path: root/core/db/level-db.go

// Copyright 2018 The dexon-consensus Authors
// This file is part of the dexon-consensus library.
//
// The dexon-consensus library is free software: you can redistribute it
// and/or modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation, either version 3 of the License,
// or (at your option) any later version.
//
// The dexon-consensus library is distributed in the hope that it will be
// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
// General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the dexon-consensus library. If not, see
// <http://www.gnu.org/licenses/>.

package db

import (
    "encoding/binary"
    "io"

    "github.com/syndtr/goleveldb/leveldb"

    "github.com/dexon-foundation/dexon-consensus/common"
    "github.com/dexon-foundation/dexon-consensus/core/crypto/dkg"
    "github.com/dexon-foundation/dexon-consensus/core/types"
    "github.com/dexon-foundation/dexon/rlp"
)

var (
    blockKeyPrefix            = []byte("b-")
    compactionChainTipInfoKey = []byte("cc-tip")
    dkgPrivateKeyKeyPrefix    = []byte("dkg-prvs")
    dkgProtocolInfoKeyPrefix  = []byte("dkg-protocol-info")
)

type compactionChainTipInfo struct {
    Height uint64      `json:"height"`
    Hash   common.Hash `json:"hash"`
}

// DKGProtocolInfo DKG protocol info.
type DKGProtocolInfo struct {
    ID                        types.NodeID
    Round                     uint64
    Threshold                 uint64
    IDMap                     NodeIDToDKGID
    MpkMap                    NodeIDToPubShares
    MasterPrivateShare        dkg.PrivateKeyShares
    IsMasterPrivateShareEmpty bool
    PrvShares                 dkg.PrivateKeyShares
    IsPrvSharesEmpty          bool
    PrvSharesReceived         NodeID
    NodeComplained            NodeID
    AntiComplaintReceived     NodeIDToNodeIDs
    Step                      uint64
    Reset                     uint64
}

type dkgPrivateKey struct {
    PK    dkg.PrivateKey
    Reset uint64
}

// Equal compare with target DKGProtocolInfo.
func (info *DKGProtocolInfo) Equal(target *DKGProtocolInfo) bool {
    if !info.ID.Equal(target.ID) ||
        info.Round != target.Round ||
        info.Threshold != target.Threshold ||
        info.IsMasterPrivateShareEmpty != target.IsMasterPrivateShareEmpty ||
        info.IsPrvSharesEmpty != target.IsPrvSharesEmpty ||
        info.Step != target.Step ||
        info.Reset != target.Reset ||
        !info.MasterPrivateShare.Equal(&target.MasterPrivateShare) ||
        !info.PrvShares.Equal(&target.PrvShares) {
        return false
    }

    if len(info.IDMap) != len(target.IDMap) {
        return false
    }
    for k, v := range info.IDMap {
        tV, exist := target.IDMap[k]
        if !exist {
            return false
        }

        if !v.IsEqual(&tV) {
            return false
        }
    }

    if len(info.MpkMap) != len(target.MpkMap) {
        return false
    }
    for k, v := range info.MpkMap {
        tV, exist := target.MpkMap[k]
        if !exist {
            return false
        }

        if !v.Equal(tV) {
            return false
        }
    }

    if len(info.PrvSharesReceived) != len(target.PrvSharesReceived) {
        return false
    }
    for k := range info.PrvSharesReceived {
        _, exist := target.PrvSharesReceived[k]
        if !exist {
            return false
        }
    }

    if len(info.NodeComplained) != len(target.NodeComplained) {
        return false
    }
    for k := range info.NodeComplained {
        _, exist := target.NodeComplained[k]
        if !exist {
            return false
        }
    }

    if len(info.AntiComplaintReceived) != len(target.AntiComplaintReceived) {
        return false
    }
    for k, v := range info.AntiComplaintReceived {
        tV, exist := target.AntiComplaintReceived[k]
        if !exist {
            return false
        }

        if len(v) != len(tV) {
            return false
        }
        for kk := range v {
            _, exist := tV[kk]
            if !exist {
                return false
            }
        }
    }

    return true
}

// NodeIDToNodeIDs the map with NodeID to NodeIDs.
type NodeIDToNodeIDs map[types.NodeID]map[types.NodeID]struct{}

