1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Cryptographic API.
4 *
5 * s390 implementation of the AES Cipher Algorithm with protected keys.
6 *
7 * s390 Version:
8 * Copyright IBM Corp. 2017, 2023
9 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
10 * Harald Freudenberger <freude@de.ibm.com>
11 */
12
13 #define KMSG_COMPONENT "paes_s390"
14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15
16 #include <crypto/aes.h>
17 #include <crypto/algapi.h>
18 #include <linux/bug.h>
19 #include <linux/err.h>
20 #include <linux/module.h>
21 #include <linux/cpufeature.h>
22 #include <linux/init.h>
23 #include <linux/mutex.h>
24 #include <linux/spinlock.h>
25 #include <linux/delay.h>
26 #include <crypto/internal/skcipher.h>
27 #include <crypto/xts.h>
28 #include <asm/cpacf.h>
29 #include <asm/pkey.h>
30
31 /*
32 * Key blobs smaller/bigger than these defines are rejected
33 * by the common code even before the individual setkey function
34 * is called. As paes can handle different kinds of key blobs
35 * and padding is also possible, the limits need to be generous.
36 */
37 #define PAES_MIN_KEYSIZE 16
38 #define PAES_MAX_KEYSIZE MAXEP11AESKEYBLOBSIZE
39 #define PAES_256_PROTKEY_SIZE (32 + 32) /* key + verification pattern */
40 #define PXTS_256_PROTKEY_SIZE (32 + 32 + 32) /* k1 + k2 + verification pattern */
41
42 static u8 *ctrblk;
43 static DEFINE_MUTEX(ctrblk_lock);
44
45 static cpacf_mask_t km_functions, kmc_functions, kmctr_functions;
46
47 struct paes_protkey {
48 u32 type;
49 u32 len;
50 u8 protkey[PXTS_256_PROTKEY_SIZE];
51 };
52
53 struct key_blob {
54 /*
55 * Small keys will be stored in the keybuf. Larger keys are
56 * stored in extra allocated memory. In both cases does
57 * key point to the memory where the key is stored.
58 * The code distinguishes by checking keylen against
59 * sizeof(keybuf). See the two following helper functions.
60 */
61 u8 *key;
62 u8 keybuf[128];
63 unsigned int keylen;
64 };
65
66 /*
67 * make_clrkey_token() - wrap the raw key ck with pkey clearkey token
68 * information.
69 * @returns the size of the clearkey token
70 */
make_clrkey_token(const u8 * ck,size_t cklen,u8 * dest)71 static inline u32 make_clrkey_token(const u8 *ck, size_t cklen, u8 *dest)
72 {
73 struct clrkey_token {
74 u8 type;
75 u8 res0[3];
76 u8 version;
77 u8 res1[3];
78 u32 keytype;
79 u32 len;
80 u8 key[];
81 } __packed *token = (struct clrkey_token *)dest;
82
83 token->type = 0x00;
84 token->version = 0x02;
85 token->keytype = (cklen - 8) >> 3;
86 token->len = cklen;
87 memcpy(token->key, ck, cklen);
88
89 return sizeof(*token) + cklen;
90 }
91
_key_to_kb(struct key_blob * kb,const u8 * key,unsigned int keylen)92 static inline int _key_to_kb(struct key_blob *kb,
93 const u8 *key,
94 unsigned int keylen)
95 {
96 switch (keylen) {
97 case 16:
98 case 24:
99 case 32:
100 /* clear key value, prepare pkey clear key token in keybuf */
101 memset(kb->keybuf, 0, sizeof(kb->keybuf));
102 kb->keylen = make_clrkey_token(key, keylen, kb->keybuf);
103 kb->key = kb->keybuf;
104 break;
105 default:
106 /* other key material, let pkey handle this */
107 if (keylen <= sizeof(kb->keybuf))
108 kb->key = kb->keybuf;
109 else {
110 kb->key = kmalloc(keylen, GFP_KERNEL);
111 if (!kb->key)
112 return -ENOMEM;
113 }
114 memcpy(kb->key, key, keylen);
115 kb->keylen = keylen;
116 break;
117 }
118
119 return 0;
120 }
121
_xts_key_to_kb(struct key_blob * kb,const u8 * key,unsigned int keylen)122 static inline int _xts_key_to_kb(struct key_blob *kb,
123 const u8 *key,
124 unsigned int keylen)
125 {
126 size_t cklen = keylen / 2;
127
128 memset(kb->keybuf, 0, sizeof(kb->keybuf));
129
130 switch (keylen) {
131 case 32:
132 case 64:
133 /* clear key value, prepare pkey clear key tokens in keybuf */
134 kb->key = kb->keybuf;
135 kb->keylen = make_clrkey_token(key, cklen, kb->key);
