clean up and extend mint/burn account infos

Author: samkim-crypto

token/confidential-transfer/proof-generation/src/burn.rs

@@ -36,9 +36,12 @@ pub fn burn_split_proof_data(
     burn_amount: u64,
     source_elgamal_keypair: &ElGamalKeypair,
     source_aes_key: &AeKey,
-    auditor_elgamal_pubkey: &ElGamalPubkey,
+    auditor_elgamal_pubkey: Option<&ElGamalPubkey>,
     supply_elgamal_pubkey: &ElGamalPubkey,
 ) -> Result<BurnProofData, TokenProofGenerationError> {
+    let default_auditor_pubkey = ElGamalPubkey::default();
+    let auditor_elgamal_pubkey = auditor_elgamal_pubkey.unwrap_or(&default_auditor_pubkey);
+
     // split the burn amount into low and high bits
     let (burn_amount_lo, burn_amount_hi) = try_split_u64(burn_amount, BURN_AMOUNT_LO_BIT_LENGTH)
         .ok_or(TokenProofGenerationError::IllegalAmountBitLength)?;

token/confidential-transfer/proof-generation/src/mint.rs

@@ -38,8 +38,11 @@ pub fn mint_split_proof_data(
     supply_elgamal_keypair: &ElGamalKeypair,
     supply_aes_key: &AeKey,
     destination_elgamal_pubkey: &ElGamalPubkey,
-    auditor_elgamal_pubkey: &ElGamalPubkey,
+    auditor_elgamal_pubkey: Option<&ElGamalPubkey>,
 ) -> Result<MintProofData, TokenProofGenerationError> {
+    let default_auditor_pubkey = ElGamalPubkey::default();
+    let auditor_elgamal_pubkey = auditor_elgamal_pubkey.unwrap_or(&default_auditor_pubkey);
+
     // split the mint amount into low and high bits
     let (mint_amount_lo, mint_amount_hi) = try_split_u64(mint_amount, MINT_AMOUNT_LO_BIT_LENGTH)
         .ok_or(TokenProofGenerationError::IllegalAmountBitLength)?;

token/confidential-transfer/proof-tests/tests/proof_test.rs

@@ -238,7 +238,7 @@ fn test_mint_validity(mint_amount: u64, supply: u64) {
         &supply_keypair,
         &supply_aes_key,
         destination_pubkey,
-        auditor_pubkey,
+        Some(auditor_pubkey),
     )
     .unwrap();
 
@@ -291,7 +291,7 @@ fn test_burn_validity(spendable_balance: u64, burn_amount: u64) {
         burn_amount,
         &source_keypair,
         &aes_key,
-        auditor_pubkey,
+        Some(auditor_pubkey),
         supply_pubkey,
     )
     .unwrap();

token/program-2022/src/extension/confidential_mint_burn/account_info.rs

@@ -1,11 +1,16 @@
 use {
     super::ConfidentialMintBurn,
-    crate::error::TokenError,
+    crate::{
+        error::TokenError,
+        extension::confidential_transfer::{
+            ConfidentialTransferAccount, DecryptableBalance, EncryptedBalance,
+        },
+    },
     bytemuck::{Pod, Zeroable},
     solana_zk_sdk::{
         encryption::{
             auth_encryption::{AeCiphertext, AeKey},
-            elgamal::{ElGamalCiphertext, ElGamalKeypair},
+            elgamal::{ElGamalCiphertext, ElGamalKeypair, ElGamalPubkey},
             pedersen::PedersenOpening,
             pod::{
                 auth_encryption::PodAeCiphertext,
@@ -14,6 +19,10 @@ use {
         },
         zk_elgamal_proof_program::proof_data::CiphertextCiphertextEqualityProofData,
     },
+    spl_token_confidential_transfer_proof_generation::{
+        burn::{burn_split_proof_data, BurnProofData},
+        mint::{mint_split_proof_data, MintProofData},
+    },
 };
 
