hedgedoc/backend/src/sessions/session.service.ts
Yannick Bungers f362d27d3f Move session entity to sessions folder
Signed-off-by: Yannick Bungers <git@innay.de>
2023-07-06 12:07:44 +02:00

107 lines
3.8 KiB
TypeScript

/*
* SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
*
* SPDX-License-Identifier: AGPL-3.0-only
*/
import { Optional } from '@mrdrogdrog/optional';
import { Inject, Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { TypeormStore } from 'connect-typeorm';
import { parse as parseCookie } from 'cookie';
import { unsign } from 'cookie-signature';
import { IncomingMessage } from 'http';
import { Repository } from 'typeorm';
import authConfiguration, { AuthConfig } from '../config/auth.config';
import { DatabaseType } from '../config/database-type.enum';
import databaseConfiguration, {
DatabaseConfig,
} from '../config/database.config';
import { HEDGEDOC_SESSION } from '../utils/session';
import { Username } from '../utils/username';
import { Session } from './session.entity';
export interface SessionState {
cookie: unknown;
username?: Username;
authProvider: string;
}
/**
* Finds {@link Session sessions} by session id and verifies session cookies.
*/
@Injectable()
export class SessionService {
private static readonly sessionCookieContentRegex = /^s:(([^.]+)\.(.+))$/;
private readonly typeormStore: TypeormStore;
constructor(
@InjectRepository(Session) private sessionRepository: Repository<Session>,
@Inject(databaseConfiguration.KEY)
private dbConfig: DatabaseConfig,
@Inject(authConfiguration.KEY)
private authConfig: AuthConfig,
) {
this.typeormStore = new TypeormStore({
cleanupLimit: 2,
limitSubquery: dbConfig.type !== DatabaseType.MARIADB,
}).connect(sessionRepository);
}
getTypeormStore(): TypeormStore {
return this.typeormStore;
}
/**
* Finds the username of the user that own the given session id.
*
* @async
* @param sessionId The session id for which the owning user should be found
* @return A Promise that either resolves with the username or rejects with an error
*/
fetchUsernameForSessionId(sessionId: string): Promise<Username | undefined> {
return new Promise((resolve, reject) => {
this.typeormStore.get(sessionId, (error?: Error, result?: SessionState) =>
error || !result ? reject(error) : resolve(result.username as Username),
);
});
}
/**
* Extracts the hedgedoc session cookie from the given {@link IncomingMessage request} and checks if the signature is correct.
*
* @param request The http request that contains a session cookie
* @return An {@link Optional optional} that either contains the extracted session id or is empty if no session cookie has been found
* @throws Error if the cookie has been found but the content is malformed
* @throws Error if the cookie has been found but the content isn't signed
*/
extractSessionIdFromRequest(request: IncomingMessage): Optional<string> {
return Optional.ofNullable(request.headers?.cookie)
.map((cookieHeader) => parseCookie(cookieHeader)[HEDGEDOC_SESSION])
.map((rawCookie) =>
this.extractVerifiedSessionIdFromCookieContent(rawCookie),
);
}
/**
* Parses the given session cookie content and extracts the session id.
*
* @param rawCookie The cookie to parse
* @return The extracted session id
* @throws Error if the cookie has been found but the content is malformed
* @throws Error if the cookie has been found but the content isn't signed
*/
private extractVerifiedSessionIdFromCookieContent(rawCookie: string): string {
const parsedCookie =
SessionService.sessionCookieContentRegex.exec(rawCookie);
if (parsedCookie === null) {
throw new Error(
`cookie "${HEDGEDOC_SESSION}" doesn't look like a signed session cookie`,
);
}
if (unsign(parsedCookie[1], this.authConfig.session.secret) === false) {
throw new Error(`signature of cookie "${HEDGEDOC_SESSION}" isn't valid.`);
}
return parsedCookie[2];
}
}