// Copyright (C) 2019-2022  Nicola Murino
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, version 3.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

package ftpd

import (
	"crypto/tls"
	"crypto/x509"
	"errors"
	"fmt"
	"io/fs"
	"net"
	"os"
	"path/filepath"
	"runtime"
	"testing"
	"time"

	"github.com/eikenb/pipeat"
	ftpserver "github.com/fclairamb/ftpserverlib"
	"github.com/pires/go-proxyproto"
	"github.com/sftpgo/sdk"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/drakkan/sftpgo/v2/internal/common"
	"github.com/drakkan/sftpgo/v2/internal/dataprovider"
	"github.com/drakkan/sftpgo/v2/internal/vfs"
)

const (
	ftpsCert = `-----BEGIN CERTIFICATE-----
MIICHTCCAaKgAwIBAgIUHnqw7QnB1Bj9oUsNpdb+ZkFPOxMwCgYIKoZIzj0EAwIw
RTELMAkGA1UEBhMCQVUxEzARBgNVBAgMClNvbWUtU3RhdGUxITAfBgNVBAoMGElu
dGVybmV0IFdpZGdpdHMgUHR5IEx0ZDAeFw0yMDAyMDQwOTUzMDRaFw0zMDAyMDEw
OTUzMDRaMEUxCzAJBgNVBAYTAkFVMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYD
VQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwdjAQBgcqhkjOPQIBBgUrgQQA
IgNiAARCjRMqJ85rzMC998X5z761nJ+xL3bkmGVqWvrJ51t5OxV0v25NsOgR82CA
NXUgvhVYs7vNFN+jxtb2aj6Xg+/2G/BNxkaFspIVCzgWkxiz7XE4lgUwX44FCXZM
3+JeUbKjUzBRMB0GA1UdDgQWBBRhLw+/o3+Z02MI/d4tmaMui9W16jAfBgNVHSME
GDAWgBRhLw+/o3+Z02MI/d4tmaMui9W16jAPBgNVHRMBAf8EBTADAQH/MAoGCCqG
SM49BAMCA2kAMGYCMQDqLt2lm8mE+tGgtjDmtFgdOcI72HSbRQ74D5rYTzgST1rY
/8wTi5xl8TiFUyLMUsICMQC5ViVxdXbhuG7gX6yEqSkMKZICHpO8hqFwOD/uaFVI
dV4vKmHUzwK/eIx+8Ay3neE=
-----END CERTIFICATE-----`
	ftpsKey = `-----BEGIN EC PARAMETERS-----
BgUrgQQAIg==
-----END EC PARAMETERS-----
-----BEGIN EC PRIVATE KEY-----
MIGkAgEBBDCfMNsN6miEE3rVyUPwElfiJSWaR5huPCzUenZOfJT04GAcQdWvEju3
UM2lmBLIXpGgBwYFK4EEACKhZANiAARCjRMqJ85rzMC998X5z761nJ+xL3bkmGVq
WvrJ51t5OxV0v25NsOgR82CANXUgvhVYs7vNFN+jxtb2aj6Xg+/2G/BNxkaFspIV
CzgWkxiz7XE4lgUwX44FCXZM3+JeUbI=
-----END EC PRIVATE KEY-----`
	caCRT = `-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`
	caKey = `-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----`
	caCRL = `-----BEGIN X509 CRL-----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-----END X509 CRL-----`
	client1Crt = `-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`
	client1Key = `-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----`
	// client 2 crt is revoked
	client2Crt = `-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`
	client2Key = `-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----`
)

var (
	configDir = filepath.Join(".", "..", "..")
)

type mockFTPClientContext struct {
	lastDataChannel ftpserver.DataChannel
	remoteIP        string
	localIP         string
}

