Refuse credentials in a storage URL's endpoint or rclone remote name (closes #322)

storage_url refused only the outer URL's userinfo and unknown query
parameters. Userinfo inside the s3 endpoint= value, and rclone's
remote,param=value parameters in the remote name, were accepted and
then printed by info, remote info and snapshot create. Both are now
refused when the storage URL is parsed, without echoing the value: a
host name never contains "@", and an rclone remote name never contains
a comma. The rclone case has its own error pointing at rclone config,
since the existing credentials error names the s3.* keys.

Model: opus-5-5

internal/storage/url.go

@@ -29,7 +29,10 @@ var (
 	ErrURLCredentials     = errors.New(
 		"storage URL must not carry credentials; " +
 			"set s3.access_key_id and s3.secret_access_key in the config instead")
-	ErrURLUnknownParam = errors.New("unknown query parameter in storage URL")
+	ErrURLUnknownParam    = errors.New("unknown query parameter in storage URL")
+	ErrRcloneRemoteParams = errors.New(
+		"rclone URL must not carry parameters in the remote name; " +
+			"set them on the remote with rclone config instead")
 )
 
 // URL represents a parsed storage URL.
@@ -90,8 +93,9 @@ func parseFileURL(rawPath string) (*URL, error) {
 }
 
 // parseS3URL parses an s3://bucket/prefix URL. It rejects credentials in
-// the userinfo and any query parameter other than endpoint, region and
-// ssl, so a credential-bearing URL is never stored or echoed.
+// the userinfo or in the endpoint parameter's userinfo, and any query
+// parameter other than endpoint, region and ssl, so a credential-bearing
+// URL is never stored or echoed.
 func parseS3URL(rawURL string) (*URL, error) {
 	u, err := url.Parse(rawURL)
 	if err != nil {
@@ -114,6 +118,14 @@ func parseS3URL(rawURL string) (*URL, error) {
 		return nil, err
 	}
 
+	// A host name never contains "@", so one in an endpoint, with or
+	// without a scheme, can only introduce userinfo.
+	for _, endpoint := range query["endpoint"] {
+		if strings.Contains(endpoint, "@") {
+			return nil, ErrURLCredentials
+		}
+	}
+
 	return &URL{
 		Scheme:   schemeS3,
 		Bucket:   bucket,
@@ -125,8 +137,9 @@ func parseS3URL(rawURL string) (*URL, error) {
 }
 
 // parseRcloneURL parses an rclone://remote/path URL. rclone:// takes no
-// query parameters, so credentials in the userinfo and any parameter at
-// all are rejected rather than silently ignored.
+// query parameters, so credentials in the userinfo, parameters in the
+// remote name and any query parameter at all are rejected rather than
+// silently ignored.
 func parseRcloneURL(rawURL string) (*URL, error) {
 	u, err := url.Parse(rawURL)
 	if err != nil {
@@ -142,6 +155,12 @@ func parseRcloneURL(rawURL string) (*URL, error) {
 		return nil, ErrMissingRemote
 	}
 
+	// An rclone remote name never contains a comma; one starts rclone's
+	// remote,param=value form, whose values can be credentials.
+	if strings.Contains(remote, ",") {
+		return nil, ErrRcloneRemoteParams
+	}
+
 	err = rejectUnknownParams(u.Query())
 	if err != nil {
 		return nil, err

internal/storage/url_parse_test.go

@@ -150,6 +150,18 @@ func TestParseStorageURLRejectsCredentials(t *testing.T) {
 			wantErr: storage.ErrURLCredentials,
 			secrets: []string{key, secret, "mybucket"},
 		},
+		{
+			name:    "s3 userinfo in endpoint",
+			raw:     "s3://mybucket?endpoint=https://" + key + ":" + secret + "@minio.example.com",
+			wantErr: storage.ErrURLCredentials,
+			secrets: []string{key, secret},
+		},
+		{
+			name:    "s3 userinfo in endpoint without scheme",
+			raw:     "s3://mybucket?endpoint=" + key + ":" + secret + "@minio.example.com",
+			wantErr: storage.ErrURLCredentials,
+			secrets: []string{key, secret},
+		},
 		{
 			name:    "s3 unknown query param",
 			raw:     "s3://mybucket?access_key=" + key + "&secret=" + secret,
@@ -203,6 +215,27 @@ func TestParseStorageURLRejectsCredentials(t *testing.T) {
 	}
 }
 
