bitc is a thin SPV bitcoin client.
- 100% C11,
- support for Linux, macOS,
- ncurses-based TUI,
- home-grown async network I/O (single-threaded poll(2) loop),
- home-grown Bitcoin P2P engine,
- BIP157/158 compact block filters (not BIP37),
- encrypted wallet (AES-256-CBC via OpenSSL EVP),
- Tor/SOCKS5 support,
- CPU offload pool for signature verification,
- clean under ASan and UBSan.
WARNING: this app is experimental and should not be used as a secure wallet. See TODO.md for the modernization roadmap.
These are discovered at build time via pkg-config, so install them with your
package manager (e.g. brew install openssl leveldb snappy curl cjson pkg-config
on macOS, or the matching -dev packages on Debian/Ubuntu:
libssl-dev libleveldb-dev libsnappy-dev libcurl4-openssl-dev libncurses-dev libcjson-dev pkg-config).
- OpenSSL: crypto library (EC keys, ECDSA, AES), used via the OpenSSL 3 EVP API. https://www.openssl.org/
- LevelDB: Google's key/value store for the transaction db, BSD 3-Clause. https://github.com/google/leveldb (with Snappy for compression).
- libcurl: HTTP client (fx rates, ip info), MIT/X derivative. https://curl.se/libcurl/
- ncurses (with panel/form): the console UI.
- cJSON: JSON parser, MIT. https://github.com/DaveGamble/cJSON
MurmurHash3 (public domain) is bundled under ext/src/.
You first need to install the build tools and libraries this app uses:
# sudo apt-get install git make clang pkg-config
# sudo apt-get install libssl-dev libcurl4-openssl-dev libncurses-dev
# sudo apt-get install libleveldb-dev libsnappy-dev libcjson-dev
then clone the git repository:
# git clone https://github.com/mx4/bitc.git
finally build and launch:
# cd bitc && make
# ./bitc
Install the dependencies via brew (or port):
# brew install pkg-config openssl leveldb snappy curl ncurses cjson
then build and launch:
# cd bitc && make
# ./bitc
bitc can run headless without the ncurses UI:
./bitc -d # daemon, no TUI
./bitc -d --connect <ip> # pin a specific peer
./bitc -d --sync-and-exit # sync headers then quit
./bitc -z # wipe blockstore, addrbook, txdb
The -e flag encrypts the wallet interactively. Self-tests: ./bitc -t 0.
make # debug build (default)
make BUILD=release
make BUILD=asan # AddressSanitizer
make BUILD=ubsan # UndefinedBehaviorSanitizer
make check # build + run fuzz-parse and test-gcs
make tags # ctags index
The first time you launch the app, a message will notify you of the list of files & directory it uses.
bitc uses the folder ~/.bitc to store various items:
| what | where | avg size |
|---|---|---|
| block headers | ~/.bitc/headers.dat | ~ 75MB |
| peer IP addresses | ~/.bitc/peers.dat | ~ 1MB |
| transaction database | ~/.bitc/txdb | < 1MB |
| config file | ~/.bitc/main.cfg | < 1KB |
| wallet keys | ~/.bitc/wallet.cfg | < 1KB |
| tx-label file | ~/.bitc/tx-labels.cfg | < 1KB |
| contacts file | ~/.bitc/contacts.cfg | < 1KB |
A log file is generated in /tmp/bitc-$USER.log.
To navigate the UI:
<left>and<right>allow you to change panel,<CTRL>+tto initiate a transaction,- type
qorback quoteto exit.
bitc has support for encrypted wallets. The first time you launch the app, it will automatically generate a new bitcoin address for you, and the wallet file will have private key unencrypted.
To turn on encryption, or to change the encryption password:
# ./bitc -e
The next time you launch the app, you may or may not specify -p on
the command line. If you do, you will be able to initiate transactions. If you
do not the dashboard will still be functional but you won't be able to
initiate transactions.
Note that bitc encrypts each private key separately.
WARNING: please remember to make back-ups.
Bitc can route all outgoing TCP connections through a socks5 proxy. Since TOR implements a SOCKS5 proxy, you just need to put the entry:
network.useSocks5="true"
in your main config file to use bitc over Tor (for a local Tor client). If the Tor proxy is not running locally, you need to modify the config options:
socks5.hostname="localhost"
socks5.port=9050
.. in the file ~/.bitc/main.cfg. The default hostname:port is
localhost:9050 on linux, and localhost:9150 on mac.
If you tag a key as
key0.spendable = "FALSE"
in your ~/.bitc/wallet.cfg, bitc won't attempt to spend the bitcoins held by
this address. This is not quite like a watch-only address, but we'll get there
eventually.
There are still a variety of things that need to be fixed or implemented (cf TODO file), and some of these may explain the behavior you're seeing. If bitc crashes, please collect the log file along with the core dump and open a ticket on github:
https://github.com/mx4/bitc/issues
Feel free to reach out to me if you have any feedback or if you're planning to use this code in interesting ways.
mailto:austruym@gmail.com PGP: 1C774FA3925A3076752B2741054E32DFBEE883DB