xref: /openbmc/linux/arch/s390/crypto/crc32-vx.c (revision ba61bb17)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Crypto-API module for CRC-32 algorithms implemented with the
4  * z/Architecture Vector Extension Facility.
5  *
6  * Copyright IBM Corp. 2015
7  * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
8  */
9 #define KMSG_COMPONENT	"crc32-vx"
10 #define pr_fmt(fmt)	KMSG_COMPONENT ": " fmt
11 
12 #include <linux/module.h>
13 #include <linux/cpufeature.h>
14 #include <linux/crc32.h>
15 #include <crypto/internal/hash.h>
16 #include <asm/fpu/api.h>
17 
18 
19 #define CRC32_BLOCK_SIZE	1
20 #define CRC32_DIGEST_SIZE	4
21 
22 #define VX_MIN_LEN		64
23 #define VX_ALIGNMENT		16L
24 #define VX_ALIGN_MASK		(VX_ALIGNMENT - 1)
25 
26 struct crc_ctx {
27 	u32 key;
28 };
29 
30 struct crc_desc_ctx {
31 	u32 crc;
32 };
33 
34 /* Prototypes for functions in assembly files */
35 u32 crc32_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
36 u32 crc32_be_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
37 u32 crc32c_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size);
38 
39 /*
40  * DEFINE_CRC32_VX() - Define a CRC-32 function using the vector extension
41  *
42  * Creates a function to perform a particular CRC-32 computation. Depending
43  * on the message buffer, the hardware-accelerated or software implementation
44  * is used.   Note that the message buffer is aligned to improve fetch
45  * operations of VECTOR LOAD MULTIPLE instructions.
46  *
47  */
48 #define DEFINE_CRC32_VX(___fname, ___crc32_vx, ___crc32_sw)		    \
49 	static u32 __pure ___fname(u32 crc,				    \
50 				unsigned char const *data, size_t datalen)  \
51 	{								    \
52 		struct kernel_fpu vxstate;				    \
53 		unsigned long prealign, aligned, remaining;		    \
54 									    \
55 		if (datalen < VX_MIN_LEN + VX_ALIGN_MASK)		    \
56 			return ___crc32_sw(crc, data, datalen);		    \
57 									    \
58 		if ((unsigned long)data & VX_ALIGN_MASK) {		    \
59 			prealign = VX_ALIGNMENT -			    \
60 				  ((unsigned long)data & VX_ALIGN_MASK);    \
61 			datalen -= prealign;				    \
62 			crc = ___crc32_sw(crc, data, prealign);		    \
63 			data = (void *)((unsigned long)data + prealign);    \
64 		}							    \
65 									    \
66 		aligned = datalen & ~VX_ALIGN_MASK;			    \
67 		remaining = datalen & VX_ALIGN_MASK;			    \
68 									    \
69 		kernel_fpu_begin(&vxstate, KERNEL_VXR_LOW);		    \
70 		crc = ___crc32_vx(crc, data, aligned);			    \
71 		kernel_fpu_end(&vxstate, KERNEL_VXR_LOW);		    \
72 									    \
73 		if (remaining)						    \
74 			crc = ___crc32_sw(crc, data + aligned, remaining);  \
75 									    \
76 		return crc;						    \
77 	}
78 
79 DEFINE_CRC32_VX(crc32_le_vx, crc32_le_vgfm_16, crc32_le)
80 DEFINE_CRC32_VX(crc32_be_vx, crc32_be_vgfm_16, crc32_be)
81 DEFINE_CRC32_VX(crc32c_le_vx, crc32c_le_vgfm_16, __crc32c_le)
82 
83 
84 static int crc32_vx_cra_init_zero(struct crypto_tfm *tfm)
85 {
86 	struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
87 
88 	mctx->key = 0;
89 	return 0;
90 }
91 
92 static int crc32_vx_cra_init_invert(struct crypto_tfm *tfm)
93 {
94 	struct crc_ctx *mctx = crypto_tfm_ctx(tfm);
95 
96 	mctx->key = ~0;
97 	return 0;
98 }
99 
100 static int crc32_vx_init(struct shash_desc *desc)
