Documentation ¶
Overview ¶
Package sftp implements the SSH File Transfer Protocol as described in https://tools.ietf.org/html/draft-ietf-secsh-filexfer-02
Example ¶
package main import ( "log" "github.com/pkg/sftp" "golang.org/x/crypto/ssh" ) func main() { var conn *ssh.Client // open an SFTP session over an existing ssh connection. sftp, err := sftp.NewClient(conn) if err != nil { log.Fatal(err) } defer sftp.Close() // walk a directory w := sftp.Walk("/home/user") for w.Step() { if w.Err() != nil { continue } log.Println(w.Path()) } // leave your mark f, err := sftp.Create("hello.txt") if err != nil { log.Fatal(err) } if _, err := f.Write([]byte("Hello world!")); err != nil { log.Fatal(err) } // check it's there fi, err := sftp.Lstat("hello.txt") if err != nil { log.Fatal(err) } log.Println(fi) }
Output:
Index ¶
- Constants
- Variables
- func Join(elem ...string) string
- func Match(pattern, name string) (matched bool, err error)
- func Split(path string) (dir, file string)
- type Client
- func (c *Client) Chmod(path string, mode os.FileMode) error
- func (c *Client) Chown(path string, uid, gid int) error
- func (c *Client) Chtimes(path string, atime time.Time, mtime time.Time) error
- func (c *Client) Close() error
- func (c *Client) Create(path string) (*File, error)
- func (c *Client) Getwd() (string, error)
- func (c *Client) Glob(pattern string) (matches []string, err error)
- func (c *Client) Join(elem ...string) string
- func (c *Client) Lstat(p string) (os.FileInfo, error)
- func (c *Client) Mkdir(path string) error
- func (c *Client) MkdirAll(path string) error
- func (c *Client) Open(path string) (*File, error)
- func (c *Client) OpenFile(path string, f int) (*File, error)
- func (c *Client) PosixRename(oldname, newname string) error
- func (c *Client) ReadDir(p string) ([]os.FileInfo, error)
- func (c *Client) ReadLink(p string) (string, error)
- func (c *Client) Remove(path string) error
- func (c *Client) RemoveDirectory(path string) error
- func (c *Client) Rename(oldname, newname string) error
- func (c *Client) Stat(p string) (os.FileInfo, error)
- func (c *Client) StatVFS(path string) (*StatVFS, error)
- func (c *Client) Symlink(oldname, newname string) error
- func (c *Client) Truncate(path string, size int64) error
- func (c *Client) Walk(root string) *fs.Walker
- type ClientOption
- type File
- func (f *File) Chmod(mode os.FileMode) error
- func (f *File) Chown(uid, gid int) error
- func (f *File) Close() error
- func (f *File) Name() string
- func (f *File) Read(b []byte) (int, error)
- func (f *File) ReadFrom(r io.Reader) (int64, error)
- func (f *File) Seek(offset int64, whence int) (int64, error)
- func (f *File) Stat() (os.FileInfo, error)
- func (f *File) Truncate(size int64) error
- func (f *File) Write(b []byte) (int, error)
- func (f *File) WriteTo(w io.Writer) (int64, error)
- type FileAttrFlags
- type FileCmder
- type FileLister
- type FileOpenFlags
- type FileReader
- type FileStat
- type FileWriter
- type Handlers
- type ListerAt
- type Request
- type RequestServer
- type Server
- type ServerOption
- type StatExtended
- type StatVFS
- type StatusError
Examples ¶
Constants ¶
const ( ErrSshFxOk = fxerr(ssh_FX_OK) ErrSshFxEof = fxerr(ssh_FX_EOF) ErrSshFxNoSuchFile = fxerr(ssh_FX_NO_SUCH_FILE) ErrSshFxPermissionDenied = fxerr(ssh_FX_PERMISSION_DENIED) ErrSshFxFailure = fxerr(ssh_FX_FAILURE) ErrSshFxBadMessage = fxerr(ssh_FX_BAD_MESSAGE) ErrSshFxNoConnection = fxerr(ssh_FX_NO_CONNECTION) ErrSshFxConnectionLost = fxerr(ssh_FX_CONNECTION_LOST) ErrSshFxOpUnsupported = fxerr(ssh_FX_OP_UNSUPPORTED) )
const (
SftpServerWorkerCount = 8
)
Variables ¶
var ErrBadPattern = path.ErrBadPattern
ErrBadPattern indicates a globbing pattern was malformed.
