xref: /openbmc/linux/drivers/crypto/qce/skcipher.c (revision 0bf49ffb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2010-2014, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/device.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/interrupt.h>
9 #include <linux/moduleparam.h>
10 #include <linux/types.h>
11 #include <crypto/aes.h>
12 #include <crypto/internal/des.h>
13 #include <crypto/internal/skcipher.h>
14 
15 #include "cipher.h"
16 
17 static unsigned int aes_sw_max_len = CONFIG_CRYPTO_DEV_QCE_SW_MAX_LEN;
18 module_param(aes_sw_max_len, uint, 0644);
19 MODULE_PARM_DESC(aes_sw_max_len,
20 		 "Only use hardware for AES requests larger than this "
21 		 "[0=always use hardware; anything <16 breaks AES-GCM; default="
22 		 __stringify(CONFIG_CRYPTO_DEV_QCE_SW_MAX_LEN)"]");
23 
24 static LIST_HEAD(skcipher_algs);
25 
26 static void qce_skcipher_done(void *data)
27 {
28 	struct crypto_async_request *async_req = data;
29 	struct skcipher_request *req = skcipher_request_cast(async_req);
30 	struct qce_cipher_reqctx *rctx = skcipher_request_ctx(req);
31 	struct qce_alg_template *tmpl = to_cipher_tmpl(crypto_skcipher_reqtfm(req));
32 	struct qce_device *qce = tmpl->qce;
33 	struct qce_result_dump *result_buf = qce->dma.result_buf;
34 	enum dma_data_direction dir_src, dir_dst;
35 	u32 status;
36 	int error;
37 	bool diff_dst;
38 
39 	diff_dst = (req->src != req->dst) ? true : false;
40 	dir_src = diff_dst ? DMA_TO_DEVICE : DMA_BIDIRECTIONAL;
41 	dir_dst = diff_dst ? DMA_FROM_DEVICE : DMA_BIDIRECTIONAL;
42 
43 	error = qce_dma_terminate_all(&qce->dma);
44 	if (error)
45 		dev_dbg(qce->dev, "skcipher dma termination error (%d)\n",
46 			error);
47 
48 	if (diff_dst)
49 		dma_unmap_sg(qce->dev, rctx->src_sg, rctx->src_nents, dir_src);
50 	dma_unmap_sg(qce->dev, rctx->dst_sg, rctx->dst_nents, dir_dst);
51 
52 	sg_free_table(&rctx->dst_tbl);
53 
54 	error = qce_check_status(qce, &status);
55 	if (error < 0)
56 		dev_dbg(qce->dev, "skcipher operation error (%x)\n", status);
57 
58 	memcpy(rctx->iv, result_buf->encr_cntr_iv, rctx->ivsize);
59 	qce->async_req_done(tmpl->qce, error);
60 }
61 
62 static int
63 qce_skcipher_async_req_handle(struct crypto_async_request *async_req)
64 {
65 	struct skcipher_request *req = skcipher_request_cast(async_req);
66 	struct qce_cipher_reqctx *rctx = skcipher_request_ctx(req);
67 	struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
68 	struct qce_alg_template *tmpl = to_cipher_tmpl(crypto_skcipher_reqtfm(req));
69 	struct qce_device *qce = tmpl->qce;
70 	enum dma_data_direction dir_src, dir_dst;
71 	struct scatterlist *sg;
72 	bool diff_dst;
73 	gfp_t gfp;
74 	int ret;
75 
76 	rctx->iv = req->iv;
77 	rctx->ivsize = crypto_skcipher_ivsize(skcipher);
78 	rctx->cryptlen = req->cryptlen;
79 
80 	diff_dst = (req->src != req->dst) ? true : false;
81 	dir_src = diff_dst ? DMA_TO_DEVICE : DMA_BIDIRECTIONAL;
82 	dir_dst = diff_dst ? DMA_FROM_DEVICE : DMA_BIDIRECTIONAL;