136 kb->keylen += make_clrkey_token(key + cklen, cklen,
137 kb->key + kb->keylen);
138 break;
139 default:
140 /* other key material, let pkey handle this */
141 if (keylen <= sizeof(kb->keybuf)) {
142 kb->key = kb->keybuf;
143 } else {
144 kb->key = kmalloc(keylen, GFP_KERNEL);
145 if (!kb->key)
146 return -ENOMEM;
147 }
148 memcpy(kb->key, key, keylen);
149 kb->keylen = keylen;
150 break;
151 }
152
153 return 0;
154 }
155
_free_kb_keybuf(struct key_blob * kb)156 static inline void _free_kb_keybuf(struct key_blob *kb)
157 {
158 if (kb->key && kb->key != kb->keybuf
159 && kb->keylen > sizeof(kb->keybuf)) {
160 kfree_sensitive(kb->key);
161 kb->key = NULL;
162 }
163 memzero_explicit(kb->keybuf, sizeof(kb->keybuf));
164 }
165
166 struct s390_paes_ctx {
167 struct key_blob kb;
168 struct paes_protkey pk;
169 spinlock_t pk_lock;
170 unsigned long fc;
171 };
172
173 struct s390_pxts_ctx {
174 struct key_blob kb;
175 struct paes_protkey pk[2];
176 spinlock_t pk_lock;
177 unsigned long fc;
178 };
179
__paes_keyblob2pkey(const u8 * key,unsigned int keylen,struct paes_protkey * pk)180 static inline int __paes_keyblob2pkey(const u8 *key, unsigned int keylen,
181 struct paes_protkey *pk)
182 {
183 int i, rc = -EIO;
184
185 /* try three times in case of busy card */
186 for (i = 0; rc && i < 3; i++) {
187 if (rc == -EBUSY && in_task()) {
188 if (msleep_interruptible(1000))
189 return -EINTR;
190 }
191 rc = pkey_key2protkey(key, keylen, pk->protkey, &pk->len,
192 &pk->type);
193 }
194
195 return rc;
196 }
197
__paes_convert_key(struct s390_paes_ctx * ctx)198 static inline int __paes_convert_key(struct s390_paes_ctx *ctx)
199 {
200 struct paes_protkey pk;
201 int rc;
202
203 pk.len = sizeof(pk.protkey);
204 rc = __paes_keyblob2pkey(ctx->kb.key, ctx->kb.keylen, &pk);
205 if (rc)
206 return rc;
207
208 spin_lock_bh(&ctx->pk_lock);
209 memcpy(&ctx->pk, &pk, sizeof(pk));
210 spin_unlock_bh(&ctx->pk_lock);
211
212 return 0;
213 }
214
ecb_paes_init(struct crypto_skcipher * tfm)215 static int ecb_paes_init(struct crypto_skcipher *tfm)
216 {
217 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
218
219 ctx->kb.key = NULL;
220 spin_lock_init(&ctx->pk_lock);
221
222 return 0;
223 }
224
ecb_paes_exit(struct crypto_skcipher * tfm)225 static void ecb_paes_exit(struct crypto_skcipher *tfm)
226 {
227 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
228
229 _free_kb_keybuf(&ctx->kb);
230 }
231
__ecb_paes_set_key(struct s390_paes_ctx * ctx)232 static inline int __ecb_paes_set_key(struct s390_paes_ctx *ctx)
233 {
234 unsigned long fc;
235 int rc;
236
237 rc = __paes_convert_key(ctx);
238 if (rc)
239 return rc;
240
241 /* Pick the correct function code based on the protected key type */
242 fc = (ctx->pk.type == PKEY_KEYTYPE_AES_128) ? CPACF_KM_PAES_128 :
243 (ctx->pk.type == PKEY_KEYTYPE_AES_192) ? CPACF_KM_PAES_192 :
244 (ctx->pk.type == PKEY_KEYTYPE_AES_256) ? CPACF_KM_PAES_256 : 0;
245
246 /* Check if the function code is available */
247 ctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0;
248
249 return ctx->fc ? 0 : -EINVAL;
250 }
251
ecb_paes_set_key(struct crypto_skcipher * tfm,const u8 * in_key,unsigned int key_len)252 static int ecb_paes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
253 unsigned int key_len)
254 {
255 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
256 int rc;
257
258 _free_kb_keybuf(&ctx->kb);
259 rc = _key_to_kb(&ctx->kb, in_key, key_len);
260 if (rc)
261 return rc;
262
263 return __ecb_paes_set_key(ctx);
264 }
265
ecb_paes_crypt(struct skcipher_request * req,unsigned long modifier)266 static int ecb_paes_crypt(struct skcipher_request *req, unsigned long modifier)
267 {
268 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
269 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
270 struct {
271 u8 key[PAES_256_PROTKEY_SIZE];
272 } param;