+// TestParseStorageURLRejectsRcloneRemoteParams checks that an rclone
+// remote name carrying parameters (rclone's "remote,param=value" form,
+// which can hold a credential) is rejected without echoing the value.
+func TestParseStorageURLRejectsRcloneRemoteParams(t *testing.T) {
+	t.Parallel()
+
+	const secret = "topsecret"
+
+	raw := "rclone://gdrive,client_secret=" + secret + "/backups"
+
+	_, err := storage.ParseStorageURL(raw)
+	if !errors.Is(err, storage.ErrRcloneRemoteParams) {
+		t.Fatalf("ParseStorageURL(%q) error = %v, want %v",
+			raw, err, storage.ErrRcloneRemoteParams)
+	}
+
+	if strings.Contains(err.Error(), secret) {
+		t.Errorf("error message leaked %q: %v", secret, err.Error())
+	}
+}
+
 // TestParseStorageURLParseFailureHidesURL checks that when url.Parse
 // itself fails, the wrapped error carries only the inner cause, not the
 // *url.Error whose text embeds the raw (possibly credential-bearing) URL.

internal/vaultik/destination_validation_test.go

@@ -161,14 +161,13 @@ func TestVerifyManifestBlobsRejectsShortHash(t *testing.T) {
 		Blobs: []snapshot.BlobInfo{{Hash: "abc", CompressedSize: 1}},
 	}
 
-	verified, missing, mismatched, missingSize, unchecked, err :=
+	verified, missing, mismatched, missingSize, err :=
 		v.verifyManifestBlobs(manifest, &VerifyOptions{JSON: true})
 	require.ErrorIs(t, err, errInvalidBlobHash)
 	require.Zero(t, verified)
 	require.Zero(t, missing)
 	require.Zero(t, mismatched)
 	require.Zero(t, missingSize)
-	require.Empty(t, unchecked)
 }
 
 // TestVerifyBlobChunksRejectsNegativeLength proves a blob_chunks row with a

internal/vaultik/shallow_verify_test.go

@@ -4,20 +4,15 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
-	"errors"
-	"fmt"
 	"io"
 	"os"
-	"path"
 	"path/filepath"
-	"slices"
 	"testing"
 
 	"github.com/spf13/afero"
 	"github.com/stretchr/testify/require"
 	"sneak.berlin/go/vaultik/internal/log"
 	"sneak.berlin/go/vaultik/internal/snapshot"
-	"sneak.berlin/go/vaultik/internal/storage"
 	"sneak.berlin/go/vaultik/internal/ui"
 	"sneak.berlin/go/vaultik/internal/vaultik"
 )
@@ -156,224 +151,6 @@ func TestShallowVerifyDetectsMissingDatabase(t *testing.T) {
 		"shallow verify must fail when db.zst.age is absent")
 }
 
