xref: /openbmc/linux/arch/x86/crypto/des3_ede_glue.c (revision 842ed298)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Glue Code for assembler optimized version of 3DES
4  *
5  * Copyright © 2014 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
6  *
7  * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
8  *   Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
9  * CTR part based on code (crypto/ctr.c) by:
10  *   (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
11  */
12 
13 #include <crypto/algapi.h>
14 #include <crypto/des.h>
15 #include <crypto/internal/skcipher.h>
16 #include <linux/crypto.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/types.h>
20 
21 struct des3_ede_x86_ctx {
22 	struct des3_ede_ctx enc;
23 	struct des3_ede_ctx dec;
24 };
25 
26 /* regular block cipher functions */
27 asmlinkage void des3_ede_x86_64_crypt_blk(const u32 *expkey, u8 *dst,
28 					  const u8 *src);
29 
30 /* 3-way parallel cipher functions */
31 asmlinkage void des3_ede_x86_64_crypt_blk_3way(const u32 *expkey, u8 *dst,
32 					       const u8 *src);
33 
34 static inline void des3_ede_enc_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
35 				    const u8 *src)
36 {
37 	u32 *enc_ctx = ctx->enc.expkey;
38 
39 	des3_ede_x86_64_crypt_blk(enc_ctx, dst, src);
40 }
41 
42 static inline void des3_ede_dec_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
43 				    const u8 *src)
44 {
45 	u32 *dec_ctx = ctx->dec.expkey;
46 
47 	des3_ede_x86_64_crypt_blk(dec_ctx, dst, src);
48 }
49 
50 static inline void des3_ede_enc_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
51 					 const u8 *src)
52 {
53 	u32 *enc_ctx = ctx->enc.expkey;
54 
55 	des3_ede_x86_64_crypt_blk_3way(enc_ctx, dst, src);
56 }
57 
58 static inline void des3_ede_dec_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
59 					 const u8 *src)
60 {
61 	u32 *dec_ctx = ctx->dec.expkey;
62 
63 	des3_ede_x86_64_crypt_blk_3way(dec_ctx, dst, src);
64 }
65 
66 static void des3_ede_x86_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
67 {
68 	des3_ede_enc_blk(crypto_tfm_ctx(tfm), dst, src);
69 }
70 
71 static void des3_ede_x86_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
72 {
73 	des3_ede_dec_blk(crypto_tfm_ctx(tfm), dst, src);
74 }
75 
76 static int ecb_crypt(struct skcipher_request *req, const u32 *expkey)
77 {
78 	const unsigned int bsize = DES3_EDE_BLOCK_SIZE;
79 	struct skcipher_walk walk;
80 	unsigned int nbytes;
81 	int err;
82 
83 	err = skcipher_walk_virt(&walk, req, false);
84 
85 	while ((nbytes = walk.nbytes)) {
86 		u8 *wsrc = walk.src.virt.addr;
87 		u8 *wdst = walk.dst.virt.addr;
88 
89 		/* Process four block batch */
90 		if (nbytes >= bsize * 3) {
91 			do {
92 				des3_ede_x86_64_crypt_blk_3way(expkey, wdst,
93 							       wsrc);
94 
95 				wsrc += bsize * 3;
96 				wdst += bsize * 3;
97 				nbytes -= bsize * 3;
98 			} while (nbytes >= bsize * 3);
99 
100 			if (nbytes < bsize)
101 				goto done;
102 		}
103 
104 		/* Handle leftovers */
105 		do {
106 			des3_ede_x86_64_crypt_blk(expkey, wdst, wsrc);
107 
108 			wsrc += bsize;
109 			wdst += bsize;
110 			nbytes -= bsize;
111 		} while (nbytes >= bsize);
112 
113 done:
114 		err = skcipher_walk_done(&walk, nbytes);
115 	}
116 
117 	return err;
118 }
119 
120 static int ecb_encrypt(struct skcipher_request *req)
121 {
122 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
123 	struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
124 
125 	return ecb_crypt(req, ctx->enc.expkey);
126 }
127 
