libwally-core
Wally is a cross-platform, cross-language collection of useful primitives for cryptocurrency wallets.
Read the API documentation at https://wally.readthedocs.io.
Note that library interfaces may change slightly while the library design matures. Please see the CHANGES file to determine if the API has changed when upgrading.
Please report bugs and submit patches to Our github repository. If you wish to report a security issue, please read Our security reporting guidelines.
Platforms
Wally can currently be built for:
- Linux
- Android
- macOS
- iOS
- Windows
- Embedded (e.g ESP-32)
- WebAssembly
And can be used from:
- C and compatible languages which can call C interfaces
- C++ (see include/wally.hpp for C++ container support)
- Python 3.x
- Java
- Javascript via node.js or web browser.
Building
# Initialise the libsecp sources (Needs to be run only once)
$ git submodule init
$ git submodule sync --recursive
$ git submodule update --init --recursive
# Build
$ ./tools/autogen.sh
$ ./configure <options - see below>
$ make
$ make check
Building on macOS
Using homebrew,
$ brew install gnu-sed
If you wish to enable the SWIG interface, you will need install the Java JDK 8 or newer, and install SWIG:
$ brew install swig
configure options
--enable-debug
. Enables debugging information and disables compiler optimisations (default: no).--enable-minimal
. Minimises library size and memory requirements to target embedded or resource-constrained environments (default: no).--enable-asm
. Enables fast assembly language implementations where available. (default: enabled for non-debug builds).--enable-export-all
. Export all functions from the wally shared library. Ordinarily only API functions are exported. (default: no). Enable this if you want to test the internal functions of the library or are planning to submit patches.--enable-swig-python
. Enable the SWIG Python interface. The resulting shared library can be imported from Python using the generated interface filesrc/swig_python/wallycore/__init__.py
. (default: no).--enable-python-manylinux
. Enable manylinux support for building PyPI compatible python wheels. Using the resulting library in non-python programs requires linking withlibpython.so
.--enable-swig-java
. Enable the SWIG Java (JNI) interface. After building, seesrc/swig_java/src/com/blockstream/libwally/Wally.java
for the Java interface definition (default: no).--enable-elements
. Enables support for Elements features, including Liquid support.--enabled-standard-secp
. Excludes support for features that are unavailable in the standard libsecp256k1 library.--enable-mbed-tls
. Use mbed-tls hashing functions if available. This typically results in faster hashing on embedded platforms such as STM32. Note that the user must defineMBEDTLS_SHA256_ALT
and/orSOC_SHA_SUPPORT_PARALLEL_ENG
matching the SOC support when compiling the library. (default: no)--enable-coverage
. Enables code coverage (default: no) Note that you will need lcov installed to build with this option enabled and generate coverage reports.--disable-shared
. Disables building a shared library and builds a static library instead.--disable-tests
. Disables building library tests.--disable-clear-tests
. Disables just the test_clear test (required to pass the test suite with some compilers).
Recommended development configure options
$ ./configure --enable-debug --enable-export-all --enable-swig-python --enable-swig-java --enable-coverage
Compiler options
Set CC=clang
to use clang for building instead of gcc, when both are
installed.
Python
For non-development use, you can install wally with pip
as follows:
pip install wallycore==0.9.0
For python development, you can build and install wally using:
$ pip install .
It is suggested you only install this way into a virtualenv while the library is under heavy development.
If you wish to explicitly choose the python version to use, set the
PYTHON_VERSION
environment variable (to e.g. 3
, 3.7
etc) before
running pip
or (when compiling manually) ./configure
.
You can also install the binary wally releases using the released wheel files without having to compile the library, e.g.:
pip install wallycore-0.9.0-cp39-cp39m-linux_x86_64.whl
The script tools/build_python_manylinux_wheels.sh
builds the Linux release files
and can be used as an example for your own python projects.
