On 04/11/16(Fri) 10:45, Claudio Jeker wrote:
> On Wed, Nov 02, 2016 at 05:44:14PM +0100, Martin Pieuchot wrote:
> > [..]
> > Diff below should fix that by automagically creating a loopback
> > interface when a new routing domain is created. That mean loX will
> > now correspond to routing domain X.
>
> I like this a lot. I think having a loopback interface per rdomain is kind
> of required but it was something I never finished.
> If we could assign 127.0.0.1 and ::1 to those interfaces automatically
> that would be even better (but that can be done as a second step).
Adding ::1 is trivial, it's a one line change.
To add 127.0.0.1 properly it's another story as currently netstart(8)
sets it.
> > Not that if you are currently using a lo2 and a rdomain 2 this diff
> > will break your rdomain setup.
>
> Should we split loopbacks into lo(4) and e.g. loop(4) one is for loopback
> interfaces from userland and the other is only there for the 127.0.0.1 and
> ::1 loopbacks? At least that we the conflict would be solved since we then
> have different namespaces. Again this is something we can do on top of
> this.
I'm not sure to understand the benefit. What's the use case for loop(4)?
> > I'll write the manual page for rtable_loindex(9) if you're ok with
> > the approach.
>
> I think this approach is fine. The only thing I dislike is how you cram
> ifindex and rdomain id into the rtable 2 rdomain mapping. It feels dirty
> to me to do it that way instead of using a little struct holding the two
> values as independent data.
It is dirty but using a small struct is not possible without revamping the
mp-safeness of rtable_get(9) which is, IMHO, not worth the effort.
Here's an updated diff with man page, I'm asking for oks now that
semarie confirmed the m_pullup(9) regression isn't part of my diff.
Index: sys/kern/init_main.c
===================================================================
RCS file: /cvs/src/sys/kern/init_main.c,v
retrieving revision 1.262
diff -u -p -r1.262 init_main.c
--- sys/kern/init_main.c 7 Nov 2016 00:26:32 -0000 1.262
+++ sys/kern/init_main.c 8 Nov 2016 14:22:12 -0000
@@ -389,6 +389,9 @@ main(void *framep)
msginit();
#endif
+ /* Create default routing table before attaching lo0. */
+ rtable_init();
+
/* Attach pseudo-devices. */
for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
if (pdev->pdev_count > 0)
@@ -398,8 +401,6 @@ main(void *framep)
crypto_init();
swcr_init();
#endif /* CRYPTO */
-
- rtable_init();
/*
* Initialize protocols. Block reception of incoming packets
Index: sys/net/if.c
===================================================================
RCS file: /cvs/src/sys/net/if.c,v
retrieving revision 1.458
diff -u -p -r1.458 if.c
--- sys/net/if.c 8 Nov 2016 10:47:10 -0000 1.458
+++ sys/net/if.c 8 Nov 2016 14:22:12 -0000
@@ -258,7 +258,6 @@ struct srp_gc if_ifp_gc = SRP_GC_INITIAL
struct srp_gc if_map_gc = SRP_GC_INITIALIZER(if_map_dtor, NULL);
struct ifnet_head ifnet = TAILQ_HEAD_INITIALIZER(ifnet);
-unsigned int lo0ifidx;
void
if_idxmap_init(unsigned int limit)
@@ -1350,12 +1349,7 @@ p2p_rtrequest(struct ifnet *ifp, int req
KASSERT(ifa == rt->rt_ifa);
- /*
- * XXX Since lo0 is in the default rdomain we should not
- * (ab)use it for any route related to an interface of a
- * different rdomain.
- */
- lo0ifp = if_get(lo0ifidx);
+ lo0ifp = if_get(rtable_loindex(ifp->if_rdomain));
KASSERT(lo0ifp != NULL);
TAILQ_FOREACH(lo0ifa, &lo0ifp->if_addrlist, ifa_list) {
if (lo0ifa->ifa_addr->sa_family ==
@@ -1438,7 +1432,7 @@ if_up(struct ifnet *ifp)
#ifdef INET6
/* Userland expects the kernel to set ::1 on lo0. */
- if (ifp->if_index == lo0ifidx)
+ if (ifp->if_index == rtable_loindex(0))
in6_ifattach(ifp);
#endif
@@ -1605,14 +1599,31 @@ if_setrdomain(struct ifnet *ifp, int rdo
if (rdomain < 0 || rdomain > RT_TABLEID_MAX)
return (EINVAL);
- /* make sure that the routing table exists */
+ /*
+ * Create the routing table if it does not exist, including its
+ * loopback interface with unit == rdomain.
