1*ab073b32Sdr /* 2*ab073b32Sdr * CDDL HEADER START 3*ab073b32Sdr * 4*ab073b32Sdr * The contents of this file are subject to the terms of the 5*ab073b32Sdr * Common Development and Distribution License (the "License"). 6*ab073b32Sdr * You may not use this file except in compliance with the License. 7*ab073b32Sdr * 8*ab073b32Sdr * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9*ab073b32Sdr * or http://www.opensolaris.org/os/licensing. 10*ab073b32Sdr * See the License for the specific language governing permissions 11*ab073b32Sdr * and limitations under the License. 12*ab073b32Sdr * 13*ab073b32Sdr * When distributing Covered Code, include this CDDL HEADER in each 14*ab073b32Sdr * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15*ab073b32Sdr * If applicable, add the following below this CDDL HEADER, with the 16*ab073b32Sdr * fields enclosed by brackets "[]" replaced with your own identifying 17*ab073b32Sdr * information: Portions Copyright [yyyy] [name of copyright owner] 18*ab073b32Sdr * 19*ab073b32Sdr * CDDL HEADER END 20*ab073b32Sdr */ 21*ab073b32Sdr 22*ab073b32Sdr /* 23*ab073b32Sdr * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24*ab073b32Sdr * Use is subject to license terms. 25*ab073b32Sdr */ 26*ab073b32Sdr 27*ab073b32Sdr /* Copyright (c) 1988 AT&T */ 28*ab073b32Sdr /* All Rights Reserved */ 29*ab073b32Sdr 30*ab073b32Sdr #pragma ident "%Z%%M% %I% %E% SMI" 31*ab073b32Sdr 32*ab073b32Sdr /* 33*ab073b32Sdr * drand48, etc. pseudo-random number generator 34*ab073b32Sdr * This implementation assumes unsigned short integers of at least 35*ab073b32Sdr * 16 bits, long integers of at least 32 bits, and ignores 36*ab073b32Sdr * overflows on adding or multiplying two unsigned integers. 37*ab073b32Sdr * Two's-complement representation is assumed in a few places. 38*ab073b32Sdr * Some extra masking is done if unsigneds are exactly 16 bits 39*ab073b32Sdr * or longs are exactly 32 bits, but so what? 40*ab073b32Sdr * An assembly-language implementation would run significantly faster. 41*ab073b32Sdr */ 42*ab073b32Sdr /* 43*ab073b32Sdr * New assumptions (supercede those stated above) for 64-bit work. 44*ab073b32Sdr * Longs are now 64 bits, and we are bound by standards to return 45*ab073b32Sdr * type long, hovever all internal calculations where long was 46*ab073b32Sdr * previously used (32 bit precision) are now using the int32_t 47*ab073b32Sdr * type (32 bit precision in both ILP32 and LP64 worlds). 48*ab073b32Sdr */ 49*ab073b32Sdr 50*ab073b32Sdr #include <sys/mutex.h> 51*ab073b32Sdr 52*ab073b32Sdr static kmutex_t seed_lock; 53*ab073b32Sdr static int init48done = 0; 54*ab073b32Sdr 55*ab073b32Sdr #define EXPORT0(TYPE, fn, fnu) TYPE fn() { \ 56*ab073b32Sdr TYPE res; \ 57*ab073b32Sdr mutex_enter(&seed_lock); \ 58*ab073b32Sdr res = fnu(); \ 59*ab073b32Sdr mutex_exit(&seed_lock); \ 60*ab073b32Sdr return (res); } 61*ab073b32Sdr #define EXPORT1(TYPE, fn, fnu) TYPE fn(unsigned short xsubi[3]) { \ 62*ab073b32Sdr TYPE res; \ 63*ab073b32Sdr mutex_enter(&seed_lock); \ 64*ab073b32Sdr res = fnu(xsubi); \ 65*ab073b32Sdr mutex_exit(&seed_lock); \ 66*ab073b32Sdr return (res); } 67*ab073b32Sdr 68*ab073b32Sdr #define N 16 69*ab073b32Sdr #define MASK ((unsigned)(1 << (N - 1)) + (1 << (N - 1)) - 1) 70*ab073b32Sdr #define LOW(x) ((unsigned)(x) & MASK) 71*ab073b32Sdr #define HIGH(x) LOW((x) >> N) 72*ab073b32Sdr #define