Android
Android builds are currently supported for all Android binary targets using
the Android NDK. The script tools/android_helpers.sh
can be sourced from
the shell or scripts to make it easier to produce builds:
$ export ANDROID_NDK=/opt/android-ndk-r23b # r22 is the minimum supported version
$ . ./tools/android_helpers.sh
$ android_get_arch_list
armeabi-v7a arm64-v8a x86 x86_64
# Prepare to build
$ ./tools/cleanup.sh
$ ./tools/autogen.sh
# See the comments in tools/android_helpers.sh for arguments
$ android_build_wally armeabi-v7a $ANDROID_NDK/toolchains/llvm/prebuilt/linux-x86_64 19 "--enable-swig-java"
The script tools/build_android_libraries.sh
builds the Android release files and
can be used as an example for your own Android projects.
WebAssembly
WebAssembly is available as a preview feature. Users may want to avoid using wally compiled for wasm for signing or encryption/decryption as the transpiled code may not remain constant time.
Building wally as wasm requires following emsdk instructions for
your platform and sourcing
the emsdk_env.sh
file:
# Set up the environment variables for the toolchain
$ source $HOME/emsdk/emsdk_env.sh
# Optionally set the list of wally functions to export to wasm (default: all)
$ export EXPORTED_FUNCTIONS="['_malloc','_free','_wally_init','_wally_cleanup',...]"
# Build
$ ./tools/build_wasm.sh [--enable-elements]
Note that emsdk v3.1.27 or later is required.
The script tools/build_wasm.sh
builds the wallycore.html
example as well
as the required wallycore.js
and wallycore.wasm
files, which can be used
as an example for your own WebAssembly projects.
Open wallycore.html
in a browser via a webserver like nginx
or python2 -m SimpleHTTPServer 8000
to run the example.
Cleaning
$ ./tools/cleanup.sh
Submitting patches
Please use pull requests on github to
submit. Before producing your patch you should format your changes
using uncrustify version 0.60 or
later. The script ./tools/uncrustify
will reformat all C sources in the library
as needed, with the currently chosen uncrustify options.
To reformat a single source file, use e.g.:
$ ./tools/uncrustify src/transaction.c
Or to reformat all source files, pass no arguments:
$ ./tools/uncrustify
If you have added new API functions in your patch, run tools/update_generated.sh
to update the auto-generated support code for various platforms. This requires
Python and the jq
binary.
You should also make sure the existing tests pass and if possible write tests covering any new functionality, following the existing style. You can run the tests via:
$ make check
Python ctypes tests (in ./src/test/
) are strongly preferred, but you can add
to the other test suites if your changes target a specific language or your
tests need to be written at a higher level of abstraction.
Generating a coverage report
To generate an HTML coverage report, install lcov
and use:
$ ./tools/cleanup.sh
$ ./tools/autogen.sh
$ ./configure --enable-debug --enable-export-all --enable-swig-python --enable-swig-java --enable-coverage --enable-elements
$ make
$ ./tools/coverage.sh clean
$ make check
$ ./tools/coverage.sh
For coverage with clang
, you need to install llvm-cov
, typically via the
llvm-<version>
package that corresponds to your clang
version. Once
installed, set the GCOV
environment variable to the versioned llvm-cov
binary name before running ./tools/coverage.sh
, e.g:
$ GCOV=llvm-cov-11 ./tools/coverage.sh clean
$ make check
$ GCOV=llvm-cov-11 ./tools/coverage.sh
The coverage report can be viewed at ./src/lcov/src/index.html
. Patches
to increase the test coverage are welcome.
Users of libwally-core
Projects and products that are known to depend on or use libwally
:
- Blockstream Green Command Line Wallet
- Blockstream Green Development Kit
- Blockstream Green Wallet for Android
- Blockstream Green Wallet for iOS
- Blockstream Green Wallet for Desktops
- Blockstream Jade Hardware Wallet
- BitBox02 Hardware Wallet
- Blockstream Blind PIN Server
- Blockstream/liquid-melt
- Blockstream/liquid_multisig_issuance
- c-lightning
- gdk_rpc for bitcoind/liquidd
- GreenAddress Recovery Tool
- GreenAddress Wallet for Windows/Mac/Linux
- GreenAddress Web Files
- LibWally Swift
- Multy-Core
Please note that some of the listed projects may be experimental or superseded.