var InternalInconsistency = errors.New("internal inconsistency")
InternalInconsistency indicates the packets sent and the data queued to be written to the file don't match up. It is an unusual error and usually is caused by bad behavior server side or connection issues. The error is limited in scope to the call where it happened, the client object is still OK to use as long as the connection is still open.
var MaxFilelist int64 = 100
MaxFilelist is the max number of files to return in a readdir batch.
Functions ¶
func Join ¶
Join joins any number of path elements into a single path, adding a Separator if necessary. all empty strings are ignored.
func Match ¶
Match reports whether name matches the shell file name pattern. The pattern syntax is:
pattern: { term } term: '*' matches any sequence of non-Separator characters '?' matches any single non-Separator character '[' [ '^' ] { character-range } ']' character class (must be non-empty) c matches character c (c != '*', '?', '\\', '[') '\\' c matches character c character-range: c matches character c (c != '\\', '-', ']') '\\' c matches character c lo '-' hi matches character c for lo <= c <= hi
Match requires pattern to match all of name, not just a substring. The only possible returned error is ErrBadPattern, when pattern is malformed.
Types ¶
type Client ¶
type Client struct {
// contains filtered or unexported fields
}
Client represents an SFTP session on a *ssh.ClientConn SSH connection. Multiple Clients can be active on a single SSH connection, and a Client may be called concurrently from multiple Goroutines.
Client implements the github.com/kr/fs.FileSystem interface.
func NewClient ¶
func NewClient(conn *ssh.Client, opts ...ClientOption) (*Client, error)
NewClient creates a new SFTP client on conn, using zero or more option functions.
func NewClientPipe ¶
func NewClientPipe(rd io.Reader, wr io.WriteCloser, opts ...ClientOption) (*Client, error)
NewClientPipe creates a new SFTP client given a Reader and a WriteCloser. This can be used for connecting to an SFTP server over TCP/TLS or by using the system's ssh client program (e.g. via exec.Command).
Example ¶
package main import ( "fmt" "log" "os" "os/exec" "github.com/pkg/sftp" ) func main() { // Connect to a remote host and request the sftp subsystem via the 'ssh' // command. This assumes that passwordless login is correctly configured. cmd := exec.Command("ssh", "example.com", "-s", "sftp") // send errors from ssh to stderr cmd.Stderr = os.Stderr // get stdin and stdout wr, err := cmd.StdinPipe() if err != nil { log.Fatal(err) } rd, err := cmd.StdoutPipe() if err != nil { log.Fatal(err) } // start the process if err := cmd.Start(); err != nil { log.Fatal(err) } defer cmd.Wait() // open the SFTP session client, err := sftp.NewClientPipe(rd, wr) if err != nil { log.Fatal(err) } // read a directory list, err := client.ReadDir("/") if err != nil { log.Fatal(err) } // print contents for _, item := range list { fmt.Println(item.Name()) } // close the connection client.Close() }
Output:
func (*Client) Create ¶
Create creates the named file mode 0666 (before umask), truncating it if it already exists. If successful, methods on the returned File can be used for I/O; the associated file descriptor has mode O_RDWR. If you need more control over the flags/mode used to open the file see client.OpenFile.
func (*Client) Getwd ¶
Getwd returns the current working directory of the server. Operations involving relative paths will be based at this location.
func (*Client) Glob ¶
Glob returns the names of all files matching pattern or nil if there is no matching file. The syntax of patterns is the same as in Match. The pattern may describe hierarchical names such as /usr/*/bin/ed (assuming the Separator is '/').
