1 /*
2 * Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
3 *
4 * Licensed under the Apache License, Version 2.0 (the License); you may
5 * not use this file except in compliance with the License.
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 */
9
10
11 #include <stdlib.h>
12 #include <string.h>
13 #include <gmssl/zuc.h>
14 #include <gmssl/mem.h>
15 #include <gmssl/endian.h>
16
17
18 static const ZUC_UINT15 KD[16] = {
19 0x44D7,0x26BC,0x626B,0x135E,0x5789,0x35E2,0x7135,0x09AF,
20 0x4D78,0x2F13,0x6BC4,0x1AF1,0x5E26,0x3C4D,0x789A,0x47AC,
21 };
22
23 static const uint8_t S0[256] = {
24 0x3e,0x72,0x5b,0x47,0xca,0xe0,0x00,0x33,0x04,0xd1,0x54,0x98,0x09,0xb9,0x6d,0xcb,
25 0x7b,0x1b,0xf9,0x32,0xaf,0x9d,0x6a,0xa5,0xb8,0x2d,0xfc,0x1d,0x08,0x53,0x03,0x90,
26 0x4d,0x4e,0x84,0x99,0xe4,0xce,0xd9,0x91,0xdd,0xb6,0x85,0x48,0x8b,0x29,0x6e,0xac,
27 0xcd,0xc1,0xf8,0x1e,0x73,0x43,0x69,0xc6,0xb5,0xbd,0xfd,0x39,0x63,0x20,0xd4,0x38,
28 0x76,0x7d,0xb2,0xa7,0xcf,0xed,0x57,0xc5,0xf3,0x2c,0xbb,0x14,0x21,0x06,0x55,0x9b,
29 0xe3,0xef,0x5e,0x31,0x4f,0x7f,0x5a,0xa4,0x0d,0x82,0x51,0x49,0x5f,0xba,0x58,0x1c,
30 0x4a,0x16,0xd5,0x17,0xa8,0x92,0x24,0x1f,0x8c,0xff,0xd8,0xae,0x2e,0x01,0xd3,0xad,
31 0x3b,0x4b,0xda,0x46,0xeb,0xc9,0xde,0x9a,0x8f,0x87,0xd7,0x3a,0x80,0x6f,0x2f,0xc8,
32 0xb1,0xb4,0x37,0xf7,0x0a,0x22,0x13,0x28,0x7c,0xcc,0x3c,0x89,0xc7,0xc3,0x96,0x56,
33 0x07,0xbf,0x7e,0xf0,0x0b,0x2b,0x97,0x52,0x35,0x41,0x79,0x61,0xa6,0x4c,0x10,0xfe,
34 0xbc,0x26,0x95,0x88,0x8a,0xb0,0xa3,0xfb,0xc0,0x18,0x94,0xf2,0xe1,0xe5,0xe9,0x5d,
35 0xd0,0xdc,0x11,0x66,0x64,0x5c,0xec,0x59,0x42,0x75,0x12,0xf5,0x74,0x9c,0xaa,0x23,
36 0x0e,0x86,0xab,0xbe,0x2a,0x02,0xe7,0x67,0xe6,0x44,0xa2,0x6c,0xc2,0x93,0x9f,0xf1,
37 0xf6,0xfa,0x36,0xd2,0x50,0x68,0x9e,0x62,0x71,0x15,0x3d,0xd6,0x40,0xc4,0xe2,0x0f,
38 0x8e,0x83,0x77,0x6b,0x25,0x05,0x3f,0x0c,0x30,0xea,0x70,0xb7,0xa1,0xe8,0xa9,0x65,
39 0x8d,0x27,0x1a,0xdb,0x81,0xb3,0xa0,0xf4,0x45,0x7a,0x19,0xdf,0xee,0x78,0x34,0x60,
40 };
41
42 static const uint8_t S1[256] = {
43 0x55,0xc2,0x63,0x71,0x3b,0xc8,0x47,0x86,0x9f,0x3c,0xda,0x5b,0x29,0xaa,0xfd,0x77,
44 0x8c,0xc5,0x94,0x0c,0xa6,0x1a,0x13,0x00,0xe3,0xa8,0x16,0x72,0x40,0xf9,0xf8,0x42,
45 0x44,0x26,0x68,0x96,0x81,0xd9,0x45,0x3e,0x10,0x76,0xc6,0xa7,0x8b,0x39,0x43,0xe1,
46 0x3a,0xb5,0x56,0x2a,0xc0,0x6d,0xb3,0x05,0x22,0x66,0xbf,0xdc,0x0b,0xfa,0x62,0x48,
47 0xdd,0x20,0x11,0x06,0x36,0xc9,0xc1,0xcf,0xf6,0x27,0x52,0xbb,0x69,0xf5,0xd4,0x87,
48 0x7f,0x84,0x4c,0xd2,0x9c,0x57,0xa4,0xbc,0x4f,0x9a,0xdf,0xfe,0xd6,0x8d,0x7a,0xeb,
