xref: /linux/drivers/crypto/xilinx/zynqmp-sha.c (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce) !
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Xilinx ZynqMP SHA Driver.
4  * Copyright (c) 2022 Xilinx Inc.
5  */
6 #include <crypto/internal/hash.h>
7 #include <crypto/sha3.h>
8 #include <linux/cacheflush.h>
9 #include <linux/cleanup.h>
10 #include <linux/device.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/err.h>
13 #include <linux/firmware/xlnx-zynqmp.h>
14 #include <linux/io.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/spinlock.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 static dma_addr_t update_dma_addr, final_dma_addr;
40 static char *ubuf, *fbuf;
41 
42 static DEFINE_SPINLOCK(zynqmp_sha_lock);
43 
zynqmp_sha_init_tfm(struct crypto_shash * hash)44 static int zynqmp_sha_init_tfm(struct crypto_shash *hash)
45 {
46 	const char *fallback_driver_name = crypto_shash_alg_name(hash);
47 	struct zynqmp_sha_tfm_ctx *tfm_ctx = crypto_shash_ctx(hash);
48 	struct shash_alg *alg = crypto_shash_alg(hash);
49 	struct crypto_shash *fallback_tfm;
50 	struct zynqmp_sha_drv_ctx *drv_ctx;
51 
52 	drv_ctx = container_of(alg, struct zynqmp_sha_drv_ctx, sha3_384);
53 	tfm_ctx->dev = drv_ctx->dev;
54 
55 	/* Allocate a fallback and abort if it failed. */
56 	fallback_tfm = crypto_alloc_shash(fallback_driver_name, 0,
57 					  CRYPTO_ALG_NEED_FALLBACK);
58 	if (IS_ERR(fallback_tfm))
59 		return PTR_ERR(fallback_tfm);
60 
61 	if (crypto_shash_descsize(hash) <
62 	    crypto_shash_statesize(tfm_ctx->fbk_tfm)) {
63 		crypto_free_shash(fallback_tfm);
64 		return -EINVAL;
65 	}
66 
67 	tfm_ctx->fbk_tfm = fallback_tfm;
68 
69 	return 0;
70 }
71 
zynqmp_sha_exit_tfm(struct crypto_shash * hash)72 static void zynqmp_sha_exit_tfm(struct crypto_shash *hash)
73 {
74 	struct zynqmp_sha_tfm_ctx *tfm_ctx = crypto_shash_ctx(hash);
75 
76 	crypto_free_shash(tfm_ctx->fbk_tfm);
77 }
78 
zynqmp_sha_continue(struct shash_desc * desc,struct shash_desc * fbdesc,int err)79 static int zynqmp_sha_continue(struct shash_desc *desc,
80 			       struct shash_desc *fbdesc, int err)
81 {
82 	err = err ?: crypto_shash_export(fbdesc, shash_desc_ctx(desc));
83 	shash_desc_zero(fbdesc);
84 	return err;
85 }
86 
zynqmp_sha_init(struct shash_desc * desc)87 static int zynqmp_sha_init(struct shash_desc *desc)
88 {
89 	struct zynqmp_sha_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
90 	struct crypto_shash *fbtfm = tctx->fbk_tfm;
91 	SHASH_DESC_ON_STACK(fbdesc, fbtfm);
92 	int err;
93 
94 	fbdesc->tfm = fbtfm;
95 	err = crypto_shash_init(fbdesc);
96 	return zynqmp_sha_continue(desc, fbdesc, err);
97 }
98 
zynqmp_sha_update(struct shash_desc * desc,const u8 * data,unsigned int length)99 static int zynqmp_sha_update(struct shash_desc *desc, const u8 *data, unsigned int length)
100 {
101 	struct zynqmp_sha_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
102 	struct crypto_shash *fbtfm = tctx->fbk_tfm;
103 	SHASH_DESC_ON_STACK(fbdesc, fbtfm);
104 	int err;
105 
106 	fbdesc->tfm = fbtfm;
107 	err = crypto_shash_import(fbdesc, shash_desc_ctx(desc)) ?:
108 	      crypto_shash_update(fbdesc, data, length);
109 	return zynqmp_sha_continue(desc, fbdesc, err);
110 }
111 
zynqmp_sha_finup(struct shash_desc * desc,const u8 * data,unsigned int length,u8 * out)112 static int zynqmp_sha_finup(struct shash_desc *desc, const u8 *data, unsigned int length, u8 *out)
113 {
114 	struct zynqmp_sha_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
115 	struct crypto_shash *fbtfm = tctx->fbk_tfm;
116 	SHASH_DESC_ON_STACK(fbdesc, fbtfm);
117 
118 	fbdesc->tfm = fbtfm;
119 	return crypto_shash_import(fbdesc, shash_desc_ctx(desc)) ?:
120 	       crypto_shash_finup(fbdesc, data, length, out);
121 }
122 
__zynqmp_sha_digest(struct shash_desc * desc,const u8 * data,unsigned int len,u8 * out)123 static int __zynqmp_sha_digest(struct shash_desc *desc, const u8 *data,
124 			       unsigned int len, u8 *out)
125 {
126 	unsigned int remaining_len = len;
127 	int update_size;
128 	int ret;
129 
130 	ret = zynqmp_pm_sha_hash(0, 0, ZYNQMP_SHA3_INIT);
131 	if (ret)
