Remove IAMSys dependency from IAMStorageAPI (#13436)

IAMSys is a higher-level object, that should not be called by the lower-level
storage API interface for IAM. This is to prepare for further improvements in
IAM code.

cmd/iam-dummy-store.go

@@ -81,10 +81,6 @@ func (ids *iamDummyStore) loadMappedPolicies(ctx context.Context, userType IAMUs
 	return nil
 }
 
-func (ids *iamDummyStore) loadAll(ctx context.Context, sys *IAMSys) error {
-	return sys.Load(ctx, ids)
-}
-
 func (ids *iamDummyStore) saveIAMConfig(ctx context.Context, item interface{}, path string, opts ...options) error {
 	return nil
 }
@@ -128,6 +124,3 @@ func (ids *iamDummyStore) deleteUserIdentity(ctx context.Context, name string, u
 func (ids *iamDummyStore) deleteGroupInfo(ctx context.Context, name string) error {
 	return nil
 }
-
-func (ids *iamDummyStore) watch(context.Context, *IAMSys) {
-}

cmd/iam-etcd-store.go

@@ -457,10 +457,6 @@ func (ies *IAMEtcdStore) loadMappedPolicies(ctx context.Context, userType IAMUse
 
 }
 
-func (ies *IAMEtcdStore) loadAll(ctx context.Context, sys *IAMSys) error {
-	return sys.Load(ctx, ies)
-}
-
 func (ies *IAMEtcdStore) savePolicyDoc(ctx context.Context, policyName string, p iampolicy.Policy) error {
 	return ies.saveIAMConfig(ctx, &p, getPolicyDocPath(policyName))
 }
@@ -509,12 +505,16 @@ func (ies *IAMEtcdStore) deleteGroupInfo(ctx context.Context, name string) error
 	return err
 }
 
-func (ies *IAMEtcdStore) watch(ctx context.Context, sys *IAMSys) {
+func (ies *IAMEtcdStore) watch(ctx context.Context, keyPath string) <-chan iamWatchEvent {
+	ch := make(chan iamWatchEvent)
+
+	// go routine to read events from the etcd watch channel and send them
+	// down `ch`
+	go func() {
 		for {
 		outerLoop:
-		// Refresh IAMSys with etcd watch.
 			watchCh := ies.client.Watch(ctx,
-			iamConfigPrefix, etcd.WithPrefix(), etcd.WithKeysOnly())
+				keyPath, etcd.WithPrefix(), etcd.WithKeysOnly())
 