49 0x2b,0x53,0xd8,0x5c,0xa1,0x14,0x17,0xfb,0x23,0xd5,0x7d,0x30,0x67,0x73,0x08,0x09,
50 0xee,0xb7,0x70,0x3f,0x61,0xb2,0x19,0x8e,0x4e,0xe5,0x4b,0x93,0x8f,0x5d,0xdb,0xa9,
51 0xad,0xf1,0xae,0x2e,0xcb,0x0d,0xfc,0xf4,0x2d,0x46,0x6e,0x1d,0x97,0xe8,0xd1,0xe9,
52 0x4d,0x37,0xa5,0x75,0x5e,0x83,0x9e,0xab,0x82,0x9d,0xb9,0x1c,0xe0,0xcd,0x49,0x89,
53 0x01,0xb6,0xbd,0x58,0x24,0xa2,0x5f,0x38,0x78,0x99,0x15,0x90,0x50,0xb8,0x95,0xe4,
54 0xd0,0x91,0xc7,0xce,0xed,0x0f,0xb4,0x6f,0xa0,0xcc,0xf0,0x02,0x4a,0x79,0xc3,0xde,
55 0xa3,0xef,0xea,0x51,0xe6,0x6b,0x18,0xec,0x1b,0x2c,0x80,0xf7,0x74,0xe7,0xff,0x21,
56 0x5a,0x6a,0x54,0x1e,0x41,0x31,0x92,0x35,0xc4,0x33,0x07,0x0a,0xba,0x7e,0x0e,0x34,
57 0x88,0xb1,0x98,0x7c,0xf3,0x3d,0x60,0x6c,0x7b,0xca,0xd3,0x1f,0x32,0x65,0x04,0x28,
58 0x64,0xbe,0x85,0x9b,0x2f,0x59,0x8a,0xd7,0xb0,0x25,0xac,0xaf,0x12,0x03,0xe2,0xf2,
59 };
60
61
62 #define ADD31(a,b) a += (b); a = (a & 0x7fffffff) + (a >> 31)
63 #define ROT31(a,k) ((((a) << (k)) | ((a) >> (31 - (k)))) & 0x7FFFFFFF)
64 #define ROT32(a,k) (((a) << (k)) | ((a) >> (32 - (k))))
65
66 #define L1(X) \
67 ((X) ^ \
68 ROT32((X), 2) ^ \
69 ROT32((X), 10) ^ \
70 ROT32((X), 18) ^ \
71 ROT32((X), 24))
72
73 #define L2(X) \
74 ((X) ^ \
75 ROT32((X), 8) ^ \
76 ROT32((X), 14) ^ \
77 ROT32((X), 22) ^ \
78 ROT32((X), 30))
79
80 #define LFSRWithInitialisationMode(u) \
81 V = LFSR[0]; \
82 ADD31(V, ROT31(LFSR[0], 8)); \
83 ADD31(V, ROT31(LFSR[4], 20)); \
84 ADD31(V, ROT31(LFSR[10], 21)); \
85 ADD31(V, ROT31(LFSR[13], 17)); \
86 ADD31(V, ROT31(LFSR[15], 15)); \
87 ADD31(V, (u)); \
88 {int j; for (j=0; j<15;j++) LFSR[j]=LFSR[j+1];} \
89 LFSR[15] = V
90
91 #define LFSRWithWorkMode() \
92 { \
93 int j; \
94 uint64_t a = LFSR[0]; \
95 a += ((uint64_t)LFSR[0]) << 8; \
96 a += ((uint64_t)LFSR[4]) << 20; \
97 a += ((uint64_t)LFSR[10]) << 21; \
98 a += ((uint64_t)LFSR[13]) << 17; \
99 a += ((uint64_t)LFSR[15]) << 15; \
100 a = (a & 0x7fffffff) + (a >> 31); \
101 V = (a & 0x7fffffff) + (a >> 31); \
102 for (j = 0; j < 15; j++) \
103 LFSR[j] = LFSR[j+1]; \
104 LFSR[15] = V; \
105 }
106
107 #define BitReconstruction2(X1,X2) \
108 X1 = ((LFSR[11] & 0xFFFF) << 16) | (LFSR[9] >> 15); \
109 X2 = ((LFSR[7] & 0xFFFF) << 16) | (LFSR[5] >> 15)
110
111 #define BitReconstruction3(X0,X1,X2) \
112 X0 = ((LFSR[15] & 0x7FFF8000) << 1) | (LFSR[14] & 0xFFFF); \
113 BitReconstruction2(X1,X2)
114
115 #define BitReconstruction4(X0,X1,X2,X3) \
116 BitReconstruction3(X0,X1,X2); \
117 X3 = ((LFSR[2] & 0xFFFF) << 16) | (LFSR[0] >> 15)
118
119
120 #define MAKEU31(k,d,iv) \
