1 /* $FreeBSD: src/sys/dev/rndtest/rndtest.c,v 1.1.4.1 2003/06/04 17:10:30 sam Exp $ */ 2 /* $DragonFly: src/sys/dev/crypto/rndtest/rndtest.c,v 1.6 2004/05/13 19:44:31 dillon Exp $ */ 3 /* $OpenBSD$ */ 4 5 /* 6 * Copyright (c) 2002 Jason L. Wright (jason@thought.net) 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by Jason L. Wright 20 * 4. The name of the author may not be used to endorse or promote products 21 * derived from this software without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 25 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 26 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 27 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 28 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 29 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 31 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 32 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 * POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/bus.h> 39 #include <sys/callout.h> 40 #include <sys/kernel.h> 41 #include <sys/malloc.h> 42 #include <sys/module.h> 43 #include <sys/random.h> 44 #include <sys/sysctl.h> 45 #include <machine/stdarg.h> 46 47 #include "rndtest.h" 48 49 static void rndtest_test(struct rndtest_state *); 50 static void rndtest_timeout(void *); 51 52 /* The tests themselves */ 53 static int rndtest_monobit(struct rndtest_state *); 54 static int rndtest_runs(struct rndtest_state *); 55 static int rndtest_longruns(struct rndtest_state *); 56 static int rndtest_chi_4(struct rndtest_state *); 57 58 static int rndtest_runs_check(struct rndtest_state *, int, int *); 59 static void rndtest_runs_record(struct rndtest_state *, int, int *); 60 61 static const struct rndtest_testfunc { 62 int (*test)(struct rndtest_state *); 63 } rndtest_funcs[] = { 64 { rndtest_monobit }, 65 { rndtest_runs }, 66 { rndtest_chi_4 }, 67 { rndtest_longruns }, 68 }; 69 70 #define RNDTEST_NTESTS (sizeof(rndtest_funcs)/sizeof(rndtest_funcs[0])) 71 72 SYSCTL_NODE(_kern, OID_AUTO, rndtest, CTLFLAG_RD, 0, "RNG test parameters"); 73 74 static int rndtest_retest = 120; /* interval in seconds */ 75 SYSCTL_INT(_kern_rndtest, OID_AUTO, retest, CTLFLAG_RW, &rndtest_retest, 76 0, "retest interval (seconds)"); 77 static struct rndtest_stats rndstats; 78 SYSCTL_STRUCT(_kern_rndtest, OID_AUTO, stats, CTLFLAG_RD, &rndstats, 79 rndtest_stats, "RNG test statistics"); 80 static int rndtest_verbose = 1; /* report only failures */ 81 SYSCTL_INT(_kern_rndtest, OID_AUTO, verbose, CTLFLAG_RW, &rndtest_verbose, 82 0, "display results on console"); 83 84 struct rndtest_state * 85 rndtest_attach(device_t dev) 86 { 87 struct rndtest_state *rsp; 88 89 rsp = malloc(sizeof (*rsp), M_DEVBUF, M_INTWAIT); 90 rsp->rs_begin = rsp->rs_buf; 91 rsp->rs_end = rsp->rs_buf + sizeof(rsp->rs_buf); 92 rsp->rs_current = rsp->rs_begin; 93 rsp->rs_discard = 1; 94 rsp->rs_collect = 1; 95 rsp->rs_parent = dev; 96 #if defined(__DragonFly__) || __FreeBSD_version < 500000 97 callout_init(&rsp->rs_to); 98 #else 99 /* NB: 1 means the callout runs w/o Giant locked */ 100 callout_init(&rsp->rs_to, 1); 101 #endif 102 return (rsp); 103 } 104 105 void 106 rndtest_detach(struct rndtest_state *rsp) 107 { 108 callout_stop(&rsp->rs_to); 109 free(rsp, M_DEVBUF); 110 } 111 112 void 113 rndtest_harvest(struct rndtest_state *rsp, void *buf, u_int len) 114 { 115 size_t i; 116 /* 117 * If enabled, collect data and run tests when we have enough. 