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
23static 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: &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
53static 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: &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
69static 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
88static 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 */
104static 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 */
123static 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 */
133static 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(block: b0 + 16 - l, msglen: cryptlen, csize: l);
151}
152
153static 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, cryptlen: 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 memcpy_from_sglist(buf: b1 + 2, sg: req->src, start: 0, nbytes: iauth_len);
221 } else {
222 *(u16 *)b1 = (u16)(0xfffe);
223 *(u32 *)&b1[2] = assoclen;
224 memcpy_from_sglist(buf: b1 + 6, sg: req->src, start: 0, nbytes: iauth_len);
225 }
226 }
227
228 /* now copy any remaining AAD to scatterlist and call nx... */
229 if (!assoclen) {
230 return rc;
231 } else if (assoclen <= 14) {
232 unsigned int len = 16;
233
234 nx_insg = nx_build_sg_list(nx_insg, b1, &len, nx_ctx->ap->sglen);
235
236 if (len != 16)
237 return -EINVAL;
238
239 nx_outsg = nx_build_sg_list(nx_outsg, tmp, &len,
240 nx_ctx->ap->sglen);
241
242 if (len != 16)
243 return -EINVAL;
244
245 /* inlen should be negative, indicating to phyp that its a
246 * pointer to an sg list */
247 nx_ctx->op.inlen = (nx_ctx->in_sg - nx_insg) *
248 sizeof(struct nx_sg);
249 nx_ctx->op.outlen = (nx_ctx->out_sg - nx_outsg) *
250 sizeof(struct nx_sg);
251
252 NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_ENDE_ENCRYPT;
253 NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_INTERMEDIATE;
254
255 result = nx_ctx->csbcpb->cpb.aes_ccm.out_pat_or_mac;
256
257 rc = nx_hcall_sync(ctx: nx_ctx, op: &nx_ctx->op,
258 may_sleep: req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
259 if (rc)
260 return rc;
261
262 atomic_inc(v: &(nx_ctx->stats->aes_ops));
263 atomic64_add(i: assoclen, v: &nx_ctx->stats->aes_bytes);
264
265 } else {
266 unsigned int processed = 0, to_process;
267
268 processed += iauth_len;
269
270 /* page_limit: number of sg entries that fit on one page */
271 max_sg_len = min_t(u64, nx_ctx->ap->sglen,
272 nx_driver.of.max_sg_len/sizeof(struct nx_sg));
273 max_sg_len = min_t(u64, max_sg_len,
274 nx_ctx->ap->databytelen/NX_PAGE_SIZE);
275
276 do {
277 to_process = min_t(u32, assoclen - processed,
278 nx_ctx->ap->databytelen);
279
280 nx_insg = nx_walk_and_build(nx_ctx->in_sg,
281 nx_ctx->ap->sglen,
282 req->src, processed,
283 &to_process);
284
285 if ((to_process + processed) < assoclen) {
286 NX_CPB_FDM(nx_ctx->csbcpb_aead) |=
287 NX_FDM_INTERMEDIATE;
288 } else {
289 NX_CPB_FDM(nx_ctx->csbcpb_aead) &=
290 ~NX_FDM_INTERMEDIATE;
291 }
292
293
294 nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_insg) *
295 sizeof(struct nx_sg);
296
297 result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
298
299 rc = nx_hcall_sync(ctx: nx_ctx, op: &nx_ctx->op_aead,
300 may_sleep: req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
301 if (rc)
302 return rc;
303
304 memcpy(nx_ctx->csbcpb_aead->cpb.aes_cca.b0,
305 nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0,
306 AES_BLOCK_SIZE);
307
308 NX_CPB_FDM(nx_ctx->csbcpb_aead) |= NX_FDM_CONTINUATION;
309
310 atomic_inc(v: &(nx_ctx->stats->aes_ops));
311 atomic64_add(i: assoclen, v: &nx_ctx->stats->aes_bytes);
312
313 processed += to_process;
314 } while (processed < assoclen);
315
316 result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
317 }
318
319 memcpy(out, result, AES_BLOCK_SIZE);
320
321 return rc;
322}
323
324static int ccm_nx_decrypt(struct aead_request *req,
325 u8 *iv,
326 unsigned int assoclen)
327{
328 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm: req->base.tfm);
329 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
330 unsigned int nbytes = req->cryptlen;
331 unsigned int authsize = crypto_aead_authsize(tfm: crypto_aead_reqtfm(req));
332 struct nx_ccm_priv *priv = &nx_ctx->priv.ccm;
333 unsigned long irq_flags;
334 unsigned int processed = 0, to_process;
335 int rc = -1;
336
337 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
338
339 nbytes -= authsize;
340
341 /* copy out the auth tag to compare with later */
342 memcpy_from_sglist(buf: priv->oauth_tag, sg: req->src, start: nbytes + req->assoclen,
343 nbytes: authsize);
344
345 rc = generate_pat(iv, req, nx_ctx, authsize, nbytes, assoclen,
346 out: csbcpb->cpb.aes_ccm.in_pat_or_b0);
347 if (rc)
348 goto out;
349
350 do {
351
352 /* to_process: the AES_BLOCK_SIZE data chunk to process in this
353 * update. This value is bound by sg list limits.
