feat(gateway-contracts): implement coprocessor contexts

.github/workflows/gateway-contracts-upgrade-tests.yml

@@ -33,10 +33,7 @@ jobs:
   sc-upgrade:
     name: gateway-contracts-upgrade-tests/sc-upgrade (bpr)
     needs: check-changes
-    # if: ${{ needs.check-changes.outputs.changes-gw-contracts == 'true' }}
-    # TODO: Re-enable the upgrade tests once fhevm 0.9 is released
-    # See https://github.com/zama-ai/fhevm-internal/issues/439
-    if: false
+    if: ${{ needs.check-changes.outputs.changes-gw-contracts == 'true' }}
     permissions:
       contents: 'read' # Required to checkout repository code
       checks: 'write' # Required to create GitHub checks for test results
@@ -48,7 +45,7 @@ jobs:
         with:
           # This version should be updated whenever we release new contract versions or
           # touch a contract upgrade path.
-          ref: v0.8.0-6
+          ref: v0.9.1-1
           path: previous-fhevm
           persist-credentials: 'false'
 
@@ -209,15 +206,17 @@ jobs:
       # See https://github.com/zama-ai/fhevm-internal/issues/379
       - name: Upgrade KMSGeneration contract
         working-directory: current-fhevm/gateway-contracts
+        # TODO: Re-enable the upgrade tests once the contract needs an upgrade
+        if: false
         env:
           DOTENV_CONFIG_PATH: .env
           HARDHAT_NETWORK: staging
           CHAIN_ID_GATEWAY: 54321
           RPC_URL: http://localhost:8546
         run: |
-          npx hardhat task:upgradeKmsGeneration \
-            --current-implementation previous-contracts/KmsGeneration.sol:KmsGeneration \
-            --new-implementation contracts/KmsGeneration.sol:KmsGeneration \
+          npx hardhat task:upgradeKMSGeneration \
+            --current-implementation previous-contracts/KMSGeneration.sol:KMSGeneration \
+            --new-implementation contracts/KMSGeneration.sol:KMSGeneration \
             --use-internal-proxy-address true \
             --verify-contract false
 

gateway-contracts/.env.example

@@ -55,24 +55,30 @@ KMS_SIGNER_ADDRESS_3="0xDb216ECeC4cEd51CdfD9609b6Ce7653aB04f6cAd" # accounts[10]
 KMS_NODE_IP_ADDRESS_3="127.0.0.4" # (string)
 KMS_NODE_STORAGE_URL_3="s3://kms-bucket-4" # (string)
 
+# Coprocessor blob
+COPROCESSORS_BLOB="0x54c4e861e4036812a7d137acfbf134758045b3e8feec003d838082fbd4ae6f2192ea668d9bb73abedd159ffa9d09d3d5846d9c4ac19c40aa16e894ae491f3cc3" # (bytes)
+
 # Coprocessors
 # The number of coprocessors must be lower or equal to the number of coprocessors' metadata defined below
 NUM_COPROCESSORS="3" # (number)
 
 # Coprocessor 1
+COPROCESSOR_NAME_0="Coprocessor 1" # (string)
 COPROCESSOR_TX_SENDER_ADDRESS_0="0x6518D50aDc9036Df37119eA465a8159E34417E2E" # accounts[11] (address)
 COPROCESSOR_SIGNER_ADDRESS_0="0xa5eE8292dA52d8234248709F3E217ffEBA5E8312" # accounts[12] (address)
-COPROCESSOR_S3_BUCKET_URL_0="s3://coprocessor-bucket-1" # (string)
+COPROCESSOR_STORAGE_URL_0="s3://coprocessor-bucket-1" # (string)
 
 # Coprocessor 2
+COPROCESSOR_NAME_1="Coprocessor 2" # (string)
 COPROCESSOR_TX_SENDER_ADDRESS_1="0xCFbF539CB91c92ace0343c5B0487149Ad0b82078" # accounts[13] (address)
 COPROCESSOR_SIGNER_ADDRESS_1="0xA951F315d5FD35Cac111dFB5250DF231FB8eF905" # accounts[14] (address)
-COPROCESSOR_S3_BUCKET_URL_1="s3://coprocessor-bucket-2" # (string)
+COPROCESSOR_STORAGE_URL_1="s3://coprocessor-bucket-2" # (string)
 
 # Coprocessor 3
+COPROCESSOR_NAME_2="Coprocessor 3" # (string)
 COPROCESSOR_TX_SENDER_ADDRESS_2="0x3C0033584da3A0f61AA5C7bde50eAF3642875a21" # accounts[15] (address)
 COPROCESSOR_SIGNER_ADDRESS_2="0x420AF5A5BBfAd922aE5a501d9a8Bf70a55F52E03" # accounts[16] (address)
-COPROCESSOR_S3_BUCKET_URL_2="s3://coprocessor-bucket-3" # (string)
+COPROCESSOR_STORAGE_URL_2="s3://coprocessor-bucket-3" # (string)
 
