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store.go
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store.go
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// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package streams
import (
"bytes"
"context"
"crypto/rand"
"fmt"
"io"
"io/ioutil"
"strings"
"time"
"github.com/gogo/protobuf/proto"
"github.com/zeebo/errs"
"go.uber.org/zap"
monkit "gopkg.in/spacemonkeygo/monkit.v2"
"storj.io/storj/pkg/eestream"
"storj.io/storj/pkg/encryption"
"storj.io/storj/pkg/pb"
"storj.io/storj/pkg/ranger"
"storj.io/storj/pkg/storage/meta"
"storj.io/storj/pkg/storage/segments"
"storj.io/storj/pkg/storj"
"storj.io/storj/storage"
)
var mon = monkit.Package()
// Meta info about a stream
type Meta struct {
Modified time.Time
Expiration time.Time
Size int64
Data []byte
}
// convertMeta converts segment metadata to stream metadata
func convertMeta(lastSegmentMeta segments.Meta, stream pb.StreamInfo, streamMeta pb.StreamMeta) Meta {
return Meta{
Modified: lastSegmentMeta.Modified,
Expiration: lastSegmentMeta.Expiration,
Size: ((stream.NumberOfSegments - 1) * stream.SegmentsSize) + stream.LastSegmentSize,
Data: stream.Metadata,
}
}
// Store interface methods for streams to satisfy to be a store
type Store interface {
Meta(ctx context.Context, path storj.Path, pathCipher storj.Cipher) (Meta, error)
Get(ctx context.Context, path storj.Path, pathCipher storj.Cipher) (ranger.Ranger, Meta, error)
Put(ctx context.Context, path storj.Path, pathCipher storj.Cipher, data io.Reader, metadata []byte, expiration time.Time) (Meta, error)
Delete(ctx context.Context, path storj.Path, pathCipher storj.Cipher) error
List(ctx context.Context, prefix, startAfter, endBefore storj.Path, pathCipher storj.Cipher, recursive bool, limit int, metaFlags uint32) (items []ListItem, more bool, err error)
}
// streamStore is a store for streams
type streamStore struct {
segments segments.Store
segmentSize int64
rootKey *storj.Key
encBlockSize int
cipher storj.Cipher
}
// NewStreamStore stuff
func NewStreamStore(segments segments.Store, segmentSize int64, rootKey *storj.Key, encBlockSize int, cipher storj.Cipher) (Store, error) {
if segmentSize <= 0 {
return nil, errs.New("segment size must be larger than 0")
}
if rootKey == nil {
return nil, errs.New("encryption key must not be empty")
}
if encBlockSize <= 0 {
return nil, errs.New("encryption block size must be larger than 0")
}
return &streamStore{
segments: segments,
segmentSize: segmentSize,
rootKey: rootKey,
encBlockSize: encBlockSize,
cipher: cipher,
}, nil
}
// Put breaks up data as it comes in into s.segmentSize length pieces, then
// store the first piece at s0/<path>, second piece at s1/<path>, and the
// *last* piece at l/<path>. Store the given metadata, along with the number
// of segments, in a new protobuf, in the metadata of l/<path>.
func (s *streamStore) Put(ctx context.Context, path storj.Path, pathCipher storj.Cipher, data io.Reader, metadata []byte, expiration time.Time) (m Meta, err error) {
defer mon.Task()(&ctx)(&err)
// previously file uploaded?
err = s.Delete(ctx, path, pathCipher)
if err != nil && !storage.ErrKeyNotFound.Has(err) {
//something wrong happened checking for an existing
//file with the same name
return Meta{}, err
}
m, lastSegment, err := s.upload(ctx, path, pathCipher, data, metadata, expiration)
if err != nil {
s.cancelHandler(context.Background(), lastSegment, path, pathCipher)
}
return m, err
}
func (s *streamStore) upload(ctx context.Context, path storj.Path, pathCipher storj.Cipher, data io.Reader, metadata []byte, expiration time.Time) (m Meta, lastSegment int64, err error) {
defer mon.Task()(&ctx)(&err)
var currentSegment int64
var streamSize int64
var putMeta segments.Meta
defer func() {
select {
case <-ctx.Done():
s.cancelHandler(context.Background(), currentSegment, path, pathCipher)
default:
}
}()
derivedKey, err := encryption.DeriveContentKey(path, s.rootKey)
if err != nil {
return Meta{}, currentSegment, err
}
eofReader := NewEOFReader(data)
for !eofReader.isEOF() && !eofReader.hasError() {
// generate random key for encrypting the segment's content
var contentKey storj.Key
_, err = rand.Read(contentKey[:])
if err != nil {
return Meta{}, currentSegment, err
}
// Initialize the content nonce with the segment's index incremented by 1.
