fix: ledger signature verification fallback

nayms · May 12, 2023 · f8b7766 · f8b7766
1 parent eec4700
commit f8b7766
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Showing 2 changed files with 46 additions and 10 deletions.
diff --git a/src/diamonds/nayms/libs/LibEntity.sol b/src/diamonds/nayms/libs/LibEntity.sol
@@ -143,13 +143,18 @@ library LibEntity {
             }
 
             if (LibObject._getParentFromAddress(signer) != _stakeholders.entityIds[i]) {
-                revert SimplePolicyStakeholderSignatureInvalid(
-                    signingHash,
-                    _stakeholders.signatures[i],
-                    LibHelpers._getIdForAddress(signer),
-                    LibObject._getParentFromAddress(signer),
-                    _stakeholders.entityIds[i]
-                );
+                // default implementation didn't match the signer
+                signer = getSignerLedgerFallback(signingHash, _stakeholders.signatures[i]); // fallback ledger implementation
+
+                if (LibObject._getParentFromAddress(signer) != _stakeholders.entityIds[i]) {
+                    revert SimplePolicyStakeholderSignatureInvalid(
+                        signingHash,
+                        _stakeholders.signatures[i],
+                        LibHelpers._getIdForAddress(signer),
+                        LibObject._getParentFromAddress(signer),
+                        _stakeholders.entityIds[i]
+                    );
+                }
             }
             LibACL._assignRole(_stakeholders.entityIds[i], _policyId, _stakeholders.roles[i]);
         }
@@ -158,6 +163,38 @@ library LibEntity {
         emit SimplePolicyCreated(_policyId, _entityId);
     }
 
+    function getSignerLedgerFallback(bytes32 signingHash, bytes memory signature) private returns (address) {
+        bytes32 r;
+        bytes32 s;
+        uint8 v;
+
+        // ecrecover takes the signature parameters, and the only way to get them
+        if (signature.length == 65) {
+            // currently is to use assembly.
+            /// @solidity memory-safe-assembly
+            assembly {
+                r := mload(add(signature, 0x20))
+                s := mload(add(signature, 0x40))
+                v := byte(0, mload(add(signature, 0x60)))
+            }
+            v = _adjustV(v);
+        }
+
+        (address signer, ) = ECDSA.tryRecover(ECDSA.toEthSignedMessageHash(signingHash), v, r, s);
+
+        return signer;
+    }
+
+    function _adjustV(uint8 v) private returns (uint8) {
+        if (v == 0) {
+            return 27;
+        } else if (v == 1) {
+            return 28;
+        } else {
+            return v;
+        }
+    }
+
     /// @param _amount the amount of entity token that is minted and put on sale
     /// @param _totalPrice the buy amount
     function _startTokenSale(

diff --git a/test/T05TokenWrapper.t.sol b/test/T05TokenWrapper.t.sol
@@ -100,19 +100,18 @@ contract T05TokenWrapper is D03ProtocolDefaults {
         vm.startPrank(signer1);
         wrapper.increaseAllowance(account0, type(uint256).max);
         assertEq(wrapper.allowance(signer1, account0), type(uint256).max, "allowance should have increased");
-        
+
         vm.expectRevert("ERC20: allowance overflow");
         wrapper.increaseAllowance(account0, 1);
         vm.stopPrank();
 
         vm.startPrank(signer1);
         wrapper.decreaseAllowance(account0, type(uint256).max);
         assertEq(wrapper.allowance(signer1, account0), 0, "allowance should have decreased");
-        
+
         vm.expectRevert("ERC20: decreased allowance below zero");
         wrapper.decreaseAllowance(account0, 1);
         vm.stopPrank();
-
     }
 
     function testPermit() public {