1 // SPDX-License-Identifier: GPL-2.0-or-later 1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* 2 /*
3 * CMAC: Cipher Block Mode for Authentication 3 * CMAC: Cipher Block Mode for Authentication
4 * 4 *
5 * Copyright © 2013 Jussi Kivilinna <jussi.ki 5 * Copyright © 2013 Jussi Kivilinna <jussi.kivilinna@iki.fi>
6 * 6 *
7 * Based on work by: 7 * Based on work by:
8 * Copyright © 2013 Tom St Denis <tstdenis@e 8 * Copyright © 2013 Tom St Denis <tstdenis@elliptictech.com>
9 * Based on crypto/xcbc.c: 9 * Based on crypto/xcbc.c:
10 * Copyright © 2006 USAGI/WIDE Project, 10 * Copyright © 2006 USAGI/WIDE Project,
11 * Author: Kazunori Miyazawa <miyazawa@linux 11 * Author: Kazunori Miyazawa <miyazawa@linux-ipv6.org>
12 */ 12 */
13 13
14 #include <crypto/internal/cipher.h> 14 #include <crypto/internal/cipher.h>
15 #include <crypto/internal/hash.h> 15 #include <crypto/internal/hash.h>
16 #include <linux/err.h> 16 #include <linux/err.h>
17 #include <linux/kernel.h> 17 #include <linux/kernel.h>
18 #include <linux/module.h> 18 #include <linux/module.h>
19 19
20 /* 20 /*
21 * +------------------------ 21 * +------------------------
22 * | <parent tfm> 22 * | <parent tfm>
23 * +------------------------ 23 * +------------------------
24 * | cmac_tfm_ctx 24 * | cmac_tfm_ctx
25 * +------------------------ 25 * +------------------------
26 * | consts (block size * 2) 26 * | consts (block size * 2)
27 * +------------------------ 27 * +------------------------
28 */ 28 */
29 struct cmac_tfm_ctx { 29 struct cmac_tfm_ctx {
30 struct crypto_cipher *child; 30 struct crypto_cipher *child;
31 __be64 consts[]; !! 31 u8 ctx[];
32 }; 32 };
33 33
34 /* 34 /*
35 * +------------------------ 35 * +------------------------
36 * | <shash desc> 36 * | <shash desc>
37 * +------------------------ 37 * +------------------------
38 * | cmac_desc_ctx 38 * | cmac_desc_ctx
39 * +------------------------ 39 * +------------------------
40 * | odds (block size) 40 * | odds (block size)
41 * +------------------------ 41 * +------------------------
42 * | prev (block size) 42 * | prev (block size)
43 * +------------------------ 43 * +------------------------
44 */ 44 */
45 struct cmac_desc_ctx { 45 struct cmac_desc_ctx {
46 unsigned int len; 46 unsigned int len;
47 u8 odds[]; !! 47 u8 ctx[];
48 }; 48 };
49 49
50 static int crypto_cmac_digest_setkey(struct cr 50 static int crypto_cmac_digest_setkey(struct crypto_shash *parent,
51 const u8 51 const u8 *inkey, unsigned int keylen)
52 { 52 {
>> 53 unsigned long alignmask = crypto_shash_alignmask(parent);
53 struct cmac_tfm_ctx *ctx = crypto_shas 54 struct cmac_tfm_ctx *ctx = crypto_shash_ctx(parent);
54 unsigned int bs = crypto_shash_blocksi 55 unsigned int bs = crypto_shash_blocksize(parent);
55 __be64 *consts = ctx->consts; !! 56 __be64 *consts = PTR_ALIGN((void *)ctx->ctx,
>> 57 (alignmask | (__alignof__(__be64) - 1)) + 1);
56 u64 _const[2]; 58 u64 _const[2];
57 int i, err = 0; 59 int i, err = 0;
58 u8 msb_mask, gfmask; 60 u8 msb_mask, gfmask;
59 61
60 err = crypto_cipher_setkey(ctx->child, 62 err = crypto_cipher_setkey(ctx->child, inkey, keylen);
61 if (err) 63 if (err)
62 return err; 64 return err;
63 65