// The increment by 1 is to avoid nonce reuse with the metadata encryption,
// which is encrypted with the zero nonce.
var contentNonce storj.Nonce
_, err := encryption.Increment(&contentNonce, currentSegment+1)
if err != nil {
return Meta{}, currentSegment, err
}
encrypter, err := encryption.NewEncrypter(s.cipher, &contentKey, &contentNonce, s.encBlockSize)
if err != nil {
return Meta{}, currentSegment, err
}
// generate random nonce for encrypting the content key
var keyNonce storj.Nonce
_, err = rand.Read(keyNonce[:])
if err != nil {
return Meta{}, currentSegment, err
}
encryptedKey, err := encryption.EncryptKey(&contentKey, s.cipher, derivedKey, &keyNonce)
if err != nil {
return Meta{}, currentSegment, err
}
sizeReader := NewSizeReader(eofReader)
segmentReader := io.LimitReader(sizeReader, s.segmentSize)
peekReader := segments.NewPeekThresholdReader(segmentReader)
largeData, err := peekReader.IsLargerThan(encrypter.InBlockSize())
if err != nil {
return Meta{}, currentSegment, err
}
var transformedReader io.Reader
if largeData {
paddedReader := eestream.PadReader(ioutil.NopCloser(peekReader), encrypter.InBlockSize())
transformedReader = encryption.TransformReader(paddedReader, encrypter, 0)
} else {
data, err := ioutil.ReadAll(peekReader)
if err != nil {
return Meta{}, currentSegment, err
}
cipherData, err := encryption.Encrypt(data, s.cipher, &contentKey, &contentNonce)
if err != nil {
return Meta{}, currentSegment, err
}
transformedReader = bytes.NewReader(cipherData)
}
putMeta, err = s.segments.Put(ctx, transformedReader, expiration, func() (storj.Path, []byte, error) {
encPath, err := EncryptAfterBucket(path, pathCipher, s.rootKey)
if err != nil {
return "", nil, err
}
if !eofReader.isEOF() {
segmentPath := getSegmentPath(encPath, currentSegment)
if s.cipher == storj.Unencrypted {
return segmentPath, nil, nil
}
segmentMeta, err := proto.Marshal(&pb.SegmentMeta{
EncryptedKey: encryptedKey,
KeyNonce: keyNonce[:],
})
if err != nil {
return "", nil, err
}
return segmentPath, segmentMeta, nil
}
lastSegmentPath := storj.JoinPaths("l", encPath)
streamInfo, err := proto.Marshal(&pb.StreamInfo{
NumberOfSegments: currentSegment + 1,
SegmentsSize: s.segmentSize,
LastSegmentSize: sizeReader.Size(),
Metadata: metadata,
})
if err != nil {
return "", nil, err
}
// encrypt metadata with the content encryption key and zero nonce
encryptedStreamInfo, err := encryption.Encrypt(streamInfo, s.cipher, &contentKey, &storj.Nonce{})
if err != nil {
return "", nil, err
}
streamMeta := pb.StreamMeta{
EncryptedStreamInfo: encryptedStreamInfo,
EncryptionType: int32(s.cipher),
EncryptionBlockSize: int32(s.encBlockSize),
}
if s.cipher != storj.Unencrypted {
streamMeta.LastSegmentMeta = &pb.SegmentMeta{
EncryptedKey: encryptedKey,
KeyNonce: keyNonce[:],
}
}
lastSegmentMeta, err := proto.Marshal(&streamMeta)
if err != nil {
return "", nil, err
}
return lastSegmentPath, lastSegmentMeta, nil
})
if err != nil {
return Meta{}, currentSegment, err
}
currentSegment++
streamSize += sizeReader.Size()
}
if eofReader.hasError() {
return Meta{}, currentSegment, eofReader.err
}
resultMeta := Meta{
Modified: putMeta.Modified,
Expiration: expiration,
Size: streamSize,
Data: metadata,
}
return resultMeta, currentSegment, nil
}
// getSegmentPath returns the unique path for a particular segment
func getSegmentPath(path storj.Path, segNum int64) storj.Path {
return storj.JoinPaths(fmt.Sprintf("s%d", segNum), path)
}
// Get returns a ranger that knows what the overall size is (from l/<path>)
// and then returns the appropriate data from segments s0/<path>, s1/<path>,
// ..., l/<path>.
