feat: Use poseidon for var args hash (#7363)

noir-projects/aztec-nr/aztec/src/hash.nr

@@ -4,7 +4,11 @@ use dep::protocol_types::{
     GENERATOR_INDEX__SECRET_HASH, GENERATOR_INDEX__MESSAGE_NULLIFIER, ARGS_HASH_CHUNK_COUNT,
     GENERATOR_INDEX__FUNCTION_ARGS, ARGS_HASH_CHUNK_LENGTH, MAX_ARGS_LENGTH
 },
-    traits::Hash, hash::{pedersen_hash, compute_siloed_nullifier, sha256_to_field, pedersen_commitment}
+    traits::Hash,
+    hash::{
+    pedersen_hash, compute_siloed_nullifier, sha256_to_field, pedersen_commitment,
+    poseidon2_hash_with_separator
+}
 };
 // Note: pedersen_commitment is used only as a re-export here
 use crate::oracle::logs_traits::{LensForEncryptedLog, ToBytesForUnencryptedLog};
@@ -118,16 +122,16 @@ pub fn hash_args(args: [Field]) -> Field {
             current_chunk_values[index_inside_current_chunk] = args[i];
             index_inside_current_chunk+=1;
             if index_inside_current_chunk == ARGS_HASH_CHUNK_LENGTH {
-                chunks_hashes[current_chunk_index] = pedersen_hash(current_chunk_values, GENERATOR_INDEX__FUNCTION_ARGS);
+                chunks_hashes[current_chunk_index] = poseidon2_hash_with_separator(current_chunk_values, GENERATOR_INDEX__FUNCTION_ARGS);
                 current_chunk_values = [0; ARGS_HASH_CHUNK_LENGTH];
                 current_chunk_index+=1;
                 index_inside_current_chunk = 0;
             }
         }
         if index_inside_current_chunk > 0 {
-            chunks_hashes[current_chunk_index] = pedersen_hash(current_chunk_values, GENERATOR_INDEX__FUNCTION_ARGS);
+            chunks_hashes[current_chunk_index] = poseidon2_hash_with_separator(current_chunk_values, GENERATOR_INDEX__FUNCTION_ARGS);
         }
-        pedersen_hash(chunks_hashes, GENERATOR_INDEX__FUNCTION_ARGS)
+        poseidon2_hash_with_separator(chunks_hashes, GENERATOR_INDEX__FUNCTION_ARGS)
     }
 }
 
@@ -138,7 +142,7 @@ fn compute_var_args_hash() {
         input.add(i as Field);
     }
     let hash = input.hash();
-    assert(hash == 0x11e40f2a780822f7971803048c9a2100579de352e7dadd99981760964da65b57);
+    assert(hash == 0x1cce4dbf69f14c44865919991ee1057922e34d7310ba237d71759aa422621ca9);
 }
 
 #[test]

noir-projects/noir-protocol-circuits/crates/types/src/address/aztec_address.nr

@@ -55,7 +55,11 @@ impl AztecAddress {
 
     pub fn compute(pub_keys_hash: PublicKeysHash, partial_address: PartialAddress) -> AztecAddress {
         AztecAddress::from_field(
-            poseidon2_hash([pub_keys_hash.to_field(), partial_address.to_field(), GENERATOR_INDEX__CONTRACT_ADDRESS_V1])
+            poseidon2_hash(
+                [
+            pub_keys_hash.to_field(), partial_address.to_field(), GENERATOR_INDEX__CONTRACT_ADDRESS_V1 as Field
+        ]
+            )
         )
     }
 

