Module Name: src
Committed By: knakahara
Date: Wed Oct 30 03:45:59 UTC 2019
Modified Files:
src/sys/net: if_gif.c if_gif.h
src/sys/netinet6: in6.h in6_gif.c in6_gif.h
Log Message:
Add sysctl nodes to control fragmentation with IPv[46] over IPv6 gif(4).
New sysctl node "net.inet6.ip6.gifpmtu" means
- 0 (default)
Fragment by IPV6_MMTU. All packets reach the destination certainly,
however the long packet performance is poor.
This is same behavior as before.
- 1
Fragment by outer interface's MTU. The long packet performance would
be good, however the packets may be dropped in some network paths
whose path MTU less than the interface's MTU.
- others
undefined yet
New sysctl node "net.interfaces.gif*.pmtu" means
- -1 (default)
Use system default value (net.inet6.ip6.gifpmtu).
- 0
Fragment by IPV6_MMTU for this gif(4) tunnel.
- 1
Fragment by outer interface's MTU for this gif(4) tunnel.
- others
undefined yet
See RFC4459 for more information and other solutions.
To generate a diff of this commit:
cvs rdiff -u -r1.149 -r1.150 src/sys/net/if_gif.c
cvs rdiff -u -r1.33 -r1.34 src/sys/net/if_gif.h
cvs rdiff -u -r1.96 -r1.97 src/sys/netinet6/in6.h
cvs rdiff -u -r1.94 -r1.95 src/sys/netinet6/in6_gif.c
cvs rdiff -u -r1.17 -r1.18 src/sys/netinet6/in6_gif.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/net/if_gif.c
diff -u src/sys/net/if_gif.c:1.149 src/sys/net/if_gif.c:1.150
--- src/sys/net/if_gif.c:1.149 Thu Sep 19 06:07:24 2019
+++ src/sys/net/if_gif.c Wed Oct 30 03:45:59 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: if_gif.c,v 1.149 2019/09/19 06:07:24 knakahara Exp $ */
+/* $NetBSD: if_gif.c,v 1.150 2019/10/30 03:45:59 knakahara Exp $ */
/* $KAME: if_gif.c,v 1.76 2001/08/20 02:01:02 kjc Exp $ */
/*
@@ -31,7 +31,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_gif.c,v 1.149 2019/09/19 06:07:24 knakahara Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_gif.c,v 1.150 2019/10/30 03:45:59 knakahara Exp $");
#ifdef _KERNEL_OPT
#include "opt_inet.h"
@@ -142,6 +142,58 @@ static int max_gif_nesting = MAX_GIF_NES
static struct sysctllog *gif_sysctl;
+#ifdef INET6
+static int
+sysctl_gif_pmtu_global(SYSCTLFN_ARGS)
+{
+ int error, pmtu;
+ struct sysctlnode node = *rnode;
+
+ pmtu = ip6_gif_pmtu;
+ node.sysctl_data = &pmtu;
+ error = sysctl_lookup(SYSCTLFN_CALL(&node));
+ if (error || newp == NULL)
+ return error;
+
+ switch (pmtu) {
+ case GIF_PMTU_MINMTU:
+ case GIF_PMTU_OUTERMTU:
+ ip6_gif_pmtu = pmtu;
+ break;
+ default:
+ return EINVAL;
+ }
+
+ return 0;
+}
+
+static int
+sysctl_gif_pmtu_perif(SYSCTLFN_ARGS)
+{
+ int error, pmtu;
+ struct sysctlnode node = *rnode;
+ struct gif_softc *sc = (struct gif_softc *)node.sysctl_data;
+
+ pmtu = sc->gif_pmtu;
+ node.sysctl_data = &pmtu;
+ error = sysctl_lookup(SYSCTLFN_CALL(&node));
+ if (error || newp == NULL)
+ return error;
+
+ switch (pmtu) {
+ case GIF_PMTU_SYSDEFAULT:
+ case GIF_PMTU_MINMTU:
+ case GIF_PMTU_OUTERMTU:
+ sc->gif_pmtu = pmtu;
+ break;
+ default:
+ return EINVAL;
+ }
+
+ return 0;
+}
+#endif
+
static void
gif_sysctl_setup(void)
{
@@ -196,6 +248,52 @@ gif_sysctl_setup(void)
NULL, 0, &ip6_gif_hlim, 0,
CTL_NET, PF_INET6, IPPROTO_IPV6,
IPV6CTL_GIF_HLIM, CTL_EOL);
+
+ sysctl_createv(&gif_sysctl, 0, NULL, NULL,
+ CTLFLAG_PERMANENT | CTLFLAG_READWRITE,
+ CTLTYPE_INT, "gifpmtu",
+ SYSCTL_DESCR("Default Path MTU setting for gif tunnels"),
+ sysctl_gif_pmtu_global, 0, NULL, 0,
+ CTL_NET, PF_INET6, IPPROTO_IPV6,
+ IPV6CTL_GIF_PMTU, CTL_EOL);
+#endif
+}
+
+static void
+gif_perif_sysctl_setup(struct sysctllog **clog, struct gif_softc *sc)
+{
+#ifdef INET6
+ const struct sysctlnode *cnode, *rnode;
+ struct ifnet *ifp = &sc->gif_if;
+ const char *ifname = ifp->if_xname;
+ int rv;
+
+ /*
+ * Already created in sysctl_sndq_setup().