 # Custodians
 # The number of custodians must be lower or equal to the number of custodians' metadata defined below

gateway-contracts/Makefile

@@ -130,3 +130,15 @@ prerelease:
 # Get the size of the contracts
 get-contracts-sized:
 	forge build --sizes
+
+# Get the list of coprocessor signers from the active coprocessor context registered in the gateway
+get-coprocessor-signers:
+	DOTENV_CONFIG_PATH=$(ENV_PATH) npx hardhat task:getCoprocessorSigners --use-internal-proxy-address true --network localGateway
+
+# Get the list of KMS signers registered in the gateway
+get-kms-signers:
+	DOTENV_CONFIG_PATH=$(ENV_PATH) npx hardhat task:getKmsSigners --use-internal-proxy-address true --network localGateway
+
+# Get the list of host chains registered in the gateway
+get-host-chains:
+	DOTENV_CONFIG_PATH=$(ENV_PATH) npx hardhat task:getHostChains --use-internal-proxy-address true --network localGateway

gateway-contracts/contracts/CiphertextCommits.sol

@@ -1,20 +1,33 @@
 // SPDX-License-Identifier: BSD-3-Clause-Clear
 pragma solidity ^0.8.24;
-import { gatewayConfigAddress, kmsGenerationAddress } from "../addresses/GatewayAddresses.sol";
+import {
+    gatewayConfigAddress,
+    kmsGenerationAddress,
+    coprocessorContextsAddress
+} from "../addresses/GatewayAddresses.sol";
 import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";
 import { ICiphertextCommits } from "./interfaces/ICiphertextCommits.sol";
 import { IGatewayConfig } from "./interfaces/IGatewayConfig.sol";
 import { IKMSGeneration } from "./interfaces/IKMSGeneration.sol";
+import { ICoprocessorContexts } from "./interfaces/ICoprocessorContexts.sol";
 import { UUPSUpgradeableEmptyProxy } from "./shared/UUPSUpgradeableEmptyProxy.sol";
 import { GatewayConfigChecks } from "./shared/GatewayConfigChecks.sol";
 import { GatewayOwnable } from "./shared/GatewayOwnable.sol";
 import { CiphertextMaterial, SnsCiphertextMaterial } from "./shared/Structs.sol";
+import { ContextStatus } from "./shared/Enums.sol";
+import { ContextChecks } from "./shared/ContextChecks.sol";
 
 /**
  * @title CiphertextCommits smart contract
  * @notice See {ICiphertextCommits}.
  */
-contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, GatewayOwnable, GatewayConfigChecks {
+contract CiphertextCommits is
+    ICiphertextCommits,
+    UUPSUpgradeableEmptyProxy,
+    GatewayOwnable,
+    GatewayConfigChecks,
+    ContextChecks
+{
     /**
      * @notice The address of the GatewayConfig contract, used for fetching information about coprocessors.
      */
@@ -25,14 +38,17 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
      */
     IKMSGeneration private constant KMS_GENERATION = IKMSGeneration(kmsGenerationAddress);
 
+    /// @notice The address of the CoprocessorContexts contract, used for fetching information about coprocessors.
+    ICoprocessorContexts private constant COPROCESSOR_CONTEXTS = ICoprocessorContexts(coprocessorContextsAddress);
+
     /**
      * @dev The following constants are used for versioning the contract. They are made private
      * in order to force derived contracts to consider a different version. Note that
      * they can still define their own private constants with the same name.
      */
     string private constant CONTRACT_NAME = "CiphertextCommits";
     uint256 private constant MAJOR_VERSION = 0;
-    uint256 private constant MINOR_VERSION = 1;
+    uint256 private constant MINOR_VERSION = 2;
     uint256 private constant PATCH_VERSION = 0;
 
     /**
@@ -41,7 +57,7 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
      * This constant does not represent the number of time a specific contract have been upgraded,
      * as a contract deployed from version VX will have a REINITIALIZER_VERSION > 2.
      */
-    uint64 private constant REINITIALIZER_VERSION = 2;
+    uint64 private constant REINITIALIZER_VERSION = 3;
 
     /**
      * @notice The contract's variable storage struct (@dev see ERC-7201)
@@ -104,44 +120,57 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
 
