3 SPEC - Spec not finalized
15 N&R. bring tor-spec up to date
16 N&R. make loglevels info,debug less noisy
17 N - Get win32 servers working, or find out why it isn't happening now.
19 ************************ For Post 0.0.9 *****************************
22 - niels's "did it fail because conn refused or timeout or what"
24 - if a version is later than the last in its series, but a version
25 in the next series is recommended, that doesn't mean it's bad.
26 - fix dfc/weasel's intro point bug
27 - support hostnames as well as IPs for authdirservers.
28 N - OS X package (and bundle?)
29 N - Make millisecond accuracy work on win32
30 - Make more configuration variables into CSVs.
31 - Once we have a trusted directory on port 80, stop falling back to
32 forbidden ports when fascistfirewall blocks all good dirservers.
33 - Convert man pages to pod, or whatever's right.
34 - Move to our new version system.
35 - Get more nodes running on 80 and 443.
36 - Get epic, aclu, etc running nodes.
37 - Start distributing an rpm with the new version scheme.
39 - cache .foo.exit names better, or differently, or not.
40 - teach connection_ap_handshake_socks_reply() about ipv6 and friends
41 so connection_ap_handshake_socks_resolved() doesn't also need
43 - when we haven't explicitly sent a socks reject, sending one in
44 connection_about_to_close_connection() fails because we never give
45 it a chance to flush. right answer is to do the socks reply manually
46 in each appropriate case, and then about-to-close-connection can
47 simply warn us if we forgot one.
48 - Solve the MSVC nuisance where __FILE__ contains the full path.
49 People are getting confused about why their errors are coming from
50 C:\Documents and Settings\Nick Mathewson\My Documents\src\tor .
51 - GPSLocation optional config string.
55 - Handle pools of waiting circuits better.
56 - Let more config options (e.g. ORPort) change dynamically.
57 - Write limiting; configurable token buckets.
58 - Only the top of a directory needs to be signed.
59 - Make sure logged information is 'safe'.
60 - make advertised_server_mode() ORs fetch dirs more often.
62 N - Clean up NT service code
63 - Work as an NT service; on system tray; etc.
64 - Win32 installer plus privoxy, sockscap/freecap, etc.
65 - controller should have 'getinfo' command to query about rephist,
66 about rendezvous status, etc.
67 - Implement If-Modified-Since for directories.
68 N - Handle rendezvousing with unverified nodes.
69 - Specify: Stick rendezvous point's key in INTRODUCE cell.
70 Bob should _always_ use key from INTRODUCE cell.
73 - Spec issue: if a resolve returns an IP4 and an IP6 address,
75 - christian grothoff's attack of infinite-length circuit.
76 the solution is to have a separate 'extend-data' cell type
77 which is used for the first N data cells, and only
78 extend-data cells can be extend requests.
79 . rename/rearrange functions for what file they're in
80 - tor should be able to have a pool of outgoing IP addresses
81 that it is able to rotate through. (maybe)
82 - hidserv offerers shouldn't need to define a SocksPort
83 * figure out what breaks for this, and do it.
84 - should retry exitpolicy end streams even if the end cell didn't
85 resolve the address for you
86 - Make it harder to circumvent bandwidth caps: look at number of bytes
87 sent across sockets, not number sent inside TLS stream.
88 - fix router_get_by_* functions so they can get ourselves too,
89 and audit everything to make sure rend and intro points are
90 just as likely to be us as not.
93 - Exit node caching: tie into squid or other caching web proxy.
95 - Website spiffying. Logo. Pictures.
96 - Configuration walk-through with screenshots of each step.
98 Deferred until needed:
99 - Do something to prevent spurious EXTEND cells from making middleman
100 nodes connect all over. Rate-limit failed connections, perhaps?
101 - Limit to 2 dir, 2 OR, N SOCKS connections per IP.
102 - Handle full buffers without totally borking
103 * do this eventually, no rush.
104 - Rate-limit OR and directory connections overall and per-IP and
106 - DoS protection: TLS puzzles, public key ops, bandwidth exhaustion.
107 - Have clients and dirservers preserve reputation info over
109 - round detected bandwidth up to nearest 10KB?
110 - client software not upload descriptor until:
111 - you've been running for an hour
112 - it's sufficiently satisfied with its bandwidth
113 - it decides it is reachable
114 - start counting again if your IP ever changes.
115 - never regenerate identity keys, for now.
116 - you can set a bit for not-being-an-OR.
117 * no need to do this yet. few people define their ORPort.
118 - authdirserver lists you as running iff:
119 - he can connect to you
120 - he has successfully extended to you
121 - you have sufficient mean-time-between-failures
122 * keep doing nothing for now.
123 - Include HTTP status messages in logging (see parse_http_response).
125 Blue sky or deferred indefinitely:
126 - Support egd or other non-OS-integrated strong entropy sources
127 - password protection for on-disk identity key
128 - Possible to get autoconf to easily install things into ~/.tor?
