123 lines
2.9 KiB
Go
123 lines
2.9 KiB
Go
package main
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import (
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"io"
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"log"
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"net/http"
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"net/url"
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"sync/atomic"
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"time"
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)
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var breaker = newCircuitBreaker()
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var (
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requestsTotal uint64
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requestsAllowed uint64
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requestsBlocked uint64
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requestsBypassed uint64
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)
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func metricsSnapshot() map[string]interface{} {
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return map[string]interface{}{
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"total": atomic.LoadUint64(&requestsTotal),
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"allowed": atomic.LoadUint64(&requestsAllowed),
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"blocked": atomic.LoadUint64(&requestsBlocked),
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"bypassed": atomic.LoadUint64(&requestsBypassed),
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"circuit": circuitStateStr(breaker.State()),
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"enabled": getConfig().Enabled,
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}
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}
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func circuitStateStr(s CircuitState) string {
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switch s {
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case StateClosed: return "closed"
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case StateOpen: return "open"
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case StateHalfOpen: return "half-open"
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}
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return "unknown"
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}
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func handleInspect(w http.ResponseWriter, r *http.Request) {
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atomic.AddUint64(&requestsTotal, 1)
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cfg := getConfig()
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if !cfg.Enabled {
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atomic.AddUint64(&requestsBypassed, 1)
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proxyToBackend(w, r)
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return
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}
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if breaker.State() == StateOpen {
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atomic.AddUint64(&requestsBypassed, 1)
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log.Printf("Firewall: breaker OPEN — fail-open, passing %s %s", r.Method, r.URL.Path)
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proxyToBackend(w, r)
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return
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}
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// Inspect via WAF.
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status, err := inspect(r)
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if err != nil {
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atomic.AddUint64(&requestsBypassed, 1)
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log.Printf("Firewall: inspection error — fail-open: %v", err)
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breaker.RecordFailure()
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proxyToBackend(w, r)
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return
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}
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breaker.RecordSuccess()
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if status == 403 {
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atomic.AddUint64(&requestsBlocked, 1)
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log.Printf("Firewall: BLOCKED %s %s", r.Method, r.URL.Path)
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w.Header().Set("Content-Type", "text/html")
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w.WriteHeader(403)
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w.Write([]byte("<html><body><h1>403 Forbidden</h1><p>Blocked by Firewall</p></body></html>"))
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return
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}
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// WAF allows — proxy to backend.
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atomic.AddUint64(&requestsAllowed, 1)
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proxyToBackend(w, r)
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}
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// proxyToBackend forwards the request to Zoraxy's original upstream.
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// The original target is passed by Zoraxy via the X-Zoraxy-Uri header.
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func proxyToBackend(w http.ResponseWriter, r *http.Request) {
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cfg := getConfig()
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target, err := url.Parse(cfg.BackendURL)
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if err != nil {
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http.Error(w, "invalid backend URL", http.StatusInternalServerError)
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return
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}
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proxyReq, err := http.NewRequestWithContext(r.Context(), r.Method, target.String()+r.URL.Path, r.Body)
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if err != nil {
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http.Error(w, "proxy error", http.StatusInternalServerError)
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return
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}
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for key, vals := range r.Header {
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for _, v := range vals {
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proxyReq.Header.Add(key, v)
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}
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}
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proxyReq.Header.Set("X-Forwarded-For", r.RemoteAddr)
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client := &http.Client{Timeout: time.Duration(cfg.TimeoutMs) * time.Millisecond}
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resp, err := client.Do(proxyReq)
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if err != nil {
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http.Error(w, "backend unreachable", http.StatusBadGateway)
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return
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}
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defer resp.Body.Close()
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for key, vals := range resp.Header {
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for _, v := range vals {
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w.Header().Add(key, v)
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}
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}
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w.WriteHeader(resp.StatusCode)
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io.Copy(w, resp.Body)
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}
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