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-rw-r--r--libc/bionic/arc4random.c308
1 files changed, 0 insertions, 308 deletions
diff --git a/libc/bionic/arc4random.c b/libc/bionic/arc4random.c
deleted file mode 100644
index d70580a..0000000
--- a/libc/bionic/arc4random.c
+++ /dev/null
@@ -1,308 +0,0 @@
-/* $OpenBSD: arc4random.c,v 1.19 2008/06/04 00:50:23 djm Exp $ */
-
-/*
- * Copyright (c) 1996, David Mazieres <dm@uun.org>
- * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
-/*
- * Arc4 random number generator for OpenBSD.
- *
- * This code is derived from section 17.1 of Applied Cryptography,
- * second edition, which describes a stream cipher allegedly
- * compatible with RSA Labs "RC4" cipher (the actual description of
- * which is a trade secret). The same algorithm is used as a stream
- * cipher called "arcfour" in Tatu Ylonen's ssh package.
- *
- * Here the stream cipher has been modified always to include the time
- * when initializing the state. That makes it impossible to
- * regenerate the same random sequence twice, so this can't be used
- * for encryption, but will generate good random numbers.
- *
- * RC4 is a registered trademark of RSA Laboratories.
- */
-
-#include <fcntl.h>
-#include <limits.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/param.h>
-#include <sys/time.h>
-#include "thread_private.h"
-
-/* BIONIC-BEGIN */
-/* this lock should protect the global variables in this file */
-static pthread_mutex_t _arc4_lock = PTHREAD_MUTEX_INITIALIZER;
-#define _ARC4_LOCK() pthread_mutex_lock(&_arc4_lock)
-#define _ARC4_UNLOCK() pthread_mutex_unlock(&_arc4_lock)
-/* BIONIC-END */
-
-#ifdef __GNUC__
-#define inline __inline
-#else /* !__GNUC__ */
-#define inline
-#endif /* !__GNUC__ */
-
-struct arc4_stream {
- u_int8_t i;
- u_int8_t j;
- u_int8_t s[256];
-};
-
-static int rs_initialized;
-static struct arc4_stream rs;
-static pid_t arc4_stir_pid;
-static int arc4_count;
-
-static inline u_int8_t arc4_getbyte(void);
-
-static inline void
-arc4_init(void)
-{
- int n;
-
- for (n = 0; n < 256; n++)
- rs.s[n] = n;
- rs.i = 0;
- rs.j = 0;
-}
-
-static inline void
-arc4_addrandom(u_char *dat, int datlen)
-{
- int n;
- u_int8_t si;
-
- rs.i--;
- for (n = 0; n < 256; n++) {
- rs.i = (rs.i + 1);
- si = rs.s[rs.i];
- rs.j = (rs.j + si + dat[n % datlen]);
- rs.s[rs.i] = rs.s[rs.j];
- rs.s[rs.j] = si;
- }
- rs.j = rs.i;
-}
-
-static void
-arc4_stir(void)
-{
-#if 1 /* BIONIC-BEGIN */
- int i, fd;
- union {
- struct timeval tv;
- u_int rnd[128 / sizeof(u_int)];
- } rdat;
- int n;
-
- if (!rs_initialized) {
- arc4_init();
- rs_initialized = 1;
- }
-
- fd = open("/dev/urandom", O_RDONLY);
- if (fd != -1) {
- read(fd, rdat.rnd, sizeof(rdat.rnd));
- close(fd);
- }
- else
- {
- /* fd < 0 ? Ah, what the heck. We'll just take
- * whatever was on the stack. just add a little more
- * time-based randomness though
- */
- gettimeofday(&rdat.tv, NULL);
- }
-
- arc4_stir_pid = getpid();
- arc4_addrandom((void *) &rdat, sizeof(rdat));
-#else /* BIONIC-END */
- int i, mib[2];
- size_t len;
- u_char rnd[128];
-
- if (!rs_initialized) {
- arc4_init();
- rs_initialized = 1;
- }
-
- mib[0] = CTL_KERN;
- mib[1] = KERN_ARND;
-
- len = sizeof(rnd);
- sysctl(mib, 2, rnd, &len, NULL, 0);