func (cc mockFTPClientContext) Path() string {
	return ""
}

func (cc mockFTPClientContext) SetPath(name string) {}

func (cc mockFTPClientContext) SetListPath(name string) {}

func (cc mockFTPClientContext) SetDebug(debug bool) {}

func (cc mockFTPClientContext) Debug() bool {
	return false
}

func (cc mockFTPClientContext) ID() uint32 {
	return 1
}

func (cc mockFTPClientContext) RemoteAddr() net.Addr {
	ip := "127.0.0.1"
	if cc.remoteIP != "" {
		ip = cc.remoteIP
	}
	return &net.IPAddr{IP: net.ParseIP(ip)}
}

func (cc mockFTPClientContext) LocalAddr() net.Addr {
	ip := "127.0.0.1"
	if cc.localIP != "" {
		ip = cc.localIP
	}
	return &net.IPAddr{IP: net.ParseIP(ip)}
}

func (cc mockFTPClientContext) GetClientVersion() string {
	return "mock version"
}

func (cc mockFTPClientContext) Close() error {
	return nil
}

func (cc mockFTPClientContext) HasTLSForControl() bool {
	return false
}

func (cc mockFTPClientContext) HasTLSForTransfers() bool {
	return false
}

func (cc mockFTPClientContext) SetTLSRequirement(requirement ftpserver.TLSRequirement) error {
	return nil
}

func (cc mockFTPClientContext) GetLastCommand() string {
	return ""
}

func (cc mockFTPClientContext) GetLastDataChannel() ftpserver.DataChannel {
	return cc.lastDataChannel
}

// MockOsFs mockable OsFs
type MockOsFs struct {
	vfs.Fs
	err                     error
	statErr                 error
	isAtomicUploadSupported bool
}

// Name returns the name for the Fs implementation
func (fs MockOsFs) Name() string {
	return "mockOsFs"
}

// IsUploadResumeSupported returns true if resuming uploads is supported
func (MockOsFs) IsUploadResumeSupported() bool {
	return false
}

// IsAtomicUploadSupported returns true if atomic upload is supported
func (fs MockOsFs) IsAtomicUploadSupported() bool {
	return fs.isAtomicUploadSupported
}

// Stat returns a FileInfo describing the named file
func (fs MockOsFs) Stat(name string) (os.FileInfo, error) {
	if fs.statErr != nil {
		return nil, fs.statErr
	}
	return os.Stat(name)
}

// Lstat returns a FileInfo describing the named file
func (fs MockOsFs) Lstat(name string) (os.FileInfo, error) {
	if fs.statErr != nil {
		return nil, fs.statErr
	}
	return os.Lstat(name)
}

// Remove removes the named file or (empty) directory.
func (fs MockOsFs) Remove(name string, isDir bool) error {
	if fs.err != nil {
		return fs.err
	}
	return os.Remove(name)
}

// Rename renames (moves) source to target
func (fs MockOsFs) Rename(source, target string) error {
	if fs.err != nil {
		return fs.err
	}
	return os.Rename(source, target)
}

func newMockOsFs(err, statErr error, atomicUpload bool, connectionID, rootDir string) vfs.Fs {
	return &MockOsFs{
		Fs:                      vfs.NewOsFs(connectionID, rootDir, ""),
		err:                     err,
		statErr:                 statErr,
		isAtomicUploadSupported: atomicUpload,
	}
}

func TestInitialization(t *testing.T) {
	oldMgr := certMgr
	certMgr = nil

	binding := Binding{
		Port: 2121,
	}
	c := &Configuration{
		Bindings:           []Binding{binding},
		CertificateFile:    "acert",
		CertificateKeyFile: "akey",
	}
	assert.False(t, binding.HasProxy())
	assert.Equal(t, "Disabled", binding.GetTLSDescription())
	err := c.Initialize(configDir)
	assert.Error(t, err)
	c.CertificateFile = ""
	c.CertificateKeyFile = ""
	c.BannerFile = "afile"
	server := NewServer(c, configDir, binding, 0)
	assert.Equal(t, "", server.initialMsg)
	_, err = server.GetTLSConfig()
	assert.Error(t, err)

	binding.TLSMode = 1
	server = NewServer(c, configDir, binding, 0)
	_, err = server.GetSettings()
	assert.Error(t, err)

