Compiler correctly identified a buffer overflow, fixed that and made the code use...

[proxmark3-svn] / client / loclass / cipher.c

diff --git a/client/loclass/cipher.c b/client/loclass/cipher.c
index aad77a2e0f68aace3199655d8ad2df8333c8fe28..7c9cc873a019f1ae67c9c84ba8cabd789d4e88bd 100644 (file)
--- a/client/loclass/cipher.c
+++ b/client/loclass/cipher.c
@@ -1,5 +1,17 @@
 /*****************************************************************************
 /*****************************************************************************

- * This file is part of iClassCipher. It is a reconstructon of the cipher engine
+ * WARNING
+ *
+ * THIS CODE IS CREATED FOR EXPERIMENTATION AND EDUCATIONAL USE ONLY. 
+ * 
+ * USAGE OF THIS CODE IN OTHER WAYS MAY INFRINGE UPON THE INTELLECTUAL 
+ * PROPERTY OF OTHER PARTIES, SUCH AS INSIDE SECURE AND HID GLOBAL, 
+ * AND MAY EXPOSE YOU TO AN INFRINGEMENT ACTION FROM THOSE PARTIES. 
+ * 
+ * THIS CODE SHOULD NEVER BE USED TO INFRINGE PATENTS OR INTELLECTUAL PROPERTY RIGHTS. 
+ *
+ *****************************************************************************
+ *
+ * This file is part of loclass. It is a reconstructon of the cipher engine

  * used in iClass, and RFID techology.
  *
  * The implementation is based on the work performed by
  * used in iClass, and RFID techology.
  *
  * The implementation is based on the work performed by


@@ -18,19 +30,38 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License

- * along with IClassCipher.  If not, see <http://www.gnu.org/licenses/>.
+ * along with loclass.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ * 
+ * 

  ****************************************************************************/
 
  ****************************************************************************/
 

-#include <stdio.h>
+
+#include "cipher.h"
+#include "cipherutils.h"

 #include <stdlib.h>
 #include <string.h>
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdbool.h>
 #include <stdint.h>

-#include "loclass/cipher.h"
-#include "loclass/cipherutils.h"
-#include "loclass/ikeys.h"
+#ifndef ON_DEVICE
+#include "fileutils.h"
+#endif

 
 

-uint8_t keytable[] = { 0,0,0,0,0,0,0,0};
+
+/**
+* Definition 1 (Cipher state). A cipher state of iClass s is an element of F 40/2
+* consisting of the following four components:
+*      1. the left register l = (l 0 . . . l 7 ) ∈ F 8/2 ;
+*      2. the right register r = (r 0 . . . r 7 ) ∈ F 8/2 ;
+*      3. the top register t = (t 0 . . . t 15 ) ∈ F 16/2 .
+*      4. the bottom register b = (b 0 . . . b 7 ) ∈ F 8/2 .
+**/
+typedef struct {
+       uint8_t l;
+       uint8_t r;
+       uint8_t b;
+       uint16_t t;
+} State;

 
 /**
 *      Definition 2. The feedback function for the top register T : F 16/2 → F 2
 
 /**
 *      Definition 2. The feedback function for the top register T : F 16/2 → F 2


@@ -160,8 +191,6 @@ void output(uint8_t* k,State s, BitstreamIn* in,  BitstreamOut* out)
        {
                return;
        }
        {
                return;
        }

-       //printf("bitsleft %d" , bitsLeft(in));
-       //printf(" %0d", s.r >> 2 & 1);

        pushBit(out,(s.r >> 2) & 1);
        //Remove first bit
        uint8_t x0 = headBit(in);
        pushBit(out,(s.r >> 2) & 1);
        //Remove first bit
        uint8_t x0 = headBit(in);


@@ -190,72 +219,54 @@ void MAC(uint8_t* k, BitstreamIn input, BitstreamOut out)
        BitstreamIn input_32_zeroes = {zeroes_32,sizeof(zeroes_32)*8,0};
        State initState = suc(k,init(k),&input);
        output(k,initState,&input_32_zeroes,&out);
        BitstreamIn input_32_zeroes = {zeroes_32,sizeof(zeroes_32)*8,0};
        State initState = suc(k,init(k),&input);
        output(k,initState,&input_32_zeroes,&out);

-

 }
 
 }
 

-
-void printarr(char * name, uint8_t* arr, int len)
+void doMAC(uint8_t *cc_nr_p, uint8_t *div_key_p, uint8_t mac[4])

