From cda056bb9e8a6b6345cbd1a4034b71f3e3dcd527 Mon Sep 17 00:00:00 2001
From: "roel@libnfc.org" <roel@libnfc.org@ef4ab9da-24cd-11de-8aaa-f3a34680c41f>
Date: Thu, 7 Mar 2013 12:23:31 +0000
Subject: [PATCH] added all files for mfkeys

---
 tools/mfkey/mfkey32.c              | 72 ++++++++++++++++++++++++++++++
 tools/mfkey/{mfkey.c => mfkey64.c} | 15 ++++---
 2 files changed, 82 insertions(+), 5 deletions(-)
 create mode 100755 tools/mfkey/mfkey32.c
 rename tools/mfkey/{mfkey.c => mfkey64.c} (84%)

diff --git a/tools/mfkey/mfkey32.c b/tools/mfkey/mfkey32.c
new file mode 100755
index 00000000..0e64a3e8
--- /dev/null
+++ b/tools/mfkey/mfkey32.c
@@ -0,0 +1,72 @@
+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
+#define llx PRIx64
+#define lli PRIi64
+
+// Test-file: test2.c
+#include "crapto1.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+int main (int argc, char *argv[]) {
+  struct Crypto1State *s,*t;
+  uint64_t key;     // recovered key
+  uint32_t uid;     // serial number
+  uint32_t nt;      // tag challenge
+  uint32_t nr0_enc; // first encrypted reader challenge
+  uint32_t ar0_enc; // first encrypted reader response
+  uint32_t nr1_enc; // second encrypted reader challenge
+  uint32_t ar1_enc; // second encrypted reader response
+  uint32_t ks2;     // keystream used to encrypt reader response
+
+  printf("MIFARE Classic key recovery - based 32 bits of keystream\n");
+  printf("Recover key from two 32-bit reader authentication answers only!\n\n");
+
+  if (argc < 7) {
+    printf(" syntax: %s <uid> <nt> <{nr_0}> <{ar_0}> <{nr_1}> <{ar_1}>\n\n",argv[0]);
+    return 1;
+  }
+
+  sscanf(argv[1],"%x",&uid);
+  sscanf(argv[2],"%x",&nt);
+  sscanf(argv[3],"%x",&nr0_enc);
+  sscanf(argv[4],"%x",&ar0_enc);
+  sscanf(argv[5],"%x",&nr1_enc);
+  sscanf(argv[6],"%x",&ar1_enc);
+
+  printf("Recovering key for:\n");
+  printf("    uid: %08x\n",uid);
+  printf("     nt: %08x\n",nt);
+  printf(" {nr_0}: %08x\n",nr0_enc);
+  printf(" {ar_0}: %08x\n",ar0_enc);
+  printf(" {nr_1}: %08x\n",nr1_enc);
+  printf(" {ar_1}: %08x\n",ar1_enc);
+
+	// Generate lfsr succesors of the tag challenge
+  printf("\nLFSR succesors of the tag challenge:\n");
+  printf("  nt': %08x\n",prng_successor(nt, 64));
+  printf(" nt'': %08x\n",prng_successor(nt, 96));
+
+  // Extract the keystream from the messages
+  printf("\nKeystream used to generate {ar} and {at}:\n");
+  ks2 = ar0_enc ^ prng_successor(nt, 64);
+  printf("  ks2: %08x\n",ks2);
+
+	s = lfsr_recovery32(ar0_enc ^ prng_successor(nt, 64), 0);
+  
+	for(t = s; t->odd | t->even; ++t) {
+		lfsr_rollback_word(t, 0, 0);
+		lfsr_rollback_word(t, nr0_enc, 1);
+		lfsr_rollback_word(t, uid ^ nt, 0);
+		crypto1_get_lfsr(t, &key);
+		crypto1_word(t, uid ^ nt, 0);
+		crypto1_word(t, nr1_enc, 1);
+		if (ar1_enc == (crypto1_word(t, 0, 0) ^ prng_successor(nt, 64))) {
+      printf("\nFound Key: [%012"llx"]\n\n",key);
+			break;
+		}
+	}
+  free(s);
+
+  return 0;
+}
diff --git a/tools/mfkey/mfkey.c b/tools/mfkey/mfkey64.c
similarity index 84%
rename from tools/mfkey/mfkey.c
rename to tools/mfkey/mfkey64.c
index 71e35589..448cb2ac 100755
--- a/tools/mfkey/mfkey.c
+++ b/tools/mfkey/mfkey64.c
@@ -1,11 +1,15 @@
+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
+#define llx PRIx64
+#define lli PRIi64
+
 // Test-file: test2.c
 #include "crapto1.h"
 #include <stdio.h>
 
 int main (int argc, char *argv[]) {
   struct Crypto1State *revstate;
-  uint64_t lfsr;
-  uint8_t* plfsr = (uint8_t*)&lfsr;
+  uint64_t key;     // recovered key
   uint32_t uid;     // serial number
   uint32_t nt;      // tag challenge
   uint32_t nr_enc;  // encrypted reader challenge
@@ -14,7 +18,8 @@ int main (int argc, char *argv[]) {
   uint32_t ks2;     // keystream used to encrypt reader response
   uint32_t ks3;     // keystream used to encrypt tag response
 
-  printf("MIFARE Classic key recovery\n\n");
+  printf("MIFARE Classic key recovery - based 64 bits of keystream\n");
+  printf("Recover key from only one complete authentication!\n\n");
 
   if (argc < 6) {
     printf(" syntax: %s <uid> <nt> <{nr}> <{ar}> <{at}>\n\n",argv[0]);
@@ -58,8 +63,8 @@ int main (int argc, char *argv[]) {
   lfsr_rollback_word(revstate, 0, 0);
   lfsr_rollback_word(revstate, nr_enc, 1);
   lfsr_rollback_word(revstate, uid ^ nt, 0);
-  crypto1_get_lfsr(revstate, &lfsr);
-  printf("\nFound Key: [%02x %02x %02x %02x %02x %02x]\n\n",plfsr[5],plfsr[4],plfsr[3],plfsr[2],plfsr[1],plfsr[0]);
+  crypto1_get_lfsr(revstate, &key);
+  printf("\nFound Key: [%012"llx"]\n\n",key);
   crypto1_destroy(revstate);
 
   return 0;
-- 
2.39.2