func (s *streamStore) Get(ctx context.Context, path storj.Path, pathCipher storj.Cipher) (rr ranger.Ranger, meta Meta, err error) {
defer mon.Task()(&ctx)(&err)
encPath, err := EncryptAfterBucket(path, pathCipher, s.rootKey)
if err != nil {
return nil, Meta{}, err
}
lastSegmentRanger, lastSegmentMeta, err := s.segments.Get(ctx, storj.JoinPaths("l", encPath))
if err != nil {
return nil, Meta{}, err
}
streamInfo, streamMeta, err := DecryptStreamInfo(ctx, lastSegmentMeta.Data, path, s.rootKey)
if err != nil {
return nil, Meta{}, err
}
stream := pb.StreamInfo{}
err = proto.Unmarshal(streamInfo, &stream)
if err != nil {
return nil, Meta{}, err
}
derivedKey, err := encryption.DeriveContentKey(path, s.rootKey)
if err != nil {
return nil, Meta{}, err
}
var rangers []ranger.Ranger
for i := int64(0); i < stream.NumberOfSegments-1; i++ {
currentPath := getSegmentPath(encPath, i)
size := stream.SegmentsSize
var contentNonce storj.Nonce
_, err := encryption.Increment(&contentNonce, i+1)
if err != nil {
return nil, Meta{}, err
}
rr := &lazySegmentRanger{
segments: s.segments,
path: currentPath,
size: size,
derivedKey: derivedKey,
startingNonce: &contentNonce,
encBlockSize: int(streamMeta.EncryptionBlockSize),
cipher: storj.Cipher(streamMeta.EncryptionType),
}
rangers = append(rangers, rr)
}
var contentNonce storj.Nonce
_, err = encryption.Increment(&contentNonce, stream.NumberOfSegments)
if err != nil {
return nil, Meta{}, err
}
encryptedKey, keyNonce := getEncryptedKeyAndNonce(streamMeta.LastSegmentMeta)
decryptedLastSegmentRanger, err := decryptRanger(
ctx,
lastSegmentRanger,
stream.LastSegmentSize,
storj.Cipher(streamMeta.EncryptionType),
derivedKey,
encryptedKey,
keyNonce,
&contentNonce,
int(streamMeta.EncryptionBlockSize),
)
if err != nil {
return nil, Meta{}, err
}
rangers = append(rangers, decryptedLastSegmentRanger)
catRangers := ranger.Concat(rangers...)
meta = convertMeta(lastSegmentMeta, stream, streamMeta)
return catRangers, meta, nil
}
// Meta implements Store.Meta
func (s *streamStore) Meta(ctx context.Context, path storj.Path, pathCipher storj.Cipher) (meta Meta, err error) {
defer mon.Task()(&ctx)(&err)
encPath, err := EncryptAfterBucket(path, pathCipher, s.rootKey)
if err != nil {
return Meta{}, err
}
lastSegmentMeta, err := s.segments.Meta(ctx, storj.JoinPaths("l", encPath))
if err != nil {
return Meta{}, err
}
streamInfo, streamMeta, err := DecryptStreamInfo(ctx, lastSegmentMeta.Data, path, s.rootKey)
if err != nil {
return Meta{}, err
}
var stream pb.StreamInfo
if err := proto.Unmarshal(streamInfo, &stream); err != nil {
return Meta{}, err
}
return convertMeta(lastSegmentMeta, stream, streamMeta), nil
}
// Delete all the segments, with the last one last
func (s *streamStore) Delete(ctx context.Context, path storj.Path, pathCipher storj.Cipher) (err error) {
defer mon.Task()(&ctx)(&err)
encPath, err := EncryptAfterBucket(path, pathCipher, s.rootKey)
if err != nil {
return err
}
lastSegmentMeta, err := s.segments.Meta(ctx, storj.JoinPaths("l", encPath))
if err != nil {
return err
}
streamInfo, _, err := DecryptStreamInfo(ctx, lastSegmentMeta.Data, path, s.rootKey)
if err != nil {
return err
}
var stream pb.StreamInfo
if err := proto.Unmarshal(streamInfo, &stream); err != nil {
return err
}
for i := 0; i < int(stream.NumberOfSegments-1); i++ {
encPath, err = EncryptAfterBucket(path, pathCipher, s.rootKey)
if err != nil {
return err
}
currentPath := getSegmentPath(encPath, int64(i))
err := s.segments.Delete(ctx, currentPath)
if err != nil {
return err
}
}
return s.segments.Delete(ctx, storj.JoinPaths("l", encPath))
}
// ListItem is a single item in a listing
type ListItem struct {
Path storj.Path
Meta Meta
IsPrefix bool
}
// List all the paths inside l/, stripping off the l/ prefix
func (s *streamStore) List(ctx context.Context, prefix, startAfter, endBefore storj.Path, pathCipher storj.Cipher, recursive bool, limit int, metaFlags uint32) (items []ListItem, more bool, err error) {
defer mon.Task()(&ctx)(&err)
if metaFlags&meta.Size != 0 {
// Calculating the stream's size require also the user-defined metadata,
// where stream store keeps info about the number of segments and their size.