     /**
      * @notice Re-initializes the contract from V1.
-     * @dev Define a `reinitializeVX` function once the contract needs to be upgraded.
      */
     /// @custom:oz-upgrades-unsafe-allow missing-initializer-call
     /// @custom:oz-upgrades-validate-as-initializer
-    // function reinitializeV2() public virtual reinitializer(REINITIALIZER_VERSION) {}
+    function reinitializeV2() public virtual reinitializer(REINITIALIZER_VERSION) {}
 
-    /**
-     * @notice See {ICiphertextCommits-addCiphertextMaterial}.
-     */
+    /// @notice See {ICiphertextCommits-addCiphertextMaterial}.
     function addCiphertextMaterial(
         bytes32 ctHandle,
         uint256 keyId,
         bytes32 ciphertextDigest,
         bytes32 snsCiphertextDigest
-    ) external virtual onlyCoprocessorTxSender onlyHandleFromRegisteredHostChain(ctHandle) {
-        CiphertextCommitsStorage storage $ = _getCiphertextCommitsStorage();
-
-        // Check if the coprocessor transaction sender has already added the ciphertext handle.
-        if ($.alreadyAddedCoprocessorTxSenders[ctHandle][msg.sender]) {
-            revert CoprocessorAlreadyAdded(ctHandle, msg.sender);
-        }
-
+    ) external virtual onlyHandleFromRegisteredHostChain(ctHandle) refreshCoprocessorContextStatuses {
         // The addCiphertextHash is the hash of all received input arguments which means that multiple
         // Coprocessors can only have a consensus on a ciphertext material with the same information.
         // This hash is used to differentiate different calls to the function, in particular when
         // tracking the consensus on the received ciphertext material.
         // Note that chainId is not included in the hash because it is already contained in the ctHandle.
         bytes32 addCiphertextHash = keccak256(abi.encode(ctHandle, keyId, ciphertextDigest, snsCiphertextDigest));
-        $.addCiphertextHashCounters[addCiphertextHash]++;
 
-        // Associate the handle to coprocessor context ID 1 to anticipate their introduction in V2.
-        // Only set the context ID if it hasn't been set yet to avoid multiple identical SSTOREs.
-        if ($.addCiphertextContextId[addCiphertextHash] == 0) {
-            $.addCiphertextContextId[addCiphertextHash] = 1;
+        CiphertextCommitsStorage storage $ = _getCiphertextCommitsStorage();
+
+        // Get the context ID from the input verification context ID mapping
+        // This ID may be 0 (invalid) if this is the first addCiphertextMaterial call for this
+        // addCiphertextHash (see right below)
+        uint256 contextId = $.addCiphertextContextId[addCiphertextHash];
+
+        // If the context ID is null, get the active coprocessor context's ID and associate it to
+        // this ciphertext material addition
+        if (contextId == 0) {
+            contextId = COPROCESSOR_CONTEXTS.getActiveCoprocessorContextId();
+            $.addCiphertextContextId[addCiphertextHash] = contextId;
+
+            // Else, that means a coprocessor already started to add the ciphertext material
+            // and we need to check that the context is active or suspended
+            // If it is not, that means the context is no longer valid for this operation and we revert
+        } else if (!COPROCESSOR_CONTEXTS.isCoprocessorContextOperating(contextId)) {
+            ContextStatus contextStatus = COPROCESSOR_CONTEXTS.getCoprocessorContextStatus(contextId);
+            revert InvalidCoprocessorContextAddCiphertext(ctHandle, contextId, contextStatus);
         }
 
-        // It is ok to only the handle can be considered here as a handle should only be added once
-        // in the contract anyway
+        // Only accept coprocessor transaction senders from the same context
+        _checkIsCoprocessorTxSender(contextId, msg.sender);
+
+        // Check if the coprocessor transaction sender has already added the ciphertext handle.
+        if ($.alreadyAddedCoprocessorTxSenders[ctHandle][msg.sender]) {
+            revert CoprocessorAlreadyAdded(ctHandle, msg.sender);
+        }
+
+        $.addCiphertextHashCounters[addCiphertextHash]++;
+
+        // It is ok to only consider the handle here as it is only added once in the contract anyway
         $.alreadyAddedCoprocessorTxSenders[ctHandle][msg.sender] = true;
 
         // Store the coprocessor transaction sender address for the ciphertext material addition
@@ -154,9 +183,10 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
 
         // Send the event if and only if the consensus is reached in the current response call.
         // This means a "late" response will not be reverted, just ignored and no event will be emitted
+        // Besides, consensus only considers the coprocessors of the same context
         if (
             !$.isCiphertextMaterialAdded[ctHandle] &&
-            _isConsensusReached($.addCiphertextHashCounters[addCiphertextHash])
+            _isConsensusReached(contextId, $.addCiphertextHashCounters[addCiphertextHash])
         ) {
             $.ciphertextDigests[ctHandle] = ciphertextDigest;
             $.snsCiphertextDigests[ctHandle] = snsCiphertextDigest;
@@ -170,12 +200,7 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
             // by only knowing the handle, since a consensus can only happen once per handle
             $.ctHandleConsensusHash[ctHandle] = addCiphertextHash;
 
