1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * AES CCM routines supporting the Power 7+ Nest Accelerators driver
4 *
5 * Copyright (C) 2012 International Business Machines Inc.
6 *
7 * Author: Kent Yoder <yoder1@us.ibm.com>
8 */
9
10 #include <crypto/internal/aead.h>
11 #include <crypto/aes.h>
12 #include <crypto/algapi.h>
13 #include <crypto/scatterwalk.h>
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/crypto.h>
17 #include <asm/vio.h>
18
19 #include "nx_csbcpb.h"
20 #include "nx.h"
21
22
ccm_aes_nx_set_key(struct crypto_aead * tfm,const u8 * in_key,unsigned int key_len)23 static int ccm_aes_nx_set_key(struct crypto_aead *tfm,
24 const u8 *in_key,
25 unsigned int key_len)
26 {
27 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);
28 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
29 struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead;
30
31 nx_ctx_init(nx_ctx, HCOP_FC_AES);
32
33 switch (key_len) {
34 case AES_KEYSIZE_128:
35 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
36 NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_128);
37 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
38 break;
39 default:
40 return -EINVAL;
41 }
42
43 csbcpb->cpb.hdr.mode = NX_MODE_AES_CCM;
44 memcpy(csbcpb->cpb.aes_ccm.key, in_key, key_len);
45
46 csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_CCA;
47 memcpy(csbcpb_aead->cpb.aes_cca.key, in_key, key_len);
48
49 return 0;
50
51 }
52
ccm4309_aes_nx_set_key(struct crypto_aead * tfm,const u8 * in_key,unsigned int key_len)53 static int ccm4309_aes_nx_set_key(struct crypto_aead *tfm,
54 const u8 *in_key,
55 unsigned int key_len)
56 {
57 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);
58
59 if (key_len < 3)
60 return -EINVAL;
61
62 key_len -= 3;
63
64 memcpy(nx_ctx->priv.ccm.nonce, in_key + key_len, 3);
65
66 return ccm_aes_nx_set_key(tfm, in_key, key_len);
67 }
68
ccm_aes_nx_setauthsize(struct crypto_aead * tfm,unsigned int authsize)69 static int ccm_aes_nx_setauthsize(struct crypto_aead *tfm,
70 unsigned int authsize)
71 {
72 switch (authsize) {
73 case 4:
74 case 6:
75 case 8:
76 case 10:
77 case 12:
78 case 14:
79 case 16:
80 break;
81 default:
82 return -EINVAL;
83 }
84
85 return 0;
86 }
87
ccm4309_aes_nx_setauthsize(struct crypto_aead * tfm,unsigned int authsize)88 static int ccm4309_aes_nx_setauthsize(struct crypto_aead *tfm,
89 unsigned int authsize)
90 {
91 switch (authsize) {
92 case 8:
93 case 12:
94 case 16:
95 break;
96 default:
97 return -EINVAL;
98 }
99
100 return 0;
101 }
102
103 /* taken from crypto/ccm.c */
set_msg_len(u8 * block,unsigned int msglen,int csize)104 static int set_msg_len(u8 *block, unsigned int msglen, int csize)
105 {
106 __be32 data;
107
108 memset(block, 0, csize);
109 block += csize;
110
111 if (csize >= 4)
112 csize = 4;
113 else if (msglen > (unsigned int)(1 << (8 * csize)))
114 return -EOVERFLOW;
115
116 data = cpu_to_be32(msglen);
117 memcpy(block - csize, (u8 *)&data + 4 - csize, csize);
118
119 return 0;
120 }
121
122 /* taken from crypto/ccm.c */
crypto_ccm_check_iv(const u8 * iv)123 static inline int crypto_ccm_check_iv(const u8 *iv)
124 {
125 /* 2 <= L <= 8, so 1 <= L' <= 7. */
126 if (1 > iv[0] || iv[0] > 7)
127 return -EINVAL;
128
129 return 0;
130 }
131
132 /* based on code from crypto/ccm.c */
generate_b0(u8 * iv,unsigned int assoclen,unsigned int authsize,unsigned int cryptlen,u8 * b0)133 static int generate_b0(u8 *iv, unsigned int assoclen, unsigned int authsize,
