// validUnconfirmedTransaction checks that the transaction would be valid in a
// block that contained all of the other unconfirmed transactions.
func (tp *TransactionPool) validUnconfirmedTransaction(t types.Transaction) (err error) {
// Check that the transaction follows 'Standard.md' guidelines.
err = tp.IsStandardTransaction(t)
if err != nil {
return
}
// StandaloneValid will check things like signatures and properties that
// should be inherent to the transaction. (storage proof rules, etc.)
err = t.StandaloneValid(tp.consensusSetHeight)
if err != nil {
return
}
// Check the validity of the componenets in the context of the confirmed
// and unconfirmed set.
err = tp.validUnconfirmedSiacoins(t)
if err != nil {
return
}
err = tp.validUnconfirmedStorageProofs(t)
if err != nil {
return
}
err = tp.validUnconfirmedFileContractRevisions(t)
if err != nil {
return
}
err = tp.validUnconfirmedSiafunds(t)
if err != nil {
return
}
return
}
// validTransaction checks that all fields are valid within the current
// consensus state. If not an error is returned.
func validTransaction(tx *bolt.Tx, t types.Transaction) error {
// StandaloneValid will check things like signatures and properties that
// should be inherent to the transaction. (storage proof rules, etc.)
err := t.StandaloneValid(blockHeight(tx))
if err != nil {
return err
}
// Check that each portion of the transaction is legal given the current
// consensus set.
err = validSiacoins(tx, t)
if err != nil {
return err
}
err = validStorageProofs(tx, t)
if err != nil {
return err
}
err = validFileContractRevisions(tx, t)
if err != nil {
return err
}
err = validSiafunds(tx, t)
if err != nil {
return err
}
return nil
}
// negotiateRevision sends a revision and actions to the host for approval,
// completing one iteration of the revision loop.
func negotiateRevision(conn net.Conn, rev types.FileContractRevision, secretKey crypto.SecretKey) (types.Transaction, error) {
// create transaction containing the revision
signedTxn := types.Transaction{
FileContractRevisions: []types.FileContractRevision{rev},
TransactionSignatures: []types.TransactionSignature{{
ParentID: crypto.Hash(rev.ParentID),
CoveredFields: types.CoveredFields{FileContractRevisions: []uint64{0}},
PublicKeyIndex: 0, // renter key is always first -- see formContract
}},
}
// sign the transaction
encodedSig, _ := crypto.SignHash(signedTxn.SigHash(0), secretKey) // no error possible
signedTxn.TransactionSignatures[0].Signature = encodedSig[:]
// send the revision
if err := encoding.WriteObject(conn, rev); err != nil {
return types.Transaction{}, errors.New("couldn't send revision: " + err.Error())
}
// read acceptance
if err := modules.ReadNegotiationAcceptance(conn); err != nil {
return types.Transaction{}, errors.New("host did not accept revision: " + err.Error())
}
// send the new transaction signature
if err := encoding.WriteObject(conn, signedTxn.TransactionSignatures[0]); err != nil {
return types.Transaction{}, errors.New("couldn't send transaction signature: " + err.Error())
}
// read the host's acceptance and transaction signature
// NOTE: if the host sends ErrStopResponse, we should continue processing
// the revision, but return the error anyway.
responseErr := modules.ReadNegotiationAcceptance(conn)
if responseErr != nil && responseErr != modules.ErrStopResponse {
return types.Transaction{}, errors.New("host did not accept transaction signature: " + responseErr.Error())
}
var hostSig types.TransactionSignature
if err := encoding.ReadObject(conn, &hostSig, 16e3); err != nil {
return types.Transaction{}, errors.New("couldn't read host's signature: " + err.Error())
}
// add the signature to the transaction and verify it
// NOTE: we can fake the blockheight here because it doesn't affect
// verification; it just needs to be above the fork height and below the
// contract expiration (which was checked earlier).
verificationHeight := rev.NewWindowStart - 1
signedTxn.TransactionSignatures = append(signedTxn.TransactionSignatures, hostSig)
if err := signedTxn.StandaloneValid(verificationHeight); err != nil {
return types.Transaction{}, err
}
// if the host sent ErrStopResponse, return it
return signedTxn, responseErr
}
// verifyKeysSiag_1_0 is a copy-pasted version of the verifyKeys method
// from siag 1.0.