	binding.PassiveConnectionsSecurity = 100
	binding.ActiveConnectionsSecurity = 100
	server = NewServer(c, configDir, binding, 0)
	_, err = server.GetSettings()
	if assert.Error(t, err) {
		assert.Contains(t, err.Error(), "invalid passive_connections_security")
	}
	binding.PassiveConnectionsSecurity = 1
	server = NewServer(c, configDir, binding, 0)
	_, err = server.GetSettings()
	if assert.Error(t, err) {
		assert.Contains(t, err.Error(), "invalid active_connections_security")
	}
	binding = Binding{
		Port:           2121,
		ForcePassiveIP: "192.168.1",
	}
	server = NewServer(c, configDir, binding, 0)
	_, err = server.GetSettings()
	if assert.Error(t, err) {
		assert.Contains(t, err.Error(), "is not valid")
	}

	binding.ForcePassiveIP = "::ffff:192.168.89.9"
	err = binding.checkPassiveIP()
	assert.NoError(t, err)
	assert.Equal(t, "192.168.89.9", binding.ForcePassiveIP)

	binding.ForcePassiveIP = "::1"
	err = binding.checkPassiveIP()
	if assert.Error(t, err) {
		assert.Contains(t, err.Error(), "is not a valid IPv4 address")
	}

	err = ReloadCertificateMgr()
	assert.NoError(t, err)

	certMgr = oldMgr

	binding = Binding{
		Port:           2121,
		ClientAuthType: 1,
	}
	server = NewServer(c, configDir, binding, 0)
	cfg, err := server.GetTLSConfig()
	assert.NoError(t, err)
	assert.Equal(t, tls.RequireAndVerifyClientCert, cfg.ClientAuth)
}

func TestServerGetSettings(t *testing.T) {
	oldConfig := common.Config

	binding := Binding{
		Port:             2121,
		ApplyProxyConfig: true,
	}
	c := &Configuration{
		Bindings: []Binding{binding},
		PassivePortRange: PortRange{
			Start: 10000,
			End:   11000,
		},
	}
	assert.False(t, binding.HasProxy())
	server := NewServer(c, configDir, binding, 0)
	settings, err := server.GetSettings()
	assert.NoError(t, err)
	assert.Equal(t, 10000, settings.PassiveTransferPortRange.Start)
	assert.Equal(t, 11000, settings.PassiveTransferPortRange.End)

	common.Config.ProxyProtocol = 1
	common.Config.ProxyAllowed = []string{"invalid"}
	assert.True(t, binding.HasProxy())
	_, err = server.GetSettings()
	assert.Error(t, err)
	server.binding.Port = 8021
	_, err = server.GetSettings()
	assert.Error(t, err)

	assert.Equal(t, "Plain and explicit", binding.GetTLSDescription())

	binding.TLSMode = 1
	assert.Equal(t, "Explicit required", binding.GetTLSDescription())

	binding.TLSMode = 2
	assert.Equal(t, "Implicit", binding.GetTLSDescription())

	certPath := filepath.Join(os.TempDir(), "test.crt")
	keyPath := filepath.Join(os.TempDir(), "test.key")
	err = os.WriteFile(certPath, []byte(ftpsCert), os.ModePerm)
	assert.NoError(t, err)
	err = os.WriteFile(keyPath, []byte(ftpsKey), os.ModePerm)
	assert.NoError(t, err)

	common.Config.ProxyAllowed = nil
	c.CertificateFile = certPath
	c.CertificateKeyFile = keyPath
	server = NewServer(c, configDir, binding, 0)
	server.binding.Port = 9021
	settings, err = server.GetSettings()
	assert.NoError(t, err)
	assert.NotNil(t, settings.Listener)

	listener, err := net.Listen("tcp", ":0")
	assert.NoError(t, err)
	listener, err = server.WrapPassiveListener(listener)
	assert.NoError(t, err)