+ */
if (!rtable_exists(rdomain)) {
+ struct ifnet *loifp;
+ char loifname[IFNAMSIZ];
+
+ snprintf(loifname, sizeof(loifname), "lo%d", rdomain);
+ if ((error = if_clone_create(loifname, 0)))
+ return (error);
+
+ if ((loifp = ifunit(loifname)) == NULL)
+ return (ENXIO);
+
s = splsoftnet();
if ((error = rtable_add(rdomain)) == 0)
- rtable_l2set(rdomain, rdomain);
+ rtable_l2set(rdomain, rdomain, loifp->if_index);
splx(s);
- if (error)
+ if (error) {
+ if_clone_destroy(loifname);
return (error);
+ }
+
+ loifp->if_rdomain = rdomain;
}
/* make sure that the routing table is a real rdomain */
Index: sys/net/if_loop.c
===================================================================
RCS file: /cvs/src/sys/net/if_loop.c,v
retrieving revision 1.76
diff -u -p -r1.76 if_loop.c
--- sys/net/if_loop.c 13 Apr 2016 11:41:15 -0000 1.76
+++ sys/net/if_loop.c 8 Nov 2016 14:22:12 -0000
@@ -121,6 +121,7 @@
#include <net/if_var.h>
#include <net/if_types.h>
#include <net/netisr.h>
+#include <net/rtable.h>
#include <net/route.h>
#include <netinet/in.h>
@@ -182,7 +183,7 @@ loop_clone_create(struct if_clone *ifc,
if (unit == 0) {
if_attachhead(ifp);
if_addgroup(ifp, ifc->ifc_name);
- lo0ifidx = ifp->if_index;
+ rtable_l2set(0, 0, ifp->if_index);
} else
if_attach(ifp);
if_alloc_sadl(ifp);
@@ -195,7 +196,7 @@ loop_clone_create(struct if_clone *ifc,
int
loop_clone_destroy(struct ifnet *ifp)
{
- if (ifp->if_index == lo0ifidx)
+ if (ifp->if_index == rtable_loindex(ifp->if_rdomain))
return (EPERM);
if_detach(ifp);
Index: sys/net/if_var.h
===================================================================
RCS file: /cvs/src/sys/net/if_var.h,v
retrieving revision 1.76
diff -u -p -r1.76 if_var.h
--- sys/net/if_var.h 8 Nov 2016 10:46:05 -0000 1.76
+++ sys/net/if_var.h 8 Nov 2016 14:22:12 -0000
@@ -291,7 +291,6 @@ int niq_enlist(struct niqueue *, struct
sysctl_mq((_n), (_l), (_op), (_olp), (_np), (_nl), &(_niq)->ni_q)
extern struct ifnet_head ifnet;
-extern unsigned int lo0ifidx;
extern struct taskq *softnettq;
void if_start(struct ifnet *);
Index: sys/net/route.c
===================================================================
RCS file: /cvs/src/sys/net/route.c,v
retrieving revision 1.334
diff -u -p -r1.334 route.c
--- sys/net/route.c 8 Nov 2016 10:39:32 -0000 1.334
+++ sys/net/route.c 8 Nov 2016 14:22:12 -0000
@@ -197,8 +197,6 @@ route_init(void)
while (rt_hashjitter == 0)
rt_hashjitter = arc4random();
- if (rtable_add(0) != 0)
- panic("route_init rtable_add");
#ifdef BFD
bfdinit();
#endif
Index: sys/net/rtable.c
===================================================================
RCS file: /cvs/src/sys/net/rtable.c,v
retrieving revision 1.52
diff -u -p -r1.52 rtable.c
--- sys/net/rtable.c 7 Sep 2016 09:36:49 -0000 1.52
+++ sys/net/rtable.c 8 Nov 2016 14:22:12 -0000
@@ -1,7 +1,7 @@
/* $OpenBSD: rtable.c,v 1.52 2016/09/07 09:36:49 mpi Exp $ */
/*
- * Copyright (c) 2014-2015 Martin Pieuchot
+ * Copyright (c) 2014-2016 Martin Pieuchot
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
@@ -41,7 +41,7 @@
* afmap rtmap/dommp
* ----------- --------- -----
* | 0 |--------> | 0 | 0 | ... | 0 | Array mapping rtableid (=index)
- * ----------- --------- ----- to rdomain (=value).
+ * ----------- --------- ----- to rdomain/loopback (=value).
* | AF_INET |.