354 */
355 to_process = nbytes - processed;
356
357 if ((to_process + processed) < nbytes)
358 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
359 else
360 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
361
362 NX_CPB_FDM(nx_ctx->csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
363
364 rc = nx_build_sg_lists(nx_ctx, iv, dst: req->dst, src: req->src,
365 nbytes: &to_process, offset: processed + req->assoclen,
366 oiv: csbcpb->cpb.aes_ccm.iv_or_ctr);
367 if (rc)
368 goto out;
369
370 rc = nx_hcall_sync(ctx: nx_ctx, op: &nx_ctx->op,
371 may_sleep: req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
372 if (rc)
373 goto out;
374
375 /* for partial completion, copy following for next
376 * entry into loop...
377 */
378 memcpy(iv, csbcpb->cpb.aes_ccm.out_ctr, AES_BLOCK_SIZE);
379 memcpy(csbcpb->cpb.aes_ccm.in_pat_or_b0,
380 csbcpb->cpb.aes_ccm.out_pat_or_mac, AES_BLOCK_SIZE);
381 memcpy(csbcpb->cpb.aes_ccm.in_s0,
382 csbcpb->cpb.aes_ccm.out_s0, AES_BLOCK_SIZE);
383
384 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
385
386 /* update stats */
387 atomic_inc(v: &(nx_ctx->stats->aes_ops));
388 atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
389 v: &(nx_ctx->stats->aes_bytes));
390
391 processed += to_process;
392 } while (processed < nbytes);
393
394 rc = crypto_memneq(a: csbcpb->cpb.aes_ccm.out_pat_or_mac, b: priv->oauth_tag,
395 size: authsize) ? -EBADMSG : 0;
396out:
397 spin_unlock_irqrestore(lock: &nx_ctx->lock, flags: irq_flags);
398 return rc;
399}
400
401static int ccm_nx_encrypt(struct aead_request *req,
402 u8 *iv,
403 unsigned int assoclen)
404{
405 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm: req->base.tfm);
406 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
407 unsigned int nbytes = req->cryptlen;
408 unsigned int authsize = crypto_aead_authsize(tfm: crypto_aead_reqtfm(req));
409 unsigned long irq_flags;
410 unsigned int processed = 0, to_process;
411 int rc = -1;
412
413 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
414
415 rc = generate_pat(iv, req, nx_ctx, authsize, nbytes, assoclen,
416 out: csbcpb->cpb.aes_ccm.in_pat_or_b0);
417 if (rc)
418 goto out;
419
420 do {
421 /* to process: the AES_BLOCK_SIZE data chunk to process in this
422 * update. This value is bound by sg list limits.
423 */
424 to_process = nbytes - processed;
425
426 if ((to_process + processed) < nbytes)
427 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
428 else
429 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
430
431 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
432
433 rc = nx_build_sg_lists(nx_ctx, iv, dst: req->dst, src: req->src,
434 nbytes: &to_process, offset: processed + req->assoclen,
435 oiv: csbcpb->cpb.aes_ccm.iv_or_ctr);
436 if (rc)
437 goto out;
438
439 rc = nx_hcall_sync(ctx: nx_ctx, op: &nx_ctx->op,
440 may_sleep: req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
441 if (rc)
442 goto out;
443
444 /* for partial completion, copy following for next
445 * entry into loop...
