Edit: /usr/local/bin/shasum (9287B)
#!/usr/bin/perl
## shasum: filter for computing SHA digests (ref. sha1sum/md5sum)
##
## Copyright (C) 2003-2016 Mark Shelor, All Rights Reserved
##
## Version: 5.96
## Wed Jul 27 20:04:34 MST 2016
## shasum SYNOPSIS adapted from GNU Coreutils sha1sum. Add
## "-a" option for algorithm selection,
## "-U" option for Universal Newlines support,
## "-0" option for reading bit strings, and
## "-p" option for portable digests (to be deprecated).
BEGIN { pop @INC if $INC[-1] eq '.' }
use strict;
use warnings;
use Fcntl;
use Getopt::Long;
my $POD = <<'END_OF_POD';
=head1 NAME
shasum - Print or Check SHA Checksums
=head1 SYNOPSIS
Usage: shasum [OPTION]... [FILE]...
Print or check SHA checksums.
With no FILE, or when FILE is -, read standard input.
-a, --algorithm 1 (default), 224, 256, 384, 512, 512224, 512256
-b, --binary read in binary mode
-c, --check read SHA sums from the FILEs and check them
-t, --text read in text mode (default)
-U, --UNIVERSAL read in Universal Newlines mode
produces same digest on Windows/Unix/Mac
-0, --01 read in BITS mode
ASCII '0' interpreted as 0-bit,
ASCII '1' interpreted as 1-bit,
all other characters ignored
-p, --portable read in portable mode (to be deprecated)
The following two options are useful only when verifying checksums:
-s, --status don't output anything, status code shows success
-w, --warn warn about improperly formatted checksum lines
-h, --help display this help and exit
-v, --version output version information and exit
When verifying SHA-512/224 or SHA-512/256 checksums, indicate the
algorithm explicitly using the -a option, e.g.
shasum -a 512224 -c checksumfile
The sums are computed as described in FIPS PUB 180-4. When checking,
the input should be a former output of this program. The default
mode is to print a line with checksum, a character indicating type
(`*' for binary, ` ' for text, `U' for UNIVERSAL, `^' for BITS, `?'
for portable), and name for each FILE.
Report shasum bugs to mshelor@cpan.org
=head1 DESCRIPTION
Running I
is often the quickest way to compute SHA message
digests. The user simply feeds data to the script through files or
standard input, and then collects the results from standard output.
The following command shows how to compute digests for typical inputs
such as the NIST test vector "abc":
perl -e "print qq(abc)" | shasum
Or, if you want to use SHA-256 instead of the default SHA-1, simply say:
perl -e "print qq(abc)" | shasum -a 256
Since I mimics the behavior of the combined GNU I,
I, I, I, and I programs,
you can install this script as a convenient drop-in replacement.
Unlike the GNU programs, I encompasses the full SHA standard by
allowing partial-byte inputs. This is accomplished through the BITS
option (I<-0>). The following example computes the SHA-224 digest of
the 7-bit message I<0001100>:
perl -e "print qq(0001100)" | shasum -0 -a 224
=head1 AUTHOR
Copyright (c) 2003-2016 Mark Shelor .
=head1 SEE ALSO
I is implemented using the Perl module L or
L.
=cut
END_OF_POD
my $VERSION = "5.96";
sub usage {
my($err, $msg) = @_;
$msg = "" unless defined $msg;
if ($err) {
warn($msg . "Type shasum -h for help\n");
exit($err);
}
my($USAGE) = $POD =~ /SYNOPSIS(.+?)^=/sm;
$USAGE =~ s/^\s*//;
$USAGE =~ s/\s*$//;
$USAGE =~ s/^ //gm;
print $USAGE, "\n";
exit($err);
}
## Sync stdout and stderr by forcing a flush after every write
select((select(STDOUT), $| = 1)[0]);
select((select(STDERR), $| = 1)[0]);
## Collect options from command line
my ($alg, $binary, $check, $text, $status, $warn, $help, $version);
my ($portable, $BITS, $reverse, $UNIVERSAL, $versions);
eval { Getopt::Long::Configure ("bundling") };
GetOptions(
'b|binary' => \$binary, 'c|check' => \$check,
't|text' => \$text, 'a|algorithm=i' => \$alg,
's|status' => \$status, 'w|warn' => \$warn,
'h|help' => \$help, 'v|version' => \$version,
'p|portable' => \$portable,
'0|01' => \$BITS,
'R|REVERSE' => \$reverse,
'U|UNIVERSAL' => \$UNIVERSAL,
'V|VERSIONS' => \$versions,
) or usage(1, "");
## Deal with help requests and incorrect uses
usage(0)
if $help;
usage(1, "shasum: Ambiguous file mode\n")
if scalar(grep {defined $_}
($binary, $portable, $text, $BITS, $UNIVERSAL)) > 1;
usage(1, "shasum: --warn option used only when verifying checksums\n")
if $warn && !$check;
usage(1, "shasum: --status option used only when verifying checksums\n")
if $status && !$check;
