package consul import ( "errors" "fmt" "time" "github.com/armon/go-metrics" "github.com/armon/go-metrics/prometheus" "github.com/hashicorp/go-bexpr" "github.com/hashicorp/go-hclog" "github.com/hashicorp/go-memdb" hashstructure_v2 "github.com/mitchellh/hashstructure/v2" "github.com/hashicorp/consul/acl" "github.com/hashicorp/consul/agent/consul/state" "github.com/hashicorp/consul/agent/structs" "github.com/hashicorp/consul/lib" ) var IntentionSummaries = []prometheus.SummaryDefinition{ { Name: []string{"consul", "intention", "apply"}, Help: "", }, { Name: []string{"intention", "apply"}, Help: "", }, } var ( // ErrIntentionNotFound is returned if the intention lookup failed. ErrIntentionNotFound = errors.New("Intention not found") ) // Intention manages the Connect intentions. type Intention struct { // srv is a pointer back to the server. srv *Server logger hclog.Logger } func (s *Intention) checkIntentionID(id string) (bool, error) { state := s.srv.fsm.State() if _, _, ixn, err := state.IntentionGet(nil, id); err != nil { return false, err } else if ixn != nil { return false, nil } return true, nil } var ErrIntentionsNotUpgradedYet = errors.New("Intentions are read only while being upgraded to config entries") // legacyUpgradeCheck fast fails a write request using the legacy intention // RPCs if the system is known to be mid-upgrade. This is purely a perf // optimization and the actual real enforcement happens in the FSM. It would be // wasteful to round trip all the way through raft to have it fail for // known-up-front reasons, hence why we check it twice. func (s *Intention) legacyUpgradeCheck() error { usingConfigEntries, err := s.srv.fsm.State().AreIntentionsInConfigEntries() if err != nil { return fmt.Errorf("system metadata lookup failed: %v", err) } if !usingConfigEntries { return ErrIntentionsNotUpgradedYet } return nil } // Apply creates or updates an intention in the data store. func (s *Intention) Apply(args *structs.IntentionRequest, reply *string) error { // Exit early if Connect hasn't been enabled. if !s.srv.config.ConnectEnabled { return ErrConnectNotEnabled } // Ensure that all service-intentions config entry writes go to the primary // datacenter. These will then be replicated to all the other datacenters. args.Datacenter = s.srv.config.PrimaryDatacenter if done, err := s.srv.ForwardRPC("Intention.Apply", args, reply); done { return err } defer metrics.MeasureSince([]string{"consul", "intention", "apply"}, time.Now()) defer metrics.MeasureSince([]string{"intention", "apply"}, time.Now()) if err := s.legacyUpgradeCheck(); err != nil { return err } if args.Mutation != nil { return fmt.Errorf("Mutation field is internal only and must not be set via RPC") } // Always set a non-nil intention to avoid nil-access below if args.Intention == nil { args.Intention = &structs.Intention{} } // Get the ACL token for the request for the checks below. var entMeta structs.EnterpriseMeta authz, err := s.srv.ACLResolver.ResolveTokenAndDefaultMeta(args.Token, &entMeta, nil) if err != nil { return err } accessorID := authz.AccessorID() var ( mut *structs.IntentionMutation legacyWrite bool ) switch args.Op { case structs.IntentionOpCreate: legacyWrite = true mut, err = s.computeApplyChangesLegacyCreate(accessorID, authz, &entMeta, args) case structs.IntentionOpUpdate: legacyWrite = true mut, err = s.computeApplyChangesLegacyUpdate(accessorID, authz, &entMeta, args) case structs.IntentionOpUpsert: legacyWrite = false mut, err = s.computeApplyChangesUpsert(accessorID, authz, &entMeta, args) case structs.IntentionOpDelete: if args.Intention.ID == "" { legacyWrite = false mut, err = s.computeApplyChangesDelete(accessorID, authz, &entMeta, args) } else { legacyWrite = true mut, err = s.computeApplyChangesLegacyDelete(accessorID, authz, &entMeta, args) } case structs.IntentionOpDeleteAll: // This is an internal operation initiated by the leader and is not // exposed for general RPC use. return fmt.Errorf("Invalid Intention operation: %v", args.Op) default: return fmt.Errorf("Invalid Intention operation: %v", args.Op) } if