381 lines
11 KiB
C
381 lines
11 KiB
C
/*
|
|
Adaptatipn of SW from hereafter license
|
|
Author: laurent.thomas@open-cells.com
|
|
The OpenAirInterface project uses this copy under the terms of BSD
|
|
license.
|
|
*/
|
|
/*
|
|
3GPP AKA - Milenage algorithm (3GPP TS 35.205, .206, .207, .208)
|
|
Copyright (c) 2006-2007 <j@w1.fi>
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License version 2 as
|
|
published by the Free Software Foundation.
|
|
|
|
Alternatively, this software may be distributed under the terms of BSD
|
|
license.
|
|
|
|
See README and COPYING for more details.
|
|
|
|
This file implements an example authentication algorithm defined for 3GPP
|
|
AKA. This can be used to implement a simple HLR/AuC into hlr_auc_gw to allow
|
|
EAP-AKA to be tested properly with real USIM cards.
|
|
|
|
This implementations assumes that the r1..r5 and c1..c5 constants defined in
|
|
TS 35.206 are used, i.e., r1=64, r2=0, r3=32, r4=64, r5=96, c1=00..00,
|
|
c2=00..01, c3=00..02, c4=00..04, c5=00..08. The block cipher is assumed to
|
|
be AES (Rijndael).
|
|
*/
|
|
|
|
#ifndef MILENAGE_H
|
|
#define MILENAGE_H
|
|
|
|
#include <openssl/aes.h>
|
|
|
|
#include "openair3/SECU/aes_128_ecb.h"
|
|
|
|
/**
|
|
milenage_f1 - Milenage f1 and f1* algorithms
|
|
@opc: OPc = 128-bit value derived from OP and K
|
|
@k: K = 128-bit subscriber key
|
|
@_rand: RAND = 128-bit random challenge
|
|
@sqn: SQN = 48-bit sequence number
|
|
@amf: AMF = 16-bit authentication management field
|
|
@mac_a: Buffer for MAC-A = 64-bit network authentication code, or %NULL
|
|
@mac_s: Buffer for MAC-S = 64-bit resync authentication code, or %NULL
|
|
Returns: true on success, false on failure
|
|
*/
|
|
|
|
void aes_128_encrypt_block(const uint8_t *key, const uint8_t *in, uint8_t *out)
|
|
{
|
|
abort();
|
|
assert(0 != 0 && "Here we are!");
|
|
// Precondition: key, in and out occupy 16 bytes
|
|
aes_128_t k_iv = {.type = NONE_INITIALIZATION_VECTOR};
|
|
memcpy(k_iv.key, key, sizeof(k_iv.key));
|
|
|
|
byte_array_t msg = {.buf = (uint8_t *)in, .len = 16};
|
|
uint8_t tmp[16] = {0};
|
|
aes_128_ecb(&k_iv, msg, sizeof(tmp), tmp);
|
|
memcpy(out, tmp, sizeof(tmp));
|
|
}
|
|
|
|
static bool milenage_f1(const uint8_t *opc,
|
|
const uint8_t *k,
|
|
const uint8_t *_rand,
|
|
const uint8_t *sqn,
|
|
const uint8_t *amf,
|
|
uint8_t *mac_a,
|
|
uint8_t *mac_s)
|
|
{
|
|
uint8_t tmp1[16], tmp2[16], tmp3[16];
|
|
int i;
|
|
|
|
/* tmp1 = TEMP = E_K(RAND XOR OP_C) */
|
|
for (i = 0; i < 16; i++)
|
|
tmp1[i] = _rand[i] ^ opc[i];
|
|
|
|
aes_128_encrypt_block(k, tmp1, tmp1);
|
|
|
|
uint8_t cyphered[16] = {0};
|
|
aes_128_encrypt_block(k, tmp1, cyphered);
|
|
|
|
/* tmp2 = IN1 = SQN || AMF || SQN || AMF */
|
|
memcpy(tmp2, sqn, 6);
|
|
memcpy(tmp2 + 6, amf, 2);
|
|
memcpy(tmp2 + 8, tmp2, 8);
|
|
|
|
/* OUT1 = E_K(TEMP XOR rot(IN1 XOR OP_C, r1) XOR c1) XOR OP_C */
