Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 1 | /* |
| 2 | * PRNG: Pseudo Random Number Generator |
| 3 | * Based on NIST Recommended PRNG From ANSI X9.31 Appendix A.2.4 using |
| 4 | * AES 128 cipher |
| 5 | * |
| 6 | * (C) Neil Horman <nhorman@tuxdriver.com> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify it |
| 9 | * under the terms of the GNU General Public License as published by the |
| 10 | * Free Software Foundation; either version 2 of the License, or (at your |
| 11 | * any later version. |
| 12 | * |
| 13 | * |
| 14 | */ |
| 15 | |
| 16 | #include <crypto/internal/rng.h> |
| 17 | #include <linux/err.h> |
| 18 | #include <linux/init.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/moduleparam.h> |
| 21 | #include <linux/string.h> |
| 22 | |
| 23 | #include "internal.h" |
| 24 | |
| 25 | #define DEFAULT_PRNG_KEY "0123456789abcdef" |
| 26 | #define DEFAULT_PRNG_KSZ 16 |
| 27 | #define DEFAULT_BLK_SZ 16 |
| 28 | #define DEFAULT_V_SEED "zaybxcwdveuftgsh" |
| 29 | |
| 30 | /* |
| 31 | * Flags for the prng_context flags field |
| 32 | */ |
| 33 | |
| 34 | #define PRNG_FIXED_SIZE 0x1 |
| 35 | #define PRNG_NEED_RESET 0x2 |
| 36 | |
| 37 | /* |
| 38 | * Note: DT is our counter value |
| 39 | * I is our intermediate value |
| 40 | * V is our seed vector |
| 41 | * See http://csrc.nist.gov/groups/STM/cavp/documents/rng/931rngext.pdf |
| 42 | * for implementation details |
| 43 | */ |
| 44 | |
| 45 | |
| 46 | struct prng_context { |
| 47 | spinlock_t prng_lock; |
| 48 | unsigned char rand_data[DEFAULT_BLK_SZ]; |
| 49 | unsigned char last_rand_data[DEFAULT_BLK_SZ]; |
| 50 | unsigned char DT[DEFAULT_BLK_SZ]; |
| 51 | unsigned char I[DEFAULT_BLK_SZ]; |
| 52 | unsigned char V[DEFAULT_BLK_SZ]; |
| 53 | u32 rand_data_valid; |
| 54 | struct crypto_cipher *tfm; |
| 55 | u32 flags; |
| 56 | }; |
| 57 | |
| 58 | static int dbg; |
| 59 | |
| 60 | static void hexdump(char *note, unsigned char *buf, unsigned int len) |
| 61 | { |
| 62 | if (dbg) { |
| 63 | printk(KERN_CRIT "%s", note); |
| 64 | print_hex_dump(KERN_CONT, "", DUMP_PREFIX_OFFSET, |
| 65 | 16, 1, |
| 66 | buf, len, false); |
| 67 | } |
| 68 | } |
| 69 | |
| 70 | #define dbgprint(format, args...) do {\ |
| 71 | if (dbg)\ |
| 72 | printk(format, ##args);\ |
| 73 | } while (0) |
| 74 | |
| 75 | static void xor_vectors(unsigned char *in1, unsigned char *in2, |
| 76 | unsigned char *out, unsigned int size) |
| 77 | { |
| 78 | int i; |
| 79 | |
| 80 | for (i = 0; i < size; i++) |
| 81 | out[i] = in1[i] ^ in2[i]; |
| 82 | |
| 83 | } |
| 84 | /* |
| 85 | * Returns DEFAULT_BLK_SZ bytes of random data per call |
| 86 | * returns 0 if generation succeded, <0 if something went wrong |
| 87 | */ |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 88 | static int _get_more_prng_bytes(struct prng_context *ctx, int cont_test) |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 89 | { |
| 90 | int i; |
| 91 | unsigned char tmp[DEFAULT_BLK_SZ]; |
| 92 | unsigned char *output = NULL; |
| 93 | |
| 94 | |
| 95 | dbgprint(KERN_CRIT "Calling _get_more_prng_bytes for context %p\n", |
| 96 | ctx); |
| 97 | |
| 98 | hexdump("Input DT: ", ctx->DT, DEFAULT_BLK_SZ); |