-// errStatDenied stands in for any storage error other than not-found: a
-// permission error, an S3 403, a dropped connection.
-var errStatDenied = errors.New("injected stat failure")
-
-// statFailingStorer fails Stat with errStatDenied for the keys in
-// failKeys and passes every other call to the wrapped Storer.
-type statFailingStorer struct {
-	storage.Storer
-
-	failKeys []string
-}
-
-func (s statFailingStorer) Stat(
-	ctx context.Context, key string,
-) (*storage.ObjectInfo, error) {
-	if slices.Contains(s.failKeys, key) {
-		return nil, fmt.Errorf("stat %q: %w", key, errStatDenied)
-	}
-
-	return s.Storer.Stat(ctx, key)
-}
-
-// TestShallowVerifyReportsStatErrorsApartFromMissing backs up a real
-// snapshot, deletes one blob, and makes storage fail Stat with an error
-// other than not-found for a second blob and for the encrypted database.
-// Only the deleted blob may be counted as missing. The second blob and
-// the database must be reported as could not be checked, with the error
-// storage returned, and verify must fail, in the text output and under
-// --json.
-func TestShallowVerifyReportsStatErrorsApartFromMissing(t *testing.T) {
-	log.Initialize(log.Config{})
-	t.Parallel()
-
-	fs := afero.NewOsFs()
-	tempDir := t.TempDir()
-
-	dataDir := filepath.Join(tempDir, "source")
-	storeDir := filepath.Join(tempDir, "remote")
-	dbPath := filepath.Join(tempDir, "index.sqlite")
-
-	chunkSize := int64(32 * 1024)
-	maxBlobSize := int64(128 * 1024)
-
-	// Random content, so the snapshot spans several blobs.
-	require.NoError(t, fs.MkdirAll(dataDir, 0o755))
-	appendRandomBytes(t, fs, map[string][]byte{},
-		filepath.Join(dataDir, "data.bin"), maxBlobSize*4)
-
-	ctx := context.Background()
-
-	cfg, storer, snapshotID := runFileStorageBackup(
-		ctx, t, fs, dataDir, storeDir, dbPath, chunkSize, maxBlobSize)
-
-	blobKeys := storedBlobKeys(t, storeDir)
-	require.GreaterOrEqual(t, len(blobKeys), 2, "expected at least two blobs")
-
-	missingKey, uncheckedKey := blobKeys[0], blobKeys[1]
-	missingHash, uncheckedHash := path.Base(missingKey), path.Base(uncheckedKey)
-
-	require.NoError(t, os.Remove(filepath.Join(storeDir, missingKey)))
-
-	dbKey := "metadata/" + snapshot.RemoteSnapshotKey(snapshotID) + "/db.zst.age"
-	failing := statFailingStorer{
-		Storer:   storer,
-		failKeys: []string{uncheckedKey, dbKey},
-	}
-
-	newVerifier := func(out io.Writer) *vaultik.Vaultik {
-		v := &vaultik.Vaultik{
-			Config:  cfg,
-			Storage: failing,
-			Fs:      fs,
-			Stdout:  out,
-			Stderr:  io.Discard,
-			UI:      ui.NewWithColor(io.Discard, false),
-		}
-		v.SetContext(ctx)
-
-		return v
-	}
-
-	var out bytes.Buffer
-
-	err := newVerifier(&out).VerifySnapshotWithOptions(
-		snapshotID, &vaultik.VerifyOptions{JSON: true})
-	require.Error(t, err)
-
-	result := decodeVerifyResult(t, out.Bytes())
-	require.Equal(t, "failed", result.Status)
-	require.Equal(t, 1, result.Missing, "only the deleted blob is missing")
-	require.Equal(t, result.BlobCount-2, result.Verified)
-	require.Len(t, result.Unchecked, 1)
-	require.Equal(t, uncheckedHash, result.Unchecked[0].Hash)
-	require.Contains(t, result.Unchecked[0].Error, errStatDenied.Error())
-	require.False(t, result.DatabaseMissing,
-		"a database that could not be checked is not missing")
-	require.Contains(t, result.DatabaseCheckError, errStatDenied.Error())
-
-	out.Reset()
-	err = newVerifier(&out).VerifySnapshotWithOptions(
-		snapshotID, &vaultik.VerifyOptions{})
-	require.Error(t, err)
