/usr/bin/crc32 is in libarchive-zip-perl 1.30-7.
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  | #!/usr/bin/perl
eval 'exec /usr/bin/perl  -S $0 ${1+"$@"}'
    if 0; # not running under some shell
# Computes and prints to stdout the CRC-32 values of the given files
use strict;
use lib qw( blib/lib lib );
use Archive::Zip;
use FileHandle;
my $totalFiles = scalar(@ARGV);
foreach my $file (@ARGV) {
    if ( -d $file ) {
        warn "$0: ${file}: Is a directory\n";
        next;
    }
    my $fh = FileHandle->new();
    if ( !$fh->open( $file, 'r' ) ) {
        warn "$0: $!\n";
        next;
    }
    binmode($fh);
    my $buffer;
    my $bytesRead;
    my $crc = 0;
    while ( $bytesRead = $fh->read( $buffer, 32768 ) ) {
        $crc = Archive::Zip::computeCRC32( $buffer, $crc );
    }
    printf( "%08x", $crc );
    print("\t$file") if ( $totalFiles > 1 );
    print("\n");
}
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