2 * 3GPP AKA - Milenage algorithm (3GPP TS 35.205, .206, .207, .208)
3 * Copyright (c) 2006-2007 <j@w1.fi>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * Alternatively, this software may be distributed under the terms of BSD
12 * See README and COPYING for more details.
14 * This file implements an example authentication algorithm defined for 3GPP
15 * AKA. This can be used to implement a simple HLR/AuC into hlr_auc_gw to allow
16 * EAP-AKA to be tested properly with real USIM cards.
18 * This implementations assumes that the r1..r5 and c1..c5 constants defined in
19 * TS 35.206 are used, i.e., r1=64, r2=0, r3=32, r4=64, r5=96, c1=00..00,
20 * c2=00..01, c3=00..02, c4=00..04, c5=00..08. The block cipher is assumed to
27 #include "crypto/aes_wrap.h"
32 * milenage_f1 - Milenage f1 and f1* algorithms
33 * @opc: OPc = 128-bit value derived from OP and K
34 * @k: K = 128-bit subscriber key
35 * @_rand: RAND = 128-bit random challenge
36 * @sqn: SQN = 48-bit sequence number
37 * @amf: AMF = 16-bit authentication management field
38 * @mac_a: Buffer for MAC-A = 64-bit network authentication code, or %NULL
39 * @mac_s: Buffer for MAC-S = 64-bit resync authentication code, or %NULL
40 * Returns: 0 on success, -1 on failure
42 int milenage_f1(const u8 *opc, const u8 *k, const u8 *_rand,
43 const u8 *sqn, const u8 *amf, u8 *mac_a, u8 *mac_s)
45 u8 tmp1[16], tmp2[16], tmp3[16];
48 /* tmp1 = TEMP = E_K(RAND XOR OP_C) */
49 for (i = 0; i < 16; i++)
50 tmp1[i] = _rand[i] ^ opc[i];
51 if (aes_128_encrypt_block(k, tmp1, tmp1))
54 /* tmp2 = IN1 = SQN || AMF || SQN || AMF */
55 os_memcpy(tmp2, sqn, 6);
56 os_memcpy(tmp2 + 6, amf, 2);
57 os_memcpy(tmp2 + 8, tmp2, 8);
59 /* OUT1 = E_K(TEMP XOR rot(IN1 XOR OP_C, r1) XOR c1) XOR OP_C */
61 /* rotate (tmp2 XOR OP_C) by r1 (= 0x40 = 8 bytes) */
62 for (i = 0; i < 16; i++)
63 tmp3[(i + 8) % 16] = tmp2[i] ^ opc[i];
64 /* XOR with TEMP = E_K(RAND XOR OP_C) */
65 for (i = 0; i < 16; i++)
67 /* XOR with c1 (= ..00, i.e., NOP) */
69 /* f1 || f1* = E_K(tmp3) XOR OP_c */
70 if (aes_128_encrypt_block(k, tmp3, tmp1))
72 for (i = 0; i < 16; i++)
75 os_memcpy(mac_a, tmp1, 8); /* f1 */
77 os_memcpy(mac_s, tmp1 + 8, 8); /* f1* */
83 * milenage_f2345 - Milenage f2, f3, f4, f5, f5* algorithms
84 * @opc: OPc = 128-bit value derived from OP and K
85 * @k: K = 128-bit subscriber key
86 * @_rand: RAND = 128-bit random challenge
87 * @res: Buffer for RES = 64-bit signed response (f2), or %NULL
88 * @ck: Buffer for CK = 128-bit confidentiality key (f3), or %NULL
89 * @ik: Buffer for IK = 128-bit integrity key (f4), or %NULL
90 * @ak: Buffer for AK = 48-bit anonymity key (f5), or %NULL
91 * @akstar: Buffer for AK = 48-bit anonymity key (f5*), or %NULL
92 * Returns: 0 on success, -1 on failure
94 int milenage_f2345(const u8 *opc, const u8 *k, const u8 *_rand,
95 u8 *res, u8 *ck, u8 *ik, u8 *ak, u8 *akstar)
97 u8 tmp1[16], tmp2[16], tmp3[16];
100 /* tmp2 = TEMP = E_K(RAND XOR OP_C) */
101 for (i = 0; i < 16; i++)
102 tmp1[i] = _rand[i] ^ opc[i];
103 if (aes_128_encrypt_block(k, tmp1, tmp2))
106 /* OUT2 = E_K(rot(TEMP XOR OP_C, r2) XOR c2) XOR OP_C */
107 /* OUT3 = E_K(rot(TEMP XOR OP_C, r3) XOR c3) XOR OP_C */
108 /* OUT4 = E_K(rot(TEMP XOR OP_C, r4) XOR c4) XOR OP_C */
109 /* OUT5 = E_K(rot(TEMP XOR OP_C, r5) XOR c5) XOR OP_C */
112 /* rotate by r2 (= 0, i.e., NOP) */
113 for (i = 0; i < 16; i++)
114 tmp1[i] = tmp2[i] ^ opc[i];
115 tmp1[15] ^= 1; /* XOR c2 (= ..01) */
116 /* f5 || f2 = E_K(tmp1) XOR OP_c */
117 if (aes_128_encrypt_block(k, tmp1, tmp3))
119 for (i = 0; i < 16; i++)