101 {
102 	struct crc_ctx *mctx = crypto_shash_ctx(desc->tfm);
103 	struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
104 
105 	ctx->crc = mctx->key;
106 	return 0;
107 }
108 
109 static int crc32_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
110 			   unsigned int newkeylen)
111 {
112 	struct crc_ctx *mctx = crypto_shash_ctx(tfm);
113 
114 	if (newkeylen != sizeof(mctx->key)) {
115 		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
116 		return -EINVAL;
117 	}
118 	mctx->key = le32_to_cpu(*(__le32 *)newkey);
119 	return 0;
120 }
121 
122 static int crc32be_vx_setkey(struct crypto_shash *tfm, const u8 *newkey,
123 			     unsigned int newkeylen)
124 {
125 	struct crc_ctx *mctx = crypto_shash_ctx(tfm);
126 
127 	if (newkeylen != sizeof(mctx->key)) {
128 		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
129 		return -EINVAL;
130 	}
131 	mctx->key = be32_to_cpu(*(__be32 *)newkey);
132 	return 0;
133 }
134 
135 static int crc32le_vx_final(struct shash_desc *desc, u8 *out)
136 {
137 	struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
138 
139 	*(__le32 *)out = cpu_to_le32p(&ctx->crc);
140 	return 0;
141 }
142 
143 static int crc32be_vx_final(struct shash_desc *desc, u8 *out)
144 {
145 	struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
146 
147 	*(__be32 *)out = cpu_to_be32p(&ctx->crc);
148 	return 0;
149 }
150 
151 static int crc32c_vx_final(struct shash_desc *desc, u8 *out)
152 {
153 	struct crc_desc_ctx *ctx = shash_desc_ctx(desc);
154 
155 	/*
156 	 * Perform a final XOR with 0xFFFFFFFF to be in sync
157 	 * with the generic crc32c shash implementation.
158 	 */
159 	*(__le32 *)out = ~cpu_to_le32p(&ctx->crc);
160 	return 0;
161 }
162 
163 static int __crc32le_vx_finup(u32 *crc, const u8 *data, unsigned int len,
164 			      u8 *out)
165 {
166 	*(__le32 *)out = cpu_to_le32(crc32_le_vx(*crc, data, len));
167 	return 0;
168 }
169 
170 static int __crc32be_vx_finup(u32 *crc, const u8 *data, unsigned int len,
171 			      u8 *out)
172 {
173 	*(__be32 *)out = cpu_to_be32(crc32_be_vx(*crc, data, len));
174 	return 0;
175 }
176 
177 static int __crc32c_vx_finup(u32 *crc, const u8 *data, unsigned int len,
178 			     u8 *out)
179 {
180 	/*
181 	 * Perform a final XOR with 0xFFFFFFFF to be in sync
182 	 * with the generic crc32c shash implementation.
183 	 */
184 	*(__le32 *)out = ~cpu_to_le32(crc32c_le_vx(*crc, data, len));
185 	return 0;
186 }
187 
188 
189 #define CRC32_VX_FINUP(alg, func)					      \
190 	static int alg ## _vx_finup(struct shash_desc *desc, const u8 *data,  \
191 				   unsigned int datalen, u8 *out)	      \
192 	{								      \
193 		return __ ## alg ## _vx_finup(shash_desc_ctx(desc),	      \
194 					      data, datalen, out);	      \
195 	}
196 
197 CRC32_VX_FINUP(crc32le, crc32_le_vx)
198 CRC32_VX_FINUP(crc32be, crc32_be_vx)
199 CRC32_VX_FINUP(crc32c, crc32c_le_vx)
200 
201 #define CRC32_VX_DIGEST(alg, func)					      \
202 	static int alg ## _vx_digest(struct shash_desc *desc, const u8 *data, \
203 				     unsigned int len, u8 *out)		      \
204 	{								      \
205 		return __ ## alg ## _vx_finup(crypto_shash_ctx(desc->tfm),    \
206 					      data, len, out);		      \
207 	}
208 
209 CRC32_VX_DIGEST(crc32le, crc32_le_vx)