| 99 | hexdump("Input I: ", ctx->I, DEFAULT_BLK_SZ); |
| 100 | hexdump("Input V: ", ctx->V, DEFAULT_BLK_SZ); |
| 101 | |
| 102 | /* |
| 103 | * This algorithm is a 3 stage state machine |
| 104 | */ |
| 105 | for (i = 0; i < 3; i++) { |
| 106 | |
| 107 | switch (i) { |
| 108 | case 0: |
| 109 | /* |
| 110 | * Start by encrypting the counter value |
| 111 | * This gives us an intermediate value I |
| 112 | */ |
| 113 | memcpy(tmp, ctx->DT, DEFAULT_BLK_SZ); |
| 114 | output = ctx->I; |
| 115 | hexdump("tmp stage 0: ", tmp, DEFAULT_BLK_SZ); |
| 116 | break; |
| 117 | case 1: |
| 118 | |
| 119 | /* |
| 120 | * Next xor I with our secret vector V |
| 121 | * encrypt that result to obtain our |
| 122 | * pseudo random data which we output |
| 123 | */ |
| 124 | xor_vectors(ctx->I, ctx->V, tmp, DEFAULT_BLK_SZ); |
| 125 | hexdump("tmp stage 1: ", tmp, DEFAULT_BLK_SZ); |
| 126 | output = ctx->rand_data; |
| 127 | break; |
| 128 | case 2: |
| 129 | /* |
| 130 | * First check that we didn't produce the same |
| 131 | * random data that we did last time around through this |
| 132 | */ |
| 133 | if (!memcmp(ctx->rand_data, ctx->last_rand_data, |
| 134 | DEFAULT_BLK_SZ)) { |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 135 | if (cont_test) { |
Neil Horman | c5b1e54 | 2009-02-05 16:01:38 +1100 | [diff] [blame] | 136 | panic("cprng %p Failed repetition check!\n", |
| 137 | ctx); |
| 138 | } |
| 139 | |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 140 | printk(KERN_ERR |
| 141 | "ctx %p Failed repetition check!\n", |
| 142 | ctx); |
Neil Horman | c5b1e54 | 2009-02-05 16:01:38 +1100 | [diff] [blame] | 143 | |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 144 | ctx->flags |= PRNG_NEED_RESET; |
| 145 | return -EINVAL; |
| 146 | } |
| 147 | memcpy(ctx->last_rand_data, ctx->rand_data, |
| 148 | DEFAULT_BLK_SZ); |
| 149 | |
| 150 | /* |
| 151 | * Lastly xor the random data with I |
| 152 | * and encrypt that to obtain a new secret vector V |
| 153 | */ |
| 154 | xor_vectors(ctx->rand_data, ctx->I, tmp, |
| 155 | DEFAULT_BLK_SZ); |
| 156 | output = ctx->V; |
| 157 | hexdump("tmp stage 2: ", tmp, DEFAULT_BLK_SZ); |
| 158 | break; |
| 159 | } |
| 160 | |
| 161 | |
| 162 | /* do the encryption */ |
| 163 | crypto_cipher_encrypt_one(ctx->tfm, output, tmp); |
| 164 | |
| 165 | } |
| 166 | |
| 167 | /* |
| 168 | * Now update our DT value |
| 169 | */ |
Jarod Wilson | 09fbf7c | 2008-11-24 21:20:13 +0800 | [diff] [blame] | 170 | for (i = DEFAULT_BLK_SZ - 1; i >= 0; i--) { |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 171 | ctx->DT[i] += 1; |
| 172 | if (ctx->DT[i] != 0) |
| 173 | break; |
| 174 | } |
| 175 | |
| 176 | dbgprint("Returning new block for context %p\n", ctx); |
| 177 | ctx->rand_data_valid = 0; |
| 178 | |
| 179 | hexdump("Output DT: ", ctx->DT, DEFAULT_BLK_SZ); |
| 180 | hexdump("Output I: ", ctx->I, DEFAULT_BLK_SZ); |
| 181 | hexdump("Output V: ", ctx->V, DEFAULT_BLK_SZ); |
| 182 | hexdump("New Random Data: ", ctx->rand_data, DEFAULT_BLK_SZ); |
| 183 | |
| 184 | return 0; |
| 185 | } |
| 186 | |