func verifyKeysSiag_1_0(uc types.UnlockConditions, folder string, keyname string) error {
keysRequired := uc.SignaturesRequired
totalKeys := uint64(len(uc.PublicKeys))
loadedKeys := make([]KeyPairSiag_1_0, totalKeys)
for i := 0; i < len(loadedKeys); i++ {
err := encoding.ReadFile(filepath.Join(folder, keyname+"_Key"+strconv.Itoa(i)+".siakey"), &loadedKeys[i])
if err != nil {
return err
}
}
for _, loadedKey := range loadedKeys {
if loadedKey.UnlockConditions.UnlockHash() != uc.UnlockHash() {
return errors.New("ErrCorruptedKey")
}
}
txn := types.Transaction{
SiafundInputs: []types.SiafundInput{
types.SiafundInput{
UnlockConditions: loadedKeys[0].UnlockConditions,
},
},
}
var i uint64
for i != totalKeys {
if i+keysRequired > totalKeys {
i = totalKeys - keysRequired
}
var j uint64
for j < keysRequired {
txn.TransactionSignatures = append(txn.TransactionSignatures, types.TransactionSignature{
PublicKeyIndex: i,
CoveredFields: types.CoveredFields{WholeTransaction: true},
})
sigHash := txn.SigHash(int(j))
sig, err := crypto.SignHash(sigHash, loadedKeys[i].SecretKey)
if err != nil {
return err
}
txn.TransactionSignatures[j].Signature = sig[:]
i++
j++
}
err := txn.StandaloneValid(0)
if err != nil {
return err
}
txn.TransactionSignatures = nil
}
return nil
}
// reviseObligation takes a file contract revision + transaction and applies it
// to an existing obligation.
func (h *Host) reviseObligation(revisionTransaction types.Transaction) {
// Sanity checks - there should be exactly one revision in the transaction,
// and that revision should correspond to a known obligation.
fcrlen := len(revisionTransaction.FileContractRevisions)
if fcrlen != 1 {
h.log.Critical("reviseObligation: revisionTransaction has the wrong number of revisions:", fcrlen)
return
}
obligation, exists := h.obligationsByID[revisionTransaction.FileContractRevisions[0].ParentID]
if !exists {
h.log.Critical("reviseObligation: revisionTransaction has no corresponding obligation")
return
}
// Expensive Sanity check - obligation being added should have a valid tranasction.
if build.DEBUG {
err := revisionTransaction.StandaloneValid(h.blockHeight)
if err != nil {
h.log.Critical("invalid transaction is being added in an obligation")
}
}
// Update the host's statistics.
h.spaceRemaining += int64(obligation.fileSize())
h.spaceRemaining -= int64(revisionTransaction.FileContractRevisions[0].NewFileSize)
h.anticipatedRevenue = h.anticipatedRevenue.Sub(obligation.value())
h.anticipatedRevenue = h.anticipatedRevenue.Add(revisionTransaction.FileContractRevisions[0].NewValidProofOutputs[1].Value)
// The host needs to verify that the revision transaction made it into the
// blockchain.
h.addActionItem(h.blockHeight+resubmissionTimeout, obligation)
// Add the revision to the obligation
obligation.RevisionTransaction = revisionTransaction
obligation.RevisionConfirmed = false
err := obligation.isSane()
if err != nil {
h.log.Critical("reviseObligation: obligation is not sane: " + err.Error())
}
err = h.save()
if err != nil {
h.log.Println("WARN: failed to save host:", err)
}
}
// VerifyFileContractRevisionTransactionSignatures checks that the signatures
// on a file contract revision are valid and cover the right fields.
func VerifyFileContractRevisionTransactionSignatures(fcr types.FileContractRevision, tsigs []types.TransactionSignature, height types.BlockHeight) error {
if len(tsigs) != 2 {
return ErrRevisionSigCount
}
for _, tsig := range tsigs {
// The transaction needs to be malleable so that miner fees can be
// added. If the whole transaction is covered, it is doomed to have no
// fees.
if tsig.CoveredFields.WholeTransaction {
return ErrRevisionCoveredFields
}
}
txn := types.Transaction{
FileContractRevisions: []types.FileContractRevision{fcr},
TransactionSignatures: tsigs,
}
// Check that the signatures verify. This will also check that the covered
// fields object is not over-aggressive, because if the object is pointing
// to elements that haven't been added to the transaction, verification
// will fail.