83 
84 	rctx->src_nents = sg_nents_for_len(req->src, req->cryptlen);
85 	if (diff_dst)
86 		rctx->dst_nents = sg_nents_for_len(req->dst, req->cryptlen);
87 	else
88 		rctx->dst_nents = rctx->src_nents;
89 	if (rctx->src_nents < 0) {
90 		dev_err(qce->dev, "Invalid numbers of src SG.\n");
91 		return rctx->src_nents;
92 	}
93 	if (rctx->dst_nents < 0) {
94 		dev_err(qce->dev, "Invalid numbers of dst SG.\n");
95 		return -rctx->dst_nents;
96 	}
97 
98 	rctx->dst_nents += 1;
99 
100 	gfp = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
101 						GFP_KERNEL : GFP_ATOMIC;
102 
103 	ret = sg_alloc_table(&rctx->dst_tbl, rctx->dst_nents, gfp);
104 	if (ret)
105 		return ret;
106 
107 	sg_init_one(&rctx->result_sg, qce->dma.result_buf, QCE_RESULT_BUF_SZ);
108 
109 	sg = qce_sgtable_add(&rctx->dst_tbl, req->dst, req->cryptlen);
110 	if (IS_ERR(sg)) {
111 		ret = PTR_ERR(sg);
112 		goto error_free;
113 	}
114 
115 	sg = qce_sgtable_add(&rctx->dst_tbl, &rctx->result_sg,
116 			     QCE_RESULT_BUF_SZ);
117 	if (IS_ERR(sg)) {
118 		ret = PTR_ERR(sg);
119 		goto error_free;
120 	}
121 
122 	sg_mark_end(sg);
123 	rctx->dst_sg = rctx->dst_tbl.sgl;
124 
125 	ret = dma_map_sg(qce->dev, rctx->dst_sg, rctx->dst_nents, dir_dst);
126 	if (ret < 0)
127 		goto error_free;
128 
129 	if (diff_dst) {
130 		ret = dma_map_sg(qce->dev, req->src, rctx->src_nents, dir_src);
131 		if (ret < 0)
132 			goto error_unmap_dst;
133 		rctx->src_sg = req->src;
134 	} else {
135 		rctx->src_sg = rctx->dst_sg;
136 	}
137 
138 	ret = qce_dma_prep_sgs(&qce->dma, rctx->src_sg, rctx->src_nents,
139 			       rctx->dst_sg, rctx->dst_nents,
140 			       qce_skcipher_done, async_req);
141 	if (ret)
142 		goto error_unmap_src;
143 
144 	qce_dma_issue_pending(&qce->dma);
145 
146 	ret = qce_start(async_req, tmpl->crypto_alg_type, req->cryptlen, 0);
147 	if (ret)
148 		goto error_terminate;
149 
150 	return 0;
151 
152 error_terminate:
153 	qce_dma_terminate_all(&qce->dma);
154 error_unmap_src:
155 	if (diff_dst)
156 		dma_unmap_sg(qce->dev, req->src, rctx->src_nents, dir_src);
157 error_unmap_dst:
158 	dma_unmap_sg(qce->dev, rctx->dst_sg, rctx->dst_nents, dir_dst);
159 error_free:
160 	sg_free_table(&rctx->dst_tbl);
161 	return ret;
162 }
163 
164 static int qce_skcipher_setkey(struct crypto_skcipher *ablk, const u8 *key,
165 				 unsigned int keylen)
166 {
167 	struct crypto_tfm *tfm = crypto_skcipher_tfm(ablk);
168 	struct qce_cipher_ctx *ctx = crypto_tfm_ctx(tfm);
169 	unsigned long flags = to_cipher_tmpl(ablk)->alg_flags;
170 	int ret;
171 
172 	if (!key || !keylen)
173 		return -EINVAL;
174 
175 	switch (IS_XTS(flags) ? keylen >> 1 : keylen) {
176 	case AES_KEYSIZE_128:
177 	case AES_KEYSIZE_256:
178 		memcpy(ctx->enc_key, key, keylen);
179 		break;
180 	}
181 
182 	ret = crypto_skcipher_setkey(ctx->fallback, key, keylen);
183 	if (!ret)
184 		ctx->enc_keylen = keylen;
185 	return ret;
186 }
187 
