path: root/TODO

PHASE #1: (Goal: settle key design questions)


Util:
* improve disk API [Nils] (Nils, is this done? -Christian)
* Windows: use events instead of pipes to signal select()s [Nils]
* only connect() sockets that are ready (select()) [Nils]
  [On W32, we need to select after calling socket before
   doing connect etc.]

TESTCASES WANTED:
For these functions, it would be nice if we had testcases ("make check")
that would cause them to be executed and check that they are working:
* gnunet-service-peerinfo:
  - change_host_trust / flush_trust 
  - remove_garbage / 
  - discard_hosts_helper / cron_clean_data_hosts
* gnunet-service-transport:
  - try_unvalidated_addresses
  - lookup_address_callback
  - lookup_hello_callback
  - plugin_env_lookup_address
  - notify_clients_disconnect
  - list_validated_addresses
  - cleanup_validation
  - disconnect_neighbour
  - handle_set_quota
* plugin_transport_tcp.c:
  - tcp_plugin_cancel
  - tcp_plugin_address_pretty_printer / append_port
  - tcp_plugin_set_receive_quota
  - delayed_done
* transport_api:
  - GNUNET_TRANSPORT_set_qutoa / send_set_quota
  - hello_wait_timeout 
  - transmit_ready
  - transmit_timeout
  - remove_from_any_list / remove_neighbour
  - GNUNET_TRANSPORT_notify_transmit_ready_cancel
* core_api:
  - timeout_request
  - solicit_traffic / copy_and_free
  - GNUNET_CORE_peer_configure / produce_configure_message
* gnunet-service-core:
  - update_window
  - find_client
  - handle_client_request_configure
  - set_key_retry_task
  - align_and_deliver
  - handle_transport_notify_disconnect
* hostlist (everything)
* topology (everything)



PHASE #2: (Goal: recover basic file-sharing functionality)

Datastores:
* implement sqlite-based sqstore/datastore service
  + implement service (datastore + talks to plugin)
  + implement library (talks to service)
  + implement sqlite plugin (talks to DB)
  + fix testcases (make them use CPS, complete their inner workings...)
* implement sqlite-based dstore services
  + design API
  + implement library (talks to service)
  + implement service (talks to plugin)
  + implement sqlite plugin (talks to DB)

Applications:
* DHT, DV
* FS / fs-libs



PHASE #3: (Goal: ready for pre-release) [completion-goal: end of 2009]

* testing
* setup
* gtk, qt GUIs
* tbench
* tracekit
* vpn

Transports:
* UDP backend (need LIBRARY to support (de)fragmentation!)
* HTTP backend
* Testing:
  + Testcases for set_quota, timeouts, disconnects, transmit_ready_cancel
  + Better coverage of gnunet-service-transport (HELLO validation)
  + direct test of plugins compliance to plugin API

