xref: /netbsd-src/sys/dev/cgd_crypto.c (revision 503611ba29d4c920cb1878a9ece7ebd1e0ac2e16)
1 /* $NetBSD: cgd_crypto.c,v 1.5 2005/12/11 12:20:53 christos Exp $ */
2 
3 /*-
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Roland C. Dowdeswell.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  *  Crypto Framework For cgd.c
41  *
42  *	This framework is temporary and awaits a more complete
43  *	kernel wide crypto implementation.
44  */
45 
46 #include <sys/cdefs.h>
47 __KERNEL_RCSID(0, "$NetBSD: cgd_crypto.c,v 1.5 2005/12/11 12:20:53 christos Exp $");
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/malloc.h>
52 
53 #include <dev/cgd_crypto.h>
54 
55 #ifdef DIAGNOSTIC
56 #define DIAGPANIC(x)	panic(x)
57 #else
58 #define DIAGPANIC(x)
59 #endif
60 
61 /*
62  * The general framework provides only one generic function.
63  * It takes the name of an algorith and returns a struct cryptfuncs *
64  * for it.  It is up to the initialisation routines of the algorithm
65  * to check key size and block size.
66  */
67 
68 extern struct cryptfuncs cgd_AES_funcs;
69 extern struct cryptfuncs cgd_3des_funcs;
70 extern struct cryptfuncs cgd_BF_funcs;
71 
72 struct cryptfuncs *
73 cryptfuncs_find(char *alg)
74 {
75 
76 	if (!strcmp("aes-cbc", alg))
77 		return &cgd_AES_funcs;
78 	if (!strcmp("3des-cbc", alg))
79 		return &cgd_3des_funcs;
80 	if (!strcmp("blowfish-cbc", alg))
81 		return &cgd_BF_funcs;
82 	return NULL;
83 }
84 
85 typedef void	(*cipher_func)(void *, void *, void *, int);
86 
87 void
88 cgd_cipher_uio_cbc(void *privdata, cipher_func cipher,
89 	struct uio *dstuio, struct uio *srcuio);
90 
91 /*
92  * cgd_cipher_uio_cbc takes a simple cbc cipher and iterates
93  * it over two struct uio's.  It presumes that the cipher function
94  * that is passed to it keeps the IV state between calls.
95  *
96  * We assume that the caller has ensured that each segment is evenly
97  * divisible by the block size, which for the cgd is a valid assumption.
98  * If we were to make this code more generic, we might need to take care
99  * of this case, either by issuing an error or copying the data.
100  */
101 
102 void
103 cgd_cipher_uio_cbc(void *privdata, cipher_func cipher,
104 	struct uio *dstuio, struct uio *srcuio)
105 {
106 	struct iovec	*dst;
107 	struct iovec	*src;
108 	int		 dstnum;
109 	int		 dstoff = 0;
110 	int		 srcnum;
111 	int		 srcoff = 0;
112 
113 	dst = dstuio->uio_iov;
114 	dstnum = dstuio->uio_iovcnt;
115 	src = srcuio->uio_iov;
116 	srcnum = srcuio->uio_iovcnt;
117 	for (;;) {
118 		int	  l = MIN(dst->iov_len - dstoff, src->iov_len - srcoff);
119 		u_int8_t *d = (u_int8_t *)dst->iov_base + dstoff;
120 		u_int8_t *s = (u_int8_t *)src->iov_base + srcoff;
121 
122 		cipher(privdata, d, s, l);
123 
124 		dstoff += l;
125 		srcoff += l;
126 		/*
127 		 * We assume that {dst,src} == {dst,src}->iov_len,
128 		 * because it should not be possible for it not to be.