| 187 | /* Our exported functions */ |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 188 | static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx, |
| 189 | int do_cont_test) |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 190 | { |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 191 | unsigned char *ptr = buf; |
| 192 | unsigned int byte_count = (unsigned int)nbytes; |
| 193 | int err; |
| 194 | |
| 195 | |
Sebastian Andrzej Siewior | ed94070 | 2009-07-03 12:09:41 +0800 | [diff] [blame] | 196 | spin_lock_bh(&ctx->prng_lock); |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 197 | |
| 198 | err = -EINVAL; |
| 199 | if (ctx->flags & PRNG_NEED_RESET) |
| 200 | goto done; |
| 201 | |
| 202 | /* |
| 203 | * If the FIXED_SIZE flag is on, only return whole blocks of |
| 204 | * pseudo random data |
| 205 | */ |
| 206 | err = -EINVAL; |
| 207 | if (ctx->flags & PRNG_FIXED_SIZE) { |
| 208 | if (nbytes < DEFAULT_BLK_SZ) |
| 209 | goto done; |
| 210 | byte_count = DEFAULT_BLK_SZ; |
| 211 | } |
| 212 | |
| 213 | err = byte_count; |
| 214 | |
| 215 | dbgprint(KERN_CRIT "getting %d random bytes for context %p\n", |
| 216 | byte_count, ctx); |
| 217 | |
| 218 | |
| 219 | remainder: |
| 220 | if (ctx->rand_data_valid == DEFAULT_BLK_SZ) { |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 221 | if (_get_more_prng_bytes(ctx, do_cont_test) < 0) { |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 222 | memset(buf, 0, nbytes); |
| 223 | err = -EINVAL; |
| 224 | goto done; |
| 225 | } |
| 226 | } |
| 227 | |
| 228 | /* |
Jarod Wilson | aa1a85d | 2008-11-13 22:03:20 +0800 | [diff] [blame] | 229 | * Copy any data less than an entire block |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 230 | */ |
| 231 | if (byte_count < DEFAULT_BLK_SZ) { |
Jarod Wilson | aa1a85d | 2008-11-13 22:03:20 +0800 | [diff] [blame] | 232 | empty_rbuf: |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 233 | for (; ctx->rand_data_valid < DEFAULT_BLK_SZ; |
| 234 | ctx->rand_data_valid++) { |
| 235 | *ptr = ctx->rand_data[ctx->rand_data_valid]; |
| 236 | ptr++; |
| 237 | byte_count--; |
| 238 | if (byte_count == 0) |
| 239 | goto done; |
| 240 | } |
| 241 | } |
| 242 | |
| 243 | /* |
| 244 | * Now copy whole blocks |
| 245 | */ |
| 246 | for (; byte_count >= DEFAULT_BLK_SZ; byte_count -= DEFAULT_BLK_SZ) { |
Jarod Wilson | aa1a85d | 2008-11-13 22:03:20 +0800 | [diff] [blame] | 247 | if (ctx->rand_data_valid == DEFAULT_BLK_SZ) { |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 248 | if (_get_more_prng_bytes(ctx, do_cont_test) < 0) { |
Jarod Wilson | aa1a85d | 2008-11-13 22:03:20 +0800 | [diff] [blame] | 249 | memset(buf, 0, nbytes); |
| 250 | err = -EINVAL; |
| 251 | goto done; |
| 252 | } |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 253 | } |
Jarod Wilson | aa1a85d | 2008-11-13 22:03:20 +0800 | [diff] [blame] | 254 | if (ctx->rand_data_valid > 0) |
| 255 | goto empty_rbuf; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 256 | memcpy(ptr, ctx->rand_data, DEFAULT_BLK_SZ); |
| 257 | ctx->rand_data_valid += DEFAULT_BLK_SZ; |
| 258 | ptr += DEFAULT_BLK_SZ; |
| 259 | } |
| 260 | |
| 261 | /* |
