refactor: bundle private/public i/o into action struccts

integration_tests/tests/auth_transfer/private.rs

@@ -81,9 +81,9 @@ async fn private_transfer_to_foreign_account() -> Result<()> {
         .context("Failed to get private account commitment for sender")?;
 
     let tx = fetch_privacy_preserving_tx(ctx.sequencer_client(), tx_hash).await;
-    assert!(tx.message.new_commitments.contains(&new_commitment1));
+    assert!(tx.message.commitments().contains(&new_commitment1));
 
-    for commitment in tx.message.new_commitments {
+    for commitment in tx.message.commitments() {
         assert!(verify_commitment_is_in_state(commitment, ctx.sequencer_client()).await);
     }
 
@@ -169,9 +169,9 @@ async fn private_transfer_to_owned_account_using_claiming_path() -> Result<()> {
         .wallet()
         .get_private_account_commitment(from)
         .context("Failed to get private account commitment for sender")?;
-    assert!(tx.message.new_commitments.contains(&sender_commitment));
+    assert!(tx.message.commitments().contains(&sender_commitment));
 
-    for commitment in tx.message.new_commitments {
+    for commitment in tx.message.commitments() {
         assert!(verify_commitment_is_in_state(commitment, ctx.sequencer_client()).await);
     }
 
@@ -245,7 +245,7 @@ async fn shielded_transfer_to_foreign_account() -> Result<()> {
 
     let acc_1_balance = account_balance(&ctx, from).await?;
 
-    for commitment in tx.message.new_commitments {
+    for commitment in tx.message.commitments() {
         assert!(verify_commitment_is_in_state(commitment, ctx.sequencer_client()).await);
     }
 
@@ -301,7 +301,7 @@ async fn private_transfer_to_owned_account_continuous_run_path() -> Result<()> {
     tokio::time::sleep(Duration::from_secs(TIME_TO_WAIT_FOR_BLOCK_SECONDS)).await;
 
     // Verify commitments are in state
-    for commitment in tx.message.new_commitments {
+    for commitment in tx.message.commitments() {
         assert!(verify_commitment_is_in_state(commitment, ctx.sequencer_client()).await);
     }
 
@@ -657,8 +657,9 @@ async fn init_with_dummy_commitment_root_produces_valid_root() -> Result<()> {
 
     let output = prove_init_with_commitment_root(&ctx, expected_digest).await?;
 
-    assert_eq!(output.new_nullifiers.len(), 1);
-    let (nullifier, digest) = &output.new_nullifiers[0];
+    assert_eq!(output.private_actions.len(), 1);
+    let action = &output.private_actions[0];
+    let (nullifier, digest) = (&action.nullifier, &action.root);
     assert_eq!(
         *nullifier,
         Nullifier::for_account_initialization(&recipient_account_id)
@@ -678,14 +679,14 @@ async fn init_nullifier_digest_is_bound_to_commitment_root() -> Result<()> {
     let output_with_root = prove_init_with_commitment_root(&ctx, expected_digest).await?;
     let output_without_root = prove_init_with_commitment_root(&ctx, DUMMY_COMMITMENT_HASH).await?;
 
-    assert_eq!(output_with_root.new_nullifiers[0].1, expected_digest);
+    assert_eq!(output_with_root.private_actions[0].root, expected_digest);
     assert_eq!(
-        output_without_root.new_nullifiers[0].1,
+        output_without_root.private_actions[0].root,
         DUMMY_COMMITMENT_HASH
     );
     assert_ne!(
-        output_with_root.new_nullifiers[0].1,
-        output_without_root.new_nullifiers[0].1,
+        output_with_root.private_actions[0].root,
+        output_without_root.private_actions[0].root,
     );
 
     Ok(())

integration_tests/tests/bridge.rs

@@ -201,12 +201,10 @@ async fn private_bridge_deposit_invocation_is_dropped() -> anyhow::Result<()> {
     .context("Failed to execute/prove bridge deposit")?;
 
     // Create privacy-preserving transaction from circuit output
-    let message = privacy_preserving_transaction::Message::try_from_circuit_output(
-        vec![bridge_account_id, recipient_vault_id],
+    let message = privacy_preserving_transaction::Message::from_circuit_output(
         vec![bridge_pre.account.nonce, vault_pre.account.nonce],
         output,
-    )
-    .context("Failed to build privacy-preserving bridge deposit message")?;
+    );
 
     let witness_set = privacy_preserving_transaction::WitnessSet::for_message(&message, proof, &[]);
     let attack_tx = LeeTransaction::PrivacyPreserving(lee::PrivacyPreservingTransaction::new(

integration_tests/tests/keys.rs

@@ -71,9 +71,9 @@ async fn sync_private_account_with_non_zero_chain_index() -> Result<()> {
         .wallet()
         .get_private_account_commitment(from)
         .context("Failed to get private account commitment for sender")?;
-    assert!(tx.message.new_commitments.contains(&new_commitment1));
+    assert!(tx.message.commitments().contains(&new_commitment1));
 
-    for commitment in tx.message.new_commitments {
+    for commitment in tx.message.commitments() {
         assert!(verify_commitment_is_in_state(commitment, ctx.sequencer_client()).await);
     }
 

integration_tests/tests/private_pda.rs

@@ -83,9 +83,7 @@ async fn fund_private_pda(
     )
     .map_err(|e| anyhow::anyhow!("circuit proving failed: {e}"))?;
 
-    let message =
-        Message::try_from_circuit_output(vec![sender], vec![sender_account.nonce], output)
-            .map_err(|e| anyhow::anyhow!("message build failed: {e}"))?;
+    let message = Message::from_circuit_output(vec![sender_account.nonce], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[sender_sk]);
     let tx = PrivacyPreservingTransaction::new(message, witness_set);

integration_tests/tests/private_transaction_padding.rs

@@ -26,9 +26,7 @@ async fn private_transaction_pads_notes_to_max() -> Result<()> {
 
     let tx = fetch_privacy_preserving_tx(ctx.sequencer_client(), tx_hash).await;
 
-    assert_eq!(tx.message.new_commitments.len(), 7);
-    assert_eq!(tx.message.new_nullifiers.len(), 7);
-    assert_eq!(tx.message.encrypted_private_post_states.len(), 7);
+    assert_eq!(tx.message.private_actions.len(), 7);
 
     Ok(())
 }

integration_tests/tests/tps.rs

@@ -310,7 +310,7 @@ fn build_privacy_transaction() -> PrivacyPreservingTransaction {
         &program.into(),
     )
     .unwrap();
-    let message = pptx::message::Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+    let message = pptx::message::Message::from_circuit_output(vec![], output);
     let witness_set = pptx::witness_set::WitnessSet::for_message(&message, proof, &[]);
     pptx::PrivacyPreservingTransaction::new(message, witness_set)
 }

lee/privacy_preserving_circuit/src/output.rs

@@ -1,7 +1,8 @@
 use lee_core::{
     Commitment, CommitmentSetDigest, DummyInput, EncryptedAccountData, EncryptionScheme,
     EphemeralSecretKey, InputAccountIdentity, MembershipProof, Nullifier, NullifierPublicKey,
-    NullifierSecretKey, PrivacyPreservingCircuitOutput, PrivateAccountKind, SharedSecretKey,
+    NullifierSecretKey, PrivacyPreservingCircuitOutput, PrivateAccountKind, PrivateAction,
+    PublicAction, SharedSecretKey,
     account::{Account, AccountId, Nonce},
     compute_digest_for_path,
     encryption::{ViewTag, ViewingPublicKey},
@@ -17,11 +18,8 @@ pub fn compute_circuit_output(
     let (block_validity_window, timestamp_validity_window, pda_seed_by_position, states_iter) =
         execution_state.into_parts();
     let mut output = PrivacyPreservingCircuitOutput {
-        public_pre_states: Vec::new(),
-        public_post_states: Vec::new(),
-        encrypted_private_post_states: Vec::new(),
-        new_commitments: Vec::new(),
-        new_nullifiers: Vec::new(),
+        public_actions: Vec::new(),
+        private_actions: Vec::new(),
         block_validity_window,
         timestamp_validity_window,
     };
@@ -37,8 +35,10 @@ pub fn compute_circuit_output(
     {
         match account_identity {
             InputAccountIdentity::Public => {
-                output.public_pre_states.push(pre_state);
-                output.public_post_states.push(post_state);
+                output.public_actions.push(PublicAction {
+                    pre: pre_state,
+                    post: post_state,
+                });
             }
             InputAccountIdentity::PrivateAuthorizedInit {
                 vpk,
@@ -267,16 +267,20 @@ pub fn compute_circuit_output(
 }
 