273 struct skcipher_walk walk;
274 unsigned int nbytes, n, k;
275 int rc;
276
277 rc = skcipher_walk_virt(&walk, req, false);
278 if (rc)
279 return rc;
280
281 spin_lock_bh(&ctx->pk_lock);
282 memcpy(param.key, ctx->pk.protkey, PAES_256_PROTKEY_SIZE);
283 spin_unlock_bh(&ctx->pk_lock);
284
285 while ((nbytes = walk.nbytes) != 0) {
286 /* only use complete blocks */
287 n = nbytes & ~(AES_BLOCK_SIZE - 1);
288 k = cpacf_km(ctx->fc | modifier, ¶m,
289 walk.dst.virt.addr, walk.src.virt.addr, n);
290 if (k)
291 rc = skcipher_walk_done(&walk, nbytes - k);
292 if (k < n) {
293 if (__paes_convert_key(ctx))
294 return skcipher_walk_done(&walk, -EIO);
295 spin_lock_bh(&ctx->pk_lock);
296 memcpy(param.key, ctx->pk.protkey, PAES_256_PROTKEY_SIZE);
297 spin_unlock_bh(&ctx->pk_lock);
298 }
299 }
300 return rc;
301 }
302
ecb_paes_encrypt(struct skcipher_request * req)303 static int ecb_paes_encrypt(struct skcipher_request *req)
304 {
305 return ecb_paes_crypt(req, 0);
306 }
307
ecb_paes_decrypt(struct skcipher_request * req)308 static int ecb_paes_decrypt(struct skcipher_request *req)
309 {
310 return ecb_paes_crypt(req, CPACF_DECRYPT);
311 }
312
313 static struct skcipher_alg ecb_paes_alg = {
314 .base.cra_name = "ecb(paes)",
315 .base.cra_driver_name = "ecb-paes-s390",
316 .base.cra_priority = 401, /* combo: aes + ecb + 1 */
317 .base.cra_blocksize = AES_BLOCK_SIZE,
318 .base.cra_ctxsize = sizeof(struct s390_paes_ctx),
319 .base.cra_module = THIS_MODULE,
320 .base.cra_list = LIST_HEAD_INIT(ecb_paes_alg.base.cra_list),
321 .init = ecb_paes_init,
322 .exit = ecb_paes_exit,
323 .min_keysize = PAES_MIN_KEYSIZE,
324 .max_keysize = PAES_MAX_KEYSIZE,
325 .setkey = ecb_paes_set_key,
326 .encrypt = ecb_paes_encrypt,
327 .decrypt = ecb_paes_decrypt,
328 };
329
cbc_paes_init(struct crypto_skcipher * tfm)330 static int cbc_paes_init(struct crypto_skcipher *tfm)
331 {
332 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
333
334 ctx->kb.key = NULL;
335 spin_lock_init(&ctx->pk_lock);
336
337 return 0;
338 }
339
cbc_paes_exit(struct crypto_skcipher * tfm)340 static void cbc_paes_exit(struct crypto_skcipher *tfm)
341 {
342 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
343
344 _free_kb_keybuf(&ctx->kb);
345 }
346
__cbc_paes_set_key(struct s390_paes_ctx * ctx)347 static inline int __cbc_paes_set_key(struct s390_paes_ctx *ctx)
348 {
349 unsigned long fc;
350 int rc;
351
352 rc = __paes_convert_key(ctx);
353 if (rc)
354 return rc;
355
356 /* Pick the correct function code based on the protected key type */
357 fc = (ctx->pk.type == PKEY_KEYTYPE_AES_128) ? CPACF_KMC_PAES_128 :
358 (ctx->pk.type == PKEY_KEYTYPE_AES_192) ? CPACF_KMC_PAES_192 :
359 (ctx->pk.type == PKEY_KEYTYPE_AES_256) ? CPACF_KMC_PAES_256 : 0;
360
361 /* Check if the function code is available */
362 ctx->fc = (fc && cpacf_test_func(&kmc_functions, fc)) ? fc : 0;
363
364 return ctx->fc ? 0 : -EINVAL;
365 }
366
cbc_paes_set_key(struct crypto_skcipher * tfm,const u8 * in_key,unsigned int key_len)367 static int cbc_paes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
368 unsigned int key_len)
369 {
370 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
371 int rc;
372
373 _free_kb_keybuf(&ctx->kb);
374 rc = _key_to_kb(&ctx->kb, in_key, key_len);
375 if (rc)
376 return rc;
377
378 return __cbc_paes_set_key(ctx);
379 }
380
cbc_paes_crypt(struct skcipher_request * req,unsigned long modifier)381 static int cbc_paes_crypt(struct skcipher_request *req, unsigned long modifier)
382 {
383 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
384 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
385 struct {
386 u8 iv[AES_BLOCK_SIZE];
387 u8 key[PAES_256_PROTKEY_SIZE];
388 } param;
389 struct skcipher_walk walk;
390 unsigned int nbytes, n, k;
391 int rc;
392
393 rc = skcipher_walk_virt(&walk, req, false);
394 if (rc)
