Merge branch 'ping6-cmsg'

Jakub Kicinski says:

====================
net: ping6: support basic socket cmsgs

Add support for common SOL_SOCKET cmsgs in ICMPv6 sockets.
Extend the cmsg tests to cover more cmsgs and socket types.

SOL_IPV6 cmsgs to follow.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ping.c

@@ -59,8 +59,6 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	struct pingfakehdr pfh;
 	struct ipcm6_cookie ipc6;
 
-	pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
-
 	err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
 				  sizeof(user_icmph));
 	if (err)
@@ -99,6 +97,14 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	    (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if))
 		return -EINVAL;
 
+	ipcm6_init_sk(&ipc6, np);
+	ipc6.sockc.tsflags = sk->sk_tsflags;
+	ipc6.sockc.mark = sk->sk_mark;
+
+	err = sock_cmsg_send(sk, msg, &ipc6.sockc);
+	if (err)
+		return err;
+
 	/* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 
 	memset(&fl6, 0, sizeof(fl6));
@@ -107,14 +113,12 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	fl6.saddr = np->saddr;
 	fl6.daddr = *daddr;
 	fl6.flowi6_oif = oif;
-	fl6.flowi6_mark = sk->sk_mark;
+	fl6.flowi6_mark = ipc6.sockc.mark;
 	fl6.flowi6_uid = sk->sk_uid;
 	fl6.fl6_icmp_type = user_icmph.icmp6_type;
 	fl6.fl6_icmp_code = user_icmph.icmp6_code;
 	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
 
-	ipcm6_init_sk(&ipc6, np);
-	ipc6.sockc.mark = sk->sk_mark;
 	fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
 
 	dst = ip6_sk_dst_lookup_flow(sk, &fl6, daddr, false);

tools/testing/selftests/net/.gitignore

@@ -35,4 +35,4 @@ test_unix_oob
 gro
 ioam6_parser
 toeplitz
-cmsg_so_mark
+cmsg_sender

tools/testing/selftests/net/Makefile

@@ -30,6 +30,7 @@ TEST_PROGS += ioam6.sh
 TEST_PROGS += gro.sh
 TEST_PROGS += gre_gso.sh
 TEST_PROGS += cmsg_so_mark.sh
+TEST_PROGS += cmsg_time.sh
 TEST_PROGS += srv6_end_dt46_l3vpn_test.sh
 TEST_PROGS += srv6_end_dt4_l3vpn_test.sh
 TEST_PROGS += srv6_end_dt6_l3vpn_test.sh
@@ -52,7 +53,7 @@ TEST_GEN_FILES += gro
 TEST_GEN_PROGS = reuseport_bpf reuseport_bpf_cpu reuseport_bpf_numa
 TEST_GEN_PROGS += reuseport_dualstack reuseaddr_conflict tls
 TEST_GEN_FILES += toeplitz
-TEST_GEN_FILES += cmsg_so_mark
+TEST_GEN_FILES += cmsg_sender
 
