1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Xilinx ZynqMP SHA Driver.
4  * Copyright (c) 2022 Xilinx Inc.
5  */
6 #include <linux/cacheflush.h>
7 #include <crypto/hash.h>
8 #include <crypto/internal/hash.h>
9 #include <crypto/sha3.h>
10 #include <linux/crypto.h>
11 #include <linux/device.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/firmware/xlnx-zynqmp.h>
14 #include <linux/init.h>
15 #include <linux/io.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 
20 #define ZYNQMP_DMA_BIT_MASK		32U
21 #define ZYNQMP_DMA_ALLOC_FIXED_SIZE	0x1000U
22 
23 enum zynqmp_sha_op {
24 	ZYNQMP_SHA3_INIT = 1,
25 	ZYNQMP_SHA3_UPDATE = 2,
26 	ZYNQMP_SHA3_FINAL = 4,
27 };
28 
29 struct zynqmp_sha_drv_ctx {
30 	struct shash_alg sha3_384;
31 	struct device *dev;
32 };
33 
34 struct zynqmp_sha_tfm_ctx {
35 	struct device *dev;
36 	struct crypto_shash *fbk_tfm;
37 };
38 
39 struct zynqmp_sha_desc_ctx {
40 	struct shash_desc fbk_req;
41 };
42 
43 static dma_addr_t update_dma_addr, final_dma_addr;
44 static char *ubuf, *fbuf;
45 
46 static int zynqmp_sha_init_tfm(struct crypto_shash *hash)
47 {
48 	const char *fallback_driver_name = crypto_shash_alg_name(hash);
49 	struct zynqmp_sha_tfm_ctx *tfm_ctx = crypto_shash_ctx(hash);
50 	struct shash_alg *alg = crypto_shash_alg(hash);
51 	struct crypto_shash *fallback_tfm;
52 	struct zynqmp_sha_drv_ctx *drv_ctx;
53 
54 	drv_ctx = container_of(alg, struct zynqmp_sha_drv_ctx, sha3_384);
55 	tfm_ctx->dev = drv_ctx->dev;
56 
57 	/* Allocate a fallback and abort if it failed. */
58 	fallback_tfm = crypto_alloc_shash(fallback_driver_name, 0,
59 					  CRYPTO_ALG_NEED_FALLBACK);
60 	if (IS_ERR(fallback_tfm))
61 		return PTR_ERR(fallback_tfm);
62 
63 	tfm_ctx->fbk_tfm = fallback_tfm;
64 	hash->descsize += crypto_shash_descsize(tfm_ctx->fbk_tfm);
65 
66 	return 0;
67 }
68 
69 static void zynqmp_sha_exit_tfm(struct crypto_shash *hash)
70 {
71 	struct zynqmp_sha_tfm_ctx *tfm_ctx = crypto_shash_ctx(hash);
72 
73 	if (tfm_ctx->fbk_tfm) {
74 		crypto_free_shash(tfm_ctx->fbk_tfm);
75 		tfm_ctx->fbk_tfm = NULL;
76 	}
77 
78 	memzero_explicit(tfm_ctx, sizeof(struct zynqmp_sha_tfm_ctx));
79 }
80 
81 static int zynqmp_sha_init(struct shash_desc *desc)
82 {
83 	struct zynqmp_sha_desc_ctx *dctx = shash_desc_ctx(desc);
84 	struct zynqmp_sha_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
85 
86 	dctx->fbk_req.tfm = tctx->fbk_tfm;
87 	return crypto_shash_init(&dctx->fbk_req);
88 }
89 
90 static int zynqmp_sha_update(struct shash_desc *desc, const u8 *data, unsigned int length)
91 {
92 	struct zynqmp_sha_desc_ctx *dctx = shash_desc_ctx(desc);
93 
94 	return crypto_shash_update(&dctx->fbk_req, data, length);
95 }
96 
97 static int zynqmp_sha_final(struct shash_desc *desc, u8 *out)
98 {
99 	struct zynqmp_sha_desc_ctx *dctx = shash_desc_ctx(desc);
100 
101 	return crypto_shash_final(&dctx->fbk_req, out);
102 }
103 
104 static int zynqmp_sha_finup(struct shash_desc *desc, const u8 *data, unsigned int length, u8 *out)
105 {
106 	struct zynqmp_sha_desc_ctx *dctx = shash_desc_ctx(desc);
107 
108 	return crypto_shash_finup(&dctx->fbk_req, data, length, out);
109 }
110 
111 static int zynqmp_sha_import(struct shash_desc *desc, const void *in)
112 {
113 	struct zynqmp_sha_desc_ctx *dctx = shash_desc_ctx(desc);
114 	struct zynqmp_sha_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
115 
116 	dctx->fbk_req.tfm = tctx->fbk_tfm;
117 	return crypto_shash_import(&dctx->fbk_req, in);
118 }
119 
120 static int zynqmp_sha_export(struct shash_desc *desc, void *out)
121 {
122 	struct zynqmp_sha_desc_ctx *dctx = shash_desc_ctx(desc);
123 
124 	return crypto_shash_export(&dctx->fbk_req, out);
125 }
126 
127 static int zynqmp_sha_digest(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out)
128 {
129 	unsigned int remaining_len = len;
130 	int update_size;
131 	int ret;
132 
133 	ret = zynqmp_pm_sha_hash(0, 0, ZYNQMP_SHA3_INIT);
134 	if (ret)
135 		return ret;