64 /* encrypt the zero block */ 66 /* encrypt the zero block */
65 memset(consts, 0, bs); 67 memset(consts, 0, bs);
66 crypto_cipher_encrypt_one(ctx->child, 68 crypto_cipher_encrypt_one(ctx->child, (u8 *)consts, (u8 *)consts);
67 69
68 switch (bs) { 70 switch (bs) {
69 case 16: 71 case 16:
70 gfmask = 0x87; 72 gfmask = 0x87;
71 _const[0] = be64_to_cpu(consts 73 _const[0] = be64_to_cpu(consts[1]);
72 _const[1] = be64_to_cpu(consts 74 _const[1] = be64_to_cpu(consts[0]);
73 75
74 /* gf(2^128) multiply zero-cip 76 /* gf(2^128) multiply zero-ciphertext with u and u^2 */
75 for (i = 0; i < 4; i += 2) { 77 for (i = 0; i < 4; i += 2) {
76 msb_mask = ((s64)_cons 78 msb_mask = ((s64)_const[1] >> 63) & gfmask;
77 _const[1] = (_const[1] 79 _const[1] = (_const[1] << 1) | (_const[0] >> 63);
78 _const[0] = (_const[0] 80 _const[0] = (_const[0] << 1) ^ msb_mask;
79 81
80 consts[i + 0] = cpu_to 82 consts[i + 0] = cpu_to_be64(_const[1]);
81 consts[i + 1] = cpu_to 83 consts[i + 1] = cpu_to_be64(_const[0]);
82 } 84 }
83 85
84 break; 86 break;
85 case 8: 87 case 8:
86 gfmask = 0x1B; 88 gfmask = 0x1B;
87 _const[0] = be64_to_cpu(consts 89 _const[0] = be64_to_cpu(consts[0]);
88 90
89 /* gf(2^64) multiply zero-ciph 91 /* gf(2^64) multiply zero-ciphertext with u and u^2 */
90 for (i = 0; i < 2; i++) { 92 for (i = 0; i < 2; i++) {
91 msb_mask = ((s64)_cons 93 msb_mask = ((s64)_const[0] >> 63) & gfmask;
92 _const[0] = (_const[0] 94 _const[0] = (_const[0] << 1) ^ msb_mask;
93 95
94 consts[i] = cpu_to_be6 96 consts[i] = cpu_to_be64(_const[0]);
95 } 97 }
96 98
97 break; 99 break;
98 } 100 }
99 101
100 return 0; 102 return 0;
101 } 103 }
102 104
103 static int crypto_cmac_digest_init(struct shas 105 static int crypto_cmac_digest_init(struct shash_desc *pdesc)
104 { 106 {
>> 107 unsigned long alignmask = crypto_shash_alignmask(pdesc->tfm);
105 struct cmac_desc_ctx *ctx = shash_desc 108 struct cmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
106 int bs = crypto_shash_blocksize(pdesc- 109 int bs = crypto_shash_blocksize(pdesc->tfm);
107 u8 *prev = &ctx->odds[bs]; !! 110 u8 *prev = PTR_ALIGN((void *)ctx->ctx, alignmask + 1) + bs;
108 111
109 ctx->len = 0; 112 ctx->len = 0;
110 memset(prev, 0, bs); 113 memset(prev, 0, bs);
111 114
112 return 0; 115 return 0;
113 } 116 }
114 117
115 static int crypto_cmac_digest_update(struct sh 118 static int crypto_cmac_digest_update(struct shash_desc *pdesc, const u8 *p,
116 unsigned 119 unsigned int len)
117 { 120 {
118 struct crypto_shash *parent = pdesc->t 121 struct crypto_shash *parent = pdesc->tfm;
>> 122 unsigned long alignmask = crypto_shash_alignmask(parent);
119 struct cmac_tfm_ctx *tctx = crypto_sha 123 struct cmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
120 struct cmac_desc_ctx *ctx = shash_desc 124 struct cmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
121 struct crypto_cipher *tfm = tctx->chil 125 struct crypto_cipher *tfm = tctx->child;
122 int bs = crypto_shash_blocksize(parent 126 int bs = crypto_shash_blocksize(parent);
123 u8 *odds = ctx->odds; !! 127 u8 *odds = PTR_ALIGN((void *)ctx->ctx, alignmask + 1);
124 u8 *prev = odds + bs; 128 u8 *prev = odds + bs;
125 129
126 /* checking the data can fill the bloc 130 /* checking the data can fill the block */
