 @@ -1,780 +1,782 @@
-/*	$NetBSD: arc4random.c,v 1.30 2015/05/13 23:15:57 justin Exp $	*/
+/*	$NetBSD: arc4random.c,v 1.31 2016/03/25 22:13:23 riastradh Exp $	*/
 /*-
  * Copyright (c) 2014 The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by Taylor R. Campbell.
+ *
  * 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, this list of conditions and the following disclaimer.
  * 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.
+ *
  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  * ``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 FOUNDATION OR CONTRIBUTORS
  * 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.
  */
 /*
  * Legacy arc4random(3) API from OpenBSD reimplemented using the
  * ChaCha20 PRF, with per-thread state.
+ *
  * Security model:
  * - An attacker who sees some outputs cannot predict past or future
  *   outputs.
  * - An attacker who sees the PRNG state cannot predict past outputs.
  * - An attacker who sees a child's PRNG state cannot predict past or
  *   future outputs in the parent, or in other children.
+ *
  * The arc4random(3) API may abort the process if:
+ *
  * (a) the crypto self-test fails,
  * (b) pthread_atfork or thr_keycreate fail, or
  * (c) sysctl(KERN_ARND) fails when reseeding the PRNG.
+ *
  * The crypto self-test, pthread_atfork, and thr_keycreate occur only
  * once, on the first use of any of the arc4random(3) API.  KERN_ARND
  * is unlikely to fail later unless the kernel is seriously broken.
  */
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: arc4random.c,v 1.30 2015/05/13 23:15:57 justin Exp $");
+__RCSID("$NetBSD: arc4random.c,v 1.31 2016/03/25 22:13:23 riastradh Exp $");
 #include "namespace.h"
 #include "reentrant.h"
 #include <sys/bitops.h>
 #include <sys/endian.h>
 #include <sys/errno.h>
 #include <sys/mman.h>
 #include <sys/sysctl.h>
 #include <assert.h>
 #include <sha2.h>
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 #ifdef __weak_alias
 __weak_alias(arc4random,_arc4random)
 __weak_alias(arc4random_addrandom,_arc4random_addrandom)
 __weak_alias(arc4random_buf,_arc4random_buf)
 __weak_alias(arc4random_stir,_arc4random_stir)
 __weak_alias(arc4random_uniform,_arc4random_uniform)
 #endif
 /*
  * For standard ChaCha, use le32dec/le32enc.  We don't need that for
  * the purposes of a nondeterministic random number generator -- we
  * don't need to be bit-for-bit compatible over any wire.
  */
 static inline uint32_t
 crypto_le32dec(const void *p)
+{
 	uint32_t v;
 	(void)memcpy(&v, p, sizeof v);
 	return v;
+}
 static inline void
 crypto_le32enc(void *p, uint32_t v)
+{
 	(void)memcpy(p, &v, sizeof v);
+}
 /* ChaCha core */
 #define	crypto_core_OUTPUTBYTES	64
