// Package sftp implements the SSH File Transfer Protocol as described in
// https://tools.ietf.org/html/draft-ietf-secsh-filexfer-02
package sftp
import (
"fmt"
)
const (
sshFxpInit = 1
sshFxpVersion = 2
sshFxpOpen = 3
sshFxpClose = 4
sshFxpRead = 5
sshFxpWrite = 6
sshFxpLstat = 7
sshFxpFstat = 8
sshFxpSetstat = 9
sshFxpFsetstat = 10
sshFxpOpendir = 11
sshFxpReaddir = 12
sshFxpRemove = 13
sshFxpMkdir = 14
sshFxpRmdir = 15
sshFxpRealpath = 16
sshFxpStat = 17
sshFxpRename = 18
sshFxpReadlink = 19
sshFxpSymlink = 20
sshFxpStatus = 101
sshFxpHandle = 102
sshFxpData = 103
sshFxpName = 104
sshFxpAttrs = 105
sshFxpExtended = 200
sshFxpExtendedReply = 201
)
const (
sshFxOk = 0
sshFxEOF = 1
sshFxNoSuchFile = 2
sshFxPermissionDenied = 3
sshFxFailure = 4
sshFxBadMessage = 5
sshFxNoConnection = 6
sshFxConnectionLost = 7
sshFxOPUnsupported = 8
// see draft-ietf-secsh-filexfer-13
// https://tools.ietf.org/html/draft-ietf-secsh-filexfer-13#section-9.1
sshFxInvalidHandle = 9
sshFxNoSuchPath = 10
sshFxFileAlreadyExists = 11
sshFxWriteProtect = 12
sshFxNoMedia = 13
sshFxNoSpaceOnFilesystem = 14
sshFxQuotaExceeded = 15
sshFxUnknownPrincipal = 16
sshFxLockConflict = 17
sshFxDirNotEmpty = 18
sshFxNotADirectory = 19
sshFxInvalidFilename = 20
sshFxLinkLoop = 21
sshFxCannotDelete = 22
sshFxInvalidParameter = 23
sshFxFileIsADirectory = 24
sshFxByteRangeLockConflict = 25
sshFxByteRangeLockRefused = 26
sshFxDeletePending = 27
sshFxFileCorrupt = 28
sshFxOwnerInvalid = 29
sshFxGroupInvalid = 30
sshFxNoMatchingByteRangeLock = 31
)
const (
sshFxfRead = 0x00000001
sshFxfWrite = 0x00000002
sshFxfAppend = 0x00000004
sshFxfCreat = 0x00000008
sshFxfTrunc = 0x00000010
sshFxfExcl = 0x00000020
)
var (
// supportedSFTPExtensions defines the supported extensions
supportedSFTPExtensions = []sshExtensionPair{
{"hardlink@openssh.com", "1"},
{"posix-rename@openssh.com", "1"},
{"statvfs@openssh.com", "2"},
}
sftpExtensions = supportedSFTPExtensions
)
type fxp uint8
func (f fxp) String() string {
switch f {
case sshFxpInit:
return "SSH_FXP_INIT"
case sshFxpVersion:
return "SSH_FXP_VERSION"
case sshFxpOpen:
return "SSH_FXP_OPEN"
case sshFxpClose:
return "SSH_FXP_CLOSE"
case sshFxpRead:
return "SSH_FXP_READ"
case sshFxpWrite:
return "SSH_FXP_WRITE"
case sshFxpLstat:
return "SSH_FXP_LSTAT"
case sshFxpFstat:
return "SSH_FXP_FSTAT"
case sshFxpSetstat:
return "SSH_FXP_SETSTAT"
case sshFxpFsetstat:
return "SSH_FXP_FSETSTAT"
case sshFxpOpendir:
return "SSH_FXP_OPENDIR"
case sshFxpReaddir:
return "SSH_FXP_READDIR"
case sshFxpRemove:
return "SSH_FXP_REMOVE"
case sshFxpMkdir:
return "SSH_FXP_MKDIR"
case sshFxpRmdir:
return "SSH_FXP_RMDIR"
case sshFxpRealpath:
return "SSH_FXP_REALPATH"
case sshFxpStat:
return "SSH_FXP_STAT"
case sshFxpRename:
return "SSH_FXP_RENAME"
case sshFxpReadlink:
return "SSH_FXP_READLINK"
case sshFxpSymlink:
return "SSH_FXP_SYMLINK"
case sshFxpStatus:
return "SSH_FXP_STATUS"
case sshFxpHandle:
return "SSH_FXP_HANDLE"
case sshFxpData:
return "SSH_FXP_DATA"
case sshFxpName:
return "SSH_FXP_NAME"
case sshFxpAttrs:
return "SSH_FXP_ATTRS"
case sshFxpExtended:
return "SSH_FXP_EXTENDED"
case sshFxpExtendedReply:
return "SSH_FXP_EXTENDED_REPLY"
default:
return "unknown"
}
}
type fx uint8
func (f fx) String() string {
switch f {
case sshFxOk:
return "SSH_FX_OK"
case sshFxEOF:
return "SSH_FX_EOF"
case sshFxNoSuchFile:
return "SSH_FX_NO_SUCH_FILE"
case sshFxPermissionDenied:
return "SSH_FX_PERMISSION_DENIED"
case sshFxFailure:
return "SSH_FX_FAILURE"
case sshFxBadMessage:
return "SSH_FX_BAD_MESSAGE"
case sshFxNoConnection:
return "SSH_FX_NO_CONNECTION"
case sshFxConnectionLost:
return "SSH_FX_CONNECTION_LOST"
case sshFxOPUnsupported:
return "SSH_FX_OP_UNSUPPORTED"
default:
return "unknown"
}
}
type unexpectedPacketErr struct {
want, got uint8
}
func (u *unexpectedPacketErr) Error() string {
return fmt.Sprintf("sftp: unexpected packet: want %v, got %v", fxp(u.want), fxp(u.got))
}
func unimplementedPacketErr(u uint8) error {
return fmt.Errorf("sftp: unimplemented packet type: got %v", fxp(u))
}
type unexpectedIDErr struct{ want, got uint32 }
func (u *unexpectedIDErr) Error() string {
return fmt.Sprintf("sftp: unexpected id: want %d, got %d", u.want, u.got)
}
func unimplementedSeekWhence(whence int) error {
return fmt.Errorf("sftp: unimplemented seek whence %d", whence)
}
func unexpectedCount(want, got uint32) error {
return fmt.Errorf("sftp: unexpected count: want %d, got %d", want, got)
}
type unexpectedVersionErr struct{ want, got uint32 }
func (u *unexpectedVersionErr) Error() string {
return fmt.Sprintf("sftp: unexpected server version: want %v, got %v", u.want, u.got)
}
// A StatusError is returned when an SFTP operation fails, and provides
// additional information about the failure.
type StatusError struct {
Code uint32
msg, lang string
}
func (s *StatusError) Error() string {
return fmt.Sprintf("sftp: %q (%v)", s.msg, fx(s.Code))
}
// FxCode returns the error code typed to match against the exported codes
func (s *StatusError) FxCode() fxerr {
return fxerr(s.Code)
}
func getSupportedExtensionByName(extensionName string) (sshExtensionPair, error) {
for _, supportedExtension := range supportedSFTPExtensions {
if supportedExtension.Name == extensionName {
return supportedExtension, nil
}
}
return sshExtensionPair{}, fmt.Errorf("unsupported extension: %s", extensionName)
}
// SetSFTPExtensions allows to customize the supported server extensions.
// See the variable supportedSFTPExtensions for supported extensions.
// This method accepts a slice of sshExtensionPair names for example 'hardlink@openssh.com'.
// If an invalid extension is given an error will be returned and nothing will be changed
func SetSFTPExtensions(extensions ...string) error {
tempExtensions := []sshExtensionPair{}
for _, extension := range extensions {
sftpExtension, err := getSupportedExtensionByName(extension)
if err != nil {
return err
}
tempExtensions = append(tempExtensions, sftpExtension)
}
sftpExtensions = tempExtensions
return nil
}