 			for {
 				select {
@@ -536,126 +536,27 @@ func (ies *IAMEtcdStore) watch(ctx context.Context, sys *IAMSys) {
 						goto outerLoop
 					}
 					for _, event := range watchResp.Events {
-					ies.lock()
-					ies.reloadFromEvent(sys, event)
-					ies.unlock()
+						isCreateEvent := event.IsModify() || event.IsCreate()
+						isDeleteEvent := event.Type == etcd.EventTypeDelete
+
+						switch {
+						case isCreateEvent:
+							ch <- iamWatchEvent{
+								isCreated: true,
+								keyPath:   string(event.Kv.Key),
+							}
+						case isDeleteEvent:
+							ch <- iamWatchEvent{
+								isCreated: false,
+								keyPath:   string(event.Kv.Key),
+							}
+						}
+
 					}
 				}
 			}
 		}
-}
-
-// sys.RLock is held by caller.
-func (ies *IAMEtcdStore) reloadFromEvent(sys *IAMSys, event *etcd.Event) {
-	eventCreate := event.IsModify() || event.IsCreate()
-	eventDelete := event.Type == etcd.EventTypeDelete
-	usersPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigUsersPrefix)
-	groupsPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigGroupsPrefix)
-	stsPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigSTSPrefix)
-	svcPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigServiceAccountsPrefix)
-	policyPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigPoliciesPrefix)
-	policyDBUsersPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigPolicyDBUsersPrefix)
-	policyDBSTSUsersPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigPolicyDBSTSUsersPrefix)
-	policyDBGroupsPrefix := strings.HasPrefix(string(event.Kv.Key), iamConfigPolicyDBGroupsPrefix)
-
-	ctx, cancel := context.WithTimeout(context.Background(), defaultContextTimeout)
-	defer cancel()
-
-	switch {
-	case eventCreate:
-		switch {
-		case usersPrefix:
-			accessKey := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigUsersPrefix))
-			ies.loadUser(ctx, accessKey, regUser, sys.iamUsersMap)
-		case stsPrefix:
-			accessKey := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigSTSPrefix))
-			// Not using ies.loadUser due to the custom loading of an STS account
-			var u UserIdentity
-			if err := ies.loadIAMConfig(ctx, &u, getUserIdentityPath(accessKey, stsUser)); err == nil {
-				ies.addUser(ctx, accessKey, stsUser, u, sys.iamUsersMap)
-				// We are on purpose not persisting the policy map for parent
-				// user, although this is a hack, it is a good enough hack
-				// at this point in time - we need to overhaul our OIDC
-				// usage with service accounts with a more cleaner implementation
-				//
-				// This mapping is necessary to ensure that valid credentials
-				// have necessary ParentUser present - this is mainly for only
-				// webIdentity based STS tokens.
-				parentAccessKey := u.Credentials.ParentUser
-				if parentAccessKey != "" && parentAccessKey != globalActiveCred.AccessKey {
-					if _, ok := sys.iamUserPolicyMap[parentAccessKey]; !ok {
-						sys.iamUserPolicyMap[parentAccessKey] = sys.iamUserPolicyMap[accessKey]
-					}
-				}
-			}
-		case svcPrefix:
-			accessKey := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigServiceAccountsPrefix))
-			ies.loadUser(ctx, accessKey, svcUser, sys.iamUsersMap)
-		case groupsPrefix:
-			group := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigGroupsPrefix))
-			ies.loadGroup(ctx, group, sys.iamGroupsMap)
-			gi := sys.iamGroupsMap[group]
-			sys.removeGroupFromMembershipsMap(group)
-			sys.updateGroupMembershipsMap(group, &gi)
-		case policyPrefix:
-			policyName := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPoliciesPrefix))
-			ies.loadPolicyDoc(ctx, policyName, sys.iamPolicyDocsMap)
-		case policyDBUsersPrefix:
-			policyMapFile := strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPolicyDBUsersPrefix)
-			user := strings.TrimSuffix(policyMapFile, ".json")
-			ies.loadMappedPolicy(ctx, user, regUser, false, sys.iamUserPolicyMap)
-		case policyDBSTSUsersPrefix:
-			policyMapFile := strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPolicyDBSTSUsersPrefix)
-			user := strings.TrimSuffix(policyMapFile, ".json")
-			ies.loadMappedPolicy(ctx, user, stsUser, false, sys.iamUserPolicyMap)
-		case policyDBGroupsPrefix:
-			policyMapFile := strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPolicyDBGroupsPrefix)
-			user := strings.TrimSuffix(policyMapFile, ".json")
-			ies.loadMappedPolicy(ctx, user, regUser, true, sys.iamGroupPolicyMap)
-		}
-	case eventDelete:
-		switch {
-		case usersPrefix:
-			accessKey := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigUsersPrefix))
-			delete(sys.iamUsersMap, accessKey)
-		case stsPrefix:
-			accessKey := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigSTSPrefix))
-			delete(sys.iamUsersMap, accessKey)
-		case groupsPrefix:
-			group := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigGroupsPrefix))
-			sys.removeGroupFromMembershipsMap(group)
-			delete(sys.iamGroupsMap, group)
-			delete(sys.iamGroupPolicyMap, group)
-		case policyPrefix:
-			policyName := path.Dir(strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPoliciesPrefix))
-			delete(sys.iamPolicyDocsMap, policyName)
-		case policyDBUsersPrefix:
-			policyMapFile := strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPolicyDBUsersPrefix)
-			user := strings.TrimSuffix(policyMapFile, ".json")
-			delete(sys.iamUserPolicyMap, user)
-		case policyDBSTSUsersPrefix:
-			policyMapFile := strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPolicyDBSTSUsersPrefix)
-			user := strings.TrimSuffix(policyMapFile, ".json")
-			delete(sys.iamUserPolicyMap, user)
-		case policyDBGroupsPrefix:
-			policyMapFile := strings.TrimPrefix(string(event.Kv.Key),
-				iamConfigPolicyDBGroupsPrefix)
-			user := strings.TrimSuffix(policyMapFile, ".json")
-			delete(sys.iamGroupPolicyMap, user)
-		}
-	}
+	}()
+	return ch
+
 }