Glob ignores file system errors such as I/O errors reading directories. The only possible returned error is ErrBadPattern, when pattern is malformed.
func (*Client) Join ¶
Join joins any number of path elements into a single path, adding a separating slash if necessary. The result is Cleaned; in particular, all empty strings are ignored.
func (*Client) Lstat ¶
Lstat returns a FileInfo structure describing the file specified by path 'p'. If 'p' is a symbolic link, the returned FileInfo structure describes the symbolic link.
func (*Client) Mkdir ¶
Mkdir creates the specified directory. An error will be returned if a file or directory with the specified path already exists, or if the directory's parent folder does not exist (the method cannot create complete paths).
Example (Parents) ¶
package main import ( "fmt" "log" "os" "path" "strings" "github.com/pkg/sftp" "golang.org/x/crypto/ssh" ) func main() { // Example of mimicing 'mkdir --parents'; I.E. recursively create // directoryies and don't error if any directories already exists. var conn *ssh.Client client, err := sftp.NewClient(conn) if err != nil { log.Fatal(err) } defer client.Close() sshFxFailure := uint32(4) mkdirParents := func(client *sftp.Client, dir string) (err error) { var parents string if path.IsAbs(dir) { // Otherwise, an absolute path given below would be turned in to a relative one // by splitting on "/" parents = "/" } for _, name := range strings.Split(dir, "/") { if name == "" { // Paths with double-/ in them should just move along // this will also catch the case of the first character being a "/", i.e. an absolute path continue } parents = path.Join(parents, name) err = client.Mkdir(parents) if status, ok := err.(*sftp.StatusError); ok { if status.Code == sshFxFailure { var fi os.FileInfo fi, err = client.Stat(parents) if err == nil { if !fi.IsDir() { return fmt.Errorf("File exists: %s", parents) } } } } if err != nil { break } } return err } err = mkdirParents(client, "/tmp/foo/bar") if err != nil { log.Fatal(err) } }
Output:
func (*Client) MkdirAll ¶
MkdirAll creates a directory named path, along with any necessary parents, and returns nil, or else returns an error. If path is already a directory, MkdirAll does nothing and returns nil. If path contains a regular file, an error is returned
func (*Client) Open ¶
Open opens the named file for reading. If successful, methods on the returned file can be used for reading; the associated file descriptor has mode O_RDONLY.
func (*Client) OpenFile ¶
OpenFile is the generalized open call; most users will use Open or Create instead. It opens the named file with specified flag (O_RDONLY etc.). If successful, methods on the returned File can be used for I/O.
func (*Client) PosixRename ¶
PosixRename renames a file using the posix-rename@openssh.com extension which will replace newname if it already exists.
func (*Client) ReadDir ¶
ReadDir reads the directory named by dirname and returns a list of directory entries.
func (*Client) Remove ¶
Remove removes the specified file or directory. An error will be returned if no file or directory with the specified path exists, or if the specified directory is not empty.
func (*Client) RemoveDirectory ¶
RemoveDirectory removes a directory path.
func (*Client) Stat ¶
Stat returns a FileInfo structure describing the file specified by path 'p'. If 'p' is a symbolic link, the returned FileInfo structure describes the referent file.
func (*Client) StatVFS ¶
StatVFS retrieves VFS statistics from a remote host.
It implements the statvfs@openssh.com SSH_FXP_EXTENDED feature from http://www.opensource.apple.com/source/OpenSSH/OpenSSH-175/openssh/PROTOCOL?txt.
type ClientOption ¶
A ClientOption is a function which applies configuration to a Client.
func MaxConcurrentRequestsPerFile ¶
func MaxConcurrentRequestsPerFile(n int) ClientOption
MaxConcurrentRequestsPerFile sets the maximum concurrent requests allowed for a single file.
