]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/netinet/in.c
xnu-1699.22.73.tar.gz
[apple/xnu.git] / bsd / netinet / in.c
index 32b8c64f6bf5396dd16979782e1d28f3d3ebc0a9..85b9d38afa59c376a06a641ae9fe1cd709795682 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
+ * Copyright (c) 2000-2011 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -72,6 +72,7 @@
 #include <sys/sysctl.h>
 #include <sys/kern_event.h>
 #include <sys/syslog.h>
+#include <sys/mcache.h>
 #include <kern/zalloc.h>
 
 #include <pexpert/pexpert.h>
@@ -122,42 +123,66 @@ static void in_iahash_remove(struct in_ifaddr *);
 static void in_iahash_insert(struct in_ifaddr *);
 static void in_iahash_insert_ptp(struct in_ifaddr *);
 static struct in_ifaddr *in_ifaddr_alloc(int);
+static void in_ifaddr_attached(struct ifaddr *);
+static void in_ifaddr_detached(struct ifaddr *);
 static void in_ifaddr_free(struct ifaddr *);
 static void in_ifaddr_trace(struct ifaddr *, int);
 
 static int subnetsarelocal = 0;
-SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW
+SYSCTL_INT(_net_inet_ip, OID_AUTO, subnets_are_local, CTLFLAG_RW | CTLFLAG_LOCKED,
        &subnetsarelocal, 0, "");
 
-struct in_multihead in_multihead; /* XXX BSS initialization */
-
 /* Track whether or not the SIOCARPIPLL ioctl has been called */
 __private_extern__     u_int32_t       ipv4_ll_arp_aware = 0;
 
+#define        INIFA_TRACE_HIST_SIZE   32      /* size of trace history */
+
+/* For gdb */
+__private_extern__ unsigned int inifa_trace_hist_size = INIFA_TRACE_HIST_SIZE;
+
 struct in_ifaddr_dbg {
        struct in_ifaddr        inifa;                  /* in_ifaddr */
        struct in_ifaddr        inifa_old;              /* saved in_ifaddr */
-       u_int16_t               inifa_refhold_cnt;      /* # of ifaref */
-       u_int16_t               inifa_refrele_cnt;      /* # of ifafree */
+       u_int16_t               inifa_refhold_cnt;      /* # of IFA_ADDREF */
+       u_int16_t               inifa_refrele_cnt;      /* # of IFA_REMREF */
        /*
         * Alloc and free callers.
         */
        ctrace_t                inifa_alloc;
        ctrace_t                inifa_free;
        /*
-        * Circular lists of ifaref and ifafree callers.
+        * Circular lists of IFA_ADDREF and IFA_REMREF callers.
         */
-       ctrace_t                inifa_refhold[CTRACE_HIST_SIZE];
-       ctrace_t                inifa_refrele[CTRACE_HIST_SIZE];
+       ctrace_t                inifa_refhold[INIFA_TRACE_HIST_SIZE];
+       ctrace_t                inifa_refrele[INIFA_TRACE_HIST_SIZE];
+       /*
+        * Trash list linkage
+        */
+       TAILQ_ENTRY(in_ifaddr_dbg) inifa_trash_link;
 };
 
-static unsigned int inifa_debug;               /* debug flags */
+/* List of trash in_ifaddr entries protected by inifa_trash_lock */
+static TAILQ_HEAD(, in_ifaddr_dbg) inifa_trash_head;
+static decl_lck_mtx_data(, inifa_trash_lock);
+
+#if DEBUG
+static unsigned int inifa_debug = 1;           /* debugging (enabled) */
+#else
+static unsigned int inifa_debug;               /* debugging (disabled) */
+#endif /* !DEBUG */
 static unsigned int inifa_size;                        /* size of zone element */
 static struct zone *inifa_zone;                        /* zone for in_ifaddr */
 
 #define        INIFA_ZONE_MAX          64              /* maximum elements in zone */
 #define        INIFA_ZONE_NAME         "in_ifaddr"     /* zone name */
 
+/*
+ * Return 1 if the address is
+ * - loopback
+ * - unicast or multicast link local
+ * - routed via a link level gateway
+ * - belongs to a directly connected (sub)net
+ */
 int
 inaddr_local(struct in_addr in)
 {
@@ -165,20 +190,27 @@ inaddr_local(struct in_addr in)
        struct sockaddr_in sin;
        int local = 0;
 
