fix: harden voice-call webhook verification

extensions/voice-call/src/providers/plivo.ts

@@ -1,5 +1,5 @@
 import crypto from "node:crypto";
-import type { PlivoConfig } from "../config.js";
+import type { PlivoConfig, WebhookSecurityConfig } from "../config.js";
 import type {
   HangupCallInput,
   InitiateCallInput,
@@ -23,6 +23,8 @@ export interface PlivoProviderOptions {
   skipVerification?: boolean;
   /** Outbound ring timeout in seconds */
   ringTimeoutSec?: number;
+  /** Webhook security options (forwarded headers/allowlist) */
+  webhookSecurity?: WebhookSecurityConfig;
 }
 
 type PendingSpeak = { text: string; locale?: string };
@@ -92,6 +94,10 @@ export class PlivoProvider implements VoiceCallProvider {
     const result = verifyPlivoWebhook(ctx, this.authToken, {
       publicUrl: this.options.publicUrl,
       skipVerification: this.options.skipVerification,
+      allowedHosts: this.options.webhookSecurity?.allowedHosts,
+      trustForwardingHeaders: this.options.webhookSecurity?.trustForwardingHeaders,
+      trustedProxyIPs: this.options.webhookSecurity?.trustedProxyIPs,
+      remoteIP: ctx.remoteAddress,
     });
 
     if (!result.ok) {
@@ -112,7 +118,7 @@ export class PlivoProvider implements VoiceCallProvider {
     // Keep providerCallId mapping for later call control.
     const callUuid = parsed.get("CallUUID") || undefined;
     if (callUuid) {
-      const webhookBase = PlivoProvider.baseWebhookUrlFromCtx(ctx);
+      const webhookBase = this.baseWebhookUrlFromCtx(ctx);
       if (webhookBase) {
         this.callUuidToWebhookUrl.set(callUuid, webhookBase);
       }
@@ -444,7 +450,7 @@ export class PlivoProvider implements VoiceCallProvider {
     ctx: WebhookContext,
     opts: { flow: string; callId?: string },
   ): string | null {
-    const base = PlivoProvider.baseWebhookUrlFromCtx(ctx);
+    const base = this.baseWebhookUrlFromCtx(ctx);
     if (!base) {
       return null;
     }
@@ -458,9 +464,16 @@ export class PlivoProvider implements VoiceCallProvider {
     return u.toString();
   }
 
-  private static baseWebhookUrlFromCtx(ctx: WebhookContext): string | null {
+  private baseWebhookUrlFromCtx(ctx: WebhookContext): string | null {
     try {
-      const u = new URL(reconstructWebhookUrl(ctx));
+      const u = new URL(
+        reconstructWebhookUrl(ctx, {
+          allowedHosts: this.options.webhookSecurity?.allowedHosts,
+          trustForwardingHeaders: this.options.webhookSecurity?.trustForwardingHeaders,
+          trustedProxyIPs: this.options.webhookSecurity?.trustedProxyIPs,
+          remoteIP: ctx.remoteAddress,
+        }),
+      );
       return `${u.origin}${u.pathname}`;
     } catch {
       return null;

extensions/voice-call/src/providers/twilio.ts

@@ -1,5 +1,5 @@
 import crypto from "node:crypto";
-import type { TwilioConfig } from "../config.js";
+import type { TwilioConfig, WebhookSecurityConfig } from "../config.js";
 import type { MediaStreamHandler } from "../media-stream.js";
 import type { TelephonyTtsProvider } from "../telephony-tts.js";
 import type {
@@ -38,6 +38,8 @@ export interface TwilioProviderOptions {
   streamPath?: string;
   /** Skip webhook signature verification (development only) */
   skipVerification?: boolean;
+  /** Webhook security options (forwarded headers/allowlist) */
+  webhookSecurity?: WebhookSecurityConfig;
 }
 
 export class TwilioProvider implements VoiceCallProvider {

extensions/voice-call/src/providers/twilio/webhook.ts

@@ -12,6 +12,10 @@ export function verifyTwilioProviderWebhook(params: {
     publicUrl: params.currentPublicUrl || undefined,
     allowNgrokFreeTierLoopbackBypass: params.options.allowNgrokFreeTierLoopbackBypass ?? false,
     skipVerification: params.options.skipVerification,
+    allowedHosts: params.options.webhookSecurity?.allowedHosts,
+    trustForwardingHeaders: params.options.webhookSecurity?.trustForwardingHeaders,
+    trustedProxyIPs: params.options.webhookSecurity?.trustedProxyIPs,
+    remoteIP: params.ctx.remoteAddress,
   });
 
   if (!result.ok) {