118 */ 119 if (rsp->rs_collect) { 120 for (i = 0; i < len; i++) { 121 *rsp->rs_current = ((u_char *) buf)[i]; 122 if (++rsp->rs_current == rsp->rs_end) { 123 rndtest_test(rsp); 124 rsp->rs_current = rsp->rs_begin; 125 /* 126 * If tests passed, turn off collection and 127 * schedule another test. Otherwise we keep 128 * testing until the data looks ok. 129 */ 130 if (!rsp->rs_discard && rndtest_retest != 0) { 131 rsp->rs_collect = 0; 132 callout_reset(&rsp->rs_to, 133 hz * rndtest_retest, 134 rndtest_timeout, rsp); 135 break; 136 } 137 } 138 } 139 } 140 /* 141 * Only stir entropy that passes muster into the pool. 142 */ 143 if (rsp->rs_discard) 144 rndstats.rst_discard += len; 145 else { 146 #if defined(__DragonFly__) || __FreeBSD_version < 500000 147 /* XXX verify buffer is word aligned */ 148 u_int32_t *p = buf; 149 for (len /= sizeof (u_int32_t); len; len--) 150 add_true_randomness(*p++); 151 #else 152 random_harvest(buf, len, len*NBBY, 0, RANDOM_PURE); 153 #endif 154 } 155 } 156 157 static void 158 rndtest_test(struct rndtest_state *rsp) 159 { 160 int i, rv = 0; 161 162 rndstats.rst_tests++; 163 for (i = 0; i < RNDTEST_NTESTS; i++) 164 rv |= (*rndtest_funcs[i].test)(rsp); 165 rsp->rs_discard = (rv != 0); 166 } 167 168 static void 169 rndtest_report(struct rndtest_state *rsp, int failure, const char *fmt, ...) 170 { 171 char buf[80]; 172 __va_list ap; 173 174 if (rndtest_verbose == 0) 175 return; 176 if (!failure && rndtest_verbose == 1) /* don't report successes */ 177 return; 178 __va_start(ap, fmt); 179 vsnprintf(buf, sizeof (buf), fmt, ap); 180 __va_end(ap); 181 device_printf(rsp->rs_parent, "rndtest: %s\n", buf); 182 } 183 184 #define RNDTEST_MONOBIT_MINONES 9725 185 #define RNDTEST_MONOBIT_MAXONES 10275 186 187 static int 188 rndtest_monobit(struct rndtest_state *rsp) 189 { 190 int i, ones = 0, j; 191 u_int8_t r; 192 193 for (i = 0; i < RNDTEST_NBYTES; i++) { 194 r = rsp->rs_buf[i]; 195 for (j = 0; j < 8; j++, r <<= 1) 196 if (r & 0x80) 197 ones++; 198 } 199 if (ones > RNDTEST_MONOBIT_MINONES && 200 ones < RNDTEST_MONOBIT_MAXONES) { 201 if (rndtest_verbose > 1) 202 rndtest_report(rsp, 0, "monobit pass (%d < %d < %d)", 203 RNDTEST_MONOBIT_MINONES, ones, 204 RNDTEST_MONOBIT_MAXONES); 205 return (0); 206 } else { 207 if (rndtest_verbose) 208 rndtest_report(rsp, 1, 209 "monobit failed (%d ones)", ones); 210 rndstats.rst_monobit++; 211 return (-1); 212 } 213 } 214 215 #define RNDTEST_RUNS_NINTERVAL 6 216 217 static const struct rndtest_runs_tabs { 218 u_int16_t min, max; 219 } rndtest_runs_tab[] = { 220 { 2343, 2657 }, 221 { 1135, 1365 }, 222 { 542, 708 }, 223 { 251, 373 }, 224 { 111, 201 }, 225 { 111, 201 }, 226 }; 227 228 static int 229 rndtest_runs(struct rndtest_state *rsp) 230 { 231 int i, j, ones, zeros, rv = 0; 232 int onei[RNDTEST_RUNS_NINTERVAL], zeroi[RNDTEST_RUNS_NINTERVAL]; 233 u_int8_t c; 234 235 bzero(onei, sizeof(onei)); 236 bzero(zeroi, sizeof(zeroi)); 237 ones = zeros = 0; 238 for (i = 0; i < RNDTEST_NBYTES; i++) { 239 c = rsp->rs_buf[i]; 240 for (j = 0; j < 8; j++, c <<= 1) { 241 if (c & 0x80) { 242 ones++; 243 rndtest_runs_record(rsp, zeros, zeroi); 244 zeros = 0; 245 } else { 246 zeros++; 247 rndtest_runs_record(rsp, ones, onei); 248 ones = 0; 249 } 250 } 251 } 252 rndtest_runs_record(rsp, ones, onei); 253 rndtest_runs_record(rsp, zeros, zeroi); 254 255 rv |= rndtest_runs_check(rsp, 0, zeroi); 256 rv |= rndtest_runs_check(rsp, 1, onei); 257 258 if (rv) 259 rndstats.rst_runs++; 260 261 return (rv); 262 } 263 264 static void 265 rndtest_runs_record(struct rndtest_state *rsp, int len, int *intrv) 266 { 267 if (len == 0) 