fix(bb-prover): create structure for AVM vk

barretenberg/cpp/src/barretenberg/vm/aztec_constants.hpp

@@ -33,6 +33,7 @@
 #define HEADER_LENGTH 24
 #define PUBLIC_CIRCUIT_PUBLIC_INPUTS_LENGTH 691
 #define PUBLIC_CONTEXT_INPUTS_LENGTH 42
+#define AVM_VERIFICATION_KEY_LENGTH_IN_FIELDS 66
 #define SENDER_SELECTOR 0
 #define ADDRESS_SELECTOR 1
 #define STORAGE_ADDRESS_SELECTOR 1

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

@@ -290,6 +290,12 @@ global NESTED_RECURSIVE_PROOF_LENGTH = 439;
 global TUBE_PROOF_LENGTH = RECURSIVE_PROOF_LENGTH; // in the future these can differ
 
 global VERIFICATION_KEY_LENGTH_IN_FIELDS = 128;
+// VK is composed of
+// - circuit size encoded as a fr field element (32 bytes)
+// - num of inputs encoded as a fr field element (32 bytes)
+// - 16 affine elements (curve base field fq) encoded as fr elements takes (16 * 4 * 32 bytes)
+// 16 above refers to the constant AvmFlavor::NUM_PRECOMPUTED_ENTITIES
+global AVM_VERIFICATION_KEY_LENGTH_IN_FIELDS = 2 + 16 * 4;
 
 /**
  * Enumerate the hash_indices which are used for pedersen hashing.

yarn-project/bb-prover/src/avm_proving.test.ts

@@ -1,5 +1,6 @@
 import {
   AvmCircuitInputs,
+  AvmVerificationKeyData,
   AztecAddress,
   ContractStorageRead,
   ContractStorageUpdateRequest,
@@ -49,7 +50,7 @@ import path from 'path';
 import { PublicSideEffectTrace } from '../../simulator/src/public/side_effect_trace.js';
 import { SerializableContractInstance } from '../../types/src/contracts/contract_instance.js';
 import { type BBSuccess, BB_RESULT, generateAvmProof, verifyAvmProof } from './bb/execute.js';
-import { extractVkData } from './verification_key/verification_key_data.js';
+import { extractAvmVkData } from './verification_key/verification_key_data.js';
 
 const TIMEOUT = 60_000;
 const TIMESTAMP = new Fr(99833);
@@ -279,18 +280,10 @@ const proveAndVerifyAvmTestContract = async (
   const proofRes = await generateAvmProof(bbPath, bbWorkingDirectory, avmCircuitInputs, logger);
   expect(proofRes.status).toEqual(BB_RESULT.SUCCESS);
 
-  // Then we test VK extraction.
+  // Then we test VK extraction and serialization.
   const succeededRes = proofRes as BBSuccess;
-  const verificationKey = await extractVkData(succeededRes.vkPath!);
-
-  // VK is composed of
-  // - circuit size encoded as a fr field element (32 bytes)
-  // - num of inputs encoded as a fr field element (32 bytes)
-  // - 16 affine elements (curve base field fq) encoded as fr elements takes (16 * 4 * 32 bytes)
-  // 16 above refers to the constant AvmFlavor::NUM_PRECOMPUTED_ENTITIES
-  // Total number of bytes = 2112
-  const NUM_PRECOMPUTED_ENTITIES = 16;
-  expect(verificationKey.keyAsBytes).toHaveLength(NUM_PRECOMPUTED_ENTITIES * 4 * 32 + 2 * 32);
+  const vkData = await extractAvmVkData(succeededRes.vkPath!);
+  AvmVerificationKeyData.fromBuffer(vkData.toBuffer());
 
   // Then we verify.
   const rawVkPath = path.join(succeededRes.vkPath!, 'vk');

yarn-project/bb-prover/src/prover/bb_prover.ts

@@ -1,6 +1,6 @@
 /* eslint-disable require-await */
 import {
-  type ProofAndVerificationKey,
+  type AvmProofAndVerificationKey,
   type PublicInputsAndRecursiveProof,
   type PublicKernelNonTailRequest,
   type PublicKernelTailRequest,
@@ -11,6 +11,7 @@ import { type CircuitProvingStats, type CircuitWitnessGenerationStats } from '@a
 import {
   AGGREGATION_OBJECT_LENGTH,
   type AvmCircuitInputs,
+  type AvmVerificationKeyData,
   type BaseOrMergeRollupPublicInputs,
   type BaseParityInputs,
   type BaseRollupInputs,
@@ -94,7 +95,7 @@ import type { ACVMConfig, BBConfig } from '../config.js';
 import { ProverInstrumentation } from '../instrumentation.js';
 import { PublicKernelArtifactMapping } from '../mappings/mappings.js';
 import { mapProtocolArtifactNameToCircuitName } from '../stats.js';
-import { extractVkData } from '../verification_key/verification_key_data.js';
+import { extractAvmVkData, extractVkData } from '../verification_key/verification_key_data.js';
 
 const logger = createDebugLogger('aztec:bb-prover');
 
