Feat: Reachability Enricher

Signed-off-by: Caroline Russell <[email protected]>

components/enrichers/reachability/main.go

@@ -0,0 +1,357 @@
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"flag"
+	"fmt"
+	"github.com/jmespath/go-jmespath"
+	v1 "github.com/ocurity/dracon/api/proto/v1"
+	"github.com/ocurity/dracon/pkg/putil"
+	"io"
+	"log"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+const defaultAnnotation = "Reachability"
+
+var (
+	readPath   string
+	writePath  string
+	annotation string
+	sliceFile  string
+)
+
+type regexes struct {
+	purlPkg             *regexp.Regexp
+	purlTrailingVersion *regexp.Regexp
+	purlVersion         *regexp.Regexp
+	filename            *regexp.Regexp
+	fileLine            *regexp.Regexp
+}
+
+// checkReachable checks if the search term is reachable
+func checkReachable(data ReachableSlice, search string, patterns regexes) (bool, error) {
+	if search == "" {
+		return false, nil
+	}
+	if result := checkReachablePurl(data, search, patterns); result == true {
+		return true, nil
+	}
+
+	match := patterns.fileLine.FindStringSubmatch(search)
+	if match != nil {
+		file := match[1]
+		lineMin, lineMax := getLnRange(match[2])
+		return filterFlows(data, file, lineMin, lineMax), nil
+	}
+	return false, errors.New(fmt.Sprintf("Invalid search term: %s", search))
+}
+
+// checkReachablePurl checks if a given pkg:version is included in the reachables
+func checkReachablePurl(data ReachableSlice, purl string, patterns regexes) bool {
+	purls := enumerateReachablePurls(data, patterns)
+	purl = strings.ToLower(purl)
+	_, exists := purls[purl]
+	if exists {
+		return true
+	}
+	return false
+}
+
+func enrichIssue(i *v1.Issue, data ReachableSlice, patterns regexes) (*v1.EnrichedIssue, error) {
+	enrichedIssue := v1.EnrichedIssue{}
+	//annotations := map[string]string{}
+	//targetType, newTarget := identifyTargetType(i.Target)
+	//var result bool
+	//var err error
+	result, err := checkReachable(data, i.Target, patterns)
+	if err != nil {
+	}
+	if result == true {
+
+	}
+	enrichedIssue = v1.EnrichedIssue{
+		RawIssue:    i,
+		Annotations: map[string]string{},
+	}
+	enrichedIssue.Annotations["reachable"] = strconv.FormatBool(result)
+	return &enrichedIssue, err
+}
+
+// enumerateReachablePurls extracts all the reached purls from the reachables
+func enumerateReachablePurls(data ReachableSlice, patterns regexes) map[string]string {
+	rawPurls, _ := jmespath.Search("reachables[].purls[]", data)
+	allPurls := make(map[string]string)
+	for _, purl := range rawPurls.([]interface{}) {
+		parsedPurls := parsePurl(purl.(string), patterns)
+		for _, pp := range parsedPurls {
+			allPurls[pp] = ""
+		}
+	}
+	return allPurls
+}
+
+// filterFlows filters flows based on reachables, filename, and line numbers.
+func filterFlows(data ReachableSlice, filename string, lnMin int, lnMax int) bool {
+	for _, flows := range data.Reachables {
+		for _, f := range flows.Flows {
+			if f.LineNumber != 0 && !contains(lnMin, lnMax, f.LineNumber) {
+				continue
+			}
+			if strings.HasSuffix(f.ParentFileName, filename) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// getLnRange extracts line numbers from a string and returns a tuple of (start, end).
+func getLnRange(value string) (int, int) {
+	if strings.Contains(value, "-") {
+		values := strings.Split(value, "-")
+		if len(values) == 2 {
+			start, err1 := strconv.Atoi(values[0])
+			end, err2 := strconv.Atoi(values[1])
+			if err1 == nil && err2 == nil {
+				return start, end
+			}
+		}
+	} else {
+		num, err := strconv.Atoi(value)
+		if err == nil {
+			return num, num
+		}
+	}
+	log.Printf("Ignoring invalid line number: %s.", value)
+	return 0, 0
+}
+
+// contains checks if an integer is in a slice.