cmd/iam-object-store.go

@@ -22,7 +22,6 @@ import (
 	"path"
 	"strings"
 	"sync"
-	"time"
 	"unicode/utf8"
 
 	jsoniter "github.com/json-iterator/go"
@@ -370,11 +369,6 @@ func (iamOS *IAMObjectStore) loadMappedPolicies(ctx context.Context, userType IA
 	return nil
 }
 
-// Refresh IAMSys. If an object layer is passed in use that, otherwise load from global.
-func (iamOS *IAMObjectStore) loadAll(ctx context.Context, sys *IAMSys) error {
-	return sys.Load(ctx, iamOS)
-}
-
 func (iamOS *IAMObjectStore) savePolicyDoc(ctx context.Context, policyName string, p iampolicy.Policy) error {
 	return iamOS.saveIAMConfig(ctx, &p, getPolicyDocPath(policyName))
 }
@@ -463,13 +457,3 @@ func listIAMConfigItems(ctx context.Context, objAPI ObjectLayer, pathPrefix stri
 
 	return ch
 }
-
-func (iamOS *IAMObjectStore) watch(ctx context.Context, sys *IAMSys) {
-	// Refresh IAMSys.
-	for {
-		time.Sleep(globalRefreshIAMInterval)
-		if err := iamOS.loadAll(ctx, sys); err != nil {
-			logger.LogIf(ctx, err)
-		}
-	}
-}

cmd/iam.go

@@ -25,6 +25,7 @@ import (
 	"errors"
 	"fmt"
 	"math/rand"
+	"path"
 	"strings"
 	"sync"
 	"time"
@@ -240,6 +241,11 @@ type options struct {
 	ttl int64 //expiry in seconds
 }
 
+type iamWatchEvent struct {
+	isCreated bool // !isCreated implies a delete event.
+	keyPath   string
+}
+
 // IAMStorageAPI defines an interface for the IAM persistence layer
 type IAMStorageAPI interface {
 	lock()
@@ -262,8 +268,6 @@ type IAMStorageAPI interface {
 	loadMappedPolicy(ctx context.Context, name string, userType IAMUserType, isGroup bool, m map[string]MappedPolicy) error
 	loadMappedPolicies(ctx context.Context, userType IAMUserType, isGroup bool, m map[string]MappedPolicy) error
 
-	loadAll(context.Context, *IAMSys) error
-
 	saveIAMConfig(ctx context.Context, item interface{}, path string, opts ...options) error
 	loadIAMConfig(ctx context.Context, item interface{}, path string) error
 	deleteIAMConfig(ctx context.Context, path string) error
@@ -277,8 +281,12 @@ type IAMStorageAPI interface {
 	deleteMappedPolicy(ctx context.Context, name string, userType IAMUserType, isGroup bool) error
 	deleteUserIdentity(ctx context.Context, name string, userType IAMUserType) error
 	deleteGroupInfo(ctx context.Context, name string) error
+}
 
-	watch(context.Context, *IAMSys)
+// iamStorageWatcher is implemented by `IAMStorageAPI` implementers that
+// additionally support watching storage for changes.
+type iamStorageWatcher interface {
+	watch(ctx context.Context, keyPath string) <-chan iamWatchEvent
 }
 
