Unified request validator (#247)

* Extract ValidatePush, ValidatePull

* Add unified request validator

* Remove ClientRequestValidator, ProviderRequestValidator in favor of the unified one

storagemarket/impl/requestvalidation/client_request_validator.go → storagemarket/impl/requestvalidation/common.go

@@ -11,32 +11,42 @@ import (
 	"github.com/filecoin-project/go-fil-markets/storagemarket"
 )
 
-var _ datatransfer.RequestValidator = &ClientRequestValidator{}
-
-// ClientRequestValidator validates data transfer requests for the client
-// in a storage market
-type ClientRequestValidator struct {
-	deals *statestore.StateStore
-}
-
-// NewClientRequestValidator returns a new client request validator for the
-// given datastore
-func NewClientRequestValidator(deals *statestore.StateStore) *ClientRequestValidator {
-	crv := &ClientRequestValidator{
-		deals: deals,
-	}
-	return crv
-}
-
 // ValidatePush validates a push request received from the peer that will send data
-// Will always error because clients should not accept push requests from a provider
-// in a storage deal (i.e. send data to client).
-func (c *ClientRequestValidator) ValidatePush(
+// Will succeed only if:
+// - voucher has correct type
+// - voucher references an active deal
+// - referenced deal matches the client
+// - referenced deal matches the given base CID
+// - referenced deal is in an acceptable state
+func ValidatePush(
+	deals *statestore.StateStore,
 	sender peer.ID,
 	voucher datatransfer.Voucher,
 	baseCid cid.Cid,
 	Selector ipld.Node) error {
-	return ErrNoPushAccepted
+	dealVoucher, ok := voucher.(*StorageDataTransferVoucher)
+	if !ok {
+		return xerrors.Errorf("voucher type %s: %w", voucher.Type(), ErrWrongVoucherType)
+	}
+
+	var deal storagemarket.MinerDeal
+	err := deals.Get(dealVoucher.Proposal).Get(&deal)
+	if err != nil {
+		return xerrors.Errorf("Proposal CID %s: %w", dealVoucher.Proposal.String(), ErrNoDeal)
+	}
+	if deal.Client != sender {
+		return xerrors.Errorf("Deal Peer %s, Data Transfer Peer %s: %w", deal.Client.String(), sender.String(), ErrWrongPeer)
+	}
+
+	if !deal.Ref.Root.Equals(baseCid) {
+		return xerrors.Errorf("Deal Payload CID %s, Data Transfer CID %s: %w", deal.Proposal.PieceCID.String(), baseCid.String(), ErrWrongPiece)
+	}
+	for _, state := range DataTransferStates {
+		if deal.State == state {
+			return nil
+		}
+	}
+	return xerrors.Errorf("Deal State %s: %w", deal.State, ErrInacceptableDealState)
 }
 
 // ValidatePull validates a pull request received from the peer that will receive data
@@ -46,7 +56,8 @@ func (c *ClientRequestValidator) ValidatePush(
 // - referenced deal matches the receiver (miner)
 // - referenced deal matches the given base CID
 // - referenced deal is in an acceptable state
-func (c *ClientRequestValidator) ValidatePull(
+func ValidatePull(
+	deals *statestore.StateStore,
 	receiver peer.ID,
 	voucher datatransfer.Voucher,
 	baseCid cid.Cid,
@@ -57,7 +68,7 @@ func (c *ClientRequestValidator) ValidatePull(
 	}
 
 	var deal storagemarket.ClientDeal
-	err := c.deals.Get(dealVoucher.Proposal).Get(&deal)
+	err := deals.Get(dealVoucher.Proposal).Get(&deal)
 	if err != nil {
 		return xerrors.Errorf("Proposal CID %s: %w", dealVoucher.Proposal.String(), ErrNoDeal)
 	}