fix(discovery): decode dns-sd escaped UTF-8

This commit is contained in:
Peter Steinberger
2026-01-09 14:56:01 +01:00
parent 02aeff8efc
commit 944f15e401
2 changed files with 120 additions and 8 deletions

View File

@@ -7,6 +7,7 @@ import { WIDE_AREA_DISCOVERY_DOMAIN } from "./widearea-dns.js";
describe("bonjour-discovery", () => {
it("discovers beacons on darwin across local + wide-area domains", async () => {
const calls: Array<{ argv: string[]; timeoutMs: number }> = [];
const studioInstance = "Peters Mac Studio Bridge";
const run = vi.fn(
async (argv: string[], options: { timeoutMs: number }) => {
@@ -17,7 +18,7 @@ describe("bonjour-discovery", () => {
if (domain === "local.") {
return {
stdout: [
"Add 2 3 local. _clawdbot-bridge._tcp. Studio Bridge",
"Add 2 3 local. _clawdbot-bridge._tcp. Peter\\226\\128\\153s Mac Studio Bridge",
"Add 2 3 local. _clawdbot-bridge._tcp. Laptop Bridge",
"",
].join("\n"),
@@ -44,16 +45,20 @@ describe("bonjour-discovery", () => {
if (argv[0] === "dns-sd" && argv[1] === "-L") {
const instance = argv[2] ?? "";
const host =
instance === "Studio Bridge"
instance === studioInstance
? "studio.local"
: instance === "Laptop Bridge"
? "laptop.local"
: "tailnet.local";
const tailnetDns =
instance === "Tailnet Bridge" ? "studio.tailnet.ts.net" : "";
const displayName =
instance === studioInstance
? "Peters\\032Mac\\032Studio"
: instance.replace(" Bridge", "");
const txtParts = [
"txtvers=1",
`displayName=${instance.replace(" Bridge", "")}`,
`displayName=${displayName}`,
`lanHost=${host}`,
"gatewayPort=18789",
"bridgePort=18790",
@@ -85,6 +90,14 @@ describe("bonjour-discovery", () => {
});
expect(beacons).toHaveLength(3);
expect(beacons).toEqual(
expect.arrayContaining([
expect.objectContaining({
instanceName: studioInstance,
displayName: "Peters Mac Studio",
}),
]),
);
expect(beacons.map((b) => b.domain)).toEqual(
expect.arrayContaining(["local.", WIDE_AREA_DISCOVERY_DOMAIN]),
);
@@ -98,6 +111,68 @@ describe("bonjour-discovery", () => {
expect(browseCalls.every((c) => c.timeoutMs === 1234)).toBe(true);
});
it("decodes dns-sd octal escapes in TXT displayName", async () => {
const run = vi.fn(
async (argv: string[], options: { timeoutMs: number }) => {
if (options.timeoutMs < 0) throw new Error("invalid timeout");
const domain = argv[3] ?? "";
if (argv[0] === "dns-sd" && argv[1] === "-B" && domain === "local.") {
return {
stdout: [
"Add 2 3 local. _clawdbot-bridge._tcp. Studio Bridge",
"",
].join("\n"),
stderr: "",
code: 0,
signal: null,
killed: false,
};
}
if (argv[0] === "dns-sd" && argv[1] === "-L") {
return {
stdout: [
"Studio Bridge._clawdbot-bridge._tcp. can be reached at studio.local:18790",
"txtvers=1 displayName=Peter\\226\\128\\153s\\032Mac\\032Studio lanHost=studio.local gatewayPort=18789 bridgePort=18790 sshPort=22",
"",
].join("\n"),
stderr: "",
code: 0,
signal: null,
killed: false,
};
}
return {
stdout: "",
stderr: "",
code: 0,
signal: null,
killed: false,
};
},
);
const beacons = await discoverGatewayBeacons({
platform: "darwin",
timeoutMs: 800,
domains: ["local."],
run: run as unknown as typeof runCommandWithTimeout,
});
expect(beacons).toEqual([
expect.objectContaining({
domain: "local.",
instanceName: "Studio Bridge",
displayName: "Peters Mac Studio",
txt: expect.objectContaining({
displayName: "Peters Mac Studio",
}),
}),
]);
});
it("falls back to tailnet DNS probing for wide-area when split DNS is not configured", async () => {
const calls: Array<{ argv: string[]; timeoutMs: number }> = [];

