If no source address is specified and we are running in verbose mode

try to find it with getsockname(2) like ping6(8). Disable printing
for now though because scripts might depend on ping(8)'s output.

1 files changed, 47 insertions, 3 deletions

diff --git a/sbin/ping/ping.c b/sbin/ping/ping.c
index 50bb9ae6b30..1e637c526c5 100644
--- a/sbin/ping/ping.c
+++ b/sbin/ping/ping.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ping.c,v 1.184 2016/09/13 07:17:40 florian Exp $	*/
+/*	$OpenBSD: ping.c,v 1.185 2016/09/17 09:14:30 florian Exp $	*/
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -152,6 +152,8 @@ int moptions;
 #define	MULTICAST_NOLOOP	0x001
 #define	MULTICAST_TTL		0x002
 
+#define DUMMY_PORT	10101
+
 /*
  * MAX_DUP_CHK is the number of bits in received table, i.e. the maximum
  * number of received sequence numbers we can keep track of.  Change 128
@@ -553,6 +555,44 @@ main(int argc, char *argv[])
 		warnx("Could only allocate a receive buffer of %d bytes (default %d)",
 		    bufspace, IP_MAXPACKET);
 
+	if (!source && options & F_VERBOSE) {
+		/*
+		 * get the source address. XXX since we revoked the root
+		 * privilege, we cannot use a raw socket for this.
+		 */
+		int dummy;
+		socklen_t len = sizeof(from4);
+
+		if ((dummy = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
+			err(1, "UDP socket");
+
+		from4.sin_family = AF_INET;
+		from4.sin_addr = dst.sin_addr;
+		from4.sin_port = ntohs(DUMMY_PORT);
+
+		if ((moptions & MULTICAST_NOLOOP) &&
+		    setsockopt(dummy, IPPROTO_IP, IP_MULTICAST_LOOP, &loop,
+		    sizeof(loop)) < 0)
+			err(1, "setsockopt IP_MULTICAST_LOOP");
+		if ((moptions & MULTICAST_TTL) &&
+		    setsockopt(dummy, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
+		    sizeof(ttl)) < 0)
+		err(1, "setsockopt IP_MULTICAST_TTL");
+
+		if (rtableid > 0 &&
+		    setsockopt(dummy, SOL_SOCKET, SO_RTABLE, &rtableid,
+		    sizeof(rtableid)) < 0)
+			err(1, "setsockopt(SO_RTABLE)");
+
+		if (connect(dummy, (struct sockaddr *)&from4, len) < 0)
+			err(1, "UDP connect");
+
+		if (getsockname(dummy, (struct sockaddr *)&from4, &len) < 0)
+			err(1, "getsockname");
+
+		close(dummy);
+	}
+
 	if (options & F_HOSTNAME) {
 		if (pledge("stdio inet dns", NULL) == -1)
 			err(1, "pledge");
@@ -564,8 +604,12 @@ main(int argc, char *argv[])
 	arc4random_buf(&tv64_offset, sizeof(tv64_offset));
 	arc4random_buf(&mac_key, sizeof(mac_key));
 
-	printf("PING %s (%s): %d data bytes\n", hostname,
-	    pr_addr((struct sockaddr *)&dst, sizeof(dst)), datalen);
+	printf("PING %s (", hostname);
+	if (0 && (options & F_VERBOSE))
+		printf("%s --> ", pr_addr((struct sockaddr *)&from4,
+		    sizeof(from4)));
+	printf("%s): %d data bytes\n", pr_addr((struct sockaddr *)&dst,
+	    sizeof(dst)), datalen);
 
 	smsghdr.msg_name = &dst;
 	smsghdr.msg_namelen = sizeof(dst);