* ----------- `. .---------. .---------.
* ... `----> | rtable0 | ... | rtableN | Array of pointers for
@@ -59,10 +59,20 @@ struct rtmap {
void **tbl;
};
-/* Array of rtableid -> rdomain mapping. */
+/*
+ * Array of rtableid -> rdomain mapping.
+ *
+ * Only used for the first index as describbed above.
+ */
struct dommp {
unsigned int limit;
- unsigned int *dom;
+ /*
+ * Array to get the routing domain and loopback interface related to
+ * a routing table. Format:
+ *
+ * 8 unused bits | 16 bits for loopback index | 8 bits for rdomain
+ */
+ unsigned int *value;
};
unsigned int rtmap_limit = 0;
@@ -146,6 +156,8 @@ rtable_init(void)
unsigned int keylen = 0;
int i;
+ KASSERT(sizeof(struct rtmap) == sizeof(struct dommp));
+
/* We use index 0 for the rtable/rdomain map. */
af2idx_max = 1;
memset(af2idx, 0, sizeof(af2idx));
@@ -173,6 +185,9 @@ rtable_init(void)
M_WAITOK|M_ZERO);
rtmap_init();
+
+ if (rtable_add(0) != 0)
+ panic("unable to create default routing table");
}
int
@@ -221,7 +236,7 @@ rtable_add(unsigned int id)
/* Use main rtable/rdomain by default. */
dmm = srp_get_locked(&afmap[0]);
- dmm->dom[id] = 0;
+ dmm->value[id] = 0;
return (0);
}
@@ -272,24 +287,42 @@ rtable_l2(unsigned int rtableid)
dmm = srp_enter(&sr, &afmap[0]);
if (rtableid < dmm->limit)
- rdomain = dmm->dom[rtableid];
+ rdomain = (dmm->value[rtableid] & RT_TABLEID_MASK);
srp_leave(&sr);
return (rdomain);
}
+unsigned int
+rtable_loindex(unsigned int rtableid)
+{
+ struct dommp *dmm;
+ unsigned int loifidx = 0;
+ struct srp_ref sr;
+
+ dmm = srp_enter(&sr, &afmap[0]);
+ if (rtableid < dmm->limit)
+ loifidx = (dmm->value[rtableid] >> RT_TABLEID_BITS);
+ srp_leave(&sr);
+
+ return (loifidx);
+}
+
void
-rtable_l2set(unsigned int rtableid, unsigned int rdomain)
+rtable_l2set(unsigned int rtableid, unsigned int rdomain, unsigned int loifidx)
{
struct dommp *dmm;
+ unsigned int value;
KERNEL_ASSERT_LOCKED();
if (!rtable_exists(rtableid) || !rtable_exists(rdomain))
return;
+ value = (rdomain & RT_TABLEID_MASK) + (loifidx << RT_TABLEID_BITS);
+
dmm = srp_get_locked(&afmap[0]);
- dmm->dom[rtableid] = rdomain;
+ dmm->value[rtableid] = value;
}
#ifndef ART
Index: sys/net/rtable.h
===================================================================
RCS file: /cvs/src/sys/net/rtable.h,v
retrieving revision 1.16
diff -u -p -r1.16 rtable.h
--- sys/net/rtable.h 7 Sep 2016 09:36:49 -0000 1.16
+++ sys/net/rtable.h 8 Nov 2016 14:22:12 -0000
@@ -54,7 +54,8 @@ void rtable_init(void);
int rtable_exists(unsigned int);
int rtable_add(unsigned int);
unsigned int rtable_l2(unsigned int);
-void rtable_l2set(unsigned int, unsigned int);
+unsigned int rtable_loindex(unsigned int);
+void rtable_l2set(unsigned int, unsigned int, unsigned int);
struct rtentry *rtable_lookup(unsigned int, struct sockaddr *,
struct sockaddr *, struct sockaddr *, uint8_t);
Index: sys/netinet/ip_output.c
===================================================================
RCS file: /cvs/src/sys/netinet/ip_output.c,v
retrieving revision 1.327
diff -u -p -r1.327 ip_output.c
--- sys/netinet/ip_output.c 4 Sep 2016 17:18:56 -0000 1.327
+++ sys/netinet/ip_output.c 8 Nov 2016 14:22:12 -0000
@@ -211,7 +211,7 @@ reroute:
ia = ifatoia(ro->ro_rt->rt_ifa);