	_, ok := listener.(*proxyproto.Listener)
	assert.True(t, ok)

	err = os.Remove(certPath)
	assert.NoError(t, err)
	err = os.Remove(keyPath)
	assert.NoError(t, err)

	common.Config = oldConfig
}

func TestUserInvalidParams(t *testing.T) {
	u := dataprovider.User{
		BaseUser: sdk.BaseUser{
			HomeDir: "invalid",
		},
	}
	binding := Binding{
		Port: 2121,
	}
	c := &Configuration{
		Bindings: []Binding{binding},
		PassivePortRange: PortRange{
			Start: 10000,
			End:   11000,
		},
	}
	server := NewServer(c, configDir, binding, 3)
	_, err := server.validateUser(u, mockFTPClientContext{}, dataprovider.LoginMethodPassword)
	assert.Error(t, err)

	u.Username = "a"
	u.HomeDir = filepath.Clean(os.TempDir())
	subDir := "subdir"
	mappedPath1 := filepath.Join(os.TempDir(), "vdir1")
	vdirPath1 := "/vdir1"
	mappedPath2 := filepath.Join(os.TempDir(), "vdir1", subDir)
	vdirPath2 := "/vdir2"
	u.VirtualFolders = append(u.VirtualFolders, vfs.VirtualFolder{
		BaseVirtualFolder: vfs.BaseVirtualFolder{
			MappedPath: mappedPath1,
		},
		VirtualPath: vdirPath1,
	})
	u.VirtualFolders = append(u.VirtualFolders, vfs.VirtualFolder{
		BaseVirtualFolder: vfs.BaseVirtualFolder{
			MappedPath: mappedPath2,
		},
		VirtualPath: vdirPath2,
	})
	_, err = server.validateUser(u, mockFTPClientContext{}, dataprovider.LoginMethodPassword)
	assert.Error(t, err)
	u.VirtualFolders = nil
	_, err = server.validateUser(u, mockFTPClientContext{}, dataprovider.LoginMethodPassword)
	assert.Error(t, err)
}

func TestFTPMode(t *testing.T) {
	connection := &Connection{
		BaseConnection: common.NewBaseConnection("", common.ProtocolFTP, "", "", dataprovider.User{}),
	}
	assert.Empty(t, connection.getFTPMode())
	connection.clientContext = mockFTPClientContext{lastDataChannel: ftpserver.DataChannelActive}
	assert.Equal(t, "active", connection.getFTPMode())
	connection.clientContext = mockFTPClientContext{lastDataChannel: ftpserver.DataChannelPassive}
	assert.Equal(t, "passive", connection.getFTPMode())
	connection.clientContext = mockFTPClientContext{lastDataChannel: 0}
	assert.Empty(t, connection.getFTPMode())
}

func TestClientVersion(t *testing.T) {
	mockCC := mockFTPClientContext{}
	connID := fmt.Sprintf("2_%v", mockCC.ID())
	user := dataprovider.User{}
	connection := &Connection{
		BaseConnection: common.NewBaseConnection(connID, common.ProtocolFTP, "", "", user),
		clientContext:  mockCC,
	}
	err := common.Connections.Add(connection)
	assert.NoError(t, err)
	stats := common.Connections.GetStats()
	if assert.Len(t, stats, 1) {
		assert.Equal(t, "mock version", stats[0].ClientVersion)
		common.Connections.Remove(connection.GetID())
	}
	assert.Len(t, common.Connections.GetStats(), 0)
}

func TestDriverMethodsNotImplemented(t *testing.T) {
	mockCC := mockFTPClientContext{}
	connID := fmt.Sprintf("2_%v", mockCC.ID())
	user := dataprovider.User{}
	connection := &Connection{
		BaseConnection: common.NewBaseConnection(connID, common.ProtocolFTP, "", "", user),
		clientContext:  mockCC,
	}
	_, err := connection.Create("")
	assert.EqualError(t, err, errNotImplemented.Error())
	err = connection.MkdirAll("", os.ModePerm)
	assert.EqualError(t, err, errNotImplemented.Error())
	_, err = connection.Open("")
	assert.EqualError(t, err, errNotImplemented.Error())
	_, err = connection.OpenFile("", 0, os.ModePerm)
	assert.EqualError(t, err, errNotImplemented.Error())
	err = connection.RemoveAll("")
	assert.EqualError(t, err, errNotImplemented.Error())
	assert.Equal(t, connection.GetID(), connection.Name())
}

