[dpdk-dev] [PATCH] app/testpmd: swap mac in IEEE1588 forwarding

[Pablo de Lara]

IEEE1588 forwarding mode uses same port to receive and transmit packets.
In this mode, the MAC address in the packets are not touched,
and therefore, packets could be sent with the same destination
MAC address as the MAC address of the port that is transmitting,
which causes the packet to be dropped in some NICs.

In order to avoid this scenario, MAC addresses are swapped
before packet is sent out.

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch at intel.com>
---
 app/test-pmd/ieee1588fwd.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/app/test-pmd/ieee1588fwd.c b/app/test-pmd/ieee1588fwd.c
index c69023a..0d3b37a 100644
--- a/app/test-pmd/ieee1588fwd.c
+++ b/app/test-pmd/ieee1588fwd.c
@@ -123,6 +123,7 @@ ieee1588_packet_fwd(struct fwd_stream *fs)
 {
 	struct rte_mbuf  *mb;
 	struct ether_hdr *eth_hdr;
+	struct ether_addr addr;
 	struct ptpv2_msg *ptp_hdr;
 	uint16_t eth_type;
 	uint32_t timesync_index;
@@ -205,6 +206,11 @@ ieee1588_packet_fwd(struct fwd_stream *fs)
 	/* Read and check the RX timestamp. */
 	port_ieee1588_rx_timestamp_check(fs->rx_port, timesync_index);
 
+	/* Swap dest and src mac addresses. */
+	ether_addr_copy(&eth_hdr->d_addr, &addr);
+	ether_addr_copy(&eth_hdr->s_addr, &eth_hdr->d_addr);
+	ether_addr_copy(&addr, &eth_hdr->s_addr);
+
 	/* Forward PTP packet with hardware TX timestamp */
 	mb->ol_flags |= PKT_TX_IEEE1588_TMST;
 	fs->tx_packets += 1;
-- 
2.5.0