summary refs log tree commit diff
path: root/Documentation/networking/timestamping/timestamping.c
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/networking/timestamping/timestamping.c')
-rw-r--r--Documentation/networking/timestamping/timestamping.c533
1 files changed, 533 insertions, 0 deletions
diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
new file mode 100644
index 000000000000..43d143104210
--- /dev/null
+++ b/Documentation/networking/timestamping/timestamping.c
@@ -0,0 +1,533 @@
+/*
+ * This program demonstrates how the various time stamping features in
+ * the Linux kernel work. It emulates the behavior of a PTP
+ * implementation in stand-alone master mode by sending PTPv1 Sync
+ * multicasts once every second. It looks for similar packets, but
+ * beyond that doesn't actually implement PTP.
+ *
+ * Outgoing packets are time stamped with SO_TIMESTAMPING with or
+ * without hardware support.
+ *
+ * Incoming packets are time stamped with SO_TIMESTAMPING with or
+ * without hardware support, SIOCGSTAMP[NS] (per-socket time stamp) and
+ * SO_TIMESTAMP[NS].
+ *
+ * Copyright (C) 2009 Intel Corporation.
+ * Author: Patrick Ohly <patrick.ohly@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <sys/select.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+
+#include "asm/types.h"
+#include "linux/net_tstamp.h"
+#include "linux/errqueue.h"
+
+#ifndef SO_TIMESTAMPING
+# define SO_TIMESTAMPING         37
+# define SCM_TIMESTAMPING        SO_TIMESTAMPING
+#endif
+
+#ifndef SO_TIMESTAMPNS
+# define SO_TIMESTAMPNS 35
+#endif
+
+#ifndef SIOCGSTAMPNS
+# define SIOCGSTAMPNS 0x8907
+#endif
+
+#ifndef SIOCSHWTSTAMP
+# define SIOCSHWTSTAMP 0x89b0
+#endif
+
+static void usage(const char *error)
+{
+	if (error)
+		printf("invalid option: %s\n", error);
+	printf("timestamping interface option*\n\n"
+	       "Options:\n"
+	       "  IP_MULTICAST_LOOP - looping outgoing multicasts\n"
+	       "  SO_TIMESTAMP - normal software time stamping, ms resolution\n"
+	       "  SO_TIMESTAMPNS - more accurate software time stamping\n"
+	       "  SOF_TIMESTAMPING_TX_HARDWARE - hardware time stamping of outgoing packets\n"
+	       "  SOF_TIMESTAMPING_TX_SOFTWARE - software fallback for outgoing packets\n"
+	       "  SOF_TIMESTAMPING_RX_HARDWARE - hardware time stamping of incoming packets\n"
+	       "  SOF_TIMESTAMPING_RX_SOFTWARE - software fallback for incoming packets\n"
+	       "  SOF_TIMESTAMPING_SOFTWARE - request reporting of software time stamps\n"
+	       "  SOF_TIMESTAMPING_SYS_HARDWARE - request reporting of transformed HW time stamps\n"
+	       "  SOF_TIMESTAMPING_RAW_HARDWARE - request reporting of raw HW time stamps\n"
+	       "  SIOCGSTAMP - check last socket time stamp\n"
+	       "  SIOCGSTAMPNS - more accurate socket time stamp\n");
+	exit(1);
+}
+
+static void bail(const char *error)
+{
+	printf("%s: %s\n", error, strerror(errno));
+	exit(1);
+}
+
+static const unsigned char sync[] = {
+	0x00, 0x01, 0x00, 0x01,
+	0x5f, 0x44, 0x46, 0x4c,
+	0x54, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00,
+	0x01, 0x01,
+
+	/* fake uuid */
+	0x00, 0x01,
+	0x02, 0x03, 0x04, 0x05,
+
+	0x00, 0x01, 0x00, 0x37,
+	0x00, 0x00, 0x00, 0x08,
+	0x00, 0x00, 0x00, 0x00,
