Add URL sanitizing check

Author: ruihildt

src/helpers/domain.ts

@@ -7,6 +7,7 @@ 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 } = checkDomain(currentHost);
+    const { hasSubdomain, domain, subDomain, isMullvadNet } = checkDomain(currentHost);
     const currentDomain = hasSubdomain ? subDomain : domain;
 
     const isDomainExcluded = excludedHostsParsed.includes(currentDomain);
@@ -51,8 +51,8 @@ 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 = details.url?.endsWith('am.i.mullvad.net/json');
-    const isDNSCheck = details.url?.endsWith('dnsleak.am.i.mullvad.net/');
+    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);