395 return rc;
396
397 memcpy(param.iv, walk.iv, AES_BLOCK_SIZE);
398 spin_lock_bh(&ctx->pk_lock);
399 memcpy(param.key, ctx->pk.protkey, PAES_256_PROTKEY_SIZE);
400 spin_unlock_bh(&ctx->pk_lock);
401
402 while ((nbytes = walk.nbytes) != 0) {
403 /* only use complete blocks */
404 n = nbytes & ~(AES_BLOCK_SIZE - 1);
405 k = cpacf_kmc(ctx->fc | modifier, ¶m,
406 walk.dst.virt.addr, walk.src.virt.addr, n);
407 if (k) {
408 memcpy(walk.iv, param.iv, AES_BLOCK_SIZE);
409 rc = skcipher_walk_done(&walk, nbytes - k);
410 }
411 if (k < n) {
412 if (__paes_convert_key(ctx))
413 return skcipher_walk_done(&walk, -EIO);
414 spin_lock_bh(&ctx->pk_lock);
415 memcpy(param.key, ctx->pk.protkey, PAES_256_PROTKEY_SIZE);
416 spin_unlock_bh(&ctx->pk_lock);
417 }
418 }
419 return rc;
420 }
421
cbc_paes_encrypt(struct skcipher_request * req)422 static int cbc_paes_encrypt(struct skcipher_request *req)
423 {
424 return cbc_paes_crypt(req, 0);
425 }
426
cbc_paes_decrypt(struct skcipher_request * req)427 static int cbc_paes_decrypt(struct skcipher_request *req)
428 {
429 return cbc_paes_crypt(req, CPACF_DECRYPT);
430 }
431
432 static struct skcipher_alg cbc_paes_alg = {
433 .base.cra_name = "cbc(paes)",
434 .base.cra_driver_name = "cbc-paes-s390",
435 .base.cra_priority = 402, /* ecb-paes-s390 + 1 */
436 .base.cra_blocksize = AES_BLOCK_SIZE,
437 .base.cra_ctxsize = sizeof(struct s390_paes_ctx),
438 .base.cra_module = THIS_MODULE,
439 .base.cra_list = LIST_HEAD_INIT(cbc_paes_alg.base.cra_list),
440 .init = cbc_paes_init,
441 .exit = cbc_paes_exit,
442 .min_keysize = PAES_MIN_KEYSIZE,
443 .max_keysize = PAES_MAX_KEYSIZE,
444 .ivsize = AES_BLOCK_SIZE,
445 .setkey = cbc_paes_set_key,
446 .encrypt = cbc_paes_encrypt,
447 .decrypt = cbc_paes_decrypt,
448 };
449
xts_paes_init(struct crypto_skcipher * tfm)450 static int xts_paes_init(struct crypto_skcipher *tfm)
451 {
452 struct s390_pxts_ctx *ctx = crypto_skcipher_ctx(tfm);
453
454 ctx->kb.key = NULL;
455 spin_lock_init(&ctx->pk_lock);
456
457 return 0;
458 }
459
xts_paes_exit(struct crypto_skcipher * tfm)460 static void xts_paes_exit(struct crypto_skcipher *tfm)
461 {
462 struct s390_pxts_ctx *ctx = crypto_skcipher_ctx(tfm);
463
464 _free_kb_keybuf(&ctx->kb);
465 }
466
__xts_paes_convert_key(struct s390_pxts_ctx * ctx)467 static inline int __xts_paes_convert_key(struct s390_pxts_ctx *ctx)
468 {
469 struct paes_protkey pk0, pk1;
470 size_t split_keylen;
471 int rc;
472
473 pk0.len = sizeof(pk0.protkey);
474 pk1.len = sizeof(pk1.protkey);
475
476 rc = __paes_keyblob2pkey(ctx->kb.key, ctx->kb.keylen, &pk0);
477 if (rc)
478 return rc;
479
480 switch (pk0.type) {
481 case PKEY_KEYTYPE_AES_128:
482 case PKEY_KEYTYPE_AES_256:
483 /* second keytoken required */
484 if (ctx->kb.keylen % 2)
485 return -EINVAL;
486 split_keylen = ctx->kb.keylen / 2;
487
488 rc = __paes_keyblob2pkey(ctx->kb.key + split_keylen,
489 split_keylen, &pk1);
490 if (rc)
491 return rc;
492
493 if (pk0.type != pk1.type)
494 return -EINVAL;
495 break;
496 case PKEY_KEYTYPE_AES_XTS_128:
497 case PKEY_KEYTYPE_AES_XTS_256:
498 /* single key */
499 pk1.type = 0;
500 break;
501 default:
502 /* unsupported protected keytype */
503 return -EINVAL;
504 }
505
506 spin_lock_bh(&ctx->pk_lock);
507 ctx->pk[0] = pk0;
508 ctx->pk[1] = pk1;
509 spin_unlock_bh(&ctx->pk_lock);
510
511 return 0;
512 }
513
__xts_paes_set_key(struct s390_pxts_ctx * ctx)514 static inline int __xts_paes_set_key(struct s390_pxts_ctx *ctx)
515 {
516 unsigned long fc;
517 int rc;
518
519 rc = __xts_paes_convert_key(ctx);
520 if (rc)
521 return rc;
522
523 /* Pick the correct function code based on the protected key type */
524 switch (ctx->pk[0].type) {
525 case PKEY_KEYTYPE_AES_128:
526 fc = CPACF_KM_PXTS_128;
527 break;
528 case PKEY_KEYTYPE_AES_256:
529 fc = CPACF_KM_PXTS_256;
530 break;
531 case PKEY_KEYTYPE_AES_XTS_128:
