* Generate RSA key and spawn SFTP server for test

sftp_test.go

diff --git a/sftp_test.go b/sftp_test.go
index 8c48652..839a19d 100644
--- a/sftp_test.go
+++ b/sftp_test.go
@@ -14,11 +14,18 @@
 package afero
 
 import (
-	"os"
-	"io/ioutil"
 	"testing"
-
-	"github.com/spf13/afero"
+	"os"
+	"log"
+	"fmt"
+	"net"
+	"flag"
+	"time"
+	"io/ioutil"
+	"crypto/rsa"
+	_rand "crypto/rand"
+	"encoding/pem"
+	"crypto/x509"
 
 	"golang.org/x/crypto/ssh"
 	"github.com/pkg/sftp"
@@ -30,7 +37,7 @@
 	sftpc  *sftp.Client
 }
 
-func SftpConnect(user string, host string) (*SftpFsContext, error) {
+func SftpConnect(user, password, host string) (*SftpFsContext, error) {
 	pemBytes, err := ioutil.ReadFile(os.Getenv("HOME") + "/.ssh/id_rsa")
 	if err != nil {
 		return nil,err
@@ -44,6 +51,7 @@
 	sshcfg := &ssh.ClientConfig{
 		User: user,
 		Auth: []ssh.AuthMethod{
+			ssh.Password(password),
 			ssh.PublicKeys(signer),
 		},
 	}
@@ -73,20 +81,194 @@
 	return nil
 }
 