129 		 */
130 		if (dstoff == dst->iov_len) {
131 			dstoff = 0;
132 			dstnum--;
133 			dst++;
134 		}
135 		if (srcoff == src->iov_len) {
136 			srcoff = 0;
137 			srcnum--;
138 			src++;
139 		}
140 		if (!srcnum || !dstnum)
141 			break;
142 	}
143 }
144 
145 /*
146  *  AES Framework
147  */
148 
149 #include <crypto/rijndael/rijndael-api-fst.h>
150 
151 cfunc_init	cgd_cipher_aes_init;
152 cfunc_destroy	cgd_cipher_aes_destroy;
153 cfunc_cipher	cgd_cipher_aes_cbc;
154 
155 struct cryptfuncs cgd_AES_funcs = {
156 	cgd_cipher_aes_init,
157 	cgd_cipher_aes_destroy,
158 	cgd_cipher_aes_cbc,
159 };
160 
161 /*
162  * NOTE: we do not store the blocksize in here, because it is not
163  *       variable [yet], we hardcode the blocksize to 16 (128 bits).
164  */
165 
166 struct aes_privdata {
167 	keyInstance	ap_enckey;
168 	keyInstance	ap_deckey;
169 };
170 
171 struct aes_encdata {
172 	keyInstance	*ae_key;	/* key for this direction */
173 	u_int8_t	 ae_iv[16];	/* Initialization Vector */
174 };
175 
176 static void	aes_cbc_enc_int(void *, void *, void *, int);
177 static void	aes_cbc_dec_int(void *, void *, void *, int);
178 
179 caddr_t
180 cgd_cipher_aes_init(int keylen, caddr_t key, int *blocksize)
181 {
182 	struct	aes_privdata *ap;
183 
184 	if (!blocksize)
185 		return NULL;
186 	if (keylen != 128 && keylen != 192 && keylen != 256)
187 		return NULL;
188 	if (*blocksize == -1)
189 		*blocksize = 128;
190 	if (*blocksize != 128)
191 		return NULL;
192 	ap = malloc(sizeof(*ap), M_DEVBUF, 0);
193 	if (!ap)
194 		return NULL;
195 	rijndael_makeKey(&ap->ap_enckey, DIR_ENCRYPT, keylen, key);
196 	rijndael_makeKey(&ap->ap_deckey, DIR_DECRYPT, keylen, key);
197 	return (caddr_t)ap;
198 }
199 
200 void
201 cgd_cipher_aes_destroy(caddr_t data)
202 {
203 	struct aes_privdata *apd = (void *)data;
204 
205 	memset(apd, 0, sizeof(*apd));
206 	free(apd, M_DEVBUF);
207 }
208 
209 void
210 aes_cbc_enc_int(void *privdata, void *dst, void *src, int len)
211 {
212 	struct aes_encdata	*ae = (void *)privdata;
213 	cipherInstance		 cipher;
214 
215 	rijndael_cipherInit(&cipher, MODE_CBC, ae->ae_iv);
216 	rijndael_blockEncrypt(&cipher, ae->ae_key, src, len * 8, dst);
217 	memcpy(ae->ae_iv, (u_int8_t *)dst + (len - 16), 16);
218 }
219 
220 void
221 aes_cbc_dec_int(void *privdata, void *dst, void *src, int len)
222 {
223 	struct aes_encdata	*ae = (void *)privdata;
224 	cipherInstance		 cipher;
225 
226 	rijndael_cipherInit(&cipher, MODE_CBC, ae->ae_iv);
227 	rijndael_blockDecrypt(&cipher, ae->ae_key, src, len * 8, dst);
228 	memcpy(ae->ae_iv, (u_int8_t *)src + (len - 16), 16);
229 }
230 
231 void
232 cgd_cipher_aes_cbc(caddr_t privdata, struct uio *dstuio,
233 	struct uio *srcuio, caddr_t iv, int dir)
234 {
235 	struct aes_privdata	*apd = (void *)privdata;
236 	struct aes_encdata	 encd;
237 
238 	memcpy(encd.ae_iv, iv, 16);
239 	switch (dir) {
