If you attempt to send an ICMP echo to a host on the same ethernet

subnet, and that host is down/turned off, the Tnm::icmp echo command
will fail rather than return an unreachable indication on some
occasions.  This is because the nmicmpd program will occasionally
get an EHOSTDOWN error when doing a sendto() when the ARP entry
resolution times out.

This is a problem since this API can support a list of hosts to
send traffic to, and a single error as described will abort the
entire operation.

(The reviewer claims that he could not duplicate the problem,
but that the patch seems like a good idea anyway.)
PR:		ports/24940
Submitted by:	Louis Mamakos <louie@transsys.com>
Reviewed by:	Stefan Eßer <se@FreeBSD.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/net-mgmt/scotty3/files/patch-unix:nmicmpd.c b/net-mgmt/scotty3/files/patch-unix:nmicmpd.c
new file mode 100644
index 000000000000..6432fa8643d7
--- /dev/null
+++ b/net-mgmt/scotty3/files/patch-unix:nmicmpd.c
@@ -0,0 +1,17 @@
+--- nmicmpd.c.orig      Tue Feb  6 15:34:03 2001
++++ nmicmpd.c   Tue Feb  6 15:44:53 2001
+@@ -924,6 +924,14 @@
+     
+     if (rc != size) {
+	if (rc < 0) {
++ 	  /*
++ 	   *  If we get an EHOSTDOWN error, this probably means that
++ 	   *  the the pending ARP entry has timed out for the host.
++ 	   *  Just ignore the error, and attempt a normal retry.
++ 	   */
++ 	  if (errno == EHOSTDOWN)
++ 	    return 0;
++ 
+	    PosixError("sendto failed");
+        }
+        job->status = ICMP_STATUS_GENERROR;