127 if ((ctx->len + len) <= bs) { 131 if ((ctx->len + len) <= bs) {
128 memcpy(odds + ctx->len, p, len 132 memcpy(odds + ctx->len, p, len);
129 ctx->len += len; 133 ctx->len += len;
130 return 0; 134 return 0;
131 } 135 }
132 136
133 /* filling odds with new data and encr 137 /* filling odds with new data and encrypting it */
134 memcpy(odds + ctx->len, p, bs - ctx->l 138 memcpy(odds + ctx->len, p, bs - ctx->len);
135 len -= bs - ctx->len; 139 len -= bs - ctx->len;
136 p += bs - ctx->len; 140 p += bs - ctx->len;
137 141
138 crypto_xor(prev, odds, bs); 142 crypto_xor(prev, odds, bs);
139 crypto_cipher_encrypt_one(tfm, prev, p 143 crypto_cipher_encrypt_one(tfm, prev, prev);
140 144
141 /* clearing the length */ 145 /* clearing the length */
142 ctx->len = 0; 146 ctx->len = 0;
143 147
144 /* encrypting the rest of data */ 148 /* encrypting the rest of data */
145 while (len > bs) { 149 while (len > bs) {
146 crypto_xor(prev, p, bs); 150 crypto_xor(prev, p, bs);
147 crypto_cipher_encrypt_one(tfm, 151 crypto_cipher_encrypt_one(tfm, prev, prev);
148 p += bs; 152 p += bs;
149 len -= bs; 153 len -= bs;
150 } 154 }
151 155
152 /* keeping the surplus of blocksize */ 156 /* keeping the surplus of blocksize */
153 if (len) { 157 if (len) {
154 memcpy(odds, p, len); 158 memcpy(odds, p, len);
155 ctx->len = len; 159 ctx->len = len;
156 } 160 }
157 161
158 return 0; 162 return 0;
159 } 163 }
160 164
161 static int crypto_cmac_digest_final(struct sha 165 static int crypto_cmac_digest_final(struct shash_desc *pdesc, u8 *out)
162 { 166 {
163 struct crypto_shash *parent = pdesc->t 167 struct crypto_shash *parent = pdesc->tfm;
>> 168 unsigned long alignmask = crypto_shash_alignmask(parent);
164 struct cmac_tfm_ctx *tctx = crypto_sha 169 struct cmac_tfm_ctx *tctx = crypto_shash_ctx(parent);
165 struct cmac_desc_ctx *ctx = shash_desc 170 struct cmac_desc_ctx *ctx = shash_desc_ctx(pdesc);
166 struct crypto_cipher *tfm = tctx->chil 171 struct crypto_cipher *tfm = tctx->child;
167 int bs = crypto_shash_blocksize(parent 172 int bs = crypto_shash_blocksize(parent);
168 u8 *odds = ctx->odds; !! 173 u8 *consts = PTR_ALIGN((void *)tctx->ctx,
>> 174 (alignmask | (__alignof__(__be64) - 1)) + 1);
>> 175 u8 *odds = PTR_ALIGN((void *)ctx->ctx, alignmask + 1);
169 u8 *prev = odds + bs; 176 u8 *prev = odds + bs;
170 unsigned int offset = 0; 177 unsigned int offset = 0;
171 178
172 if (ctx->len != bs) { 179 if (ctx->len != bs) {
173 unsigned int rlen; 180 unsigned int rlen;
174 u8 *p = odds + ctx->len; 181 u8 *p = odds + ctx->len;
175 182
176 *p = 0x80; 183 *p = 0x80;
177 p++; 184 p++;
178 185
179 rlen = bs - ctx->len - 1; 186 rlen = bs - ctx->len - 1;
180 if (rlen) 187 if (rlen)
181 memset(p, 0, rlen); 188 memset(p, 0, rlen);
182 189
183 offset += bs; 190 offset += bs;
184 } 191 }
185 192
186 crypto_xor(prev, odds, bs); 193 crypto_xor(prev, odds, bs);
187 crypto_xor(prev, (const u8 *)tctx->con !! 194 crypto_xor(prev, consts + offset, bs);
188 195
189 crypto_cipher_encrypt_one(tfm, out, pr 196 crypto_cipher_encrypt_one(tfm, out, prev);
190 197
191 return 0; 198 return 0;
192 } 199 }
193 200
194 static int cmac_init_tfm(struct crypto_shash * !! 201 static int cmac_init_tfm(struct crypto_tfm *tfm)