188 static int qce_des_setkey(struct crypto_skcipher *ablk, const u8 *key,
189 			  unsigned int keylen)
190 {
191 	struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(ablk);
192 	int err;
193 
194 	err = verify_skcipher_des_key(ablk, key);
195 	if (err)
196 		return err;
197 
198 	ctx->enc_keylen = keylen;
199 	memcpy(ctx->enc_key, key, keylen);
200 	return 0;
201 }
202 
203 static int qce_des3_setkey(struct crypto_skcipher *ablk, const u8 *key,
204 			   unsigned int keylen)
205 {
206 	struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(ablk);
207 	int err;
208 
209 	err = verify_skcipher_des3_key(ablk, key);
210 	if (err)
211 		return err;
212 
213 	ctx->enc_keylen = keylen;
214 	memcpy(ctx->enc_key, key, keylen);
215 	return 0;
216 }
217 
218 static int qce_skcipher_crypt(struct skcipher_request *req, int encrypt)
219 {
220 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
221 	struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);
222 	struct qce_cipher_reqctx *rctx = skcipher_request_ctx(req);
223 	struct qce_alg_template *tmpl = to_cipher_tmpl(tfm);
224 	int keylen;
225 	int ret;
226 
227 	rctx->flags = tmpl->alg_flags;
228 	rctx->flags |= encrypt ? QCE_ENCRYPT : QCE_DECRYPT;
229 	keylen = IS_XTS(rctx->flags) ? ctx->enc_keylen >> 1 : ctx->enc_keylen;
230 
231 	/* qce is hanging when AES-XTS request len > QCE_SECTOR_SIZE and
232 	 * is not a multiple of it; pass such requests to the fallback
233 	 */
234 	if (IS_AES(rctx->flags) &&
235 	    (((keylen != AES_KEYSIZE_128 && keylen != AES_KEYSIZE_256) ||
236 	      req->cryptlen <= aes_sw_max_len) ||
237 	     (IS_XTS(rctx->flags) && req->cryptlen > QCE_SECTOR_SIZE &&
238 	      req->cryptlen % QCE_SECTOR_SIZE))) {
239 		skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback);
240 		skcipher_request_set_callback(&rctx->fallback_req,
241 					      req->base.flags,
242 					      req->base.complete,
243 					      req->base.data);
244 		skcipher_request_set_crypt(&rctx->fallback_req, req->src,
245 					   req->dst, req->cryptlen, req->iv);
246 		ret = encrypt ? crypto_skcipher_encrypt(&rctx->fallback_req) :
247 				crypto_skcipher_decrypt(&rctx->fallback_req);
248 		return ret;
249 	}
250 
251 	return tmpl->qce->async_req_enqueue(tmpl->qce, &req->base);
252 }
253 
254 static int qce_skcipher_encrypt(struct skcipher_request *req)
255 {
256 	return qce_skcipher_crypt(req, 1);
257 }
258 
259 static int qce_skcipher_decrypt(struct skcipher_request *req)
260 {
261 	return qce_skcipher_crypt(req, 0);
262 }
263 
264 static int qce_skcipher_init(struct crypto_skcipher *tfm)
265 {
266 	/* take the size without the fallback skcipher_request at the end */
267 	crypto_skcipher_set_reqsize(tfm, offsetof(struct qce_cipher_reqctx,
268 						  fallback_req));
269 	return 0;
270 }
271 
272 static int qce_skcipher_init_fallback(struct crypto_skcipher *tfm)
273 {
274 	struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);
