Add DocuSign detector (trufflesecurity#1382)

* init

* look for client id and client secret, encode them for basis auth

* add tests

* test without checking the contents of response

* confirm access_token exists

* cleanup test

* explain in code that an undocumented grant_type is used

* remove use of deprecated ioutil, remove dead code, return errors instead of just logging

* directly pull access token

* update error text, remove redundant body close()

* import new detector into defaults

pkg/detectors/docusign/docusign.go

@@ -0,0 +1,124 @@
+package docusign
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"github.com/go-errors/errors"
+	"io"
+	"net/http"
+	"regexp"
+	"strings"
+
+	"github.com/trufflesecurity/trufflehog/v3/pkg/common"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/pb/detectorspb"
+)
+
+type Scanner struct{}
+
+type Response struct {
+	AccessToken string `json:"access_token"`
+}
+
+// Ensure the Scanner satisfies the interface at compile time.
+var _ detectors.Detector = (*Scanner)(nil)
+
+var (
+	client = common.SaneHttpClient()
+
+	// Make sure that your group is surrounded in boundary characters such as below to reduce false positives.
+	idPat     = regexp.MustCompile(detectors.PrefixRegex([]string{"integration", "id"}) + common.UUIDPattern)
+	secretPat = regexp.MustCompile(detectors.PrefixRegex([]string{"secret"}) + common.UUIDPattern)
+)
+
+// Keywords are used for efficiently pre-filtering chunks.
+// Use identifiers in the secret preferably, or the provider name.
+func (s Scanner) Keywords() []string {
+	return []string{"docusign"}
+}
+
+// FromData will find and optionally verify Docusign 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)
+
+	idMatches := idPat.FindAllStringSubmatch(dataStr, -1)
+	secretMatches := secretPat.FindAllStringSubmatch(dataStr, -1)
+
+	for _, idMatch := range idMatches {
+		if len(idMatch) != 2 {
+			continue
+		}
+		resIDMatch := strings.TrimSpace(idMatch[1])
+
+		for _, secretMatch := range secretMatches {
+			if len(secretMatch) != 2 {
+				continue
+			}
+			resSecretMatch := strings.TrimSpace(secretMatch[1])
+
+			s1 := detectors.Result{
+				DetectorType: detectorspb.DetectorType_Docusign,
+				Raw:          []byte(resIDMatch),
+				Redacted:     resIDMatch,
+				RawV2:        []byte(resIDMatch + resSecretMatch),
+			}
+
+			// Verify client id and secret pair by using an *undocumented* client_credentials grant type on the oauth2 endpoint.
+			// If verifier breaks in the future, confirm that the oauth2 endpoint is still accepting the client_credentials grant type.
+			if verify {
+				req, err := http.NewRequestWithContext(ctx, "POST", "https://account-d.docusign.com/oauth/token?grant_type=client_credentials", nil)
+				if err != nil {
+					continue
+				}
+
+				encodedCredentials := base64.StdEncoding.EncodeToString([]byte(fmt.Sprintf("%s:%s", resIDMatch, resSecretMatch)))
+
+				req.Header.Add("Accept", "application/vnd.docusign+json; version=3")
+				req.Header.Add("Authorization", fmt.Sprintf("Basic %s", encodedCredentials))
+				res, err := client.Do(req)
+
+				if err != nil {
+					return nil, errors.WrapPrefix(err, "Error making request", 0)
+				}
+
+				// Read the response body
+				body, err := io.ReadAll(res.Body)
+
+				if err != nil {
+					return nil, errors.WrapPrefix(err, "Error reading response body", 0)
+				}
+
+				// Close the response body
+				res.Body.Close()
+
+				// Parse the response body into a Response struct
+				var parsedResponse Response
+				err = json.Unmarshal(body, &parsedResponse)
+				if err != nil {
+					return nil, errors.WrapPrefix(err, "Error parsing response", 0)
+				}
+
+				if err == nil {
+					if res.StatusCode >= 200 && res.StatusCode < 300 && strings.HasPrefix(parsedResponse.AccessToken, "ey") {
+						s1.Verified = true
+					} else {
+						// This function will check false positives for common test words, but also it will make sure the key appears 'random' enough to be a real key.
+						if detectors.IsKnownFalsePositive(resIDMatch, detectors.DefaultFalsePositives, true) {
+							continue
+						}
+					}
+				}
+			}
+
+			results = append(results, s1)
+		}
+	}
+
+	return results, nil
+}
+
+func (s Scanner) Type() detectorspb.DetectorType {
+	return detectorspb.DetectorType_Docusign
+}

