Working on SFTP

1 files changed, 99 insertions, 0 deletions

diff --git a/internal/encoding/ssh/filexfer/init_packets.go b/internal/encoding/ssh/filexfer/init_packets.go
new file mode 100644
index 0000000..b0bc6f5
--- /dev/null
+++ b/internal/encoding/ssh/filexfer/init_packets.go
@@ -0,0 +1,99 @@
+package filexfer
+
+// InitPacket defines the SSH_FXP_INIT packet.
+type InitPacket struct {
+	Version    uint32
+	Extensions []*ExtensionPair
+}
+
+// MarshalBinary returns p as the binary encoding of p.
+func (p *InitPacket) MarshalBinary() ([]byte, error) {
+	size := 1 + 4 // byte(type) + uint32(version)
+
+	for _, ext := range p.Extensions {
+		size += ext.Len()
+	}
+
+	b := NewBuffer(make([]byte, 4, 4+size))
+	b.AppendUint8(uint8(PacketTypeInit))
+	b.AppendUint32(p.Version)
+
+	for _, ext := range p.Extensions {
+		ext.MarshalInto(b)
+	}
+
+	b.PutLength(size)
+
+	return b.Bytes(), nil
+}
+
+// UnmarshalBinary unmarshals a full raw packet out of the given data.
+// It is assumed that the uint32(length) has already been consumed to receive the data.
+// It is also assumed that the uint8(type) has already been consumed to which packet to unmarshal into.
+func (p *InitPacket) UnmarshalBinary(data []byte) (err error) {
+	buf := NewBuffer(data)
+
+	if p.Version, err = buf.ConsumeUint32(); err != nil {
+		return err
+	}
+
+	for buf.Len() > 0 {
+		var ext ExtensionPair
+		if err := ext.UnmarshalFrom(buf); err != nil {
+			return err
+		}
+
+		p.Extensions = append(p.Extensions, &ext)
+	}
+
+	return nil
+}
+
+// VersionPacket defines the SSH_FXP_VERSION packet.
+type VersionPacket struct {
+	Version    uint32
+	Extensions []*ExtensionPair
+}
+
+// MarshalBinary returns p as the binary encoding of p.
+func (p *VersionPacket) MarshalBinary() ([]byte, error) {
+	size := 1 + 4 // byte(type) + uint32(version)
+
+	for _, ext := range p.Extensions {
+		size += ext.Len()
+	}
+
+	b := NewBuffer(make([]byte, 4, 4+size))
+	b.AppendUint8(uint8(PacketTypeVersion))
+	b.AppendUint32(p.Version)
+
+	for _, ext := range p.Extensions {
+		ext.MarshalInto(b)
+	}
+
+	b.PutLength(size)
+
+	return b.Bytes(), nil
+}
+
+// UnmarshalBinary unmarshals a full raw packet out of the given data.
+// It is assumed that the uint32(length) has already been consumed to receive the data.
+// It is also assumed that the uint8(type) has already been consumed to which packet to unmarshal into.
+func (p *VersionPacket) UnmarshalBinary(data []byte) (err error) {
+	buf := NewBuffer(data)
+
+	if p.Version, err = buf.ConsumeUint32(); err != nil {
+		return err
+	}
+
+	for buf.Len() > 0 {
+		var ext ExtensionPair
+		if err := ext.UnmarshalFrom(buf); err != nil {
+			return err
+		}
+
+		p.Extensions = append(p.Extensions, &ext)
+	}
+
+	return nil
+}