 /// Confidential Mint Burn extension information needed to construct a
@@ -102,4 +111,85 @@ impl SupplyAccountInfo {
         )
         .map_err(|_| TokenError::ProofGeneration)
     }
+
+    /// Create a mint proof data that is split into equality, ciphertext
+    /// validity, and range proof.
+    pub fn generate_split_mint_proof_data(
+        &self,
+        mint_amount: u64,
+        current_supply: u64,
+        supply_elgamal_keypair: &ElGamalKeypair,
+        aes_key: &AeKey,
+        destination_elgamal_pubkey: &ElGamalPubkey,
+        auditor_elgamal_pubkey: Option<&ElGamalPubkey>,
+    ) -> Result<MintProofData, TokenError> {
+        let current_supply_ciphertext = self
+            .current_supply
+            .try_into()
+            .map_err(|_| TokenError::MalformedCiphertext)?;
+
+        mint_split_proof_data(
+            &current_supply_ciphertext,
+            mint_amount,
+            current_supply,
+            supply_elgamal_keypair,
+            aes_key,
+            destination_elgamal_pubkey,
+            auditor_elgamal_pubkey,
+        )
+        .map_err(|e| -> TokenError { e.into() })
+    }
+}
+
+/// Confidential Mint Burn extension information needed to construct a
+/// `Burn` instruction.
+#[repr(C)]
+#[derive(Clone, Copy, Debug, Default, PartialEq, Pod, Zeroable)]
+pub struct BurnAccountInfo {
+    /// The available balance (encrypted by `encryption_pubkey`)
+    pub available_balance: EncryptedBalance,
+    /// The decryptable available balance
+    pub decryptable_available_balance: DecryptableBalance,
+}
+
+impl BurnAccountInfo {
+    /// Create the `ApplyPendingBalance` instruction account information from
+    /// `ConfidentialTransferAccount`.
+    pub fn new(account: &ConfidentialTransferAccount) -> Self {
+        Self {
+            available_balance: account.available_balance,
+            decryptable_available_balance: account.decryptable_available_balance,
+        }
+    }
+
+    /// Create a burn proof data that is split into equality, ciphertext
+    /// validity, and range proof.
+    pub fn generate_split_burn_proof_data(
+        &self,
+        burn_amount: u64,
+        source_elgamal_keypair: &ElGamalKeypair,
+        aes_key: &AeKey,
+        auditor_elgamal_pubkey: Option<&ElGamalPubkey>,
+        supply_elgamal_pubkey: &ElGamalPubkey,
+    ) -> Result<BurnProofData, TokenError> {
+        let current_available_balance_ciphertext = self
+            .available_balance
+            .try_into()
+            .map_err(|_| TokenError::MalformedCiphertext)?;
+        let current_decryptable_available_balance = self
+            .decryptable_available_balance
+            .try_into()
+            .map_err(|_| TokenError::MalformedCiphertext)?;
+
+        burn_split_proof_data(
+            &current_available_balance_ciphertext,
+            &current_decryptable_available_balance,
+            burn_amount,
+            source_elgamal_keypair,
+            aes_key,
+            auditor_elgamal_pubkey,
+            supply_elgamal_pubkey,
+        )
+        .map_err(|e| -> TokenError { e.into() })
+    }
 }

token/program-2022/src/extension/confidential_transfer/account_info.rs

@@ -147,7 +147,7 @@ impl ApplyPendingBalanceAccountInfo {
 #[repr(C)]
 #[derive(Clone, Copy, Debug, Default, PartialEq, Pod, Zeroable)]
 pub struct WithdrawAccountInfo {
-    /// The available balance (encrypted by `encrypiton_pubkey`)
+    /// The available balance (encrypted by `encryption_pubkey`)
     pub available_balance: EncryptedBalance,
     /// The decryptable available balance
     pub decryptable_available_balance: DecryptableBalance,
@@ -214,7 +214,7 @@ impl WithdrawAccountInfo {
 #[repr(C)]
 #[derive(Clone, Copy, Debug, Default, PartialEq, Pod, Zeroable)]
 pub struct TransferAccountInfo {
-    /// The available balance (encrypted by `encrypiton_pubkey`)
+    /// The available balance (encrypted by `encryption_pubkey`)
     pub available_balance: EncryptedBalance,
     /// The decryptable available balance
     pub decryptable_available_balance: DecryptableBalance,

token/program-2022/src/extension/confidential_transfer/mod.rs

@@ -90,7 +90,7 @@ pub struct ConfidentialTransferAccount {
     /// The high 48 bits of the pending balance (encrypted by `elgamal_pubkey`)
     pub pending_balance_hi: EncryptedBalance,
 
-    /// The available balance (encrypted by `encrypiton_pubkey`)
+    /// The available balance (encrypted by `encryption_pubkey`)
     pub available_balance: EncryptedBalance,
 
     /// The decryptable available balance