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/selinfo.h> 41 #include <sys/random.h> 42 #include <sys/sysctl.h> 43 #include <sys/vnode.h> 44 #include <machine/bus.h> 45 #include <machine/resource.h> 46 #include <crypto/blowfish/blowfish.h> 47 48 #include <dev/random/hash.h> 49 #include <dev/random/yarrow.h> 50 51 static d_open_t random_open; 52 static d_close_t random_close; 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 */ random_close, 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 /* To stash the sysctl's until they are removed */ 84 static struct sysctl_oid *random_sysctl[12]; /* magic # is sysctl count */ 85 static int sysctlcount = 0; 86 87 static int 88 random_open(dev_t dev, int flags, int fmt, struct proc *p) 89 { 90 if ((flags & FWRITE) && (securelevel > 0 || suser(p))) 91 return EPERM; 92 else 93 return 0; 94 } 95 96 static int 97 random_close(dev_t dev, int flags, int fmt, struct proc *p) 98 { 99 if ((flags & FWRITE) && !(securelevel > 0 || suser(p))) 100 random_reseed(); 101 return 0; 102 } 103 104 static int 105 random_read(dev_t dev, struct uio *uio, int flag) 106 { 107 u_int c, ret; 108 int error = 0; 109 void *random_buf; 110 111 while (!random_state.seeded) { 112 if (flag & IO_NDELAY) 113 error = EWOULDBLOCK; 114 else 115 error = tsleep(&random_state, PUSER|PCATCH, "rndblk", 0); 116 if (error != 0) 117 return error; 118 } 119 c = min(uio->uio_resid, PAGE_SIZE); 120 random_buf = (void *)malloc(c, M_TEMP, M_WAITOK); 121 while (uio->uio_resid > 0 && error == 0) { 122 ret = read_random_real(random_buf, c); 123 error = uiomove(random_buf, ret, uio); 124 } 125 free(random_buf, M_TEMP); 126 return error; 127 } 128 129 static int 130 random_write(dev_t dev, struct uio *uio, int flag) 131 { 132 u_int c; 133 int error = 0; 134 void *random_buf; 135 136 random_buf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK); 137 while (uio->uio_resid > 0) { 138 c = min(uio->uio_resid, PAGE_SIZE); 139 error = uiomove(random_buf, c, uio); 140 if (error) 141 break; 142 write_random(random_buf, c); 143 } 144 free(random_buf, M_TEMP); 145 return error; 146 } 147 148 static int 149 random_ioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p) 150 { 151 return ENOTTY; 152 } 153 154 static int 155 random_poll(dev_t dev, int events, struct proc *p) 156 { 157 int revents; 158 159 revents = 0; 160 if (events & (POLLIN | POLLRDNORM)) { 161 if (random_state.seeded) 162 revents = events & (POLLIN | POLLRDNORM); 163 else 164 selrecord(p, &random_state.rsel); 165 } 166 return revents; 167 } 168 169 static int 170 random_modevent(module_t mod, int type, void *data) 171 { 172 struct sysctl_oid *node_base, *node1, *node2; 173 int error, i; 174 175 switch(type) { 176 case MOD_LOAD: 177 error = random_init(); 178 if (error != 0) 179 return error; 180 181 random_sysctl[sysctlcount++] = node_base = 182 SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_kern), 183 OID_AUTO, "random", CTLFLAG_RW, 0, 184 "Random Number Generator"); 185 random_sysctl[sysctlcount++] = node1 = 186 SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(node_base), 187 OID_AUTO, "sys", CTLFLAG_RW, 0, 188 "Entropy Device Parameters"); 189 random_sysctl[sysctlcount++] = 190 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node1), 191 OID_AUTO, "seeded", CTLFLAG_RW, 192 &random_state.seeded, 0, "Seeded State"); 193 random_sysctl[sysctlcount++] = 194 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node1), 195 OID_AUTO, "harvest_ethernet", CTLFLAG_RW, 196 &harvest.ethernet, 0, "Harvest NIC entropy"); 197 random_sysctl[sysctlcount++] = 198 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node1), 199 OID_AUTO, "harvest_point_to_point", CTLFLAG_RW, 200 &harvest.point_to_point, 0, "Harvest serial net entropy"); 201 random_sysctl[sysctlcount++] = 202 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node1), 203 OID_AUTO, "harvest_interrupt", CTLFLAG_RW, 204 &harvest.interrupt, 0, "Harvest IRQ entropy"); 205 random_sysctl[sysctlcount++] = node2 = 206 SYSCTL_ADD_NODE(NULL, SYSCTL_CHILDREN(node_base), 207 OID_AUTO, "yarrow", CTLFLAG_RW, 0, 208 "Yarrow Parameters"); 209 random_sysctl[sysctlcount++] = 210 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node2), 211 OID_AUTO, "gengateinterval", CTLFLAG_RW, 212 &random_state.gengateinterval, 0, 213 "Generator Gate Interval"); 214 random_sysctl[sysctlcount++] = 215 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node2), 216 OID_AUTO, "bins", CTLFLAG_RW, 217 &random_state.bins, 0, 218 "Execution time tuner"); 219 random_sysctl[sysctlcount++] = 220 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node2), 221 OID_AUTO, "fastthresh", CTLFLAG_RW, 222 &random_state.pool[0].thresh, 0, 223 "Fast pool reseed threshhold"); 224 random_sysctl[sysctlcount++] = 225 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node2), 226 OID_AUTO, "slowthresh", CTLFLAG_RW, 227 &random_state.pool[1].thresh, 0, 228 "Slow pool reseed threshhold"); 229 random_sysctl[sysctlcount++] = 230 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(node2), 231 OID_AUTO, "slowoverthresh", CTLFLAG_RW, 232 &random_state.slowoverthresh, 0, 233 "Slow pool over-threshhold reseed"); 234 235 if (bootverbose) 236 printf("random: <entropy source>\n"); 237 random_dev = make_dev(&random_cdevsw, RANDOM_MINOR, UID_ROOT, 238 GID_WHEEL, 0666, "random"); 239 urandom_dev = make_dev(&random_cdevsw, URANDOM_MINOR, UID_ROOT, 240 GID_WHEEL, 0666, "urandom"); /* XXX Temporary */ 241 return 0; 242 243 case MOD_UNLOAD: 244 random_deinit(); 245 destroy_dev(random_dev); 246 destroy_dev(urandom_dev); /* XXX Temporary */ 247 for (i = sysctlcount - 1; i >= 0; i--) 248 if (sysctl_remove_oid(random_sysctl[i], 1, 0) == EINVAL) 249 panic("random: removing sysctl"); 250 return 0; 251 252 case MOD_SHUTDOWN: 253 return 0; 254 255 default: 256 return EOPNOTSUPP; 257 } 258 } 259 260 DEV_MODULE(random, random_modevent, NULL); 261