Files
kubesphere/vendor/github.com/open-policy-agent/opa/bundle/store.go
hongming 9769357005 update
Signed-off-by: hongming <talonwan@yunify.com>
2020-03-20 02:16:11 +08:00

527 lines
15 KiB
Go

// Copyright 2019 The OPA Authors. All rights reserved.
// Use of this source code is governed by an Apache2
// license that can be found in the LICENSE file.
package bundle
import (
"context"
"fmt"
"strings"
"github.com/open-policy-agent/opa/metrics"
"github.com/open-policy-agent/opa/ast"
"github.com/open-policy-agent/opa/storage"
"github.com/open-policy-agent/opa/util"
)
var bundlesBasePath = storage.MustParsePath("/system/bundles")
// Note: As needed these helpers could be memoized.
// ManifestStoragePath is the storage path used for the given named bundle manifest.
func ManifestStoragePath(name string) storage.Path {
return append(bundlesBasePath, name, "manifest")
}
func namedBundlePath(name string) storage.Path {
return append(bundlesBasePath, name)
}
func rootsPath(name string) storage.Path {
return append(bundlesBasePath, name, "manifest", "roots")
}
func revisionPath(name string) storage.Path {
return append(bundlesBasePath, name, "manifest", "revision")
}
// ReadBundleNamesFromStore will return a list of bundle names which have had their metadata stored.
func ReadBundleNamesFromStore(ctx context.Context, store storage.Store, txn storage.Transaction) ([]string, error) {
value, err := store.Read(ctx, txn, bundlesBasePath)
if err != nil {
return nil, err
}
bundleMap, ok := value.(map[string]interface{})
if !ok {
return nil, fmt.Errorf("corrupt manifest roots")
}
bundles := make([]string, len(bundleMap))
idx := 0
for name := range bundleMap {
bundles[idx] = name
idx++
}
return bundles, nil
}
// WriteManifestToStore will write the manifest into the storage. This function is called when
// the bundle is activated.
func WriteManifestToStore(ctx context.Context, store storage.Store, txn storage.Transaction, name string, manifest Manifest) error {
return write(ctx, store, txn, ManifestStoragePath(name), manifest)
}
func write(ctx context.Context, store storage.Store, txn storage.Transaction, path storage.Path, manifest Manifest) error {
var value interface{} = manifest
if err := util.RoundTrip(&value); err != nil {
return err
}
var dir []string
if len(path) > 1 {
dir = path[:len(path)-1]
}
if err := storage.MakeDir(ctx, store, txn, dir); err != nil {
return err
}
return store.Write(ctx, txn, storage.AddOp, path, value)
}
// EraseManifestFromStore will remove the manifest from storage. This function is called
// when the bundle is deactivated.
func EraseManifestFromStore(ctx context.Context, store storage.Store, txn storage.Transaction, name string) error {
path := namedBundlePath(name)
err := store.Write(ctx, txn, storage.RemoveOp, path, nil)
if err != nil && !storage.IsNotFound(err) {
return err
}
return nil
}
// ReadBundleRootsFromStore returns the roots in the specified bundle.
// If the bundle is not activated, this function will return
// storage NotFound error.
func ReadBundleRootsFromStore(ctx context.Context, store storage.Store, txn storage.Transaction, name string) ([]string, error) {
value, err := store.Read(ctx, txn, rootsPath(name))
if err != nil {
return nil, err
}
sl, ok := value.([]interface{})
if !ok {
return nil, fmt.Errorf("corrupt manifest roots")
}
roots := make([]string, len(sl))
for i := range sl {
roots[i], ok = sl[i].(string)
if !ok {
return nil, fmt.Errorf("corrupt manifest root")
}
}
return roots, nil
}
// ReadBundleRevisionFromStore returns the revision in the specified bundle.