Databases:
* sqlite, mysql & postgres backend



Minor TODO items:
* UTIL:
  - crypto_hash: use libgcrypt (supports SHA-512 since 2003)
  - container_bloomfilter: improve efficiency (see FIXME)
* SERVER:
  - inefficient memmove
* TRANSPORT:
  - transport_api: support forcing disconnects through low quotas!
    (required for working F2F support!)
  - API: consider having core provide deadline information for each message
    (likely important for DV plugin which wants to loop back!)
  - implement transport API to pretty-print transport address 
    + transport_api extension (API extension!)
    + service-transport extension (protocol extension)
  - add calls to statistics in various places
  - implement gnunet-transport (transport configurator / tester)
  - UPnP-based IP detection
    (Note: build library always, build service when libxml2/etc. are available)
  - instantly filter addresses from *other* peers that 
    are *equal* to our own address + port (i.e., localhost:2086).  We 
    no longer filter those for outgoing (helps with loopback testing
    and keeps the code clean), but we should filter strictly *impossible*
    incoming addresses!  This is for efficiency, not correctness.
  - We currently are happy to take any address told to us in a WELCOME
    to our set of addresses; we should have some minimal threshold-based
    scheme, limiting both the total number of addresses that we accept 
    this way as well as requiring multiple confirmations; also, we
    should possibly try to confirm that the given address works for
    us ourselves (loopback-style) before adding it to the list
    [SECURITY issue]
    + we may be able to simplify WELCOME messages (no need to add 
      addresses there anymore, but may help to learn them there anyway...).
    + we probably want some kind of voting/counting for learning IP addresses
      (maybe including IP addresses in ads proportional to how often others
       report them? we at least need some protection against >64k HELLOs!),
    + provide a way to give the user a list of "learned" IP addresses and
      a way to easily "veto" addresses off the list!
      => If MiM attacker uses vetoed address, blacklist the specific IP for
         the presumed neighbour!
  - not sure current way of doing ACKs works well-enough 
    with unreliable transports where the ACK maybe lost;
    the "is_new" check would then possibly prevent future
    ACKs to be delivered, all while we're happily 
    receiving messages from that peer!  Worse, the other
    peer won't generate another ACK since it thinks we're
    connected just fine...
    Key questions:
    + How necessary is ACKing in the first place? (alternatives?)
    + Should we transmit ACKs in response to every HELLO? (would that 
      fully address the problem?)
  - latency measurements implemented in the transport
    plugins makes it only work for bi-di transports
    and results in code replication
  - should latency be included in the ReceiveCallback and
    NotifyConnect or passed on request?
  - FIXME's with latency being simply set to 0 in a few places
  - Memory leak (running valgrind --trace-children=yes on test_transport_api:   
    ==28393== 16 bytes in 1 blocks are indirectly lost in loss record 1 of 5
    ==28393==    at 0x4C2260E: malloc (vg_replace_malloc.c:207)
    ==28393==    by 0x52343E3: GNUNET_xmalloc_unchecked_ (common_allocation.c:62)
    ==28393==    by 0x5234389: GNUNET_xmalloc_ (common_allocation.c:53)
    ==28393==    by 0x524458A: GNUNET_NETWORK_socket_create_from_accept (network.c:289)
    ==28393==    by 0x524B2DA: ??? (server.c:332)
    ==28393==    by 0x524A4C7: ??? (scheduler.c:425)
    ==28393==    by 0x524A73D: GNUNET_SCHEDULER_run (scheduler.c:510)
    ==28393==    by 0x524FF8C: GNUNET_SERVICE_run (service.c:1326)
    ==28393==    by 0x405500: main (gnunet-service-transport.c:2645)
    And also:
    ==28393== 65,744 (65,728 direct, 16 indirect) bytes in 1 blocks are definitely lost in loss record 5 of 5
    ==28393==    at 0x4C2260E: malloc (vg_replace_malloc.c:207)
    ==28393==    by 0x52343E3: GNUNET_xmalloc_unchecked_ (common_allocation.c:62)
    ==28393==    by 0x5234389: GNUNET_xmalloc_ (common_allocation.c:53)
    ==28393==    by 0x524473E: GNUNET_NETWORK_socket_create_from_accept (network.c:323)
    (rest of trace identical)

* SETUP:
  - auto-generate "defaults.conf" using gnunet-setup from "config.scm"
  - integrate all options into "config.scm"
  - change config-file writing to exclude options set to default values
* ARM:
  - implement exponential back-off for service restarts
  - better tracking of which config changes actually need to cause process restarts by ARM.
  - have way to specify dependencies between services (to manage ARM restarts better)
  - client-API is inefficient since it opens a TCP connection per service that is started
    (instead of re-using connections).
* CORE: 
  - code currently notifies clients about "encrypted" connections being up well before
    we get the encrypted PONG; sometimes this may be OK (for topology killing
    unwanted connnections), but of course not in general.  I suspect we want
    to signal on PONG and have topology hook directly into transport to
    kill plaintext connections before they have a chance to become encrypted
    (may require minor hack in transport API)
* PEERINFO:
  - have gnunet-peerinfo print actual host addresses again
  - add option to gnunet-peerinfo to modify trust value
* POSTGRES-DB:
  - finish postgres implementation; simplify other SQLs using new stats
* HTTPS transport
  - PolariSSL for MHD?
  - https integration
* GAP improvements:
  - active reply route caching design & implementation of service,
    gap extension!
* HOSTLIST:
  - implement advertising of hostlist URL
  - implement learning of hostlist URLs



=> PRE-RELEASE

PHASE #4: [completion-goal: mid 2010]
* Documentation
* new webpage




Stuff to remember:
* Features eliminated from util:
  - threading (goal: good riddance!)
  - complex logging features [ectx-passing, target-kinds] (goal: good riddance!)
  - complex configuration features [defaults, notifications] (goal: good riddance!)
  - network traffic monitors (goal: eliminate)
  - IPC semaphores (goal: d-bus? / eliminate?)
  - second timers
  - DNS lookup (goal: have async service; issue: still need synchronous resolution in places, current code may not be portable)
  => code shrunk from 61 files to 34, 22k LOC to 15k LOC, 470k to 330k (with symbols)
* New features in util:
  - scheduler
  - service and program boot-strap code
* Major changes in util:
  - more expressive server (replaces selector)
* Open questions: 
  - how to integrate scheduler with GTK event loop!



Test coverage:
* UTIL      : 78.7%
* HELLO     : 93.7%
* ARM       : 69.9%
* RESOLVER  : 60.4%
* STATISTICS: 82.8%
* PEERINFO  : 71.5%
* TRANSPORT : 70.9%
* CORE      : 65.8%
===================
* TOTAL     : 74.9%

Not yet tested:
* HOSTLIST  :  0.0%
* TOPOLOGY  :  0.0%