summaryrefslogtreecommitdiff
path: root/drivers/char/random.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/char/random.c')
-rw-r--r--drivers/char/random.c22
1 files changed, 17 insertions, 5 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 66ce7c03a142..1d8242969751 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -224,9 +224,10 @@ static void _warn_unseeded_randomness(const char *func_name, void *caller, void
*
* These interfaces will return the requested number of random bytes
* into the given buffer or as a return value. This is equivalent to
- * a read from /dev/urandom. The integer family of functions may be
- * higher performance for one-off random integers, because they do a
- * bit of buffering.
+ * a read from /dev/urandom. The u32, u64, int, and long family of
+ * functions may be higher performance for one-off random integers,
+ * because they do a bit of buffering and do not invoke reseeding
+ * until the buffer is emptied.
*
*********************************************************************/
@@ -948,11 +949,17 @@ static bool drain_entropy(void *buf, size_t nbytes, bool force)
**********************************************************************/
static bool trust_cpu __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_CPU);
+static bool trust_bootloader __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_BOOTLOADER);
static int __init parse_trust_cpu(char *arg)
{
return kstrtobool(arg, &trust_cpu);
}
+static int __init parse_trust_bootloader(char *arg)
+{
+ return kstrtobool(arg, &trust_bootloader);
+}
early_param("random.trust_cpu", parse_trust_cpu);
+early_param("random.trust_bootloader", parse_trust_bootloader);
/*
* The first collection of entropy occurs at system boot while interrupts
@@ -968,6 +975,11 @@ int __init rand_initialize(void)
bool arch_init = true;
unsigned long rv;
+#if defined(LATENT_ENTROPY_PLUGIN)
+ static const u8 compiletime_seed[BLAKE2S_BLOCK_SIZE] __initconst __latent_entropy;
+ _mix_pool_bytes(compiletime_seed, sizeof(compiletime_seed));
+#endif
+
for (i = 0; i < BLAKE2S_BLOCK_SIZE; i += sizeof(rv)) {
if (!arch_get_random_seed_long_early(&rv) &&
!arch_get_random_long_early(&rv)) {
@@ -1128,7 +1140,7 @@ void rand_initialize_disk(struct gendisk *disk)
void add_hwgenerator_randomness(const void *buffer, size_t count,
size_t entropy)
{
- if (unlikely(crng_init == 0)) {
+ if (unlikely(crng_init == 0 && entropy < POOL_MIN_BITS)) {
size_t ret = crng_pre_init_inject(buffer, count, true);
mix_pool_bytes(buffer, ret);
count -= ret;
@@ -1160,7 +1172,7 @@ EXPORT_SYMBOL_GPL(add_hwgenerator_randomness);
*/
void add_bootloader_randomness(const void *buf, size_t size)
{
- if (IS_ENABLED(CONFIG_RANDOM_TRUST_BOOTLOADER))
+ if (trust_bootloader)
add_hwgenerator_randomness(buf, size, size * 8);
else
add_device_randomness(buf, size);