// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum 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 go-ethereum 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 go-ethereum library. If not, see .
package storage
import (
"bytes"
"context"
"crypto"
"crypto/rand"
"encoding/binary"
"fmt"
"hash"
"io"
"sync"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto/sha3"
"github.com/ethereum/go-ethereum/swarm/bmt"
)
const MaxPO = 16
const KeyLength = 32
type Hasher func() hash.Hash
type SwarmHasher func() SwarmHash
// Peer is the recorded as Source on the chunk
// should probably not be here? but network should wrap chunk object
type Peer interface{}
type Address []byte
func (a Address) Size() uint {
return uint(len(a))
}
func (a Address) isEqual(y Address) bool {
return bytes.Equal(a, y)
}
func (a Address) bits(i, j uint) uint {
ii := i >> 3
jj := i & 7
if ii >= a.Size() {
return 0
}
if jj+j <= 8 {
return uint((a[ii] >> jj) & ((1 << j) - 1))
}
res := uint(a[ii] >> jj)
jj = 8 - jj
j -= jj
for j != 0 {
ii++
if j < 8 {
res += uint(a[ii]&((1< len(one) {
b = len(one)
}
m := 8
for i := 0; i < b; i++ {
oxo := one[i] ^ other[i]
if i == b-1 {
m = MaxPO % 8
}
for j := 0; j < m; j++ {
if (oxo>>uint8(7-j))&0x01 != 0 {
return i*8 + j
}
}
}
return MaxPO
}
func IsZeroAddr(addr Address) bool {
return len(addr) == 0 || bytes.Equal(addr, ZeroAddr)
}
var ZeroAddr = Address(common.Hash{}.Bytes())
func MakeHashFunc(hash string) SwarmHasher {
switch hash {
case "SHA256":
return func() SwarmHash { return &HashWithLength{crypto.SHA256.New()} }
case "SHA3":
return func() SwarmHash { return &HashWithLength{sha3.NewKeccak256()} }
case "BMT":
return func() SwarmHash {
hasher := sha3.NewKeccak256
pool := bmt.NewTreePool(hasher, bmt.SegmentCount, bmt.PoolSize)
return bmt.New(pool)
}
}
return nil
}
func (a Address) Hex() string {
return fmt.Sprintf("%064x", []byte(a[:]))
}
func (a Address) Log() string {
if len(a[:]) < 8 {
return fmt.Sprintf("%x", []byte(a[:]))
}
return fmt.Sprintf("%016x", []byte(a[:8]))
}
func (a Address) String() string {
return fmt.Sprintf("%064x", []byte(a)[:])
}
func (a Address) MarshalJSON() (out []byte, err error) {
return []byte(`"` + a.String() + `"`), nil
}
func (a *Address) UnmarshalJSON(value []byte) error {
s := string(value)
*a = make([]byte, 32)
h := common.Hex2Bytes(s[1 : len(s)-1])
copy(*a, h)
return nil
}
type AddressCollection []Address
func NewAddressCollection(l int) AddressCollection {
return make(AddressCollection, l)
}
func (c AddressCollection) Len() int {
return len(c)
}
func (c AddressCollection) Less(i, j int) bool {
return bytes.Compare(c[i], c[j]) == -1
}
func (c AddressCollection) Swap(i, j int) {
c[i], c[j] = c[j], c[i]
}
// Chunk also serves as a request object passed to ChunkStores
// in case it is a retrieval request, Data is nil and Size is 0
// Note that Size is not the size of the data chunk, which is Data.Size()
// but the size of the subtree encoded in the chunk
// 0 if request, to be supplied by the dpa
type Chunk struct {
Addr Address // always
SData []byte // nil if request, to be supplied by dpa
Size int64 // size of the data covered by the subtree encoded in this chunk
//Source Peer // peer
C chan bool // to signal data delivery by the dpa
ReqC chan bool // to signal the request done
dbStoredC chan bool // never remove a chunk from memStore before it is written to dbStore
dbStored bool
dbStoredMu *sync.Mutex
errored error // flag which is set when the chunk request has errored or timeouted
erroredMu sync.Mutex
}
func (c *Chunk) SetErrored(err error) {
c.erroredMu.Lock()
defer c.erroredMu.Unlock()
c.errored = err
}
func (c *Chunk) GetErrored() error {
