dhtd

Utilize the BitTorrent network for hash identifier storage and lookup.

mwarning
19
1
C

DHTd

A standalone Kademlia DHT (Distribute Hash Table) to connect to the mainline BitTorrent network.

A Distributed Hash Table (DHT) is a distributed system storing key/value pairs used by BitTorrent clients to find peers. DHTd can be used in the same way to find the IP address of other instances in a decentralized way without any authentication. Or you can use it as a bootstrap node.

Otherwise you can think of it as a Tamagotchi for people who are into decentralized networks. 😃

Features:

  • small at 110KB
  • announce and lookup for hashes
  • local peer discovery
  • run as bootstrap node
  • scripting capabilities
  • only libc as dependency
  • available for OpenWrt

Quick Start

Compile

Compilation is rather simple:

$ git clone https://github.com/mwarning/dhtd.git
$ cd dhtd
$ make
[...]
$ ./build/dhtd -h

(The $ is the terminal prompt, it is included here to distinguish commands from program output)

Run

Run DHTd in background:

$ dhtd --daemon --peer bttracker.debian.org:6881 --peer router.bittorrent.com:6881

Example output after a few minutes:

$ dhtd-ctl status
DHTd 1.0.0 ( cli debug lpd )
DHT id: 24e56b174415846be9050d628e8d8c0eda42de96
DHT uptime: 120d6h
DHT listen on: IPv4+IPv6 / device: <any> / port: 6881
DHT nodes: 1090 IPv4 (402 good), 373 IPv6 (349 good)
DHT storage: 280 entries with 648 addresses
DHT searches: 0 IPv4 (0 done), 0 IPv6 active (0 done)
DHT announcements: 0
DHT blocklist: 3
DHT traffic: 24.6 G, 6.8 K/s (in) / 68.5 G, 2.5 K/s (out)

Start a search:

$ dhtd-ctl search 6f84758b0ddd8dc05840bf932a77935d8b5b8b93
Search started.

(the id is from a magnet link of a Debian Linux torrent file)

After a few seconds:

$ dhtd-ctl results 6f84758b0ddd8dc05840bf932a77935d8b5b8b93
[2a01:e0a:ea:d9d0::1]:24007
[2a01:e0a:5c4:f490::1]:26915
[2001:470:8:62b:c41a:db05:69db:bb]:59863
[2001:bc8:32d7:25e::42]:51413
[2003:d6:af28:9200:dea6:32ff:fec4:6592]:50476
[2003:e6:2f01:8400::65e]:63746
[2003:e6:2f01:8400:6a6:6b4b:8433:95dd]:63746
[2003:f6:3f2b:3300::1]:51413
[2601:18d:8d7f:e566:beae:c5ff:fe66:ec70]:6881
[2603:8001:4000:6d07:549d:1d6a:9b33:b14f]:38934

Note:

  • Searches/Results are discarded after about 62 minutes.
  • You cannot search for the id of the node itself, only ids that someone announced.
  • Use lookup to start/continue a search and also print out results.
  • Use --execute <file> command line argument to execute a script for each result.

Command Line Arguments

Startup command line arguments for dhtd.

  • --announce id[:port]
    Announce a id and optional port.
    This option may occur multiple times.
  • --peerfile file
    Import/Export peers from and to a file.
  • --peer address
    Add a static peer address.
    This option may occur multiple times.
  • --execute file
    Execute a script for each result.
  • --port port
    Bind DHT to this port.
    Default: 6881
  • --config file
    Provide a configuration file with one command line
    option on each line. Comments start after ‘#’.
  • --ifname interface
    Bind to this interface.
    Default: any
  • --daemon, -d
    Run the node in background.
  • --verbosity level
    Verbosity level: quiet, verbose or debug.
    Default: verbose
  • --user user
    Change the UUID after start.
  • --pidfile file
    Write process pid to a file.
  • --ipv4, -4, --ipv6, -6
    Enable IPv4 or IPv6 only mode.
    Default: IPv4+IPv6
  • --lpd-disable
    Disable multicast to discover local peers.
  • --cli-disable-stdin
    Disable the local control interface.
  • --cli-path path
    Bind the remote control interface to this unix socket path.
    Default: /tmp/dhtd.sock
  • --help, -h
    Print this help.
  • --version, -v
    Print program version.

Command Line Interface

List of commands that can be send to a running dhtd instance via the command line control interface dhtd-ctl.

  • status
    The current state of this node.
  • lookup <id>
    Start search and print results.
  • search <id>
    Start a search for announced values.
  • results <id>
    Print the results of a search.
  • announce-start <id>[:<port>]
    Start to announce an id along with a network port.
  • announce-stop <id>
    Stop the announcement.
  • searches
    Print a list of all searches. They expire after 62min.
  • announcements
    Print a list of all announcements.
  • peer <address>:<port>
    Add a peer by address.
  • constants|blocklist|peers|buckets|storage
    Print various internal data.

Legend:

<id> 20 bytes as hexadecimal string

<port> Network port number between 1-65536

<address> IPv4 or IPv6 address

License

MIT/X11

Authors

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