From dcab7a01c06f150ae8d4ff8dbf8b84ba58bcccf7 Mon Sep 17 00:00:00 2001
From: Dobrica Pavlinusic <dpavlin@rot13.org>
Date: Mon, 31 Jan 2011 22:49:41 +0100
Subject: [PATCH] easily dump unique mifare cards, remembering keys

---
 nfc-card-dumper.pl | 87 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 87 insertions(+)
 create mode 100755 nfc-card-dumper.pl

diff --git a/nfc-card-dumper.pl b/nfc-card-dumper.pl
new file mode 100755
index 0000000..5403ada
--- /dev/null
+++ b/nfc-card-dumper.pl
@@ -0,0 +1,87 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+
+use RFID::Libnfc::Reader;
+use RFID::Libnfc::Constants;
+use File::Slurp;
+use Digest::MD5 qw(md5_hex);
+
+use Data::Dump qw(dump);
+
+my $keyfile = shift @ARGV;
+
+my $r = RFID::Libnfc::Reader->new(debug => 1);
+if ($r->init()) {
+    printf ("Reader: %s\n", $r->name);
+    my $tag = $r->connect(IM_ISO14443A_106);
+
+    if ($tag) {
+        $tag->dump_info;
+    } else {
+        warn "No TAG";
+        exit -1;
+    }
+
+	my $uid = sprintf "%02x%02x%02x%02x", unpack('C4', $tag->{_nai}->abtUid);
+	# @{ $tag->uid }; # FIXME this doesn't work with tags which have 00 in UID!
+
+	warn "UID: $uid\n";
+
+	$keyfile ||= "cards/$uid.key";
+
+	if ( -e $keyfile ) {
+		warn "# loading keys from $keyfile";
+	    $tag->load_keys($keyfile);
+		warn "## _keys = ", dump($tag->{_keys});
+	}
+
+    $tag->select if ($tag->can("select")); 
+
+	my $card;
+
+	print STDERR "reading";
+    for (my $i = 0; $i < $tag->blocks; $i++) {
+        if (my $data = $tag->read_block($i)) {
+            # if we are dumping an ultralight token, 
+            # we receive 16 bytes (while a block is 4bytes long)
+            # so we can skip next 3 blocks
+            $i += 3 if ($tag->type eq "ULTRA");
+			$card .= $data;
+			print STDERR "$i ";
+        } else {
+            die $tag->error."\n";
+        }
+    }
+	print STDERR "done\n";
+
+	# re-insert keys into dump
+	my $keys = $tag->{_keys} || die "can't find _keys";
+	foreach my $i ( 0 .. $#$keys ) {
+		my $o = $i * 0x40 + 0x30;
+		last if $o > length($card);
+		$card
+			= substr($card, 0,   $o) . $keys->[$i]->[0]
+			. substr($card, $o+6, 4) . $keys->[$i]->[1]
+			. substr($card, $o+16)
+			;
+		warn "sector $i keys re-inserted at $o\n";
+	}
+
+	my $md5 = md5_hex($card);
+	if ( glob "cards/$uid.md5.*" ) {
+		warn "SKIPPING, same dump allready exits\n";
+	} else {
+
+		my $out_file = "cards/$uid.$md5";
+		write_file $out_file, $card;
+		print "$out_file ", -s $out_file, " bytes\n";
+		if ( ! -e "cards/$uid.key" ) {
+			symlink $out_file, "cards/$uid.key" || die "cards/$uid.key: $!";
+			warn "using keys as default for card $uid\n";
+		}
+		system "./mifare-mad.pl $out_file | vi -R -";
+	}
+
+}
+
-- 
2.20.1