 fn obfuscate_output_ordering(output: &mut PrivacyPreservingCircuitOutput) {
-    output
-        .new_commitments
-        .sort_unstable_by_key(Commitment::to_byte_array);
-
-    let mut notes: Vec<_> = core::mem::take(&mut output.new_nullifiers)
-        .into_iter()
-        .zip(core::mem::take(&mut output.encrypted_private_post_states))
+    let mut commitments: Vec<_> = output
+        .private_actions
+        .iter()
+        .map(|action| action.commitment.clone())
         .collect();
-    notes.sort_unstable_by_key(|((nullifier, _), _)| nullifier.to_byte_array());
-    (output.new_nullifiers, output.encrypted_private_post_states) = notes.into_iter().unzip();
+    commitments.sort_unstable_by_key(Commitment::to_byte_array);
+
+    output
+        .private_actions
+        .sort_unstable_by_key(|action| action.nullifier.to_byte_array());
+
+    for (action, commitment) in output.private_actions.iter_mut().zip(commitments) {
+        action.commitment = commitment;
+    }
 }
 
 fn emit_dummy_output(output: &mut PrivacyPreservingCircuitOutput, dummy: DummyInput) {
@@ -284,17 +288,18 @@ fn emit_dummy_output(output: &mut PrivacyPreservingCircuitOutput, dummy: DummyIn
     // The prover is responsible for their randomness.
     let nullifier = Nullifier::for_dummy(&dummy.nullifier_seed);
     let commitment = Commitment::for_dummy(&nullifier, &dummy.commitment_seed);
-    output
-        .new_nullifiers
-        .push((nullifier, dummy.commitment_root));
-    output.new_commitments.push(commitment);
     // Note: the encrypted post states are pushed as fed into the circuit.
     // That means that the prover is responsible for managing the randomness
     // so as to not reveal the padding.
     //
     // In particular, it is recommended to generate the ML KEM ciphertext
     // explicitly as these are not uniformly random.
-    output.encrypted_private_post_states.push(dummy.note);
+    output.private_actions.push(PrivateAction {
+        nullifier,
+        root: dummy.commitment_root,
+        commitment,
+        encrypted_post_state: dummy.note,
+    });
 }
 
 #[expect(
@@ -327,15 +332,16 @@ fn emit_private_output(
         &new_nullifier.0,
     );
 
-    output.new_nullifiers.push(new_nullifier);
-    output.new_commitments.push(commitment_post);
-    output
-        .encrypted_private_post_states
-        .push(EncryptedAccountData {
+    output.private_actions.push(PrivateAction {
+        nullifier: new_nullifier.0,
+        root: new_nullifier.1,
+        commitment: commitment_post,
+        encrypted_post_state: EncryptedAccountData {
             ciphertext: encrypted_account,
             epk,
             view_tag,
-        });
+        },
+    });
 }
 
 fn compute_update_nullifier_and_set_digest(
@@ -358,7 +364,7 @@ mod tests {
 
     use super::*;
 
-    fn note(tag: u8) -> (Nullifier, Commitment, EncryptedAccountData) {
+    fn note(tag: u8) -> PrivateAction {
         let nullifier = Nullifier::for_dummy(&[tag; 32]);
         let commitment = Commitment::for_dummy(&nullifier, &[tag; 32]);
         let ciphertext = EncryptionScheme::encrypt(
@@ -367,37 +373,36 @@ mod tests {
             &SharedSecretKey([0; 32]),
             &nullifier,
         );
-        let encrypted = EncryptedAccountData {
-            ciphertext,
-            epk: EphemeralPublicKey(vec![tag]),
-            view_tag: 0,
-        };
-        (nullifier, commitment, encrypted)
+        PrivateAction {
+            nullifier,
+            root: DUMMY_COMMITMENT_HASH,
+            commitment,
+            encrypted_post_state: EncryptedAccountData {
+                ciphertext,
+                epk: EphemeralPublicKey(vec![tag]),
+                view_tag: 0,
+            },
+        }
     }
 
     #[test]
     fn obfuscate_byte_sorts_commitments_and_nullifiers() {
         let mut output = PrivacyPreservingCircuitOutput::default();
         for tag in 0..3 {
-            let (nullifier, commitment, encrypted) = note(tag);
-            output
-                .new_nullifiers
-                .push((nullifier, DUMMY_COMMITMENT_HASH));
-            output.new_commitments.push(commitment);
-            output.encrypted_private_post_states.push(encrypted);
+            output.private_actions.push(note(tag));
         }
 
         obfuscate_output_ordering(&mut output);
 
         assert!(
             output
-                .new_commitments
-                .is_sorted_by_key(Commitment::to_byte_array)
+                .private_actions
+                .is_sorted_by_key(|action| action.nullifier.to_byte_array())
         );
         assert!(
             output
-                .new_nullifiers
-                .is_sorted_by_key(|(nullifier, _)| nullifier.to_byte_array())
+                .private_actions
+                .is_sorted_by_key(|action| action.commitment.to_byte_array())
         );
     }
 
@@ -405,27 +410,26 @@ mod tests {
     fn obfuscate_keeps_each_nullifier_with_its_ciphertext() {
         let mut output = PrivacyPreservingCircuitOutput::default();
         for tag in 0..3 {
-            let (nullifier, _, encrypted) = note(tag);
-            output
-                .new_nullifiers
-                .push((nullifier, DUMMY_COMMITMENT_HASH));
-            output.encrypted_private_post_states.push(encrypted);
+            output.private_actions.push(note(tag));
         }
         let paired: HashMap<[u8; 32], EphemeralPublicKey> = output
-            .new_nullifiers
+            .private_actions
             .iter()
-            .zip(&output.encrypted_private_post_states)
-            .map(|((nullifier, _), note)| (nullifier.to_byte_array(), note.epk.clone()))
+            .map(|action| {
+                (
+                    action.nullifier.to_byte_array(),
+                    action.encrypted_post_state.epk.clone(),
+                )
+            })
             .collect();
 
         obfuscate_output_ordering(&mut output);
 
-        for ((nullifier, _), note) in output
-            .new_nullifiers
-            .iter()
-            .zip(&output.encrypted_private_post_states)
-        {
-            assert_eq!(paired[&nullifier.to_byte_array()], note.epk);
+        for action in &output.private_actions {
+            assert_eq!(
+                paired[&action.nullifier.to_byte_array()],
+                action.encrypted_post_state.epk
+            );
         }
     }
 }

lee/state_machine/core/src/circuit_io.rs

@@ -1,3 +1,4 @@
+use borsh::{BorshDeserialize, BorshSerialize};
 use serde::{Deserialize, Serialize};
 
 use crate::{
@@ -147,18 +148,53 @@ impl InputAccountIdentity {
     }
 }
 
+#[derive(Serialize, Deserialize, BorshSerialize, BorshDeserialize)]
+#[cfg_attr(
+    any(feature = "host", test),
+    derive(Debug, Clone, Default, PartialEq, Eq)
+)]
+pub struct PrivateAction {
+    pub nullifier: Nullifier,
+    pub root: CommitmentSetDigest,
+    pub commitment: Commitment,
+    pub encrypted_post_state: EncryptedAccountData,
+}
+
+#[derive(Serialize, Deserialize)]
+#[cfg_attr(any(feature = "host", test), derive(Debug, PartialEq, Eq))]
+pub struct PublicAction {
+    pub pre: AccountWithMetadata,
+    pub post: Account,
+}
+
 #[derive(Serialize, Deserialize)]
 #[cfg_attr(any(feature = "host", test), derive(Debug, PartialEq, Eq, Default))]
 pub struct PrivacyPreservingCircuitOutput {
-    pub public_pre_states: Vec<AccountWithMetadata>,
-    pub public_post_states: Vec<Account>,
-    pub encrypted_private_post_states: Vec<EncryptedAccountData>,
-    pub new_commitments: Vec<Commitment>,
-    pub new_nullifiers: Vec<(Nullifier, CommitmentSetDigest)>,
+    pub public_actions: Vec<PublicAction>,
+    pub private_actions: Vec<PrivateAction>,
     pub block_validity_window: BlockValidityWindow,
     pub timestamp_validity_window: TimestampValidityWindow,
 }
 