-       sin.sin_family = AF_INET;
-       sin.sin_len = sizeof (sin);
-       sin.sin_addr = in;
-       rt = rtalloc1((struct sockaddr *)&sin, 0, 0);
-
-       if (rt != NULL) {
-               RT_LOCK_SPIN(rt);
-               if (rt->rt_gateway->sa_family == AF_LINK ||
-                   (rt->rt_ifp->if_flags & IFF_LOOPBACK))
+       if (ntohl(in.s_addr) == INADDR_LOOPBACK || IN_LINKLOCAL(ntohl(in.s_addr))) {
+               local = 1;
+       } else if (ntohl(in.s_addr) >= INADDR_UNSPEC_GROUP &&
+               ntohl(in.s_addr) <= INADDR_MAX_LOCAL_GROUP) {
                        local = 1;
-               RT_UNLOCK(rt);
-               rtfree(rt);
        } else {
-               local = in_localaddr(in);
+               sin.sin_family = AF_INET;
+               sin.sin_len = sizeof (sin);
+               sin.sin_addr = in;
+               rt = rtalloc1((struct sockaddr *)&sin, 0, 0);
+
+               if (rt != NULL) {
+                       RT_LOCK_SPIN(rt);
+                       if (rt->rt_gateway->sa_family == AF_LINK ||
+                           (rt->rt_ifp->if_flags & IFF_LOOPBACK))
+                               local = 1;
+                       RT_UNLOCK(rt);
+                       rtfree(rt);
+               } else {
+                       local = in_localaddr(in);
+               }
        }
        return (local);
 }
@@ -198,20 +230,28 @@ in_localaddr(struct in_addr in)
        if (subnetsarelocal) {
                lck_rw_lock_shared(in_ifaddr_rwlock);
                for (ia = in_ifaddrhead.tqh_first; ia; 
-                    ia = ia->ia_link.tqe_next)
+                    ia = ia->ia_link.tqe_next) {
+                       IFA_LOCK(&ia->ia_ifa);
                        if ((i & ia->ia_netmask) == ia->ia_net) {
+                               IFA_UNLOCK(&ia->ia_ifa);
                                lck_rw_done(in_ifaddr_rwlock);
                                return (1);
                        }
+                       IFA_UNLOCK(&ia->ia_ifa);
+               }
                lck_rw_done(in_ifaddr_rwlock);
        } else {
                lck_rw_lock_shared(in_ifaddr_rwlock);
                for (ia = in_ifaddrhead.tqh_first; ia;
-                    ia = ia->ia_link.tqe_next)
+                    ia = ia->ia_link.tqe_next) {
+                       IFA_LOCK(&ia->ia_ifa);
                        if ((i & ia->ia_subnetmask) == ia->ia_subnet) {
+                               IFA_UNLOCK(&ia->ia_ifa);
                                lck_rw_done(in_ifaddr_rwlock);
                                return (1);
                        }
+                       IFA_UNLOCK(&ia->ia_ifa);
+               }
                lck_rw_done(in_ifaddr_rwlock);
        }
        return (0);
@@ -292,6 +332,18 @@ in_len2mask(struct in_addr *mask, int len)
 
 static int in_interfaces;      /* number of external internet interfaces */
 
+static int
+in_domifattach(struct ifnet *ifp)
+{
+       int error;
+
+       if ((error = proto_plumb(PF_INET, ifp)) && error != EEXIST)
+               log(LOG_ERR, "%s: proto_plumb returned %d if=%s%d\n",
+                   __func__, error, ifp->if_name, ifp->if_unit);
+
+       return (error);
+}
+
 /*
  * Generic internet control operations (ioctl's).
  * Ifp is 0 if not an interface-specific ioctl.
@@ -331,6 +383,8 @@ in_control(
        struct kev_msg        ev_msg;
        struct kev_in_data    in_event_data;
 
+       bzero(&in_event_data, sizeof(struct kev_in_data));
+       bzero(&ev_msg, sizeof(struct kev_msg));
        switch (cmd) {
        case SIOCALIFADDR:
        case SIOCDLIFADDR:
@@ -354,19 +408,24 @@ in_control(
                for (iap = in_ifaddrhead.tqh_first; iap; 
                     iap = iap->ia_link.tqe_next)
                        if (iap->ia_ifp == ifp) {
+                               IFA_LOCK(&iap->ia_ifa);
                                if (((struct sockaddr_in *)&ifr->ifr_addr)->sin_addr.s_addr ==
                                    iap->ia_addr.sin_addr.s_addr) {
                                        ia = iap;
+                                       IFA_UNLOCK(&iap->ia_ifa);
                                        break;
                                } else if (ia == NULL) {
                                        ia = iap;
-                                       if (ifr->ifr_addr.sa_family != AF_INET)
+                                       if (ifr->ifr_addr.sa_family != AF_INET) {
+                                               IFA_UNLOCK(&iap->ia_ifa);
                                                break;
+                                       }
                                }
+                               IFA_UNLOCK(&iap->ia_ifa);
                        }
                /* take a reference on ia before releasing lock */
                if (ia != NULL) {
-                       ifaref(&ia->ia_ifa);
+                       IFA_ADDREF(&ia->ia_ifa);
                }
                lck_rw_done(in_ifaddr_rwlock);
        }
@@ -393,19 +452,19 @@ in_control(
 
