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Restructure modules (#1572)

Browse Source 
* Move portbase into monorepo

* Add new simple module mgr

* [WIP] Switch to new simple module mgr

* Add StateMgr and more worker variants

* [WIP] Switch more modules

* [WIP] Switch more modules

* [WIP] swtich more modules

* [WIP] switch all SPN modules

* [WIP] switch all service modules

* [WIP] Convert all workers to the new module system

* [WIP] add new task system to module manager

* [WIP] Add second take for scheduling workers

* [WIP] Add FIXME for bugs in new scheduler

* [WIP] Add minor improvements to scheduler

* [WIP] Add new worker scheduler

* [WIP] Fix more bug related to new module system

* [WIP] Fix start handing of the new module system

* [WIP] Improve startup process

* [WIP] Fix minor issues

* [WIP] Fix missing subsystem in settings

* [WIP] Initialize managers in constructor

* [WIP] Move module event initialization to constrictors

* [WIP] Fix setting for enabling and disabling the SPN module

* [WIP] Move API registeration into module construction

* [WIP] Update states mgr for all modules

* [WIP] Add CmdLine operation support

* Add state helper methods to module group and instance

* Add notification and module status handling to status package

* Fix starting issues

* Remove pilot widget and update security lock to new status data

* Remove debug logs

* Improve http server shutdown

* Add workaround for cleanly shutting down firewall+netquery

* Improve logging

* Add syncing states with notifications for new module system

* Improve starting, stopping, shutdown; resolve FIXMEs/TODOs

* [WIP] Fix most unit tests

* Review new module system and fix minor issues

* Push shutdown and restart events again via API

* Set sleep mode via interface

* Update example/template module

* [WIP] Fix spn/cabin unit test

* Remove deprecated UI elements

* Make log output more similar for the logging transition phase

* Switch spn hub and observer cmds to new module system

* Fix log sources

* Make worker mgr less error prone

* Fix tests and minor issues

* Fix observation hub

* Improve shutdown and restart handling

* Split up big connection.go source file

* Move varint and dsd packages to structures repo

* Improve expansion test

* Fix linter warnings

* Fix interception module on windows

* Fix linter errors

---------

Co-authored-by: Vladimir Stoilov <vladimir@safing.io>
This commit is contained in:
Daniel Hååvi
2024-08-09 17:15:48 +02:00
committed by GitHub
parent 10a77498f4
commit 80664d1a27
647 changed files with 37690 additions and 3366 deletions
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202
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This is a fork of the github.com/google/renameio Go package at commit 353f8196982447d8b12c64f69530e657331e3dbc.
The inital commit of this package will carry the original package contents.
The Original License is the Apache License in Version 2.0 and the copyright of the forked package is held by Google Inc.
Any changes are recorded in the git history, which is part of this project.
---
The `renameio` Go package provides a way to atomically create or replace a file or
symbolic link.
## Atomicity vs durability
`renameio` concerns itself *only* with atomicity, i.e. making sure applications
never see unexpected file content (a half-written file, or a 0-byte file).
As a practical example, consider https://manpages.debian.org/: if there is a
power outage while the site is updating, we are okay with losing the manpages
which were being rendered at the time of the power outage. They will be added in
a later run of the software. We are not okay with having a manpage replaced by a
0-byte file under any circumstances, though.
## Advantages of this package
There are other packages for atomically replacing files, and sometimes ad-hoc
implementations can be found in programs.
A naive approach to the problem is to create a temporary file followed by a call
to `os.Rename()`. However, there are a number of subtleties which make the
correct sequence of operations hard to identify:
* The temporary file should be removed when an error occurs, but a remove must
not be attempted if the rename succeeded, as a new file might have been
created with the same name. This renders a throwaway `defer
os.Remove(t.Name())` insufficient; state must be kept.
* The temporary file must be created on the same file system (same mount point)
for the rename to work, but the TMPDIR environment variable should still be
respected, e.g. to direct temporary files into a separate directory outside of
the webserver’s document root but on the same file system.
* On POSIX operating systems, the
[`fsync`](https://manpages.debian.org/stretch/manpages-dev/fsync.2) system
call must be used to ensure that the `os.Rename()` call will not result in a
0-length file.
This package attempts to get all of these details right, provides an intuitive,
yet flexible API and caters to use-cases where high performance is required.
## Disclaimer
This is not an official Google product (experimental or otherwise), it
is just code that happens to be owned by Google.
This project is not affiliated with the Go project.