+#[cfg(any(feature = "host", test))]
+impl PrivacyPreservingCircuitOutput {
+    #[must_use]
+    pub fn commitments(&self) -> Vec<Commitment> {
+        self.private_actions
+            .iter()
+            .map(|action| action.commitment.clone())
+            .collect()
+    }
+
+    #[must_use]
+    pub fn nullifiers(&self) -> Vec<(Nullifier, CommitmentSetDigest)> {
+        self.private_actions
+            .iter()
+            .map(|action| (action.nullifier, action.root))
+            .collect()
+    }
+}
+
 #[cfg(feature = "host")]
 impl PrivacyPreservingCircuitOutput {
     /// Serializes the circuit output to a byte vector.
@@ -183,50 +219,57 @@ mod tests {
     #[test]
     fn privacy_preserving_circuit_output_to_bytes_is_compatible_with_from_slice() {
         let output = PrivacyPreservingCircuitOutput {
-            public_pre_states: vec![
-                AccountWithMetadata::new(
-                    Account {
+            public_actions: vec![
+                PublicAction {
+                    pre: AccountWithMetadata::new(
+                        Account {
+                            program_owner: [1, 2, 3, 4, 5, 6, 7, 8],
+                            balance: 12_345_678_901_234_567_890,
+                            data: b"test data".to_vec().try_into().unwrap(),
+                            nonce: Nonce(0xFFFF_FFFF_FFFF_FFFE),
+                        },
+                        true,
+                        AccountId::new([0; 32]),
+                    ),
+                    post: Account {
                         program_owner: [1, 2, 3, 4, 5, 6, 7, 8],
-                        balance: 12_345_678_901_234_567_890,
-                        data: b"test data".to_vec().try_into().unwrap(),
-                        nonce: Nonce(0xFFFF_FFFF_FFFF_FFFE),
+                        balance: 100,
+                        data: b"post state data".to_vec().try_into().unwrap(),
+                        nonce: Nonce(0xFFFF_FFFF_FFFF_FFFF),
                     },
-                    true,
-                    AccountId::new([0; 32]),
-                ),
-                AccountWithMetadata::new(
-                    Account {
-                        program_owner: [9, 9, 9, 8, 8, 8, 7, 7],
-                        balance: 123_123_123_456_456_567_112,
-                        data: b"test data".to_vec().try_into().unwrap(),
-                        nonce: Nonce(9_999_999_999_999_999_999_999),
+                },
+                PublicAction {
+                    pre: AccountWithMetadata::new(
+                        Account {
+                            program_owner: [9, 9, 9, 8, 8, 8, 7, 7],
+                            balance: 123_123_123_456_456_567_112,
+                            data: b"test data".to_vec().try_into().unwrap(),
+                            nonce: Nonce(9_999_999_999_999_999_999_999),
+                        },
+                        false,
+                        AccountId::new([1; 32]),
+                    ),
+                    post: Account {
+                        program_owner: [2, 3, 4, 5, 6, 7, 8, 9],
+                        balance: 200,
+                        data: b"post state data 2".to_vec().try_into().unwrap(),
+                        nonce: Nonce(0xFFFF_FFFF_FFFF_FFFD),
                     },
-                    false,
-                    AccountId::new([1; 32]),
-                ),
+                },
             ],
-            public_post_states: vec![Account {
-                program_owner: [1, 2, 3, 4, 5, 6, 7, 8],
-                balance: 100,
-                data: b"post state data".to_vec().try_into().unwrap(),
-                nonce: Nonce(0xFFFF_FFFF_FFFF_FFFF),
-            }],
-            encrypted_private_post_states: vec![EncryptedAccountData {
-                ciphertext: Ciphertext(vec![255, 255, 1, 1, 2, 2]),
-                epk: EphemeralPublicKey(vec![9, 9, 9]),
-                view_tag: 42,
-            }],
-            new_commitments: vec![Commitment::new(
-                &AccountId::new([1; 32]),
-                &Account::default(),
-            )],
-            new_nullifiers: vec![(
-                Nullifier::for_account_update(
+            private_actions: vec![PrivateAction {
+                nullifier: Nullifier::for_account_update(
                     &Commitment::new(&AccountId::new([2; 32]), &Account::default()),
                     &[1; 32],
                 ),
-                [0xab; 32],
-            )],
+                root: [0xab; 32],
+                commitment: Commitment::new(&AccountId::new([1; 32]), &Account::default()),
+                encrypted_post_state: EncryptedAccountData {
+                    ciphertext: Ciphertext(vec![255, 255, 1, 1, 2, 2]),
+                    epk: EphemeralPublicKey(vec![9, 9, 9]),
+                    view_tag: 42,
+                },
+            }],
             block_validity_window: (1..).into(),
             timestamp_validity_window: TimestampValidityWindow::new_unbounded(),
         };

lee/state_machine/core/src/commitment.rs

@@ -32,10 +32,10 @@ pub const DUMMY_COMMITMENT_HASH: [u8; 32] = [
     129, 241, 118, 39, 41, 253, 141, 171, 184, 71, 8, 41,
 ];
 
-#[derive(Serialize, Deserialize, BorshSerialize, BorshDeserialize)]
+#[derive(Clone, Serialize, Deserialize, BorshSerialize, BorshDeserialize)]
 #[cfg_attr(
     any(feature = "host", test),
-    derive(Clone, PartialEq, Eq, Hash, PartialOrd, Ord)
+    derive(Default, PartialEq, Eq, Hash, PartialOrd, Ord)
 )]
 pub struct Commitment(pub(super) [u8; 32]);
 

lee/state_machine/core/src/encryption/mod.rs

@@ -45,13 +45,15 @@ pub struct SharedSecretKey(pub [u8; 32]);
 
 /// The ML-KEM-768 ciphertext produced during encapsulation; transmitted on-wire in place of the
 /// former ECDH ephemeral public key. Always `ML_KEM_768_CIPHERTEXT_LEN` (1088) bytes.
-#[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Eq, BorshSerialize, BorshDeserialize)]
+#[derive(
+    Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, BorshSerialize, BorshDeserialize,
+)]
 pub struct EphemeralPublicKey(pub Vec<u8>);
 
 pub struct EncryptionScheme;
 
 #[derive(Serialize, Deserialize, BorshSerialize, BorshDeserialize)]
-#[cfg_attr(any(feature = "host", test), derive(Clone, PartialEq, Eq))]
+#[cfg_attr(any(feature = "host", test), derive(Clone, Default, PartialEq, Eq))]
 pub struct Ciphertext(pub(crate) Vec<u8>);
 
 #[cfg(any(feature = "host", test))]
@@ -71,7 +73,10 @@ pub type ViewTag = u8;
 
 /// Encrypted private-account note for one output.
 #[derive(Serialize, Deserialize, BorshSerialize, BorshDeserialize)]
-#[cfg_attr(any(feature = "host", test), derive(Debug, Clone, PartialEq, Eq))]
+#[cfg_attr(
+    any(feature = "host", test),
+    derive(Debug, Clone, Default, PartialEq, Eq)
+)]
 pub struct EncryptedAccountData {
     pub ciphertext: Ciphertext,
     pub epk: EphemeralPublicKey,

lee/state_machine/core/src/lib.rs

@@ -4,7 +4,8 @@
 )]
 
 pub use circuit_io::{
-    DummyInput, InputAccountIdentity, PrivacyPreservingCircuitInput, PrivacyPreservingCircuitOutput,
+    DummyInput, InputAccountIdentity, PrivacyPreservingCircuitInput,
+    PrivacyPreservingCircuitOutput, PrivateAction, PublicAction,
 };
 pub use commitment::{
     Commitment, CommitmentSetDigest, DUMMY_COMMITMENT, DUMMY_COMMITMENT_HASH, MembershipProof,

lee/state_machine/core/src/nullifier.rs

@@ -72,7 +72,7 @@ pub type NullifierSecretKey = [u8; 32];
 #[derive(Serialize, Deserialize, BorshSerialize, BorshDeserialize)]
 #[cfg_attr(
     any(feature = "host", test),
-    derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)
+    derive(Clone, Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash)
 )]
 pub struct Nullifier(pub(super) [u8; 32]);
 

lee/state_machine/src/privacy_preserving_transaction/circuit/tests.rs

@@ -24,9 +24,9 @@ fn decrypt_kind(
     idx: usize,
 ) -> PrivateAccountKind {
     let (kind, _) = EncryptionScheme::decrypt(
-        &output.encrypted_private_post_states[idx].ciphertext,
+        &output.private_actions[idx].encrypted_post_state.ciphertext,
         ssk,
-        &output.new_nullifiers[idx].0,
+        &output.private_actions[idx].nullifier,
     )
     .unwrap();
     kind
@@ -102,18 +102,16 @@ fn prove_privacy_preserving_execution_circuit_public_and_private_pre_accounts()
 
     assert!(proof.is_valid_for(&output));
 
-    let [sender_pre] = output.public_pre_states.try_into().unwrap();
-    let [sender_post] = output.public_post_states.try_into().unwrap();
+    let [action] = output.public_actions.try_into().unwrap();
+    let (sender_pre, sender_post) = (action.pre, action.post);
     assert_eq!(sender_pre, expected_sender_pre);
     assert_eq!(sender_post, expected_sender_post);
-    assert_eq!(output.new_commitments.len(), 1);
-    assert_eq!(output.new_nullifiers.len(), 1);
-    assert_eq!(output.encrypted_private_post_states.len(), 1);
+    assert_eq!(output.private_actions.len(), 1);
 
     let (_identifier, recipient_post) = EncryptionScheme::decrypt(
-        &output.encrypted_private_post_states[0].ciphertext,
+        &output.private_actions[0].encrypted_post_state.ciphertext,
         &shared_secret,
-        &output.new_nullifiers[0].0,
+        &output.private_actions[0].nullifier,
     )
     .unwrap();
     assert_eq!(recipient_post, expected_recipient_post);
@@ -216,43 +214,46 @@ fn prove_privacy_preserving_execution_circuit_fully_private() {
     .unwrap();
 
     assert!(proof.is_valid_for(&output));
-    assert!(output.public_pre_states.is_empty());
-    assert!(output.public_post_states.is_empty());
+    assert!(output.public_actions.is_empty());
     let sender_nullifier = expected_new_nullifiers[0].0;
     let recipient_nullifier = expected_new_nullifiers[1].0;
 