                        lck_rw_lock_shared(in_ifaddr_rwlock);
                        for (oia = ia; ia; ia = ia->ia_link.tqe_next) {
+                               IFA_LOCK(&ia->ia_ifa);
                                if (ia->ia_ifp == ifp  &&
                                    ia->ia_addr.sin_addr.s_addr ==
-                                   ifra->ifra_addr.sin_addr.s_addr)
+                                   ifra->ifra_addr.sin_addr.s_addr) {
+                                       IFA_ADDREF_LOCKED(&ia->ia_ifa);
+                                       IFA_UNLOCK(&ia->ia_ifa);
                                        break;
-                       }
-                       /* take a reference on ia before releasing lock */
-                       if (ia != NULL && ia != oia) {
-                               ifaref(&ia->ia_ifa);
+                               }
+                               IFA_UNLOCK(&ia->ia_ifa);
                        }
                        lck_rw_done(in_ifaddr_rwlock);
-                       if (oia != NULL && oia != ia) {
-                               ifafree(&oia->ia_ifa);
-                       }
+                       if (oia != NULL)
+                               IFA_REMREF(&oia->ia_ifa);
                        if ((ifp->if_flags & IFF_POINTOPOINT)
                            && (cmd == SIOCAIFADDR)
                            && (ifra->ifra_dstaddr.sin_addr.s_addr
@@ -426,7 +485,13 @@ in_control(
        case SIOCSIFADDR:
        case SIOCSIFNETMASK:
        case SIOCSIFDSTADDR:
-               if ((so->so_state & SS_PRIV) == 0) {
+               /* socket is NULL if called from in_purgeaddrs() */
+               if (so != NULL && (so->so_state & SS_PRIV) == 0) {
+                       error = EPERM;
+                       goto done;
+               }
+               /* in case it's NULL, make sure it came from the kernel */
+               if (so == NULL && p != kernproc) {
                        error = EPERM;
                        goto done;
                }
@@ -439,21 +504,22 @@ in_control(
                        error = EINVAL;
                        goto done;
                }
-               if (ia == (struct in_ifaddr *)0) {
+               if (ia == NULL) {
                        ia = in_ifaddr_alloc(M_WAITOK);
-                       if (ia == (struct in_ifaddr *)NULL) {
+                       if (ia == NULL) {
                                error = ENOBUFS;
                                goto done;
                        }
-                       IA_HASH_INIT(ia);
+                       ifnet_lock_exclusive(ifp);
                        ifa = &ia->ia_ifa;
+                       IFA_LOCK(ifa);
                        /* Hold a reference for this routine */
-                       ifaref(ifa);
+                       IFA_ADDREF_LOCKED(ifa);
+                       IA_HASH_INIT(ia);
                        ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr;
                        ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
                        ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask;
                        ia->ia_sockmask.sin_len = 8;
-                       ifnet_lock_exclusive(ifp);
                        if (ifp->if_flags & IFF_BROADCAST) {
                                ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
                                ia->ia_broadaddr.sin_family = AF_INET;
@@ -463,22 +529,25 @@ in_control(
                                in_interfaces++;
                        /* if_attach_ifa() holds a reference for ifa_link */
                        if_attach_ifa(ifp, ifa);
+                       /*
+                        * If we have to go through in_ifinit(), make sure
+                        * to avoid installing route(s) based on this address
+                        * via PFC_IFUP event, before the link resolver (ARP)
+                        * initializes it.
+                        */
+                       if (cmd == SIOCAIFADDR || cmd == SIOCSIFADDR)
+                               ifa->ifa_debug |= IFD_NOTREADY;
+                       IFA_UNLOCK(ifa);
                        ifnet_lock_done(ifp);
                        lck_rw_lock_exclusive(in_ifaddr_rwlock);
                        /* Hold a reference for ia_link */
-                       ifaref(ifa);
+                       IFA_ADDREF(ifa);
                        TAILQ_INSERT_TAIL(&in_ifaddrhead, ia, ia_link);
                        lck_rw_done(in_ifaddr_rwlock);
-
-                       /* Generic protocol plumbing */
-
-                       if ((error = proto_plumb(PF_INET, ifp))) {
-                               if (error != EEXIST) {
-                                       kprintf("in.c: warning can't plumb proto if=%s%d type %d error=%d\n",
-                                               ifp->if_name, ifp->if_unit, ifp->if_type, error);
-                               }
-                               error = 0; /*discard error, can be cold with unsupported interfaces */
-                       }
+                       error = in_domifattach(ifp);
+                       /* discard error,can be cold with unsupported interfaces */
+                       if (error)
+                               error = 0;
                }
                break;
 
