summaryrefslogtreecommitdiffstats
path: root/sys/i386/isa/random_machdep.c
diff options
context:
space:
mode:
authorobrien <obrien@FreeBSD.org>2000-04-24 17:30:08 +0000
committerobrien <obrien@FreeBSD.org>2000-04-24 17:30:08 +0000
commita8c8e00c91ee3b7567d3dd2ad6c6394f041928cb (patch)
tree7ec8e4f2ec6e1369ecd37b47e7b485d868935e25 /sys/i386/isa/random_machdep.c
parentf85fa734fac6ee4d477cc35cbd5f6792ee363275 (diff)
downloadFreeBSD-src-a8c8e00c91ee3b7567d3dd2ad6c6394f041928cb.zip
FreeBSD-src-a8c8e00c91ee3b7567d3dd2ad6c6394f041928cb.tar.gz
* Use sys/sys/random.h rather than a i386 specific one.
* There was nothing that should be machine dependant about i386/isa/random_machdep.c, so it is now sys/kern/kern_random.c.
Diffstat (limited to 'sys/i386/isa/random_machdep.c')
-rw-r--r--sys/i386/isa/random_machdep.c379
1 files changed, 0 insertions, 379 deletions
diff --git a/sys/i386/isa/random_machdep.c b/sys/i386/isa/random_machdep.c
deleted file mode 100644
index 5309478..0000000
--- a/sys/i386/isa/random_machdep.c
+++ /dev/null
@@ -1,379 +0,0 @@
-/*
- * random_machdep.c -- A strong random number generator
- *
- * $FreeBSD$
- *
- * Version 0.95, last modified 18-Oct-95
- *
- * Copyright Theodore Ts'o, 1994, 1995. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, and the entire permission notice in its entirety,
- * including the disclaimer of warranties.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. The name of the author may not be used to endorse or promote
- * products derived from this software without specific prior
- * written permission.
- *
- * ALTERNATIVELY, this product may be distributed under the terms of
- * the GNU Public License, in which case the provisions of the GPL are
- * required INSTEAD OF the above restrictions. (This clause is
- * necessary due to a potential bad interaction between the GPL and
- * the restrictions contained in a BSD-style copyright.)
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
- * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
- * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
- * OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <sys/param.h>
-#include <sys/systm.h>
-#include <sys/kernel.h>
-#include <sys/select.h>
-#include <sys/poll.h>
-#include <sys/timetc.h>
-#include <sys/md5.h>
-
-#include <machine/random.h>
-
-#include <i386/isa/icu.h>
-
-#define MAX_BLKDEV 4
-
-/*
- * The pool is stirred with a primitive polynomial of degree 128
- * over GF(2), namely x^128 + x^99 + x^59 + x^31 + x^9 + x^7 + 1.
- * For a pool of size 64, try x^64+x^62+x^38+x^10+x^6+x+1.
- */
-#define POOLWORDS 128 /* Power of 2 - note that this is 32-bit words */
-#define POOLBITS (POOLWORDS*32)
-
-#if POOLWORDS == 128
-#define TAP1 99 /* The polynomial taps */
-#define TAP2 59
-#define TAP3 31
-#define TAP4 9
-#define TAP5 7
-#elif POOLWORDS == 64
-#define TAP1 62 /* The polynomial taps */
-#define TAP2 38
-#define TAP3 10
-#define TAP4 6
-#define TAP5 1
-#else
-#error No primitive polynomial available for chosen POOLWORDS
-#endif
-
-#define WRITEBUFFER 512 /* size in bytes */
-
-/* There is actually only one of these, globally. */
-struct random_bucket {
- u_int add_ptr;
- u_int entropy_count;
- int input_rotate;
- u_int32_t *pool;
- struct selinfo rsel;
-};
-
-/* There is one of these per entropy source */
-struct timer_rand_state {
- u_long last_time;
- int last_delta;
- int nbits;
-};
-
-static struct random_bucket random_state;
-static u_int32_t random_pool[POOLWORDS];
-static struct timer_rand_state keyboard_timer_state;
-static struct timer_rand_state extract_timer_state;
-static struct timer_rand_state irq_timer_state[ICU_LEN];
-#ifdef notyet
-static struct timer_rand_state blkdev_timer_state[MAX_BLKDEV];
-#endif
-static struct wait_queue *random_wait;
-
-#ifndef MIN
-#define MIN(a,b) (((a) < (b)) ? (a) : (b))
-#endif
-
-void
-rand_initialize(void)
-{
- random_state.add_ptr = 0;
- random_state.entropy_count = 0;
- random_state.pool = random_pool;
- random_wait = NULL;
- random_state.rsel.si_flags = 0;
- random_state.rsel.si_pid = 0;
-}
-
-/*
- * This function adds an int into the entropy "pool". It does not
- * update the entropy estimate. The caller must do this if appropriate.