 // LoadGroup - loads a specific group from storage, and updates the
@@ -642,7 +650,7 @@ func (sys *IAMSys) Init(ctx context.Context, objAPI ObjectLayer) {
 	}
 
 	for {
-		if err := sys.store.loadAll(retryCtx, sys); err != nil {
+		if err := sys.Load(retryCtx, sys.store); err != nil {
 			if configRetriableErrors(err) {
 				logger.Info("Waiting for all MinIO IAM sub-system to be initialized.. possible cause (%v)", err)
 				time.Sleep(time.Duration(r.Float64() * float64(5*time.Second)))
@@ -674,7 +682,146 @@ func (sys *IAMSys) Init(ctx context.Context, objAPI ObjectLayer) {
 		}()
 	}
 
-	go sys.store.watch(ctx, sys)
+	go sys.watch(ctx)
+}
+
+func (sys *IAMSys) watch(ctx context.Context) {
+	watcher, ok := sys.store.(iamStorageWatcher)
+	if ok {
+		ch := watcher.watch(ctx, iamConfigPrefix)
+		for event := range ch {
+			// we simply log errors
+			err := sys.loadWatchedEvent(ctx, event)
+			logger.LogIf(ctx, err)
+		}
+
+	} else {
+		// Fall back to loading all items
+		for {
+			time.Sleep(globalRefreshIAMInterval)
+			if err := sys.Load(ctx, sys.store); err != nil {
+				logger.LogIf(ctx, err)
+			}
+		}
+	}
+}
+
+func (sys *IAMSys) loadWatchedEvent(outerCtx context.Context, event iamWatchEvent) (err error) {
+	usersPrefix := strings.HasPrefix(event.keyPath, iamConfigUsersPrefix)
+	groupsPrefix := strings.HasPrefix(event.keyPath, iamConfigGroupsPrefix)
+	stsPrefix := strings.HasPrefix(event.keyPath, iamConfigSTSPrefix)
+	svcPrefix := strings.HasPrefix(event.keyPath, iamConfigServiceAccountsPrefix)
+	policyPrefix := strings.HasPrefix(event.keyPath, iamConfigPoliciesPrefix)
+	policyDBUsersPrefix := strings.HasPrefix(event.keyPath, iamConfigPolicyDBUsersPrefix)
+	policyDBSTSUsersPrefix := strings.HasPrefix(event.keyPath, iamConfigPolicyDBSTSUsersPrefix)
+	policyDBGroupsPrefix := strings.HasPrefix(event.keyPath, iamConfigPolicyDBGroupsPrefix)
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultContextTimeout)
+	defer cancel()
+
+	// We need to read from storage and write to in-memory map, so we need
+	// only a read lock on storage, however in some cases we modify storage
+	// too (e.g. when credentials from storage are expired, we delete them),
+	// so we take write locks for both.
+	sys.Lock()
+	defer sys.Unlock()
+
+	sys.store.lock()
+	defer sys.store.unlock()
+
+	if event.isCreated {
+		switch {
+		case usersPrefix:
+			accessKey := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigUsersPrefix))
+			err = sys.store.loadUser(ctx, accessKey, regUser, sys.iamUsersMap)
+		case stsPrefix:
+			accessKey := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigSTSPrefix))
+			err = sys.store.loadUser(ctx, accessKey, stsUser, sys.iamUsersMap)
+			if err == nil {
+				// We need to update the policy map for the
+				// parent below, so we retrieve the credentials
+				// just added.
+				creds, ok := sys.iamUsersMap[accessKey]
+				if !ok {
+					// This could happen, if the credential
+					// being loaded has expired.
+					break
+				}
+
+				// We are on purpose not persisting the policy map for parent
+				// user, although this is a hack, it is a good enough hack
+				// at this point in time - we need to overhaul our OIDC
+				// usage with service accounts with a more cleaner implementation
+				//
+				// This mapping is necessary to ensure that valid credentials