err != nil { return err } if mut == nil { return nil // short circuit } if legacyWrite { *reply = args.Intention.ID } else { *reply = "" } // Switch to the config entry manipulating flavor: args.Mutation = mut args.Intention = nil _, err = s.srv.raftApply(structs.IntentionRequestType, args) return err } func (s *Intention) computeApplyChangesLegacyCreate( accessorID string, authz acl.Authorizer, entMeta *structs.EnterpriseMeta, args *structs.IntentionRequest, ) (*structs.IntentionMutation, error) { // This variant is just for legacy UUID-based intentions. args.Intention.FillPartitionAndNamespace(entMeta, true) if !args.Intention.CanWrite(authz) { sn := args.Intention.SourceServiceName() dn := args.Intention.DestinationServiceName() // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("Intention creation denied due to ACLs", "source", sn.String(), "destination", dn.String(), "accessorID", accessorID) return nil, acl.ErrPermissionDenied } // If no ID is provided, generate a new ID. This must be done prior to // appending to the Raft log, because the ID is not deterministic. Once // the entry is in the log, the state update MUST be deterministic or // the followers will not converge. if args.Intention.ID != "" { return nil, fmt.Errorf("ID must be empty when creating a new intention") } var err error args.Intention.ID, err = lib.GenerateUUID(s.checkIntentionID) if err != nil { return nil, err } // Set the created at args.Intention.CreatedAt = time.Now().UTC() args.Intention.UpdatedAt = args.Intention.CreatedAt // Default source type if args.Intention.SourceType == "" { args.Intention.SourceType = structs.IntentionSourceConsul } if err := s.validateEnterpriseIntention(args.Intention); err != nil { return nil, err } //nolint:staticcheck if err := args.Intention.Validate(); err != nil { return nil, err } // NOTE: if the append of this source causes a duplicate source name the // config entry validation will fail so we don't have to check that // explicitly here. mut := &structs.IntentionMutation{ Destination: args.Intention.DestinationServiceName(), Value: args.Intention.ToSourceIntention(true), } // Set the created/updated times. If this is an update instead of an insert // the UpdateOver() will fix it up appropriately. now := time.Now().UTC() mut.Value.LegacyCreateTime = timePointer(now) mut.Value.LegacyUpdateTime = timePointer(now) return mut, nil } func (s *Intention) computeApplyChangesLegacyUpdate( accessorID string, authz acl.Authorizer, entMeta *structs.EnterpriseMeta, args *structs.IntentionRequest, ) (*structs.IntentionMutation, error) { // This variant is just for legacy UUID-based intentions. _, _, ixn, err := s.srv.fsm.State().IntentionGet(nil, args.Intention.ID) if err != nil { return nil, fmt.Errorf("Intention lookup failed: %v", err) } if ixn == nil { return nil, fmt.Errorf("Cannot modify non-existent intention: '%s'", args.Intention.ID) } if !ixn.CanWrite(authz) { // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("Update operation on intention denied due to ACLs", "intention", args.Intention.ID, "accessorID", accessorID) return nil, acl.ErrPermissionDenied } args.Intention.FillPartitionAndNamespace(entMeta, true) // Prior to v1.9.0 renames of the destination side of an intention were // allowed, but that behavior doesn't work anymore. if ixn.DestinationServiceName() != args.Intention.DestinationServiceName() { return nil, fmt.Errorf("Cannot modify Destination partition/namespace/name for an intention once it exists.") } // Default source type if args.Intention.SourceType == "" { args.Intention.SourceType = structs.IntentionSourceConsul } if err := s.validateEnterpriseIntention(args.Intention); err != nil { return nil, err } // Validate. We do not validate on delete since it is valid to only // send an ID in that case. //nolint:staticcheck if err := args.Intention.Validate(); err != nil { return nil, err } mut := &structs.IntentionMutation{ ID: args.Intention.ID, Value: args.Intention.ToSourceIntention(true), } // Set the created/updated times. If this is an update instead of an