rndtest.c revision 119418
156067Smarkm/* $OpenBSD$ */ 256067Smarkm 356067Smarkm/* 4117728Smarkm * Copyright (c) 2002 Jason L. Wright (jason@thought.net) 5117728Smarkm * All rights reserved. 6117728Smarkm * 7117728Smarkm * Redistribution and use in source and binary forms, with or without 8117728Smarkm * modification, are permitted provided that the following conditions 9117728Smarkm * are met: 10117728Smarkm * 1. Redistributions of source code must retain the above copyright 11117728Smarkm * notice, this list of conditions and the following disclaimer. 12117728Smarkm * 2. Redistributions in binary form must reproduce the above copyright 13117728Smarkm * notice, this list of conditions and the following disclaimer in the 14117728Smarkm * documentation and/or other materials provided with the distribution. 15117728Smarkm * 3. All advertising materials mentioning features or use of this software 1657452Smarkm * must display the following acknowledgement: 1756067Smarkm * This product includes software developed by Jason L. Wright 18117728Smarkm * 4. The name of the author may not be used to endorse or promote products 19117728Smarkm * derived from this software without specific prior written permission. 20117728Smarkm * 21117728Smarkm * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22117728Smarkm * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 23117728Smarkm * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 2472450Sassar * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 2572450Sassar * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 2672450Sassar * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 2772450Sassar * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2872450Sassar * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 2972450Sassar * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 3072450Sassar * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 3172450Sassar * POSSIBILITY OF SUCH DAMAGE. 3272450Sassar */ 3372450Sassar 3478550Sassar#include <sys/cdefs.h> 3572450Sassar__FBSDID("$FreeBSD: head/sys/dev/rndtest/rndtest.c 119418 2003-08-24 17:55:58Z obrien $"); 3672450Sassar 3772450Sassar#include <sys/param.h> 3872450Sassar#include <sys/systm.h> 3972450Sassar#include <sys/bus.h> 4072450Sassar#include <sys/callout.h> 4172450Sassar#include <sys/kernel.h> 4272450Sassar#include <sys/malloc.h> 4372450Sassar#include <sys/module.h> 4472450Sassar#include <sys/random.h> 4572450Sassar#include <sys/sysctl.h> 4672450Sassar#include <machine/stdarg.h> 4772450Sassar 4872450Sassar#include <dev/rndtest/rndtest.h> 4972450Sassar 5072450Sassarstatic void rndtest_test(struct rndtest_state *); 5172450Sassarstatic void rndtest_timeout(void *); 5272450Sassar 5372450Sassar/* The tests themselves */ 5472450Sassarstatic int rndtest_monobit(struct rndtest_state *); 5572450Sassarstatic int rndtest_runs(struct rndtest_state *); 5672450Sassarstatic int rndtest_longruns(struct rndtest_state *); 5772450Sassarstatic int rndtest_chi_4(struct rndtest_state *); 5872450Sassar 5972450Sassarstatic int rndtest_runs_check(struct rndtest_state *, int, int *); 6078550Sassarstatic void rndtest_runs_record(struct rndtest_state *, int, int *); 6172450Sassar 6272450Sassarstatic