122 os_memcpy(res, tmp3 + 8, 8); /* f2 */
124 os_memcpy(ak, tmp3, 6); /* f5 */
128 /* rotate by r3 = 0x20 = 4 bytes */
129 for (i = 0; i < 16; i++)
130 tmp1[(i + 12) % 16] = tmp2[i] ^ opc[i];
131 tmp1[15] ^= 2; /* XOR c3 (= ..02) */
132 if (aes_128_encrypt_block(k, tmp1, ck))
134 for (i = 0; i < 16; i++)
140 /* rotate by r4 = 0x40 = 8 bytes */
141 for (i = 0; i < 16; i++)
142 tmp1[(i + 8) % 16] = tmp2[i] ^ opc[i];
143 tmp1[15] ^= 4; /* XOR c4 (= ..04) */
144 if (aes_128_encrypt_block(k, tmp1, ik))
146 for (i = 0; i < 16; i++)
152 /* rotate by r5 = 0x60 = 12 bytes */
153 for (i = 0; i < 16; i++)
154 tmp1[(i + 4) % 16] = tmp2[i] ^ opc[i];
155 tmp1[15] ^= 8; /* XOR c5 (= ..08) */
156 if (aes_128_encrypt_block(k, tmp1, tmp1))
158 for (i = 0; i < 6; i++)
159 akstar[i] = tmp1[i] ^ opc[i];
167 * milenage_generate - Generate AKA AUTN,IK,CK,RES
168 * @opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
169 * @amf: AMF = 16-bit authentication management field
170 * @k: K = 128-bit subscriber key
171 * @sqn: SQN = 48-bit sequence number
172 * @_rand: RAND = 128-bit random challenge
173 * @autn: Buffer for AUTN = 128-bit authentication token
174 * @ik: Buffer for IK = 128-bit integrity key (f4), or %NULL
175 * @ck: Buffer for CK = 128-bit confidentiality key (f3), or %NULL
176 * @res: Buffer for RES = 64-bit signed response (f2), or %NULL
177 * @res_len: Max length for res; set to used length or 0 on failure
179 void milenage_generate(const u8 *opc, const u8 *amf, const u8 *k,
180 const u8 *sqn, const u8 *_rand, u8 *autn, u8 *ik,
181 u8 *ck, u8 *res, size_t *res_len)
190 if (milenage_f1(opc, k, _rand, sqn, amf, mac_a, NULL) ||
191 milenage_f2345(opc, k, _rand, res, ck, ik, ak, NULL)) {
197 /* AUTN = (SQN ^ AK) || AMF || MAC */
198 for (i = 0; i < 6; i++)
199 autn[i] = sqn[i] ^ ak[i];
200 os_memcpy(autn + 6, amf, 2);
201 os_memcpy(autn + 8, mac_a, 8);
206 * milenage_auts - Milenage AUTS validation
207 * @opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
208 * @k: K = 128-bit subscriber key
209 * @_rand: RAND = 128-bit random challenge
210 * @auts: AUTS = 112-bit authentication token from client
211 * @sqn: Buffer for SQN = 48-bit sequence number
212 * Returns: 0 = success (sqn filled), -1 on failure
214 int milenage_auts(const u8 *opc, const u8 *k, const u8 *_rand, const u8 *auts,
217 u8 amf[2] = { 0x00, 0x00 }; /* TS 33.102 v7.0.0, 6.3.3 */
221 if (milenage_f2345(opc, k, _rand, NULL, NULL, NULL, NULL, ak))
223 for (i = 0; i < 6; i++)
224 sqn[i] = auts[i] ^ ak[i];
225 if (milenage_f1(opc, k, _rand, sqn, amf, NULL, mac_s) ||
226 memcmp(mac_s, auts + 6, 8) != 0)
233 * gsm_milenage - Generate GSM-Milenage (3GPP TS 55.205) authentication triplet
234 * @opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
235 * @k: K = 128-bit subscriber key
236 * @_rand: RAND = 128-bit random challenge
237 * @sres: Buffer for SRES = 32-bit SRES
238 * @kc: Buffer for Kc = 64-bit Kc
239 * Returns: 0 on success, -1 on failure
241 int gsm_milenage(const u8 *opc, const u8 *k, const u8 *_rand, u8 *sres, u8 *kc)
243 u8 res[8], ck[16], ik[16];
246 if (milenage_f2345(opc, k, _rand, res, ck, ik, NULL, NULL))
249 for (i = 0; i < 8; i++)
250 kc[i] = ck[i] ^ ck[i + 8] ^ ik[i] ^ ik[i + 8];
252 #ifdef GSM_MILENAGE_ALT_SRES
253 os_memcpy(sres, res, 4);
254 #else /* GSM_MILENAGE_ALT_SRES */
255 for (i = 0; i < 4; i++)
256 sres[i] = res[i] ^ res[i + 4];
257 #endif /* GSM_MILENAGE_ALT_SRES */
263 * milenage_generate - Generate AKA AUTN,IK,CK,RES
264 * @opc: OPc = 128-bit operator variant algorithm configuration field (encr.)
