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7#include <crypto/aes.h>
8#include <crypto/engine.h>
9#include <crypto/gcm.h>
10#include <crypto/internal/aead.h>
11#include <crypto/scatterwalk.h>
12
13#include <linux/dma-mapping.h>
14#include <linux/module.h>
15#include <linux/of_device.h>
16#include <linux/platform_device.h>
17
18#include <linux/firmware/xlnx-zynqmp.h>
19
20#define ZYNQMP_DMA_BIT_MASK 32U
21
22#define ZYNQMP_AES_KEY_SIZE AES_KEYSIZE_256
23#define ZYNQMP_AES_AUTH_SIZE 16U
24#define ZYNQMP_KEY_SRC_SEL_KEY_LEN 1U
25#define ZYNQMP_AES_BLK_SIZE 1U
26#define ZYNQMP_AES_MIN_INPUT_BLK_SIZE 4U
27#define ZYNQMP_AES_WORD_LEN 4U
28
29#define ZYNQMP_AES_GCM_TAG_MISMATCH_ERR 0x01
30#define ZYNQMP_AES_WRONG_KEY_SRC_ERR 0x13
31#define ZYNQMP_AES_PUF_NOT_PROGRAMMED 0xE300
32
33enum zynqmp_aead_op {
34 ZYNQMP_AES_DECRYPT = 0,
35 ZYNQMP_AES_ENCRYPT
36};
37
38enum zynqmp_aead_keysrc {
39 ZYNQMP_AES_KUP_KEY = 0,
40 ZYNQMP_AES_DEV_KEY,
41 ZYNQMP_AES_PUF_KEY
42};
43
44struct zynqmp_aead_drv_ctx {
45 union {
46 struct aead_alg aead;
47 } alg;
48 struct device *dev;
49 struct crypto_engine *engine;
50};
51
52struct zynqmp_aead_hw_req {
53 u64 src;
54 u64 iv;
55 u64 key;
56 u64 dst;
57 u64 size;
58 u64 op;
59 u64 keysrc;
60};
61
62struct zynqmp_aead_tfm_ctx {
63 struct crypto_engine_ctx engine_ctx;
64 struct device *dev;
65 u8 key[ZYNQMP_AES_KEY_SIZE];
66 u8 *iv;
67 u32 keylen;
68 u32 authsize;
69 enum zynqmp_aead_keysrc keysrc;
70 struct crypto_aead *fbk_cipher;
71};
72
73struct zynqmp_aead_req_ctx {
74 enum zynqmp_aead_op op;
75};
76
77static int zynqmp_aes_aead_cipher(struct aead_request *req)
78{
79 struct crypto_aead *aead = crypto_aead_reqtfm(req);
80 struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
81 struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
82 struct device *dev = tfm_ctx->dev;
83 struct zynqmp_aead_hw_req *hwreq;
84 dma_addr_t dma_addr_data, dma_addr_hw_req;
85 unsigned int data_size;
86 unsigned int status;
87 int ret;
88 size_t dma_size;
89 char *kbuf;
90 int err;
91
92 if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY)
93 dma_size = req->cryptlen + ZYNQMP_AES_KEY_SIZE
94 + GCM_AES_IV_SIZE;
95 else
96 dma_size = req->cryptlen + GCM_AES_IV_SIZE;
97
98 kbuf = dma_alloc_coherent(dev, dma_size, &dma_addr_data, GFP_KERNEL);
99 if (!kbuf)
100 return -ENOMEM;
101
102 hwreq = dma_alloc_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
103 &dma_addr_hw_req, GFP_KERNEL);
104 if (!hwreq) {
105 dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
106 return -ENOMEM;
107 }
108
109 data_size = req->cryptlen;
110 scatterwalk_map_and_copy(kbuf, req->src, 0, req->cryptlen, 0);
111 memcpy(kbuf + data_size, req->iv, GCM_AES_IV_SIZE);
112
113 hwreq->src = dma_addr_data;
114 hwreq->dst = dma_addr_data;
115 hwreq->iv = hwreq->src + data_size;
116 hwreq->keysrc = tfm_ctx->keysrc;
117 hwreq->op = rq_ctx->op;
118
119 if (hwreq->op == ZYNQMP_AES_ENCRYPT)
120 hwreq->size = data_size;
121 else
122 hwreq->size = data_size - ZYNQMP_AES_AUTH_SIZE;
123
124 if (hwreq->keysrc == ZYNQMP_AES_KUP_KEY) {
125 memcpy(kbuf + data_size + GCM_AES_IV_SIZE,
126 tfm_ctx->key, ZYNQMP_AES_KEY_SIZE);
127
