feat: report unknowns in sbom (#2998)

Signed-off-by: Keith Zantow <kzantow@gmail.com>
Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>
Co-authored-by: Alex Goodman <wagoodman@users.noreply.github.com>

syft/pkg/cataloger/debian/parse_dpkg_db.go

@@ -15,6 +15,7 @@ import (
 
 	"github.com/anchore/syft/internal"
 	"github.com/anchore/syft/internal/log"
+	"github.com/anchore/syft/internal/unknown"
 	"github.com/anchore/syft/syft/artifact"
 	"github.com/anchore/syft/syft/file"
 	"github.com/anchore/syft/syft/pkg"
@@ -39,7 +40,7 @@ func parseDpkgDB(_ context.Context, resolver file.Resolver, env *generic.Environ
 		pkgs = append(pkgs, p)
 	}
 
-	return pkgs, nil, nil
+	return pkgs, nil, unknown.IfEmptyf(pkgs, "unable to determine packages")
 }
 
 func findDpkgInfoFiles(name string, resolver file.Resolver, dbLocation file.Location) []file.Location {

syft/pkg/cataloger/debian/parse_dpkg_db_test.go

@@ -257,6 +257,17 @@ func Test_parseDpkgStatus(t *testing.T) {
 	}
 }
 
+func Test_corruptEntry(t *testing.T) {
+	f, err := os.Open("test-fixtures/var/lib/dpkg/status.d/corrupt")
+	require.NoError(t, err)
+	t.Cleanup(func() { require.NoError(t, f.Close()) })
+
+	reader := bufio.NewReader(f)
+
+	_, err = parseDpkgStatus(reader)
+	require.Error(t, err)
+}
+
 func TestSourceVersionExtract(t *testing.T) {
 	tests := []struct {
 		name     string
@@ -312,7 +323,7 @@ func Test_parseDpkgStatus_negativeCases(t *testing.T) {
 		{
 			name:    "no more packages",
 			input:   `Package: apt`,
-			wantErr: require.NoError,
+			wantErr: requireAs(errors.New("unable to determine packages")),
 		},
 		{
 			name: "duplicated key",

syft/pkg/cataloger/debian/test-fixtures/var/lib/dpkg/status.d/corrupt

@@ -0,0 +1,6 @@
+Pakij: apt
+Stratus: install ok installed
+Prioority: required
+Section: admin
+Insterface to the configuration settings
+  * apt-key as an interface to manage authentication keys