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// Package renameio provides a way to atomically create or replace a file or
// symbolic link.
//
// Caveat: this package requires the file system rename(2) implementation to be
// atomic. Notably, this is not the case when using NFS with multiple clients:
// https://stackoverflow.com/a/41396801
package renameio

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package renameio_test
import (
"fmt"
"log"
"github.com/safing/portmaster/base/utils/renameio"
)
func ExampleTempFile_justone() { //nolint:testableexamples
persist := func(temperature float64) error {
t, err := renameio.TempFile("", "/srv/www/metrics.txt")
if err != nil {
return err
}
defer func() {
_ = t.Cleanup()
}()
if _, err := fmt.Fprintf(t, "temperature_degc %f\n", temperature); err != nil {
return err
}
return t.CloseAtomicallyReplace()
}
// Thanks to the write package, a webserver exposing /srv/www never
// serves an incomplete or missing file.
if err := persist(31.2); err != nil {
log.Fatal(err)
}
}
func ExampleTempFile_many() { //nolint:testableexamples
// Prepare for writing files to /srv/www, effectively caching calls to
// TempDir which TempFile would otherwise need to make.
dir := renameio.TempDir("/srv/www")
persist := func(temperature float64) error {
t, err := renameio.TempFile(dir, "/srv/www/metrics.txt")
if err != nil {
return err
}
defer func() {
_ = t.Cleanup()
}()
if _, err := fmt.Fprintf(t, "temperature_degc %f\n", temperature); err != nil {
return err
}
return t.CloseAtomicallyReplace()
}
// Imagine this was an endless loop, reading temperature sensor values.
// Thanks to the write package, a webserver exposing /srv/www never
// serves an incomplete or missing file.
for {
if err := persist(31.2); err != nil {
log.Fatal(err)
}
}
}

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//go:build darwin || dragonfly || freebsd || linux || nacl || netbsd || openbsd || solaris || windows
package renameio
import (
"bytes"
"os"
"path/filepath"
"testing"
)
func TestSymlink(t *testing.T) {
t.Parallel()
d, err := os.MkdirTemp("", "test-renameio-testsymlink")
if err != nil {
t.Fatal(err)
}
t.Cleanup(func() {
_ = os.RemoveAll(d)
})
want := []byte("Hello World")
if err := os.WriteFile(filepath.Join(d, "hello.txt"), want, 0o0600); err != nil {
t.Fatal(err)
}
for range 2 {
if err := Symlink("hello.txt", filepath.Join(d, "hi.txt")); err != nil {
t.Fatal(err)
}
got, err := os.ReadFile(filepath.Join(d, "hi.txt"))
if err != nil {
t.Fatal(err)
}
if !bytes.Equal(got, want) {
t.Fatalf("unexpected content: got %q, want %q", string(got), string(want))
}
}
}