 #define	crypto_core_INPUTBYTES	16
 #define	crypto_core_KEYBYTES	32
 #define	crypto_core_CONSTBYTES	16
 #define	crypto_core_ROUNDS	20
 static uint32_t
 rotate(uint32_t u, unsigned c)
+{
 	return (u << c) | (u >> (32 - c));
+}
 #define	QUARTERROUND(a, b, c, d) do {					      \
 	(a) += (b); (d) ^= (a); (d) = rotate((d), 16);			      \
 	(c) += (d); (b) ^= (c); (b) = rotate((b), 12);			      \
 	(a) += (b); (d) ^= (a); (d) = rotate((d),  8);			      \
 	(c) += (d); (b) ^= (c); (b) = rotate((b),  7);			      \
 } while (/*CONSTCOND*/0)
 const uint8_t crypto_core_constant32[16] = "expand 32-byte k";
 static void
 crypto_core(uint8_t *out, const uint8_t *in, const uint8_t *k,
     const uint8_t *c)
+{
 	uint32_t x0,x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15;
 	uint32_t j0,j1,j2,j3,j4,j5,j6,j7,j8,j9,j10,j11,j12,j13,j14,j15;
 	int i;
 	j0 = x0 = crypto_le32dec(c + 0);
 	j1 = x1 = crypto_le32dec(c + 4);
 	j2 = x2 = crypto_le32dec(c + 8);
 	j3 = x3 = crypto_le32dec(c + 12);
 	j4 = x4 = crypto_le32dec(k + 0);
 	j5 = x5 = crypto_le32dec(k + 4);
 	j6 = x6 = crypto_le32dec(k + 8);
 	j7 = x7 = crypto_le32dec(k + 12);
 	j8 = x8 = crypto_le32dec(k + 16);
 	j9 = x9 = crypto_le32dec(k + 20);
 	j10 = x10 = crypto_le32dec(k + 24);
 	j11 = x11 = crypto_le32dec(k + 28);
 	j12 = x12 = crypto_le32dec(in + 0);
 	j13 = x13 = crypto_le32dec(in + 4);
 	j14 = x14 = crypto_le32dec(in + 8);
 	j15 = x15 = crypto_le32dec(in + 12);
 	for (i = crypto_core_ROUNDS; i > 0; i -= 2) {
 		QUARTERROUND( x0, x4, x8,x12);
 		QUARTERROUND( x1, x5, x9,x13);
 		QUARTERROUND( x2, x6,x10,x14);
 		QUARTERROUND( x3, x7,x11,x15);
 		QUARTERROUND( x0, x5,x10,x15);
 		QUARTERROUND( x1, x6,x11,x12);
 		QUARTERROUND( x2, x7, x8,x13);
 		QUARTERROUND( x3, x4, x9,x14);
+	}
 	crypto_le32enc(out + 0, x0 + j0);
 	crypto_le32enc(out + 4, x1 + j1);
 	crypto_le32enc(out + 8, x2 + j2);
 	crypto_le32enc(out + 12, x3 + j3);
 	crypto_le32enc(out + 16, x4 + j4);
 	crypto_le32enc(out + 20, x5 + j5);
 	crypto_le32enc(out + 24, x6 + j6);
 	crypto_le32enc(out + 28, x7 + j7);
 	crypto_le32enc(out + 32, x8 + j8);
 	crypto_le32enc(out + 36, x9 + j9);
 	crypto_le32enc(out + 40, x10 + j10);
 	crypto_le32enc(out + 44, x11 + j11);
 	crypto_le32enc(out + 48, x12 + j12);
 	crypto_le32enc(out + 52, x13 + j13);
 	crypto_le32enc(out + 56, x14 + j14);
 	crypto_le32enc(out + 60, x15 + j15);
+}
 /* ChaCha self-test */
 #ifdef _DIAGNOSTIC
 /*
  * Test vector for ChaCha20 from
  * <http://tools.ietf.org/html/draft-strombergson-chacha-test-vectors-00>,
  * test vectors for ChaCha12 and ChaCha8 and for big-endian machines
  * generated by the same crypto_core code with crypto_core_ROUNDS and
  * crypto_le32enc/dec varied.
