Exemple #1
0
/**
 * Set a timestamp and calculate a digital signature.  First
 * calculate the SHA1 hash of the pubKey, title, timestamp,
 * and content lines, excluding the terminating CRLF in each
 * case, then encrypt that using the RSA private key supplied.
 *
 * @param key RSAKey whose secret materials are used to sign
 */
func (sl *SignedBList) Sign(skPriv *rsa.PrivateKey) (err error) {

	var (
		digSig, hash []byte
	)

	if sl.DigSig != nil {
		err = ListAlreadySigned
	} else if skPriv == nil {
		err = NilPrivateKey
	} else {
		sl.Timestamp = xu.Timestamp(time.Now().UnixNano())
		hash, err = sl.HashBody()
		if err == nil {
			digSig, err = rsa.SignPKCS1v15(
				rand.Reader, skPriv, crypto.SHA1, hash)
			if err == nil {
				sl.DigSig = digSig
			}
		}
		if err != nil {
			sl.Timestamp = 0 // restore to default
		}
	}
	return
}
func (s *XLSuite) TestChunkList(c *C) {
	if VERBOSITY > 0 {
		fmt.Println("TEST_CHUNK_LIST")
	}
	rng := xr.MakeSimpleRNG()

	dataLen := 1 + rng.Intn(3*MAX_DATA_BYTES)
	data := make([]byte, dataLen)
	rng.NextBytes(data)

	reader := bytes.NewReader(data)
	d := sha1.New()
	d.Write(data)
	datum := d.Sum(nil)
	nodeID, err := xi.NewNodeID(datum)
	c.Assert(err, IsNil)

	skPriv, err := rsa.GenerateKey(rand.Reader, 1024) // cheap key

	sk := &skPriv.PublicKey
	title := rng.NextFileName(8)
	timestamp := xu.Timestamp(rng.Int63())

	cl, err := NewChunkList(sk, title, timestamp, reader, int64(dataLen), datum, nil)
	c.Assert(err, IsNil)
	c.Assert(cl, NotNil)

	chunkCount := uint((dataLen + MAX_DATA_BYTES - 1) / MAX_DATA_BYTES)
	c.Assert(cl.Size(), Equals, chunkCount)

	for i := uint(0); i < chunkCount; i++ {
		actual, err := cl.HashItem(i)
		c.Assert(err, IsNil)
		expected := s.calculateChunkHash(c, i, datum, data)
		// DEBUG
		fmt.Printf("chunk %d hash\n    actual   %x\n    expected %x\n",
			i, actual, expected)
		// END
		//c.Assert(actual, DeepEquals, expected)

		// compare with result of calculation in NewChunk -----------
		var chunk *Chunk
		var slice []byte
		if i == chunkCount-1 {
			slice = data[i*MAX_DATA_BYTES:]
		} else {
			slice = data[i*MAX_DATA_BYTES : (i+1)*MAX_DATA_BYTES]
		}

		chunk, err = NewChunk(nodeID, uint32(i), slice)
		c.Assert(err, Equals, nil)
		c.Assert(chunk.GetChunkHash(), DeepEquals, expected)
	}

}
func (s *XLSuite) TestChunkListAssyDisassy(c *C) {
	if VERBOSITY > 0 {
		fmt.Println("TEST_CHUNK_LIST_ASSY_DISASSY")
	}
	rng := xr.MakeSimpleRNG()

	// make a slice 3 to 7 chunks long, fill with random-ish data ---
	chunkCount := 3 + rng.Intn(5) // so 3 to 7, inclusive
	lastChunkLen := 1 + rng.Intn(MAX_DATA_BYTES-1)
	dataLen := (chunkCount-1)*MAX_DATA_BYTES + lastChunkLen
	data := make([]byte, dataLen)
	rng.NextBytes(data)

	// calculate datum, the SHA hash of the data --------------------
	//d := sha3.NewKeccak256()
	d := sha1.New()
	d.Write(data)
	hash := d.Sum(nil)
	datum, err := xi.NewNodeID(hash)
	c.Assert(err, IsNil)

	// create tmp if it doesn't exist -------------------------------
	found, err := xf.PathExists("tmp")
	c.Assert(err, IsNil)
	if !found {
		err = os.MkdirAll("tmp", 0755)
		c.Assert(err, IsNil)
	}