-    let mut expected_new_commitments = expected_new_commitments;
-    expected_new_commitments.sort_unstable_by_key(Commitment::to_byte_array);
-    assert_eq!(output.new_commitments, expected_new_commitments);
+    let mut sorted_commitments = expected_new_commitments;
+    sorted_commitments.sort_unstable_by_key(Commitment::to_byte_array);
+    assert_eq!(output.commitments(), sorted_commitments);
 
-    let mut expected_new_nullifiers = expected_new_nullifiers;
-    expected_new_nullifiers.sort_unstable_by_key(|(nullifier, _)| nullifier.to_byte_array());
-    assert_eq!(output.new_nullifiers, expected_new_nullifiers);
+    let mut sorted_nullifiers = expected_new_nullifiers;
+    sorted_nullifiers.sort_unstable_by_key(|(nullifier, _)| nullifier.to_byte_array());
+    assert_eq!(output.nullifiers(), sorted_nullifiers);
 
-    assert_eq!(output.encrypted_private_post_states.len(), 2);
+    assert_eq!(output.private_actions.len(), 2);
 
     let sender_slot = output
-        .new_nullifiers
+        .private_actions
         .iter()
-        .position(|(nullifier, _)| *nullifier == sender_nullifier)
+        .position(|action| action.nullifier == sender_nullifier)
         .unwrap();
     let (_identifier, sender_post) = EncryptionScheme::decrypt(
-        &output.encrypted_private_post_states[sender_slot].ciphertext,
+        &output.private_actions[sender_slot]
+            .encrypted_post_state
+            .ciphertext,
         &shared_secret_1,
-        &output.new_nullifiers[sender_slot].0,
+        &output.private_actions[sender_slot].nullifier,
     )
     .unwrap();
     assert_eq!(sender_post, expected_private_account_1);
 
     let recipient_slot = output
-        .new_nullifiers
+        .private_actions
         .iter()
-        .position(|(nullifier, _)| *nullifier == recipient_nullifier)
+        .position(|action| action.nullifier == recipient_nullifier)
         .unwrap();
     let (_identifier, recipient_post) = EncryptionScheme::decrypt(
-        &output.encrypted_private_post_states[recipient_slot].ciphertext,
+        &output.private_actions[recipient_slot]
+            .encrypted_post_state
+            .ciphertext,
         &shared_secret_2,
-        &output.new_nullifiers[recipient_slot].0,
+        &output.private_actions[recipient_slot].nullifier,
     )
     .unwrap();
     assert_eq!(recipient_post, expected_private_account_2);
@@ -281,9 +282,9 @@ fn init_note_view_tag_is_derived_from_account_keys() {
     .unwrap();
 
     assert!(proof.is_valid_for(&output));
-    assert_eq!(output.encrypted_private_post_states.len(), 1);
+    assert_eq!(output.private_actions.len(), 1);
     assert_eq!(
-        output.encrypted_private_post_states[0].view_tag,
+        output.private_actions[0].encrypted_post_state.view_tag,
         EncryptedAccountData::compute_view_tag(&keys.npk(), &keys.vpk()),
     );
 }
@@ -324,8 +325,11 @@ fn update_note_view_tag_is_the_supplied_value() {
     .unwrap();
 
     assert!(proof.is_valid_for(&output));
-    assert_eq!(output.encrypted_private_post_states.len(), 1);
-    assert_eq!(output.encrypted_private_post_states[0].view_tag, fed_tag);
+    assert_eq!(output.private_actions.len(), 1);
+    assert_eq!(
+        output.private_actions[0].encrypted_post_state.view_tag,
+        fed_tag
+    );
 }
 
 #[test]
@@ -448,7 +452,7 @@ fn private_pda_init() {
     );
 
     let (output, _proof) = result.expect("PDA init should succeed");
-    assert_eq!(output.new_commitments.len(), 1);
+    assert_eq!(output.private_actions.len(), 1);
 }
 
 /// PDA withdraw: chains to `simple_balance_transfer` to move balance from PDA to recipient.
@@ -502,7 +506,7 @@ fn private_pda_withdraw() {
     );
 
     let (output, _proof) = result.expect("PDA withdraw should succeed");
-    assert_eq!(output.new_commitments.len(), 1);
+    assert_eq!(output.private_actions.len(), 1);
 }
 
 /// Shared regular private account: receives funds via `authenticated_transfer` directly,
@@ -554,7 +558,7 @@ fn shared_account_receives_via_simple_transfer() {
 
     let (output, _proof) = result.expect("shared account receive should succeed");
     // Sender is public (no commitment), recipient is private (1 commitment)
-    assert_eq!(output.new_commitments.len(), 1);
+    assert_eq!(output.private_actions.len(), 1);
 }
 
 /// `PrivateAuthorizedInit` with a non-default identifier produces a ciphertext that decrypts

lee/state_machine/src/privacy_preserving_transaction/message.rs

@@ -1,24 +1,27 @@
 use borsh::{BorshDeserialize, BorshSerialize};
 use lee_core::{
-    Commitment, CommitmentSetDigest, Nullifier, PrivacyPreservingCircuitOutput,
+    Commitment, CommitmentSetDigest, Nullifier, PrivacyPreservingCircuitOutput, PrivateAction,
     account::{Account, Nonce},
     program::{BlockValidityWindow, TimestampValidityWindow},
 };
 pub use lee_core::{EncryptedAccountData, ViewTag};
 use sha2::{Digest as _, Sha256};
 
-use crate::{AccountId, error::LeeError};
+use crate::AccountId;
 
 const PREFIX: &[u8; 32] = b"/LEE/v0.3/Message/Privacy/\x00\x00\x00\x00\x00\x00";
 
+#[derive(Debug, Clone, PartialEq, Eq, BorshSerialize, BorshDeserialize)]
+pub struct PublicActionWithID {
+    pub account_id: AccountId,
+    pub post_state: Account,
+}
+
 #[derive(Clone, Default, PartialEq, Eq, BorshSerialize, BorshDeserialize)]
 pub struct Message {
-    pub public_account_ids: Vec<AccountId>,
+    pub public_actions: Vec<PublicActionWithID>,
     pub nonces: Vec<Nonce>,
-    pub public_post_states: Vec<Account>,
-    pub encrypted_private_post_states: Vec<EncryptedAccountData>,
-    pub new_commitments: Vec<Commitment>,
-    pub new_nullifiers: Vec<(Nullifier, CommitmentSetDigest)>,
+    pub private_actions: Vec<PrivateAction>,
     pub block_validity_window: BlockValidityWindow,
     pub timestamp_validity_window: TimestampValidityWindow,
 }
@@ -31,21 +34,22 @@ impl std::fmt::Debug for Message {
                 write!(f, "{}", hex::encode(self.0))
             }
         }
-        let nullifiers: Vec<_> = self
-            .new_nullifiers
+        let private_actions: Vec<_> = self
+            .private_actions
             .iter()
-            .map(|(n, d)| (n, HexDigest(d)))
+            .map(|a| {
+                (
+                    &a.nullifier,
+                    HexDigest(&a.root),
+                    &a.commitment,
+                    &a.encrypted_post_state,
+                )
+            })
             .collect();
         f.debug_struct("Message")
-            .field("public_account_ids", &self.public_account_ids)
+            .field("public_actions", &self.public_actions)
             .field("nonces", &self.nonces)
-            .field("public_post_states", &self.public_post_states)
-            .field(
-                "encrypted_private_post_states",
-                &self.encrypted_private_post_states,
-            )
-            .field("new_commitments", &self.new_commitments)
-            .field("new_nullifiers", &nullifiers)
+            .field("private_actions", &private_actions)
             .field("block_validity_window", &self.block_validity_window)
             .field("timestamp_validity_window", &self.timestamp_validity_window)
             .finish()
@@ -53,21 +57,55 @@ impl std::fmt::Debug for Message {
 }
 
 impl Message {
-    pub fn try_from_circuit_output(
-        public_account_ids: Vec<AccountId>,
-        nonces: Vec<Nonce>,
-        output: PrivacyPreservingCircuitOutput,
-    ) -> Result<Self, LeeError> {
-        Ok(Self {
-            public_account_ids,
+    #[must_use]
+    pub fn from_circuit_output(nonces: Vec<Nonce>, output: PrivacyPreservingCircuitOutput) -> Self {
+        let public_actions = output
+            .public_actions
+            .into_iter()
+            .map(|action| PublicActionWithID {
+                account_id: action.pre.account_id,
+                post_state: action.post,
+            })
+            .collect();
+        Self {
+            public_actions,
             nonces,
-            public_post_states: output.public_post_states,
-            encrypted_private_post_states: output.encrypted_private_post_states,
-            new_commitments: output.new_commitments,
-            new_nullifiers: output.new_nullifiers,
+            private_actions: output.private_actions,
             block_validity_window: output.block_validity_window,
             timestamp_validity_window: output.timestamp_validity_window,
-        })
+        }
+    }
+
+    #[must_use]
+    pub fn commitments(&self) -> Vec<Commitment> {
+        self.private_actions
+            .iter()
+            .map(|action| action.commitment.clone())
+            .collect()
+    }
+
+    #[must_use]
+    pub fn nullifiers(&self) -> Vec<(Nullifier, CommitmentSetDigest)> {
+        self.private_actions
+            .iter()
+            .map(|action| (action.nullifier, action.root))
+            .collect()
+    }
+
+    #[must_use]
+    pub fn public_account_ids(&self) -> Vec<AccountId> {
+        self.public_actions
+            .iter()
+            .map(|action| action.account_id)
+            .collect()
+    }
+
+    #[must_use]
+    pub fn public_post_states(&self) -> Vec<Account> {
+        self.public_actions
+            .iter()
+            .map(|action| action.post_state.clone())
+            .collect()
     }
 
