Merge pull request #23 from logos-co/aat/user-atomic-transfer-constraint

goas: user atomic transfer constraint

goas/atomic_asset_transfer/common/src/lib.rs

@@ -44,21 +44,17 @@ pub struct StateWitness {
 }
 
 impl StateWitness {
-    /// Merkle tree over:
-    ///                  root
-    ///              /        \
-    ///            io          state
-    ///          /   \        /     \
-    ///      nonce   txs   zoneid  balances
     pub fn commit(&self) -> StateCommitment {
-        let root = cl::merkle::root([
-            self.nonce,
-            self.included_txs_root(),
-            self.zone_metadata.id(),
-            self.balances_root(),
-        ]);
+        self.state_roots().commit()
+    }
 
-        StateCommitment(root)
+    pub fn state_roots(&self) -> StateRoots {
+        StateRoots {
+            nonce: self.nonce,
+            tx_root: self.included_txs_root(),
+            zone_id: self.zone_metadata.id(),
+            balance_root: self.balances_root(),
+        }
     }
 
     pub fn withdraw(mut self, w: Withdraw) -> Self {
@@ -207,3 +203,35 @@ pub struct IncludedTxWitness {
     pub tx: Tx,
     pub path: Vec<merkle::PathNode>,
 }
+
+impl IncludedTxWitness {
+    pub fn tx_root(&self) -> [u8; 32] {
+        let leaf = merkle::leaf(&self.tx.to_bytes());
+        merkle::path_root(leaf, &self.path)
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct StateRoots {
+    pub nonce: [u8; 32],
+    pub tx_root: [u8; 32],
+    pub zone_id: [u8; 32],
+    pub balance_root: [u8; 32],
+}
+
+impl StateRoots {
+    /// Merkle tree over:
+    ///                  root
+    ///              /        \
+    ///            io          state
+    ///          /   \        /     \
+    ///      nonce   txs   zoneid  balances
+    pub fn commit(&self) -> StateCommitment {
+        StateCommitment(cl::merkle::root([
+            self.nonce,
+            self.tx_root,
+            self.zone_id,
+            self.balance_root,
+        ]))
+    }
+}

goas/atomic_asset_transfer/proof_statements/Cargo.toml

@@ -6,4 +6,6 @@ edition = "2021"
 [dependencies]
 common = { path = "../common" }
 cl = { path = "../../cl/cl" }
+ledger_proof_statements = { path = "../../cl/ledger_proof_statements" }
 serde = { version = "1.0", features = ["derive"] }
+sha2 = "0.10"

goas/atomic_asset_transfer/proof_statements/src/lib.rs

@@ -1,2 +1,14 @@
+pub mod user_note;
 pub mod zone_funds;
 pub mod zone_state;
+
+pub fn assert_is_zone_note(
+    zone_meta: &common::ZoneMetadata,
+    note: &cl::NoteWitness,
+    state_roots: &common::StateRoots,
+) {
+    assert_eq!(state_roots.commit().0, note.state);
+    assert_eq!(zone_meta.id(), state_roots.zone_id);
+    assert_eq!(zone_meta.zone_vk, note.death_constraint);
+    assert_eq!(zone_meta.unit, note.unit);
+}

