chore: vendor

vendor/github.com/containers/image/pkg/keyctl/key.go

@@ -0,0 +1,65 @@
+// Copyright 2015 Jesse Sipprell. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build linux
+// +build linux
+
+package keyctl
+
+import (
+	"golang.org/x/sys/unix"
+)
+
+// Key represents a single key linked to one or more kernel keyrings.
+type Key struct {
+	Name string
+
+	id, ring keyID
+	size     int
+}
+
+// ID returns the 32-bit kernel identifier for a specific key
+func (k *Key) ID() int32 {
+	return int32(k.id)
+}
+
+// Get the key's value as a byte slice
+func (k *Key) Get() ([]byte, error) {
+	var (
+		b        []byte
+		err      error
+		sizeRead int
+	)
+
+	if k.size == 0 {
+		k.size = 512
+	}
+
+	size := k.size
+
+	b = make([]byte, int(size))
+	sizeRead = size + 1
+	for sizeRead > size {
+		r1, err := unix.KeyctlBuffer(unix.KEYCTL_READ, int(k.id), b, size)
+		if err != nil {
+			return nil, err
+		}
+
+		if sizeRead = int(r1); sizeRead > size {
+			b = make([]byte, sizeRead)
+			size = sizeRead
+			sizeRead = size + 1
+		} else {
+			k.size = sizeRead
+		}
+	}
+	return b[:k.size], err
+}
+
+// Unlink a key from the keyring it was loaded from (or added to). If the key
+// is not linked to any other keyrings, it is destroyed.
+func (k *Key) Unlink() error {
+	_, err := unix.KeyctlInt(unix.KEYCTL_UNLINK, int(k.id), int(k.ring), 0, 0)
+	return err
+}