1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * AES GCM 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/gcm.h>
14 #include <crypto/scatterwalk.h>
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <asm/vio.h>
18
19 #include "nx_csbcpb.h"
20 #include "nx.h"
21
22
gcm_aes_nx_set_key(struct crypto_aead * tfm,const u8 * in_key,unsigned int key_len)23 static int gcm_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_aead_ctx(tfm);
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 case AES_KEYSIZE_192:
40 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
41 NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_192);
42 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
43 break;
44 case AES_KEYSIZE_256:
45 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
46 NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_256);
47 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
48 break;
49 default:
50 return -EINVAL;
51 }
52
53 csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM;
54 memcpy(csbcpb->cpb.aes_gcm.key, in_key, key_len);
55
56 csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_GCA;
57 memcpy(csbcpb_aead->cpb.aes_gca.key, in_key, key_len);
58
59 return 0;
60 }
61
gcm4106_aes_nx_set_key(struct crypto_aead * tfm,const u8 * in_key,unsigned int key_len)62 static int gcm4106_aes_nx_set_key(struct crypto_aead *tfm,
63 const u8 *in_key,
64 unsigned int key_len)
65 {
66 struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(tfm);
67 char *nonce = nx_ctx->priv.gcm.nonce;
68 int rc;
69
70 if (key_len < 4)
71 return -EINVAL;
72
73 key_len -= 4;
74
75 rc = gcm_aes_nx_set_key(tfm, in_key, key_len);
76 if (rc)
77 goto out;
78
79 memcpy(nonce, in_key + key_len, 4);
80 out:
81 return rc;
82 }
83
gcm4106_aes_nx_setauthsize(struct crypto_aead * tfm,unsigned int authsize)84 static int gcm4106_aes_nx_setauthsize(struct crypto_aead *tfm,
85 unsigned int authsize)
86 {
87 switch (authsize) {
88 case 8:
89 case 12:
90 case 16:
91 break;
92 default:
93 return -EINVAL;
94 }
95
96 return 0;
97 }
98
nx_gca(struct nx_crypto_ctx * nx_ctx,struct aead_request * req,u8 * out,unsigned int assoclen)99 static int nx_gca(struct nx_crypto_ctx *nx_ctx,
100 struct aead_request *req,
101 u8 *out,
102 unsigned int assoclen)
103 {
104 int rc;
105 struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead;
106 struct scatter_walk walk;
107 struct nx_sg *nx_sg = nx_ctx->in_sg;
108 unsigned int nbytes = assoclen;
109 unsigned int processed = 0, to_process;
110 unsigned int max_sg_len;
111
112 if (nbytes <= AES_BLOCK_SIZE) {
113 scatterwalk_start(&walk, req->src);
114 scatterwalk_copychunks(out, &walk, nbytes, SCATTERWALK_FROM_SG);
115 scatterwalk_done(&walk, SCATTERWALK_FROM_SG, 0);
116 return 0;
117 }
118
119 NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_CONTINUATION;
120
121 /* page_limit: number of sg entries that fit on one page */
122 max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg),
123 nx_ctx->ap->sglen);
124 max_sg_len = min_t(u64, max_sg_len,
125 nx_ctx->ap->databytelen/NX_PAGE_SIZE);
126
127 do {
128 /*
129 * to_process: the data chunk to process in this update.
130 * This value is bound by sg list limits.
