| 1 | /* $NetBSD: cgd_crypto.c,v 1.13 2015/04/25 12:55:04 riastradh 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 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | /* |
| 33 | * Crypto Framework For cgd.c |
| 34 | * |
| 35 | * This framework is temporary and awaits a more complete |
| 36 | * kernel wide crypto implementation. |
| 37 | */ |
| 38 | |
| 39 | #include <sys/cdefs.h> |
| 40 | __KERNEL_RCSID(0, "$NetBSD: cgd_crypto.c,v 1.13 2015/04/25 12:55:04 riastradh Exp $" ); |
| 41 | |
| 42 | #include <sys/param.h> |
| 43 | #include <sys/systm.h> |
| 44 | #include <sys/malloc.h> |
| 45 | |
| 46 | #include <dev/cgd_crypto.h> |
| 47 | |
| 48 | #include <crypto/rijndael/rijndael-api-fst.h> |
| 49 | #include <crypto/des/des.h> |
| 50 | #include <crypto/blowfish/blowfish.h> |
| 51 | |
| 52 | #ifdef DIAGNOSTIC |
| 53 | #define DIAGPANIC(x) panic x |
| 54 | #else |
| 55 | #define DIAGPANIC(x) |
| 56 | #endif |
| 57 | |
| 58 | /* |
| 59 | * The general framework provides only one generic function. |
| 60 | * It takes the name of an algorith and returns a struct cryptfuncs * |
| 61 | * for it. It is up to the initialisation routines of the algorithm |
| 62 | * to check key size and block size. |
| 63 | */ |
| 64 | |
| 65 | static cfunc_init cgd_cipher_aes_init; |
| 66 | static cfunc_destroy cgd_cipher_aes_destroy; |
| 67 | static cfunc_cipher cgd_cipher_aes_cbc; |
| 68 | |
| 69 | static cfunc_init cgd_cipher_3des_init; |
| 70 | static cfunc_destroy cgd_cipher_3des_destroy; |
| 71 | static cfunc_cipher cgd_cipher_3des_cbc; |
| 72 | |
| 73 | static cfunc_init cgd_cipher_bf_init; |
| 74 | static cfunc_destroy cgd_cipher_bf_destroy; |
| 75 | static cfunc_cipher cgd_cipher_bf_cbc; |
| 76 | |
| 77 | static const struct cryptfuncs cf[] = { |
| 78 | { |
| 79 | .cf_name = "aes-cbc" , |
| 80 | .cf_init = cgd_cipher_aes_init, |
| 81 | .cf_destroy = cgd_cipher_aes_destroy, |
| 82 | .cf_cipher = cgd_cipher_aes_cbc, |
| 83 | }, |
| 84 | { |
| 85 | .cf_name = "3des-cbc" , |
| 86 | .cf_init = cgd_cipher_3des_init, |
| 87 | .cf_destroy = cgd_cipher_3des_destroy, |
| 88 | .cf_cipher = cgd_cipher_3des_cbc, |
| 89 | }, |
| 90 | { |
| 91 | .cf_name = "blowfish-cbc" , |
| 92 | .cf_init = cgd_cipher_bf_init, |
| 93 | .cf_destroy = cgd_cipher_bf_destroy, |
| 94 | .cf_cipher = cgd_cipher_bf_cbc, |
| 95 | }, |
| 96 | }; |
| 97 | const struct cryptfuncs * |
| 98 | cryptfuncs_find(const char *alg) |
| 99 | { |
| 100 | |
| 101 | for (size_t i = 0; i < __arraycount(cf); i++) |
| 102 | if (strcmp(cf[i].cf_name, alg) == 0) |
| 103 | return &cf[i]; |
| 104 | |
| 105 | return NULL; |
| 106 | } |
| 107 | |
| 108 | typedef void (*cipher_func)(void *, void *, const void *, size_t); |
| 109 | |
| 110 | static void |
| 111 | cgd_cipher_uio_cbc(void *privdata, cipher_func cipher, |
| 112 | struct uio *dstuio, struct uio *srcuio); |
| 113 | |
| 114 | /* |
| 115 | * cgd_cipher_uio_cbc takes a simple cbc cipher and iterates |
| 116 | * it over two struct uio's. It presumes that the cipher function |
| 117 | * that is passed to it keeps the IV state between calls. |
| 118 | * |
| 119 | * We assume that the caller has ensured that each segment is evenly |
| 120 | * divisible by the block size, which for the cgd is a valid assumption. |
| 121 | * If we were to make this code more generic, we might need to take care |