  */
 static const uint8_t crypto_core_selftest_vector[64] = {
 #if _BYTE_ORDER == _LITTLE_ENDIAN
 #  if crypto_core_ROUNDS == 8
 x3e,0x00,0xef,0x2f,0x89,0x5f,0x40,0xd6,
 x7f,0x5b,0xb8,0xe8,0x1f,0x09,0xa5,0xa1,
 x2c,0x84,0x0e,0xc3,0xce,0x9a,0x7f,0x3b,
 x18,0x1b,0xe1,0x88,0xef,0x71,0x1a,0x1e,
 x98,0x4c,0xe1,0x72,0xb9,0x21,0x6f,0x41,
 x9f,0x44,0x53,0x67,0x45,0x6d,0x56,0x19,
 x31,0x4a,0x42,0xa3,0xda,0x86,0xb0,0x01,
 x38,0x7b,0xfd,0xb8,0x0e,0x0c,0xfe,0x42,
 #  elif crypto_core_ROUNDS == 12
 x9b,0xf4,0x9a,0x6a,0x07,0x55,0xf9,0x53,
 x81,0x1f,0xce,0x12,0x5f,0x26,0x83,0xd5,
 x04,0x29,0xc3,0xbb,0x49,0xe0,0x74,0x14,
 x7e,0x00,0x89,0xa5,0x2e,0xae,0x15,0x5f,
 x05,0x64,0xf8,0x79,0xd2,0x7a,0xe3,0xc0,
 x2c,0xe8,0x28,0x34,0xac,0xfa,0x8c,0x79,
 x3a,0x62,0x9f,0x2c,0xa0,0xde,0x69,0x19,
 x61,0x0b,0xe8,0x2f,0x41,0x13,0x26,0xbe,
 #  elif crypto_core_ROUNDS == 20
 x76,0xb8,0xe0,0xad,0xa0,0xf1,0x3d,0x90,
 x40,0x5d,0x6a,0xe5,0x53,0x86,0xbd,0x28,
 xbd,0xd2,0x19,0xb8,0xa0,0x8d,0xed,0x1a,
 xa8,0x36,0xef,0xcc,0x8b,0x77,0x0d,0xc7,
 xda,0x41,0x59,0x7c,0x51,0x57,0x48,0x8d,
 x77,0x24,0xe0,0x3f,0xb8,0xd8,0x4a,0x37,
 x6a,0x43,0xb8,0xf4,0x15,0x18,0xa1,0x1c,
 xc3,0x87,0xb6,0x69,0xb2,0xee,0x65,0x86,
 #  else
 #    error crypto_core_ROUNDS must be 8, 12, or 20.
 #  endif
 #elif _BYTE_ORDER == _BIG_ENDIAN
 #  if crypto_core_ROUNDS == 8
 x9a,0x13,0x07,0xe3,0x38,0x18,0x9e,0x99,
 x15,0x37,0x16,0x4d,0x04,0xe6,0x48,0x9a,
 x07,0xd6,0xe8,0x7a,0x02,0xf9,0xf5,0xc7,
 x3f,0xa9,0xc2,0x0a,0xe1,0xc6,0x62,0xea,
 x80,0xaf,0xb6,0x51,0xca,0x52,0x43,0x87,
 xe3,0xa6,0xa6,0x61,0x11,0xf5,0xe6,0xcf,
 x09,0x0f,0xdc,0x9d,0xc3,0xc3,0xbb,0x43,
 xd7,0xfa,0x70,0x42,0xbf,0xa5,0xee,0xa2,
 #  elif crypto_core_ROUNDS == 12
 xcf,0x6c,0x16,0x48,0xbf,0xf4,0xba,0x85,
 x32,0x69,0xd3,0x98,0xc8,0x7d,0xcd,0x3f,
 xdc,0x76,0x6b,0xa2,0x7b,0xcb,0x17,0x4d,
 x05,0xda,0xdd,0xd8,0x62,0x54,0xbf,0xe0,
 x65,0xed,0x0e,0xf4,0x01,0x7e,0x3c,0x05,
 x35,0xb2,0x7a,0x60,0xf3,0x8f,0x12,0x33,
 x24,0x60,0xcd,0x85,0xfe,0x4c,0xf3,0x39,
 xb1,0x0e,0x3e,0xe0,0xba,0xa6,0x2f,0xa9,
 #  elif crypto_core_ROUNDS == 20
 x83,0x8b,0xf8,0x75,0xf7,0xde,0x9d,0x8c,
 x33,0x14,0x72,0x28,0xd1,0xbe,0x88,0xe5,
 x94,0xb5,0xed,0xb8,0x56,0xb5,0x9e,0x0c,
 x64,0x6a,0xaf,0xd9,0xa7,0x49,0x10,0x59,
 xba,0x3a,0x82,0xf8,0x4a,0x70,0x9c,0x00,
 x82,0x2c,0xae,0xc6,0xd7,0x1c,0x2e,0xda,
 x2a,0xfb,0x61,0x70,0x2b,0xd1,0xbf,0x8b,
 x95,0xbc,0x23,0xb6,0x4b,0x60,0x02,0xec,
 #  else
 #    error crypto_core_ROUNDS must be 8, 12, or 20.
 #  endif
 #else
 #  error Byte order must be little-endian or big-endian.
 #endif
 };
 static int