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

@@ -301,13 +301,13 @@ global GENERATOR_INDEX__FUNCTION_LEAF: u32 = 11;
 global GENERATOR_INDEX__CONTRACT_DEPLOYMENT_DATA: u32 = 12;
 global GENERATOR_INDEX__CONSTRUCTOR: u32 = 13;
 global GENERATOR_INDEX__CONSTRUCTOR_ARGS: u32 = 14;
-global GENERATOR_INDEX__CONTRACT_ADDRESS_V1 = 15;
+global GENERATOR_INDEX__CONTRACT_ADDRESS_V1: u32 = 15;
 global GENERATOR_INDEX__CONTRACT_LEAF: u32 = 16;
 global GENERATOR_INDEX__CALL_CONTEXT: u32 = 17;
 global GENERATOR_INDEX__CALL_STACK_ITEM: u32 = 18;
-global GENERATOR_INDEX__CALL_STACK_ITEM_2 = 19;
+global GENERATOR_INDEX__CALL_STACK_ITEM_2: u32 = 19;
 global GENERATOR_INDEX__SECRET_HASH: u32 = 20;
-global GENERATOR_INDEX__L2_TO_L1_MSG = 21;
+global GENERATOR_INDEX__L2_TO_L1_MSG: u32 = 21;
 global GENERATOR_INDEX__TX_CONTEXT: u32 = 22;
 global GENERATOR_INDEX__PUBLIC_LEAF_INDEX: u32 = 23;
 global GENERATOR_INDEX__PUBLIC_DATA_LEAF: u32 = 24;

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

@@ -11,7 +11,7 @@ use crate::{
     MAX_ENCRYPTED_LOGS_PER_TX, MAX_NOTE_ENCRYPTED_LOGS_PER_TX
 },
     merkle_tree::root::root_from_sibling_path, messaging::l2_to_l1_message::ScopedL2ToL1Message,
-    recursion::verification_key::VerificationKey, traits::is_empty,
+    recursion::verification_key::VerificationKey, traits::{is_empty, ToField},
     utils::field::field_from_bytes_32_trunc, point::Point
 };
 
@@ -255,6 +255,22 @@ pub fn poseidon2_hash<let N: u32>(inputs: [Field; N]) -> Field {
     std::hash::poseidon2::Poseidon2::hash(inputs, N)
 }
 
+#[no_predicates]
+pub fn poseidon2_hash_with_separator<N, T>(inputs: [Field; N], separator: T) -> Field where T: ToField {
+    // We manually hash the inputs here, since we cannot express with the type system a constant size inputs array of N + 1
+    let in_len = N + 1;
+    let two_pow_64 = 18446744073709551616;
+    let iv : Field = (in_len as Field) * two_pow_64;
+    let mut sponge = std::hash::poseidon2::Poseidon2::new(iv);
+    sponge.absorb(separator.to_field());
+
+    for i in 0..inputs.len() {
+        sponge.absorb(inputs[i]);
+    }
+
+    sponge.squeeze()
+}
+
 pub fn pedersen_commitment<let N: u32>(inputs: [Field; N], hash_index: u32) -> Point {
     std::hash::pedersen_commitment_with_separator(inputs, hash_index)
 }

yarn-project/circuits.js/src/contract/__snapshots__/contract_address.test.ts.snap

@@ -2,7 +2,7 @@
 
 exports[`ContractAddress computeContractAddressFromInstance 1`] = `"0x1e7ab8ea46fac7865205e7b5f13761e96a789fda67cdd17c46fb1d259c706902"`;
 
-exports[`ContractAddress computeInitializationHash 1`] = `Fr<0x06fdfa55764301f37a1e8f2f7aef196245747858bf8cba8806c30f53ea6c07df>`;
+exports[`ContractAddress computeInitializationHash 1`] = `Fr<0x2993633b581934f500950764c5be63dde8888791cdaf6b02dbc0f5c31460ca57>`;
 
 exports[`ContractAddress computePartialAddress 1`] = `Fr<0x1923a6246e305720b6aaf751fde0342613e93c82e455c3831e28375c16dd40d8>`;
 

yarn-project/circuits.js/src/hash/__snapshots__/hash.test.ts.snap

@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`hash Var args hash matches noir 1`] = `Fr<0x11e40f2a780822f7971803048c9a2100579de352e7dadd99981760964da65b57>`;
+exports[`hash Var args hash matches noir 1`] = `Fr<0x1cce4dbf69f14c44865919991ee1057922e34d7310ba237d71759aa422621ca9>`;
 
 exports[`hash compute secret message hash 1`] = `Fr<0x0dc06f2167e2cd19adf738d1f38469d7f8bff1e26b029816e8230bcd6ab6332e>`;
 
