From 6c62b8a8b9d6a8e25c26757b18ba05c63ab4224b Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <borkmann@iogearbox.net>
Date: Mon, 14 May 2012 17:30:47 +0200
Subject: [PATCH] ring: add hw support for mmaped timestamping

Signed-off-by: Daniel Borkmann <borkmann@iogearbox.net>
---
 src/netsniff-ng.c |  2 ++
 src/ring.h        | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)

diff --git a/src/netsniff-ng.c b/src/netsniff-ng.c
index 858996e..1c640bd 100644
--- a/src/netsniff-ng.c
+++ b/src/netsniff-ng.c
@@ -365,6 +365,7 @@ static void enter_mode_pcap_to_tx(struct mode *mode)
 	bpf_parse_rules(mode->filter, &bpf_ops);
 
 	set_packet_loss_discard(tx_sock);
+	set_sockopt_hwtimestamp(tx_sock, mode->device_out);
 	setup_tx_ring_layout(tx_sock, &tx_ring, size, mode->jumbo_support);
 	create_tx_ring(tx_sock, &tx_ring);
 	mmap_tx_ring(tx_sock, &tx_ring);
@@ -862,6 +863,7 @@ try_file:
 	bpf_parse_rules(mode->filter, &bpf_ops);
 	bpf_attach_to_sock(sock, &bpf_ops);
 
+	set_sockopt_hwtimestamp(sock, mode->device_in);
 	setup_rx_ring_layout(sock, &rx_ring, size, mode->jumbo_support);
 	create_rx_ring(sock, &rx_ring);
 	mmap_rx_ring(sock, &rx_ring);
diff --git a/src/ring.h b/src/ring.h
index a6f0bc0..777e84e 100644
--- a/src/ring.h
+++ b/src/ring.h
@@ -16,6 +16,9 @@
 #include <stdio.h>
 #include <stdint.h>
 #include <linux/if_packet.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <sys/ioctl.h>
 #include <string.h>
 #include <poll.h>
 #include <sys/poll.h>
@@ -23,6 +26,7 @@
 #include "xsys.h"
 #include "built_in.h"
 #include "mtrand.h"
+#include "xstring.h"
 #include "die.h"
 
 #ifndef PACKET_FANOUT
@@ -145,4 +149,66 @@ static inline void set_sockopt_fanout(int sock, unsigned int fanout_id,
 		panic("No packet fanout support!\n");
 }
 
+#ifndef PACKET_TIMESTAMP
+enum {
+	SOF_TIMESTAMPING_TX_HARDWARE = (1<<0),
+	SOF_TIMESTAMPING_TX_SOFTWARE = (1<<1),
+	SOF_TIMESTAMPING_RX_HARDWARE = (1<<2),
+	SOF_TIMESTAMPING_RX_SOFTWARE = (1<<3),
+	SOF_TIMESTAMPING_SOFTWARE = (1<<4),
+	SOF_TIMESTAMPING_SYS_HARDWARE = (1<<5),
+	SOF_TIMESTAMPING_RAW_HARDWARE = (1<<6),
+	SOF_TIMESTAMPING_MASK =
+	(SOF_TIMESTAMPING_RAW_HARDWARE - 1) |
+	SOF_TIMESTAMPING_RAW_HARDWARE
+};
+
+struct hwtstamp_config {
+	int flags;
+	int tx_type;
+	int rx_filter;
+};
+
+enum hwtstamp_tx_types {
+	HWTSTAMP_TX_OFF,
+	HWTSTAMP_TX_ON,
+	HWTSTAMP_TX_ONESTEP_SYNC,
+};
+
+enum hwtstamp_rx_filters {
+	HWTSTAMP_FILTER_NONE,
+	HWTSTAMP_FILTER_ALL,
+};
+
+# define PACKET_TIMESTAMP	17
+#else
+# include <linux/net_tstamp.h>
+#endif /* PACKET_TIMESTAMP */
+
+static inline void set_sockopt_hwtimestamp(int sock, char *dev)
+{
+	int timesource, ret;
+	struct hwtstamp_config hwconfig;
+	struct ifreq ifr;
+
+	memset(&hwconfig, 0, sizeof(hwconfig));
+	hwconfig.tx_type = HWTSTAMP_TX_ON;
+	hwconfig.rx_filter = HWTSTAMP_FILTER_ALL;
+
+	memset(&ifr, 0, sizeof(ifr));
+	strlcpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
+	ifr.ifr_data = &hwconfig;
+
+	ret = ioctl(sock, SIOCSHWTSTAMP, &ifr);
+	if (ret < 0)
+		return;
+
+	timesource = SOF_TIMESTAMPING_RAW_HARDWARE;
+
+	ret = setsockopt(sock, SOL_PACKET, PACKET_TIMESTAMP, &timesource,
+			 sizeof(timesource));
+	if (ret)
+		panic("Cannot set timestamping!\n");
+}
+
 #endif /* RING_H */
-- 
2.11.4.GIT