func TestResolvePathErrors(t *testing.T) {
	user := dataprovider.User{
		BaseUser: sdk.BaseUser{
			HomeDir: "invalid",
		},
	}
	user.Permissions = make(map[string][]string)
	user.Permissions["/"] = []string{dataprovider.PermAny}
	mockCC := mockFTPClientContext{}
	connID := fmt.Sprintf("%v", mockCC.ID())
	connection := &Connection{
		BaseConnection: common.NewBaseConnection(connID, common.ProtocolFTP, "", "", user),
		clientContext:  mockCC,
	}
	err := connection.Mkdir("", os.ModePerm)
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	err = connection.Remove("")
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	err = connection.RemoveDir("")
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	err = connection.Rename("", "")
	assert.ErrorIs(t, err, common.ErrOpUnsupported)
	err = connection.Symlink("", "")
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	_, err = connection.Stat("")
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	err = connection.Chmod("", os.ModePerm)
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	err = connection.Chtimes("", time.Now(), time.Now())
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	_, err = connection.ReadDir("")
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	_, err = connection.GetHandle("", 0, 0)
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
	_, err = connection.GetAvailableSpace("")
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrGenericFailure.Error())
	}
}

func TestUploadFileStatError(t *testing.T) {
	if runtime.GOOS == "windows" {
		t.Skip("this test is not available on Windows")
	}
	user := dataprovider.User{
		BaseUser: sdk.BaseUser{
			Username: "user",
			HomeDir:  filepath.Clean(os.TempDir()),
		},
	}
	user.Permissions = make(map[string][]string)
	user.Permissions["/"] = []string{dataprovider.PermAny}
	mockCC := mockFTPClientContext{}
	connID := fmt.Sprintf("%v", mockCC.ID())
	fs := vfs.NewOsFs(connID, user.HomeDir, "")
	connection := &Connection{
		BaseConnection: common.NewBaseConnection(connID, common.ProtocolFTP, "", "", user),
		clientContext:  mockCC,
	}
	testFile := filepath.Join(user.HomeDir, "test", "testfile")
	err := os.MkdirAll(filepath.Dir(testFile), os.ModePerm)
	assert.NoError(t, err)
	err = os.WriteFile(testFile, []byte("data"), os.ModePerm)
	assert.NoError(t, err)
	err = os.Chmod(filepath.Dir(testFile), 0001)
	assert.NoError(t, err)
	_, err = connection.uploadFile(fs, testFile, "test", 0)
	assert.Error(t, err)
	err = os.Chmod(filepath.Dir(testFile), os.ModePerm)
	assert.NoError(t, err)
	err = os.RemoveAll(filepath.Dir(testFile))
	assert.NoError(t, err)
}

func TestAVBLErrors(t *testing.T) {
	user := dataprovider.User{
		BaseUser: sdk.BaseUser{
			Username: "user",
			HomeDir:  filepath.Clean(os.TempDir()),
		},
	}
	user.Permissions = make(map[string][]string)
	user.Permissions["/"] = []string{dataprovider.PermAny}
	mockCC := mockFTPClientContext{}
	connID := fmt.Sprintf("%v", mockCC.ID())
	connection := &Connection{
		BaseConnection: common.NewBaseConnection(connID, common.ProtocolFTP, "", "", user),
		clientContext:  mockCC,
	}
	_, err := connection.GetAvailableSpace("/")
	assert.NoError(t, err)
	_, err = connection.GetAvailableSpace("/missing-path")
	assert.Error(t, err)
	assert.True(t, errors.Is(err, fs.ErrNotExist))
}

