GNU Linux-libre 5.13.14-gnu1
[releases.git] / arch / s390 / crypto / des_s390.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Cryptographic API.
4  *
5  * s390 implementation of the DES Cipher Algorithm.
6  *
7  * Copyright IBM Corp. 2003, 2011
8  * Author(s): Thomas Spatzier
9  *            Jan Glauber (jan.glauber@de.ibm.com)
10  */
11
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/cpufeature.h>
15 #include <linux/crypto.h>
16 #include <linux/fips.h>
17 #include <linux/mutex.h>
18 #include <crypto/algapi.h>
19 #include <crypto/internal/des.h>
20 #include <crypto/internal/skcipher.h>
21 #include <asm/cpacf.h>
22
23 #define DES3_KEY_SIZE   (3 * DES_KEY_SIZE)
24
25 static u8 *ctrblk;
26 static DEFINE_MUTEX(ctrblk_lock);
27
28 static cpacf_mask_t km_functions, kmc_functions, kmctr_functions;
29
30 struct s390_des_ctx {
31         u8 iv[DES_BLOCK_SIZE];
32         u8 key[DES3_KEY_SIZE];
33 };
34
35 static int des_setkey(struct crypto_tfm *tfm, const u8 *key,
36                       unsigned int key_len)
37 {
38         struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
39         int err;
40
41         err = crypto_des_verify_key(tfm, key);
42         if (err)
43                 return err;
44
45         memcpy(ctx->key, key, key_len);
46         return 0;
47 }
48
49 static int des_setkey_skcipher(struct crypto_skcipher *tfm, const u8 *key,
50                                unsigned int key_len)
51 {
52         return des_setkey(crypto_skcipher_tfm(tfm), key, key_len);
53 }
54
55 static void s390_des_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
56 {
57         struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
58
59         cpacf_km(CPACF_KM_DEA, ctx->key, out, in, DES_BLOCK_SIZE);
60 }
61
62 static void s390_des_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
63 {
64         struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
65
66         cpacf_km(CPACF_KM_DEA | CPACF_DECRYPT,
67                  ctx->key, out, in, DES_BLOCK_SIZE);
68 }
69
70 static struct crypto_alg des_alg = {
71         .cra_name               =       "des",
72         .cra_driver_name        =       "des-s390",
73         .cra_priority           =       300,
74         .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
75         .cra_blocksize          =       DES_BLOCK_SIZE,
76         .cra_ctxsize            =       sizeof(struct s390_des_ctx),
77         .cra_module             =       THIS_MODULE,
78         .cra_u                  =       {
79                 .cipher = {
80                         .cia_min_keysize        =       DES_KEY_SIZE,
81                         .cia_max_keysize        =       DES_KEY_SIZE,
82                         .cia_setkey             =       des_setkey,
83                         .cia_encrypt            =       s390_des_encrypt,
84                         .cia_decrypt            =       s390_des_decrypt,
85                 }
86         }
87 };
88
89 static int ecb_desall_crypt(struct skcipher_request *req, unsigned long fc)
90 {
91         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
92         struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
93         struct skcipher_walk walk;
94         unsigned int nbytes, n;
95         int ret;
96
97         ret = skcipher_walk_virt(&walk, req, false);
98         while ((nbytes = walk.nbytes) != 0) {
99                 /* only use complete blocks */
100                 n = nbytes & ~(DES_BLOCK_SIZE - 1);
101                 cpacf_km(fc, ctx->key, walk.dst.virt.addr,
102                          walk.src.virt.addr, n);
103                 ret = skcipher_walk_done(&walk, nbytes - n);
104         }
105         return ret;
106 }
107
