proxmark3/armsrc/optimized_cipher.h
Philippe Teuwen d19754567d summer restructuring:
* .h include only the strict minimum for their own parsing
  * this forces all files to include explicitment their needs and not count on far streched dependencies
  * this helps Makefile to rebuild only the minimum
  * according to this rule, most standalone .h are now gone
  * big app.h is gone
  * remove seldom __cplusplus, if c++ happens, everything will have to be done properly anyway
* all unrequired include were removed
* split common/ into common/ (client+arm) and common_arm/ (os+bootloader)
  * bring zlib to common/
  * bring stuff not really/not yet used in common back to armsrc/ or client/
  * bring liblua into client/
  * bring uart into client/
  * move some portions of code around (dbprint, protocols,...)
* rename unused files into *_disabled.[ch] to make it explicit
* rename soft Uarts between 14a, 14b and iclass, so a standalone could use several without clash
* remove PrintAndLogDevice
* move deprecated-hid-flasher from client to tools
* Makefiles
  * treat deps in armsrc/ as in client/
  * client: stop on warning (-Werror), same as for armsrc/

Tested on:

* all standalone modes
* Linux
2019-08-11 21:42:01 +02:00

50 lines
1.6 KiB
C

#ifndef OPTIMIZED_CIPHER_H
#define OPTIMIZED_CIPHER_H
#include "common.h"
/**
* 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;
/** The reader MAC is MAC(key, CC * NR )
**/
void opt_doReaderMAC(uint8_t *cc_nr_p, uint8_t *div_key_p, uint8_t mac[4]);
/**
* The tag MAC is MAC(key, CC * NR * 32x0))
*/
void opt_doTagMAC(uint8_t *cc_p, const uint8_t *div_key_p, uint8_t mac[4]);
/**
* The tag MAC can be divided (both can, but no point in dividing the reader mac) into
* two functions, since the first 8 bytes are known, we can pre-calculate the state
* reached after feeding CC to the cipher.
* @param cc_p
* @param div_key_p
* @return the cipher state
*/
State opt_doTagMAC_1(uint8_t *cc_p, const uint8_t *div_key_p);
/**
* The second part of the tag MAC calculation, since the CC is already calculated into the state,
* this function is fed only the NR, and internally feeds the remaining 32 0-bits to generate the tag
* MAC response.
* @param _init - precalculated cipher state
* @param nr - the reader challenge
* @param mac - where to store the MAC
* @param div_key_p - the key to use
*/
void opt_doTagMAC_2(State _init, uint8_t *nr, uint8_t mac[4], const uint8_t *div_key_p);
#endif // OPTIMIZED_CIPHER_H