// EncodeRLP implements rlp.Encoder
func (m NodeIDToNodeIDs) EncodeRLP(w io.Writer) error {
    var allBytes [][][]byte
    for k, v := range m {
        kBytes, err := k.MarshalText()
        if err != nil {
            return err
        }
        allBytes = append(allBytes, [][]byte{kBytes})

        var vBytes [][]byte
        for subK := range v {
            bytes, err := subK.MarshalText()
            if err != nil {
                return err
            }
            vBytes = append(vBytes, bytes)
        }
        allBytes = append(allBytes, vBytes)
    }

    return rlp.Encode(w, allBytes)
}

// DecodeRLP implements rlp.Encoder
func (m *NodeIDToNodeIDs) DecodeRLP(s *rlp.Stream) error {
    *m = make(NodeIDToNodeIDs)
    var dec [][][]byte
    if err := s.Decode(&dec); err != nil {
        return err
    }

    for i := 0; i < len(dec); i += 2 {
        key := types.NodeID{}
        err := key.UnmarshalText(dec[i][0])
        if err != nil {
            return err
        }

        valueMap := map[types.NodeID]struct{}{}
        for _, v := range dec[i+1] {
            value := types.NodeID{}
            err := value.UnmarshalText(v)
            if err != nil {
                return err
            }

            valueMap[value] = struct{}{}
        }

        (*m)[key] = valueMap
    }

    return nil
}

// NodeID the map with NodeID.
type NodeID map[types.NodeID]struct{}

// EncodeRLP implements rlp.Encoder
func (m NodeID) EncodeRLP(w io.Writer) error {
    var allBytes [][]byte
    for k := range m {
        kBytes, err := k.MarshalText()
        if err != nil {
            return err
        }
        allBytes = append(allBytes, kBytes)
    }

    return rlp.Encode(w, allBytes)
}

// DecodeRLP implements rlp.Encoder
func (m *NodeID) DecodeRLP(s *rlp.Stream) error {
    *m = make(NodeID)
    var dec [][]byte
    if err := s.Decode(&dec); err != nil {
        return err
    }

    for i := 0; i < len(dec); i++ {
        key := types.NodeID{}
        err := key.UnmarshalText(dec[i])
        if err != nil {
            return err
        }

        (*m)[key] = struct{}{}
    }

    return nil
}

// NodeIDToPubShares the map with NodeID to PublicKeyShares.
type NodeIDToPubShares map[types.NodeID]*dkg.PublicKeyShares

// EncodeRLP implements rlp.Encoder
func (m NodeIDToPubShares) EncodeRLP(w io.Writer) error {
    var allBytes [][]byte
    for k, v := range m {
        kBytes, err := k.MarshalText()
        if err != nil {
            return err
        }
        allBytes = append(allBytes, kBytes)

        bytes, err := rlp.EncodeToBytes(v)
        if err != nil {
            return err
        }
        allBytes = append(allBytes, bytes)
    }

    return rlp.Encode(w, allBytes)
}

// DecodeRLP implements rlp.Encoder
func (m *NodeIDToPubShares) DecodeRLP(s *rlp.Stream) error {
    *m = make(NodeIDToPubShares)
    var dec [][]byte
    if err := s.Decode(&dec); err != nil {
        return err
    }

    for i := 0; i < len(dec); i += 2 {
        key := types.NodeID{}
        err := key.UnmarshalText(dec[i])
        if err != nil {
            return err
        }

        value := dkg.PublicKeyShares{}
        err = rlp.DecodeBytes(dec[i+1], &value)
        if err != nil {
            return err
        }

        (*m)[key] = &value
    }

    return nil
}

// NodeIDToDKGID the map with NodeID to DKGID.
type NodeIDToDKGID map[types.NodeID]dkg.ID

