1 // SPDX-License-Identifier: GPL-2.0-or-later << 2 /* 1 /* 3 * PRNG: Pseudo Random Number Generator 2 * PRNG: Pseudo Random Number Generator 4 * Based on NIST Recommended PRNG From A 3 * Based on NIST Recommended PRNG From ANSI X9.31 Appendix A.2.4 using 5 * AES 128 cipher 4 * AES 128 cipher 6 * 5 * 7 * (C) Neil Horman <nhorman@tuxdriver.com> 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 * 8 */ 14 */ 9 15 10 #include <crypto/internal/cipher.h> << 11 #include <crypto/internal/rng.h> 16 #include <crypto/internal/rng.h> 12 #include <linux/err.h> 17 #include <linux/err.h> 13 #include <linux/init.h> 18 #include <linux/init.h> 14 #include <linux/module.h> 19 #include <linux/module.h> 15 #include <linux/moduleparam.h> 20 #include <linux/moduleparam.h> 16 #include <linux/string.h> 21 #include <linux/string.h> 17 22 18 #define DEFAULT_PRNG_KEY "0123456789abcdef" 23 #define DEFAULT_PRNG_KEY "0123456789abcdef" 19 #define DEFAULT_PRNG_KSZ 16 24 #define DEFAULT_PRNG_KSZ 16 20 #define DEFAULT_BLK_SZ 16 25 #define DEFAULT_BLK_SZ 16 21 #define DEFAULT_V_SEED "zaybxcwdveuftgsh" 26 #define DEFAULT_V_SEED "zaybxcwdveuftgsh" 22 27 23 /* 28 /* 24 * Flags for the prng_context flags field 29 * Flags for the prng_context flags field 25 */ 30 */ 26 31 27 #define PRNG_FIXED_SIZE 0x1 32 #define PRNG_FIXED_SIZE 0x1 28 #define PRNG_NEED_RESET 0x2 33 #define PRNG_NEED_RESET 0x2 29 34 30 /* 35 /* 31 * Note: DT is our counter value 36 * Note: DT is our counter value 32 * I is our intermediate value 37 * I is our intermediate value 33 * V is our seed vector 38 * V is our seed vector 34 * See http://csrc.nist.gov/groups/STM/cavp/do 39 * See http://csrc.nist.gov/groups/STM/cavp/documents/rng/931rngext.pdf 35 * for implementation details 40 * for implementation details 36 */ 41 */ 37 42 38 43 39 struct prng_context { 44 struct prng_context { 40 spinlock_t prng_lock; 45 spinlock_t prng_lock; 41 unsigned char rand_data[DEFAULT_BLK_SZ 46 unsigned char rand_data[DEFAULT_BLK_SZ]; 42 unsigned char last_rand_data[DEFAULT_B 47 unsigned char last_rand_data[DEFAULT_BLK_SZ]; 43 unsigned char DT[DEFAULT_BLK_SZ]; 48 unsigned char DT[DEFAULT_BLK_SZ]; 44 unsigned char I[DEFAULT_BLK_SZ]; 49 unsigned char I[DEFAULT_BLK_SZ]; 45 unsigned char V[DEFAULT_BLK_SZ]; 50 unsigned char V[DEFAULT_BLK_SZ]; 46 u32 rand_data_valid; 51 u32 rand_data_valid; 47 struct crypto_cipher *tfm; 52 struct crypto_cipher *tfm; 48 u32 flags; 53 u32 flags; 49 }; 54 }; 50 55 51 static int dbg; 56 static int dbg; 52 57 53 static void hexdump(char *note, unsigned char 58 static void hexdump(char *note, unsigned char *buf, unsigned int len) 54 { 59 { 55 if (dbg) { 60 if (dbg) { 56 printk(KERN_CRIT "%s", note); 61 printk(KERN_CRIT "%s", note); 57 print_hex_dump(KERN_CONT, "", 62 