labelhash

Computes the keccak256 hash of an ENS label.

:::warning[Warning] ENS labels prohibit certain forbidden characters (e.g. underscore) and have other validation rules. You likely want to normalize ENS labels with UTS-46 normalization before passing them to labelhash. You can use the Normalize function for this. :::

Import

import "github.com/ChefBingbong/viem-go/utils/ens"

Usage

import "github.com/ChefBingbong/viem-go/utils/ens"

// Compute labelhash
hash := ens.Labelhash("eth")
// "0x4f5b812789fc606be1b3b16908db13fc7a9adf7ca72641f84d75b47069d3d7f0"

hash = ens.Labelhash("vitalik")
// "0xaf2caa1c2ca1d027f1ac823b529d0a67cd144264b2789fa2ea4d63a67c7103cc"

// Get labelhash as bytes
hashBytes := ens.LabelhashBytes("eth")
// []byte{...}

Returns

• Type: string for Labelhash, []byte for LabelhashBytes

The labelhash as a hex string with 0x prefix (32 bytes) or raw bytes.

Parameters

label (required)

• Type: string

The ENS label to compute the labelhash for. Should be normalized before hashing.

// Normalize first (recommended)
normalized, _ := ens.Normalize("ETH")
hash := ens.Labelhash(normalized)
// "0x4f5b812789fc606be1b3b16908db13fc7a9adf7ca72641f84d75b47069d3d7f0"

// Direct labelhash (if already normalized)
hash = ens.Labelhash("eth")

Algorithm

The labelhash algorithm:

1. If the label is empty, returns 32 zero bytes
2. If the label is an encoded labelhash (format: [<64 hex chars>]), extracts and returns it
3. Otherwise, computes keccak256 of the label bytes
4. Returns the 32-byte hash

Functions

Labelhash

Computes labelhash and returns a hex string:

hash := ens.Labelhash("eth")

LabelhashBytes

Computes labelhash and returns raw bytes:

hashBytes := ens.LabelhashBytes("eth")

Notes

• Empty label returns 32 zero bytes
• Handles encoded labelhashes (format: [<64 hex chars>])
• Used internally by Namehash to hash individual labels
• Should normalize labels before hashing to ensure consistency