libosmocore/include/osmocom/crypt/gprs_cipher.h

55 lines
1.5 KiB
C

#ifndef _GPRS_CIPHER_H
#define _GPRS_CIPHER_H
#include <osmocom/core/linuxlist.h>
#define GSM0464_CIPH_MAX_BLOCK 1523
enum gprs_ciph_algo {
GPRS_ALGO_GEA0,
GPRS_ALGO_GEA1,
GPRS_ALGO_GEA2,
GPRS_ALGO_GEA3,
_GPRS_ALGO_NUM
};
enum gprs_cipher_direction {
GPRS_CIPH_MS2SGSN,
GPRS_CIPH_SGSN2MS,
};
/* An implementation of a GPRS cipher */
struct gprs_cipher_impl {
struct llist_head list;
enum gprs_ciph_algo algo;
const char *name;
unsigned int priority;
/* As specified in 04.64 Annex A. Uses Kc, IV and direction
* to generate the 1523 bytes cipher stream that need to be
* XORed wit the plaintext for encrypt / ciphertext for decrypt */
int (*run)(uint8_t *out, uint16_t len, uint64_t kc, uint32_t iv,
enum gprs_cipher_direction direction);
};
/* register a cipher with the core (from a plugin) */
int gprs_cipher_register(struct gprs_cipher_impl *ciph);
/* load all available GPRS cipher plugins */
int gprs_cipher_load(const char *path);
/* function to be called by core code */
int gprs_cipher_run(uint8_t *out, uint16_t len, enum gprs_ciph_algo algo,
uint64_t kc, uint32_t iv, enum gprs_cipher_direction dir);
/* Do we have an implementation for this cipher? */
int gprs_cipher_supported(enum gprs_ciph_algo algo);
/* GSM TS 04.64 / Section A.2.1 : Generation of 'input' */
uint32_t gprs_cipher_gen_input_ui(uint32_t iov_ui, uint8_t sapi, uint32_t lfn, uint32_t oc);
/* GSM TS 04.64 / Section A.2.1 : Generation of 'input' */
uint32_t gprs_cipher_gen_input_i(uint32_t iov_i, uint32_t lfn, uint32_t oc);
#endif /* _GPRS_CIPHER_H */