FABRID detachable extensions

private/path/combinator/fabrid_accumulator.go

@@ -0,0 +1,80 @@
+// Copyright 2018 ETH Zurich, Anapaya Systems
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package combinator
+
+import (
+ "time"
+
+ "github.com/scionproto/scion/pkg/addr"
+ "github.com/scionproto/scion/pkg/experimental/fabrid"
+ fabrid_ext "github.com/scionproto/scion/pkg/segment/extensions/fabrid"
+ "github.com/scionproto/scion/pkg/snet"
+)
+
+// We go through the list of ASEntries and store for each IA a pointer to the FABRID
+// Map found in the ASEntries' extensions. If there is already a map stored, check the info time,
+// and replace with the newer FABRID maps. This results in a map[IA]FabridMapEntry, which can be
+// used to find the policies that are available for each of the interface pairs on the path.
+type FabridMapEntry struct {
+ Map *fabrid_ext.Detached
+ Ts time.Time
+ // The Digest of the Fabrid Maps, this can be empty.
+ Digest []byte
+}
+
+func GetFabridInfoForIntfs(ia addr.IA, ig, eg uint16, maps map[addr.IA]FabridMapEntry,
+ allowIpPolicies bool) *snet.FabridInfo {
+ policies := make([]*fabrid.Policy, 0)
+ fabridMap, exist := maps[ia]
+ if !exist {
+ return &snet.FabridInfo{
+ Enabled: false,
+ Policies: policies,
+ Digest: []byte{},
+ Detached: false,
+ }
+ } else if fabridMap.Map == nil {
+ return &snet.FabridInfo{
+ Enabled: true,
+ Policies: policies,
+ Digest: fabridMap.Digest,
+ Detached: len(fabridMap.Digest) > 0,
+ }
+ }
+ for k, v := range fabridMap.Map.SupportedIndicesMap {
+ if !k.Matches(ig, eg, allowIpPolicies) {
+ continue
+ }
+ for _, policy := range v {
+ val, ok := fabridMap.Map.IndexIdentiferMap[policy]
+ if !ok {
+ continue
+ }
+ policies = append(policies, &fabrid.Policy{
+ IsLocal: val.IsLocal,
+ Identifier: val.Identifier,
+ Index: fabrid.PolicyID(policy),
+ })
+
+ }
+ }
+
+ return &snet.FabridInfo{
+ Enabled: true,
+ Policies: policies,
+ Digest: fabridMap.Digest,
+ Detached: false,
+ }
+}