This series adds live packet capture from a running DPDK application over the
telemetry socket. A new capture library installs Rx/Tx callbacks on an ethdev
port and writes pcapng to a FIFO, with an optional libpcap filter and
per-queue selection. A helper program presents those ports to Wireshark as
capture interfaces.
Advantages of this:
- no secondary process needed to capture
- installation is just putting the helper in the Wireshark extcap directory
- the helper has no dependency on DPDK libraries; can be packaged with
Wireshark
- allows for live capture
- supports BPF (with JIT) for filtering
How it works:
- The capture library registers telemetry commands (/ethdev/capture/*)
- Callbacks are installed on the specified port/queues to copy packets
- Packets are formatted as pcapng and written to the specified output
- No packet data passes through the telemetry socket itself
Packets handled by a secondary process are captured too, using EAL IPC as
pdump does.
The helper is a C program so that it can be installed with privilege, which
is what lets Wireshark capture from a root application without itself running
as root. See doc/guides/tools/wireshark_extcap.rst.
Linux and FreeBSD only. Windows needs the transport first: telemetry has no
socket server there and uses SOCK_SEQPACKET, which Windows AF_UNIX lacks.
A stream socket would need the replies framed.
Testing:
- dpdk-wireshark-extcap --extcap-interfaces lists the ports. Reasons for an
empty list go to stderr, which the Wireshark GUI hides.
- Unit tests are in app/test/test_capture.c
- Tested on Linux capturing from a root application as a non-root user.
The unit test also passes on FreeBSD.
v4
- helper rewritten in C, and can be installed with privilege so Wireshark
need not run as the same user as the DPDK application
- capture packets handled by secondary processes
- split the library into several files by area
- dropped the pcapng change adding the filter-accepted count to the
interface statistics block. Still reported through telemetry.
v3 - fixed AI review feedback
Stephen Hemminger (3):
capture: infrastructure wireshark packet capture
test: add test for capture hooks
usertools: add script for wireshark capture
MAINTAINERS | 4 +
app/test/meson.build | 1 +
app/test/test_capture.c | 688 ++++++++++++++
doc/guides/prog_guide/capture_lib.rst | 167 ++++
doc/guides/prog_guide/index.rst | 1 +
doc/guides/rel_notes/release_26_11.rst | 5 +
doc/guides/tools/index.rst | 1 +
doc/guides/tools/wireshark_extcap.rst | 198 ++++
lib/capture/capture.c | 560 ++++++++++++
lib/capture/datapath.c | 420 +++++++++
lib/capture/filter.c | 180 ++++
lib/capture/meson.build | 24 +
lib/capture/multiproc.c | 246 +++++
lib/capture/output.c | 294 ++++++
lib/capture/private.h | 214 +++++
lib/meson.build | 1 +
usertools/dpdk-wireshark-extcap.c | 1145 ++++++++++++++++++++++++
usertools/meson.build | 23 +
18 files changed, 4172 insertions(+)
create mode 100644 app/test/test_capture.c
create mode 100644 doc/guides/prog_guide/capture_lib.rst
create mode 100644 doc/guides/tools/wireshark_extcap.rst
create mode 100644 lib/capture/capture.c
create mode 100644 lib/capture/datapath.c
create mode 100644 lib/capture/filter.c
create mode 100644 lib/capture/meson.build
create mode 100644 lib/capture/multiproc.c
create mode 100644 lib/capture/output.c
create mode 100644 lib/capture/private.h
create mode 100644 usertools/dpdk-wireshark-extcap.c
--
2.53.0
