feat(16-02): add SecurityTrails source and wire all three Phase 16-02 sources

- SecurityTrailsSource enumerates subdomains via API, probes config endpoints
- Credential-gated via SECURITYTRAILS_API_KEY env var
- RegisterAll extended to 70 sources (67 Phase 10-15 + 3 Phase 16)
- cmd/recon.go wires SecurityTrails API key from env/viper

cmd/recon.go

@@ -168,6 +168,7 @@ func buildReconEngine() *recon.Engine {
 		NetlasAPIKey:      firstNonEmpty(os.Getenv("NETLAS_API_KEY"), viper.GetString("recon.netlas.api_key")),
 		BinaryEdgeAPIKey:  firstNonEmpty(os.Getenv("BINARYEDGE_API_KEY"), viper.GetString("recon.binaryedge.api_key")),
 		CircleCIToken:        firstNonEmpty(os.Getenv("CIRCLECI_TOKEN"), viper.GetString("recon.circleci.token")),
+		SecurityTrailsAPIKey: firstNonEmpty(os.Getenv("SECURITYTRAILS_API_KEY"), viper.GetString("recon.securitytrails.api_key")),
 	}
 	sources.RegisterAll(e, cfg)
 	return e

pkg/recon/sources/register.go

@@ -52,6 +52,9 @@ type SourcesConfig struct {
 	// Phase 14: CI/CD source tokens.
 	CircleCIToken string
 
+	// Phase 16: DNS/threat intel source tokens.
+	SecurityTrailsAPIKey string
+
 	// Registry drives query generation for every source via BuildQueries.
 	Registry *providers.Registry
 	// Limiters is the shared per-source rate-limiter registry.
@@ -61,8 +64,8 @@ type SourcesConfig struct {
 // RegisterAll registers every Phase 10 code-hosting, Phase 11 search engine /
 // paste site, Phase 12 IoT scanner / cloud storage, Phase 13 package
 // registry / container / IaC, Phase 14 CI/CD log / web archive / frontend
-// leak, and Phase 15 forum / collaboration tool / log aggregator source on
+// leak, Phase 15 forum / collaboration tool / log aggregator, and Phase 16
-// engine (67 sources total).
+// mobile / DNS / threat intel source on engine (70 sources total).
 //
 // All sources are registered unconditionally so that cmd/recon.go can surface
 // the full catalog via `keyhunter recon list` regardless of which credentials
@@ -282,4 +285,13 @@ func RegisterAll(engine *recon.Engine, cfg SourcesConfig) {
 	engine.Register(&SplunkSource{Registry: reg, Limiters: lim})
 	engine.Register(&GrafanaSource{Registry: reg, Limiters: lim})
 	engine.Register(&SentrySource{Registry: reg, Limiters: lim})
+
+	// Phase 16: Mobile, DNS, and threat intel sources.
+	engine.Register(&APKMirrorSource{Registry: reg, Limiters: lim})
+	engine.Register(&CrtShSource{Registry: reg, Limiters: lim})
+	engine.Register(&SecurityTrailsSource{
+		APIKey:   cfg.SecurityTrailsAPIKey,
+		Registry: reg,
+		Limiters: lim,
+	})
 }

