xref: /openbmc/linux/arch/x86/crypto/des3_ede_glue.c (revision 293d5b43)
1 /*
2  * Glue Code for assembler optimized version of 3DES
3  *
4  * Copyright © 2014 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
5  *
6  * CBC & ECB parts based on code (crypto/cbc.c,ecb.c) by:
7  *   Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
8  * CTR part based on code (crypto/ctr.c) by:
9  *   (C) Copyright IBM Corp. 2007 - Joy Latten <latten@us.ibm.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  */
22 
23 #include <asm/processor.h>
24 #include <crypto/des.h>
25 #include <linux/crypto.h>
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <linux/types.h>
29 #include <crypto/algapi.h>
30 
31 struct des3_ede_x86_ctx {
32 	u32 enc_expkey[DES3_EDE_EXPKEY_WORDS];
33 	u32 dec_expkey[DES3_EDE_EXPKEY_WORDS];
34 };
35 
36 /* regular block cipher functions */
37 asmlinkage void des3_ede_x86_64_crypt_blk(const u32 *expkey, u8 *dst,
38 					  const u8 *src);
39 
40 /* 3-way parallel cipher functions */
41 asmlinkage void des3_ede_x86_64_crypt_blk_3way(const u32 *expkey, u8 *dst,
42 					       const u8 *src);
43 
44 static inline void des3_ede_enc_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
45 				    const u8 *src)
46 {
47 	u32 *enc_ctx = ctx->enc_expkey;
48 
49 	des3_ede_x86_64_crypt_blk(enc_ctx, dst, src);
50 }
51 
52 static inline void des3_ede_dec_blk(struct des3_ede_x86_ctx *ctx, u8 *dst,
53 				    const u8 *src)
54 {
55 	u32 *dec_ctx = ctx->dec_expkey;
56 
57 	des3_ede_x86_64_crypt_blk(dec_ctx, dst, src);
58 }
59 
60 static inline void des3_ede_enc_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
61 					 const u8 *src)
62 {
63 	u32 *enc_ctx = ctx->enc_expkey;
64 
65 	des3_ede_x86_64_crypt_blk_3way(enc_ctx, dst, src);
66 }
67 
68 static inline void des3_ede_dec_blk_3way(struct des3_ede_x86_ctx *ctx, u8 *dst,
69 					 const u8 *src)
70 {
71 	u32 *dec_ctx = ctx->dec_expkey;
72 
73 	des3_ede_x86_64_crypt_blk_3way(dec_ctx, dst, src);
74 }
75 
76 static void des3_ede_x86_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
77 {
78 	des3_ede_enc_blk(crypto_tfm_ctx(tfm), dst, src);
79 }
80 
81 static void des3_ede_x86_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
82 {
83 	des3_ede_dec_blk(crypto_tfm_ctx(tfm), dst, src);
84 }
85 
86 static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk,
87 		     const u32 *expkey)
88 {
89 	unsigned int bsize = DES3_EDE_BLOCK_SIZE;
90 	unsigned int nbytes;
91 	int err;
92 
93 	err = blkcipher_walk_virt(desc, walk);
94 
95 	while ((nbytes = walk->nbytes)) {
96 		u8 *wsrc = walk->src.virt.addr;
97 		u8 *wdst = walk->dst.virt.addr;
98 
99 		/* Process four block batch */
100 		if (nbytes >= bsize * 3) {
101 			do {
102 				des3_ede_x86_64_crypt_blk_3way(expkey, wdst,
103 							       wsrc);
104 
105 				wsrc += bsize * 3;
106 				wdst += bsize * 3;
107 				nbytes -= bsize * 3;
108 			} while (nbytes >= bsize * 3);
109 
110 			if (nbytes < bsize)
111 				goto done;
112 		}
113 
114 		/* Handle leftovers */
115 		do {
116 			des3_ede_x86_64_crypt_blk(expkey, wdst, wsrc);
117 
118 			wsrc += bsize;
119 			wdst += bsize;
120 			nbytes -= bsize;
121 		} while (nbytes >= bsize);
122 
123 done:
124 		err = blkcipher_walk_done(desc, walk, nbytes);
125 	}
126 
127 	return err;
128 }
129 
130 static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
131 		       struct scatterlist *src, unsigned int nbytes)