MUL(x, y, z) { int32_t l = (int32_t)(x) * (int32_t)(y); \ 73*ab073b32Sdr (z)[0] = LOW(l); (z)[1] = HIGH(l); } 74*ab073b32Sdr #define CARRY(x, y) ((int32_t)(x) + (int32_t)(y) > MASK) 75*ab073b32Sdr #define ADDEQU(x, y, z) (z = CARRY(x, (y)), x = LOW(x + (y))) 76*ab073b32Sdr #define X0 0x330E 77*ab073b32Sdr #define X1 0xABCD 78*ab073b32Sdr #define X2 0x1234 79*ab073b32Sdr #define A0 0xE66D 80*ab073b32Sdr #define A1 0xDEEC 81*ab073b32Sdr #define A2 0x5 82*ab073b32Sdr #define C 0xB 83*ab073b32Sdr #define SET3(x, x0, x1, x2) ((x)[0] = (x0), (x)[1] = (x1), (x)[2] = (x2)) 84*ab073b32Sdr #define SETLOW(x, y, n) SET3(x, LOW((y)[n]), LOW((y)[(n)+1]), LOW((y)[(n)+2])) 85*ab073b32Sdr #define SEED(x0, x1, x2) (SET3(x, x0, x1, x2), SET3(a, A0, A1, A2), c = C) 86*ab073b32Sdr #define REST(v) for (i = 0; i < 3; i++) { xsubi[i] = x[i]; x[i] = temp[i]; } \ 87*ab073b32Sdr return (v) 88*ab073b32Sdr #define NEST(TYPE, f, F) static TYPE f(unsigned short *xsubi) { \ 89*ab073b32Sdr int i; TYPE v; unsigned temp[3]; \ 90*ab073b32Sdr for (i = 0; i < 3; i++) { temp[i] = x[i]; x[i] = LOW(xsubi[i]); } \ 91*ab073b32Sdr v = F(); REST(v); } 92*ab073b32Sdr 93*ab073b32Sdr /* Way ugly solution to problem names, but it works */ 94*ab073b32Sdr #define x _drand48_x 95*ab073b32Sdr #define a _drand48_a 96*ab073b32Sdr #define c _drand48_c 97*ab073b32Sdr /* End way ugly */ 98*ab073b32Sdr static unsigned x[3] = { X0, X1, X2 }, a[3] = { A0, A1, A2 }, c = C; 99*ab073b32Sdr static unsigned short lastx[3]; 100*ab073b32Sdr static void next(void); 101*ab073b32Sdr 102*ab073b32Sdr static double 103*ab073b32Sdr ipf_r_drand48_u(void) 104*ab073b32Sdr { 105*ab073b32Sdr static double two16m = 1.0 / ((int32_t)1 << N); 106*ab073b32Sdr 107*ab073b32Sdr next(); 108*ab073b32Sdr return (two16m * (two16m * (two16m * x[0] + x[1]) + x[2])); 109*ab073b32Sdr } 110*ab073b32Sdr 111*ab073b32Sdr NEST(double, ipf_r_erand48_u, ipf_r_drand48_u) 112*ab073b32Sdr 113*ab073b32Sdr static long 114*ab073b32Sdr ipf_r_lrand48_u(void) 115*ab073b32Sdr { 116*ab073b32Sdr next(); 117*ab073b32Sdr return ((long)((int32_t)x[2] << (N - 1)) + (x[1] >> 1)); 118*ab073b32Sdr } 119*ab073b32Sdr 120*ab073b32Sdr static void 121*ab073b32Sdr init48(void) 122*ab073b32Sdr { 123*ab073b32Sdr mutex_init(&seed_lock, 0L, MUTEX_DRIVER, 0L); 124*ab073b32Sdr init48done = 1; 125*ab073b32Sdr } 126*ab073b32Sdr 127*ab073b32Sdr static long 128*ab073b32Sdr ipf_r_mrand48_u(void) 129*ab073b32Sdr { 130*ab073b32Sdr next(); 131*ab073b32Sdr return ((long)((int32_t)x[2] << N) + x[1]); 132*ab073b32Sdr } 133*ab073b32Sdr 134*ab073b32Sdr static void 135*ab073b32Sdr next(void) 136*ab073b32Sdr { 137*ab073b32Sdr unsigned p[2], q[2], r[2], carry0, carry1; 138*ab073b32Sdr 139*ab073b32Sdr MUL(a[0], x[0], p); 140*ab073b32Sdr ADDEQU(p[0], c, carry0); 141*ab073b32Sdr ADDEQU(p[1], carry0, carry1); 142*ab073b32Sdr MUL(a[0], x[1], q); 143*ab073b32Sdr ADDEQU(p[1], q[0], carry0); 144*ab073b32Sdr MUL(a[1], x[0], r); 145*ab073b32Sdr x[2] = LOW(carry0 + carry1 + CARRY(p[1], r[0]) + q[1] + r[1] + 146*ab073b32Sdr a[0] * x[2] + a[1] * x[1] + a[2] * x[0]); 147*ab073b32Sdr x[1] = LOW(p[1] + r[0]); 148*ab073b32Sdr x[0] = LOW(p[0]); 149*ab073b32Sdr } 150*ab073b32Sdr 151*ab073b32Sdr void 152*ab073b32Sdr ipf_r_srand48(long seedval) 153*ab073b32Sdr { 154*ab073b32Sdr int32_t fixseed = (int32_t)seedval; /* limit to 32 bits */ 155*ab073b32Sdr 156*ab073b32Sdr if (init48done == 0) 