Mirrors/thelounge
2
0
Fork 0
mirror of https://github.com/thelounge/thelounge synced 2024-11-24 21:13:06 +00:00
Code Issues Projects Releases Packages Wiki Activity

don't crash on rDNS failure

Browse source 
Node apparently throws even on valid ipv6 input in certain environments,
probably due to the DNS server returning SERVFAIL.
Guard against it and fallback with the plain IP

Fixes: https://github.com/thelounge/thelounge/issues/4768
This commit is contained in:
Reto Brunner 2023-11-03 20:40:56 +01:00
parent f999db99c7
commit 8c54cd50d8
1 changed files with 30 additions and 18 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

48
server/server.ts
View file

@ -1015,28 +1015,40 @@ function performAuthentication(this: Socket, data) {
}
function reverseDnsLookup(ip: string, callback: (hostname: string) => void) {
dns.reverse(ip, (reverseErr, hostnames) => {
if (reverseErr || hostnames.length < 1) {
return callback(ip);
}
dns.resolve(hostnames[0], net.isIP(ip) === 6 ? "AAAA" : "A", (resolveErr, resolvedIps) => {
// TODO: investigate SoaRecord class
if (!Array.isArray(resolvedIps)) {
// node can throw, even if we provide valid input based on the DNS server
// returning SERVFAIL it seems: https://github.com/thelounge/thelounge/issues/4768
// so we manually resolve with the ip as a fallback in case something fails
try {
dns.reverse(ip, (reverseErr, hostnames) => {
if (reverseErr || hostnames.length < 1) {
return callback(ip);
}
if (resolveErr || resolvedIps.length < 1) {
return callback(ip);
}
dns.resolve(
hostnames[0],
net.isIP(ip) === 6 ? "AAAA" : "A",
(resolveErr, resolvedIps) => {
// TODO: investigate SoaRecord class
if (!Array.isArray(resolvedIps)) {
return callback(ip);
}
for (const resolvedIp of resolvedIps) {
if (ip === resolvedIp) {
return callback(hostnames[0]);
if (resolveErr || resolvedIps.length < 1) {
return callback(ip);
}
for (const resolvedIp of resolvedIps) {
if (ip === resolvedIp) {
return callback(hostnames[0]);
}
}
return callback(ip);
}
}
return callback(ip);
);
});
});
} catch (err) {
log.error(`failed to resolve rDNS for ${ip}, using ip instead`, (err as any).toString());
setImmediate(callback, ip); // makes sure we always behave asynchronously
}
}