Bech32
Address format conversion between Ethereum hex addresses and Ontomir bech32 addresses
Address: 0x0000000000000000000000000000000000000400
Related Module: Address conversion utilities
The Bech32 precompile provides address format conversion functionality between Ethereum hex addresses and Ontomir bech32 addresses.
Overview
The Bech32 precompile exposes simple conversion helpers so Solidity contracts can:
Convert an Ethereum
addressto a Bech32 string with a desiredprefix(e.g.Ontomir).Convert any Bech32 address string back into an EVM
address.
It is a thin wrapper around the Ontomir address‐conversion library and lives at 0x0000000000000000000000000000000000000400.
Gas Costs
Both methods use a configurable base gas amount that is set during chain initialization. The gas cost is fixed regardless of string length within reasonable bounds.
Primary Methods
hexToBech32
hexToBech32Signature: hexToBech32(address addr, string memory prefix) → string memory
Description: Converts an Ethereum hex address to Ontomir bech32 format using the specified prefix.
```solidity Solidity expandable lines // SPDX-License-Identifier: MIT pragma solidity ^0.8.0;
// Interface for the Bech32 precompile interface IBech32 { function hexToBech32(address addr, string memory prefix) external returns (string memory bech32Address); function bech32ToHex(string memory bech32Address) external returns (address addr); }
contract Bech32Example { address constant BECH32_PRECOMPILE = 0x0000000000000000000000000000000000000400; IBech32 public immutable bech32; event AddressConverted(address indexed hexAddress, string bech32Address, string prefix); constructor() { bech32 = IBech32(BECH32_PRECOMPILE); } function hexToBech32(address addr, string calldata prefix) external returns (string memory bech32Address) { require(addr != address(0), "Invalid address"); require(bytes(prefix).length > 0, "Prefix cannot be empty"); bech32Address = bech32.hexToBech32(addr, prefix); emit AddressConverted(addr, bech32Address, prefix); return bech32Address; } // Convert multiple addresses with the same prefix function batchHexToBech32(address[] calldata addresses, string calldata prefix) external returns (string[] memory bech32Addresses) { bech32Addresses = new string; for (uint256 i = 0; i < addresses.length; i++) { require(addresses[i] != address(0), "Invalid address in batch"); bech32Addresses[i] = bech32.hexToBech32(addresses[i], prefix); emit AddressConverted(addresses[i], bech32Addresses[i], prefix); } return bech32Addresses; } // Get common address formats for a single hex address function getCommonFormats(address addr) external returns ( string memory OntomirAddr, string memory evmosAddr, string memory osmosisAddr ) { require(addr != address(0), "Invalid address"); OntomirAddr = bech32.hexToBech32(addr, "Ontomir"); evmosAddr = bech32.hexToBech32(addr, "evmos"); osmosisAddr = bech32.hexToBech32(addr, "osmo"); return (OntomirAddr, evmosAddr, osmosisAddr); } // Convert caller's address to bech32 format function getMyBech32Address(string calldata prefix) external returns (string memory) { return bech32.hexToBech32(msg.sender, prefix); }
}
```javascript Ethers.js expandable lines
import { ethers } from "ethers";
// Connect to the network
const provider = new ethers.JsonRpcProvider("<RPC_URL>");
// Precompile address and ABI
const precompileAddress = "0x0000000000000000000000000000000000000400";
const precompileAbi = [
"function hexToBech32(address addr, string memory prefix) returns (string memory)"
];
// Create a contract instance
const contract = new ethers.Contract(precompileAddress, precompileAbi, provider);
// Inputs
const ethAddress = "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"; // Placeholder
const prefix = "Ontomir";
async function convertToBech32() {
try {
const bech32Address = await contract.hexToBech32.staticCall(ethAddress, prefix);
console.log("Bech32 Address:", bech32Address);
} catch (error) {
console.error("Error converting to Bech32:", error);
}
}
convertToBech32();# Replace <RPC_URL> with your actual RPC endpoint.
# The address and prefix are placeholders.
curl -X POST --data '{
"jsonrpc": "2.0",
"method": "eth_call",
"params": [
{
"to": "0x0000000000000000000000000000000000000400",
"data": "0xf958a98c000000000000000000000000d8da6bf26964af9d7eed9e03e53415d37aa9604500000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000006636f736d6f730000000000000000000000000000000000000000000000000000"
},
"latest"
],
"id": 1
}' -H "Content-Type: application/json" <RPC_URL>Parameters:
addr(address): The Ethereum hex address to convertprefix(string): The bech32 prefix to use (e.g., "Ontomir")
Returns: String containing the bech32 formatted address
bech32ToHex
bech32ToHexSignature: bech32ToHex(string memory bech32Address) → address
Description: Converts a Ontomir bech32 address to Ethereum hex format.
