func TestEncryptWriter(t *testing.T) {
k := crypto.NewRandomKey()
tests := []int{5, 23, 2<<18 + 23, 1 << 20}
if testLargeCrypto {
tests = append(tests, 7<<20+123)
}
for _, size := range tests {
data := make([]byte, size)
_, err := io.ReadFull(RandomReader(42, size), data)
OK(t, err)
buf := bytes.NewBuffer(nil)
wr := crypto.EncryptTo(k, buf)
_, err = io.Copy(wr, bytes.NewReader(data))
OK(t, err)
OK(t, wr.Close())
ciphertext := buf.Bytes()
l := len(data) + crypto.Extension
Assert(t, len(ciphertext) == l,
"wrong ciphertext length: expected %d, got %d",
l, len(ciphertext))
// decrypt with default function
plaintext, err := crypto.Decrypt(k, []byte{}, ciphertext)
OK(t, err)
Assert(t, bytes.Equal(data, plaintext),
"wrong plaintext after decryption: expected %02x, got %02x",
data, plaintext)
}
}
// SaveJSONUnpacked serialises item as JSON and encrypts and saves it in the
// backend as type t, without a pack. It returns the storage hash.
func (s *Repository) SaveJSONUnpacked(t backend.Type, item interface{}) (backend.ID, error) {
// create file
blob, err := s.be.Create()
if err != nil {
return nil, err
}
debug.Log("Repo.SaveJSONUnpacked", "create new file %p", blob)
// hash
hw := backend.NewHashingWriter(blob, sha256.New())
// encrypt blob
ewr := crypto.EncryptTo(s.key, hw)
enc := json.NewEncoder(ewr)
err = enc.Encode(item)
if err != nil {
return nil, fmt.Errorf("json.Encode: %v", err)
}
err = ewr.Close()
if err != nil {
return nil, err
}
// finalize blob in the backend
sid := backend.ID(hw.Sum(nil))
err = blob.Finalize(t, sid.String())
if err != nil {
return nil, err
}
return sid, nil
}
func BenchmarkEncryptDecryptReader(b *testing.B) {
k := crypto.NewRandomKey()
size := 8 << 20 // 8MiB
rd := RandomReader(23, size)
b.ResetTimer()
b.SetBytes(int64(size))
buf := bytes.NewBuffer(nil)
for i := 0; i < b.N; i++ {
rd.Seek(0, 0)
buf.Reset()
wr := crypto.EncryptTo(k, buf)
_, err := io.Copy(wr, rd)
OK(b, err)
OK(b, wr.Close())
r, err := crypto.DecryptFrom(k, buf)
OK(b, err)
_, err = io.Copy(ioutil.Discard, r)
OK(b, err)
}
}
// CreateEncryptedBlob returns a BlobWriter that encrypts and saves the data
// written to it in the backend. After Close() was called, ID() returns the
// backend.ID.
func (r *Repository) CreateEncryptedBlob(t backend.Type) (*BlobWriter, error) {
blob, err := r.be.Create()
if err != nil {
return nil, err
}
// hash
hw := backend.NewHashingWriter(blob, sha256.New())
// encrypt blob
ewr := crypto.EncryptTo(r.key, hw)
return &BlobWriter{t: t, blob: blob, hw: hw, ewr: ewr}, nil
}
func BenchmarkEncryptWriter(b *testing.B) {
size := 8 << 20 // 8MiB
k := crypto.NewRandomKey()
b.ResetTimer()
b.SetBytes(int64(size))
for i := 0; i < b.N; i++ {
rd := RandomLimitReader(23, size)
wr := crypto.EncryptTo(k, ioutil.Discard)
n, err := io.Copy(wr, rd)
OK(b, err)
OK(b, wr.Close())
Assert(b, n == int64(size),
"not enough bytes writter: want %d, got %d", size, n)
}
}
// SaveJSONUnpacked serialises item as JSON and encrypts and saves it in the
// backend as type t, without a pack. It returns the storage hash.
func (r *Repository) SaveJSONUnpacked(t backend.Type, item interface{}) (backend.ID, error) {
// create file
blob, err := r.be.Create()
if err != nil {
return backend.ID{}, err
}
debug.Log("Repo.SaveJSONUnpacked", "create new blob %v", t)
// hash
hw := backend.NewHashingWriter(blob, sha256.New())
// encrypt blob
ewr := crypto.EncryptTo(r.key, hw)
enc := json.NewEncoder(ewr)
err = enc.Encode(item)
if err != nil {
return backend.ID{}, fmt.Errorf("json.Encode: %v", err)
}
err = ewr.Close()
if err != nil {
return backend.ID{}, err
}
// finalize blob in the backend
hash := hw.Sum(nil)
sid := backend.ID{}
copy(sid[:], hash)
err = blob.Finalize(t, sid.String())
if err != nil {
debug.Log("Repo.SaveJSONUnpacked", "error saving blob %v as %v: %v", t, sid, err)
return backend.ID{}, err
}
debug.Log("Repo.SaveJSONUnpacked", "new blob %v saved as %v", t, sid)
return sid, nil
}
// SaveIndex saves all new packs in the index in the backend, returned is the
// storage ID.
func (r *Repository) SaveIndex() (backend.ID, error) {
debug.Log("Repo.SaveIndex", "Saving index")
// create blob
blob, err := r.be.Create()
if err != nil {
return backend.ID{}, err
}
debug.Log("Repo.SaveIndex", "create new pack %p", blob)
// hash
hw := backend.NewHashingWriter(blob, sha256.New())
// encrypt blob
ewr := crypto.EncryptTo(r.key, hw)
err = r.idx.Encode(ewr)
if err != nil {
return backend.ID{}, err
}
err = ewr.Close()
if err != nil {
return backend.ID{}, err
}
// finalize blob in the backend
sid := backend.ID{}
copy(sid[:], hw.Sum(nil))
err = blob.Finalize(backend.Index, sid.String())
if err != nil {
return backend.ID{}, err
}
debug.Log("Repo.SaveIndex", "Saved index as %v", sid.Str())
return sid, nil
}
// Finalize writes the header for all added blobs and finalizes the pack.
// Returned are the complete number of bytes written, including the header.
// After Finalize() has finished, the ID of this pack can be obtained by
// calling ID().
func (p *Packer) Finalize() (bytesWritten uint, err error) {
p.m.Lock()
defer p.m.Unlock()
bytesWritten = p.bytes
// create writer to encrypt header
wr := crypto.EncryptTo(p.k, p.hw)
bytesHeader, err := p.writeHeader(wr)
if err != nil {
wr.Close()
return bytesWritten + bytesHeader, err
}
bytesWritten += bytesHeader
// finalize encrypted header
err = wr.Close()
if err != nil {
return bytesWritten, err
}
// account for crypto overhead
bytesWritten += crypto.Extension
// write length
err = binary.Write(p.hw, binary.LittleEndian, uint32(uint(len(p.blobs))*entrySize+crypto.Extension))
if err != nil {
return bytesWritten, err
}
bytesWritten += uint(binary.Size(uint32(0)))
p.bytes = uint(bytesWritten)
return bytesWritten, nil
}