+func RunSftpServer() {
+	var (
+		readOnly      bool
+		debugLevelStr string
+		debugLevel    int
+		debugStderr   bool
+		rootDir       string
+	)
+
+	flag.BoolVar(&readOnly, "R", false, "read-only server")
+	flag.BoolVar(&debugStderr, "e", false, "debug to stderr")
+	flag.StringVar(&debugLevelStr, "l", "none", "debug level")
+	flag.StringVar(&rootDir, "root", ".", "root directory")
+	flag.Parse()
+
+	debugStream := ioutil.Discard
+	if debugStderr {
+		debugStream = os.Stderr
+		debugLevel = 1
+	}
+
+	// An SSH server is represented by a ServerConfig, which holds
+	// certificate details and handles authentication of ServerConns.
+	config := &ssh.ServerConfig{
+		PasswordCallback: func(c ssh.ConnMetadata, pass []byte) (*ssh.Permissions, error) {
+			// Should use constant-time compare (or better, salt+hash) in
+			// a production setting.
+			fmt.Fprintf(debugStream, "Login: %s\n", c.User())
+			if c.User() == "test" && string(pass) == "test" {
+				return nil, nil
+			}
+			return nil, fmt.Errorf("password rejected for %q", c.User())
+		},
+	}
+
+	privateBytes, err := ioutil.ReadFile("./test/id_rsa")
+	if err != nil {
+		log.Fatal("Failed to load private key", err)
+	}
+
+	private, err := ssh.ParsePrivateKey(privateBytes)
+	if err != nil {
+		log.Fatal("Failed to parse private key", err)
+	}
+
+	config.AddHostKey(private)
+
+	// Once a ServerConfig has been configured, connections can be
+	// accepted.
+	listener, err := net.Listen("tcp", "0.0.0.0:2022")
+	if err != nil {
+		log.Fatal("failed to listen for connection", err)
+	}
+	fmt.Printf("Listening on %v\n", listener.Addr())
+
+	nConn, err := listener.Accept()
+	if err != nil {
+		log.Fatal("failed to accept incoming connection", err)
+	}
+
+	// Before use, a handshake must be performed on the incoming
+	// net.Conn.
+	_, chans, reqs, err := ssh.NewServerConn(nConn, config)
+	if err != nil {
+		log.Fatal("failed to handshake", err)
+	}
+	fmt.Fprintf(debugStream, "SSH server established\n")
+
+	// The incoming Request channel must be serviced.
+	go ssh.DiscardRequests(reqs)
+
+	// Service the incoming Channel channel.
+	for newChannel := range chans {
+		// Channels have a type, depending on the application level
+		// protocol intended. In the case of an SFTP session, this is "subsystem"
+		// with a payload string of "<length=4>sftp"
+		fmt.Fprintf(debugStream, "Incoming channel: %s\n", newChannel.ChannelType())
+		if newChannel.ChannelType() != "session" {
+			newChannel.Reject(ssh.UnknownChannelType, "unknown channel type")
+			fmt.Fprintf(debugStream, "Unknown channel type: %s\n", newChannel.ChannelType())
+			continue
+		}
+		channel, requests, err := newChannel.Accept()
+		if err != nil {
+			log.Fatal("could not accept channel.", err)
+		}
+		fmt.Fprintf(debugStream, "Channel accepted\n")
+
+		// Sessions have out-of-band requests such as "shell",
+		// "pty-req" and "env".  Here we handle only the
+		// "subsystem" request.
+		go func(in <-chan *ssh.Request) {
+			for req := range in {
+				fmt.Fprintf(debugStream, "Request: %v\n", req.Type)
+				ok := false
+				switch req.Type {
+				case "subsystem":
+					fmt.Fprintf(debugStream, "Subsystem: %s\n", req.Payload[4:])
+					if string(req.Payload[4:]) == "sftp" {
+						ok = true
+					}
+				}
+				fmt.Fprintf(debugStream, " - accepted: %v\n", ok)
+				req.Reply(ok, nil)
+			}
+		}(requests)
+
+		server, err := sftp.NewServer(channel, channel, debugStream, debugLevel, readOnly, rootDir)
+		if err != nil {
+			log.Fatal(err)
+		}
+		if err := server.Serve(); err != nil {
+			log.Fatal("sftp server completed with error:", err)
+		}
+	}
+}
+
+
+// MakeSSHKeyPair make a pair of public and private keys for SSH access.
+// Public key is encoded in the format for inclusion in an OpenSSH authorized_keys file.
+// Private Key generated is PEM encoded
+func MakeSSHKeyPair(bits int, pubKeyPath, privateKeyPath string) error {
+	privateKey, err := rsa.GenerateKey(_rand.Reader, bits)
+	if err != nil {
+		return err
+	}
+
+	// generate and write private key as PEM
+	privateKeyFile, err := os.Create(privateKeyPath)
+	defer privateKeyFile.Close()
+	if err != nil {
+		return err
+	}
+
+	privateKeyPEM := &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(privateKey)}
+	if err := pem.Encode(privateKeyFile, privateKeyPEM); err != nil {
+		return err
+	}
+
+	// generate and write public key
+	pub, err := ssh.NewPublicKey(&privateKey.PublicKey)
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(pubKeyPath, ssh.MarshalAuthorizedKey(pub), 0655)
+}
+
 func TestSftpCreate(t *testing.T) {
-	ctx, err := SftpConnect("user", "host:port")
+	os.Mkdir("./test", 0777)
+	MakeSSHKeyPair(1024, "./test/id_rsa.pub", "./test/id_rsa")
+
+	go RunSftpServer()
+	time.Sleep(2 * time.Second)
+
+	ctx, err := SftpConnect("test", "test", "localhost:2022")
 	if err != nil {
 		t.Fatal(err)
 	}
 	defer ctx.Disconnect()
 
-	var AppFs afero.Fs = afero.SftpFs{
+	var AppFs Fs = SftpFs{
 		SftpClient: ctx.sftpc,
 	}
 
-	file, err := AppFs.Create("aferoSftpFsTestFile")
+	AppFs.MkdirAll("test/dir1/dir2/dir3", os.FileMode(0777))
+	AppFs.Mkdir("test/foo", os.FileMode(0000))
+	AppFs.Mkdir("test/bar", os.FileMode(0777))
+
+	file, err := AppFs.Create("file1")
 	if err != nil {
 		t.Error(err)
 	}
 	defer file.Close()
+
+	file.Write([]byte("whohoo\n"))
+	file.WriteString("sdsdsdsdsddssdsd")
+
+	f1, err := AppFs.Open("file1")
+	if err != nil {
+		log.Fatalf("open: %v", err)
+	}
+	defer f1.Close()
+
+	b := make([]byte, 100)
+
+	_, err = f1.Read(b)
+	fmt.Println(string(b))
+
+	AppFs.Remove("test")
 }