240 	case CGD_CIPHER_ENCRYPT:
241 		encd.ae_key = &apd->ap_enckey;
242 		cgd_cipher_uio_cbc(&encd, aes_cbc_enc_int, dstuio, srcuio);
243 		break;
244 	case CGD_CIPHER_DECRYPT:
245 		encd.ae_key = &apd->ap_deckey;
246 		cgd_cipher_uio_cbc(&encd, aes_cbc_dec_int, dstuio, srcuio);
247 		break;
248 	default:
249 		DIAGPANIC("cgd_cipher_aes_cbc: unrecgnised direction");
250 	}
251 }
252 
253 /*
254  * 3DES Framework
255  */
256 
257 #include <crypto/des/des.h>
258 
259 cfunc_init	cgd_cipher_3des_init;
260 cfunc_destroy	cgd_cipher_3des_destroy;
261 cfunc_cipher	cgd_cipher_3des_cbc;
262 
263 struct cryptfuncs cgd_3des_funcs = {
264 	cgd_cipher_3des_init,
265 	cgd_cipher_3des_destroy,
266 	cgd_cipher_3des_cbc,
267 };
268 
269 struct c3des_privdata {
270 	des_key_schedule	cp_key1;
271 	des_key_schedule	cp_key2;
272 	des_key_schedule	cp_key3;
273 };
274 
275 static void	c3des_cbc_enc_int(void *, void *, void *, int);
276 static void	c3des_cbc_dec_int(void *, void *, void *, int);
277 
278 struct c3des_encdata {
279 	des_key_schedule	*ce_key1;
280 	des_key_schedule	*ce_key2;
281 	des_key_schedule	*ce_key3;
282 	u_int8_t		ce_iv[8];
283 };
284 
285 caddr_t
286 cgd_cipher_3des_init(int keylen, caddr_t key, int *blocksize)
287 {
288 	struct	c3des_privdata *cp;
289 	int	error = 0;
290 
291 	if (!blocksize)
292 		return NULL;
293 	if (*blocksize == -1)
294 		*blocksize = 64;
295 	if (keylen != (DES_KEY_SZ * 3 * 8) || *blocksize != 64)
296 		return NULL;
297 	cp = malloc(sizeof(*cp), M_DEVBUF, 0);
298 	if (!cp)
299 		return NULL;
300 	error  = des_key_sched((des_cblock *)key, cp->cp_key1);
301 	error |= des_key_sched((des_cblock *)key + 1, cp->cp_key2);
302 	error |= des_key_sched((des_cblock *)key + 2, cp->cp_key3);
303 	if (error) {
304 		memset(cp, 0, sizeof(*cp));
305 		free(cp, M_DEVBUF);
306 		return NULL;
307 	}
308 	return (caddr_t)cp;
309 }
310 
311 void
312 cgd_cipher_3des_destroy(caddr_t data)
313 {
314 	struct c3des_privdata *cp = (void *)data;
315 
316 	memset(cp, 0, sizeof(*cp));
317 	free(cp, M_DEVBUF);
318 }
319 
320 static void
321 c3des_cbc_enc_int(void *privdata, void *dst, void *src, int len)
322 {
323 	struct	c3des_encdata *ce = (void *)privdata;
324 
325 	des_ede3_cbc_encrypt(src, dst, len, *ce->ce_key1, *ce->ce_key2,
326 	    *ce->ce_key3, (des_cblock *)ce->ce_iv, 1);
327 	memcpy(ce->ce_iv, (u_int8_t *)dst + (len - 8), 8);
328 }
329 
330 static void
331 c3des_cbc_dec_int(void *privdata, void *dst, void *src, int len)
332 {
333 	struct	c3des_encdata *ce = (void *)privdata;
334 
335 	des_ede3_cbc_encrypt(src, dst, len, *ce->ce_key1, *ce->ce_key2,
336 	    *ce->ce_key3, (des_cblock *)ce->ce_iv, 0);
337 	memcpy(ce->ce_iv, (u_int8_t *)src + (len - 8), 8);
338 }
339 
340 void
341 cgd_cipher_3des_cbc(caddr_t privdata, struct uio *dstuio,
342 	struct uio *srcuio, caddr_t iv, int dir)
343 {
344 	struct	c3des_privdata *cp = (void *)privdata;