print_hex_dump(KERN_CONT, "", DUMP_PREFIX_OFFSET, 58 16, 1, 63 16, 1, 59 buf, len, fals 64 buf, len, false); 60 } 65 } 61 } 66 } 62 67 63 #define dbgprint(format, args...) do {\ 68 #define dbgprint(format, args...) do {\ 64 if (dbg)\ 69 if (dbg)\ 65 printk(format, ##args);\ 70 printk(format, ##args);\ 66 } while (0) 71 } while (0) 67 72 68 static void xor_vectors(unsigned char *in1, un 73 static void xor_vectors(unsigned char *in1, unsigned char *in2, 69 unsigned char *out, un 74 unsigned char *out, unsigned int size) 70 { 75 { 71 int i; 76 int i; 72 77 73 for (i = 0; i < size; i++) 78 for (i = 0; i < size; i++) 74 out[i] = in1[i] ^ in2[i]; 79 out[i] = in1[i] ^ in2[i]; 75 80 76 } 81 } 77 /* 82 /* 78 * Returns DEFAULT_BLK_SZ bytes of random data 83 * Returns DEFAULT_BLK_SZ bytes of random data per call 79 * returns 0 if generation succeeded, <0 if so 84 * returns 0 if generation succeeded, <0 if something went wrong 80 */ 85 */ 81 static int _get_more_prng_bytes(struct prng_co 86 static int _get_more_prng_bytes(struct prng_context *ctx, int cont_test) 82 { 87 { 83 int i; 88 int i; 84 unsigned char tmp[DEFAULT_BLK_SZ]; 89 unsigned char tmp[DEFAULT_BLK_SZ]; 85 unsigned char *output = NULL; 90 unsigned char *output = NULL; 86 91 87 92 88 dbgprint(KERN_CRIT "Calling _get_more_ 93 dbgprint(KERN_CRIT "Calling _get_more_prng_bytes for context %p\n", 89 ctx); 94 ctx); 90 95 91 hexdump("Input DT: ", ctx->DT, DEFAULT 96 hexdump("Input DT: ", ctx->DT, DEFAULT_BLK_SZ); 92 hexdump("Input I: ", ctx->I, DEFAULT_B 97 hexdump("Input I: ", ctx->I, DEFAULT_BLK_SZ); 93 hexdump("Input V: ", ctx->V, DEFAULT_B 98 hexdump("Input V: ", ctx->V, DEFAULT_BLK_SZ); 94 99 95 /* 100 /* 96 * This algorithm is a 3 stage state m 101 * This algorithm is a 3 stage state machine 97 */ 102 */ 98 for (i = 0; i < 3; i++) { 103 for (i = 0; i < 3; i++) { 99 104 100 switch (i) { 105 switch (i) { 101 case 0: 106 case 0: 102 /* 107 /* 103 * Start by encrypting 108 * Start by encrypting the counter value 104 * This gives us an in 109 * This gives us an intermediate value I 105 */ 110 */ 106 memcpy(tmp, ctx->DT, D 111 memcpy(tmp, ctx->DT, DEFAULT_BLK_SZ); 107 output = ctx->I; 112 output = ctx->I; 108 hexdump("tmp stage 0: 113 hexdump("tmp stage 0: ", tmp, DEFAULT_BLK_SZ); 109 break; 114 break; 110 case 1: 115 case 1: 111 116 112 /* 117 /* 113 * Next xor I with our 118 * Next xor I with our secret vector V 114 * encrypt that result 119 * encrypt that result to obtain our 115 * pseudo random data 120 * pseudo random data which we output 116 */ 121 */ 117 xor_vectors(ctx->I, ct 122 xor_vectors(ctx->I, ctx->V, tmp, DEFAULT_BLK_SZ); 118 hexdump("tmp stage 1: 123 hexdump("tmp stage 1: ", tmp, DEFAULT_BLK_SZ); 119 output = ctx->rand_dat 124 output = ctx->rand_data; 120 break; 