265 * @k: K = 128-bit subscriber key
266 * @sqn: SQN = 48-bit sequence number
267 * @_rand: RAND = 128-bit random challenge
268 * @autn: AUTN = 128-bit authentication token
269 * @ik: Buffer for IK = 128-bit integrity key (f4), or %NULL
270 * @ck: Buffer for CK = 128-bit confidentiality key (f3), or %NULL
271 * @res: Buffer for RES = 64-bit signed response (f2), or %NULL
272 * @res_len: Variable that will be set to RES length
273 * @auts: 112-bit buffer for AUTS
274 * Returns: 0 on success, -1 on failure, or -2 on synchronization failure
276 int milenage_check(const u8 *opc, const u8 *k, const u8 *sqn, const u8 *_rand,
277 const u8 *autn, u8 *ik, u8 *ck, u8 *res, size_t *res_len,
281 u8 mac_a[8], ak[6], rx_sqn[6];
284 wpa_hexdump(MSG_DEBUG, "Milenage: AUTN", autn, 16);
285 wpa_hexdump(MSG_DEBUG, "Milenage: RAND", _rand, 16);
287 if (milenage_f2345(opc, k, _rand, res, ck, ik, ak, NULL))
291 wpa_hexdump_key(MSG_DEBUG, "Milenage: RES", res, *res_len);
292 wpa_hexdump_key(MSG_DEBUG, "Milenage: CK", ck, 16);
293 wpa_hexdump_key(MSG_DEBUG, "Milenage: IK", ik, 16);
294 wpa_hexdump_key(MSG_DEBUG, "Milenage: AK", ak, 6);
296 /* AUTN = (SQN ^ AK) || AMF || MAC */
297 for (i = 0; i < 6; i++)
298 rx_sqn[i] = autn[i] ^ ak[i];
299 wpa_hexdump(MSG_DEBUG, "Milenage: SQN", rx_sqn, 6);
301 if (os_memcmp(rx_sqn, sqn, 6) <= 0) {
302 u8 auts_amf[2] = { 0x00, 0x00 }; /* TS 33.102 v7.0.0, 6.3.3 */
303 if (milenage_f2345(opc, k, _rand, NULL, NULL, NULL, NULL, ak))
305 wpa_hexdump_key(MSG_DEBUG, "Milenage: AK*", ak, 6);
306 for (i = 0; i < 6; i++)
307 auts[i] = sqn[i] ^ ak[i];
308 if (milenage_f1(opc, k, _rand, sqn, auts_amf, NULL, auts + 6))
310 wpa_hexdump(MSG_DEBUG, "Milenage: AUTS", auts, 14);
315 wpa_hexdump(MSG_DEBUG, "Milenage: AMF", amf, 2);
316 if (milenage_f1(opc, k, _rand, rx_sqn, amf, mac_a, NULL))
319 wpa_hexdump(MSG_DEBUG, "Milenage: MAC_A", mac_a, 8);
321 if (os_memcmp(mac_a, autn + 8, 8) != 0) {
322 wpa_printf(MSG_DEBUG, "Milenage: MAC mismatch");
323 wpa_hexdump(MSG_DEBUG, "Milenage: Received MAC_A",