128 hwreq->key = hwreq->src + data_size + GCM_AES_IV_SIZE;
129 } else {
130 hwreq->key = 0;
131 }
132
133 ret = zynqmp_pm_aes_engine(dma_addr_hw_req, &status);
134
135 if (ret) {
136 dev_err(dev, "ERROR: AES PM API failed\n");
137 err = ret;
138 } else if (status) {
139 switch (status) {
140 case ZYNQMP_AES_GCM_TAG_MISMATCH_ERR:
141 dev_err(dev, "ERROR: Gcm Tag mismatch\n");
142 break;
143 case ZYNQMP_AES_WRONG_KEY_SRC_ERR:
144 dev_err(dev, "ERROR: Wrong KeySrc, enable secure mode\n");
145 break;
146 case ZYNQMP_AES_PUF_NOT_PROGRAMMED:
147 dev_err(dev, "ERROR: PUF is not registered\n");
148 break;
149 default:
150 dev_err(dev, "ERROR: Unknown error\n");
151 break;
152 }
153 err = -status;
154 } else {
155 if (hwreq->op == ZYNQMP_AES_ENCRYPT)
156 data_size = data_size + ZYNQMP_AES_AUTH_SIZE;
157 else
158 data_size = data_size - ZYNQMP_AES_AUTH_SIZE;
159
160 sg_copy_from_buffer(req->dst, sg_nents(req->dst),
161 kbuf, data_size);
162 err = 0;
163 }
164
165 if (kbuf) {
166 memzero_explicit(kbuf, dma_size);
167 dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
168 }
169 if (hwreq) {
170 memzero_explicit(hwreq, sizeof(struct zynqmp_aead_hw_req));
171 dma_free_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
172 hwreq, dma_addr_hw_req);
173 }
174 return err;
175}
176
177static int zynqmp_fallback_check(struct zynqmp_aead_tfm_ctx *tfm_ctx,
178 struct aead_request *req)
179{
180 int need_fallback = 0;
181 struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
182
183 if (tfm_ctx->authsize != ZYNQMP_AES_AUTH_SIZE)
184 need_fallback = 1;
185
186 if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY &&
187 tfm_ctx->keylen != ZYNQMP_AES_KEY_SIZE) {
188 need_fallback = 1;
189 }
190 if (req->assoclen != 0 ||
191 req->cryptlen < ZYNQMP_AES_MIN_INPUT_BLK_SIZE) {
192 need_fallback = 1;
193 }
194 if ((req->cryptlen % ZYNQMP_AES_WORD_LEN) != 0)
195 need_fallback = 1;
196
197 if (rq_ctx->op == ZYNQMP_AES_DECRYPT &&
198 req->cryptlen <= ZYNQMP_AES_AUTH_SIZE) {
199 need_fallback = 1;
200 }
201 return need_fallback;
202}
203
204static int zynqmp_handle_aes_req(struct crypto_engine *engine,
205 void *req)
206{
207 struct aead_request *areq =
208 container_of(req, struct aead_request, base);
209 struct crypto_aead *aead = crypto_aead_reqtfm(req);
210 struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
211 struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(areq);
212 struct aead_request *subreq = aead_request_ctx(req);
213 int need_fallback;
214 int err;
215
216 need_fallback = zynqmp_fallback_check(tfm_ctx, areq);
217
218 if (need_fallback) {
219 aead_request_set_tfm(subreq, tfm_ctx->fbk_cipher);
220
221 aead_request_set_callback(subreq, areq->base.flags,
222 NULL, NULL);
223 aead_request_set_crypt(subreq, areq->src, areq->dst,
224 areq->cryptlen, areq->iv);
225 aead_request_set_ad(subreq, areq->assoclen);
226 if (rq_ctx->op == ZYNQMP_AES_ENCRYPT)
227 err = crypto_aead_encrypt(subreq);
228 else
229 err = crypto_aead_decrypt(subreq);
230 } else {
231 err = zynqmp_aes_aead_cipher(areq);
232 }
233
234 crypto_finalize_aead_request(engine, areq, err);
235 return 0;
236}
237