125 break; 121 case 2: 126 case 2: 122 /* 127 /* 123 * First check that we 128 * First check that we didn't produce the same 124 * random data that we 129 * random data that we did last time around through this 125 */ 130 */ 126 if (!memcmp(ctx->rand_ 131 if (!memcmp(ctx->rand_data, ctx->last_rand_data, 127 DEFAUL 132 DEFAULT_BLK_SZ)) { 128 if (cont_test) 133 if (cont_test) { 129 panic( 134 panic("cprng %p Failed repetition check!\n", 130 135 ctx); 131 } 136 } 132 137 133 printk(KERN_ER 138 printk(KERN_ERR 134 "ctx % 139 "ctx %p Failed repetition check!\n", 135 ctx); 140 ctx); 136 141 137 ctx->flags |= 142 ctx->flags |= PRNG_NEED_RESET; 138 return -EINVAL 143 return -EINVAL; 139 } 144 } 140 memcpy(ctx->last_rand_ 145 memcpy(ctx->last_rand_data, ctx->rand_data, 141 DEFAULT_BLK_SZ 146 DEFAULT_BLK_SZ); 142 147 143 /* 148 /* 144 * Lastly xor the rand 149 * Lastly xor the random data with I 145 * and encrypt that to 150 * and encrypt that to obtain a new secret vector V 146 */ 151 */ 147 xor_vectors(ctx->rand_ 152 xor_vectors(ctx->rand_data, ctx->I, tmp, 148 DEFAULT_BLK_SZ 153 DEFAULT_BLK_SZ); 149 output = ctx->V; 154 output = ctx->V; 150 hexdump("tmp stage 2: 155 hexdump("tmp stage 2: ", tmp, DEFAULT_BLK_SZ); 151 break; 156 break; 152 } 157 } 153 158 154 159 155 /* do the encryption */ 160 /* do the encryption */ 156 crypto_cipher_encrypt_one(ctx- 161 crypto_cipher_encrypt_one(ctx->tfm, output, tmp); 157 162 158 } 163 } 159 164 160 /* 165 /* 161 * Now update our DT value 166 * Now update our DT value 162 */ 167 */ 163 for (i = DEFAULT_BLK_SZ - 1; i >= 0; i 168 for (i = DEFAULT_BLK_SZ - 1; i >= 0; i--) { 164 ctx->DT[i] += 1; 169 ctx->DT[i] += 1; 165 if (ctx->DT[i] != 0) 170 if (ctx->DT[i] != 0) 166 break; 171 break; 167 } 172 } 168 173 169 dbgprint("Returning new block for cont 174 dbgprint("Returning new block for context %p\n", ctx); 170 ctx->rand_data_valid = 0; 175 ctx->rand_data_valid = 0; 171 176 172 hexdump("Output DT: ", ctx->DT, DEFAUL 177 hexdump("Output DT: ", ctx->DT, DEFAULT_BLK_SZ); 173 hexdump("Output I: ", ctx->I, DEFAULT_ 178 hexdump("Output I: ", ctx->I, DEFAULT_BLK_SZ); 174 hexdump("Output V: ", ctx->V, DEFAULT_ 179 hexdump("Output V: ", ctx->V, DEFAULT_BLK_SZ); 175 hexdump("New Random Data: ", ctx->rand 180 hexdump("New Random Data: ", ctx->rand_data, DEFAULT_BLK_SZ); 176 181 177 return 0; 182 return 0; 178 } 183 } 179 184 180 /* Our exported functions */ 185 /* Our exported functions */ 181 static int get_prng_bytes(char *buf, size_t nb 186 static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx, 182 int do_cont_te 187 int do_cont_test) 183 { 188 { 184 unsigned char *ptr = buf; 189 unsigned char *ptr = buf; 185 unsigned int byte_count = (unsigned in 190 unsigned int byte_count = (unsigned