The default maximum concurrent requests is 64.
func MaxPacket ¶
func MaxPacket(size int) ClientOption
MaxPacket sets the maximum size of the payload, measured in bytes. This option only accepts sizes servers should support, ie. <= 32768 bytes. This is a synonym for MaxPacketChecked that provides backward compatibility.
If you get the error "failed to send packet header: EOF" when copying a large file, try lowering this number.
The default packet size is 32768 bytes.
func MaxPacketChecked ¶
func MaxPacketChecked(size int) ClientOption
MaxPacketChecked sets the maximum size of the payload, measured in bytes. This option only accepts sizes servers should support, ie. <= 32768 bytes.
If you get the error "failed to send packet header: EOF" when copying a large file, try lowering this number.
The default packet size is 32768 bytes.
func MaxPacketUnchecked ¶
func MaxPacketUnchecked(size int) ClientOption
MaxPacketUnchecked sets the maximum size of the payload, measured in bytes. It accepts sizes larger than the 32768 bytes all servers should support. Only use a setting higher than 32768 if your application always connects to the same server or after sufficiently broad testing.
If you get the error "failed to send packet header: EOF" when copying a large file, try lowering this number.
The default packet size is 32768 bytes.
type File ¶
type File struct {
// contains filtered or unexported fields
}
File represents a remote file.
func (*File) Close ¶
Close closes the File, rendering it unusable for I/O. It returns an error, if any.
func (*File) Read ¶
Read reads up to len(b) bytes from the File. It returns the number of bytes read and an error, if any. Read follows io.Reader semantics, so when Read encounters an error or EOF condition after successfully reading n > 0 bytes, it returns the number of bytes read.
To maximise throughput for transferring the entire file (especially over high latency links) it is recommended to use WriteTo rather than calling Read multiple times. io.Copy will do this automatically.
func (*File) ReadFrom ¶
ReadFrom reads data from r until EOF and writes it to the file. The return value is the number of bytes read. Any error except io.EOF encountered during the read is also returned.
This method is preferred over calling Write multiple times to maximise throughput for transferring the entire file (especially over high latency links).
Example (Bufio) ¶
package main import ( "bufio" "io" "github.com/pkg/sftp" ) func main() { // Using Bufio to buffer writes going to an sftp.File won't buffer as it // skips buffering if the underlying writer support ReadFrom. The // workaround is to wrap your writer in a struct that only implements // io.Writer. // // For background see github.com/pkg/sftp/issues/125 var data_source io.Reader var f *sftp.File type writerOnly struct{ io.Writer } bw := bufio.NewWriter(writerOnly{f}) // no ReadFrom() bw.ReadFrom(data_source) }
Output:
func (*File) Seek ¶
Seek implements io.Seeker by setting the client offset for the next Read or Write. It returns the next offset read. Seeking before or after the end of the file is undefined. Seeking relative to the end calls Stat.
func (*File) Truncate ¶
Truncate sets the size of the current file. Although it may be safely assumed that if the size is less than its current size it will be truncated to fit, the SFTP protocol does not specify what behavior the server should do when setting size greater than the current size.
func (*File) Write ¶
Write writes len(b) bytes to the File. It returns the number of bytes written and an error, if any. Write returns a non-nil error when n != len(b).
To maximise throughput for transferring the entire file (especially over high latency links) it is recommended to use ReadFrom rather than calling Write multiple times. io.Copy will do this automatically.
func (*File) WriteTo ¶
WriteTo writes the file to w. The return value is the number of bytes written. Any error encountered during the write is also returned.
