Files
vaultik/internal/vaultik/restore_perms_test.go
T
sneak 32a130eaa2
check / check (pull_request) Successful in 2m40s
Restore files at 0600 and make the blob hash check unskippable (closes #163)
Regular files are now created with O_EXCL at mode 0600 and given their
stored mode only after the content is written and closed, so a file
whose stored mode is restrictive is never briefly readable by other
local users mid-restore. A file whose write or close fails is removed
rather than left partial, and a chmod failure is a user-visible warning
instead of a debug line.

hashVerifyReader.Close now errors when closed before EOF, so a short
read or early close can never obtain a blob whose hash was not verified;
downloadBlobToCache drops the cache entry on any such failure.

verifyFile (--verify) now rejects a restored file with bytes past its
last chunk.

Tests cover each behaviour under umask 022.

Model: opus-4-8
2026-09-22 09:21:23 +00:00

307 lines
8.6 KiB
Go

package vaultik //nolint:testpackage // drives restore through unexported session
import (
"bytes"
"context"
"errors"
"io"
"os"
"path/filepath"
"strings"
"sync"
"syscall"
"testing"
"github.com/spf13/afero"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"sneak.berlin/go/vaultik/internal/config"
"sneak.berlin/go/vaultik/internal/database"
"sneak.berlin/go/vaultik/internal/log"
"sneak.berlin/go/vaultik/internal/snapshot"
"sneak.berlin/go/vaultik/internal/storage"
"sneak.berlin/go/vaultik/internal/ui"
)
// errSpyWrite is the injected write failure used to exercise the
// partial-file cleanup path.
var errSpyWrite = errors.New("injected write failure")
// modeSpyFs wraps a real filesystem so restore tests can observe and
// perturb the single output file whose path contains watch. It records
// the on-disk permission bits seen at the moment content is first
// written (the window during which another local user could read it),
// and can inject a write failure or append trailing bytes on close.
type modeSpyFs struct {
afero.Fs
watch string
mu sync.Mutex
writeModes []os.FileMode
failWrite bool
trailing int
}
//nolint:ireturn // afero.Fs.OpenFile is defined to return the interface
func (m *modeSpyFs) OpenFile(
name string, flag int, perm os.FileMode,
) (afero.File, error) {
f, err := m.Fs.OpenFile(name, flag, perm)
if err != nil || !strings.Contains(name, m.watch) {
return f, err
}
return &modeSpyFile{File: f, fs: m, path: name}, nil
}
type modeSpyFile struct {
afero.File
fs *modeSpyFs
path string
written bool
}
func (f *modeSpyFile) Write(p []byte) (int, error) {
if !f.written {
f.written = true
info, err := f.fs.Stat(f.path)
if err == nil {
f.fs.mu.Lock()
f.fs.writeModes = append(f.fs.writeModes, info.Mode().Perm())
f.fs.mu.Unlock()
}
}
if f.fs.failWrite {
return 0, errSpyWrite
}
return f.File.Write(p)
}
func (f *modeSpyFile) Close() error {
if f.fs.trailing > 0 {
_, _ = f.File.Write(bytes.Repeat([]byte{'x'}, f.fs.trailing))
}
return f.File.Close()
}
// backupOneFile writes a single source file with the given mode and
// backs it up into a fresh file storer, returning everything a restore
// needs. The index database is closed before returning so the restore
// half runs from the exported metadata and remote bytes only.
func backupOneFile(
ctx context.Context, t *testing.T, fs afero.Fs, tempDir, name string,
content []byte, mode os.FileMode,
) (*config.Config, *storage.FileStorer, string, string) {
t.Helper()
dataDir := filepath.Join(tempDir, "src")
require.NoError(t, fs.MkdirAll(dataDir, 0o755))
srcPath := filepath.Join(dataDir, name)
require.NoError(t, afero.WriteFile(fs, srcPath, content, mode))
require.NoError(t, fs.Chmod(srcPath, mode))
storeDir := filepath.Join(tempDir, "remote")
dbPath := filepath.Join(tempDir, "index.sqlite")
storer, err := storage.NewFileStorer(storeDir)
require.NoError(t, err)
cfg := &config.Config{
AgeRecipients: []string{
"age1ezrjmfpwsc95svdg0y54mums3zevgzu0x0ecq2f7tp8a05gl0sjq9q9wjg",
},
AgeSecretKey: "AGE-SECRET-KEY-19CR5YSFW59HM4TLD6GXVEDMZFTVVF7PPHKU" +
"T68TXSFPK7APHXA2QS2NJA5",
CompressionLevel: 3,
Hostname: "test-host",
BlobSizeLimit: config.Size(5 * 1024 * 1024),
}
db, err := database.New(ctx, dbPath)
require.NoError(t, err)
repos := database.NewRepositories(db)
sm := snapshot.NewSnapshotManager(snapshot.SnapshotManagerParams{
Repos: repos,
Storage: storer,
Config: cfg,
})
sm.SetFilesystem(fs)
scanner := snapshot.NewScanner(snapshot.ScannerConfig{
FS: fs,
Storage: storer,
ChunkSize: 4 * 1024 * 1024,
MaxBlobSize: 5 * 1024 * 1024,
CompressionLevel: cfg.CompressionLevel,
AgeRecipients: cfg.AgeRecipients,
Repositories: repos,
})
snapshotID, err := sm.CreateSnapshotWithName(
ctx, cfg.Hostname, "perms", "test-version", "test-git")