     #[must_use]
@@ -84,34 +122,20 @@ impl Message {
 
         Sha256::digest(bytes).into()
     }
-
-    /// Ensure that the commitments, nullifiers, and ciphertexts agree.
-    pub fn validate_note_lengths(&self) -> Result<usize, LeeError> {
-        let count = self.new_nullifiers.len();
-        if self.new_commitments.len() != count || self.encrypted_private_post_states.len() != count
-        {
-            return Err(LeeError::InvalidInput(format!(
-                "Note vectors disagree in length with {count} nullifiers, {} commitments, and {} ciphertexts",
-                self.new_commitments.len(),
-                self.encrypted_private_post_states.len(),
-            )));
-        }
-        Ok(count)
-    }
 }
 
 #[cfg(test)]
 pub mod tests {
     use lee_core::{
-        Commitment, EncryptionScheme, EphemeralSecretKey, Nullifier, NullifierPublicKey,
-        PrivateAccountKind, SharedSecretKey,
+        Commitment, EncryptionScheme, EphemeralPublicKey, EphemeralSecretKey, Nullifier,
+        NullifierPublicKey, PrivateAccountKind, PrivateAction, SharedSecretKey,
         account::{Account, AccountId, Nonce},
-        encryption::ViewingPublicKey,
+        encryption::{Ciphertext, ViewingPublicKey},
         program::{BlockValidityWindow, TimestampValidityWindow},
     };
     use sha2::{Digest as _, Sha256};
 
-    use super::{EncryptedAccountData, Message, PREFIX};
+    use super::{EncryptedAccountData, Message, PREFIX, PublicActionWithID};
 
     #[must_use]
     pub fn message_for_tests() -> Message {
@@ -125,78 +149,57 @@ pub mod tests {
         let npk2 = NullifierPublicKey::from(&nsk2);
         let vpk = ViewingPublicKey::from_seed(&[7; 32], &[8; 32]);
 
-        let public_account_ids = vec![AccountId::new([1; 32])];
-
         let nonces = vec![1_u128.into(), 2_u128.into(), 3_u128.into()];
 
-        let public_post_states = vec![Account::default()];
-
-        let encrypted_private_post_states = Vec::new();
-
         let account_id2 = lee_core::account::AccountId::for_regular_private_account(&npk2, &vpk, 0);
-        let new_commitments = vec![Commitment::new(&account_id2, &account2)];
+        let commitment = Commitment::new(&account_id2, &account2);
 
         let account_id1 = lee_core::account::AccountId::for_regular_private_account(&npk1, &vpk, 0);
         let old_commitment = Commitment::new(&account_id1, &account1);
-        let new_nullifiers = vec![(
-            Nullifier::for_account_update(&old_commitment, &nsk1),
-            [0; 32],
-        )];
+        let nullifier = Nullifier::for_account_update(&old_commitment, &nsk1);
 
         Message {
-            public_account_ids,
+            public_actions: vec![PublicActionWithID {
+                account_id: AccountId::new([1; 32]),
+                post_state: Account::default(),
+            }],
             nonces,
-            public_post_states,
-            encrypted_private_post_states,
-            new_commitments,
-            new_nullifiers,
+            private_actions: vec![PrivateAction {
+                nullifier,
+                root: [0; 32],
+                commitment,
+                encrypted_post_state: EncryptedAccountData {
+                    ciphertext: Ciphertext::from_inner(vec![]),
+                    epk: EphemeralPublicKey(vec![]),
+                    view_tag: 0,
+                },
+            }],
             block_validity_window: BlockValidityWindow::new_unbounded(),
             timestamp_validity_window: TimestampValidityWindow::new_unbounded(),
         }
     }
 
-    #[test]
-    fn validate_note_lengths_accepts_matching_and_rejects_mismatched() {
-        assert_eq!(Message::default().validate_note_lengths().unwrap(), 0);
-
-        let mismatched = Message {
-            new_commitments: vec![Commitment::new(
-                &AccountId::new([0; 32]),
-                &Account::default(),
-            )],
-            ..Default::default()
-        };
-        assert!(mismatched.validate_note_lengths().is_err());
-    }
-
     #[test]
     fn hash_privacy_pinned() {
         let msg = Message {
-            public_account_ids: vec![AccountId::new([42_u8; 32])],
+            public_actions: vec![],
             nonces: vec![Nonce(5)],
-            public_post_states: vec![],
-            encrypted_private_post_states: vec![],
-            new_commitments: vec![],
-            new_nullifiers: vec![],
+            private_actions: vec![],
             block_validity_window: BlockValidityWindow::new_unbounded(),
             timestamp_validity_window: TimestampValidityWindow::new_unbounded(),
         };
 
-        let public_account_ids_bytes: &[u8] = &[42_u8; 32];
+        // empty vec fields: u32 len=0
+        let public_actions_bytes: &[u8] = &[0, 0, 0, 0];
         let nonces_bytes: &[u8] = &[1, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
-        // all remaining vec fields are empty: u32 len=0
-        let empty_vec_bytes: &[u8] = &[0_u8; 4];
+        let private_actions_bytes: &[u8] = &[0, 0, 0, 0];
         // validity windows: unbounded = {from: None (0_u8), to: None (0_u8)}
-        let unbounded_window_bytes: &[u8] = &[0_u8; 2];
+        let unbounded_window_bytes: &[u8] = &[0, 0];
 
         let expected_borsh_vec: Vec<u8> = [
-            &[1_u8, 0, 0, 0], // public_account_ids
-            public_account_ids_bytes,
+            public_actions_bytes,
             nonces_bytes,
-            empty_vec_bytes,        // public_post_state
-            empty_vec_bytes,        // encrypted_private_post_states
-            empty_vec_bytes,        // new_commitments
-            empty_vec_bytes,        // new_nullifiers
+            private_actions_bytes,
             unbounded_window_bytes, // block_validity_window
             unbounded_window_bytes, // timestamp_validity_window
         ]

lee/state_machine/src/privacy_preserving_transaction/transaction.rs

@@ -53,7 +53,12 @@ impl PrivacyPreservingTransaction {
             .signer_account_ids()
             .into_iter()
             .collect::<HashSet<_>>();
-        acc_set.extend(&self.message.public_account_ids);
+        acc_set.extend(
+            self.message
+                .public_actions
+                .iter()
+                .map(|action| action.account_id),
+        );
 
         acc_set.into_iter().collect()
     }

lee/state_machine/src/state/tests/circuit.rs

@@ -402,11 +402,8 @@ fn private_pda_claim_succeeds() {
     );
 
     let (output, _proof) = result.expect("private PDA claim should succeed");
-    assert_eq!(output.new_nullifiers.len(), 1);
-    assert_eq!(output.new_commitments.len(), 1);
-    assert_eq!(output.encrypted_private_post_states.len(), 1);
-    assert!(output.public_pre_states.is_empty());
-    assert!(output.public_post_states.is_empty());
+    assert_eq!(output.private_actions.len(), 1);
+    assert!(output.public_actions.is_empty());
 }
 
 /// An npk is supplied that does not match the `pre_state`'s `account_id` under
@@ -482,8 +479,7 @@ fn caller_pda_seeds_authorize_private_pda_for_callee() {
 
     let (output, _proof) =
         result.expect("caller-seeds authorization of private PDA should succeed");
-    assert_eq!(output.new_commitments.len(), 1);
-    assert_eq!(output.new_nullifiers.len(), 1);
+    assert_eq!(output.private_actions.len(), 1);
 }
 
 /// The delegator chains with a different seed than the one it claimed with. In the callee
@@ -756,7 +752,7 @@ fn private_authorized_uninitialized_account() {
     .unwrap();
 
     // Create message from circuit output
-    let message = Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+    let message = Message::from_circuit_output(vec![], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[]);
 
@@ -801,7 +797,7 @@ fn private_unauthorized_uninitialized_account_can_still_be_claimed() {
     )
     .unwrap();
 
-    let message = Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+    let message = Message::from_circuit_output(vec![], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[]);
     let tx = PrivacyPreservingTransaction::new(message, witness_set);
@@ -851,7 +847,7 @@ fn private_account_claimed_then_used_without_init_flag_should_fail() {
     )
     .unwrap();
 
