ref: e2fcebee26510421db69fc881cc423403839a97d
parent: b8cbbc83d11c1ae9e1fcc4df5e0dd61064411a1c
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Sat Nov 18 11:03:44 EST 2017
6in4: add -m mtu option to specify outer MTU instead of hardcoding the tunnel interface MTU to 1280, we calculate the tunnel MTU from the outside MTU, which can now be specified with the -m mtu option. The deault outside MTU is 1500 - 8 (PPPoE).
--- a/sys/man/8/6in4
+++ b/sys/man/8/6in4
@@ -6,6 +6,9 @@
[
.B -ag
] [
+.B -m
+.I mtu
+] [
.B -x
.I netmtpt
] [
@@ -26,6 +29,9 @@
[
.B -g
] [
+.B -m
+.I mtu
+] [
.B -x
.I netmtpt
] [
@@ -103,6 +109,11 @@
.TP
.B -g
use the tunnel as the default route for global IPv6 addresses
+.TP
+.B -m
+.I mtu
+specifies the outside MTU in bytes from which the inside
+tunnel MTU is derived. Deaults to 1500 - 8 (Ethernet - PPPoE).
.TP
.B -x
use the network mounted at
--- a/sys/src/cmd/ip/6in4.c
+++ b/sys/src/cmd/ip/6in4.c
@@ -46,6 +46,8 @@
#define STFHDR offsetof(Iphdr, payload[0])
+int mtu = 1500-8;
+
int anysender;
int gateway;
int debug;
@@ -71,7 +73,7 @@
static void
usage(void)
{- fprint(2, "usage: %s [-ag] [-x mtpt] [-o mtpt] [-i local4] [local6[/mask]] [remote4 [remote6]]\n",
+ fprint(2, "usage: %s [-ag] [-m mtu] [-x mtpt] [-o mtpt] [-i local4] [local6[/mask]] [remote4 [remote6]]\n",
argv0);
exits("Usage");}
@@ -191,8 +193,8 @@
*v6net = open(path, ORDWR);
if (*v6net < 0 || fprint(cfd, "bind pkt") < 0)
sysfatal("can't bind packet interface: %r");- /* 1280 is MTU, apparently from rfc2460 */
- if (fprint(cfd, "add %I %M %I 1280", local6, localmask, remote6) <= 0)
+ if (fprint(cfd, "add %I %M %I %d", local6, localmask, remote6,
+ mtu - IPV4HDR_LEN) <= 0)
sysfatal("can't set local ipv6 address: %r");close(cfd);
if (debug)
@@ -254,6 +256,9 @@
break;
case 'g':
gateway++;
+ break;
+ case 'm':
+ mtu = atoi(EARGF(usage()));
break;
case 'x':
outside = inside = EARGF(usage());
--- a/sys/src/cmd/ip/ayiya.c
+++ b/sys/src/cmd/ip/ayiya.c
@@ -76,6 +76,8 @@
AYIYA conf;
+int mtu = 1500-8;
+
int gateway;
int debug;
@@ -283,7 +285,7 @@
static void
usage(void)
{- fprint(2, "usage: %s [-g] [-x mtpt] [-k secret] local6[/mask] remote4 remote6\n",
+ fprint(2, "usage: %s [-g] [-m mtu] [-x mtpt] [-k secret] local6[/mask] remote4 remote6\n",
argv0);
exits("Usage");}
@@ -363,8 +365,8 @@
*v6net = open(path, ORDWR);
if (*v6net < 0 || fprint(cfd, "bind pkt") < 0)
sysfatal("can't bind packet interface: %r");- /* 1280 is MTU, apparently from rfc2460 */
- if (fprint(cfd, "add %I %M %I 1280", local6, localmask, remote6) <= 0)
+ if (fprint(cfd, "add %I %M %I %d", local6, localmask, remote6,
+ mtu - (IPV4HDR_LEN+8) - (8+conf.idlen+conf.siglen)) <= 0)
sysfatal("can't set local ipv6 address: %r");close(cfd);
if (debug)
@@ -423,6 +425,9 @@
break;
case 'g':
gateway++;
+ break;
+ case 'm':
+ mtu = atoi(EARGF(usage()));
break;
case 'x':
inside = EARGF(usage());
--
⑨