Kazunori MIYAZAWA | 333b0d7 | 2006-10-28 13:15:24 +1000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C)2006 USAGI/WIDE Project |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 17 | * |
| 18 | * Author: |
| 19 | * Kazunori Miyazawa <miyazawa@linux-ipv6.org> |
| 20 | */ |
| 21 | |
| 22 | #include <linux/crypto.h> |
| 23 | #include <linux/err.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/mm.h> |
| 26 | #include <linux/rtnetlink.h> |
| 27 | #include <linux/slab.h> |
| 28 | #include <linux/scatterlist.h> |
| 29 | #include "internal.h" |
| 30 | |
Adrian Bunk | 5b37538 | 2006-11-17 13:43:04 +1100 | [diff] [blame^] | 31 | static u_int32_t ks[12] = {0x01010101, 0x01010101, 0x01010101, 0x01010101, |
| 32 | 0x02020202, 0x02020202, 0x02020202, 0x02020202, |
| 33 | 0x03030303, 0x03030303, 0x03030303, 0x03030303}; |
Kazunori MIYAZAWA | 333b0d7 | 2006-10-28 13:15:24 +1000 | [diff] [blame] | 34 | /* |
| 35 | * +------------------------ |
| 36 | * | <parent tfm> |
| 37 | * +------------------------ |
| 38 | * | crypto_xcbc_ctx |
| 39 | * +------------------------ |
| 40 | * | odds (block size) |
| 41 | * +------------------------ |
| 42 | * | prev (block size) |
| 43 | * +------------------------ |
| 44 | * | key (block size) |
| 45 | * +------------------------ |
| 46 | * | consts (block size * 3) |
| 47 | * +------------------------ |
| 48 | */ |
| 49 | struct crypto_xcbc_ctx { |
| 50 | struct crypto_tfm *child; |
| 51 | u8 *odds; |
| 52 | u8 *prev; |
| 53 | u8 *key; |
| 54 | u8 *consts; |
| 55 | void (*xor)(u8 *a, const u8 *b, unsigned int bs); |
| 56 | unsigned int keylen; |
| 57 | unsigned int len; |
| 58 | }; |
| 59 | |
| 60 | static void xor_128(u8 *a, const u8 *b, unsigned int bs) |
| 61 | { |
| 62 | ((u32 *)a)[0] ^= ((u32 *)b)[0]; |
| 63 | ((u32 *)a)[1] ^= ((u32 *)b)[1]; |
| 64 | ((u32 *)a)[2] ^= ((u32 *)b)[2]; |
| 65 | ((u32 *)a)[3] ^= ((u32 *)b)[3]; |
| 66 | } |
| 67 | |
| 68 | static int _crypto_xcbc_digest_setkey(struct crypto_hash *parent, |
| 69 | struct crypto_xcbc_ctx *ctx) |
| 70 | { |
| 71 | int bs = crypto_hash_blocksize(parent); |
| 72 | int err = 0; |
| 73 | u8 key1[bs]; |
| 74 | |
| 75 | if ((err = crypto_cipher_setkey(ctx->child, ctx->key, ctx->keylen))) |
| 76 | return err; |
| 77 | |
| 78 | ctx->child->__crt_alg->cra_cipher.cia_encrypt(ctx->child, key1, |
| 79 | ctx->consts); |
| 80 | |
| 81 | return crypto_cipher_setkey(ctx->child, key1, bs); |
| 82 | } |
| 83 | |
| 84 | static int crypto_xcbc_digest_setkey(struct crypto_hash *parent, |
| 85 | const u8 *inkey, unsigned int keylen) |
| 86 | { |
| 87 | struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent); |
| 88 | |
| 89 | if (keylen != crypto_tfm_alg_blocksize(ctx->child)) |
| 90 | return -EINVAL; |
| 91 | |
| 92 | ctx->keylen = keylen; |
| 93 | memcpy(ctx->key, inkey, keylen); |
| 94 | ctx->consts = (u8*)ks; |
| 95 | |
| 96 | return _crypto_xcbc_digest_setkey(parent, ctx); |
| 97 | } |