 TEST_FILES := settings
 

tools/testing/selftests/net/cmsg_sender.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <errno.h>
+#include <error.h>
+#include <netdb.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <linux/errqueue.h>
+#include <linux/icmp.h>
+#include <linux/icmpv6.h>
+#include <linux/net_tstamp.h>
+#include <linux/types.h>
+#include <linux/udp.h>
+#include <sys/socket.h>
+
+enum {
+	ERN_SUCCESS = 0,
+	/* Well defined errors, callers may depend on these */
+	ERN_SEND = 1,
+	/* Informational, can reorder */
+	ERN_HELP,
+	ERN_SEND_SHORT,
+	ERN_SOCK_CREATE,
+	ERN_RESOLVE,
+	ERN_CMSG_WR,
+	ERN_SOCKOPT,
+	ERN_GETTIME,
+	ERN_RECVERR,
+	ERN_CMSG_RD,
+	ERN_CMSG_RCV,
+};
+
+struct options {
+	bool silent_send;
+	const char *host;
+	const char *service;
+	struct {
+		unsigned int mark;
+	} sockopt;
+	struct {
+		unsigned int family;
+		unsigned int type;
+		unsigned int proto;
+	} sock;
+	struct {
+		bool ena;
+		unsigned int val;
+	} mark;
+	struct {
+		bool ena;
+		unsigned int delay;
+	} txtime;
+	struct {
+		bool ena;
+	} ts;
+} opt = {
+	.sock = {
+		.family	= AF_UNSPEC,
+		.type	= SOCK_DGRAM,
+		.proto	= IPPROTO_UDP,
+	},
+};
+
+static struct timespec time_start_real;
+static struct timespec time_start_mono;
+
+static void __attribute__((noreturn)) cs_usage(const char *bin)
+{
+	printf("Usage: %s [opts] <dst host> <dst port / service>\n", bin);
+	printf("Options:\n"
+	       "\t\t-s      Silent send() failures\n"
+	       "\t\t-4/-6   Force IPv4 / IPv6 only\n"
+	       "\t\t-p prot Socket protocol\n"
+	       "\t\t        (u = UDP (default); i = ICMP; r = RAW)\n"
+	       "\n"
+	       "\t\t-m val  Set SO_MARK with given value\n"
+	       "\t\t-M val  Set SO_MARK via setsockopt\n"
+	       "\t\t-d val  Set SO_TXTIME with given delay (usec)\n"
+	       "\t\t-t      Enable time stamp reporting\n"
+	       "");
+	exit(ERN_HELP);
+}
+
+static void cs_parse_args(int argc, char *argv[])
+{
+	char o;
+
+	while ((o = getopt(argc, argv, "46sp:m:M:d:t")) != -1) {
+		switch (o) {
+		case 's':
+			opt.silent_send = true;
+			break;
+		case '4':
+			opt.sock.family = AF_INET;
+			break;
+		case '6':
+			opt.sock.family = AF_INET6;
+			break;
+		case 'p':
+			if (*optarg == 'u' || *optarg == 'U') {
+				opt.sock.proto = IPPROTO_UDP;
+			} else if (*optarg == 'i' || *optarg == 'I') {
+				opt.sock.proto = IPPROTO_ICMP;
+			} else if (*optarg == 'r') {
+				opt.sock.type = SOCK_RAW;
+			} else {
+				printf("Error: unknown protocol: %s\n", optarg);
+				cs_usage(argv[0]);
+			}
+			break;
+
+		case 'm':
+			opt.mark.ena = true;
+			opt.mark.val = atoi(optarg);
+			break;
+		case 'M':
+			opt.sockopt.mark = atoi(optarg);
+			break;
+		case 'd':
+			opt.txtime.ena = true;
+			opt.txtime.delay = atoi(optarg);
+			break;
+		case 't':
+			opt.ts.ena = true;
+			break;
+		}
+	}
+
+	if (optind != argc - 2)
+		cs_usage(argv[0]);
+
+	opt.host = argv[optind];
+	opt.service = argv[optind + 1];
+}
+
+static void
+cs_write_cmsg(int fd, struct msghdr *msg, char *cbuf, size_t cbuf_sz)
+{
+	struct cmsghdr *cmsg;
+	size_t cmsg_len;
+