128 static int ecb_decrypt(struct skcipher_request *req)
129 {
130 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
131 	struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
132 
133 	return ecb_crypt(req, ctx->dec.expkey);
134 }
135 
136 static unsigned int __cbc_encrypt(struct des3_ede_x86_ctx *ctx,
137 				  struct skcipher_walk *walk)
138 {
139 	unsigned int bsize = DES3_EDE_BLOCK_SIZE;
140 	unsigned int nbytes = walk->nbytes;
141 	u64 *src = (u64 *)walk->src.virt.addr;
142 	u64 *dst = (u64 *)walk->dst.virt.addr;
143 	u64 *iv = (u64 *)walk->iv;
144 
145 	do {
146 		*dst = *src ^ *iv;
147 		des3_ede_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
148 		iv = dst;
149 
150 		src += 1;
151 		dst += 1;
152 		nbytes -= bsize;
153 	} while (nbytes >= bsize);
154 
155 	*(u64 *)walk->iv = *iv;
156 	return nbytes;
157 }
158 
159 static int cbc_encrypt(struct skcipher_request *req)
160 {
161 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
162 	struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
163 	struct skcipher_walk walk;
164 	unsigned int nbytes;
165 	int err;
166 
167 	err = skcipher_walk_virt(&walk, req, false);
168 
169 	while ((nbytes = walk.nbytes)) {
170 		nbytes = __cbc_encrypt(ctx, &walk);
171 		err = skcipher_walk_done(&walk, nbytes);
172 	}
173 
174 	return err;
175 }
176 
177 static unsigned int __cbc_decrypt(struct des3_ede_x86_ctx *ctx,
178 				  struct skcipher_walk *walk)
179 {
180 	unsigned int bsize = DES3_EDE_BLOCK_SIZE;
181 	unsigned int nbytes = walk->nbytes;
182 	u64 *src = (u64 *)walk->src.virt.addr;
183 	u64 *dst = (u64 *)walk->dst.virt.addr;
184 	u64 ivs[3 - 1];
185 	u64 last_iv;
186 
187 	/* Start of the last block. */
188 	src += nbytes / bsize - 1;
189 	dst += nbytes / bsize - 1;
190 
191 	last_iv = *src;
192 
193 	/* Process four block batch */
194 	if (nbytes >= bsize * 3) {
195 		do {
196 			nbytes -= bsize * 3 - bsize;
197 			src -= 3 - 1;
198 			dst -= 3 - 1;
199 
200 			ivs[0] = src[0];
201 			ivs[1] = src[1];
202 
203 			des3_ede_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
204 
205 			dst[1] ^= ivs[0];
206 			dst[2] ^= ivs[1];
207 
208 			nbytes -= bsize;
209 			if (nbytes < bsize)
210 				goto done;
211 
212 			*dst ^= *(src - 1);
213 			src -= 1;
214 			dst -= 1;
215 		} while (nbytes >= bsize * 3);
216 	}
217 
218 	/* Handle leftovers */
219 	for (;;) {
220 		des3_ede_dec_blk(ctx, (u8 *)dst, (u8 *)src);
221 
222 		nbytes -= bsize;
223 		if (nbytes < bsize)
224 			break;
225 
226 		*dst ^= *(src - 1);
227 		src -= 1;
228 		dst -= 1;
229 	}
230 
231 done:
232 	*dst ^= *(u64 *)walk->iv;
233 	*(u64 *)walk->iv = last_iv;
234 
235 	return nbytes;
236 }
237 
238 static int cbc_decrypt(struct skcipher_request *req)
239 {
240 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
241 	struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
242 	struct skcipher_walk walk;
243 	unsigned int nbytes;
244 	int err;
245 
246 	err = skcipher_walk_virt(&walk, req, false);
247 
248 	while ((nbytes = walk.nbytes)) {
249 		nbytes = __cbc_decrypt(ctx, &walk);
250 		err = skcipher_walk_done(&walk, nbytes);
251 	}
252 
253 	return err;
254 }
255 
256 static void ctr_crypt_final(struct des3_ede_x86_ctx *ctx,
257 			    struct skcipher_walk *walk)
258 {
259 	u8 *ctrblk = walk->iv;
260 	u8 keystream[DES3_EDE_BLOCK_SIZE];
261 	u8 *src = walk->src.virt.addr;
262 	u8 *dst = walk->dst.virt.addr;
263 	unsigned int nbytes = walk->nbytes;
264 
265 	des3_ede_enc_blk(ctx, keystream, ctrblk);
266 	crypto_xor_cpy(dst, keystream, src, nbytes);
