xref: /openbmc/linux/arch/s390/crypto/des_s390.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Cryptographic API.
3  *
4  * s390 implementation of the DES Cipher Algorithm.
5  *
6  * Copyright IBM Corp. 2003,2007
7  * Author(s): Thomas Spatzier
8  *	      Jan Glauber (jan.glauber@de.ibm.com)
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  */
16 
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/crypto.h>
20 #include <crypto/algapi.h>
21 #include <crypto/des.h>
22 
23 #include "crypt_s390.h"
24 
25 #define DES3_192_KEY_SIZE	(3 * DES_KEY_SIZE)
26 
27 struct crypt_s390_des_ctx {
28 	u8 iv[DES_BLOCK_SIZE];
29 	u8 key[DES_KEY_SIZE];
30 };
31 
32 struct crypt_s390_des3_192_ctx {
33 	u8 iv[DES_BLOCK_SIZE];
34 	u8 key[DES3_192_KEY_SIZE];
35 };
36 
37 static int des_setkey(struct crypto_tfm *tfm, const u8 *key,
38 		      unsigned int keylen)
39 {
40 	struct crypt_s390_des_ctx *dctx = crypto_tfm_ctx(tfm);
41 	u32 *flags = &tfm->crt_flags;
42 	u32 tmp[DES_EXPKEY_WORDS];
43 
44 	/* check for weak keys */
45 	if (!des_ekey(tmp, key) && (*flags & CRYPTO_TFM_REQ_WEAK_KEY)) {
46 		*flags |= CRYPTO_TFM_RES_WEAK_KEY;
47 		return -EINVAL;
48 	}
49 
50 	memcpy(dctx->key, key, keylen);
51 	return 0;
52 }
53 
54 static void des_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
55 {
56 	struct crypt_s390_des_ctx *dctx = crypto_tfm_ctx(tfm);
57 
58 	crypt_s390_km(KM_DEA_ENCRYPT, dctx->key, out, in, DES_BLOCK_SIZE);
59 }
60 
61 static void des_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
62 {
63 	struct crypt_s390_des_ctx *dctx = crypto_tfm_ctx(tfm);
64 
65 	crypt_s390_km(KM_DEA_DECRYPT, dctx->key, out, in, DES_BLOCK_SIZE);
66 }
67 
68 static struct crypto_alg des_alg = {
69 	.cra_name		=	"des",
70 	.cra_driver_name	=	"des-s390",
71 	.cra_priority		=	CRYPT_S390_PRIORITY,
72 	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
73 	.cra_blocksize		=	DES_BLOCK_SIZE,
74 	.cra_ctxsize		=	sizeof(struct crypt_s390_des_ctx),
75 	.cra_module		=	THIS_MODULE,
76 	.cra_list		=	LIST_HEAD_INIT(des_alg.cra_list),
77 	.cra_u			=	{
78 		.cipher = {
79 			.cia_min_keysize	=	DES_KEY_SIZE,
80 			.cia_max_keysize	=	DES_KEY_SIZE,
81 			.cia_setkey		=	des_setkey,
82 			.cia_encrypt		=	des_encrypt,
83 			.cia_decrypt		=	des_decrypt,
84 		}
85 	}
86 };
87 
88 static int ecb_desall_crypt(struct blkcipher_desc *desc, long func,
89 			    void *param, struct blkcipher_walk *walk)
90 {
91 	int ret = blkcipher_walk_virt(desc, walk);
92 	unsigned int nbytes;
93 
94 	while ((nbytes = walk->nbytes)) {
95 		/* only use complete blocks */
96 		unsigned int n = nbytes & ~(DES_BLOCK_SIZE - 1);
97 		u8 *out = walk->dst.virt.addr;
98 		u8 *in = walk->src.virt.addr;
99 
100 		ret = crypt_s390_km(func, param, out, in, n);
101 		BUG_ON((ret < 0) || (ret != n));
102 
103 		nbytes &= DES_BLOCK_SIZE - 1;
104 		ret = blkcipher_walk_done(desc, walk, nbytes);
105 	}
106 
107 	return ret;
108 }
109 
110 static int cbc_desall_crypt(struct blkcipher_desc *desc, long func,
111 			    void *param, struct blkcipher_walk *walk)
112 {
113 	int ret = blkcipher_walk_virt(desc, walk);
114 	unsigned int nbytes = walk->nbytes;
115 
116 	if (!nbytes)
117 		goto out;
118 
119 	memcpy(param, walk->iv, DES_BLOCK_SIZE);
120 	do {
121 		/* only use complete blocks */
122 		unsigned int n = nbytes & ~(DES_BLOCK_SIZE - 1);
123 		u8 *out = walk->dst.virt.addr;
124 		u8 *in = walk->src.virt.addr;
125 
126 		ret = crypt_s390_kmc(func, param, out, in, n);
