aboutsummaryrefslogtreecommitdiff
path: root/drivers/char
diff options
context:
space:
mode:
authorStephan Mueller <smueller@chronox.de>2015-05-25 15:08:47 +0200
committerMister Oyster <oysterized@gmail.com>2017-04-11 10:59:06 +0200
commit8ee472b7d2c0f42bc7ee1b8ed86189f14d19d5ec (patch)
tree2d8584f8f1d76781be0a080f931464fa6877061b /drivers/char
parentff69231cd728b76d201ca685ccaf5a943de682cb (diff)
downloadandroid_kernel_m2note-8ee472b7d2c0f42bc7ee1b8ed86189f14d19d5ec.tar.gz
random: Blocking API for accessing nonblocking_pool
The added API calls provide a synchronous function call get_blocking_random_bytes where the caller is blocked until the nonblocking_pool is initialized. CC: Andreas Steffen <andreas.steffen@strongswan.org> CC: Theodore Ts'o <tytso@mit.edu> CC: Sandy Harris <sandyinchina@gmail.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/random.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 91ecb29b1..6fb78421f 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1249,6 +1249,18 @@ void get_random_bytes(void *buf, int nbytes)
EXPORT_SYMBOL(get_random_bytes);
/*
+ * Equivalent function to get_random_bytes with the difference that this
+ * function blocks the request until the nonblocking_pool is initialized.
+ */
+void get_blocking_random_bytes(void *buf, int nbytes)
+{
+ if (unlikely(nonblocking_pool.initialized == 0))
+ wait_event(urandom_init_wait, nonblocking_pool.initialized);
+ extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0);
+}
+EXPORT_SYMBOL(get_blocking_random_bytes);
+
+/*
* This function will use the architecture-specific hardware random
* number generator if it is available. The arch-specific hw RNG will
* almost certainly be faster than what we can do in software, but it