v/vlib/net/ftp/ftp.v

310 lines
4.6 KiB
V

/*
basic ftp module
RFC-959
https://tools.ietf.org/html/rfc959
Methods:
ftp.connect(host)
ftp.login(user, passw)
pwd := ftp.pwd()
ftp.cd(folder)
dtp := ftp.pasv()
ftp.dir()
ftp.get(file)
dtp.read()
dtp.close()
ftp.close()
*/
module ftp
import net
const (
Connected = 220
SpecifyPassword = 331
LoggedIn = 230
LoginFirst = 503
Anonymous = 530
OpenDataConnection = 150
CloseDataConnection = 226
CommandOk = 200
Denied = 550
PassiveMode = 227
Complete = 226
)
struct DTP {
mut:
sock net.Socket
ip string
port int
}
fn (dtp DTP) read() []byte {
mut data := []byte
for {
buf, len := dtp.sock.recv(1024)
if len == 0 { break }
for i in 0..len {
data << buf[i]
}
unsafe { free(buf) }
}
return data
}
fn (dtp DTP) close() {
dtp.sock.close() or {}
}
struct FTP {
mut:
sock net.Socket
buffer_size int
}
pub fn new() FTP {
mut f := FTP{}
f.buffer_size = 1024
return f
}
fn (ftp FTP) write(data string) ?int {
$if debug {
println('FTP.v >>> $data')
}
n := ftp.sock.send_string('$data\r\n') or {
return error('Cannot send data')
}
return n
}
fn (ftp FTP) read() (int, string) {
mut data := ftp.sock.read_line()
$if debug {
println('FTP.v <<< $data')
}
if data.len < 5 {
return 0, ''
}
code := data[..3].int()
if data[3] == `-` {
for {
data = ftp.sock.read_line()
if data[..3].int() == code && data[3] != `-` {
break
}
}
}
return code, data
}
pub fn (ftp mut FTP) connect(ip string) bool {
sock := net.dial(ip, 21) or {
return false
}
ftp.sock = sock
code, _ := ftp.read()
if code == Connected {
return true
}
return false
}
pub fn (ftp FTP) login(user, passwd string) bool {
ftp.write('USER $user') or {
$if debug {
println('ERROR sending user')
}
return false
}
mut data := ''
mut code := 0
code, data = ftp.read()
if code == LoggedIn {
return true
}
if code != SpecifyPassword {
return false
}
ftp.write('PASS $passwd') or {
$if debug {
println('ERROR sending password')
}
return false
}
code, data = ftp.read()
if code == LoggedIn {
return true
}
return false
}
pub fn (ftp FTP) close() {
send_quit := 'QUIT\r\n'
ftp.sock.send_string(send_quit) or {}
ftp.sock.close() or {}
}
pub fn (ftp FTP) pwd() string {
ftp.write('PWD') or {
return ''
}
_, data := ftp.read()
spl := data.split('"')
if spl.len >= 2 {
return spl[1]
}
return data
}
pub fn (ftp FTP) cd(dir string) {
ftp.write('CWD $dir') or { return }
mut code, mut data := ftp.read()
match code {
Denied {
$if debug {
println('CD $dir denied!')
}
}
Complete {
code, data = ftp.read()
}
else {}
}
$if debug {
println('CD $data')
}
}
fn new_dtp(msg string) ?DTP {
if !is_dtp_message_valid(msg) {
return error('Bad message')
}
ip, port := get_host_ip_from_dtp_message(msg)
sock := net.dial(ip, port) or {
return error('Cannot connect to the data channel')
}
dtp := DTP {
sock: sock
ip: ip
port: port
}
return dtp
}
fn (ftp FTP) pasv() ?DTP {
ftp.write('PASV') or {}
code, data := ftp.read()
$if debug {
println('pass: $data')
}
if code != PassiveMode {
return error('pasive mode not allowed')
}
dtp := new_dtp(data)
return dtp
}
pub fn (ftp FTP) dir() ?[]string {
dtp := ftp.pasv() or {
return error('cannot establish data connection')
}
ftp.write('LIST') or {}
code, _ := ftp.read()
if code == Denied {
return error('LIST denied')
}
if code != OpenDataConnection {
return error('data channel empty')
}
list_dir := dtp.read()
result, _ := ftp.read()
if result != CloseDataConnection {
println('LIST not ok')
}
dtp.close()
mut dir := []string
sdir := string(byteptr(list_dir.data))
for lfile in sdir.split('\n') {
if lfile.len >1 {
spl := lfile.split(' ')
dir << spl[spl.len-1]
}
}
return dir
}
pub fn (ftp FTP) get(file string) ?[]byte {
dtp := ftp.pasv() or {
return error('Cannot stablish data connection')
}
ftp.write('RETR $file') or {}
code, _ := ftp.read()
if code == Denied {
return error('Permission denied')
}
if code != OpenDataConnection {
return error('Data connection not ready')
}
blob := dtp.read()
dtp.close()
return blob
}
fn is_dtp_message_valid(msg string) bool {
// An example of message:
// '227 Entering Passive Mode (209,132,183,61,48,218)'
return msg.contains('(') && msg.contains(')') && msg.contains(',')
}
fn get_host_ip_from_dtp_message(msg string) (string, int) {
mut par_start_idx := -1
mut par_end_idx := -1
for i, c in msg {
if c == `(` {
par_start_idx = i + 1
} else if c == `)` {
par_end_idx = i
}
}
data := msg[par_start_idx..par_end_idx].split(',')
ip := data[0..4].join('.')
port := data[4].int() * 256 + data[5].int()
return ip, port
}