rndtest.c revision 139749
1112125Ssam/* $OpenBSD$ */ 2112125Ssam 3139749Simp/*- 4112125Ssam * Copyright (c) 2002 Jason L. Wright (jason@thought.net) 5112125Ssam * All rights reserved. 6112125Ssam * 7112125Ssam * Redistribution and use in source and binary forms, with or without 8112125Ssam * modification, are permitted provided that the following conditions 9112125Ssam * are met: 10112125Ssam * 1. Redistributions of source code must retain the above copyright 11112125Ssam * notice, this list of conditions and the following disclaimer. 12112125Ssam * 2. Redistributions in binary form must reproduce the above copyright 13112125Ssam * notice, this list of conditions and the following disclaimer in the 14112125Ssam * documentation and/or other materials provided with the distribution. 15112125Ssam * 3. All advertising materials mentioning features or use of this software 16112125Ssam * must display the following acknowledgement: 17112125Ssam * This product includes software developed by Jason L. Wright 18112125Ssam * 4. The name of the author may not be used to endorse or promote products 19112125Ssam * derived from this software without specific prior written permission. 20112125Ssam * 21112125Ssam * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22112125Ssam * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 23112125Ssam * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 24112125Ssam * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 25112125Ssam * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 26112125Ssam * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 27112125Ssam * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28112125Ssam * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 29112125Ssam * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 30112125Ssam * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31112125Ssam * POSSIBILITY OF SUCH DAMAGE. 32112125Ssam */ 33112125Ssam 34119418Sobrien#include <sys/cdefs.h> 35119418Sobrien__FBSDID("$FreeBSD: head/sys/dev/rndtest/rndtest.c 139749 2005-01-06 01:43:34Z imp $"); 36119418Sobrien 37112125Ssam#include <sys/param.h> 38112125Ssam#include <sys/systm.h> 39112125Ssam#include <sys/bus.h> 40112125Ssam#include <sys/callout.h> 41112125Ssam#include <sys/kernel.h> 42112125Ssam#include <sys/malloc.h> 43112125Ssam#include <sys/module.h> 44112125Ssam#include <sys/random.h> 45112125Ssam#include <sys/sysctl.h> 46112125Ssam#include <machine/stdarg.h> 47112125Ssam 48112125Ssam#include <dev/rndtest/rndtest.h> 49112125Ssam 50112125Ssamstatic void rndtest_test(struct rndtest_state *); 51112125Ssamstatic void rndtest_timeout(void *); 52112125Ssam 53112125Ssam/* The tests themselves */ 54112125Ssamstatic int rndtest_monobit(struct rndtest_state *); 55112125Ssamstatic int rndtest_runs(struct rndtest_state *); 56112125Ssamstatic int rndtest_longruns(struct rndtest_state *); 57112125Ssamstatic int rndtest_chi_4(struct rndtest_state *); 58112125Ssam 59112125Ssamstatic int rndtest_runs_check(struct rndtest_state *, int, int *); 60112125Ssamstatic void