[src/netbsd-1-5]: src/sys/netinet Pullup 1.65 [enami]:

[tv <tv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/fc5a4fcecf11
branches:  netbsd-1-5
changeset: 489754:fc5a4fcecf11
user:      tv <tv%NetBSD.org@localhost>
date:      Tue Oct 17 00:45:36 2000 +0000

description:
Pullup 1.65 [enami]:
- Keep track of allhost multicast address record we joined into
  each in_ifaddr and delete it when an address is purged.
- Don't simply try to delete a multicast address record listed in the
  ia_multiaddrs.  It results a dangling pointer.  Let who holds a
  reference to it to delete it.

Also 1.64 [itojun, req by enami]:
implement multicast kludge table for IPv4.
- when all the interface address is removed from an interface, and there's
  multicast groups still left joined, keep it in kludge table.
- when an interface address is added again, recover multicast groups from
  kludge table.
this will avoid problem with dangling in_ifaddr on pcmcia card removal,
due to the link from multicast group info (in_multi).

diffstat:

 sys/netinet/in.c |  111 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 108 insertions(+), 3 deletions(-)

diffs (159 lines):

diff -r 588e8b165b44 -r fc5a4fcecf11 sys/netinet/in.c
--- a/sys/netinet/in.c  Mon Oct 16 23:56:31 2000 +0000
+++ b/sys/netinet/in.c  Tue Oct 17 00:45:36 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: in.c,v 1.61.4.2 2000/10/06 07:00:37 itojun Exp $       */
+/*     $NetBSD: in.c,v 1.61.4.3 2000/10/17 00:45:36 tv Exp $   */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -145,6 +145,13 @@
 int hostzeroisbroadcast = HOSTZEROBROADCAST;
 
 /*
+ * This list is used to keep track of in_multi chains which belong to
+ * deleted interface addresses.  We use in_ifaddr so that a chain head
+ * won't be deallocated until all multicast address record are deleted.
+ */
+static TAILQ_HEAD(, in_ifaddr) in_mk = TAILQ_HEAD_INITIALIZER(in_mk);
+
+/*
  * Return 1 if an internet address is for a ``local'' host
  * (one to which we have a connection).  If subnetsarelocal
  * is true, this includes other subnets of the local net.
@@ -557,6 +564,15 @@
        TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
        IFAFREE(&ia->ia_ifa);
        TAILQ_REMOVE(&in_ifaddr, ia, ia_list);
+       if (ia->ia_allhosts != NULL)
+               in_delmulti(ia->ia_allhosts);
+       if (LIST_FIRST(&ia->ia_multiaddrs) != NULL &&
+           /*
+            * If the interface is going away, don't bother to save
+            * the multicast entries.
+            */
+           ifp->if_output != if_nulloutput)
+               in_savemkludge(ia);
        IFAFREE(&ia->ia_ifa);
        in_setmaxmtu();
 }
@@ -573,6 +589,7 @@
                        continue;
                in_purgeaddr(ifa, ifp);
        }
+       in_purgemkludge(ifp);
 }
 
 /*
@@ -864,14 +881,19 @@
        if (error == EEXIST)
                error = 0;
        /*
+        * recover multicast kludge entry, if there is.
+        */
+       if (ifp->if_flags & IFF_MULTICAST)
+               in_restoremkludge(ia, ifp);
+       /*
         * If the interface supports multicast, join the "all hosts"
         * multicast group on that interface.
         */
-       if (ifp->if_flags & IFF_MULTICAST) {
+       if ((ifp->if_flags & IFF_MULTICAST) != 0 && ia->ia_allhosts == NULL) {
                struct in_addr addr;
 
                addr.s_addr = INADDR_ALLHOSTS_GROUP;
-               in_addmulti(&addr, ifp);
+               ia->ia_allhosts = in_addmulti(&addr, ifp);
        }
        return (error);
 bad:
@@ -920,6 +942,89 @@
 }
 
 /*
+ * Multicast address kludge:
+ * If there were any multicast addresses attached to this interface address,
+ * either move them to another address on this interface, or save them until
+ * such time as this interface is reconfigured for IPv4.
+ */
+void
+in_savemkludge(oia)
+       struct in_ifaddr *oia;
+{
+       struct in_ifaddr *ia;
+       struct in_multi *inm, *next;
+
+       IFP_TO_IA(oia->ia_ifp, ia);
+       if (ia) {       /* there is another address */
+               for (inm = oia->ia_multiaddrs.lh_first; inm; inm = next){
+                       next = inm->inm_list.le_next;
+                       IFAFREE(&inm->inm_ia->ia_ifa);
+                       IFAREF(&ia->ia_ifa);
+                       inm->inm_ia = ia;
+                       LIST_INSERT_HEAD(&ia->ia_multiaddrs, inm, inm_list);
+               }
+       } else {        /* last address on this if deleted, save */
+               TAILQ_INSERT_TAIL(&in_mk, oia, ia_list);
+               IFAREF(&oia->ia_ifa);
+       }
+}
+
+/*
+ * Continuation of multicast address hack:
+ * If there was a multicast group list previously saved for this interface,
+ * then we re-attach it to the first address configured on the i/f.
+ */
+void
+in_restoremkludge(ia, ifp)
+       struct in_ifaddr *ia;
+       struct ifnet *ifp;
+{
+       struct in_ifaddr *oia;
+
+       for (oia = TAILQ_FIRST(&in_mk); oia != NULL;
+           oia = TAILQ_NEXT(oia, ia_list)) {
+               if (oia->ia_ifp == ifp) {
+                       struct in_multi *inm, *next;
+
+                       for (inm = LIST_FIRST(&oia->ia_multiaddrs);
+                           inm != NULL; inm = next) {
+                               next = LIST_NEXT(inm, inm_list);
+                               IFAFREE(&inm->inm_ia->ia_ifa);
+                               IFAREF(&ia->ia_ifa);
+                               inm->inm_ia = ia;
+                               LIST_INSERT_HEAD(&ia->ia_multiaddrs,
+                                   inm, inm_list);
+                       }
+                       TAILQ_REMOVE(&in_mk, oia, ia_list);
+                       IFAFREE(&oia->ia_ifa);
+                       break;
+               }
+       }
+}
+
+void
+in_purgemkludge(ifp)
+       struct ifnet *ifp;
+{
+       struct in_ifaddr *oia;
+
+       for (oia = TAILQ_FIRST(&in_mk); oia != NULL;
+           oia = TAILQ_NEXT(oia, ia_list)) {
+               if (oia->ia_ifp != ifp)
+                       continue;
+
+               /*
+                * Leaving from all multicast groups joined through
+                * this interface is done via in_pcbpurgeif().
+                */
+
+               TAILQ_REMOVE(&in_mk, oia, ia_list);
+               IFAFREE(&oia->ia_ifa);
+               break;
+       }
+}
+
+/*
  * Add an address to the list of IP multicast addresses for a given interface.
  */
 struct in_multi *