refactor!: cleaning up tagging oracles

noir-projects/aztec-nr/aztec/src/messages/encryption/aes128.nr

@@ -393,11 +393,7 @@ mod test {
         test::helpers::test_environment::TestEnvironment,
     };
     use super::AES128;
-    use protocol_types::{
-        address::AztecAddress,
-        indexed_tagging_secret::IndexedTaggingSecret,
-        traits::{Deserialize, FromField},
-    };
+    use protocol_types::{address::AztecAddress, traits::FromField};
     use std::{embedded_curve_ops::EmbeddedCurveScalar, test::OracleMock};
 
     #[test]
@@ -419,10 +415,7 @@ mod test {
             let randomness = 0x0101010101010101010101010101010101010101010101010101010101010101;
             let _ = OracleMock::mock("utilityGetRandomField").returns(randomness).times(1000000);
 
-            let _ = OracleMock::mock("utilityGetIndexedTaggingSecretAsSender").returns(
-                IndexedTaggingSecret::deserialize([69420, 1337]),
-            );
-            let _ = OracleMock::mock("privateIncrementAppTaggingSecretIndexAsSender").returns(());
+            let _ = OracleMock::mock("privateGetNextAppTagAsSender").returns(42);
 
             // Encrypt the message
             let encrypted_message = BoundedVec::from_array(AES128::encrypt(plaintext, recipient));

noir-projects/aztec-nr/aztec/src/messages/logs/utils.nr

@@ -1,6 +1,4 @@
-use crate::oracle::notes::{
-    get_app_tag_as_sender, get_sender_for_tags, increment_app_tagging_secret_index_as_sender,
-};
+use crate::oracle::notes::{get_next_app_tag_as_sender, get_sender_for_tags};
 use dep::protocol_types::address::AztecAddress;
 
 // TODO(#14565): Add constrained tagging
@@ -15,8 +13,7 @@ pub(crate) fn prefix_with_tag<let L: u32>(
         let sender = get_sender_for_tags().expect(
             f"Sender for tags is not set when emitting a private log. Set it by calling `set_sender_for_tags(...)`.",
         );
-        increment_app_tagging_secret_index_as_sender(sender, recipient);
-        get_app_tag_as_sender(sender, recipient)
+        get_next_app_tag_as_sender(sender, recipient)
     };
 
     let mut log_with_tag = [0; L + 1];
@@ -31,30 +28,18 @@ pub(crate) fn prefix_with_tag<let L: u32>(
 
 mod test {
     use super::prefix_with_tag;
-    use protocol_types::{
-        address::AztecAddress,
-        indexed_tagging_secret::IndexedTaggingSecret,
-        traits::{Deserialize, FromField},
-    };
+    use protocol_types::{address::AztecAddress, traits::FromField};
     use std::test::OracleMock;
 
     #[test(should_fail)]
     unconstrained fn no_tag_sender() {
         let recipient = AztecAddress::from_field(2);
 
-        let app_tagging_secret = 42;
-        let index = 5;
-
-        // I am using the deserialize trait instead of directly instantiating the IndexedTaggingSecret struct because
-        // direct instantiation functionality is not exposed.
-        let indexed_tagging_secret = IndexedTaggingSecret::deserialize([app_tagging_secret, index]);
+        let expected_tag = 42;
 
         // Mock the tagging oracles - note privateGetSenderForTags returns none
         let _ = OracleMock::mock("privateGetSenderForTags").returns(Option::<AztecAddress>::none());
-        let _ = OracleMock::mock("utilityGetIndexedTaggingSecretAsSender").returns(
-            indexed_tagging_secret,
-        );
-        let _ = OracleMock::mock("privateIncrementAppTaggingSecretIndexAsSender").returns(());
+        let _ = OracleMock::mock("privateGetNextAppTagAsSender").returns(expected_tag);
 
         let log_without_tag = [1, 2, 3];
         let _ = prefix_with_tag(log_without_tag, recipient);
@@ -65,24 +50,16 @@ mod test {
         let sender = AztecAddress::from_field(1);
         let recipient = AztecAddress::from_field(2);
 