268 return; 269 if (len > RNDTEST_RUNS_NINTERVAL) 270 len = RNDTEST_RUNS_NINTERVAL; 271 len -= 1; 272 intrv[len]++; 273 } 274 275 static int 276 rndtest_runs_check(struct rndtest_state *rsp, int val, int *src) 277 { 278 int i, rv = 0; 279 280 for (i = 0; i < RNDTEST_RUNS_NINTERVAL; i++) { 281 if (src[i] < rndtest_runs_tab[i].min || 282 src[i] > rndtest_runs_tab[i].max) { 283 rndtest_report(rsp, 1, 284 "%s interval %d failed (%d, %d-%d)", 285 val ? "ones" : "zeros", 286 i + 1, src[i], rndtest_runs_tab[i].min, 287 rndtest_runs_tab[i].max); 288 rv = -1; 289 } else { 290 rndtest_report(rsp, 0, 291 "runs pass %s interval %d (%d < %d < %d)", 292 val ? "ones" : "zeros", 293 i + 1, rndtest_runs_tab[i].min, src[i], 294 rndtest_runs_tab[i].max); 295 } 296 } 297 return (rv); 298 } 299 300 static int 301 rndtest_longruns(struct rndtest_state *rsp) 302 { 303 int i, j, ones = 0, zeros = 0, maxones = 0, maxzeros = 0; 304 u_int8_t c; 305 306 for (i = 0; i < RNDTEST_NBYTES; i++) { 307 c = rsp->rs_buf[i]; 308 for (j = 0; j < 8; j++, c <<= 1) { 309 if (c & 0x80) { 310 zeros = 0; 311 ones++; 312 if (ones > maxones) 313 maxones = ones; 314 } else { 315 ones = 0; 316 zeros++; 317 if (zeros > maxzeros) 318 maxzeros = zeros; 319 } 320 } 321 } 322 323 if (maxones < 26 && maxzeros < 26) { 324 rndtest_report(rsp, 0, "longruns pass (%d ones, %d zeros)", 325 maxones, maxzeros); 326 return (0); 327 } else { 328 rndtest_report(rsp, 1, "longruns fail (%d ones, %d zeros)", 329 maxones, maxzeros); 330 rndstats.rst_longruns++; 331 return (-1); 332 } 333 } 334 335 /* 336 * chi^2 test over 4 bits: (this is called the poker test in FIPS 140-2, 337 * but it is really the chi^2 test over 4 bits (the poker test as described 338 * by Knuth vol 2 is something different, and I take him as authoritative 339 * on nomenclature over NIST). 340 */ 341 #define RNDTEST_CHI4_K 16 342 #define RNDTEST_CHI4_K_MASK (RNDTEST_CHI4_K - 1) 343 344 /* 345 * The unnormalized values are used so that we don't have to worry about 346 * fractional precision. The "real" value is found by: 347 * (V - 1562500) * (16 / 5000) = Vn (where V is the unnormalized value) 348 */ 349 #define RNDTEST_CHI4_VMIN 1563181 /* 2.1792 */ 350 #define RNDTEST_CHI4_VMAX 1576929 /* 46.1728 */ 351 352 static int 353 rndtest_chi_4(struct rndtest_state *rsp) 354 { 355 unsigned int freq[RNDTEST_CHI4_K], i, sum; 356 357 for (i = 0; i < RNDTEST_CHI4_K; i++) 358 freq[i] = 0; 359 360 /* Get number of occurances of each 4 bit pattern */ 361 for (i = 0; i < RNDTEST_NBYTES; i++) { 362 freq[(rsp->rs_buf[i] >> 4) & RNDTEST_CHI4_K_MASK]++; 363 freq[(rsp->rs_buf[i] >> 0) & RNDTEST_CHI4_K_MASK]++; 364 } 365 366 for (i = 0, sum = 0; i < RNDTEST_CHI4_K; i++) 367 sum += freq[i] * freq[i]; 368 369 if (sum >= 1563181 && sum <= 1576929) { 370 rndtest_report(rsp, 0, "chi^2(4): pass (sum %u)", sum); 371 return (0); 372 } else { 373 rndtest_report(rsp, 1, "chi^2(4): failed (sum %u)", sum); 374 rndstats.rst_chi++; 375 return (-1); 376 } 377 } 378 379 static void 380 rndtest_timeout(void *xrsp) 381 { 382 struct rndtest_state *rsp = xrsp; 383 384 rsp->rs_collect = 1; 385 } 386 387 static int 388 rndtest_modevent(module_t mod, int type, void *unused) 389 { 390 switch (type) { 391 case MOD_LOAD: 392 return 0; 393 case MOD_UNLOAD: 394 return 0; 395 } 396 return EINVAL; 397 } 398 399 static moduledata_t rndtest_mod = { 400 "rndtest", 401 rndtest_modevent, 402 0 403 }; 404 DECLARE_MODULE(rndtest, rndtest_mod, SI_SUB_DRIVERS, SI_ORDER_ANY); 405 MODULE_VERSION(rndtest, 1); 406