// If the bundle is not activated, this function will return
// storage NotFound error.
func ReadBundleRevisionFromStore(ctx context.Context, store storage.Store, txn storage.Transaction, name string) (string, error) {
return readRevisionFromStore(ctx, store, txn, revisionPath(name))
}
func readRevisionFromStore(ctx context.Context, store storage.Store, txn storage.Transaction, path storage.Path) (string, error) {
value, err := store.Read(ctx, txn, path)
if err != nil {
return "", err
}
str, ok := value.(string)
if !ok {
return "", fmt.Errorf("corrupt manifest revision")
}
return str, nil
}
// ActivateOpts defines options for the Activate API call.
type ActivateOpts struct {
Ctx context.Context
Store storage.Store
Txn storage.Transaction
Compiler *ast.Compiler
Metrics metrics.Metrics
Bundles map[string]*Bundle // Optional
ExtraModules map[string]*ast.Module // Optional
legacy bool
}
// Activate the bundle(s) by loading into the given Store. This will load policies, data, and record
// the manifest in storage. The compiler provided will have had the polices compiled on it.
func Activate(opts *ActivateOpts) error {
opts.legacy = false
return activateBundles(opts)
}
// DeactivateOpts defines options for the Deactivate API call
type DeactivateOpts struct {
Ctx context.Context
Store storage.Store
Txn storage.Transaction
BundleNames map[string]struct{}
}
// Deactivate the bundle(s). This will erase associated data, policies, and the manifest entry from the store.
func Deactivate(opts *DeactivateOpts) error {
erase := map[string]struct{}{}
for name := range opts.BundleNames {
if roots, err := ReadBundleRootsFromStore(opts.Ctx, opts.Store, opts.Txn, name); err == nil {
for _, root := range roots {
erase[root] = struct{}{}
}
} else if !storage.IsNotFound(err) {
return err
}
}
_, err := eraseBundles(opts.Ctx, opts.Store, opts.Txn, opts.BundleNames, erase)
return err
}
func activateBundles(opts *ActivateOpts) error {
// Build collections of bundle names, modules, and roots to erase
erase := map[string]struct{}{}
names := map[string]struct{}{}
for name, b := range opts.Bundles {
names[name] = struct{}{}
if roots, err := ReadBundleRootsFromStore(opts.Ctx, opts.Store, opts.Txn, name); err == nil {
for _, root := range roots {
erase[root] = struct{}{}
}
} else if !storage.IsNotFound(err) {
return err
}
// Erase data at new roots to prepare for writing the new data
for _, root := range *b.Manifest.Roots {
erase[root] = struct{}{}
}
}
// Before changing anything make sure the roots don't collide with any
// other bundles that already are activated or other bundles being activated.
err := hasRootsOverlap(opts.Ctx, opts.Store, opts.Txn, opts.Bundles)
if err != nil {
return err
}
// Erase data and policies at new + old roots, and remove the old
// manifests before activating a new bundles.
remaining, err := eraseBundles(opts.Ctx, opts.Store, opts.Txn, names, erase)
if err != nil {
return err
}
for _, b := range opts.Bundles {
// Write data from each new bundle into the store. Only write under the
// roots contained in their manifest. This should be done *before* the
// policies so that path conflict checks can occur.
if err := writeData(opts.Ctx, opts.Store, opts.Txn, *b.Manifest.Roots, b.Data); err != nil {
return err
}
}
// Write and compile the modules all at once to avoid having to re-do work.
remainingAndExtra := make(map[string]*ast.Module)
for name, mod := range remaining {
remainingAndExtra[name] = mod
}
for name, mod := range opts.ExtraModules {
remainingAndExtra[name] = mod
}
err = writeModules(opts.Ctx, opts.Store, opts.Txn, opts.Compiler, opts.Metrics, opts.Bundles, remainingAndExtra, opts.legacy)
if err != nil {
return err
}
for name, b := range opts.Bundles {
// Always write manifests to the named location. If the plugin is in the older style config
// then also write to the old legacy unnamed location.
if err := WriteManifestToStore(opts.Ctx, opts.Store, opts.Txn, name, b.Manifest); err != nil {
return err
}
if opts.legacy {
if err := LegacyWriteManifestToStore(opts.Ctx, opts.Store, opts.Txn, b.Manifest); err != nil {
return err
}
}
}
return nil
}
// erase bundles by name and roots. This will clear all policies and data at its roots and remove its
// manifest from storage.