121 (((uint32_t)(k) << 23) | \
122 ((uint32_t)(d) << 8) | \
123 (uint32_t)(iv))
124
125 #define MAKEU32(a, b, c, d) \
126 (((uint32_t)(a) << 24) | \
127 ((uint32_t)(b) << 16) | \
128 ((uint32_t)(c) << 8) | \
129 ((uint32_t)(d)))
130
131 #define F_(X1,X2) \
132 W1 = R1 + X1; \
133 W2 = R2 ^ X2; \
134 U = L1((W1 << 16) | (W2 >> 16)); \
135 V = L2((W2 << 16) | (W1 >> 16)); \
136 R1 = MAKEU32( S0[U >> 24], \
137 S1[(U >> 16) & 0xFF], \
138 S0[(U >> 8) & 0xFF], \
139 S1[U & 0xFF]); \
140 R2 = MAKEU32( S0[V >> 24], \
141 S1[(V >> 16) & 0xFF], \
142 S0[(V >> 8) & 0xFF], \
143 S1[V & 0xFF])
144
145 #define F(X0,X1,X2) \
146 (X0 ^ R1) + R2; \
147 F_(X1, X2)
148
zuc_init(ZUC_STATE * state,const uint8_t * user_key,const uint8_t * iv)149 void zuc_init(ZUC_STATE *state, const uint8_t *user_key, const uint8_t *iv)
150 {
151 ZUC_UINT31 *LFSR = state->LFSR;
152 uint32_t R1, R2;
153 uint32_t X0, X1, X2;
154 uint32_t W, W1, W2, U, V;
155 int i;
156
157 for (i = 0; i < 16; i++) {
158 LFSR[i] = MAKEU31(user_key[i], KD[i], iv[i]);
159 }
160
161 R1 = 0;
162 R2 = 0;
163
164 for (i = 0; i < 32; i++) {
165 BitReconstruction3(X0, X1, X2);
166 W = F(X0, X1, X2);
167 LFSRWithInitialisationMode(W >> 1);
168 }
169
170 BitReconstruction2(X1, X2);
171 F_(X1, X2);
172 LFSRWithWorkMode();
173
174 state->R1 = R1;
175 state->R2 = R2;
176 }
177
zuc_generate_keyword(ZUC_STATE * state)178 uint32_t zuc_generate_keyword(ZUC_STATE *state)
179 {
180 ZUC_UINT31 *LFSR = state->LFSR;
181 uint32_t R1 = state->R1;
182 uint32_t R2 = state->R2;
183 uint32_t X0, X1, X2, X3;
184 uint32_t W1, W2, U, V;
185 uint32_t Z;
186
187 BitReconstruction4(X0, X1, X2, X3);
188 Z = X3 ^ F(X0, X1, X2);
189 LFSRWithWorkMode();
190
191 state->R1 = R1;
192 state->R2 = R2;
193
194 return Z;
195 }
196
zuc_generate_keystream(ZUC_STATE * state,size_t nwords,uint32_t * keystream)197 void zuc_generate_keystream(ZUC_STATE *state, size_t nwords, uint32_t *keystream)
198 {
199 ZUC_UINT31 *LFSR = state->LFSR;
200 uint32_t R1 = state->R1;
201 uint32_t R2 = state->R2;
202 uint32_t X0, X1, X2, X3;
203 uint32_t W1, W2, U, V;
204 size_t i;
205
206 for (i = 0; i < nwords; i ++) {
207 BitReconstruction4(X0, X1, X2, X3);
208 keystream[i] = X3 ^ F(X0, X1, X2);
209 LFSRWithWorkMode();
210 }
211
212 state->R1 = R1;
213 state->R2 = R2;
214 }
215
zuc_encrypt(ZUC_STATE * state,const uint8_t * in,size_t inlen,uint8_t * out)216 void zuc_encrypt(ZUC_STATE *state, const uint8_t *in, size_t inlen, uint8_t *out)
217 {
218 ZUC_UINT31 *LFSR = state->LFSR;
