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

# cpanel - scripts/smartcheck                      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

package scripts::smartcheck;

use strict;
use warnings;
use Cpanel::DataStore        ();
use Getopt::Param            ();
use Cpanel::StringFunc::Trim ();
use Cpanel::SafeRun::Dynamic ();

our $bin                       = '/usr/local/cpanel/3rdparty/bin/smartctl';
our $last_sent                 = '/var/cpanel/last_smartcheck_msg_alert';
our $fstab_file                = '/etc/fstab';
our $cust_d_file               = '/var/cpanel/smartcheck_custom_dash_d.yaml';
our $disable_file              = '/var/cpanel/disablesmartcheck';
our $smart_enabled_rgx_21      = 'Drive supports S.M.A.R.T. and is enabled';
our $smart_enabled_rgx_5x      = '.*SMART.*Enabled|Available.*has.*SMART';
our $smart_enabled_rgx_6x      = '.*SMART.*Enabled|Available.*has.*SMART';
our $smart_enabled_rgx_default = '.*SMART.*Enabled|Available.*has.*SMART';

sub get_smartctl {
    my %smart = (
        'url'         => 'http://smartmontools.sourceforge.net/',
        'version_cmd' => '-V',
        'version_rgx' => '^smartctl\s*(?:version)?\s*',

        # 2.1 is retained for historical reasons and may be removed without notice
        '2.1' => {
            'smart_enabled_cmd' => '-i',
            'smart_enabled_rgx' => $smart_enabled_rgx_21,
            'errors_only'       => '-l',
            'ok_drive_rgx'      => [qw(/sd /hd)],
        },

        # 5.37 is the last version of smartmontools directly distributed with cP/WHM
        '5.37' => {
            'smart_enabled_cmd' => '-i',
            'smart_enabled_rgx' => $smart_enabled_rgx_5x,
            'errors_only'       => '-q errorsonly -H -l selftest -l error',
            'ok_drive_rgx'      => [qw(/sd /hd)],
        },

        # 5.42 is the latest version of smartmontools provided via yum for CentOS 5
        '5.42' => {
            'smart_enabled_cmd' => '-i',
            'smart_enabled_rgx' => $smart_enabled_rgx_5x,
            'errors_only'       => '-q errorsonly -H -l selftest -l error',
            'ok_drive_rgx'      => [qw(/sd /hd)],
        },

        # 5.43 is the latest version of smartmontools provided via yum for CentOS 6
        '5.43' => {
            'smart_enabled_cmd' => '-i',
            'smart_enabled_rgx' => $smart_enabled_rgx_5x,
            'errors_only'       => '-q errorsonly -H -l selftest -l error',
            'ok_drive_rgx'      => [qw(/sd /hd)],
        },

        # 6.2 is the latest version of smartmontools provided via yum for CentOS 7
        '6.2' => {
            'smart_enabled_cmd' => '-i',
            'smart_enabled_rgx' => $smart_enabled_rgx_6x,
            'errors_only'       => '-q errorsonly -H -l selftest -l error',
            'ok_drive_rgx'      => [qw(/sd /hd)],
        },

        # default is suitable for all known versions of 5.x and 6.x
        'default' => {
            'smart_enabled_cmd' => '-i',
            'smart_enabled_rgx' => $smart_enabled_rgx_default,
            'errors_only'       => '-q errorsonly -H -l selftest -l error',
            'ok_drive_rgx'      => [qw(/sd /hd)],
        },
    );
    return \%smart;
}

sub _get_enabled_string {
    my ( $smart, $vrs, $dsk ) = @_;
    my $disk_enabled = '';
    Cpanel::SafeRun::Dynamic::livesaferun(
        'prog'      => [ $bin, split( /\s+/, $smart->{$vrs}->{'smart_enabled_cmd'} ), $dsk ],
        'formatter' => sub {
            my ($line) = @_;
            $disk_enabled .= $line;
            return '';
        },
    );
    return $disk_enabled;
}

sub is_smart_enabled {
    my ( $smart, $vrs, $dsk ) = @_;
    my $disk_enabled = _get_enabled_string( $smart, $vrs, $dsk );
    return ( $disk_enabled =~ m/$smart->{$vrs}->{'smart_enabled_rgx'}/i ) ? 1 : undef;
}

sub _extract_version {
    my ( $line, $quit_saferun_loop_sr ) = @_;

    my $vrs;
    my $smart = get_smartctl();

