Add -z "TOS" option to ping6, to test DSCP/ECN values

ping has the option to add the (deprecated) TOS byte
using the -z option. Adding the same option, with the
same (deprecated) Traffic Class Byte (nowadays actually
DSCP and ECN fields) to ping6 to validate proper QoS
processing in network switches.

Reviewed by:	tuexen
MFC after:	2 weeks
Sponsored by:	NetApp, Inc.
Differential Revision:	https://reviews.freebsd.org/D26384

2 files changed, 22 insertions, 2 deletions

diff --git a/sbin/ping6/ping6.8 b/sbin/ping6/ping6.8
index 19cc24b6965b..bc4c670ac361 100644
--- a/sbin/ping6/ping6.8
+++ b/sbin/ping6/ping6.8
@@ -29,7 +29,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd October 20, 2019
+.Dd September 10, 2020
 .Dt PING6 8
 .Os
 .Sh NAME
@@ -87,6 +87,9 @@ packets to network hosts
 .Op Fl W Ar waittime
 .Ek
 .Bk -words
+.Op Fl z Ar tclass
+.Ek
+.Bk -words
 .Op Ar hops ...
 .Ek
 .Bk -words
@@ -329,6 +332,8 @@ This option is present for backward compatibility.
 has no effect if
 .Fl y
 is specified.
+.It Fl z Ar tclass
+Use the specified traffic class when sending.
 .It Ar hops
 IPv6 addresses for intermediate nodes,
 which will be put into type 0 routing header.
diff --git a/sbin/ping6/ping6.c b/sbin/ping6/ping6.c
index 998f4a51ff3a..756d4d6b50e1 100644
--- a/sbin/ping6/ping6.c
+++ b/sbin/ping6/ping6.c
@@ -229,6 +229,7 @@ static char *hostname;
 static int ident;		/* process id to identify our packets */
 static u_int8_t nonce[8];	/* nonce field for node information */
 static int hoplimit = -1;	/* hoplimit */
+static int tclass = -1;		/* traffic class */
 static u_char *packet = NULL;
 static cap_channel_t *capdns;
 
@@ -352,7 +353,7 @@ main(int argc, char *argv[])
 #endif /*IPSEC_POLICY_IPSEC*/
 #endif
 	while ((ch = getopt(argc, argv,
-	    "k:b:c:DdfHe:m:I:i:l:unNop:qaAS:s:OvyYW:t:" ADDOPTS)) != -1) {
+	    "k:b:c:DdfHe:m:I:i:l:unNop:qaAS:s:OvyYW:t:z:" ADDOPTS)) != -1) {
 #undef ADDOPTS
 		switch (ch) {
 		case 'k':
@@ -585,6 +586,14 @@ main(int argc, char *argv[])
 					err(1, "setitimer");
 			}
 			break;
+		case 'z':		/* traffic class */
+			tclass = strtol(optarg, &e, 10);
+			if (*optarg == '\0' || *e != '\0')
+				errx(1, "illegal traffic class %s", optarg);
+			if (255 < tclass || tclass < -1)
+				errx(1,
+				    "illegal traffic class -- %s", optarg);
+			break;
 #ifdef IPSEC
 #ifdef IPSEC_POLICY_IPSEC
 		case 'P':
@@ -937,6 +946,12 @@ main(int argc, char *argv[])
 		scmsgp = CMSG_NXTHDR(&smsghdr, scmsgp);
 	}
 
+	if (tclass != -1) {
+		if (setsockopt(ssend, IPPROTO_IPV6, IPV6_TCLASS,
+		    &tclass, sizeof(tclass)) == -1)
+			err(1, "setsockopt(IPV6_TCLASS)");
+	}
+
 	if (argc > 1) {	/* some intermediate addrs are specified */
 		int hops;
 		int rthdrlen;