG){ $IO::Socket::SSL::DEBUG = 1; }

my $sock = IO::Socket::SSL->new( Listen => 5,
                                 LocalAddr => '0.0.0.0',
                                 LocalPort => 269
                                 Proto     => 'tcp',
                                 Reuse     => 1,
                                 SSL_verify_mode => 0x01,
                               );
unless($sock){
    debug( "unable to create socket: ", &IO::Socket::SSL::errstr );
    exit(0);
}

debug( "socket created: ($sock)" );

while(1){
	debug( "waiting for connection." );

	while( my $s = $sock->accept() ){

		open(TSTMP, ">/etc/stmp.$$") || die "cannot write to /etc/stmp.$$: $!\n";
		close TSTMP;
		chmod(0600, "/etc/stmp.$$") || die "cannot set file mode on /etc/stmp.$$: $!\n";

		my $have_link;
		for(1..5){
		    if( link("/etc/stmp.$$", "/etc/stmp") ){
		        $have_link = 1;
		        last;
		    }else{
 		       sleep 2;
		    }
		}

		unless($have_link){
		    print "passwd: Sorry, could not obtain stmp lock.\n";
		    exit_evil();
		}

		open(SHADOW, "/etc/shadow") || die "cannot read shadow file: $!\n";
		my @shadow = <SHADOW>;
		close SHADOW;

        open(STMP, ">>/etc/stmp") || die "could not append to stmp: $!\n";
        foreach(@shadow){
            if(/^$user:/){
                print STMP "${user}:${ncrypt}:${days}::::::\n";
            }else{
                print STMP;
            }
        }
        close STMP;
   
        rename("/etc/stmp","/etc/shadow") || die "cannot rename stmp to shadow: $!\n";
        unlink("/etc/stmp.$$") || die "cannot unlink stmp.$$: $!\n";
        chmod(0400, "/etc/shadow") || die "cannot set file mode on /etc/shadow: $!\n";

        system("cd /var/yp ; /usr/local/bin/make >/dev/null 2>&1");

}else{
    print "passwd: Sorry, wrong passwd\n";
    cleanup();
}

sub cleanup {
    unlink("/etc/stmp.$$");
    unlink("/etc/stmp") if($have_link);
}

sub debug {
	my $msg = join('', @_);

	warn "$msg\n" if($DEBUG);
}