// EncodeRLP implements rlp.Encoder
func (m NodeIDToDKGID) EncodeRLP(w io.Writer) error {
    var allBytes [][]byte
    for k, v := range m {
        kBytes, err := k.MarshalText()
        if err != nil {
            return err
        }
        allBytes = append(allBytes, kBytes)
        allBytes = append(allBytes, v.GetLittleEndian())
    }

    return rlp.Encode(w, allBytes)
}

// DecodeRLP implements rlp.Encoder
func (m *NodeIDToDKGID) DecodeRLP(s *rlp.Stream) error {
    *m = make(NodeIDToDKGID)
    var dec [][]byte
    if err := s.Decode(&dec); err != nil {
        return err
    }

    for i := 0; i < len(dec); i += 2 {
        key := types.NodeID{}
        err := key.UnmarshalText(dec[i])
        if err != nil {
            return err
        }

        value := dkg.ID{}
        err = value.SetLittleEndian(dec[i+1])
        if err != nil {
            return err
        }

        (*m)[key] = value
    }

    return nil
}

// LevelDBBackedDB is a leveldb backed DB implementation.
type LevelDBBackedDB struct {
    db *leveldb.DB
}

// NewLevelDBBackedDB initialize a leveldb-backed database.
func NewLevelDBBackedDB(
    path string) (lvl *LevelDBBackedDB, err error) {

    dbInst, err := leveldb.OpenFile(path, nil)
    if err != nil {
        return
    }
    lvl = &LevelDBBackedDB{db: dbInst}
    return
}

// Close implement Closer interface, which would release allocated resource.
func (lvl *LevelDBBackedDB) Close() error {
    return lvl.db.Close()
}

// HasBlock implements the Reader.Has method.
func (lvl *LevelDBBackedDB) HasBlock(hash common.Hash) bool {
    exists, err := lvl.internalHasBlock(lvl.getBlockKey(hash))
    if err != nil {
        panic(err)
    }
    return exists
}

func (lvl *LevelDBBackedDB) internalHasBlock(key []byte) (bool, error) {
    return lvl.db.Has(key, nil)
}

// GetBlock implements the Reader.GetBlock method.
func (lvl *LevelDBBackedDB) GetBlock(
    hash common.Hash) (block types.Block, err error) {
    queried, err := lvl.db.Get(lvl.getBlockKey(hash), nil)
    if err != nil {
        if err == leveldb.ErrNotFound {
            err = ErrBlockDoesNotExist
        }
        return
    }
    err = rlp.DecodeBytes(queried, &block)
    return
}

// UpdateBlock implements the Writer.UpdateBlock method.
func (lvl *LevelDBBackedDB) UpdateBlock(block types.Block) (err error) {
    // NOTE: we didn't handle changes of block hash (and it
    //       should not happen).
    marshaled, err := rlp.EncodeToBytes(&block)
    if err != nil {
        return
    }
    blockKey := lvl.getBlockKey(block.Hash)
    exists, err := lvl.internalHasBlock(blockKey)
    if err != nil {
        return
    }
    if !exists {
        err = ErrBlockDoesNotExist
        return
    }
    err = lvl.db.Put(blockKey, marshaled, nil)
    return
}

// PutBlock implements the Writer.PutBlock method.
func (lvl *LevelDBBackedDB) PutBlock(block types.Block) (err error) {
    marshaled, err := rlp.EncodeToBytes(&block)
    if err != nil {
        return
    }
    blockKey := lvl.getBlockKey(block.Hash)
    exists, err := lvl.internalHasBlock(blockKey)
    if err != nil {
        return
    }
    if exists {
        err = ErrBlockExists
        return
    }
    err = lvl.db.Put(blockKey, marshaled, nil)
    return
}

// GetAllBlocks implements Reader.GetAllBlocks method, which allows callers
// to retrieve all blocks in DB.
func (lvl *LevelDBBackedDB) GetAllBlocks() (BlockIterator, error) {
    return nil, ErrNotImplemented
}

// PutCompactionChainTipInfo saves tip of compaction chain into the database.
func (lvl *LevelDBBackedDB) PutCompactionChainTipInfo(
    blockHash common.Hash, height uint64) error {
    marshaled, err := rlp.EncodeToBytes(&compactionChainTipInfo{
        Hash:   blockHash,
        Height: height,
    })
    if err != nil {
        return err
    }
    // Check current cached tip info to make sure the one to be updated is
    // valid.
    info, err := lvl.internalGetCompactionChainTipInfo()
    if err != nil {
        return err
    }
    if info.Height+1 != height {
        return ErrInvalidCompactionChainTipHeight
    }
    return lvl.db.Put(compactionChainTipInfoKey, marshaled, nil)
}

func (lvl *LevelDBBackedDB) internalGetCompactionChainTipInfo() (
    info compactionChainTipInfo, err error) {
    queried, err := lvl.db.Get(compactionChainTipInfoKey, nil)
    if err != nil {
        if err == leveldb.ErrNotFound {
            err = nil
        }
        return
    }
    err = rlp.DecodeBytes(queried, &info)
    return
}