```solidity Solidity expandable lines // SPDX-License-Identifier: MIT pragma solidity ^0.8.0;
// Interface for the Bech32 precompile interface IBech32 { function bech32ToHex(string memory bech32Address) external returns (address addr); function hexToBech32(address addr, string memory prefix) external returns (string memory bech32Address); }
contract Bech32Example { address constant BECH32_PRECOMPILE = 0x0000000000000000000000000000000000000400; IBech32 public immutable bech32; event Bech32Converted(string bech32Address, address indexed hexAddress); constructor() { bech32 = IBech32(BECH32_PRECOMPILE); } function bech32ToHex(string calldata bech32Address) external returns (address hexAddress) { require(bytes(bech32Address).length > 0, "Bech32 address cannot be empty"); hexAddress = bech32.bech32ToHex(bech32Address); require(hexAddress != address(0), "Invalid bech32 address"); emit Bech32Converted(bech32Address, hexAddress); return hexAddress; } // Convert multiple bech32 addresses to hex format function batchBech32ToHex(string[] calldata bech32Addresses) external returns (address[] memory hexAddresses) { hexAddresses = new address; for (uint256 i = 0; i < bech32Addresses.length; i++) { require(bytes(bech32Addresses[i]).length > 0, "Invalid bech32 address"); hexAddresses[i] = bech32.bech32ToHex(bech32Addresses[i]); require(hexAddresses[i] != address(0), "Invalid bech32 address in batch"); emit Bech32Converted(bech32Addresses[i], hexAddresses[i]); } return hexAddresses; } // Validate address conversion by converting back and forth function validateAddressConversion(address addr, string calldata prefix) external returns (bool isValid) { try bech32.hexToBech32(addr, prefix) returns (string memory bech32Addr) { try bech32.bech32ToHex(bech32Addr) returns (address convertedBack) { isValid = (convertedBack == addr); return isValid; } catch { return false; } } catch { return false; } } // Check if two addresses (hex and bech32) represent the same account function areAddressesEqual(address hexAddr, string calldata bech32Addr) external returns (bool isEqual) { try bech32.bech32ToHex(bech32Addr) returns (address convertedHex) { isEqual = (convertedHex == hexAddr); return isEqual; } catch { return false; } } // Safely convert bech32 to hex with error handling function safeBech32ToHex(string calldata bech32Address) external returns (bool success, address hexAddress) { try bech32.bech32ToHex(bech32Address) returns (address addr) { return (true, addr); } catch { return (false, address(0)); } }
}
```javascript Ethers.js expandable lines
import { ethers } from "ethers";
// Connect to the network
const provider = new ethers.JsonRpcProvider("<RPC_URL>");
// Precompile address and ABI
const precompileAddress = "0x0000000000000000000000000000000000000400";
const precompileAbi = [
"function bech32ToHex(string memory bech32Address) returns (address)"
];
// Create a contract instance
const contract = new ethers.Contract(precompileAddress, precompileAbi, provider);
// Input
const bech32Address = "Ontomir1mrdxhunfvjhe6lhdncp72dq46da2jcz9d9sh93"; // Placeholder
async function convertToHex() {
try {
const hexAddress = await contract.bech32ToHex.staticCall(bech32Address);
console.log("Hex Address:", hexAddress);
} catch (error) {
console.error("Error converting to Hex:", error);
}
}
convertToHex();# Replace <RPC_URL> with your actual RPC endpoint.
# The address is a placeholder.
curl -X POST --data '{
"jsonrpc": "2.0",
"method": "eth_call",
"params": [
{
"to": "0x0000000000000000000000000000000000000400",
"data": "0xe6df461e0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002a636f736d6f733171716c38616734636c757a367234647a32327064656e726d776c6975667173733863396a306500000000000000000000000000000000000000"
},
"latest"
],
"id": 1
}' -H "Content-Type: application/json" <RPC_URL>Parameters:
bech32Address(string): The bech32 formatted address to convert
Returns: Ethereum address in hex format
Full Interface & ABI
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.8.17;
/// @dev The Bech32I contract's address.
address constant Bech32_PRECOMPILE_ADDRESS = 0x0000000000000000000000000000000000000400;
/// @dev The Bech32I contract's instance.
Bech32I constant BECH32_CONTRACT = Bech32I(Bech32_PRECOMPILE_ADDRESS);
interface Bech32I {
function hexToBech32(address addr,string memory prefix) external returns (string memory bech32Address);
function bech32ToHex(string memory bech32Address) external returns (address addr);
}{
"_format": "hh-sol-artifact-1",
"contractName": "Bech32I",
"sourceName": "solidity/precompiles/bech32/Bech32I.sol",
"abi": [
{
"inputs": [
{
"internalType": "string",
"name": "bech32Address",
"type": "string"
}
],
"name": "bech32ToHex",
"outputs": [
{
"internalType": "address",
"name": "addr",
"type": "address"
}
],
"stateMutability": "nonpayable",
"type": "function"
},
{
"inputs": [
{
"internalType": "address",
"name": "addr",
"type": "address"
},
{
"internalType": "string",
"name": "prefix",
"type": "string"
}
],
"name": "hexToBech32",
"outputs": [
{
"internalType": "string",
"name": "bech32Address",
"type": "string"
}
],
"stateMutability": "nonpayable",
"type": "function"
}
],
"bytecode": "0x",
"deployedBytecode": "0x",
"linkReferences": {},
"deployedLinkReferences": {}
}Implementation Details
Address Validation
Both methods perform validation on the address format:
hexToBech32: Validates that the hex address is exactly 20 bytes and the prefix is non-empty
bech32ToHex: Validates that the bech32 address contains the separator character "1" and decodes to 20 bytes
Prefix Handling
For hexToBech32:
The prefix parameter determines the human-readable part of the bech32 address
Common prefixes include account addresses, validator addresses, and consensus addresses
Empty or whitespace-only prefixes result in an error with suggested valid prefixes
For bech32ToHex:
The prefix is automatically extracted from the bech32 address
No prefix parameter is required as it's embedded in the address
State Mutability
While both methods are marked as nonpayable in the ABI, they function as read-only operations and do not modify blockchain state.