This method is preferred over calling Read multiple times to maximise throughput for transferring the entire file (especially over high latency links).
type FileAttrFlags ¶
type FileAttrFlags struct {
Size, UidGid, Permissions, Acmodtime bool
}
Flags that indicate whether SFTP file attributes were passed. When a flag is true the corresponding attribute should be available from the FileStat object returned by Attributes method. Used with SetStat.
type FileCmder ¶
FileCmder should return an error Note in cases of an error, the error text will be sent to the client. Called for Methods: Setstat, Rename, Rmdir, Mkdir, Symlink, Remove
type FileLister ¶
FileLister should return an object that fulfils the ListerAt interface Note in cases of an error, the error text will be sent to the client. Called for Methods: List, Stat, Readlink
type FileOpenFlags ¶
type FileOpenFlags struct {
Read, Write, Append, Creat, Trunc, Excl bool
}
File Open and Write Flags. Correlate directly with with os.OpenFile flags (https://golang.org/pkg/os/#pkg-constants).
type FileReader ¶
FileReader should return an io.ReaderAt for the filepath Note in cases of an error, the error text will be sent to the client. Called for Methods: Get
type FileStat ¶
type FileStat struct { Size uint64 Mode uint32 Mtime uint32 Atime uint32 UID uint32 GID uint32 Extended []StatExtended }
FileStat holds the original unmarshalled values from a call to READDIR or *STAT. It is exported for the purposes of accessing the raw values via os.FileInfo.Sys(). It is also used server side to store the unmarshalled values for SetStat.
type FileWriter ¶
FileWriter should return an io.WriterAt for the filepath.
The request server code will call Close() on the returned io.WriterAt ojbect if an io.Closer type assertion succeeds. Note in cases of an error, the error text will be sent to the client. Called for Methods: Put, Open
type Handlers ¶
type Handlers struct { FileGet FileReader FilePut FileWriter FileCmd FileCmder FileList FileLister }
Handlers contains the 4 SFTP server request handlers.
func InMemHandler ¶
func InMemHandler() Handlers
InMemHandler returns a Hanlders object with the test handlers.
type ListerAt ¶
ListerAt does for file lists what io.ReaderAt does for files. ListAt should return the number of entries copied and an io.EOF error if at end of list. This is testable by comparing how many you copied to how many could be copied (eg. n < len(ls) below). The copy() builtin is best for the copying. Note in cases of an error, the error text will be sent to the client.
type Request ¶
type Request struct { // Get, Put, Setstat, Stat, Rename, Remove // Rmdir, Mkdir, List, Readlink, Symlink Method string Filepath string Flags uint32 Attrs []byte // convert to sub-struct Target string // for renames and sym-links // contains filtered or unexported fields }
Request contains the data and state for the incoming service request.
func NewRequest ¶
NewRequest creates a new Request object.
func (*Request) AttrFlags ¶
func (r *Request) AttrFlags() FileAttrFlags
FileAttrFlags returns a FileAttrFlags boolean struct based on the bitmap/uint32 file attribute flags from the SFTP packaet.
func (*Request) Attributes ¶
Attributres parses file attributes byte blob and return them in a FileStat object.
func (*Request) Context ¶
Context returns the request's context. To change the context, use WithContext.
The returned context is always non-nil; it defaults to the background context.
For incoming server requests, the context is canceled when the request is complete or the client's connection closes.
func (*Request) Pflags ¶
func (r *Request) Pflags() FileOpenFlags
Pflags converts the bitmap/uint32 from SFTP Open packet pflag values, into a FileOpenFlags struct with booleans set for flags set in bitmap.
type RequestServer ¶
type RequestServer struct { Handlers Handlers // contains filtered or unexported fields }
RequestServer abstracts the sftp protocol with an http request-like protocol
func NewRequestServer ¶
func NewRequestServer(rwc io.ReadWriteCloser, h Handlers) *RequestServer
NewRequestServer creates/allocates/returns new RequestServer. Normally there there will be one server per user-session.
func (*RequestServer) Close ¶
func (rs *RequestServer) Close() error
Close the read/write/closer to trigger exiting the main server loop
func (*RequestServer) Serve ¶
func (rs *RequestServer) Serve() error
Serve requests for user session
type Server ¶
type Server struct {
// contains filtered or unexported fields
}
Server is an SSH File Transfer Protocol (sftp) server. This is intended to provide the sftp subsystem to an ssh server daemon. This implementation currently supports most of sftp server protocol version 3, as specified at http://tools.ietf.org/html/draft-ietf-secsh-filexfer-02
func NewServer ¶
func NewServer(rwc io.ReadWriteCloser, options ...ServerOption) (*Server, error)
NewServer creates a new Server instance around the provided streams, serving content from the root of the filesystem. Optionally, ServerOption functions may be specified to further configure the Server.