532 fc = CPACF_KM_PXTS_128_FULL;
533 break;
534 case PKEY_KEYTYPE_AES_XTS_256:
535 fc = CPACF_KM_PXTS_256_FULL;
536 break;
537 default:
538 fc = 0;
539 break;
540 }
541
542 /* Check if the function code is available */
543 ctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0;
544
545 return ctx->fc ? 0 : -EINVAL;
546 }
547
xts_paes_set_key(struct crypto_skcipher * tfm,const u8 * in_key,unsigned int in_keylen)548 static int xts_paes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
549 unsigned int in_keylen)
550 {
551 struct s390_pxts_ctx *ctx = crypto_skcipher_ctx(tfm);
552 u8 ckey[2 * AES_MAX_KEY_SIZE];
553 unsigned int ckey_len;
554 int rc;
555
556 if ((in_keylen == 32 || in_keylen == 64) &&
557 xts_verify_key(tfm, in_key, in_keylen))
558 return -EINVAL;
559
560 _free_kb_keybuf(&ctx->kb);
561 rc = _xts_key_to_kb(&ctx->kb, in_key, in_keylen);
562 if (rc)
563 return rc;
564
565 rc = __xts_paes_set_key(ctx);
566 if (rc)
567 return rc;
568
569 /*
570 * It is not possible on a single protected key (e.g. full AES-XTS) to
571 * check, if k1 and k2 are the same.
572 */
573 if (ctx->pk[0].type == PKEY_KEYTYPE_AES_XTS_128 ||
574 ctx->pk[0].type == PKEY_KEYTYPE_AES_XTS_256)
575 return 0;
576 /*
577 * xts_verify_key verifies the key length is not odd and makes
578 * sure that the two keys are not the same. This can be done
579 * on the two protected keys as well
580 */
581 ckey_len = (ctx->pk[0].type == PKEY_KEYTYPE_AES_128) ?
582 AES_KEYSIZE_128 : AES_KEYSIZE_256;
583 memcpy(ckey, ctx->pk[0].protkey, ckey_len);
584 memcpy(ckey + ckey_len, ctx->pk[1].protkey, ckey_len);
585 return xts_verify_key(tfm, ckey, 2*ckey_len);
586 }
587
paes_xts_crypt_full(struct skcipher_request * req,unsigned long modifier)588 static int paes_xts_crypt_full(struct skcipher_request *req,
589 unsigned long modifier)
590 {
591 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
592 struct s390_pxts_ctx *ctx = crypto_skcipher_ctx(tfm);
593 unsigned int keylen, offset, nbytes, n, k;
594 struct {
595 u8 key[64];
596 u8 tweak[16];
597 u8 nap[16];
598 u8 wkvp[32];
599 } fxts_param = {
600 .nap = {0},
601 };
602 struct skcipher_walk walk;
603 int rc;
604
605 rc = skcipher_walk_virt(&walk, req, false);
606 if (rc)
607 return rc;
608
609 keylen = (ctx->pk[0].type == PKEY_KEYTYPE_AES_XTS_128) ? 32 : 64;
610 offset = (ctx->pk[0].type == PKEY_KEYTYPE_AES_XTS_128) ? 32 : 0;
611
612 spin_lock_bh(&ctx->pk_lock);
613 memcpy(fxts_param.key + offset, ctx->pk[0].protkey, keylen);
614 memcpy(fxts_param.wkvp, ctx->pk[0].protkey + keylen,
615 sizeof(fxts_param.wkvp));
616 spin_unlock_bh(&ctx->pk_lock);
617 memcpy(fxts_param.tweak, walk.iv, sizeof(fxts_param.tweak));
618 fxts_param.nap[0] = 0x01; /* initial alpha power (1, little-endian) */
619
620 while ((nbytes = walk.nbytes) != 0) {
621 /* only use complete blocks */
622 n = nbytes & ~(AES_BLOCK_SIZE - 1);
623 k = cpacf_km(ctx->fc | modifier, fxts_param.key + offset,
624 walk.dst.virt.addr, walk.src.virt.addr, n);
625 if (k)
626 rc = skcipher_walk_done(&walk, nbytes - k);
627 if (k < n) {
628 if (__xts_paes_convert_key(ctx))
629 return skcipher_walk_done(&walk, -EIO);
630 spin_lock_bh(&ctx->pk_lock);
631 memcpy(fxts_param.key + offset, ctx->pk[0].protkey,
632 keylen);
633 memcpy(fxts_param.wkvp, ctx->pk[0].protkey + keylen,
634 sizeof(fxts_param.wkvp));
635 spin_unlock_bh(&ctx->pk_lock);
636 }
637 }
638
639 return rc;
640 }
641
paes_xts_crypt(struct skcipher_request * req,unsigned long modifier)642 static int paes_xts_crypt(struct skcipher_request *req, unsigned long modifier)
643 {
644 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
645 struct s390_pxts_ctx *ctx = crypto_skcipher_ctx(tfm);
646 unsigned int keylen, offset, nbytes, n, k;
647 struct {
648 u8 key[PAES_256_PROTKEY_SIZE];
649 u8 tweak[16];
650 u8 block[16];
651 u8 bit[16];
652 u8 xts[16];