219 uint32_t R1 = state->R1;
220 uint32_t R2 = state->R2;
221 uint32_t X0, X1, X2, X3;
222 uint32_t W1, W2, U, V;
223 uint32_t Z;
224 uint8_t block[4];
225 size_t nwords = inlen / sizeof(uint32_t);
226 size_t i;
227
228 for (i = 0; i < nwords; i ++) {
229 BitReconstruction4(X0, X1, X2, X3);
230 Z = X3 ^ F(X0, X1, X2);
231 LFSRWithWorkMode();
232 PUTU32(block, Z);
233 gmssl_memxor(out, in, block, sizeof(block));
234 in += sizeof(block);
235 out += sizeof(block);
236 }
237 if (inlen % 4) {
238 // TODO: use assert to make sure this branch should not be arrived
239 BitReconstruction4(X0, X1, X2, X3);
240 Z = X3 ^ F(X0, X1, X2);
241 LFSRWithWorkMode();
242 PUTU32(block, Z);
243 gmssl_memxor(out, in, block, inlen % 4);
244 }
245
246 state->R1 = R1;
247 state->R2 = R2;
248 }
249
zuc_mac_init(ZUC_MAC_CTX * ctx,const uint8_t key[16],const uint8_t iv[16])250 void zuc_mac_init(ZUC_MAC_CTX *ctx, const uint8_t key[16], const uint8_t iv[16])
251 {
252 memset(ctx, 0, sizeof(*ctx));
253 zuc_init((ZUC_STATE *)ctx, key, iv);
254 ctx->K0 = zuc_generate_keyword((ZUC_STATE *)ctx);
255 }
256
zuc_mac_update(ZUC_MAC_CTX * ctx,const uint8_t * data,size_t len)257 void zuc_mac_update(ZUC_MAC_CTX *ctx, const uint8_t *data, size_t len)
258 {
259 ZUC_UINT32 T = ctx->T;
260 ZUC_UINT32 K0 = ctx->K0;
261 ZUC_UINT32 K1, M;
262 ZUC_UINT31 *LFSR = ctx->LFSR;
263 ZUC_UINT32 R1 = ctx->R1;
264 ZUC_UINT32 R2 = ctx->R2;
265 ZUC_UINT32 X0, X1, X2, X3;
266 ZUC_UINT32 W1, W2, U, V;
267 size_t i;
268
269 if (!data || !len) {
270 return;
271 }
272
273 if (ctx->buflen) {
274 size_t num = sizeof(ctx->buf) - ctx->buflen;
275 if (len < num) {
276 memcpy(ctx->buf + ctx->buflen, data, len);
277 ctx->buflen += len;
278 return;
279 }
280
281 memcpy(ctx->buf + ctx->buflen, data, num);
282 M = GETU32(ctx->buf);
283 ctx->buflen = 0;
284
285 BitReconstruction4(X0, X1, X2, X3);
286 K1 = X3 ^ F(X0, X1, X2);
287 LFSRWithWorkMode();
288
289 for (i = 0; i < 32; i++) {
290 if (M & 0x80000000) {
291 T ^= K0;
292 }
293 M <<= 1;
294 K0 = (K0 << 1) | (K1 >> 31);
295 K1 <<= 1;
296 }
297
298 data += num;
299 len -= num;
300 }
301
302 while (len >= 4) {
303 M = GETU32(data);
304
305 BitReconstruction4(X0, X1, X2, X3);
306 K1 = X3 ^ F(X0, X1, X2);
307 LFSRWithWorkMode();
308
309 for (i = 0; i < 32; i++) {
310 if (M & 0x80000000) {
311 T ^= K0;
312 }
313 M <<= 1;
314 K0 = (K0 << 1) | (K1 >> 31);
315 K1 <<= 1;
316 }
317
318 data += 4;
319 len -= 4;
320 }
321
322 if (len) {
323 memcpy(ctx->buf, data, len);
324 ctx->buflen = len;