int)nbytes; 186 int err; 191 int err; 187 192 188 193 189 spin_lock_bh(&ctx->prng_lock); 194 spin_lock_bh(&ctx->prng_lock); 190 195 191 err = -EINVAL; 196 err = -EINVAL; 192 if (ctx->flags & PRNG_NEED_RESET) 197 if (ctx->flags & PRNG_NEED_RESET) 193 goto done; 198 goto done; 194 199 195 /* 200 /* 196 * If the FIXED_SIZE flag is on, only 201 * If the FIXED_SIZE flag is on, only return whole blocks of 197 * pseudo random data 202 * pseudo random data 198 */ 203 */ 199 err = -EINVAL; 204 err = -EINVAL; 200 if (ctx->flags & PRNG_FIXED_SIZE) { 205 if (ctx->flags & PRNG_FIXED_SIZE) { 201 if (nbytes < DEFAULT_BLK_SZ) 206 if (nbytes < DEFAULT_BLK_SZ) 202 goto done; 207 goto done; 203 byte_count = DEFAULT_BLK_SZ; 208 byte_count = DEFAULT_BLK_SZ; 204 } 209 } 205 210 206 /* 211 /* 207 * Return 0 in case of success as mand 212 * Return 0 in case of success as mandated by the kernel 208 * crypto API interface definition. 213 * crypto API interface definition. 209 */ 214 */ 210 err = 0; 215 err = 0; 211 216 212 dbgprint(KERN_CRIT "getting %d random 217 dbgprint(KERN_CRIT "getting %d random bytes for context %p\n", 213 byte_count, ctx); 218 byte_count, ctx); 214 219 215 220 216 remainder: 221 remainder: 217 if (ctx->rand_data_valid == DEFAULT_BL 222 if (ctx->rand_data_valid == DEFAULT_BLK_SZ) { 218 if (_get_more_prng_bytes(ctx, 223 if (_get_more_prng_bytes(ctx, do_cont_test) < 0) { 219 memset(buf, 0, nbytes) 224 memset(buf, 0, nbytes); 220 err = -EINVAL; 225 err = -EINVAL; 221 goto done; 226 goto done; 222 } 227 } 223 } 228 } 224 229 225 /* 230 /* 226 * Copy any data less than an entire b 231 * Copy any data less than an entire block 227 */ 232 */ 228 if (byte_count < DEFAULT_BLK_SZ) { 233 if (byte_count < DEFAULT_BLK_SZ) { 229 empty_rbuf: 234 empty_rbuf: 230 while (ctx->rand_data_valid < 235 while (ctx->rand_data_valid < DEFAULT_BLK_SZ) { 231 *ptr = ctx->rand_data[ 236 *ptr = ctx->rand_data[ctx->rand_data_valid]; 232 ptr++; 237 ptr++; 233 byte_count--; 238 byte_count--; 234 ctx->rand_data_valid++ 239 ctx->rand_data_valid++; 235 if (byte_count == 0) 240 if (byte_count == 0) 236 goto done; 241 goto done; 237 } 242 } 238 } 243 } 239 244 240 /* 245 /* 241 * Now copy whole blocks 246 * Now copy whole blocks 242 */ 247 */ 243 for (; byte_count >= DEFAULT_BLK_SZ; b 248 for (; byte_count >= DEFAULT_BLK_SZ; byte_count -= DEFAULT_BLK_SZ) { 244 if (ctx->rand_data_valid == DE 249 if (ctx->rand_data_valid == DEFAULT_BLK_SZ) { 245 if (_get_more_prng_byt 250 if (_get_more_prng_bytes(ctx, do_cont_test) < 0) { 246 memset(buf, 0, 251 memset(buf, 0, nbytes); 247 err = -EINVAL; 252 err = -EINVAL; 248 goto done; 253 goto done; 249 } 254 } 250 } 255 } 251 if (ctx->rand_data_valid > 0) 256 if (ctx->rand_data_valid > 0) 252 goto empty_rbuf; 257 goto