108 static int cbc_desall_crypt(struct skcipher_request *req, unsigned long fc)
109 {
110         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
111         struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
112         struct skcipher_walk walk;
113         unsigned int nbytes, n;
114         int ret;
115         struct {
116                 u8 iv[DES_BLOCK_SIZE];
117                 u8 key[DES3_KEY_SIZE];
118         } param;
119
120         ret = skcipher_walk_virt(&walk, req, false);
121         if (ret)
122                 return ret;
123         memcpy(param.iv, walk.iv, DES_BLOCK_SIZE);
124         memcpy(param.key, ctx->key, DES3_KEY_SIZE);
125         while ((nbytes = walk.nbytes) != 0) {
126                 /* only use complete blocks */
127                 n = nbytes & ~(DES_BLOCK_SIZE - 1);
128                 cpacf_kmc(fc, &param, walk.dst.virt.addr,
129                           walk.src.virt.addr, n);
130                 memcpy(walk.iv, param.iv, DES_BLOCK_SIZE);
131                 ret = skcipher_walk_done(&walk, nbytes - n);
132         }
133         return ret;
134 }
135
136 static int ecb_des_encrypt(struct skcipher_request *req)
137 {
138         return ecb_desall_crypt(req, CPACF_KM_DEA);
139 }
140
141 static int ecb_des_decrypt(struct skcipher_request *req)
142 {
143         return ecb_desall_crypt(req, CPACF_KM_DEA | CPACF_DECRYPT);
144 }
145
146 static struct skcipher_alg ecb_des_alg = {
147         .base.cra_name          =       "ecb(des)",
148         .base.cra_driver_name   =       "ecb-des-s390",
149         .base.cra_priority      =       400,    /* combo: des + ecb */
150         .base.cra_blocksize     =       DES_BLOCK_SIZE,
151         .base.cra_ctxsize       =       sizeof(struct s390_des_ctx),
152         .base.cra_module        =       THIS_MODULE,
153         .min_keysize            =       DES_KEY_SIZE,
154         .max_keysize            =       DES_KEY_SIZE,
155         .setkey                 =       des_setkey_skcipher,
156         .encrypt                =       ecb_des_encrypt,
157         .decrypt                =       ecb_des_decrypt,
158 };
159
160 static int cbc_des_encrypt(struct skcipher_request *req)
161 {
162         return cbc_desall_crypt(req, CPACF_KMC_DEA);
163 }
164
165 static int cbc_des_decrypt(struct skcipher_request *req)
166 {
167         return cbc_desall_crypt(req, CPACF_KMC_DEA | CPACF_DECRYPT);
168 }
169
170 static struct skcipher_alg cbc_des_alg = {
171         .base.cra_name          =       "cbc(des)",
172         .base.cra_driver_name   =       "cbc-des-s390",
173         .base.cra_priority      =       400,    /* combo: des + cbc */
174         .base.cra_blocksize     =       DES_BLOCK_SIZE,
175         .base.cra_ctxsize       =       sizeof(struct s390_des_ctx),
176         .base.cra_module        =       THIS_MODULE,
177         .min_keysize            =       DES_KEY_SIZE,
178         .max_keysize            =       DES_KEY_SIZE,
179         .ivsize                 =       DES_BLOCK_SIZE,
180         .setkey                 =       des_setkey_skcipher,
181         .encrypt                =       cbc_des_encrypt,
182         .decrypt                =       cbc_des_decrypt,
183 };
184
185 /*
186  * RFC2451:
187  *
188  *   For DES-EDE3, there is no known need to reject weak or
189  *   complementation keys.  Any weakness is obviated by the use of
190  *   multiple keys.
191  *
192  *   However, if the first two or last two independent 64-bit keys are
193  *   equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
194  *   same as DES.  Implementers MUST reject keys that exhibit this
195  *   property.
196  *
197  *   In fips mode additinally check for all 3 keys are unique.