325 }
326 ctx->R1 = R1;
327 ctx->R2 = R2;
328 ctx->K0 = K0;
329 ctx->T = T;
330 }
331
zuc_mac_finish(ZUC_MAC_CTX * ctx,const uint8_t * data,size_t nbits,uint8_t mac[4])332 void zuc_mac_finish(ZUC_MAC_CTX *ctx, const uint8_t *data, size_t nbits, uint8_t mac[4])
333 {
334 ZUC_UINT32 T = ctx->T;
335 ZUC_UINT32 K0 = ctx->K0;
336 ZUC_UINT32 K1, M;
337 ZUC_UINT31 *LFSR = ctx->LFSR;
338 ZUC_UINT32 R1 = ctx->R1;
339 ZUC_UINT32 R2 = ctx->R2;
340 ZUC_UINT32 X0, X1, X2, X3;
341 ZUC_UINT32 W1, W2, U, V;
342 size_t i;
343
344
345 if (!data)
346 nbits = 0;
347
348 if (nbits >= 8) {
349 zuc_mac_update(ctx, data, nbits/8);
350 data += nbits/8;
351 nbits %= 8;
352 }
353
354 T = ctx->T;
355 K0 = ctx->K0;
356 LFSR = ctx->LFSR;
357 R1 = ctx->R1;
358 R2 = ctx->R2;
359
360
361 if (nbits)
362 ctx->buf[ctx->buflen] = *data;
363
364 if (ctx->buflen || nbits) {
365 M = GETU32(ctx->buf);
366 BitReconstruction4(X0, X1, X2, X3);
367 K1 = X3 ^ F(X0, X1, X2);
368 LFSRWithWorkMode();
369
370 for (i = 0; i < ctx->buflen * 8 + nbits; i++) {
371 if (M & 0x80000000) {
372 T ^= K0;
373 }
374 M <<= 1;
375 K0 = (K0 << 1) | (K1 >> 31);
376 K1 <<= 1;
377 }
378 }
379
380 T ^= K0;
381
382 BitReconstruction4(X0, X1, X2, X3);
383 K1 = X3 ^ F(X0, X1, X2);
384 LFSRWithWorkMode();
385 T ^= K1;
386
387 ctx->T = T;
388 PUTU32(mac, T);
389
390 memset(ctx, 0, sizeof(*ctx));
391 }
392
393
394 typedef uint8_t ZUC_UINT7;
395
396 static const ZUC_UINT7 ZUC256_D[][16] = {
397 {0x22,0x2F,0x24,0x2A,0x6D,0x40,0x40,0x40,
398 0x40,0x40,0x40,0x40,0x40,0x52,0x10,0x30},
399 {0x22,0x2F,0x25,0x2A,0x6D,0x40,0x40,0x40,
400 0x40,0x40,0x40,0x40,0x40,0x52,0x10,0x30},
401 {0x23,0x2F,0x24,0x2A,0x6D,0x40,0x40,0x40,
402 0x40,0x40,0x40,0x40,0x40,0x52,0x10,0x30},
403 {0x23,0x2F,0x25,0x2A,0x6D,0x40,0x40,0x40,
404 0x40,0x40,0x40,0x40,0x40,0x52,0x10,0x30},
405 };
406
407 #define ZUC256_MAKEU31(a,b,c,d) \
408 (((uint32_t)(a) << 23) | \
409 ((uint32_t)(b) << 16) | \
410 ((uint32_t)(c) << 8) | \
411 (uint32_t)(d))
412
413
zuc256_set_mac_key(ZUC_STATE * key,const uint8_t K[32],const uint8_t IV[23],int macbits)414 static void zuc256_set_mac_key(ZUC_STATE *key, const uint8_t K[32],
415 const uint8_t IV[23], int macbits)
416 {
417 ZUC_UINT31 *LFSR = key->LFSR;
418 uint32_t R1, R2;
419 uint32_t X0, X1, X2;
420 uint32_t W, W1, W2, U, V;
421 const ZUC_UINT7 *D;
422 int i;
423
424 ZUC_UINT6 IV17 = IV[17] >> 2;
425 ZUC_UINT6 IV18 = ((IV[17] & 0x3) << 4) | (IV[18] >> 4);
426 ZUC_UINT6 IV19 = ((IV[18] & 0xf) << 2) | (IV[19] >> 6);