-    let message = Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+    let message = Message::from_circuit_output(vec![], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[]);
     let tx = PrivacyPreservingTransaction::new(message, witness_set);
@@ -961,8 +957,7 @@ fn two_private_pda_family_members_receive_and_spend() {
             &simple_transfer.clone().into(),
         )
         .unwrap();
-        let message =
-            Message::try_from_circuit_output(vec![funder_id], vec![funder_nonce], output).unwrap();
+        let message = Message::from_circuit_output(vec![funder_nonce], output);
         let witness_set = WitnessSet::for_message(&message, proof, &[&funder_keys.signing_key]);
         state
             .transition_from_privacy_preserving_transaction(
@@ -997,8 +992,7 @@ fn two_private_pda_family_members_receive_and_spend() {
             &simple_transfer.into(),
         )
         .unwrap();
-        let message =
-            Message::try_from_circuit_output(vec![funder_id], vec![funder_nonce], output).unwrap();
+        let message = Message::from_circuit_output(vec![funder_nonce], output);
         let witness_set = WitnessSet::for_message(&message, proof, &[&funder_keys.signing_key]);
         state
             .transition_from_privacy_preserving_transaction(
@@ -1041,8 +1035,7 @@ fn two_private_pda_family_members_receive_and_spend() {
             &spend_with_deps,
         )
         .unwrap();
-        let message =
-            Message::try_from_circuit_output(vec![recipient_id], vec![Nonce(0)], output).unwrap();
+        let message = Message::from_circuit_output(vec![Nonce(0)], output);
         let witness_set = WitnessSet::for_message(&message, proof, &[&recipient_signing_key]);
         state
             .transition_from_privacy_preserving_transaction(
@@ -1079,7 +1072,7 @@ fn two_private_pda_family_members_receive_and_spend() {
             &spend_with_deps,
         )
         .unwrap();
-        let message = Message::try_from_circuit_output(vec![recipient_id], vec![], output).unwrap();
+        let message = Message::from_circuit_output(vec![], output);
         let witness_set = WitnessSet::for_message(&message, proof, &[]);
         state
             .transition_from_privacy_preserving_transaction(
@@ -1130,9 +1123,7 @@ fn two_private_pda_family_members_receive_and_spend() {
             &crate::test_methods::simple_balance_transfer().into(),
         )
         .unwrap();
-        let message =
-            Message::try_from_circuit_output(vec![recipient_id], vec![recipient_nonce], output)
-                .unwrap();
+        let message = Message::from_circuit_output(vec![recipient_nonce], output);
         let witness_set = WitnessSet::for_message(&message, proof, &[&recipient_signing_key]);
         state
             .transition_from_privacy_preserving_transaction(

lee/state_machine/src/state/tests/claiming.rs

@@ -341,9 +341,7 @@ fn authorized_public_account_claiming_succeeds_when_executed_privately() {
     )
     .unwrap();
 
-    let message =
-        Message::try_from_circuit_output(vec![recipient_account_id], vec![Nonce(0)], output)
-            .unwrap();
+    let message = Message::from_circuit_output(vec![Nonce(0)], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[&recipient_private_key]);
     let tx = PrivacyPreservingTransaction::new(message, witness_set);
@@ -466,7 +464,7 @@ fn private_chained_call(number_of_calls: u32) {
     )
     .unwrap();
 
-    let message = Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+    let message = Message::from_circuit_output(vec![], output);
     let witness_set = WitnessSet::for_message(&message, proof, &[]);
     let transaction = PrivacyPreservingTransaction::new(message, witness_set);
 

lee/state_machine/src/state/tests/mod.rs

@@ -290,12 +290,7 @@ fn shielded_balance_transfer_for_tests(
     )
     .unwrap();
 
-    let message = Message::try_from_circuit_output(
-        vec![sender_keys.account_id()],
-        vec![sender_nonce],
-        output,
-    )
-    .unwrap();
+    let message = Message::from_circuit_output(vec![sender_nonce], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[&sender_keys.signing_key]);
     PrivacyPreservingTransaction::new(message, witness_set)
@@ -349,7 +344,7 @@ fn private_balance_transfer_for_tests(
     )
     .unwrap();
 
-    let message = Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+    let message = Message::from_circuit_output(vec![], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[]);
 
@@ -398,8 +393,7 @@ fn deshielded_balance_transfer_for_tests(
     )
     .unwrap();
 
-    let message =
-        Message::try_from_circuit_output(vec![*recipient_account_id], vec![], output).unwrap();
+    let message = Message::from_circuit_output(vec![], output);
 
     let witness_set = WitnessSet::for_message(&message, proof, &[]);
 

lee/state_machine/src/state/tests/privacy_preserving.rs

@@ -26,7 +26,7 @@ fn transition_from_privacy_preserving_transaction_shielded() {
         this
     };
 
-    let [expected_new_commitment] = tx.message().new_commitments.clone().try_into().unwrap();
+    let [expected_new_commitment] = tx.message().commitments().try_into().unwrap();
     assert!(!state.private_state.0.contains(&expected_new_commitment));
 
     state
@@ -128,7 +128,7 @@ fn privacy_tampered_epk_is_rejected() {
     );
 
     // Flip a byte of the first note's epk
-    tx.message.encrypted_private_post_states[0].epk.0[0] ^= 0xFF;
+    tx.message.private_actions[0].encrypted_post_state.epk.0[0] ^= 0xFF;
 
     assert!(
         matches!(
@@ -154,7 +154,7 @@ fn privacy_tampered_view_tag_is_rejected() {
     );
 
     // Flip the first note's view_tag
-    tx.message.encrypted_private_post_states[0].view_tag ^= 0xFF;
+    tx.message.private_actions[0].encrypted_post_state.view_tag ^= 0xFF;
 
     assert!(
         matches!(

lee/state_machine/src/state/tests/validity_window.rs

@@ -149,7 +149,7 @@ fn validity_window_works_in_privacy_preserving_transactions(
         )
         .unwrap();
 
-        let message = Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+        let message = Message::from_circuit_output(vec![], output);
 
         let witness_set = WitnessSet::for_message(&message, proof, &[]);
         PrivacyPreservingTransaction::new(message, witness_set)
@@ -214,7 +214,7 @@ fn timestamp_validity_window_works_in_privacy_preserving_transactions(
         )
         .unwrap();
 
-        let message = Message::try_from_circuit_output(vec![], vec![], output).unwrap();
+        let message = Message::from_circuit_output(vec![], output);
 
         let witness_set = WitnessSet::for_message(&message, proof, &[]);
         PrivacyPreservingTransaction::new(message, witness_set)

lee/state_machine/src/validated_state_diff/mod.rs

@@ -4,7 +4,7 @@ use std::{
 };
 
 use lee_core::{
-    BlockId, Commitment, Nullifier, PrivacyPreservingCircuitOutput, Timestamp,
+    BlockId, Commitment, Nullifier, PrivacyPreservingCircuitOutput, PublicAction, Timestamp,
     account::{Account, AccountId, AccountWithMetadata},
     program::{
         ChainedCall, Claim, DEFAULT_PROGRAM_ID, ProgramId, compute_public_authorized_pdas,
@@ -310,10 +310,13 @@ impl ValidatedStateDiff {
     ) -> Result<Self, LeeError> {
         let message = &tx.message;
         let witness_set = &tx.witness_set;
+        let commitments = message.commitments();
+        let nullifiers = message.nullifiers();
+        let public_account_ids = message.public_account_ids();
 
         // 1. Commitments or nullifiers are non empty
         ensure!(
-            !message.new_commitments.is_empty() || !message.new_nullifiers.is_empty(),
+            !message.private_actions.is_empty(),
             LeeError::InvalidInput(
                 "Empty commitments and empty nullifiers found in message".into(),
             )
@@ -321,25 +324,19 @@ impl ValidatedStateDiff {
 
         // 2. Check there are no duplicate account_ids in the public_account_ids list.
         ensure!(
-            n_unique(&message.public_account_ids) == message.public_account_ids.len(),
+            n_unique(&public_account_ids) == public_account_ids.len(),
             LeeError::InvalidInput("Duplicate account_ids found in message".into())
         );
 
         // Check there are no duplicate nullifiers in the new_nullifiers list
         ensure!(
-            n_unique(
-                &message
-                    .new_nullifiers
-                    .iter()
-                    .map(|(n, _)| n)
-                    .collect::<Vec<_>>()
-            ) == message.new_nullifiers.len(),
+            n_unique(&nullifiers.iter().map(|(n, _)| n).collect::<Vec<_>>()) == nullifiers.len(),
             LeeError::InvalidInput("Duplicate nullifiers found in message".into())
         );
 
         // Check there are no duplicate commitments in the new_commitments list
         ensure!(
-            n_unique(&message.new_commitments) == message.new_commitments.len(),
+            n_unique(&commitments) == commitments.len(),
             LeeError::InvalidInput("Duplicate commitments found in message".into())
         );
 
@@ -376,8 +373,7 @@ impl ValidatedStateDiff {
         );
 
