Remove unused test code.

- make naming consistent with the kernel module.
- better distribution of functionality from src/wireguard.rs
- more consistent "import pattern" throughout the project.
- remove unused test code.

1 files changed, 35 insertions, 4 deletions

diff --git a/src/wireguard/constants.rs b/src/wireguard/constants.rs
index 97ce6b1..4d0ae54 100644
--- a/src/wireguard/constants.rs
+++ b/src/wireguard/constants.rs
@@ -10,17 +10,48 @@ pub const REKEY_ATTEMPT_TIME: Duration = Duration::from_secs(90);
 pub const REKEY_TIMEOUT: Duration = Duration::from_secs(5);
 pub const KEEPALIVE_TIMEOUT: Duration = Duration::from_secs(10);
 
-pub const MAX_TIMER_HANDSHAKES: usize = 18;
+pub const MAX_TIMER_HANDSHAKES: usize =
+    (REKEY_ATTEMPT_TIME.as_secs() / REKEY_TIMEOUT.as_secs()) as usize;
 
+// Semantics:
+// Maximum number of buffered handshake requests
+// (either from outside message or handshake requests triggered locally)
+pub const MAX_QUEUED_INCOMING_HANDSHAKES: usize = 4096;
+
+// Semantics:
+// When the number of queued handshake requests exceeds this number
+// the device is considered under load and DoS mitigation is triggered.
+pub const THRESHOLD_UNDER_LOAD: usize = MAX_QUEUED_INCOMING_HANDSHAKES / 8;
+
+// Semantics:
+// When a device is detected to go under load,
+// it will remain under load for at least the following duration.
+pub const DURATION_UNDER_LOAD: Duration = Duration::from_secs(1);
+
+// Semantics:
+// The payload of transport messages are padded to this multiple
+pub const MESSAGE_PADDING_MULTIPLE: usize = 16;
+
+// Semantics:
+// Longest possible duration of any WireGuard timer
 pub const TIMER_MAX_DURATION: Duration = Duration::from_secs(200);
+
+// Semantics:
+// Resolution of the timer-wheel
 pub const TIMERS_TICK: Duration = Duration::from_millis(100);
+
+// Semantics:
+// Resulting number of slots in the wheel
 pub const TIMERS_SLOTS: usize = (TIMER_MAX_DURATION.as_micros() / TIMERS_TICK.as_micros()) as usize;
-pub const TIMERS_CAPACITY: usize = 1024;
 
-pub const MESSAGE_PADDING_MULTIPLE: usize = 16;
+// Performance:
+// Initial capacity of timer-wheel (grows to accommodate more timers)
+pub const TIMERS_CAPACITY: usize = 16;
 
 /* A long duration (compared to the WireGuard time constants),
  * used in places to avoid Option<Instant> by instead using a long "expired" Instant:
  * (Instant::now() - TIME_HORIZON)
+ *
+ * Note, this duration need not fit inside the timer wheel.
  */
-pub const TIME_HORIZON: Duration = Duration::from_secs(60 * 60 * 24);
+pub const TIME_HORIZON: Duration = Duration::from_secs(TIMER_MAX_DURATION.as_secs() * 2);