feat: read-requests generated by app circuit, checked in private kernel

circuits/cpp/src/aztec3/circuits/abis/private_circuit_public_inputs.hpp

@@ -28,6 +28,8 @@ template <typename NCT> class PrivateCircuitPublicInputs {
     fr args_hash = 0;
     std::array<fr, RETURN_VALUES_LENGTH> return_values = zero_array<fr, RETURN_VALUES_LENGTH>();
 
+    std::array<fr, READ_REQUESTS_LENGTH> read_requests = zero_array<fr, READ_REQUESTS_LENGTH>();
+
     std::array<fr, NEW_COMMITMENTS_LENGTH> new_commitments = zero_array<fr, NEW_COMMITMENTS_LENGTH>();
     std::array<fr, NEW_NULLIFIERS_LENGTH> new_nullifiers = zero_array<fr, NEW_NULLIFIERS_LENGTH>();
 
@@ -55,10 +57,10 @@ template <typename NCT> class PrivateCircuitPublicInputs {
     boolean operator==(PrivateCircuitPublicInputs<NCT> const& other) const
     {
         return call_context == other.call_context && args_hash == other.args_hash &&
-               return_values == other.return_values && new_commitments == other.new_commitments &&
-               new_nullifiers == other.new_nullifiers && private_call_stack == other.private_call_stack &&
-               public_call_stack == other.public_call_stack && new_l2_to_l1_msgs == other.new_l2_to_l1_msgs &&
-               encrypted_logs_hash == other.encrypted_logs_hash &&
+               return_values == other.return_values && read_requests == other.read_requests &&
+               new_commitments == other.new_commitments && new_nullifiers == other.new_nullifiers &&
+               private_call_stack == other.private_call_stack && public_call_stack == other.public_call_stack &&
+               new_l2_to_l1_msgs == other.new_l2_to_l1_msgs && encrypted_logs_hash == other.encrypted_logs_hash &&
                unencrypted_logs_hash == other.unencrypted_logs_hash &&
                encrypted_log_preimages_length == other.encrypted_log_preimages_length &&
                unencrypted_log_preimages_length == other.unencrypted_log_preimages_length &&
@@ -84,6 +86,8 @@ template <typename NCT> class PrivateCircuitPublicInputs {
             to_ct(args_hash),
             to_ct(return_values),
 
+            to_ct(read_requests),
+
             to_ct(new_commitments),
             to_ct(new_nullifiers),
 
@@ -120,6 +124,8 @@ template <typename NCT> class PrivateCircuitPublicInputs {
             to_nt(args_hash),
             to_nt(return_values),
 
+            to_nt(read_requests),
+
             to_nt(new_commitments),
             to_nt(new_nullifiers),
 
@@ -155,6 +161,8 @@ template <typename NCT> class PrivateCircuitPublicInputs {
         inputs.push_back(args_hash);
         spread_arr_into_vec(return_values, inputs);
 
+        spread_arr_into_vec(read_requests, inputs);
+
         spread_arr_into_vec(new_commitments, inputs);
         spread_arr_into_vec(new_nullifiers, inputs);
 
@@ -193,6 +201,7 @@ template <typename NCT> void read(uint8_t const*& it, PrivateCircuitPublicInputs
     read(it, pis.call_context);
     read(it, pis.args_hash);
     read(it, pis.return_values);
+    read(it, pis.read_requests);
     read(it, pis.new_commitments);
     read(it, pis.new_nullifiers);
     read(it, pis.private_call_stack);
@@ -219,6 +228,7 @@ void write(std::vector<uint8_t>& buf, PrivateCircuitPublicInputs<NCT> const& pri
     write(buf, pis.call_context);
     write(buf, pis.args_hash);
     write(buf, pis.return_values);
+    write(buf, pis.read_requests);
     write(buf, pis.new_commitments);
     write(buf, pis.new_nullifiers);
     write(buf, pis.private_call_stack);
@@ -244,6 +254,7 @@ std::ostream& operator<<(std::ostream& os, PrivateCircuitPublicInputs<NCT> const
     return os << "call_context: " << pis.call_context << "\n"
               << "args_hash: " << pis.args_hash << "\n"
               << "return_values: " << pis.return_values << "\n"
+              << "read_requests: " << pis.read_requests << "\n"
               << "new_commitments: " << pis.new_commitments << "\n"
               << "new_nullifiers: " << pis.new_nullifiers << "\n"
               << "private_call_stack: " << pis.private_call_stack << "\n"
@@ -274,6 +285,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
     opt_fr args_hash;
     std::array<opt_fr, RETURN_VALUES_LENGTH> return_values;
 