+	0x49, 0x05, 0xcd, 0x01,
+	0x29, 0xb1, 0x8d, 0xb0,
+	0x00, 0x00, 0x00, 0x00,
+	0x00, 0x01,
+
+	/* fake uuid */
+	0x00, 0x01,
+	0x02, 0x03, 0x04, 0x05,
+
+	0x00, 0x00, 0x00, 0x37,
+	0x00, 0x00, 0x00, 0x04,
+	0x44, 0x46, 0x4c, 0x54,
+	0x00, 0x00, 0xf0, 0x60,
+	0x00, 0x01, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x01,
+	0x00, 0x00, 0xf0, 0x60,
+	0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x04,
+	0x44, 0x46, 0x4c, 0x54,
+	0x00, 0x01,
+
+	/* fake uuid */
+	0x00, 0x01,
+	0x02, 0x03, 0x04, 0x05,
+
+	0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00
+};
+
+static void sendpacket(int sock, struct sockaddr *addr, socklen_t addr_len)
+{
+	struct timeval now;
+	int res;
+
+	res = sendto(sock, sync, sizeof(sync), 0,
+		addr, addr_len);
+	gettimeofday(&now, 0);
+	if (res < 0)
+		printf("%s: %s\n", "send", strerror(errno));
+	else
+		printf("%ld.%06ld: sent %d bytes\n",
+		       (long)now.tv_sec, (long)now.tv_usec,
+		       res);
+}
+
+static void printpacket(struct msghdr *msg, int res,
+			char *data,
+			int sock, int recvmsg_flags,
+			int siocgstamp, int siocgstampns)
+{
+	struct sockaddr_in *from_addr = (struct sockaddr_in *)msg->msg_name;
+	struct cmsghdr *cmsg;
+	struct timeval tv;
+	struct timespec ts;
+	struct timeval now;
+
+	gettimeofday(&now, 0);
+
+	printf("%ld.%06ld: received %s data, %d bytes from %s, %d bytes control messages\n",
+	       (long)now.tv_sec, (long)now.tv_usec,
+	       (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular",
+	       res,
+	       inet_ntoa(from_addr->sin_addr),
+	       msg->msg_controllen);
+	for (cmsg = CMSG_FIRSTHDR(msg);
+	     cmsg;
+	     cmsg = CMSG_NXTHDR(msg, cmsg)) {
+		printf("   cmsg len %d: ", cmsg->cmsg_len);
+		switch (cmsg->cmsg_level) {
+		case SOL_SOCKET:
+			printf("SOL_SOCKET ");
+			switch (cmsg->cmsg_type) {
+			case SO_TIMESTAMP: {
+				struct timeval *stamp =
+					(struct timeval *)CMSG_DATA(cmsg);
+				printf("SO_TIMESTAMP %ld.%06ld",
+				       (long)stamp->tv_sec,
+				       (long)stamp->tv_usec);
+				break;
+			}
+			case SO_TIMESTAMPNS: {
+				struct timespec *stamp =
+					(struct timespec *)CMSG_DATA(cmsg);
+				printf("SO_TIMESTAMPNS %ld.%09ld",
+				       (long)stamp->tv_sec,
+				       (long)stamp->tv_nsec);
+				break;
+			}
+			case SO_TIMESTAMPING: {
+				struct timespec *stamp =
+					(struct timespec *)CMSG_DATA(cmsg);
+				printf("SO_TIMESTAMPING ");
+				printf("SW %ld.%09ld ",
+				       (long)stamp->tv_sec,
+				       (long)stamp->tv_nsec);
+				stamp++;
+				printf("HW transformed %ld.%09ld ",
+				       (long)stamp->tv_sec,
+				       (long)stamp->tv_nsec);
+				stamp++;
+				printf("HW raw %ld.%09ld",
+				       (long)stamp->tv_sec,
+				       (long)stamp->tv_nsec);
+				break;
+			}
+			default:
+				printf("type %d", cmsg->cmsg_type);
+				break;
+			}
+			break;
+		case IPPROTO_IP:
+			printf("IPPROTO_IP ");
+			switch (cmsg->cmsg_type) {
+			case IP_RECVERR: {
+				struct sock_extended_err *err =
+					(struct sock_extended_err *)CMSG_DATA(cmsg);
+				printf("IP_RECVERR ee_errno '%s' ee_origin %d => %s",
+					strerror(err->ee_errno),
+					err->ee_origin,
+#ifdef SO_EE_ORIGIN_TIMESTAMPING
+					err->ee_origin == SO_EE_ORIGIN_TIMESTAMPING ?
