From 0b1f88c1aa86526100ebccebe86e403458beefda Mon Sep 17 00:00:00 2001
From: Vasiliy Tolstov <v.tolstov@selfip.ru>
Date: Tue, 14 Apr 2015 03:14:38 +0300
Subject: [PATCH] initial import

Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>
---
 .gitignore |   1 +
 main.go    | 195 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 server.go  |  20 ++++++
 3 files changed, 216 insertions(+)
 create mode 100644 main.go
 create mode 100644 server.go

diff --git a/.gitignore b/.gitignore
index daf913b..ee87be6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,3 +22,4 @@ _testmain.go
 *.exe
 *.test
 *.prof
+go-ftp
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..d702035
--- /dev/null
+++ b/main.go
@@ -0,0 +1,195 @@
+package main
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+)
+
+func main() {
+	l, err := net.Listen("tcp", ":8021")
+	if err != nil {
+		panic(err)
+
+	}
+	defer l.Close()
+
+	for {
+		conn, err := l.Accept()
+		if err != nil {
+			fmt.Printf(err.Error())
+			continue
+		}
+		go handle(conn)
+	}
+}
+
+func handle(c net.Conn) {
+	defer c.Close()
+	s, err := NewServer(c)
+	if err != nil {
+		fmt.Printf(err.Error())
+	}
+	s.ctrl.PrintfLine("220 %s [%s]", "go-ftp", c.LocalAddr())
+	for {
+		line, err := s.ctrl.ReadLine()
+		if err != nil {
+			fmt.Printf(err.Error())
+			return
+		}
+		parts := strings.Fields(line)
+		cmd := parts[0]
+		params := parts[1:]
+		switch cmd {
+		case "USER":
+			s.cmdServerUser(params)
+		case "PASS":
+			s.cmdServerPass(params)
+		case "PWD":
+			s.cmdServerPwd(params)
+		case "EPSV":
+			s.cmdServerEpsv(params)
+		case "PASV":
+			s.cmdServerPasv(params)
+		case "TYPE":
+			s.cmdServerType(params)
+		case "LIST":
+			s.cmdServerList(params)
+		case "SYST":
+			s.cmdServerSyst(params)
+		case "QUIT":
+			s.cmdServerQuit(params)
+			s.Close()
+			return
+		case "SIZE":
+			s.cmdServerSize(params)
+		case "CWD":
+			s.cmdServerCwd(params)
+		case "RETR":
+			s.cmdServerRetr(params)
+		default:
+			fmt.Printf("%s\n", line)
+		}
+	}
+}
+
+func (s *Conn) cmdServerUser(args []string) {
+	fmt.Printf("cmdServerUser: %s\n", args)
+	s.ctrl.PrintfLine("331 Password required for %s", args[0])
+}
+
+func (s *Conn) cmdServerPass(args []string) {
+	fmt.Printf("cmdServerPass: %s\n", args)
+	s.ctrl.PrintfLine("230 Logged on")
+	//530 Login incorrect.
+}
+
+func (s *Conn) cmdServerPwd(args []string) {
+	fmt.Printf("cmdServerPwd: %s\n", args)
+	s.ctrl.PrintfLine(`257 "/" is current directory.`)
+}
+
+func (s *Conn) cmdServerEpsv(args []string) {
+	fmt.Printf("cmdServerEpsv: %s\n", args)
+	ln, err := net.Listen("tcp4", "37.139.40.30:0")
+	if err != nil {
+
+	}
+	s.ln = ln
+	_, port, _ := net.SplitHostPort(ln.Addr().String())
+	s.ctrl.PrintfLine("229 Entering Extended Passive Mode (|||%s|)", port)
+	go func() {
+		for {
+			conn, err := s.ln.Accept()
+			if err != nil {
+				return
+			}
+			s.data = conn
+		}
+	}()
+}
+
+func (s *Conn) cmdServerType(args []string) {
+	fmt.Printf("cmdServerType: %s\n", args)
+	switch args[0] {
+	default:
+		s.ctrl.PrintfLine("200 Type set to %s", args[0])
+	}
+}
+
+func (s *Conn) cmdServerList(args []string) {
+	fmt.Printf("cmdServerList: %s\n", args)
+	s.ctrl.PrintfLine(`150 Opening data channel for directory listing of "%s"`, args[0])
+	n, err := s.data.Write([]byte("-rw-r--r-- 1 ftp ftp              4 Apr 16  2008 TEST\n"))
+	if err != nil {
+		fmt.Printf(err.Error())
+	}
+	s.data.Close()
+	s.ctrl.PrintfLine(`226 Closing data connection, sent %d bytes`, n)
+	s.ctrl.PrintfLine("226 Transfer complete.")
+}
+
+func (s *Conn) cmdServerSyst(args []string) {
+	fmt.Printf("cmdServerSyst: %s\n", args)
+	s.ctrl.PrintfLine("215 UNIX Type: L8")
+}
+
+func (s *Conn) cmdServerQuit(args []string) {
+	if s.data != nil {
+		s.data.Close()
+	}
+	if s.ln != nil {
+		s.ln.Close()
+	}
+	if s.ctrl != nil {
+		s.ctrl.Close()
+	}
+}
+
+func (s *Conn) cmdServerPasv(args []string) {
+	fmt.Printf("cmdServerPasv: %s\n", args)
+
+	ln, err := net.Listen("tcp4", "37.139.40.30:0")
+	if err != nil {
+
+	}
+	s.ln = ln
+	host, port, _ := net.SplitHostPort(ln.Addr().String())
+	p0, _ := strconv.Atoi(port)
+	p1 := p0 / 256
+	p2 := p0 - p1*256
+	s.ctrl.PrintfLine("227 Entering Passive Mode (%s,%d,%d)", strings.Replace(host, ".", ",", -1), p1, p2)
+	go func() {
+		for {
+			conn, err := s.ln.Accept()
+			if err != nil {
+				return
+			}
+			s.data = conn
+		}
+	}()
+}
+
+func (s *Conn) cmdServerSize(args []string) {
+	fmt.Printf("cmdServerSize: %s\n", args)
+	s.ctrl.PrintfLine("213 %d", len([]byte("test\n")))
+}
+
+func (s *Conn) cmdServerCwd(args []string) {
+	fmt.Printf("cmdServerCwd: %s\n", args)
+	s.ctrl.PrintfLine("250 Okay")
+}
+
+func (s *Conn) cmdServerRetr(args []string) {
+	fmt.Printf("cmdServerRetr: %s\n", args)
+	s.ctrl.PrintfLine(`150 Opening data channel for file contents "%s"`, args[0])
+	n, err := s.data.Write([]byte("test\n"))
+	if err != nil {
+		fmt.Printf(err.Error())
+	}
+	s.data.Close()
+	s.ctrl.PrintfLine(`226 Closing data connection, sent %d bytes`, n)
+	s.ctrl.PrintfLine("226 Transfer complete.")
+
+}
diff --git a/server.go b/server.go
new file mode 100644
index 0000000..06776e5
--- /dev/null
+++ b/server.go
@@ -0,0 +1,20 @@
+package main
+
+import (
+	"net"
+	"net/textproto"
+)
+
+type Conn struct {
+	ctrl *textproto.Conn
+	data net.Conn
+	ln   net.Listener
+}
+
+func (c *Conn) Close() error {
+	return c.ctrl.Close()
+}
+
+func NewServer(c net.Conn) (*Conn, error) {
+	return &Conn{ctrl: textproto.NewConn(c)}, nil
+}