From 0ee29e31ddcc81f541de7459b0a5e40dfa552672 Mon Sep 17 00:00:00 2001 From: Quentin Dufour Date: Fri, 19 Nov 2021 19:54:49 +0100 Subject: Working on SFTP --- sftp/sftp.go | 258 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 258 insertions(+) create mode 100644 sftp/sftp.go (limited to 'sftp/sftp.go') diff --git a/sftp/sftp.go b/sftp/sftp.go new file mode 100644 index 0000000..9a63c39 --- /dev/null +++ b/sftp/sftp.go @@ -0,0 +1,258 @@ +// 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 +} -- cgit v1.2.3