427 ZUC_UINT6 IV20 = IV[19] & 0x3f;
428 ZUC_UINT6 IV21 = IV[20] >> 2;
429 ZUC_UINT6 IV22 = ((IV[20] & 0x3) << 4) | (IV[21] >> 4);
430 ZUC_UINT6 IV23 = ((IV[21] & 0xf) << 2) | (IV[22] >> 6);
431 ZUC_UINT6 IV24 = IV[22] & 0x3f;
432
433 D = macbits/32 < 3 ? ZUC256_D[macbits/32] : ZUC256_D[3];
434 LFSR[0] = ZUC256_MAKEU31(K[0], D[0], K[21], K[16]);
435 LFSR[1] = ZUC256_MAKEU31(K[1], D[1], K[22], K[17]);
436 LFSR[2] = ZUC256_MAKEU31(K[2], D[2], K[23], K[18]);
437 LFSR[3] = ZUC256_MAKEU31(K[3], D[3], K[24], K[19]);
438 LFSR[4] = ZUC256_MAKEU31(K[4], D[4], K[25], K[20]);
439 LFSR[5] = ZUC256_MAKEU31(IV[0], (D[5] | IV17), K[5], K[26]);
440 LFSR[6] = ZUC256_MAKEU31(IV[1], (D[6] | IV18), K[6], K[27]);
441 LFSR[7] = ZUC256_MAKEU31(IV[10], (D[7] | IV19), K[7], IV[2]);
442 LFSR[8] = ZUC256_MAKEU31(K[8], (D[8] | IV20), IV[3], IV[11]);
443 LFSR[9] = ZUC256_MAKEU31(K[9], (D[9] | IV21), IV[12], IV[4]);
444 LFSR[10] = ZUC256_MAKEU31(IV[5], (D[10] | IV22), K[10], K[28]);
445 LFSR[11] = ZUC256_MAKEU31(K[11], (D[11] | IV23), IV[6], IV[13]);
446 LFSR[12] = ZUC256_MAKEU31(K[12], (D[12] | IV24), IV[7], IV[14]);
447 LFSR[13] = ZUC256_MAKEU31(K[13], D[13], IV[15], IV[8]);
448 LFSR[14] = ZUC256_MAKEU31(K[14], (D[14] | (K[31] >> 4)), IV[16], IV[9]);
449 LFSR[15] = ZUC256_MAKEU31(K[15], (D[15] | (K[31] & 0x0F)), K[30], K[29]);
450
451 R1 = 0;
452 R2 = 0;
453
454 for (i = 0; i < 32; i++) {
455 BitReconstruction3(X0, X1, X2);
456 W = F(X0, X1, X2);
457 LFSRWithInitialisationMode(W >> 1);
458 }
459
460 BitReconstruction2(X1, X2);
461 F_(X1, X2);
462 LFSRWithWorkMode();
463
464 key->R1 = R1;
465 key->R2 = R2;
466 }
467
zuc256_init(ZUC_STATE * key,const uint8_t K[32],const uint8_t IV[23])468 void zuc256_init(ZUC_STATE *key, const uint8_t K[32],
469 const uint8_t IV[23])
470 {
471 zuc256_set_mac_key(key, K, IV, 0);
472 }
473
zuc256_mac_init(ZUC256_MAC_CTX * ctx,const uint8_t key[32],const uint8_t iv[23],int macbits)474 void zuc256_mac_init(ZUC256_MAC_CTX *ctx, const uint8_t key[32],
475 const uint8_t iv[23], int macbits)
476 {
477 if (macbits < 32)
478 macbits = 32;
479 else if (macbits > 64)
480 macbits = 128;
481 memset(ctx, 0, sizeof(*ctx));
482 zuc256_set_mac_key((ZUC256_STATE *)ctx, key, iv, macbits);
483 zuc256_generate_keystream((ZUC256_STATE *)ctx, macbits/32, ctx->T);
484 zuc256_generate_keystream((ZUC256_STATE *)ctx, macbits/32, ctx->K0);
485 ctx->macbits = (macbits/32) * 32;
486 }
487
zuc256_mac_update(ZUC256_MAC_CTX * ctx,const uint8_t * data,size_t len)488 void zuc256_mac_update(ZUC256_MAC_CTX *ctx, const uint8_t *data, size_t len)