-        let app_tagging_secret = 42;
-        let index = 5;
-
-        // I am using the deserialize trait instead of directly instantiating the IndexedTaggingSecret struct because
-        // direct instantiation functionality is not exposed.
-        let indexed_tagging_secret = IndexedTaggingSecret::deserialize([app_tagging_secret, index]);
+        let expected_tag = 42;
 
         // Mock the tagging oracles
         let _ = OracleMock::mock("privateGetSenderForTags").returns(Option::some(sender));
-        let _ = OracleMock::mock("utilityGetIndexedTaggingSecretAsSender").returns(
-            indexed_tagging_secret,
-        );
-        let _ = OracleMock::mock("privateIncrementAppTaggingSecretIndexAsSender").returns(());
+        let _ = OracleMock::mock("privateGetNextAppTagAsSender").returns(expected_tag);
 
         let log_without_tag = [1, 2, 3];
         let log_with_tag = prefix_with_tag(log_without_tag, recipient);
 
-        let expected_result = [indexed_tagging_secret.compute_tag(recipient), 1, 2, 3];
+        let expected_result = [expected_tag, 1, 2, 3];
 
         // Check tag was prefixed correctly
         assert_eq(log_with_tag, expected_result, "Tag was not prefixed correctly");

noir-projects/aztec-nr/aztec/src/oracle/notes.nr

@@ -1,8 +1,6 @@
 use crate::note::{note_interface::NoteType, retrieved_note::RetrievedNote};
 
-use dep::protocol_types::{
-    address::AztecAddress, indexed_tagging_secret::IndexedTaggingSecret, traits::Packable,
-};
+use dep::protocol_types::{address::AztecAddress, traits::Packable};
 
 /// Notifies the simulator that a note has been created, so that it can be returned in future read requests in the same
 /// transaction. This note should only be added to the non-volatile database if found in an actual block.
@@ -191,43 +189,25 @@ unconstrained fn check_nullifier_exists_oracle(_inner_nullifier: Field) -> bool
 
 // TODO: Oracles below are generic private log oracles and are not specific to notes. Move them somewhere else.
 
-/// Returns the derived app tagging secret ready to be included in a log for a given sender and recipient pair,
-/// siloed for the current contract address.
-pub unconstrained fn get_app_tag_as_sender(sender: AztecAddress, recipient: AztecAddress) -> Field {
-    get_indexed_tagging_secret_as_sender_oracle(sender, recipient).compute_tag(recipient)
-}
-
-#[oracle(utilityGetIndexedTaggingSecretAsSender)]
-unconstrained fn get_indexed_tagging_secret_as_sender_oracle(
-    _sender: AztecAddress,
-    _recipient: AztecAddress,
-) -> IndexedTaggingSecret {}
-
-/// Notifies the simulator that a tag has been used in a note, and to therefore increment the associated index so that
-/// future notes get a different tag and can be discovered by the recipient.
+/// Returns the next app tag for a given sender and recipient pair.
+///
+/// This also notifies the simulator that a tag has been used in a note, and to therefore increment the
+/// associated index so that future notes get a different tag and can be discovered by the recipient.
 /// This change should only be persisted in a non-volatile database if the tagged log is found in an actual block -
 /// otherwise e.g. a reverting transaction can cause the sender to accidentally skip indices and later produce notes
 /// that are not found by the recipient.
-pub fn increment_app_tagging_secret_index_as_sender(sender: AztecAddress, recipient: AztecAddress) {
-    // Safety: This oracle call returns nothing: we only call it for its side effects. It is therefore always safe
-    // to call.
-    unsafe {
-        increment_app_tagging_secret_index_as_sender_wrapper(sender, recipient);
-    }
-}
-
-unconstrained fn increment_app_tagging_secret_index_as_sender_wrapper(
+pub unconstrained fn get_next_app_tag_as_sender(
     sender: AztecAddress,
     recipient: AztecAddress,
-) {
-    increment_app_tagging_secret_index_as_sender_oracle(sender, recipient);
+) -> Field {
+    get_next_app_tag_as_sender_oracle(sender, recipient)
 }
 
