Move github.com/elastic/beats/v7/libbeat/keystore and github.com/elastic/beats/v7/libbeat/common/file.FileInfo (#20)

Author: kvch

README.md

@@ -10,6 +10,7 @@ Provided packages:
 * `github.com/elastic/elastic-agent-libs/cloudid` is used for parsing `cloud.id` and `cloud.auth` when connecting to the Elastic stack.
 * `github.com/elastic/elastic-agent-libs/config` the previous `config.go` file from `github.com/elastic/beats/v7/libbeat/common`. A minimal wrapper around `github.com/elastic/go-ucfg`. It contains helpers for merging and accessing configuration objects and flags.
 * `github.com/elastic/elastic-agent-libs/file` is responsible for rotating and writing input and output files.
+* `github.com/elastic/elastic-agent-libs/keystore` interface for keystores and file keystore implementation.
 * `github.com/elastic/elastic-agent-libs/logp` is the well known logger from libbeat.
 * `github.com/elastic/elastic-agent-libs/logp/cfgwarn` provides logging utilities for warning users about deprecated settings.
 * `github.com/elastic/elastic-agent-libs/mapstr` is the old `github.com/elastic/beats/v7/libbeat/common.MapStr`. It is an extra layer on top of `map[string]interface{}`.

file/fileinfo.go

@@ -0,0 +1,72 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package file
+
+import (
+	"errors"
+	"os"
+)
+
+// A FileInfo describes a file and is returned by Stat and Lstat.
+type FileInfo interface {
+	os.FileInfo
+	UID() (int, error) // UID of the file owner. Returns an error on non-POSIX file systems.
+	GID() (int, error) // GID of the file owner. Returns an error on non-POSIX file systems.
+}
+
+// Stat returns a FileInfo describing the named file.
+// If there is an error, it will be of type *PathError.
+func Stat(name string) (FileInfo, error) {
+	return stat(name, os.Stat)
+}
+
+// Lstat returns a FileInfo describing the named file.
+// If the file is a symbolic link, the returned FileInfo
+// describes the symbolic link. Lstat makes no attempt to follow the link.
+// If there is an error, it will be of type *PathError.
+func Lstat(name string) (FileInfo, error) {
+	return stat(name, os.Lstat)
+}
+
+// Wrap wraps the given os.FileInfo and returns a FileInfo in order to expose
+// the UID and GID in a uniform manner across operating systems.
+func Wrap(info os.FileInfo) (FileInfo, error) {
+	return wrap(info)
+}
+
+type fileInfo struct {
+	os.FileInfo
+	uid *int
+	gid *int
+}
+
+func (f fileInfo) UID() (int, error) {
+	if f.uid == nil {
+		return -1, errors.New("uid not implemented")
+	}
+
+	return *f.uid, nil
+}
+
+func (f fileInfo) GID() (int, error) {
+	if f.gid == nil {
+		return -1, errors.New("gid not implemented")
+	}
+
+	return *f.gid, nil
+}

file/fileinfo_test.go

@@ -0,0 +1,96 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+//go:build !windows && !openbsd
+// +build !windows,!openbsd
+
+// Test for openbsd are excluded here as info.GID() returns 0 instead of the actual value
+// As the code does not seem to be used in any of the beats, this should be ok
+// Still it would be interesting to know why it returns 0.
+
+package file_test
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/elastic/elastic-agent-libs/file"
+)
+
+func TestStat(t *testing.T) {
+	f, err := ioutil.TempFile("", "teststat")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(f.Name())
+
+	link := filepath.Join(os.TempDir(), "teststat-link")
+	if err := os.Symlink(f.Name(), link); err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(link)
+
+	info, err := file.Stat(link)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	require.True(t, info.Mode().IsRegular())
+
+	uid, err := info.UID()
+	if err != nil {
+		t.Fatal(err)
+	}
+	require.EqualValues(t, os.Geteuid(), uid)
+
+	gid, err := info.GID()
+	if err != nil {
+		t.Fatal(err)
+	}
+	require.EqualValues(t, os.Getegid(), gid)
+}
+
+func TestLstat(t *testing.T) {
+	link := filepath.Join(os.TempDir(), "link")
+	if err := os.Symlink("dummy", link); err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(link)
+
+	info, err := file.Lstat(link)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	require.True(t, info.Mode()&os.ModeSymlink > 0)
+
+	uid, err := info.UID()
+	if err != nil {
+		t.Fatal(err)
+	}
+	require.EqualValues(t, os.Geteuid(), uid)
+
+	gid, err := info.GID()
+	if err != nil {
+		t.Fatal(err)
+	}
+	require.EqualValues(t, os.Getegid(), gid)
+}

file/fileinfo_unix.go

@@ -0,0 +1,47 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+//go:build !windows
+// +build !windows
+
+package file
+
+import (
+	"errors"
+	"os"
+	"syscall"
+)
+
+func stat(name string, statFunc func(name string) (os.FileInfo, error)) (FileInfo, error) {
+	info, err := statFunc(name)
+	if err != nil {
+		return nil, err
+	}
+
+	return wrap(info)
+}
+
+func wrap(info os.FileInfo) (FileInfo, error) {
+	stat, ok := info.Sys().(*syscall.Stat_t)
+	if !ok {
+		return nil, errors.New("failed to get uid/gid")
+	}
+
+	uid := int(stat.Uid)
+	gid := int(stat.Gid)
+	return fileInfo{FileInfo: info, uid: &uid, gid: &gid}, nil
+}

file/fileinfo_windows.go

@@ -0,0 +1,35 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package file
+
+import (
+	"os"
+)
+
+func stat(name string, statFunc func(name string) (os.FileInfo, error)) (FileInfo, error) {
+	info, err := statFunc(name)
+	if err != nil {
+		return nil, err
+	}
+
+	return wrap(info)
+}
+
+func wrap(info os.FileInfo) (FileInfo, error) {
+	return fileInfo{FileInfo: info}, nil
+}

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/stretchr/testify v1.7.0
 	go.elastic.co/ecszap v1.0.0
 	go.uber.org/zap v1.21.0
+	golang.org/x/crypto v0.0.0-20210817164053-32db794688a5
 	golang.org/x/sys v0.0.0-20220209214540-3681064d5158
 )
 

go.sum

@@ -384,6 +384,7 @@ golang.org/x/crypto v0.0.0-20190820162420-60c769a6c586/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20190923035154-9ee001bba392/go.mod h1:/lpIB1dKB+9EgE3H3cr1v9wB50oz8l4C4h62xy7jSTY=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20210817164053-32db794688a5 h1:HWj/xjIHfjYU5nVXpTM0s39J9CbLn7Cc5a7IC5rwsMQ=
 golang.org/x/crypto v0.0.0-20210817164053-32db794688a5/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=

keystore/config.go

@@ -0,0 +1,29 @@
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you under
+// the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+package keystore
+
+// Config Define keystore configurable options
+type Config struct {
+	Path string `config:"path"`
+}
+
+func defaultConfig() Config {
+	return Config{
+		Path: "",
+	}
+}