OpenBMC webserver

This component attempts to be a "do everything" embedded webserver for openbmc.

Capabilities

At this time, the webserver implements a few interfaces:

• Authentication middleware that supports cookie and token based authentication, as well as CSRF prevention backed by linux PAM authentication credentials.
• An (incomplete) attempt at replicating phosphor-dbus-rest interfaces in C++. Right now, a few of the endpoint definitions work as expected, but there is still a lot of work to be done. The portions of the interface that are functional are designed to work correctly for phosphor-webui, but may not yet be complete.
• Replication of the rest-dbus backend interfaces to allow bmc debug to logged in users.
• An initial attempt at a read-only redfish interface. Currently the redfish interface targets ServiceRoot, SessionService, AccountService, Roles, and ManagersService. Some functionality here has been shimmed to make development possible. For example, there exists only a single user role.
• SSL key generation at runtime. See the configuration section for details.
• Static file hosting. Currently, static files are hosted from the fixed location at /usr/share/www. This is intended to allow loose coupling with yocto projects, and allow overriding static files at build time.
• Dbus-monitor over websocket. A generic endpoint that allows UIs to open a websocket and register for notification of events to avoid polling in single page applications. (this interface may be modified in the future due to security concerns.

Configuration

BMCWeb is configured by setting -D flags that correspond to options in bmcweb/meson_options.txt and then compiling. For example, meson <builddir> -Dkvm=disabled ... followed by ninja in build directory. The option names become C++ preprocessor symbols that control which code is compiled into the program.

Compile bmcweb with default options:

meson builddir
ninja -C builddir

Compile bmcweb with yocto defaults:

meson builddir -Dbuildtype=minsize -Db_lto=true -Dtests=disabled
ninja -C buildir

If any of the dependencies are not found on the host system during configuration, meson automatically gets them via its wrap dependencies mentioned in bmcweb/subprojects.

Enable/Disable meson wrap feature

meson builddir -Dwrap_mode=nofallback
ninja -C builddir

Enable debug traces

meson builddir -Dbuildtype=debug
ninja -C builddir

Generate test coverage report:

meson builddir -Db_coverage=true -Dtests=enabled
ninja coverage -C builddir test

When BMCWeb starts running, it reads persistent configuration data (such as UUID and session data) from a local file. If this is not usable, it generates a new configuration.

When BMCWeb SSL support is enabled and a usable certificate is not found, it will generate a self-sign a certificate before launching the server. The keys are generated by the secp384r1 algorithm. The certificate

• is issued by C=US, O=OpenBMC, CN=testhost,
• is valid for 10 years,
• has a random serial number, and
• is signed using the SHA-256 algorithm.