131 */
132 to_process = min_t(u64, nbytes - processed,
133 nx_ctx->ap->databytelen);
134 to_process = min_t(u64, to_process,
135 NX_PAGE_SIZE * (max_sg_len - 1));
136
137 nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len,
138 req->src, processed, &to_process);
139
140 if ((to_process + processed) < nbytes)
141 NX_CPB_FDM(csbcpb_aead) |= NX_FDM_INTERMEDIATE;
142 else
143 NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_INTERMEDIATE;
144
145 nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_sg)
146 * sizeof(struct nx_sg);
147
148 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead,
149 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
150 if (rc)
151 return rc;
152
153 memcpy(csbcpb_aead->cpb.aes_gca.in_pat,
154 csbcpb_aead->cpb.aes_gca.out_pat,
155 AES_BLOCK_SIZE);
156 NX_CPB_FDM(csbcpb_aead) |= NX_FDM_CONTINUATION;
157
158 atomic_inc(&(nx_ctx->stats->aes_ops));
159 atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes));
160
161 processed += to_process;
162 } while (processed < nbytes);
163
164 memcpy(out, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE);
165
166 return rc;
167 }
168
gmac(struct aead_request * req,const u8 * iv,unsigned int assoclen)169 static int gmac(struct aead_request *req, const u8 *iv, unsigned int assoclen)
170 {
171 int rc;
172 struct nx_crypto_ctx *nx_ctx =
173 crypto_aead_ctx(crypto_aead_reqtfm(req));
174 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
175 struct nx_sg *nx_sg;
176 unsigned int nbytes = assoclen;
177 unsigned int processed = 0, to_process;
178 unsigned int max_sg_len;
179
180 /* Set GMAC mode */
181 csbcpb->cpb.hdr.mode = NX_MODE_AES_GMAC;
182
183 NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION;
184
185 /* page_limit: number of sg entries that fit on one page */
186 max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg),
187 nx_ctx->ap->sglen);
188 max_sg_len = min_t(u64, max_sg_len,
189 nx_ctx->ap->databytelen/NX_PAGE_SIZE);
190
191 /* Copy IV */
192 memcpy(csbcpb->cpb.aes_gcm.iv_or_cnt, iv, AES_BLOCK_SIZE);
193
194 do {
195 /*
196 * to_process: the data chunk to process in this update.
197 * This value is bound by sg list limits.
198 */
199 to_process = min_t(u64, nbytes - processed,
200 nx_ctx->ap->databytelen);
201 to_process = min_t(u64, to_process,
202 NX_PAGE_SIZE * (max_sg_len - 1));
203
204 nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len,
205 req->src, processed, &to_process);
206
207 if ((to_process + processed) < nbytes)
208 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
209 else
210 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
211
212 nx_ctx->op.inlen = (nx_ctx->in_sg - nx_sg)
213 * sizeof(struct nx_sg);
214
215 csbcpb->cpb.aes_gcm.bit_length_data = 0;
216 csbcpb->cpb.aes_gcm.bit_length_aad = 8 * nbytes;
217
218 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
219 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
220 if (rc)
221 goto out;
222
223 memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad,
224 csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE);
225 memcpy(csbcpb->cpb.aes_gcm.in_s0,
226 csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE);
227
228 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
229
230 atomic_inc(&(nx_ctx->stats->aes_ops));
231 atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes));
232
233 processed += to_process;
234 } while (processed < nbytes);
235
236 out:
237 /* Restore GCM mode */
238 csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM;
239 return rc;
240 }
241
gcm_empty(struct aead_request * req,const u8 * iv,int enc)242 static int gcm_empty(struct aead_request *req, const u8 *iv, int enc)
243 {
244 int rc;
245 struct nx_crypto_ctx *nx_ctx =
246 crypto_aead_ctx(crypto_aead_reqtfm(req));
247 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
248 char out[AES_BLOCK_SIZE];
249 struct nx_sg *in_sg, *out_sg;
250 int len;
251
252 /* For scenarios where the input message is zero length, AES CTR mode
253 * may be used. Set the source data to be a single block (16B) of all
254 * zeros, and set the input IV value to be the same as the GMAC IV
255 * value. - nx_wb 4.8.1.3 */
256
257 /* Change to ECB mode */
258 csbcpb->cpb.hdr.mode = NX_MODE_AES_ECB;
259 memcpy(csbcpb->cpb.aes_ecb.key, csbcpb->cpb.aes_gcm.key,
260 sizeof(csbcpb->cpb.aes_ecb.key));
261 if (enc)
262 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
263 else
264 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
265
266 len = AES_BLOCK_SIZE;
267
268 /* Encrypt the counter/IV */
269 in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) iv,
270 &len, nx_ctx->ap->sglen);
271
272 if (len != AES_BLOCK_SIZE)
273 return -EINVAL;
274
275 len = sizeof(out);
276 out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *) out, &len,
277 nx_ctx->ap->sglen);
278
279 if (len != sizeof(out))
280 return -EINVAL;
281
282 nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
283 nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
284
285 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
286 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
287 if (rc)
288 goto out;
289 atomic_inc(&(nx_ctx->stats->aes_ops));
290
291 /* Copy out the auth tag */
292 memcpy(csbcpb->cpb.aes_gcm.out_pat_or_mac, out,
293 crypto_aead_authsize(crypto_aead_reqtfm(req)));
294 out:
295 /* Restore XCBC mode */
296 csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM;
297
298 /*
299 * ECB key uses the same region that GCM AAD and counter, so it's safe
300 * to just fill it with zeroes.
