libnetconf2 is a NETCONF library in C intended for building NETCONF clients and servers. NETCONF is the [NETwork CONFiguration protocol] (http://trac.tools.ietf.org/wg/netconf/trac/wiki) introduced by IETF.
The library provides functions to connect NETCONF client and server to each other via SSH and to send, receive and process NETCONF messages. In contrast to the previous libnetconf library, libnetconf2 does not include NETCONF datastore implementation. This functionality is left specific to the NETCONF server implementation.
libnetconf2 is maintained and further developed by the Tools for Monitoring and Configuration department of CESNET. Any testing of the library is welcome. Please inform us about your experiences with using libnetconf2 via the issue tracker.
libnetconf2 is being developed with experiences gained from the development of the libnetconf library. This previous generation of our NETCONF library is built on libxml2, used to internally represent all the data. In libnetconf2, we have completely replaced libxml2 by libyang. The libyang library is much more efficient in work with YANG modeled data (which is the case of NETCONF messages) and this advantage then applies also to libnetconf2. The library is connected with YANG, so for example data validation according to the provided YANG schemas is done internally instead of using external DSDL tools (as it was in the first generation of libnetconf).
libnetconf2 is currently being developed, and some (server-side) functions are not yet implemented. Feedback and bug reports concerning problems not mentioned here are appreciated via the issue tracker.
Install the following libraries and tools the libnetconf2 depends on.
Follow the libyang instructions, in short:
$ git clone https://github.com/CESNET/libyang.git
$ cd libyang; mkdir build; cd build
$ cmake ..
$ make
# make install
Required version is at least 0.6.4. This dependency can be removed by disabling SSH support (see the Build Options section). Below si the basic sequence of commands for compiling and installing it from source. However, there are packages for certain Linux distributions available here.
$ git clone http://git.libssh.org/projects/libssh.git
$ cd libssh; mkdir build; cd build
$ cmake ..
$ make
# make install
This dependency is required when the TLS support is enabled, which it is by default but libssh requires it too. So, to remove this dependency, you need to disable both SSH and TLS (see the Build Options section).
OpenSSL is a standard part of the most distribution, so ask your package manager for OpenSSL package including the necessary development files (usually -dev or -devel package).
It is required only if DNSSEC SSHFP retrieval is enabled (it is disabled by default, see the Build Options secion).
The easier way of installing it is as the libval-dev package (or a part of the dnssec-tools package), if you can find it for your distribution. Packages for some distributions or the source can be downloaded from here.
For running the tests (see the Tests section for more information).
$ git clone git://git.cryptomilk.org/projects/cmocka.git
$ cd cmocka
$ git checkout tags/cmocka-1.0.1
$ mkdir build; cd build
$ cmake ..
$ make
# make install
For building the library documentation.
Doxygen is a standard part of the most distribution, so ask your package manager for doxygen package.
$ mkdir build; cd build
$ cmake ..
$ make
# install
The library documentation can be generated directly from the source codes using Doxygen tool:
$ make doc
There are various options to change result of building.
Set CC environment variable:
$ CC=/usr/bin/clang cmake ..
By default, the library is installed with the /usr/local prefix, to change
it, use the following option:
$ cmake -DCMAKE_INSTALL_PREFIX:PATH=/usr ..
The NETCONF protocol specification allows to use the protocol on top of several transport protocols. libnetconf2 provides support for SSH and TLS transport. By default, both SSH and TLS transport is enabled. Disabling and enabling both the transport protocols can be made in the same way. The following command has actually the same effect as specifying no option since it specifies the default settings.
$ cmake -DENABLE_TLS=ON -DENABLE_SSH=ON ..
In SSH connections, if the remote NETCONF server supports it and it is enabled, it is possible to safely retrieve server host key fingerprints using DNSSEC and automatically consider them to be trusted without any interaction. Enable it with the following command.
$ cmake -DENABLE_DNSSEC=ON ..
There are two build modes:
- Release. This generates library for the production use without any debug information.
- Debug. This generates library with the debug information and disables optimization of the code.
The Debug mode is currently used as the default one. to switch to the
Release mode, enter at the command line:
$ cmake -D CMAKE_BUILD_TYPE:String="Release" ..
Note that, with CMake, if you want to change the compiler or its options after you already ran CMake, you need to clear its cache first - the most simple way to do it is to remove all content from the 'build' directory.
The repository includes several tests built with cmocka.
The tests can be found in tests subdirectory and they are designed for
checking library functionality after code changes.
The tests are by default built in the Debug build mode by running
$ make
In case of the Release mode, the tests are not built by default (it requires
additional dependency), but it can be enabled via cmake option:
$ cmake -DENABLE_BUILD_TESTS=ON ..
Note that if the necessary cmocka headers are not present in the system include paths, tests are not available despite the build mode or cmake's options.
Tests can be run by the make's test target:
$ make test