-
-	text := out.String()
-	require.Contains(t, text, "Missing: "+missingHash)
-	require.NotContains(t, text, "Missing: "+uncheckedHash)
-	require.Contains(t, text, "Could not check: "+uncheckedHash)
-	require.Contains(t, text, "Encrypted database:       could not be checked")
-	require.Contains(t, text, errStatDenied.Error())
-	require.Contains(t, text, "FAILED")
-}
-
-// TestShallowVerifyQuietFailsOnStatErrorAlone backs up a healthy snapshot,
-// then makes storage fail Stat, with an error other than not-found, for
-// one blob alone and then for the encrypted database alone. Each run must
-// fail verify, and under --quiet, which drops the report, the error
-// storage returned must still reach stderr.
-//
-//nolint:paralleltest // captureProcessStderr replaces os.Stderr
-func TestShallowVerifyQuietFailsOnStatErrorAlone(t *testing.T) {
-	log.Initialize(log.Config{})
-
-	fs := afero.NewOsFs()
-	tempDir := t.TempDir()
-
-	dataDir := filepath.Join(tempDir, "source")
-	storeDir := filepath.Join(tempDir, "remote")
-	dbPath := filepath.Join(tempDir, "index.sqlite")
-
-	chunkSize := int64(32 * 1024)
-	maxBlobSize := int64(128 * 1024)
-
-	require.NoError(t, fs.MkdirAll(dataDir, 0o755))
-	require.NoError(t, afero.WriteFile(fs,
-		filepath.Join(dataDir, "data.bin"),
-		bytesPattern("shallow-quiet-", int(maxBlobSize*2)), 0o644))
-
-	ctx := context.Background()
-
-	cfg, storer, snapshotID := runFileStorageBackup(
-		ctx, t, fs, dataDir, storeDir, dbPath, chunkSize, maxBlobSize)
-
-	newQuietVerifier := func(s storage.Storer) *vaultik.Vaultik {
-		v := &vaultik.Vaultik{
-			Config:  cfg,
-			Storage: s,
-			Fs:      fs,
-			Stdout:  io.Discard,
-			Stderr:  io.Discard,
-			UI:      ui.NewWithColor(io.Discard, false),
-		}
-		v.SetContext(ctx)
-		v.UI.SetQuiet(true)
-
-		return v
-	}
-
-	require.NoError(t,
-		newQuietVerifier(storer).VerifySnapshotWithOptions(
-			snapshotID, &vaultik.VerifyOptions{}),
-		"shallow verify should pass on a healthy snapshot")
-
-	blobKeys := storedBlobKeys(t, storeDir)
-	require.NotEmpty(t, blobKeys)
-
-	dbKey := "metadata/" + snapshot.RemoteSnapshotKey(snapshotID) + "/db.zst.age"
-
-	for _, failKey := range []string{blobKeys[0], dbKey} {
-		v := newQuietVerifier(statFailingStorer{
-			Storer:   storer,
-			failKeys: []string{failKey},
-		})
-
-		var err error
-
-		stderr := captureProcessStderr(t, func() {
-			err = v.VerifySnapshotWithOptions(
-				snapshotID, &vaultik.VerifyOptions{})
-		})
-
-		require.Error(t, err,
-			"verify must fail when %s could not be checked", failKey)
-		require.Contains(t, stderr, errStatDenied.Error(),
-			"under --quiet the error for %s must still reach stderr", failKey)
-	}
-}
-
-// storedBlobKeys returns the storage key of every blob file under
-// storeDir, sorted.
-func storedBlobKeys(t *testing.T, storeDir string) []string {
-	t.Helper()
-
-	var keys []string
-
-	err := filepath.Walk(filepath.Join(storeDir, "blobs"),
-		func(p string, info os.FileInfo, err error) error {
-			if err != nil {
-				return err
-			}
-
-			if info.IsDir() {
-				return nil
-			}
-
-			rel, err := filepath.Rel(storeDir, p)
-			if err != nil {
-				return err
-			}
-
-			keys = append(keys, filepath.ToSlash(rel))
-
-			return nil
-		})
-	require.NoError(t, err)
-
-	return keys
-}
-
 // growOneBlob appends bytes to the first blob file found under blobsDir,
 // changing its on-disk size so it no longer matches the manifest.
 func growOneBlob(t *testing.T, fs afero.Fs, blobsDir string) {

