svn commit: r336797 - projects/pnfs-planb-server/usr.sbin/nfsd

[Rick Macklem]

Author: rmacklem
Date: Fri Jul 27 23:34:10 2018
New Revision: 336797
URL: https://svnweb.freebsd.org/changeset/base/336797

Log:
  When parsing the "-p" option for nfsd, only use an IPv6 link local address
  if it is the only address.
  
  Link local addresses that are passed from the MDS to a pNFS client for a DS
  will only work if they are in the same scope zone and the address is
  unambiguous for the client.

Modified:
  projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.8
  projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.c

Modified: projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.8
==============================================================================
--- projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.8	Fri Jul 27 23:28:35 2018	(r336796)
+++ projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.8	Fri Jul 27 23:34:10 2018	(r336797)
@@ -28,7 +28,7 @@
 .\"	@(#)nfsd.8	8.4 (Berkeley) 3/29/95
 .\" $FreeBSD$
 .\"
-.Dd June 30, 2018
+.Dd July 27, 2018
 .Dt NFSD 8
 .Os
 .Sh NAME
@@ -156,6 +156,18 @@ data files for
 and nfsv4-data1 will be used to store data files for
 .Dq /export2 .
 .El
+.sp
+When using IPv6 addresses for DSs
+be wary of using link local addresses.
+The IPv6 address for the DS is sent to the client and there is no scope
+zone in it.
+As such, a link local address may not work for a pNFS client to DS
+TCP connection.
+When parsed,
+.Nm
+will only use a link local address if it is the only address returned by
+.Xr getaddrinfo 3
+for the DS hostname.
 .It Fl m Ar mirror_level
 This option is only meaningful when used with the
 .Fl p

Modified: projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.c
==============================================================================
--- projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.c	Fri Jul 27 23:28:35 2018	(r336796)
+++ projects/pnfs-planb-server/usr.sbin/nfsd/nfsd.c	Fri Jul 27 23:34:10 2018	(r336797)
@@ -1309,7 +1309,17 @@ parse_dsserver(const char *optionarg, struct nfsd_nfsd
 				memcpy(&sin6, res->ai_addr, sizeof(sin6));
 				ad = inet_ntop(AF_INET6, &sin6.sin6_addr, ip6,
 				    sizeof(ip6));
-				break;
+
+				/*
+				 * XXX
+				 * Since a link local address will only
+				 * work if the client and DS are in the
+				 * same scope zone, only use it if it is
+				 * the only address.
+				 */
+				if (ad != NULL &&
+				    !IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr))
+					break;
 			}
 		}
 		if (ad == NULL)