+					"bounced packet" : "unexpected origin"
+#else
+					"probably SO_EE_ORIGIN_TIMESTAMPING"
+#endif
+					);
+				if (res < sizeof(sync))
+					printf(" => truncated data?!");
+				else if (!memcmp(sync, data + res - sizeof(sync),
+							sizeof(sync)))
+					printf(" => GOT OUR DATA BACK (HURRAY!)");
+				break;
+			}
+			case IP_PKTINFO: {
+				struct in_pktinfo *pktinfo =
+					(struct in_pktinfo *)CMSG_DATA(cmsg);
+				printf("IP_PKTINFO interface index %u",
+					pktinfo->ipi_ifindex);
+				break;
+			}
+			default:
+				printf("type %d", cmsg->cmsg_type);
+				break;
+			}
+			break;
+		default:
+			printf("level %d type %d",
+				cmsg->cmsg_level,
+				cmsg->cmsg_type);
+			break;
+		}
+		printf("\n");
+	}
+
+	if (siocgstamp) {
+		if (ioctl(sock, SIOCGSTAMP, &tv))
+			printf("   %s: %s\n", "SIOCGSTAMP", strerror(errno));
+		else
+			printf("SIOCGSTAMP %ld.%06ld\n",
+			       (long)tv.tv_sec,
+			       (long)tv.tv_usec);
+	}
+	if (siocgstampns) {
+		if (ioctl(sock, SIOCGSTAMPNS, &ts))
+			printf("   %s: %s\n", "SIOCGSTAMPNS", strerror(errno));
+		else
+			printf("SIOCGSTAMPNS %ld.%09ld\n",
+			       (long)ts.tv_sec,
+			       (long)ts.tv_nsec);
+	}
+}
+
+static void recvpacket(int sock, int recvmsg_flags,
+		       int siocgstamp, int siocgstampns)
+{
+	char data[256];
+	struct msghdr msg;
+	struct iovec entry;
+	struct sockaddr_in from_addr;
+	struct {
+		struct cmsghdr cm;
+		char control[512];
+	} control;
+	int res;
+
+	memset(&msg, 0, sizeof(msg));
+	msg.msg_iov = &entry;
+	msg.msg_iovlen = 1;
+	entry.iov_base = data;
+	entry.iov_len = sizeof(data);
+	msg.msg_name = (caddr_t)&from_addr;
+	msg.msg_namelen = sizeof(from_addr);
+	msg.msg_control = &control;
+	msg.msg_controllen = sizeof(control);
+
+	res = recvmsg(sock, &msg, recvmsg_flags|MSG_DONTWAIT);
+	if (res < 0) {
+		printf("%s %s: %s\n",
+		       "recvmsg",
+		       (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular",
+		       strerror(errno));
+	} else {
+		printpacket(&msg, res, data,
+			    sock, recvmsg_flags,
+			    siocgstamp, siocgstampns);
+	}
+}
+
+int main(int argc, char **argv)
+{
+	int so_timestamping_flags = 0;
+	int so_timestamp = 0;
+	int so_timestampns = 0;
+	int siocgstamp = 0;
+	int siocgstampns = 0;
+	int ip_multicast_loop = 0;
+	char *interface;
+	int i;
+	int enabled = 1;
+	int sock;
+	struct ifreq device;
+	struct ifreq hwtstamp;
+	struct hwtstamp_config hwconfig, hwconfig_requested;
+	struct sockaddr_in addr;
+	struct ip_mreq imr;
+	struct in_addr iaddr;
+	int val;
+	socklen_t len;
+	struct timeval next;
+
+	if (argc < 2)
+		usage(0);
+	interface = argv[1];
+
+	for (i = 2; i < argc; i++) {
+		if (!strcasecmp(argv[i], "SO_TIMESTAMP"))
+			so_timestamp = 1;
+		else if (!strcasecmp(argv[i], "SO_TIMESTAMPNS"))
+			so_timestampns = 1;
+		else if (!strcasecmp(argv[i], "SIOCGSTAMP"))
+			siocgstamp = 1;
+		else if (!strcasecmp(argv[i], "SIOCGSTAMPNS"))
+			siocgstampns = 1;
+		else if (!strcasecmp(argv[i], "IP_MULTICAST_LOOP"))
+			ip_multicast_loop = 1;
+		else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_HARDWARE"))
+			so_timestamping_flags |= SOF_TIMESTAMPING_TX_HARDWARE;
