All Questions
Tagged with delegatecall contract-development
24 questions
0
votes
1
answer
162
views
Delegatecall failing 'could not coalesce error'
I'm trying to set a message to my Contract setmsg through a proxy contract using delegatecall.Using hardhat.
getting this error:
error: {
code: -32603,
message: "Error: VM Exception ...
0
votes
1
answer
39
views
How to build a 3 contract structure with delegatecall
I'm looking for help to build an intermediate contract using delegatecall. My challenge would be with 3 contracts.
I need contract A to be the owner of Contract B, and contract B to have a ...
1
vote
1
answer
191
views
Does delegatecall also works for calling other contract's constructor?
I want to call other contract's constructor, but I'm not sure if the delegatecall function will work for that case. I have no way to test it out on Remix, because my Remix seem to not work with even ...
- 23
0
votes
1
answer
85
views
How call() function works in solidity?
Learning call() function in Solidity, I read that we use call() only when we don't know the ABI of the called contract and we don't know its source code.
Below I have an example, but it seems we DO ...
- 75
0
votes
0
answers
244
views
EOA delegating call authority to a contract to interact with another contract
Actually, I want my contract (say A) to interact with a project's contract (say B).
But, contract B's author has restricted calls by any contract. So with this, only one option is left i.e. an EOA ...
- 219
0
votes
1
answer
835
views
delegateCall in Solidity understanding case
pragma solidity ^0.8.10;
/*
HackMe is a contract that uses delegatecall to execute code.
It it is not obvious that the owner of HackMe can be changed since there is no
function inside HackMe to do so....
- 3
0
votes
2
answers
65
views
Wrong address rertun when I call ownerof with delegatecall
I am trying to call the function "ownerof" of a contract but it return me something like that : ...
- 11
1
vote
0
answers
223
views
How to manually generate calldata
Here's my code snippet:
function getCalldata(string calldata _func, string calldata _param1, uint256 _param2) public pure returns (bytes memory) {
return abi.encodeWithSignature(_func, _param1,...
- 31
0
votes
0
answers
265
views
How does DELEGATECALL behave when calling other contracts?
I am trying to make a Parent-Contract which has a function which spends ERC-20 Tokens. I want to call this function from different Child-Contracts (which are deployed independently) using Delegatecall....
- 35
0
votes
0
answers
46
views
Does delegatecall() use only the calling function?
Let me explain with the code:
contract A {
function f() public {
[...]
g();
}
function g() private {
[...]
}
}
contract B {
A a;
function delegateA() public {
(bool success, ) = address(...
- 1
2
votes
1
answer
41
views
Am I locked to one solc version for upgradeable smart contracts?
I want to use delegatecall to make my contracts upgradeable.
Is it true that variable layout may break if I change the solc version and therefore I should use the same Solidity version for all future ...
- 1,854
1
vote
0
answers
94
views
How dangerous is this: number of contracts contain a function like "approveandcall" which lets anyone call any contract (some thoughts?)
The most common implementation is as follows:
function approveAndCall(address _spender, uint256 _value, bytes _extraData) public returns (bool success) {
tokenRecipient spender = tokenRecipient(...
- 479
12
votes
2
answers
2k
views
Pros and Cons of smart contract upgradable patterns
There have been quite many arguments around how to achieve smart contract updates like Upgradeable smart contracts.
I feel Proxycontract with Delegate-call is currently the most famous one. But aside ...
- 467
3
votes
0
answers
705
views
Anything like a static delegatecall from a view function?
let's say there are two contracts A and B, where A calls methods in B. I understand that A can modify and read storage in B with B.call() and B.staticcall(), ie. A can execute B's methods in the ...
- 861
0
votes
2
answers
967
views
How to use Role-Based Access Control via Proxy?
I have a PermissionsManager contract that uses OpenZeppelin's Role-Based Access Control (RBAC) template as a base. Currently function modifiers in my app call PermissionsManager directly to check for ...
- 113
2
votes
1
answer
237
views
How does a contract know which library to query or know the library address?
How does a contract know which library to query? For Example in the code below (The code is from solidity docs: https://solidity.readthedocs.io/en/v0.4.24/contracts.html?highlight=library#libraries
...
- 1,853
3
votes
2
answers
2k
views
Double delegate call doesn't work
To create an upgradeable contract I have to use multiple proxies. The contract applies to Proxy A, then Proxy A applies to Proxy B. But delegatecall doesn't work in this case.
The simplified code of ...
- 195
1
vote
1
answer
1k
views
Solidity - selfdestruct
I'm just wondering what would happen if I don't put a selfdestrut() method in my smart contract.
As I read from the Solidity documentation (Self-destruct):
Even if a contract’s code does not ...
- 101
2
votes
2
answers
3k
views
Warning: The use of low level "call" should be avoided whenever possible
I am writing my own smart contract and I want to call a function from a contract that has already been deployed. The fragment of my code:
function myFunc(address _contractAddress, address _user, uint ...
- 256
3
votes
2
answers
2k
views
Is it possible to copy the internal storage of a smart contract to a new contract?
Assume that I want to implement my own version of a suicide contract function with extended functionality. More specifically, I want to copy the internal storage state of the contract to a new ...
- 131
5
votes
2
answers
1k
views
How to make function call through relay / entry level contract
I am trying to create an entry level contract (one that is the entry point):
Relay.sol
pragma solidity ^0.4.8;
contract Relay {
address public currentVersion;
address public owner;
...
- 763
3
votes
2
answers
350
views
Get return value of Contract using CALL method
I have a contract which has such field:
mapping (address => int) balance;
It will hold the balance of account for coins. Let's assume that I've deployed this contract, but I want to disable ...
- 31
2
votes
0
answers
471
views
Simpler examples of contract versioning [closed]
I want to have an upgradable contract so that I can have additional functionalities in upgraded contract. I know there are numerous of questions around it, most of them pointing towards Upgradable ...
- 8,076
1
vote
1
answer
137
views
Help me debug this delegatecall Serpent demo I'm working on?
https://gist.github.com/ChrisCalderon/2818e6ba0214c25962b16c02e761dc26
Whenever I try to run it, I get "Transaction Failed". What it's supposed to do is call it's own functions double and half using ...
- 695