// checks request code and calls corresponding function
func (st StorageNode) handleCode(uuid uint64, code uint8, conn net.Conn, r *bufio.Reader, w *bufio.Writer) {
switch code {
case 1: // client is requesting a file
hash := utils.ReadHashAsString(r)
fmt.Println("Hash received: " + hash)
// check if file exists
var sendcode uint8
fp := st.getPath() + "files/" + hash
if _, err := os.Stat(fp); err == nil {
fmt.Println("File with hash " + hash + " exists")
sendcode = 3 // file available code
err := w.WriteByte(sendcode) // let client know
if err != nil {
panic(err)
}
w.Flush()
// send the file
fmt.Println("Sending file " + hash)
utils.SendFile(conn, w, fp)
} else {
fmt.Println("File with hash " + hash + " does not exist")
sendcode = 4
err := w.WriteByte(sendcode) // let client know
if err != nil {
panic(err)
}
w.Flush()
}
case 2: // receive file from client
fmt.Println("Receiving file")
hash := utils.ReadHashAsString(r)
output := st.getPath() + "files/" + hash
utils.ReceiveFile(conn, r, output)
fmt.Println("File received; md5 checksum of file is: " + hash)
}
fmt.Println()
conn.Close()
}
func send(r *bufio.Reader, w *bufio.Writer, currentDir string, args []string, thisUser *utils.User) (err error) {
if len(args) < 2 {
return err
}
// Format the file to send (absolute or relative)
filepath := ""
if path.IsAbs(args[1]) { // if we are trying to send an absolute filepath
filepath = args[1]
} else { // we must be sending a relative filepath, so calculate the path
wd, err := os.Getwd()
if err != nil {
return err
}
filepath = path.Join(wd, args[1])
}
// ensure the file is existant locally
src, err := os.Stat(filepath)
if err != nil {
fmt.Println("\"" + filepath + "\" does not exist")
return nil
} else if src.IsDir() {
fmt.Println("\"" + filepath + "\" is a directory, not a file")
return nil
} else {
fmt.Println("Sending: \"" + filepath + "\"")
}
// START SENDCODE BLOCK - tell mdserv we are sending a file
err = w.WriteByte(6)
w.Flush()
if err != nil {
panic(err)
}
// END SENDCODE BLOCK
// Send current dir
w.WriteString(currentDir + "\n")
// Send filename to mdserv
w.WriteString(path.Base(filepath) + "\n")
w.Flush()
// Get fail if file exists already
exists, _ := r.ReadByte()
if exists == 1 {
fmt.Println("Bad send request, check file name again")
return nil
} else if exists == 3 {
fmt.Println("Permission denied")
return nil
} else if exists != 2 {
fmt.Println("Bad reponse from metadata service")
return nil
}
// Encryption or not?
if len(args) >= 3 {
if args[2] != "--protect" && args[2] != "-p" {
fmt.Println("Invalid argument option: \"" + args[2] + "\"")
w.WriteByte(2)
w.Flush()
return nil
}
w.WriteByte(1) // tell mdserv we are encrypting
w.Flush()
users := []utils.User{*thisUser}
// send len of args
w.WriteByte(uint8(len(args) - 3))
w.Flush()
for i := 3; i < len(args); i++ {
w.WriteString(args[i] + "\n")
w.Flush()
uuid, _ := r.ReadString('\n')
uuid = strings.TrimSpace(uuid)
if uuid != "INV" {
var newUser utils.User
newUser.Uuid, _ = strconv.ParseUint(uuid, 10, 64)
// receive the public key for the new user
pubKN, _ := r.ReadString('\n')
pubKE, _ := r.ReadString('\n')
newUser.Pubkey = &rsa.PublicKey{N: big.NewInt(0)}
newUser.Pubkey.N.SetString(strings.TrimSpace(pubKN), 10)
newUser.Pubkey.E, err = strconv.Atoi(strings.TrimSpace(pubKE))
users = append(users, newUser)
}
}
encrypFile := os.TempDir() + "/" + path.Base(filepath)
err = utils.EncryptFile(filepath, encrypFile, users...)
if err != nil {
return err
}
filepath = encrypFile
fmt.Println("File successfully protected")
} else {
w.WriteByte(3) // normal continue
w.Flush()
}
// get hash of the file to send to the stnode and mdserv
hash, err := utils.ComputeMd5(filepath)
if err != nil {
panic(err)
}
//checksum := hex.EncodeToString(hash)
// Send hash to mdserv
err = utils.WriteHash(w, hash)
if err != nil {
return err
}
// See are there stnodes available
avail, _ := r.ReadByte()
var conns net.Conn
for avail != 2 {
// Get details of a storage node if file not exists
protocol, _ := r.ReadString('\n')
nAddress, _ := r.ReadString('\n')
protocol = strings.TrimSpace(protocol)
nAddress = strings.TrimSpace(nAddress)
// connect to stnode
conns, err = net.Dial(protocol, nAddress)
if err != nil {
w.WriteByte(1)
w.Flush()
} else { // successful connection
avail = 3
w.WriteByte(2)
w.Flush()
break
}
avail, _ = r.ReadByte()
}
if avail != 3 {
fmt.Println("There were no stnodes available")
return nil
}
defer conns.Close()
// create a read and write buffer for the connection
ws := bufio.NewWriter(conns)
// tell the stnode we are sending a file
err = ws.WriteByte(2)
if err != nil {
return err
}
// send hash to stnode
err = utils.WriteHash(ws, hash)
if err != nil {
return err
}
// send file to stnode
utils.SendFile(conns, ws, filepath)
// Send success/fail to mdserv to log the file send or not
w.WriteByte(1)
w.Flush()
fmt.Println("Successfully sent file")
// on failure to send a file, print err
return err
}