insert // the UpdateOver() will fix it up appropriately. now := time.Now().UTC() mut.Value.LegacyCreateTime = timePointer(now) mut.Value.LegacyUpdateTime = timePointer(now) return mut, nil } func (s *Intention) computeApplyChangesUpsert( accessorID string, authz acl.Authorizer, entMeta *structs.EnterpriseMeta, args *structs.IntentionRequest, ) (*structs.IntentionMutation, error) { // This variant is just for config-entry based intentions. if args.Intention.ID != "" { // This is a new-style only endpoint return nil, fmt.Errorf("ID must not be specified") } args.Intention.FillPartitionAndNamespace(entMeta, true) if !args.Intention.CanWrite(authz) { sn := args.Intention.SourceServiceName() dn := args.Intention.DestinationServiceName() // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("Intention upsert denied due to ACLs", "source", sn.String(), "destination", dn.String(), "accessorID", accessorID) return nil, acl.ErrPermissionDenied } _, prevEntry, err := s.srv.fsm.State().ConfigEntry(nil, structs.ServiceIntentions, args.Intention.DestinationName, args.Intention.DestinationEnterpriseMeta()) if err != nil { return nil, fmt.Errorf("Intention lookup failed: %v", err) } if prevEntry == nil { // Meta is NOT permitted here, as it would need to be persisted on // the enclosing config entry. if len(args.Intention.Meta) > 0 { return nil, fmt.Errorf("Meta must not be specified") } } else { if len(args.Intention.Meta) > 0 { // Meta is NOT permitted here, but there is one exception. If // you are updating a previous record, but that record lives // within a config entry that itself has Meta, then you may // incidentally ship the Meta right back to consul. // // In that case if Meta is provided, it has to be a perfect // match for what is already on the enclosing config entry so // it's safe to discard. if !equalStringMaps(prevEntry.GetMeta(), args.Intention.Meta) { return nil, fmt.Errorf("Meta must not be specified, or should be unchanged during an update.") } // Now it is safe to discard args.Intention.Meta = nil } } return &structs.IntentionMutation{ Destination: args.Intention.DestinationServiceName(), Source: args.Intention.SourceServiceName(), Value: args.Intention.ToSourceIntention(false), }, nil } func (s *Intention) computeApplyChangesLegacyDelete( accessorID string, authz acl.Authorizer, entMeta *structs.EnterpriseMeta, args *structs.IntentionRequest, ) (*structs.IntentionMutation, error) { _, _, ixn, err := s.srv.fsm.State().IntentionGet(nil, args.Intention.ID) if err != nil { return nil, fmt.Errorf("Intention lookup failed: %v", err) } if ixn == nil { return nil, fmt.Errorf("Cannot delete non-existent intention: '%s'", args.Intention.ID) } if !ixn.CanWrite(authz) { // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("Deletion operation on intention denied due to ACLs", "intention", args.Intention.ID, "accessorID", accessorID) return nil, acl.ErrPermissionDenied } return &structs.IntentionMutation{ ID: args.Intention.ID, }, nil } func (s *Intention) computeApplyChangesDelete( accessorID string, authz acl.Authorizer, entMeta *structs.EnterpriseMeta, args *structs.IntentionRequest, ) (*structs.IntentionMutation, error) { args.Intention.FillPartitionAndNamespace(entMeta, true) if !args.Intention.CanWrite(authz) { sn := args.Intention.SourceServiceName() dn := args.Intention.DestinationServiceName() // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("Intention delete denied due to ACLs", "source", sn.String(), "destination", dn.String(), "accessorID", accessorID) return nil, acl.ErrPermissionDenied } // Pre-flight to avoid pointless raft operations. exactIxn := args.Intention.ToExact() _, _, ixn, err := s.srv.fsm.State().IntentionGetExact(nil, exactIxn) if err != nil { return nil, fmt.Errorf("Intention lookup failed: %v", err) } if ixn == nil { return nil, nil // by-name deletions are idempotent } return &structs.IntentionMutation{ Destination: args.Intention.DestinationServiceName(), Source: args.Intention.SourceServiceName(), }, nil } // Get returns a single intention by ID. func (s *Intention) Get(args *structs.IntentionQueryRequest, reply *structs.IndexedIntentions) error { // Exit early if Connect hasn't been enabled. if !s.srv.config.ConnectEnabled { return ErrConnectNotEnabled } // Forward if necessary if done, err := s.srv.ForwardRPC("Intention.Get", args, reply); done { return err } // Get the ACL token for the request for the checks below. var entMeta structs.EnterpriseMeta authz, err := s.srv.ResolveTokenAndDefaultMeta(args.Token, &entMeta, nil) if err != nil { return err } if args.Exact != nil { // // Finish defaulting the namespace fields. if args.Exact.SourceNS == "" { args.Exact.SourceNS = entMeta.NamespaceOrDefault() } if err := s.srv.validateEnterpriseIntentionNamespace(args.Exact.SourceNS, true); err != nil { return fmt.Errorf("Invalid SourceNS %q: %v", args.Exact.SourceNS, err) } if args.Exact.DestinationNS == "" { args.Exact.DestinationNS = entMeta.NamespaceOrDefault() } if err := s.srv.validateEnterpriseIntentionNamespace(args.Exact.DestinationNS, true); err != nil { return fmt.Errorf("Invalid DestinationNS %q: %v", args.Exact.DestinationNS, err) } } return s.srv.blockingQuery( &args.QueryOptions, &reply.QueryMeta, func(ws memdb.WatchSet, state *state.Store) error { var ( index uint64 ixn *structs.Intention err error ) if args.IntentionID != "" { index, _, ixn, err = state.IntentionGet(ws, args.IntentionID) } else if args.Exact != nil { index, _, ixn, err = state.IntentionGetExact(ws, args.Exact) } if err != nil { return err } if ixn == nil { return ErrIntentionNotFound } reply.Index = index reply.Intentions = structs.Intentions{ixn} // Filter s.srv.filterACLWithAuthorizer(authz, reply) // If ACLs prevented any responses, error if len(reply.Intentions) == 0 { accessorID := authz.AccessorID() // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("Request to get intention denied due to ACLs", "intention", args.IntentionID, "accessorID", accessorID) return acl.ErrPermissionDenied } return nil }, ) } // List returns all the intentions. func (s *Intention) List(args *structs.IntentionListRequest, reply *structs.IndexedIntentions) error { // Exit early if Connect hasn't been enabled. if !s.srv.config.ConnectEnabled { return ErrConnectNotEnabled } // Forward if necessary if done, err := s.srv.ForwardRPC("Intention.List", args, reply); done { return err } filter, err := bexpr.CreateFilter(args.Filter, nil, reply.Intentions) if err != nil { return err } var authzContext acl.AuthorizerContext if _, err := s.srv.ResolveTokenAndDefaultMeta(args.Token, &args.EnterpriseMeta, &authzContext); err != nil { return err } if err := s.srv.validateEnterpriseRequest(&args.EnterpriseMeta, false); err != nil { return err } return s.srv.blockingQuery( &args.QueryOptions, &reply.QueryMeta, func(ws memdb.WatchSet, state *state.Store) error { var ( index uint64 ixns structs.Intentions fromConfig bool err error ) if args.Legacy { index, ixns, err = state.LegacyIntentions(ws, &args.EnterpriseMeta) } else { index, ixns, fromConfig, err = state.Intentions(ws, &args.EnterpriseMeta) } if err != nil { return err } reply.Index, reply.Intentions = index, ixns if reply.Intentions == nil { reply.Intentions = make(structs.Intentions, 0) } if fromConfig { reply.DataOrigin = structs.IntentionDataOriginConfigEntries } else { reply.DataOrigin = structs.IntentionDataOriginLegacy } raw, err := filter.Execute(reply.Intentions) if err != nil { return err } reply.Intentions = raw.(structs.Intentions) // Note: we filter the results with ACLs *after* applying the user-supplied // bexpr filter, to ensure QueryMeta.ResultsFilteredByACLs does not include // results that would be filtered out even if the user did have permission. if err := s.srv.filterACL(args.Token, reply); err != nil { return err } return nil }, ) } // Match returns the set of intentions that match the given source/destination. func (s *Intention) Match(args *structs.IntentionQueryRequest, reply *structs.IndexedIntentionMatches) error { // Exit early if Connect hasn't been enabled. if !s.srv.config.ConnectEnabled { return ErrConnectNotEnabled } // Forward if necessary