    # handle if $line is undef
    if ($line) {
        if ( $line =~ m/^$smart->{'version_rgx'}\s*(\d+\.\d+)/ ) {
            $vrs = $1;
            ${$quit_saferun_loop_sr} = 1;
        }
    }

    # if the version can't be determined or is not found in the smartctl hash, use 'default'
    $vrs = 'default' if ( !$vrs || !exists $smart->{$vrs} );

    return $vrs;
}

sub get_smart_version {
    my $smart = shift;
    my ( $vrs, $output );
    Cpanel::SafeRun::Dynamic::livesaferun(
        'prog'      => [ $bin, split( /\s+/, $smart->{'version_cmd'} ) ],
        'formatter' => sub {
            my ($line) = @_;
            $output .= $line;
            return '';
        },
    );
    $vrs = _extract_version($output);

    return $vrs;
}

sub run {

    my %smart = %{ get_smartctl() };

    my $custom_d = Cpanel::DataStore::fetch_ref($cust_d_file);

    my $param = Getopt::Param->new(
        {
            'help_coderef' => sub {
                print <<"SMARTCHECK_HELP";
$0 - check the status of your harddrive(s) with smartctl.

   --help    this screen
   --quiet   bare minimum output
   --noemail output to screen only, do not send email

TROUBLESHOOTING

If you have a hard drive that keeps getting this output via $0:

  "Checking /dev/sda....S.M.A.R.T does not appear to be enabled for this device."

You may confirm directly if your hard drive supports SMART using the following command:

  # smartctl -i /dev/YOURHDD

After this, if you are certain it has SMART support enabled, then you can tell $0
to specify a given drive type to smartctl using a simple YAML file:

  $cust_d_file (described in detail in the following section)

If after verifying using smartctl directly that your drive is supported and you have added
a custom configuration, it is possible that $0 is simply not properly detecting
that your drive is supported. In this case, please file a bug report.

CONFIGURATION FILE

You may add custom configurations, per drive, to $cust_d_file"

This file may contain simple key/value values where the key is the drive and the value is the value of
that drive's type.

For example to tell smartctl that /dev/sda and /dev/sdb is an "ata" we create this YAML file:

  ---
  /dev/sda: ata
  /dev/sdb: ata

Then the next time it's run we'll see this output instead:

  Checking /dev/sda....
      Adding custom '-d ata' flag for /dev/sda from $cust_d_file
  Ok

For more information on -d options available for supporting drives behind RAID controllers, see:

  http://www.smartmontools.org/wiki/Supported_RAID-Controllers

While YAML files are plain text, its best to initialize the configuration file are shown below.

To write the initial entry into $cust_d_file:

  perl -MYAML::Syck=DumpFile -e 'DumpFile("$cust_d_file", {"/dev/sda"=>"ata"});'

To dump the current has to the screen:

  perl -MYAML::Syck=LoadFile -MData::Dumper -e 'print Dumper(LoadFile("$cust_d_file"));'

Note: Subsequent entries should be handed added since the above two commands overrite any existing file.