@@ -18,6 +18,6 @@ exports[`hash computes unique note hash 1`] = `Fr<0x1cbdcecec4fe92f6638eb6a8dade
 
 exports[`hash hashes empty function args 1`] = `Fr<0x0000000000000000000000000000000000000000000000000000000000000000>`;
 
-exports[`hash hashes function args 1`] = `Fr<0x0f4da5b77d47f61ea495c0ae504c300bfe608d1f233013c20f34ac7c030d8c14>`;
+exports[`hash hashes function args 1`] = `Fr<0x2cb19d7f1c57660c695e279c0163042f20dc89e4ae7bed9ada08b74790df3204>`;
 
-exports[`hash hashes many function args 1`] = `Fr<0x21fe126bab6cf132a34ef16f23bb6e6a97551d91a2408cd186443e465dc66606>`;
+exports[`hash hashes many function args 1`] = `Fr<0x0f987cfa046685fd829f2cab0cc5e078941719d229df8292924178c77a6f886e>`;

yarn-project/circuits.js/src/hash/hash.ts

@@ -1,6 +1,6 @@
 import { type AztecAddress } from '@aztec/foundation/aztec-address';
 import { padArrayEnd } from '@aztec/foundation/collection';
-import { pedersenHash, pedersenHashBuffer } from '@aztec/foundation/crypto';
+import { pedersenHash, pedersenHashBuffer, poseidon2HashWithSeparator } from '@aztec/foundation/crypto';
 import { Fr } from '@aztec/foundation/fields';
 import { numToUInt8, numToUInt16BE, numToUInt32BE } from '@aztec/foundation/serialize';
 
@@ -107,18 +107,18 @@ export function computeVarArgsHash(args: Fr[]) {
     throw new Error(`Hashing ${args.length} args exceeds max of ${MAX_ARGS_LENGTH}`);
   }
 
-  let chunksHashes = chunk(args, ARGS_HASH_CHUNK_LENGTH).map(c => {
+  let chunksHashes = chunk(args, ARGS_HASH_CHUNK_LENGTH).map((c: Fr[]) => {
     if (c.length < ARGS_HASH_CHUNK_LENGTH) {
       c = padArrayEnd(c, Fr.ZERO, ARGS_HASH_CHUNK_LENGTH);
     }
-    return pedersenHash(c, GeneratorIndex.FUNCTION_ARGS);
+    return poseidon2HashWithSeparator(c, GeneratorIndex.FUNCTION_ARGS);
   });
 
   if (chunksHashes.length < ARGS_HASH_CHUNK_COUNT) {
     chunksHashes = padArrayEnd(chunksHashes, Fr.ZERO, ARGS_HASH_CHUNK_COUNT);
   }
 
-  return pedersenHash(chunksHashes, GeneratorIndex.FUNCTION_ARGS);
+  return poseidon2HashWithSeparator(chunksHashes, GeneratorIndex.FUNCTION_ARGS);
 }
 
 /**

yarn-project/foundation/src/crypto/poseidon/index.ts

@@ -21,6 +21,26 @@ export function poseidon2Hash(input: Fieldable[]): Fr {
   );
 }
 
+/**
+ * Create a poseidon hash (field) from an array of input fields and a domain separator.
+ * @param input - The input fields to hash.
+ * @param separator - The domain separator.
+ * @returns The poseidon hash.
+ */
+export function poseidon2HashWithSeparator(input: Fieldable[], separator: number): Fr {
+  const inputFields = serializeToFields(input);
+  inputFields.unshift(new Fr(separator));
+  return Fr.fromBuffer(
+    Buffer.from(
+      BarretenbergSync.getSingleton()
+        .poseidon2Hash(
+          inputFields.map(i => new FrBarretenberg(i.toBuffer())), // TODO(#4189): remove this stupid conversion
+        )
+        .toBuffer(),
+    ),
+  );
+}
+
 /**
  * Runs a Poseidon2 permutation.
  * @param input the input state. Expected to be of size 4.