[RFC 0/4] alternative capture mechanism

[Stephen Hemminger <stephen@networkplumber.org>]

This is an RFC for an alternative way to capture packets from a DPDK
application. I did brief demo of similar mechanism at DPDK summit but
this is more complete. Capture runs in the primary process and is driven
entirely over telemetry; no secondary process is involved.

A client asks the application to start capturing and passes it a file
descriptor to write to. The application writes pcapng to that descriptor.
A Wireshark extcap script is the intended front end, but the control path
is just telemetry and the output is just a pipe, so other front ends are
possible.

  1/4  telemetry: let a command receive file descriptors from the client
  2/4  capture: the library
  3/4  test: functional test
  4/4  app: the Wireshark extcap script and its documentation

Setup and usage are in doc/guides/tools/wireshark_extcap.rst.

Primary process only for now; secondary-process capture is possible as
follow-on. Posting as RFC to get feedback on the approach.

The extcap script is dual licensed (BSD-3-Clause OR GPL-2.0-or-later) as
it may be more useful in the Wireshark tree.

Stephen Hemminger (4):
  telemetry: allow commands to receive file descriptors
  capture: infrastructure wireshark packet capture
  test: add test for capture hooks
  usertools/dpdk-wireshark-extcap.py: script for external capture

 MAINTAINERS                            |   4 +
 app/test/meson.build                   |   1 +
 app/test/test_capture.c                | 365 +++++++++++
 doc/guides/rel_notes/release_26_07.rst |  12 +
 doc/guides/tools/index.rst             |   1 +
 doc/guides/tools/wireshark_extcap.rst  | 155 +++++
 lib/capture/capture.c                  | 821 +++++++++++++++++++++++++
 lib/capture/capture_impl.h             |  56 ++
 lib/capture/filter.c                   | 108 ++++
 lib/capture/meson.build                |  19 +
 lib/meson.build                        |   1 +
 lib/telemetry/rte_telemetry.h          |  66 ++
 lib/telemetry/telemetry.c              | 115 +++-
 usertools/dpdk-wireshark-extcap.py     | 274 +++++++++
 14 files changed, 1986 insertions(+), 12 deletions(-)
 create mode 100644 app/test/test_capture.c
 create mode 100644 doc/guides/tools/wireshark_extcap.rst
 create mode 100644 lib/capture/capture.c
 create mode 100644 lib/capture/capture_impl.h
 create mode 100644 lib/capture/filter.c
 create mode 100644 lib/capture/meson.build
 create mode 100755 usertools/dpdk-wireshark-extcap.py

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2.53.0