X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/fecd8202a5ad638db4c1ba088842390e78ef52db..3ad48540d4d77f50cc62d16acb78f17019ef431d:/client/loclass/cipher.c diff --git a/client/loclass/cipher.c b/client/loclass/cipher.c index aad77a2e..aefb5df5 100644 --- a/client/loclass/cipher.c +++ b/client/loclass/cipher.c @@ -21,17 +21,32 @@ * along with IClassCipher. If not, see . ****************************************************************************/ +#include "cipher.h" +#include "cipherutils.h" #include #include #include #include #include -#include "loclass/cipher.h" -#include "loclass/cipherutils.h" -#include "loclass/ikeys.h" - +#include +#include "fileutils.h" 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 * is defined as @@ -160,8 +175,6 @@ void output(uint8_t* k,State s, BitstreamIn* in, BitstreamOut* out) { 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); @@ -190,72 +203,48 @@ 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); - } - -void printarr(char * name, uint8_t* arr, int len) +void doMAC(uint8_t cc_nr[12],uint8_t div_key[8], uint8_t mac[4]) { - int i ; - printf("uint8_t %s[] = {", name); - for(i =0 ; i< len ; i++) - { - printf("0x%02x,",*(arr+i)); - } - printf("};\n"); + // Reversed "on-the-wire" data + uint8_t cc_nr_r[12] = {0}; + reverse_arraycopy(cc_nr, cc_nr_r,12); + BitstreamIn bitstream = {cc_nr_r,12 * 8,0}; + uint8_t dest [8]= {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); + return; } 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}; - // But actually, that must be reversed, it's "on-the-wire" data - reverse_arraybytes(cc_nr,sizeof(cc_nr)); - //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 { - 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 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