empty_rbuf; 253 memcpy(ptr, ctx->rand_data, DE 258 memcpy(ptr, ctx->rand_data, DEFAULT_BLK_SZ); 254 ctx->rand_data_valid += DEFAUL 259 ctx->rand_data_valid += DEFAULT_BLK_SZ; 255 ptr += DEFAULT_BLK_SZ; 260 ptr += DEFAULT_BLK_SZ; 256 } 261 } 257 262 258 /* 263 /* 259 * Now go back and get any remaining p 264 * Now go back and get any remaining partial block 260 */ 265 */ 261 if (byte_count) 266 if (byte_count) 262 goto remainder; 267 goto remainder; 263 268 264 done: 269 done: 265 spin_unlock_bh(&ctx->prng_lock); 270 spin_unlock_bh(&ctx->prng_lock); 266 dbgprint(KERN_CRIT "returning %d from 271 dbgprint(KERN_CRIT "returning %d from get_prng_bytes in context %p\n", 267 err, ctx); 272 err, ctx); 268 return err; 273 return err; 269 } 274 } 270 275 271 static void free_prng_context(struct prng_cont 276 static void free_prng_context(struct prng_context *ctx) 272 { 277 { 273 crypto_free_cipher(ctx->tfm); 278 crypto_free_cipher(ctx->tfm); 274 } 279 } 275 280 276 static int reset_prng_context(struct prng_cont 281 static int reset_prng_context(struct prng_context *ctx, 277 const unsigned c 282 const unsigned char *key, size_t klen, 278 const unsigned c 283 const unsigned char *V, const unsigned char *DT) 279 { 284 { 280 int ret; 285 int ret; 281 const unsigned char *prng_key; 286 const unsigned char *prng_key; 282 287 283 spin_lock_bh(&ctx->prng_lock); 288 spin_lock_bh(&ctx->prng_lock); 284 ctx->flags |= PRNG_NEED_RESET; 289 ctx->flags |= PRNG_NEED_RESET; 285 290 286 prng_key = (key != NULL) ? key : (unsi 291 prng_key = (key != NULL) ? key : (unsigned char *)DEFAULT_PRNG_KEY; 287 292 288 if (!key) 293 if (!key) 289 klen = DEFAULT_PRNG_KSZ; 294 klen = DEFAULT_PRNG_KSZ; 290 295 291 if (V) 296 if (V) 292 memcpy(ctx->V, V, DEFAULT_BLK_ 297 memcpy(ctx->V, V, DEFAULT_BLK_SZ); 293 else 298 else 294 memcpy(ctx->V, DEFAULT_V_SEED, 299 memcpy(ctx->V, DEFAULT_V_SEED, DEFAULT_BLK_SZ); 295 300 296 if (DT) 301 if (DT) 297 memcpy(ctx->DT, DT, DEFAULT_BL 302 memcpy(ctx->DT, DT, DEFAULT_BLK_SZ); 298 else 303 else 299 memset(ctx->DT, 0, DEFAULT_BLK 304 memset(ctx->DT, 0, DEFAULT_BLK_SZ); 300 305 301 memset(ctx->rand_data, 0, DEFAULT_BLK_ 306 memset(ctx->rand_data, 0, DEFAULT_BLK_SZ); 302 memset(ctx->last_rand_data, 0, DEFAULT 307 memset(ctx->last_rand_data, 0, DEFAULT_BLK_SZ); 303 308 304 ctx->rand_data_valid = DEFAULT_BLK_SZ; 309 ctx->rand_data_valid = DEFAULT_BLK_SZ; 305 310 306 ret = crypto_cipher_setkey(ctx->tfm, p 311 ret = crypto_cipher_setkey(ctx->tfm, prng_key, klen); 307 if (ret) { 312 if (ret) { 308 dbgprint(KERN_CRIT "PRNG: setk 313 dbgprint(KERN_CRIT "PRNG: setkey() failed flags=%x\n", 309 crypto_cipher_get_flag 314 crypto_cipher_get_flags(ctx->tfm)); 310 goto out; 315 goto out; 311 } 316 } 312 317 313 ret = 0; 318 ret = 0; 314 