func eraseBundles(ctx context.Context, store storage.Store, txn storage.Transaction, names map[string]struct{}, roots map[string]struct{}) (map[string]*ast.Module, error) {
if err := eraseData(ctx, store, txn, roots); err != nil {
return nil, err
}
remaining, err := erasePolicies(ctx, store, txn, roots)
if err != nil {
return nil, err
}
for name := range names {
if err := EraseManifestFromStore(ctx, store, txn, name); err != nil && !storage.IsNotFound(err) {
return nil, err
}
if err := LegacyEraseManifestFromStore(ctx, store, txn); err != nil && !storage.IsNotFound(err) {
return nil, err
}
}
return remaining, nil
}
func eraseData(ctx context.Context, store storage.Store, txn storage.Transaction, roots map[string]struct{}) error {
for root := range roots {
path, ok := storage.ParsePathEscaped("/" + root)
if !ok {
return fmt.Errorf("manifest root path invalid: %v", root)
}
if len(path) > 0 {
if err := store.Write(ctx, txn, storage.RemoveOp, path, nil); err != nil {
if !storage.IsNotFound(err) {
return err
}
}
}
}
return nil
}
func erasePolicies(ctx context.Context, store storage.Store, txn storage.Transaction, roots map[string]struct{}) (map[string]*ast.Module, error) {
ids, err := store.ListPolicies(ctx, txn)
if err != nil {
return nil, err
}
remaining := map[string]*ast.Module{}
for _, id := range ids {
bs, err := store.GetPolicy(ctx, txn, id)
if err != nil {
return nil, err
}
module, err := ast.ParseModule(id, string(bs))
if err != nil {
return nil, err
}
path, err := module.Package.Path.Ptr()
if err != nil {
return nil, err
}
deleted := false
for root := range roots {
if strings.HasPrefix(path, root) {
if err := store.DeletePolicy(ctx, txn, id); err != nil {
return nil, err
}
deleted = true
break
}
}
if !deleted {
remaining[id] = module
}
}
return remaining, nil
}
func writeData(ctx context.Context, store storage.Store, txn storage.Transaction, roots []string, data map[string]interface{}) error {
for _, root := range roots {
path, ok := storage.ParsePathEscaped("/" + root)
if !ok {
return fmt.Errorf("manifest root path invalid: %v", root)
}
if value, ok := lookup(path, data); ok {
if len(path) > 0 {
if err := storage.MakeDir(ctx, store, txn, path[:len(path)-1]); err != nil {
return err
}
}
if err := store.Write(ctx, txn, storage.AddOp, path, value); err != nil {
return err
}
}
}
return nil
}
func writeModules(ctx context.Context, store storage.Store, txn storage.Transaction, compiler *ast.Compiler, m metrics.Metrics, bundles map[string]*Bundle, extraModules map[string]*ast.Module, legacy bool) error {
m.Timer(metrics.RegoModuleCompile).Start()
defer m.Timer(metrics.RegoModuleCompile).Stop()
modules := map[string]*ast.Module{}
// preserve any modules already on the compiler
for name, module := range compiler.Modules {
modules[name] = module
}
// preserve any modules passed in from the store
for name, module := range extraModules {
modules[name] = module
}
// include all the new bundle modules
for bundleName, b := range bundles {
if legacy {
for _, mf := range b.Modules {
modules[mf.Path] = mf.Parsed
}
} else {
for name, module := range b.ParsedModules(bundleName) {
modules[name] = module
}
}
}
if compiler.Compile(modules); compiler.Failed() {
return compiler.Errors
}
for bundleName, b := range bundles {
for _, mf := range b.Modules {
var path string
// For backwards compatibility, in legacy mode, upsert policies to
// the unprefixed path.