198  *
199  */
200 static int des3_setkey(struct crypto_tfm *tfm, const u8 *key,
201                        unsigned int key_len)
202 {
203         struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
204         int err;
205
206         err = crypto_des3_ede_verify_key(tfm, key);
207         if (err)
208                 return err;
209
210         memcpy(ctx->key, key, key_len);
211         return 0;
212 }
213
214 static int des3_setkey_skcipher(struct crypto_skcipher *tfm, const u8 *key,
215                                 unsigned int key_len)
216 {
217         return des3_setkey(crypto_skcipher_tfm(tfm), key, key_len);
218 }
219
220 static void des3_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
221 {
222         struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
223
224         cpacf_km(CPACF_KM_TDEA_192, ctx->key, dst, src, DES_BLOCK_SIZE);
225 }
226
227 static void des3_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
228 {
229         struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
230
231         cpacf_km(CPACF_KM_TDEA_192 | CPACF_DECRYPT,
232                  ctx->key, dst, src, DES_BLOCK_SIZE);
233 }
234
235 static struct crypto_alg des3_alg = {
236         .cra_name               =       "des3_ede",
237         .cra_driver_name        =       "des3_ede-s390",
238         .cra_priority           =       300,
239         .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
240         .cra_blocksize          =       DES_BLOCK_SIZE,
241         .cra_ctxsize            =       sizeof(struct s390_des_ctx),
242         .cra_module             =       THIS_MODULE,
243         .cra_u                  =       {
244                 .cipher = {
245                         .cia_min_keysize        =       DES3_KEY_SIZE,
246                         .cia_max_keysize        =       DES3_KEY_SIZE,
247                         .cia_setkey             =       des3_setkey,
248                         .cia_encrypt            =       des3_encrypt,
249                         .cia_decrypt            =       des3_decrypt,
250                 }
251         }
252 };
253
254 static int ecb_des3_encrypt(struct skcipher_request *req)
255 {
256         return ecb_desall_crypt(req, CPACF_KM_TDEA_192);
257 }
258
259 static int ecb_des3_decrypt(struct skcipher_request *req)
260 {
261         return ecb_desall_crypt(req, CPACF_KM_TDEA_192 | CPACF_DECRYPT);
262 }
263
264 static struct skcipher_alg ecb_des3_alg = {
265         .base.cra_name          =       "ecb(des3_ede)",
266         .base.cra_driver_name   =       "ecb-des3_ede-s390",
267         .base.cra_priority      =       400,    /* combo: des3 + ecb */
268         .base.cra_blocksize     =       DES_BLOCK_SIZE,
269         .base.cra_ctxsize       =       sizeof(struct s390_des_ctx),
270         .base.cra_module        =       THIS_MODULE,
271         .min_keysize            =       DES3_KEY_SIZE,
272         .max_keysize            =       DES3_KEY_SIZE,
273         .setkey                 =       des3_setkey_skcipher,
274         .encrypt                =       ecb_des3_encrypt,
275         .decrypt                =       ecb_des3_decrypt,
276 };
277
278 static int cbc_des3_encrypt(struct skcipher_request *req)
279 {
280         return cbc_desall_crypt(req, CPACF_KMC_TDEA_192);
281 }
282
283 static int cbc_des3_decrypt(struct skcipher_request *req)
284 {
285         return cbc_desall_crypt(req, CPACF_KMC_TDEA_192 | CPACF_DECRYPT);
286 }
287
288 static struct skcipher_alg cbc_des3_alg = {
289         .base.cra_name          =       "cbc(des3_ede)",
290         .base.cra_driver_name   =       "cbc-des3_ede-s390",
291         .base.cra_priority      =       400,    /* combo: des3 + cbc */
292         .base.cra_blocksize     =       DES_BLOCK_SIZE,
293         .base.cra_ctxsize       =       sizeof(struct s390_des_ctx),
294         .base.cra_module        =       THIS_MODULE,
295         .min_keysize            =       DES3_KEY_SIZE,
296         .max_keysize            =       DES3_KEY_SIZE,
297         .ivsize                 =       DES_BLOCK_SIZE,
298         .setkey                 =       des3_setkey_skcipher,