-            emit AddCiphertextMaterial(
-                ctHandle,
-                ciphertextDigest,
-                snsCiphertextDigest,
-                $.coprocessorTxSenderAddresses[addCiphertextHash]
-            );
+            emit AddCiphertextMaterial(ctHandle, ciphertextDigest, snsCiphertextDigest, contextId);
         }
     }
 
@@ -205,13 +230,13 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
             // Get the unique hash associated to the handle and use it to get the list of coprocessor
             // transaction sender address that were involved in the consensus
             bytes32 addCiphertextHash = $.ctHandleConsensusHash[ctHandles[i]];
-            address[] memory coprocessorTxSenderAddresses = $.coprocessorTxSenderAddresses[addCiphertextHash];
 
             ctMaterials[i] = CiphertextMaterial(
                 ctHandles[i],
                 $.keyIds[ctHandles[i]],
                 $.ciphertextDigests[ctHandles[i]],
-                coprocessorTxSenderAddresses
+                $.coprocessorTxSenderAddresses[addCiphertextHash],
+                $.addCiphertextContextId[addCiphertextHash]
             );
         }
 
@@ -236,34 +261,40 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
             // Get the unique hash associated to the handle and use it to get the list of coprocessor
             // transaction sender address that were involved in the consensus
             bytes32 addCiphertextHash = $.ctHandleConsensusHash[ctHandles[i]];
-            address[] memory coprocessorTxSenderAddresses = $.coprocessorTxSenderAddresses[addCiphertextHash];
 
             snsCtMaterials[i] = SnsCiphertextMaterial(
                 ctHandles[i],
                 $.keyIds[ctHandles[i]],
                 $.snsCiphertextDigests[ctHandles[i]],
-                coprocessorTxSenderAddresses
+                $.coprocessorTxSenderAddresses[addCiphertextHash],
+                $.addCiphertextContextId[addCiphertextHash]
             );
         }
 
         return snsCtMaterials;
     }
 
     /**
-     * @notice See {ICiphertextCommits-getAddCiphertextMaterialConsensusTxSenders}.
-     * The list remains empty until the consensus is reached.
+     * @notice See {ICiphertextCommits-getConsensusCoprocessorTxSenders}.
+     * The list remains empty and the contextId is 0 until the consensus is reached.
      */
-    function getAddCiphertextMaterialConsensusTxSenders(
+    function getConsensusCoprocessorTxSenders(
         bytes32 ctHandle
-    ) external view virtual returns (address[] memory) {
+    ) external view virtual returns (address[] memory, uint256, bool) {
         CiphertextCommitsStorage storage $ = _getCiphertextCommitsStorage();
 
+        bool ciphertextMaterialAdded = $.isCiphertextMaterialAdded[ctHandle];
+
         // Get the unique hash associated to the handle in order to retrieve the list of transaction
         // sender address that participated in the consensus
         // This digest remains the default value (0x0) until the consensus is reached.
         bytes32 addCiphertextHash = $.ctHandleConsensusHash[ctHandle];
 
-        return $.coprocessorTxSenderAddresses[addCiphertextHash];
+        return (
+            $.coprocessorTxSenderAddresses[addCiphertextHash],
+            $.addCiphertextContextId[addCiphertextHash],
+            ciphertextMaterialAdded
+        );
     }
 
     /**
@@ -291,12 +322,13 @@ contract CiphertextCommits is ICiphertextCommits, UUPSUpgradeableEmptyProxy, Gat
     function _authorizeUpgrade(address _newImplementation) internal virtual override onlyGatewayOwner {}
 
     /**
-     * @notice Checks if the consensus is reached among the Coprocessors.
+     * @notice Checks if the consensus is reached among the coprocessors from the same context.
+     * @param contextId The coprocessor context ID
      * @param coprocessorCounter The number of coprocessors that agreed
      * @return Whether the consensus is reached
      */
-    function _isConsensusReached(uint256 coprocessorCounter) internal view virtual returns (bool) {
-        uint256 consensusThreshold = GATEWAY_CONFIG.getCoprocessorMajorityThreshold();
+    function _isConsensusReached(uint256 contextId, uint256 coprocessorCounter) internal view virtual returns (bool) {
+        uint256 consensusThreshold = COPROCESSOR_CONTEXTS.getCoprocessorMajorityThreshold(contextId);
         return coprocessorCounter >= consensusThreshold;
     }