@@ -202,7 +203,7 @@ export class BBNativeRollupProver implements ServerCircuitProver {
   @trackSpan('BBNativeRollupProver.getAvmProof', inputs => ({
     [Attributes.APP_CIRCUIT_NAME]: inputs.functionName,
   }))
-  public async getAvmProof(inputs: AvmCircuitInputs): Promise<ProofAndVerificationKey> {
+  public async getAvmProof(inputs: AvmCircuitInputs): Promise<AvmProofAndVerificationKey> {
     const proofAndVk = await this.createAvmProof(inputs);
     await this.verifyAvmProof(proofAndVk.proof, proofAndVk.verificationKey);
     return proofAndVk;
@@ -626,14 +627,14 @@ export class BBNativeRollupProver implements ServerCircuitProver {
     return provingResult;
   }
 
-  private async createAvmProof(input: AvmCircuitInputs): Promise<ProofAndVerificationKey> {
-    const operation = async (bbWorkingDirectory: string): Promise<ProofAndVerificationKey> => {
+  private async createAvmProof(input: AvmCircuitInputs): Promise<AvmProofAndVerificationKey> {
+    const operation = async (bbWorkingDirectory: string): Promise<AvmProofAndVerificationKey> => {
       const provingResult = await this.generateAvmProofWithBB(input, bbWorkingDirectory);
 
       const rawProof = await fs.readFile(provingResult.proofPath!);
       // TODO(https://github.com/AztecProtocol/aztec-packages/issues/6773): this VK data format is wrong.
       // In particular, the number of public inputs, etc will be wrong.
-      const verificationKey = await extractVkData(provingResult.vkPath!);
+      const verificationKey = await extractAvmVkData(provingResult.vkPath!);
       const proof = new Proof(rawProof, verificationKey.numPublicInputs);
 
       const circuitType = 'avm-circuit' as const;
@@ -765,7 +766,7 @@ export class BBNativeRollupProver implements ServerCircuitProver {
     return await this.verifyWithKey(verificationKey, proof);
   }
 
-  public async verifyAvmProof(proof: Proof, verificationKey: VerificationKeyData) {
+  public async verifyAvmProof(proof: Proof, verificationKey: AvmVerificationKeyData) {
     return await this.verifyWithKeyInternal(proof, verificationKey, verifyAvmProof);
   }
 
@@ -775,7 +776,7 @@ export class BBNativeRollupProver implements ServerCircuitProver {
 
   private async verifyWithKeyInternal(
     proof: Proof,
-    verificationKey: VerificationKeyData,
+    verificationKey: { keyAsBytes: Buffer },
     verificationFunction: VerificationFunction,
   ) {
     const operation = async (bbWorkingDirectory: string) => {

yarn-project/bb-prover/src/test/test_circuit_prover.ts

@@ -1,5 +1,5 @@
 import {
-  type ProofAndVerificationKey,
+  type AvmProofAndVerificationKey,
   type PublicInputsAndRecursiveProof,
   type PublicKernelNonTailRequest,
   type PublicKernelTailRequest,
@@ -8,6 +8,7 @@ import {
 } from '@aztec/circuit-types';
 import {
   type AvmCircuitInputs,
+  AvmVerificationKeyData,
   type BaseOrMergeRollupPublicInputs,
   type BaseParityInputs,
   type BaseRollupInputs,
@@ -475,12 +476,12 @@ export class TestCircuitProver implements ServerCircuitProver {
     );
   }
 
-  public async getAvmProof(_inputs: AvmCircuitInputs): Promise<ProofAndVerificationKey> {
+  public async getAvmProof(_inputs: AvmCircuitInputs): Promise<AvmProofAndVerificationKey> {
     // We can't simulate the AVM because we don't have enough context to do so (e.g., DBs).
     // We just return an empty proof and VK data.
     this.logger.debug('Skipping AVM simulation in TestCircuitProver.');
     await this.delay();
-    return { proof: makeEmptyProof(), verificationKey: VerificationKeyData.makeFake() };
+    return { proof: makeEmptyProof(), verificationKey: AvmVerificationKeyData.makeFake() };
   }
 
   private async delay(): Promise<void> {

yarn-project/bb-prover/src/verification_key/verification_key_data.ts

@@ -1,11 +1,15 @@
 import {
+  AVM_VERIFICATION_KEY_LENGTH_IN_FIELDS,
+  AvmVerificationKeyAsFields,
+  AvmVerificationKeyData,
   Fr,
-  type VERIFICATION_KEY_LENGTH_IN_FIELDS,
+  VERIFICATION_KEY_LENGTH_IN_FIELDS,
   VerificationKeyAsFields,
   VerificationKeyData,
 } from '@aztec/circuits.js';
 import { type Tuple } from '@aztec/foundation/serialize';
 