127 		BUG_ON((ret < 0) || (ret != n));
128 
129 		nbytes &= DES_BLOCK_SIZE - 1;
130 		ret = blkcipher_walk_done(desc, walk, nbytes);
131 	} while ((nbytes = walk->nbytes));
132 	memcpy(walk->iv, param, DES_BLOCK_SIZE);
133 
134 out:
135 	return ret;
136 }
137 
138 static int ecb_des_encrypt(struct blkcipher_desc *desc,
139 			   struct scatterlist *dst, struct scatterlist *src,
140 			   unsigned int nbytes)
141 {
142 	struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
143 	struct blkcipher_walk walk;
144 
145 	blkcipher_walk_init(&walk, dst, src, nbytes);
146 	return ecb_desall_crypt(desc, KM_DEA_ENCRYPT, sctx->key, &walk);
147 }
148 
149 static int ecb_des_decrypt(struct blkcipher_desc *desc,
150 			   struct scatterlist *dst, struct scatterlist *src,
151 			   unsigned int nbytes)
152 {
153 	struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
154 	struct blkcipher_walk walk;
155 
156 	blkcipher_walk_init(&walk, dst, src, nbytes);
157 	return ecb_desall_crypt(desc, KM_DEA_DECRYPT, sctx->key, &walk);
158 }
159 
160 static struct crypto_alg ecb_des_alg = {
161 	.cra_name		=	"ecb(des)",
162 	.cra_driver_name	=	"ecb-des-s390",
163 	.cra_priority		=	CRYPT_S390_COMPOSITE_PRIORITY,
164 	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
165 	.cra_blocksize		=	DES_BLOCK_SIZE,
166 	.cra_ctxsize		=	sizeof(struct crypt_s390_des_ctx),
167 	.cra_type		=	&crypto_blkcipher_type,
168 	.cra_module		=	THIS_MODULE,
169 	.cra_list		=	LIST_HEAD_INIT(ecb_des_alg.cra_list),
170 	.cra_u			=	{
171 		.blkcipher = {
172 			.min_keysize		=	DES_KEY_SIZE,
173 			.max_keysize		=	DES_KEY_SIZE,
174 			.setkey			=	des_setkey,
175 			.encrypt		=	ecb_des_encrypt,
176 			.decrypt		=	ecb_des_decrypt,
177 		}
178 	}
179 };
180 
181 static int cbc_des_encrypt(struct blkcipher_desc *desc,
182 			   struct scatterlist *dst, struct scatterlist *src,
183 			   unsigned int nbytes)
184 {
185 	struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
186 	struct blkcipher_walk walk;
187 
188 	blkcipher_walk_init(&walk, dst, src, nbytes);
189 	return cbc_desall_crypt(desc, KMC_DEA_ENCRYPT, sctx->iv, &walk);
190 }
191 
192 static int cbc_des_decrypt(struct blkcipher_desc *desc,
193 			   struct scatterlist *dst, struct scatterlist *src,
194 			   unsigned int nbytes)
195 {
196 	struct crypt_s390_des_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
197 	struct blkcipher_walk walk;
198 
199 	blkcipher_walk_init(&walk, dst, src, nbytes);
200 	return cbc_desall_crypt(desc, KMC_DEA_DECRYPT, sctx->iv, &walk);
201 }
202 
203 static struct crypto_alg cbc_des_alg = {
204 	.cra_name		=	"cbc(des)",
205 	.cra_driver_name	=	"cbc-des-s390",
206 	.cra_priority		=	CRYPT_S390_COMPOSITE_PRIORITY,
207 	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
208 	.cra_blocksize		=	DES_BLOCK_SIZE,
209 	.cra_ctxsize		=	sizeof(struct crypt_s390_des_ctx),
210 	.cra_type		=	&crypto_blkcipher_type,
211 	.cra_module		=	THIS_MODULE,
212 	.cra_list		=	LIST_HEAD_INIT(cbc_des_alg.cra_list),
213 	.cra_u			=	{
214 		.blkcipher = {
215 			.min_keysize		=	DES_KEY_SIZE,
216 			.max_keysize		=	DES_KEY_SIZE,
217 			.ivsize			=	DES_BLOCK_SIZE,
218 			.setkey			=	des_setkey,
219 			.encrypt		=	cbc_des_encrypt,
220 			.decrypt		=	cbc_des_decrypt,
221 		}
222 	}
223 };
224 
225 /*
226  * RFC2451:
227  *
228  *   For DES-EDE3, there is no known need to reject weak or
229  *   complementation keys.  Any weakness is obviated by the use of
230  *   multiple keys.
