AW-Tool Sign EdDSA Documentation

The aw-tool-sign-eddsa package provides functionality for performing EdDSA signing operations using Lit Protocol's PKPs (Programmable Key Pairs). This tool enables secure signing of arbitrary messages while enforcing policy-based controls.

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Files Overview (in src/lib)

$3

Contains the main logic for executing a Lit Action to perform EdDSA signing operations.

#### Key Features:
- PKP Info Retrieval: Fetches PKP details and validates the tool policy
- Policy Validation: Checks if a policy exists and executes it if present
- Message Signing: Signs messages using EdDSA (Ed25519) via Lit Actions
- Error Handling: Comprehensive error handling with detailed responses

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$3

Defines and validates the EdDSA signing policy.

#### Key Features:
- Policy Validation: Validates policy parameters including:
- Allowed message prefixes
- Message size limits
- Message Validation: Ensures messages match allowed patterns
- Type Safety: Uses strong typing for policy parameters

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$3

Collection of utility functions for the signing process:

#### Key Components:
- solana-keypair.ts: Handles Solana keypair creation and management
- sign-message.ts: Core message signing functionality
- index.ts: Exports utility functions

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Usage

The tool requires the following parameters:
``typescript
{
pkpEthAddress: string; // PKP's Ethereum address
message: string; // Message to be signed
ciphertext: string; // Encrypted private key data
dataToEncryptHash: string; // Hash of the encrypted data
}
`

$3

The tool supports policy restrictions on:
- Allowed message prefixes
- Message content validation
- Signing frequency limits

$3

Success Response:
`typescript
{
status: 'success',
signature: string, // Base64-encoded signature
publicKey: string // Base58-encoded public key
}
`

Error Response:
`typescript
{
status: 'error',
error: string,
details: {
message: string,
type: string,
stack?: string
}
}
`

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Security Features

1. Policy Enforcement: Validates all signing operations against defined policies
2. Access Control: Uses Lit Protocol's access control conditions
3. Secure Key Management: Handles private keys securely through encryption
4. Message Validation: Enforces message format and content restrictions

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Dependencies

- @solana/web3.js: Solana blockchain interaction
- @lit-protocol/aw-tool: Core Agent Wallet tooling
- tweetnacl`: For Ed25519 signature verification