What is Anjay?
Anjay is a C library that aims to be the reference implementation of the OMA Lightweight Machine-to-Machine (LwM2M) device management protocol. It eases development of fully-featured LwM2M client applications by taking care of protocol details, allowing the user to focus on device-specific aspects.
The project has been created and is actively maintained by AVSystem.
- Supported features
- About OMA LwM2M
- Quickstart guide
LwM2M Bootstrap Interface:
LwM2M Client Registration Interface:
LwM2M Device Management and Service Enablement Interface:
LwM2M Information Reporting Interface:
- Cancel Observation
LwM2M Security modes:
- DTLS with Certificates (if supported by backend TLS library)
- DTLS with PSK (if supported by backend TLS library)
- NoSec mode
Supported TLS backends:
- mbed TLS
CoAP data formats:
- Plain Text (including base64 encoding of opaque data)
CoAP BLOCK transfers (for transferring data that does not fit in a single UDP packet):
- Block1 (sending / receiving requests)
- Block2 (sending responses)
Pre-implemented LwM2M Objects:
- Access Control
Stream-oriented persistence API
About OMA LwM2M
OMA LwM2M is a remote device management and telemetry protocol designed to conserve network resources. It is especially suitable for constrained wireless devices, where network communication is a major factor affecting battery life. LwM2M features secure (DTLS-encrypted) methods of remote bootstrapping, configuration and notifications over UDP or SMS.
More details about OMA LwM2M: Brief introduction to LwM2M
- C compiler with C99 support,
- CMake 2.8.11+,
- avs_commons - included in the repository as a subproject,
- If DTLS support is enabled, at least one of:
- Optional dependencies (required for tests):
Ubuntu 16.04 LTS
sudo apt-get install git build-essential cmake libmbedtls-dev # Optionally for tests: sudo apt-get install libpython3-dev libssl-dev python3 python3-cryptography python3-jinja2 python3-sphinx clang
# Required for mbedtls-devel and python3.5 sudo yum install -y https://centos7.iuscommunity.org/ius-release.rpm sudo yum install -y which git make cmake mbedtls-devel gcc gcc-c++ # Optionally for tests: sudo yum install -y valgrind valgrind-devel openssl openssl-devel python35u python35u-devel python35u-pip python-sphinx python-sphinx_rtd_theme clang-analyzer # Some test scripts expect Python >=3.5 to be available via `python3` command # Use update-alternatives to create a /usr/bin/python3 symlink with priority 0 # (lowest possible) sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.5 0 sudo python3 -m pip install cryptography jinja2
brew install cmake mbedtls # Optionally for tests: brew install python3 openssl llvm pip3 install cryptography sphinx sphinx_rtd_theme
Running the demo client
To compile Anjay demo client and connect it to a local LwM2M server listening on default 5683 port:
git clone https://github.com/AVSystem/Anjay.git \ && cd Anjay \ && git submodule update --init \ && cmake . \ && make -j \ && ./output/bin/demo --server-uri coap://127.0.0.1:5683
Detailed compilation guide
First, make sure all necessary submodules are downloaded and up-to-date:
git submodule update --init
By default demo client compiles with DTLS enabled and uses
mbedtls as a DTLS provider,
but you may choose other DTLS backends currently supported by setting
a CMake invocation to one of the following DTLS backends:
cmake . -DDTLS_BACKEND="mbedtls" && make -j
Or, if a lack of security (not recommended) is what you need for some reason:
cmake . -DDTLS_BACKEND="" && make -j
Compiled executables, including demo client, can be found in output/bin subdirectory.
For a detailed guide on configuring and compiling the project (including cross-compiling), see Compiling client applications.
To start the demo client:
# uses plain CoAP ./output/bin/demo --server-uri coap://127.0.0.1:5683 # uses DTLS in PSK mode, with PSK identity "foo" and secret key "bar" (hex-encoded) ./output/bin/demo --server-uri coaps://127.0.0.1:5684 --security-mode psk --identity 666f6f --key 626172
NOTE: When establishing a DTLS connection, the URI MUST use "coaps://". In NoSec mode (default), the URI MUST use "coap://".
Running tests on Ubuntu 16.04:
./devconfig && make check
Running tests on CentOS 7:
# NOTE: clang-3.4 static analyzer (default version for CentOS) gives false # positives. --without-analysis flag disables static analysis. ./devconfig --without-analysis -DPython_ADDITIONAL_VERSIONS=3.5 && make check
Running tests on macOS Sierra:
# If the scan-build script is located somewhere else, then you need to # specify a different SCAN_BUILD_BINARY. Below, we are assumming scan-build # comes from an llvm package, installed via homebrew. ./devconfig -DSCAN_BUILD_BINARY=/usr/local/Cellar/llvm/*/bin/scan-build && make check
See LICENSE file.
Anjay LwM2M library comes with the option of full commercial support, provided by AVSystem.
Contributions are welcome! See our contributing guide.