[dpdk-dev] [PATCH v2 0/5] add dpdk packet capture support for tcpdump

[Reshma Pattan <reshma.pattan@intel.com>]

This patch set include design to capture dpdk port packets for tcpdump.

This patch set include test-pmd changes to verify patch set given in Dependencies 1.

Current  patch set is dependent on below patch set. Below patch set must be applied before applying current patch set.

Dependencies 1:
http://dpdk.org/dev/patchwork/patch/9750/
http://dpdk.org/dev/patchwork/patch/9751/
http://dpdk.org/dev/patchwork/patch/9752/

Dependencies 2:
Patches 2/5 and 3/5 of current patch set contains pcap based design.
So to run and compile these patches, libpcap must be installed and pcap config option should be set to yes i.e. CONFIG_RTE_LIBRTE_PMD_PCAP=y.

packet capture flow for tcpdump:
================================
Part of design is implemented in secondary process (proc_info.c) and some part in primary process (eal_interrupt.c).

Communication between both the processes is provided using socket and rte_ring.

[Secondary process:]
*Changes are included in patch 3/5

*User should request packet capture via proc_info app command line with port, queue and src ip filter information.

Note: As initial development basic src filter option only provided.

*proc_info sends port, queue and src ip filter information to primary along with register rx tx cbs message.

*proc_info creates  two pcap devices for writing ingress and egress packets of port and queue.

*Runs in a while loop, dequeue packets sent by primary over shared rte_ring and writes to respective pcap files.

[Primary Process]:
*Changes are included in patch 4/5.

*Create rte_rings and mempool used for communicating packets with secondary.

*Create socket, waits on socket for message from secondary.

*Upon receiving the register rx tx cbs message, registers rte_eth_rxtx_callbacks for receiving ingress and egress packets of given port and queue.

*RX callback:
    Gets packet, apply src ip filter, for matched packets, duplicate packets will be
    created from mempool and new duplicated packets will be enqueued to
    rte_ring for secondary to dequeue and write to pcap.

*TX callback:
    Gets packets, apply src ip filter, for matched packets increments reference
    counter of the packet, enqueue to other rte_ring for secondary to dequeue and
    write to pcap.

[Secondary Process]:
*When secondary is terminated with ctrl+c, secondary sends remove rx tx cbs message to primary.

*[Primary Process]:
*When primary receives remove rx tx cbs message should take care of removing registered rxtx callbacks.

Users who wish to view packets can run "tcpdump -r RX_pcap.pcap/TX_pcap.pcap"
to view packets of interest.

Running the changes:
===================
1)Start any primary sample application.
ex:sudo ./examples/rxtx_callbacks/build/rxtx_callbacks -c 0x2 -n 2

2)Start proc_info(runs as secondary process by default)application with new parameters for tcpdump.
ex: sudo ./build/app/proc_info/dpdk_proc_info -c 0x4 -n 2 -- -p 0x3 --tcpdump '(0,0)(1,0)' --src-ip-filter="2.2.2.2"

3)Start traffic from traffic generator.

4)Now you can view ingress and egress packets of dpdk ports matching src-ip-filter written to /tmp/RX_pcap.pcap  and /tmp/TX_pcap.pcap respectively.

5)Stop the secondary process using ctrl+c and rerun it and packet capturing should resume again.

Note: Writing to PCAP files will be stopped once the folder size where pcap files exists reaches its max value.

v2:
* extended nb_rxq/nb_txq check to other fwd modes along with rx_only and tx_only.
* changed some of the global variables to static in proc_info/main.c and eal_interrupts.c.
* release notes updated.

Reshma Pattan (5):
  app/test-pmd: fix nb_rxq and np_txq checks
  drivers/net/pcap: add public api to create pcap device
  app/proc_info: add tcpdump support in secondary process
  lib/librte_eal: add tcpdump support in primary process
  doc: update doc for tcpdump feature

 app/proc_info/main.c                         |  451 +++++++++++++++++++++++++-
 app/test-pmd/cmdline.c                       |   11 +-
 app/test-pmd/parameters.c                    |   14 +-
 app/test-pmd/testpmd.c                       |   28 ++-
 doc/guides/rel_notes/release_16_04.rst       |    9 +-
 drivers/net/pcap/Makefile                    |    4 +-
 drivers/net/pcap/rte_eth_pcap.c              |  156 ++++++++-
 drivers/net/pcap/rte_eth_pcap.h              |   87 +++++
 drivers/net/pcap/rte_pmd_pcap_version.map    |    8 +
 lib/librte_eal/linuxapp/eal/Makefile         |    5 +-
 lib/librte_eal/linuxapp/eal/eal_interrupts.c |  375 +++++++++++++++++++++-
 11 files changed, 1105 insertions(+), 43 deletions(-)
 create mode 100644 drivers/net/pcap/rte_eth_pcap.h

-- 
1.7.4.1