rndtest_runs_record(struct rndtest_state *, int, int *); 61112125Ssam 62112125Ssamstatic const struct rndtest_testfunc { 63112125Ssam int (*test)(struct rndtest_state *); 64112125Ssam} rndtest_funcs[] = { 65112125Ssam { rndtest_monobit }, 66112125Ssam { rndtest_runs }, 67112125Ssam { rndtest_chi_4 }, 68112125Ssam { rndtest_longruns }, 69112125Ssam}; 70112125Ssam 71112125Ssam#define RNDTEST_NTESTS (sizeof(rndtest_funcs)/sizeof(rndtest_funcs[0])) 72112125Ssam 73112125SsamSYSCTL_NODE(_kern, OID_AUTO, rndtest, CTLFLAG_RD, 0, "RNG test parameters"); 74112125Ssam 75112125Ssamstatic int rndtest_retest = 120; /* interval in seconds */ 76116815SsamSYSCTL_INT(_kern_rndtest, OID_AUTO, retest, CTLFLAG_RW, &rndtest_retest, 77112125Ssam 0, "retest interval (seconds)"); 78112125Ssamstatic struct rndtest_stats rndstats; 79112125SsamSYSCTL_STRUCT(_kern_rndtest, OID_AUTO, stats, CTLFLAG_RD, &rndstats, 80112125Ssam rndtest_stats, "RNG test statistics"); 81112125Ssamstatic int rndtest_verbose = 1; /* report only failures */ 82112125SsamSYSCTL_INT(_kern_rndtest, OID_AUTO, verbose, CTLFLAG_RW, &rndtest_verbose, 83112125Ssam 0, "display results on console"); 84112125Ssam 85112125Ssamstruct rndtest_state * 86112125Ssamrndtest_attach(device_t dev) 87112125Ssam{ 88112125Ssam struct rndtest_state *rsp; 89112125Ssam 90112125Ssam rsp = malloc(sizeof (*rsp), M_DEVBUF, M_NOWAIT); 91112125Ssam if (rsp != NULL) { 92112125Ssam rsp->rs_begin = rsp->rs_buf; 93112125Ssam rsp->rs_end = rsp->rs_buf + sizeof(rsp->rs_buf); 94112125Ssam rsp->rs_current = rsp->rs_begin; 95112125Ssam rsp->rs_discard = 1; 96112125Ssam rsp->rs_collect = 1; 97112125Ssam rsp->rs_parent = dev; 98116815Ssam#if __FreeBSD_version < 500000 99116815Ssam callout_init(&rsp->rs_to); 100116815Ssam#else 101119137Ssam callout_init(&rsp->rs_to, CALLOUT_MPSAFE); 102116815Ssam#endif 103112125Ssam } else 104112125Ssam device_printf(dev, "rndtest_init: no memory for state block\n"); 105112125Ssam return (rsp); 106112125Ssam} 107112125Ssam 108112125Ssamvoid 109112125Ssamrndtest_detach(struct rndtest_state *rsp) 110112125Ssam{ 111112125Ssam callout_stop(&rsp->rs_to); 112112125Ssam free(rsp, M_DEVBUF); 113112125Ssam} 114112125Ssam 115112125Ssamvoid 116112125Ssamrndtest_harvest(struct rndtest_state *rsp, void *buf, u_int len) 117112125Ssam{ 118116815Ssam size_t i; 119112125Ssam /* 120112125Ssam * If enabled, collect data and run tests when we have enough. 121112125Ssam */ 122112125Ssam if (rsp->rs_collect) { 123112125Ssam for (i = 0; i < len; i++) { 124112125Ssam *rsp->rs_current = ((u_char *) buf)[i]; 125112125Ssam if (++rsp->rs_current == rsp->rs_end) { 126112125Ssam rndtest_test(rsp); 127112125Ssam rsp->rs_current = rsp->rs_begin; 128112125Ssam /* 129112125Ssam * If tests passed, turn off collection and 130112125Ssam * schedule another test. Otherwise we keep 131112125Ssam * testing until the data looks ok. 132112125Ssam */ 133112125Ssam if (!rsp->rs_discard && rndtest_retest != 0) { 134112125Ssam rsp->rs_collect = 0; 135112125Ssam callout_reset(&rsp->rs_to, 136112125Ssam hz * rndtest_retest, 137112125Ssam