238static int zynqmp_aes_aead_setkey(struct crypto_aead *aead, const u8 *key,
239 unsigned int keylen)
240{
241 struct crypto_tfm *tfm = crypto_aead_tfm(aead);
242 struct zynqmp_aead_tfm_ctx *tfm_ctx =
243 (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
244 unsigned char keysrc;
245
246 if (keylen == ZYNQMP_KEY_SRC_SEL_KEY_LEN) {
247 keysrc = *key;
248 if (keysrc == ZYNQMP_AES_KUP_KEY ||
249 keysrc == ZYNQMP_AES_DEV_KEY ||
250 keysrc == ZYNQMP_AES_PUF_KEY) {
251 tfm_ctx->keysrc = (enum zynqmp_aead_keysrc)keysrc;
252 } else {
253 tfm_ctx->keylen = keylen;
254 }
255 } else {
256 tfm_ctx->keylen = keylen;
257 if (keylen == ZYNQMP_AES_KEY_SIZE) {
258 tfm_ctx->keysrc = ZYNQMP_AES_KUP_KEY;
259 memcpy(tfm_ctx->key, key, keylen);
260 }
261 }
262
263 tfm_ctx->fbk_cipher->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
264 tfm_ctx->fbk_cipher->base.crt_flags |= (aead->base.crt_flags &
265 CRYPTO_TFM_REQ_MASK);
266
267 return crypto_aead_setkey(tfm_ctx->fbk_cipher, key, keylen);
268}
269
270static int zynqmp_aes_aead_setauthsize(struct crypto_aead *aead,
271 unsigned int authsize)
272{
273 struct crypto_tfm *tfm = crypto_aead_tfm(aead);
274 struct zynqmp_aead_tfm_ctx *tfm_ctx =
275 (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
276
277 tfm_ctx->authsize = authsize;
278 return crypto_aead_setauthsize(tfm_ctx->fbk_cipher, authsize);
279}
280
281static int zynqmp_aes_aead_encrypt(struct aead_request *req)
282{
283 struct zynqmp_aead_drv_ctx *drv_ctx;
284 struct crypto_aead *aead = crypto_aead_reqtfm(req);
285 struct aead_alg *alg = crypto_aead_alg(aead);
286 struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
287
288 rq_ctx->op = ZYNQMP_AES_ENCRYPT;
289 drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead);
290
291 return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
292}
293
294static int zynqmp_aes_aead_decrypt(struct aead_request *req)
295{
296 struct zynqmp_aead_drv_ctx *drv_ctx;
297 struct crypto_aead *aead = crypto_aead_reqtfm(req);
298 struct aead_alg *alg = crypto_aead_alg(aead);
299 struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
300
301 rq_ctx->op = ZYNQMP_AES_DECRYPT;
302 drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead);
303
304 return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
305}
306
307static int zynqmp_aes_aead_init(struct crypto_aead *aead)
308{
309 struct crypto_tfm *tfm = crypto_aead_tfm(aead);
310 struct zynqmp_aead_tfm_ctx *tfm_ctx =
311 (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
312 struct zynqmp_aead_drv_ctx *drv_ctx;
313 struct aead_alg *alg = crypto_aead_alg(aead);
314
315 drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead);
316 tfm_ctx->dev = drv_ctx->dev;
317
318 tfm_ctx->engine_ctx.op.do_one_request = zynqmp_handle_aes_req;
319 tfm_ctx->engine_ctx.op.prepare_request = NULL;
320 tfm_ctx->engine_ctx.op.unprepare_request = NULL;
321
322 tfm_ctx->fbk_cipher = crypto_alloc_aead(drv_ctx->alg.aead.base.cra_name,
323 0,
324 CRYPTO_ALG_NEED_FALLBACK);
325
326 if (IS_ERR(tfm_ctx->fbk_cipher)) {
327 pr_err("%s() Error: failed to allocate fallback for %s\n",
328 __func__, drv_ctx->alg.aead.base.cra_name);
329 return PTR_ERR(tfm_ctx->fbk_cipher);