301 */
302 memset(csbcpb->cpb.aes_ecb.key, 0, sizeof(csbcpb->cpb.aes_ecb.key));
303
304 return rc;
305 }
306
gcm_aes_nx_crypt(struct aead_request * req,int enc,unsigned int assoclen)307 static int gcm_aes_nx_crypt(struct aead_request *req, int enc,
308 unsigned int assoclen)
309 {
310 struct nx_crypto_ctx *nx_ctx =
311 crypto_aead_ctx(crypto_aead_reqtfm(req));
312 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
313 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
314 unsigned int nbytes = req->cryptlen;
315 unsigned int processed = 0, to_process;
316 unsigned long irq_flags;
317 int rc = -EINVAL;
318
319 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
320
321 /* initialize the counter */
322 *(u32 *)&rctx->iv[NX_GCM_CTR_OFFSET] = 1;
323
324 if (nbytes == 0) {
325 if (assoclen == 0)
326 rc = gcm_empty(req, rctx->iv, enc);
327 else
328 rc = gmac(req, rctx->iv, assoclen);
329 if (rc)
330 goto out;
331 else
332 goto mac;
333 }
334
335 /* Process associated data */
336 csbcpb->cpb.aes_gcm.bit_length_aad = assoclen * 8;
337 if (assoclen) {
338 rc = nx_gca(nx_ctx, req, csbcpb->cpb.aes_gcm.in_pat_or_aad,
339 assoclen);
340 if (rc)
341 goto out;
342 }
343
344 /* Set flags for encryption */
345 NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION;
346 if (enc) {
347 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
348 } else {
349 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
350 nbytes -= crypto_aead_authsize(crypto_aead_reqtfm(req));
351 }
352
353 do {
354 to_process = nbytes - processed;
355
356 csbcpb->cpb.aes_gcm.bit_length_data = nbytes * 8;
357 rc = nx_build_sg_lists(nx_ctx, rctx->iv, req->dst,
358 req->src, &to_process,
359 processed + req->assoclen,
360 csbcpb->cpb.aes_gcm.iv_or_cnt);
361
362 if (rc)
363 goto out;
364
365 if ((to_process + processed) < nbytes)
366 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
367 else
368 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
369
370
371 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
372 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
373 if (rc)
374 goto out;
375
376 memcpy(rctx->iv, csbcpb->cpb.aes_gcm.out_cnt, AES_BLOCK_SIZE);
377 memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad,
378 csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE);
379 memcpy(csbcpb->cpb.aes_gcm.in_s0,
380 csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE);
381
382 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
383
384 atomic_inc(&(nx_ctx->stats->aes_ops));
385 atomic64_add(be32_to_cpu(csbcpb->csb.processed_byte_count),
386 &(nx_ctx->stats->aes_bytes));
387
388 processed += to_process;
389 } while (processed < nbytes);
390
391 mac:
392 if (enc) {
393 /* copy out the auth tag */
394 scatterwalk_map_and_copy(
395 csbcpb->cpb.aes_gcm.out_pat_or_mac,
396 req->dst, req->assoclen + nbytes,
397 crypto_aead_authsize(crypto_aead_reqtfm(req)),
398 SCATTERWALK_TO_SG);
399 } else {
400 u8 *itag = nx_ctx->priv.gcm.iauth_tag;
401 u8 *otag = csbcpb->cpb.aes_gcm.out_pat_or_mac;
402
403 scatterwalk_map_and_copy(
404 itag, req->src, req->assoclen + nbytes,
405 crypto_aead_authsize(crypto_aead_reqtfm(req)),
406 SCATTERWALK_FROM_SG);
407 rc = crypto_memneq(itag, otag,
408 crypto_aead_authsize(crypto_aead_reqtfm(req))) ?