+				// have necessary ParentUser present - this is mainly for only
+				// webIdentity based STS tokens.
+				parentAccessKey := creds.ParentUser
+				if parentAccessKey != "" && parentAccessKey != globalActiveCred.AccessKey {
+					if _, ok := sys.iamUserPolicyMap[parentAccessKey]; !ok {
+						sys.iamUserPolicyMap[parentAccessKey] = sys.iamUserPolicyMap[accessKey]
+					}
+				}
+			}
+		case svcPrefix:
+			accessKey := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigServiceAccountsPrefix))
+			err = sys.store.loadUser(ctx, accessKey, svcUser, sys.iamUsersMap)
+		case groupsPrefix:
+			group := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigGroupsPrefix))
+			err = sys.store.loadGroup(ctx, group, sys.iamGroupsMap)
+			if err == nil {
+				gi := sys.iamGroupsMap[group]
+				sys.removeGroupFromMembershipsMap(group)
+				sys.updateGroupMembershipsMap(group, &gi)
+			}
+		case policyPrefix:
+			policyName := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigPoliciesPrefix))
+			err = sys.store.loadPolicyDoc(ctx, policyName, sys.iamPolicyDocsMap)
+		case policyDBUsersPrefix:
+			policyMapFile := strings.TrimPrefix(event.keyPath, iamConfigPolicyDBUsersPrefix)
+			user := strings.TrimSuffix(policyMapFile, ".json")
+			err = sys.store.loadMappedPolicy(ctx, user, regUser, false, sys.iamUserPolicyMap)
+		case policyDBSTSUsersPrefix:
+			policyMapFile := strings.TrimPrefix(event.keyPath, iamConfigPolicyDBSTSUsersPrefix)
+			user := strings.TrimSuffix(policyMapFile, ".json")
+			err = sys.store.loadMappedPolicy(ctx, user, stsUser, false, sys.iamUserPolicyMap)
+		case policyDBGroupsPrefix:
+			policyMapFile := strings.TrimPrefix(event.keyPath, iamConfigPolicyDBGroupsPrefix)
+			user := strings.TrimSuffix(policyMapFile, ".json")
+			err = sys.store.loadMappedPolicy(ctx, user, regUser, true, sys.iamGroupPolicyMap)
+		}
+	} else {
+		// delete event
+		switch {
+		case usersPrefix:
+			accessKey := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigUsersPrefix))
+			delete(sys.iamUsersMap, accessKey)
+		case stsPrefix:
+			accessKey := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigSTSPrefix))
+			delete(sys.iamUsersMap, accessKey)
+		case groupsPrefix:
+			group := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigGroupsPrefix))
+			sys.removeGroupFromMembershipsMap(group)
+			delete(sys.iamGroupsMap, group)
+			delete(sys.iamGroupPolicyMap, group)
+		case policyPrefix:
+			policyName := path.Dir(strings.TrimPrefix(event.keyPath, iamConfigPoliciesPrefix))
+			delete(sys.iamPolicyDocsMap, policyName)
+		case policyDBUsersPrefix:
+			policyMapFile := strings.TrimPrefix(event.keyPath, iamConfigPolicyDBUsersPrefix)
+			user := strings.TrimSuffix(policyMapFile, ".json")
+			delete(sys.iamUserPolicyMap, user)
+		case policyDBSTSUsersPrefix:
+			policyMapFile := strings.TrimPrefix(event.keyPath, iamConfigPolicyDBSTSUsersPrefix)
+			user := strings.TrimSuffix(policyMapFile, ".json")
+			delete(sys.iamUserPolicyMap, user)
+		case policyDBGroupsPrefix:
+			policyMapFile := strings.TrimPrefix(event.keyPath, iamConfigPolicyDBGroupsPrefix)
+			user := strings.TrimSuffix(policyMapFile, ".json")
+			delete(sys.iamGroupPolicyMap, user)
+		}
+	}
+	return err
 }
 
 // DeletePolicy - deletes a canned policy from backend or etcd.