/usr/bin/logontime is in hxtools 20170430-1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48  | #!/usr/bin/perl
#
#	longontime - simple wtmp analyzer
#	written by Jan Engelhardt, 2004-2007
#
#	This program is free software; you can redistribute it and/or
#	modify it under the terms of the WTF Public License version 2 or
#	(at your option) any later version.
#
use Getopt::Long;
use strict;
my %Total;
my $ARG_time;
&Getopt::Long::Configure(qw(bundling));
&GetOptions("t" => \$ARG_time);
open(IN, "last -ax |");
while (defined(my $l = <IN>)) {
	chomp $l;
	my($user, $dur) = ($l =~ /^(\w+)\s+.+?\((.*?)\)/);
	if ($user eq "") {
		next;
        }
	my($h, $m) = split(/:/o, $dur);
	$Total{$user} += $h * 60 + $m;
}
close IN;
if ($ARG_time) {
	# Time sort
	foreach my $u (sort { $Total{$b} <=> $Total{$a} } keys %Total) {
		printf "%-8s: %3ud %2uh %2um (%5um)\n",
                      $u, int($Total{$u} / 1440), int($Total{$u} / 60 % 24),
                      int($Total{$u} % 60), $Total{$u};
	}
} else {
	# Alphabetical sort
	foreach my $u (sort keys %Total) {
		printf "%-8s: %3ud %2uh %2um (%5um)\n",
		       $u, int($Total{$u} / 86400),
		       int($Total{$u} / 60 % 86400), int($Total{$u} % 60),
		       $Total{$u};
	}
}
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