| 122 | * of this case, either by issuing an error or copying the data. |
| 123 | */ |
| 124 | |
| 125 | static void |
| 126 | cgd_cipher_uio_cbc(void *privdata, cipher_func cipher, |
| 127 | struct uio *dstuio, struct uio *srcuio) |
| 128 | { |
| 129 | const struct iovec *dst; |
| 130 | const struct iovec *src; |
| 131 | int dstnum; |
| 132 | int dstoff = 0; |
| 133 | int srcnum; |
| 134 | int srcoff = 0; |
| 135 | |
| 136 | dst = dstuio->uio_iov; |
| 137 | dstnum = dstuio->uio_iovcnt; |
| 138 | src = srcuio->uio_iov; |
| 139 | srcnum = srcuio->uio_iovcnt; |
| 140 | for (;;) { |
| 141 | int l = MIN(dst->iov_len - dstoff, src->iov_len - srcoff); |
| 142 | u_int8_t *d = (u_int8_t *)dst->iov_base + dstoff; |
| 143 | const u_int8_t *s = (const u_int8_t *)src->iov_base + srcoff; |
| 144 | |
| 145 | cipher(privdata, d, s, l); |
| 146 | |
| 147 | dstoff += l; |
| 148 | srcoff += l; |
| 149 | /* |
| 150 | * We assume that {dst,src} == {dst,src}->iov_len, |
| 151 | * because it should not be possible for it not to be. |
| 152 | */ |
| 153 | if (dstoff == dst->iov_len) { |
| 154 | dstoff = 0; |
| 155 | dstnum--; |
| 156 | dst++; |
| 157 | } |
| 158 | if (srcoff == src->iov_len) { |
| 159 | srcoff = 0; |
| 160 | srcnum--; |
| 161 | src++; |
| 162 | } |
| 163 | if (!srcnum || !dstnum) |
| 164 | break; |
| 165 | } |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | * AES Framework |
| 170 | */ |
| 171 | |
| 172 | /* |
| 173 | * NOTE: we do not store the blocksize in here, because it is not |
| 174 | * variable [yet], we hardcode the blocksize to 16 (128 bits). |
| 175 | */ |
| 176 | |
| 177 | struct aes_privdata { |
| 178 | keyInstance ap_enckey; |
| 179 | keyInstance ap_deckey; |
| 180 | }; |
| 181 | |
| 182 | struct aes_encdata { |
| 183 | keyInstance *ae_key; /* key for this direction */ |
| 184 | u_int8_t ae_iv[16]; /* Initialization Vector */ |
| 185 | }; |
| 186 | |
| 187 | static void * |
| 188 | cgd_cipher_aes_init(size_t keylen, const void *key, size_t *blocksize) |
| 189 | { |
| 190 | struct aes_privdata *ap; |
| 191 | |
| 192 | if (!blocksize) |
| 193 | return NULL; |
| 194 | if (keylen != 128 && keylen != 192 && keylen != 256) |
| 195 | return NULL; |
| 196 | if (*blocksize == (size_t)-1) |
| 197 | *blocksize = 128; |
| 198 | if (*blocksize != 128) |
| 199 | return NULL; |
| 200 | ap = malloc(sizeof(*ap), M_DEVBUF, 0); |
| 201 | if (!ap) |
| 202 | return NULL; |
| 203 | rijndael_makeKey(&ap->ap_enckey, DIR_ENCRYPT, keylen, key); |
| 204 | rijndael_makeKey(&ap->ap_deckey, DIR_DECRYPT, keylen, key); |
| 205 | return ap; |
| 206 | } |
| 207 | |
| 208 | static void |
| 209 | cgd_cipher_aes_destroy(void *data) |
| 210 | { |
| 211 | struct aes_privdata *apd = data; |
| 212 | |
| 213 | explicit_memset(apd, 0, sizeof(*apd)); |
| 214 | free(apd, M_DEVBUF); |
| 215 | } |
| 216 | |
| 217 | static void |
| 218 | aes_cbc_enc_int(void *privdata, void *dst, const void *src, size_t len) |
| 219 | { |
| 220 | struct aes_encdata *ae = privdata; |
| 221 | cipherInstance cipher; |
| 222 | |
| 223 | rijndael_cipherInit(&cipher, MODE_CBC, ae->ae_iv); |
| 224 | rijndael_blockEncrypt(&cipher, ae->ae_key, src, len * 8, dst); |
| 225 | (void)memcpy(ae->ae_iv, (u_int8_t *)dst + (len - 16), 16); |
| 226 | } |
| 227 | |
| 228 | static void |
| 229 | aes_cbc_dec_int(void *privdata, void *dst, const void *src, size_t len) |
