Files
pangolin/server/private/lib/certificates/dns-validator.ts
T
2026-09-09 16:42:53 -04:00

335 lines
13 KiB
TypeScript

/*
* This file is part of a proprietary work.
*
* Copyright (c) 2025-2026 Fossorial, Inc.
* All rights reserved.
*
* This file is licensed under the Fossorial Commercial License.
* You may not use this file except in compliance with the License.
* Unauthorized use, copying, modification, or distribution is strictly prohibited.
*
* This file is not licensed under the AGPLv3.
*/
import { eq, and, lt } from "drizzle-orm";
import * as dns from "dns/promises";
import { privateConfig as config } from "#private/lib/config";
import { db, domains, DnsRecord, dnsRecords, Domain } from "@server/db";
import logger from "@server/logger";
import { lockManager } from "../lock";
export const DNS_VALIDATOR_MAX_TRIES = 300;
export class DNSValidator {
private static readonly MAX_TRIES = DNS_VALIDATOR_MAX_TRIES;
constructor() {}
async validateAll(): Promise<void> {
// Get all domains that are not yet verified and haven't exceeded max tries
const unverifiedDomains: Domain[] = await db
.select()
.from(domains)
.where(
and(
eq(domains.verified, false),
lt(domains.tries, DNSValidator.MAX_TRIES)
)
);
if (unverifiedDomains.length === 0) {
logger.debug("No unverified domains found for DNS validation");
return;
}
logger.info(`Validating ${unverifiedDomains.length} DNS records`);
for (const domain of unverifiedDomains) {
const lockKey = `dns:${domain.baseDomain}`;
const lockToken = await lockManager.acquireLock(lockKey);
if (!lockToken) {
logger.debug(
`Could not acquire lock for DNS validation: ${domain.baseDomain}`
);
continue;
}
try {
const isValid = await this.validateDomain(domain);
if (isValid) {
await db
.update(domains)
.set({
verified: true,
failed: false,
tries: 0,
errorMessage: null
})
.where(eq(domains.domainId, domain.domainId));
logger.info(
`Domain ${domain.baseDomain} validated successfully`
);
} else {
const newTries = domain.tries + 1;
const shouldMarkAsFailed =
newTries >= DNSValidator.MAX_TRIES;
await db
.update(domains)
.set({
tries: newTries,
failed: shouldMarkAsFailed
})
.where(eq(domains.domainId, domain.domainId));
if (shouldMarkAsFailed) {
logger.warn(
`Domain ${domain.baseDomain} exceeded maximum tries (${DNSValidator.MAX_TRIES}), marking as failed`
);
} else {
logger.debug(
`Domain ${domain.baseDomain} did not validate (attempt ${newTries}/${DNSValidator.MAX_TRIES})`
);
}
}
} catch (err) {
logger.warn(
`Error validating domain ${domain.baseDomain}:`,
err
);
// Increment tries even on error
const newTries = domain.tries + 1;
const shouldMarkAsFailed = newTries >= DNSValidator.MAX_TRIES;
await db
.update(domains)
.set({
tries: newTries,
failed: shouldMarkAsFailed
})
.where(eq(domains.domainId, domain.domainId));
} finally {
await lockManager.releaseLock(lockKey, lockToken);
}
}
}
async validateDomain(
domain: Domain,
opts: { forceRecheck?: boolean } = {}
): Promise<boolean> {
const { forceRecheck = false } = opts;
const resolver = new dns.Resolver();
const servers = config.getRawConfig().acme?.dns_resolvers;
if (!servers || servers.length === 0) {
throw new Error("No DNS resolvers configured");
}
const dnsServer = servers[domain.tries % servers.length]!;
resolver.setServers([dnsServer]);
logger.debug(
`Using DNS server ${dnsServer} for domain ${domain.baseDomain} (try ${domain.tries})`
);
// Get all DNS records for this domain
const records: DnsRecord[] = await db
.select()
.from(dnsRecords)
.where(eq(dnsRecords.domainId, domain.domainId));
if (records.length === 0) {
logger.warn(`No DNS records found for domain ${domain.baseDomain}`);
return false;
}
if (!forceRecheck && records.every((r) => r.verified)) {
logger.info(
`All DNS records already verified for domain ${domain.baseDomain}`
);
return true;
}
logger.info(
`Validating ${records.length} DNS records for domain ${domain.baseDomain}`
);
// Collect the full set of expected NS values for this domain so we can
// detect extra records that are present in DNS but not in our DB.
const expectedNsValues = new Set<string>(
records.filter((r) => r.recordType === "NS").map((r) => r.value)
);
// Cache resolved NS records across iterations — there will be 3 NS
// records in the DB and we don't need to hit the upstream server 3 times.
let previousNs: string[] | null = null;
for (const record of records) {
// Skip already verified records, unless a live recheck was requested
if (record.verified && !forceRecheck) {
continue;
}
let isValid = false;
try {
if (record.recordType === "NS") {
let nsRecords: string[] | null = previousNs;
if (!nsRecords) {
nsRecords = await resolver.resolveNs(
record.baseDomain || domain.baseDomain
);
}
logger.info(
`NS records for ${
record.baseDomain || domain.baseDomain
}:`,
nsRecords
);
// Check if this expected NS value is present in the live records.
