ath9k: Mix the received FFT bins to the random pool
E/M noise is a pretty good source of entropy so we mix the FFT
measurements of the E/M spectrum to /dev/random pool. Note that
this doesn't increase the pool's entropy count but it still helps
on improving the output of /dev/(u)random.
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
diff --git a/drivers/net/wireless/ath/ath9k/common-spectral.c b/drivers/net/wireless/ath/ath9k/common-spectral.c
index 5840b37..a876271 100644
--- a/drivers/net/wireless/ath/ath9k/common-spectral.c
+++ b/drivers/net/wireless/ath/ath9k/common-spectral.c
@@ -15,6 +15,7 @@
*/
#include <linux/relay.h>
+#include <linux/random.h>
#include "ath9k.h"
static s8 fix_rssi_inv_only(u8 rssi_val)
@@ -647,13 +648,24 @@
tsf, freq, chan_type);
memset(sample_buf, 0, SPECTRAL_SAMPLE_MAX_LEN);
+
+ /* Mix the received bins to the /dev/random
+ * pool
+ */
+ add_device_randomness(sample_buf, num_bins);
}
/* Process a normal frame */
- if (sample_bytes == sample_len)
+ if (sample_bytes == sample_len) {
ret = fft_handler(rs, spec_priv, sample_start,
tsf, freq, chan_type);
+ /* Mix the received bins to the /dev/random
+ * pool
+ */
+ add_device_randomness(sample_start, num_bins);
+ }
+
/* Short report processed, break out of the
* loop.
*/