Refactor conncheck from extension detection

Author: ruihildt

src/helpers/domain.ts

@@ -7,7 +7,6 @@ export const checkDomain = (host: string) => {
     hasSubdomain: Boolean(parsed.subdomain),
     subDomain: host,
     domain: parsed.domain || host,
-    isMullvadNet: parsed.domain === 'mullvad.net',
   };
 };
 

src/helpers/socksProxy/socksProxy.ts

@@ -30,7 +30,7 @@ export const handleProxyRequest = async (details: browser.proxy._OnRequestDetail
     const hostProxiesDetailsParsed: Record<string, ProxyDetails> = JSON.parse(hostProxiesDetails);
 
     const currentHost = getCurrentHost(details);
-    const { hasSubdomain, domain, subDomain, isMullvadNet } = checkDomain(currentHost);
+    const { hasSubdomain, domain, subDomain } = checkDomain(currentHost);
     const currentDomain = hasSubdomain ? subDomain : domain;
 
     const isDomainExcluded = excludedHostsParsed.includes(currentDomain);
@@ -50,13 +50,7 @@ export const handleProxyRequest = async (details: browser.proxy._OnRequestDetail
 
     // 3. When the request if a conncheck/DNS check originating from the extension,
     // we want to use the same proxy as the active tab, to get a consistent conncheck result
-    const isExtensionRequest = details.documentUrl?.startsWith('moz-extension://');
-    const isConnCheck = isMullvadNet && details.url?.endsWith('am.i.mullvad.net/json');
-    const isDNSCheck = isMullvadNet && details.url?.endsWith('dnsleak.am.i.mullvad.net/');
-
-    const isExtConnCheck = isExtensionRequest && (isConnCheck || isDNSCheck);
-
-    if (isExtConnCheck) {
+    if (isExtConnCheck(details)) {
       return getProxyForExtensionConnectionCheck(
         isGlobalProxyEnabled,
         globalConfigParsed,
@@ -115,6 +109,17 @@ const getCurrentHost = (details: RequestDetails) => {
   return new URL(details.url).hostname;
 };
 
+const isExtConnCheck = (details: RequestDetails): boolean => {
+  const isExtensionRequest = Boolean(details.documentUrl?.startsWith('moz-extension://'));
+  const isConnCheck =
+    details.url === 'https://ipv4.am.i.mullvad.net/json' ||
+    details.url === 'https://ipv6.am.i.mullvad.net/json';
+  const isDNSCheck =
+    checkDomain(details.url).domain === 'mullvad.net' && details.url.endsWith('am.i.mullvad.net/');
+
+  return isExtensionRequest && (isConnCheck || isDNSCheck);
+};
+
 export const isLocalOrReservedIP = (hostname: string) => {
   if (hostname.includes('localhost')) return true;
   if (!ipaddr.isValid(hostname)) return false;