Mini Shell

#!/usr/local/cpanel/3rdparty/bin/perl

# cpanel - scripts/secureit                        Copyright 2022 cPanel, L.L.C.
#                                                           All rights reserved.
# copyright@cpanel.net                                         http://cpanel.net
# This code is subject to the cPanel license. Unauthorized copying is prohibited

use strict;
use warnings;

use Cpanel::Usage        ();
use Cpanel::Init::Simple ();
use Cpanel::OS           ();

# Parse command line.
my $dryrun  = 0;
my $try_rpm = 0;
Cpanel::Usage::wrap_options( \@ARGV, \&usage, { 'dryrun' => \$dryrun, 'fast' => \$try_rpm } );

exit 0 if -e '/var/cpanel/nosecureit' || -e '/var/cpanel/disabled/secureit';

#----------------------------------------------------------------------

my @serviceList = ( 'portmap', 'lpd', 'apmd', 'gpm', 'innd', 'pcmcia', 'smb', 'xfs', 'ypbind' );

{
    local $SIG{__WARN__} = sub { };    # we expect some of these to fail
    foreach my $serviceName (@serviceList) {
        Cpanel::Init::Simple::call_cpservice_with( $serviceName => qw/stop disable/ );

    }
}

#----------------------------------------------------------------------

my @OKSUID = (qw/crontab cpwrap jailshell passwd ksu su suexec suphp exim sendmail fpexe wrapper sudo sudoedit gpasswd sendmail.sendmail cagefs_enter.proxied/);
my @OKGUID = (qw/crontab procmail wall man sendmail sendmail.sendmail screen/);

# to use rpm to find [sg]uid files --fast needs to be passed and we've got to be an RPM based linux
if ( $try_rpm && Cpanel::OS::is_rpm_based() ) {
    cleanse_sguid_rpm();
}
else {
    cleanse_sguid_find();
}

sub cleanse_sguid_find {
    print "Finding set[gu]id files via find\n";

    my @SUID = `nice -19 /usr/bin/find /usr /sbin /bin -uid 0 -perm /4000`;
    my @GUID = `nice -19 /usr/bin/find /usr /sbin /bin -uid 0 -perm /2000`;
    chomp @SUID;
    chomp @GUID;

    foreach my $item (@SUID) {
        next if ( $item =~ m{^/usr/local/cpanel} );    # Skip cpanel files.
        next if ( $item =~ /modsec_audit/ );
        $item =~ s/\n//g;
        my $itemok = 0;
        foreach my $match (@OKSUID) {
            if ( $item =~ /${match}$/ ) {
                $itemok = 1;
            }
        }
        if ( $itemok == 0 ) {
            print "Removing suid from $item\n";
            system( 'chmod', 'u-s', $item ) if ( !$dryrun );
        }
    }

    foreach my $item (@GUID) {
        next if ( $item =~ m{^/usr/local/cpanel} );    # Skip cpanel files.
        next if ( $item =~ /modsec_audit/ );
        $item =~ s/\n//g;
        my $itemok = 0;
        foreach my $match (@OKGUID) {
            if ( $item =~ /${match}$/ ) {
                $itemok = 1;
            }
        }
        if ( $itemok == 0 ) {
            print "Removing guid from $item\n";
            system( 'chmod', 'g-s', $item ) if ( !$dryrun );
        }
    }
    return;
}

sub cleanse_sguid_rpm {
    print "Finding set[gu]id files via the RPM database\n";

    my @RPMFILES = `rpm -qa --queryformat '[%{FILEMODES} %{FILENAMES}\n]'`;
    chomp @RPMFILES;
    @RPMFILES = grep { !m{^\d+\s+/usr/local/cpanel} } @RPMFILES;    # Strip out cpanel installed rpms

  SUID: foreach my $item (@RPMFILES) {
        my ( $perm, $file ) = split( " ", $item, 2 ) or next;
        next if ( $perm !~ m/^\d+$/ );                              # Lines that don't mention files (%{FILENAMES})
        next if ( !( $perm & 04000 ) );
        next if !-e $file;

        foreach my $match (@OKSUID) {
            if ( $file =~ m{/${match}$} ) {
                print "Skipping suid removal for $file\n";
                next SUID;
            }
        }
        print "Removing suid from $file\n";

        system( 'chmod', 'u-s', $file ) if ( !$dryrun );
    }

  GUID: foreach my $item (@RPMFILES) {
        my ( $perm, $file ) = split( " ", $item, 2 ) or next;
        next if ( $perm !~ m/^\d+$/ );    # Lines that don't mention files (%{NAME})
        next if ( !( $perm & 02000 ) );
        next if !-e $file;

        foreach my $match (@OKGUID) {
            if ( $file =~ m{/${match}$} ) {
                print "Skipping guid removal for $file\n";
                next GUID;
            }
        }
        print "Removing guid from $file\n";
        system( 'chmod', 'g-s', $file ) if ( !$dryrun );
    }
    return;
}

sub usage {
    print qq{Usage: $0 [options]};
    print qq{

    Options:
      --help     Brief help message
      --dryrun   Do not make any changes but show what would happen.
      --fast     On RPM systems, do not walk the file system, instead,
                 get the file permissions list from the RPM DB. This is
                 only useful once. After that the DB will be out of sync
                 with the file system. This option is mostly useful
                 during install


};
    exit 1;
}