- *
- * The pool is stirred with a primitive polynomial of degree 128
- * over GF(2), namely x^128 + x^99 + x^59 + x^31 + x^9 + x^7 + 1.
- * For a pool of size 64, try x^64+x^62+x^38+x^10+x^6+x+1.
- *
- * We rotate the input word by a changing number of bits, to help
- * assure that all bits in the entropy get toggled. Otherwise, if we
- * consistently feed the entropy pool small numbers (like ticks and
- * scancodes, for example), the upper bits of the entropy pool don't
- * get affected. --- TYT, 10/11/95
- */
-static __inline void
-add_entropy_word(struct random_bucket *r, const u_int32_t input)
-{
- u_int i;
- u_int32_t w;
-
- w = (input << r->input_rotate) | (input >> (32 - r->input_rotate));
- i = r->add_ptr = (r->add_ptr - 1) & (POOLWORDS-1);
- if (i)
- r->input_rotate = (r->input_rotate + 7) & 31;
- else
- /*
- * At the beginning of the pool, add an extra 7 bits
- * rotation, so that successive passes spread the
- * input bits across the pool evenly.
- */
- r->input_rotate = (r->input_rotate + 14) & 31;
-
- /* XOR in the various taps */
- w ^= r->pool[(i+TAP1)&(POOLWORDS-1)];
- w ^= r->pool[(i+TAP2)&(POOLWORDS-1)];
- w ^= r->pool[(i+TAP3)&(POOLWORDS-1)];
- w ^= r->pool[(i+TAP4)&(POOLWORDS-1)];
- w ^= r->pool[(i+TAP5)&(POOLWORDS-1)];
- w ^= r->pool[i];
- /* Rotate w left 1 bit (stolen from SHA) and store */
- r->pool[i] = (w << 1) | (w >> 31);
-}
-
-/*
- * This function adds entropy to the entropy "pool" by using timing
- * delays. It uses the timer_rand_state structure to make an estimate
- * of how any bits of entropy this call has added to the pool.
- *
- * The number "num" is also added to the pool - it should somehow describe
- * the type of event which just happened. This is currently 0-255 for
- * keyboard scan codes, and 256 upwards for interrupts.
- * On the i386, this is assumed to be at most 16 bits, and the high bits
- * are used for a high-resolution timer.
- */
-static void
-add_timer_randomness(struct random_bucket *r, struct timer_rand_state *state,
- u_int num)
-{
- int delta, delta2;
- u_int nbits;
- u_int32_t time;
-
- num ^= timecounter->tc_get_timecount(timecounter) << 16;
- r->entropy_count += 2;
-
- time = ticks;
-
- add_entropy_word(r, (u_int32_t) num);
- add_entropy_word(r, time);
-
- /*
- * Calculate number of bits of randomness we probably
- * added. We take into account the first and second order
- * deltas in order to make our estimate.
- */
- delta = time - state->last_time;
- state->last_time = time;
-
- delta2 = delta - state->last_delta;
- state->last_delta = delta;
-
- if (delta < 0) delta = -delta;
- if (delta2 < 0) delta2 = -delta2;
- delta = MIN(delta, delta2) >> 1;
- for (nbits = 0; delta; nbits++)
- delta >>= 1;
-
- r->entropy_count += nbits;
-
- /* Prevent overflow */
- if (r->entropy_count > POOLBITS)
- r->entropy_count = POOLBITS;
-
- if (r->entropy_count >= 8)
- selwakeup(&random_state.rsel);
-}
-
-void
-add_keyboard_randomness(u_char scancode)
-{
- add_timer_randomness(&random_state, &keyboard_timer_state, scancode);
-}
-
-void
-add_interrupt_randomness(void *vsc)
-{
- int intr;
- struct random_softc *sc = vsc;
-
- (sc->sc_handler)(sc->sc_arg);
- intr = sc->sc_intr;
- add_timer_randomness(&random_state, &irq_timer_state[intr], intr);
-}
-
-#ifdef notused
-void
-add_blkdev_randomness(int major)
-{
- if (major >= MAX_BLKDEV)
- return;
-
- add_timer_randomness(&random_state, &blkdev_timer_state[major],
- 0x200+major);
-}
-#endif /* notused */
-
-#if POOLWORDS % 16
-#error extract_entropy() assumes that POOLWORDS is a multiple of 16 words.