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package renameio
import (
"errors"
"io/fs"
"os"
"path/filepath"
)
// TempDir checks whether os.TempDir() can be used as a temporary directory for
// later atomically replacing files within dest. If no (os.TempDir() resides on
// a different mount point), dest is returned.
//
// Note that the returned value ceases to be valid once either os.TempDir()
// changes (e.g. on Linux, once the TMPDIR environment variable changes) or the
// file system is unmounted.
func TempDir(dest string) string {
return tempDir("", filepath.Join(dest, "renameio-TempDir"))
}
func tempDir(dir, dest string) string {
if dir != "" {
return dir // caller-specified directory always wins
}
// Chose the destination directory as temporary directory so that we
// definitely can rename the file, for which both temporary and destination
// file need to point to the same mount point.
fallback := filepath.Dir(dest)
// The user might have overridden the os.TempDir() return value by setting
// the TMPDIR environment variable.
tmpdir := os.TempDir()
testsrc, err := os.CreateTemp(tmpdir, "."+filepath.Base(dest))
if err != nil {
return fallback
}
cleanup := true
defer func() {
if cleanup {
_ = os.Remove(testsrc.Name())
}
}()
_ = testsrc.Close()
testdest, err := os.CreateTemp(filepath.Dir(dest), "."+filepath.Base(dest))
if err != nil {
return fallback
}
defer func() {
_ = os.Remove(testdest.Name())
}()
_ = testdest.Close()
if err := os.Rename(testsrc.Name(), testdest.Name()); err != nil {
return fallback
}
cleanup = false // testsrc no longer exists
return tmpdir
}
// PendingFile is a pending temporary file, waiting to replace the destination
// path in a call to CloseAtomicallyReplace.
type PendingFile struct {
*os.File
path string
done bool
closed bool
}
// Cleanup is a no-op if CloseAtomicallyReplace succeeded, and otherwise closes
// and removes the temporary file.
func (t *PendingFile) Cleanup() error {
if t.done {
return nil
}
// An error occurred. Close and remove the tempfile. Errors are returned for
// reporting, there is nothing the caller can recover here.
var closeErr error
if !t.closed {
closeErr = t.Close()
}
if err := os.Remove(t.Name()); err != nil {
return err
}
return closeErr
}
// CloseAtomicallyReplace closes the temporary file and atomically replaces
// the destination file with it, i.e., a concurrent open(2) call will either
// open the file previously located at the destination path (if any), or the
// just written file, but the file will always be present.
func (t *PendingFile) CloseAtomicallyReplace() error {
// Even on an ordered file system (e.g. ext4 with data=ordered) or file
// systems with write barriers, we cannot skip the fsync(2) call as per
// Theodore Ts'o (ext2/3/4 lead developer):
//
// > data=ordered only guarantees the avoidance of stale data (e.g., the previous
// > contents of a data block showing up after a crash, where the previous data
// > could be someone's love letters, medical records, etc.). Without the fsync(2)
// > a zero-length file is a valid and possible outcome after the rename.
if err := t.Sync(); err != nil {
return err
}
t.closed = true
if err := t.Close(); err != nil {
return err
}
if err := os.Rename(t.Name(), t.path); err != nil {
return err
}
t.done = true
return nil
}
// TempFile wraps os.CreateTemp for the use case of atomically creating or
// replacing the destination file at path.
//
// If dir is the empty string, TempDir(filepath.Base(path)) is used. If you are
// going to write a large number of files to the same file system, store the
// result of TempDir(filepath.Base(path)) and pass it instead of the empty
// string.
//
// The file's permissions will be 0600 by default. You can change these by
// explicitly calling Chmod on the returned PendingFile.
func TempFile(dir, path string) (*PendingFile, error) {
f, err := os.CreateTemp(tempDir(dir, path), "."+filepath.Base(path))
if err != nil {
return nil, err
}
return &PendingFile{File: f, path: path}, nil
}
// Symlink wraps os.Symlink, replacing an existing symlink with the same name
// atomically (os.Symlink fails when newname already exists, at least on Linux).
func Symlink(oldname, newname string) error {
// Fast path: if newname does not exist yet, we can skip the whole dance
// below.
if err := os.Symlink(oldname, newname); err == nil || !errors.Is(err, fs.ErrExist) {
return err
}
// We need to use os.MkdirTemp, as we cannot overwrite a os.CreateTemp,
// and removing+symlinking creates a TOCTOU race.
d, err := os.MkdirTemp(filepath.Dir(newname), "."+filepath.Base(newname))
if err != nil {
return err
}
cleanup := true
defer func() {
if cleanup {
_ = os.RemoveAll(d)
}
}()
symlink := filepath.Join(d, "tmp.symlink")
if err := os.Symlink(oldname, symlink); err != nil {
return err
}
if err := os.Rename(symlink, newname); err != nil {
return err
}
cleanup = false
return os.RemoveAll(d)
}

