withdrawal.go

package common

import (
	"fmt"

	"github.com/MixinNetwork/mixin/config"
	"github.com/MixinNetwork/mixin/crypto"
)

type WithdrawalData struct {
	Address string
	Tag     string
}

func (tx *Transaction) validateWithdrawalSubmit(inputs map[string]*UTXO) error {
	for _, in := range inputs {
		if in.Type != OutputTypeScript {
			return fmt.Errorf("invalid utxo type %d", in.Type)
		}
	}
	for _, o := range tx.Outputs[1:] {
		if o.Type != OutputTypeScript {
			return fmt.Errorf("invalid change type %d for withdrawal submit transaction", tx.Outputs[1].Type)
		}
	}

	submit := tx.Outputs[0]
	if submit.Type != OutputTypeWithdrawalSubmit {
		return fmt.Errorf("invalid output type %d for withdrawal submit transaction", submit.Type)
	}
	if submit.Withdrawal == nil {
		return fmt.Errorf("invalid withdrawal submit data")
	}

	if len(submit.Keys) != 0 {
		return fmt.Errorf("invalid withdrawal submit keys %d", len(submit.Keys))
	}
	if len(submit.Script) != 0 {
		return fmt.Errorf("invalid withdrawal submit script %s", submit.Script)
	}
	if submit.Mask.HasValue() {
		return fmt.Errorf("invalid withdrawal submit mask %s", submit.Mask)
	}

	return nil
}

func (tx *Transaction) validateWithdrawalClaim(store DataStore, inputs map[string]*UTXO, snapTime uint64) error {
	for _, in := range inputs {
		if in.Type != OutputTypeScript {
			return fmt.Errorf("invalid utxo type %d", in.Type)
		}
	}

	if tx.Asset != XINAssetId {
		return fmt.Errorf("invalid asset %s for withdrawal claim transaction", tx.Asset)
	}
	for _, o := range tx.Outputs[1:] {
		if o.Type != OutputTypeScript {
			return fmt.Errorf("invalid change type %d for withdrawal claim transaction", tx.Outputs[1].Type)
		}
	}
	if len(tx.References) != 1 {
		return fmt.Errorf("invalid references count %d for withdrawal claim transaction", len(tx.References))
	}

	claim := tx.Outputs[0]
	if claim.Type != OutputTypeWithdrawalClaim {
		return fmt.Errorf("invalid output type %d for withdrawal claim transaction", claim.Type)
	}
	if claim.Amount.Cmp(NewIntegerFromString(config.WithdrawalClaimFee)) < 0 {
		return fmt.Errorf("invalid output amount %s for withdrawal claim transaction", claim.Amount)
	}

	submit, _, err := store.ReadTransaction(tx.References[0])
	if err != nil {
		return err
	}
	if submit == nil {
		return fmt.Errorf("invalid withdrawal submit data")
	}
	withdrawal := submit.Outputs[0].Withdrawal
	if withdrawal == nil || submit.Outputs[0].Type != OutputTypeWithdrawalSubmit {
		return fmt.Errorf("invalid withdrawal submit data")
	}

	var sig crypto.Signature
	if len(tx.Extra) < len(sig) {
		return fmt.Errorf("invalid withdrawal claim information")
	}
	copy(sig[:], tx.Extra[:len(sig)])
	eh := crypto.Blake3Hash(tx.Extra[len(sig):])
	cur, err := store.ReadCustodian(snapTime)
	if err != nil {
		return err
	}
	if !cur.Custodian.PublicSpendKey.Verify(eh, sig) {
		return fmt.Errorf("invalid custodian signature for withdrawal claim")
	}
	return nil
}