1 /* $NetBSD: cgd_crypto.c,v 1.8 2007/12/15 00:39:26 perry 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 1.8 2007/12/15 00:39:26 perry 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(const 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 *, const void *, size_t); 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 *, const void *, size_t); 177 static void aes_cbc_dec_int(void *, void *, const void *, size_t); 178 179 void * 180 cgd_cipher_aes_init(size_t keylen, const void *key, size_t *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 == (size_t)-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 ap; 198 } 199 200 void 201 cgd_cipher_aes_destroy(void *data) 202 { 203 struct aes_privdata *apd = data; 204 205 (void)memset(apd, 0, sizeof(*apd)); 206 free(apd, M_DEVBUF); 207 } 208 209 void 210 aes_cbc_enc_int(void *privdata, void *dst, const void *src, size_t len) 211 { 212 struct aes_encdata *ae = 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 (void)memcpy(ae->ae_iv, (u_int8_t *)dst + (len - 16), 16); 218 } 219 220 void 221 aes_cbc_dec_int(void *privdata, void *dst, const void *src, size_t len) 222 { 223 struct aes_encdata *ae = 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 (void)memcpy(ae->ae_iv, (const u_int8_t *)src + (len - 16), 16); 229 } 230 231 void 232 cgd_cipher_aes_cbc(void *privdata, struct uio *dstuio, 233 struct uio *srcuio, void *iv, int dir) 234 { 235 struct aes_privdata *apd = privdata; 236 struct aes_encdata encd; 237 238 (void)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(("%s: unrecognised direction %d", __func__, dir)); 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 *, const void *, size_t); 276 static void c3des_cbc_dec_int(void *, void *, const void *, size_t); 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 void * 286 cgd_cipher_3des_init(size_t keylen, const void *key, size_t *blocksize) 287 { 288 struct c3des_privdata *cp; 289 int error = 0; 290 des_cblock *block; 291 292 if (!blocksize) 293 return NULL; 294 if (*blocksize == (size_t)-1) 295 *blocksize = 64; 296 if (keylen != (DES_KEY_SZ * 3 * 8) || *blocksize != 64) 297 return NULL; 298 cp = malloc(sizeof(*cp), M_DEVBUF, 0); 299 if (!cp) 300 return NULL; 301 block = __UNCONST(key); 302 error = des_key_sched(block, cp->cp_key1); 303 error |= des_key_sched(block + 1, cp->cp_key2); 304 error |= des_key_sched(block + 2, cp->cp_key3); 305 if (error) { 306 (void)memset(cp, 0, sizeof(*cp)); 307 free(cp, M_DEVBUF); 308 return NULL; 309 } 310 return cp; 311 } 312 313 void 314 cgd_cipher_3des_destroy(void *data) 315 { 316 struct c3des_privdata *cp = data; 317 318 (void)memset(cp, 0, sizeof(*cp)); 319 free(cp, M_DEVBUF); 320 } 321 322 static void 323 c3des_cbc_enc_int(void *privdata, void *dst, const void *src, size_t len) 324 { 325 struct c3des_encdata *ce = privdata; 326 327 des_ede3_cbc_encrypt(src, dst, len, *ce->ce_key1, *ce->ce_key2, 328 *ce->ce_key3, (des_cblock *)ce->ce_iv, 1); 329 (void)memcpy(ce->ce_iv, (const u_int8_t *)dst + (len - 8), 8); 330 } 331 332 static void 333 c3des_cbc_dec_int(void *privdata, void *dst, const void *src, size_t len) 334 { 335 struct c3des_encdata *ce = privdata; 