metaFlags |= meta.UserDefined
}
prefix = strings.TrimSuffix(prefix, "/")
encPrefix, err := EncryptAfterBucket(prefix, pathCipher, s.rootKey)
if err != nil {
return nil, false, err
}
prefixKey, err := encryption.DerivePathKey(prefix, s.rootKey, len(storj.SplitPath(prefix)))
if err != nil {
return nil, false, err
}
encStartAfter, err := s.encryptMarker(startAfter, pathCipher, prefixKey)
if err != nil {
return nil, false, err
}
encEndBefore, err := s.encryptMarker(endBefore, pathCipher, prefixKey)
if err != nil {
return nil, false, err
}
segments, more, err := s.segments.List(ctx, storj.JoinPaths("l", encPrefix), encStartAfter, encEndBefore, recursive, limit, metaFlags)
if err != nil {
return nil, false, err
}
items = make([]ListItem, len(segments))
for i, item := range segments {
path, err := s.decryptMarker(item.Path, pathCipher, prefixKey)
if err != nil {
return nil, false, err
}
streamInfo, streamMeta, err := DecryptStreamInfo(ctx, item.Meta.Data, storj.JoinPaths(prefix, path), s.rootKey)
if err != nil {
return nil, false, err
}
var stream pb.StreamInfo
if err := proto.Unmarshal(streamInfo, &stream); err != nil {
return nil, false, err
}
newMeta := convertMeta(item.Meta, stream, streamMeta)
items[i] = ListItem{Path: path, Meta: newMeta, IsPrefix: item.IsPrefix}
}
return items, more, nil
}
// encryptMarker is a helper method for encrypting startAfter and endBefore markers
func (s *streamStore) encryptMarker(marker storj.Path, pathCipher storj.Cipher, prefixKey *storj.Key) (storj.Path, error) {
if bytes.Equal(s.rootKey[:], prefixKey[:]) { // empty prefix
return EncryptAfterBucket(marker, pathCipher, s.rootKey)
}
return encryption.EncryptPath(marker, pathCipher, prefixKey)
}
// decryptMarker is a helper method for decrypting listed path markers
func (s *streamStore) decryptMarker(marker storj.Path, pathCipher storj.Cipher, prefixKey *storj.Key) (storj.Path, error) {
if bytes.Equal(s.rootKey[:], prefixKey[:]) { // empty prefix
return DecryptAfterBucket(marker, pathCipher, s.rootKey)
}
return encryption.DecryptPath(marker, pathCipher, prefixKey)
}
type lazySegmentRanger struct {
ranger ranger.Ranger
segments segments.Store
path storj.Path
size int64
derivedKey *storj.Key
startingNonce *storj.Nonce
encBlockSize int
cipher storj.Cipher
}
// Size implements Ranger.Size
func (lr *lazySegmentRanger) Size() int64 {
return lr.size
}
// Range implements Ranger.Range to be lazily connected
func (lr *lazySegmentRanger) Range(ctx context.Context, offset, length int64) (io.ReadCloser, error) {
if lr.ranger == nil {
rr, m, err := lr.segments.Get(ctx, lr.path)
if err != nil {
return nil, err
}
segmentMeta := pb.SegmentMeta{}
err = proto.Unmarshal(m.Data, &segmentMeta)
if err != nil {
return nil, err
}
encryptedKey, keyNonce := getEncryptedKeyAndNonce(&segmentMeta)
lr.ranger, err = decryptRanger(ctx, rr, lr.size, lr.cipher, lr.derivedKey, encryptedKey, keyNonce, lr.startingNonce, lr.encBlockSize)
if err != nil {
return nil, err
}
}
return lr.ranger.Range(ctx, offset, length)
}
// decryptRanger returns a decrypted ranger of the given rr ranger
func decryptRanger(ctx context.Context, rr ranger.Ranger, decryptedSize int64, cipher storj.Cipher, derivedKey *storj.Key, encryptedKey storj.EncryptedPrivateKey, encryptedKeyNonce, startingNonce *storj.Nonce, encBlockSize int) (decrypted ranger.Ranger, err error) {
contentKey, err := encryption.DecryptKey(encryptedKey, cipher, derivedKey, encryptedKeyNonce)
if err != nil {