ctx->flags &= ~PRNG_NEED_RESET; 319 ctx->flags &= ~PRNG_NEED_RESET; 315 out: 320 out: 316 spin_unlock_bh(&ctx->prng_lock); 321 spin_unlock_bh(&ctx->prng_lock); 317 return ret; 322 return ret; 318 } 323 } 319 324 320 static int cprng_init(struct crypto_tfm *tfm) 325 static int cprng_init(struct crypto_tfm *tfm) 321 { 326 { 322 struct prng_context *ctx = crypto_tfm_ 327 struct prng_context *ctx = crypto_tfm_ctx(tfm); 323 328 324 spin_lock_init(&ctx->prng_lock); 329 spin_lock_init(&ctx->prng_lock); 325 ctx->tfm = crypto_alloc_cipher("aes", 330 ctx->tfm = crypto_alloc_cipher("aes", 0, 0); 326 if (IS_ERR(ctx->tfm)) { 331 if (IS_ERR(ctx->tfm)) { 327 dbgprint(KERN_CRIT "Failed to 332 dbgprint(KERN_CRIT "Failed to alloc tfm for context %p\n", 328 ctx); 333 ctx); 329 return PTR_ERR(ctx->tfm); 334 return PTR_ERR(ctx->tfm); 330 } 335 } 331 336 332 if (reset_prng_context(ctx, NULL, DEFA 337 if (reset_prng_context(ctx, NULL, DEFAULT_PRNG_KSZ, NULL, NULL) < 0) 333 return -EINVAL; 338 return -EINVAL; 334 339 335 /* 340 /* 336 * after allocation, we should always 341 * after allocation, we should always force the user to reset 337 * so they don't inadvertently use the 342 * so they don't inadvertently use the insecure default values 338 * without specifying them intentially 343 * without specifying them intentially 339 */ 344 */ 340 ctx->flags |= PRNG_NEED_RESET; 345 ctx->flags |= PRNG_NEED_RESET; 341 return 0; 346 return 0; 342 } 347 } 343 348 344 static void cprng_exit(struct crypto_tfm *tfm) 349 static void cprng_exit(struct crypto_tfm *tfm) 345 { 350 { 346 free_prng_context(crypto_tfm_ctx(tfm)) 351 free_prng_context(crypto_tfm_ctx(tfm)); 347 } 352 } 348 353 349 static int cprng_get_random(struct crypto_rng 354 static int cprng_get_random(struct crypto_rng *tfm, 350 const u8 *src, uns 355 const u8 *src, unsigned int slen, 351 u8 *rdata, unsigne 356 u8 *rdata, unsigned int dlen) 352 { 357 { 353 struct prng_context *prng = crypto_rng 358 struct prng_context *prng = crypto_rng_ctx(tfm); 354 359 355 return get_prng_bytes(rdata, dlen, prn 360 return get_prng_bytes(rdata, dlen, prng, 0); 356 } 361 } 357 362 358 /* 363 /* 359 * This is the cprng_registered reset method 364 * This is the cprng_registered reset method the seed value is 360 * interpreted as the tuple { V KEY DT} 365 * interpreted as the tuple { V KEY DT} 361 * V and KEY are required during reset, and D 366 * V and KEY are required during reset, and DT is optional, detected 362 * as being present by testing the length of 367 * as being present by testing the length of the seed 363 */ 368 */ 364 static int cprng_reset(struct crypto_rng *tfm, 369 static int cprng_reset(struct crypto_rng *tfm, 365 const u8 *seed, unsigne 370 const u8 *seed, unsigned int slen) 366 { 371 { 367 