feat(detectors): add conditional interface

pkg/detectors/detectors.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"math/big"
 	"net/url"
+	"regexp"
 	"strings"
 	"unicode"
 
@@ -44,6 +45,27 @@ type CustomResultsCleaner interface {
 	ShouldCleanResultsIrrespectiveOfConfiguration() bool
 }
 
+// ConditionalDetector is an optional interface that a detector can implement to
+// skip chunks based on specific criteria.
+type ConditionalDetector interface {
+	// ShouldScanChunk determines whether the detector should run.
+	ShouldScanChunk(chunk sources.Chunk) bool
+}
+
+var lockFilePat = regexp.MustCompile(`(^|/)(package(-lock)?\.json|yarn\.lock)$`)
+
+// Conditions is a set of common conditions to be used by ConditionalDetector.
+// (Using anonymous structs is weird, but Go has no concept of static members... https://stackoverflow.com/a/55390104)
+var Conditions = struct {
+	// LockFiles are a common source of false-positives.
+	// https://github.com/trufflesecurity/trufflehog/issues/1460
+	IsLockFile func(path string) bool
+}{
+	IsLockFile: func(path string) bool {
+		return lockFilePat.MatchString(path)
+	},
+}
+
 // Versioner is an optional interface that a detector can implement to
 // differentiate instances of the same detector type.
 type Versioner interface {

pkg/detectors/parseur/parseur.go

@@ -7,6 +7,8 @@ import (
 	"net/http"
 	"strings"
 
+	"github.com/trufflesecurity/trufflehog/v3/pkg/sources"
+
 	"github.com/trufflesecurity/trufflehog/v3/pkg/common"
 	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors"
 	"github.com/trufflesecurity/trufflehog/v3/pkg/pb/detectorspb"
@@ -18,6 +20,7 @@ type Scanner struct {
 
 // Ensure the Scanner satisfies the interface at compile time
 var _ detectors.Detector = (*Scanner)(nil)
+var _ detectors.ConditionalDetector = (*Scanner)(nil)
 
 var (
 	defaultClient = common.SaneHttpClient()
@@ -32,6 +35,13 @@ func (s Scanner) Keywords() []string {
 	return []string{"parseur"}
 }
 
+func (s Scanner) ShouldScanChunk(chunk sources.Chunk) bool {
+	if m, ok := sources.NewGitSourceMetadata(chunk.SourceType, chunk.SourceMetadata); ok {
+		return !detectors.Conditions.IsLockFile(m.File)
+	}
+	return true
+}
+
 // FromData will find and optionally verify Parseur secrets in a given set of bytes.
 func (s Scanner) FromData(ctx context.Context, verify bool, data []byte) (results []detectors.Result, err error) {
 	dataStr := string(data)

pkg/engine/engine.go

@@ -802,6 +802,11 @@ func (e *Engine) scannerWorker(ctx context.Context) {
 			}
 
 			for _, detector := range matchingDetectors {
+				if d, ok := detector.Detector.(detectors.ConditionalDetector); ok && !d.ShouldScanChunk(*chunk) {
+					ctx.Logger().V(4).Info("skipping detector for chunk", "detector", detector.Type().String(), "chunk", chunk)
+					continue
+				}
+
 				decoded.Chunk.Verify = e.shouldVerifyChunk(sourceVerify, detector, e.detectorVerificationOverrides)
 				wgDetect.Add(1)
 				e.detectableChunksChan <- detectableChunk{

pkg/sources/sources.go

@@ -45,6 +45,42 @@ type Chunk struct {
 	Verify bool
 }
 
+// GitSourceMetadata defines a common struct for Git-based source metadata.
+type GitSourceMetadata struct {
+	Repository string
+	Commit     string
+	File       string
+}
+
+func NewGitSourceMetadata(source sourcespb.SourceType, data *source_metadatapb.MetaData) (*GitSourceMetadata, bool) {
+	if data == nil {
+		return nil, false
+	}
+
+	switch source {
+	case sourcespb.SourceType_SOURCE_TYPE_GIT:
+		md := data.GetGit()
+		return &GitSourceMetadata{md.GetRepository(), md.GetCommit(), md.GetFile()}, true
+	case sourcespb.SourceType_SOURCE_TYPE_AZURE_REPOS:
+		md := data.GetAzureRepos()
+		return &GitSourceMetadata{md.GetRepository(), md.GetCommit(), md.GetFile()}, true
+	case sourcespb.SourceType_SOURCE_TYPE_BITBUCKET:
+		md := data.GetBitbucket()
+		return &GitSourceMetadata{md.GetRepository(), md.GetCommit(), md.GetFile()}, true
+	case sourcespb.SourceType_SOURCE_TYPE_GERRIT:
+		md := data.GetGerrit()
+		return &GitSourceMetadata{md.GetProject(), md.GetCommit(), md.GetFile()}, true
+	case sourcespb.SourceType_SOURCE_TYPE_GITHUB:
+		md := data.GetGithub()
+		return &GitSourceMetadata{md.GetRepository(), md.GetCommit(), md.GetFile()}, true
+	case sourcespb.SourceType_SOURCE_TYPE_GITLAB:
+		md := data.GetGitlab()
+		return &GitSourceMetadata{md.GetRepository(), md.GetCommit(), md.GetFile()}, true
+	default:
+		return nil, false
+	}
+}
+
 // ChunkingTarget specifies criteria for a targeted chunking process.
 // Instead of collecting data indiscriminately, this struct allows the caller
 // to specify particular subsets of data they're interested in. This becomes