require.NoError(t, err)
_, err = scanner.Scan(ctx, dataDir, snapshotID)
require.NoError(t, err)
require.NoError(t, sm.CompleteSnapshot(ctx, snapshotID))
require.NoError(t, sm.ExportSnapshotMetadata(ctx, dbPath, snapshotID))
require.NoError(t, db.Close())
return cfg, storer, snapshotID, srcPath
}
// restoredPathFor returns where backupOneFile's source lands under a
// restore target: restore recreates each file at its original absolute
// path beneath TargetDir.
func restoredPathFor(restoreDir, srcPath string) string {
return filepath.Join(restoreDir, srcPath)
}
// withUmask022 forces the process umask to 022 for the duration of a
// test, so the difference between a 0600 create and a default create is
// observable. Restored serially (no t.Parallel) so it does not race
// other tests.
func withUmask022(t *testing.T) {
t.Helper()
old := syscall.Umask(0o022)
t.Cleanup(func() { syscall.Umask(old) })
}
// TestRestoreCreatesFileNeverWiderThanStoredMode checks that a file with
// a restrictive stored mode (0600) is never observable with a wider mode
// while its content is being written, and ends at its stored mode.
//
//nolint:paralleltest // sets the process umask; must run serially
func TestRestoreCreatesFileNeverWiderThanStoredMode(t *testing.T) {
log.Initialize(log.Config{})
withUmask022(t)
fs := afero.NewOsFs()
tempDir := t.TempDir()
ctx := context.Background()
content := randomBytes(t, 4096)
cfg, storer, snapshotID, srcPath := backupOneFile(
ctx, t, fs, tempDir, "secret.bin", content, 0o600)
restoreDir := filepath.Join(tempDir, "restored")
spy := &modeSpyFs{Fs: fs, watch: "secret.bin"}
v := newRestoreVaultik(ctx, cfg, storer, spy)
require.NoError(t, v.Restore(&RestoreOptions{
SnapshotID: snapshotID,
TargetDir: restoreDir,
}))
spy.mu.Lock()
observed := append([]os.FileMode(nil), spy.writeModes...)
spy.mu.Unlock()
require.NotEmpty(t, observed,
"spy never saw the output file being written")
for _, m := range observed {
assert.Equalf(t, os.FileMode(0o600), m,
"file was observable at mode %o during write; must be 0600", m)
}
// The stored mode is applied after the content is written.
info, err := fs.Stat(restoredPathFor(restoreDir, srcPath))
require.NoError(t, err)
assert.Equal(t, os.FileMode(0o600), info.Mode().Perm())
got, err := afero.ReadFile(fs, restoredPathFor(restoreDir, srcPath))
require.NoError(t, err)
require.True(t, bytes.Equal(got, content))
}
// TestRestoreRemovesPartialFileOnWriteFailure checks that a file whose
// content write fails is not left behind.
//
//nolint:paralleltest // sets the process umask; must run serially
func TestRestoreRemovesPartialFileOnWriteFailure(t *testing.T) {
log.Initialize(log.Config{})
withUmask022(t)
fs := afero.NewOsFs()
tempDir := t.TempDir()
ctx := context.Background()
cfg, storer, snapshotID, srcPath := backupOneFile(
ctx, t, fs, tempDir, "doomed.bin", randomBytes(t, 4096), 0o600)
restoreDir := filepath.Join(tempDir, "restored")
spy := &modeSpyFs{Fs: fs, watch: "doomed.bin", failWrite: true}
v := newRestoreVaultik(ctx, cfg, storer, spy)
err := v.Restore(&RestoreOptions{
SnapshotID: snapshotID,
TargetDir: restoreDir,
})
require.Error(t, err, "restore should fail when the write fails")
exists, err := afero.Exists(fs, restoredPathFor(restoreDir, srcPath))
require.NoError(t, err)
assert.False(t, exists, "partial file must be removed after a failed write")
}
// TestVerifyRejectsTrailingBytes checks that --verify fails a restored
// file that has bytes past its last chunk.
//
//nolint:paralleltest // sets the process umask; must run serially
func TestVerifyRejectsTrailingBytes(t *testing.T) {
log.Initialize(log.Config{})
withUmask022(t)
fs := afero.NewOsFs()
tempDir := t.TempDir()
ctx := context.Background()
cfg, storer, snapshotID, _ := backupOneFile(
ctx, t, fs, tempDir, "padded.bin", randomBytes(t, 4096), 0o600)
restoreDir := filepath.Join(tempDir, "restored")
// Append one byte to the file as it is written, so its content still
// matches the stored chunks but it is one byte too long.
spy := &modeSpyFs{Fs: fs, watch: "padded.bin", trailing: 1}
v := newRestoreVaultik(ctx, cfg, storer, spy)
err := v.Restore(&RestoreOptions{
SnapshotID: snapshotID,
TargetDir: restoreDir,
Verify: true,
})
require.Error(t, err, "verify should fail on a file with trailing bytes")
assert.ErrorIs(t, err, errFilesFailedVerify)
}
// newRestoreVaultik builds a Vaultik wired for a restore-only test.
func newRestoreVaultik(
ctx context.Context, cfg *config.Config, storer storage.Storer, fs afero.Fs,
) *Vaultik {
v := &Vaultik{
Config: cfg,
Storage: storer,
Fs: fs,
Stdout: io.Discard,
Stderr: io.Discard,
UI: ui.NewWithColor(io.Discard, false),
}
v.SetContext(ctx)
return v
}