policy: support the match of consecutive AsPath and regular expressions to AsPath Condition

3 files changed, 231 insertions, 44 deletions

diff --git a/docs/sources/filter-detail.md b/docs/sources/filter-detail.md
index b096ed27..f6147547 100644
--- a/docs/sources/filter-detail.md
+++ b/docs/sources/filter-detail.md
@@ -340,6 +340,11 @@ CommunitySets, ExtCommunitySets and AsPathSets section are each match part.
    - Origin: "65100$" means the route is originated by AS 65100.
    - Only: "^65100$" means the route is originated by AS 65100 and comes from it directly.
 
+   Further you can specify the consecutive aspath and use regexp in each element as follows:
+   - ^65100_65001
+   - 65100_[0-9]+_.*$
+   - ^6[0-9]_5.*_65.?00$
+
   ##### Examples
   - example 1
       - Match routes which come from AS 65100.
@@ -354,6 +359,19 @@ CommunitySets, ExtCommunitySets and AsPathSets section are each match part.
           AsPath = "^65100"
   ```
 
+  - example 2
+      - Match routes which come Origin AS 65100 and use regular expressions to other AS.
+
+  ```
+  # example 2
+  [DefinedSets.BgpDefinedSets]
+    [DefinedSets.BgpDefinedSets.AsPathSets]
+      [[DefinedSets.BgpDefinedSets.AsPathSets.AsPathSetList]]
+        AsPathSetName = "aspath2"
+        [[DefinedSets.BgpDefinedSets.AsPathSets.AsPathSetList.AsPathList]]
+          AsPath = "[0-9]+_65[0-9]+_65100$"
+  ```
+
 ---
 
 ### 3. Defining PolicyDefinitions
diff --git a/policy/policy.go b/policy/policy.go
index 0ea3d373..70d1bbc3 100644
--- a/policy/policy.go
+++ b/policy/policy.go
@@ -397,8 +397,9 @@ const (
 )
 
 type AsPathElement struct {
-	postiion AsnPos
-	asn      uint32
+	postiion  AsnPos
+	asStr     string
+	asRegExps []*regexp.Regexp
 }
 
 // create AsPathCondition object
@@ -412,48 +413,69 @@ func NewAsPathCondition(matchSet config.MatchAsPathSet, defAsPathSetList []confi
 	asPathSetName := matchSet.AsPathSet
 	options := matchSet.MatchSetOptions
 
-	regAsn, _ := regexp.Compile("^(\\^?)([0-9]+)(\\$?)$")
 	asPathList := make([]*AsPathElement, 0)
 	for _, asPathSet := range defAsPathSetList {
 		if asPathSet.AsPathSetName == asPathSetName {
 			for _, aspath := range asPathSet.AsPathList {
 				a := aspath.AsPath
-				if regAsn.MatchString(a) {
-
-					group := regAsn.FindStringSubmatch(a)
-					asn, err := strconv.Atoi(group[2])
-					if err != nil {
-						log.WithFields(log.Fields{
-							"Topic": "Policy",
-							"Type":  "AsPath Condition",
-						}).Error("cannot parse AS Number.")
-						return nil
+				if len(a) != 0 {
+					isTop := a[:1] == "^"
+					if isTop {
+						a = a[1:]
+					}
+					isEnd := a[len(a)-1:] == "$"
+					if isEnd {
+						a = a[:len(a)-1]
+					}
+					elems := strings.Split(a, "_")
+					asRegExps := make([]*regexp.Regexp, 0)
+					for _, el := range elems {
+						if len(el) == 0 {
+							log.WithFields(log.Fields{
+								"Topic": "Policy",
+								"Type":  "AsPath Condition",
+								"Value": aspath.AsPath,
+								"Elem":  el,
+							}).Error("invalid element. do not enter a blank.")
+							return nil
+						}
+						regElem, err := regexp.Compile(el)
+						if err != nil {
+							log.WithFields(log.Fields{
+								"Topic": "Policy",
+								"Type":  "AsPath Condition",
+								"Value": aspath.AsPath,
+								"Elem":  el,
+								"Error": err,
+							}).Error("can not comple AS_PATH values to Regular expressions.")
