return 0;
}
-/* There is one of these per entropy source */
-struct timer_rand_state {
- cycles_t last_time;
- long last_delta, last_delta2;
-};
-
/*
* Add device- or boot-specific data to the input pool to help
* initialize it.
*/
void add_device_randomness(const void *buf, size_t size)
{
- unsigned long time = random_get_entropy() ^ jiffies;
- unsigned long flags;
+ cycles_t cycles = random_get_entropy();
+ unsigned long flags, now = jiffies;
if (crng_init == 0 && size)
crng_pre_init_inject(buf, size, false, false);
spin_lock_irqsave(&input_pool.lock, flags);
+ _mix_pool_bytes(&cycles, sizeof(cycles));
+ _mix_pool_bytes(&now, sizeof(now));
_mix_pool_bytes(buf, size);
- _mix_pool_bytes(&time, sizeof(time));
spin_unlock_irqrestore(&input_pool.lock, flags);
}
EXPORT_SYMBOL(add_device_randomness);
+/* There is one of these per entropy source */
+struct timer_rand_state {
+ unsigned long last_time;
+ long last_delta, last_delta2;
+};
+
/*
* This function adds entropy to the entropy "pool" by using timing
* delays. It uses the timer_rand_state structure to make an estimate
* 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.
- *
*/
static void add_timer_randomness(struct timer_rand_state *state, unsigned int num)
{
- struct {
- long jiffies;
- unsigned int cycles;
- unsigned int num;
- } sample;
+ cycles_t cycles = random_get_entropy();
+ unsigned long flags, now = jiffies;
long delta, delta2, delta3;
- sample.jiffies = jiffies;
- sample.cycles = random_get_entropy();
- sample.num = num;
- mix_pool_bytes(&sample, sizeof(sample));
+ spin_lock_irqsave(&input_pool.lock, flags);
+ _mix_pool_bytes(&cycles, sizeof(cycles));
+ _mix_pool_bytes(&now, sizeof(now));
+ _mix_pool_bytes(&num, sizeof(num));
+ spin_unlock_irqrestore(&input_pool.lock, flags);
/*
* Calculate number of bits of randomness we probably added.
* We take into account the first, second and third-order deltas
* in order to make our estimate.
*/
- delta = sample.jiffies - READ_ONCE(state->last_time);
- WRITE_ONCE(state->last_time, sample.jiffies);
+ delta = now - READ_ONCE(state->last_time);
+ WRITE_ONCE(state->last_time, now);
delta2 = delta - READ_ONCE(state->last_delta);
WRITE_ONCE(state->last_delta, delta);
void add_interrupt_randomness(int irq)
{
enum { MIX_INFLIGHT = 1U << 31 };
+ cycles_t cycles = random_get_entropy();
+ unsigned long now = jiffies;
struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness);
struct pt_regs *regs = get_irq_regs();
- unsigned long now = jiffies;
- cycles_t cycles = random_get_entropy();
unsigned int new_count;
if (cycles == 0)
static void try_to_generate_entropy(void)
{
struct {
- unsigned long now;
+ cycles_t cycles;
struct timer_list timer;
} stack;
- stack.now = random_get_entropy();
+ stack.cycles = random_get_entropy();
/* Slow counter - or none. Don't even bother */
- if (stack.now == random_get_entropy())
+ if (stack.cycles == random_get_entropy())
return;
timer_setup_on_stack(&stack.timer, entropy_timer, 0);
while (!crng_ready()) {
if (!timer_pending(&stack.timer))
mod_timer(&stack.timer, jiffies + 1);
- mix_pool_bytes(&stack.now, sizeof(stack.now));
+ mix_pool_bytes(&stack.cycles, sizeof(stack.cycles));
schedule();
- stack.now = random_get_entropy();
+ stack.cycles = random_get_entropy();
}
del_timer_sync(&stack.timer);
destroy_timer_on_stack(&stack.timer);
- mix_pool_bytes(&stack.now, sizeof(stack.now));
+ mix_pool_bytes(&stack.cycles, sizeof(stack.cycles));
}