func TestUploadOverwriteErrors(t *testing.T) {
	user := dataprovider.User{
		BaseUser: sdk.BaseUser{
			Username: "user",
			HomeDir:  filepath.Clean(os.TempDir()),
		},
	}
	user.Permissions = make(map[string][]string)
	user.Permissions["/"] = []string{dataprovider.PermAny}
	mockCC := mockFTPClientContext{}
	connID := fmt.Sprintf("%v", mockCC.ID())
	fs := newMockOsFs(nil, nil, false, connID, user.GetHomeDir())
	connection := &Connection{
		BaseConnection: common.NewBaseConnection(connID, common.ProtocolFTP, "", "", user),
		clientContext:  mockCC,
	}
	flags := 0
	flags |= os.O_APPEND
	_, err := connection.handleFTPUploadToExistingFile(fs, flags, "", "", 0, "")
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrOpUnsupported.Error())
	}

	f, err := os.CreateTemp("", "temp")
	assert.NoError(t, err)
	err = f.Close()
	assert.NoError(t, err)
	flags = 0
	flags |= os.O_CREATE
	flags |= os.O_TRUNC
	tr, err := connection.handleFTPUploadToExistingFile(fs, flags, f.Name(), f.Name(), 123, f.Name())
	if assert.NoError(t, err) {
		transfer := tr.(*transfer)
		transfers := connection.GetTransfers()
		if assert.Equal(t, 1, len(transfers)) {
			assert.Equal(t, transfers[0].ID, transfer.GetID())
			assert.Equal(t, int64(123), transfer.InitialSize)
			err = transfer.Close()
			assert.NoError(t, err)
			assert.Equal(t, 0, len(connection.GetTransfers()))
		}
	}
	err = os.Remove(f.Name())
	assert.NoError(t, err)

	_, err = connection.handleFTPUploadToExistingFile(fs, os.O_TRUNC, filepath.Join(os.TempDir(), "sub", "file"),
		filepath.Join(os.TempDir(), "sub", "file1"), 0, "/sub/file1")
	assert.Error(t, err)
	fs = vfs.NewOsFs(connID, user.GetHomeDir(), "")
	_, err = connection.handleFTPUploadToExistingFile(fs, 0, "missing1", "missing2", 0, "missing")
	assert.Error(t, err)
}

func TestTransferErrors(t *testing.T) {
	testfile := "testfile"
	file, err := os.Create(testfile)
	assert.NoError(t, err)
	user := dataprovider.User{
		BaseUser: sdk.BaseUser{
			Username: "user",
			HomeDir:  filepath.Clean(os.TempDir()),
		},
	}
	user.Permissions = make(map[string][]string)
	user.Permissions["/"] = []string{dataprovider.PermAny}
	mockCC := mockFTPClientContext{}
	connID := fmt.Sprintf("%v", mockCC.ID())
	fs := newMockOsFs(nil, nil, false, connID, user.GetHomeDir())
	connection := &Connection{
		BaseConnection: common.NewBaseConnection(connID, common.ProtocolFTP, "", "", user),
		clientContext:  mockCC,
	}
	baseTransfer := common.NewBaseTransfer(file, connection.BaseConnection, nil, file.Name(), file.Name(), testfile,
		common.TransferDownload, 0, 0, 0, 0, false, fs, dataprovider.TransferQuota{})
	tr := newTransfer(baseTransfer, nil, nil, 0)
	err = tr.Close()
	assert.NoError(t, err)
	_, err = tr.Seek(10, 0)
	assert.Error(t, err)
	buf := make([]byte, 64)
	_, err = tr.Read(buf)
	assert.Error(t, err)
	err = tr.Close()
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrTransferClosed.Error())
	}
	assert.Len(t, connection.GetTransfers(), 0)

	r, _, err := pipeat.Pipe()
	assert.NoError(t, err)
	baseTransfer = common.NewBaseTransfer(nil, connection.BaseConnection, nil, testfile, testfile, testfile,
		common.TransferUpload, 0, 0, 0, 0, false, fs, dataprovider.TransferQuota{})
	tr = newTransfer(baseTransfer, nil, r, 10)
	pos, err := tr.Seek(10, 0)
	assert.NoError(t, err)
	assert.Equal(t, pos, tr.expectedOffset)
	err = tr.closeIO()
	assert.NoError(t, err)

