This component attempts to be a "do everything" embedded webserver for openbmc.
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.
BMCWeb is configured by setting -D flags that correspond to options
in bmcweb/CMakeLists.txt and then compiling. For example, cmake -DBMCWEB_ENABLE_KVM=NO ... followed by make. The option names
become C++ preprocessor symbols that control which code is compiled
into the program.
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 prime256v1 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-256algorithm.