zones: Machine.WriteWireguardKeys()

Signed-off-by: Alejandro Mery <amery@jpi.io>

pkg/zones/machine_file.go

@@ -1,7 +1,9 @@
 package zones
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"os"
 	"path/filepath"
 
@@ -16,6 +18,25 @@ func (m *Machine) OpenFile(name string, flags int, args ...any) (fs.File, error)
 	return fs.OpenFile(base, fullName, flags, 0644)
 }
 
+// CreateTruncFile creates or truncates a file on the machine's config directory
+func (m *Machine) CreateTruncFile(name string, args ...any) (io.WriteCloser, error) {
+	return m.openWriter(name, os.O_CREATE|os.O_TRUNC, args...)
+}
+
+// CreateFile creates a file on the machine's config directory
+func (m *Machine) CreateFile(name string, args ...any) (io.WriteCloser, error) {
+	return m.openWriter(name, os.O_CREATE, args...)
+}
+
+func (m *Machine) openWriter(name string, flags int, args ...any) (io.WriteCloser, error) {
+	f, err := m.OpenFile(name, os.O_WRONLY|flags, args...)
+	if err != nil {
+		return nil, err
+	}
+
+	return f.(io.WriteCloser), nil
+}
+
 // RemoveFile deletes a file from the machine's config directory
 func (m *Machine) RemoveFile(name string, args ...any) error {
 	base := m.zone.zones.dir
@@ -38,6 +59,19 @@ func (m *Machine) ReadFile(name string, args ...any) ([]byte, error) {
 	return fs.ReadFile(base, fullName)
 }
 
+// WriteStringFile writes the given content to a file on the machine's config directory
+func (m *Machine) WriteStringFile(value string, name string, args ...any) error {
+	f, err := m.CreateTruncFile(name, args...)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	buf := bytes.NewBufferString(value)
+	_, err = buf.WriteTo(f)
+	return err
+}
+
 func (m *Machine) getFilename(name string, args ...any) string {
 	if len(args) > 0 {
 		name = fmt.Sprintf(name, args...)

pkg/zones/machine_rings.go

@@ -3,6 +3,7 @@ package zones
 import (
 	"bytes"
 	"fmt"
+	"io/fs"
 	"os"
 
 	"darvaza.org/core"
@@ -72,6 +73,38 @@ func (m *Machine) tryReadWireguardKeys(ring int) error {
 	}
 }
 
+// WriteWireguardKeys writes the wgN.key/wgN.pub files
+func (m *Machine) WriteWireguardKeys(ring int) error {
+	var err error
+	var key, pub string
+	var ri *RingInfo
+
+	ri, _ = m.getRingInfo(ring)
+	if ri != nil {
+		key = ri.Keys.PrivateKey.String()
+		pub = ri.Keys.PublicKey.String()
+	}
+
+	switch {
+	case key == "":
+		return fs.ErrNotExist
+	case pub == "":
+		pub = ri.Keys.PrivateKey.Public().String()
+	}
+
+	err = m.WriteStringFile(key, "wg%v.key", ring)
+	if err != nil {
+		return err
+	}
+
+	err = m.WriteStringFile(pub, "wg%v.pub", ring)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
 // GetWireguardConfig reads a wgN.conf file
 func (m *Machine) GetWireguardConfig(ring int) (*wireguard.Config, error) {
 	data, err := m.ReadFile("wg%v.conf", ring)