132 		return ret;
133 
134 	while (remaining_len != 0) {
135 		memzero_explicit(ubuf, ZYNQMP_DMA_ALLOC_FIXED_SIZE);
136 		if (remaining_len >= ZYNQMP_DMA_ALLOC_FIXED_SIZE) {
137 			update_size = ZYNQMP_DMA_ALLOC_FIXED_SIZE;
138 			remaining_len -= ZYNQMP_DMA_ALLOC_FIXED_SIZE;
139 		} else {
140 			update_size = remaining_len;
141 			remaining_len = 0;
142 		}
143 		memcpy(ubuf, data, update_size);
144 		flush_icache_range((unsigned long)ubuf, (unsigned long)ubuf + update_size);
145 		ret = zynqmp_pm_sha_hash(update_dma_addr, update_size, ZYNQMP_SHA3_UPDATE);
146 		if (ret)
147 			return ret;
148 
149 		data += update_size;
150 	}
151 
152 	ret = zynqmp_pm_sha_hash(final_dma_addr, SHA3_384_DIGEST_SIZE, ZYNQMP_SHA3_FINAL);
153 	memcpy(out, fbuf, SHA3_384_DIGEST_SIZE);
154 	memzero_explicit(fbuf, SHA3_384_DIGEST_SIZE);
155 
156 	return ret;
157 }
158 
zynqmp_sha_digest(struct shash_desc * desc,const u8 * data,unsigned int len,u8 * out)159 static int zynqmp_sha_digest(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out)
160 {
161 	scoped_guard(spinlock_bh, &zynqmp_sha_lock)
162 		return __zynqmp_sha_digest(desc, data, len, out);
163 }
164 
165 static struct zynqmp_sha_drv_ctx sha3_drv_ctx = {
166 	.sha3_384 = {
167 		.init = zynqmp_sha_init,
168 		.update = zynqmp_sha_update,
169 		.finup = zynqmp_sha_finup,
170 		.digest = zynqmp_sha_digest,
171 		.init_tfm = zynqmp_sha_init_tfm,
172 		.exit_tfm = zynqmp_sha_exit_tfm,
173 		.descsize = SHA3_384_EXPORT_SIZE,
174 		.digestsize = SHA3_384_DIGEST_SIZE,
175 		.base = {
176 			.cra_name = "sha3-384",
177 			.cra_driver_name = "zynqmp-sha3-384",
178 			.cra_priority = 300,
179 			.cra_flags = CRYPTO_ALG_KERN_DRIVER_ONLY |
180 				     CRYPTO_ALG_NEED_FALLBACK,
181 			.cra_blocksize = SHA3_384_BLOCK_SIZE,
182 			.cra_ctxsize = sizeof(struct zynqmp_sha_tfm_ctx),
183 			.cra_module = THIS_MODULE,
184 		}
185 	}
186 };
187 
zynqmp_sha_probe(struct platform_device * pdev)188 static int zynqmp_sha_probe(struct platform_device *pdev)
189 {
190 	struct device *dev = &pdev->dev;
191 	int err;
192 	u32 v;
193 
194 	/* Verify the hardware is present */
195 	err = zynqmp_pm_get_api_version(&v);
196 	if (err)
197 		return err;
198 
199 
200 	err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(ZYNQMP_DMA_BIT_MASK));
201 	if (err < 0) {
202 		dev_err(dev, "No usable DMA configuration\n");
203 		return err;
204 	}
205 
206 	err = crypto_register_shash(&sha3_drv_ctx.sha3_384);
207 	if (err < 0) {
208 		dev_err(dev, "Failed to register shash alg.\n");
209 		return err;
210 	}
211 
212 	sha3_drv_ctx.dev = dev;
213 	platform_set_drvdata(pdev, &sha3_drv_ctx);
214 
215 	ubuf = dma_alloc_coherent(dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, &update_dma_addr, GFP_KERNEL);
216 	if (!ubuf) {
217 		err = -ENOMEM;
218 		goto err_shash;
219 	}
220 
221 	fbuf = dma_alloc_coherent(dev, SHA3_384_DIGEST_SIZE, &final_dma_addr, GFP_KERNEL);
222 	if (!fbuf) {
223 		err = -ENOMEM;
224 		goto err_mem;
225 	}
226 
227 	return 0;
228 
229 err_mem:
230 	dma_free_coherent(sha3_drv_ctx.dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, ubuf, update_dma_addr);
231 
232 err_shash:
233 	crypto_unregister_shash(&sha3_drv_ctx.sha3_384);
234 
235 	return err;
236 }
237 
zynqmp_sha_remove(struct platform_device * pdev)238 static void zynqmp_sha_remove(struct platform_device *pdev)
239 {
240 	sha3_drv_ctx.dev = platform_get_drvdata(pdev);
241 
242 	dma_free_coherent(sha3_drv_ctx.dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, ubuf, update_dma_addr);
243 	dma_free_coherent(sha3_drv_ctx.dev, SHA3_384_DIGEST_SIZE, fbuf, final_dma_addr);
244 	crypto_unregister_shash(&sha3_drv_ctx.sha3_384);
245 }
246 
247 static struct platform_driver zynqmp_sha_driver = {
248 	.probe = zynqmp_sha_probe,
249 	.remove = zynqmp_sha_remove,
250 	.driver = {
251 		.name = "zynqmp-sha3-384",
252 	},
253 };
254 
255 module_platform_driver(zynqmp_sha_driver);
256 MODULE_DESCRIPTION("ZynqMP SHA3 hardware acceleration support.");
257 MODULE_LICENSE("GPL v2");
258 MODULE_AUTHOR("Harsha <harsha.harsha@xilinx.com>");
259