136 
137 	while (remaining_len != 0) {
138 		memzero_explicit(ubuf, ZYNQMP_DMA_ALLOC_FIXED_SIZE);
139 		if (remaining_len >= ZYNQMP_DMA_ALLOC_FIXED_SIZE) {
140 			update_size = ZYNQMP_DMA_ALLOC_FIXED_SIZE;
141 			remaining_len -= ZYNQMP_DMA_ALLOC_FIXED_SIZE;
142 		} else {
143 			update_size = remaining_len;
144 			remaining_len = 0;
145 		}
146 		memcpy(ubuf, data, update_size);
147 		flush_icache_range((unsigned long)ubuf, (unsigned long)ubuf + update_size);
148 		ret = zynqmp_pm_sha_hash(update_dma_addr, update_size, ZYNQMP_SHA3_UPDATE);
149 		if (ret)
150 			return ret;
151 
152 		data += update_size;
153 	}
154 
155 	ret = zynqmp_pm_sha_hash(final_dma_addr, SHA3_384_DIGEST_SIZE, ZYNQMP_SHA3_FINAL);
156 	memcpy(out, fbuf, SHA3_384_DIGEST_SIZE);
157 	memzero_explicit(fbuf, SHA3_384_DIGEST_SIZE);
158 
159 	return ret;
160 }
161 
162 static struct zynqmp_sha_drv_ctx sha3_drv_ctx = {
163 	.sha3_384 = {
164 		.init = zynqmp_sha_init,
165 		.update = zynqmp_sha_update,
166 		.final = zynqmp_sha_final,
167 		.finup = zynqmp_sha_finup,
168 		.digest = zynqmp_sha_digest,
169 		.export = zynqmp_sha_export,
170 		.import = zynqmp_sha_import,
171 		.init_tfm = zynqmp_sha_init_tfm,
172 		.exit_tfm = zynqmp_sha_exit_tfm,
173 		.descsize = sizeof(struct zynqmp_sha_desc_ctx),
174 		.statesize = sizeof(struct sha3_state),
175 		.digestsize = SHA3_384_DIGEST_SIZE,
176 		.base = {
177 			.cra_name = "sha3-384",
178 			.cra_driver_name = "zynqmp-sha3-384",
179 			.cra_priority = 300,
180 			.cra_flags = CRYPTO_ALG_KERN_DRIVER_ONLY |
181 				     CRYPTO_ALG_ALLOCATES_MEMORY |
182 				     CRYPTO_ALG_NEED_FALLBACK,
183 			.cra_blocksize = SHA3_384_BLOCK_SIZE,
184 			.cra_ctxsize = sizeof(struct zynqmp_sha_tfm_ctx),
185 			.cra_alignmask = 3,
186 			.cra_module = THIS_MODULE,
187 		}
188 	}
189 };
190 
191 static int zynqmp_sha_probe(struct platform_device *pdev)
192 {
193 	struct device *dev = &pdev->dev;
194 	int err;
195 	u32 v;
196 
197 	/* Verify the hardware is present */
198 	err = zynqmp_pm_get_api_version(&v);
199 	if (err)
200 		return err;
201 
202 
203 	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(ZYNQMP_DMA_BIT_MASK));
204 	if (err < 0) {
205 		dev_err(dev, "No usable DMA configuration\n");
206 		return err;
207 	}
208 
209 	err = crypto_register_shash(&sha3_drv_ctx.sha3_384);
210 	if (err < 0) {
211 		dev_err(dev, "Failed to register shash alg.\n");
212 		return err;
213 	}
214 
215 	sha3_drv_ctx.dev = dev;
216 	platform_set_drvdata(pdev, &sha3_drv_ctx);
217 
218 	ubuf = dma_alloc_coherent(dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, &update_dma_addr, GFP_KERNEL);
219 	if (!ubuf) {
220 		err = -ENOMEM;
221 		goto err_shash;
222 	}
223 
224 	fbuf = dma_alloc_coherent(dev, SHA3_384_DIGEST_SIZE, &final_dma_addr, GFP_KERNEL);
225 	if (!fbuf) {
226 		err = -ENOMEM;
227 		goto err_mem;
228 	}
229 
230 	return 0;
231 
232 err_mem:
233 	dma_free_coherent(sha3_drv_ctx.dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, ubuf, update_dma_addr);
234 
235 err_shash:
236 	crypto_unregister_shash(&sha3_drv_ctx.sha3_384);
237 
238 	return err;
239 }
240 
241 static int zynqmp_sha_remove(struct platform_device *pdev)
242 {
243 	sha3_drv_ctx.dev = platform_get_drvdata(pdev);
244 
245 	dma_free_coherent(sha3_drv_ctx.dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, ubuf, update_dma_addr);
246 	dma_free_coherent(sha3_drv_ctx.dev, SHA3_384_DIGEST_SIZE, fbuf, final_dma_addr);
247 	crypto_unregister_shash(&sha3_drv_ctx.sha3_384);
248 
249 	return 0;
250 }
251 
252 static struct platform_driver zynqmp_sha_driver = {
253 	.probe = zynqmp_sha_probe,
254 	.remove = zynqmp_sha_remove,
255 	.driver = {
256 		.name = "zynqmp-sha3-384",
257 	},
258 };
259 
260 module_platform_driver(zynqmp_sha_driver);
261 MODULE_DESCRIPTION("ZynqMP SHA3 hardware acceleration support.");
262 MODULE_LICENSE("GPL v2");
263 MODULE_AUTHOR("Harsha <harsha.harsha@xilinx.com>");
264