if legacy {
path = mf.Path
} else {
path = modulePathWithPrefix(bundleName, mf.Path)
}
if err := store.UpsertPolicy(ctx, txn, path, mf.Raw); err != nil {
return err
}
}
}
return nil
}
func lookup(path storage.Path, data map[string]interface{}) (interface{}, bool) {
if len(path) == 0 {
return data, true
}
for i := 0; i < len(path)-1; i++ {
value, ok := data[path[i]]
if !ok {
return nil, false
}
obj, ok := value.(map[string]interface{})
if !ok {
return nil, false
}
data = obj
}
value, ok := data[path[len(path)-1]]
return value, ok
}
func hasRootsOverlap(ctx context.Context, store storage.Store, txn storage.Transaction, bundles map[string]*Bundle) error {
collisions := map[string][]string{}
allBundles, err := ReadBundleNamesFromStore(ctx, store, txn)
if err != nil && !storage.IsNotFound(err) {
return err
}
allRoots := map[string][]string{}
// Build a map of roots for existing bundles already in the system
for _, name := range allBundles {
roots, err := ReadBundleRootsFromStore(ctx, store, txn, name)
if err != nil && !storage.IsNotFound(err) {
return err
}
allRoots[name] = roots
}
// Add in any bundles that are being activated, overwrite existing roots
// with new ones where bundles are in both groups.
for name, bundle := range bundles {
allRoots[name] = *bundle.Manifest.Roots
}
// Now check for each new bundle if it conflicts with any of the others
for name, bundle := range bundles {
for otherBundle, otherRoots := range allRoots {
if name == otherBundle {
// Skip the current bundle being checked
continue
}
// Compare the "new" roots with other existing (or a different bundles new roots)
for _, newRoot := range *bundle.Manifest.Roots {
for _, otherRoot := range otherRoots {
if RootPathsOverlap(newRoot, otherRoot) {
collisions[otherBundle] = append(collisions[otherBundle], newRoot)
}
}
}
}
}
if len(collisions) > 0 {
var bundleNames []string
for name := range collisions {
bundleNames = append(bundleNames, name)
}
return fmt.Errorf("detected overlapping roots in bundle manifest with: %s", bundleNames)
}
return nil
}
// Helpers for the older single (unnamed) bundle style manifest storage.
// LegacyManifestStoragePath is the older unnamed bundle path for manifests to be stored.
// Deprecated: Use ManifestStoragePath and named bundles instead.
var legacyManifestStoragePath = storage.MustParsePath("/system/bundle/manifest")
var legacyRevisionStoragePath = append(legacyManifestStoragePath, "revision")
// LegacyWriteManifestToStore will write the bundle manifest to the older single (unnamed) bundle manifest location.
// Deprecated: Use WriteManifestToStore and named bundles instead.
func LegacyWriteManifestToStore(ctx context.Context, store storage.Store, txn storage.Transaction, manifest Manifest) error {
return write(ctx, store, txn, legacyManifestStoragePath, manifest)
}
// LegacyEraseManifestFromStore will erase the bundle manifest from the older single (unnamed) bundle manifest location.
// Deprecated: Use WriteManifestToStore and named bundles instead.
func LegacyEraseManifestFromStore(ctx context.Context, store storage.Store, txn storage.Transaction) error {
err := store.Write(ctx, txn, storage.RemoveOp, legacyManifestStoragePath, nil)
if err != nil {
return err
}
return nil
}
// LegacyReadRevisionFromStore will read the bundle manifest revision from the older single (unnamed) bundle manifest location.
// Deprecated: Use ReadBundleRevisionFromStore and named bundles instead.
func LegacyReadRevisionFromStore(ctx context.Context, store storage.Store, txn storage.Transaction) (string, error) {
return readRevisionFromStore(ctx, store, txn, legacyRevisionStoragePath)
}
// ActivateLegacy calls Activate for the bundles but will also write their manifest to the older unnamed store location.
// Deprecated: Use Activate with named bundles instead.
func ActivateLegacy(opts *ActivateOpts) error {
opts.legacy = true
return activateBundles(opts)
}