330 }
331
332 crypto_aead_set_reqsize(aead,
333 max(sizeof(struct zynqmp_aead_req_ctx),
334 sizeof(struct aead_request) +
335 crypto_aead_reqsize(tfm_ctx->fbk_cipher)));
336 return 0;
337}
338
339static void zynqmp_aes_aead_exit(struct crypto_aead *aead)
340{
341 struct crypto_tfm *tfm = crypto_aead_tfm(aead);
342 struct zynqmp_aead_tfm_ctx *tfm_ctx =
343 (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
344
345 if (tfm_ctx->fbk_cipher) {
346 crypto_free_aead(tfm_ctx->fbk_cipher);
347 tfm_ctx->fbk_cipher = NULL;
348 }
349 memzero_explicit(tfm_ctx, sizeof(struct zynqmp_aead_tfm_ctx));
350}
351
352static struct zynqmp_aead_drv_ctx aes_drv_ctx = {
353 .alg.aead = {
354 .setkey = zynqmp_aes_aead_setkey,
355 .setauthsize = zynqmp_aes_aead_setauthsize,
356 .encrypt = zynqmp_aes_aead_encrypt,
357 .decrypt = zynqmp_aes_aead_decrypt,
358 .init = zynqmp_aes_aead_init,
359 .exit = zynqmp_aes_aead_exit,
360 .ivsize = GCM_AES_IV_SIZE,
361 .maxauthsize = ZYNQMP_AES_AUTH_SIZE,
362 .base = {
363 .cra_name = "gcm(aes)",
364 .cra_driver_name = "xilinx-zynqmp-aes-gcm",
365 .cra_priority = 200,
366 .cra_flags = CRYPTO_ALG_TYPE_AEAD |
367 CRYPTO_ALG_ASYNC |
368 CRYPTO_ALG_ALLOCATES_MEMORY |
369 CRYPTO_ALG_KERN_DRIVER_ONLY |
370 CRYPTO_ALG_NEED_FALLBACK,
371 .cra_blocksize = ZYNQMP_AES_BLK_SIZE,
372 .cra_ctxsize = sizeof(struct zynqmp_aead_tfm_ctx),
373 .cra_module = THIS_MODULE,
374 }
375 }
376};
377
378static int zynqmp_aes_aead_probe(struct platform_device *pdev)
379{
380 struct device *dev = &pdev->dev;
381 int err;
382
383
384 if (!aes_drv_ctx.dev)
385 aes_drv_ctx.dev = dev;
386 else
387 return -ENODEV;
388
389 err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(ZYNQMP_DMA_BIT_MASK));
390 if (err < 0) {
391 dev_err(dev, "No usable DMA configuration\n");
392 return err;
393 }
394
395 aes_drv_ctx.engine = crypto_engine_alloc_init(dev, 1);
396 if (!aes_drv_ctx.engine) {
397 dev_err(dev, "Cannot alloc AES engine\n");
398 err = -ENOMEM;
399 goto err_engine;
400 }
401
402 err = crypto_engine_start(aes_drv_ctx.engine);
403 if (err) {
404 dev_err(dev, "Cannot start AES engine\n");
405 goto err_engine;
406 }
407
408 err = crypto_register_aead(&aes_drv_ctx.alg.aead);
409 if (err < 0) {
410 dev_err(dev, "Failed to register AEAD alg.\n");
411 goto err_aead;
412 }
413 return 0;
414
415err_aead:
416 crypto_unregister_aead(&aes_drv_ctx.alg.aead);
417
418err_engine:
419 if (aes_drv_ctx.engine)
420 crypto_engine_exit(aes_drv_ctx.engine);
421
422 return err;
423}
424
425static int zynqmp_aes_aead_remove(struct platform_device *pdev)
426{
427 crypto_engine_exit(aes_drv_ctx.engine);
428 crypto_unregister_aead(&aes_drv_ctx.alg.aead);
429
430 return 0;
431}
432
433static const struct of_device_id zynqmp_aes_dt_ids[] = {
434 { .compatible = "xlnx,zynqmp-aes" },
435 { }
436};
437MODULE_DEVICE_TABLE(of, zynqmp_aes_dt_ids);
438
439static struct platform_driver zynqmp_aes_driver = {
440 .probe = zynqmp_aes_aead_probe,
441 .remove = zynqmp_aes_aead_remove,
442 .driver = {
443 .name = "zynqmp-aes",
444 .of_match_table = zynqmp_aes_dt_ids,
445 },
446};
447
448module_platform_driver(zynqmp_aes_driver);
449MODULE_LICENSE("GPL");
450