-#[oracle(privateIncrementAppTaggingSecretIndexAsSender)]
-unconstrained fn increment_app_tagging_secret_index_as_sender_oracle(
+#[oracle(privateGetNextAppTagAsSender)]
+unconstrained fn get_next_app_tag_as_sender_oracle(
     _sender: AztecAddress,
     _recipient: AztecAddress,
-) {}
+) -> Field {}
 
 /// Gets the sender for tags.
 ///

noir-projects/aztec-nr/aztec/src/oracle/version.nr

@@ -4,7 +4,7 @@
 ///
 /// @dev Whenever a contract function or Noir test is run, the `utilityAssertCompatibleOracleVersion` oracle is called and
 /// if the oracle version is incompatible an error is thrown.
-pub global ORACLE_VERSION: Field = 2;
+pub global ORACLE_VERSION: Field = 3;
 
 /// Asserts that the version of the oracle is compatible with the version expected by the contract.
 pub fn assert_compatible_oracle_version() {
@@ -30,7 +30,7 @@ mod test {
         assert_compatible_oracle_version_oracle(ORACLE_VERSION);
     }
 
-    #[test(should_fail_with = "Incompatible oracle version. TXE is using version '2', but got a request for '318183437'.")]
+    #[test(should_fail_with = "Incompatible oracle version. TXE is using version '3', but got a request for '318183437'.")]
     unconstrained fn incompatible_oracle_version() {
         let arbitrary_incorrect_version = 318183437;
         assert_compatible_oracle_version_oracle(arbitrary_incorrect_version);

noir-projects/noir-protocol-circuits/crates/types/src/lib.nr

@@ -30,7 +30,6 @@ pub mod data;
 pub mod storage;
 pub mod validate;
 pub mod meta;
-pub mod indexed_tagging_secret;
 
 pub mod tests;
 

yarn-project/pxe/src/contract_function_simulator/execution_data_provider.ts

@@ -5,7 +5,6 @@ import type { AztecAddress } from '@aztec/stdlib/aztec-address';
 import type { L2Block } from '@aztec/stdlib/block';
 import type { CompleteAddress, ContractInstance } from '@aztec/stdlib/contract';
 import type { KeyValidationRequest } from '@aztec/stdlib/kernel';
-import { IndexedTaggingSecret } from '@aztec/stdlib/logs';
 import type { NoteStatus } from '@aztec/stdlib/note';
 import { type MerkleTreeId, type NullifierMembershipWitness, PublicDataWitness } from '@aztec/stdlib/trees';
 import type { BlockHeader, NodeStats } from '@aztec/stdlib/tx';
@@ -215,30 +214,13 @@ export interface ExecutionDataProvider {
   assertCompatibleOracleVersion(version: number): void;
 
   /**
-   * Returns the tagging secret for a given sender and recipient pair. For this to work, the ivsk_m of the sender must be known.
-   * Includes the next index to be used used for tagging with this secret.
+   * Returns the next app tag for a given sender and recipient pair.
    * @param contractAddress - The contract address to silo the secret for
    * @param sender - The address sending the note
    * @param recipient - The address receiving the note
-   * @returns A tagging secret that can be used to tag notes.
+   * @returns The computed tag.
    */
-  getIndexedTaggingSecretAsSender(
-    contractAddress: AztecAddress,
-    sender: AztecAddress,
-    recipient: AztecAddress,
-  ): Promise<IndexedTaggingSecret>;
-
-  /**
-   * Increments the tagging secret for a given sender and recipient pair. For this to work, the ivsk_m of the sender must be known.
-   * @param contractAddress - The contract address to silo the secret for
-   * @param sender - The address sending the note
-   * @param recipient - The address receiving the note
-   */
-  incrementAppTaggingSecretIndexAsSender(
-    contractAddress: AztecAddress,
-    sender: AztecAddress,
-    recipient: AztecAddress,
-  ): Promise<void>;
+  getNextAppTagAsSender(contractAddress: AztecAddress, sender: AztecAddress, recipient: AztecAddress): Promise<Fr>;
 
