1package openssh
2
3import (
4	sshfx "github.com/pkg/sftp/internal/encoding/ssh/filexfer"
5)
6
7const extensionPosixRename = "posix-rename@openssh.com"
8
9// RegisterExtensionPosixRename registers the "posix-rename@openssh.com" extended packet with the encoding/ssh/filexfer package.
10func RegisterExtensionPosixRename() {
11	sshfx.RegisterExtendedPacketType(extensionPosixRename, func() sshfx.ExtendedData {
12		return new(PosixRenameExtendedPacket)
13	})
14}
15
16// ExtensionPosixRename returns an ExtensionPair suitable to append into an sshfx.InitPacket or sshfx.VersionPacket.
17func ExtensionPosixRename() *sshfx.ExtensionPair {
18	return &sshfx.ExtensionPair{
19		Name: extensionPosixRename,
20		Data: "1",
21	}
22}
23
24// PosixRenameExtendedPacket defines the posix-rename@openssh.com extend packet.
25type PosixRenameExtendedPacket struct {
26	OldPath string
27	NewPath string
28}
29
30// Type returns the SSH_FXP_EXTENDED packet type.
31func (ep *PosixRenameExtendedPacket) Type() sshfx.PacketType {
32	return sshfx.PacketTypeExtended
33}
34
35// MarshalPacket returns ep as a two-part binary encoding of the full extended packet.
36func (ep *PosixRenameExtendedPacket) MarshalPacket(reqid uint32, b []byte) (header, payload []byte, err error) {
37	p := &sshfx.ExtendedPacket{
38		ExtendedRequest: extensionPosixRename,
39
40		Data: ep,
41	}
42	return p.MarshalPacket(reqid, b)
43}
44
45// MarshalInto encodes ep into the binary encoding of the hardlink@openssh.com extended packet-specific data.
46func (ep *PosixRenameExtendedPacket) MarshalInto(buf *sshfx.Buffer) {
47	buf.AppendString(ep.OldPath)
48	buf.AppendString(ep.NewPath)
49}
50
51// MarshalBinary encodes ep into the binary encoding of the hardlink@openssh.com extended packet-specific data.
52//
53// NOTE: This _only_ encodes the packet-specific data, it does not encode the full extended packet.
54func (ep *PosixRenameExtendedPacket) MarshalBinary() ([]byte, error) {
55	// string(oldpath) + string(newpath)
56	size := 4 + len(ep.OldPath) + 4 + len(ep.NewPath)
57
58	buf := sshfx.NewBuffer(make([]byte, 0, size))
59	ep.MarshalInto(buf)
60	return buf.Bytes(), nil
61}
62
63// UnmarshalFrom decodes the hardlink@openssh.com extended packet-specific data from buf.
64func (ep *PosixRenameExtendedPacket) UnmarshalFrom(buf *sshfx.Buffer) (err error) {
65	if ep.OldPath, err = buf.ConsumeString(); err != nil {
66		return err
67	}
68
69	if ep.NewPath, err = buf.ConsumeString(); err != nil {
70		return err
71	}
72
73	return nil
74}
75
76// UnmarshalBinary decodes the hardlink@openssh.com extended packet-specific data into ep.
77func (ep *PosixRenameExtendedPacket) UnmarshalBinary(data []byte) (err error) {
78	return ep.UnmarshalFrom(sshfx.NewBuffer(data))
79}
80