336 337 des_ede3_cbc_encrypt(src, dst, len, *ce->ce_key1, *ce->ce_key2, 338 *ce->ce_key3, (des_cblock *)ce->ce_iv, 0); 339 (void)memcpy(ce->ce_iv, (const u_int8_t *)src + (len - 8), 8); 340 } 341 342 void 343 cgd_cipher_3des_cbc(void *privdata, struct uio *dstuio, 344 struct uio *srcuio, void *iv, int dir) 345 { 346 struct c3des_privdata *cp = privdata; 347 struct c3des_encdata ce; 348 349 (void)memcpy(ce.ce_iv, iv, 8); 350 ce.ce_key1 = &cp->cp_key1; 351 ce.ce_key2 = &cp->cp_key2; 352 ce.ce_key3 = &cp->cp_key3; 353 switch (dir) { 354 case CGD_CIPHER_ENCRYPT: 355 cgd_cipher_uio_cbc(&ce, c3des_cbc_enc_int, dstuio, srcuio); 356 break; 357 case CGD_CIPHER_DECRYPT: 358 cgd_cipher_uio_cbc(&ce, c3des_cbc_dec_int, dstuio, srcuio); 359 break; 360 default: 361 DIAGPANIC(("%s: unrecognised direction %d", __func__, dir)); 362 } 363 } 364 365 /* 366 * Blowfish Framework 367 */ 368 369 #include <crypto/blowfish/blowfish.h> 370 371 cfunc_init cgd_cipher_bf_init; 372 cfunc_destroy cgd_cipher_bf_destroy; 373 cfunc_cipher cgd_cipher_bf_cbc; 374 375 struct cryptfuncs cgd_BF_funcs = { 376 cgd_cipher_bf_init, 377 cgd_cipher_bf_destroy, 378 cgd_cipher_bf_cbc, 379 }; 380 381 static void bf_cbc_enc_int(void *, void *, const void *, size_t); 382 static void bf_cbc_dec_int(void *, void *, const void *, size_t); 383 384 struct bf_privdata { 385 BF_KEY bp_key; 386 }; 387 388 struct bf_encdata { 389 BF_KEY *be_key; 390 u_int8_t be_iv[8]; 391 }; 392 393 void * 394 cgd_cipher_bf_init(size_t keylen, const void *key, size_t *blocksize) 395 { 396 struct bf_privdata *bp; 397 398 if (!blocksize) 399 return NULL; 400 if (keylen < 40 || keylen > 448 || (keylen % 8 != 0)) 401 return NULL; 402 if (*blocksize == (size_t)-1) 403 *blocksize = 64; 404 if (*blocksize != 64) 405 return NULL; 406 bp = malloc(sizeof(*bp), M_DEVBUF, 0); 407 if (!bp) 408 return NULL; 409 BF_set_key(&bp->bp_key, keylen / 8, key); 410 return bp; 411 } 412 413 void 414 cgd_cipher_bf_destroy(void *data) 415 { 416 struct bf_privdata *bp = data; 417 418 (void)memset(bp, 0, sizeof(*bp)); 419 free(bp, M_DEVBUF); 420 } 421 422 void 423 bf_cbc_enc_int(void *privdata, void *dst, const void *src, size_t len) 424 { 425 struct bf_encdata *be = privdata; 426 427 BF_cbc_encrypt(src, dst, len, be->be_key, be->be_iv, 1); 428 (void)memcpy(be->be_iv, (u_int8_t *)dst + (len - 8), 8); 429 } 430 431 void 432 bf_cbc_dec_int(void *privdata, void *dst, const void *src, size_t len) 433 { 434 struct bf_encdata *be = privdata; 435 436 BF_cbc_encrypt(src, dst, len, be->be_key, be->be_iv, 0); 437 (void)memcpy(be->be_iv, (const u_int8_t *)src + (len - 8), 8); 438 } 439 440 void 441 cgd_cipher_bf_cbc(void *privdata, struct uio *dstuio, 442 struct uio *srcuio, void *iv, int dir) 443 { 444 struct bf_privdata *bp = privdata; 445 struct bf_encdata be; 446 447 (void)memcpy(be.be_iv, iv, 8); 448 be.be_key = &bp->bp_key; 449 switch (dir) { 450 case CGD_CIPHER_ENCRYPT: 451 cgd_cipher_uio_cbc(&be, bf_cbc_enc_int, dstuio, srcuio); 452 break; 453 case CGD_CIPHER_DECRYPT: 454 cgd_cipher_uio_cbc(&be, bf_cbc_dec_int, dstuio, srcuio); 455 break; 456 default: 457 DIAGPANIC(("%s: unrecognised direction %d", __func__, dir)); 458 } 459 460 } 461