653 } pcc_param;
654 struct {
655 u8 key[PAES_256_PROTKEY_SIZE];
656 u8 init[16];
657 } xts_param;
658 struct skcipher_walk walk;
659 int rc;
660
661 rc = skcipher_walk_virt(&walk, req, false);
662 if (rc)
663 return rc;
664
665 keylen = (ctx->pk[0].type == PKEY_KEYTYPE_AES_128) ? 48 : 64;
666 offset = (ctx->pk[0].type == PKEY_KEYTYPE_AES_128) ? 16 : 0;
667
668 memset(&pcc_param, 0, sizeof(pcc_param));
669 memcpy(pcc_param.tweak, walk.iv, sizeof(pcc_param.tweak));
670 spin_lock_bh(&ctx->pk_lock);
671 memcpy(pcc_param.key + offset, ctx->pk[1].protkey, keylen);
672 memcpy(xts_param.key + offset, ctx->pk[0].protkey, keylen);
673 spin_unlock_bh(&ctx->pk_lock);
674 cpacf_pcc(ctx->fc, pcc_param.key + offset);
675 memcpy(xts_param.init, pcc_param.xts, 16);
676
677 while ((nbytes = walk.nbytes) != 0) {
678 /* only use complete blocks */
679 n = nbytes & ~(AES_BLOCK_SIZE - 1);
680 k = cpacf_km(ctx->fc | modifier, xts_param.key + offset,
681 walk.dst.virt.addr, walk.src.virt.addr, n);
682 if (k)
683 rc = skcipher_walk_done(&walk, nbytes - k);
684 if (k < n) {
685 if (__xts_paes_convert_key(ctx))
686 return skcipher_walk_done(&walk, -EIO);
687 spin_lock_bh(&ctx->pk_lock);
688 memcpy(xts_param.key + offset,
689 ctx->pk[0].protkey, keylen);
690 spin_unlock_bh(&ctx->pk_lock);
691 }
692 }
693
694 return rc;
695 }
696
xts_paes_crypt(struct skcipher_request * req,unsigned long modifier)697 static inline int xts_paes_crypt(struct skcipher_request *req, unsigned long modifier)
698 {
699 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
700 struct s390_pxts_ctx *ctx = crypto_skcipher_ctx(tfm);
701
702 switch (ctx->fc) {
703 case CPACF_KM_PXTS_128:
704 case CPACF_KM_PXTS_256:
705 return paes_xts_crypt(req, modifier);
706 case CPACF_KM_PXTS_128_FULL:
707 case CPACF_KM_PXTS_256_FULL:
708 return paes_xts_crypt_full(req, modifier);
709 default:
710 return -EINVAL;
711 }
712 }
713
xts_paes_encrypt(struct skcipher_request * req)714 static int xts_paes_encrypt(struct skcipher_request *req)
715 {
716 return xts_paes_crypt(req, 0);
717 }
718
xts_paes_decrypt(struct skcipher_request * req)719 static int xts_paes_decrypt(struct skcipher_request *req)
720 {
721 return xts_paes_crypt(req, CPACF_DECRYPT);
722 }
723
724 static struct skcipher_alg xts_paes_alg = {
725 .base.cra_name = "xts(paes)",
726 .base.cra_driver_name = "xts-paes-s390",
727 .base.cra_priority = 402, /* ecb-paes-s390 + 1 */
728 .base.cra_blocksize = AES_BLOCK_SIZE,
729 .base.cra_ctxsize = sizeof(struct s390_pxts_ctx),
730 .base.cra_module = THIS_MODULE,
731 .base.cra_list = LIST_HEAD_INIT(xts_paes_alg.base.cra_list),
732 .init = xts_paes_init,
733 .exit = xts_paes_exit,
734 .min_keysize = 2 * PAES_MIN_KEYSIZE,
735 .max_keysize = 2 * PAES_MAX_KEYSIZE,
736 .ivsize = AES_BLOCK_SIZE,
737 .setkey = xts_paes_set_key,
738 .encrypt = xts_paes_encrypt,
739 .decrypt = xts_paes_decrypt,
740 };
741
ctr_paes_init(struct crypto_skcipher * tfm)742 static int ctr_paes_init(struct crypto_skcipher *tfm)
743 {
744 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
745
746 ctx->kb.key = NULL;
747 spin_lock_init(&ctx->pk_lock);
748
749 return 0;
750 }
751
ctr_paes_exit(struct crypto_skcipher * tfm)752 static void ctr_paes_exit(struct crypto_skcipher *tfm)
753 {
754 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
755
756 _free_kb_keybuf(&ctx->kb);
757 }
758
__ctr_paes_set_key(struct s390_paes_ctx * ctx)759 static inline int __ctr_paes_set_key(struct s390_paes_ctx *ctx)
760 {
761 unsigned long fc;
762 int rc;
763
764 rc = __paes_convert_key(ctx);
765 if (rc)
766 return rc;
767
768 /* Pick the correct function code based on the protected key type */
769 fc = (ctx->pk.type == PKEY_KEYTYPE_AES_128) ? CPACF_KMCTR_PAES_128 :
770 (ctx->pk.type == PKEY_KEYTYPE_AES_192) ? CPACF_KMCTR_PAES_192 :
771 (ctx->pk.type == PKEY_KEYTYPE_AES_256) ?