   /**
    * Synchronizes the private logs tagged with scoped addresses and all the senders in the address book. Stores the found

yarn-project/pxe/src/contract_function_simulator/oracle/interfaces.ts

@@ -4,7 +4,7 @@ import type { FunctionSelector, NoteSelector } from '@aztec/stdlib/abi';
 import type { AztecAddress } from '@aztec/stdlib/aztec-address';
 import type { CompleteAddress, ContractInstance } from '@aztec/stdlib/contract';
 import type { KeyValidationRequest } from '@aztec/stdlib/kernel';
-import type { ContractClassLog, IndexedTaggingSecret } from '@aztec/stdlib/logs';
+import type { ContractClassLog } from '@aztec/stdlib/logs';
 import type { Note, NoteStatus } from '@aztec/stdlib/note';
 import { type MerkleTreeId, type NullifierMembershipWitness, PublicDataWitness } from '@aztec/stdlib/trees';
 import type { BlockHeader } from '@aztec/stdlib/tx';
@@ -100,7 +100,6 @@ export interface IUtilityExecutionOracle {
     blockNumber: number,
     numberOfElements: number,
   ): Promise<Fr[]>;
-  utilityGetIndexedTaggingSecretAsSender(sender: AztecAddress, recipient: AztecAddress): Promise<IndexedTaggingSecret>;
   utilityFetchTaggedLogs(pendingTaggedLogArrayBaseSlot: Fr): Promise<void>;
   utilityValidateEnqueuedNotesAndEvents(
     contractAddress: AztecAddress,
@@ -153,8 +152,8 @@ export interface IPrivateExecutionOracle {
     isStaticCall: boolean,
   ): Promise<void>;
   privateNotifySetMinRevertibleSideEffectCounter(minRevertibleSideEffectCounter: number): Promise<void>;
-  privateIncrementAppTaggingSecretIndexAsSender(sender: AztecAddress, recipient: AztecAddress): Promise<void>;
   privateGetSenderForTags(): Promise<AztecAddress | undefined>;
   privateSetSenderForTags(senderForTags: AztecAddress): Promise<void>;
+  privateGetNextAppTagAsSender(sender: AztecAddress, recipient: AztecAddress): Promise<Fr>;
   utilityEmitOffchainEffect(data: Fr[]): Promise<void>;
 }

yarn-project/pxe/src/contract_function_simulator/oracle/oracle.ts

@@ -433,23 +433,12 @@ export class Oracle {
     return Promise.resolve([]);
   }
 
-  async utilityGetIndexedTaggingSecretAsSender([sender]: ACVMField[], [recipient]: ACVMField[]): Promise<ACVMField[]> {
-    const taggingSecret = await this.handlerAsUtility().utilityGetIndexedTaggingSecretAsSender(
+  async privateGetNextAppTagAsSender([sender]: ACVMField[], [recipient]: ACVMField[]): Promise<ACVMField[]> {
+    const tag = await this.handlerAsPrivate().privateGetNextAppTagAsSender(
       AztecAddress.fromString(sender),
       AztecAddress.fromString(recipient),
     );
-    return taggingSecret.toFields().map(toACVMField);
-  }
-
-  async privateIncrementAppTaggingSecretIndexAsSender(
-    [sender]: ACVMField[],
-    [recipient]: ACVMField[],
-  ): Promise<ACVMField[]> {
-    await this.handlerAsPrivate().privateIncrementAppTaggingSecretIndexAsSender(
-      AztecAddress.fromString(sender),
-      AztecAddress.fromString(recipient),
-    );
-    return [];
+    return [toACVMField(tag)];
   }
 
   async utilityFetchTaggedLogs([pendingTaggedLogArrayBaseSlot]: ACVMField[]): Promise<ACVMField[]> {

yarn-project/pxe/src/contract_function_simulator/oracle/private_execution.test.ts

@@ -47,7 +47,6 @@ import {
 } from '@aztec/stdlib/hash';
 import { KeyValidationRequest } from '@aztec/stdlib/kernel';
 import { computeAppNullifierSecretKey, deriveKeys } from '@aztec/stdlib/keys';
-import { IndexedTaggingSecret } from '@aztec/stdlib/logs';
 import { L1Actor, L1ToL2Message, L2Actor } from '@aztec/stdlib/messaging';
 import { Note } from '@aztec/stdlib/note';
 import { makeHeader } from '@aztec/stdlib/testing';
@@ -302,10 +301,9 @@ describe('Private Execution test suite', () => {
       throw new Error(`Unknown address: ${address}. Recipient: ${recipient}, Owner: ${owner}`);
     });
 