struct prng_context *prng = crypto_rng 372 struct prng_context *prng = crypto_rng_ctx(tfm); 368 const u8 *key = seed + DEFAULT_BLK_SZ; 373 const u8 *key = seed + DEFAULT_BLK_SZ; 369 const u8 *dt = NULL; 374 const u8 *dt = NULL; 370 375 371 if (slen < DEFAULT_PRNG_KSZ + DEFAULT_ 376 if (slen < DEFAULT_PRNG_KSZ + DEFAULT_BLK_SZ) 372 return -EINVAL; 377 return -EINVAL; 373 378 374 if (slen >= (2 * DEFAULT_BLK_SZ + DEFA 379 if (slen >= (2 * DEFAULT_BLK_SZ + DEFAULT_PRNG_KSZ)) 375 dt = key + DEFAULT_PRNG_KSZ; 380 dt = key + DEFAULT_PRNG_KSZ; 376 381 377 reset_prng_context(prng, key, DEFAULT_ 382 reset_prng_context(prng, key, DEFAULT_PRNG_KSZ, seed, dt); 378 383 379 if (prng->flags & PRNG_NEED_RESET) 384 if (prng->flags & PRNG_NEED_RESET) 380 return -EINVAL; 385 return -EINVAL; 381 return 0; 386 return 0; 382 } 387 } 383 388 384 #ifdef CONFIG_CRYPTO_FIPS 389 #ifdef CONFIG_CRYPTO_FIPS 385 static int fips_cprng_get_random(struct crypto 390 static int fips_cprng_get_random(struct crypto_rng *tfm, 386 const u8 *src 391 const u8 *src, unsigned int slen, 387 u8 *rdata, un 392 u8 *rdata, unsigned int dlen) 388 { 393 { 389 struct prng_context *prng = crypto_rng 394 struct prng_context *prng = crypto_rng_ctx(tfm); 390 395 391 return get_prng_bytes(rdata, dlen, prn 396 return get_prng_bytes(rdata, dlen, prng, 1); 392 } 397 } 393 398 394 static int fips_cprng_reset(struct crypto_rng 399 static int fips_cprng_reset(struct crypto_rng *tfm, 395 const u8 *seed, un 400 const u8 *seed, unsigned int slen) 396 { 401 { 397 u8 rdata[DEFAULT_BLK_SZ]; 402 u8 rdata[DEFAULT_BLK_SZ]; 398 const u8 *key = seed + DEFAULT_BLK_SZ; 403 const u8 *key = seed + DEFAULT_BLK_SZ; 399 int rc; 404 int rc; 400 405 401 struct prng_context *prng = crypto_rng 406 struct prng_context *prng = crypto_rng_ctx(tfm); 402 407 403 if (slen < DEFAULT_PRNG_KSZ + DEFAULT_ 408 if (slen < DEFAULT_PRNG_KSZ + DEFAULT_BLK_SZ) 404 return -EINVAL; 409 return -EINVAL; 405 410 406 /* fips strictly requires seed != key 411 /* fips strictly requires seed != key */ 407 if (!memcmp(seed, key, DEFAULT_PRNG_KS 412 if (!memcmp(seed, key, DEFAULT_PRNG_KSZ)) 408 return -EINVAL; 413 return -EINVAL; 409 414 410 rc = cprng_reset(tfm, seed, slen); 415 rc = cprng_reset(tfm, seed, slen); 411 416 412 if (!rc) 417 if (!rc) 413 goto out; 418 goto out; 414 419 415 /* this primes our continuity test */ 420 /* this primes our continuity test */ 416 rc = get_prng_bytes(rdata, DEFAULT_BLK 421 rc = get_prng_bytes(rdata, DEFAULT_BLK_SZ, prng, 0); 417 prng->rand_data_valid = DEFAULT_BLK_SZ 422 prng->rand_data_valid = DEFAULT_BLK_SZ; 418 423 419 out: 424 out: 420 return rc; 425 return rc; 421 } 426 } 422 #endif 427 #endif 423 428 424 static struct rng_alg rng_algs[] = { { 429 static struct rng_alg rng_algs[] = { { 