Jarod Wilson | aa1a85d | 2008-11-13 22:03:20 +0800 | [diff] [blame] | 262 | * Now go back and get any remaining partial block |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 263 | */ |
| 264 | if (byte_count) |
| 265 | goto remainder; |
| 266 | |
| 267 | done: |
Sebastian Andrzej Siewior | ed94070 | 2009-07-03 12:09:41 +0800 | [diff] [blame] | 268 | spin_unlock_bh(&ctx->prng_lock); |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 269 | dbgprint(KERN_CRIT "returning %d from get_prng_bytes in context %p\n", |
| 270 | err, ctx); |
| 271 | return err; |
| 272 | } |
| 273 | |
| 274 | static void free_prng_context(struct prng_context *ctx) |
| 275 | { |
| 276 | crypto_free_cipher(ctx->tfm); |
| 277 | } |
| 278 | |
| 279 | static int reset_prng_context(struct prng_context *ctx, |
| 280 | unsigned char *key, size_t klen, |
| 281 | unsigned char *V, unsigned char *DT) |
| 282 | { |
| 283 | int ret; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 284 | unsigned char *prng_key; |
| 285 | |
Sebastian Andrzej Siewior | ed94070 | 2009-07-03 12:09:41 +0800 | [diff] [blame] | 286 | spin_lock_bh(&ctx->prng_lock); |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 287 | ctx->flags |= PRNG_NEED_RESET; |
| 288 | |
| 289 | prng_key = (key != NULL) ? key : (unsigned char *)DEFAULT_PRNG_KEY; |
| 290 | |
| 291 | if (!key) |
| 292 | klen = DEFAULT_PRNG_KSZ; |
| 293 | |
| 294 | if (V) |
| 295 | memcpy(ctx->V, V, DEFAULT_BLK_SZ); |
| 296 | else |
| 297 | memcpy(ctx->V, DEFAULT_V_SEED, DEFAULT_BLK_SZ); |
| 298 | |
| 299 | if (DT) |
| 300 | memcpy(ctx->DT, DT, DEFAULT_BLK_SZ); |
| 301 | else |
| 302 | memset(ctx->DT, 0, DEFAULT_BLK_SZ); |
| 303 | |
| 304 | memset(ctx->rand_data, 0, DEFAULT_BLK_SZ); |
| 305 | memset(ctx->last_rand_data, 0, DEFAULT_BLK_SZ); |
| 306 | |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 307 | ctx->rand_data_valid = DEFAULT_BLK_SZ; |
| 308 | |
| 309 | ret = crypto_cipher_setkey(ctx->tfm, prng_key, klen); |
| 310 | if (ret) { |
| 311 | dbgprint(KERN_CRIT "PRNG: setkey() failed flags=%x\n", |
| 312 | crypto_cipher_get_flags(ctx->tfm)); |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 313 | goto out; |
| 314 | } |
| 315 | |
Sebastian Andrzej Siewior | fd09d7f | 2009-07-03 12:10:47 +0800 | [diff] [blame] | 316 | ret = 0; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 317 | ctx->flags &= ~PRNG_NEED_RESET; |
| 318 | out: |
Sebastian Andrzej Siewior | ed94070 | 2009-07-03 12:09:41 +0800 | [diff] [blame] | 319 | spin_unlock_bh(&ctx->prng_lock); |
Sebastian Andrzej Siewior | fd09d7f | 2009-07-03 12:10:47 +0800 | [diff] [blame] | 320 | return ret; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 321 | } |
| 322 | |
| 323 | static int cprng_init(struct crypto_tfm *tfm) |
| 324 | { |
| 325 | struct prng_context *ctx = crypto_tfm_ctx(tfm); |
| 326 | |
| 327 | spin_lock_init(&ctx->prng_lock); |
Sebastian Andrzej Siewior | fd09d7f | 2009-07-03 12:10:47 +0800 | [diff] [blame] | 328 | ctx->tfm = crypto_alloc_cipher("aes", 0, 0); |
| 329 | if (IS_ERR(ctx->tfm)) { |
| 330 | dbgprint(KERN_CRIT "Failed to alloc tfm for context %p\n", |
| 331 | ctx); |
| 332 | return PTR_ERR(ctx->tfm); |