         // Build pre_states for proof verification
-        let public_pre_states: Vec<_> = message
-            .public_account_ids
+        let public_pre_states: Vec<_> = public_account_ids
             .iter()
             .map(|account_id| {
                 AccountWithMetadata::new(
@@ -396,28 +392,22 @@ impl ValidatedStateDiff {
         )?;
 
         // 5. Commitment freshness
-        state.check_commitments_are_new(&message.new_commitments)?;
+        state.check_commitments_are_new(&commitments)?;
 
         // 6. Nullifier uniqueness
-        state.check_nullifiers_are_valid(&message.new_nullifiers)?;
+        state.check_nullifiers_are_valid(&nullifiers)?;
 
-        let public_diff = message
-            .public_account_ids
+        let public_diff = public_account_ids
             .iter()
             .copied()
-            .zip(message.public_post_states.clone())
-            .collect();
-        let new_nullifiers = message
-            .new_nullifiers
-            .iter()
-            .copied()
-            .map(|(nullifier, _)| nullifier)
+            .zip(message.public_post_states())
             .collect();
+        let new_nullifiers = nullifiers.iter().map(|(nullifier, _)| *nullifier).collect();
 
         Ok(Self(StateDiff {
             signer_account_ids,
             public_diff,
-            new_commitments: message.new_commitments.clone(),
+            new_commitments: commitments,
             new_nullifiers,
             program: None,
         }))
@@ -498,11 +488,13 @@ fn check_privacy_preserving_circuit_proof_is_valid(
     message: &Message,
 ) -> Result<(), LeeError> {
     let output = PrivacyPreservingCircuitOutput {
-        public_pre_states: public_pre_states.to_vec(),
-        public_post_states: message.public_post_states.clone(),
-        encrypted_private_post_states: message.encrypted_private_post_states.clone(),
-        new_commitments: message.new_commitments.clone(),
-        new_nullifiers: message.new_nullifiers.clone(),
+        public_actions: public_pre_states
+            .iter()
+            .cloned()
+            .zip(message.public_post_states())
+            .map(|(pre, post)| PublicAction { pre, post })
+            .collect(),
+        private_actions: message.private_actions.clone(),
         block_validity_window: message.block_validity_window,
         timestamp_validity_window: message.timestamp_validity_window,
     };

lee/state_machine/src/validated_state_diff/tests.rs

@@ -188,12 +188,10 @@ fn privacy_malicious_programs_cannot_drain_public_victim() {
 
     // public_account_ids lists the Public entries from account_identities, in order.
     // The single ciphertext belongs to attacker's private account update.
-    let message = Message::try_from_circuit_output(
-        vec![victim_id, recipient_id],
+    let message = Message::from_circuit_output(
         vec![], // no public signers, no nonces
         circuit_output,
-    )
-    .unwrap();
+    );
 
     let witness_set = WitnessSet::for_message(&message, proof, &[]); // no signatures
     let tx = PrivacyPreservingTransaction::new(message, witness_set);
@@ -350,12 +348,10 @@ fn privacy_malicious_programs_cannot_drain_private_victim() {
 
     // public_account_ids lists the Public entries from account_identities, in order.
     // The single ciphertext belongs to attacker's private account update.
-    let message = Message::try_from_circuit_output(
-        vec![victim_id, recipient_id],
+    let message = Message::from_circuit_output(
         vec![], // no public signers, no nonces
         circuit_output,
-    )
-    .unwrap();
+    );
 
     let witness_set = WitnessSet::for_message(&message, proof, &[]); // no signatures
     let tx = PrivacyPreservingTransaction::new(message, witness_set);
@@ -480,8 +476,9 @@ fn malicious_programs_cannot_drain_victim_without_signature() {
 #[test]
 fn privacy_garbage_proof_is_rejected() {
     use lee_core::{
-        Commitment,
+        Commitment, EncryptedAccountData, Nullifier, PrivateAction,
         account::Account,
+        encryption::{Ciphertext, EphemeralPublicKey},
         program::{BlockValidityWindow, TimestampValidityWindow},
     };
 
@@ -503,12 +500,18 @@ fn privacy_garbage_proof_is_rejected() {
     ));
     let commitment = Commitment::new(&account_id, &Account::default());
     let message = Message {
-        public_account_ids: vec![],
+        public_actions: vec![],
         nonces: vec![],
-        public_post_states: vec![],
-        encrypted_private_post_states: vec![],
-        new_commitments: vec![commitment],
-        new_nullifiers: vec![],
+        private_actions: vec![PrivateAction {
+            nullifier: Nullifier::for_account_initialization(&account_id),
+            root: [0; 32],
+            commitment,
+            encrypted_post_state: EncryptedAccountData {
+                ciphertext: Ciphertext::from_inner(vec![]),
+                epk: EphemeralPublicKey(vec![]),
+                view_tag: 0,
+            },
+        }],
         block_validity_window: BlockValidityWindow::new_unbounded(),
         timestamp_validity_window: TimestampValidityWindow::new_unbounded(),
     };

lez/indexer/service/protocol/src/convert.rs

@@ -282,27 +282,30 @@ impl From<PublicMessage> for lee::public_transaction::Message {
 impl From<lee::privacy_preserving_transaction::message::Message> for PrivacyPreservingMessage {
     fn from(value: lee::privacy_preserving_transaction::message::Message) -> Self {
         let lee::privacy_preserving_transaction::message::Message {
-            public_account_ids,
+            public_actions,
             nonces,
-            public_post_states,
-            encrypted_private_post_states,
-            new_commitments,
-            new_nullifiers,
+            private_actions,
             block_validity_window,
             timestamp_validity_window,
         } = value;
         Self {
-            public_account_ids: public_account_ids.into_iter().map(Into::into).collect(),
+            public_account_ids: public_actions.iter().map(|a| a.account_id.into()).collect(),
             nonces: nonces.iter().map(|x| x.0).collect(),
-            public_post_states: public_post_states.into_iter().map(Into::into).collect(),
-            encrypted_private_post_states: encrypted_private_post_states
+            public_post_states: public_actions
                 .into_iter()
-                .map(Into::into)
+                .map(|a| a.post_state.into())
                 .collect(),
-            new_commitments: new_commitments.into_iter().map(Into::into).collect(),
-            new_nullifiers: new_nullifiers
+            encrypted_private_post_states: private_actions
+                .iter()
+                .map(|a| a.encrypted_post_state.clone().into())
+                .collect(),
+            new_commitments: private_actions
+                .iter()
+                .map(|a| a.commitment.clone().into())
+                .collect(),
+            new_nullifiers: private_actions
                 .into_iter()
-                .map(|(n, d)| (n.into(), d.into()))
+                .map(|a| (a.nullifier.into(), a.root.into()))
                 .collect(),
             block_validity_window: block_validity_window.into(),
             timestamp_validity_window: timestamp_validity_window.into(),
@@ -324,26 +327,50 @@ impl TryFrom<PrivacyPreservingMessage> for lee::privacy_preserving_transaction::
             block_validity_window,
             timestamp_validity_window,
         } = value;
+
+        let public_post_states = public_post_states
+            .into_iter()
+            .map(TryInto::try_into)
+            .collect::<Result<Vec<lee_core::account::Account>, _>>()
+            .map_err(|e| lee::error::LeeError::InvalidInput(format!("{e}")))?;
+        let public_actions = public_account_ids
+            .into_iter()
+            .map(Into::into)
+            .zip(public_post_states)
+            .map(|(account_id, post_state)| {
+                lee::privacy_preserving_transaction::message::PublicActionWithID {
+                    account_id,
+                    post_state,
+                }
+            })
+            .collect();
+
+        let private_actions = new_commitments
+            .into_iter()
+            .map(Into::into)
+            .zip(
+                new_nullifiers
+                    .into_iter()
+                    .map(|(n, d)| (n.into(), d.into())),
+            )
+            .zip(encrypted_private_post_states.into_iter().map(Into::into))
+            .map(|((commitment, (nullifier, root)), encrypted_post_state)| {
+                lee_core::PrivateAction {
+                    nullifier,
+                    root,
+                    commitment,
+                    encrypted_post_state,
+                }
+            })
+            .collect();
+
         Ok(Self {
-            public_account_ids: public_account_ids.into_iter().map(Into::into).collect(),
+            public_actions,
             nonces: nonces
                 .iter()
                 .map(|x| lee_core::account::Nonce(*x))
                 .collect(),
-            public_post_states: public_post_states
-                .into_iter()
-                .map(TryInto::try_into)
-                .collect::<Result<Vec<_>, _>>()
-                .map_err(|e| lee::error::LeeError::InvalidInput(format!("{e}")))?,
-            encrypted_private_post_states: encrypted_private_post_states
-                .into_iter()
-                .map(Into::into)
-                .collect(),
-            new_commitments: new_commitments.into_iter().map(Into::into).collect(),
-            new_nullifiers: new_nullifiers
-                .into_iter()
-                .map(|(n, d)| (n.into(), d.into()))
-                .collect(),
+            private_actions,
             block_validity_window: block_validity_window
                 .try_into()
                 .map_err(|e| lee::error::LeeError::InvalidInput(format!("{e}")))?,

lez/sequencer/core/src/tests.rs

@@ -875,8 +875,7 @@ fn private_bridge_withdraw_invocation_is_dropped() {
     )
     .expect("Execution should succeed");
 