 crypto_core_selftest(void)
+{
 	const uint8_t nonce[crypto_core_INPUTBYTES] = {0};
 	const uint8_t key[crypto_core_KEYBYTES] = {0};
 	uint8_t block[64];
 	unsigned i;
 	crypto_core(block, nonce, key, crypto_core_constant32);
 	for (i = 0; i < 64; i++) {
 		if (block[i] != crypto_core_selftest_vector[i])
 			return EIO;
+	}
 	return 0;
+}
 #else  /* !_DIAGNOSTIC */
 static int
 crypto_core_selftest(void)
+{
 	return 0;
+}
 #endif
 /* PRNG */
 /*
  * For a state s, rather than use ChaCha20 as a stream cipher to
  * generate the concatenation ChaCha20_s(0) || ChaCha20_s(1) || ..., we
  * split ChaCha20_s(0) into s' || x and yield x for the first request,
  * split ChaCha20_s'(0) into s'' || y and yield y for the second
  * request, &c.  This provides backtracking resistance: an attacker who
  * finds s'' can't recover s' or x.
  */
 #define	crypto_prng_SEEDBYTES		crypto_core_KEYBYTES
 #define	crypto_prng_MAXOUTPUTBYTES	\
 	(crypto_core_OUTPUTBYTES - crypto_prng_SEEDBYTES)
 struct crypto_prng {
 	uint8_t		state[crypto_prng_SEEDBYTES];
 };
 static void
 crypto_prng_seed(struct crypto_prng *prng, const void *seed)
+{
 	(void)memcpy(prng->state, seed, crypto_prng_SEEDBYTES);
+}
 static void
 crypto_prng_buf(struct crypto_prng *prng, void *buf, size_t n)
+{
 	const uint8_t nonce[crypto_core_INPUTBYTES] = {0};
 	uint8_t output[crypto_core_OUTPUTBYTES];
 	_DIAGASSERT(n <= crypto_prng_MAXOUTPUTBYTES);
 	__CTASSERT(sizeof prng->state + crypto_prng_MAXOUTPUTBYTES
 	    <= sizeof output);
 	crypto_core(output, nonce, prng->state, crypto_core_constant32);
 	(void)memcpy(prng->state, output, sizeof prng->state);
 	(void)memcpy(buf, output + sizeof prng->state, n);
 	(void)explicit_memset(output, 0, sizeof output);
+}
 /* One-time stream: expand short single-use secret into long secret */
 #define	crypto_onetimestream_SEEDBYTES	crypto_core_KEYBYTES
 static void
 crypto_onetimestream(const void *seed, void *buf, size_t n)
+{
 	uint32_t nonce[crypto_core_INPUTBYTES / sizeof(uint32_t)] = {0};
 	uint8_t block[crypto_core_OUTPUTBYTES];
 	uint8_t *p8, *p32;
 	const uint8_t *nonce8 = (const uint8_t *)(void *)nonce;
 	size_t ni, nb, nf;
 	/*
 	 * Guarantee we can generate up to n bytes.  We have
 	 * 2^(8*INPUTBYTES) possible inputs yielding output of
 	 * OUTPUTBYTES*2^(8*INPUTBYTES) bytes.  It suffices to require
 	 * that sizeof n > (1/CHAR_BIT) log_2 n be less than
 	 * (1/CHAR_BIT) log_2 of the total output stream length.  We
 	 * have
+	 *
 	 *	log_2 (o 2^(8 i)) = log_2 o + log_2 2^(8 i)
 	 *	  = log_2 o + 8 i.
