Sergey Budaev

Feb 06, 2023

XMPP: en ideell direktemeldingssystem for et familie

Forskjellige meldingssystemer ble populær de siste tiårene. Den meste kjente eksempler er Whatsapp, Facebook Messenger, Snapchat eller Discord. Mange bruker dem uten å tenke bare fordi de ser praktiske ut og er gratis. Kostnadene er imidlertid alvorlig: den er personvernkatastrofe. Brukere har ingen egenkontroll, så eieren kan endre alle funksjoner uten at brukerne vilje. Disse tjenstene (platformene) er laget og fullstendig kontrollert av store monopoler fokuserte på å suge alle slags av brukerdata. Personvernkostnaden til store kommersielle direktmeldingssystemer av er mye høyere enn brukervennligheten. De er bevisst laget for å være gjensidig uforenlige. En bruker av Whatsapp kan ikke sende en melding til noen på Telegram eller Facebook. Bare se for deg at du hadde Telenor men kunne ikke sende sms til noen på Telia, kun til sin eget system Telenor. Eller se hvis du kunne ikke sende en epost fra Gmail til Yahoo. Det er helt dumt.

Nå, blant de populære systemene er det bare epost det eneste systemet på internett som har ikke vært monopolisert. Og det er fortsett fordi epost ikke er en plattform (eller 'ecosystem'), men åpen og federert protokoll etter eget design. Alle kan konfigurere og kjøre egen mailserver og meldinger skal sendes mellom evt. Alle kan velge mellom mange epost apper. Alle kan legge til ytterligere funksjonalitet, slik at ende-til-ende kryptering, men interoperabilitet opprettholdes.

Protokoll betyr et sett med regler og konvensjoner for interoperabilitet, ikke et enkelt komplett produkt.

xmpp logo

Men, det finnes en direktemeldingssystem som er like enkel å bruke som Whatsapp, men mangler de fleste av problemene. Faktisk, er det XMPP. Det er en åpen og federert protokoller som epost. Alle kan ha egen server, så kan ha kontakt med noen på alle serverer som helst, akkurat som epost eller mobil. I tillegg, kan alle også velge mellom ulike app etter vilje: foretrekker du funksjonalitet, eller skjønnhet eller bare det å være veldig lett... Det finnes også flere XMPP serverer programvare å velge mellom, de fleste er gratis og åpen kildekode. Med XMPP kan du få alt: direktemeldinger, filer, tale, video, gruppechat, flere enheter. Det er også flere typer av ende-til-ende kryptering (OMEMO, GPG, OTR) og mye mer. Det finnes enda en XMPP-basert sosialnettverk: Movim.

XMPP er ikke alene. Det finnes også en alternativ åpen og federert protokoll: Matrix. Men sammenlignet med XMPP, har den flere mangler: (a) problemer med personvern (selv om mange ikke bryr seg om det), (b) alvorlige ytelsesproblemer: mens XMPP fungerer fint selv på den minste og billigste VPS, Matrix server krever mange gigabyter med RAM og stor diskplass, på denne grunn er det dyrere i drift, også krever Matrix mye mer oppmerksomhet (f.eks. se her). Det kan være berettiget i bedrifts- eller stororganisasjonsbruk, men ikke i hjemmebruk.

Så XMPP er ideell for å lage et helt privat kommunikasjonssystem for et familie. Du trenger bare dette: (a) en server: billigste VPS eller enda en Rasberry Pi boks vil fungere fint (f.eks ejabberd skal støtte hundrevis brukere med dette nivå); (b) server programvare som kjøres alt: sjekke ut flere og velge selv, de mest populære er ejabberd og Prosody; (c) domenenavn slik at brukere kan konnektere til: domenenavn er også en del av brukernavn, som i epost, f. eks alexander@johansson.me (enkelt DNS oppsett trenges for å støtte tale og video); (d) hver bruker kan velge hvilken klientapp som skal brukes (f. eks Monal eller Siskin IM på iPhone). Og det er det.

Nå må serveren konfigureres. Så kontrollerer du systemet fullt ut! Du kan registrere så mange brukere at du trenger, men for en familieserver anbefaler jeg ikke å tillate åpen registrering av alle som helst. For eksempel du kan registrere flere kontoer for en enkelt bruker hvis nyttig (å bruke med forskjellige formål). Ingen mobilnummer kreves: f.eks. trenger du ikke fem SIM-korter for fem brukere, faktisk ingen er nødvendig. Det også anbefales å konfigurere ‘Shared roster group’ (delt brukerliste) for å unngå å legge til familiekontakter manuelt for alle familiemedlemmer. Ende-til-ende kryptering er ikke avgjørende for din egen private server fordi transportkryptering (TLS) brukes alltid; men det er lettere å konfigurere hvis du bruker flere enheter (mobil, nettbrett, desktop, laptop, web-basert). Men det er bedre og sikrere å bruke ende-til-ende kryptering til å kommunisere med noen på andre offentlige servere.