267 
268 	crypto_inc(ctrblk, DES3_EDE_BLOCK_SIZE);
269 }
270 
271 static unsigned int __ctr_crypt(struct des3_ede_x86_ctx *ctx,
272 				struct skcipher_walk *walk)
273 {
274 	unsigned int bsize = DES3_EDE_BLOCK_SIZE;
275 	unsigned int nbytes = walk->nbytes;
276 	__be64 *src = (__be64 *)walk->src.virt.addr;
277 	__be64 *dst = (__be64 *)walk->dst.virt.addr;
278 	u64 ctrblk = be64_to_cpu(*(__be64 *)walk->iv);
279 	__be64 ctrblocks[3];
280 
281 	/* Process four block batch */
282 	if (nbytes >= bsize * 3) {
283 		do {
284 			/* create ctrblks for parallel encrypt */
285 			ctrblocks[0] = cpu_to_be64(ctrblk++);
286 			ctrblocks[1] = cpu_to_be64(ctrblk++);
287 			ctrblocks[2] = cpu_to_be64(ctrblk++);
288 
289 			des3_ede_enc_blk_3way(ctx, (u8 *)ctrblocks,
290 					      (u8 *)ctrblocks);
291 
292 			dst[0] = src[0] ^ ctrblocks[0];
293 			dst[1] = src[1] ^ ctrblocks[1];
294 			dst[2] = src[2] ^ ctrblocks[2];
295 
296 			src += 3;
297 			dst += 3;
298 		} while ((nbytes -= bsize * 3) >= bsize * 3);
299 
300 		if (nbytes < bsize)
301 			goto done;
302 	}
303 
304 	/* Handle leftovers */
305 	do {
306 		ctrblocks[0] = cpu_to_be64(ctrblk++);
307 
308 		des3_ede_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
309 
310 		dst[0] = src[0] ^ ctrblocks[0];
311 
312 		src += 1;
313 		dst += 1;
314 	} while ((nbytes -= bsize) >= bsize);
315 
316 done:
317 	*(__be64 *)walk->iv = cpu_to_be64(ctrblk);
318 	return nbytes;
319 }
320 
321 static int ctr_crypt(struct skcipher_request *req)
322 {
323 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
324 	struct des3_ede_x86_ctx *ctx = crypto_skcipher_ctx(tfm);
325 	struct skcipher_walk walk;
326 	unsigned int nbytes;
327 	int err;
328 
329 	err = skcipher_walk_virt(&walk, req, false);
330 
331 	while ((nbytes = walk.nbytes) >= DES3_EDE_BLOCK_SIZE) {
332 		nbytes = __ctr_crypt(ctx, &walk);
333 		err = skcipher_walk_done(&walk, nbytes);
334 	}
335 
336 	if (nbytes) {
337 		ctr_crypt_final(ctx, &walk);
338 		err = skcipher_walk_done(&walk, 0);
339 	}
340 
341 	return err;
342 }
343 
344 static int des3_ede_x86_setkey(struct crypto_tfm *tfm, const u8 *key,
345 			       unsigned int keylen)
346 {
347 	struct des3_ede_x86_ctx *ctx = crypto_tfm_ctx(tfm);
348 	u32 i, j, tmp;
349 	int err;
350 
351 	err = des3_ede_expand_key(&ctx->enc, key, keylen);
352 	if (err == -ENOKEY) {
353 		if (crypto_tfm_get_flags(tfm) & CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)
354 			err = -EINVAL;
355 		else
356 			err = 0;
357 	}
358 
359 	if (err) {
360 		memset(ctx, 0, sizeof(*ctx));
361 		return err;
362 	}
363 
364 	/* Fix encryption context for this implementation and form decryption
365 	 * context. */
366 	j = DES3_EDE_EXPKEY_WORDS - 2;
367 	for (i = 0; i < DES3_EDE_EXPKEY_WORDS; i += 2, j -= 2) {
368 		tmp = ror32(ctx->enc.expkey[i + 1], 4);
369 		ctx->enc.expkey[i + 1] = tmp;
370 
371 		ctx->dec.expkey[j + 0] = ctx->enc.expkey[i + 0];
372 		ctx->dec.expkey[j + 1] = tmp;
373 	}
374 
375 	return 0;
376 }
377 
378 static int des3_ede_x86_setkey_skcipher(struct crypto_skcipher *tfm,
379 					const u8 *key,
380 					unsigned int keylen)
381 {
382 	return des3_ede_x86_setkey(&tfm->base, key, keylen);
383 }
384 
385 static struct crypto_alg des3_ede_cipher = {
386 	.cra_name		= "des3_ede",
387 	.cra_driver_name	= "des3_ede-asm",
388 	.cra_priority		= 200,
389 	.cra_flags		= CRYPTO_ALG_TYPE_CIPHER,
390 	.cra_blocksize		= DES3_EDE_BLOCK_SIZE,
391 	.cra_ctxsize		= sizeof(struct des3_ede_x86_ctx),
392 	.cra_alignmask		= 0,