 {
 {

-       int i ;
-       printf("uint8_t %s[] = {", name);
-       for(i =0 ;  i< len ; i++)
-       {
-               printf("0x%02x,",*(arr+i));
-       }
-       printf("};\n");
-}
+       uint8_t cc_nr[13] = { 0 };
+    uint8_t div_key[8];
+       //cc_nr=(uint8_t*)malloc(length+1);
+
+       memcpy(cc_nr,cc_nr_p,12);
+    memcpy(div_key,div_key_p,8);

 
 

+       reverse_arraybytes(cc_nr,12);
+       BitstreamIn bitstream = {cc_nr,12 * 8,0};
+    uint8_t dest []= {0,0,0,0,0,0,0,0};
+    BitstreamOut out = { dest, sizeof(dest)*8, 0 };
+    MAC(div_key,bitstream, out);
+    //The output MAC must also be reversed
+    reverse_arraybytes(dest, sizeof(dest));
+    memcpy(mac, dest, 4);
+       //free(cc_nr);
+    return;
+}
+#ifndef ON_DEVICE

 int testMAC()
 {
 int testMAC()
 {

+       prnlog("[+] Testing MAC calculation...");

 
        //From the "dismantling.IClass" paper:
        uint8_t cc_nr[] = {0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0,0,0,0};
 
        //From the "dismantling.IClass" paper:
        uint8_t cc_nr[] = {0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0,0,0,0};

-       // But actually, that must be reversed, it's "on-the-wire" data
-       reverse_arraybytes(cc_nr,sizeof(cc_nr));
-

        //From the paper
        //From the paper

-       uint8_t div_key[] = {0xE0,0x33,0xCA,0x41,0x9A,0xEE,0x43,0xF9};
-       uint8_t correct_MAC[] = {0x1d,0x49,0xC9,0xDA};
+       uint8_t div_key[8] = {0xE0,0x33,0xCA,0x41,0x9A,0xEE,0x43,0xF9};
+       uint8_t correct_MAC[4] = {0x1d,0x49,0xC9,0xDA};

 
 

-       BitstreamIn bitstream = {cc_nr,sizeof(cc_nr) * 8,0};
-       uint8_t dest []= {0,0,0,0,0,0,0,0};
-       BitstreamOut out = { dest, sizeof(dest)*8, 0 };
-       MAC(div_key,bitstream, out);
-       //The output MAC must also be reversed
-       reverse_arraybytes(dest, sizeof(dest));
+       uint8_t calculated_mac[4] = {0};
+       doMAC(cc_nr,div_key, calculated_mac);

 
 

-       if(false && memcmp(dest, correct_MAC,4) == 0)
+       if(memcmp(calculated_mac, correct_MAC,4) == 0)

        {
        {

-               printf("MAC calculation OK!\n");
+               prnlog("[+] MAC calculation OK!");

 
        }else
        {
 
        }else
        {

-               printf("MAC calculation failed\n");
-               printarr("Calculated_MAC", dest, 4);
-               printarr("Correct_MAC   ", correct_MAC, 4);
+               prnlog("[+] FAILED: MAC calculation failed:");
+               printarr("    Calculated_MAC", calculated_mac, 4);
+               printarr("    Correct_MAC   ", correct_MAC, 4);

                return 1;
        }
                return 1;
        }

+

        return 0;
 }
        return 0;
 }

-
-int calc_iclass_mac(uint8_t *cc_nr_p, int length, uint8_t *div_key_p, uint8_t *mac)
-{
-    uint8_t *cc_nr;
-    uint8_t div_key[8];
-    cc_nr=(uint8_t*)malloc(length+1);
-    memcpy(cc_nr,cc_nr_p,length);
-    memcpy(div_key,div_key_p,8);
-    
-       reverse_arraybytes(cc_nr,length);
-       BitstreamIn bitstream = {cc_nr,length * 8,0};
-       uint8_t dest []= {0,0,0,0,0,0,0,0};
-       BitstreamOut out = { dest, sizeof(dest)*8, 0 };
-       MAC(div_key,bitstream, out);
-       //The output MAC must also be reversed
-       reverse_arraybytes(dest, sizeof(dest));
-       
-       printf("Calculated_MAC\t%02x%02x%02x%02x\n", dest[0],dest[1],dest[2],dest[3]);
-       memcpy(mac,dest,4);
-       free(cc_nr);
-       return 1;
-}
\ No newline at end of file
+#endif