From: skamkar <skamkar@ef4ab9da-24cd-11de-8aaa-f3a34680c41f>
Date: Sat, 8 Aug 2009 05:50:54 +0000 (+0000)
Subject: look for binary data in other data
X-Git-Tag: v1.0.0~528
X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/commitdiff_plain/14ac2f1ea0abcc336e698c5f99b36468d6d22cac?ds=inline

look for binary data in other data
---

diff --git a/tools/rfidtest.pl b/tools/rfidtest.pl
new file mode 100644
index 00000000..db898d32
--- /dev/null
+++ b/tools/rfidtest.pl
@@ -0,0 +1,119 @@
+#!/usr/bin/perl
+# -samy kamkar, rfid@samy.pl
+
+use strict;
+
+die "usage: $0 <file with data> <binary to search for>\n" unless @ARGV == 2;
+
+my ($file, $search) = @ARGV;
+$search =~ s/\s//g;
+
+# sure, these aren't perfect, but simplifies usability if you know what you're doing
+# if in doubt, use binary
+
+# binary, cool
+if ($search =~ /^[01]+$/) { }
+# decimal
+elsif ($search =~ /^\d+$/)
+{
+	$search = unpack("B*", pack("N", $search));
+	$search =~ s/^0*//;
+}
+# hex
+elsif ($search =~ /^[\da-fA-F]+$/)
+{
+	$search = unpack("B*", pack("H*", $search));
+	$search =~ s/^0*//;
+}
+# ascii
+else
+{
+	$search = unpack("B*", $search);
+	$search =~ s/^0*//;
+}
+
+
+# read file contents
+open(F, "<$file") || die "Can't read $file: $!";
+my $data = join("", <F>);
+close(F);
+
+# convert to binary
+$data =~ s/\s//g;
+# binary, great
+if ($data =~ /^[01]+$/) { }
+elsif ($data =~ /^[\da-fA-F]+$/)
+{
+	$data = unpack("B*", pack("H*", $data));
+	$search =~ s/^0*//;
+}
+else
+{
+	die "Seriously. What sort of data is this file? Binary or hex only please.\n";
+}
+
+
+# search every method we know how
+print "Testing normally...\n";
+test_all($data, $search);
+
+print "Testing with flipped bits...\n";
+test_all($data, $search, 1);
+
+# now try manchester demodulating
+my @bits = split(//, $data);
+my $man;
+my $last = 0;
+for (my $i = 1; $i < @bits; $i++)
+{
+	# if we changed, flip our bit
+	if ($bits[$i-1] == 1)
+	{
+		$last ^= 1;
+	}
+	$man .= $last;
+}
+
+print "Testing with manchester demodulation...\n";
+test_all($man, $search);
+
+print "Testing with flipped manchester demodulation...\n";
+test_all($man, $search, 1);
+
+
+sub test_all
+{
+	my ($data, $search, $flip) = @_;
+	
+	if ($flip)
+	{
+		$data =~ s/(.)/$1 ^ 1/eg;
+	}
+	
+	# first just see if our data is in the stream
+	if ($data =~ /$search/)
+	{
+		print "Found $search in our stream ($data)\n";
+	}
+
+	# try removing parity every 4 and 8 bits
+	foreach my $parity (4, 8)
+	{
+		# try removing a parity bit every $parity bits
+		# test by cutting off a bit at a time in case we're in the wrong bit position
+		my $tmp = $data;
+		foreach (1 .. $parity)
+		{
+			my $test = $tmp;
+			$test =~ s/(.{$parity})./$1/g;
+		
+			if ($test =~ /$search/)
+			{
+				print "Found $search with parity every " . ($parity + 1) . "th bit, round $_ out of $parity ($test)\n";
+			}
+		
+			# chop of a bit to change our bit position next round
+			$tmp =~ s/^.//;
+		}
+	}
+}