+func contains(ln int, lnMin int, lnMax int) bool {
+	return (ln-lnMax)*(ln-lnMin) <= 0
+}
+
+// parsePurlPkgs extracts package and version variations from a purl.
+func parsePurlPkgs(matches []string, pattern *regexp.Regexp) []string {
+	// Creating a map to ensure uniqueness
+	pkgSet := make(map[string]struct{})
+
+	// Adding the packages
+	pkgSet[matches[pattern.SubexpIndex("p1")]] = struct{}{}
+	pkgSet[matches[pattern.SubexpIndex("p2")]] = struct{}{}
+
+	// Converting the map to a slice and cleaning up the packages
+	var pkgs []string
+	for pkg := range pkgSet {
+		pkg = strings.ReplaceAll(pkg, "pypi/", "")
+		pkg = strings.ReplaceAll(pkg, "npm/", "")
+		pkg = strings.ReplaceAll(pkg, "%40", "@")
+		pkgs = append(pkgs, pkg)
+	}
+
+	return pkgs
+}
+
+// parsePurlVersions returns a list of version variations from a purl.
+func parsePurlVersions(matches []string, pattern *regexp.Regexp) []string {
+	var versions []string
+	if len(matches) == 0 {
+		return versions
+	}
+
+	// Creating a map to ensure uniqueness
+	versionSet := make(map[string]struct{})
+
+	// Assuming the named groups are in the match
+	vers1 := matches[pattern.SubexpIndex("v1")]
+	vers2 := matches[pattern.SubexpIndex("v2")]
+	ext := matches[pattern.SubexpIndex("ext")]
+
+	// Adding the basic versions
+	versionSet[vers1] = struct{}{}
+	versionSet[vers2] = struct{}{}
+
+	// Adding the extended versions if ext exists
+	if ext != "" {
+		versionSet[vers1+ext] = struct{}{}
+		versionSet[vers2+ext] = struct{}{}
+	}
+
+	// Converting the map to a slice
+	for version := range versionSet {
+		versions = append(versions, version)
+	}
+
+	return versions
+}
+
+// parsePurl returns a list of permutations of pkg:version from a purl.
+func parsePurl(purl string, patterns regexes) []string {
+	purl = patterns.purlTrailingVersion.ReplaceAllString(purl, "$1@")
+	var result []string
+	var pkgs []string
+	var versions []string
+
+	if match := patterns.purlVersion.FindStringSubmatch(purl); match != nil {
+		versions = parsePurlVersions(match, patterns.purlVersion)
+		match = nil
+	}
+	if match := patterns.purlPkg.FindStringSubmatch(purl); match != nil {
+		pkgs = parsePurlPkgs(match, patterns.purlPkg)
+	}
+
+	for _, i := range pkgs {
+		for _, j := range versions {
+			result = append(result, i+":"+j)
+		}
+	}
+	return removeDuplicates(result)
+}
+
+// removeDuplicates removes duplicate strings from a slice.