if done, err := s.srv.ForwardRPC("Intention.Match", args, reply); done { return err } // Get the ACL token for the request for the checks below. var entMeta structs.EnterpriseMeta authz, err := s.srv.ResolveTokenAndDefaultMeta(args.Token, &entMeta, nil) if err != nil { return err } // Finish defaulting the namespace and partition fields. for i := range args.Match.Entries { if args.Match.Entries[i].Namespace == "" { args.Match.Entries[i].Namespace = entMeta.NamespaceOrDefault() } if err := s.srv.validateEnterpriseIntentionNamespace(args.Match.Entries[i].Namespace, true); err != nil { return fmt.Errorf("Invalid match entry namespace %q: %v", args.Match.Entries[i].Namespace, err) } if args.Match.Entries[i].Partition == "" { args.Match.Entries[i].Partition = entMeta.PartitionOrDefault() } if err := s.srv.validateEnterpriseIntentionPartition(args.Match.Entries[i].Partition); err != nil { return fmt.Errorf("Invalid match entry partition %q: %v", args.Match.Entries[i].Partition, err) } } var authzContext acl.AuthorizerContext // Go through each entry to ensure we have intentions:read for the resource. // TODO - should we do this instead of filtering the result set? This will only allow // queries for which the token has intentions:read permissions on the requested side // of the service. Should it instead return all matches that it would be able to list. // if so we should remove this and call filterACL instead. Based on how this is used // its probably fine. If you have intention read on the source just do a source type // matching, if you have it on the dest then perform a dest type match. for _, entry := range args.Match.Entries { entry.FillAuthzContext(&authzContext) if prefix := entry.Name; prefix != "" && authz.IntentionRead(prefix, &authzContext) != acl.Allow { accessorID := authz.AccessorID() // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("Operation on intention prefix denied due to ACLs", "prefix", prefix, "accessorID", accessorID) return acl.ErrPermissionDenied } } var ( priorHash uint64 ranOnce bool ) return s.srv.blockingQuery( &args.QueryOptions, &reply.QueryMeta, func(ws memdb.WatchSet, state *state.Store) error { index, matches, err := state.IntentionMatch(ws, args.Match) if err != nil { return err } reply.Index = index reply.Matches = matches // Generate a hash of the intentions content driving this response. // Use it to determine if the response is identical to a prior // wakeup. newHash, err := hashstructure_v2.Hash(matches, hashstructure_v2.FormatV2, nil) if err != nil { return fmt.Errorf("error hashing reply for spurious wakeup suppression: %w", err) } if ranOnce && priorHash == newHash { priorHash = newHash return errNotChanged } else { priorHash = newHash ranOnce = true } hasData := false for _, match := range matches { if len(match) > 0 { hasData = true break } } if !hasData { return errNotFound } return nil }, ) } // Check tests a source/destination and returns whether it would be allowed // or denied based on the current ACL configuration. // // NOTE: This endpoint treats any L7 intentions as DENY. // // Note: Whenever the logic for this method is changed, you should take // a look at the agent authorize endpoint (agent/agent_endpoint.go) since // the logic there is similar. func (s *Intention) Check(args *structs.IntentionQueryRequest, reply *structs.IntentionQueryCheckResponse) error { // Exit early if Connect hasn't been enabled. if !s.srv.config.ConnectEnabled { return ErrConnectNotEnabled } // Forward maybe if done, err := s.srv.ForwardRPC("Intention.Check", args, reply); done { return err } // Get the test args, and defensively guard against nil query := args.Check if query == nil { return errors.New("Check must be specified on args") } // Get the ACL token for the request for the checks below. var entMeta structs.EnterpriseMeta authz, err := s.srv.ResolveTokenAndDefaultMeta(args.Token, &entMeta, nil) if err != nil { return err } // Finish defaulting the namespace fields. if query.SourceNS == "" { query.SourceNS = entMeta.NamespaceOrDefault() } if query.DestinationNS == "" { query.DestinationNS = entMeta.NamespaceOrDefault() } if query.SourcePartition == "" { query.SourcePartition = entMeta.PartitionOrDefault() } if query.DestinationPartition == "" { query.DestinationPartition = entMeta.PartitionOrDefault() } if err := s.srv.validateEnterpriseIntentionNamespace(query.SourceNS, false); err != nil { return fmt.Errorf("Invalid source namespace %q: %v", query.SourceNS, err) } if err := s.srv.validateEnterpriseIntentionNamespace(query.DestinationNS, false); err != nil { return fmt.Errorf("Invalid destination namespace %q: %v", query.DestinationNS, err) } if query.SourceType != structs.IntentionSourceConsul { return fmt.Errorf("unsupported SourceType: %q", query.SourceType) } // Perform the ACL check. For Check we only require ServiceRead and // NOT IntentionRead because the Check API only returns pass/fail and // returns no other information about the intentions used. We could check // both the source and dest side but only checking dest also has the nice // benefit of only returning a passing status if the token would be able // to discover the dest service and connect to it. if prefix, ok := query.GetACLPrefix(); ok { var authzContext acl.AuthorizerContext query.FillAuthzContext(&authzContext) if authz.ServiceRead(prefix, &authzContext) != acl.Allow { accessorID := authz.AccessorID() // todo(kit) Migrate intention access denial logging over to audit logging when we implement it s.logger.Warn("test on intention denied due to ACLs", "prefix", prefix, "accessorID", accessorID) return acl.ErrPermissionDenied } } // Note: the default intention policy is like an intention with a // wildcarded destination in that it is limited to L4-only. // No match, we need to determine the default behavior. We do this by // fetching the default intention behavior from the resolved authorizer. // The default behavior if ACLs are disabled is to allow connections // to mimic the behavior of Consul itself: everything is allowed if // ACLs are disabled. // // NOTE(mitchellh): This is the same behavior as the agent authorize // endpoint. If this behavior is incorrect, we should also change it there // which is much more important. defaultDecision := authz.IntentionDefaultAllow(nil) store := s.srv.fsm.State() entry := structs.IntentionMatchEntry{ Namespace: query.SourceNS, Partition: query.SourcePartition, Name: query.SourceName, } _, intentions, err := store.IntentionMatchOne(nil, entry, structs.IntentionMatchSource) if err != nil { return fmt.Errorf("failed to query intentions for %s/%s", query.SourceNS, query.SourceName) } opts := state.IntentionDecisionOpts{ Target: query.DestinationName, Namespace: query.DestinationNS, Partition: query.DestinationPartition, Intentions: intentions, MatchType: structs.IntentionMatchDestination, DefaultDecision: defaultDecision, AllowPermissions: false, } decision, err := store.IntentionDecision(opts) if err != nil { return fmt.Errorf("failed to get intention decision from (%s/%s) to (%s/%s): %v", query.SourceNS, query.SourceName, query.DestinationNS, query.DestinationName, err) } reply.Allowed = decision.Allowed return nil } func (s *Intention) validateEnterpriseIntention(ixn *structs.Intention) error { if err := s.srv.validateEnterpriseIntentionPartition(ixn.SourcePartition); err != nil { return fmt.Errorf("Invalid source partition %q: %v", ixn.SourcePartition, err) } if err := s.srv.validateEnterpriseIntentionNamespace(ixn.SourceNS, true); err != nil { return fmt.Errorf("Invalid source namespace %q: %v", ixn.SourceNS, err) } if err := s.srv.validateEnterpriseIntentionPartition(ixn.DestinationPartition); err != nil { return fmt.Errorf("Invalid destination partition %q: %v", ixn.DestinationPartition, err) } if err := s.srv.validateEnterpriseIntentionNamespace(ixn.DestinationNS, true); err != nil { return fmt.Errorf("Invalid destination namespace %q: %v", ixn.DestinationNS, err) } return nil } func equalStringMaps(a, b map[string]string) bool { if len(a) != len(b) { return false } for k := range a { v, ok := b[k] if !ok || a[k] != v { return false } } return true }