	// create scratch subdir with unique name -----------------------
	var pathToU string
	for {
		dirName := rng.NextFileName(8)
		pathToU = path.Join("tmp", dirName)
		found, err = xf.PathExists(pathToU)
		c.Assert(err, IsNil)
		if !found {
			break
		}
	}

	// create a FLAT uDir at that point -----------------------------
	myU, err := u.New(pathToU, u.DIR_FLAT, 0) // 0 means default perm
	c.Assert(err, IsNil)

	// write the test data into uDir --------------------------------
	bytesWritten, key, err := myU.PutData(data, datum.Value())
	c.Assert(err, IsNil)
	c.Assert(bytes.Equal(datum.Value(), key), Equals, true)
	c.Assert(bytesWritten, Equals, int64(dataLen))

	skPriv, err := rsa.GenerateKey(rand.Reader, 1024) // cheap key
	sk := &skPriv.PublicKey
	c.Assert(err, IsNil)
	c.Assert(skPriv, NotNil)

	// Verify the file is present in uDir ---------------------------
	// (yes this is a test of uDir logic but these are early days ---
	// XXX uDir.Exist(arg) - arg should be []byte, no string
	keyStr := hex.EncodeToString(key)
	found, err = myU.HexKeyExists(keyStr)
	c.Assert(err, IsNil)
	c.Assert(found, Equals, true)

	// use the data file to build a chunkList, writing the chunks ---
	title := rng.NextFileName(8)
	now := xu.Timestamp(time.Now().UnixNano())

	// make a reader --------------------------------------
	pathToData, err := myU.GetPathForHexKey(keyStr)
	c.Assert(err, IsNil)
	reader, err := os.Open(pathToData) // open for read only
	c.Assert(err, IsNil)
	defer reader.Close()

	chunkList, err := NewChunkList(sk, title, now, reader, int64(dataLen), key, myU)
	c.Assert(err, IsNil)
	err = chunkList.Sign(skPriv)
	c.Assert(err, IsNil)

	digSig, err := chunkList.GetDigSig()
	c.Assert(err, IsNil)
	c.Assert(bytes.Equal(digSig, chunkList.digSig), Equals, true)

	err = chunkList.Verify()
	c.Assert(err, IsNil)

	// REBUILD AND CHECK --------------------------------------------
	// rebuild the complete file from the chunkList and files present
	// in myU

	u2, err := u.New(pathToU, u.DIR_FLAT, 0) // 0 means default perm
	c.Assert(err, IsNil)

	var data2 []byte // should become copy of original
	count := chunkList.Size()
	for i := uint(0); i < count; i++ {
		chunkHash, err := chunkList.HashItem(i)
		c.Assert(err, IsNil)
		c.Assert(chunkHash, NotNil)
		var raw []byte
		// THIS IS A CHUNK, and so has a header, possibly some
		// padding, and then its own hash :-).  Need to verify
		// and discard the last, then drop the padding.
		// CORRECTION: hash should NOT have been written to disk
		raw, err = u2.GetData(chunkHash)
		c.Assert(err, IsNil)

		chunk := &Chunk{packet: raw}
		ndx := chunk.GetIndex()
		c.Assert(ndx, Equals, uint32(i))
		rawLen := uint32(len(raw))
		dataLen := chunk.GetDataLen()

		//fmt.Printf("chunk %2d: index is %8d\n", i, ndx)
		//fmt.Printf("          len raw is %6d (%4x)\n", rawLen, rawLen)
		//fmt.Printf("          dataLen is %6d (%4x)\n", dataLen, dataLen)

		// if this isn't true, we get a panic
		c.Assert(dataLen < rawLen, Equals, true)
		payload := chunk.GetData()

		data2 = append(data2, payload...)
	}
	// verify that the content key of the rebuilt file is identical to
	// that of the original

	//d2D := sha3.NewKeccak256()
	d2D := sha1.New()
	d2D.Write(data2)
	hash2 := d2D.Sum(nil)
	datum2, err := xi.NewNodeID(hash2)
	c.Assert(err, IsNil)
	// DEBUG
	//fmt.Printf("datum:  %x\ndatum2: %x\n", datum.Value(), datum2.Value())
	//fmt.Printf("data: %x\ndata2: %x\n", data, data2)
	// END
	c.Assert(bytes.Equal(datum.Value(), datum2.Value()), Equals, true)

	// presumably pure pedantry: verify that the file contents are
	// also equal

	c.Assert(bytes.Equal(data, data2), Equals, true)
}