+    std::array<opt_fr, READ_REQUESTS_LENGTH> read_requests;
+
     std::array<opt_fr, NEW_COMMITMENTS_LENGTH> new_commitments;
     std::array<opt_fr, NEW_NULLIFIERS_LENGTH> new_nullifiers;
 
@@ -301,6 +314,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
                                             opt_fr const& args_hash,
                                             std::array<opt_fr, RETURN_VALUES_LENGTH> const& return_values,
 
+                                            std::array<opt_fr, READ_REQUESTS_LENGTH> const& read_requests,
+
                                             std::array<opt_fr, NEW_COMMITMENTS_LENGTH> const& new_commitments,
                                             std::array<opt_fr, NEW_NULLIFIERS_LENGTH> const& new_nullifiers,
 
@@ -323,6 +338,7 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
         : call_context(call_context)
         , args_hash(args_hash)
         , return_values(return_values)
+        , read_requests(read_requests)
         , new_commitments(new_commitments)
         , new_nullifiers(new_nullifiers)
         , private_call_stack(private_call_stack)
@@ -349,6 +365,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
         new_inputs.args_hash = std::nullopt;
         new_inputs.return_values.fill(std::nullopt);
 
+        new_inputs.read_requests.fill(std::nullopt);
+
         new_inputs.new_commitments.fill(std::nullopt);
         new_inputs.new_nullifiers.fill(std::nullopt);
 
@@ -401,6 +419,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
         make_unused_element_zero(composer, args_hash);
         make_unused_array_elements_zero(composer, return_values);
 
+        make_unused_array_elements_zero(composer, read_requests);
+
         make_unused_array_elements_zero(composer, new_commitments);
         make_unused_array_elements_zero(composer, new_nullifiers);
 
@@ -437,6 +457,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
         (*args_hash).set_public();
         set_array_public(return_values);
 
+        set_array_public(read_requests);
+
         set_array_public(new_commitments);
         set_array_public(new_nullifiers);
 
@@ -475,6 +497,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
             to_ct(args_hash),
             to_ct(return_values),
 
+            to_ct(read_requests),
+
             to_ct(new_commitments),
             to_ct(new_nullifiers),
 
@@ -514,6 +538,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
             to_nt(args_hash),
             to_nt(return_values),
 
+            to_nt(read_requests),
+
             to_nt(new_commitments),
             to_nt(new_nullifiers),
 
@@ -554,6 +580,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
         inputs.push_back(*args_hash);
         spread_arr_opt_into_vec(return_values, inputs);
 
+        spread_arr_opt_into_vec(read_requests, inputs);
+
         spread_arr_opt_into_vec(new_commitments, inputs);
         spread_arr_opt_into_vec(new_nullifiers, inputs);
 
@@ -588,6 +616,8 @@ template <typename NCT> class OptionalPrivateCircuitPublicInputs {
             .args_hash = args_hash.value(),
             .return_values = map(return_values, get_value),
 
+            .read_requests = map(read_requests, get_value),
+
             .new_commitments = map(new_commitments, get_value),
             .new_nullifiers = map(new_nullifiers, get_value),
 
@@ -687,6 +717,7 @@ void read(uint8_t const*& it, OptionalPrivateCircuitPublicInputs<NCT>& private_c
     read(it, pis.call_context);
     read(it, pis.args_hash);
     read(it, pis.return_values);
+    read(it, pis.read_requests);
     read(it, pis.new_commitments);
     read(it, pis.new_nullifiers);
     read(it, pis.private_call_stack);
@@ -713,6 +744,7 @@ void write(std::vector<uint8_t>& buf, OptionalPrivateCircuitPublicInputs<NCT> co
     write(buf, pis.call_context);
     write(buf, pis.args_hash);
     write(buf, pis.return_values);
+    write(buf, pis.read_requests);
     write(buf, pis.new_commitments);
     write(buf, pis.new_nullifiers);
     write(buf, pis.private_call_stack);
@@ -737,6 +769,7 @@ std::ostream& operator<<(std::ostream& os, OptionalPrivateCircuitPublicInputs<NC
     return os << "call_context: " << pis.call_context << "\n"
               << "args_hash: " << pis.args_hash << "\n"
               << "return_values: " << pis.return_values << "\n"
+              << "read_requests: " << pis.read_requests << "\n"
               << "new_commitments: " << pis.new_commitments << "\n"
               << "new_nullifiers: " << pis.new_nullifiers << "\n"
               << "private_call_stack: " << pis.private_call_stack << "\n"