772 CPACF_KMCTR_PAES_256 : 0;
773
774 /* Check if the function code is available */
775 ctx->fc = (fc && cpacf_test_func(&kmctr_functions, fc)) ? fc : 0;
776
777 return ctx->fc ? 0 : -EINVAL;
778 }
779
ctr_paes_set_key(struct crypto_skcipher * tfm,const u8 * in_key,unsigned int key_len)780 static int ctr_paes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
781 unsigned int key_len)
782 {
783 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
784 int rc;
785
786 _free_kb_keybuf(&ctx->kb);
787 rc = _key_to_kb(&ctx->kb, in_key, key_len);
788 if (rc)
789 return rc;
790
791 return __ctr_paes_set_key(ctx);
792 }
793
__ctrblk_init(u8 * ctrptr,u8 * iv,unsigned int nbytes)794 static unsigned int __ctrblk_init(u8 *ctrptr, u8 *iv, unsigned int nbytes)
795 {
796 unsigned int i, n;
797
798 /* only use complete blocks, max. PAGE_SIZE */
799 memcpy(ctrptr, iv, AES_BLOCK_SIZE);
800 n = (nbytes > PAGE_SIZE) ? PAGE_SIZE : nbytes & ~(AES_BLOCK_SIZE - 1);
801 for (i = (n / AES_BLOCK_SIZE) - 1; i > 0; i--) {
802 memcpy(ctrptr + AES_BLOCK_SIZE, ctrptr, AES_BLOCK_SIZE);
803 crypto_inc(ctrptr + AES_BLOCK_SIZE, AES_BLOCK_SIZE);
804 ctrptr += AES_BLOCK_SIZE;
805 }
806 return n;
807 }
808
ctr_paes_crypt(struct skcipher_request * req)809 static int ctr_paes_crypt(struct skcipher_request *req)
810 {
811 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
812 struct s390_paes_ctx *ctx = crypto_skcipher_ctx(tfm);
813 u8 buf[AES_BLOCK_SIZE], *ctrptr;
814 struct {
815 u8 key[PAES_256_PROTKEY_SIZE];
816 } param;
817 struct skcipher_walk walk;
818 unsigned int nbytes, n, k;
819 int rc, locked;
820
821 rc = skcipher_walk_virt(&walk, req, false);
822 if (rc)
823 return rc;
824
825 spin_lock_bh(&ctx->pk_lock);
826 memcpy(param.key, ctx->pk.protkey, PAES_256_PROTKEY_SIZE);
827 spin_unlock_bh(&ctx->pk_lock);
828
829 locked = mutex_trylock(&ctrblk_lock);
830
831 while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
832 n = AES_BLOCK_SIZE;
833 if (nbytes >= 2*AES_BLOCK_SIZE && locked)
834 n = __ctrblk_init(ctrblk, walk.iv, nbytes);
835 ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk.iv;
836 k = cpacf_kmctr(ctx->fc, ¶m, walk.dst.virt.addr,
837 walk.src.virt.addr, n, ctrptr);
838 if (k) {
839 if (ctrptr == ctrblk)
840 memcpy(walk.iv, ctrptr + k - AES_BLOCK_SIZE,
841 AES_BLOCK_SIZE);
842 crypto_inc(walk.iv, AES_BLOCK_SIZE);
843 rc = skcipher_walk_done(&walk, nbytes - k);
844 }
845 if (k < n) {
846 if (__paes_convert_key(ctx)) {
847 if (locked)
848 mutex_unlock(&ctrblk_lock);
849 return skcipher_walk_done(&walk, -EIO);
850 }
851 spin_lock_bh(&ctx->pk_lock);
852 memcpy(param.key, ctx->pk.protkey, PAES_256_PROTKEY_SIZE);
853 spin_unlock_bh(&ctx->pk_lock);
854 }
855 }
856 if (locked)
857 mutex_unlock(&ctrblk_lock);
858 /*
859 * final block may be < AES_BLOCK_SIZE, copy only nbytes
860 */
861 if (nbytes) {
862 memset(buf, 0, AES_BLOCK_SIZE);
863 memcpy(buf, walk.src.virt.addr, nbytes);
864 while (1) {
865 if (cpacf_kmctr(ctx->fc, ¶m, buf,
866 buf, AES_BLOCK_SIZE,
867 walk.iv) == AES_BLOCK_SIZE)
868 break;
869 if (__paes_convert_key(ctx))
870 return skcipher_walk_done(&walk, -EIO);
871 spin_lock_bh(&ctx->pk_lock);
872 memcpy(param.key, ctx->pk.protkey, PAES_256_PROTKEY_SIZE);
873 spin_unlock_bh(&ctx->pk_lock);