345 	struct	c3des_encdata ce;
346 
347 	memcpy(ce.ce_iv, iv, 8);
348 	ce.ce_key1 = &cp->cp_key1;
349 	ce.ce_key2 = &cp->cp_key2;
350 	ce.ce_key3 = &cp->cp_key3;
351 	switch (dir) {
352 	case CGD_CIPHER_ENCRYPT:
353 		cgd_cipher_uio_cbc(&ce, c3des_cbc_enc_int, dstuio, srcuio);
354 		break;
355 	case CGD_CIPHER_DECRYPT:
356 		cgd_cipher_uio_cbc(&ce, c3des_cbc_dec_int, dstuio, srcuio);
357 		break;
358 	default:
359 		DIAGPANIC("cgd_cipher_3des_cbc: unrecognised direction");
360 	}
361 }
362 
363 /*
364  * Blowfish Framework
365  */
366 
367 #include <crypto/blowfish/blowfish.h>
368 
369 cfunc_init	cgd_cipher_bf_init;
370 cfunc_destroy	cgd_cipher_bf_destroy;
371 cfunc_cipher	cgd_cipher_bf_cbc;
372 
373 struct cryptfuncs cgd_BF_funcs = {
374 	cgd_cipher_bf_init,
375 	cgd_cipher_bf_destroy,
376 	cgd_cipher_bf_cbc,
377 };
378 
379 static void	bf_cbc_enc_int(void *, void *, void *, int);
380 static void	bf_cbc_dec_int(void *, void *, void *, int);
381 
382 struct bf_privdata {
383 	BF_KEY	bp_key;
384 };
385 
386 struct bf_encdata {
387 	BF_KEY		*be_key;
388 	u_int8_t	 be_iv[8];
389 };
390 
391 caddr_t
392 cgd_cipher_bf_init(int keylen, caddr_t key, int *blocksize)
393 {
394 	struct	bf_privdata *bp;
395 
396 	if (!blocksize)
397 		return NULL;
398 	if (keylen < 40 || keylen > 448 || (keylen % 8 != 0))
399 		return NULL;
400 	if (*blocksize == -1)
401 		*blocksize = 64;
402 	if (*blocksize != 64)
403 		return NULL;
404 	bp = malloc(sizeof(*bp), M_DEVBUF, 0);
405 	if (!bp)
406 		return NULL;
407 	BF_set_key(&bp->bp_key, keylen / 8, key);
408 	return (caddr_t)bp;
409 }
410 
411 void
412 cgd_cipher_bf_destroy(caddr_t data)
413 {
414 	struct	bf_privdata *bp = (void *)data;
415 
416 	memset(bp, 0, sizeof(*bp));
417 	free(bp, M_DEVBUF);
418 }
419 
420 void
421 bf_cbc_enc_int(void *privdata, void *dst, void *src, int len)
422 {
423 	struct	bf_encdata *be = (void *)privdata;
424 
425 	BF_cbc_encrypt(src, dst, len, be->be_key, be->be_iv, 1);
426 	memcpy(be->be_iv, (u_int8_t *)dst + (len - 8), 8);
427 }
428 
429 void
430 bf_cbc_dec_int(void *privdata, void *dst, void *src, int len)
431 {
432 	struct	bf_encdata *be = (void *)privdata;
433 
434 	BF_cbc_encrypt(src, dst, len, be->be_key, be->be_iv, 0);
435 	memcpy(be->be_iv, (u_int8_t *)src + (len - 8), 8);
436 }
437 
438 void
439 cgd_cipher_bf_cbc(caddr_t privdata, struct uio *dstuio,
440 	struct uio *srcuio, caddr_t iv, int dir)
441 {
442 	struct	bf_privdata *bp = (void *)privdata;
443 	struct	bf_encdata be;
444 
445 	memcpy(be.be_iv, iv, 8);
446 	be.be_key = &bp->bp_key;
447 	switch (dir) {
448 	case CGD_CIPHER_ENCRYPT:
449 		cgd_cipher_uio_cbc(&be, bf_cbc_enc_int, dstuio, srcuio);
450 		break;
451 	case CGD_CIPHER_DECRYPT:
452 		cgd_cipher_uio_cbc(&be, bf_cbc_dec_int, dstuio, srcuio);
453 		break;
454 	default:
455 		DIAGPANIC("cgd_cipher_bf_cbc: unrecognised direction");
456 	}
457 
458 }
459