Multi-Signature Splits Contract

This Soroban smart contract implements multi-signature functionality with time-locks for large splits in the StellarSplit application.

Overview

The contract enables secure handling of high-value splits by requiring multiple signatures and enforcing time delays before execution. This provides additional security layers for large transactions.

Features

• Multi-signature Requirements: Configurable number of signatures needed
• Time Locks: Enforceable delays before execution
• Signature Collection: Track and validate participant approvals
• Cancellation Mechanism: Admin can cancel splits when necessary
• Emergency Override: Admin can execute splits immediately in emergencies

Functions

initialize(env: Env, admin: Address)

Initializes the contract with an admin address. Must be called before any other operations.

create_multisig_split(env: Env, split_id: String, required_sigs: u32, time_lock: u64) -> Result<(), MultisigError>

Creates a new multi-signature split with the specified parameters:

• split_id: Unique identifier for the split
• required_sigs: Number of signatures required (minimum 1)
• time_lock: Time delay in seconds before execution is allowed

sign_split(env: Env, split_id: String, signer: Address) -> Result<bool, MultisigError>

Allows a signer to add their signature to a split. Returns true if the split can now be executed.

execute_split(env: Env, split_id: String) -> Result<(), MultisigError>

Executes a split once all required signatures are collected and the time lock has expired.

cancel_split(env: Env, split_id: String, reason: String) -> Result<(), MultisigError>

Allows the admin to cancel a split with a reason. Only the admin can perform this action.

emergency_override(env: Env, split_id: String) -> Result<(), MultisigError>

Allows the admin to execute a split immediately, bypassing signature and time lock requirements.

get_split_info(env: Env, split_id: String) -> MultisigSplit

Returns detailed information about a split including current status and signatures.

can_execute_split(env: Env, split_id: String) -> bool

Checks if a split can be executed (all signatures collected and time lock expired).

Split States

• Pending: Created but no signatures yet
• Active: At least one signature collected
• Executed: Successfully executed
• Cancelled: Cancelled by admin
• Expired: Time lock expired without execution

Error Types

• SplitAlreadyExists: Split ID already in use
• SplitNotFound: Split does not exist
• InvalidThreshold: Invalid signature threshold or time lock
• AlreadySigned: Signer has already signed this split
• NotAuthorized: Operation not authorized
• TimeLockNotExpired: Time lock has not expired yet
• InsufficientSignatures: Not enough signatures collected
• SplitNotActive: Split is not in active state
• SplitAlreadyExecuted: Split already executed or cancelled

Building

cd contracts/multi-sig-splits
cargo build --target wasm32-unknown-unknown --release

Testing

cd contracts/multi-sig-splits
cargo test

Security Considerations

• Only the admin can cancel splits or perform emergency overrides
• Time locks prevent rushed executions
• Duplicate signatures are prevented
• All state changes emit events for tracking

Integration

This contract should be integrated with the main split escrow contract to provide enhanced security for high-value transactions. The split creation process should check transaction amounts and automatically use multi-sig for large values.