parseCompactSignature

Parses a hex formatted compact signature (EIP-2098) into a structured CompactSignature with R and YParityAndS components.

Import

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

Usage

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

sig, err := signature.ParseCompactSignature(
  "0x68a020a209d3d56c46f38cc50a33f704f4a9a10a59377f8dd762ac66910e9b907e865ad05c4035ab5792787d4a0297a43617ae897930a6fe4d822b8faea52064",
)
if err != nil {
  log.Fatal(err)
}

fmt.Printf("R: %s
", sig.R)
// R: 0x68a020a209d3d56c46f38cc50a33f704f4a9a10a59377f8dd762ac66910e9b90

fmt.Printf("YParityAndS: %s
", sig.YParityAndS)
// YParityAndS: 0x7e865ad05c4035ab5792787d4a0297a43617ae897930a6fe4d822b8faea52064

Returns

• Type: (*signature.CompactSignature, error)

A structured compact signature with R and YParityAndS fields.

Parameters

signatureHex (required)

• Type: string

The hex formatted compact signature string. Must be 64 bytes (128 hex characters with 0x prefix).

sig, _ := signature.ParseCompactSignature(
  "0x68a020a209d3d56c46f38cc50a33f704f4a9a10a59377f8dd762ac66910e9b907e865ad05c4035ab5792787d4a0297a43617ae897930a6fe4d822b8faea52064",
)

Compact Signature Structure

The parsed compact signature contains:

• R: The R component (32 bytes as hex string)
• YParityAndS: The S component with yParity encoded in the top bit of the first byte (32 bytes as hex string)

Functions

ParseCompactSignature

Parses a hex compact signature string:

sig, _ := signature.ParseCompactSignature("0x68a020a209d3d56c46f38cc50a33f704f4a9a10a59377f8dd762ac66910e9b907e865ad05c4035ab5792787d4a0297a43617ae897930a6fe4d822b8faea52064")

ParseCompactSignatureBytes

Parses a 64-byte compact signature:

sig, _ := signature.ParseCompactSignatureBytes([]byte{0x68, 0xa0, ...})

Compact Signature Format (EIP-2098)

The compact signature format is:

• First 32 bytes: R component
• Next 32 bytes: S component with yParity encoded in the top bit (bit 7) of the first byte
  • If bit 7 is set, yParity = 1
  • If bit 7 is clear, yParity = 0

This reduces the signature size from 65 bytes to 64 bytes.