## Try to use Digest::SHA. If not installed, use the slower
## but functionally equivalent Digest::SHA::PurePerl instead.
## If option -R is invoked, reverse the module preference,
## i.e. try Digest::SHA::PurePerl first, then Digest::SHA.
my @MODS = qw(Digest::SHA Digest::SHA::PurePerl);
@MODS[0, 1] = @MODS[1, 0] if $reverse;
my $module;
for (@MODS) {
my $mod = $_;
if (eval "require $mod") {
$module = $mod;
last;
}
}
die "shasum: Unable to find " . join(" or ", @MODS) . "\n"
unless defined $module;
## Default to SHA-1 unless overridden by command line option
$alg = 1 unless defined $alg;
grep { $_ == $alg } (1, 224, 256, 384, 512, 512224, 512256)
or usage(1, "shasum: Unrecognized algorithm\n");
## Display version information if requested
if ($version) {
print "$VERSION\n";
exit(0);
}
if ($versions) {
print "shasum $VERSION\n";
print "$module ", eval "\$${module}::VERSION", "\n";
print "perl ", defined $^V ? sprintf("%vd", $^V) : $], "\n";
exit(0);
}
## Try to figure out if the OS is DOS-like. If it is,
## default to binary mode when reading files, unless
## explicitly overridden by command line "--text" or
## "--UNIVERSAL" or "--portable" options.
my $isDOSish = ($^O =~ /^(MSWin\d\d|os2|dos|mint|cygwin)$/);
if ($isDOSish) { $binary = 1 unless $text || $UNIVERSAL || $portable }
my $modesym = $binary ? '*' : ($UNIVERSAL ? 'U' :
($BITS ? '^' : ($portable ? '?' : ' ')));
## Read from STDIN (-) if no files listed on command line
@ARGV = ("-") unless @ARGV;
## sumfile($file): computes SHA digest of $file
sub sumfile {
my $file = shift;
my $mode = $binary ? 'b' : ($UNIVERSAL ? 'U' :
($BITS ? '0' : ($portable ? 'p' : '')));
my $digest = eval { $module->new($alg)->addfile($file, $mode) };
if ($@) { warn "shasum: $file: $!\n"; return }
$digest->hexdigest;
}
## %len2alg: maps hex digest length to SHA algorithm
my %len2alg = (40 => 1, 56 => 224, 64 => 256, 96 => 384, 128 => 512);
$len2alg{56} = 512224 if $alg == 512224;
$len2alg{64} = 512256 if $alg == 512256;
## unescape: convert backslashed filename to plain filename
sub unescape {
$_ = shift;
s/\\\\/\0/g;
s/\\n/\n/g;
return if /\\/;
s/\0/\\/g;
return $_;
}
## verify: confirm the digest values in a checksum file
sub verify {
my $checkfile = shift;
my ($err, $fmt_errs, $read_errs, $match_errs) = (0, 0, 0, 0);
my ($num_lines, $num_files) = (0, 0);
my ($bslash, $sum, $fname, $rsp, $digest);
local *FH;
$checkfile eq '-' and open(FH, '< -')
and $checkfile = 'standard input'
or sysopen(FH, $checkfile, O_RDONLY)
or die "shasum: $checkfile: $!\n";
while () {
next if /^#/; s/\n$//; s/^[ \t]+//; $num_lines++;
$bslash = s/^\\//;
($sum, $modesym, $fname) =
/^([\da-fA-F]+)[ \t]([ *?^U])([^\0]*)/;
$alg = defined $sum ? $len2alg{length($sum)} : undef;
$fname = unescape($fname) if defined $fname && $bslash;
if (grep { ! defined $_ } ($alg, $sum, $modesym, $fname)) {
$alg = 1 unless defined $alg;
warn("shasum: $checkfile: $.: improperly " .
"formatted SHA$alg checksum line\n") if $warn;
$fmt_errs++;
next;
}
$fname =~ s/\r$// unless -e $fname;
$rsp = "$fname: "; $num_files++;
($binary, $text, $UNIVERSAL, $BITS, $portable) =
map { $_ eq $modesym } ('*', ' ', 'U', '^', 'p');
unless ($digest = sumfile($fname)) {
$rsp .= "FAILED open or read\n";
$err = 1; $read_errs++;
}
else {
if (lc($sum) eq $digest) { $rsp .= "OK\n" }
else { $rsp .= "FAILED\n"; $err = 1; $match_errs++ }
}
print $rsp unless $status;
}
close(FH);
unless ($num_files) {
$alg = 1 unless defined $alg;
warn("shasum: $checkfile: no properly formatted " .
"SHA$alg checksum lines found\n");
$err = 1;
}
elsif (! $status) {
warn("shasum: WARNING: $fmt_errs line" . ($fmt_errs>1?
's are':' is') . " improperly formatted\n") if $fmt_errs;
warn("shasum: WARNING: $read_errs listed file" .
($read_errs>1?'s':'') . " could not be read\n") if $read_errs;
warn("shasum: WARNING: $match_errs computed checksum" .
($match_errs>1?'s':'') . " did NOT match\n") if $match_errs;
}
return($err == 0);
}
## Verify or compute SHA checksums of requested files
my($file, $digest);
my $STATUS = 0;
for $file (@ARGV) {
if ($check) { $STATUS = 1 unless verify($file) }
elsif ($digest = sumfile($file)) {
if ($file =~ /[\n\\]/) {
$file =~ s/\\/\\\\/g; $file =~ s/\n/\\n/g;
$digest = "\\$digest";
}
print "$digest $modesym", "$file\n";
}
else { $STATUS = 1 }
}
exit($STATUS)