add configurable gas limits and failure on calls

jayantk · jayantk · commit 52e680ac2b59 · 2025-03-28T10:17:48.000-07:00
diff --git a/target_chains/ethereum/contracts/contracts/entropy/Entropy.sol b/target_chains/ethereum/contracts/contracts/entropy/Entropy.sol
@@ -470,6 +470,15 @@ abstract contract Entropy is IEntropy, EntropyState {
         if (!req.isRequestWithCallback) {
             revert EntropyErrors.InvalidRevealCall();
         }
+        // Invariant check: all callback requests should have useBlockhash set to false.
+        if (req.useBlockhash) {
+            revert EntropyErrors.InvalidRevealCall();
+        }
+
+        if (req.reentryGuard) {
+            revert EntropyErrors.InvalidRevealCall();
+        }
+
         bytes32 blockHash;
         bytes32 randomNumber;
         (randomNumber, blockHash) = revealHelper(
@@ -480,27 +489,60 @@ abstract contract Entropy is IEntropy, EntropyState {
 
         address callAddress = req.requester;
 
-        emit RevealedWithCallback(
-            req,
-            userRandomNumber,
-            providerRevelation,
-            randomNumber
-        );
-
-        clearRequest(provider, sequenceNumber);
-
         // Check if the callAddress is a contract account.
+        // TODO: this can probably be deleted.
         uint len;
         assembly {
             len := extcodesize(callAddress)
         }
+
+        bool success;
+        bytes memory ret;
         if (len != 0) {
-            IEntropyConsumer(callAddress)._entropyCallback(
-                sequenceNumber,
-                provider,
+            uint64 gas;
+            if (req.blockNumber != 0) {
+                gas = req.blockNumber;
+            } else {
+                gas = gasLeft();
+            }
+
+            req.reentryGuard = true;
+            (success, ret) == callAddress.excessivelySafeCall(
+                gas,
+                32,
+                abi.encodeWithSelector(
+                    IEntropyConsumer._entropyCallback.selector,
+                    sequenceNumber,
+                    provider,
+                    randomNumber
+                )
+            );
+            req.reentryGuard = false;
+        }    
+
+        if (success) {
+            emit RevealedWithCallback(
+                req,
+                userRandomNumber,
+                providerRevelation,
                 randomNumber
             );
+            clearRequest(provider, sequenceNumber);
+        } else {
+            bytes32 errorReason;
+            assembly {
+                errorReason := mload(add(ret, 32));
+            }
+
+            emit CallbackFailed(
+                provider,
+                req.requester,
+                sequenceNumber,
+                errorReason
+            )
+            req.callbackAttempted = true;
         }
+
     }
 
     function getProviderInfo(
@@ -625,6 +667,24 @@ abstract contract Entropy is IEntropy, EntropyState {
         );
     }
 
+    // Set the default gas limit for a request.
+    function setDefaultGasLimit(uint64 gasLimit) external override {
+        EntropyStructs.ProviderInfo storage provider = _state.providers[
+            msg.sender
+        ];
+        if (provider.sequenceNumber == 0) {
+            revert EntropyErrors.NoSuchProvider();
+        }
+
+        uint64 oldGasLimit = provider.defaultGasLimit;
+        provider.defaultGasLimit = gasLimit;
+        emit ProviderDefaultGasLimitUpdated(
+            msg.sender,
+            oldGasLimit,
+            gasLimit
+        );
+    }
+
     function constructUserCommitment(
         bytes32 userRandomness
     ) public pure override returns (bytes32 userCommitment) {
diff --git a/target_chains/ethereum/contracts/package.json b/target_chains/ethereum/contracts/package.json
@@ -23,7 +23,7 @@
     "migrate": "truffle migrate",
     "receiver-submit-guardian-sets": "truffle exec scripts/receiverSubmitGuardianSetUpgrades.js",
     "verify": "truffle run verify $npm_config_module@$npm_config_contract_address --network $npm_config_network",
-    "install-forge-deps": "forge install foundry-rs/forge-std@v1.7.6 --no-git --no-commit",
+    "install-forge-deps": "forge install foundry-rs/forge-std@v1.7.6 nomad-xyz/ExcessivelySafeCall@81cd99c --no-git --no-commit",
     "coverage": "./coverage.sh",
     "test:format": "prettier --check .",
     "fix:format": "prettier --write ."
diff --git a/target_chains/ethereum/entropy_sdk/solidity/EntropyEvents.sol b/target_chains/ethereum/entropy_sdk/solidity/EntropyEvents.sol
@@ -28,6 +28,13 @@ interface EntropyEvents {
         bytes32 providerRevelation,
         bytes32 randomNumber
     );
+    // TODO: indexing, other fields??
+    event CallbackFailed(
+        address indexed provider,
+        address indexed requestor,
+        uint64 indexed sequenceNumber,
+        bytes32 errorCode
+    );
 
     event ProviderFeeUpdated(address provider, uint128 oldFee, uint128 newFee);
 