Og nå, når flere grupper har sine egne private servere, kan de kommunisere fritt og sikkert. For eksempel, det er nå lett for pappa@johansson.me å sende melding (eller video-ringe) til mattias@johansson.me (samme familier og på samme privat server) eller til en venn john@dowfamily.info eller enda alle som bruker hundrevis av åpne gratis offentlige serverer f. eks maria@jabber.no (på Jabber Norge), christian@jabber.de, oyvindharaldsson@tigase.org eller nikolaibode@riseup.net.

Federated network

Se her for litt mer informasjon om XMPP.

Lenker

Apr 22, 2022

Goodbye Gmail

The old good email remains the most critical digital communication tool. What makes the venerable email so useful and sustainable over the long time is its openness and standardization. Email is radically different from the modern "apps" which integrate all pieces of technology--the server, the client, and the protocol--by a single monopolist provider. With email, we are free to choose the server (provider) and client with any combination. It provides enormous flexibility, added privacy and security. Indeed, the provider does not control my client and cannot add backdoors; there is no monoculture of client software with all the related security risks (any security vulnerability is global). Email is one of the few pieces of technology that is very resistant against internet censorship. Repressive state can easily block a web site and even force an app store to remove an app (as the Navalny's "Smart Voting"). Also, an app store can delete it for any other bizarre reason. But it is much more difficult to block a mailing list: it is easy to redeploy and recreate it on a different server (without the users even noticing anything). Furthermore, The user can easily create several different email-based identities (e.g. a separate one for politically sensitive activity) which adds anonymity. And anonymity means physical security in some countries.

It is not surprising that many internet services use the email address to register users, authenticate, restore password and other similar purposes. Open, standardized and decentralized email is one of the most critical technology everything else depends on. After all, the flexibility offered by the email technology--the freedom to choose all pieces (provider, client etc.) is just very very handy, at least for an advanced user (you can add new features on top of what the provider realized, even against the provider's will--isn't it convenient?).

The whole email technology is build around open protocols rather than a centralized platform. This facilitates competition, makes for better and fairer service and reduce possible impacts of malicious monopolists (Masnick, 2019).

Google's Gmail has long been one of the main pillars of email, millions used to rely upon every day. We should praise Google for popularising email as the basic mainstream technology among the masses. I started using Gmail many years ago when it was in its "beta" and available only by invitation. At that time Gmail openness and unrestricted nature was just blazing. The web interface was lightweight and not really cluttered with ugly banners, unlike other email providers. There were ads but they were small and unobtrusive. Gmail had long supported all the basic protocols (POP, IMAP, SMTP) that allowed to use any standard compliant client software, and that was available for free (some other providers were more greedy and allowed this only on paid plans). Google's POP, IMAP and SMTP implementations have been (and still remain!) quite idiosyncratic, incomplete and not really standard-compliant which caused various glitches (e.g. message deletion and default sorting are weird, I always hated Gmail's labels). But this was bearable.

The serious privacy problems and threats of Gmail, such as user email scanning for context-specific advertising (until 2017) or AI tool which could provide access to some pieces of data to third-party developers. That is nearly a disaster that cannot be fixed because spying on the user's data is at the heart of Google's business model. But who cares as long as it is free! I have long been using and promoting PGP encryption which could fix many of the privacy (and security) problems. Yes, PGP is crucial for individuals and businesses and yes, a motivated user can encrypt.

Gmail still remained free and relatively open while an alternative of deploying private email server is time-consuming and tedious (e.g. ensuring that emails from a tiny private server don't end up in spam folders of intended recipients). I used to pay with some of my privacy to get the usability and stability of Gmail.

But over time I became increasingly concerned about the clear trend taken by Google to make the open email more and more difficult to use outside of the Google monopolistic ecosystem. There are signs of the famous embrace, extend, and extinguish strategy. Gmail API is featureful and powerful... but only if you really need the complexity and like to play with the Google rules. If you don't like to see ads, for example, and for this use a standard IMAP mail client of your choice, your must suffer. If you need full PGP support on a mobile client, never offered by Google, you are out of luck and have to use an IMAP-based mobile app like Android K-9 Mail that requires sacrificing some usability.