+	msg->msg_control = cbuf;
+	cmsg_len = 0;
+
+	if (opt.mark.ena) {
+		cmsg = (struct cmsghdr *)(cbuf + cmsg_len);
+		cmsg_len += CMSG_SPACE(sizeof(__u32));
+		if (cbuf_sz < cmsg_len)
+			error(ERN_CMSG_WR, EFAULT, "cmsg buffer too small");
+
+		cmsg->cmsg_level = SOL_SOCKET;
+		cmsg->cmsg_type = SO_MARK;
+		cmsg->cmsg_len = CMSG_LEN(sizeof(__u32));
+		*(__u32 *)CMSG_DATA(cmsg) = opt.mark.val;
+	}
+	if (opt.txtime.ena) {
+		struct sock_txtime so_txtime = {
+			.clockid = CLOCK_MONOTONIC,
+		};
+		__u64 txtime;
+
+		if (setsockopt(fd, SOL_SOCKET, SO_TXTIME,
+			       &so_txtime, sizeof(so_txtime)))
+			error(ERN_SOCKOPT, errno, "setsockopt TXTIME");
+
+		txtime = time_start_mono.tv_sec * (1000ULL * 1000 * 1000) +
+			 time_start_mono.tv_nsec +
+			 opt.txtime.delay * 1000;
+
+		cmsg = (struct cmsghdr *)(cbuf + cmsg_len);
+		cmsg_len += CMSG_SPACE(sizeof(txtime));
+		if (cbuf_sz < cmsg_len)
+			error(ERN_CMSG_WR, EFAULT, "cmsg buffer too small");
+
+		cmsg->cmsg_level = SOL_SOCKET;
+		cmsg->cmsg_type = SCM_TXTIME;
+		cmsg->cmsg_len = CMSG_LEN(sizeof(txtime));
+		memcpy(CMSG_DATA(cmsg), &txtime, sizeof(txtime));
+	}
+	if (opt.ts.ena) {
+		__u32 val = SOF_TIMESTAMPING_SOFTWARE |
+			    SOF_TIMESTAMPING_OPT_TSONLY;
+
+		if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPING,
+			       &val, sizeof(val)))
+			error(ERN_SOCKOPT, errno, "setsockopt TIMESTAMPING");
+
+		cmsg = (struct cmsghdr *)(cbuf + cmsg_len);
+		cmsg_len += CMSG_SPACE(sizeof(__u32));
+		if (cbuf_sz < cmsg_len)
+			error(ERN_CMSG_WR, EFAULT, "cmsg buffer too small");
+
+		cmsg->cmsg_level = SOL_SOCKET;
+		cmsg->cmsg_type = SO_TIMESTAMPING;
+		cmsg->cmsg_len = CMSG_LEN(sizeof(__u32));
+		*(__u32 *)CMSG_DATA(cmsg) = SOF_TIMESTAMPING_TX_SCHED |
+					    SOF_TIMESTAMPING_TX_SOFTWARE;
+	}
+
+	if (cmsg_len)
+		msg->msg_controllen = cmsg_len;
+	else
+		msg->msg_control = NULL;
+}
+
+static const char *cs_ts_info2str(unsigned int info)
+{
+	static const char *names[] = {
+		[SCM_TSTAMP_SND]	= "SND",
+		[SCM_TSTAMP_SCHED]	= "SCHED",
+		[SCM_TSTAMP_ACK]	= "ACK",
+	};
+
+	if (info < sizeof(names) / sizeof(names[0]))
+		return names[info];
+	return "unknown";
+}
+
+static void
+cs_read_cmsg(int fd, struct msghdr *msg, char *cbuf, size_t cbuf_sz)
+{
+	struct sock_extended_err *see;
+	struct scm_timestamping *ts;
+	struct cmsghdr *cmsg;
+	int i, err;
+
+	if (!opt.ts.ena)
+		return;
+	msg->msg_control = cbuf;
+	msg->msg_controllen = cbuf_sz;
+
+	while (true) {
+		ts = NULL;
+		see = NULL;
+		memset(cbuf, 0, cbuf_sz);
+
+		err = recvmsg(fd, msg, MSG_ERRQUEUE);
+		if (err < 0) {
+			if (errno == EAGAIN)
+				break;
+			error(ERN_RECVERR, errno, "recvmsg ERRQ");
+		}
+
+		for (cmsg = CMSG_FIRSTHDR(msg); cmsg != NULL;
+		     cmsg = CMSG_NXTHDR(msg, cmsg)) {
+			if (cmsg->cmsg_level == SOL_SOCKET &&
+			    cmsg->cmsg_type == SO_TIMESTAMPING_OLD) {
+				if (cmsg->cmsg_len < sizeof(*ts))
+					error(ERN_CMSG_RD, EINVAL, "TS cmsg");
+
+				ts = (void *)CMSG_DATA(cmsg);
+			}
+			if ((cmsg->cmsg_level == SOL_IP &&
+			     cmsg->cmsg_type == IP_RECVERR) ||
+			    (cmsg->cmsg_level == SOL_IPV6 &&
