1# OpenBMC webserver 2 3This component attempts to be a "do everything" embedded webserver for OpenBMC. 4 5## Features 6 7The webserver implements a few distinct interfaces: 8 9- DBus event websocket. Allows registering on changes to specific dbus paths, 10 properties, and will send an event from the websocket if those filters match. 11- OpenBMC DBus REST api. Allows direct, low interference, high fidelity access 12 to dbus and the objects it represents. 13- Serial: A serial websocket for interacting with the host serial console 14 through websockets. 15- Redfish: A protocol compliant, [DBus to Redfish translator](docs/Redfish.md). 16- KVM: A websocket based implementation of the RFB (VNC) frame buffer protocol 17 intended to mate to webui-vue to provide a complete KVM implementation. 18 19## Protocols 20 21bmcweb at a protocol level supports http and https. TLS is supported through 22OpenSSL. Http1 and http2 are supported using ALPN registration for TLS 23connections and h2c upgrade header for http connections. 24 25## AuthX 26 27### Authentication 28 29Bmcweb supports multiple authentication protocols: 30 31- Basic authentication per RFC7617 32- Cookie based authentication for authenticating against webui-vue 33- Mutual TLS authentication based on OpenSSL 34- Session authentication through webui-vue 35- XToken based authentication conformant to Redfish DSP0266 36 37Each of these types of authentication is able to be enabled or disabled both via 38runtime policy changes (through the relevant Redfish APIs) or via configure time 39options. All authentication mechanisms supporting username/password are routed 40to libpam, to allow for customization in authentication implementations. 41 42### Authorization 43 44All authorization in bmcweb is determined at routing time, and per route, and 45conform to the Redfish PrivilegeRegistry. 46 47\*Note: Non-Redfish functions are mapped to the closest equivalent Redfish 48privilege level. 49 50## Configuration 51 52bmcweb is configured per the 53[meson build files](https://mesonbuild.com/Build-options.html). Available 54options are documented in `meson_options.txt` 55 56## Compile bmcweb with default options 57 58```ascii 59meson setup builddir 60ninja -C builddir 61``` 62 63If any of the dependencies are not found on the host system during 64configuration, meson will automatically download them via its wrap dependencies 65mentioned in `bmcweb/subprojects`. 66 67## Use of persistent data 68 69bmcweb relies on some on-system data for storage of persistent data that is 70internal to the process. Details on the exact data stored and when it is 71read/written can seen from the `persistent_data` namespace. 72 73## TLS certificate generation 74 75When SSL support is enabled and a usable certificate is not found, bmcweb will 76generate a self-signed a certificate before launching the server. Please see the 77bmcweb source code for details on the parameters this certificate is built with. 78 79## Compression 80 81bmcweb supports various forms of http compression, including zstd and gzip. 82Client headers are observed to determine whether compressed payloads are 83supported. 84 85## Redfish Aggregation 86 87bmcweb is capable of aggregating resources from satellite BMCs. Refer to 88[AGGREGATION.md](https://github.com/openbmc/bmcweb/blob/master/docs/AGGREGATION.md) 89for more information on how to enable and use this feature. 90