triple-check-everything-before-code-freeze

Author: crypto-vincent

architectures/decentralized/solana-distributor/programs/solana-distributor/src/lib.rs

@@ -54,6 +54,4 @@ pub enum ProgramError {
     ParamsMerkleProofIsInvalid,
     #[msg("params.collateral_amount is too large")]
     ParamsCollateralAmountIsTooLarge,
-    #[msg("math overflow")]
-    MathOverflow,
 }

architectures/decentralized/solana-distributor/programs/solana-distributor/src/logic/airdrop_withdraw.rs

@@ -57,6 +57,7 @@ pub fn airdrop_withdraw_processor(
     params: AirdropWithdrawParams,
 ) -> Result<()> {
     let airdrop = &mut context.accounts.airdrop;
+
     let airdrop_signer_seeds: &[&[&[u8]]] = &[&[
         Airdrop::SEEDS_PREFIX,
         &airdrop.id.to_le_bytes(),

architectures/decentralized/solana-distributor/programs/solana-distributor/src/logic/claim_redeem.rs

@@ -89,9 +89,9 @@ pub fn claim_redeem_processor(
     let claim = &mut context.accounts.claim;
     let claimable_collateral_amount = params
         .vesting
-        .compute_vested_collateral_amount(Clock::get()?.unix_timestamp)?
-        .saturating_sub(i128::from(claim.claimed_collateral_amount));
-    if claimable_collateral_amount < i128::from(params.collateral_amount) {
+        .compute_vested_collateral_amount(Clock::get()?.unix_timestamp)
+        - claim.claimed_collateral_amount;
+    if claimable_collateral_amount < params.collateral_amount {
         return err!(ProgramError::ParamsCollateralAmountIsTooLarge);
     }
     claim.claimed_collateral_amount += params.collateral_amount;

architectures/decentralized/solana-distributor/programs/solana-distributor/src/state/vesting.rs

@@ -1,7 +1,5 @@
 use anchor_lang::prelude::*;
 
-use crate::ProgramError;
-
 #[derive(Debug, InitSpace, AnchorSerialize, AnchorDeserialize, Clone, Copy)]
 pub struct Vesting {
     pub start_unix_timestamp: i64,
@@ -13,20 +11,26 @@ impl Vesting {
     pub fn compute_vested_collateral_amount(
         &self,
         now_unix_timestamp: i64,
-    ) -> Result<i128> {
-        let elapsed_seconds = now_unix_timestamp
-            .checked_sub(self.start_unix_timestamp)
-            .ok_or(ProgramError::MathOverflow)?;
-        if elapsed_seconds < 0 {
-            return Ok(0);
+    ) -> u64 {
+        if now_unix_timestamp < self.start_unix_timestamp {
+            return 0;
         }
-        if elapsed_seconds >= i64::from(self.duration_seconds) {
-            return Ok(i128::from(self.end_collateral_amount));
+        if self.duration_seconds == 0 {
+            return self.end_collateral_amount;
         }
-        Ok(i128::from(self.end_collateral_amount)
-            .checked_mul(i128::from(elapsed_seconds))
-            .ok_or(ProgramError::MathOverflow)?
-            .checked_div(i128::from(self.duration_seconds))
-            .ok_or(ProgramError::MathOverflow)?)
+
+        let elapsed_seconds =
+            u128::try_from(now_unix_timestamp - self.start_unix_timestamp)
+                .unwrap();
+        let duration_seconds = u128::from(self.duration_seconds);
+        let end_collateral_amount = u128::from(self.end_collateral_amount);
+
+        let vested_collateral_amount =
+            end_collateral_amount * elapsed_seconds / duration_seconds;
+        if vested_collateral_amount > end_collateral_amount {
+            return self.end_collateral_amount;
+        }
+
+        u64::try_from(vested_collateral_amount).unwrap()
     }
 }