1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
/*! \file gprs_cipher.h */
#pragma once
#include <osmocom/core/linuxlist.h>
#include <osmocom/core/utils.h>
#include <stdint.h>
#define GSM0464_CIPH_MAX_BLOCK 1523
/* 3GPP TS 24.008 § 10.5.5.3 */
enum gprs_ciph_algo {
GPRS_ALGO_GEA0 = 0,
GPRS_ALGO_GEA1 = 1,
GPRS_ALGO_GEA2 = 2,
GPRS_ALGO_GEA3 = 3,
GPRS_ALGO_GEA4 = 4,
_GPRS_ALGO_NUM
};
/* 3GPP TS 04.64 Table A.1: */
enum gprs_cipher_direction {
GPRS_CIPH_MS2SGSN = 0,
GPRS_CIPH_SGSN2MS = 1,
};
extern const struct value_string gprs_cipher_names[];
/* 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, uint8_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,
uint8_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);
/* Return key length for supported cipher, in bytes */
unsigned gprs_cipher_key_length(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);
|