const struct rndtest_testfunc { 6372450Sassar int (*test)(struct rndtest_state *); 6472450Sassar} rndtest_funcs[] = { 6572450Sassar { rndtest_monobit }, 6672450Sassar { rndtest_runs }, 6772450Sassar { rndtest_chi_4 }, 6872450Sassar { rndtest_longruns }, 6972450Sassar}; 7072450Sassar 7172450Sassar#define RNDTEST_NTESTS (sizeof(rndtest_funcs)/sizeof(rndtest_funcs[0])) 7272450Sassar 7372450SassarSYSCTL_NODE(_kern, OID_AUTO, rndtest, CTLFLAG_RD, 0, "RNG test parameters"); 7472450Sassar 7572450Sassarstatic int rndtest_retest = 120; /* interval in seconds */ 7656067SmarkmSYSCTL_INT(_kern_rndtest, OID_AUTO, retest, CTLFLAG_RW, &rndtest_retest, 77117728Smarkm 0, "retest interval (seconds)"); 7857566Smarkmstatic struct rndtest_stats rndstats; 7956067SmarkmSYSCTL_STRUCT(_kern_rndtest, OID_AUTO, stats, CTLFLAG_RD, &rndstats, 8056067Smarkm rndtest_stats, "RNG test statistics"); 8156067Smarkmstatic int rndtest_verbose = 1; /* report only failures */ 8276574SassarSYSCTL_INT(_kern_rndtest, OID_AUTO, verbose, CTLFLAG_RW, &rndtest_verbose, 8356067Smarkm 0, "display results on console"); 8456067Smarkm 85117728Smarkmstruct rndtest_state * 8656067Smarkmrndtest_attach(device_t dev) 8756067Smarkm{ 8856067Smarkm struct rndtest_state *rsp; 8956067Smarkm 9056067Smarkm rsp = malloc(sizeof (*rsp), M_DEVBUF, M_NOWAIT); 9156067Smarkm if (rsp != NULL) { 9278550Sassar rsp->rs_begin = rsp->rs_buf; 9356067Smarkm rsp->rs_end = rsp->rs_buf + sizeof(rsp->rs_buf); 94117728Smarkm rsp->rs_current = rsp->rs_begin; 9578550Sassar rsp->rs_discard = 1; 9656067Smarkm rsp->rs_collect = 1; 9790534Sru rsp->rs_parent = dev; 9856067Smarkm#if __FreeBSD_version < 500000 9978550Sassar callout_init(&rsp->rs_to); 10078550Sassar#else 10178550Sassar callout_init(&rsp->rs_to, CALLOUT_MPSAFE); 10278550Sassar#endif 10378550Sassar } else 10478550Sassar device_printf(dev, "rndtest_init: no memory for state block\n"); 10578550Sassar return (rsp); 10678550Sassar} 10778550Sassar 10890931Snectarvoid 10978550Sassarrndtest_detach(struct rndtest_state *rsp) 11078550Sassar{ 11178550Sassar callout_stop(&rsp->rs_to); 11278550Sassar free(rsp, M_DEVBUF); 11378550Sassar} 11478550Sassar 115117728Smarkmvoid 11678550Sassarrndtest_harvest(struct rndtest_state *rsp, void *buf, u_int len) 11778550Sassar{ 118113136Simp size_t i; 11956067Smarkm /* 120117728Smarkm * If enabled, collect data and run tests when we have enough. 12156067Smarkm */ 122117728Smarkm if (rsp->rs_collect) { 123117728Smarkm for (i = 0; i < len; i++) { 12456067Smarkm *rsp->rs_current = ((u_char *) buf)[i]; 12586126Sassar if (++rsp->rs_current == rsp->rs_end) { 12686126Sassar rndtest_test(rsp); 12756067Smarkm rsp->rs_current = rsp->rs_begin; 128117728Smarkm /* 12956067Smarkm * If tests passed, turn off collection and 130117728Smarkm * schedule another test. Otherwise we keep 131117728Smarkm * testing until the data looks ok. 13276574Sassar */ 13356067Smarkm if (!rsp->rs_discard && rndtest_retest != 0) { 134117728Smarkm rsp->rs_collect = 0; 13556067Smarkm callout_reset(&rsp->rs_to, 13656067Smarkm hz * rndtest_retest, 13756067Smarkm rndtest_timeout, rsp); 13857566Smarkm break; 13956067Smarkm } 14056067Smarkm } 14186126Sassar } 14286126Sassar } 143 /* 144 * Only stir entropy