Files
caddy-proxy-manager/app/api/auth/[...nextauth]/route.ts
2026-02-25 18:38:25 +01:00

98 lines
3.1 KiB
TypeScript

import { NextResponse } from "next/server";
import type { NextRequest } from "next/server";
import { handlers } from "@/src/lib/auth";
import { isRateLimited, registerFailedAttempt, resetAttempts } from "@/src/lib/rate-limit";
export const dynamic = 'force-dynamic';
export const { GET } = handlers;
function getClientIp(request: NextRequest): string {
// Get client IP from headers
// In production, ensure your reverse proxy (Caddy) sets these headers correctly
const forwarded = request.headers.get("x-forwarded-for");
if (forwarded) {
const parts = forwarded.split(",");
return parts[parts.length - 1]?.trim() || "unknown";
}
const real = request.headers.get("x-real-ip");
if (real) {
return real.trim();
}
return "unknown";
}
function buildRateLimitKey(ip: string, username: string) {
const normalizedUsername = username.trim().toLowerCase() || "unknown";
return `login:${ip}:${normalizedUsername}`;
}
function buildBlockedResponse(retryAfterMs?: number) {
const retryAfterSeconds = retryAfterMs ? Math.ceil(retryAfterMs / 1000) : 60;
const retryAfterMinutes = Math.max(1, Math.ceil(retryAfterSeconds / 60));
return NextResponse.json(
{
error: `Too many login attempts. Try again in about ${retryAfterMinutes} minute${retryAfterMinutes === 1 ? "" : "s"}.`
},
{
status: 429,
headers: {
"Retry-After": retryAfterSeconds.toString()
}
}
);
}
export async function POST(request: NextRequest) {
const formData = await request.clone().formData();
const username = String(formData.get("username") ?? "");
const ip = getClientIp(request);
const rateLimitKey = buildRateLimitKey(ip, username);
const limitation = isRateLimited(rateLimitKey);
if (limitation.blocked) {
return buildBlockedResponse(limitation.retryAfterMs);
}
const response = await handlers.POST(request);
// Determine success/failure by inspecting redirect destination, not status code.
// Auth.js returns 302 (direct form) or 200+JSON (X-Auth-Return-Redirect) on both
// success and failure — the error is signaled by the destination URL containing "error=".
const isFailure = await isAuthFailureResponse(response);
if (isFailure) {
const result = registerFailedAttempt(rateLimitKey);
if (result.blocked) {
return buildBlockedResponse(result.retryAfterMs);
}
} else {
resetAttempts(rateLimitKey);
}
return response;
}
async function isAuthFailureResponse(response: Response): Promise<boolean> {
// Redirect case: Auth.js sets Location header
const location = response.headers.get("location");
if (location) {
return location.includes("error=");
}
// JSON case (X-Auth-Return-Redirect: 1): body is {"url": "..."}
const contentType = response.headers.get("content-type") ?? "";
if (response.status === 200 && contentType.includes("application/json")) {
try {
const cloned = response.clone();
const body = await cloned.json() as { url?: string };
if (typeof body.url === "string") {
return body.url.includes("error=");
}
} catch {
// ignore parse errors
}
}
// Any 4xx/5xx is a failure
return response.status >= 400;
}