Add support for new index format

updater/indexes.go

@@ -1,13 +1,97 @@
 package updater
 
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"time"
+)
+
 // Index describes an index file pulled by the updater.
 type Index struct {
 	// Path is the path to the index file
 	// on the update server.
 	Path string
 
+	// Channel holds the release channel name of the index.
+	// It must match the filename without extension.
+	Channel string
+
 	// PreRelease signifies that all versions of this index should be marked as
 	// pre-releases, no matter if the versions actually have a pre-release tag or
 	// not.
 	PreRelease bool
+
+	// LastRelease holds the time of the last seen release of this index.
+	LastRelease time.Time
+}
+
+// IndexFile represents an index file.
+type IndexFile struct {
+	Channel   string
+	Published time.Time
+
+	Releases map[string]string
+}
+
+var (
+	// ErrIndexFromFuture is returned when a signed index is parsed with a
+	// Published timestamp that lies in the future.
+	ErrIndexFromFuture = errors.New("index is from the future")
+
+	// ErrIndexIsOlder is returned when a signed index is parsed with an older
+	// Published timestamp than the current Published timestamp.
+	ErrIndexIsOlder = errors.New("index is older than the current one")
+
+	// ErrIndexChannelMismatch is returned when a signed index is parsed with a
+	// different channel that the expected one.
+	ErrIndexChannelMismatch = errors.New("index does not match the expected channel")
+)
+
+// ParseIndexFile parses an index file and checks if it is valid.
+func ParseIndexFile(indexData []byte, channel string, currentPublished time.Time) (*IndexFile, error) {
+	// Load into struct.
+	indexFile := &IndexFile{}
+	err := json.Unmarshal(indexData, indexFile)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse signed index data: %w", err)
+	}
+
+	// Fallback to old format if there are no releases and no channel is defined.
+	// TODO: Remove in v0.10
+	if len(indexFile.Releases) == 0 && indexFile.Channel == "" {
+		return loadOldIndexFormat(indexData, channel)
+	}
+
+	// Check the index metadata.
+	switch {
+	case !indexFile.Published.IsZero() && time.Now().Before(indexFile.Published):
+		return indexFile, ErrIndexFromFuture
+
+	case !indexFile.Published.IsZero() &&
+		!currentPublished.IsZero() &&
+		currentPublished.After(indexFile.Published):
+		return indexFile, ErrIndexIsOlder
+
+	case channel != "" &&
+		indexFile.Channel != "" &&
+		channel != indexFile.Channel:
+		return indexFile, ErrIndexChannelMismatch
+	}
+
+	return indexFile, nil
+}
+
+func loadOldIndexFormat(indexData []byte, channel string) (*IndexFile, error) {
+	releases := make(map[string]string)
+	err := json.Unmarshal(indexData, &releases)
+	if err != nil {
+		return nil, err
+	}
+
+	return &IndexFile{
+		Channel:   channel,
+		Published: time.Now(),
+		Releases:  releases,
+	}, nil
 }

updater/indexes_test.go

@@ -0,0 +1,55 @@
+package updater
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var (
+	oldFormat = `{
+	"all/ui/modules/assets.zip": "0.3.0",
+	"all/ui/modules/portmaster.zip": "0.2.4",
+	"linux_amd64/core/portmaster-core": "0.8.13"
+}`
+
+	newFormat = `{
+	"Channel": "stable",
+	"Published": "2022-01-02T00:00:00Z",
+	"Releases": {
+		"all/ui/modules/assets.zip": "0.3.0",
+		"all/ui/modules/portmaster.zip": "0.2.4",
+		"linux_amd64/core/portmaster-core": "0.8.13"
+	}
+}`
+
+	formatTestChannel  = "stable"
+	formatTestReleases = map[string]string{
+		"all/ui/modules/assets.zip":        "0.3.0",
+		"all/ui/modules/portmaster.zip":    "0.2.4",
+		"linux_amd64/core/portmaster-core": "0.8.13",
+	}
+)
+
+func TestIndexParsing(t *testing.T) {
+	lastRelease, err := time.Parse(time.RFC3339, "2022-01-01T00:00:00Z")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	oldIndexFile, err := ParseIndexFile([]byte(oldFormat), formatTestChannel, lastRelease)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	newIndexFile, err := ParseIndexFile([]byte(newFormat), formatTestChannel, lastRelease)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	assert.Equal(t, formatTestChannel, oldIndexFile.Channel, "channel should be the same")
+	assert.Equal(t, formatTestChannel, newIndexFile.Channel, "channel should be the same")
+	assert.Equal(t, formatTestReleases, oldIndexFile.Releases, "releases should be the same")
+	assert.Equal(t, formatTestReleases, newIndexFile.Releases, "releases should be the same")
+}

updater/registry.go

@@ -3,7 +3,9 @@ package updater
 import (
 	"fmt"
 	"os"
+	"path/filepath"
 	"runtime"
+	"strings"
 	"sync"
 
