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/poll.h> 40 #include <sys/proc.h> 41 #include <sys/select.h> 42 #include <sys/random.h> 43 #include <sys/vnode.h> 44 #include <machine/bus.h> 45 #include <machine/resource.h> 46 #include <sys/sysctl.h> 47 #include <crypto/blowfish/blowfish.h> 48 49 #include <dev/random/hash.h> 50 #include <dev/random/yarrow.h> 51 52 static d_open_t random_open; 53 static d_read_t random_read; 54 static d_write_t random_write; 55 static d_ioctl_t random_ioctl; 56 static d_poll_t random_poll; 57 58 #define CDEV_MAJOR 2 59 #define RANDOM_MINOR 3 60 #define URANDOM_MINOR 4 61 62 static struct cdevsw random_cdevsw = { 63 /* open */ random_open, 64 /* close */ (d_close_t *)nullop, 65 /* read */ random_read, 66 /* write */ random_write, 67 /* ioctl */ random_ioctl, 68 /* poll */ random_poll, 69 /* mmap */ nommap, 70 /* strategy */ nostrategy, 71 /* name */ "random", 72 /* maj */ CDEV_MAJOR, 73 /* dump */ nodump, 74 /* psize */ nopsize, 75 /* flags */ 0, 76 /* bmaj */ -1 77 }; 78 79 /* For use with make_dev(9)/destroy_dev(9). */ 80 static dev_t random_dev; 81 static dev_t urandom_dev; /* XXX Temporary */ 82 83 SYSCTL_NODE(_kern, OID_AUTO, random, CTLFLAG_RW, 0, "Random Number Generator"); 84 SYSCTL_NODE(_kern_random, OID_AUTO, yarrow, CTLFLAG_RW, 0, "Yarrow Parameters"); 85 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, gengateinterval, CTLFLAG_RW, 86 &random_state.gengateinterval, 10, "Generator Gate Interval"); 87 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, bins, CTLFLAG_RW, 88 &random_state.bins, 10, "Execution time tuner"); 89 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, fastthresh, CTLFLAG_RW, 90 &random_state.pool[0].thresh, 100, "Fast pool reseed threshhold"); 91 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, slowthresh, CTLFLAG_RW, 92 &random_state.pool[1].thresh, 160, "Slow pool reseed threshhold"); 93 SYSCTL_INT(_kern_random_yarrow, OID_AUTO, slowoverthresh, CTLFLAG_RW, 94 &random_state.slowoverthresh, 2, "Slow pool over-threshhold reseed"); 95 96 static int 97 random_open(dev_t dev, int flags, int fmt, struct proc *p) 98 { 99 if ((flags & FWRITE) && (securelevel > 0 || suser(p))) 100 return EPERM; 101 else 102 return 0; 103 } 104 105 static int 106 random_read(dev_t dev, struct uio *uio, int flag) 107 { 108 u_int c, ret; 109 int error = 0; 110 void *random_buf; 111 112 while (!random_state.seeded) { 113 if (flag & IO_NDELAY) 114 error = EWOULDBLOCK; 115 else 116 error = tsleep(&random_state, PUSER|PCATCH, "rndblk", 0); 117 if (error != 0) 118 return error; 119 } 120 c = min(uio->uio_resid, PAGE_SIZE); 121 random_buf = (void *)malloc(c, M_TEMP, M_WAITOK); 122 while (uio->uio_resid > 0 && error == 0) { 123 ret = read_random_real(random_buf, c); 124 error = uiomove(random_buf, ret, uio); 125 } 126 free(random_buf, M_TEMP); 127 return error; 128 } 129 130 static int 131 random_write(dev_t dev, struct uio *uio, int flag) 132 { 133 u_int c; 134 int error = 0; 135 void *random_buf; 136 137 random_buf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK); 138 while (uio->uio_resid > 0) { 139 c = min(uio->uio_resid, PAGE_SIZE); 140 error = uiomove(random_buf, c, uio); 141 if (error) 142 break; 143 write_random(random_buf, c); 144 } 145 free(random_buf, M_TEMP); 146 return error; 147 } 148 149 static int 150 random_ioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p) 151 { 152 return ENOTTY; 153 } 154 155 static int 156 random_poll(dev_t dev, int events, struct proc *p) 157 { 158 int revents; 159 160 revents = 0; 161 if (events & (POLLIN | POLLRDNORM)) { 162 if (random_state.seeded) 163 revents = events & (POLLIN | POLLRDNORM); 164 else 165 selrecord(p, &random_state.rsel); 166 } 167 return revents; 168 } 169 170 static int 171 random_modevent(module_t mod, int type, void *data) 172 { 173 int error; 174 175 switch(type) { 176 case MOD_LOAD: 177 error = random_init(); 178 if (error != 0) 179 return error; 180 if (bootverbose) 181 printf("random: <entropy source>\n"); 182 random_dev = make_dev(&random_cdevsw, RANDOM_MINOR, UID_ROOT, 183 GID_WHEEL, 0666, "random"); 184 urandom_dev = make_dev(&random_cdevsw, URANDOM_MINOR, UID_ROOT, 185 GID_WHEEL, 0666, "urandom"); /* XXX Temporary */ 186 return 0; 187 188 case MOD_UNLOAD: 189 random_deinit(); 190 destroy_dev(random_dev); 191 destroy_dev(urandom_dev); /* XXX Temporary */ 192 return 0; 193 194 case MOD_SHUTDOWN: 195 return 0; 196 197 default: 198 return EOPNOTSUPP; 199 } 200 } 201 202 DEV_MODULE(random, random_modevent, NULL); 203