275 
276 	ctx->fallback = crypto_alloc_skcipher(crypto_tfm_alg_name(&tfm->base),
277 					      0, CRYPTO_ALG_NEED_FALLBACK);
278 	if (IS_ERR(ctx->fallback))
279 		return PTR_ERR(ctx->fallback);
280 
281 	crypto_skcipher_set_reqsize(tfm, sizeof(struct qce_cipher_reqctx) +
282 					 crypto_skcipher_reqsize(ctx->fallback));
283 	return 0;
284 }
285 
286 static void qce_skcipher_exit(struct crypto_skcipher *tfm)
287 {
288 	struct qce_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);
289 
290 	crypto_free_skcipher(ctx->fallback);
291 }
292 
293 struct qce_skcipher_def {
294 	unsigned long flags;
295 	const char *name;
296 	const char *drv_name;
297 	unsigned int blocksize;
298 	unsigned int chunksize;
299 	unsigned int ivsize;
300 	unsigned int min_keysize;
301 	unsigned int max_keysize;
302 };
303 
304 static const struct qce_skcipher_def skcipher_def[] = {
305 	{
306 		.flags		= QCE_ALG_AES | QCE_MODE_ECB,
307 		.name		= "ecb(aes)",
308 		.drv_name	= "ecb-aes-qce",
309 		.blocksize	= AES_BLOCK_SIZE,
310 		.ivsize		= AES_BLOCK_SIZE,
311 		.min_keysize	= AES_MIN_KEY_SIZE,
312 		.max_keysize	= AES_MAX_KEY_SIZE,
313 	},
314 	{
315 		.flags		= QCE_ALG_AES | QCE_MODE_CBC,
316 		.name		= "cbc(aes)",
317 		.drv_name	= "cbc-aes-qce",
318 		.blocksize	= AES_BLOCK_SIZE,
319 		.ivsize		= AES_BLOCK_SIZE,
320 		.min_keysize	= AES_MIN_KEY_SIZE,
321 		.max_keysize	= AES_MAX_KEY_SIZE,
322 	},
323 	{
324 		.flags		= QCE_ALG_AES | QCE_MODE_CTR,
325 		.name		= "ctr(aes)",
326 		.drv_name	= "ctr-aes-qce",
327 		.blocksize	= 1,
328 		.chunksize	= AES_BLOCK_SIZE,
329 		.ivsize		= AES_BLOCK_SIZE,
330 		.min_keysize	= AES_MIN_KEY_SIZE,
331 		.max_keysize	= AES_MAX_KEY_SIZE,
332 	},
333 	{
334 		.flags		= QCE_ALG_AES | QCE_MODE_XTS,
335 		.name		= "xts(aes)",
336 		.drv_name	= "xts-aes-qce",
337 		.blocksize	= AES_BLOCK_SIZE,
338 		.ivsize		= AES_BLOCK_SIZE,
339 		.min_keysize	= AES_MIN_KEY_SIZE * 2,
340 		.max_keysize	= AES_MAX_KEY_SIZE * 2,
341 	},
342 	{
343 		.flags		= QCE_ALG_DES | QCE_MODE_ECB,
344 		.name		= "ecb(des)",
345 		.drv_name	= "ecb-des-qce",
346 		.blocksize	= DES_BLOCK_SIZE,
347 		.ivsize		= 0,
348 		.min_keysize	= DES_KEY_SIZE,
349 		.max_keysize	= DES_KEY_SIZE,
350 	},
351 	{
352 		.flags		= QCE_ALG_DES | QCE_MODE_CBC,
353 		.name		= "cbc(des)",
354 		.drv_name	= "cbc-des-qce",
355 		.blocksize	= DES_BLOCK_SIZE,
356 		.ivsize		= DES_BLOCK_SIZE,
357 		.min_keysize	= DES_KEY_SIZE,
358 		.max_keysize	= DES_KEY_SIZE,
359 	},
360 	{
361 		.flags		= QCE_ALG_3DES | QCE_MODE_ECB,
362 		.name		= "ecb(des3_ede)",
363 		.drv_name	= "ecb-3des-qce",
364 		.blocksize	= DES3_EDE_BLOCK_SIZE,
365 		.ivsize		= 0,
366 		.min_keysize	= DES3_EDE_KEY_SIZE,
367 		.max_keysize	= DES3_EDE_KEY_SIZE,
368 	},
369 	{
370 		.flags		= QCE_ALG_3DES | QCE_MODE_CBC,
371 		.name		= "cbc(des3_ede)",
372 		.drv_name	= "cbc-3des-qce",
373 		.blocksize	= DES3_EDE_BLOCK_SIZE,
374 		.ivsize		= DES3_EDE_BLOCK_SIZE,