409 -EBADMSG : 0;
410 }
411 out:
412 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
413 return rc;
414 }
415
gcm_aes_nx_encrypt(struct aead_request * req)416 static int gcm_aes_nx_encrypt(struct aead_request *req)
417 {
418 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
419 char *iv = rctx->iv;
420
421 memcpy(iv, req->iv, GCM_AES_IV_SIZE);
422
423 return gcm_aes_nx_crypt(req, 1, req->assoclen);
424 }
425
gcm_aes_nx_decrypt(struct aead_request * req)426 static int gcm_aes_nx_decrypt(struct aead_request *req)
427 {
428 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
429 char *iv = rctx->iv;
430
431 memcpy(iv, req->iv, GCM_AES_IV_SIZE);
432
433 return gcm_aes_nx_crypt(req, 0, req->assoclen);
434 }
435
gcm4106_aes_nx_encrypt(struct aead_request * req)436 static int gcm4106_aes_nx_encrypt(struct aead_request *req)
437 {
438 struct nx_crypto_ctx *nx_ctx =
439 crypto_aead_ctx(crypto_aead_reqtfm(req));
440 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
441 char *iv = rctx->iv;
442 char *nonce = nx_ctx->priv.gcm.nonce;
443
444 memcpy(iv, nonce, NX_GCM4106_NONCE_LEN);
445 memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8);
446
447 if (req->assoclen < 8)
448 return -EINVAL;
449
450 return gcm_aes_nx_crypt(req, 1, req->assoclen - 8);
451 }
452
gcm4106_aes_nx_decrypt(struct aead_request * req)453 static int gcm4106_aes_nx_decrypt(struct aead_request *req)
454 {
455 struct nx_crypto_ctx *nx_ctx =
456 crypto_aead_ctx(crypto_aead_reqtfm(req));
457 struct nx_gcm_rctx *rctx = aead_request_ctx(req);
458 char *iv = rctx->iv;
459 char *nonce = nx_ctx->priv.gcm.nonce;
460
461 memcpy(iv, nonce, NX_GCM4106_NONCE_LEN);
462 memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8);
463
464 if (req->assoclen < 8)
465 return -EINVAL;
466
467 return gcm_aes_nx_crypt(req, 0, req->assoclen - 8);
468 }
469
470 struct aead_alg nx_gcm_aes_alg = {
471 .base = {
472 .cra_name = "gcm(aes)",
473 .cra_driver_name = "gcm-aes-nx",
474 .cra_priority = 300,
475 .cra_blocksize = 1,
476 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
477 .cra_module = THIS_MODULE,
478 },
479 .init = nx_crypto_ctx_aes_gcm_init,
480 .exit = nx_crypto_ctx_aead_exit,
481 .ivsize = GCM_AES_IV_SIZE,
482 .maxauthsize = AES_BLOCK_SIZE,
483 .setkey = gcm_aes_nx_set_key,
484 .encrypt = gcm_aes_nx_encrypt,
485 .decrypt = gcm_aes_nx_decrypt,
486 };
487
488 struct aead_alg nx_gcm4106_aes_alg = {
489 .base = {
490 .cra_name = "rfc4106(gcm(aes))",
491 .cra_driver_name = "rfc4106-gcm-aes-nx",
492 .cra_priority = 300,
493 .cra_blocksize = 1,
494 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
495 .cra_module = THIS_MODULE,
496 },
497 .init = nx_crypto_ctx_aes_gcm_init,
498 .exit = nx_crypto_ctx_aead_exit,
499 .ivsize = GCM_RFC4106_IV_SIZE,
500 .maxauthsize = AES_BLOCK_SIZE,
501 .setkey = gcm4106_aes_nx_set_key,
502 .setauthsize = gcm4106_aes_nx_setauthsize,
503 .encrypt = gcm4106_aes_nx_encrypt,
504 .decrypt = gcm4106_aes_nx_decrypt,
505 };
506