 	"github.com/safing/portbase/log"
@@ -50,6 +52,11 @@ func (reg *ResourceRegistry) AddIndex(idx Index) {
 	reg.Lock()
 	defer reg.Unlock()
 
+	// Get channel name from path.
+	idx.Channel = strings.TrimSuffix(
+		filepath.Base(idx.Path), filepath.Ext(idx.Path),
+	)
+
 	reg.indexes = append(reg.indexes, idx)
 }
 

updater/storage.go

@@ -2,7 +2,6 @@ package updater
 
 import (
 	"context"
-	"encoding/json"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -131,18 +130,26 @@ func (reg *ResourceRegistry) loadIndexFile(idx Index) error {
 		return err
 	}
 
-	releases := make(map[string]string)
-	err = json.Unmarshal(data, &releases)
+	// Parse the index file.
+	indexFile, err := ParseIndexFile(data, idx.Channel, idx.LastRelease)
 	if err != nil {
 		return err
 	}
 
-	if len(releases) == 0 {
-		log.Debugf("%s: index %s is empty", reg.Name, idx.Path)
+	// Update last seen release.
+	// TODO: We are working with a copy here, so this has no effect.
+	// This does not break to current implementation, but make the
+	// protection ineffective.
+	idx.LastRelease = indexFile.Published
+
+	// Warn if there aren't any releases in the index.
+	if len(indexFile.Releases) == 0 {
+		log.Debugf("%s: index %s has no releases", reg.Name, idx.Path)
 		return nil
 	}
 
-	err = reg.AddResources(releases, false, true, idx.PreRelease)
+	// Add index releases to available resources.
+	err = reg.AddResources(indexFile.Releases, false, true, idx.PreRelease)
 	if err != nil {
 		log.Warningf("%s: failed to add resource: %s", reg.Name, err)
 	}

updater/updating.go

@@ -2,7 +2,6 @@ package updater
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net/http"
@@ -52,23 +51,22 @@ func (reg *ResourceRegistry) downloadIndex(ctx context.Context, client *http.Cli
 		return fmt.Errorf("failed to download index %s: %w", idx.Path, err)
 	}
 
-	// parse
-	newIndexData := make(map[string]string)
-	err = json.Unmarshal(data, &newIndexData)
+	// Parse the index file.
+	indexFile, err := ParseIndexFile(data, idx.Channel, idx.LastRelease)
 	if err != nil {
 		return fmt.Errorf("failed to parse index %s: %w", idx.Path, err)
 	}
 
 	// Add index data to registry.
-	if len(newIndexData) > 0 {
+	if len(indexFile.Releases) > 0 {
 		// Check if all resources are within the indexes' authority.
 		authoritativePath := path.Dir(idx.Path) + "/"
 		if authoritativePath == "./" {
 			// Fix path for indexes at the storage root.
 			authoritativePath = ""
 		}
-		cleanedData := make(map[string]string, len(newIndexData))
-		for key, version := range newIndexData {
+		cleanedData := make(map[string]string, len(indexFile.Releases))
+		for key, version := range indexFile.Releases {
 			if strings.HasPrefix(key, authoritativePath) {
 				cleanedData[key] = version
 			} else {
@@ -100,7 +98,7 @@ func (reg *ResourceRegistry) downloadIndex(ctx context.Context, client *http.Cli
 		log.Warningf("%s: failed to save updated index %s: %s", reg.Name, idx.Path, err)
 	}
 
-	log.Infof("%s: updated index %s with %d entries", reg.Name, idx.Path, len(newIndexData))
+	log.Infof("%s: updated index %s with %d entries", reg.Name, idx.Path, len(indexFile.Releases))
 	return nil
 }