195 { 202 {
196 struct shash_instance *inst = shash_al <<
197 struct cmac_tfm_ctx *ctx = crypto_shas <<
198 struct crypto_cipher_spawn *spawn; <<
199 struct crypto_cipher *cipher; 203 struct crypto_cipher *cipher;
>> 204 struct crypto_instance *inst = (void *)tfm->__crt_alg;
>> 205 struct crypto_cipher_spawn *spawn = crypto_instance_ctx(inst);
>> 206 struct cmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
200 207
201 spawn = shash_instance_ctx(inst); <<
202 cipher = crypto_spawn_cipher(spawn); 208 cipher = crypto_spawn_cipher(spawn);
203 if (IS_ERR(cipher)) 209 if (IS_ERR(cipher))
204 return PTR_ERR(cipher); 210 return PTR_ERR(cipher);
205 211
206 ctx->child = cipher; 212 ctx->child = cipher;
207 213
208 return 0; 214 return 0;
209 } !! 215 };
210 <<
211 static int cmac_clone_tfm(struct crypto_shash <<
212 { <<
213 struct cmac_tfm_ctx *octx = crypto_sha <<
214 struct cmac_tfm_ctx *ctx = crypto_shas <<
215 struct crypto_cipher *cipher; <<
216 <<
217 cipher = crypto_clone_cipher(octx->chi <<
218 if (IS_ERR(cipher)) <<
219 return PTR_ERR(cipher); <<
220 <<
221 ctx->child = cipher; <<
222 <<
223 return 0; <<
224 } <<
225 216
226 static void cmac_exit_tfm(struct crypto_shash !! 217 static void cmac_exit_tfm(struct crypto_tfm *tfm)
227 { 218 {
228 struct cmac_tfm_ctx *ctx = crypto_shas !! 219 struct cmac_tfm_ctx *ctx = crypto_tfm_ctx(tfm);
229 crypto_free_cipher(ctx->child); 220 crypto_free_cipher(ctx->child);
230 } 221 }
231 222
232 static int cmac_create(struct crypto_template 223 static int cmac_create(struct crypto_template *tmpl, struct rtattr **tb)
233 { 224 {
234 struct shash_instance *inst; 225 struct shash_instance *inst;
235 struct crypto_cipher_spawn *spawn; 226 struct crypto_cipher_spawn *spawn;
236 struct crypto_alg *alg; 227 struct crypto_alg *alg;
>> 228 unsigned long alignmask;
237 u32 mask; 229 u32 mask;
238 int err; 230 int err;
239 231
240 err = crypto_check_attr_type(tb, CRYPT 232 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH, &mask);
241 if (err) 233 if (err)
242 return err; 234 return err;
243 235
244 inst = kzalloc(sizeof(*inst) + sizeof( 236 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
245 if (!inst) 237 if (!inst)
246 return -ENOMEM; 238 return -ENOMEM;
247 spawn = shash_instance_ctx(inst); 239 spawn = shash_instance_ctx(inst);
248 240
249 err = crypto_grab_cipher(spawn, shash_ 241 err = crypto_grab_cipher(spawn, shash_crypto_instance(inst),
250 crypto_attr_a 242 crypto_attr_alg_name(tb[1]), 0, mask);
251 if (err) 243 if (err)
252 goto err_free_inst; 244 goto err_free_inst;
253 alg = crypto_spawn_cipher_alg(spawn); 245 alg = crypto_spawn_cipher_alg(spawn);
254 246
255 switch (alg->cra_blocksize) { 247 switch (alg->cra_blocksize) {
256 case 16: 248 case 16:
257 case 8: 249 case 8:
258 break; 250 break;
259 default: 251 default:
260 err = -EINVAL; 252 err = -EINVAL;
261 goto err_free_inst; 253 goto err_free_inst;
262 } 254 }
263 255
264 err = crypto_inst_setname(shash_crypto 256 err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg);
265 if (err) 257 if (err)
266 goto err_free_inst; 258 goto err_free_inst;
267 259
>> 260 alignmask = alg->cra_alignmask;