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//go:build linux
package renameio
import (
"os"
"path/filepath"
"syscall"
"testing"
)
func TestTempDir(t *testing.T) {
t.Parallel()
if tmpdir, ok := os.LookupEnv("TMPDIR"); ok {
t.Cleanup(func() {
_ = os.Setenv("TMPDIR", tmpdir) // restore
})
} else {
t.Cleanup(func() {
_ = os.Unsetenv("TMPDIR") // restore
})
}
mount1, err := os.MkdirTemp("", "test-renameio-testtempdir1")
if err != nil {
t.Fatal(err)
}
t.Cleanup(func() {
_ = os.RemoveAll(mount1)
})
mount2, err := os.MkdirTemp("", "test-renameio-testtempdir2")
if err != nil {
t.Fatal(err)
}
t.Cleanup(func() {
_ = os.RemoveAll(mount2)
})
if err := syscall.Mount("tmpfs", mount1, "tmpfs", 0, ""); err != nil {
t.Skipf("cannot mount tmpfs on %s: %v", mount1, err)
}
t.Cleanup(func() {
_ = syscall.Unmount(mount1, 0)
})
if err := syscall.Mount("tmpfs", mount2, "tmpfs", 0, ""); err != nil {
t.Skipf("cannot mount tmpfs on %s: %v", mount2, err)
}
t.Cleanup(func() {
_ = syscall.Unmount(mount2, 0)
})
tests := []struct {
name string
dir string
path string
TMPDIR string
want string
}{
{
name: "implicit TMPDIR",
path: filepath.Join(os.TempDir(), "foo.txt"),
want: os.TempDir(),
},
{
name: "explicit TMPDIR",
path: filepath.Join(mount1, "foo.txt"),
TMPDIR: mount1,
want: mount1,
},
{
name: "explicit unsuitable TMPDIR",
path: filepath.Join(mount1, "foo.txt"),
TMPDIR: mount2,
want: mount1,
},
{
name: "nonexistant TMPDIR",
path: filepath.Join(mount1, "foo.txt"),
TMPDIR: "/nonexistant",
want: mount1,
},
{
name: "caller-specified",
dir: "/overridden",
path: filepath.Join(mount1, "foo.txt"),
TMPDIR: "/nonexistant",
want: "/overridden",
},
}
for _, testCase := range tests {
t.Run(testCase.name, func(t *testing.T) {
t.Parallel()
if testCase.TMPDIR == "" {
_ = os.Unsetenv("TMPDIR")
} else {
_ = os.Setenv("TMPDIR", testCase.TMPDIR)
}
if got := tempDir(testCase.dir, testCase.path); got != testCase.want {
t.Fatalf("tempDir(%q, %q): got %q, want %q", testCase.dir, testCase.path, got, testCase.want)
}
})
}
}

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package renameio
import "os"
// WriteFile mirrors os.WriteFile, replacing an existing file with the same
// name atomically.
func WriteFile(filename string, data []byte, perm os.FileMode) error {
t, err := TempFile("", filename)
if err != nil {
return err
}
defer func() {
_ = t.Cleanup()
}()
// Set permissions before writing data, in case the data is sensitive.
if err := t.Chmod(perm); err != nil {
return err
}
if _, err := t.Write(data); err != nil {
return err
}
return t.CloseAtomicallyReplace()
}

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//go:build darwin || dragonfly || freebsd || linux || nacl || netbsd || openbsd || solaris || windows
package renameio
import (
"bytes"
"os"
"path/filepath"
"testing"
)
func TestWriteFile(t *testing.T) {
t.Parallel()
d, err := os.MkdirTemp("", "test-renameio-testwritefile")
if err != nil {
t.Fatal(err)
}
defer func() {
_ = os.RemoveAll(d)
}()
filename := filepath.Join(d, "hello.sh")
wantData := []byte("#!/bin/sh\necho \"Hello World\"\n")
wantPerm := os.FileMode(0o0600)
if err := WriteFile(filename, wantData, wantPerm); err != nil {
t.Fatal(err)
}
gotData, err := os.ReadFile(filename)
if err != nil {
t.Fatal(err)
}
if !bytes.Equal(gotData, wantData) {
t.Errorf("got data %v, want data %v", gotData, wantData)
}
fi, err := os.Stat(filename)
if err != nil {
t.Fatal(err)
}
if gotPerm := fi.Mode() & os.ModePerm; gotPerm != wantPerm {
t.Errorf("got permissions 0%o, want permissions 0%o", gotPerm, wantPerm)
}
}