$cust_d_file may also be used to add additional drives that do not have entrieds
directly in $fstab_file.
SMARTCHECK_HELP
                exit;
            },
        }
    );

    require Digest::SHA;

    my %drive_lookup;
    my $msg      = '';
    my $didhowdy = 0;
    my $quiet    = $param->get_param('quiet')  ? 1 : 0;
    my $nomail   = $param->get_param('nomail') ? 1 : 0;
    my $debug    = 0;

  FINDSMARTCTL:
    if ( !-l $bin ) {
        for my $smartctl (qw(/usr/sbin/smartctl /usr/local/sbin/smartctl)) {
            if ( -e $smartctl ) {

                #if an existing exists and we still have the old, replace it with a link
                if ( -e $bin ) {
                    unlink $bin or die "Could not remove old cPanel smartctl: $!";
                }
                system 'ln', '-s', $smartctl, $bin;
                last;
            }
        }
    }

    my $link = readlink($bin) || 'smartctl';

  DONTRUNIF:
    {
        if ( !-e $bin ) {    # or -l or -x instead ???
            exit;
        }

        if ( -e $disable_file ) {
            exit;
        }
    }

    my $vrs = get_smart_version( \%smart );
    $smart{'BINVER'} = ( $vrs ne 'default' ) ? $vrs : 'unknown';

    # unsupported SCSI was here

    my @mounts;
  FINDDISKS:
    {
        Cpanel::SafeRun::Dynamic::livesaferun(
            'prog'      => ['mount'],
            'formatter' => sub {
                my ($line) = @_;
                push @mounts, $line;
                return '';
            },
        );

        open my $fstab,, '<', $fstab_file or die "Could not open $fstab_file: $!";
        my @fstab_lines = <$fstab>;
        close $fstab;

        for my $mount_lines ( @mounts, @fstab_lines ) {
            next if $mount_lines =~ m{ (?:cdrom | floppy | noauto) }xms;
            my ($drive) = $mount_lines =~ /^(\/\S+)/;
            if ($drive) {
                $drive =~ s{\d+$}{}g;
                $drive_lookup{$drive} = 1;
            }
        }

        # add additional possible entries from custom config
        for my $dsk ( keys %$custom_d ) {
            $drive_lookup{$dsk} = 1;
        }
    }

  CHECKDISKS:
    {
        for my $dsk ( sort keys %drive_lookup ) {
            next if !grep { $dsk =~ m/\Q$_\E/ } @{ $smart{$vrs}->{'ok_drive_rgx'} };
            if ( !$didhowdy ) {
                print qq{Using smartcheck version profile "$vrs" for smartctl ($smart{'BINVER'})\n}
                  if !$quiet;
                $didhowdy++;
            }

            print "Checking $dsk...." unless $quiet;
            if ( exists $custom_d->{$dsk} && $custom_d->{$dsk} =~ m{^\S+$} ) {
                print "\n\tAdding custom '-d $custom_d->{$dsk}' flag for $dsk from $cust_d_file\n" if !$quiet;
                $smart{$vrs}->{'smart_enabled_cmd'} = "-d $custom_d->{$dsk} $smart{$vrs}->{'smart_enabled_cmd'}";
            }

            if ( is_smart_enabled( \%smart, $vrs, $dsk ) ) {
                my $error = '';
                Cpanel::SafeRun::Dynamic::livesaferun(
                    'prog'      => [ $bin, split( /\s+/, $smart{$vrs}->{'errors_only'} ), $dsk ],
                    'formatter' => sub {
                        my ($line) = @_;
                        $error .= $line;
                        return '';
                    },
                );
                $error = Cpanel::StringFunc::Trim::ws_trim($error);

                if ($error) {
                    $msg .= <<"MSG_END";
                S.M.A.R.T Errors on $dsk
                From Command: $link $smart{$vrs}->{'errors_only'} $dsk
                $error
                ----END $dsk--

MSG_END
                    print "\nErrors:\n $error\n\n" if !$quiet;
                }
                else {
                    print "Ok\n" if !$quiet;
                }
            }
            else {
                print "S.M.A.R.T does not appear to be enabled for this device.\n"
                  if !$quiet;
            }
        }
    }

    if ( $msg && -e $last_sent ) {
        $msg = '' if Digest::SHA->new(512)->addfile($last_sent)->hexdigest eq Digest::SHA::sha512_hex($msg);
    }

  ALERT_FAILINGDISKS:
    {
        if ( $msg ne '' ) {
            if ( open my $last_fh, '>', $last_sent ) {
                print {$last_fh} $msg;
                close $last_fh;
            }
            else {
                warn "Could not open $last_sent for writing: $!";
            }

            my $subject = '[cPanel smartcheck] Possible Hard Drive Failure Soon';
            my $smsg    = <<"SMART_END";
IMPORTANT: Do not ignore this email! !!!! READ IT THOUROUGHLY !!