return nil, err
}
decrypter, err := encryption.NewDecrypter(cipher, contentKey, startingNonce, encBlockSize)
if err != nil {
return nil, err
}
var rd ranger.Ranger
if rr.Size()%int64(decrypter.InBlockSize()) != 0 {
reader, err := rr.Range(ctx, 0, rr.Size())
if err != nil {
return nil, err
}
defer func() { err = errs.Combine(err, reader.Close()) }()
cipherData, err := ioutil.ReadAll(reader)
if err != nil {
return nil, err
}
data, err := encryption.Decrypt(cipherData, cipher, contentKey, startingNonce)
if err != nil {
return nil, err
}
return ranger.ByteRanger(data), nil
}
rd, err = encryption.Transform(rr, decrypter)
if err != nil {
return nil, err
}
return eestream.Unpad(rd, int(rd.Size()-decryptedSize))
}
// EncryptAfterBucket encrypts a path without encrypting its first element
func EncryptAfterBucket(path storj.Path, cipher storj.Cipher, key *storj.Key) (encrypted storj.Path, err error) {
comps := storj.SplitPath(path)
if len(comps) <= 1 {
return path, nil
}
encrypted, err = encryption.EncryptPath(path, cipher, key)
if err != nil {
return "", err
}
// replace the first path component with the unencrypted bucket name
return storj.JoinPaths(comps[0], storj.JoinPaths(storj.SplitPath(encrypted)[1:]...)), nil
}
// DecryptAfterBucket decrypts a path without modifying its first element
func DecryptAfterBucket(path storj.Path, cipher storj.Cipher, key *storj.Key) (decrypted storj.Path, err error) {
comps := storj.SplitPath(path)
if len(comps) <= 1 {
return path, nil
}
bucket := comps[0]
toDecrypt := storj.JoinPaths(comps[1:]...)
bucketKey, err := encryption.DerivePathKey(path, key, 1)
if err != nil {
return "", err
}
decPath, err := encryption.DecryptPath(toDecrypt, cipher, bucketKey)
if err != nil {
return "", err
}
return storj.JoinPaths(bucket, decPath), nil
}
// CancelHandler handles clean up of segments on receiving CTRL+C
func (s *streamStore) cancelHandler(ctx context.Context, totalSegments int64, path storj.Path, pathCipher storj.Cipher) {
for i := int64(0); i < totalSegments; i++ {
encPath, err := EncryptAfterBucket(path, pathCipher, s.rootKey)
if err != nil {
zap.S().Warnf("Failed deleting a segment due to encryption path %v %v", i, err)
}
currentPath := getSegmentPath(encPath, i)
err = s.segments.Delete(ctx, currentPath)
if err != nil {
zap.S().Warnf("Failed deleting a segment %v %v", currentPath, err)
}
}
}
func getEncryptedKeyAndNonce(m *pb.SegmentMeta) (storj.EncryptedPrivateKey, *storj.Nonce) {
if m == nil {
return nil, nil
}
var nonce storj.Nonce
copy(nonce[:], m.KeyNonce)
return m.EncryptedKey, &nonce
}
// DecryptStreamInfo decrypts stream info
func DecryptStreamInfo(ctx context.Context, streamMetaBytes []byte, path storj.Path, rootKey *storj.Key) (
streamInfo []byte, streamMeta pb.StreamMeta, err error) {
err = proto.Unmarshal(streamMetaBytes, &streamMeta)
if err != nil {
return nil, pb.StreamMeta{}, err
}
derivedKey, err := encryption.DeriveContentKey(path, rootKey)
if err != nil {
return nil, pb.StreamMeta{}, err
}
cipher := storj.Cipher(streamMeta.EncryptionType)
encryptedKey, keyNonce := getEncryptedKeyAndNonce(streamMeta.LastSegmentMeta)
contentKey, err := encryption.DecryptKey(encryptedKey, cipher, derivedKey, keyNonce)
if err != nil {
return nil, pb.StreamMeta{}, err
}
// decrypt metadata with the content encryption key and zero nonce
streamInfo, err = encryption.Decrypt(streamMeta.EncryptedStreamInfo, cipher, contentKey, &storj.Nonce{})
return streamInfo, streamMeta, err
}