| 230 | { |
| 231 | struct aes_encdata *ae = privdata; |
| 232 | cipherInstance cipher; |
| 233 | |
| 234 | rijndael_cipherInit(&cipher, MODE_CBC, ae->ae_iv); |
| 235 | rijndael_blockDecrypt(&cipher, ae->ae_key, src, len * 8, dst); |
| 236 | (void)memcpy(ae->ae_iv, (const u_int8_t *)src + (len - 16), 16); |
| 237 | } |
| 238 | |
| 239 | static void |
| 240 | cgd_cipher_aes_cbc(void *privdata, struct uio *dstuio, |
| 241 | struct uio *srcuio, const void *iv, int dir) |
| 242 | { |
| 243 | struct aes_privdata *apd = privdata; |
| 244 | struct aes_encdata encd; |
| 245 | |
| 246 | (void)memcpy(encd.ae_iv, iv, 16); |
| 247 | switch (dir) { |
| 248 | case CGD_CIPHER_ENCRYPT: |
| 249 | encd.ae_key = &apd->ap_enckey; |
| 250 | cgd_cipher_uio_cbc(&encd, aes_cbc_enc_int, dstuio, srcuio); |
| 251 | break; |
| 252 | case CGD_CIPHER_DECRYPT: |
| 253 | encd.ae_key = &apd->ap_deckey; |
| 254 | cgd_cipher_uio_cbc(&encd, aes_cbc_dec_int, dstuio, srcuio); |
| 255 | break; |
| 256 | default: |
| 257 | DIAGPANIC(("%s: unrecognised direction %d" , __func__, dir)); |
| 258 | } |
| 259 | } |
| 260 | |
| 261 | /* |
| 262 | * 3DES Framework |
| 263 | */ |
| 264 | |
| 265 | struct c3des_privdata { |
| 266 | des_key_schedule cp_key1; |
| 267 | des_key_schedule cp_key2; |
| 268 | des_key_schedule cp_key3; |
| 269 | }; |
| 270 | |
| 271 | struct c3des_encdata { |
| 272 | des_key_schedule *ce_key1; |
| 273 | des_key_schedule *ce_key2; |
| 274 | des_key_schedule *ce_key3; |
| 275 | u_int8_t ce_iv[8]; |
| 276 | }; |
| 277 | |
| 278 | static void * |
| 279 | cgd_cipher_3des_init(size_t keylen, const void *key, size_t *blocksize) |
| 280 | { |
| 281 | struct c3des_privdata *cp; |
| 282 | int error = 0; |
| 283 | des_cblock *block; |
| 284 | |
| 285 | if (!blocksize) |
| 286 | return NULL; |
| 287 | if (*blocksize == (size_t)-1) |
| 288 | *blocksize = 64; |
| 289 | if (keylen != (DES_KEY_SZ * 3 * 8) || *blocksize != 64) |
| 290 | return NULL; |
| 291 | cp = malloc(sizeof(*cp), M_DEVBUF, 0); |
| 292 | if (!cp) |
| 293 | return NULL; |
| 294 | block = __UNCONST(key); |
| 295 | error = des_key_sched(block, cp->cp_key1); |
| 296 | error |= des_key_sched(block + 1, cp->cp_key2); |
| 297 | error |= des_key_sched(block + 2, cp->cp_key3); |
| 298 | if (error) { |
| 299 | explicit_memset(cp, 0, sizeof(*cp)); |
| 300 | free(cp, M_DEVBUF); |
| 301 | return NULL; |
| 302 | } |
| 303 | return cp; |
| 304 | } |
| 305 | |
| 306 | static void |
| 307 | cgd_cipher_3des_destroy(void *data) |
| 308 | { |
| 309 | struct c3des_privdata *cp = data; |
| 310 | |
| 311 | explicit_memset(cp, 0, sizeof(*cp)); |
| 312 | free(cp, M_DEVBUF); |
| 313 | } |
| 314 | |
| 315 | static void |
| 316 | c3des_cbc_enc_int(void *privdata, void *dst, const void *src, size_t len) |
| 317 | { |
| 318 | struct c3des_encdata *ce = privdata; |
| 319 | |
| 320 | des_ede3_cbc_encrypt(src, dst, len, *ce->ce_key1, *ce->ce_key2, |
| 321 | *ce->ce_key3, (des_cblock *)ce->ce_iv, 1); |
| 322 | (void)memcpy(ce->ce_iv, (const u_int8_t *)dst + (len - 8), 8); |
| 323 | } |
| 324 | |
| 325 | static void |
| 326 | c3des_cbc_dec_int(void *privdata, void *dst, const void *src, size_t len) |
| 327 | { |
| 328 | struct c3des_encdata *ce = privdata; |
| 329 | |
| 330 | des_ede3_cbc_encrypt(src, dst, len, *ce->ce_key1, *ce->ce_key2, |
| 331 | *ce->ce_key3, (des_cblock *)ce->ce_iv, 0); |