| 98 | |
Adrian Bunk | 5b37538 | 2006-11-17 13:43:04 +1100 | [diff] [blame^] | 99 | static int crypto_xcbc_digest_init(struct hash_desc *pdesc) |
Kazunori MIYAZAWA | 333b0d7 | 2006-10-28 13:15:24 +1000 | [diff] [blame] | 100 | { |
| 101 | struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(pdesc->tfm); |
| 102 | int bs = crypto_hash_blocksize(pdesc->tfm); |
| 103 | |
| 104 | ctx->len = 0; |
| 105 | memset(ctx->odds, 0, bs); |
| 106 | memset(ctx->prev, 0, bs); |
| 107 | |
| 108 | return 0; |
| 109 | } |
| 110 | |
Adrian Bunk | 5b37538 | 2006-11-17 13:43:04 +1100 | [diff] [blame^] | 111 | static int crypto_xcbc_digest_update(struct hash_desc *pdesc, |
| 112 | struct scatterlist *sg, |
| 113 | unsigned int nbytes) |
Kazunori MIYAZAWA | 333b0d7 | 2006-10-28 13:15:24 +1000 | [diff] [blame] | 114 | { |
| 115 | struct crypto_hash *parent = pdesc->tfm; |
| 116 | struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent); |
| 117 | struct crypto_tfm *tfm = ctx->child; |
| 118 | int bs = crypto_hash_blocksize(parent); |
| 119 | unsigned int i = 0; |
| 120 | |
| 121 | do { |
| 122 | |
| 123 | struct page *pg = sg[i].page; |
| 124 | unsigned int offset = sg[i].offset; |
| 125 | unsigned int slen = sg[i].length; |
| 126 | |
| 127 | while (slen > 0) { |
| 128 | unsigned int len = min(slen, ((unsigned int)(PAGE_SIZE)) - offset); |
| 129 | char *p = crypto_kmap(pg, 0) + offset; |
| 130 | |
| 131 | /* checking the data can fill the block */ |
| 132 | if ((ctx->len + len) <= bs) { |
| 133 | memcpy(ctx->odds + ctx->len, p, len); |
| 134 | ctx->len += len; |
| 135 | slen -= len; |
| 136 | |
| 137 | /* checking the rest of the page */ |
| 138 | if (len + offset >= PAGE_SIZE) { |
| 139 | offset = 0; |
| 140 | pg++; |
| 141 | } else |
| 142 | offset += len; |
| 143 | |
| 144 | crypto_kunmap(p, 0); |
| 145 | crypto_yield(tfm->crt_flags); |
| 146 | continue; |
| 147 | } |
| 148 | |
| 149 | /* filling odds with new data and encrypting it */ |
| 150 | memcpy(ctx->odds + ctx->len, p, bs - ctx->len); |
| 151 | len -= bs - ctx->len; |
| 152 | p += bs - ctx->len; |
| 153 | |
| 154 | ctx->xor(ctx->prev, ctx->odds, bs); |
| 155 | tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, ctx->prev, ctx->prev); |
| 156 | |
| 157 | /* clearing the length */ |
| 158 | ctx->len = 0; |
| 159 | |
| 160 | /* encrypting the rest of data */ |
| 161 | while (len > bs) { |
| 162 | ctx->xor(ctx->prev, p, bs); |
| 163 | tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, ctx->prev, ctx->prev); |
| 164 | p += bs; |
| 165 | len -= bs; |
| 166 | } |
| 167 | |
| 168 | /* keeping the surplus of blocksize */ |
| 169 | if (len) { |
| 170 | memcpy(ctx->odds, p, len); |
| 171 | ctx->len = len; |
| 172 | } |
| 173 | crypto_kunmap(p, 0); |
| 174 | crypto_yield(tfm->crt_flags); |
| 175 | slen -= min(slen, ((unsigned int)(PAGE_SIZE)) - offset); |
| 176 | offset = 0; |
| 177 | pg++; |
| 178 | } |
| 179 | nbytes-=sg[i].length; |
