[tor-dev] A modest proposal for a petname system in ideas/xxx-onion-nyms.txt
jacob at appelbaum.net
Sat Dec 17 01:14:52 UTC 2011
Arturo and I have discussed a possible petname system for tor2web that
would make it simple to remember hidden service names; it's not perfect,
it's not secure and it requires comment from the community. The basic
idea is to make it easy to deploy and see if anyone cares to use it.
Here's the proposal in url form:
Here's the proposal as text:
Title: .onion nym system
Author: Arturo FilastÃ², Jacob Appelbaum
Created: 17 December 2011
1. Intro and Motivation
The main issue that prohibits the wide scale adoption of .onion addressing
is the fact that they are not human memorable. While Zooko's triangle
you can only have at most two of "memorable", "secure" and "global" it is
possible to build a simple nym mechanism that relies on the current .onion
addressing system. We define a basic registration system generally
it's particual application to the tor2web network. This is a very
of petname system for applications such as tor2web.
These are the definitions of the actors involved in the process.
Beppe - The owner of the Tor Hidden Service
User - A random user of Tor/tor2web
v2cbb2l4lsnpio4q.onion - The .onion address that Beppe is interested
antani - The nym Beppe is interested in associating to
t2w - A tor2web node
This is the process through which Beppe is able to make a registration
for his chosen
3.1 General implementation
Beppe wishes to register "antani" to point to v2cbb2l4lsnpio4q.onion
so he creates a
a TCP service listening on his .onion will respond with the string
"reg antani" when
interrogated. The requester will make a lookup in his database to see if
"antani" is already registered. If it is not registered the "antani" <->
v2cbb2l4lsnpio4q.onion mapping is created. A timestamp is added to the
3.2 Tor2web implementation
Beppe creates a file called "onion.txt" containing the string "reg
antani" and uploads
it to the root of his web server. When User visits
t2w checks if his database contains a mapping with
v2cbb2l4lsnpio4q.onion, if it does
not, it requests the http://v2cbb2l4lsnpio4q.onion/onion.txt file.
If the file exists t2w reads it and extracts the "antani" string. A
lookup is made in
his database. If "antani" is not registered he creates a mapping
between "antani" and
v2cbb2l4lsnpio4q.onion. A timestamp is added to the database.
A nym will expire if either the HS goes offline for longer than a
threshold or if he explicitly requests removal of the association to that
particualr nym. This allows dynamic reallocation of nyms and avoids nym
4.1 Time delay
We define the default tiem threshold to be 30 days since the last
the time of expiry or anytime before, another request is made to
either the TCP
service or for the "onion.txt" file. If the Hidden Service is offline
the requested mapping has changed the mapping is removed or modified.
onion.txt is unchanged, the nym remains valid and the database timestamp
entry is updated.
The HS can specify the "release" string to delete the entry from the
To keep the database of registered nyms up to date in for many t2w
nodes, a synchronization
mechanism is required but currently out of scope for this document.
All the best,
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