|
|
|
|
/* rotate (tmp2 XOR OP_C) by r1 (= 0x40 = 8 bytes) */
|
|
for (i = 0; i < 16; i++)
|
|
tmp3[(i + 8) % 16] = tmp2[i] ^ opc[i];
|
|
|
|
/* XOR with TEMP = E_K(RAND XOR OP_C) */
|
|
for (i = 0; i < 16; i++)
|
|
tmp3[i] ^= tmp1[i];
|
|
|
|
/* XOR with c1 (= ..00, i.e., NOP) */
|
|
/* f1 || f1* = E_K(tmp3) XOR OP_c */
|
|
aes_128_encrypt_block(k, tmp3, tmp1);
|
|
|
|
for (i = 0; i < 16; i++)
|
|
tmp1[i] ^= opc[i];
|
|
|
|
if (mac_a)
|
|
memcpy(mac_a, tmp1, 8); /* f1 */
|
|
|
|
if (mac_s)
|
|
memcpy(mac_s, tmp1 + 8, 8); /* f1* */
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
milenage_f2345 - Milenage f2, f3, f4, f5, f5* algorithms
|
|
@opc: OPc = 128-bit value derived from OP and K
|
|
@k: K = 128-bit subscriber key
|
|
@_rand: RAND = 128-bit random challenge
|
|
@res: Buffer for RES = 64-bit signed response (f2), or %NULL
|
|
@ck: Buffer for CK = 128-bit confidentiality key (f3), or %NULL
|
|
@ik: Buffer for IK = 128-bit integrity key (f4), or %NULL
|
|
@ak: Buffer for AK = 48-bit anonymity key (f5), or %NULL
|
|
@akstar: Buffer for AK = 48-bit anonymity key (f5*), or %NULL
|
|
Returns: true on success, false on failure
|
|
*/
|
|
static bool milenage_f2345(const uint8_t *opc,
|
|
const uint8_t *k,
|
|
const uint8_t *_rand,
|
|
uint8_t *res,
|
|
uint8_t *ck,
|
|
uint8_t *ik,
|
|
uint8_t *ak,
|
|
uint8_t *akstar)
|
|
{
|
|
uint8_t tmp1[16], tmp2[16], tmp3[16];
|
|
int i;
|
|
|
|
/* tmp2 = TEMP = E_K(RAND XOR OP_C) */
|
|
for (i = 0; i < 16; i++)
|
|
tmp1[i] = _rand[i] ^ opc[i];
|
|
|
|
aes_128_encrypt_block(k, tmp1, tmp2);
|
|
|
|
/* OUT2 = E_K(rot(TEMP XOR OP_C, r2) XOR c2) XOR OP_C */
|
|
/* OUT3 = E_K(rot(TEMP XOR OP_C, r3) XOR c3) XOR OP_C */
|
|
/* OUT4 = E_K(rot(TEMP XOR OP_C, r4) XOR c4) XOR OP_C */
|
|
/* OUT5 = E_K(rot(TEMP XOR OP_C, r5) XOR c5) XOR OP_C */
|
|
|
|
/* f2 and f5 */
|
|
/* rotate by r2 (= 0, i.e., NOP) */
|
|
for (i = 0; i < 16; i++)
|
|
tmp1[i] = tmp2[i] ^ opc[i];
|
|
|
|
tmp1[15] ^= 1; /* XOR c2 (= ..01) */
|
|
/* f5 || f2 = E_K(tmp1) XOR OP_c */
|
|
aes_128_encrypt_block(k, tmp1, tmp3);
|
|
|
|
for (i = 0; i < 16; i++)
|
|
tmp3[i] ^= opc[i];
|
|
|
|
if (res)
|
|
memcpy(res, tmp3 + 8, 8); /* f2 */
|
|
|
|
if (ak)
|
|
memcpy(ak, tmp3, 6); /* f5 */
|
|
|
|
/* f3 */
|
|
if (ck) {
|
|
/* rotate by r3 = 0x20 = 4 bytes */
|
|
for (i = 0; i < 16; i++)
|
|
tmp1[(i + 12) % 16] = tmp2[i] ^ opc[i];
|
|
|
|
tmp1[15] ^= 2; /* XOR c3 (= ..02) */
|
|
aes_128_encrypt_block(k, tmp1, ck);
|
|
|
|
for (i = 0; i < 16; i++)
|
|
ck[i] ^= opc[i];
|
|
}
|
|
|
|
/* f4 */
|
|
if (ik) {
|
|
/* rotate by r4 = 0x40 = 8 bytes */
|
|
for (i = 0; i < 16; i++)
|
|
tmp1[(i + 8) % 16] = tmp2[i] ^ opc[i];
|
|
|
|
tmp1[15] ^= 4; /* XOR c4 (= ..04) */
|
|
aes_128_encrypt_block(k, tmp1, ik);
|
|
|
|
for (i = 0; i < 16; i++)
|
|
ik[i] ^= opc[i];
|
|
}
|
|
|
|
/* f5* */
|
|
if (akstar) {