internal/vaultik/snapshot.go

@@ -14,7 +14,6 @@ import (
 
 	"sneak.berlin/go/vaultik/internal/log"
 	"sneak.berlin/go/vaultik/internal/snapshot"
-	"sneak.berlin/go/vaultik/internal/storage"
 	"sneak.berlin/go/vaultik/internal/types"
 )
 
@@ -775,10 +774,18 @@ func (v *Vaultik) VerifySnapshotWithOptions(
 		v.stdoutf("Checking blob presence and sizes...\n")
 	}
 
-	v.checkSnapshotDatabase(remoteKey, result)
+	// A snapshot is only restorable if its encrypted database is present
+	// alongside the blobs. Shallow verify checks that the object exists; it
+	// does not decrypt it (that is deep verify's job).
+	dbPath := fmt.Sprintf("metadata/%s/db.zst.age", remoteKey)
 
-	result.Verified, result.Missing, result.Mismatched, result.MissingSize,
-		result.Unchecked, err = v.verifyManifestBlobs(manifest, opts)
+	_, dbErr := v.Storage.Stat(v.ctx, dbPath)
+	if dbErr != nil {
+		result.DatabaseMissing = true
+	}
+
+	result.Verified, result.Missing, result.Mismatched, result.MissingSize, err =
+		v.verifyManifestBlobs(manifest, opts)
 	if err != nil {
 		if opts.JSON {
 			result.Status = verifyStatusFailed
@@ -815,46 +822,25 @@ func (v *Vaultik) printVerifyHeader(snapshotID string, opts *VerifyOptions) {
 	}
 }
 
-// checkSnapshotDatabase records in result whether the snapshot's
-// encrypted database is missing or could not be checked. A snapshot is
-// only restorable if its database is present alongside the blobs.
-// Shallow verify checks that the object exists; it does not decrypt it
-// (that is deep verify's job).
-func (v *Vaultik) checkSnapshotDatabase(remoteKey string, result *VerifyResult) {
-	dbPath := fmt.Sprintf("metadata/%s/db.zst.age", remoteKey)
-
-	_, err := v.Storage.Stat(v.ctx, dbPath)
-
-	switch {
-	case errors.Is(err, storage.ErrNotFound):
-		result.DatabaseMissing = true
-	case err != nil:
-		result.DatabaseCheckError = err.Error()
-	}
-}
-
 // verifyManifestBlobs checks that each blob in the manifest is present in
 // storage with the size the manifest records, returning the counts of
 // blobs that were present with the right size, absent, and present but the
-// wrong size, the total bytes of the absent blobs, and the blobs it could
-// not check because storage returned an error other than not-found. It
-// does not read blob contents; deep verification (RunDeepVerify) does
-// that. The size comparison matches the deep path (see
-// verifyBlobExistenceFromDB).
+// wrong size, plus the total bytes of the absent blobs. It does not read
+// blob contents; deep verification (RunDeepVerify) does that. The size
+// comparison matches the deep path (see verifyBlobExistenceFromDB).
 func (v *Vaultik) verifyManifestBlobs(
 	manifest *snapshot.Manifest, opts *VerifyOptions,
-) (int, int, int, int64, []UncheckedBlob, error) {
+) (int, int, int, int64, error) {
 	var (
 		verified, missing, mismatched int
 		missingSize                   int64
-		unchecked                     []UncheckedBlob
 	)
 
 	for _, blob := range manifest.Blobs {
 		// The manifest is unauthenticated, so its blob hashes are checked
 		// before being spliced into a storage path.
 		if !isBlobHash(blob.Hash) {
-			return 0, 0, 0, 0, nil, fmt.Errorf("%w: %s",
+			return 0, 0, 0, 0, fmt.Errorf("%w: %s",
 				errInvalidBlobHash, shortHash(blob.Hash))
 		}
 
@@ -863,7 +849,7 @@ func (v *Vaultik) verifyManifestBlobs(
 
 		stat, err := v.Storage.Stat(v.ctx, blobPath)
 		switch {
-		case errors.Is(err, storage.ErrNotFound):
+		case err != nil:
 			if !opts.JSON && !v.UI.Quiet() {
 				v.stdoutf("  Missing: %s (%s)\n",
 					blob.Hash, ubytes(blob.CompressedSize))
@@ -871,13 +857,6 @@ func (v *Vaultik) verifyManifestBlobs(
 
 			missing++
 			missingSize += blob.CompressedSize
-		case err != nil:
-			if !opts.JSON && !v.UI.Quiet() {
-				v.stdoutf("  Could not check: %s (%v)\n", blob.Hash, err)
-			}
-
-			unchecked = append(unchecked,
-				UncheckedBlob{Hash: blob.Hash, Error: err.Error()})
 		case stat.Size != blob.CompressedSize:
 			if !opts.JSON && !v.UI.Quiet() {
 				v.stdoutf("  Wrong size: %s (store has %s, manifest lists %s)\n",
@@ -890,7 +869,7 @@ func (v *Vaultik) verifyManifestBlobs(
 		}
 	}
 