// GetCompactionChainTipInfo get the tip info of compaction chain into the
// database.
func (lvl *LevelDBBackedDB) GetCompactionChainTipInfo() (
    hash common.Hash, height uint64) {
    info, err := lvl.internalGetCompactionChainTipInfo()
    if err != nil {
        panic(err)
    }
    hash, height = info.Hash, info.Height
    return
}

// GetDKGPrivateKey get DKG private key of one round.
func (lvl *LevelDBBackedDB) GetDKGPrivateKey(round, reset uint64) (
    prv dkg.PrivateKey, err error) {
    queried, err := lvl.db.Get(lvl.getDKGPrivateKeyKey(round), nil)
    if err != nil {
        if err == leveldb.ErrNotFound {
            err = ErrDKGPrivateKeyDoesNotExist
        }
        return
    }
    pk := dkgPrivateKey{}
    err = rlp.DecodeBytes(queried, &pk)
    if pk.Reset != reset {
        err = ErrDKGPrivateKeyDoesNotExist
        return
    }
    prv = pk.PK
    return
}

// PutDKGPrivateKey save DKG private key of one round.
func (lvl *LevelDBBackedDB) PutDKGPrivateKey(
    round, reset uint64, prv dkg.PrivateKey) error {
    // Check existence.
    _, err := lvl.GetDKGPrivateKey(round, reset)
    if err == nil {
        return ErrDKGPrivateKeyExists
    }
    if err != ErrDKGPrivateKeyDoesNotExist {
        return err
    }
    pk := &dkgPrivateKey{
        PK:    prv,
        Reset: reset,
    }
    marshaled, err := rlp.EncodeToBytes(&pk)
    if err != nil {
        return err
    }
    return lvl.db.Put(
        lvl.getDKGPrivateKeyKey(round), marshaled, nil)
}

// GetDKGProtocol get DKG protocol.
func (lvl *LevelDBBackedDB) GetDKGProtocol() (
    info DKGProtocolInfo, err error) {
    queried, err := lvl.db.Get(lvl.getDKGProtocolInfoKey(), nil)
    if err != nil {
        if err == leveldb.ErrNotFound {
            err = ErrDKGProtocolDoesNotExist
        }
        return
    }

    err = rlp.DecodeBytes(queried, &info)
    return
}

// PutOrUpdateDKGProtocol save DKG protocol.
func (lvl *LevelDBBackedDB) PutOrUpdateDKGProtocol(info DKGProtocolInfo) error {
    marshaled, err := rlp.EncodeToBytes(&info)
    if err != nil {
        return err
    }
    return lvl.db.Put(lvl.getDKGProtocolInfoKey(), marshaled, nil)
}

func (lvl *LevelDBBackedDB) getBlockKey(hash common.Hash) (ret []byte) {
    ret = make([]byte, len(blockKeyPrefix)+len(hash[:]))
    copy(ret, blockKeyPrefix)
    copy(ret[len(blockKeyPrefix):], hash[:])
    return
}

func (lvl *LevelDBBackedDB) getDKGPrivateKeyKey(
    round uint64) (ret []byte) {
    ret = make([]byte, len(dkgPrivateKeyKeyPrefix)+8)
    copy(ret, dkgPrivateKeyKeyPrefix)
    binary.LittleEndian.PutUint64(
        ret[len(dkgPrivateKeyKeyPrefix):], round)
    return
}

func (lvl *LevelDBBackedDB) getDKGProtocolInfoKey() (ret []byte) {
    ret = make([]byte, len(dkgProtocolInfoKeyPrefix)+8)
    copy(ret, dkgProtocolInfoKeyPrefix)
    return
}