299         .encrypt                =       cbc_des3_encrypt,
300         .decrypt                =       cbc_des3_decrypt,
301 };
302
303 static unsigned int __ctrblk_init(u8 *ctrptr, u8 *iv, unsigned int nbytes)
304 {
305         unsigned int i, n;
306
307         /* align to block size, max. PAGE_SIZE */
308         n = (nbytes > PAGE_SIZE) ? PAGE_SIZE : nbytes & ~(DES_BLOCK_SIZE - 1);
309         memcpy(ctrptr, iv, DES_BLOCK_SIZE);
310         for (i = (n / DES_BLOCK_SIZE) - 1; i > 0; i--) {
311                 memcpy(ctrptr + DES_BLOCK_SIZE, ctrptr, DES_BLOCK_SIZE);
312                 crypto_inc(ctrptr + DES_BLOCK_SIZE, DES_BLOCK_SIZE);
313                 ctrptr += DES_BLOCK_SIZE;
314         }
315         return n;
316 }
317
318 static int ctr_desall_crypt(struct skcipher_request *req, unsigned long fc)
319 {
320         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
321         struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
322         u8 buf[DES_BLOCK_SIZE], *ctrptr;
323         struct skcipher_walk walk;
324         unsigned int n, nbytes;
325         int ret, locked;
326
327         locked = mutex_trylock(&ctrblk_lock);
328
329         ret = skcipher_walk_virt(&walk, req, false);
330         while ((nbytes = walk.nbytes) >= DES_BLOCK_SIZE) {
331                 n = DES_BLOCK_SIZE;
332                 if (nbytes >= 2*DES_BLOCK_SIZE && locked)
333                         n = __ctrblk_init(ctrblk, walk.iv, nbytes);
334                 ctrptr = (n > DES_BLOCK_SIZE) ? ctrblk : walk.iv;
335                 cpacf_kmctr(fc, ctx->key, walk.dst.virt.addr,
336                             walk.src.virt.addr, n, ctrptr);
337                 if (ctrptr == ctrblk)
338                         memcpy(walk.iv, ctrptr + n - DES_BLOCK_SIZE,
339                                 DES_BLOCK_SIZE);
340                 crypto_inc(walk.iv, DES_BLOCK_SIZE);
341                 ret = skcipher_walk_done(&walk, nbytes - n);
342         }
343         if (locked)
344                 mutex_unlock(&ctrblk_lock);
345         /* final block may be < DES_BLOCK_SIZE, copy only nbytes */
346         if (nbytes) {
347                 cpacf_kmctr(fc, ctx->key, buf, walk.src.virt.addr,
348                             DES_BLOCK_SIZE, walk.iv);
349                 memcpy(walk.dst.virt.addr, buf, nbytes);
350                 crypto_inc(walk.iv, DES_BLOCK_SIZE);
351                 ret = skcipher_walk_done(&walk, 0);
352         }
353         return ret;
354 }
355
356 static int ctr_des_crypt(struct skcipher_request *req)
357 {
358         return ctr_desall_crypt(req, CPACF_KMCTR_DEA);
359 }
360
361 static struct skcipher_alg ctr_des_alg = {
362         .base.cra_name          =       "ctr(des)",
363         .base.cra_driver_name   =       "ctr-des-s390",
364         .base.cra_priority      =       400,    /* combo: des + ctr */
365         .base.cra_blocksize     =       1,
366         .base.cra_ctxsize       =       sizeof(struct s390_des_ctx),
367         .base.cra_module        =       THIS_MODULE,
368         .min_keysize            =       DES_KEY_SIZE,
369         .max_keysize            =       DES_KEY_SIZE,
370         .ivsize                 =       DES_BLOCK_SIZE,
371         .setkey                 =       des_setkey_skcipher,
372         .encrypt                =       ctr_des_crypt,
373         .decrypt                =       ctr_des_crypt,
374         .chunksize              =       DES_BLOCK_SIZE,
375 };
376
377 static int ctr_des3_crypt(struct skcipher_request *req)
378 {
379         return ctr_desall_crypt(req, CPACF_KMCTR_TDEA_192);
380 }
381
382 static struct skcipher_alg ctr_des3_alg = {
383         .base.cra_name          =       "ctr(des3_ede)",
384         .base.cra_driver_name   =       "ctr-des3_ede-s390",
385         .base.cra_priority      =       400,    /* combo: des3 + ede */
386         .base.cra_blocksize     =       1,
387         .base.cra_ctxsize       =       sizeof(struct s390_des_ctx),
388         .base.cra_module        =       THIS_MODULE,
389         .min_keysize            =       DES3_KEY_SIZE,
