1 /*- 2 * Copyright (c) 2000 Mark R V Murray 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/queue.h> 31 #include <sys/systm.h> 32 #include <sys/conf.h> 33 #include <sys/fcntl.h> 34 #include <sys/uio.h> 35 #include <sys/kernel.h> 36 #include <sys/malloc.h> 37 #include <sys/module.h> 38 #include <sys/bus.h> 39 #include <sys/random.h> 40 #include <machine/bus.h> 41 #include <machine/resource.h> 42 #include <sys/rman.h> 43 #include <sys/signalvar.h> 44 #include <sys/sysctl.h> 45 #include <crypto/blowfish/blowfish.h> 46 47 #include <dev/randomdev/yarrow.h> 48 49 static d_open_t random_open; 50 static d_read_t random_read; 51 static d_write_t random_write; 52 53 #define CDEV_MAJOR 2 54 #define RANDOM_MINOR 3 55 #define URANDOM_MINOR 4 56 57 static struct cdevsw random_cdevsw = { 58 /* open */ random_open, 59 /* close */ (d_close_t *)nullop, 60 /* read */ random_read, 61 /* write */ random_write, 62 /* ioctl */ noioctl, 63 /* poll */ nopoll, 64 /* mmap */ nommap, 65 /* strategy */ nostrategy, 66 /* name */ "random", 67 /* maj */ CDEV_MAJOR, 68 /* dump */ nodump, 69 /* psize */ nopsize, 70 /* flags */ 0, 71 /* bmaj */ -1 72 }; 73 74 /* For use with make_dev(9)/destroy_dev(9). */ 75 static dev_t random_dev; 76 static dev_t urandom_dev; 77 78 SYSCTL_NODE(_kern, OID_AUTO, random, CTLFLAG_RW, 0, "Random Number Generator"); 79 SYSCTL_NODE(_kern_random, OID_AUTO, yarrow, CTLFLAG_RW, 0, "Yarrow Parameters"); 80 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, gengateinterval, CTLFLAG_RW, 81 &random_state.gengateinterval, 10, "Generator Gate Interval"); 82 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, bins, CTLFLAG_RW, 83 &random_state.bins, 10, "Execution time tuner"); 84 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, fastthresh, CTLFLAG_RW, 85 &random_state.pool[0].thresh, 100, "Fast pool reseed threshhold"); 86 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, slowthresh, CTLFLAG_RW, 87 &random_state.pool[1].thresh, 160, "Slow pool reseed threshhold"); 88 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, slowoverthresh, CTLFLAG_RW, 89 &random_state.slowoverthresh, 2, "Slow pool over-threshhold reseed"); 90 91 static int 92 random_open(dev_t dev, int flags, int fmt, struct proc *p) 93 { 94 if ((flags & FWRITE) && (securelevel > 0 || suser(p))) 95 return EPERM; 96 else 97 return 0; 98 } 99 100 static int 101 random_read(dev_t dev, struct uio *uio, int flag) 102 { 103 u_int c, ret; 104 int error = 0; 105 void *random_buf; 106 107 c = min(uio->uio_resid, PAGE_SIZE); 108 random_buf = (void *)malloc(c, M_TEMP, M_WAITOK); 109 while (uio->uio_resid > 0 && error == 0) { 110 ret = read_random(random_buf, c); 111 error = uiomove(random_buf, ret, uio); 112 } 113 free(random_buf, M_TEMP); 114 return error; 115 } 116 117 static int 118 random_write(dev_t dev, struct uio *uio, int flag) 119 { 120 u_int c; 121 int error = 0; 122 void *random_buf; 123 124 random_buf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK); 125 while (uio->uio_resid > 0) { 126 c = min(uio->uio_resid, PAGE_SIZE); 127 error = uiomove(random_buf, c, uio); 128 if (error) 129 break; 130 write_random(random_buf, c); 131 } 132 free(random_buf, M_TEMP); 133 return error; 134 } 135 136 static int 137 random_modevent(module_t mod, int type, void *data) 138 { 139 switch(type) { 140 case MOD_LOAD: 141 if (bootverbose) 142 printf("random: <entropy source>\n"); 143 random_dev = make_dev(&random_cdevsw, RANDOM_MINOR, UID_ROOT, 144 GID_WHEEL, 0666, "random"); 145 urandom_dev = make_dev(&random_cdevsw, URANDOM_MINOR, UID_ROOT, 146 GID_WHEEL, 0666, "urandom"); 147 random_init(); 148 return 0; 149 150 case MOD_UNLOAD: 151 random_deinit(); 152 destroy_dev(random_dev); 153 destroy_dev(urandom_dev); 154 return 0; 155 156 case MOD_SHUTDOWN: 157 return 0; 158 159 default: 160 return EOPNOTSUPP; 161 } 162 } 163 164 DEV_MODULE(random, random_modevent, NULL); 165