diff options
| author |   Stephan Mueller <smueller@chronox.de> | 2015-05-25 15:08:47 +0200 |
|---|---|---|
| committer |   Herbert Xu <herbert@gondor.apana.org.au> | 2015-05-27 17:51:53 +0800 |
| commit | 16b369a91d0dd80be214b7f7801fbc51875454cc (patch) | |
| tree | 651637281b51655197049065eeba784d3404ac6b | |
| parent | random: Wake up all getrandom(2) callers when pool is ready (diff) | |
| download | linux-dev-16b369a91d0dd80be214b7f7801fbc51875454cc.tar.xz linux-dev-16b369a91d0dd80be214b7f7801fbc51875454cc.zip | |
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>
| -rw-r--r-- | drivers/char/random.c | 12 | ||||
| -rw-r--r-- | include/linux/random.h | 1 |
2 files changed, 13 insertions, 0 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 8b8c46b5fd5c..159d0700f7d8 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1245,6 +1245,18 @@ 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 diff --git a/include/linux/random.h b/include/linux/random.h index b05856e16b75..796267d56901 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -14,6 +14,7 @@ extern void add_input_randomness(unsigned int type, unsigned int code, extern void add_interrupt_randomness(int irq, int irq_flags); extern void get_random_bytes(void *buf, int nbytes); +extern void get_blocking_random_bytes(void *buf, int nbytes); extern void get_random_bytes_arch(void *buf, int nbytes); void generate_random_uuid(unsigned char uuid_out[16]); extern int random_int_secret_init(void); |