circuits/cpp/src/aztec3/circuits/abis/private_kernel/private_call_data.hpp

@@ -36,6 +36,9 @@ template <typename NCT> struct PrivateCallData {
     MembershipWitness<NCT, FUNCTION_TREE_HEIGHT> function_leaf_membership_witness{};
     MembershipWitness<NCT, CONTRACT_TREE_HEIGHT> contract_leaf_membership_witness{};
 
+    std::array<MembershipWitness<NCT, PRIVATE_DATA_TREE_HEIGHT>, READ_REQUESTS_LENGTH>
+        read_request_membership_witnesses{};
+
     fr portal_contract_address = 0;  // an ETH address
     fr acir_hash = 0;
 
@@ -46,6 +49,7 @@ template <typename NCT> struct PrivateCallData {
                private_call_stack_preimages == other.private_call_stack_preimages && vk == other.vk &&
                function_leaf_membership_witness == other.function_leaf_membership_witness &&
                contract_leaf_membership_witness == other.contract_leaf_membership_witness &&
+               read_request_membership_witnesses == other.read_request_membership_witnesses &&
                portal_contract_address == other.portal_contract_address && acir_hash == other.acir_hash;
     };
 
@@ -72,6 +76,9 @@ template <typename NCT> struct PrivateCallData {
             to_circuit_type(function_leaf_membership_witness),
             to_circuit_type(contract_leaf_membership_witness),
 
+            aztec3::utils::types::to_ct<Composer, MembershipWitness<CT, PRIVATE_DATA_TREE_HEIGHT>>(
+                composer, read_request_membership_witnesses),
+
             to_ct(portal_contract_address),
             to_ct(acir_hash),
         };
@@ -90,6 +97,7 @@ template <typename NCT> void read(uint8_t const*& it, PrivateCallData<NCT>& obj)
     read(it, obj.vk);
     read(it, obj.function_leaf_membership_witness);
     read(it, obj.contract_leaf_membership_witness);
+    read(it, obj.read_request_membership_witnesses);
     read(it, obj.portal_contract_address);
     read(it, obj.acir_hash);
 };
@@ -104,6 +112,7 @@ template <typename NCT> void write(std::vector<uint8_t>& buf, PrivateCallData<NC
     write(buf, *obj.vk);
     write(buf, obj.function_leaf_membership_witness);
     write(buf, obj.contract_leaf_membership_witness);
+    write(buf, obj.read_request_membership_witnesses);
     write(buf, obj.portal_contract_address);
     write(buf, obj.acir_hash);
 };
@@ -122,6 +131,8 @@ template <typename NCT> std::ostream& operator<<(std::ostream& os, PrivateCallDa
               << obj.function_leaf_membership_witness << "\n"
               << "contract_leaf_membership_witness:\n"
               << obj.contract_leaf_membership_witness << "\n"
+              << "read_request_membership_witnesses:\n"
+              << obj.read_request_membership_witnesses << "\n"
               << "portal_contract_address: " << obj.portal_contract_address << "\n"
               << "acir_hash: " << obj.acir_hash << "\n";
 }

circuits/cpp/src/aztec3/circuits/hash.hpp

@@ -16,6 +16,7 @@ namespace aztec3::circuits {
 using abis::FunctionData;
 using aztec3::circuits::abis::ContractLeafPreimage;
 using aztec3::circuits::abis::FunctionLeafPreimage;
+using MerkleTree = stdlib::merkle_tree::MemoryTree;
 
