feat(15-03): add Elasticsearch, Kibana, and Splunk ReconSource implementations

- ElasticsearchSource: POST _search API with query_string, parse hits._source
- KibanaSource: GET saved_objects/_find API with kbn-xsrf header
- SplunkSource: GET search/jobs/export API with newline-delimited JSON parsing
- All sources use ciLogKeyPattern for key detection
- Tests use httptest mocks for each API endpoint

pkg/recon/sources/kibana.go

@@ -0,0 +1,114 @@
+package sources
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"time"
+
+	"golang.org/x/time/rate"
+
+	"github.com/salvacybersec/keyhunter/pkg/providers"
+	"github.com/salvacybersec/keyhunter/pkg/recon"
+)
+
+// KibanaSource searches exposed Kibana instances for API keys in saved objects
+// such as dashboards, visualizations, and index patterns. Many Kibana instances
+// are left unauthenticated, exposing the saved objects API.
+type KibanaSource struct {
+	BaseURL  string
+	Registry *providers.Registry
+	Limiters *recon.LimiterRegistry
+	Client   *Client
+}
+
+var _ recon.ReconSource = (*KibanaSource)(nil)
+
+func (s *KibanaSource) Name() string              { return "kibana" }
+func (s *KibanaSource) RateLimit() rate.Limit      { return rate.Every(2 * time.Second) }
+func (s *KibanaSource) Burst() int                 { return 3 }
+func (s *KibanaSource) RespectsRobots() bool       { return false }
+func (s *KibanaSource) Enabled(_ recon.Config) bool { return true }
+
+// kibanaSavedObjectsResponse represents the Kibana saved objects API response.
+type kibanaSavedObjectsResponse struct {
+	SavedObjects []kibanaSavedObject `json:"saved_objects"`
+}
+
+type kibanaSavedObject struct {
+	ID         string          `json:"id"`
+	Type       string          `json:"type"`
+	Attributes json.RawMessage `json:"attributes"`
+}
+
+func (s *KibanaSource) Sweep(ctx context.Context, query string, out chan<- recon.Finding) error {
+	base := s.BaseURL
+	if base == "" {
+		base = "http://localhost:5601"
+	}
+	client := s.Client
+	if client == nil {
+		client = NewClient()
+	}
+
+	queries := BuildQueries(s.Registry, "kibana")
+	if len(queries) == 0 {
+		return nil
+	}
+
+	for _, q := range queries {
+		if err := ctx.Err(); err != nil {
+			return err
+		}
+
+		if s.Limiters != nil {
+			if err := s.Limiters.Wait(ctx, s.Name(), s.RateLimit(), s.Burst(), false); err != nil {
+				return err
+			}
+		}
+
+		// Search saved objects (dashboards and visualizations).
+		searchURL := fmt.Sprintf(
+			"%s/api/saved_objects/_find?type=visualization&type=dashboard&search=%s&per_page=20",
+			base, url.QueryEscape(q),
+		)
+		req, err := http.NewRequestWithContext(ctx, http.MethodGet, searchURL, nil)
+		if err != nil {
+			continue
+		}
+		req.Header.Set("kbn-xsrf", "true")
+
+		resp, err := client.Do(ctx, req)
+		if err != nil {
+			continue
+		}
+
+		data, err := io.ReadAll(io.LimitReader(resp.Body, 512*1024))
+		_ = resp.Body.Close()
+		if err != nil {
+			continue
+		}
+
+		var result kibanaSavedObjectsResponse
+		if err := json.Unmarshal(data, &result); err != nil {
+			continue
+		}
+
+		for _, obj := range result.SavedObjects {
+			attrs := string(obj.Attributes)
+			if ciLogKeyPattern.MatchString(attrs) {
+				out <- recon.Finding{
+					ProviderName: q,
+					Source:       fmt.Sprintf("%s/app/kibana#/%s/%s", base, obj.Type, obj.ID),
+					SourceType:   "recon:kibana",
+					Confidence:   "medium",
+					DetectedAt:   time.Now(),
+				}
+			}
+		}
+	}
+	return nil
+}