375 		.min_keysize	= DES3_EDE_KEY_SIZE,
376 		.max_keysize	= DES3_EDE_KEY_SIZE,
377 	},
378 };
379 
380 static int qce_skcipher_register_one(const struct qce_skcipher_def *def,
381 				       struct qce_device *qce)
382 {
383 	struct qce_alg_template *tmpl;
384 	struct skcipher_alg *alg;
385 	int ret;
386 
387 	tmpl = kzalloc(sizeof(*tmpl), GFP_KERNEL);
388 	if (!tmpl)
389 		return -ENOMEM;
390 
391 	alg = &tmpl->alg.skcipher;
392 
393 	snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
394 	snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
395 		 def->drv_name);
396 
397 	alg->base.cra_blocksize		= def->blocksize;
398 	alg->chunksize			= def->chunksize;
399 	alg->ivsize			= def->ivsize;
400 	alg->min_keysize		= def->min_keysize;
401 	alg->max_keysize		= def->max_keysize;
402 	alg->setkey			= IS_3DES(def->flags) ? qce_des3_setkey :
403 					  IS_DES(def->flags) ? qce_des_setkey :
404 					  qce_skcipher_setkey;
405 	alg->encrypt			= qce_skcipher_encrypt;
406 	alg->decrypt			= qce_skcipher_decrypt;
407 
408 	alg->base.cra_priority		= 300;
409 	alg->base.cra_flags		= CRYPTO_ALG_ASYNC |
410 					  CRYPTO_ALG_ALLOCATES_MEMORY |
411 					  CRYPTO_ALG_KERN_DRIVER_ONLY;
412 	alg->base.cra_ctxsize		= sizeof(struct qce_cipher_ctx);
413 	alg->base.cra_alignmask		= 0;
414 	alg->base.cra_module		= THIS_MODULE;
415 
416 	if (IS_AES(def->flags)) {
417 		alg->base.cra_flags    |= CRYPTO_ALG_NEED_FALLBACK;
418 		alg->init		= qce_skcipher_init_fallback;
419 		alg->exit		= qce_skcipher_exit;
420 	} else {
421 		alg->init		= qce_skcipher_init;
422 	}
423 
424 	INIT_LIST_HEAD(&tmpl->entry);
425 	tmpl->crypto_alg_type = CRYPTO_ALG_TYPE_SKCIPHER;
426 	tmpl->alg_flags = def->flags;
427 	tmpl->qce = qce;
428 
429 	ret = crypto_register_skcipher(alg);
430 	if (ret) {
431 		kfree(tmpl);
432 		dev_err(qce->dev, "%s registration failed\n", alg->base.cra_name);
433 		return ret;
434 	}
435 
436 	list_add_tail(&tmpl->entry, &skcipher_algs);
437 	dev_dbg(qce->dev, "%s is registered\n", alg->base.cra_name);
438 	return 0;
439 }
440 
441 static void qce_skcipher_unregister(struct qce_device *qce)
442 {
443 	struct qce_alg_template *tmpl, *n;
444 
445 	list_for_each_entry_safe(tmpl, n, &skcipher_algs, entry) {
446 		crypto_unregister_skcipher(&tmpl->alg.skcipher);
447 		list_del(&tmpl->entry);
448 		kfree(tmpl);
449 	}
450 }
451 
452 static int qce_skcipher_register(struct qce_device *qce)
453 {
454 	int ret, i;
455 
456 	for (i = 0; i < ARRAY_SIZE(skcipher_def); i++) {
457 		ret = qce_skcipher_register_one(&skcipher_def[i], qce);
458 		if (ret)
459 			goto err;
460 	}
461 
462 	return 0;
463 err:
464 	qce_skcipher_unregister(qce);
465 	return ret;
466 }
467 
468 const struct qce_algo_ops skcipher_ops = {
469 	.type = CRYPTO_ALG_TYPE_SKCIPHER,
470 	.register_algs = qce_skcipher_register,
471 	.unregister_algs = qce_skcipher_unregister,
472 	.async_req_handle = qce_skcipher_async_req_handle,
473 };
474