Google tends to draw its users by all means into its browser, its own apps and APIs to get more user's private data and show ads. For that matter, Google's security usability has become just terrible. The intrusive access-blocks when a mobile user with an IMAP client moves across IP addresses can drive anyone crazy... Access can be blocked even if the user switches just to the next IP address within the same provider's IP pool.

Google security alert

I have to use VPN with fixed IP address to avoid these stupid blocks!

To help keep your account secure, Google will no longer support the use of third-party apps or devices which ask you to sign in to your Google Account using only your username and password. Instead, you’ll need to sign in using Sign in with Google.

The Google's insistence on rather complicated and heavyweight OAuth2 mechanism for basic email client access (remember, most email programs do not require you to enter your password every time, diminishing the risk of phishing) is understandable only as a means to limit all uncontrollable third-party clients. Yes, OAuth2 is logical for complex workflows of data access delegation across multiple web-based services with different login/password combinations (the "Auth" stands for authorization, not authentication). Whenever I need access to my own emails I need to authenticate my identity granting full access. But isn't OAuth2 client secret kept on the device just as the username/password combination? Yet, limiting the (power) users access to their own data provides just an illusion of security at a large cost to usability and compatibility.

The Google's move to OAuth2 authorization seem to point that the Gmail-hosted emails do not belong to me any more. My emails are now owned by Google, who just "authorizes" (delegates) me access to some of the data without trusting me. This is not what I need from my private communication. Does Google pretend to "zero-trust" any third-party apps? Maybe it doesn't trust its users (the owners of their data), assuming they are all idiots?

If you think your users are idiots, only idiots will use it [your service]. --- Linus Torvalds

And there is another side effect: as Google increasingly deployed more and more heavyweight frameworks and technologies, Gmail became very sluggish and bloated. It is cluttered and confusing, especially to those who don't use it often enough to remember all the idiosyncrasies. And it's still poorly adaptable to the user's needs. How can I get a fixed-width font for my plain text message? Where is my favourite basic (and very fast) HTML web interface?

Enough is enough. I now go away from Gmail, and primarily not because of big privacy concerns (which is quite expectable) but because of deteriorating usability and growing incompatibility. It looks like the people at Google have forgotten their old motto "Don't be evil." While I have been paying Google with my privacy currency in the past to get functionality and usability, the benefits of Gmail continuously went lower and now reached an unprofitable level.

Migadu is my choice

There are many hosted email providers, some are focused on privacy and security. For example, Protonmail is a fantastic project that makes it nearly trivial to use PGP even for an uninitiated. But its drawbacks are that it is non-standard and has too high publicity making it quite undesirable in certain authoritarian countries. Simply said, if you use Protonmail in some countries you may be suspected; Protonmail can be blocked by the authorities, and worse still, blocked in quite idiosyncratic way. Some services may also reject registration using this service.

What I have finally chosen is Migadu. It is not yet another standard email hosting provider. It is a domain-based service. Once you have got your own domain name (domains are now cheap), you can make your own email service for your domain. That simple. This makes it super useful for companies, families, groups and NGOs without large budgets. For a reasonable price you get nearly your own mail server with many configurable features (any custom mailboxes, aliases, forwarding, regexp, webmail, etc.) but without the need to maintain all this complex system.

If you have a web site, you necessarily get a domain name for it. Now it's easy to get your own email identity. True that some hosting providers also do host email. But if you decide to switch to a different hosting it will create a trouble: you need to move also email and this fact strongly limits your next choice. Having a completely indpendent email system for your existing domain avoids such hoster lock-in and makes life much easier.

By the way, the Migadu standard webmail interface is sleek and very simple. Looks modern but lightweight and quite fast. No bloat whatsoever, only the most crucial functionality. I am not big fan of web-based email, but use it from time to time. And there is even some very basic support for PGP! (But remember that web-based PGP is not a very secure solution.)

I found the mail server configuration (including more esoteric stuff like DNS setup and DKIM signatures) very easy. In my view you do not need an IT degree to configure your email server with full functionality. I like the admin panel, it is minimalist and easy to use, no stupid and distracting visual effects. And Migadu is advertised as fully open standard compliant service without proprietary glitches and limitations. So any standard (open source or closed source) software is very likely to be fully usable. This freedom is very important. And they are also clear and honest about the limitations and drawbacks.

Finally, goodbye Gmail.


PS: Disclaimer: I have no links with Migadu.

This post is also published on Substack and Medium