134 unsigned int cryptlen, u8 *b0)
135 {
136 unsigned int l, lp, m = authsize;
137
138 memcpy(b0, iv, 16);
139
140 lp = b0[0];
141 l = lp + 1;
142
143 /* set m, bits 3-5 */
144 *b0 |= (8 * ((m - 2) / 2));
145
146 /* set adata, bit 6, if associated data is used */
147 if (assoclen)
148 *b0 |= 64;
149
150 return set_msg_len(b0 + 16 - l, cryptlen, l);
151 }
152
generate_pat(u8 * iv,struct aead_request * req,struct nx_crypto_ctx * nx_ctx,unsigned int authsize,unsigned int nbytes,unsigned int assoclen,u8 * out)153 static int generate_pat(u8 *iv,
154 struct aead_request *req,
155 struct nx_crypto_ctx *nx_ctx,
156 unsigned int authsize,
157 unsigned int nbytes,
158 unsigned int assoclen,
159 u8 *out)
160 {
161 struct nx_sg *nx_insg = nx_ctx->in_sg;
162 struct nx_sg *nx_outsg = nx_ctx->out_sg;
163 unsigned int iauth_len = 0;
164 u8 tmp[16], *b1 = NULL, *b0 = NULL, *result = NULL;
165 int rc;
166 unsigned int max_sg_len;
167
168 /* zero the ctr value */
169 memset(iv + 15 - iv[0], 0, iv[0] + 1);
170
171 /* page 78 of nx_wb.pdf has,
172 * Note: RFC3610 allows the AAD data to be up to 2^64 -1 bytes
173 * in length. If a full message is used, the AES CCA implementation
174 * restricts the maximum AAD length to 2^32 -1 bytes.
175 * If partial messages are used, the implementation supports
176 * 2^64 -1 bytes maximum AAD length.
177 *
178 * However, in the cryptoapi's aead_request structure,
179 * assoclen is an unsigned int, thus it cannot hold a length
180 * value greater than 2^32 - 1.
181 * Thus the AAD is further constrained by this and is never
182 * greater than 2^32.
183 */
184
185 if (!assoclen) {
186 b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
187 } else if (assoclen <= 14) {
188 /* if associated data is 14 bytes or less, we do 1 GCM
189 * operation on 2 AES blocks, B0 (stored in the csbcpb) and B1,
190 * which is fed in through the source buffers here */
191 b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
192 b1 = nx_ctx->priv.ccm.iauth_tag;
193 iauth_len = assoclen;
194 } else if (assoclen <= 65280) {
195 /* if associated data is less than (2^16 - 2^8), we construct
196 * B1 differently and feed in the associated data to a CCA
197 * operation */
198 b0 = nx_ctx->csbcpb_aead->cpb.aes_cca.b0;
199 b1 = nx_ctx->csbcpb_aead->cpb.aes_cca.b1;
200 iauth_len = 14;
201 } else {
202 b0 = nx_ctx->csbcpb_aead->cpb.aes_cca.b0;
203 b1 = nx_ctx->csbcpb_aead->cpb.aes_cca.b1;
204 iauth_len = 10;
205 }
206
207 /* generate B0 */
208 rc = generate_b0(iv, assoclen, authsize, nbytes, b0);
209 if (rc)
210 return rc;
211
212 /* generate B1:
213 * add control info for associated data
214 * RFC 3610 and NIST Special Publication 800-38C
215 */
216 if (b1) {
217 memset(b1, 0, 16);
218 if (assoclen <= 65280) {
219 *(u16 *)b1 = assoclen;
220 scatterwalk_map_and_copy(b1 + 2, req->src, 0,
221 iauth_len, SCATTERWALK_FROM_SG);
222 } else {
223 *(u16 *)b1 = (u16)(0xfffe);
224 *(u32 *)&b1[2] = assoclen;
225 scatterwalk_map_and_copy(b1 + 6, req->src, 0,
226 iauth_len, SCATTERWALK_FROM_SG);
227 }
228 }
229
230 /* now copy any remaining AAD to scatterlist and call nx... */
231 if (!assoclen) {
232 return rc;
233 } else if (assoclen <= 14) {
234 unsigned int len = 16;
235
236 nx_insg = nx_build_sg_list(nx_insg, b1, &len, nx_ctx->ap->sglen);
237
238 if (len != 16)
239 return -EINVAL;
240
241 nx_outsg = nx_build_sg_list(nx_outsg, tmp, &len,
