feat(detectors): add Tencent Cloud credential detector

Detects Tencent Cloud SecretId (AKID-prefixed) paired with a SecretKey and
verifies the pair against the CVM DescribeRegions API using a TC3-HMAC-SHA256
signed request. Tencent returns HTTP 200 with an Error block in the body for
authentication failures, so verification inspects the response body and treats
AuthFailure.* codes as determinately invalid.

Refs #4036

Author: 0xDevNinja

pkg/detectors/tencentcloud/tencentcloud.go

@@ -0,0 +1,225 @@
+package tencentcloud
+
+import (
+	"context"
+	"crypto/hmac"
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	regexp "github.com/wasilibs/go-re2"
+
+	"github.com/trufflesecurity/trufflehog/v3/pkg/common"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/pb/detector_typepb"
+)
+
+type Scanner struct {
+	client *http.Client
+	detectors.DefaultMultiPartCredentialProvider
+}
+
+// Ensure the Scanner satisfies the interface at compile time.
+var _ detectors.Detector = (*Scanner)(nil)
+
+var (
+	defaultClient = common.SaneHttpClient()
+
+	// SecretId always starts with the "AKID" prefix followed by 32 alphanumeric characters.
+	idPat = regexp.MustCompile(`\b(AKID[A-Za-z0-9]{32})\b`)
+	// SecretKey is a generic 32-character alphanumeric string; it is paired with a SecretId.
+	secretPat = regexp.MustCompile(`\b([A-Za-z0-9]{32})\b`)
+)
+
+func (s Scanner) getClient() *http.Client {
+	if s.client != nil {
+		return s.client
+	}
+
+	return defaultClient
+}
+
+// Keywords are used for efficiently pre-filtering chunks.
+func (s Scanner) Keywords() []string {
+	return []string{"AKID"}
+}
+
+func (s Scanner) Type() detector_typepb.DetectorType {
+	return detector_typepb.DetectorType_TencentCloud
+}
+
+func (s Scanner) Description() string {
+	return "Tencent Cloud is a cloud computing platform offering compute, storage, database and 200+ other services. SecretId/SecretKey pairs grant programmatic access to the account's cloud resources."
+}
+
+// FromData will find and optionally verify Tencent Cloud 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 := make(map[string]struct{})
+	for _, match := range idPat.FindAllStringSubmatch(dataStr, -1) {
+		idMatches[match[1]] = struct{}{}
+	}
+
+	secretMatches := make(map[string]struct{})
+	for _, match := range secretPat.FindAllStringSubmatch(dataStr, -1) {
+		secretMatches[match[1]] = struct{}{}
+	}
+
+	for id := range idMatches {
+		for secret := range secretMatches {
+			// Skip low-entropy secrets to reduce false positives from generic 32-char strings.
+			if detectors.StringShannonEntropy(secret) < 3.0 {
+				continue
+			}
+
+			s1 := detectors.Result{
+				DetectorType: detector_typepb.DetectorType_TencentCloud,
+				Raw:          []byte(id),
+				RawV2:        []byte(id + ":" + secret),
+				Redacted:     id,
+				SecretParts: map[string]string{
+					"secret_id":  id,
+					"secret_key": secret,
+				},
+			}
+
+			if verify {
+				isVerified, verificationErr := verifyMatch(ctx, s.getClient(), id, secret)
+				s1.Verified = isVerified
+				s1.SetVerificationError(verificationErr, secret)
+			}
+
+			results = append(results, s1)
+
+			// Once a SecretId is verified with a SecretKey, stop pairing it with other secrets.
+			if s1.Verified {
+				break
+			}
+		}
+	}
+
+	return results, nil
+}
+
+const (
+	verifyHost    = "cvm.tencentcloudapi.com"
+	verifyService = "cvm"
+	verifyAction  = "DescribeRegions"
+	verifyVersion = "2017-03-12"
+	verifyRegion  = "ap-guangzhou"
+)
+
+// tencentResponse models the envelope every Tencent Cloud 3.0 API returns.
+// Authentication failures are reported with HTTP 200 and an Error block in the body.
+type tencentResponse struct {
+	Response struct {
+		Error *struct {
+			Code    string `json:"Code"`
+			Message string `json:"Message"`
+		} `json:"Error"`
+	} `json:"Response"`
+}
+
+func verifyMatch(ctx context.Context, client *http.Client, secretID, secretKey string) (bool, error) {
+	const payload = "{}"
+	now := time.Now().UTC()
+	timestamp := strconv.FormatInt(now.Unix(), 10)
+	date := now.Format("2006-01-02")
+
+	// Build the TC3-HMAC-SHA256 authorization header.
+	// https://www.tencentcloud.com/document/api/213/31574
+	contentType := "application/json; charset=utf-8"
+	canonicalHeaders := "content-type:" + contentType + "\nhost:" + verifyHost + "\n"
+	signedHeaders := "content-type;host"
+	hashedPayload := sha256Hex(payload)
+	canonicalRequest := strings.Join([]string{
+		http.MethodPost,
+		"/",
+		"",
+		canonicalHeaders,
+		signedHeaders,
+		hashedPayload,
+	}, "\n")
+
+	credentialScope := date + "/" + verifyService + "/tc3_request"
+	stringToSign := strings.Join([]string{
+		"TC3-HMAC-SHA256",
+		timestamp,
+		credentialScope,
+		sha256Hex(canonicalRequest),
+	}, "\n")
+
+	secretDate := hmacSHA256([]byte("TC3"+secretKey), date)
+	secretService := hmacSHA256(secretDate, verifyService)
+	secretSigning := hmacSHA256(secretService, "tc3_request")
+	signature := hex.EncodeToString(hmacSHA256(secretSigning, stringToSign))
+
+	authorization := fmt.Sprintf(
+		"TC3-HMAC-SHA256 Credential=%s/%s, SignedHeaders=%s, Signature=%s",
+		secretID, credentialScope, signedHeaders, signature,
+	)
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, "https://"+verifyHost+"/", strings.NewReader(payload))
+	if err != nil {
+		return false, err
+	}
+	req.Header.Set("Content-Type", contentType)
+	req.Header.Set("Host", verifyHost)
+	req.Header.Set("Authorization", authorization)
+	req.Header.Set("X-TC-Action", verifyAction)
+	req.Header.Set("X-TC-Version", verifyVersion)
+	req.Header.Set("X-TC-Timestamp", timestamp)
+	req.Header.Set("X-TC-Region", verifyRegion)
+
+	res, err := client.Do(req)
+	if err != nil {
+		return false, err
+	}
+	defer func() {
+		_, _ = io.Copy(io.Discard, res.Body)
+		_ = res.Body.Close()
+	}()
+
+	if res.StatusCode != http.StatusOK {
+		return false, fmt.Errorf("unexpected HTTP response status %d", res.StatusCode)
+	}
+
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		return false, err
+	}
+
+	var parsed tencentResponse
+	if err := json.Unmarshal(body, &parsed); err != nil {
+		return false, err
+	}
+
+	// No error block means the signature was accepted and the credentials are valid.
+	if parsed.Response.Error == nil {
+		return true, nil
+	}
+	// Authentication errors are determinate: the credentials are invalid.
+	if strings.HasPrefix(parsed.Response.Error.Code, "AuthFailure") {
+		return false, nil
+	}
+	// Any other error code is unexpected; surface it as an indeterminate result.
+	return false, fmt.Errorf("unexpected error code %q: %s", parsed.Response.Error.Code, parsed.Response.Error.Message)
+}
+
+func sha256Hex(s string) string {
+	h := sha256.Sum256([]byte(s))
+	return hex.EncodeToString(h[:])
+}
+
+func hmacSHA256(key []byte, msg string) []byte {
+	h := hmac.New(sha256.New, key)
+	h.Write([]byte(msg))
+	return h.Sum(nil)
+}