@@ -44,6 +51,12 @@ interface EntropyEvents {
         uint32 newMaxNumHashes
     );
 
+    event ProviderDefaultGasLimitUpdated(
+        address provider,
+        uint64 oldDefaultGasLimit,
+        uint64 newDefaultGasLimit
+    );
+
     event Withdrawal(
         address provider,
         address recipient,
diff --git a/target_chains/ethereum/entropy_sdk/solidity/EntropyStructs.sol b/target_chains/ethereum/entropy_sdk/solidity/EntropyStructs.sol
@@ -37,6 +37,8 @@ contract EntropyStructs {
         // Maximum number of hashes to record in a request. This should be set according to the maximum gas limit
         // the provider supports for callbacks.
         uint32 maxNumHashes;
+        // Default gas limit to use for callbacks.
+        uint64 defaultGasLimit;
     }
 
     struct Request {
@@ -54,13 +56,19 @@ contract EntropyStructs {
         // Note that we're using a uint64 such that we have an additional space for an address and other fields in
         // this storage slot. Although block.number returns a uint256, 64 bits should be plenty to index all of the
         // blocks ever generated.
+        //
+        // Note: We are overloading this storage slot to also store a gas limit for callbacks, as we do not support
+        // blockhashes in the callback case.
         uint64 blockNumber;
         // The address that requested this random number.
         address requester;
         // If true, incorporate the blockhash of blockNumber into the generated random value.
         bool useBlockhash;
         // If true, the requester will be called back with the generated random value.
         bool isRequestWithCallback;
-        // There are 2 remaining bytes of free space in this slot.
+        // If true, the callback has been attempted by the provider (and failed for some reason).
+        bool callbackAttempted;
+        // If true, a fulfillment request for this is already in-flight
+        bool reentryGuard;
     }
 }
diff --git a/target_chains/ethereum/entropy_sdk/solidity/abis/EntropyEvents.json b/target_chains/ethereum/entropy_sdk/solidity/abis/EntropyEvents.json
@@ -1,4 +1,60 @@
 [
+  {
+    "anonymous": false,
+    "inputs": [
+      {
+        "indexed": true,
+        "internalType": "address",
+        "name": "provider",
+        "type": "address"
+      },
+      {
+        "indexed": true,
+        "internalType": "address",
+        "name": "requestor",
+        "type": "address"
+      },
+      {
+        "indexed": true,
+        "internalType": "uint64",
+        "name": "sequenceNumber",
+        "type": "uint64"
+      },
+      {
+        "indexed": false,
+        "internalType": "bytes32",
+        "name": "errorCode",
+        "type": "bytes32"
+      }
+    ],
+    "name": "CallbackFailed",
+    "type": "event"
+  },
+  {
+    "anonymous": false,
+    "inputs": [
+      {
+        "indexed": false,
+        "internalType": "address",
+        "name": "provider",
+        "type": "address"
+      },
+      {
+        "indexed": false,
+        "internalType": "uint64",
+        "name": "oldDefaultGasLimit",
+        "type": "uint64"
+      },
+      {
+        "indexed": false,
+        "internalType": "uint64",
+        "name": "newDefaultGasLimit",
+        "type": "uint64"
+      }
+    ],
+    "name": "ProviderDefaultGasLimitUpdated",
+    "type": "event"
+  },
   {
     "anonymous": false,
     "inputs": [
@@ -163,6 +219,11 @@
             "internalType": "uint32",
             "name": "maxNumHashes",
             "type": "uint32"
+          },
+          {
+            "internalType": "uint64",
+            "name": "defaultGasLimit",
+            "type": "uint64"
           }
         ],
         "indexed": false,
@@ -218,6 +279,16 @@
             "internalType": "bool",
             "name": "isRequestWithCallback",
             "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "callbackAttempted",
+            "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "reentryGuard",
+            "type": "bool"
           }
         ],
         "indexed": false,
@@ -297,6 +368,16 @@
             "internalType": "bool",
             "name": "isRequestWithCallback",
             "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "callbackAttempted",
+            "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "reentryGuard",
+            "type": "bool"
           }
         ],
         "indexed": false,
@@ -352,6 +433,16 @@
             "internalType": "bool",
             "name": "isRequestWithCallback",
             "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "callbackAttempted",
+            "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "reentryGuard",
+            "type": "bool"
           }
         ],
         "indexed": false,
@@ -431,6 +522,16 @@
             "internalType": "bool",
             "name": "isRequestWithCallback",
             "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "callbackAttempted",
+            "type": "bool"
+          },
+          {
+            "internalType": "bool",
+            "name": "reentryGuard",
+            "type": "bool"
           }
         ],
         "indexed": false,
diff --git a/target_chains/ethereum/entropy_sdk/solidity/abis/IEntropy.json b/target_chains/ethereum/entropy_sdk/solidity/abis/IEntropy.json