242 nx_ctx->ap->sglen);
243
244 if (len != 16)
245 return -EINVAL;
246
247 /* inlen should be negative, indicating to phyp that its a
248 * pointer to an sg list */
249 nx_ctx->op.inlen = (nx_ctx->in_sg - nx_insg) *
250 sizeof(struct nx_sg);
251 nx_ctx->op.outlen = (nx_ctx->out_sg - nx_outsg) *
252 sizeof(struct nx_sg);
253
254 NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_ENDE_ENCRYPT;
255 NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_INTERMEDIATE;
256
257 result = nx_ctx->csbcpb->cpb.aes_ccm.out_pat_or_mac;
258
259 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
260 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
261 if (rc)
262 return rc;
263
264 atomic_inc(&(nx_ctx->stats->aes_ops));
265 atomic64_add(assoclen, &nx_ctx->stats->aes_bytes);
266
267 } else {
268 unsigned int processed = 0, to_process;
269
270 processed += iauth_len;
271
272 /* page_limit: number of sg entries that fit on one page */
273 max_sg_len = min_t(u64, nx_ctx->ap->sglen,
274 nx_driver.of.max_sg_len/sizeof(struct nx_sg));
275 max_sg_len = min_t(u64, max_sg_len,
276 nx_ctx->ap->databytelen/NX_PAGE_SIZE);
277
278 do {
279 to_process = min_t(u32, assoclen - processed,
280 nx_ctx->ap->databytelen);
281
282 nx_insg = nx_walk_and_build(nx_ctx->in_sg,
283 nx_ctx->ap->sglen,
284 req->src, processed,
285 &to_process);
286
287 if ((to_process + processed) < assoclen) {
288 NX_CPB_FDM(nx_ctx->csbcpb_aead) |=
289 NX_FDM_INTERMEDIATE;
290 } else {
291 NX_CPB_FDM(nx_ctx->csbcpb_aead) &=
292 ~NX_FDM_INTERMEDIATE;
293 }
294
295
296 nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_insg) *
297 sizeof(struct nx_sg);
298
299 result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
300
301 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead,
302 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
303 if (rc)
304 return rc;
305
306 memcpy(nx_ctx->csbcpb_aead->cpb.aes_cca.b0,
307 nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0,
308 AES_BLOCK_SIZE);
309
310 NX_CPB_FDM(nx_ctx->csbcpb_aead) |= NX_FDM_CONTINUATION;
311
312 atomic_inc(&(nx_ctx->stats->aes_ops));
313 atomic64_add(assoclen, &nx_ctx->stats->aes_bytes);
314
315 processed += to_process;
316 } while (processed < assoclen);
317
318 result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
319 }
320
321 memcpy(out, result, AES_BLOCK_SIZE);
322
323 return rc;
324 }
325
ccm_nx_decrypt(struct aead_request * req,u8 * iv,unsigned int assoclen)326 static int ccm_nx_decrypt(struct aead_request *req,
327 u8 *iv,
328 unsigned int assoclen)
329 {
330 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
331 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
332 unsigned int nbytes = req->cryptlen;
333 unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
334 struct nx_ccm_priv *priv = &nx_ctx->priv.ccm;
335 unsigned long irq_flags;
336 unsigned int processed = 0, to_process;
337 int rc = -1;
338
339 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
340
341 nbytes -= authsize;
342
343 /* copy out the auth tag to compare with later */
344 scatterwalk_map_and_copy(priv->oauth_tag,
345 req->src, nbytes + req->assoclen, authsize,
346 SCATTERWALK_FROM_SG);
347
348 rc = generate_pat(iv, req, nx_ctx, authsize, nbytes, assoclen,
349 csbcpb->cpb.aes_ccm.in_pat_or_b0);
350 if (rc)
351 goto out;
352
353 do {
354
355 /* to_process: the AES_BLOCK_SIZE data chunk to process in this
356 * update. This value is bound by sg list limits.
