// LoadString loads a hex representation (including checksum) of an unlock hash
// into an unlock hash object. An error is returned if the string is invalid or
// fails the checksum.
func (uh *UnlockHash) LoadString(strUH string) error {
// Check the length of strUH.
if len(strUH) != crypto.HashSize*2+UnlockHashChecksumSize*2 {
return ErrUnlockHashWrongLen
}
// Decode the unlock hash.
var byteUnlockHash []byte
var checksum []byte
_, err := fmt.Sscanf(strUH[:crypto.HashSize*2], "%x", &byteUnlockHash)
if err != nil {
return err
}
// Decode and verify the checksum.
_, err = fmt.Sscanf(strUH[crypto.HashSize*2:], "%x", &checksum)
if err != nil {
return err
}
expectedChecksum := crypto.HashBytes(byteUnlockHash)
if !bytes.Equal(expectedChecksum[:UnlockHashChecksumSize], checksum) {
return ErrInvalidUnlockHashChecksum
}
copy(uh[:], byteUnlockHash[:])
return nil
}
// LoadString loads a hex representation (including checksum) of an unlock hash
// into an unlock hash object. An error is returned if the string is invalid or
// fails the checksum.
func (uh *UnlockHash) LoadString(strUH string) error {
// Check the length of strUH.
if len(strUH) != crypto.HashSize*2+UnlockHashChecksumSize*2 && len(strUH) != crypto.HashSize*2 {
return ErrUnlockHashWrongLen
}
// Decode the unlock hash.
var byteUnlockHash []byte
var checksum []byte
_, err := fmt.Sscanf(strUH[:crypto.HashSize*2], "%x", &byteUnlockHash)
if err != nil {
return err
}
// Decode the checksum, if provided.
if len(strUH) == crypto.HashSize*2+UnlockHashChecksumSize*2 {
_, err = fmt.Sscanf(strUH[crypto.HashSize*2:], "%x", &checksum)
if err != nil {
return err
}
// Verify the checksum - leave uh as-is unless the checksum is valid.
expectedChecksum := crypto.HashBytes(byteUnlockHash)
if bytes.Compare(expectedChecksum[:UnlockHashChecksumSize], checksum) != 0 {
return ErrInvalidUnlockHashChecksum
}
}
copy(uh[:], byteUnlockHash[:])
return nil
}
// SigHash returns the hash of the fields in a transaction covered by a given
// signature. See CoveredFields for more details.
func (t Transaction) SigHash(i int) crypto.Hash {
cf := t.TransactionSignatures[i].CoveredFields
var signedData []byte
if cf.WholeTransaction {
signedData = encoding.MarshalAll(
t.SiacoinInputs,
t.SiacoinOutputs,
t.FileContracts,
t.FileContractRevisions,
t.StorageProofs,
t.SiafundInputs,
t.SiafundOutputs,
t.MinerFees,
t.ArbitraryData,
t.TransactionSignatures[i].ParentID,
t.TransactionSignatures[i].PublicKeyIndex,
t.TransactionSignatures[i].Timelock,
)
} else {
for _, input := range cf.SiacoinInputs {
signedData = append(signedData, encoding.Marshal(t.SiacoinInputs[input])...)
}
for _, output := range cf.SiacoinOutputs {
signedData = append(signedData, encoding.Marshal(t.SiacoinOutputs[output])...)
}
for _, contract := range cf.FileContracts {
signedData = append(signedData, encoding.Marshal(t.FileContracts[contract])...)
}
for _, revision := range cf.FileContractRevisions {
signedData = append(signedData, encoding.Marshal(t.FileContractRevisions[revision])...)
}
for _, storageProof := range cf.StorageProofs {
signedData = append(signedData, encoding.Marshal(t.StorageProofs[storageProof])...)
}
for _, siafundInput := range cf.SiafundInputs {
signedData = append(signedData, encoding.Marshal(t.SiafundInputs[siafundInput])...)
}
for _, siafundOutput := range cf.SiafundOutputs {
signedData = append(signedData, encoding.Marshal(t.SiafundOutputs[siafundOutput])...)
}
for _, minerFee := range cf.MinerFees {
signedData = append(signedData, encoding.Marshal(t.MinerFees[minerFee])...)
}
for _, arbData := range cf.ArbitraryData {
signedData = append(signedData, encoding.Marshal(t.ArbitraryData[arbData])...)
}
}
for _, sig := range cf.TransactionSignatures {
signedData = append(signedData, encoding.Marshal(t.TransactionSignatures[sig])...)
}
return crypto.HashBytes(signedData)
}
// SolveBlock takes a block, target, and number of iterations as input and
// tries to find a block that meets the target. This function can take a long
// time to complete, and should not be called with a lock.
func (m *Miner) SolveBlock(b types.Block, target types.Target) (types.Block, bool) {
// Assemble the header.
merkleRoot := b.MerkleRoot()
header := make([]byte, 80)
copy(header, b.ParentID[:])
binary.LittleEndian.PutUint64(header[40:48], uint64(b.Timestamp))
copy(header[48:], merkleRoot[:])
nonce := (*uint64)(unsafe.Pointer(&header[32]))
for i := 0; i < iterationsPerAttempt; i++ {
id := crypto.HashBytes(header)
if bytes.Compare(target[:], id[:]) >= 0 {
copy(b.Nonce[:], header[32:40])
return b, true
}
*nonce++
}
return b, false
}
// TestBlockHeader checks that BlockHeader returns the correct value, and that
// the hash is consistent with the old method for obtaining the hash.
func TestBlockHeader(t *testing.T) {
var b Block
b.ParentID[1] = 1
b.Nonce[2] = 2
b.Timestamp = 3
b.MinerPayouts = []SiacoinOutput{{Value: NewCurrency64(4)}}
b.Transactions = []Transaction{{ArbitraryData: [][]byte{[]byte{'5'}}}}
id1 := b.ID()
id2 := BlockID(crypto.HashBytes(encoding.Marshal(b.Header())))
id3 := BlockID(crypto.HashAll(
b.ParentID,
b.Nonce,
b.Timestamp,
b.MerkleRoot(),
))
if id1 != id2 || id2 != id3 || id3 != id1 {
t.Error("Methods for getting block id don't return the same results")
}
}
// CreateAnnouncement will take a host announcement and encode it, returning
// the exact []byte that should be added to the arbitrary data of a
// transaction.
func CreateAnnouncement(addr NetAddress, pk types.SiaPublicKey, sk crypto.SecretKey) (signedAnnouncement []byte, err error) {
if err := addr.IsValid(); err != nil {
return nil, err
}
// Create the HostAnnouncement and marshal it.
annBytes := encoding.Marshal(HostAnnouncement{
Specifier: PrefixHostAnnouncement,
NetAddress: addr,
PublicKey: pk,
})
// Create a signature for the announcement.
annHash := crypto.HashBytes(annBytes)
sig, err := crypto.SignHash(annHash, sk)
if err != nil {
return nil, err
}
// Return the signed announcement.
return append(annBytes, sig[:]...), nil
}