View File

@@ -27,6 +27,42 @@ const DEFAULT_TIMEOUT_MS = 2000;
const DEFAULT_DOMAINS = ["local.", WIDE_AREA_DISCOVERY_DOMAIN] as const;
function decodeDnsSdEscapes(value: string): string {
let decoded = false;
const bytes: number[] = [];
let pending = "";
const flush = () => {
if (!pending) return;
bytes.push(...Buffer.from(pending, "utf8"));
pending = "";
};
for (let i = 0; i < value.length; i += 1) {
const ch = value[i] ?? "";
if (ch === "\\" && i + 3 < value.length) {
const escaped = value.slice(i + 1, i + 4);
if (/^[0-9]{3}$/.test(escaped)) {
const byte = Number.parseInt(escaped, 10);
if (!Number.isFinite(byte) || byte < 0 || byte > 255) {
pending += ch;
continue;
}
flush();
bytes.push(byte);
decoded = true;
i += 3;
continue;
}
}
pending += ch;
}
if (!decoded) return value;
flush();
return Buffer.from(bytes).toString("utf8");
}
function isTailnetIPv4(address: string): boolean {
const parts = address.split(".");
if (parts.length !== 4) return false;
@@ -119,7 +155,7 @@ function parseTxtTokens(tokens: string[]): Record<string, string> {
const idx = token.indexOf("=");
if (idx <= 0) continue;
const key = token.slice(0, idx).trim();
const value = token.slice(idx + 1).trim();
const value = decodeDnsSdEscapes(token.slice(idx + 1).trim());
if (!key) continue;
txt[key] = value;
}
@@ -134,7 +170,7 @@ function parseDnsSdBrowse(stdout: string): string[] {
if (!line.includes("Add")) continue;
const match = line.match(/_clawdbot-bridge\._tcp\.?\s+(.+)$/);
if (match?.[1]) {
instances.add(match[1].trim());
instances.add(decodeDnsSdEscapes(match[1].trim()));
}
}
return Array.from(instances.values());
@@ -144,7 +180,8 @@ function parseDnsSdResolve(
stdout: string,
instanceName: string,
): GatewayBonjourBeacon | null {
const beacon: GatewayBonjourBeacon = { instanceName };
const decodedInstanceName = decodeDnsSdEscapes(instanceName);
const beacon: GatewayBonjourBeacon = { instanceName: decodedInstanceName };
let txt: Record<string, string> = {};
for (const raw of stdout.split("\n")) {
const line = raw.trim();
@@ -168,7 +205,7 @@ function parseDnsSdResolve(
}
beacon.txt = Object.keys(txt).length ? txt : undefined;
if (txt.displayName) beacon.displayName = txt.displayName;
if (txt.displayName) beacon.displayName = decodeDnsSdEscapes(txt.displayName);
if (txt.lanHost) beacon.lanHost = txt.lanHost;
if (txt.tailnetDns) beacon.tailnetDns = txt.tailnetDns;
if (txt.cliPath) beacon.cliPath = txt.cliPath;
@@ -176,7 +213,7 @@ function parseDnsSdResolve(
beacon.gatewayPort = parseIntOrNull(txt.gatewayPort);
beacon.sshPort = parseIntOrNull(txt.sshPort);
if (!beacon.displayName) beacon.displayName = instanceName;
if (!beacon.displayName) beacon.displayName = decodedInstanceName;
return beacon;
}