| 180 | i++; |
| 181 | } while (nbytes>0); |
| 182 | |
| 183 | return 0; |
| 184 | } |
| 185 | |
Adrian Bunk | 5b37538 | 2006-11-17 13:43:04 +1100 | [diff] [blame^] | 186 | static int crypto_xcbc_digest_final(struct hash_desc *pdesc, u8 *out) |
Kazunori MIYAZAWA | 333b0d7 | 2006-10-28 13:15:24 +1000 | [diff] [blame] | 187 | { |
| 188 | struct crypto_hash *parent = pdesc->tfm; |
| 189 | struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent); |
| 190 | struct crypto_tfm *tfm = ctx->child; |
| 191 | int bs = crypto_hash_blocksize(parent); |
| 192 | int err = 0; |
| 193 | |
| 194 | if (ctx->len == bs) { |
| 195 | u8 key2[bs]; |
| 196 | |
| 197 | if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0) |
| 198 | return err; |
| 199 | |
| 200 | tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, key2, (const u8*)(ctx->consts+bs)); |
| 201 | |
| 202 | ctx->xor(ctx->prev, ctx->odds, bs); |
| 203 | ctx->xor(ctx->prev, key2, bs); |
| 204 | _crypto_xcbc_digest_setkey(parent, ctx); |
| 205 | |
| 206 | tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, out, ctx->prev); |
| 207 | } else { |
| 208 | u8 key3[bs]; |
| 209 | unsigned int rlen; |
| 210 | u8 *p = ctx->odds + ctx->len; |
| 211 | *p = 0x80; |
| 212 | p++; |
| 213 | |
| 214 | rlen = bs - ctx->len -1; |
| 215 | if (rlen) |
| 216 | memset(p, 0, rlen); |
| 217 | |
| 218 | if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0) |
| 219 | return err; |
| 220 | |
| 221 | tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, key3, (const u8*)(ctx->consts+bs*2)); |
| 222 | |
| 223 | ctx->xor(ctx->prev, ctx->odds, bs); |
| 224 | ctx->xor(ctx->prev, key3, bs); |
| 225 | |
| 226 | _crypto_xcbc_digest_setkey(parent, ctx); |
| 227 | |
| 228 | tfm->__crt_alg->cra_cipher.cia_encrypt(tfm, out, ctx->prev); |
| 229 | } |
| 230 | |
| 231 | return 0; |
| 232 | } |
| 233 | |
| 234 | static int crypto_xcbc_digest(struct hash_desc *pdesc, |
| 235 | struct scatterlist *sg, unsigned int nbytes, u8 *out) |
| 236 | { |
| 237 | crypto_xcbc_digest_init(pdesc); |
| 238 | crypto_xcbc_digest_update(pdesc, sg, nbytes); |
| 239 | return crypto_xcbc_digest_final(pdesc, out); |
| 240 | } |
| 241 | |
| 242 | static int xcbc_init_tfm(struct crypto_tfm *tfm) |
| 243 | { |
| 244 | struct crypto_instance *inst = (void *)tfm->__crt_alg; |
| 245 | struct crypto_spawn *spawn = crypto_instance_ctx(inst); |
| 246 | struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm)); |
| 247 | int bs = crypto_hash_blocksize(__crypto_hash_cast(tfm)); |
| 248 | |
| 249 | tfm = crypto_spawn_tfm(spawn); |
| 250 | if (IS_ERR(tfm)) |
| 251 | return PTR_ERR(tfm); |
| 252 | |
| 253 | switch(bs) { |
| 254 | case 16: |
| 255 | ctx->xor = xor_128; |
| 256 | break; |
| 257 | default: |
| 258 | return -EINVAL; |
| 259 | } |
| 260 | |
| 261 | ctx->child = crypto_cipher_cast(tfm); |
| 262 | ctx->odds = (u8*)(ctx+1); |
| 263 | ctx->prev = ctx->odds + bs; |