129 - server descriptor declares min log level, clients avoid servers
131 - put expiry date on onion-key, so people don't keep trying
132 old ones that they could know are expired?
133 - Add a notion of nickname->Pubkey binding that's not 'verification'
135 - Need a relay teardown cell, separate from one-way ends.
137 Big tasks that would demonstrate progress:
139 - Facility to automatically choose long-term helper nodes; perhaps
140 on by default for hidden services.
141 - patch privoxy and socks protocol to pass strings to the browser.
142 - patch tsocks with our current patches + gethostbyname, getpeername, etc.
143 - make freecap (or whichever) do what we want.
144 - scrubbing proxies for protocols other than http.
145 - Find an smtp proxy?
146 . Get socks4a support into Mozilla
147 N - Reverse DNS: specify and implement.
148 - figure out enclaves, e.g. so we know what to recommend that people
149 do, and so running a tor server on your website is helpful.
150 - Do enclaves for same IP only.
151 - Resolve first, then if IP is an OR, extend to him first.
152 - implement a trivial fun gui to demonstrate our control interface.
154 ************************ Roadmap for 2004-2005 **********************
156 Hard problems that need to be solved:
158 - Separating node discovery from routing.
159 - Arranging membership management for independence.
160 Sybil defenses without having a human bottleneck.
161 How to gather random sample of nodes.
162 How to handle nodelist recommendations.
163 Consider incremental switches: a p2p tor with only 50 users has
164 different anonymity properties than one with 10k users, and should
165 be treated differently.
166 - Measuring performance of other nodes. Measuring whether they're up.
167 - Choosing exit node by meta-data, e.g. country.
168 - Incentives to relay; incentives to exit.
169 - Allowing dissidents to relay through Tor clients.
170 - How to intercept, or not need to intercept, dns queries locally.
171 - Improved anonymity:
172 - Experiment with mid-latency systems. How do they impact usability,
173 how do they impact safety?
174 - Understand how powerful fingerprinting attacks are, and experiment
175 with ways to foil them (long-range padding?).
176 - Come up with practical approximations to picking entry and exit in
177 different routing zones.
178 - Find ideal churn rate for helper nodes; how safe is it?
179 - What info squeaks by Privoxy? Are other scrubbers better?
180 - Attacking freenet-gnunet/timing-delay-randomness-arguments.
181 - Is abandoning the circuit the only option when an extend fails, or
182 can we do something without impacting anonymity too much?
183 - Is exiting from the middle of the circuit always a bad idea?
185 Sample Publicity Landmarks:
187 - we have N servers / N users
188 - we have servers at epic and aclu and foo
189 - hidden services are robust and fast
190 - a more decentralized design
191 - tor win32 installer works
192 - win32 tray icon for end-users
193 - tor server works on win32
194 - win32 service for servers
195 - mac installer works
197 ***************************Future tasks:****************************
199 Rendezvous and hidden services:
201 - preemptively build and start rendezvous circs.
202 - preemptively build n-1 hops of intro circs?
203 - cannibalize general circs?
205 - standby/hotswap/redundant services.
206 - store stuff to disk? dirservers forget service descriptors when
207 they restart; nodes offering hidden services forget their chosen
208 intro points when they restart.
210 - auth mechanisms to let midpoint and bob selectively choose
213 - robust decentralized storage for hidden service descriptors.
215 - web proxy gateways to let normal people browse hidden services.
218 Relax clique assumptions.
219 Redesign how directories are handled.
220 - Resolve directory agreement somehow.
221 Find and remove bottlenecks
222 - Address linear searches on e.g. circuit and connection lists.
223 Reputation/memory system, so dirservers can measure people,
224 and so other people can verify their measurements.
225 - Need to measure via relay, so it's not distinguishable.
226 Let dissidents get to Tor servers via Tor users. ("Backbone model")
228 Make it more correct:
229 Handle half-open connections: right now we don't support all TCP
230 streams, at least according to the protocol. But we handle all that
231 we've seen in the wild.
234 Efficiency/speed/robustness:
235 Congestion control. Is our current design sufficient once we have heavy
236 use? Need to measure and tweak, or maybe overhaul.
237 Allow small cells and large cells on the same network?
238 Cell buffering and resending. This will allow us to handle broken
239 circuits as long as the endpoints don't break, plus will allow
240 connection (tls session key) rotation.
241 Implement Morphmix, so we can compare its behavior, complexity, etc.
242 Use cpuworker for more heavy lifting.
243 - Signing (and verifying) hidserv descriptors
244 - Signing (and verifying) intro/rend requests
245 - Signing (and verifying) router descriptors
246 - Signing (and verifying) directories
247 - Doing TLS handshake (this is very hard to separate out, though)
248 Buffer size pool: allocate a maximum size for all buffers, not
249 a maximum size for each buffer. So we don't have to give up as
250 quickly (and kill the thickpipe!) when there's congestion.
251 Other transport. HTTP, udp, rdp, airhook, etc. May have to do our own
252 link crypto, unless we can bully openssl into it.