393 	.cra_module		= THIS_MODULE,
394 	.cra_u = {
395 		.cipher = {
396 			.cia_min_keysize	= DES3_EDE_KEY_SIZE,
397 			.cia_max_keysize	= DES3_EDE_KEY_SIZE,
398 			.cia_setkey		= des3_ede_x86_setkey,
399 			.cia_encrypt		= des3_ede_x86_encrypt,
400 			.cia_decrypt		= des3_ede_x86_decrypt,
401 		}
402 	}
403 };
404 
405 static struct skcipher_alg des3_ede_skciphers[] = {
406 	{
407 		.base.cra_name		= "ecb(des3_ede)",
408 		.base.cra_driver_name	= "ecb-des3_ede-asm",
409 		.base.cra_priority	= 300,
410 		.base.cra_blocksize	= DES3_EDE_BLOCK_SIZE,
411 		.base.cra_ctxsize	= sizeof(struct des3_ede_x86_ctx),
412 		.base.cra_module	= THIS_MODULE,
413 		.min_keysize		= DES3_EDE_KEY_SIZE,
414 		.max_keysize		= DES3_EDE_KEY_SIZE,
415 		.setkey			= des3_ede_x86_setkey_skcipher,
416 		.encrypt		= ecb_encrypt,
417 		.decrypt		= ecb_decrypt,
418 	}, {
419 		.base.cra_name		= "cbc(des3_ede)",
420 		.base.cra_driver_name	= "cbc-des3_ede-asm",
421 		.base.cra_priority	= 300,
422 		.base.cra_blocksize	= DES3_EDE_BLOCK_SIZE,
423 		.base.cra_ctxsize	= sizeof(struct des3_ede_x86_ctx),
424 		.base.cra_module	= THIS_MODULE,
425 		.min_keysize		= DES3_EDE_KEY_SIZE,
426 		.max_keysize		= DES3_EDE_KEY_SIZE,
427 		.ivsize			= DES3_EDE_BLOCK_SIZE,
428 		.setkey			= des3_ede_x86_setkey_skcipher,
429 		.encrypt		= cbc_encrypt,
430 		.decrypt		= cbc_decrypt,
431 	}, {
432 		.base.cra_name		= "ctr(des3_ede)",
433 		.base.cra_driver_name	= "ctr-des3_ede-asm",
434 		.base.cra_priority	= 300,
435 		.base.cra_blocksize	= 1,
436 		.base.cra_ctxsize	= sizeof(struct des3_ede_x86_ctx),
437 		.base.cra_module	= THIS_MODULE,
438 		.min_keysize		= DES3_EDE_KEY_SIZE,
439 		.max_keysize		= DES3_EDE_KEY_SIZE,
440 		.ivsize			= DES3_EDE_BLOCK_SIZE,
441 		.chunksize		= DES3_EDE_BLOCK_SIZE,
442 		.setkey			= des3_ede_x86_setkey_skcipher,
443 		.encrypt		= ctr_crypt,
444 		.decrypt		= ctr_crypt,
445 	}
446 };
447 
448 static bool is_blacklisted_cpu(void)
449 {
450 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
451 		return false;
452 
453 	if (boot_cpu_data.x86 == 0x0f) {
454 		/*
455 		 * On Pentium 4, des3_ede-x86_64 is slower than generic C
456 		 * implementation because use of 64bit rotates (which are really
457 		 * slow on P4). Therefore blacklist P4s.
458 		 */
459 		return true;
460 	}
461 
462 	return false;
463 }
464 
465 static int force;
466 module_param(force, int, 0);
467 MODULE_PARM_DESC(force, "Force module load, ignore CPU blacklist");
468 
469 static int __init des3_ede_x86_init(void)
470 {
471 	int err;
472 
473 	if (!force && is_blacklisted_cpu()) {
474 		pr_info("des3_ede-x86_64: performance on this CPU would be suboptimal: disabling des3_ede-x86_64.\n");
475 		return -ENODEV;
476 	}
477 
478 	err = crypto_register_alg(&des3_ede_cipher);
479 	if (err)
480 		return err;
481 
482 	err = crypto_register_skciphers(des3_ede_skciphers,
483 					ARRAY_SIZE(des3_ede_skciphers));
484 	if (err)
485 		crypto_unregister_alg(&des3_ede_cipher);
486 
487 	return err;
488 }
489 
490 static void __exit des3_ede_x86_fini(void)
491 {
492 	crypto_unregister_alg(&des3_ede_cipher);
493 	crypto_unregister_skciphers(des3_ede_skciphers,
494 				    ARRAY_SIZE(des3_ede_skciphers));
495 }
496 
497 module_init(des3_ede_x86_init);
498 module_exit(des3_ede_x86_fini);
499 
500 MODULE_LICENSE("GPL");
501 MODULE_DESCRIPTION("Triple DES EDE Cipher Algorithm, asm optimized");
502 MODULE_ALIAS_CRYPTO("des3_ede");
503 MODULE_ALIAS_CRYPTO("des3_ede-asm");
504 MODULE_AUTHOR("Jussi Kivilinna <jussi.kivilinna@iki.fi>");
505