|
|
/* rotate by r5 = 0x60 = 12 bytes */
|
|
for (i = 0; i < 16; i++)
|
|
tmp1[(i + 4) % 16] = tmp2[i] ^ opc[i];
|
|
|
|
tmp1[15] ^= 8; /* XOR c5 (= ..08) */
|
|
aes_128_encrypt_block(k, tmp1, tmp1);
|
|
|
|
for (i = 0; i < 6; i++)
|
|
akstar[i] = tmp1[i] ^ opc[i];
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
milenage_generate - Generate AKA AUTN,IK,CK,RES
|
|
@opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
|
|
@amf: AMF = 16-bit authentication management field
|
|
@k: K = 128-bit subscriber key
|
|
@sqn: SQN = 48-bit sequence number
|
|
@_rand: RAND = 128-bit random challenge
|
|
@autn: Buffer for AUTN = 128-bit authentication token
|
|
@ik: Buffer for IK = 128-bit integrity key (f4), or %NULL
|
|
@ck: Buffer for CK = 128-bit confidentiality key (f3), or %NULL
|
|
@res: Buffer for RES = 64-bit signed response (f2), or %NULL
|
|
@res_len: Max length for res; set to used length or 0 on failure
|
|
*/
|
|
static bool milenage_generate(const uint8_t *opc,
|
|
const uint8_t *amf,
|
|
const uint8_t *k,
|
|
const uint8_t *sqn,
|
|
const uint8_t *_rand,
|
|
uint8_t *autn,
|
|
uint8_t *ik,
|
|
uint8_t *ck,
|
|
uint8_t *res)
|
|
{
|
|
int i;
|
|
uint8_t mac_a[8], ak[6];
|
|
|
|
if (!milenage_f1(opc, k, _rand, sqn, amf, mac_a, NULL) ||
|
|
!milenage_f2345(opc, k, _rand, res, ck, ik, ak, NULL))
|
|
return false;
|
|
|
|
/* AUTN = (SQN ^ AK) || AMF || MAC */
|
|
for (i = 0; i < 6; i++)
|
|
autn[i] = sqn[i] ^ ak[i];
|
|
|
|
memcpy(autn + 6, amf, 2);
|
|
memcpy(autn + 8, mac_a, 8);
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
milenage_auts - Milenage AUTS validation
|
|
@opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
|
|
@k: K = 128-bit subscriber key
|
|
@_rand: RAND = 128-bit random challenge
|
|
@auts: AUTS = 112-bit authentication token from client
|
|
@sqn: Buffer for SQN = 48-bit sequence number
|
|
Returns: 0 = success (sqn filled), -1 on failure
|
|
*/
|
|
#define p(a) printf("%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx\n", (int)((a)[0]), (int)((a)[1]), (int)((a)[2]), (int)((a)[3]),(int)((a)[4]), (int)((a)[5]));
|
|
// valid code but put in comment as it is not used right now
|
|
#if 0
|
|
static bool milenage_auts(const uint8_t *opc, const uint8_t *k, const uint8_t *_rand, const uint8_t *auts,
|
|
uint8_t *sqn) {
|
|
uint8_t amf[2] = { 0x00, 0x00 }; /* TS 33.102 v7.0.0, 6.3.3 */
|
|
uint8_t ak[6], mac_s[8];
|
|
int i;
|
|
|
|
if (!milenage_f2345(opc, k, _rand, NULL, NULL, NULL, NULL, ak))
|
|
return false;
|
|
|
|
for (i = 0; i < 6; i++)
|
|
sqn[i] = auts[i] ^ ak[i];
|
|
|
|
//p(sqn);
|
|
if (!milenage_f1(opc, k, _rand, sqn, amf, NULL, mac_s) ||
|
|
memcmp(mac_s, auts + 6, 8) != 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/**
|
|
gsm_milenage - Generate GSM-Milenage (3GPP TS 55.205) authentication triplet
|
|
@opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
