commit	42cbb517ffc573e9ec39077f5a59c1443e0ef9ea	[log] [tgz]
author	Karol Wojciechowski <karol.wojciechowski@intel.com>	Wed Jul 28 17:12:20 2021 +0200
committer	Ed Tanous <ed@tanous.net>	Thu Jul 29 16:23:36 2021 +0000
tree	c8c64963ec299f0932275c1571f7e74e405509fa
parent	7088690c98169f0a8710909560647a560287f8a6 [diff]

HealthPopulate: Fix imprecise matching

This commit resolves https://github.com/openbmc/bmcweb/issues/208
Issue was an example of common error https://github.com/openbmc/bmcweb/issues/12

Current mechanism creates incorrect propagation of health statuses to additional nodes. Dbus paths are matched solely by looking at beginning of their path using boost::starts_with. To make an example on memory health statuses system, that created unwanted one-sided connection of dimms placed on path ".../dimm2" and '.../dimm21'. When status object with path '.../dimm21/warning' appeared, it was altering the health setting on both dimms mentioned, just because their beginning path was in fact matching string-wise. That behaviour needed a change to prevent presented imprecise matching.

This commit adds a check for a slash '/' sign which marks closing of singular path part. Now objects that are compared to their destination paths are guaranteed not to interact with partially cut names where single characters could determine its match. A slash '/' is not required to match to an object if their path is exactly identical (due to paths not being finished by slash) - that is ensured by use of second, alternative match condition checked with boost::equals.

Tested: I used bmcweb's memory mechanism (redfish-core/lib/memory.hpp) to assess that statuses are not being incorrectly propagated anymore after introduction of this commit. All dimm health statuses are presented on redfish. I checked health statuses of example dimms that could be vulnerable to this issue, to be exact dimm10 and dimm1. Then, I proceeded to create an warning status (reverse association object: "warning") association object (https://github.com/openbmc/docs/blob/master/architecture/object-mapper.md#associations) with object path /xyz/openbmc_project/inventory/system/chassis/motherboard/dimm10 so that getAllStatusAssociations() function in redfish-core/lib/health.hpp could find it and apply health status change. By getting the data before and after creating association object prepared for dimm10, the difference was seen only in status of dimm10, which is appropriate to created association. I repeated the process again for dimm22 and dimm2. Observation of health statuses of both dimms in mentioned cases led to trustworthy conclusion - string-wise comparition does not create unwanted propagations anymore.

Signed-off-by: Karol Wojciechowski <karol.wojciechowski@intel.com>
Change-Id: Id5e113373f537afa33dc206ed9e2e90598e23f8f

redfish-core/lib/health.hpp[diff]

1 file changed

tree: c8c64963ec299f0932275c1571f7e74e405509fa

README.md

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.