-    executionDataProvider.getIndexedTaggingSecretAsSender.mockImplementation(
+    executionDataProvider.getNextAppTagAsSender.mockImplementation(
       (_contractAddress: AztecAddress, _sender: AztecAddress, _recipient: AztecAddress) => {
-        const secret = Fr.random();
-        return Promise.resolve(new IndexedTaggingSecret(secret, 0));
+        return Promise.resolve(Fr.random());
       },
     );
     executionDataProvider.getFunctionArtifact.mockImplementation(async (address, selector) => {

yarn-project/pxe/src/contract_function_simulator/oracle/private_execution_oracle.ts

@@ -185,6 +185,16 @@ export class PrivateExecutionOracle extends UtilityExecutionOracle implements IP
     return Promise.resolve();
   }
 
+  /**
+   * Returns the next app tag for a given sender and recipient pair.
+   * @param sender - The address sending the log
+   * @param recipient - The address receiving the log
+   * @returns An app tag to be used in a log.
+   */
+  public async privateGetNextAppTagAsSender(sender: AztecAddress, recipient: AztecAddress): Promise<Fr> {
+    return await this.executionDataProvider.getNextAppTagAsSender(this.contractAddress, sender, recipient);
+  }
+
   /**
    * Store values in the execution cache.
    * @param values - Values to store.
@@ -567,10 +577,6 @@ export class PrivateExecutionOracle extends UtilityExecutionOracle implements IP
     return this.executionDataProvider.getDebugFunctionName(this.contractAddress, this.callContext.functionSelector);
   }
 
-  public async privateIncrementAppTaggingSecretIndexAsSender(sender: AztecAddress, recipient: AztecAddress) {
-    await this.executionDataProvider.incrementAppTaggingSecretIndexAsSender(this.contractAddress, sender, recipient);
-  }
-
   public utilityEmitOffchainEffect(data: Fr[]): Promise<void> {
     this.offchainEffects.push({ data });
     return Promise.resolve();

yarn-project/pxe/src/contract_function_simulator/oracle/utility_execution_oracle.ts

@@ -6,7 +6,6 @@ import { AztecAddress } from '@aztec/stdlib/aztec-address';
 import type { CompleteAddress, ContractInstance } from '@aztec/stdlib/contract';
 import { siloNullifier } from '@aztec/stdlib/hash';
 import type { KeyValidationRequest } from '@aztec/stdlib/kernel';
-import { IndexedTaggingSecret } from '@aztec/stdlib/logs';
 import type { NoteStatus } from '@aztec/stdlib/note';
 import { type MerkleTreeId, type NullifierMembershipWitness, PublicDataWitness } from '@aztec/stdlib/trees';
 import type { BlockHeader, Capsule } from '@aztec/stdlib/tx';
@@ -264,21 +263,6 @@ export class UtilityExecutionOracle implements IMiscOracle, IUtilityExecutionOra
     this.log[levelName](`${applyStringFormatting(message, fields)}`, { module: `${this.log.module}:debug_log` });
   }
 
-  /**
-   * Returns the tagging secret for a given sender and recipient pair, siloed to the current contract address.
-   * Includes the next index to be used used for tagging with this secret.
-   * For this to work, the ivsk_m of the sender must be known.
-   * @param sender - The address sending the note
-   * @param recipient - The address receiving the note
-   * @returns A tagging secret that can be used to tag notes.
-   */
-  public async utilityGetIndexedTaggingSecretAsSender(
-    sender: AztecAddress,
-    recipient: AztecAddress,
-  ): Promise<IndexedTaggingSecret> {
-    return await this.executionDataProvider.getIndexedTaggingSecretAsSender(this.contractAddress, sender, recipient);
-  }
-
   public async utilityFetchTaggedLogs(pendingTaggedLogArrayBaseSlot: Fr) {
     await this.executionDataProvider.syncTaggedLogs(this.contractAddress, pendingTaggedLogArrayBaseSlot, this.scopes);