231  *
232  *   However, if the first two or last two independent 64-bit keys are
233  *   equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
234  *   same as DES.  Implementers MUST reject keys that exhibit this
235  *   property.
236  *
237  */
238 static int des3_192_setkey(struct crypto_tfm *tfm, const u8 *key,
239 			   unsigned int keylen)
240 {
241 	struct crypt_s390_des3_192_ctx *dctx = crypto_tfm_ctx(tfm);
242 	u32 *flags = &tfm->crt_flags;
243 
244 	if (!(memcmp(key, &key[DES_KEY_SIZE], DES_KEY_SIZE) &&
245 	    memcmp(&key[DES_KEY_SIZE], &key[DES_KEY_SIZE * 2],
246 		   DES_KEY_SIZE)) &&
247 	    (*flags & CRYPTO_TFM_REQ_WEAK_KEY)) {
248 		*flags |= CRYPTO_TFM_RES_WEAK_KEY;
249 		return -EINVAL;
250 	}
251 	memcpy(dctx->key, key, keylen);
252 	return 0;
253 }
254 
255 static void des3_192_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
256 {
257 	struct crypt_s390_des3_192_ctx *dctx = crypto_tfm_ctx(tfm);
258 
259 	crypt_s390_km(KM_TDEA_192_ENCRYPT, dctx->key, dst, (void*)src,
260 		      DES_BLOCK_SIZE);
261 }
262 
263 static void des3_192_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
264 {
265 	struct crypt_s390_des3_192_ctx *dctx = crypto_tfm_ctx(tfm);
266 
267 	crypt_s390_km(KM_TDEA_192_DECRYPT, dctx->key, dst, (void*)src,
268 		      DES_BLOCK_SIZE);
269 }
270 
271 static struct crypto_alg des3_192_alg = {
272 	.cra_name		=	"des3_ede",
273 	.cra_driver_name	=	"des3_ede-s390",
274 	.cra_priority		=	CRYPT_S390_PRIORITY,
275 	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
276 	.cra_blocksize		=	DES_BLOCK_SIZE,
277 	.cra_ctxsize		=	sizeof(struct crypt_s390_des3_192_ctx),
278 	.cra_module		=	THIS_MODULE,
279 	.cra_list		=	LIST_HEAD_INIT(des3_192_alg.cra_list),
280 	.cra_u			=	{
281 		.cipher = {
282 			.cia_min_keysize	=	DES3_192_KEY_SIZE,
283 			.cia_max_keysize	=	DES3_192_KEY_SIZE,
284 			.cia_setkey		=	des3_192_setkey,
285 			.cia_encrypt		=	des3_192_encrypt,
286 			.cia_decrypt		=	des3_192_decrypt,
287 		}
288 	}
289 };
290 
291 static int ecb_des3_192_encrypt(struct blkcipher_desc *desc,
292 				struct scatterlist *dst,
293 				struct scatterlist *src, unsigned int nbytes)
294 {
295 	struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
296 	struct blkcipher_walk walk;
297 
298 	blkcipher_walk_init(&walk, dst, src, nbytes);
299 	return ecb_desall_crypt(desc, KM_TDEA_192_ENCRYPT, sctx->key, &walk);
300 }
301 
302 static int ecb_des3_192_decrypt(struct blkcipher_desc *desc,
303 				struct scatterlist *dst,
304 				struct scatterlist *src, unsigned int nbytes)
305 {
306 	struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
307 	struct blkcipher_walk walk;
308 
309 	blkcipher_walk_init(&walk, dst, src, nbytes);
310 	return ecb_desall_crypt(desc, KM_TDEA_192_DECRYPT, sctx->key, &walk);
311 }
312 
313 static struct crypto_alg ecb_des3_192_alg = {
314 	.cra_name		=	"ecb(des3_ede)",
315 	.cra_driver_name	=	"ecb-des3_ede-s390",
316 	.cra_priority		=	CRYPT_S390_COMPOSITE_PRIORITY,
317 	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
318 	.cra_blocksize		=	DES_BLOCK_SIZE,
319 	.cra_ctxsize		=	sizeof(struct crypt_s390_des3_192_ctx),
320 	.cra_type		=	&crypto_blkcipher_type,
321 	.cra_module		=	THIS_MODULE,
322 	.cra_list		=	LIST_HEAD_INIT(
323 						ecb_des3_192_alg.cra_list),
324 	.cra_u			=	{
325 		.blkcipher = {
326 			.min_keysize		=	DES3_192_KEY_SIZE,
327 			.max_keysize		=	DES3_192_KEY_SIZE,
