Fix blocked entropy generation

The OpenWrt Jitter RNG daemon is currently unable to continuously
provide entropy, except once on process startup.

This patch brings the following fixes:
- poll /dev/random for unblocking write operations, instead of read
- register the low entropy callback after uloop initialization, not
  before

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
[commit subject tweak, uloop_done cleanup]
Signed-off-by: Petr Štetiar <ynezz@true.cz>

1 files changed, 5 insertions, 3 deletions

diff --git a/urngd.c b/urngd.c
index d8ed159..35ccdec 100644
--- a/urngd.c
+++ b/urngd.c
@@ -180,7 +180,7 @@ static bool urngd_init(struct urngd *u)
 		return false;
 	}
 
-	uloop_fd_add(&u->rnd_fd, ULOOP_READ);
+	uloop_fd_add(&u->rnd_fd, ULOOP_WRITE);
 
 	return true;
 }
@@ -227,14 +227,16 @@ int main(int argc, char **argv)
 
 	ulog_open(ulog_channels, LOG_DAEMON, "urngd");
 
-	if (!urngd_init(&urngd_service))
+	uloop_init();
+	if (!urngd_init(&urngd_service)) {
+		uloop_done();
 		return -1;
+	}
 
 	LOG("v%s started.\n", URNGD_VERSION);
 
 	gather_entropy(&urngd_service);
 
-	uloop_init();
 	uloop_run();
 	uloop_done();