+							return nil
+						}
+						asRegExps = append(asRegExps, regElem)
 					}
-					e := &AsPathElement{}
-					e.asn = uint32(asn)
 
-					if len(group[1]) == 0 && len(group[3]) == 0 {
-						e.postiion = AS_ANY
-					} else if len(group[1]) == 1 && len(group[3]) == 0 {
+					e := &AsPathElement{}
+					e.asRegExps = asRegExps
+					e.asStr = a
+					if isTop && isEnd {
+						e.postiion = AS_ONLY
+					} else if isTop && !isEnd {
 						e.postiion = AS_FROM
-					} else if len(group[1]) == 0 && len(group[3]) == 1 {
+					} else if !isTop && isEnd {
 						e.postiion = AS_ORIGIN
 					} else {
-						e.postiion = AS_ONLY
+						e.postiion = AS_ANY
 					}
-
 					asPathList = append(asPathList, e)
 
 				} else {
 					log.WithFields(log.Fields{
 						"Topic": "Policy",
 						"Type":  "AsPath Condition",
-					}).Error("cannot parse AS_PATH condition value.")
+					}).Error("does not parse AS_PATH condition value.")
 
 					return nil
 				}
 			}
-
 			c := &AsPathCondition{
 				AsPathList:  asPathList,
 				MatchOption: options,
@@ -465,36 +487,64 @@ func NewAsPathCondition(matchSet config.MatchAsPathSet, defAsPathSetList []confi
 }
 
 func (c *AsPathCondition) checkMembers(aspath []uint32, checkAll bool) bool {
-	result := false
-	if checkAll {
-		result = true
-	}
 
-	for _, member := range c.AsPathList {
-		matched := false
-		switch member.postiion {
+	checkElem := func(checkType AsnPos, regElems []*regexp.Regexp) bool {
+		aslen := len(aspath)
+		reglen := len(regElems)
+
+		if aslen < reglen {
+			return false
+		}
+
+		switch checkType {
+		case AS_ONLY:
+			if aslen != reglen {
+				return false
+			}
+			fallthrough
 		case AS_FROM:
-			matched = aspath[0] == member.asn
+			for i := 0; i < reglen; i++ {
+				if !regElems[i].MatchString(fmt.Sprintf("%d", aspath[i])) {
+					return false
+				}
+			}
+		case AS_ORIGIN:
+			for i := 0; i < reglen; i++ {
+				if !regElems[reglen-i-1].MatchString(fmt.Sprintf("%d", aspath[aslen-i-1])) {
+					return false
+				}
+			}
 		case AS_ANY:
-			for _, n := range aspath {
-				if n == member.asn {
-					matched = true
+			for i := 0; i < aslen; i++ {
+				eMatched := true
+				if aslen < i+reglen {
 					break
 				}
+				for j := 0; j < reglen; j++ {
+					if !regElems[j].MatchString(fmt.Sprintf("%d", aspath[i+j])) {
+						eMatched = false
+						break
+					}
+				}
+				if eMatched {
+					return true
+				}
 			}
-		case AS_ORIGIN:
-			matched = aspath[len(aspath)-1] == member.asn
-
-		case AS_ONLY:
-			matched = len(aspath) == 1 && aspath[0] == member.asn
-
+			return false
 		}
+		return true
+	}
 
-		if matched {
+	result := false
+	if checkAll {
+		result = true
+	}
+	for _, member := range c.AsPathList {
+		if checkElem(member.postiion, member.asRegExps) {
 			log.WithFields(log.Fields{
 				"Topic":     "Policy",
 				"Condition": "aspath length",
-				"ASN":       member.asn,
+				"ASN":       member.asStr,
 				"Position":  member.postiion,
 			}).Debug("aspath condition matched")
 
@@ -520,7 +570,7 @@ func (c *AsPathCondition) evaluate(path *table.Path) bool {
 
 	aspath := path.GetAsSeqList()
 
-	if len(aspath) == 0 {
+	if c == nil || len(aspath) == 0 {
 		return false
 	}
 
@@ -1635,7 +1685,7 @@ func PrefixSetToApiStruct(ps config.PrefixSet) *api.PrefixSet {
 	resPrefixList := make([]*api.Prefix, 0)
 	for _, p := range ps.PrefixList {
 		resPrefix := &api.Prefix{
-			IpPrefix:          p.IpPrefix,
+			IpPrefix:        p.IpPrefix,
 			MaskLengthRange: p.MasklengthRange,
 		}
 		resPrefixList = append(resPrefixList, resPrefix)
diff --git a/policy/policy_test.go b/policy/policy_test.go
index a6d4a4e4..72bf5c6c 100644
--- a/policy/policy_test.go
+++ b/policy/policy_test.go
@@ -653,6 +653,7 @@ func TestAsPathConditionEvaluate(t *testing.T) {
 		},
 	}
 
+
 	asPathSetList := []config.AsPathSet{asPathSet1, asPathSet2, asPathSet3,
 		asPathSet4, asPathSet5, asPathSet6}
 
@@ -686,9 +687,127 @@ func TestAsPathConditionEvaluate(t *testing.T) {
 
 	assert.Equal(t, true, p7.evaluate(path1))