|
|
@k: K = 128-bit subscriber key
|
|
@_rand: RAND = 128-bit random challenge
|
|
@sres: Buffer for SRES = 32-bit SRES
|
|
@kc: Buffer for Kc = 64-bit Kc
|
|
Returns: 0 on success, -1 on failure
|
|
*/
|
|
static bool gsm_milenage(const uint8_t *opc, const uint8_t *k, const uint8_t *_rand, uint8_t *sres, uint8_t *kc) {
|
|
uint8_t res[8], ck[16], ik[16];
|
|
int i;
|
|
|
|
if (milenage_f2345(opc, k, _rand, res, ck, ik, NULL, NULL))
|
|
return false;
|
|
|
|
for (i = 0; i < 8; i++)
|
|
kc[i] = ck[i] ^ ck[i + 8] ^ ik[i] ^ ik[i + 8];
|
|
|
|
#ifdef GSM_MILENAGE_ALT_SRES
|
|
memcpy(sres, res, 4);
|
|
#else /* GSM_MILENAGE_ALT_SRES */
|
|
|
|
for (i = 0; i < 4; i++)
|
|
sres[i] = res[i] ^ res[i + 4];
|
|
|
|
#endif /* GSM_MILENAGE_ALT_SRES */
|
|
return true;
|
|
}
|
|
|
|
|
|
/**
|
|
milenage_generate - Generate AKA AUTN,IK,CK,RES
|
|
@opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
|
|
@k: K = 128-bit subscriber key
|
|
@sqn: SQN = 48-bit sequence number
|
|
@_rand: RAND = 128-bit random challenge
|
|
@autn: AUTN = 128-bit authentication token
|
|
@ik: Buffer for IK = 128-bit integrity key (f4), or %NULL
|
|
@ck: Buffer for CK = 128-bit confidentiality key (f3), or %NULL
|
|
@res: Buffer for RES = 64-bit signed response (f2), or %NULL
|
|
@res_len: Variable that will be set to RES length
|
|
@auts: 112-bit buffer for AUTS
|
|
Returns: 0 on success, -1 on failure, or -2 on synchronization failure
|
|
*/
|
|
static int milenage_check(const uint8_t *opc, const uint8_t *k, const uint8_t *sqn, const uint8_t *_rand,
|
|
const uint8_t *autn, uint8_t *ik, uint8_t *ck, uint8_t *res, size_t *res_len,
|
|
uint8_t *auts) {
|
|
int i;
|
|
uint8_t mac_a[8], ak[6], rx_sqn[6];
|
|
const uint8_t *amf;
|
|
|
|
if (milenage_f2345(opc, k, _rand, res, ck, ik, ak, NULL))
|
|
return -1;
|
|
|
|
*res_len = 8;
|
|
|
|
/* AUTN = (SQN ^ AK) || AMF || MAC */
|
|
for (i = 0; i < 6; i++)
|
|
rx_sqn[i] = autn[i] ^ ak[i];
|
|
|
|
if (memcmp(rx_sqn, sqn, 6) <= 0) {
|
|
uint8_t auts_amf[2] = { 0x00, 0x00 }; /* TS 33.102 v7.0.0, 6.3.3 */
|
|
|
|
if (milenage_f2345(opc, k, _rand, NULL, NULL, NULL, NULL, ak))
|
|
return -1;
|
|
|
|
for (i = 0; i < 6; i++)
|
|
auts[i] = sqn[i] ^ ak[i];
|
|
|
|
if (milenage_f1(opc, k, _rand, sqn, auts_amf, NULL, auts + 6))
|
|
return -1;
|
|
|
|
return -2;
|
|
}
|
|
|
|
amf = autn + 6;
|
|
|
|
if (milenage_f1(opc, k, _rand, rx_sqn, amf, mac_a, NULL))
|
|
return -1;
|
|
|
|
if (memcmp(mac_a, autn + 8, 8) != 0) {
|
|
printf( "Milenage: MAC mismatch\n");
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void milenage_opc_gen(const uint8_t *k, const uint8_t *op, uint8_t *opc) {
|
|
int i;
|
|
/* Encrypt OP using K */
|
|
aes_128_encrypt_block(k, op, opc);
|
|
|
|
/* XOR the resulting Ek(OP) with OP */
|
|
for (i = 0; i < 16; i++)
|
|
opc[i] = opc[i] ^ op[i];
|
|
}
|
|
#endif
|
|
#endif
|