A subsequent call to Serve() is required to begin serving files over SFTP.
type ServerOption ¶
A ServerOption is a function which applies configuration to a Server.
func ReadOnly ¶
func ReadOnly() ServerOption
ReadOnly configures a Server to serve files in read-only mode.
func WithDebug ¶
func WithDebug(w io.Writer) ServerOption
WithDebug enables Server debugging output to the supplied io.Writer.
type StatExtended ¶
StatExtended contains additional, extended information for a FileStat.
type StatVFS ¶
type StatVFS struct { ID uint32 Bsize uint64 /* file system block size */ Frsize uint64 /* fundamental fs block size */ Blocks uint64 /* number of blocks (unit f_frsize) */ Bfree uint64 /* free blocks in file system */ Bavail uint64 /* free blocks for non-root */ Files uint64 /* total file inodes */ Ffree uint64 /* free file inodes */ Favail uint64 /* free file inodes for to non-root */ Fsid uint64 /* file system id */ Flag uint64 /* bit mask of f_flag values */ Namemax uint64 /* maximum filename length */ }
A StatVFS contains statistics about a filesystem.
func (*StatVFS) MarshalBinary ¶
Convert to ssh_FXP_EXTENDED_REPLY packet binary format
func (*StatVFS) TotalSpace ¶
TotalSpace calculates the amount of total space in a filesystem.
type StatusError ¶
type StatusError struct { Code uint32 // contains filtered or unexported fields }
A StatusError is returned when an SFTP operation fails, and provides additional information about the failure.
func (*StatusError) Error ¶
func (s *StatusError) Error() string
Source Files ¶
- attrs.go
- attrs_unix.go
- client.go
- conn.go
- match.go
- packet-manager.go
- packet-typing.go
- packet.go
- release.go
- request-attrs.go
- request-errors.go
- request-example.go
- request-interfaces.go
- request-server.go
- request-unix.go
- request.go
- server.go
- server_statvfs_impl.go
- server_statvfs_linux.go
- server_unix.go
- sftp.go
Directories ¶
Path | Synopsis |
---|---|
examples
|
|
buffered-read-benchmark
buffered-read-benchmark benchmarks the peformance of reading from /dev/zero on the server to a []byte on the client via io.Copy.
|
buffered-read-benchmark benchmarks the peformance of reading from /dev/zero on the server to a []byte on the client via io.Copy. |
buffered-write-benchmark
buffered-write-benchmark benchmarks the peformance of writing a single large []byte on the client to /dev/null on the server via io.Copy.
|
buffered-write-benchmark benchmarks the peformance of writing a single large []byte on the client to /dev/null on the server via io.Copy. |
request-server
An example SFTP server implementation using the golang SSH package.
|
An example SFTP server implementation using the golang SSH package. |
sftp-server
An example SFTP server implementation using the golang SSH package.
|
An example SFTP server implementation using the golang SSH package. |
streaming-read-benchmark
streaming-read-benchmark benchmarks the peformance of reading from /dev/zero on the server to /dev/null on the client via io.Copy.
|
streaming-read-benchmark benchmarks the peformance of reading from /dev/zero on the server to /dev/null on the client via io.Copy. |
streaming-write-benchmark
streaming-write-benchmark benchmarks the peformance of writing from /dev/zero on the client to /dev/null on the server via io.Copy.
|
streaming-write-benchmark benchmarks the peformance of writing from /dev/zero on the client to /dev/null on the server via io.Copy. |