132 {
133 	struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
134 	struct blkcipher_walk walk;
135 
136 	blkcipher_walk_init(&walk, dst, src, nbytes);
137 	return ecb_crypt(desc, &walk, ctx->enc_expkey);
138 }
139 
140 static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
141 		       struct scatterlist *src, unsigned int nbytes)
142 {
143 	struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
144 	struct blkcipher_walk walk;
145 
146 	blkcipher_walk_init(&walk, dst, src, nbytes);
147 	return ecb_crypt(desc, &walk, ctx->dec_expkey);
148 }
149 
150 static unsigned int __cbc_encrypt(struct blkcipher_desc *desc,
151 				  struct blkcipher_walk *walk)
152 {
153 	struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
154 	unsigned int bsize = DES3_EDE_BLOCK_SIZE;
155 	unsigned int nbytes = walk->nbytes;
156 	u64 *src = (u64 *)walk->src.virt.addr;
157 	u64 *dst = (u64 *)walk->dst.virt.addr;
158 	u64 *iv = (u64 *)walk->iv;
159 
160 	do {
161 		*dst = *src ^ *iv;
162 		des3_ede_enc_blk(ctx, (u8 *)dst, (u8 *)dst);
163 		iv = dst;
164 
165 		src += 1;
166 		dst += 1;
167 		nbytes -= bsize;
168 	} while (nbytes >= bsize);
169 
170 	*(u64 *)walk->iv = *iv;
171 	return nbytes;
172 }
173 
174 static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
175 		       struct scatterlist *src, unsigned int nbytes)
176 {
177 	struct blkcipher_walk walk;
178 	int err;
179 
180 	blkcipher_walk_init(&walk, dst, src, nbytes);
181 	err = blkcipher_walk_virt(desc, &walk);
182 
183 	while ((nbytes = walk.nbytes)) {
184 		nbytes = __cbc_encrypt(desc, &walk);
185 		err = blkcipher_walk_done(desc, &walk, nbytes);
186 	}
187 
188 	return err;
189 }
190 
191 static unsigned int __cbc_decrypt(struct blkcipher_desc *desc,
192 				  struct blkcipher_walk *walk)
193 {
194 	struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
195 	unsigned int bsize = DES3_EDE_BLOCK_SIZE;
196 	unsigned int nbytes = walk->nbytes;
197 	u64 *src = (u64 *)walk->src.virt.addr;
198 	u64 *dst = (u64 *)walk->dst.virt.addr;
199 	u64 ivs[3 - 1];
200 	u64 last_iv;
201 
202 	/* Start of the last block. */
203 	src += nbytes / bsize - 1;
204 	dst += nbytes / bsize - 1;
205 
206 	last_iv = *src;
207 
208 	/* Process four block batch */
209 	if (nbytes >= bsize * 3) {
210 		do {
211 			nbytes -= bsize * 3 - bsize;
212 			src -= 3 - 1;
213 			dst -= 3 - 1;
214 
215 			ivs[0] = src[0];
216 			ivs[1] = src[1];
217 
218 			des3_ede_dec_blk_3way(ctx, (u8 *)dst, (u8 *)src);
219 
220 			dst[1] ^= ivs[0];
221 			dst[2] ^= ivs[1];
222 
223 			nbytes -= bsize;
224 			if (nbytes < bsize)
225 				goto done;
226 
227 			*dst ^= *(src - 1);
228 			src -= 1;
229 			dst -= 1;
230 		} while (nbytes >= bsize * 3);
231 	}
232 
233 	/* Handle leftovers */
234 	for (;;) {
235 		des3_ede_dec_blk(ctx, (u8 *)dst, (u8 *)src);
236 
237 		nbytes -= bsize;
238 		if (nbytes < bsize)
239 			break;
240 
241 		*dst ^= *(src - 1);
242 		src -= 1;
243 		dst -= 1;
244 	}
245 
246 done:
247 	*dst ^= *(u64 *)walk->iv;
248 	*(u64 *)walk->iv = last_iv;
249 
250 	return nbytes;
251 }
252 
253 static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
254 		       struct scatterlist *src, unsigned int nbytes)
255 {
256 	struct blkcipher_walk walk;
257 	int err;
258 
259 	blkcipher_walk_init(&walk, dst, src, nbytes);
260 	err = blkcipher_walk_virt(desc, &walk);
261 
262 	while ((nbytes = walk.nbytes)) {
263 		nbytes = __cbc_decrypt(desc, &walk);