357 */
358 to_process = nbytes - processed;
359
360 if ((to_process + processed) < nbytes)
361 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
362 else
363 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
364
365 NX_CPB_FDM(nx_ctx->csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
366
367 rc = nx_build_sg_lists(nx_ctx, iv, req->dst, req->src,
368 &to_process, processed + req->assoclen,
369 csbcpb->cpb.aes_ccm.iv_or_ctr);
370 if (rc)
371 goto out;
372
373 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
374 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
375 if (rc)
376 goto out;
377
378 /* for partial completion, copy following for next
379 * entry into loop...
380 */
381 memcpy(iv, csbcpb->cpb.aes_ccm.out_ctr, AES_BLOCK_SIZE);
382 memcpy(csbcpb->cpb.aes_ccm.in_pat_or_b0,
383 csbcpb->cpb.aes_ccm.out_pat_or_mac, AES_BLOCK_SIZE);
384 memcpy(csbcpb->cpb.aes_ccm.in_s0,
385 csbcpb->cpb.aes_ccm.out_s0, AES_BLOCK_SIZE);
386
387 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
388
389 /* update stats */
390 atomic_inc(&(nx_ctx->stats->aes_ops));
391 atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
392 &(nx_ctx->stats->aes_bytes));
393
394 processed += to_process;
395 } while (processed < nbytes);
396
397 rc = crypto_memneq(csbcpb->cpb.aes_ccm.out_pat_or_mac, priv->oauth_tag,
398 authsize) ? -EBADMSG : 0;
399 out:
400 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
401 return rc;
402 }
403
ccm_nx_encrypt(struct aead_request * req,u8 * iv,unsigned int assoclen)404 static int ccm_nx_encrypt(struct aead_request *req,
405 u8 *iv,
406 unsigned int assoclen)
407 {
408 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
409 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
410 unsigned int nbytes = req->cryptlen;
411 unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
412 unsigned long irq_flags;
413 unsigned int processed = 0, to_process;
414 int rc = -1;
415
416 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
417
418 rc = generate_pat(iv, req, nx_ctx, authsize, nbytes, assoclen,
419 csbcpb->cpb.aes_ccm.in_pat_or_b0);
420 if (rc)
421 goto out;
422
423 do {
424 /* to process: the AES_BLOCK_SIZE data chunk to process in this
425 * update. This value is bound by sg list limits.
426 */
427 to_process = nbytes - processed;
428
429 if ((to_process + processed) < nbytes)
430 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
431 else
432 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
433
434 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
435
436 rc = nx_build_sg_lists(nx_ctx, iv, req->dst, req->src,
437 &to_process, processed + req->assoclen,
438 csbcpb->cpb.aes_ccm.iv_or_ctr);
439 if (rc)
440 goto out;
441
442 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
443 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
444 if (rc)
445 goto out;
446
447 /* for partial completion, copy following for next
448 * entry into loop...