328 			.setkey			=	des3_192_setkey,
329 			.encrypt		=	ecb_des3_192_encrypt,
330 			.decrypt		=	ecb_des3_192_decrypt,
331 		}
332 	}
333 };
334 
335 static int cbc_des3_192_encrypt(struct blkcipher_desc *desc,
336 				struct scatterlist *dst,
337 				struct scatterlist *src, unsigned int nbytes)
338 {
339 	struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
340 	struct blkcipher_walk walk;
341 
342 	blkcipher_walk_init(&walk, dst, src, nbytes);
343 	return cbc_desall_crypt(desc, KMC_TDEA_192_ENCRYPT, sctx->iv, &walk);
344 }
345 
346 static int cbc_des3_192_decrypt(struct blkcipher_desc *desc,
347 				struct scatterlist *dst,
348 				struct scatterlist *src, unsigned int nbytes)
349 {
350 	struct crypt_s390_des3_192_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
351 	struct blkcipher_walk walk;
352 
353 	blkcipher_walk_init(&walk, dst, src, nbytes);
354 	return cbc_desall_crypt(desc, KMC_TDEA_192_DECRYPT, sctx->iv, &walk);
355 }
356 
357 static struct crypto_alg cbc_des3_192_alg = {
358 	.cra_name		=	"cbc(des3_ede)",
359 	.cra_driver_name	=	"cbc-des3_ede-s390",
360 	.cra_priority		=	CRYPT_S390_COMPOSITE_PRIORITY,
361 	.cra_flags		=	CRYPTO_ALG_TYPE_BLKCIPHER,
362 	.cra_blocksize		=	DES_BLOCK_SIZE,
363 	.cra_ctxsize		=	sizeof(struct crypt_s390_des3_192_ctx),
364 	.cra_type		=	&crypto_blkcipher_type,
365 	.cra_module		=	THIS_MODULE,
366 	.cra_list		=	LIST_HEAD_INIT(
367 						cbc_des3_192_alg.cra_list),
368 	.cra_u			=	{
369 		.blkcipher = {
370 			.min_keysize		=	DES3_192_KEY_SIZE,
371 			.max_keysize		=	DES3_192_KEY_SIZE,
372 			.ivsize			=	DES_BLOCK_SIZE,
373 			.setkey			=	des3_192_setkey,
374 			.encrypt		=	cbc_des3_192_encrypt,
375 			.decrypt		=	cbc_des3_192_decrypt,
376 		}
377 	}
378 };
379 
380 static int des_s390_init(void)
381 {
382 	int ret;
383 
384 	if (!crypt_s390_func_available(KM_DEA_ENCRYPT) ||
385 	    !crypt_s390_func_available(KM_TDEA_192_ENCRYPT))
386 		return -EOPNOTSUPP;
387 
388 	ret = crypto_register_alg(&des_alg);
389 	if (ret)
390 		goto des_err;
391 	ret = crypto_register_alg(&ecb_des_alg);
392 	if (ret)
393 		goto ecb_des_err;
394 	ret = crypto_register_alg(&cbc_des_alg);
395 	if (ret)
396 		goto cbc_des_err;
397 	ret = crypto_register_alg(&des3_192_alg);
398 	if (ret)
399 		goto des3_192_err;
400 	ret = crypto_register_alg(&ecb_des3_192_alg);
401 	if (ret)
402 		goto ecb_des3_192_err;
403 	ret = crypto_register_alg(&cbc_des3_192_alg);
404 	if (ret)
405 		goto cbc_des3_192_err;
406 out:
407 	return ret;
408 
409 cbc_des3_192_err:
410 	crypto_unregister_alg(&ecb_des3_192_alg);
411 ecb_des3_192_err:
412 	crypto_unregister_alg(&des3_192_alg);
413 des3_192_err:
414 	crypto_unregister_alg(&cbc_des_alg);
415 cbc_des_err:
416 	crypto_unregister_alg(&ecb_des_alg);
417 ecb_des_err:
418 	crypto_unregister_alg(&des_alg);
419 des_err:
420 	goto out;
421 }
422 
423 static void __exit des_s390_exit(void)
424 {
425 	crypto_unregister_alg(&cbc_des3_192_alg);
426 	crypto_unregister_alg(&ecb_des3_192_alg);
427 	crypto_unregister_alg(&des3_192_alg);
428 	crypto_unregister_alg(&cbc_des_alg);
429 	crypto_unregister_alg(&ecb_des_alg);
430 	crypto_unregister_alg(&des_alg);
431 }
432 
433 module_init(des_s390_init);
434 module_exit(des_s390_exit);
435 
436 MODULE_ALIAS("des");
437 MODULE_ALIAS("des3_ede");
438 
439 MODULE_LICENSE("GPL");
440 MODULE_DESCRIPTION("DES & Triple DES EDE Cipher Algorithms");
441