	r, w, err := pipeat.Pipe()
	assert.NoError(t, err)
	pipeWriter := vfs.NewPipeWriter(w)
	baseTransfer = common.NewBaseTransfer(nil, connection.BaseConnection, nil, testfile, testfile, testfile,
		common.TransferUpload, 0, 0, 0, 0, false, fs, dataprovider.TransferQuota{})
	tr = newTransfer(baseTransfer, pipeWriter, nil, 0)

	err = r.Close()
	assert.NoError(t, err)
	errFake := fmt.Errorf("fake upload error")
	go func() {
		time.Sleep(100 * time.Millisecond)
		pipeWriter.Done(errFake)
	}()
	err = tr.closeIO()
	assert.EqualError(t, err, errFake.Error())
	_, err = tr.Seek(1, 0)
	if assert.Error(t, err) {
		assert.EqualError(t, err, common.ErrOpUnsupported.Error())
	}
	err = os.Remove(testfile)
	assert.NoError(t, err)
}

func TestVerifyTLSConnection(t *testing.T) {
	oldCertMgr := certMgr

	caCrlPath := filepath.Join(os.TempDir(), "testcrl.crt")
	certPath := filepath.Join(os.TempDir(), "test.crt")
	keyPath := filepath.Join(os.TempDir(), "test.key")
	err := os.WriteFile(caCrlPath, []byte(caCRL), os.ModePerm)
	assert.NoError(t, err)
	err = os.WriteFile(certPath, []byte(ftpsCert), os.ModePerm)
	assert.NoError(t, err)
	err = os.WriteFile(keyPath, []byte(ftpsKey), os.ModePerm)
	assert.NoError(t, err)
	keyPairs := []common.TLSKeyPair{
		{
			Cert: certPath,
			Key:  keyPath,
			ID:   common.DefaultTLSKeyPaidID,
		},
	}
	certMgr, err = common.NewCertManager(keyPairs, "", "ftp_test")
	assert.NoError(t, err)

	certMgr.SetCARevocationLists([]string{caCrlPath})
	err = certMgr.LoadCRLs()
	assert.NoError(t, err)

	crt, err := tls.X509KeyPair([]byte(client1Crt), []byte(client1Key))
	assert.NoError(t, err)
	x509crt, err := x509.ParseCertificate(crt.Certificate[0])
	assert.NoError(t, err)

	server := Server{}
	state := tls.ConnectionState{
		PeerCertificates: []*x509.Certificate{x509crt},
	}

	err = server.verifyTLSConnection(state)
	assert.Error(t, err) // no verified certification chain

	crt, err = tls.X509KeyPair([]byte(caCRT), []byte(caKey))
	assert.NoError(t, err)

	x509CAcrt, err := x509.ParseCertificate(crt.Certificate[0])
	assert.NoError(t, err)

	state.VerifiedChains = append(state.VerifiedChains, []*x509.Certificate{x509crt, x509CAcrt})
	err = server.verifyTLSConnection(state)
	assert.NoError(t, err)

	crt, err = tls.X509KeyPair([]byte(client2Crt), []byte(client2Key))
	assert.NoError(t, err)
	x509crtRevoked, err := x509.ParseCertificate(crt.Certificate[0])
	assert.NoError(t, err)

	state.VerifiedChains = append(state.VerifiedChains, []*x509.Certificate{x509crtRevoked, x509CAcrt})
	state.PeerCertificates = []*x509.Certificate{x509crtRevoked}
	err = server.verifyTLSConnection(state)
	assert.EqualError(t, err, common.ErrCrtRevoked.Error())

	err = os.Remove(caCrlPath)
	assert.NoError(t, err)
	err = os.Remove(certPath)
	assert.NoError(t, err)
	err = os.Remove(keyPath)
	assert.NoError(t, err)