+ */
+ sysctl_createv(clog, 0, NULL, &rnode,
+ CTLFLAG_PERMANENT,
+ CTLTYPE_NODE, "interfaces",
+ SYSCTL_DESCR("Per-interface controls"),
+ NULL, 0, NULL, 0,
+ CTL_NET, CTL_CREATE, CTL_EOL);
+ sysctl_createv(clog, 0, &rnode, &rnode,
+ CTLFLAG_PERMANENT,
+ CTLTYPE_NODE, ifname,
+ SYSCTL_DESCR("Interface controls"),
+ NULL, 0, NULL, 0,
+ CTL_CREATE, CTL_EOL);
+
+ rv = sysctl_createv(clog, 0, &rnode, &cnode,
+ CTLFLAG_PERMANENT,
+ CTLTYPE_INT, "pmtu",
+ SYSCTL_DESCR("Path MTU setting for this gif tunnel"),
+ sysctl_gif_pmtu_perif, 0, (void *)sc, 0,
+ CTL_CREATE, CTL_EOL);
+ if (rv != 0)
+ log(LOG_WARNING, "%s: could not attach sysctl node pmtu\n", ifname);
+
+ sc->gif_pmtu = GIF_PMTU_SYSDEFAULT;
#endif
}
@@ -248,6 +346,7 @@ gif_clone_create(struct if_clone *ifc, i
{
struct gif_softc *sc;
struct gif_variant *var;
+ struct ifnet *ifp;
int rv;
sc = kmem_zalloc(sizeof(struct gif_softc), KM_SLEEP);
@@ -260,6 +359,9 @@ gif_clone_create(struct if_clone *ifc, i
return rv;
}
+ ifp = &sc->gif_if;
+ gif_perif_sysctl_setup(&ifp->if_sysctl_log, sc);
+
var = kmem_zalloc(sizeof(*var), KM_SLEEP);
var->gv_softc = sc;
psref_target_init(&var->gv_psref, gv_psref_class);
Index: src/sys/net/if_gif.h
diff -u src/sys/net/if_gif.h:1.33 src/sys/net/if_gif.h:1.34
--- src/sys/net/if_gif.h:1.33 Thu Sep 19 06:07:24 2019
+++ src/sys/net/if_gif.h Wed Oct 30 03:45:59 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: if_gif.h,v 1.33 2019/09/19 06:07:24 knakahara Exp $ */
+/* $NetBSD: if_gif.h,v 1.34 2019/10/30 03:45:59 knakahara Exp $ */
/* $KAME: if_gif.h,v 1.23 2001/07/27 09:21:42 itojun Exp $ */
/*
@@ -76,6 +76,8 @@ struct gif_softc {
kmutex_t gif_lock; /* writer lock for gif_var */
pserialize_t gif_psz;
+ int gif_pmtu;
+
LIST_ENTRY(gif_softc) gif_list; /* list of all gifs */
};
#define GIF_ROUTE_TTL 10
Index: src/sys/netinet6/in6.h
diff -u src/sys/netinet6/in6.h:1.96 src/sys/netinet6/in6.h:1.97
--- src/sys/netinet6/in6.h:1.96 Thu Sep 5 20:17:27 2019
+++ src/sys/netinet6/in6.h Wed Oct 30 03:45:59 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: in6.h,v 1.96 2019/09/05 20:17:27 kamil Exp $ */
+/* $NetBSD: in6.h,v 1.97 2019/10/30 03:45:59 knakahara Exp $ */
/* $KAME: in6.h,v 1.83 2001/03/29 02:55:07 jinmei Exp $ */
/*
@@ -536,6 +536,7 @@ struct ip6_mtuinfo {
/* via router advertisement */
#define IPV6CTL_RTADV_NUMROUTES 44 /* current number of routes */
/* via router advertisement */
+#define IPV6CTL_GIF_PMTU 45 /* gif(4) Path MTU setting */
#endif /* _NETBSD_SOURCE */
#ifdef _KERNEL
Index: src/sys/netinet6/in6_gif.c
diff -u src/sys/netinet6/in6_gif.c:1.94 src/sys/netinet6/in6_gif.c:1.95
--- src/sys/netinet6/in6_gif.c:1.94 Thu Sep 19 06:07:25 2019
+++ src/sys/netinet6/in6_gif.c Wed Oct 30 03:45:59 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: in6_gif.c,v 1.94 2019/09/19 06:07:25 knakahara Exp $ */