425 .generate = cprng_get_ra 430 .generate = cprng_get_random, 426 .seed = cprng_reset, 431 .seed = cprng_reset, 427 .seedsize = DEFAULT_PRNG 432 .seedsize = DEFAULT_PRNG_KSZ + 2 * DEFAULT_BLK_SZ, 428 .base = { 433 .base = { 429 .cra_name = "std 434 .cra_name = "stdrng", 430 .cra_driver_name = "ans 435 .cra_driver_name = "ansi_cprng", 431 .cra_priority = 100, 436 .cra_priority = 100, 432 .cra_ctxsize = size 437 .cra_ctxsize = sizeof(struct prng_context), 433 .cra_module = THIS 438 .cra_module = THIS_MODULE, 434 .cra_init = cprn 439 .cra_init = cprng_init, 435 .cra_exit = cprn 440 .cra_exit = cprng_exit, 436 } 441 } 437 #ifdef CONFIG_CRYPTO_FIPS 442 #ifdef CONFIG_CRYPTO_FIPS 438 }, { 443 }, { 439 .generate = fips_cprng_g 444 .generate = fips_cprng_get_random, 440 .seed = fips_cprng_r 445 .seed = fips_cprng_reset, 441 .seedsize = DEFAULT_PRNG 446 .seedsize = DEFAULT_PRNG_KSZ + 2 * DEFAULT_BLK_SZ, 442 .base = { 447 .base = { 443 .cra_name = "fip 448 .cra_name = "fips(ansi_cprng)", 444 .cra_driver_name = "fip 449 .cra_driver_name = "fips_ansi_cprng", 445 .cra_priority = 300, 450 .cra_priority = 300, 446 .cra_ctxsize = size 451 .cra_ctxsize = sizeof(struct prng_context), 447 .cra_module = THIS 452 .cra_module = THIS_MODULE, 448 .cra_init = cprn 453 .cra_init = cprng_init, 449 .cra_exit = cprn 454 .cra_exit = cprng_exit, 450 } 455 } 451 #endif 456 #endif 452 } }; 457 } }; 453 458 454 /* Module initalization */ 459 /* Module initalization */ 455 static int __init prng_mod_init(void) 460 static int __init prng_mod_init(void) 456 { 461 { 457 return crypto_register_rngs(rng_algs, 462 return crypto_register_rngs(rng_algs, ARRAY_SIZE(rng_algs)); 458 } 463 } 459 464 460 static void __exit prng_mod_fini(void) 465 static void __exit prng_mod_fini(void) 461 { 466 { 462 crypto_unregister_rngs(rng_algs, ARRAY 467 crypto_unregister_rngs(rng_algs, ARRAY_SIZE(rng_algs)); 463 } 468 } 464 469 465 MODULE_LICENSE("GPL"); 470 MODULE_LICENSE("GPL"); 466 MODULE_DESCRIPTION("Software Pseudo Random Num 471 MODULE_DESCRIPTION("Software Pseudo Random Number Generator"); 467 MODULE_AUTHOR("Neil Horman <nhorman@tuxdriver. 472 MODULE_AUTHOR("Neil Horman <nhorman@tuxdriver.com>"); 468 module_param(dbg, int, 0); 473 module_param(dbg, int, 0); 469 MODULE_PARM_DESC(dbg, "Boolean to enable debug 474 MODULE_PARM_DESC(dbg, "Boolean to enable debugging (0/1 == off/on)"); 470 subsys_initcall(prng_mod_init); !! 475 module_init(prng_mod_init); 471 module_exit(prng_mod_fini); 476 module_exit(prng_mod_fini); 472 MODULE_ALIAS_CRYPTO("stdrng"); 477 MODULE_ALIAS_CRYPTO("stdrng"); 473 MODULE_ALIAS_CRYPTO("ansi_cprng"); 478 MODULE_ALIAS_CRYPTO("ansi_cprng"); 474 MODULE_IMPORT_NS(CRYPTO_INTERNAL); << 475 479
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