pkg/recon/sources/securitytrails.go

@@ -0,0 +1,189 @@
+package sources
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+
+	"golang.org/x/time/rate"
+
+	"github.com/salvacybersec/keyhunter/pkg/providers"
+	"github.com/salvacybersec/keyhunter/pkg/recon"
+)
+
+// SecurityTrailsSource searches SecurityTrails DNS/subdomain data for API key
+// exposure. It enumerates subdomains for a target domain and probes config
+// endpoints, and also checks DNS history records (TXT records may contain keys).
+type SecurityTrailsSource struct {
+	APIKey   string
+	BaseURL  string
+	Registry *providers.Registry
+	Limiters *recon.LimiterRegistry
+	Client   *Client
+
+	// ProbeBaseURL overrides the scheme+host used when probing discovered
+	// subdomains. Tests set this to the httptest server URL.
+	ProbeBaseURL string
+}
+
+var _ recon.ReconSource = (*SecurityTrailsSource)(nil)
+
+func (s *SecurityTrailsSource) Name() string         { return "securitytrails" }
+func (s *SecurityTrailsSource) RateLimit() rate.Limit { return rate.Every(2 * time.Second) }
+func (s *SecurityTrailsSource) Burst() int            { return 5 }
+func (s *SecurityTrailsSource) RespectsRobots() bool  { return false }
+
+func (s *SecurityTrailsSource) Enabled(_ recon.Config) bool {
+	return s.APIKey != ""
+}
+
+// securityTrailsSubdomains represents the subdomain listing API response.
+type securityTrailsSubdomains struct {
+	Subdomains []string `json:"subdomains"`
+}
+
+func (s *SecurityTrailsSource) Sweep(ctx context.Context, query string, out chan<- recon.Finding) error {
+	base := s.BaseURL
+	if base == "" {
+		base = "https://api.securitytrails.com/v1"
+	}
+	client := s.Client
+	if client == nil {
+		client = NewClient()
+	}
+
+	if query == "" || !strings.Contains(query, ".") {
+		return nil
+	}
+
+	// Phase 1: Enumerate subdomains.
+	if s.Limiters != nil {
+		if err := s.Limiters.Wait(ctx, s.Name(), s.RateLimit(), s.Burst(), false); err != nil {
+			return err
+		}
+	}
+
+	subURL := fmt.Sprintf("%s/domain/%s/subdomains?children_only=false", base, query)
+	subReq, err := http.NewRequestWithContext(ctx, http.MethodGet, subURL, nil)
+	if err != nil {
+		return err
+	}
+	subReq.Header.Set("APIKEY", s.APIKey)
+
+	subResp, err := client.Do(ctx, subReq)
+	if err != nil {
+		return nil // non-fatal
+	}
+
+	subData, err := io.ReadAll(io.LimitReader(subResp.Body, 512*1024))
+	_ = subResp.Body.Close()
+	if err != nil {
+		return nil
+	}
+
+	var subResult securityTrailsSubdomains
+	if err := json.Unmarshal(subData, &subResult); err != nil {
+		return nil
+	}
+
+	// Build FQDNs and limit to 20.
+	var fqdns []string
+	for _, sub := range subResult.Subdomains {
+		fqdns = append(fqdns, sub+"."+query)
+		if len(fqdns) >= 20 {
+			break
+		}
+	}
+
+	// Probe config endpoints on each subdomain.
+	probeClient := &http.Client{Timeout: 5 * time.Second}
+	for _, fqdn := range fqdns {
+		if err := ctx.Err(); err != nil {
+			return err
+		}
+		s.probeSubdomain(ctx, probeClient, fqdn, out)
+	}
+
+	// Phase 2: Check DNS history for key patterns in TXT records.
+	if s.Limiters != nil {
+		if err := s.Limiters.Wait(ctx, s.Name(), s.RateLimit(), s.Burst(), false); err != nil {
+			return err
+		}
+	}
+
+	dnsURL := fmt.Sprintf("%s/domain/%s", base, query)
+	dnsReq, err := http.NewRequestWithContext(ctx, http.MethodGet, dnsURL, nil)
+	if err != nil {
+		return nil
+	}
+	dnsReq.Header.Set("APIKEY", s.APIKey)
+
+	dnsResp, err := client.Do(ctx, dnsReq)
+	if err != nil {
+		return nil
+	}
+
+	dnsData, err := io.ReadAll(io.LimitReader(dnsResp.Body, 512*1024))
+	_ = dnsResp.Body.Close()
+	if err != nil {
+		return nil
+	}
+
+	if ciLogKeyPattern.Match(dnsData) {
+		out <- recon.Finding{
+			ProviderName: query,
+			Source:       dnsURL,
+			SourceType:   "recon:securitytrails",
+			Confidence:   "medium",
+			DetectedAt:   time.Now(),
+		}
+	}
+
+	return nil
+}
+
+// probeSubdomain checks well-known config endpoints for key patterns.
+func (s *SecurityTrailsSource) probeSubdomain(ctx context.Context, probeClient *http.Client, subdomain string, out chan<- recon.Finding) {
+	for _, ep := range configProbeEndpoints {
+		if err := ctx.Err(); err != nil {
+			return
+		}
+
+		var probeURL string
+		if s.ProbeBaseURL != "" {
+			probeURL = s.ProbeBaseURL + "/" + subdomain + ep
+		} else {
+			probeURL = "https://" + subdomain + ep
+		}
+
+		req, err := http.NewRequestWithContext(ctx, http.MethodGet, probeURL, nil)
+		if err != nil {
+			continue
+		}
+
+		resp, err := probeClient.Do(req)
+		if err != nil {
+			continue
+		}
+
+		body, err := io.ReadAll(io.LimitReader(resp.Body, 64*1024))
+		_ = resp.Body.Close()
+		if err != nil {
+			continue
+		}
+
+		if resp.StatusCode == http.StatusOK && ciLogKeyPattern.Match(body) {
+			out <- recon.Finding{
+				ProviderName: subdomain,
+				Source:       probeURL,
+				SourceType:   "recon:securitytrails",
+				Confidence:   "high",
+				DetectedAt:   time.Now(),
+			}
+		}
+	}
+}