+		else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_SOFTWARE"))
+			so_timestamping_flags |= SOF_TIMESTAMPING_TX_SOFTWARE;
+		else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_HARDWARE"))
+			so_timestamping_flags |= SOF_TIMESTAMPING_RX_HARDWARE;
+		else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_SOFTWARE"))
+			so_timestamping_flags |= SOF_TIMESTAMPING_RX_SOFTWARE;
+		else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_SOFTWARE"))
+			so_timestamping_flags |= SOF_TIMESTAMPING_SOFTWARE;
+		else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_SYS_HARDWARE"))
+			so_timestamping_flags |= SOF_TIMESTAMPING_SYS_HARDWARE;
+		else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RAW_HARDWARE"))
+			so_timestamping_flags |= SOF_TIMESTAMPING_RAW_HARDWARE;
+		else
+			usage(argv[i]);
+	}
+
+	sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (socket < 0)
+		bail("socket");
+
+	memset(&device, 0, sizeof(device));
+	strncpy(device.ifr_name, interface, sizeof(device.ifr_name));
+	if (ioctl(sock, SIOCGIFADDR, &device) < 0)
+		bail("getting interface IP address");
+
+	memset(&hwtstamp, 0, sizeof(hwtstamp));
+	strncpy(hwtstamp.ifr_name, interface, sizeof(hwtstamp.ifr_name));
+	hwtstamp.ifr_data = (void *)&hwconfig;
+	memset(&hwconfig, 0, sizeof(&hwconfig));
+	hwconfig.tx_type =
+		(so_timestamping_flags & SOF_TIMESTAMPING_TX_HARDWARE) ?
+		HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
+	hwconfig.rx_filter =
+		(so_timestamping_flags & SOF_TIMESTAMPING_RX_HARDWARE) ?
+		HWTSTAMP_FILTER_PTP_V1_L4_SYNC : HWTSTAMP_FILTER_NONE;
+	hwconfig_requested = hwconfig;
+	if (ioctl(sock, SIOCSHWTSTAMP, &hwtstamp) < 0) {
+		if ((errno == EINVAL || errno == ENOTSUP) &&
+		    hwconfig_requested.tx_type == HWTSTAMP_TX_OFF &&
+		    hwconfig_requested.rx_filter == HWTSTAMP_FILTER_NONE)
+			printf("SIOCSHWTSTAMP: disabling hardware time stamping not possible\n");
+		else
+			bail("SIOCSHWTSTAMP");
+	}
+	printf("SIOCSHWTSTAMP: tx_type %d requested, got %d; rx_filter %d requested, got %d\n",
+	       hwconfig_requested.tx_type, hwconfig.tx_type,
+	       hwconfig_requested.rx_filter, hwconfig.rx_filter);
+
+	/* bind to PTP port */
+	addr.sin_family = AF_INET;
+	addr.sin_addr.s_addr = htonl(INADDR_ANY);
+	addr.sin_port = htons(319 /* PTP event port */);
+	if (bind(sock,
+		 (struct sockaddr *)&addr,
+		 sizeof(struct sockaddr_in)) < 0)
+		bail("bind");
+
+	/* set multicast group for outgoing packets */
+	inet_aton("224.0.1.130", &iaddr); /* alternate PTP domain 1 */
+	addr.sin_addr = iaddr;
+	imr.imr_multiaddr.s_addr = iaddr.s_addr;
+	imr.imr_interface.s_addr =
+		((struct sockaddr_in *)&device.ifr_addr)->sin_addr.s_addr;
+	if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF,
+		       &imr.imr_interface.s_addr, sizeof(struct in_addr)) < 0)
+		bail("set multicast");
+
+	/* join multicast group, loop our own packet */
+	if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,
+		       &imr, sizeof(struct ip_mreq)) < 0)
+		bail("join multicast group");
+
+	if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_LOOP,