| 333 | } |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 334 | |
Neil Horman | d7992f4 | 2009-01-28 15:20:51 +1100 | [diff] [blame] | 335 | if (reset_prng_context(ctx, NULL, DEFAULT_PRNG_KSZ, NULL, NULL) < 0) |
| 336 | return -EINVAL; |
| 337 | |
| 338 | /* |
| 339 | * after allocation, we should always force the user to reset |
| 340 | * so they don't inadvertently use the insecure default values |
| 341 | * without specifying them intentially |
| 342 | */ |
| 343 | ctx->flags |= PRNG_NEED_RESET; |
| 344 | return 0; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 345 | } |
| 346 | |
| 347 | static void cprng_exit(struct crypto_tfm *tfm) |
| 348 | { |
| 349 | free_prng_context(crypto_tfm_ctx(tfm)); |
| 350 | } |
| 351 | |
| 352 | static int cprng_get_random(struct crypto_rng *tfm, u8 *rdata, |
| 353 | unsigned int dlen) |
| 354 | { |
| 355 | struct prng_context *prng = crypto_rng_ctx(tfm); |
| 356 | |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 357 | return get_prng_bytes(rdata, dlen, prng, 0); |
| 358 | } |
| 359 | |
Neil Horman | 2566578 | 2008-11-05 12:13:14 +0800 | [diff] [blame] | 360 | /* |
| 361 | * This is the cprng_registered reset method the seed value is |
| 362 | * interpreted as the tuple { V KEY DT} |
| 363 | * V and KEY are required during reset, and DT is optional, detected |
| 364 | * as being present by testing the length of the seed |
| 365 | */ |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 366 | static int cprng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen) |
| 367 | { |
| 368 | struct prng_context *prng = crypto_rng_ctx(tfm); |
Neil Horman | 2566578 | 2008-11-05 12:13:14 +0800 | [diff] [blame] | 369 | u8 *key = seed + DEFAULT_BLK_SZ; |
| 370 | u8 *dt = NULL; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 371 | |
| 372 | if (slen < DEFAULT_PRNG_KSZ + DEFAULT_BLK_SZ) |
| 373 | return -EINVAL; |
| 374 | |
Neil Horman | 2566578 | 2008-11-05 12:13:14 +0800 | [diff] [blame] | 375 | if (slen >= (2 * DEFAULT_BLK_SZ + DEFAULT_PRNG_KSZ)) |
| 376 | dt = key + DEFAULT_PRNG_KSZ; |
| 377 | |
| 378 | reset_prng_context(prng, key, DEFAULT_PRNG_KSZ, seed, dt); |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 379 | |
| 380 | if (prng->flags & PRNG_NEED_RESET) |
| 381 | return -EINVAL; |
| 382 | return 0; |
| 383 | } |
| 384 | |
| 385 | static struct crypto_alg rng_alg = { |
| 386 | .cra_name = "stdrng", |
| 387 | .cra_driver_name = "ansi_cprng", |
| 388 | .cra_priority = 100, |
| 389 | .cra_flags = CRYPTO_ALG_TYPE_RNG, |
| 390 | .cra_ctxsize = sizeof(struct prng_context), |
| 391 | .cra_type = &crypto_rng_type, |
| 392 | .cra_module = THIS_MODULE, |
| 393 | .cra_list = LIST_HEAD_INIT(rng_alg.cra_list), |
| 394 | .cra_init = cprng_init, |
| 395 | .cra_exit = cprng_exit, |
| 396 | .cra_u = { |
| 397 | .rng = { |
| 398 | .rng_make_random = cprng_get_random, |
| 399 | .rng_reset = cprng_reset, |
Neil Horman | 2566578 | 2008-11-05 12:13:14 +0800 | [diff] [blame] | 400 | .seedsize = DEFAULT_PRNG_KSZ + 2*DEFAULT_BLK_SZ, |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 401 | } |
| 402 | } |
| 403 | }; |
| 404 | |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 405 | #ifdef CONFIG_CRYPTO_FIPS |