pkg/recon/sources/securitytrails_test.go

@@ -0,0 +1,180 @@
+package sources
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/salvacybersec/keyhunter/pkg/recon"
+)
+
+func TestSecurityTrails_Name(t *testing.T) {
+	s := &SecurityTrailsSource{}
+	if s.Name() != "securitytrails" {
+		t.Fatalf("expected securitytrails, got %s", s.Name())
+	}
+}
+
+func TestSecurityTrails_Enabled(t *testing.T) {
+	s := &SecurityTrailsSource{}
+	if s.Enabled(recon.Config{}) {
+		t.Fatal("SecurityTrailsSource should be disabled without API key")
+	}
+
+	s.APIKey = "test-key"
+	if !s.Enabled(recon.Config{}) {
+		t.Fatal("SecurityTrailsSource should be enabled with API key")
+	}
+}
+
+func TestSecurityTrails_Sweep(t *testing.T) {
+	// API server mocks SecurityTrails endpoints.
+	apiMux := http.NewServeMux()
+
+	// Subdomain enumeration.
+	apiMux.HandleFunc("/domain/example.com/subdomains", func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("APIKEY") != "test-key" {
+			http.Error(w, "unauthorized", http.StatusUnauthorized)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"subdomains":["api","staging"]}`))
+	})
+
+	// DNS history.
+	apiMux.HandleFunc("/domain/example.com", func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("APIKEY") != "test-key" {
+			http.Error(w, "unauthorized", http.StatusUnauthorized)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"current_dns":{"txt":{"values":[{"value":"token = sk-proj-ABCDEF1234567890abcdef"}]}}}`))
+	})
+
+	apiSrv := httptest.NewServer(apiMux)
+	defer apiSrv.Close()
+
+	// Probe server.
+	probeMux := http.NewServeMux()
+	probeMux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasSuffix(r.URL.Path, "/.env") {
+			_, _ = w.Write([]byte(`SECRET_KEY = "sk-proj-ABCDEF1234567890abcdef"`))
+			return
+		}
+		http.NotFound(w, r)
+	})
+	probeSrv := httptest.NewServer(probeMux)
+	defer probeSrv.Close()
+
+	s := &SecurityTrailsSource{
+		APIKey:       "test-key",
+		BaseURL:      apiSrv.URL,
+		Client:       NewClient(),
+		ProbeBaseURL: probeSrv.URL,
+	}
+
+	out := make(chan recon.Finding, 20)
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	err := s.Sweep(ctx, "example.com", out)
+	close(out)
+	if err != nil {
+		t.Fatalf("Sweep error: %v", err)
+	}
+
+	var findings []recon.Finding
+	for f := range out {
+		findings = append(findings, f)
+	}
+	if len(findings) == 0 {
+		t.Fatal("expected at least one finding from SecurityTrails")
+	}
+
+	// Check that we got both probe findings and DNS history findings.
+	var probeFound, dnsFound bool
+	for _, f := range findings {
+		if f.SourceType != "recon:securitytrails" {
+			t.Fatalf("expected recon:securitytrails, got %s", f.SourceType)
+		}
+		if strings.Contains(f.Source, "/.env") {
+			probeFound = true
+		}
+		if strings.Contains(f.Source, "/domain/example.com") && !strings.Contains(f.Source, "subdomains") {
+			dnsFound = true
+		}
+	}
+	if !probeFound {
+		t.Fatal("expected probe finding from SecurityTrails")
+	}
+	if !dnsFound {
+		t.Fatal("expected DNS history finding from SecurityTrails")
+	}
+}
+
+func TestSecurityTrails_Sweep_SkipsKeywords(t *testing.T) {
+	s := &SecurityTrailsSource{
+		APIKey: "test-key",
+		Client: NewClient(),
+	}
+
+	out := make(chan recon.Finding, 10)
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	err := s.Sweep(ctx, "sk-proj-", out)
+	close(out)
+	if err != nil {
+		t.Fatalf("Sweep error: %v", err)
+	}
+
+	var findings []recon.Finding
+	for f := range out {
+		findings = append(findings, f)
+	}
+	if len(findings) != 0 {
+		t.Fatalf("expected no findings for keyword query, got %d", len(findings))
+	}
+}
+
+func TestSecurityTrails_Sweep_NoSubdomains(t *testing.T) {
+	apiMux := http.NewServeMux()
+	apiMux.HandleFunc("/domain/empty.example.com/subdomains", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"subdomains":[]}`))
+	})
+	apiMux.HandleFunc("/domain/empty.example.com", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"current_dns":{}}`))
+	})
+
+	apiSrv := httptest.NewServer(apiMux)
+	defer apiSrv.Close()
+
+	s := &SecurityTrailsSource{
+		APIKey:  "test-key",
+		BaseURL: apiSrv.URL,
+		Client:  NewClient(),
+	}
+
+	out := make(chan recon.Finding, 10)
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	err := s.Sweep(ctx, "empty.example.com", out)
+	close(out)
+	if err != nil {
+		t.Fatalf("Sweep error: %v", err)
+	}
+
+	var findings []recon.Finding
+	for f := range out {
+		findings = append(findings, f)
+	}
+	if len(findings) != 0 {
+		t.Fatalf("expected no findings, got %d", len(findings))
+	}
+}