diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2018-04-11 16:32:17 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-24 09:34:16 +0200 |
| commit | 1d49e2ab766df649c540959a96f1ab839471fbe8 (patch) | |
| tree | 9328742bd0fa967f93899cbd3d7a4f2af3637f02 /drivers/char | |
| parent | befd00cfc189672adfdf6850cf460a7f53c56cf0 (diff) | |
random: add new ioctl RNDRESEEDCRNG
commit d848e5f8e1ebdb227d045db55fe4f825e82965fa upstream.
Add a new ioctl which forces the the crng to be reseeded.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/random.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 9d24f3cdc9bb..8d08a8062904 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -436,6 +436,7 @@ struct crng_state primary_crng = { static int crng_init = 0; #define crng_ready() (likely(crng_init > 1)) static int crng_init_cnt = 0; +static unsigned long crng_global_init_time = 0; #define CRNG_INIT_CNT_THRESH (2*CHACHA20_KEY_SIZE) static void _extract_crng(struct crng_state *crng, __u8 out[CHACHA20_BLOCK_SIZE]); @@ -873,7 +874,8 @@ static void _extract_crng(struct crng_state *crng, unsigned long v, flags; if (crng_ready() && - time_after(jiffies, crng->init_time + CRNG_RESEED_INTERVAL)) + (time_after(crng_global_init_time, crng->init_time) || + time_after(jiffies, crng->init_time + CRNG_RESEED_INTERVAL))) crng_reseed(crng, crng == &primary_crng ? &input_pool : NULL); spin_lock_irqsave(&crng->lock, flags); if (arch_get_random_long(&v)) @@ -1668,6 +1670,7 @@ static int rand_initialize(void) init_std_data(&input_pool); init_std_data(&blocking_pool); crng_initialize(&primary_crng); + crng_global_init_time = jiffies; #ifdef CONFIG_NUMA pool = kcalloc(nr_node_ids, sizeof(*pool), GFP_KERNEL|__GFP_NOFAIL); @@ -1854,6 +1857,14 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg) input_pool.entropy_count = 0; blocking_pool.entropy_count = 0; return 0; + case RNDRESEEDCRNG: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (crng_init < 2) + return -ENODATA; + crng_reseed(&primary_crng, NULL); + crng_global_init_time = jiffies - 1; + return 0; default: return -EINVAL; } |