rndtest_timeout, rsp); 138112125Ssam break; 139112125Ssam } 140112125Ssam } 141112125Ssam } 142112125Ssam } 143112125Ssam /* 144112125Ssam * Only stir entropy that passes muster into the pool. 145112125Ssam */ 146112125Ssam if (rsp->rs_discard) 147112125Ssam rndstats.rst_discard += len; 148116815Ssam else { 149116815Ssam#if __FreeBSD_version < 500000 150116815Ssam /* XXX verify buffer is word aligned */ 151116815Ssam u_int32_t *p = buf; 152116815Ssam for (len /= sizeof (u_int32_t); len; len--) 153116815Ssam add_true_randomness(*p++); 154116815Ssam#else 155112125Ssam random_harvest(buf, len, len*NBBY, 0, RANDOM_PURE); 156116815Ssam#endif 157116815Ssam } 158112125Ssam} 159112125Ssam 160112125Ssamstatic void 161112125Ssamrndtest_test(struct rndtest_state *rsp) 162112125Ssam{ 163112125Ssam int i, rv = 0; 164112125Ssam 165112125Ssam rndstats.rst_tests++; 166112125Ssam for (i = 0; i < RNDTEST_NTESTS; i++) 167112125Ssam rv |= (*rndtest_funcs[i].test)(rsp); 168112125Ssam rsp->rs_discard = (rv != 0); 169112125Ssam} 170112125Ssam 171112125Ssamstatic void 172112125Ssamrndtest_report(struct rndtest_state *rsp, int failure, const char *fmt, ...) 173112125Ssam{ 174112125Ssam char buf[80]; 175112125Ssam va_list ap; 176112125Ssam 177112125Ssam if (rndtest_verbose == 0) 178112125Ssam return; 179112125Ssam if (!failure && rndtest_verbose == 1) /* don't report successes */ 180112125Ssam return; 181112125Ssam va_start(ap, fmt); 182112125Ssam vsnprintf(buf, sizeof (buf), fmt, ap); 183112125Ssam va_end(ap); 184112125Ssam device_printf(rsp->rs_parent, "rndtest: %s\n", buf); 185112125Ssam} 186112125Ssam 187112125Ssam#define RNDTEST_MONOBIT_MINONES 9725 188112125Ssam#define RNDTEST_MONOBIT_MAXONES 10275 189112125Ssam 190112125Ssamstatic int 191112125Ssamrndtest_monobit(struct rndtest_state *rsp) 192112125Ssam{ 193112125Ssam int i, ones = 0, j; 194112125Ssam u_int8_t r; 195112125Ssam 196112125Ssam for (i = 0; i < RNDTEST_NBYTES; i++) { 197112125Ssam r = rsp->rs_buf[i]; 198112125Ssam for (j = 0; j < 8; j++, r <<= 1) 199112125Ssam if (r & 0x80) 200112125Ssam ones++; 201112125Ssam } 202112125Ssam if (ones > RNDTEST_MONOBIT_MINONES && 203112125Ssam ones < RNDTEST_MONOBIT_MAXONES) { 204112125Ssam if (rndtest_verbose > 1) 205112125Ssam rndtest_report(rsp, 0, "monobit pass (%d < %d < %d)", 206112125Ssam RNDTEST_MONOBIT_MINONES, ones, 207112125Ssam RNDTEST_MONOBIT_MAXONES); 208112125Ssam return (0); 209112125Ssam } else { 210112125Ssam if (rndtest_verbose) 211112125Ssam rndtest_report(rsp, 1, 212112125Ssam "monobit failed (%d ones)", ones); 213112125Ssam rndstats.rst_monobit++; 214112125Ssam return (-1); 215112125Ssam } 216112125Ssam} 217112125Ssam 218112125Ssam#define RNDTEST_RUNS_NINTERVAL 6 219112125Ssam 220112125Ssamstatic const struct rndtest_runs_tabs { 221112125Ssam u_int16_t min, max; 222112125Ssam} rndtest_runs_tab[] = { 223112125Ssam { 2343, 2657 }, 224112125Ssam { 1135, 1365 }, 225112125Ssam { 542, 708 }, 226112125Ssam { 251, 373 }, 227112125Ssam { 111, 201 }, 228112125Ssam { 111, 201 }, 229112125Ssam}; 230112125Ssam 231112125Ssamstatic int 