On Wed 18/07/2018 08:54, Florian Obser wrote:
> During g2k18 I commited rad(8).
>
> The latest amd64 and i386 snapshots should contain it with enough
> features to replace rtadvd(8). If you are using rtadvd(8) I'd
> appreciate if you could switch to rad(8) and report back if any
> features are missing.
Florian,
Thank you for rad(8). I like the configuration format, and it seems to
work for me as replacement for rtadvd(8). For reference purposes:
$ cat /etc/rtadvd.conf
vlan1003:\
:mtu#1480:\
:rdnss="2001:470:7ce4:1::1":\
:dnssl="guest":
$ cat /etc/rad.conf
interface vlan1003 {
dns {
resolver 2001:470:7ce4:1::1
search guest
}
}
There is one thing that I'm missing, and that is the MTU option in RA
messages (RFC 4861 Section 4.6.4). I've baked up a diff which works for
me. My current rad.conf looks like:
interface vlan1003 {
dns {
resolver 2001:470:7ce4:1::1
search guest
}
mtu 1480
}
Output "tcpdump -vvvv -ttt -i vlan1003 icmp6 and 'ip6[40] = 134'":
Jul 19 21:26:10.009348 fe80::a562:1f47:a75c:a5fc > ff02::1: icmp6: router
advertisement(chlim=0, pref=medium, router_ltime=1800, reachable_time=0,
retrans_time=0)(prefix info: LA valid_ltime=2592000, preferred_ltime=604800,
prefix=2001:470:7ce4:1::/64)(mtu: mtu=1480)[ndp opt] (len 88, hlim 255)
I'm not sure this is an option for rad(8) that is useful for anyone else
but me. What do you think? Also, what do you think of the diff below?
diff --git engine.c engine.c
index 5d186439dd8..4ade634a689 100644
--- engine.c
+++ engine.c
@@ -355,6 +355,9 @@ engine_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INSERT_TAIL(&ra_iface_conf->ra_prefix_list,
ra_prefix_conf, entry);
break;
+ case IMSG_RECONF_RA_MTU:
+ ra_iface_conf->ra_mtu = *((uint32_t *)imsg.data);
+ break;
case IMSG_RECONF_RA_RDNS_LIFETIME:
ra_iface_conf->rdns_lifetime = *((uint32_t *)imsg.data);
break;
diff --git frontend.c frontend.c
index b06fa43038c..06c4cc5cb2b 100644
--- frontend.c
+++ frontend.c
@@ -397,6 +397,9 @@ frontend_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INSERT_TAIL(&ra_iface_conf->ra_prefix_list,
ra_prefix_conf, entry);
break;
+ case IMSG_RECONF_RA_MTU:
+ ra_iface_conf->ra_mtu = *((uint32_t *)imsg.data);
+ break;
case IMSG_RECONF_RA_RDNS_LIFETIME:
ra_iface_conf->rdns_lifetime = *((uint32_t *)imsg.data);
break;
@@ -888,6 +891,7 @@ build_packet(struct ra_iface *ra_iface)
{
struct nd_router_advert *ra;
struct nd_opt_prefix_info *ndopt_pi;
+ struct nd_opt_mtu *ndopt_mtu;
struct ra_iface_conf *ra_iface_conf;
struct ra_options_conf *ra_options_conf;
struct ra_prefix_conf *ra_prefix_conf;
@@ -960,6 +964,15 @@ build_packet(struct ra_iface *ra_iface)
p += sizeof(*ndopt_pi);
}
+ if (ra_iface_conf->ra_mtu > 0) {
+ ndopt_mtu = (struct nd_opt_mtu *)p;
+ ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU;
+ ndopt_mtu->nd_opt_mtu_len = 1;
+ ndopt_mtu->nd_opt_mtu_reserved = 0;
+ ndopt_mtu->nd_opt_mtu_mtu = htonl(ra_iface_conf->ra_mtu);
+ p += sizeof(*ndopt_mtu);
+ }
+
if (ra_iface_conf->rdnss_count > 0) {
ndopt_rdnss = (struct nd_opt_rdnss *)p;
ndopt_rdnss->nd_opt_rdnss_type = ND_OPT_RDNSS;