return txn.StandaloneValid(height)
}
func TestReviseContract(t *testing.T) {
if testing.Short() {
t.SkipNow()
}
t.Parallel()
ct, err := newContractorTester("TestReviseContract")
if err != nil {
t.Fatal(err)
}
// get an address
ourAddr, err := ct.wallet.NextAddress()
if err != nil {
t.Fatal(err)
}
// generate keys
sk, pk, err := crypto.GenerateKeyPair()
if err != nil {
t.Fatal(err)
}
renterPubKey := types.SiaPublicKey{
Algorithm: types.SignatureEd25519,
Key: pk[:],
}
uc := types.UnlockConditions{
PublicKeys: []types.SiaPublicKey{renterPubKey, renterPubKey},
SignaturesRequired: 1,
}
// create file contract
payout := types.NewCurrency64(1e16)
fc := types.FileContract{
FileSize: 0,
FileMerkleRoot: crypto.Hash{}, // no proof possible without data
WindowStart: 100,
WindowEnd: 1000,
Payout: payout,
UnlockHash: uc.UnlockHash(),
RevisionNumber: 0,
}
// outputs need account for tax
fc.ValidProofOutputs = []types.SiacoinOutput{
{Value: types.PostTax(ct.contractor.blockHeight, payout), UnlockHash: ourAddr.UnlockHash()},
{Value: types.ZeroCurrency, UnlockHash: types.UnlockHash{}}, // no collateral
}
fc.MissedProofOutputs = []types.SiacoinOutput{
// same as above
fc.ValidProofOutputs[0],
// goes to the void, not the hostdb
{Value: types.ZeroCurrency, UnlockHash: types.UnlockHash{}},
}
txnBuilder := ct.wallet.StartTransaction()
err = txnBuilder.FundSiacoins(fc.Payout)
if err != nil {
t.Fatal(err)
}
txnBuilder.AddFileContract(fc)
signedTxnSet, err := txnBuilder.Sign(true)
if err != nil {
t.Fatal(err)
}
// submit contract
err = ct.tpool.AcceptTransactionSet(signedTxnSet)
if err != nil {
t.Fatal(err)
}
// create revision
fcid := signedTxnSet[len(signedTxnSet)-1].FileContractID(0)
rev := types.FileContractRevision{
ParentID: fcid,
UnlockConditions: uc,
NewFileSize: 10,
NewWindowStart: 100,
NewWindowEnd: 1000,
NewRevisionNumber: 1,
NewValidProofOutputs: fc.ValidProofOutputs,
NewMissedProofOutputs: fc.MissedProofOutputs,
}
// create transaction containing the revision
signedTxn := types.Transaction{
FileContractRevisions: []types.FileContractRevision{rev},
TransactionSignatures: []types.TransactionSignature{{
ParentID: crypto.Hash(fcid),
CoveredFields: types.CoveredFields{FileContractRevisions: []uint64{0}},
PublicKeyIndex: 0, // hostdb key is always first -- see negotiateContract
}},
}
// sign the transaction
encodedSig, err := crypto.SignHash(signedTxn.SigHash(0), sk)
if err != nil {
t.Fatal(err)
}
signedTxn.TransactionSignatures[0].Signature = encodedSig[:]
err = signedTxn.StandaloneValid(ct.contractor.blockHeight)
if err != nil {
t.Fatal(err)
}
// submit revision
err = ct.tpool.AcceptTransactionSet([]types.Transaction{signedTxn})
if err != nil {
t.Fatal(err)
}
}
// revise revises fc to cover piece and uploads both the revision and the
// piece data to the host.
func (hu *hostUploader) revise(fc types.FileContract, piece []byte, height types.BlockHeight) error {
hu.conn.SetDeadline(time.Now().Add(5 * time.Minute)) // sufficient to transfer 4 MB over 100 kbps
defer hu.conn.SetDeadline(time.Time{}) // reset timeout after each revision
// calculate new merkle root
err := hu.tree.ReadSegments(bytes.NewReader(piece))
if err != nil {
return err
}
// create revision
rev := types.FileContractRevision{
ParentID: hu.contract.ID,
UnlockConditions: hu.unlockConditions,
NewRevisionNumber: fc.RevisionNumber + 1,
NewFileSize: fc.FileSize + uint64(len(piece)),
NewFileMerkleRoot: hu.tree.Root(),
NewWindowStart: fc.WindowStart,
NewWindowEnd: fc.WindowEnd,
NewValidProofOutputs: fc.ValidProofOutputs,
NewMissedProofOutputs: fc.MissedProofOutputs,
NewUnlockHash: fc.UnlockHash,
}
// transfer value of piece from renter to host
safeDuration := uint64(fc.WindowStart - height + 20) // buffer in case host is behind
piecePrice := types.NewCurrency64(uint64(len(piece))).Mul(types.NewCurrency64(safeDuration)).Mul(hu.settings.Price)
// prevent a negative currency panic
if piecePrice.Cmp(fc.ValidProofOutputs[0].Value) > 0 {