489 {
490 ZUC_UINT32 K1, M;
491 size_t n = ctx->macbits / 32;
492 size_t i, j;
493
494 if (!data || !len) {
495 return;
496 }
497
498 if (ctx->buflen) {
499 size_t num = sizeof(ctx->buf) - ctx->buflen;
500 if (len < num) {
501 memcpy(ctx->buf + ctx->buflen, data, len);
502 ctx->buflen += len;
503 return;
504 }
505
506 memcpy(ctx->buf + ctx->buflen, data, num);
507 M = GETU32(ctx->buf);
508 ctx->buflen = 0;
509
510 K1 = zuc256_generate_keyword((ZUC256_STATE *)ctx);
511
512 for (i = 0; i < 32; i++) {
513 if (M & 0x80000000) {
514 for (j = 0; j < n; j++) {
515 ctx->T[j] ^= ctx->K0[j];
516 }
517 }
518 M <<= 1;
519 for (j = 0; j < n - 1; j++) {
520 ctx->K0[j] = (ctx->K0[j] << 1) | (ctx->K0[j + 1] >> 31);
521 }
522 ctx->K0[j] = (ctx->K0[j] << 1) | (K1 >> 31);
523 K1 <<= 1;
524 }
525
526 data += num;
527 len -= num;
528 }
529
530 while (len >= 4) {
531 M = GETU32(data);
532 K1 = zuc256_generate_keyword((ZUC256_STATE *)ctx);
533
534 for (i = 0; i < 32; i++) {
535 if (M & 0x80000000) {
536 for (j = 0; j < n; j++) {
537 ctx->T[j] ^= ctx->K0[j];
538 }
539 }
540 M <<= 1;
541 for (j = 0; j < n - 1; j++) {
542 ctx->K0[j] = (ctx->K0[j] << 1) | (ctx->K0[j + 1] >> 31);
543 }
544 ctx->K0[j] = (ctx->K0[j] << 1) | (K1 >> 31);
545 K1 <<= 1;
546 }
547
548 data += 4;
549 len -= 4;
550 }
551
552 if (len) {
553 memcpy(ctx->buf, data, len);
554 ctx->buflen = len;
555 }
556 }
557
zuc256_mac_finish(ZUC256_MAC_CTX * ctx,const uint8_t * data,size_t nbits,uint8_t * mac)558 void zuc256_mac_finish(ZUC256_MAC_CTX *ctx, const uint8_t *data, size_t nbits, uint8_t *mac)
559 {
560 ZUC_UINT32 K1, M;
561 size_t n = ctx->macbits/32;
562 size_t i, j;
563
564
565 if (!data)
566 nbits = 0;
567
568 if (nbits >= 8) {
569 zuc256_mac_update(ctx, data, nbits/8);
570 data += nbits/8;
571 nbits %= 8;
572 }
573
574 if (nbits)
575 ctx->buf[ctx->buflen] = *data;
576
577 if (ctx->buflen || nbits) {
578 M = GETU32(ctx->buf);
579 K1 = zuc256_generate_keyword((ZUC256_STATE *)ctx);
580
581
582 for (i = 0; i < ctx->buflen * 8 + nbits; i++) {
583 if (M & 0x80000000) {
584 for (j = 0; j < n; j++) {
585 ctx->T[j] ^= ctx->K0[j];
586 }
587 }
588 M <<= 1;
589 for (j = 0; j < n - 1; j++) {
590 ctx->K0[j] = (ctx->K0[j] << 1) | (ctx->K0[j + 1] >> 31);
591 }
592 ctx->K0[j] = (ctx->K0[j] << 1) | (K1 >> 31);
593 K1 <<= 1;
594 }
595 }
596
597 for (j = 0; j < n; j++) {
598 ctx->T[j] ^= ctx->K0[j];
599 PUTU32(mac, ctx->T[j]);
600 mac += 4;
601 }
602
603 memset(ctx, 0, sizeof(*ctx));
604 }
605