if (ISSET(ro->ro_rt->rt_flags, RTF_LOCAL))
- ifp = if_get(lo0ifidx);
+ ifp = if_get(rtable_loindex(m->m_pkthdr.ph_rtableid));
else
ifp = if_get(ro->ro_rt->rt_ifidx);
if (ifp == NULL) {
Index: sys/netinet6/ip6_input.c
===================================================================
RCS file: /cvs/src/sys/netinet6/ip6_input.c,v
retrieving revision 1.168
diff -u -p -r1.168 ip6_input.c
--- sys/netinet6/ip6_input.c 24 Aug 2016 09:41:12 -0000 1.168
+++ sys/netinet6/ip6_input.c 8 Nov 2016 14:22:12 -0000
@@ -211,7 +211,10 @@ ip6_input(struct mbuf *m)
} else {
if (m->m_next) {
if (m->m_flags & M_LOOP) {
- ip6stat.ip6s_m2m[lo0ifidx]++; /*XXX*/
+ int ifidx;
+
+ ifidx = rtable_loindex(m->m_pkthdr.ph_rtableid);
+ ip6stat.ip6s_m2m[ifidx]++;
} else if (ifp->if_index < nitems(ip6stat.ip6s_m2m))
ip6stat.ip6s_m2m[ifp->if_index]++;
else
Index: sys/netinet6/ip6_output.c
===================================================================
RCS file: /cvs/src/sys/netinet6/ip6_output.c,v
retrieving revision 1.216
diff -u -p -r1.216 ip6_output.c
--- sys/netinet6/ip6_output.c 19 Sep 2016 18:09:09 -0000 1.216
+++ sys/netinet6/ip6_output.c 8 Nov 2016 14:22:12 -0000
@@ -460,7 +460,7 @@ reroute:
goto bad;
}
if (ISSET(rt->rt_flags, RTF_LOCAL))
- ifp = if_get(lo0ifidx);
+ ifp = if_get(rtable_loindex(m->m_pkthdr.ph_rtableid));
else
ifp = if_get(rt->rt_ifidx);
} else {
Index: sys/sys/socket.h
===================================================================
RCS file: /cvs/src/sys/sys/socket.h,v
retrieving revision 1.92
diff -u -p -r1.92 socket.h
--- sys/sys/socket.h 28 Sep 2016 18:50:20 -0000 1.92
+++ sys/sys/socket.h 8 Nov 2016 14:22:12 -0000
@@ -143,7 +143,9 @@ struct splice {
/*
* Maximum number of alternate routing tables
*/
-#define RT_TABLEID_MAX 255
+#define RT_TABLEID_MAX 255
+#define RT_TABLEID_BITS 8
+#define RT_TABLEID_MASK 0xff
#endif /* __BSD_VISIBLE */
Index: share/man/man9/rtable_add.9
===================================================================
RCS file: /cvs/src/share/man/man9/rtable_add.9,v
retrieving revision 1.7
diff -u -p -r1.7 rtable_add.9
--- share/man/man9/rtable_add.9 11 Dec 2015 16:08:30 -0000 1.7
+++ share/man/man9/rtable_add.9 8 Nov 2016 14:28:25 -0000
@@ -21,6 +21,7 @@
.Sh NAME
.Nm rtable_add ,
.Nm rtable_exists ,
+.Nm rtable_loindex ,
.Nm rtable_l2 ,
.Nm rtable_l2set
.Nd routing tables and routing domains interface
@@ -31,6 +32,8 @@
.Ft int
.Fn rtable_exists "unsigned int id"
.Ft unsigned int
+.Fn rtable_loindex "unsigned int id"
+.Ft unsigned int
.Fn rtable_l2 "unsigned int id"
.Ft void
.Fn rtable_l2set "unsigned int id" "unsigned int rdomain"
@@ -53,6 +56,11 @@ if routing table with ID
exists,
.Fa 0
otherwise.
+.It Fn rtable_loindex "unsigned int id"
+Return the default
+.Xr lo 4
+interface index for the routing table with ID of
+.Fa id .
.It Fn rtable_l2 "unsigned int id"
Get the routing domain of routing table with ID of
.Fa id .
@@ -65,6 +73,7 @@ under the routing domain with ID of
.Sh CONTEXT
.Fn rtable_add ,
.Fn rtable_exists ,
+.Fn rtable_loindex ,
.Fn rtable_l2 ,
and
.Fn task_l2set
@@ -82,5 +91,6 @@ already exists.
Memory could not be allocated to extend the list of routing domains.
.El
.Sh SEE ALSO
+.Xr lo 4 ,
.Xr route 4 ,
.Xr route 8