+		       &ip_multicast_loop, sizeof(enabled)) < 0) {
+		bail("loop multicast");
+	}
+
+	/* set socket options for time stamping */
+	if (so_timestamp &&
+		setsockopt(sock, SOL_SOCKET, SO_TIMESTAMP,
+			   &enabled, sizeof(enabled)) < 0)
+		bail("setsockopt SO_TIMESTAMP");
+
+	if (so_timestampns &&
+		setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS,
+			   &enabled, sizeof(enabled)) < 0)
+		bail("setsockopt SO_TIMESTAMPNS");
+
+	if (so_timestamping_flags &&
+		setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING,
+			   &so_timestamping_flags,
+			   sizeof(so_timestamping_flags)) < 0)
+		bail("setsockopt SO_TIMESTAMPING");
+
+	/* request IP_PKTINFO for debugging purposes */
+	if (setsockopt(sock, SOL_IP, IP_PKTINFO,
+		       &enabled, sizeof(enabled)) < 0)
+		printf("%s: %s\n", "setsockopt IP_PKTINFO", strerror(errno));
+
+	/* verify socket options */
+	len = sizeof(val);
+	if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMP, &val, &len) < 0)
+		printf("%s: %s\n", "getsockopt SO_TIMESTAMP", strerror(errno));
+	else
+		printf("SO_TIMESTAMP %d\n", val);
+
+	if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS, &val, &len) < 0)
+		printf("%s: %s\n", "getsockopt SO_TIMESTAMPNS",
+		       strerror(errno));
+	else
+		printf("SO_TIMESTAMPNS %d\n", val);
+
+	if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING, &val, &len) < 0) {
+		printf("%s: %s\n", "getsockopt SO_TIMESTAMPING",
+		       strerror(errno));
+	} else {
+		printf("SO_TIMESTAMPING %d\n", val);
+		if (val != so_timestamping_flags)
+			printf("   not the expected value %d\n",
+			       so_timestamping_flags);
+	}
+
+	/* send packets forever every five seconds */
+	gettimeofday(&next, 0);
+	next.tv_sec = (next.tv_sec + 1) / 5 * 5;
+	next.tv_usec = 0;
+	while (1) {
+		struct timeval now;
+		struct timeval delta;
+		long delta_us;
+		int res;
+		fd_set readfs, errorfs;
+
+		gettimeofday(&now, 0);
+		delta_us = (long)(next.tv_sec - now.tv_sec) * 1000000 +
+			(long)(next.tv_usec - now.tv_usec);
+		if (delta_us > 0) {
+			/* continue waiting for timeout or data */
+			delta.tv_sec = delta_us / 1000000;
+			delta.tv_usec = delta_us % 1000000;
+
+			FD_ZERO(&readfs);
+			FD_ZERO(&errorfs);
+			FD_SET(sock, &readfs);
+			FD_SET(sock, &errorfs);
+			printf("%ld.%06ld: select %ldus\n",
+			       (long)now.tv_sec, (long)now.tv_usec,
+			       delta_us);
+			res = select(sock + 1, &readfs, 0, &errorfs, &delta);
+			gettimeofday(&now, 0);
+			printf("%ld.%06ld: select returned: %d, %s\n",
+			       (long)now.tv_sec, (long)now.tv_usec,
+			       res,
+			       res < 0 ? strerror(errno) : "success");
+			if (res > 0) {
+				if (FD_ISSET(sock, &readfs))
+					printf("ready for reading\n");
+				if (FD_ISSET(sock, &errorfs))
+					printf("has error\n");
+				recvpacket(sock, 0,
+					   siocgstamp,
+					   siocgstampns);
+				recvpacket(sock, MSG_ERRQUEUE,
+					   siocgstamp,
+					   siocgstampns);
+			}
+		} else {
+			/* write one packet */
+			sendpacket(sock,
+				   (struct sockaddr *)&addr,
+				   sizeof(addr));
+			next.tv_sec += 5;
+			continue;
+		}
+	}
+
+	return 0;
+}