 	 */
 	__CTASSERT(CHAR_BIT * sizeof n <=
-	    (/*LINTED*/ilog2(crypto_core_OUTPUTBYTES) + 8 * crypto_core_INPUTBYTES));
+	    (/*LINTED*/ilog2(crypto_core_OUTPUTBYTES) +
 *crypto_core_INPUTBYTES));
 	p8 = buf;
 	p32 = (uint8_t *)roundup2((uintptr_t)p8, 4);
 	ni = p32 - p8;
 	if (n < ni)
 		ni = n;
 	nb = (n - ni) / sizeof block;
 	nf = (n - ni) % sizeof block;
 	_DIAGASSERT(((uintptr_t)p32 & 3) == 0);
 	_DIAGASSERT(ni <= n);
 	_DIAGASSERT(nb <= (n / sizeof block));
 	_DIAGASSERT(nf <= n);
 	_DIAGASSERT(n == (ni + (nb * sizeof block) + nf));
 	_DIAGASSERT(ni < 4);
 	_DIAGASSERT(nf < sizeof block);
 	if (ni) {
 		crypto_core(block, nonce8, seed, crypto_core_constant32);
 		nonce[0]++;
 		(void)memcpy(p8, block, ni);
+	}
 	while (nb--) {
 		crypto_core(p32, nonce8, seed, crypto_core_constant32);
 		if (++nonce[0] == 0)
 			nonce[1]++;
 		p32 += crypto_core_OUTPUTBYTES;
+	}
 	if (nf) {
 		crypto_core(block, nonce8, seed, crypto_core_constant32);
 		if (++nonce[0] == 0)
 			nonce[1]++;
 		(void)memcpy(p32, block, nf);
+	}
 	if (ni | nf)
 		(void)explicit_memset(block, 0, sizeof block);
+}
 /* arc4random state: per-thread, per-process (zeroed in child on fork) */
 struct arc4random_prng {
 	struct crypto_prng	arc4_prng;
 	bool			arc4_seeded;
 };
 static void
 arc4random_prng_addrandom(struct arc4random_prng *prng, const void *data,
     size_t datalen)
+{
 	const int mib[] = { CTL_KERN, KERN_ARND };
 	SHA256_CTX ctx;
 	uint8_t buf[crypto_prng_SEEDBYTES];
 	size_t buflen = sizeof buf;
 	__CTASSERT(sizeof buf == SHA256_DIGEST_LENGTH);
 	SHA256_Init(&ctx);
 	crypto_prng_buf(&prng->arc4_prng, buf, sizeof buf);
 	SHA256_Update(&ctx, buf, sizeof buf);
 	if (sysctl(mib, (u_int)__arraycount(mib), buf, &buflen, NULL, 0) == -1)
 		abort();
 	if (buflen != sizeof buf)
 		abort();
 	SHA256_Update(&ctx, buf, sizeof buf);
 	if (data != NULL)
 		SHA256_Update(&ctx, data, datalen);
 	SHA256_Final(buf, &ctx);
 	(void)explicit_memset(&ctx, 0, sizeof ctx);
 	/* reseed(SHA256(prng() || sysctl(KERN_ARND) || data)) */
 	crypto_prng_seed(&prng->arc4_prng, buf);
 	(void)explicit_memset(buf, 0, sizeof buf);
 	prng->arc4_seeded = true;
+}
 #ifdef _REENTRANT
 static struct arc4random_prng *
 arc4random_prng_create(void)
+{
 	struct arc4random_prng *prng;
 	const size_t size = roundup(sizeof(*prng), sysconf(_SC_PAGESIZE));
-	prng = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
+	prng = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1,
 );
 	if (prng == MAP_FAILED)
 		goto fail0;
 	if (minherit(prng, size, MAP_INHERIT_ZERO) == -1)
 		goto fail1;
 	return prng;
 fail1:	(void)munmap(prng, size);
 fail0:	return NULL;
+}
 #endif
 #ifdef _REENTRANT
 static void
 arc4random_prng_destroy(struct arc4random_prng *prng)
+{
 	const size_t size = roundup(sizeof(*prng), sysconf(_SC_PAGESIZE));
 	(void)explicit_memset(prng, 0, sizeof(*prng));
 	(void)munmap(prng, size);
+}
 #endif
 /* Library state */
 static struct arc4random_global {
 #ifdef _REENTRANT
 	mutex_t			lock;
 	thread_key_t		thread_key;
 #endif
 	struct arc4random_prng	prng;
 	bool			initialized;
 } arc4random_global = {
 #ifdef _REENTRANT
 	.lock		= MUTEX_INITIALIZER,
 #endif
 	.initialized	= false,
 };
 static void
 arc4random_atfork_prepare(void)
+{
 	mutex_lock(&arc4random_global.lock);
 	(void)explicit_memset(&arc4random_global.prng, 0,
 	    sizeof arc4random_global.prng);
+}