874 }
875 memcpy(walk.dst.virt.addr, buf, nbytes);
876 crypto_inc(walk.iv, AES_BLOCK_SIZE);
877 rc = skcipher_walk_done(&walk, nbytes);
878 }
879
880 return rc;
881 }
882
883 static struct skcipher_alg ctr_paes_alg = {
884 .base.cra_name = "ctr(paes)",
885 .base.cra_driver_name = "ctr-paes-s390",
886 .base.cra_priority = 402, /* ecb-paes-s390 + 1 */
887 .base.cra_blocksize = 1,
888 .base.cra_ctxsize = sizeof(struct s390_paes_ctx),
889 .base.cra_module = THIS_MODULE,
890 .base.cra_list = LIST_HEAD_INIT(ctr_paes_alg.base.cra_list),
891 .init = ctr_paes_init,
892 .exit = ctr_paes_exit,
893 .min_keysize = PAES_MIN_KEYSIZE,
894 .max_keysize = PAES_MAX_KEYSIZE,
895 .ivsize = AES_BLOCK_SIZE,
896 .setkey = ctr_paes_set_key,
897 .encrypt = ctr_paes_crypt,
898 .decrypt = ctr_paes_crypt,
899 .chunksize = AES_BLOCK_SIZE,
900 };
901
__crypto_unregister_skcipher(struct skcipher_alg * alg)902 static inline void __crypto_unregister_skcipher(struct skcipher_alg *alg)
903 {
904 if (!list_empty(&alg->base.cra_list))
905 crypto_unregister_skcipher(alg);
906 }
907
paes_s390_fini(void)908 static void paes_s390_fini(void)
909 {
910 __crypto_unregister_skcipher(&ctr_paes_alg);
911 __crypto_unregister_skcipher(&xts_paes_alg);
912 __crypto_unregister_skcipher(&cbc_paes_alg);
913 __crypto_unregister_skcipher(&ecb_paes_alg);
914 if (ctrblk)
915 free_page((unsigned long) ctrblk);
916 }
917
paes_s390_init(void)918 static int __init paes_s390_init(void)
919 {
920 int rc;
921
922 /* Query available functions for KM, KMC and KMCTR */
923 cpacf_query(CPACF_KM, &km_functions);
924 cpacf_query(CPACF_KMC, &kmc_functions);
925 cpacf_query(CPACF_KMCTR, &kmctr_functions);
926
927 if (cpacf_test_func(&km_functions, CPACF_KM_PAES_128) ||
928 cpacf_test_func(&km_functions, CPACF_KM_PAES_192) ||
929 cpacf_test_func(&km_functions, CPACF_KM_PAES_256)) {
930 rc = crypto_register_skcipher(&ecb_paes_alg);
931 if (rc)
932 goto out_err;
933 }
934
935 if (cpacf_test_func(&kmc_functions, CPACF_KMC_PAES_128) ||
936 cpacf_test_func(&kmc_functions, CPACF_KMC_PAES_192) ||
937 cpacf_test_func(&kmc_functions, CPACF_KMC_PAES_256)) {
938 rc = crypto_register_skcipher(&cbc_paes_alg);
939 if (rc)
940 goto out_err;
941 }
942
943 if (cpacf_test_func(&km_functions, CPACF_KM_PXTS_128) ||
944 cpacf_test_func(&km_functions, CPACF_KM_PXTS_256)) {
945 rc = crypto_register_skcipher(&xts_paes_alg);
946 if (rc)
947 goto out_err;
948 }
949
950 if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_PAES_128) ||
951 cpacf_test_func(&kmctr_functions, CPACF_KMCTR_PAES_192) ||
952 cpacf_test_func(&kmctr_functions, CPACF_KMCTR_PAES_256)) {
953 ctrblk = (u8 *) __get_free_page(GFP_KERNEL);
954 if (!ctrblk) {
955 rc = -ENOMEM;
956 goto out_err;
957 }
958 rc = crypto_register_skcipher(&ctr_paes_alg);
959 if (rc)
960 goto out_err;
961 }
962
963 return 0;
964 out_err:
965 paes_s390_fini();
966 return rc;
967 }
968
969 module_init(paes_s390_init);
970 module_exit(paes_s390_fini);
971
972 MODULE_ALIAS_CRYPTO("ecb(paes)");
973 MODULE_ALIAS_CRYPTO("cbc(paes)");
974 MODULE_ALIAS_CRYPTO("ctr(paes)");
975 MODULE_ALIAS_CRYPTO("xts(paes)");
976
977 MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm with protected keys");
978 MODULE_LICENSE("GPL");
979