+			     cmsg->cmsg_type == IPV6_RECVERR)) {
+				if (cmsg->cmsg_len < sizeof(*see))
+					error(ERN_CMSG_RD, EINVAL, "sock_err cmsg");
+
+				see = (void *)CMSG_DATA(cmsg);
+			}
+		}
+
+		if (!ts)
+			error(ERN_CMSG_RCV, ENOENT, "TS cmsg not found");
+		if (!see)
+			error(ERN_CMSG_RCV, ENOENT, "sock_err cmsg not found");
+
+		for (i = 0; i < 3; i++) {
+			unsigned long long rel_time;
+
+			if (!ts->ts[i].tv_sec && !ts->ts[i].tv_nsec)
+				continue;
+
+			rel_time = (ts->ts[i].tv_sec - time_start_real.tv_sec) *
+				(1000ULL * 1000) +
+				(ts->ts[i].tv_nsec - time_start_real.tv_nsec) /
+				1000;
+			printf(" %5s ts%d %lluus\n",
+			       cs_ts_info2str(see->ee_info),
+			       i, rel_time);
+		}
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	char buf[] = "blablablabla";
+	struct addrinfo hints, *ai;
+	struct iovec iov[1];
+	struct msghdr msg;
+	char cbuf[1024];
+	int err;
+	int fd;
+
+	cs_parse_args(argc, argv);
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = opt.sock.family;
+
+	ai = NULL;
+	err = getaddrinfo(opt.host, opt.service, &hints, &ai);
+	if (err) {
+		fprintf(stderr, "Can't resolve address [%s]:%s\n",
+			opt.host, opt.service);
+		return ERN_SOCK_CREATE;
+	}
+
+	if (ai->ai_family == AF_INET6 && opt.sock.proto == IPPROTO_ICMP)
+		opt.sock.proto = IPPROTO_ICMPV6;
+
+	fd = socket(ai->ai_family, opt.sock.type, opt.sock.proto);
+	if (fd < 0) {
+		fprintf(stderr, "Can't open socket: %s\n", strerror(errno));
+		freeaddrinfo(ai);
+		return ERN_RESOLVE;
+	}
+
+	if (opt.sock.proto == IPPROTO_ICMP) {
+		buf[0] = ICMP_ECHO;
+		buf[1] = 0;
+	} else if (opt.sock.proto == IPPROTO_ICMPV6) {
+		buf[0] = ICMPV6_ECHO_REQUEST;
+		buf[1] = 0;
+	} else if (opt.sock.type == SOCK_RAW) {
+		struct udphdr hdr = { 1, 2, htons(sizeof(buf)), 0 };
+		struct sockaddr_in6 *sin6 = (void *)ai->ai_addr;;
+
+		memcpy(buf, &hdr, sizeof(hdr));
+		sin6->sin6_port = htons(opt.sock.proto);
+	}
+
+	if (opt.sockopt.mark &&
+	    setsockopt(fd, SOL_SOCKET, SO_MARK,
+		       &opt.sockopt.mark, sizeof(opt.sockopt.mark)))
+		error(ERN_SOCKOPT, errno, "setsockopt SO_MARK");
+
+	if (clock_gettime(CLOCK_REALTIME, &time_start_real))
+		error(ERN_GETTIME, errno, "gettime REALTIME");
+	if (clock_gettime(CLOCK_MONOTONIC, &time_start_mono))
+		error(ERN_GETTIME, errno, "gettime MONOTINIC");
+
+	iov[0].iov_base = buf;
+	iov[0].iov_len = sizeof(buf);
+
+	memset(&msg, 0, sizeof(msg));
+	msg.msg_name = ai->ai_addr;
+	msg.msg_namelen = ai->ai_addrlen;
+	msg.msg_iov = iov;
+	msg.msg_iovlen = 1;
+
+	cs_write_cmsg(fd, &msg, cbuf, sizeof(cbuf));
+
+	err = sendmsg(fd, &msg, 0);
+	if (err < 0) {
+		if (!opt.silent_send)
+			fprintf(stderr, "send failed: %s\n", strerror(errno));
+		err = ERN_SEND;
+		goto err_out;
+	} else if (err != sizeof(buf)) {
+		fprintf(stderr, "short send\n");
+		err = ERN_SEND_SHORT;
+		goto err_out;
+	} else {
+		err = ERN_SUCCESS;
+	}
+
+	/* Make sure all timestamps have time to loop back */
+	usleep(opt.txtime.delay);
+
+	cs_read_cmsg(fd, &msg, cbuf, sizeof(cbuf));
+
+err_out:
+	close(fd);
+	freeaddrinfo(ai);
+	return err;
+}

