diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/char/random.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 8c7444857a4b..d8a9255e1a3f 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -240,6 +240,7 @@ #include <linux/spinlock.h> #include <linux/percpu.h> #include <linux/cryptohash.h> +#include <linux/fips.h> #ifdef CONFIG_GENERIC_HARDIRQS # include <linux/irq.h> @@ -413,6 +414,7 @@ struct entropy_store { unsigned add_ptr; int entropy_count; int input_rotate; + __u8 *last_data; }; static __u32 input_pool_data[INPUT_POOL_WORDS]; @@ -852,12 +854,21 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf, { ssize_t ret = 0, i; __u8 tmp[EXTRACT_SIZE]; + unsigned long flags; xfer_secondary_pool(r, nbytes); nbytes = account(r, nbytes, min, reserved); while (nbytes) { extract_buf(r, tmp); + + if (r->last_data) { + spin_lock_irqsave(&r->lock, flags); + if (!memcmp(tmp, r->last_data, EXTRACT_SIZE)) + panic("Hardware RNG duplicated output!\n"); + memcpy(r->last_data, tmp, EXTRACT_SIZE); + spin_unlock_irqrestore(&r->lock, flags); + } i = min_t(int, nbytes, EXTRACT_SIZE); memcpy(buf, tmp, i); nbytes -= i; @@ -940,6 +951,9 @@ static void init_std_data(struct entropy_store *r) now = ktime_get_real(); mix_pool_bytes(r, &now, sizeof(now)); mix_pool_bytes(r, utsname(), sizeof(*(utsname()))); + /* Enable continuous test in fips mode */ + if (fips_enabled) + r->last_data = kmalloc(EXTRACT_SIZE, GFP_KERNEL); } static int rand_initialize(void) |