pkg/detectors/tencentcloud/tencentcloud_integration_test.go

@@ -0,0 +1,110 @@
+//go:build detectors
+// +build detectors
+
+package tencentcloud
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/cmpopts"
+
+	"github.com/trufflesecurity/trufflehog/v3/pkg/common"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors"
+	"github.com/trufflesecurity/trufflehog/v3/pkg/pb/detector_typepb"
+)
+
+func TestTencentCloud_FromChunk(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*10)
+	defer cancel()
+	testSecrets, err := common.GetSecret(ctx, "trufflehog-testing", "detectors5")
+	if err != nil {
+		t.Fatalf("could not get test secrets from GCP: %s", err)
+	}
+	secretID := testSecrets.MustGetField("TENCENTCLOUD_SECRET_ID")
+	secretKey := testSecrets.MustGetField("TENCENTCLOUD_SECRET_KEY")
+	inactiveSecretKey := testSecrets.MustGetField("TENCENTCLOUD_SECRET_KEY_INACTIVE")
+
+	type args struct {
+		ctx    context.Context
+		data   []byte
+		verify bool
+	}
+	tests := []struct {
+		name                string
+		s                   Scanner
+		args                args
+		want                []detectors.Result
+		wantErr             bool
+		wantVerificationErr bool
+	}{
+		{
+			name: "found, verified",
+			s:    Scanner{},
+			args: args{
+				ctx:    ctx,
+				data:   []byte(fmt.Sprintf("tencentcloud secret_id = %s secret_key = %s", secretID, secretKey)),
+				verify: true,
+			},
+			want: []detectors.Result{
+				{
+					DetectorType: detector_typepb.DetectorType_TencentCloud,
+					Verified:     true,
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "found, unverified",
+			s:    Scanner{},
+			args: args{
+				ctx:    ctx,
+				data:   []byte(fmt.Sprintf("tencentcloud secret_id = %s secret_key = %s", secretID, inactiveSecretKey)),
+				verify: true,
+			},
+			want: []detectors.Result{
+				{
+					DetectorType: detector_typepb.DetectorType_TencentCloud,
+					Verified:     false,
+				},
+			},
+			wantErr: false,
+		},
+		{
+			name: "not found",
+			s:    Scanner{},
+			args: args{
+				ctx:    ctx,
+				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 := tt.s
+			got, err := s.FromData(tt.args.ctx, tt.args.verify, tt.args.data)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("TencentCloud.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])
+				}
+				if (got[i].VerificationError() != nil) != tt.wantVerificationErr {
+					t.Fatalf("wantVerificationError = %v, verification error = %v", tt.wantVerificationErr, got[i].VerificationError())
+				}
+			}
+			ignoreOpts := cmpopts.IgnoreFields(detectors.Result{}, "Raw", "RawV2", "Redacted", "ExtraData", "SecretParts", "verificationError")
+			if diff := cmp.Diff(got, tt.want, ignoreOpts); diff != "" {
+				t.Errorf("TencentCloud.FromData() %s diff: (-got +want)\n%s", tt.name, diff)
+			}
+		})
+	}
+}