diff options
Diffstat (limited to 'drivers/char/random.c')
-rw-r--r-- | drivers/char/random.c | 22 |
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); |