 static void
 arc4random_atfork_parent(void)
+{
 	mutex_unlock(&arc4random_global.lock);
+}
 static void
 arc4random_atfork_child(void)
+{
 	mutex_unlock(&arc4random_global.lock);
+}
 #ifdef _REENTRANT
 static void
 arc4random_tsd_destructor(void *p)
+{
 	struct arc4random_prng *const prng = p;
 	arc4random_prng_destroy(prng);
+}
 #endif
 static void
 arc4random_initialize(void)
+{
 	mutex_lock(&arc4random_global.lock);
 	if (!arc4random_global.initialized) {
 		if (crypto_core_selftest() != 0)
 			abort();
 		if (pthread_atfork(&arc4random_atfork_prepare,
 			&arc4random_atfork_parent, &arc4random_atfork_child)
 		    != 0)
 			abort();
 #ifdef _REENTRANT
 		if (thr_keycreate(&arc4random_global.thread_key,
 			&arc4random_tsd_destructor) != 0)
 			abort();
 #endif
 		arc4random_global.initialized = true;
+	}
 	mutex_unlock(&arc4random_global.lock);
+}
 static struct arc4random_prng *
 arc4random_prng_get(void)
+{
 	struct arc4random_prng *prng = NULL;
 	/* Make sure the library is initialized.  */
 	if (__predict_false(!arc4random_global.initialized))
 		arc4random_initialize();
 #ifdef _REENTRANT
 	/* Get or create the per-thread PRNG state.  */
 	prng = thr_getspecific(arc4random_global.thread_key);
 	if (__predict_false(prng == NULL)) {
 		prng = arc4random_prng_create();
 		thr_setspecific(arc4random_global.thread_key, prng);
+	}
 #endif
 	/* If we can't create it, fall back to the global PRNG.  */
 	if (__predict_false(prng == NULL)) {
 		mutex_lock(&arc4random_global.lock);
 		prng = &arc4random_global.prng;
+	}
 	/* Guarantee the PRNG is seeded.  */
 	if (__predict_false(!prng->arc4_seeded))
 		arc4random_prng_addrandom(prng, NULL, 0);
 	return prng;
+}
 static void
 arc4random_prng_put(struct arc4random_prng *prng)
+{
 	/* If we had fallen back to the global PRNG, unlock it.  */
 	if (__predict_false(prng == &arc4random_global.prng))
 		mutex_unlock(&arc4random_global.lock);
+}
 /* Public API */
 uint32_t
 arc4random(void)
+{
 	struct arc4random_prng *prng;
 	uint32_t v;
 	prng = arc4random_prng_get();
 	crypto_prng_buf(&prng->arc4_prng, &v, sizeof v);
 	arc4random_prng_put(prng);
 	return v;
+}
 void
 arc4random_buf(void *buf, size_t len)
+{
 	struct arc4random_prng *prng;
 	if (len <= crypto_prng_MAXOUTPUTBYTES) {
 		prng = arc4random_prng_get();
 		crypto_prng_buf(&prng->arc4_prng, buf, len);
 		arc4random_prng_put(prng);
 	} else {
 		uint8_t seed[crypto_onetimestream_SEEDBYTES];
 		prng = arc4random_prng_get();
 		crypto_prng_buf(&prng->arc4_prng, seed, sizeof seed);
 		arc4random_prng_put(prng);
 		crypto_onetimestream(seed, buf, len);
 		(void)explicit_memset(seed, 0, sizeof seed);
+	}
+}
 uint32_t
 arc4random_uniform(uint32_t bound)
+{
 	struct arc4random_prng *prng;
 	uint32_t minimum, r;
 	/*
 	 * We want a uniform random choice in [0, n), and arc4random()
 	 * makes a uniform random choice in [0, 2^32).  If we reduce
 	 * that modulo n, values in [0, 2^32 mod n) will be represented
 	 * slightly more than values in [2^32 mod n, n).  Instead we
 	 * choose only from [2^32 mod n, 2^32) by rejecting samples in
 	 * [0, 2^32 mod n), to avoid counting the extra representative
 	 * of [0, 2^32 mod n).  To compute 2^32 mod n, note that
+	 *
 	 *	2^32 mod n = 2^32 mod n - 0
 	 *	  = 2^32 mod n - n mod n
 	 *	  = (2^32 - n) mod n,
+	 *
 	 * the last of which is what we compute in 32-bit arithmetic.
