Blog - #2


Untrusted: The Issue with Decentralisation


Posted: 2022-06-29 (UTC+00:00)

Updated: 2022-06-29 (UTC+00:00)


Introduction

A recent trend is seeing people move towards decentralised services and
platforms. While this is reasonable and I can understand why they are doing
such a thing, they are seemingly doing it without thinking about the
possible consequences of doing so. The issue with decentralisation is
trust; there is no way to pin a key to a specific person, to ensure that
you are communicating with the same person you are supposed to be
communicating with. In this article, I will discuss some of the security
issues with the decentralised model.


Example: Messaging

When it comes to messaging your contacts on a centralised platform,
such as Twitter or Facebook, the keys are pinned to that user account,
using the user's password as the method of identification. This approach
makes it impossible to log in as a specific user without their password,
should it be strong enough to not be guessed, whether via personal guessing
or exhaustive search. The trust in this centralised model is the high
security these platforms have. It is extremely unlikely that anyone other
than a government would be able to access the accounts stored on such
platforms' servers, which makes the physical security trusted. As for
remote security, should a user's password be compromised, it can typically
be reset if the user can prove they are the owner of the account via some
form of identification; this is where the trust issue of decentralisation
occurs.


In the decentralised model, keys are kept on the users' devices, in their
possession. While this soveriegnty is welcomed, it indroduces a critical
flaw in the security of communicating with anyone via a decentralised
platform; should a user's device be lost, stolen, or otherwise compromised,
there is no way to know it happened and what the new keys really are, and
if the same user generated those keys. There is no centralised point where
anyone can go to check if the compromised user has updated their keys,
which means there must already have been at least one other secure channel
in place before the compromise occurred. Even if there was, the security
of endpoint devices, especially typical users, is much lower than a well
protected corporation's servers, making even those secure channels
questionable to trust. Should all secure channels be compromised, there is
literally no way to know if the person you are communicating with is the
real person or an imposter; there is no root of trust. This point is fatal;
game over. The only way to establish trust again would be to physically
meet and exchange keys.


Solution

I'll cut to the chase; there isn't a definitive solution. The best way
to handle this situation is to design your threat model and think about
your reasoning for avoiding centralised platforms. Is it lack of trust of
a specific company? Is it the possibility of centralised platforms going
offline? Only by thinking logically and tactically can you solve both the
issue of centralisation and decentralisation. Often, one size fits all is
never the correct approach, nor does it typically work.


In order to avoid the issue of loss of trust due to lack of root of trust,
all users' keys must be stored in a centralised location where all contacts
are able to go to in case of compromise or to periodically check the state
of keys and to see if they have changed. This centralised location requires
some sort of identification to ensure that the user changing their keys is
really the same person who initially signed up for the platform, using a
trust-on-first-use (TOFU) model, which isn't much different than what
today's centralised platforms are already doing; the only difference is who
is controlling the location; trust is still present and required.


In order to have a root of trust, I have posted my keys to my website,
which is protected by multiple layers of security:

1. I have provided identification to my domain name registrar, to ensure I
can access the website I rightfully own, should it be compromised, by
providing identification to the domain name registrar.

2. I have provided identification to my virtual private server host, to
ensure I can access the virtual private servers I rightfully rent, should
they be compromised, by providing identification to the virtual private
server host.

3. I have pinned my website to a globally trusted certificate authority,
Let's Encrypt, which is a trsuted party to manage TLS certificates and
ensure ownership of the domain when connecting to it.

4. I have enabled DNSSEC on my domain, so it is extremely difficult to
spoof my domain to make you believe you're connecting to it when you're
actually connecting to someone else's.
While not the most secure implementation a root of trust, but it is the
most secure implementation currently available to me. While the domain
name registrar or virtual private server host could tamper with my domain
and data, they are the most trustworthy parties available.
In its current form, decentralisation would make this impossible to
implement in any form.

Conclusion

Do not demand anonymity; demand privacy and control of your own data.
It is possible for someone else to hold your keys, without them taking
control of them and dictating what you can and cannot do (Twitter's
misinformation policy comes to mind). If a platform is not listening to
your or other people's concerns about how it is run, show those platforms
that you will not stand for it, and move to a different one. This may not
be ideal, but it's not different to moving from one decentralised platform
to another. Centralisation isn't what is evil, the people in control of the
platforms are what is potentially evil. Carefully, logically, and
tactically, choose who to trust. Decentralisation doesn't do much for trust
when you must still trust the operator of the decentralised platform, and
are still subject to the possibly draconian policies of that decentralised
platform. If government is what you are trying to avoid, there is no
denying it is feasibly impossible to avoid it; a government could always
take down the decentralised platform, forcing you to move to another,
and they could also take down the centralised key storage site mentioned
earlier in this article. A government is not something you can so easily
avoid. Decentralisation does not solve the government issue. In order to
live a happy, fun, and fulfilled life, while protecting yourself against
logical threats, there are only two words you must live by: Threat model.




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