| 264 | ctx->key = ctx->prev + bs; |
| 265 | |
| 266 | return 0; |
| 267 | }; |
| 268 | |
| 269 | static void xcbc_exit_tfm(struct crypto_tfm *tfm) |
| 270 | { |
| 271 | struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm)); |
| 272 | crypto_free_cipher(ctx->child); |
| 273 | } |
| 274 | |
| 275 | static struct crypto_instance *xcbc_alloc(void *param, unsigned int len) |
| 276 | { |
| 277 | struct crypto_instance *inst; |
| 278 | struct crypto_alg *alg; |
| 279 | alg = crypto_get_attr_alg(param, len, CRYPTO_ALG_TYPE_CIPHER, |
| 280 | CRYPTO_ALG_TYPE_HASH_MASK | CRYPTO_ALG_ASYNC); |
| 281 | if (IS_ERR(alg)) |
| 282 | return ERR_PTR(PTR_ERR(alg)); |
| 283 | |
| 284 | switch(alg->cra_blocksize) { |
| 285 | case 16: |
| 286 | break; |
| 287 | default: |
| 288 | return ERR_PTR(PTR_ERR(alg)); |
| 289 | } |
| 290 | |
| 291 | inst = crypto_alloc_instance("xcbc", alg); |
| 292 | if (IS_ERR(inst)) |
| 293 | goto out_put_alg; |
| 294 | |
| 295 | inst->alg.cra_flags = CRYPTO_ALG_TYPE_HASH; |
| 296 | inst->alg.cra_priority = alg->cra_priority; |
| 297 | inst->alg.cra_blocksize = alg->cra_blocksize; |
| 298 | inst->alg.cra_alignmask = alg->cra_alignmask; |
| 299 | inst->alg.cra_type = &crypto_hash_type; |
| 300 | |
| 301 | inst->alg.cra_hash.digestsize = |
| 302 | (alg->cra_flags & CRYPTO_ALG_TYPE_MASK) == |
| 303 | CRYPTO_ALG_TYPE_HASH ? alg->cra_hash.digestsize : |
| 304 | alg->cra_blocksize; |
| 305 | inst->alg.cra_ctxsize = sizeof(struct crypto_xcbc_ctx) + |
| 306 | ALIGN(inst->alg.cra_blocksize * 3, sizeof(void *)); |
| 307 | inst->alg.cra_init = xcbc_init_tfm; |
| 308 | inst->alg.cra_exit = xcbc_exit_tfm; |
| 309 | |
| 310 | inst->alg.cra_hash.init = crypto_xcbc_digest_init; |
| 311 | inst->alg.cra_hash.update = crypto_xcbc_digest_update; |
| 312 | inst->alg.cra_hash.final = crypto_xcbc_digest_final; |
| 313 | inst->alg.cra_hash.digest = crypto_xcbc_digest; |
| 314 | inst->alg.cra_hash.setkey = crypto_xcbc_digest_setkey; |
| 315 | |
| 316 | out_put_alg: |
| 317 | crypto_mod_put(alg); |
| 318 | return inst; |
| 319 | } |
| 320 | |
| 321 | static void xcbc_free(struct crypto_instance *inst) |
| 322 | { |
| 323 | crypto_drop_spawn(crypto_instance_ctx(inst)); |
| 324 | kfree(inst); |
| 325 | } |
| 326 | |
| 327 | static struct crypto_template crypto_xcbc_tmpl = { |
| 328 | .name = "xcbc", |
| 329 | .alloc = xcbc_alloc, |
| 330 | .free = xcbc_free, |
| 331 | .module = THIS_MODULE, |
| 332 | }; |
| 333 | |
| 334 | static int __init crypto_xcbc_module_init(void) |
| 335 | { |
| 336 | return crypto_register_template(&crypto_xcbc_tmpl); |
| 337 | } |
| 338 | |
| 339 | static void __exit crypto_xcbc_module_exit(void) |
| 340 | { |
| 341 | crypto_unregister_template(&crypto_xcbc_tmpl); |
| 342 | } |
| 343 | |
| 344 | module_init(crypto_xcbc_module_init); |
| 345 | module_exit(crypto_xcbc_module_exit); |
| 346 | |
| 347 | MODULE_LICENSE("GPL"); |
| 348 | MODULE_DESCRIPTION("XCBC keyed hash algorithm"); |