+func removeDuplicates(elements []string) []string {
+	encountered := map[string]bool{}
+	result := []string{}
+
+	for v := range elements {
+		if encountered[elements[v]] == true {
+		} else {
+			encountered[elements[v]] = true
+			result = append(result, elements[v])
+		}
+	}
+	return result
+}
+
+func lookupEnvOrString(key string, defaultVal string) string {
+	if val, ok := os.LookupEnv(key); ok {
+		return val
+	}
+	return defaultVal
+}
+
+// readSlice loads the atom reachables slice
+func readSlice(sliceFile string) (ReachableSlice, error) {
+	// Define a variable to hold the JSON data
+	var data ReachableSlice
+
+	// Open the JSON file
+	file, err := os.Open(sliceFile)
+	defer func(file *os.File) {
+		err := file.Close()
+		if err != nil {
+		}
+	}(file)
+
+	if err != nil {
+		//fmt.Println("Error opening file:", err)
+		//return data, err
+	}
+
+	// Read the file content
+	byteValue, err := io.ReadAll(file)
+	if err != nil {
+		fmt.Println("Error reading file:", err)
+		//return data, err
+	}
+
+	// Unmarshal the JSON data into the variable
+	if err := json.Unmarshal(byteValue, &data); err != nil {
+		fmt.Println("Error unmarshaling JSON:", err)
+		return data, err
+	}
+
+	return data, nil
+}
+
+type ReachableSlice struct {
+	Reachables []struct {
+		Flows []struct {
+			ID                    int    `json:"id"`
+			Label                 string `json:"label"`
+			Name                  string `json:"name"`
+			FullName              string `json:"fullName"`
+			Signature             string `json:"signature"`
+			IsExternal            bool   `json:"isExternal"`
+			Code                  string `json:"code"`
+			TypeFullName          string `json:"typeFullName"`
+			ParentMethodName      string `json:"parentMethodName"`
+			ParentMethodSignature string `json:"parentMethodSignature"`
+			ParentFileName        string `json:"parentFileName"`
+			ParentPackageName     string `json:"parentPackageName"`
+			ParentClassName       string `json:"parentClassName"`
+			LineNumber            int    `json:"lineNumber"`
+			ColumnNumber          int    `json:"columnNumber"`
+			Tags                  string `json:"tags"`
+		} `json:"flows"`
+		Purls []string `json:"purls"`
+	} `json:"reachables"`
+}
+
+func run() {
+	res, err := putil.LoadTaggedToolResponse(readPath)
+	if err != nil {
+		log.Fatalf("could not load tool response from path %s , error:%v", readPath, err)
+	}
+	//if annotation == "" {
+	//	annotation = defaultAnnotation
+	//}
+	data, err := readSlice(sliceFile)
+	patterns := regexes{
+		purlPkg:             regexp.MustCompile(`(?P<p1>[^/:]+/(?P<p2>[^/]+))(?:(?:.|/)v\d+)?@`),
+		purlTrailingVersion: regexp.MustCompile(`[./]v\d+@`),
+		purlVersion:         regexp.MustCompile(`@(?P<v1>v?(?P<v2>[\d.]+){1,3})(?P<ext>[^?\s]+)?`),
+		filename:            regexp.MustCompile(`[^/]+[^/]?`),
+		fileLine:            regexp.MustCompile(`(?P<file>[^/]+):(?P<line>[\d-]+)`),
+	}
+
+	for _, r := range res {
+		enrichedIssues := []*v1.EnrichedIssue{}
+		for _, i := range r.GetIssues() {
+			eI, err := enrichIssue(i, data, patterns)
+			if err != nil {
+				log.Println(err)
+				continue
+			}
+			enrichedIssues = append(enrichedIssues, eI)
+		}
+		if len(enrichedIssues) > 0 {
+			if err := putil.WriteEnrichedResults(r, enrichedIssues,
+				filepath.Join(writePath, fmt.Sprintf("%s.reachability.enriched.pb", r.GetToolName())),
+			); err != nil {
+				log.Fatal(err)
+			}
+		} else {
+			log.Println("no enriched issues were created for", r.GetToolName())
+		}
+		if len(r.GetIssues()) > 0 {
+			scanStartTime := r.GetScanInfo().GetScanStartTime().AsTime()
+			if err := putil.WriteResults(
+				r.GetToolName(),
+				r.GetIssues(),
+				filepath.Join(writePath, fmt.Sprintf("%s.raw.pb", r.GetToolName())),
+				r.GetScanInfo().GetScanUuid(),
+				scanStartTime,
+				r.GetScanInfo().GetScanTags(),
+			); err != nil {
+				log.Fatalf("could not write results: %s", err)
+			}
+		}
+
+	}
+}
+
+func main() {
+	flag.StringVar(&readPath, "read_path", lookupEnvOrString("READ_PATH", ""), "where to find producer results")
+	flag.StringVar(&writePath, "write_path", lookupEnvOrString("WRITE_PATH", ""), "where to put enriched results")
+	flag.StringVar(&annotation, "annotation", lookupEnvOrString("ANNOTATION", defaultAnnotation), "what is the annotation this enricher will add to the issues, by default `Reachability`")
+	flag.StringVar(&sliceFile, "atom_slice", lookupEnvOrString("ATOM_SLICE", ""), "location of the atom slice file")
+	flag.Parse()
+	run()
+}