157*ab073b32Sdr init48(); 158*ab073b32Sdr mutex_enter(&seed_lock); 159*ab073b32Sdr SEED(X0, LOW(fixseed), HIGH(fixseed)); 160*ab073b32Sdr mutex_exit(&seed_lock); 161*ab073b32Sdr } 162*ab073b32Sdr 163*ab073b32Sdr unsigned short * 164*ab073b32Sdr ipf_r_seed48(unsigned short seed16v[3]) 165*ab073b32Sdr { 166*ab073b32Sdr if (init48done == 0) 167*ab073b32Sdr init48(); 168*ab073b32Sdr mutex_enter(&seed_lock); 169*ab073b32Sdr SETLOW(lastx, x, 0); 170*ab073b32Sdr SEED(LOW(seed16v[0]), LOW(seed16v[1]), LOW(seed16v[2])); 171*ab073b32Sdr mutex_exit(&seed_lock); 172*ab073b32Sdr return (lastx); 173*ab073b32Sdr } 174*ab073b32Sdr 175*ab073b32Sdr void 176*ab073b32Sdr ipf_r_lcong48(unsigned short param[7]) 177*ab073b32Sdr { 178*ab073b32Sdr if (init48done == 0) 179*ab073b32Sdr init48(); 180*ab073b32Sdr mutex_enter(&seed_lock); 181*ab073b32Sdr SETLOW(x, param, 0); 182*ab073b32Sdr SETLOW(a, param, 3); 183*ab073b32Sdr c = LOW(param[6]); 184*ab073b32Sdr mutex_exit(&seed_lock); 185*ab073b32Sdr } 186*ab073b32Sdr 187*ab073b32Sdr NEST(long, ipf_r_nrand48_u, ipf_r_lrand48_u) 188*ab073b32Sdr 189*ab073b32Sdr NEST(long, ipf_r_jrand48_u, ipf_r_mrand48_u) 190*ab073b32Sdr 191*ab073b32Sdr EXPORT0(double, ipf_r_drand48, ipf_r_drand48_u) 192*ab073b32Sdr EXPORT1(double, ipf_r_erand48, ipf_r_erand48_u) 193*ab073b32Sdr 194*ab073b32Sdr EXPORT0(long, ipf_r_lrand48, ipf_r_lrand48_u) 195*ab073b32Sdr EXPORT1(long, ipf_r_nrand48, ipf_r_nrand48_u) 196*ab073b32Sdr 197*ab073b32Sdr EXPORT0(long, ipf_r_mrand48, ipf_r_mrand48_u) 198*ab073b32Sdr EXPORT1(long, ipf_r_jrand48, ipf_r_jrand48_u) 199*ab073b32Sdr 200*ab073b32Sdr #ifdef DRIVER 201*ab073b32Sdr /* 202*ab073b32Sdr This should print the sequences of integers in Tables 2 203*ab073b32Sdr and 1 of the TM: 204*ab073b32Sdr 1623, 3442, 1447, 1829, 1305, ... 205*ab073b32Sdr 657EB7255101, D72A0C966378, 5A743C062A23, ... 206*ab073b32Sdr */ 207*ab073b32Sdr #include <stdio.h> 208*ab073b32Sdr 209*ab073b32Sdr main() 210*ab073b32Sdr { 211*ab073b32Sdr int i; 212*ab073b32Sdr 213*ab073b32Sdr for (i = 0; i < 80; i++) { 214*ab073b32Sdr printf("%4d ", (int)(4096 * ipf_r_drand48())); 215*ab073b32Sdr printf("%.4X%.4X%.4X\n", x[2], x[1], x[0]); 216*ab073b32Sdr } 217*ab073b32Sdr } 218*ab073b32Sdr #else 219*ab073b32Sdr 220*ab073b32Sdr #include <sys/random.h> 221*ab073b32Sdr 222*ab073b32Sdr unsigned 223*ab073b32Sdr ipf_random() 224*ab073b32Sdr { 225*ab073b32Sdr static int seeded = 0; 226*ab073b32Sdr 227*ab073b32Sdr if (seeded == 0) { 228*ab073b32Sdr long seed; 229*ab073b32Sdr 230*ab073b32Sdr /* 231*ab073b32Sdr * Keep reseeding until some good randomness comes from the 232*ab073b32Sdr * kernel. One of two things will happen: it will succeed or 233*ab073b32Sdr * it will fail (with poor randomness), thus creating NAT 234*ab073b32Sdr * sessions will be "slow" until enough randomness is gained 235*ab073b32Sdr * to not need to get more. It isn't necessary to initialise 236*ab073b32Sdr * seed as it will just pickup whatever random garbage has 237*ab073b32Sdr * been left on the heap and that's good enough until we 238*ab073b32Sdr * get some good garbage. 239*ab073b32Sdr */ 240*ab073b32Sdr if (random_get_bytes((uint8_t *)&seed, sizeof (seed)) == 0) 241*ab073b32Sdr seeded = 1; 242*ab073b32Sdr ipf_r_srand48(seed); 243*ab073b32Sdr } 244*ab073b32Sdr 245*ab073b32Sdr return (unsigned)ipf_r_lrand48(); 246*ab073b32Sdr } 247*ab073b32Sdr #endif 248