+import { strict as assert } from 'assert';
 import * as fs from 'fs/promises';
 import * as path from 'path';
 
@@ -25,7 +29,25 @@ export async function extractVkData(vkDirectoryPath: string): Promise<Verificati
   const fields = fieldsJson.map(Fr.fromString);
   // The first item is the hash, this is not part of the actual VK
   const vkHash = fields[0];
+  assert(fields.length === VERIFICATION_KEY_LENGTH_IN_FIELDS, 'Invalid verification key length');
   const vkAsFields = new VerificationKeyAsFields(fields as Tuple<Fr, typeof VERIFICATION_KEY_LENGTH_IN_FIELDS>, vkHash);
   const vk = new VerificationKeyData(vkAsFields, rawBinary);
   return vk;
 }
+
+// TODO: This was adapted from the above function. A refactor might be needed.
+export async function extractAvmVkData(vkDirectoryPath: string): Promise<AvmVerificationKeyData> {
+  const [rawFields, rawBinary] = await Promise.all([
+    fs.readFile(path.join(vkDirectoryPath, VK_FIELDS_FILENAME), { encoding: 'utf-8' }),
+    fs.readFile(path.join(vkDirectoryPath, VK_FILENAME)),
+  ]);
+  const fieldsJson = JSON.parse(rawFields);
+  const fields = fieldsJson.map(Fr.fromString);
+  // The first item is the hash, this is not part of the actual VK
+  // TODO: is the above actually the case?
+  const vkHash = fields[0];
+  assert(fields.length === AVM_VERIFICATION_KEY_LENGTH_IN_FIELDS, 'Invalid AVM verification key length');
+  const vkAsFields = new AvmVerificationKeyAsFields(fields, vkHash);
+  const vk = new AvmVerificationKeyData(vkAsFields, rawBinary);
+  return vk;
+}

yarn-project/circuit-types/src/interfaces/proving-job.ts

@@ -1,5 +1,6 @@
 import {
   type AvmCircuitInputs,
+  type AvmVerificationKeyData,
   type BaseOrMergeRollupPublicInputs,
   type BaseParityInputs,
   type BaseRollupInputs,
@@ -25,9 +26,9 @@ import {
 
 import type { PublicKernelNonTailRequest, PublicKernelTailRequest } from '../tx/processed_tx.js';
 
-export type ProofAndVerificationKey = {
+export type AvmProofAndVerificationKey = {
   proof: Proof;
-  verificationKey: VerificationKeyData;
+  verificationKey: AvmVerificationKeyData;
 };
 
 export type PublicInputsAndRecursiveProof<T> = {
@@ -133,7 +134,7 @@ export type ProvingRequest =
 
 export type ProvingRequestPublicInputs = {
   [ProvingRequestType.PRIVATE_KERNEL_EMPTY]: PublicInputsAndRecursiveProof<KernelCircuitPublicInputs>;
-  [ProvingRequestType.PUBLIC_VM]: ProofAndVerificationKey;
+  [ProvingRequestType.PUBLIC_VM]: AvmProofAndVerificationKey;
 
   [ProvingRequestType.PUBLIC_KERNEL_NON_TAIL]: PublicInputsAndRecursiveProof<PublicKernelCircuitPublicInputs>;
   [ProvingRequestType.PUBLIC_KERNEL_TAIL]: PublicInputsAndRecursiveProof<KernelCircuitPublicInputs>;

yarn-project/circuit-types/src/interfaces/server_circuit_prover.ts

@@ -1,5 +1,5 @@
 import {
-  type ProofAndVerificationKey,
+  type AvmProofAndVerificationKey,
   type PublicInputsAndRecursiveProof,
   type PublicInputsAndTubeProof,
   type PublicKernelNonTailRequest,
@@ -149,7 +149,11 @@ export interface ServerCircuitProver {
    * Create a proof for the AVM circuit.
    * @param inputs - Inputs to the AVM circuit.
    */
-  getAvmProof(inputs: AvmCircuitInputs, signal?: AbortSignal, epochNumber?: number): Promise<ProofAndVerificationKey>;
+  getAvmProof(
+    inputs: AvmCircuitInputs,
+    signal?: AbortSignal,
+    epochNumber?: number,
+  ): Promise<AvmProofAndVerificationKey>;
 }
 
 /**

yarn-project/circuits.js/src/constants.gen.ts

@@ -202,6 +202,7 @@ export const RECURSIVE_PROOF_LENGTH = 439;
 export const NESTED_RECURSIVE_PROOF_LENGTH = 439;
 export const TUBE_PROOF_LENGTH = 439;
 export const VERIFICATION_KEY_LENGTH_IN_FIELDS = 128;
+export const AVM_VERIFICATION_KEY_LENGTH_IN_FIELDS = 66;
 export const SENDER_SELECTOR = 0;
 export const ADDRESS_SELECTOR = 1;
 export const STORAGE_ADDRESS_SELECTOR = 1;