232112125Ssamrndtest_runs(struct rndtest_state *rsp) 233112125Ssam{ 234112125Ssam int i, j, ones, zeros, rv = 0; 235112125Ssam int onei[RNDTEST_RUNS_NINTERVAL], zeroi[RNDTEST_RUNS_NINTERVAL]; 236112125Ssam u_int8_t c; 237112125Ssam 238112125Ssam bzero(onei, sizeof(onei)); 239112125Ssam bzero(zeroi, sizeof(zeroi)); 240112125Ssam ones = zeros = 0; 241112125Ssam for (i = 0; i < RNDTEST_NBYTES; i++) { 242112125Ssam c = rsp->rs_buf[i]; 243112125Ssam for (j = 0; j < 8; j++, c <<= 1) { 244112125Ssam if (c & 0x80) { 245112125Ssam ones++; 246112125Ssam rndtest_runs_record(rsp, zeros, zeroi); 247112125Ssam zeros = 0; 248112125Ssam } else { 249112125Ssam zeros++; 250112125Ssam rndtest_runs_record(rsp, ones, onei); 251112125Ssam ones = 0; 252112125Ssam } 253112125Ssam } 254112125Ssam } 255112125Ssam rndtest_runs_record(rsp, ones, onei); 256112125Ssam rndtest_runs_record(rsp, zeros, zeroi); 257112125Ssam 258112125Ssam rv |= rndtest_runs_check(rsp, 0, zeroi); 259112125Ssam rv |= rndtest_runs_check(rsp, 1, onei); 260112125Ssam 261112125Ssam if (rv) 262112125Ssam rndstats.rst_runs++; 263112125Ssam 264112125Ssam return (rv); 265112125Ssam} 266112125Ssam 267112125Ssamstatic void 268112125Ssamrndtest_runs_record(struct rndtest_state *rsp, int len, int *intrv) 269112125Ssam{ 270112125Ssam if (len == 0) 271112125Ssam return; 272112125Ssam if (len > RNDTEST_RUNS_NINTERVAL) 273112125Ssam len = RNDTEST_RUNS_NINTERVAL; 274112125Ssam len -= 1; 275112125Ssam intrv[len]++; 276112125Ssam} 277112125Ssam 278112125Ssamstatic int 279112125Ssamrndtest_runs_check(struct rndtest_state *rsp, int val, int *src) 280112125Ssam{ 281112125Ssam int i, rv = 0; 282112125Ssam 283112125Ssam for (i = 0; i < RNDTEST_RUNS_NINTERVAL; i++) { 284112125Ssam if (src[i] < rndtest_runs_tab[i].min || 285112125Ssam src[i] > rndtest_runs_tab[i].max) { 286112125Ssam rndtest_report(rsp, 1, 287112125Ssam "%s interval %d failed (%d, %d-%d)", 288112125Ssam val ? "ones" : "zeros", 289112125Ssam i + 1, src[i], rndtest_runs_tab[i].min, 290112125Ssam rndtest_runs_tab[i].max); 291112125Ssam rv = -1; 292112125Ssam } else { 293112125Ssam rndtest_report(rsp, 0, 294112125Ssam "runs pass %s interval %d (%d < %d < %d)", 295112125Ssam val ? "ones" : "zeros", 296112125Ssam i + 1, rndtest_runs_tab[i].min, src[i], 297112125Ssam rndtest_runs_tab[i].max); 298112125Ssam } 299112125Ssam } 300112125Ssam return (rv); 301112125Ssam} 302112125Ssam 303112125Ssamstatic int 304112125Ssamrndtest_longruns(struct rndtest_state *rsp) 305112125Ssam{ 306112125Ssam int i, j, ones = 0, zeros = 0, maxones = 0, maxzeros = 0; 307112125Ssam u_int8_t c; 308112125Ssam 309112125Ssam for (i = 0; i < RNDTEST_NBYTES; i++) { 310112125Ssam c = rsp->rs_buf[i]; 311112125Ssam for (j = 0; j < 8; j++, c <<= 1) { 312112125Ssam if (c & 0x80) { 313112125Ssam zeros = 0; 314112125Ssam ones++; 315112125Ssam if (ones > maxones) 316112125Ssam maxones = ones; 317112125Ssam } else { 318112125Ssam ones = 0; 319112125Ssam zeros++; 320112125Ssam if (zeros > maxzeros) 321112125Ssam maxzeros = zeros; 322112125Ssam } 323112125Ssam } 324112125Ssam } 325112125Ssam 