Implement priority message

Author: HoOngEe

core/src/consensus/sortition/mod.rs

@@ -17,3 +17,35 @@
 mod binom_cdf;
 mod lot;
 mod vrf_sortition;
+
+use std::sync::Arc;
+
+use ckey::Public;
+use primitives::H256;
+use vrf::openssl::Error as VrfError;
+
+use self::vrf_sortition::{PriorityInfo, VRFSortition};
+
+pub struct PriorityMessage {
+    pub seed: H256,
+    pub info: PriorityInfo,
+    pub signer_index: usize,
+}
+
+impl PriorityMessage {
+    pub fn signer_index(&self) -> usize {
+        self.signer_index
+    }
+
+    pub fn verify(
+        &self,
+        signer_public: &Public,
+        voting_power: u64,
+        sortition_scheme: &VRFSortition,
+    ) -> Result<bool, VrfError> {
+        // fast verification first
+        Ok(self.info.verify_sub_user_idx(voting_power, sortition_scheme.total_power, sortition_scheme.expectation)
+            && self.info.verify_priority()
+            && self.info.verify_vrf_hash(signer_public, &self.seed, Arc::clone(&sortition_scheme.vrf_inst))?)
+    }
+}