goas/atomic_asset_transfer/proof_statements/src/user_note.rs

@@ -14,7 +14,7 @@
 ///
 /// The User Notes death constraint requires the following statements to be satisfied
 /// in order for the fee to be captured.
-/// 
+///
 /// 1. w_tx = withdraw(amt=100 NMO, from=Alice) tx was included in Zone A.
 /// 2. d_tx = deposit(amt=100 NMO, to=Alice) tx was included in Zone B.
 /// 3. w_tx is included in Zone A iff d_tx is included in Zone B
@@ -22,3 +22,87 @@
 /// Details:
 /// - the withdrawal in zone A must not be a general withdrawal tx, it must be bound to the user note.
 ///   i.e. the user_note must be present in the ptx for the withdrawal to be valid in Zone A.
+use ledger_proof_statements::death_constraint::DeathConstraintPublic;
+use serde::{Deserialize, Serialize};
+use sha2::{Digest, Sha256};
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct UserIntent {
+    pub zone_a_meta: common::ZoneMetadata,
+    pub zone_b_meta: common::ZoneMetadata,
+    pub withdraw: common::Withdraw,
+    pub deposit: common::Deposit,
+}
+
+impl UserIntent {
+    pub fn commit(&self) -> [u8; 32] {
+        let mut hasher = Sha256::new();
+        hasher.update(b"USER_INTENT_STATE");
+        hasher.update(self.zone_a_meta.id());
+        hasher.update(self.zone_b_meta.id());
+        hasher.update(self.withdraw.to_bytes());
+        hasher.update(self.deposit.to_bytes());
+        hasher.finalize().into()
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct UserAtomicTransfer {
+    // user's note
+    pub user_note: cl::PartialTxInputWitness,
+    pub user_intent: UserIntent,
+
+    // the output state notes which should have included both tx's
+    pub zone_a: cl::PartialTxOutputWitness,
+    pub zone_b: cl::PartialTxOutputWitness,
+
+    // proofs of identies of the above notes
+    pub zone_a_roots: common::StateRoots,
+    pub zone_b_roots: common::StateRoots,
+
+    // proof that zone_a has included this withdrawal
+    pub withdraw_tx: common::IncludedTxWitness,
+    // proof that zone_b has included this deposit
+    pub deposit_tx: common::IncludedTxWitness,
+}
+
+impl UserAtomicTransfer {
+    pub fn assert_constraints(&self) -> DeathConstraintPublic {
+        // user committed to these actions in the user note
+        assert_eq!(self.user_intent.commit(), self.user_note.input.note.state);
+
+        // ensure we are interacting with the correct zone notes
+        crate::assert_is_zone_note(
+            &self.user_intent.zone_a_meta,
+            &self.zone_a.output.note,
+            &self.zone_a_roots,
+        );
+        crate::assert_is_zone_note(
+            &self.user_intent.zone_b_meta,
+            &self.zone_b.output.note,
+            &self.zone_b_roots,
+        );
+
+        // ensure txs were included in the respective zones
+        assert_eq!(self.withdraw_tx.tx_root(), self.zone_a_roots.tx_root);
+        assert_eq!(self.deposit_tx.tx_root(), self.zone_b_roots.tx_root);
+
+        // ensure the txs are the same ones the user requested
+        assert_eq!(
+            common::Tx::Withdraw(self.user_intent.withdraw),
+            self.withdraw_tx.tx
+        );
+        assert_eq!(
+            common::Tx::Deposit(self.user_intent.deposit),
+            self.deposit_tx.tx
+        );
+
+        let input_root = self.user_note.input_root();
+        let output_root = self.zone_a.output_root();
+        assert_eq!(output_root, self.zone_b.output_root());
+
+        let ptx_root = cl::PtxRoot(cl::merkle::node(input_root, output_root));
+        let nf = self.user_note.input.nullifier();
+        DeathConstraintPublic { ptx_root, nf }
+    }
+}

goas/atomic_asset_transfer/risc0_proofs/Cargo.toml

@@ -7,5 +7,4 @@ edition = "2021"
 risc0-build = { version = "1.0" }
 
 [package.metadata.risc0]
-methods = ["spend_zone_funds", "zone_state"]
-
+methods = ["spend_zone_funds", "zone_state", "user_atomic_transfer"]

goas/atomic_asset_transfer/risc0_proofs/user_atomic_transfer/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name = "user_atomic_transfer"
+version = "0.1.0"
+edition = "2021"
+
+[workspace]
+
+[dependencies]
+risc0-zkvm = { version = "1.0", default-features = false, features = ['std'] }
+blake2 = "0.10"
+serde = { version = "1.0", features = ["derive"] }
+bincode = "1"
+common = { path = "../../common" }
+cl = { path = "../../../cl/cl" }
+goas_proof_statements = { path = "../../proof_statements" }
+ledger_proof_statements = { path = "../../../cl/ledger_proof_statements" }
+sha2 = "0.10"
+
+[patch.crates-io]
+# Placing these patch statement in the workspace Cargo.toml will add RISC Zero SHA-256 and bigint
+# multiplication accelerator support for all downstream usages of the following crates.
+sha2 = { git = "https://github.com/risc0/RustCrypto-hashes", tag = "sha2-v0.10.8-risczero.0" }
+# k256 = { git = "https://github.com/risc0/RustCrypto-elliptic-curves", tag = "k256/v0.13.3-risczero.0"  }
+crypto-bigint = { git = "https://github.com/risc0/RustCrypto-crypto-bigint", tag = "v0.5.5-risczero.0" }
+curve25519-dalek = { git = "https://github.com/risc0/curve25519-dalek", tag = "curve25519-4.1.2-risczero.0" }

goas/atomic_asset_transfer/risc0_proofs/user_atomic_transfer/src/main.rs

@@ -0,0 +1,9 @@
+use goas_proof_statements::user_note::UserAtomicTransfer;
+use ledger_proof_statements::death_constraint::DeathConstraintPublic;
+use risc0_zkvm::guest::env;
+
+fn main() {
+    let transfer: UserAtomicTransfer = env::read();
+    let public: DeathConstraintPublic = transfer.assert_constraints();
+    env::commit(&public);
+}