-#endif
-/*
- * This function extracts randomness from the "entropy pool", and
- * returns it in a buffer. This function computes how many remaining
- * bits of entropy are left in the pool, but it does not restrict the
- * number of bytes that are actually obtained.
- */
-static __inline int
-extract_entropy(struct random_bucket *r, char *buf, int nbytes)
-{
- int ret, i;
- u_int32_t tmp[4];
-
- add_timer_randomness(r, &extract_timer_state, nbytes);
-
- /* Redundant, but just in case... */
- if (r->entropy_count > POOLBITS)
- r->entropy_count = POOLBITS;
- /* Why is this here? Left in from Ted Ts'o. Perhaps to limit time. */
- if (nbytes > 32768)
- nbytes = 32768;
-
- ret = nbytes;
- if (r->entropy_count / 8 >= nbytes)
- r->entropy_count -= nbytes*8;
- else
- r->entropy_count = 0;
-
- while (nbytes) {
- /* Hash the pool to get the output */
- tmp[0] = 0x67452301;
- tmp[1] = 0xefcdab89;
- tmp[2] = 0x98badcfe;
- tmp[3] = 0x10325476;
- for (i = 0; i < POOLWORDS; i += 16)
- MD5Transform(tmp, (char *)(r->pool+i));
- /* Modify pool so next hash will produce different results */
- add_entropy_word(r, tmp[0]);
- add_entropy_word(r, tmp[1]);
- add_entropy_word(r, tmp[2]);
- add_entropy_word(r, tmp[3]);
- /*
- * Run the MD5 Transform one more time, since we want
- * to add at least minimal obscuring of the inputs to
- * add_entropy_word(). --- TYT
- */
- MD5Transform(tmp, (char *)(r->pool));
-
- /* Copy data to destination buffer */
- i = MIN(nbytes, 16);
- bcopy(tmp, buf, i);
- nbytes -= i;
- buf += i;
- }
-
- /* Wipe data from memory */
- bzero(tmp, sizeof(tmp));
-
- return ret;
-}
-
-#ifdef notused /* XXX NOT the exported kernel interface */
-/*
- * This function is the exported kernel interface. It returns some
- * number of good random numbers, suitable for seeding TCP sequence
- * numbers, etc.
- */
-void
-get_random_bytes(void *buf, u_int nbytes)
-{
- extract_entropy(&random_state, (char *) buf, nbytes);
-}
-#endif /* notused */
-
-u_int
-read_random(void *buf, u_int nbytes)
-{
- if ((nbytes * 8) > random_state.entropy_count)
- nbytes = random_state.entropy_count / 8;
-
- return extract_entropy(&random_state, (char *)buf, nbytes);
-}
-
-u_int
-read_random_unlimited(void *buf, u_int nbytes)
-{
- return extract_entropy(&random_state, (char *)buf, nbytes);
-}
-
-#ifdef notused
-u_int
-write_random(const char *buf, u_int nbytes)
-{
- u_int i;
- u_int32_t word, *p;
-
- for (i = nbytes, p = (u_int32_t *)buf;
- i >= sizeof(u_int32_t);
- i-= sizeof(u_int32_t), p++)
- add_entropy_word(&random_state, *p);
- if (i) {
- word = 0;
- bcopy(p, &word, i);
- add_entropy_word(&random_state, word);
- }
- return nbytes;
-}
-#endif /* notused */
-
-int
-random_poll(dev_t dev, int events, struct proc *p)
-{
- int s;
- int revents = 0;
-
- s = splhigh();
- if (events & (POLLIN | POLLRDNORM)) {
- if (random_state.entropy_count >= 8)
- revents |= events & (POLLIN | POLLRDNORM);
- else
- selrecord(p, &random_state.rsel);
- }
- splx(s);
- if (events & (POLLOUT | POLLWRNORM))
- revents |= events & (POLLOUT | POLLWRNORM); /* heh */
-
- return (revents);
-}
-
OpenPOWER on IntegriCloud