-
- arc4_stir_pid = getpid();
- arc4_addrandom(rnd, sizeof(rnd));
-#endif
- /*
- * Discard early keystream, as per recommendations in:
- * http://www.wisdom.weizmann.ac.il/~itsik/RC4/Papers/Rc4_ksa.ps
- */
- for (i = 0; i < 256; i++)
- (void)arc4_getbyte();
- arc4_count = 1600000;
-}
-
-static inline u_int8_t
-arc4_getbyte(void)
-{
- u_int8_t si, sj;
-
- rs.i = (rs.i + 1);
- si = rs.s[rs.i];
- rs.j = (rs.j + si);
- sj = rs.s[rs.j];
- rs.s[rs.i] = sj;
- rs.s[rs.j] = si;
- return (rs.s[(si + sj) & 0xff]);
-}
-
-u_int8_t
-__arc4_getbyte(void)
-{
- u_int8_t val;
-
- _ARC4_LOCK();
- if (--arc4_count == 0 || !rs_initialized)
- arc4_stir();
- val = arc4_getbyte();
- _ARC4_UNLOCK();
- return val;
-}
-
-static inline u_int32_t
-arc4_getword(void)
-{
- u_int32_t val;
- val = arc4_getbyte() << 24;
- val |= arc4_getbyte() << 16;
- val |= arc4_getbyte() << 8;
- val |= arc4_getbyte();
- return val;
-}
-
-void
-arc4random_stir(void)
-{
- _ARC4_LOCK();
- arc4_stir();
- _ARC4_UNLOCK();
-}
-
-void
-arc4random_addrandom(u_char *dat, int datlen)
-{
- _ARC4_LOCK();
- if (!rs_initialized)
- arc4_stir();
- arc4_addrandom(dat, datlen);
- _ARC4_UNLOCK();
-}
-
-u_int32_t
-arc4random(void)
-{
- u_int32_t val;
- _ARC4_LOCK();
- arc4_count -= 4;
- if (arc4_count <= 0 || !rs_initialized || arc4_stir_pid != getpid())
- arc4_stir();
- val = arc4_getword();
- _ARC4_UNLOCK();
- return val;
-}
-
-void
-arc4random_buf(void *_buf, size_t n)
-{
- u_char *buf = (u_char *)_buf;
- _ARC4_LOCK();
- if (!rs_initialized || arc4_stir_pid != getpid())
- arc4_stir();
- while (n--) {
- if (--arc4_count <= 0)
- arc4_stir();
- buf[n] = arc4_getbyte();
- }
- _ARC4_UNLOCK();
-}
-
-/*
- * Calculate a uniformly distributed random number less than upper_bound
- * avoiding "modulo bias".
- *
- * Uniformity is achieved by generating new random numbers until the one
- * returned is outside the range [0, 2**32 % upper_bound). This
- * guarantees the selected random number will be inside
- * [2**32 % upper_bound, 2**32) which maps back to [0, upper_bound)
- * after reduction modulo upper_bound.
- */
-u_int32_t
-arc4random_uniform(u_int32_t upper_bound)
-{
- u_int32_t r, min;
-
- if (upper_bound < 2)
- return 0;
-
-#if (ULONG_MAX > 0xffffffffUL)
- min = 0x100000000UL % upper_bound;
-#else
- /* Calculate (2**32 % upper_bound) avoiding 64-bit math */
- if (upper_bound > 0x80000000)
- min = 1 + ~upper_bound; /* 2**32 - upper_bound */
- else {
- /* (2**32 - (x * 2)) % x == 2**32 % x when x <= 2**31 */
- min = ((0xffffffff - (upper_bound * 2)) + 1) % upper_bound;
- }
-#endif
-
- /*
- * This could theoretically loop forever but each retry has
- * p > 0.5 (worst case, usually far better) of selecting a
- * number inside the range we need, so it should rarely need
- * to re-roll.
- */
- for (;;) {
- r = arc4random();
- if (r >= min)
- break;
- }
-
- return r % upper_bound;
-}
-
-#if 0
-/*-------- Test code for i386 --------*/
-#include <stdio.h>
-#include <machine/pctr.h>
-int
-main(int argc, char **argv)
-{
- const int iter = 1000000;
- int i;
- pctrval v;
-
- v = rdtsc();
- for (i = 0; i < iter; i++)
- arc4random();
- v = rdtsc() - v;
- v /= iter;
-
- printf("%qd cycles\n", v);
-}
-#endif
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