390         .max_keysize            =       DES3_KEY_SIZE,
391         .ivsize                 =       DES_BLOCK_SIZE,
392         .setkey                 =       des3_setkey_skcipher,
393         .encrypt                =       ctr_des3_crypt,
394         .decrypt                =       ctr_des3_crypt,
395         .chunksize              =       DES_BLOCK_SIZE,
396 };
397
398 static struct crypto_alg *des_s390_algs_ptr[2];
399 static int des_s390_algs_num;
400 static struct skcipher_alg *des_s390_skciphers_ptr[6];
401 static int des_s390_skciphers_num;
402
403 static int des_s390_register_alg(struct crypto_alg *alg)
404 {
405         int ret;
406
407         ret = crypto_register_alg(alg);
408         if (!ret)
409                 des_s390_algs_ptr[des_s390_algs_num++] = alg;
410         return ret;
411 }
412
413 static int des_s390_register_skcipher(struct skcipher_alg *alg)
414 {
415         int ret;
416
417         ret = crypto_register_skcipher(alg);
418         if (!ret)
419                 des_s390_skciphers_ptr[des_s390_skciphers_num++] = alg;
420         return ret;
421 }
422
423 static void des_s390_exit(void)
424 {
425         while (des_s390_algs_num--)
426                 crypto_unregister_alg(des_s390_algs_ptr[des_s390_algs_num]);
427         while (des_s390_skciphers_num--)
428                 crypto_unregister_skcipher(des_s390_skciphers_ptr[des_s390_skciphers_num]);
429         if (ctrblk)
430                 free_page((unsigned long) ctrblk);
431 }
432
433 static int __init des_s390_init(void)
434 {
435         int ret;
436
437         /* Query available functions for KM, KMC and KMCTR */
438         cpacf_query(CPACF_KM, &km_functions);
439         cpacf_query(CPACF_KMC, &kmc_functions);
440         cpacf_query(CPACF_KMCTR, &kmctr_functions);
441
442         if (cpacf_test_func(&km_functions, CPACF_KM_DEA)) {
443                 ret = des_s390_register_alg(&des_alg);
444                 if (ret)
445                         goto out_err;
446                 ret = des_s390_register_skcipher(&ecb_des_alg);
447                 if (ret)
448                         goto out_err;
449         }
450         if (cpacf_test_func(&kmc_functions, CPACF_KMC_DEA)) {
451                 ret = des_s390_register_skcipher(&cbc_des_alg);
452                 if (ret)
453                         goto out_err;
454         }
455         if (cpacf_test_func(&km_functions, CPACF_KM_TDEA_192)) {
456                 ret = des_s390_register_alg(&des3_alg);
457                 if (ret)
458                         goto out_err;
459                 ret = des_s390_register_skcipher(&ecb_des3_alg);
460                 if (ret)
461                         goto out_err;
462         }
463         if (cpacf_test_func(&kmc_functions, CPACF_KMC_TDEA_192)) {
464                 ret = des_s390_register_skcipher(&cbc_des3_alg);
465                 if (ret)
466                         goto out_err;
467         }
468
469         if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_DEA) ||
470             cpacf_test_func(&kmctr_functions, CPACF_KMCTR_TDEA_192)) {
471                 ctrblk = (u8 *) __get_free_page(GFP_KERNEL);
472                 if (!ctrblk) {
473                         ret = -ENOMEM;
474                         goto out_err;
475                 }
476         }
477
478         if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_DEA)) {
479                 ret = des_s390_register_skcipher(&ctr_des_alg);
480                 if (ret)
481                         goto out_err;
482         }
483         if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_TDEA_192)) {
484                 ret = des_s390_register_skcipher(&ctr_des3_alg);
485                 if (ret)
486                         goto out_err;
487         }
488
489         return 0;
490 out_err:
491         des_s390_exit();
492         return ret;
493 }
494
495 module_cpu_feature_match(MSA, des_s390_init);
496 module_exit(des_s390_exit);
497
498 MODULE_ALIAS_CRYPTO("des");
499 MODULE_ALIAS_CRYPTO("des3_ede");
500
501 MODULE_LICENSE("GPL");
502 MODULE_DESCRIPTION("DES & Triple DES EDE Cipher Algorithms");