| 332 | (void)memcpy(ce->ce_iv, (const u_int8_t *)src + (len - 8), 8); |
| 333 | } |
| 334 | |
| 335 | static void |
| 336 | cgd_cipher_3des_cbc(void *privdata, struct uio *dstuio, |
| 337 | struct uio *srcuio, const void *iv, int dir) |
| 338 | { |
| 339 | struct c3des_privdata *cp = privdata; |
| 340 | struct c3des_encdata ce; |
| 341 | |
| 342 | (void)memcpy(ce.ce_iv, iv, 8); |
| 343 | ce.ce_key1 = &cp->cp_key1; |
| 344 | ce.ce_key2 = &cp->cp_key2; |
| 345 | ce.ce_key3 = &cp->cp_key3; |
| 346 | switch (dir) { |
| 347 | case CGD_CIPHER_ENCRYPT: |
| 348 | cgd_cipher_uio_cbc(&ce, c3des_cbc_enc_int, dstuio, srcuio); |
| 349 | break; |
| 350 | case CGD_CIPHER_DECRYPT: |
| 351 | cgd_cipher_uio_cbc(&ce, c3des_cbc_dec_int, dstuio, srcuio); |
| 352 | break; |
| 353 | default: |
| 354 | DIAGPANIC(("%s: unrecognised direction %d" , __func__, dir)); |
| 355 | } |
| 356 | } |
| 357 | |
| 358 | /* |
| 359 | * Blowfish Framework |
| 360 | */ |
| 361 | |
| 362 | struct bf_privdata { |
| 363 | BF_KEY bp_key; |
| 364 | }; |
| 365 | |
| 366 | struct bf_encdata { |
| 367 | BF_KEY *be_key; |
| 368 | u_int8_t be_iv[8]; |
| 369 | }; |
| 370 | |
| 371 | static void * |
| 372 | cgd_cipher_bf_init(size_t keylen, const void *key, size_t *blocksize) |
| 373 | { |
| 374 | struct bf_privdata *bp; |
| 375 | |
| 376 | if (!blocksize) |
| 377 | return NULL; |
| 378 | if (keylen < 40 || keylen > 448 || (keylen % 8 != 0)) |
| 379 | return NULL; |
| 380 | if (*blocksize == (size_t)-1) |
| 381 | *blocksize = 64; |
| 382 | if (*blocksize != 64) |
| 383 | return NULL; |
| 384 | bp = malloc(sizeof(*bp), M_DEVBUF, 0); |
| 385 | if (!bp) |
| 386 | return NULL; |
| 387 | BF_set_key(&bp->bp_key, keylen / 8, key); |
| 388 | return bp; |
| 389 | } |
| 390 | |
| 391 | static void |
| 392 | cgd_cipher_bf_destroy(void *data) |
| 393 | { |
| 394 | struct bf_privdata *bp = data; |
| 395 | |
| 396 | explicit_memset(bp, 0, sizeof(*bp)); |
| 397 | free(bp, M_DEVBUF); |
| 398 | } |
| 399 | |
| 400 | static void |
| 401 | bf_cbc_enc_int(void *privdata, void *dst, const void *src, size_t len) |
| 402 | { |
| 403 | struct bf_encdata *be = privdata; |
| 404 | |
| 405 | BF_cbc_encrypt(src, dst, len, be->be_key, be->be_iv, 1); |
| 406 | (void)memcpy(be->be_iv, (u_int8_t *)dst + (len - 8), 8); |
| 407 | } |
| 408 | |
| 409 | static void |
| 410 | bf_cbc_dec_int(void *privdata, void *dst, const void *src, size_t len) |
| 411 | { |
| 412 | struct bf_encdata *be = privdata; |
| 413 | |
| 414 | BF_cbc_encrypt(src, dst, len, be->be_key, be->be_iv, 0); |
| 415 | (void)memcpy(be->be_iv, (const u_int8_t *)src + (len - 8), 8); |
| 416 | } |
| 417 | |
| 418 | static void |
| 419 | cgd_cipher_bf_cbc(void *privdata, struct uio *dstuio, |
| 420 | struct uio *srcuio, const void *iv, int dir) |
| 421 | { |
| 422 | struct bf_privdata *bp = privdata; |
| 423 | struct bf_encdata be; |
| 424 | |
| 425 | (void)memcpy(be.be_iv, iv, 8); |
| 426 | be.be_key = &bp->bp_key; |
| 427 | switch (dir) { |
| 428 | case CGD_CIPHER_ENCRYPT: |
| 429 | cgd_cipher_uio_cbc(&be, bf_cbc_enc_int, dstuio, srcuio); |
| 430 | break; |
| 431 | case CGD_CIPHER_DECRYPT: |
| 432 | cgd_cipher_uio_cbc(&be, bf_cbc_dec_int, dstuio, srcuio); |
| 433 | break; |
| 434 | default: |
| 435 | DIAGPANIC(("%s: unrecognised direction %d" , __func__, dir)); |
| 436 | } |
| 437 | |
| 438 | } |
| 439 | |