c.erroredMu.Lock()
defer c.erroredMu.Unlock()
return c.errored
}
func NewChunk(addr Address, reqC chan bool) *Chunk {
return &Chunk{
Addr: addr,
ReqC: reqC,
dbStoredC: make(chan bool),
dbStoredMu: &sync.Mutex{},
}
}
func (c *Chunk) markAsStored() {
c.dbStoredMu.Lock()
defer c.dbStoredMu.Unlock()
if !c.dbStored {
close(c.dbStoredC)
c.dbStored = true
}
}
func (c *Chunk) WaitToStore() error {
<-c.dbStoredC
return c.GetErrored()
}
func GenerateRandomChunk(dataSize int64) *Chunk {
return GenerateRandomChunks(dataSize, 1)[0]
}
func GenerateRandomChunks(dataSize int64, count int) (chunks []*Chunk) {
var i int
hasher := MakeHashFunc(DefaultHash)()
if dataSize > DefaultChunkSize {
dataSize = DefaultChunkSize
}
for i = 0; i < count; i++ {
chunks = append(chunks, NewChunk(nil, nil))
chunks[i].SData = make([]byte, dataSize+8)
rand.Read(chunks[i].SData)
binary.LittleEndian.PutUint64(chunks[i].SData[:8], uint64(dataSize))
hasher.ResetWithLength(chunks[i].SData[:8])
hasher.Write(chunks[i].SData[8:])
chunks[i].Addr = make([]byte, 32)
copy(chunks[i].Addr, hasher.Sum(nil))
}
return chunks
}
// Size, Seek, Read, ReadAt
type LazySectionReader interface {
Context() context.Context
Size(context.Context, chan bool) (int64, error)
io.Seeker
io.Reader
io.ReaderAt
}
type LazyTestSectionReader struct {
*io.SectionReader
}
func (r *LazyTestSectionReader) Size(context.Context, chan bool) (int64, error) {
return r.SectionReader.Size(), nil
}
func (r *LazyTestSectionReader) Context() context.Context {
return context.TODO()
}
type StoreParams struct {
Hash SwarmHasher `toml:"-"`
DbCapacity uint64
CacheCapacity uint
ChunkRequestsCacheCapacity uint
BaseKey []byte
}
func NewDefaultStoreParams() *StoreParams {
return NewStoreParams(defaultLDBCapacity, defaultCacheCapacity, defaultChunkRequestsCacheCapacity, nil, nil)
}
func NewStoreParams(ldbCap uint64, cacheCap uint, requestsCap uint, hash SwarmHasher, basekey []byte) *StoreParams {
if basekey == nil {
basekey = make([]byte, 32)
}
if hash == nil {
hash = MakeHashFunc(DefaultHash)
}
return &StoreParams{
Hash: hash,
DbCapacity: ldbCap,
CacheCapacity: cacheCap,
ChunkRequestsCacheCapacity: requestsCap,
BaseKey: basekey,
}
}
type ChunkData []byte
type Reference []byte
// Putter is responsible to store data and create a reference for it
type Putter interface {
Put(context.Context, ChunkData) (Reference, error)
// RefSize returns the length of the Reference created by this Putter
RefSize() int64
// Close is to indicate that no more chunk data will be Put on this Putter
Close()
// Wait returns if all data has been store and the Close() was called.
Wait(context.Context) error
}
// Getter is an interface to retrieve a chunk's data by its reference
type Getter interface {
Get(context.Context, Reference) (ChunkData, error)
}
// NOTE: this returns invalid data if chunk is encrypted
func (c ChunkData) Size() int64 {
return int64(binary.LittleEndian.Uint64(c[:8]))
}
func (c ChunkData) Data() []byte {
return c[8:]
}
type ChunkValidator interface {
Validate(addr Address, data []byte) bool
}
// Provides method for validation of content address in chunks
// Holds the corresponding hasher to create the address
type ContentAddressValidator struct {
Hasher SwarmHasher
}
// Constructor
func NewContentAddressValidator(hasher SwarmHasher) *ContentAddressValidator {
return &ContentAddressValidator{
Hasher: hasher,
}
}
// Validate that the given key is a valid content address for the given data
func (v *ContentAddressValidator) Validate(addr Address, data []byte) bool {
hasher := v.Hasher()
hasher.ResetWithLength(data[:8])
hasher.Write(data[8:])
hash := hasher.Sum(nil)
return bytes.Equal(hash, addr[:])
}