diff --git a/tools/test_modules/m00400.pm b/tools/test_modules/m00400.pm
new file mode 100644
index 000000000..4d127b2d0
--- /dev/null
+++ b/tools/test_modules/m00400.pm
@@ -0,0 +1,63 @@
+#!/usr/bin/env perl
+
+##
+## Author......: See docs/credits.txt
+## License.....: MIT
+##
+
+my $itoa64_1 = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+
+use strict;
+use warnings;
+
+use Authen::Passphrase::PHPass;
+
+sub module_constraints { [[0, 255], [8, 8], [0, 55], [8, 8], [-1, -1]] }
+
+sub module_generate_hash
+{
+  my $word = shift;
+  my $salt = shift;
+  my $iter = shift;
+
+  my $cost = 11;
+
+  if (length ($iter))
+  {
+    $cost = $iter;
+  }
+
+  my $ppr = Authen::Passphrase::PHPass->new
+  (
+    cost       => $cost,
+    salt       => $salt,
+    passphrase => $word,
+  );
+
+  my $hash_buf = $ppr->as_rfc2307;
+
+  return substr ($hash_buf, 7);
+}
+
+sub module_verify_hash
+{
+  my $line = shift;
+
+  my ($hash, $word) = split (':', $line);
+
+  return unless defined $hash;
+  return unless defined $word;
+
+  my $salt = substr ($hash, 4, 8);
+
+  # iterations = 2 ^ cost (where cost == $iter)
+  my $iter = index ($itoa64_1, substr ($hash, 3, 1));
+
+  my $word_packed = pack_if_HEX_notation ($word);
+
+  my $new_hash = module_generate_hash ($word_packed, $salt, $iter);
+
+  return (substr ($hash, 0, 3) . substr ($new_hash, 3), $word);
+}
+
+1;