446 */
447 memcpy(iv, csbcpb->cpb.aes_ccm.out_ctr, AES_BLOCK_SIZE);
448 memcpy(csbcpb->cpb.aes_ccm.in_pat_or_b0,
449 csbcpb->cpb.aes_ccm.out_pat_or_mac, AES_BLOCK_SIZE);
450 memcpy(csbcpb->cpb.aes_ccm.in_s0,
451 csbcpb->cpb.aes_ccm.out_s0, AES_BLOCK_SIZE);
452
453 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
454
455 /* update stats */
456 atomic_inc(v: &(nx_ctx->stats->aes_ops));
457 atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
458 v: &(nx_ctx->stats->aes_bytes));
459
460 processed += to_process;
461
462 } while (processed < nbytes);
463
464 /* copy out the auth tag */
465 memcpy_to_sglist(sg: req->dst, start: nbytes + req->assoclen,
466 buf: csbcpb->cpb.aes_ccm.out_pat_or_mac, nbytes: authsize);
467
468out:
469 spin_unlock_irqrestore(lock: &nx_ctx->lock, flags: irq_flags);
470 return rc;
471}
472
473static int ccm4309_aes_nx_encrypt(struct aead_request *req)
474{
475 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm: req->base.tfm);
476 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
477 u8 *iv = rctx->iv;
478
479 iv[0] = 3;
480 memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
481 memcpy(iv + 4, req->iv, 8);
482
483 return ccm_nx_encrypt(req, iv, assoclen: req->assoclen - 8);
484}
485
486static int ccm_aes_nx_encrypt(struct aead_request *req)
487{
488 int rc;
489
490 rc = crypto_ccm_check_iv(iv: req->iv);
491 if (rc)
492 return rc;
493
494 return ccm_nx_encrypt(req, iv: req->iv, assoclen: req->assoclen);
495}
496
497static int ccm4309_aes_nx_decrypt(struct aead_request *req)
498{
499 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm: req->base.tfm);
500 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
501 u8 *iv = rctx->iv;
502
503 iv[0] = 3;
504 memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
505 memcpy(iv + 4, req->iv, 8);
506
507 return ccm_nx_decrypt(req, iv, assoclen: req->assoclen - 8);
508}
509
510static int ccm_aes_nx_decrypt(struct aead_request *req)
511{
512 int rc;
513
514 rc = crypto_ccm_check_iv(iv: req->iv);
515 if (rc)
516 return rc;
517
518 return ccm_nx_decrypt(req, iv: req->iv, assoclen: req->assoclen);
519}
520
521struct aead_alg nx_ccm_aes_alg = {
522 .base = {
523 .cra_name = "ccm(aes)",
524 .cra_driver_name = "ccm-aes-nx",
525 .cra_priority = 300,
526 .cra_flags = CRYPTO_ALG_NEED_FALLBACK,
527 .cra_blocksize = 1,
528 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
529 .cra_module = THIS_MODULE,
530 },
531 .init = nx_crypto_ctx_aes_ccm_init,
532 .exit = nx_crypto_ctx_aead_exit,
533 .ivsize = AES_BLOCK_SIZE,
534 .maxauthsize = AES_BLOCK_SIZE,
535 .setkey = ccm_aes_nx_set_key,
536 .setauthsize = ccm_aes_nx_setauthsize,
537 .encrypt = ccm_aes_nx_encrypt,
538 .decrypt = ccm_aes_nx_decrypt,
539};
540
541struct aead_alg nx_ccm4309_aes_alg = {
542 .base = {
543 .cra_name = "rfc4309(ccm(aes))",
544 .cra_driver_name = "rfc4309-ccm-aes-nx",
545 .cra_priority = 300,
546 .cra_flags = CRYPTO_ALG_NEED_FALLBACK,
547 .cra_blocksize = 1,
548 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
549 .cra_module = THIS_MODULE,
550 },
551 .init = nx_crypto_ctx_aes_ccm_init,
552 .exit = nx_crypto_ctx_aead_exit,
553 .ivsize = 8,
554 .maxauthsize = AES_BLOCK_SIZE,
555 .setkey = ccm4309_aes_nx_set_key,
556 .setauthsize = ccm4309_aes_nx_setauthsize,
557 .encrypt = ccm4309_aes_nx_encrypt,
558 .decrypt = ccm4309_aes_nx_decrypt,
559};
560

source code of linux/drivers/crypto/nx/nx-aes-ccm.c