// A stale/legacy expected value (e.g. left over from a
// nameserver rebrand) is also accepted as long as the live
// records resolve to some other known-valid nameserver —
// the specific literal hostname stored per-domain isn't
// meaningful once it's a recognized alias.
isValid = nsRecords.some((ns) => ns === record.value);
previousNs = nsRecords;
} else if (record.recordType === "CNAME") {
const cnameRecords = await resolver.resolveCname(
record.baseDomain || domain.baseDomain
);
logger.info(
`CNAME records for ${
record.baseDomain || domain.baseDomain
}:`,
cnameRecords
);
// Check if the CNAME record matches the expected value
isValid =
cnameRecords.length === 1 &&
cnameRecords[0] === record.value;
} else if (record.recordType === "TXT") {
const txtRecords = await resolver.resolveTxt(
record.baseDomain || domain.baseDomain
);
logger.info(
`TXT records for ${
record.baseDomain || domain.baseDomain
}:`,
txtRecords
);
// TXT records come as an array of arrays, flatten and check
const flatTxtRecords = txtRecords.flat();
isValid = flatTxtRecords.includes(record.value);
} else if (record.recordType === "A") {
const aRecords = await resolver.resolve4(
record.baseDomain || domain.baseDomain
);
logger.info(
`A records for ${
record.baseDomain || domain.baseDomain
}:`,
aRecords
);
// Check if the A record matches the expected value
isValid = aRecords.includes(record.value);
} else {
logger.warn(
`Unsupported record type: ${record.recordType}`
);
continue;
}
} catch (error) {
isValid = false;
logger.debug(
`Did not resolve ${record.recordType} record for ${
record.baseDomain || domain.baseDomain
}:`,
error
);
}
// Update the individual record verification status. Runs for
// both a mismatched value and a failed/thrown DNS lookup, so a
// previously-verified record that stops resolving (e.g. NXDOMAIN
// after NS delegation is dropped) gets downgraded instead of
// leaving stale `verified: true` state behind.
if (isValid) {
await db
.update(dnsRecords)
.set({ verified: true })
.where(eq(dnsRecords.id, record.id));
logger.info(
`DNS record ${record.id} (${record.recordType}) for ${
record.baseDomain || domain.baseDomain
} verified successfully`
);
} else {
if (record.verified) {
await db
.update(dnsRecords)
.set({ verified: false })
.where(eq(dnsRecords.id, record.id));
}
logger.debug(
`DNS record ${record.id} (${record.recordType}) for ${
record.baseDomain || domain.baseDomain
} does not match expected value: ${record.value}`
);
}
}
// --- Extra NS record check ---
// If we resolved NS records during this pass, verify that the live DNS
// has no nameservers beyond the ones we expect. Individual records may
// already be marked verified above, but we must block full domain
// verification until the extra records are removed.
if (previousNs !== null && expectedNsValues.size > 0) {
const extraNsRecords = previousNs.filter(
(ns) => !expectedNsValues.has(ns)
);
if (extraNsRecords.length > 0) {
const errorMessage = `Extra NS records found that are not expected: ${extraNsRecords.join(", ")}. Remove these nameservers to complete domain verification.`;
await db
.update(domains)
.set({ errorMessage })
.where(eq(domains.domainId, domain.domainId));
logger.warn(
`Domain ${domain.baseDomain} has extra NS records that prevent verification: ${extraNsRecords.join(", ")}`
);
return false;
}
// No extras — clear any stale error that was previously written
await db
.update(domains)
.set({ errorMessage: null })
.where(eq(domains.domainId, domain.domainId));
}
// Check if all records are now verified
const updatedRecords: DnsRecord[] = await db
.select()
.from(dnsRecords)
.where(eq(dnsRecords.domainId, domain.domainId));
const allRecordsVerified = updatedRecords.every((r) => r.verified);
logger.info(
`Domain ${domain.baseDomain}: ${
updatedRecords.filter((r) => r.verified).length
}/${updatedRecords.length} records verified`
);
return allRecordsVerified;
}
}
export const dnsValidator = new DNSValidator();