rng: switch to /dev/urandom

There's no need to provide direct access to /dev/random to all guests,
and we don't want them to be able to drain entropy from other VMs and
from the host itself.

BUG=chromium:800520
TEST=precq passes

Change-Id: I94ea0755123ee7479ca83c07525ca870d42c637f
Reviewed-on: https://chromium-review.googlesource.com/872890
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
Reviewed-by: Zach Reizner <zachr@chromium.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/devices/src/virtio/rng.rs b/devices/src/virtio/rng.rs
index da5d40b..7bf6410 100644
--- a/devices/src/virtio/rng.rs
+++ b/devices/src/virtio/rng.rs
@@ -19,7 +19,7 @@ const QUEUE_SIZES: &'static [u16] = &[QUEUE_SIZE];
 
 #[derive(Debug)]
 pub enum RngError {
-    /// Can't access /dev/random
+    /// Can't access /dev/urandom
     AccessingRandomDev(io::Error),
 }
 pub type Result<T> = std::result::Result<T, RngError>;
@@ -110,9 +110,9 @@ pub struct Rng {
 }
 
 impl Rng {
-    /// Create a new virtio rng device that gets random data from /dev/random.
+    /// Create a new virtio rng device that gets random data from /dev/urandom.
     pub fn new() -> Result<Rng> {
-        let random_file = File::open("/dev/random")
+        let random_file = File::open("/dev/urandom")
             .map_err(RngError::AccessingRandomDev)?;
         Ok(Rng {
                kill_evt: None,