 	assert.Equal(t, true, p8.evaluate(path2))
+}
+
+func TestMultipleAsPathConditionEvaluate(t *testing.T) {
+
+	// setup
+	// create path
+	peer := &table.PeerInfo{AS: 65001, Address: net.ParseIP("10.0.0.1")}
+	origin := bgp.NewPathAttributeOrigin(0)
+	aspathParam1 := []bgp.AsPathParamInterface{
+		bgp.NewAsPathParam(2, []uint16{65001, 65000, 54000, 65004, 65005}),
+		bgp.NewAsPathParam(1, []uint16{65001, 65010, 54000, 65004, 65005}),
+	}
+	aspath := bgp.NewPathAttributeAsPath(aspathParam1)
+	nexthop := bgp.NewPathAttributeNextHop("10.0.0.1")
+	med := bgp.NewPathAttributeMultiExitDisc(0)
+	pathAttributes := []bgp.PathAttributeInterface{origin, aspath, nexthop, med}
+	nlri := []bgp.NLRInfo{*bgp.NewNLRInfo(24, "10.10.0.101")}
+	withdrawnRoutes := []bgp.WithdrawnRoute{}
+	updateMsg1 := bgp.NewBGPUpdateMessage(withdrawnRoutes, pathAttributes, nlri)
+	table.UpdatePathAttrs4ByteAs(updateMsg1.Body.(*bgp.BGPUpdate))
+	path1 := table.ProcessMessage(updateMsg1, peer)[0]
+
+
+	// create match condition
+	asPathSet1 := config.AsPathSet{
+		AsPathSetName: "asset1",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: "^65001_65000"},
+		},
+	}
+
+	asPathSet2 := config.AsPathSet{
+		AsPathSetName: "asset2",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: "65004_65005$"},
+		},
+	}
+
+	asPathSet3 := config.AsPathSet{
+		AsPathSetName: "asset3",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: "65001_65000_54000"},
+		},
+	}
+
+	asPathSet4 := config.AsPathSet{
+		AsPathSetName: "asset4",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: "54000_65004_65005"},
+		},
+	}
 
+	asPathSet5 := config.AsPathSet{
+		AsPathSetName: "asset5",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: "^65001_65000_54000_65004_65005$"},
+		},
+	}
+
+	asPathSet6 := config.AsPathSet{
+		AsPathSetName: "asset6",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: ".*_[0-9]+_65005"},
+		},
+	}
+
+	asPathSet7 := config.AsPathSet{
+		AsPathSetName: "asset7",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: ".*_5[0-9]+_[0-9]+"},
+		},
+	}
+
+	asPathSet8 := config.AsPathSet{
+		AsPathSetName: "asset8",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: "6[0-9]+_6[0-9]+_6[0-9]+"},
+		},
+	}
+
+	asPathSet9 := config.AsPathSet{
+		AsPathSetName: "asset9",
+		AsPathList: []config.AsPath{
+			config.AsPath{AsPath: "6[0-9]+__6[0-9]+"},
+		},
+	}
+
+	asPathSetList := []config.AsPathSet{asPathSet1, asPathSet2, asPathSet3,
+		asPathSet4, asPathSet5, asPathSet6, asPathSet7, asPathSet8, asPathSet9}
+
+	createAspathC := func(name string, option config.MatchSetOptionsType) *AsPathCondition {
+		matchSet := config.MatchAsPathSet{}
+		matchSet.AsPathSet = name
+		matchSet.MatchSetOptions = option
+		p := NewAsPathCondition(matchSet, asPathSetList)
+		return p
+	}
+
+	p1 := createAspathC("asset1", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p2 := createAspathC("asset2", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p3 := createAspathC("asset3", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p4 := createAspathC("asset4", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p5 := createAspathC("asset5", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p6 := createAspathC("asset6", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p7 := createAspathC("asset7", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p8 := createAspathC("asset8", config.MATCH_SET_OPTIONS_TYPE_ANY)
+	p9 := createAspathC("asset9", config.MATCH_SET_OPTIONS_TYPE_ANY)
+
+	// test
+	assert.Equal(t, true, p1.evaluate(path1))
+	assert.Equal(t, true, p2.evaluate(path1))
+	assert.Equal(t, true, p3.evaluate(path1))
+	assert.Equal(t, true, p4.evaluate(path1))
+	assert.Equal(t, true, p5.evaluate(path1))
+	assert.Equal(t, true, p6.evaluate(path1))
+	assert.Equal(t, true, p7.evaluate(path1))
+	assert.Equal(t, false, p8.evaluate(path1))
+	assert.Equal(t, false, p9.evaluate(path1))
 }
 
+
 func TestAsPathConditionWithOtherCondition(t *testing.T) {
 
 	// setup