-    let message = Message::try_from_circuit_output(vec![bridge_account_id], vec![], output)
-        .expect("Message construction should succeed");
+    let message = Message::from_circuit_output(vec![], output);
     let witness_set =
         lee::privacy_preserving_transaction::WitnessSet::for_message(&message, proof, &[]);
     let tx =

lez/wallet/src/lib.rs

@@ -383,7 +383,6 @@ impl WalletCore {
                 let LeeTransaction::PrivacyPreserving(pp_tx) = &tx else {
                     continue;
                 };
-                pp_tx.message.validate_note_lengths()?;
                 // Sync updates while watching only the init nullifier.
                 self.storage
                     .key_chain_mut()
@@ -550,7 +549,7 @@ impl WalletCore {
         tx: &lee::privacy_preserving_transaction::PrivacyPreservingTransaction,
         acc_decode_mask: &[AccDecodeData],
     ) -> Result<()> {
-        let note_count = tx.message.validate_note_lengths()?;
+        let note_count = tx.message.private_actions.len();
         anyhow::ensure!(
             note_count >= acc_decode_mask.len(),
             "Decode mask has {} entries but the transaction has {note_count} notes",
@@ -655,12 +654,10 @@ impl WalletCore {
                 &program.to_owned(),
             )?;
 
-        let message =
-            lee::privacy_preserving_transaction::message::Message::try_from_circuit_output(
-                acc_manager.public_account_ids(),
-                acc_manager.public_account_nonces(),
-                output,
-            )?;
+        let message = lee::privacy_preserving_transaction::message::Message::from_circuit_output(
+            acc_manager.public_account_nonces(),
+            output,
+        );
 
         let message_hash = message.hash();
         let signatures_public_keys = acc_manager
@@ -785,7 +782,6 @@ impl WalletCore {
                 let LeeTransaction::PrivacyPreserving(pp_tx) = &tx else {
                     continue;
                 };
-                pp_tx.message.validate_note_lengths()?;
                 // Eagerly decrypt note updates using expected nullifiers.
                 let handled = self
                     .storage
@@ -824,18 +820,19 @@ impl WalletCore {
                     &key_chain.viewing_public_key,
                 );
                 message
-                    .encrypted_private_post_states
+                    .private_actions
                     .iter()
                     .enumerate()
-                    .filter(move |(ciph_id, encrypted_data)| {
+                    .filter(move |(ciph_id, action)| {
                         // If we have not decrypted the update using the nullifiers,
                         // the note may be an initialized one, for which we should
                         // scan.
-                        !handled.contains(ciph_id) && encrypted_data.view_tag == view_tag
+                        !handled.contains(ciph_id)
+                            && action.encrypted_post_state.view_tag == view_tag
                     })
-                    .filter_map(move |(ciph_id, encrypted_data)| {
-                        let shared_secret =
-                            key_chain.calculate_shared_secret_receiver(&encrypted_data.epk)?;
+                    .filter_map(move |(ciph_id, action)| {
+                        let shared_secret = key_chain
+                            .calculate_shared_secret_receiver(&action.encrypted_post_state.epk)?;
 
                         decrypt_note_at(message, ciph_id, &shared_secret).map(|(kind, res_acc)| {
                             let npk = &key_chain.nullifier_public_key;
@@ -892,16 +889,14 @@ impl WalletCore {
         for (account_id, npk, vpk, vsk, nsk) in shared_keys {
             let view_tag = EncryptedAccountData::compute_view_tag(&npk, &vpk);
 
-            for (ciph_id, encrypted_data) in
-                message.encrypted_private_post_states.iter().enumerate()
-            {
+            for (ciph_id, action) in message.private_actions.iter().enumerate() {
                 // If already decrypted or the tag does not match, skip.
-                if handled.contains(&ciph_id) || encrypted_data.view_tag != view_tag {
+                if handled.contains(&ciph_id) || action.encrypted_post_state.view_tag != view_tag {
                     continue;
                 }
 
                 let Some(shared_secret) =
-                    SharedSecretKey::decapsulate(&encrypted_data.epk, &vsk.d, &vsk.z)
+                    SharedSecretKey::decapsulate(&action.encrypted_post_state.epk, &vsk.d, &vsk.z)
                 else {
                     continue;
                 };
@@ -938,9 +933,9 @@ fn decrypt_note_at(
     secret: &SharedSecretKey,
 ) -> Option<(lee_core::PrivateAccountKind, Account)> {
     lee_core::EncryptionScheme::decrypt(
-        &message.encrypted_private_post_states[i].ciphertext,
+        &message.private_actions[i].encrypted_post_state.ciphertext,
         secret,
-        &message.new_nullifiers[i].0,
+        &message.private_actions[i].nullifier,
     )
 }
 

lez/wallet/src/storage/key_chain.rs

@@ -390,9 +390,9 @@ impl UserKeyChain {
         index: &mut NullifierIndex,
     ) -> HashSet<usize> {
         let mut handled = HashSet::new();
-        for (i, (old_nullifier, _)) in message.new_nullifiers.iter().enumerate() {
+        for (i, action) in message.private_actions.iter().enumerate() {
             // Get the nullifier information if awaiting the nullifier.
-            let Some(account_id) = index.account_for(old_nullifier) else {
+            let Some(account_id) = index.account_for(&action.nullifier) else {
                 continue;
             };
             // Try decrypting the commitment connected to the nullifier and get the next
@@ -400,7 +400,7 @@ impl UserKeyChain {
             if let Some(new_nullifier) = self.apply_nullifier_update(account_id, message, i) {
                 // Update the index to await for the new state of the account, i.e.
                 // the new nullifier.
-                index.update(old_nullifier, new_nullifier, account_id);
+                index.update(&action.nullifier, new_nullifier, account_id);
                 // Record that this nullifier's position can be skipped for scanning.
                 handled.insert(i);
             }
@@ -416,7 +416,7 @@ impl UserKeyChain {
         message: &Message,
         i: usize,
     ) -> Option<Nullifier> {
-        let encrypted = &message.encrypted_private_post_states[i];
+        let encrypted = &message.private_actions[i].encrypted_post_state;
 
         let (nsk, secret, is_shared) = if let Some(entry) = self.shared_private_account(account_id)
         {
@@ -460,10 +460,9 @@ impl UserKeyChain {
                 &acc.key_chain.private_key_holder.nullifier_secret_key,
             )
         });
-        message
-            .new_nullifiers
-            .iter()
-            .position(|(nullifier, _)| *nullifier == init || Some(nullifier) == update.as_ref())
+        message.private_actions.iter().position(|action| {
+            action.nullifier == init || Some(&action.nullifier) == update.as_ref()
+        })
     }
 
     pub fn add_imported_public_account(&mut self, private_key: lee::PrivateKey) {
@@ -876,7 +875,7 @@ impl Default for UserKeyChain {
 
 #[cfg(test)]
 mod tests {
-    use lee_core::{EncryptionScheme, encryption::EncryptedAccountData};
+    use lee_core::{EncryptionScheme, PrivateAction, encryption::EncryptedAccountData};
 
     use super::*;
 
@@ -921,9 +920,12 @@ mod tests {
         );
 
         let message = Message {
-            encrypted_private_post_states: vec![note],
-            new_commitments: vec![new_commitment],
-            new_nullifiers: vec![(old_nullifier, [0; 32])],
+            private_actions: vec![PrivateAction {
+                nullifier: old_nullifier,
+                commitment: new_commitment,
+                encrypted_post_state: note,
+                ..Default::default()
+            }],
             ..Default::default()
         };
 
@@ -985,9 +987,12 @@ mod tests {
         );
         let note = EncryptedAccountData::new(ciphertext, &npk, &vpk, epk);
         let message = Message {
-            encrypted_private_post_states: vec![note],
-            new_commitments: vec![new_commitment],
-            new_nullifiers: vec![(old_nullifier, [0; 32])],
+            private_actions: vec![PrivateAction {
+                nullifier: old_nullifier,
+                commitment: new_commitment,
+                encrypted_post_state: note,
+                ..Default::default()
+            }],
             ..Default::default()
         };
 
@@ -1047,9 +1052,12 @@ mod tests {
             );
             let note = EncryptedAccountData::new(ciphertext, &npk, &vpk, epk);
             Message {
-                encrypted_private_post_states: vec![note],
-                new_commitments: vec![commitment],
-                new_nullifiers: vec![(spent, [0; 32])],
+                private_actions: vec![PrivateAction {
+                    nullifier: spent,
+                    commitment,
+                    encrypted_post_state: note,
+                    ..Default::default()
+                }],
                 ..Default::default()
             }
         };
@@ -1110,7 +1118,10 @@ mod tests {
             &[9; 32],
         );
         let message = Message {
-            new_nullifiers: vec![(unindexed, [0; 32])],
+            private_actions: vec![PrivateAction {
+                nullifier: unindexed,
+                ..Default::default()
+            }],
             ..Default::default()
         };