264 		err = blkcipher_walk_done(desc, &walk, nbytes);
265 	}
266 
267 	return err;
268 }
269 
270 static void ctr_crypt_final(struct des3_ede_x86_ctx *ctx,
271 			    struct blkcipher_walk *walk)
272 {
273 	u8 *ctrblk = walk->iv;
274 	u8 keystream[DES3_EDE_BLOCK_SIZE];
275 	u8 *src = walk->src.virt.addr;
276 	u8 *dst = walk->dst.virt.addr;
277 	unsigned int nbytes = walk->nbytes;
278 
279 	des3_ede_enc_blk(ctx, keystream, ctrblk);
280 	crypto_xor(keystream, src, nbytes);
281 	memcpy(dst, keystream, nbytes);
282 
283 	crypto_inc(ctrblk, DES3_EDE_BLOCK_SIZE);
284 }
285 
286 static unsigned int __ctr_crypt(struct blkcipher_desc *desc,
287 				struct blkcipher_walk *walk)
288 {
289 	struct des3_ede_x86_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
290 	unsigned int bsize = DES3_EDE_BLOCK_SIZE;
291 	unsigned int nbytes = walk->nbytes;
292 	__be64 *src = (__be64 *)walk->src.virt.addr;
293 	__be64 *dst = (__be64 *)walk->dst.virt.addr;
294 	u64 ctrblk = be64_to_cpu(*(__be64 *)walk->iv);
295 	__be64 ctrblocks[3];
296 
297 	/* Process four block batch */
298 	if (nbytes >= bsize * 3) {
299 		do {
300 			/* create ctrblks for parallel encrypt */
301 			ctrblocks[0] = cpu_to_be64(ctrblk++);
302 			ctrblocks[1] = cpu_to_be64(ctrblk++);
303 			ctrblocks[2] = cpu_to_be64(ctrblk++);
304 
305 			des3_ede_enc_blk_3way(ctx, (u8 *)ctrblocks,
306 					      (u8 *)ctrblocks);
307 
308 			dst[0] = src[0] ^ ctrblocks[0];
309 			dst[1] = src[1] ^ ctrblocks[1];
310 			dst[2] = src[2] ^ ctrblocks[2];
311 
312 			src += 3;
313 			dst += 3;
314 		} while ((nbytes -= bsize * 3) >= bsize * 3);
315 
316 		if (nbytes < bsize)
317 			goto done;
318 	}
319 
320 	/* Handle leftovers */
321 	do {
322 		ctrblocks[0] = cpu_to_be64(ctrblk++);
323 
324 		des3_ede_enc_blk(ctx, (u8 *)ctrblocks, (u8 *)ctrblocks);
325 
326 		dst[0] = src[0] ^ ctrblocks[0];
327 
328 		src += 1;
329 		dst += 1;
330 	} while ((nbytes -= bsize) >= bsize);
331 
332 done:
333 	*(__be64 *)walk->iv = cpu_to_be64(ctrblk);
334 	return nbytes;
335 }
336 
337 static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst,
338 		     struct scatterlist *src, unsigned int nbytes)
339 {
340 	struct blkcipher_walk walk;
341 	int err;
342 
343 	blkcipher_walk_init(&walk, dst, src, nbytes);
344 	err = blkcipher_walk_virt_block(desc, &walk, DES3_EDE_BLOCK_SIZE);
345 
346 	while ((nbytes = walk.nbytes) >= DES3_EDE_BLOCK_SIZE) {
347 		nbytes = __ctr_crypt(desc, &walk);
348 		err = blkcipher_walk_done(desc, &walk, nbytes);
349 	}
350 
351 	if (walk.nbytes) {
352 		ctr_crypt_final(crypto_blkcipher_ctx(desc->tfm), &walk);
353 		err = blkcipher_walk_done(desc, &walk, 0);
354 	}
355 
356 	return err;
357 }
358 
359 static int des3_ede_x86_setkey(struct crypto_tfm *tfm, const u8 *key,
360 			       unsigned int keylen)
361 {
362 	struct des3_ede_x86_ctx *ctx = crypto_tfm_ctx(tfm);
363 	u32 i, j, tmp;
364 	int err;
365 
366 	/* Generate encryption context using generic implementation. */
367 	err = __des3_ede_setkey(ctx->enc_expkey, &tfm->crt_flags, key, keylen);
368 	if (err < 0)
369 		return err;
370 
371 	/* Fix encryption context for this implementation and form decryption
372 	 * context. */
373 	j = DES3_EDE_EXPKEY_WORDS - 2;
374 	for (i = 0; i < DES3_EDE_EXPKEY_WORDS; i += 2, j -= 2) {
375 		tmp = ror32(ctx->enc_expkey[i + 1], 4);
376 		ctx->enc_expkey[i + 1] = tmp;
377 
378 		ctx->dec_expkey[j + 0] = ctx->enc_expkey[i + 0];