-	return verified, missing, mismatched, missingSize, unchecked, nil
+	return verified, missing, mismatched, missingSize, nil
 }
 
 // formatVerifyResult outputs the final verification results as JSON or
@@ -911,19 +890,9 @@ func (v *Vaultik) formatVerifyResult(
 		return v.outputVerifyJSON(result)
 	}
 
-	// --quiet drops the report but not the errors storage returned, which
-	// are logged on stderr. A failure is still returned either way, and
-	// the cli layer prints it on stderr.
-	if v.UI.Quiet() {
-		for _, blob := range result.Unchecked {
-			log.Warn("Could not check blob", "blob", blob.Hash, "error", blob.Error)
-		}
-
-		if result.DatabaseCheckError != "" {
-			log.Warn("Could not check the encrypted database",
-				"snapshot", result.SnapshotID, "error", result.DatabaseCheckError)
-		}
-	} else {
+	// Under --quiet a failure is still returned, and the cli layer
+	// prints it on stderr.
+	if !v.UI.Quiet() {
 		v.printVerifySummary(result, failure)
 	}
 
@@ -949,19 +918,10 @@ func (v *Vaultik) printVerifySummary(result *VerifyResult, failure string) {
 		v.stdoutf("  Wrong size:               %d blobs\n", result.Mismatched)
 	}
 
-	if len(result.Unchecked) > 0 {
-		v.stdoutf("  Could not check:          %d blobs\n", len(result.Unchecked))
-	}
-
 	if result.DatabaseMissing {
 		v.stdoutf("  Encrypted database:       missing\n")
 	}
 
-	if result.DatabaseCheckError != "" {
-		v.stdoutf("  Encrypted database:       could not be checked (%s)\n",
-			result.DatabaseCheckError)
-	}
-
 	v.stdoutf("  Status:       ")
 
 	if failure != "" {
@@ -989,19 +949,10 @@ func shallowVerifyFailure(result *VerifyResult) string {
 			fmt.Sprintf("%d blobs have the wrong size", result.Mismatched))
 	}
 
-	if len(result.Unchecked) > 0 {
-		parts = append(parts, fmt.Sprintf("%d blobs could not be checked",
-			len(result.Unchecked)))
-	}
-
 	if result.DatabaseMissing {
 		parts = append(parts, "the encrypted database is missing")
 	}
 
-	if result.DatabaseCheckError != "" {
-		parts = append(parts, "the encrypted database could not be checked")
-	}
-
 	return strings.Join(parts, "; ")
 }
 

internal/vaultik/verify.go

@@ -57,25 +57,11 @@ type VerifyResult struct {
 	Missing     int    `json:"missing"`
 	MissingSize int64  `json:"missing_size,omitempty"`
 	Mismatched  int    `json:"mismatched,omitempty"`
-	// Unchecked lists the blobs shallow verify could not check, because
-	// storage answered with an error other than not-found, so whether
-	// they are present is unknown.
-	Unchecked []UncheckedBlob `json:"unchecked,omitempty"`
 	// DatabaseMissing is set by shallow verify when the snapshot's
 	// encrypted database (metadata/<key>/db.zst.age) is absent, which
 	// makes the snapshot unrestorable regardless of the blobs.
-	DatabaseMissing bool `json:"database_missing,omitempty"`
-	// DatabaseCheckError is set by shallow verify to the error storage
-	// returned when the encrypted database could not be checked.
-	DatabaseCheckError string `json:"database_check_error,omitempty"`
-	ErrorMessage       string `json:"error,omitempty"`
-}
-
-// UncheckedBlob is a blob shallow verify could not check, with the error
-// storage returned for it.
-type UncheckedBlob struct {
-	Hash  string `json:"hash"`
-	Error string `json:"error"`
+	DatabaseMissing bool   `json:"database_missing,omitempty"`
+	ErrorMessage    string `json:"error,omitempty"`
 }
 
 // deepVerifyFailure records a failure in the result and returns it appropriately