Merge pull request #150 from natesales/prefix-communities

Add `prefix-communities` and `only-announce` options

Author: natesales

cmd/root.go

@@ -7,7 +7,7 @@ import (
 	"github.com/natesales/pathvector/pkg/plugin"
 )
 
-// Build process flags
+// These are set indirectly by the build process. The cmd.Execute() function takes these from the main package and sets them in this (cmd) package.
 var (
 	version = "devel"
 	commit  = "unknown"
@@ -56,7 +56,7 @@ func init() {
 	}
 }
 
-func Execute(v string, c string, d string) error {
+func Execute(v, c, d string) error {
 	version = v
 	commit = c
 	date = d

pkg/config/config.go

@@ -97,6 +97,10 @@ type Peer struct {
 	DontAnnounce *[]string `yaml:"dont-announce" description:"Don't announce these prefixes to the peer" default:"-"`
 	OnlyAnnounce *[]string `yaml:"only-announce" description:"Only announce these prefixes to the peer" default:"-"`
 
+	PrefixCommunities         *map[string][]string `yaml:"prefix-communities" description:"Map of prefix to community list to add to the prefix" default:"-"`
+	PrefixStandardCommunities *map[string][]string `yaml:"-" description:"-" default:"-"`
+	PrefixLargeCommunities    *map[string][]string `yaml:"-" description:"-" default:"-"`
+
 	AutoImportLimits *bool `yaml:"auto-import-limits" description:"Get import limits automatically from PeeringDB?" default:"false"`
 	AutoASSet        *bool `yaml:"auto-as-set" description:"Get as-set automatically from PeeringDB? If no as-set exists in PeeringDB, a warning will be shown and the peer ASN used instead." default:"false"`
 	AutoASSetMembers *bool `yaml:"auto-as-set-members" description:"Get AS set members automatically from the peer's IRR as-set? (independent from auto-as-set)" default:"false"`

pkg/embed/templates/peer.tmpl

@@ -168,6 +168,22 @@ protocol bgp {{ UniqueProtocolName $peer.ProtocolName $af $peer.ASN }} {
             ]) then _reject("prefix in dont-announce list");
             {{ end }}
 
+            {{ range $prefix, $communities := StrSliceMapDeref $peer.PrefixStandardCommunities }}
+            if (net = {{ $prefix }}) then {
+                {{ range $i, $community := $communities }}
+                bgp_community.add(({{ $community }}));
+                {{ end }}
+            }
+            {{ end }}
+
+            {{ range $prefix, $communities := StrSliceMapDeref $peer.PrefixLargeCommunities }}
+            if (net = {{ $prefix }}) then {
+                {{ range $i, $community := $communities }}
+                bgp_large_community.add(({{ $community }}));
+                {{ end }}
+            }
+            {{ end }}
+
             {{ StrDeref $peer.PreExport }}
 
             {{ range $i, $community := StringSliceIter $peer.ExportStandardCommunities }}

pkg/process/process.go

@@ -256,7 +256,37 @@ func Load(configBlob []byte) (*config.Config, error) {
 		if peerData.OnlyAnnounce != nil && peerData.AnnounceAll != nil {
 			log.Fatalf("[%s] only-announce and announce-all cannot both be set", peerName)
 		}
-	}
+
+		// Categorize prefix-communities
+		if peerData.PrefixCommunities != nil {
+			// Initialize community maps
+			if peerData.PrefixStandardCommunities == nil {
+				peerData.PrefixStandardCommunities = &map[string][]string{}
+			}
+			if peerData.PrefixLargeCommunities == nil {
+				peerData.PrefixLargeCommunities = &map[string][]string{}
+			}
+
+			for prefix, communities := range *peerData.PrefixCommunities {
+				for _, community := range communities {
+					communityType := categorizeCommunity(community)
+					if communityType == "standard" {
+						if _, ok := (*peerData.PrefixStandardCommunities)[prefix]; !ok {
+							(*peerData.PrefixStandardCommunities)[prefix] = []string{}
+						}
+						(*peerData.PrefixStandardCommunities)[prefix] = append((*peerData.PrefixStandardCommunities)[prefix], community)
+					} else if communityType == "large" {
+						if _, ok := (*peerData.PrefixLargeCommunities)[prefix]; !ok {
+							(*peerData.PrefixLargeCommunities)[prefix] = []string{}
+						}
+						(*peerData.PrefixLargeCommunities)[prefix] = append((*peerData.PrefixLargeCommunities)[prefix], strings.ReplaceAll(community, ":", ","))
+					} else {
+						return nil, errors.New("Invalid prefix community: " + community)
+					}
+				}
+			}
+		}
+	} // end peer list
 
 	// Parse origin routes by assembling OriginIPv{4,6} lists by address family
 	for _, prefix := range c.Prefixes {

pkg/templating/templating.go

@@ -144,6 +144,13 @@ var funcMap = template.FuncMap{
 		return map[uint32]uint32{}
 	},
 
+	"StrSliceMapDeref": func(m *map[string][]string) map[string][]string {
+		if m != nil {
+			return *m
+		}
+		return map[string][]string{}
+	},
+
 	"Uint32SliceMapDeref": func(m *map[uint32][]uint32) map[uint32][]uint32 {
 		if m != nil {
 			return *m

tests/generate-complex.yml

@@ -86,6 +86,13 @@ peers:
       - 65540
     filter-as-set: true
     pre-import-accept: 'print "Hello from <pathvector.asn>";'
+    prefix-communities:
+      "192.0.2.0/24":
+        - "123,456"
+        - "123,000"
+        - "1:2:3"
+    dont-announce:
+      - 192.0.2.100/32
     transit-lock:
       - 65510
       - 65530