 template <typename NCT> typename NCT::fr compute_var_args_hash(std::vector<typename NCT::fr> args)
 {
@@ -96,8 +97,8 @@ typename NCT::fr silo_nullifier(typename NCT::address contract_address, typename
  * @tparam NCT Operate on NativeTypes or CircuitTypes
  * @tparam N The number of elements in the sibling path
  * @param leaf The leaf element of the Merkle tree
- * @param leafIndex The index of the leaf element in the Merkle tree
- * @param siblingPath The nodes representing the merkle siblings of the leaf, its parent,
+ * @param leaf_index The index of the leaf element in the Merkle tree
+ * @param sibling_path The nodes representing the merkle siblings of the leaf, its parent,
  * the next parent, etc up to the sibling below the root
  * @return The computed Merkle tree root.
  *
@@ -106,15 +107,15 @@ typename NCT::fr silo_nullifier(typename NCT::address contract_address, typename
  */
 template <typename NCT, size_t N>
 typename NCT::fr root_from_sibling_path(typename NCT::fr const& leaf,
-                                        typename NCT::uint32 const& leafIndex,
-                                        std::array<typename NCT::fr, N> const& siblingPath)
+                                        typename NCT::uint32 const& leaf_index,
+                                        std::array<typename NCT::fr, N> const& sibling_path)
 {
     auto node = leaf;
     for (size_t i = 0; i < N; i++) {
-        if (leafIndex & (1 << i)) {
-            node = NCT::merkle_hash(siblingPath[i], node);
+        if (leaf_index & (1 << i)) {
+            node = NCT::merkle_hash(sibling_path[i], node);
         } else {
-            node = NCT::merkle_hash(node, siblingPath[i]);
+            node = NCT::merkle_hash(node, sibling_path[i]);
         }
     }
     return node;  // root
@@ -129,8 +130,8 @@ typename NCT::fr root_from_sibling_path(typename NCT::fr const& leaf,
  * @tparam NCT Operate on NativeTypes or CircuitTypes
  * @tparam N The number of elements in the sibling path
  * @param leaf The leaf element of the Merkle tree
- * @param leafIndex The index of the leaf element in the Merkle tree
- * @param siblingPath The nodes representing the merkle siblings of the leaf, its parent,
+ * @param leaf_index The index of the leaf element in the Merkle tree
+ * @param sibling_path The nodes representing the merkle siblings of the leaf, its parent,
  * the next parent, etc up to the sibling below the root
  * @return The computed Merkle tree root.
  *
@@ -139,22 +140,52 @@ typename NCT::fr root_from_sibling_path(typename NCT::fr const& leaf,
  */
 template <typename NCT, size_t N>
 typename NCT::fr root_from_sibling_path(typename NCT::fr const& leaf,
-                                        typename NCT::fr const& leafIndex,
-                                        std::array<typename NCT::fr, N> const& siblingPath)
+                                        typename NCT::fr const& leaf_index,
+                                        std::array<typename NCT::fr, N> const& sibling_path)
 {
     auto node = leaf;
-    uint256_t index = leafIndex;
+    uint256_t index = leaf_index;
     for (size_t i = 0; i < N; i++) {
         if (index & 1) {
-            node = NCT::merkle_hash(siblingPath[i], node);
+            node = NCT::merkle_hash(sibling_path[i], node);
         } else {
-            node = NCT::merkle_hash(node, siblingPath[i]);
+            node = NCT::merkle_hash(node, sibling_path[i]);
         }
         index >>= uint256_t(1);
     }
     return node;  // root
 }
 
+/**
+ * @brief Get the sibling path of an item in a given merkle tree
+ *
+ * WARNING: this function is for testing purposes only! leaf_index is an fr
+ * in `MembershipWitness` but is a `size_t` here. This could lead to overflows
+ * on `1 << i` if the tree is large enough.
+ *
+ * @tparam N height of tree (not including root)
+ * @param tree merkle tree to operate on
+ * @param leaf_index index of the leaf to get path for
+ * @param subtree_depth_to_skip skip some number of bottom layers
+ * @return std::array<fr, N> sibling path
+ */
+template <size_t N>
+std::array<fr, N> get_sibling_path(MerkleTree& tree, size_t leaf_index, size_t const& subtree_depth_to_skip)
+{
+    std::array<fr, N> sibling_path;
+    auto path = tree.get_hash_path(leaf_index);
+    // slice out the skip
+    leaf_index = leaf_index >> (subtree_depth_to_skip);
+    for (size_t i = 0; i < N; i++) {
+        if (leaf_index & (1 << i)) {
+            sibling_path[i] = path[subtree_depth_to_skip + i].first;
+        } else {
+            sibling_path[i] = path[subtree_depth_to_skip + i].second;
+        }
+    }
+    return sibling_path;
+}
+
 template <typename NCT, typename Composer, size_t SIZE>
 void check_membership(Composer& composer,
                       typename NCT::fr const& value,