tools/testing/selftests/net/cmsg_so_mark.c

-// SPDX-License-Identifier: GPL-2.0-or-later
-#include <errno.h>
-#include <netdb.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <linux/types.h>
-#include <sys/socket.h>
-
-int main(int argc, const char **argv)
-{
-	char cbuf[CMSG_SPACE(sizeof(__u32))];
-	struct addrinfo hints, *ai;
-	struct cmsghdr *cmsg;
-	struct iovec iov[1];
-	struct msghdr msg;
-	int mark;
-	int err;
-	int fd;
-
-	if (argc != 4) {
-		fprintf(stderr, "Usage: %s <dst_ip> <port> <mark>\n", argv[0]);
-		return 1;
-	}
-	mark = atoi(argv[3]);
-
-	memset(&hints, 0, sizeof(hints));
-	hints.ai_family = AF_UNSPEC;
-	hints.ai_socktype = SOCK_DGRAM;
-
-	ai = NULL;
-	err = getaddrinfo(argv[1], argv[2], &hints, &ai);
-	if (err) {
-		fprintf(stderr, "Can't resolve address: %s\n", strerror(errno));
-		return 1;
-	}
-
-	fd = socket(ai->ai_family, SOCK_DGRAM, IPPROTO_UDP);
-	if (fd < 0) {
-		fprintf(stderr, "Can't open socket: %s\n", strerror(errno));
-		freeaddrinfo(ai);
-		return 1;
-	}
-
-	iov[0].iov_base = "bla";
-	iov[0].iov_len = 4;
-
-	msg.msg_name = ai->ai_addr;
-	msg.msg_namelen = ai->ai_addrlen;
-	msg.msg_iov = iov;
-	msg.msg_iovlen = 1;
-	msg.msg_control = cbuf;
-	msg.msg_controllen = sizeof(cbuf);
-
-	cmsg = CMSG_FIRSTHDR(&msg);
-	cmsg->cmsg_level = SOL_SOCKET;
-	cmsg->cmsg_type = SO_MARK;
-	cmsg->cmsg_len = CMSG_LEN(sizeof(__u32));
-	*(__u32 *)CMSG_DATA(cmsg) = mark;
-
-	err = sendmsg(fd, &msg, 0);
-
-	close(fd);
-	freeaddrinfo(ai);
-	return err != 4;
-}

tools/testing/selftests/net/cmsg_so_mark.sh

@@ -18,6 +18,8 @@ trap cleanup EXIT
 # Namespaces
 ip netns add $NS
 
+ip netns exec $NS sysctl -w net.ipv4.ping_group_range='0 2147483647' > /dev/null
+
 # Connectivity
 ip -netns $NS link add type dummy
 ip -netns $NS link set dev dummy0 up
@@ -41,15 +43,29 @@ check_result() {
     fi
 }
 
