#include <linux/jiffies.h>
#include <linux/random.h>
#include <linux/sched.h>
+#include <asm/unaligned.h>
#ifdef CONFIG_RANDOM32_SELFTEST
static void __init prandom_state_selftest(void);
* This is used for pseudo-randomness with no outside seeding.
* For more random results, use prandom_bytes().
*/
-void prandom_bytes_state(struct rnd_state *state, void *buf, int bytes)
+void prandom_bytes_state(struct rnd_state *state, void *buf, size_t bytes)
{
- unsigned char *p = buf;
- int i;
-
- for (i = 0; i < round_down(bytes, sizeof(u32)); i += sizeof(u32)) {
- u32 random = prandom_u32_state(state);
- int j;
+ u8 *ptr = buf;
- for (j = 0; j < sizeof(u32); j++) {
- p[i + j] = random;
- random >>= BITS_PER_BYTE;
- }
+ while (bytes >= sizeof(u32)) {
+ put_unaligned(prandom_u32_state(state), (u32 *) ptr);
+ ptr += sizeof(u32);
+ bytes -= sizeof(u32);
}
- if (i < bytes) {
- u32 random = prandom_u32_state(state);
- for (; i < bytes; i++) {
- p[i] = random;
- random >>= BITS_PER_BYTE;
- }
+ if (bytes > 0) {
+ u32 rem = prandom_u32_state(state);
+ do {
+ *ptr++ = (u8) rem;
+ bytes--;
+ rem >>= BITS_PER_BYTE;
+ } while (bytes > 0);
}
}
EXPORT_SYMBOL(prandom_bytes_state);
* @buf: where to copy the pseudo-random bytes to
* @bytes: the requested number of bytes
*/
-void prandom_bytes(void *buf, int bytes)
+void prandom_bytes(void *buf, size_t bytes)
{
struct rnd_state *state = &get_cpu_var(net_rand_state);
static void prandom_warmup(struct rnd_state *state)
{
- /* Calling RNG ten times to satify recurrence condition */
+ /* Calling RNG ten times to satisfy recurrence condition */
prandom_u32_state(state);
prandom_u32_state(state);
prandom_u32_state(state);
static u32 __extract_hwseed(void)
{
- u32 val = 0;
+ unsigned int val = 0;
(void)(arch_get_random_seed_int(&val) ||
arch_get_random_int(&val));
* No locking on the CPUs, but then somewhat random results are, well,
* expected.
*/
- for_each_possible_cpu (i) {
+ for_each_possible_cpu(i) {
struct rnd_state *state = &per_cpu(net_rand_state, i);
state->s1 = __seed(state->s1 ^ entropy, 2U);
prandom_state_selftest();
for_each_possible_cpu(i) {
- struct rnd_state *state = &per_cpu(net_rand_state,i);
+ struct rnd_state *state = &per_cpu(net_rand_state, i);
u32 weak_seed = (i + jiffies) ^ random_get_entropy();
prandom_seed_early(state, weak_seed, true);
prandom_seed(entropy);
/* reseed every ~60 seconds, in [40 .. 80) interval with slack */
- expires = 40 + (prandom_u32() % 40);
+ expires = 40 + prandom_u32_max(40);
seed_timer.expires = jiffies + msecs_to_jiffies(expires * MSEC_PER_SEC);
add_timer(&seed_timer);
add_timer(&seed_timer);
}
+void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state)
+{
+ int i;
+
+ for_each_possible_cpu(i) {
+ struct rnd_state *state = per_cpu_ptr(pcpu_state, i);
+ u32 seeds[4];
+
+ get_random_bytes(&seeds, sizeof(seeds));
+ state->s1 = __seed(seeds[0], 2U);
+ state->s2 = __seed(seeds[1], 8U);
+ state->s3 = __seed(seeds[2], 16U);
+ state->s4 = __seed(seeds[3], 128U);
+
+ prandom_warmup(state);
+ }
+}
+
/*
* Generate better values after random number generator
* is fully initialized.
*/
static void __prandom_reseed(bool late)
{
- int i;
unsigned long flags;
static bool latch = false;
static DEFINE_SPINLOCK(lock);
goto out;
latch = true;
-
- for_each_possible_cpu(i) {
- struct rnd_state *state = &per_cpu(net_rand_state,i);
- u32 seeds[4];
-
- get_random_bytes(&seeds, sizeof(seeds));
- state->s1 = __seed(seeds[0], 2U);
- state->s2 = __seed(seeds[1], 8U);
- state->s3 = __seed(seeds[2], 16U);
- state->s4 = __seed(seeds[3], 128U);
-
- prandom_warmup(state);
- }
+ prandom_seed_full_state(&net_rand_state);
out:
spin_unlock_irqrestore(&lock, flags);
}