+/* $NetBSD: in6_gif.c,v 1.95 2019/10/30 03:45:59 knakahara Exp $ */
/* $KAME: in6_gif.c,v 1.62 2001/07/29 04:27:25 itojun Exp $ */
/*
@@ -31,7 +31,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: in6_gif.c,v 1.94 2019/09/19 06:07:25 knakahara Exp $");
+__KERNEL_RCSID(0, "$NetBSD: in6_gif.c,v 1.95 2019/10/30 03:45:59 knakahara Exp $");
#ifdef _KERNEL_OPT
#include "opt_inet.h"
@@ -73,6 +73,7 @@ static int gif_validate6(const struct ip
struct ifnet *);
int ip6_gif_hlim = GIF_HLIM;
+int ip6_gif_pmtu = 0;
static const struct encapsw in6_gif_encapsw;
@@ -198,12 +199,54 @@ in6_gif_output(struct gif_variant *var,
rtcache_unref(rt, ro_pc);
#ifdef IPV6_MINMTU
+ int flags;
+
/*
- * force fragmentation to minimum MTU, to avoid path MTU discovery.
- * it is too painful to ask for resend of inner packet, to achieve
+ * - GIF_PMTU_MINMTU
+ * Force fragmentation to minimum MTU to avoid path MTU discovery
+ * - GIF_PMTU_OUTERMTU
+ * Trust outer MTU is large enough to send all packets
+ *
+ * It is too painful to ask for resend of inner packet, to achieve
* path MTU discovery for encapsulated packets.
+ *
+ * See RFC4459.
*/
- error = ip6_output(m, 0, ro_pc, IPV6_MINMTU, NULL, NULL, NULL);
+ if (sc->gif_pmtu == GIF_PMTU_SYSDEFAULT) {
+ switch (ip6_gif_pmtu) {
+ case GIF_PMTU_MINMTU:
+ flags = IPV6_MINMTU;
+ break;
+ case GIF_PMTU_OUTERMTU:
+ flags = 0;
+ break;
+ default:
+#ifdef DEBUG
+ log(LOG_DEBUG, "%s: ignore unexpected ip6_gif_pmtu %d\n",
+ __func__, ip6_gif_pmtu);
+#endif
+ flags = IPV6_MINMTU;
+ break;
+ }
+ } else {
+ switch (sc->gif_pmtu) {
+ case GIF_PMTU_MINMTU:
+ flags = IPV6_MINMTU;
+ break;
+ case GIF_PMTU_OUTERMTU:
+ flags = 0;
+ break;
+ default:
+#ifdef DEBUG
+ log(LOG_DEBUG, "%s: ignore unexpected gif_pmtu of %s %d\n",
+ __func__, ifp->if_xname, sc->gif_pmtu);
+#endif
+ flags = IPV6_MINMTU;
+ break;
+ }
+ }
+
+ error = ip6_output(m, 0, ro_pc, flags, NULL, NULL, NULL);
#else
error = ip6_output(m, 0, ro_pc, 0, NULL, NULL, NULL);
#endif
Index: src/sys/netinet6/in6_gif.h
diff -u src/sys/netinet6/in6_gif.h:1.17 src/sys/netinet6/in6_gif.h:1.18
--- src/sys/netinet6/in6_gif.h:1.17 Mon Nov 27 05:02:22 2017
+++ src/sys/netinet6/in6_gif.h Wed Oct 30 03:45:59 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: in6_gif.h,v 1.17 2017/11/27 05:02:22 knakahara Exp $ */
+/* $NetBSD: in6_gif.h,v 1.18 2019/10/30 03:45:59 knakahara Exp $ */
/* $KAME: in6_gif.h,v 1.7 2001/07/26 06:53:16 jinmei Exp $ */
/*
@@ -35,6 +35,11 @@
#define GIF_HLIM 30
extern int ip6_gif_hlim; /* Hop limit for gif encap packet */
+extern int ip6_gif_pmtu; /* Default Path MTU setting for gif tunnels */
+
+#define GIF_PMTU_SYSDEFAULT -1 /* Use system default value (ip6_gif_pmtu) */
+#define GIF_PMTU_MINMTU 0 /* Fragmented by IPV6_MINMTU */
+#define GIF_PMTU_OUTERMTU 1 /* Fragmented by Path MTU of outer path */
struct gif_variant;
struct sockaddr;