-ip netns exec $NS ./cmsg_so_mark $TGT4 1234 $((MARK + 1))
-check_result $? 0 "IPv4 pass"
-ip netns exec $NS ./cmsg_so_mark $TGT6 1234 $((MARK + 1))
-check_result $? 0 "IPv6 pass"
+for ovr in setsock cmsg both; do
+    for i in 4 6; do
+	[ $i == 4 ] && TGT=$TGT4 || TGT=$TGT6
+
+	for p in u i r; do
+	    [ $p == "u" ] && prot=UDP
+	    [ $p == "i" ] && prot=ICMP
+	    [ $p == "r" ] && prot=RAW
+
+	    [ $ovr == "setsock" ] && m="-M"
+	    [ $ovr == "cmsg" ]    && m="-m"
+	    [ $ovr == "both" ]    && m="-M $MARK -m"
+
+	    ip netns exec $NS ./cmsg_sender -$i -p $p $m $((MARK + 1)) $TGT 1234
+	    check_result $? 0 "$prot $ovr - pass"
+
+	    [ $ovr == "diff" ] && m="-M $((MARK + 1)) -m"
 
-ip netns exec $NS ./cmsg_so_mark $TGT4 1234 $MARK
-check_result $? 1 "IPv4 rejection"
-ip netns exec $NS ./cmsg_so_mark $TGT6 1234 $MARK
-check_result $? 1 "IPv6 rejection"
+	    ip netns exec $NS ./cmsg_sender -$i -p $p $m $MARK -s $TGT 1234
+	    check_result $? 1 "$prot $ovr - rejection"
+	done
+    done
+done
 
 # Summary
 if [ $BAD -ne 0 ]; then

tools/testing/selftests/net/cmsg_time.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+NS=ns
+IP4=172.16.0.1/24
+TGT4=172.16.0.2
+IP6=2001:db8:1::1/64
+TGT6=2001:db8:1::2
+
+cleanup()
+{
+    ip netns del $NS
+}
+
+trap cleanup EXIT
+
+# Namespaces
+ip netns add $NS
+
+ip netns exec $NS sysctl -w net.ipv4.ping_group_range='0 2147483647' > /dev/null
+
+# Connectivity
+ip -netns $NS link add type dummy
+ip -netns $NS link set dev dummy0 up
+ip -netns $NS addr add $IP4 dev dummy0
+ip -netns $NS addr add $IP6 dev dummy0
+
+# Need FQ for TXTIME
+ip netns exec $NS tc qdisc replace dev dummy0 root fq
+
+# Test
+BAD=0
+TOTAL=0
+
+check_result() {
+    ((TOTAL++))
+    if [ $1 -ne 0 ]; then
+	echo "  Case $4 returned $1, expected 0"
+	((BAD++))
+    elif [ "$2" != "$3" ]; then
+	echo "  Case $4 returned '$2', expected '$3'"
+	((BAD++))
+    fi
+}
+
+for i in "-4 $TGT4" "-6 $TGT6"; do
+    for p in u i r; do
+	[ $p == "u" ] && prot=UDPv${i:1:2}
+	[ $p == "i" ] && prot=ICMPv${i:1:2}
+	[ $p == "r" ] && prot=RAWv${i:1:2}
+
+	ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234)
+	check_result $? "$ts" "" "$prot - no options"
+
+	ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234 -t | wc -l)
+	check_result $? "$ts" "2" "$prot - ts cnt"
+	ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234 -t |
+		 sed -n "s/.*SCHED ts0 [0-9].*/OK/p")
+	check_result $? "$ts" "OK" "$prot - ts0 SCHED"
+	ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234 -t |
+		 sed -n "s/.*SND ts0 [0-9].*/OK/p")
+	check_result $? "$ts" "OK" "$prot - ts0 SND"
+
+	ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234 -t -d 1000 |
+		 awk '/SND/ { if ($3 > 1000) print "OK"; }')
+	check_result $? "$ts" "OK" "$prot - TXTIME abs"
+
+	ts=$(ip netns exec $NS ./cmsg_sender -p $p $i 1234 -t -d 1000 |
+		 awk '/SND/ {snd=$3}
+		      /SCHED/ {sch=$3}
+		      END { if (snd - sch > 500) print "OK"; }')
+	check_result $? "$ts" "OK" "$prot - TXTIME rel"
+    done
+done
+
+# Summary
+if [ $BAD -ne 0 ]; then
+    echo "FAIL - $BAD/$TOTAL cases failed"
+    exit 1
+else
+    echo "OK"
+    exit 0
+fi