Ryan Malloy c73fa9d3d1 Add extension enumeration detection and comprehensive SIP protection
Major features:
- Extension enumeration detection with 3 detection algorithms:
  - Max unique extensions threshold (default: 20 in 5 min)
  - Sequential pattern detection (e.g., 100,101,102...)
  - Rapid-fire detection (many extensions in short window)
- Prometheus metrics for all SIP Guardian operations
- SQLite persistent storage for bans and attack history
- Webhook notifications for ban/unban/suspicious events
- GeoIP-based country blocking with continent shortcuts
- Per-method rate limiting with token bucket algorithm

Bug fixes:
- Fix whitelist count always reporting zero in stats
- Fix whitelisted connections metric never incrementing
- Fix Caddyfile config not being applied to shared guardian

New files:
- enumeration.go: Extension enumeration detector
- enumeration_test.go: 14 comprehensive unit tests
- metrics.go: Prometheus metrics handler
- storage.go: SQLite persistence layer
- webhooks.go: Webhook notification system
- geoip.go: MaxMind GeoIP integration
- ratelimit.go: Per-method rate limiting

Testing:
- sandbox/ contains complete Docker Compose test environment
- All 14 enumeration tests pass
2025-12-07 15:22:28 -07:00

205 lines
5.5 KiB
Go

package sipguardian
import (
"encoding/json"
"net/http"
"strings"
"github.com/caddyserver/caddy/v2"
"github.com/caddyserver/caddy/v2/caddyconfig/caddyfile"
"github.com/caddyserver/caddy/v2/caddyconfig/httpcaddyfile"
"github.com/caddyserver/caddy/v2/modules/caddyhttp"
)
func init() {
caddy.RegisterModule(AdminHandler{})
httpcaddyfile.RegisterHandlerDirective("sip_guardian_admin", parseSIPGuardianAdmin)
// Register handler ordering so it can be used directly in handle blocks
httpcaddyfile.RegisterDirectiveOrder("sip_guardian_admin", httpcaddyfile.Before, "respond")
}
// parseSIPGuardianAdmin parses the sip_guardian_admin directive
func parseSIPGuardianAdmin(h httpcaddyfile.Helper) (caddyhttp.MiddlewareHandler, error) {
var handler AdminHandler
err := handler.UnmarshalCaddyfile(h.Dispenser)
return &handler, err
}
// AdminHandler provides HTTP endpoints to manage SIP Guardian
type AdminHandler struct {
guardian *SIPGuardian
}
func (AdminHandler) CaddyModule() caddy.ModuleInfo {
return caddy.ModuleInfo{
ID: "http.handlers.sip_guardian_admin",
New: func() caddy.Module { return new(AdminHandler) },
}
}
func (h *AdminHandler) Provision(ctx caddy.Context) error {
// Get the shared guardian instance from the global registry
guardian, err := GetOrCreateGuardian(ctx, "default")
if err != nil {
return err
}
h.guardian = guardian
return nil
}
// ServeHTTP handles admin API requests
func (h *AdminHandler) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
// Route based on path
path := r.URL.Path
switch {
case strings.HasSuffix(path, "/bans"):
return h.handleBans(w, r)
case strings.HasSuffix(path, "/stats"):
return h.handleStats(w, r)
case strings.Contains(path, "/unban/"):
return h.handleUnban(w, r, path)
case strings.Contains(path, "/ban/"):
return h.handleBan(w, r, path)
default:
return next.ServeHTTP(w, r)
}
}
// handleBans lists all banned IPs
func (h *AdminHandler) handleBans(w http.ResponseWriter, r *http.Request) error {
if r.Method != http.MethodGet {
http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
return nil
}
bans := h.guardian.GetBannedIPs()
w.Header().Set("Content-Type", "application/json")
return json.NewEncoder(w).Encode(map[string]interface{}{
"bans": bans,
"count": len(bans),
})
}
// handleStats returns current statistics
func (h *AdminHandler) handleStats(w http.ResponseWriter, r *http.Request) error {
if r.Method != http.MethodGet {
http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
return nil
}
stats := h.guardian.GetStats()
w.Header().Set("Content-Type", "application/json")
return json.NewEncoder(w).Encode(stats)
}
// handleUnban removes an IP from the ban list
func (h *AdminHandler) handleUnban(w http.ResponseWriter, r *http.Request, path string) error {
if r.Method != http.MethodPost && r.Method != http.MethodDelete {
http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
return nil
}
// Extract IP from path: /admin/sip-guardian/unban/{ip}
parts := strings.Split(path, "/unban/")
if len(parts) != 2 || parts[1] == "" {
http.Error(w, "IP address required", http.StatusBadRequest)
return nil
}
ip := strings.TrimSuffix(parts[1], "/")
if h.guardian.UnbanIP(ip) {
w.Header().Set("Content-Type", "application/json")
json.NewEncoder(w).Encode(map[string]interface{}{
"success": true,
"message": "IP unbanned",
"ip": ip,
})
} else {
w.WriteHeader(http.StatusNotFound)
w.Header().Set("Content-Type", "application/json")
json.NewEncoder(w).Encode(map[string]interface{}{
"success": false,
"message": "IP not found in ban list",
"ip": ip,
})
}
return nil
}
// handleBan manually adds an IP to the ban list
func (h *AdminHandler) handleBan(w http.ResponseWriter, r *http.Request, path string) error {
if r.Method != http.MethodPost {
http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
return nil
}
// Extract IP from path: /admin/sip-guardian/ban/{ip}
parts := strings.Split(path, "/ban/")
if len(parts) != 2 || parts[1] == "" {
http.Error(w, "IP address required", http.StatusBadRequest)
return nil
}
ip := strings.TrimSuffix(parts[1], "/")
// Parse optional reason from body
var body struct {
Reason string `json:"reason"`
}
if r.Body != nil {
json.NewDecoder(r.Body).Decode(&body)
}
if body.Reason == "" {
body.Reason = "manual_ban"
}
// Force a ban by recording max failures
h.guardian.mu.Lock()
h.guardian.failureCounts[ip] = &failureTracker{
count: h.guardian.MaxFailures,
}
h.guardian.banIP(ip, body.Reason)
h.guardian.mu.Unlock()
w.Header().Set("Content-Type", "application/json")
return json.NewEncoder(w).Encode(map[string]interface{}{
"success": true,
"message": "IP banned",
"ip": ip,
"reason": body.Reason,
})
}
// UnmarshalCaddyfile implements caddyfile.Unmarshaler for AdminHandler.
// Usage in Caddyfile:
//
// handle /api/sip-guardian/* {
// sip_guardian_admin
// }
//
// Or simply: sip_guardian_admin
func (h *AdminHandler) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
// Move past "sip_guardian_admin" token
d.Next()
// This handler doesn't have any configuration options currently
// but we need to consume any block if present
for nesting := d.Nesting(); d.NextBlock(nesting); {
return d.Errf("unknown sip_guardian_admin directive: %s", d.Val())
}
return nil
}
// Interface guards
var (
_ caddyhttp.MiddlewareHandler = (*AdminHandler)(nil)
_ caddy.Provisioner = (*AdminHandler)(nil)
_ caddyfile.Unmarshaler = (*AdminHandler)(nil)
)