pkg/detectors/docusign/docusign_test.go

@@ -0,0 +1,124 @@
+//go:build detectors
+// +build detectors
+
+package docusign
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/kylelemons/godebug/pretty"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors"
+
+	"github.com/trufflesecurity/trufflehog/v3/pkg/common"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/pb/detectorspb"
+)
+
+func TestDocusign_FromChunk(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
+	defer cancel()
+	testSecrets, err := common.GetSecret(ctx, "trufflehog-testing", "detectors5")
+	if err != nil {
+		t.Fatalf("could not get test secrets from GCP: %s", err)
+	}
+	integrationKey := testSecrets.MustGetField("DOCUSIGN_INTEGRATION_KEY_ACTIVE")
+	activeSecret := testSecrets.MustGetField("DOCUSIGN_SECRET_ACTIVE")
+	inactiveSecret := testSecrets.MustGetField("DOCUSIGN_SECRET_INACTIVE")
+
+	type args struct {
+		ctx    context.Context
+		data   []byte
+		verify bool
+	}
+	tests := []struct {
+		name    string
+		s       Scanner
+		args    args
+		want    []detectors.Result
+		wantErr bool
+	}{
+		{
+			name: "found, verified",
+			s:    Scanner{},
+			args: args{
+				ctx:    context.Background(),
+				data:   []byte(fmt.Sprintf("You can find a docusign id %s and secret %s within", integrationKey, activeSecret)),
+				verify: true,
+			},
+			want: []detectors.Result{
+				{
+					DetectorType: detectorspb.DetectorType_Docusign,
+					Verified:     true,
+					RawV2:        []byte(integrationKey + activeSecret),
+					Redacted:     integrationKey,
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "found, unverified",
+			s:    Scanner{},
+			args: args{
+				ctx:    context.Background(),
+				data:   []byte(fmt.Sprintf("You can find a docusign id %s and secret %s within", integrationKey, inactiveSecret)), // the secret would satisfy the regex but not pass validation
+				verify: true,
+			},
+			want: []detectors.Result{
+				{
+					DetectorType: detectorspb.DetectorType_Docusign,
+					Verified:     false,
+					RawV2:        []byte(integrationKey + inactiveSecret),
+					Redacted:     integrationKey,
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "not found",
+			s:    Scanner{},
+			args: args{
+				ctx:    context.Background(),
+				data:   []byte("You cannot find the secret within"),
+				verify: true,
+			},
+			want:    nil,
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			s := Scanner{}
+			got, err := s.FromData(tt.args.ctx, tt.args.verify, tt.args.data)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("Docusign.FromData() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			for i := range got {
+				if len(got[i].Raw) == 0 {
+					t.Fatalf("no raw secret present: \n %+v", got[i])
+				}
+				got[i].Raw = nil
+			}
+			if diff := pretty.Compare(got, tt.want); diff != "" {
+				t.Errorf("Docusign.FromData() %s diff: (-got +want)\n%s", tt.name, diff)
+			}
+		})
+	}
+}
+
+func BenchmarkFromData(benchmark *testing.B) {
+	ctx := context.Background()
+	s := Scanner{}
+	for name, data := range detectors.MustGetBenchmarkData() {
+		benchmark.Run(name, func(b *testing.B) {
+			for n := 0; n < b.N; n++ {
+				_, err := s.FromData(ctx, false, data)
+				if err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	}
+}

pkg/engine/defaults.go

@@ -200,6 +200,7 @@ import (
 	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors/dnscheck"
 	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors/docparser"
 	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors/documo"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors/docusign"
 	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors/doppler"
 	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors/dotmailer"
 	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors/dovico"
@@ -975,6 +976,7 @@ func DefaultDetectors() []detectors.Detector {
 		&pandadoc.Scanner{},
 		&juro.Scanner{},
 		&documo.Scanner{},
+		&docusign.Scanner{},
 		&roninapp.Scanner{},
 		&doppler.Scanner{},
 		&codacy.Scanner{},

proto/detectors.proto

@@ -927,6 +927,7 @@ enum DetectorType {
   NuGetApiKey = 916;
   Aiven = 917;
   Prefect = 918;
+  Docusign = 919;
 }
 
 message Result {