379 		ctx->dec_expkey[j + 1] = tmp;
380 	}
381 
382 	return 0;
383 }
384 
385 static struct crypto_alg des3_ede_algs[4] = { {
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 	.cra_name		= "ecb(des3_ede)",
405 	.cra_driver_name	= "ecb-des3_ede-asm",
406 	.cra_priority		= 300,
407 	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
408 	.cra_blocksize		= DES3_EDE_BLOCK_SIZE,
409 	.cra_ctxsize		= sizeof(struct des3_ede_x86_ctx),
410 	.cra_alignmask		= 0,
411 	.cra_type		= &crypto_blkcipher_type,
412 	.cra_module		= THIS_MODULE,
413 	.cra_u = {
414 		.blkcipher = {
415 			.min_keysize	= DES3_EDE_KEY_SIZE,
416 			.max_keysize	= DES3_EDE_KEY_SIZE,
417 			.setkey		= des3_ede_x86_setkey,
418 			.encrypt	= ecb_encrypt,
419 			.decrypt	= ecb_decrypt,
420 		},
421 	},
422 }, {
423 	.cra_name		= "cbc(des3_ede)",
424 	.cra_driver_name	= "cbc-des3_ede-asm",
425 	.cra_priority		= 300,
426 	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
427 	.cra_blocksize		= DES3_EDE_BLOCK_SIZE,
428 	.cra_ctxsize		= sizeof(struct des3_ede_x86_ctx),
429 	.cra_alignmask		= 0,
430 	.cra_type		= &crypto_blkcipher_type,
431 	.cra_module		= THIS_MODULE,
432 	.cra_u = {
433 		.blkcipher = {
434 			.min_keysize	= DES3_EDE_KEY_SIZE,
435 			.max_keysize	= DES3_EDE_KEY_SIZE,
436 			.ivsize		= DES3_EDE_BLOCK_SIZE,
437 			.setkey		= des3_ede_x86_setkey,
438 			.encrypt	= cbc_encrypt,
439 			.decrypt	= cbc_decrypt,
440 		},
441 	},
442 }, {
443 	.cra_name		= "ctr(des3_ede)",
444 	.cra_driver_name	= "ctr-des3_ede-asm",
445 	.cra_priority		= 300,
446 	.cra_flags		= CRYPTO_ALG_TYPE_BLKCIPHER,
447 	.cra_blocksize		= 1,
448 	.cra_ctxsize		= sizeof(struct des3_ede_x86_ctx),
449 	.cra_alignmask		= 0,
450 	.cra_type		= &crypto_blkcipher_type,
451 	.cra_module		= THIS_MODULE,
452 	.cra_u = {
453 		.blkcipher = {
454 			.min_keysize	= DES3_EDE_KEY_SIZE,
455 			.max_keysize	= DES3_EDE_KEY_SIZE,
456 			.ivsize		= DES3_EDE_BLOCK_SIZE,
457 			.setkey		= des3_ede_x86_setkey,
458 			.encrypt	= ctr_crypt,
459 			.decrypt	= ctr_crypt,
460 		},
461 	},
462 } };
463 
464 static bool is_blacklisted_cpu(void)
465 {
466 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
467 		return false;
468 
469 	if (boot_cpu_data.x86 == 0x0f) {
470 		/*
471 		 * On Pentium 4, des3_ede-x86_64 is slower than generic C
472 		 * implementation because use of 64bit rotates (which are really
473 		 * slow on P4). Therefore blacklist P4s.
474 		 */
475 		return true;
476 	}
477 
478 	return false;
479 }
480 
481 static int force;
482 module_param(force, int, 0);
483 MODULE_PARM_DESC(force, "Force module load, ignore CPU blacklist");
484 
485 static int __init des3_ede_x86_init(void)
486 {
487 	if (!force && is_blacklisted_cpu()) {
488 		pr_info("des3_ede-x86_64: performance on this CPU would be suboptimal: disabling des3_ede-x86_64.\n");
489 		return -ENODEV;
490 	}
491 
492 	return crypto_register_algs(des3_ede_algs, ARRAY_SIZE(des3_ede_algs));
493 }
494 
495 static void __exit des3_ede_x86_fini(void)
496 {
497 	crypto_unregister_algs(des3_ede_algs, ARRAY_SIZE(des3_ede_algs));
498 }
499 
500 module_init(des3_ede_x86_init);
501 module_exit(des3_ede_x86_fini);
502 
503 MODULE_LICENSE("GPL");
504 MODULE_DESCRIPTION("Triple DES EDE Cipher Algorithm, asm optimized");
505 MODULE_ALIAS_CRYPTO("des3_ede");
506 MODULE_ALIAS_CRYPTO("des3_ede-asm");
507 MODULE_AUTHOR("Jussi Kivilinna <jussi.kivilinna@iki.fi>");
508