Implement priority message

Author: HoOngEe

core/src/consensus/sortition/mod.rs

@@ -17,3 +17,36 @@
 mod binom_cdf;
 mod lot;
 mod vrf_sortition;
+
+use ckey::Public;
+use primitives::H256;
+use vrf::openssl::Error as VrfError;
+
+use self::vrf_sortition::Priority;
+use self::vrf_sortition::VRFSortition;
+
+pub struct PriorityMessage {
+    pub seed: H256,
+    pub priority: Priority,
+    pub vrf_hash: Vec<u8>,
+    pub vrf_proof: Vec<u8>,
+    pub sub_user_index: u64,
+    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> {
+        Ok(sortition_scheme.verify_sub_user_idx(voting_power, &self.vrf_hash, self.sub_user_index)
+            && sortition_scheme.verify_priority(&self.vrf_hash, self.sub_user_index, &self.priority)
+            && sortition_scheme.verify_vrf_hash(signer_public, &self.vrf_proof, &self.seed, &self.vrf_hash)?)
+    }
+}

core/src/consensus/sortition/vrf_sortition.rs

@@ -80,12 +80,7 @@ impl VRFSortition {
         Ok(verified_hash == vrf_hash)
     }
 
-    pub fn verify_sub_user_idx(
-        &self,
-        voting_power: u64,
-        vrf_hash: &[u8],
-        sub_user_idx: u64,
-    ) -> bool {
+    pub fn verify_sub_user_idx(&self, voting_power: u64, vrf_hash: &[u8], sub_user_idx: u64) -> bool {
         let j = lot(voting_power, self.total_power, self.expectaion, vrf_hash);
         sub_user_idx < j
     }

core/src/lib.rs

@@ -55,6 +55,7 @@ extern crate snap;
 extern crate statrs;
 extern crate table;
 extern crate util_error;
+extern crate vrf;
 #[macro_use]
 extern crate log;
 extern crate core;