326112125Ssam if (maxones < 26 && maxzeros < 26) { 327112125Ssam rndtest_report(rsp, 0, "longruns pass (%d ones, %d zeros)", 328112125Ssam maxones, maxzeros); 329112125Ssam return (0); 330112125Ssam } else { 331112125Ssam rndtest_report(rsp, 1, "longruns fail (%d ones, %d zeros)", 332112125Ssam maxones, maxzeros); 333112125Ssam rndstats.rst_longruns++; 334112125Ssam return (-1); 335112125Ssam } 336112125Ssam} 337112125Ssam 338112125Ssam/* 339112125Ssam * chi^2 test over 4 bits: (this is called the poker test in FIPS 140-2, 340112125Ssam * but it is really the chi^2 test over 4 bits (the poker test as described 341112125Ssam * by Knuth vol 2 is something different, and I take him as authoritative 342112125Ssam * on nomenclature over NIST). 343112125Ssam */ 344112125Ssam#define RNDTEST_CHI4_K 16 345112125Ssam#define RNDTEST_CHI4_K_MASK (RNDTEST_CHI4_K - 1) 346112125Ssam 347112125Ssam/* 348112125Ssam * The unnormalized values are used so that we don't have to worry about 349112125Ssam * fractional precision. The "real" value is found by: 350112125Ssam * (V - 1562500) * (16 / 5000) = Vn (where V is the unnormalized value) 351112125Ssam */ 352112125Ssam#define RNDTEST_CHI4_VMIN 1563181 /* 2.1792 */ 353112125Ssam#define RNDTEST_CHI4_VMAX 1576929 /* 46.1728 */ 354112125Ssam 355112125Ssamstatic int 356112125Ssamrndtest_chi_4(struct rndtest_state *rsp) 357112125Ssam{ 358112125Ssam unsigned int freq[RNDTEST_CHI4_K], i, sum; 359112125Ssam 360112125Ssam for (i = 0; i < RNDTEST_CHI4_K; i++) 361112125Ssam freq[i] = 0; 362112125Ssam 363112125Ssam /* Get number of occurances of each 4 bit pattern */ 364112125Ssam for (i = 0; i < RNDTEST_NBYTES; i++) { 365112125Ssam freq[(rsp->rs_buf[i] >> 4) & RNDTEST_CHI4_K_MASK]++; 366112125Ssam freq[(rsp->rs_buf[i] >> 0) & RNDTEST_CHI4_K_MASK]++; 367112125Ssam } 368112125Ssam 369112125Ssam for (i = 0, sum = 0; i < RNDTEST_CHI4_K; i++) 370112125Ssam sum += freq[i] * freq[i]; 371112125Ssam 372112125Ssam if (sum >= 1563181 && sum <= 1576929) { 373112125Ssam rndtest_report(rsp, 0, "chi^2(4): pass (sum %u)", sum); 374112125Ssam return (0); 375112125Ssam } else { 376112125Ssam rndtest_report(rsp, 1, "chi^2(4): failed (sum %u)", sum); 377112125Ssam rndstats.rst_chi++; 378112125Ssam return (-1); 379112125Ssam } 380112125Ssam} 381112125Ssam 382112125Ssamstatic void 383112125Ssamrndtest_timeout(void *xrsp) 384112125Ssam{ 385112125Ssam struct rndtest_state *rsp = xrsp; 386112125Ssam 387112125Ssam rsp->rs_collect = 1; 388112125Ssam} 389112125Ssam 390112125Ssamstatic int 391112125Ssamrndtest_modevent(module_t mod, int type, void *unused) 392112125Ssam{ 393112125Ssam switch (type) { 394112125Ssam case MOD_LOAD: 395112125Ssam return 0; 396112125Ssam case MOD_UNLOAD: 397112125Ssam return 0; 398112125Ssam } 399112125Ssam return EINVAL; 400112125Ssam} 401112125Ssam 402112125Ssamstatic moduledata_t rndtest_mod = { 403112125Ssam "rndtest", 404112125Ssam rndtest_modevent, 405112125Ssam 0 406112125Ssam}; 407112125SsamDECLARE_MODULE(rndtest, rndtest_mod, SI_SUB_DRIVERS, SI_ORDER_ANY); 408112125SsamMODULE_VERSION(rndtest, 1); 409