CHG: 'lf cotag demod' - now finds FC/CN Thanks to @marshmellow42

[proxmark3-svn] / armsrc / des.c

diff --git a/armsrc/des.c b/armsrc/des.c
index dbe62da995ba5107854ef38ed476d2ca469fc16a..513f89bfeb9c17124361aafc047074cd0ba08519 100644 (file)
--- a/armsrc/des.c
+++ b/armsrc/des.c
@@ -25,8 +25,8 @@
  * \license     GPLv3 or later
  * 
  */
-#include <stdint.h>
-#include <string.h>
+
+#include "des.h"
 
 const uint8_t sbox[256]  = {
   /* S-box 1 */
@@ -210,7 +210,7 @@ void permute(const uint8_t *ptable, const uint8_t *in, uint8_t *out){
        for(byte=0; byte<ob; ++byte){
                uint8_t x,t=0;
                for(bit=0; bit<8; ++bit){
-                       x=*ptable++ -1 ;
+                       x = *ptable++ - 1;
                                t<<=1;
                        if((in[x/8]) & (0x80>>(x%8)) ){
                                t|=0x01;
@@ -274,7 +274,7 @@ uint32_t des_f(uint32_t r, uint8_t* kr){
        uint64_t data;
        uint8_t *sbp; /* sboxpointer */ 
        permute((uint8_t*)e_permtab, (uint8_t*)&r, (uint8_t*)&data);
-       for(i=0; i<7; ++i)
+       for(i=0; i<6; ++i)
                ((uint8_t*)&data)[i] ^= kr[i];
        
        /* Sbox substitution */
@@ -378,43 +378,58 @@ void tdes_dec(void* out, void* in, const uint8_t* key){
        des_dec(out, out, (uint8_t*)key + 0);
 }
 
-void tdes_2key_enc(void* out, const void* in, size_t length, const void* key){
+ void tdes_2key_enc(void* out, const void* in, size_t length, const void* key, unsigned char iv[8]){
 
        if( length % 8 ) return; 
-       
+
+       uint8_t i;
        uint8_t* tin = (uint8_t*) in;
        uint8_t* tout = (uint8_t*) out;
        
        while( length > 0 )
        {
+               for( i = 0; i < 8; i++ )
+                               tout[i] = (unsigned char)( tin[i] ^ iv[i] );
+               
                des_enc(tout,  tin, (uint8_t*)key + 0);
                des_dec(tout, tout, (uint8_t*)key + 8);
                des_enc(tout, tout, (uint8_t*)key + 0);
                
+               memcpy( iv, tout, 8 );
+               
                tin  += 8;
                tout += 8;
                length -= 8;
        }
-}
-
-void tdes_2key_dec(void* out, const void* in, size_t length, const void* key){
+ }
+ 
+ void tdes_2key_dec(void* out, const void* in, size_t length, const void* key, unsigned char iv[8]){
        
        if( length % 8 ) return; 
 
+       uint8_t i;
+       unsigned char temp[8];
        uint8_t* tin = (uint8_t*) in;
        uint8_t* tout = (uint8_t*) out;
        
        while( length > 0 )
        {
+               memcpy( temp, tin, 8 );
+               
                des_dec(tout,  tin, (uint8_t*)key + 0);
                des_enc(tout, tout, (uint8_t*)key + 8);
                des_dec(tout, tout, (uint8_t*)key + 0);          
 
+               for( i = 0; i < 8; i++ )
+                       tout[i] = (unsigned char)( tout[i] ^ iv[i] );
+
+               memcpy( iv, temp, 8 );
+               
                tin  += 8;
                tout += 8;
                length -= 8;
        }
-}
+ }
 
 
 /******************************************************************************/