// probably not enough money, but the host might accept it anyway
piecePrice = fc.ValidProofOutputs[0].Value
}
rev.NewValidProofOutputs[0].Value = rev.NewValidProofOutputs[0].Value.Sub(piecePrice) // less returned to renter
rev.NewValidProofOutputs[1].Value = rev.NewValidProofOutputs[1].Value.Add(piecePrice) // more given to host
rev.NewMissedProofOutputs[0].Value = rev.NewMissedProofOutputs[0].Value.Sub(piecePrice) // less returned to renter
rev.NewMissedProofOutputs[1].Value = rev.NewMissedProofOutputs[1].Value.Add(piecePrice) // more given to void
// create transaction containing the revision
signedTxn := types.Transaction{
FileContractRevisions: []types.FileContractRevision{rev},
TransactionSignatures: []types.TransactionSignature{{
ParentID: crypto.Hash(hu.contract.ID),
CoveredFields: types.CoveredFields{FileContractRevisions: []uint64{0}},
PublicKeyIndex: 0, // renter key is always first -- see negotiateContract
}},
}
// sign the transaction
encodedSig, err := crypto.SignHash(signedTxn.SigHash(0), hu.secretKey)
if err != nil {
return err
}
signedTxn.TransactionSignatures[0].Signature = encodedSig[:]
// send the transaction
if err := encoding.WriteObject(hu.conn, signedTxn); err != nil {
return err
}
// host sends acceptance
var response string
if err := encoding.ReadObject(hu.conn, &response, 128); err != nil {
return err
}
if response != modules.AcceptResponse {
return errors.New("host rejected revision: " + response)
}
// transfer piece
if _, err := hu.conn.Write(piece); err != nil {
return err
}
// read txn signed by host
var signedHostTxn types.Transaction
if err := encoding.ReadObject(hu.conn, &signedHostTxn, types.BlockSizeLimit); err != nil {
return err
}
if signedHostTxn.ID() != signedTxn.ID() {
return errors.New("host sent bad signed transaction")
} else if err = signedHostTxn.StandaloneValid(height); err != nil {
return err
}
hu.lastTxn = signedHostTxn
return nil
}
// verifyKeys checks a set of keys on disk to see that they can spend funds
// sent to their address.
func verifyKeys(uc types.UnlockConditions, folder string, keyname string) error {
keysRequired := uc.SignaturesRequired
totalKeys := uint64(len(uc.PublicKeys))
// Load the keys from disk back into memory, then verify that the keys on
// disk are able to sign outputs in transactions.
loadedKeys := make([]KeyPair, totalKeys)
for i := 0; i < len(loadedKeys); i++ {
err := encoding.ReadFile(filepath.Join(folder, keyname+"_Key"+strconv.Itoa(i)+FileExtension), &loadedKeys[i])
if err != nil {
return err
}
if loadedKeys[i].Header != FileHeader {
return ErrUnknownHeader
}
if loadedKeys[i].Version != FileVersion {
return ErrUnknownVersion
}
}
// Check that the keys can be used to spend transactions.
for _, loadedKey := range loadedKeys {
if loadedKey.UnlockConditions.UnlockHash() != uc.UnlockHash() {
return ErrCorruptedKey
}
}
// Create a transaction for the keys to sign.
txn := types.Transaction{
SiafundInputs: []types.SiafundInput{
types.SiafundInput{
UnlockConditions: loadedKeys[0].UnlockConditions,
},
},
}
// Loop through and sign the transaction multiple times. All keys will be
// used at least once by the time the loop terminates.
var i uint64
for i != totalKeys {
// i tracks which key is next to be used. If i + RequiredKeys results
// in going out-of-bounds, reduce i so that the last key will be used
// for the final signature.
if i+keysRequired > totalKeys {
i = totalKeys - keysRequired
}
var j uint64
for j < keysRequired {
txn.TransactionSignatures = append(txn.TransactionSignatures, types.TransactionSignature{
PublicKeyIndex: i,
CoveredFields: types.CoveredFields{WholeTransaction: true},
})
sigHash := txn.SigHash(int(j))
sig, err := crypto.SignHash(sigHash, loadedKeys[i].SecretKey)
if err != nil {
return err
}
txn.TransactionSignatures[j].Signature = sig[:]
i++
j++
}
// Check that the signature is valid.
err := txn.StandaloneValid(0)
if err != nil {
return err
}
// Delete all of the signatures for the next iteration.
txn.TransactionSignatures = nil
}
return nil
}