Jaswinder Singh Rajput | 2f32bfd8 | 2009-11-23 20:25:50 +0800 | [diff] [blame] | 406 | static int fips_cprng_get_random(struct crypto_rng *tfm, u8 *rdata, |
| 407 | unsigned int dlen) |
| 408 | { |
| 409 | struct prng_context *prng = crypto_rng_ctx(tfm); |
| 410 | |
| 411 | return get_prng_bytes(rdata, dlen, prng, 1); |
| 412 | } |
| 413 | |
| 414 | static int fips_cprng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen) |
| 415 | { |
| 416 | u8 rdata[DEFAULT_BLK_SZ]; |
| 417 | int rc; |
| 418 | |
| 419 | struct prng_context *prng = crypto_rng_ctx(tfm); |
| 420 | |
| 421 | rc = cprng_reset(tfm, seed, slen); |
| 422 | |
| 423 | if (!rc) |
| 424 | goto out; |
| 425 | |
| 426 | /* this primes our continuity test */ |
| 427 | rc = get_prng_bytes(rdata, DEFAULT_BLK_SZ, prng, 0); |
| 428 | prng->rand_data_valid = DEFAULT_BLK_SZ; |
| 429 | |
| 430 | out: |
| 431 | return rc; |
| 432 | } |
| 433 | |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 434 | static struct crypto_alg fips_rng_alg = { |
| 435 | .cra_name = "fips(ansi_cprng)", |
| 436 | .cra_driver_name = "fips_ansi_cprng", |
| 437 | .cra_priority = 300, |
| 438 | .cra_flags = CRYPTO_ALG_TYPE_RNG, |
| 439 | .cra_ctxsize = sizeof(struct prng_context), |
| 440 | .cra_type = &crypto_rng_type, |
| 441 | .cra_module = THIS_MODULE, |
| 442 | .cra_list = LIST_HEAD_INIT(rng_alg.cra_list), |
| 443 | .cra_init = cprng_init, |
| 444 | .cra_exit = cprng_exit, |
| 445 | .cra_u = { |
| 446 | .rng = { |
| 447 | .rng_make_random = fips_cprng_get_random, |
| 448 | .rng_reset = fips_cprng_reset, |
| 449 | .seedsize = DEFAULT_PRNG_KSZ + 2*DEFAULT_BLK_SZ, |
| 450 | } |
| 451 | } |
| 452 | }; |
| 453 | #endif |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 454 | |
| 455 | /* Module initalization */ |
| 456 | static int __init prng_mod_init(void) |
| 457 | { |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 458 | int rc = 0; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 459 | |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 460 | rc = crypto_register_alg(&rng_alg); |
| 461 | #ifdef CONFIG_CRYPTO_FIPS |
| 462 | if (rc) |
| 463 | goto out; |
| 464 | |
| 465 | rc = crypto_register_alg(&fips_rng_alg); |
| 466 | |
| 467 | out: |
| 468 | #endif |
| 469 | return rc; |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 470 | } |
| 471 | |
| 472 | static void __exit prng_mod_fini(void) |
| 473 | { |
| 474 | crypto_unregister_alg(&rng_alg); |
Neil Horman | 667b629 | 2009-10-19 11:57:02 +0900 | [diff] [blame] | 475 | #ifdef CONFIG_CRYPTO_FIPS |
| 476 | crypto_unregister_alg(&fips_rng_alg); |
| 477 | #endif |
Neil Horman | 17f0f4a | 2008-08-14 22:15:52 +1000 | [diff] [blame] | 478 | return; |
| 479 | } |
| 480 | |
| 481 | MODULE_LICENSE("GPL"); |
| 482 | MODULE_DESCRIPTION("Software Pseudo Random Number Generator"); |
| 483 | MODULE_AUTHOR("Neil Horman <nhorman@tuxdriver.com>"); |
| 484 | module_param(dbg, int, 0); |
| 485 | MODULE_PARM_DESC(dbg, "Boolean to enable debugging (0/1 == off/on)"); |
| 486 | module_init(prng_mod_init); |
| 487 | module_exit(prng_mod_fini); |
| 488 | MODULE_ALIAS("stdrng"); |