 	 */
 	minimum = (-bound % bound);
 	prng = arc4random_prng_get();
 	do crypto_prng_buf(&prng->arc4_prng, &r, sizeof r);
 	while (__predict_false(r < minimum));
 	arc4random_prng_put(prng);
 	return (r % bound);
+}
 void
 arc4random_stir(void)
+{
 	struct arc4random_prng *prng;
 	prng = arc4random_prng_get();
 	arc4random_prng_addrandom(prng, NULL, 0);
 	arc4random_prng_put(prng);
+}
 /*
  * Silly signature here is for hysterical raisins.  Should instead be
  * const void *data and size_t datalen.
  */
 void
 arc4random_addrandom(u_char *data, int datalen)
+{
 	struct arc4random_prng *prng;
 	_DIAGASSERT(0 <= datalen);
 	prng = arc4random_prng_get();
 	arc4random_prng_addrandom(prng, data, datalen);
 	arc4random_prng_put(prng);
+}
 #ifdef _ARC4RANDOM_TEST
 #include <sys/wait.h>
 #include <err.h>
 #include <stdio.h>
 int
 main(int argc __unused, char **argv __unused)
+{
 	unsigned char gubbish[] = "random gubbish";
 	const uint8_t zero64[64] = {0};
 	uint8_t buf[2048];
 	unsigned i, a, n;
 	/* Test arc4random: should not be deterministic.  */
 	if (printf("arc4random: %08"PRIx32"\n", arc4random()) < 0)
 		err(1, "printf");
 	/* Test stirring: should definitely not be deterministic.  */
 	arc4random_stir();
 	/* Test small buffer.  */
 	arc4random_buf(buf, 8);
 	if (printf("arc4randombuf small:") < 0)
 		err(1, "printf");
 	for (i = 0; i < 8; i++)
 		if (printf(" %02x", buf[i]) < 0)
 			err(1, "printf");
 	if (printf("\n") < 0)
 		err(1, "printf");
 	/* Test addrandom: should not make the rest deterministic.  */
 	arc4random_addrandom(gubbish, sizeof gubbish);
 	/* Test large buffer.  */
 	arc4random_buf(buf, sizeof buf);
 	if (printf("arc4randombuf_large:") < 0)
 		err(1, "printf");
 	for (i = 0; i < sizeof buf; i++)
 		if (printf(" %02x", buf[i]) < 0)
 			err(1, "printf");
 	if (printf("\n") < 0)
 		err(1, "printf");
 	/* Test misaligned small and large.  */
 	for (a = 0; a < 64; a++) {
 		for (n = a; n < sizeof buf; n++) {
 			(void)memset(buf, 0, sizeof buf);
 			arc4random_buf(buf, n - a);
 			if (memcmp(buf + n - a, zero64, a) != 0)
 				errx(1, "arc4random buffer overflow 0");
 			(void)memset(buf, 0, sizeof buf);
 			arc4random_buf(buf + a, n - a);
 			if (memcmp(buf, zero64, a) != 0)
 				errx(1, "arc4random buffer overflow 1");
 			if ((2*a) <= n) {
 				(void)memset(buf, 0, sizeof buf);
 				arc4random_buf(buf + a, n - a - a);
 				if (memcmp(buf + n - a, zero64, a) != 0)
 					errx(1,
 					    "arc4random buffer overflow 2");
+			}
+		}
+	}
 	/* Test fork-safety.  */
+    {
 	pid_t pid, rpid;
 	int status;
 	pid = fork();
 	switch (pid) {
 	case -1:
 		err(1, "fork");
 	case 0:
 		_exit(arc4random_prng_get()->arc4_seeded);
 	default:
 		rpid = waitpid(pid, &status, 0);
 		if (rpid == -1)
 			err(1, "waitpid");
 		if (rpid != pid)
 			errx(1, "waitpid returned wrong pid"
 			    ": %"PRIdMAX" != %"PRIdMAX,
 			    (intmax_t)rpid,
 			    (intmax_t)pid);
 		if (WIFEXITED(status)) {
 			if (WEXITSTATUS(status) != 0)
 				errx(1, "child exited with %d",
 				    WEXITSTATUS(status));
 		} else if (WIFSIGNALED(status)) {
 			errx(1, "child terminated on signal %d",
 			    WTERMSIG(status));
 		} else {
 			errx(1, "child died mysteriously: %d", status);
+		}
+	}
+    }
 	/* XXX Test multithreaded fork safety...?  */
 	return 0;
+}
 #endif