210 CRC32_VX_DIGEST(crc32be, crc32_be_vx)
211 CRC32_VX_DIGEST(crc32c, crc32c_le_vx)
212 
213 #define CRC32_VX_UPDATE(alg, func)					      \
214 	static int alg ## _vx_update(struct shash_desc *desc, const u8 *data, \
215 				     unsigned int datalen)		      \
216 	{								      \
217 		struct crc_desc_ctx *ctx = shash_desc_ctx(desc);	      \
218 		ctx->crc = func(ctx->crc, data, datalen);		      \
219 		return 0;						      \
220 	}
221 
222 CRC32_VX_UPDATE(crc32le, crc32_le_vx)
223 CRC32_VX_UPDATE(crc32be, crc32_be_vx)
224 CRC32_VX_UPDATE(crc32c, crc32c_le_vx)
225 
226 
227 static struct shash_alg crc32_vx_algs[] = {
228 	/* CRC-32 LE */
229 	{
230 		.init		=	crc32_vx_init,
231 		.setkey		=	crc32_vx_setkey,
232 		.update		=	crc32le_vx_update,
233 		.final		=	crc32le_vx_final,
234 		.finup		=	crc32le_vx_finup,
235 		.digest		=	crc32le_vx_digest,
236 		.descsize	=	sizeof(struct crc_desc_ctx),
237 		.digestsize	=	CRC32_DIGEST_SIZE,
238 		.base		=	{
239 			.cra_name	 = "crc32",
240 			.cra_driver_name = "crc32-vx",
241 			.cra_priority	 = 200,
242 			.cra_flags	 = CRYPTO_ALG_OPTIONAL_KEY,
243 			.cra_blocksize	 = CRC32_BLOCK_SIZE,
244 			.cra_ctxsize	 = sizeof(struct crc_ctx),
245 			.cra_module	 = THIS_MODULE,
246 			.cra_init	 = crc32_vx_cra_init_zero,
247 		},
248 	},
249 	/* CRC-32 BE */
250 	{
251 		.init		=	crc32_vx_init,
252 		.setkey		=	crc32be_vx_setkey,
253 		.update		=	crc32be_vx_update,
254 		.final		=	crc32be_vx_final,
255 		.finup		=	crc32be_vx_finup,
256 		.digest		=	crc32be_vx_digest,
257 		.descsize	=	sizeof(struct crc_desc_ctx),
258 		.digestsize	=	CRC32_DIGEST_SIZE,
259 		.base		=	{
260 			.cra_name	 = "crc32be",
261 			.cra_driver_name = "crc32be-vx",
262 			.cra_priority	 = 200,
263 			.cra_flags	 = CRYPTO_ALG_OPTIONAL_KEY,
264 			.cra_blocksize	 = CRC32_BLOCK_SIZE,
265 			.cra_ctxsize	 = sizeof(struct crc_ctx),
266 			.cra_module	 = THIS_MODULE,
267 			.cra_init	 = crc32_vx_cra_init_zero,
268 		},
269 	},
270 	/* CRC-32C LE */
271 	{
272 		.init		=	crc32_vx_init,
273 		.setkey		=	crc32_vx_setkey,
274 		.update		=	crc32c_vx_update,
275 		.final		=	crc32c_vx_final,
276 		.finup		=	crc32c_vx_finup,
277 		.digest		=	crc32c_vx_digest,
278 		.descsize	=	sizeof(struct crc_desc_ctx),
279 		.digestsize	=	CRC32_DIGEST_SIZE,
280 		.base		=	{
281 			.cra_name	 = "crc32c",
282 			.cra_driver_name = "crc32c-vx",
283 			.cra_priority	 = 200,
284 			.cra_flags	 = CRYPTO_ALG_OPTIONAL_KEY,
285 			.cra_blocksize	 = CRC32_BLOCK_SIZE,
286 			.cra_ctxsize	 = sizeof(struct crc_ctx),
287 			.cra_module	 = THIS_MODULE,
288 			.cra_init	 = crc32_vx_cra_init_invert,
289 		},
290 	},
291 };
292 
293 
294 static int __init crc_vx_mod_init(void)
295 {
296 	return crypto_register_shashes(crc32_vx_algs,
297 				       ARRAY_SIZE(crc32_vx_algs));
298 }
299 
300 static void __exit crc_vx_mod_exit(void)
301 {
302 	crypto_unregister_shashes(crc32_vx_algs, ARRAY_SIZE(crc32_vx_algs));
303 }
304 
305 module_cpu_feature_match(VXRS, crc_vx_mod_init);
306 module_exit(crc_vx_mod_exit);
307 
308 MODULE_AUTHOR("Hendrik Brueckner <brueckner@linux.vnet.ibm.com>");
309 MODULE_LICENSE("GPL");
310 
311 MODULE_ALIAS_CRYPTO("crc32");
312 MODULE_ALIAS_CRYPTO("crc32-vx");
313 MODULE_ALIAS_CRYPTO("crc32c");
314 MODULE_ALIAS_CRYPTO("crc32c-vx");
315