Your system's smartctl utility has detected some errors.
(see the "---- smartctl report --" section below for details).
You should investigate those errors according to `man smartctl`
and documentation at $smart{'url'}
including their mailing list. You can disable this check by doing:
 `touch /var/cpanel/disablesmartcheck`
and reenable it at anytime by removing that file.
If you do find issues you should consider using smartd to
monitor your drives instead of/along with this script.

This email was generated by the cPanel smartcheck script and is
reporting errors from your S.M.A.R.T enabled drives with the
given commands below. It is up to you to investigate further
and take appropriate steps:

  !!!! Do not submit tickets or bug reports if you get this email.
    Use the avenues outlined in this email to deal with your
    system's S.M.A.R.T setup. !!

To begin your troubleshooting you may want to run
 `/usr/local/cpanel/scripts/smartcheck --nomail` as root via SSH.

---- smartctl report --
$msg
SMART_END

            if ( !$nomail ) {
                require Cpanel::Notify;
                Cpanel::Notify::notification_class(
                    'class'            => 'Check::Smart',
                    'application'      => 'Check::Smart',
                    'constructor_args' => [
                        'origin'       => 'smartcheck',
                        'attach_files' => [ { name => 'SMART-log.txt', content => \$msg } ],
                    ]
                );
            }

            if ($debug) {
                print "This was emailed unless you used --nomail:\n" . "Subject: $subject\n\n$smsg";
            }
        }
    }
    return;
}

run() if !caller();

1;

__END__

=head1 NAME

/scripts/smartcheck

=head1 USAGE

  /scripts/smartcheck [--help] | [--quiet --noemail]

=head1 REQUIRED ARGUMENTS

None

=head1 OPTIONS

=over 4

=item -- help

List the help section, then exit immediately.

=item --quiet

Do not output the normal dialog to STDOUT.

=item --noemail

Do not send an email alert if a disk is found to be failing.

=back

=head1 DESCRIPTION

This utility is a wrapper around smartmontool's smartctl tool. It is run regularly
as part of C</scripts/maintenance>. It may be run independently from the commandline
or as part of a more frequently occurring crontab entry.

If hard drives that are SMART enabled show signs of impending failure, this utility
will generate the necessary warnings necessary to alert the admin of this server.

=head1 DIAGNOSTICS

None

=head1 CONFIGURATION

C</var/cpanel/smartcheck_custom_dash_d.yaml> may be used for two purposes.

First, it may be used to define the type (passed to smartctl's -d flag) for a specific
drive if smartctl is unable to determine this without help.

Secondly, the configuration file may be used to define SMART enabled hard drives that
are not directly listed in the system's C</etc/fstab> file.

For more information on -d options available for supporting drives behind RAID
controllers, please visit:

L<http://www.smartmontools.org/wiki/Supported_RAID-Controllers>

=head1 EXIT STATUS

Exit status is 0 (success) unless an unexpected error occurs, in which case it will
die (255).

=head1 DEPENDENCIES

This utility requires that a modern version of smartmontools be installed. It has been
tested to work with versions 5.x and 6.x, although there is legacy support for version
2.1.

=head1 INCOMPATIBILITIES

None

=head1 SEE ALSO

The help section displayed using the C<--help> option is very handy.

=head1 BUGS AND LIMITATIONS

SMART checks are only made on SMART enabled hard drives that have device names
beginning with "hd" and "sd".

=head1 LICENSE AND COPYRIGHT

   Copyright 2022 cPanel, L.L.C.