diff --git parse.y parse.y
index 582d165c7d6..9696ac58213 100644
--- parse.y
+++ parse.y
@@ -115,7 +115,7 @@ typedef struct {
%token DEFAULT ROUTER HOP LIMIT MANAGED ADDRESS
%token CONFIGURATION OTHER LIFETIME REACHABLE TIME RETRANS TIMER
%token AUTO PREFIX VALID PREFERRED LIFETIME ONLINK AUTONOMOUS
-%token ADDRESS_CONFIGURATION DNS RESOLVER SEARCH
+%token ADDRESS_CONFIGURATION DNS RESOLVER SEARCH MTU
%token <v.string> STRING
%token <v.number> NUMBER
@@ -265,6 +265,9 @@ ra_ifaceoptsl : NO AUTO PREFIX {
} ra_prefix_block {
ra_prefix_conf = NULL;
}
+ | MTU NUMBER {
+ ra_iface_conf->ra_mtu = $2;
+ }
| DNS dns_block
| ra_opt_block
;
@@ -423,6 +426,7 @@ lookup(char *s)
{"lifetime", LIFETIME},
{"limit", LIMIT},
{"managed", MANAGED},
+ {"mtu", MTU},
{"no", NO},
{"on-link", ONLINK},
{"other", OTHER},
@@ -958,6 +962,8 @@ conf_get_ra_iface(char *name)
/* Inherit attributes set in global section. */
iface->ra_options = conf->ra_options;
+ iface->ra_mtu = DEFAULT_MTU;
+
iface->rdns_lifetime = DEFAULT_RDNS_LIFETIME;
SIMPLEQ_INIT(&iface->ra_prefix_list);
diff --git printconf.c printconf.c
index 1fc8cd4ca3f..0285bdb75be 100644
--- printconf.c
+++ printconf.c
@@ -99,6 +99,9 @@ print_config(struct rad_conf *conf)
printf("\t}\n");
}
+ if (iface->ra_mtu > 0)
+ printf("\tmtu %u\n", iface->ra_mtu);
+
if (!SIMPLEQ_EMPTY(&iface->ra_rdnss_list) ||
!SIMPLEQ_EMPTY(&iface->ra_dnssl_list)) {
printf("\tdns {\n");
diff --git rad.c rad.c
index 4652e1e0fb7..cdaf529d806 100644
--- rad.c
+++ rad.c
@@ -622,6 +622,9 @@ main_imsg_send_config(struct rad_conf *xconf)
ra_prefix_conf, sizeof(*ra_prefix_conf)) == -1)
return (-1);
}
+ if (main_sendboth(IMSG_RECONF_RA_MTU, &ra_iface_conf->ra_mtu,
+ sizeof(ra_iface_conf->ra_mtu)) == -1)
+ return (-1);
if (main_sendboth(IMSG_RECONF_RA_RDNS_LIFETIME,
&ra_iface_conf->rdns_lifetime,
sizeof(ra_iface_conf->rdns_lifetime)) == -1)
diff --git rad.conf.5 rad.conf.5
index 6ca6b3ef956..6165e74070d 100644
--- rad.conf.5
+++ rad.conf.5
@@ -126,6 +126,14 @@ prefix.
The default is 2592000.
.El
.Pp
+A maximum transmission unit (MTU) field can be advertised by configuring it
+in an interface block:
+.Bl -tag -width Ds
+.It Ic mtu Ar bytes
+MTU in bytes. If 0 is specified the option will not be included.
+The default is 0.
+.El
+.Pp
Recursive resolvers are configured inside an interface block:
.Bd -unfilled -offset indent
.Ic dns Brq dns options
diff --git rad.h rad.h
index db80d7c772d..8d919303723 100644
--- rad.h
+++ rad.h
@@ -26,6 +26,7 @@
#define OPT_VERBOSE2 0x00000002
#define OPT_NOACTION 0x00000004
+#define DEFAULT_MTU 0
#define MAX_RTR_ADV_INTERVAL 600
#define MIN_RTR_ADV_INTERVAL 200
@@ -59,6 +60,7 @@ enum imsg_type {
IMSG_RECONF_RA_IFACE,
IMSG_RECONF_RA_AUTOPREFIX,
IMSG_RECONF_RA_PREFIX,
+ IMSG_RECONF_RA_MTU,
IMSG_RECONF_RA_RDNS_LIFETIME,
IMSG_RECONF_RA_RDNSS,
IMSG_RECONF_RA_DNSSL,
@@ -114,6 +116,7 @@ struct ra_iface_conf {
struct ra_prefix_conf *autoprefix;
SIMPLEQ_HEAD(ra_prefix_conf_head,
ra_prefix_conf) ra_prefix_list;
+ uint32_t ra_mtu;
uint32_t rdns_lifetime;
SIMPLEQ_HEAD(, ra_rdnss_conf) ra_rdnss_list;
int rdnss_count;
