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Block on TLS

Inspects the incoming request's TLS version and blocks if under TLSv1.2.
export default {
async fetch(request) {
try {
const tlsVersion = request.cf.tlsVersion;
// Allow only TLS versions 1.2 and 1.3
if (tlsVersion !== "TLSv1.2" && tlsVersion !== "TLSv1.3") {
return new Response("Please use TLS version 1.2 or higher.", {
status: 403,
});
}
return fetch(request);
} catch (err) {
console.error(
"request.cf does not exist in the previewer, only in production"
);
return new Response(`Error in workers script ${err.message}`, {
status: 500,
});
}
},
};
const handler: ExportedHandler = {
async fetch(request: Request) {
try {
const tlsVersion = request.cf.tlsVersion;
// Allow only TLS versions 1.2 and 1.3
if (tlsVersion !== "TLSv1.2" && tlsVersion !== "TLSv1.3") {
return new Response("Please use TLS version 1.2 or higher.", {
status: 403,
});
}
return fetch(request);
} catch (err) {
console.error(
"request.cf does not exist in the previewer, only in production"
);
return new Response(`Error in workers script ${err.message}`, {
status: 500,
});
}
},
};
export default handler;