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gerrit.openbmc.org / openbmc / bmcweb / 5238bd3205c61efa4ff82c0c5a4eb9d594a0865b
commit5238bd3205c61efa4ff82c0c5a4eb9d594a0865b[log] [tgz]
authorAppaRao Puli <apparao.puli@linux.intel.com>Tue Nov 17 11:03:11 2020 +0530
committerAppaRao Puli <apparao.puli@linux.intel.com>Tue Nov 17 11:03:11 2020 +0530
treebfd821d1437095db1cc6f6c3746afb42abb86b29
parent929d4b57f10bc4200e16b71fbcf32521d8cc23c1 [diff]
fix bmcweb crash during sol communication

After establishing the obmc_console socket
communication, If client closes the connection
abruptly, async read/write operation fails with
asio.ssl.stream error. To handle the error, it calls
closeHandler call back function and cleans the session
and socket. Any ongoing async read operation should
be discarded by checking socket handle. Read/Write the
message from stream via async_read_some()/async_write
without checking socket handle, causes the crash.
Added socket handle validation before performing any
read/write operation to avoid crash.

Tested:
 - Without fix, when sol connection closes abruptly, at times
   saw the crash with below logs.
Nov 13 11:32:51 intel-obmc bmcweb[20169]: doRead error asio.ssl.stream:1
Nov 13 11:32:51 intel-obmc systemd[1]: bmcweb.service: Main process exited, code=dumped, status=11/SEGV
Nov 13 11:32:51 intel-obmc systemd[1]: bmcweb.service: Failed with result 'core-dump'.

 - With fix, verified the case and no crashes seen.
Nov 13 12:55:04 intel-obmc bmcweb[24426]: (2020-11-13 12:55:04) [ERROR "websocket.h":207] doRead error asio.ssl.stream:1
Nov 13 12:55:04 intel-obmc bmcweb[24426]: (2020-11-13 12:55:04) [ERROR "obmc_console.hpp":67] doread() - Socket closed

Signed-off-by: AppaRao Puli <apparao.puli@linux.intel.com>
Change-Id: I2afda509ca77a561651a8682e042c45ca7366642
1 file changed
tree: bfd821d1437095db1cc6f6c3746afb42abb86b29
  1. http/
  2. include/
  3. redfish-core/
  4. scripts/
  5. src/
  6. static/
  7. subprojects/
  8. .clang-format
  9. .clang-ignore
  10. .clang-tidy
  11. .dockerignore
  12. .gitignore
  13. .shellcheck
  14. bmcweb.service.in
  15. bmcweb.socket
  16. build_x86.sh
  17. build_x86_docker.sh
  18. COMMON_ERRORS.md
  19. DEVELOPING.md
  20. Dockerfile
  21. Dockerfile.base
  22. JenkinsFile
  23. LICENCE
  24. MAINTAINERS
  25. meson.build
  26. meson_options.txt
  27. pam-webserver
  28. README.md
  29. Redfish.md
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

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.