449 */
450 memcpy(iv, csbcpb->cpb.aes_ccm.out_ctr, AES_BLOCK_SIZE);
451 memcpy(csbcpb->cpb.aes_ccm.in_pat_or_b0,
452 csbcpb->cpb.aes_ccm.out_pat_or_mac, AES_BLOCK_SIZE);
453 memcpy(csbcpb->cpb.aes_ccm.in_s0,
454 csbcpb->cpb.aes_ccm.out_s0, AES_BLOCK_SIZE);
455
456 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
457
458 /* update stats */
459 atomic_inc(&(nx_ctx->stats->aes_ops));
460 atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
461 &(nx_ctx->stats->aes_bytes));
462
463 processed += to_process;
464
465 } while (processed < nbytes);
466
467 /* copy out the auth tag */
468 scatterwalk_map_and_copy(csbcpb->cpb.aes_ccm.out_pat_or_mac,
469 req->dst, nbytes + req->assoclen, authsize,
470 SCATTERWALK_TO_SG);
471
472 out:
473 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
474 return rc;
475 }
476
ccm4309_aes_nx_encrypt(struct aead_request * req)477 static int ccm4309_aes_nx_encrypt(struct aead_request *req)
478 {
479 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
480 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
481 u8 *iv = rctx->iv;
482
483 iv[0] = 3;
484 memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
485 memcpy(iv + 4, req->iv, 8);
486
487 return ccm_nx_encrypt(req, iv, req->assoclen - 8);
488 }
489
ccm_aes_nx_encrypt(struct aead_request * req)490 static int ccm_aes_nx_encrypt(struct aead_request *req)
491 {
492 int rc;
493
494 rc = crypto_ccm_check_iv(req->iv);
495 if (rc)
496 return rc;
497
498 return ccm_nx_encrypt(req, req->iv, req->assoclen);
499 }
500
ccm4309_aes_nx_decrypt(struct aead_request * req)501 static int ccm4309_aes_nx_decrypt(struct aead_request *req)
502 {
503 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
504 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
505 u8 *iv = rctx->iv;
506
507 iv[0] = 3;
508 memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
509 memcpy(iv + 4, req->iv, 8);
510
511 return ccm_nx_decrypt(req, iv, req->assoclen - 8);
512 }
513
ccm_aes_nx_decrypt(struct aead_request * req)514 static int ccm_aes_nx_decrypt(struct aead_request *req)
515 {
516 int rc;
517
518 rc = crypto_ccm_check_iv(req->iv);
519 if (rc)
520 return rc;
521
522 return ccm_nx_decrypt(req, req->iv, req->assoclen);
523 }
524
525 struct aead_alg nx_ccm_aes_alg = {
526 .base = {
527 .cra_name = "ccm(aes)",
528 .cra_driver_name = "ccm-aes-nx",
529 .cra_priority = 300,
530 .cra_flags = CRYPTO_ALG_NEED_FALLBACK,
531 .cra_blocksize = 1,
532 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
533 .cra_module = THIS_MODULE,
534 },
535 .init = nx_crypto_ctx_aes_ccm_init,
536 .exit = nx_crypto_ctx_aead_exit,
537 .ivsize = AES_BLOCK_SIZE,
538 .maxauthsize = AES_BLOCK_SIZE,
539 .setkey = ccm_aes_nx_set_key,
540 .setauthsize = ccm_aes_nx_setauthsize,
541 .encrypt = ccm_aes_nx_encrypt,
542 .decrypt = ccm_aes_nx_decrypt,
543 };
544
545 struct aead_alg nx_ccm4309_aes_alg = {
546 .base = {
547 .cra_name = "rfc4309(ccm(aes))",
548 .cra_driver_name = "rfc4309-ccm-aes-nx",
549 .cra_priority = 300,
550 .cra_flags = CRYPTO_ALG_NEED_FALLBACK,
551 .cra_blocksize = 1,
552 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
553 .cra_module = THIS_MODULE,
554 },
555 .init = nx_crypto_ctx_aes_ccm_init,
556 .exit = nx_crypto_ctx_aead_exit,
557 .ivsize = 8,
558 .maxauthsize = AES_BLOCK_SIZE,
559 .setkey = ccm4309_aes_nx_set_key,
560 .setauthsize = ccm4309_aes_nx_setauthsize,
561 .encrypt = ccm4309_aes_nx_encrypt,
562 .decrypt = ccm4309_aes_nx_decrypt,
563 };
564