>> 261 inst->alg.base.cra_alignmask = alignmask;
268 inst->alg.base.cra_priority = alg->cra 262 inst->alg.base.cra_priority = alg->cra_priority;
269 inst->alg.base.cra_blocksize = alg->cr 263 inst->alg.base.cra_blocksize = alg->cra_blocksize;
270 inst->alg.base.cra_ctxsize = sizeof(st <<
271 alg->cra_ <<
272 264
273 inst->alg.digestsize = alg->cra_blocks 265 inst->alg.digestsize = alg->cra_blocksize;
274 inst->alg.descsize = sizeof(struct cma !! 266 inst->alg.descsize =
275 alg->cra_blocksiz !! 267 ALIGN(sizeof(struct cmac_desc_ctx), crypto_tfm_ctx_alignment())
>> 268 + (alignmask & ~(crypto_tfm_ctx_alignment() - 1))
>> 269 + alg->cra_blocksize * 2;
>> 270
>> 271 inst->alg.base.cra_ctxsize =
>> 272 ALIGN(sizeof(struct cmac_tfm_ctx), crypto_tfm_ctx_alignment())
>> 273 + ((alignmask | (__alignof__(__be64) - 1)) &
>> 274 ~(crypto_tfm_ctx_alignment() - 1))
>> 275 + alg->cra_blocksize * 2;
>> 276
>> 277 inst->alg.base.cra_init = cmac_init_tfm;
>> 278 inst->alg.base.cra_exit = cmac_exit_tfm;
>> 279
276 inst->alg.init = crypto_cmac_digest_in 280 inst->alg.init = crypto_cmac_digest_init;
277 inst->alg.update = crypto_cmac_digest_ 281 inst->alg.update = crypto_cmac_digest_update;
278 inst->alg.final = crypto_cmac_digest_f 282 inst->alg.final = crypto_cmac_digest_final;
279 inst->alg.setkey = crypto_cmac_digest_ 283 inst->alg.setkey = crypto_cmac_digest_setkey;
280 inst->alg.init_tfm = cmac_init_tfm; <<
281 inst->alg.clone_tfm = cmac_clone_tfm; <<
282 inst->alg.exit_tfm = cmac_exit_tfm; <<
283 284
284 inst->free = shash_free_singlespawn_in 285 inst->free = shash_free_singlespawn_instance;
285 286
286 err = shash_register_instance(tmpl, in 287 err = shash_register_instance(tmpl, inst);
287 if (err) { 288 if (err) {
288 err_free_inst: 289 err_free_inst:
289 shash_free_singlespawn_instanc 290 shash_free_singlespawn_instance(inst);
290 } 291 }
291 return err; 292 return err;
292 } 293 }
293 294
294 static struct crypto_template crypto_cmac_tmpl 295 static struct crypto_template crypto_cmac_tmpl = {
295 .name = "cmac", 296 .name = "cmac",
296 .create = cmac_create, 297 .create = cmac_create,
297 .module = THIS_MODULE, 298 .module = THIS_MODULE,
298 }; 299 };
299 300
300 static int __init crypto_cmac_module_init(void 301 static int __init crypto_cmac_module_init(void)
301 { 302 {
302 return crypto_register_template(&crypt 303 return crypto_register_template(&crypto_cmac_tmpl);
303 } 304 }
304 305
305 static void __exit crypto_cmac_module_exit(voi 306 static void __exit crypto_cmac_module_exit(void)
306 { 307 {
307 crypto_unregister_template(&crypto_cma 308 crypto_unregister_template(&crypto_cmac_tmpl);
308 } 309 }
309 310
310 subsys_initcall(crypto_cmac_module_init); 311 subsys_initcall(crypto_cmac_module_init);
311 module_exit(crypto_cmac_module_exit); 312 module_exit(crypto_cmac_module_exit);
312 313
313 MODULE_LICENSE("GPL"); 314 MODULE_LICENSE("GPL");
314 MODULE_DESCRIPTION("CMAC keyed hash algorithm" 315 MODULE_DESCRIPTION("CMAC keyed hash algorithm");
315 MODULE_ALIAS_CRYPTO("cmac"); 316 MODULE_ALIAS_CRYPTO("cmac");
316 MODULE_IMPORT_NS(CRYPTO_INTERNAL); 317 MODULE_IMPORT_NS(CRYPTO_INTERNAL);
317 318
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