that passes muster into the pool. 145 */ 146 if (rsp->rs_discard) 147 rndstats.rst_discard += len; 148 else { 149#if __FreeBSD_version < 500000 150 /* XXX verify buffer is word aligned */ 151 u_int32_t *p = buf; 152 for (len /= sizeof (u_int32_t); len; len--) 153 add_true_randomness(*p++); 154#else 155 random_harvest(buf, len, len*NBBY, 0, RANDOM_PURE); 156#endif 157 } 158} 159 160static void 161rndtest_test(struct rndtest_state *rsp) 162{ 163 int i, rv = 0; 164 165 rndstats.rst_tests++; 166 for (i = 0; i < RNDTEST_NTESTS; i++) 167 rv |= (*rndtest_funcs[i].test)(rsp); 168 rsp->rs_discard = (rv != 0); 169} 170 171static void 172rndtest_report(struct rndtest_state *rsp, int failure, const char *fmt, ...) 173{ 174 char buf[80]; 175 va_list ap; 176 177 if (rndtest_verbose == 0) 178 return; 179 if (!failure && rndtest_verbose == 1) /* don't report successes */ 180 return; 181 va_start(ap, fmt); 182 vsnprintf(buf, sizeof (buf), fmt, ap); 183 va_end(ap); 184 device_printf(rsp->rs_parent, "rndtest: %s\n", buf); 185} 186 187#define RNDTEST_MONOBIT_MINONES 9725 188#define RNDTEST_MONOBIT_MAXONES 10275 189 190static int 191rndtest_monobit(struct rndtest_state *rsp) 192{ 193 int i, ones = 0, j; 194 u_int8_t r; 195 196 for (i = 0; i < RNDTEST_NBYTES; i++) { 197 r = rsp->rs_buf[i]; 198 for (j = 0; j < 8; j++, r <<= 1) 199 if (r & 0x80) 200 ones++; 201 } 202 if (ones > RNDTEST_MONOBIT_MINONES && 203 ones < RNDTEST_MONOBIT_MAXONES) { 204 if (rndtest_verbose > 1) 205 rndtest_report(rsp, 0, "monobit pass (%d < %d < %d)", 206 RNDTEST_MONOBIT_MINONES, ones, 207 RNDTEST_MONOBIT_MAXONES); 208 return (0); 209 } else { 210 if (rndtest_verbose) 211 rndtest_report(rsp, 1, 212 "monobit failed (%d ones)", ones); 213 rndstats.rst_monobit++; 214 return (-1); 215 } 216} 217 218#define RNDTEST_RUNS_NINTERVAL 6 219 220static const struct rndtest_runs_tabs { 221 u_int16_t min, max; 222} rndtest_runs_tab[] = { 223 { 2343, 2657 }, 224 { 1135, 1365 }, 225 { 542, 708 }, 226 { 251, 373 }, 227 { 111, 201 }, 228 { 111, 201 }, 229}; 230 231static int 232rndtest_runs(struct rndtest_state *rsp) 233{ 234 int i, j, ones, zeros, rv = 0; 235 int onei[RNDTEST_RUNS_NINTERVAL], zeroi[RNDTEST_RUNS_NINTERVAL]; 236 u_int8_t c; 237 238 bzero(onei, sizeof(onei)); 239 bzero(zeroi, sizeof(zeroi)); 240 ones = zeros = 0; 241 for (i = 0; i < RNDTEST_NBYTES; i++) { 242 c = rsp->rs_buf[i]; 243 for (j = 0; j < 8; j++, c <<= 1) { 244 if (c & 0x80) { 245 ones++; 246 rndtest_runs_record(rsp, zeros, zeroi); 247 zeros = 0; 248 } else { 249 zeros++; 250 rndtest_runs_record(rsp, ones, onei); 251 ones = 0; 252 } 253 } 254 } 255 rndtest_runs_record(rsp, ones, onei); 256 rndtest_runs_record(rsp, zeros, zeroi); 257 258 rv |= rndtest_runs_check(rsp, 0, zeroi); 259 rv |= rndtest_runs_check(rsp, 1, onei); 260 261 if (rv) 262 rndstats.rst_runs++; 263 264 return (rv); 265} 266 267static void 268rndtest_runs_record(struct rndtest_state *rsp, int len, int *intrv) 269{ 270 if (len == 0) 271 return; 272 if (len > RNDTEST_RUNS_NINTERVAL) 273 len = RNDTEST_RUNS_NINTERVAL; 274 len -= 1; 275 intrv[len]++; 276} 277 278static int 279rndtest_runs_check(struct rndtest_state *rsp, int val, int *src) 280{ 281 int i, rv = 0; 282 283 for (i = 0; i < RNDTEST_RUNS_NINTERVAL; i++) { 284 if (src[i] < rndtest_runs_tab[i].min || 285 src[i] > rndtest_runs_tab[i].max) { 286 rndtest_report(rsp, 1, 287 "%s interval %d failed (%d, %d-%d)", 288 val ? "ones" : "zeros", 289 i + 1, src[i], rndtest_runs_tab[i].min, 290 rndtest_runs_tab[i].max); 291 rv = -1; 292 } else { 293 rndtest_report(rsp, 0, 294 "runs pass %s interval %d (%d < %d < %d)", 295 val ? "ones" : "zeros", 296 i + 1, rndtest_runs_tab[i].min, src[i], 297 rndtest_runs_tab[i].max); 298 } 299 } 300 return (rv); 301} 302 303static int 304rndtest_longruns(struct rndtest_state *rsp) 305{ 306 int i, j, ones = 0, zeros = 0, maxones = 0, maxzeros = 0; 307 u_int8_t c; 308 309 for (i = 0; i < RNDTEST_NBYTES; i++) { 310 c = rsp->rs_buf[i]; 311 for (j = 0; j < 8; j++, c <<= 1) { 312 if (c & 0x80) { 313 zeros = 0; 314 ones++; 315 if (ones > maxones) 316 maxones = ones; 317 } else { 318 ones = 0; 319 zeros++; 320 if (zeros > maxzeros) 321 maxzeros = zeros; 322 } 323 } 324 } 325 326 if (maxones < 26 && maxzeros < 26) { 327 rndtest_report(rsp, 0, "longruns pass (%d ones, %d zeros)", 328 maxones, maxzeros); 329 return (0); 330 } else { 331 rndtest_report(rsp, 1, "longruns fail (%d ones, %d zeros)", 332 maxones, maxzeros); 333 rndstats.rst_longruns++; 334 return (-1); 335 } 336} 337 338/* 339 * chi^2 test over 4 bits: (this is called the poker test in FIPS 140-2, 340 * but it is really the chi^2 test over 4 bits (the poker test as described 341 * by Knuth vol 2 is something different, and I take him as authoritative 342 * on nomenclature over NIST). 343 */ 344#define RNDTEST_CHI4_K 16 345#define RNDTEST_CHI4_K_MASK (RNDTEST_CHI4_K - 1) 346 347/* 348 * The unnormalized values are used so that we don't have to worry about 349 * fractional precision. The "real" value is found by: 350 * (V - 1562500) * (16 / 5000) = Vn (where V is the unnormalized value) 351 */ 352#define RNDTEST_CHI4_VMIN 1563181 /* 2.1792 */ 353#define RNDTEST_CHI4_VMAX 1576929 /* 46.1728 */ 354 355static int 356rndtest_chi_4(struct rndtest_state *rsp) 357{ 358 unsigned int freq[RNDTEST_CHI4_K], i, sum; 359 360 for (i = 0; i < RNDTEST_CHI4_K; i++) 361 freq[i] = 0; 362 363 /* Get number of occurances of each 4 bit pattern */ 364 for (i = 0; i < RNDTEST_NBYTES; i++) { 365 freq[(rsp->rs_buf[i] >> 4) & RNDTEST_CHI4_K_MASK]++; 366 freq[(rsp->rs_buf[i] >> 0) & RNDTEST_CHI4_K_MASK]++; 367 } 368 369 for (i = 0, sum = 0; i < RNDTEST_CHI4_K; i++) 370 sum += freq[i] * freq[i]; 371 372 if (sum >= 1563181 && sum <= 1576929) { 373 rndtest_report(rsp, 0, "chi^2(4): pass (sum %u)", sum); 374 return (0); 375 } else { 376 rndtest_report(rsp, 1, "chi^2(4): failed (sum %u)", sum); 377 rndstats.rst_chi++; 378 return (-1); 379 } 380} 381 382static void 383rndtest_timeout(void *xrsp) 384{ 385 struct rndtest_state *rsp = xrsp; 386 387 rsp->rs_collect = 1; 388} 389 390static int 391rndtest_modevent(module_t mod, int type, void *unused) 392{ 393 switch (type) { 394 case MOD_LOAD: 395 return 0; 396 case MOD_UNLOAD: 397 return 0; 398 } 399 return EINVAL; 400} 401 402static moduledata_t rndtest_mod = { 403 "rndtest", 404 rndtest_modevent, 405 0 406}; 407DECLARE_MODULE(rndtest, rndtest_mod, SI_SUB_DRIVERS, SI_ORDER_ANY); 408MODULE_VERSION(rndtest, 1); 409