	certMgr = oldCertMgr
}

func TestCiphers(t *testing.T) {
	b := Binding{
		TLSCipherSuites: []string{},
	}
	b.setCiphers()
	require.Nil(t, b.ciphers)
	b.TLSCipherSuites = []string{"TLS_AES_128_GCM_SHA256", "TLS_AES_256_GCM_SHA384"}
	b.setCiphers()
	require.Len(t, b.ciphers, 2)
	require.Equal(t, []uint16{tls.TLS_AES_128_GCM_SHA256, tls.TLS_AES_256_GCM_SHA384}, b.ciphers)
}

func TestPassiveIPResolver(t *testing.T) {
	b := Binding{
		PassiveIPOverrides: []PassiveIPOverride{
			{},
		},
	}
	err := b.checkPassiveIP()
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "passive IP networks override cannot be empty")
	b = Binding{
		PassiveIPOverrides: []PassiveIPOverride{
			{
				IP: "invalid ip",
			},
		},
	}
	err = b.checkPassiveIP()
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "is not valid")

	b = Binding{
		PassiveIPOverrides: []PassiveIPOverride{
			{
				IP:       "192.168.1.1",
				Networks: []string{"192.168.1.0/24", "invalid cidr"},
			},
		},
	}
	err = b.checkPassiveIP()
	assert.Error(t, err)
	assert.Contains(t, err.Error(), "invalid passive IP networks override")
	b = Binding{
		ForcePassiveIP: "192.168.2.1",
		PassiveIPOverrides: []PassiveIPOverride{
			{
				IP:       "::ffff:192.168.1.1",
				Networks: []string{"192.168.1.0/24"},
			},
		},
	}
	err = b.checkPassiveIP()
	assert.NoError(t, err)
	assert.NotEmpty(t, b.PassiveIPOverrides[0].GetNetworksAsString())
	assert.Equal(t, "192.168.1.1", b.PassiveIPOverrides[0].IP)
	require.Len(t, b.PassiveIPOverrides[0].parsedNetworks, 1)
	ip := net.ParseIP("192.168.1.2")
	assert.True(t, b.PassiveIPOverrides[0].parsedNetworks[0](ip))
	ip = net.ParseIP("192.168.0.2")
	assert.False(t, b.PassiveIPOverrides[0].parsedNetworks[0](ip))

	mockCC := mockFTPClientContext{
		remoteIP: "192.168.1.10",
		localIP:  "192.168.1.3",
	}
	passiveIP, err := b.passiveIPResolver(mockCC)
	assert.NoError(t, err)
	assert.Equal(t, "192.168.1.1", passiveIP)
	b.PassiveIPOverrides[0].IP = ""
	passiveIP, err = b.passiveIPResolver(mockCC)
	assert.NoError(t, err)
	assert.Equal(t, "192.168.1.3", passiveIP)
	mockCC.remoteIP = "172.16.2.3"
	passiveIP, err = b.passiveIPResolver(mockCC)
	assert.NoError(t, err)
	assert.Equal(t, b.ForcePassiveIP, passiveIP)
}

func TestRelativePath(t *testing.T) {
	rel := getPathRelativeTo("/testpath", "/testpath")
	assert.Empty(t, rel)
	rel = getPathRelativeTo("/", "/")
	assert.Empty(t, rel)
	rel = getPathRelativeTo("/", "/dir/sub")
	assert.Equal(t, "dir/sub", rel)
	rel = getPathRelativeTo("./", "/dir/sub")
	assert.Equal(t, "/dir/sub", rel)
	rel = getPathRelativeTo("/sub", "/dir/sub")
	assert.Equal(t, "../dir/sub", rel)
	rel = getPathRelativeTo("/dir", "/dir/sub")
	assert.Equal(t, "sub", rel)
	rel = getPathRelativeTo("/dir/sub", "/dir")
	assert.Equal(t, "../", rel)
	rel = getPathRelativeTo("dir", "/dir1")
	assert.Equal(t, "/dir1", rel)
	rel = getPathRelativeTo("", "/dir2")
	assert.Equal(t, "dir2", rel)
	rel = getPathRelativeTo(".", "/dir2")
	assert.Equal(t, "/dir2", rel)
	rel = getPathRelativeTo("/dir3", "dir3")
	assert.Equal(t, "dir3", rel)
}
