Пример #1
0
// NewUnpacker returns a pointer to Unpacker which can be used to read
// individual Blobs from a pack.
func NewUnpacker(k *crypto.Key, rd io.ReadSeeker) (*Unpacker, error) {
	var err error
	ls := binary.Size(uint32(0))

	// reset to the end to read header length
	_, err = rd.Seek(-int64(ls), 2)
	if err != nil {
		return nil, fmt.Errorf("seeking to read header length failed: %v", err)
	}

	var length uint32
	err = binary.Read(rd, binary.LittleEndian, &length)
	if err != nil {
		return nil, fmt.Errorf("reading header length failed: %v", err)
	}

	// reset to the beginning of the header
	_, err = rd.Seek(-int64(ls)-int64(length), 2)
	if err != nil {
		return nil, fmt.Errorf("seeking to read header length failed: %v", err)
	}

	// read header
	hrd, err := crypto.DecryptFrom(k, io.LimitReader(rd, int64(length)))
	if err != nil {
		return nil, err
	}

	var entries []Blob

	pos := uint(0)
	for {
		e := headerEntry{}
		err = binary.Read(hrd, binary.LittleEndian, &e)
		if err == io.EOF {
			break
		}

		if err != nil {
			return nil, err
		}

		entries = append(entries, Blob{
			Type:   e.Type,
			Length: uint(e.Length),
			ID:     e.ID,
			Offset: pos,
		})

		pos += uint(e.Length)
	}

	p := &Unpacker{
		rd:      rd,
		k:       k,
		Entries: entries,
	}

	return p, nil
}
Пример #2
0
func TestDecryptStreamReader(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 := Random(42, size)
		var err error
		ciphertext := make([]byte, size+crypto.Extension)

		// encrypt with default function
		ciphertext, err = crypto.Encrypt(k, ciphertext, data)
		OK(t, err)
		Assert(t, len(ciphertext) == len(data)+crypto.Extension,
			"wrong number of bytes returned after encryption: expected %d, got %d",
			len(data)+crypto.Extension, len(ciphertext))

		rd, err := crypto.DecryptFrom(k, bytes.NewReader(ciphertext))
		OK(t, err)

		plaintext, err := ioutil.ReadAll(rd)
		OK(t, err)

		Assert(t, bytes.Equal(data, plaintext),
			"wrong plaintext after decryption: expected %02x, got %02x",
			data, plaintext)
	}
}
Пример #3
0
func BenchmarkDecryptReader(b *testing.B) {
	size := 8 << 20 // 8MiB
	buf := Random(23, size)
	k := crypto.NewRandomKey()

	ciphertext := make([]byte, len(buf)+crypto.Extension)
	_, err := crypto.Encrypt(k, ciphertext, buf)
	OK(b, err)

	rd := bytes.NewReader(ciphertext)

	b.ResetTimer()
	b.SetBytes(int64(size))

	for i := 0; i < b.N; i++ {
		rd.Seek(0, 0)
		decRd, err := crypto.DecryptFrom(k, rd)
		OK(b, err)

		_, err = io.Copy(ioutil.Discard, decRd)
		OK(b, err)
	}
}
Пример #4
0
func BenchmarkEncryptDecryptReader(b *testing.B) {
	k := crypto.NewRandomKey()

	size := 8 << 20 // 8MiB

	b.ResetTimer()
	b.SetBytes(int64(size))

	buf := bytes.NewBuffer(nil)
	for i := 0; i < b.N; i++ {
		rd := RandomLimitReader(23, size)
		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)
	}
}