cvsa/packages/backend/middleware/captcha.ts

112 lines
3.3 KiB
TypeScript

import { Context, Next } from "hono";
import { ErrorResponse } from "src/schema";
import { SlidingWindow } from "@core/mq/slidingWindow.ts";
import { getCaptchaConfigMaxDuration, getCurrentCaptchaDifficulty } from "@/lib/auth/captchaDifficulty.ts";
import { sqlCred } from "@core/db/dbNew.ts";
import { redis } from "@core/db/redis.ts";
import { verify } from 'hono/jwt';
import { JwtTokenInvalid, JwtTokenExpired } from "hono/utils/jwt/types";
import { getJWTsecret } from "@/lib/auth/getJWTsecret.ts";
import { lockManager } from "@core/mq/lockManager.ts";
import { object, string, number, ValidationError } from "yup";
const tokenSchema = object({
exp: number().integer(),
id: string().length(6),
difficulty: number().integer().moreThan(0)
});
export const captchaMiddleware = async (c: Context, next: Next) => {
const authHeader = c.req.header("Authorization");
if (!authHeader) {
const response: ErrorResponse = {
message: "'Authorization' header is missing.",
code: "UNAUTHORIZED"
};
return c.json<ErrorResponse>(response, 401);
}
const authIsBearer = authHeader.startsWith("Bearer ");
if (!authIsBearer || authHeader.length < 8) {
const response: ErrorResponse = {
message: "'Authorization' header is invalid.",
code: "INVALID_HEADER"
};
return c.json<ErrorResponse>(response, 400);
}
const [r, err] = getJWTsecret();
if (err) {
return c.json<ErrorResponse>(r as ErrorResponse, 500);
}
const jwtSecret = r as string;
const token = authHeader.substring(7);
const path = c.req.path;
const method = c.req.method;
const route = `${method}-${path}`;
const requiredDifficulty = await getCurrentCaptchaDifficulty(sqlCred, route);
try {
const decodedPayload = await verify(token, jwtSecret);
const payload = await tokenSchema.validate(decodedPayload);
const difficulty = payload.difficulty;
const tokenID = payload.id;
const consumed = await lockManager.isLocked(tokenID);
if (consumed) {
const response: ErrorResponse = {
message: "Token has already been used.",
code: "INVALID_CREDENTIALS"
};
return c.json<ErrorResponse>(response, 401);
}
if (difficulty < requiredDifficulty) {
const response: ErrorResponse = {
message: "Token to weak.",
code: "UNAUTHORIZED"
};
return c.json<ErrorResponse>(response, 401);
}
const EXPIRE_FIVE_MINUTES = 300;
await lockManager.acquireLock(tokenID, EXPIRE_FIVE_MINUTES);
}
catch (e) {
if (e instanceof JwtTokenInvalid) {
const response: ErrorResponse = {
message: "Failed to verify the token.",
code: "INVALID_CREDENTIALS"
};
return c.json<ErrorResponse>(response, 400);
}
else if (e instanceof JwtTokenExpired) {
const response: ErrorResponse = {
message: "Token expired.",
code: "INVALID_CREDENTIALS"
};
return c.json<ErrorResponse>(response, 400);
}
else if (e instanceof ValidationError) {
const response: ErrorResponse = {
code: "INVALID_QUERY_PARAMS",
message: "Invalid query parameters",
errors: e.errors
};
return c.json<ErrorResponse>(response, 400);
}
else {
const response: ErrorResponse = {
message: "Unknown error.",
code: "UNKNOWN_ERROR"
};
return c.json<ErrorResponse>(response, 500);
}
}
const duration = await getCaptchaConfigMaxDuration(sqlCred, route);
const window = new SlidingWindow(redis, duration);
await window.event(`captcha-${route}`);
await next();
};