From 8566417221fcec51346ec164e920dacb979c6b5f Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Tue, 8 Feb 2022 12:40:14 +0100 Subject: [PATCH] random: inline leaves of rand_initialize() This is a preparatory commit for the following one. We simply inline the various functions that rand_initialize() calls that have no other callers. The compiler was doing this anyway before. Doing this will allow us to reorganize this after. We can then move the trust_cpu and parse_trust_cpu definitions a bit closer to where they're actually used, which makes the code easier to read. Cc: Theodore Ts'o Reviewed-by: Dominik Brodowski Reviewed-by: Eric Biggers Signed-off-by: Jason A. Donenfeld --- drivers/char/random.c | 92 ++++++++++++++++--------------------------- 1 file changed, 34 insertions(+), 58 deletions(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index be4922e09cc5..a55a58b9807a 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -476,42 +476,6 @@ static DECLARE_WAIT_QUEUE_HEAD(crng_init_wait); static void invalidate_batched_entropy(void); -static bool trust_cpu __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_CPU); -static int __init parse_trust_cpu(char *arg) -{ - return kstrtobool(arg, &trust_cpu); -} -early_param("random.trust_cpu", parse_trust_cpu); - -static bool __init crng_init_try_arch_early(void) -{ - int i; - bool arch_init = true; - unsigned long rv; - - for (i = 4; i < 16; i++) { - if (!arch_get_random_seed_long_early(&rv) && - !arch_get_random_long_early(&rv)) { - rv = random_get_entropy(); - arch_init = false; - } - primary_crng.state[i] ^= rv; - } - - return arch_init; -} - -static void __init crng_initialize(void) -{ - extract_entropy(&primary_crng.state[4], sizeof(u32) * 12); - if (crng_init_try_arch_early() && trust_cpu && crng_init < 2) { - invalidate_batched_entropy(); - crng_init = 2; - pr_notice("crng init done (trusting CPU's manufacturer)\n"); - } - primary_crng.init_time = jiffies - CRNG_RESEED_INTERVAL - 1; -} - /* * crng_fast_load() can be called by code in the interrupt service * path. So we can't afford to dilly-dally. Returns the number of @@ -1220,28 +1184,12 @@ int __must_check get_random_bytes_arch(void *buf, int nbytes) } EXPORT_SYMBOL(get_random_bytes_arch); -/* - * init_std_data - initialize pool with system data - * - * This function clears the pool's entropy count and mixes some system - * data into the pool to prepare it for use. The pool is not cleared - * as that can only decrease the entropy in the pool. - */ -static void __init init_std_data(void) +static bool trust_cpu __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_CPU); +static int __init parse_trust_cpu(char *arg) { - int i; - ktime_t now = ktime_get_real(); - unsigned long rv; - - mix_pool_bytes(&now, sizeof(now)); - for (i = BLAKE2S_BLOCK_SIZE; i > 0; i -= sizeof(rv)) { - if (!arch_get_random_seed_long(&rv) && - !arch_get_random_long(&rv)) - rv = random_get_entropy(); - mix_pool_bytes(&rv, sizeof(rv)); - } - mix_pool_bytes(utsname(), sizeof(*(utsname()))); + return kstrtobool(arg, &trust_cpu); } +early_param("random.trust_cpu", parse_trust_cpu); /* * Note that setup_arch() may call add_device_randomness() @@ -1255,8 +1203,36 @@ static void __init init_std_data(void) */ int __init rand_initialize(void) { - init_std_data(); - crng_initialize(); + int i; + ktime_t now = ktime_get_real(); + bool arch_init = true; + unsigned long rv; + + mix_pool_bytes(&now, sizeof(now)); + for (i = BLAKE2S_BLOCK_SIZE; i > 0; i -= sizeof(rv)) { + if (!arch_get_random_seed_long(&rv) && + !arch_get_random_long(&rv)) + rv = random_get_entropy(); + mix_pool_bytes(&rv, sizeof(rv)); + } + mix_pool_bytes(utsname(), sizeof(*(utsname()))); + + extract_entropy(&primary_crng.state[4], sizeof(u32) * 12); + for (i = 4; i < 16; i++) { + if (!arch_get_random_seed_long_early(&rv) && + !arch_get_random_long_early(&rv)) { + rv = random_get_entropy(); + arch_init = false; + } + primary_crng.state[i] ^= rv; + } + if (arch_init && trust_cpu && crng_init < 2) { + invalidate_batched_entropy(); + crng_init = 2; + pr_notice("crng init done (trusting CPU's manufacturer)\n"); + } + primary_crng.init_time = jiffies - CRNG_RESEED_INTERVAL - 1; + if (ratelimit_disable) { urandom_warning.interval = 0; unseeded_warning.interval = 0;