@@ -531,7 +600,9 @@ in_control(
                break;
 
        case SIOCGIFADDR:
+               IFA_LOCK(&ia->ia_ifa);
                *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
+               IFA_UNLOCK(&ia->ia_ifa);
                break;
 
        case SIOCGIFBRDADDR:
@@ -539,7 +610,9 @@ in_control(
                        error = EINVAL;
                        break;
                }
+               IFA_LOCK(&ia->ia_ifa);
                *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
+               IFA_UNLOCK(&ia->ia_ifa);
                break;
 
        case SIOCGIFDSTADDR:
@@ -547,11 +620,15 @@ in_control(
                        error = EINVAL;
                        break;
                }
+               IFA_LOCK(&ia->ia_ifa);
                *((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
+               IFA_UNLOCK(&ia->ia_ifa);
                break;
 
        case SIOCGIFNETMASK:
+               IFA_LOCK(&ia->ia_ifa);
                *((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
+               IFA_UNLOCK(&ia->ia_ifa);
                break;
 
        case SIOCSIFDSTADDR:
@@ -559,23 +636,28 @@ in_control(
                        error = EINVAL;
                        break;
                }
+               IFA_LOCK(&ia->ia_ifa);
                oldaddr = ia->ia_dstaddr;
                ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
                if (ia->ia_dstaddr.sin_family == AF_INET)
                        ia->ia_dstaddr.sin_len = sizeof (struct sockaddr_in);
+               IFA_UNLOCK(&ia->ia_ifa);
                error = ifnet_ioctl(ifp, PF_INET, SIOCSIFDSTADDR, ia);
+               IFA_LOCK(&ia->ia_ifa);
                if (error == EOPNOTSUPP) {
                        error = 0;
                }
                if (error) {
                        ia->ia_dstaddr = oldaddr;
+                       IFA_UNLOCK(&ia->ia_ifa);
                        break;
                }
+               IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);
 
                ev_msg.vendor_code    = KEV_VENDOR_APPLE;
                ev_msg.kev_class      = KEV_NETWORK_CLASS;
                ev_msg.kev_subclass   = KEV_INET_SUBCLASS;
-       
+
                ev_msg.event_code = KEV_INET_SIFDSTADDR;
 
                if (ia->ia_ifa.ifa_dstaddr)
@@ -590,6 +672,7 @@ in_control(
                in_event_data.ia_subnet       = ia->ia_subnet;
                in_event_data.ia_subnetmask   = ia->ia_subnetmask;
                in_event_data.ia_netbroadcast = ia->ia_netbroadcast;
+               IFA_UNLOCK(&ia->ia_ifa);
                strncpy(&in_event_data.link_data.if_name[0], ifp->if_name, IFNAMSIZ);
                in_event_data.link_data.if_family = ifp->if_family;
                in_event_data.link_data.if_unit  = (u_int32_t) ifp->if_unit;
@@ -600,14 +683,22 @@ in_control(
 
                kev_post_msg(&ev_msg);
 
-
+               lck_mtx_lock(rnh_lock);
+               IFA_LOCK(&ia->ia_ifa);
                if (ia->ia_flags & IFA_ROUTE) {
                        ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
-                       rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
+                       IFA_UNLOCK(&ia->ia_ifa);
+                       rtinit_locked(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
+                       IFA_LOCK(&ia->ia_ifa);
                        ia->ia_ifa.ifa_dstaddr =
-                                       (struct sockaddr *)&ia->ia_dstaddr;
-                       rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
+                           (struct sockaddr *)&ia->ia_dstaddr;
+                       IFA_UNLOCK(&ia->ia_ifa);
+                       rtinit_locked(&(ia->ia_ifa), (int)RTM_ADD,
+                           RTF_HOST|RTF_UP);
+               } else {
+                       IFA_UNLOCK(&ia->ia_ifa);
                }
+               lck_mtx_unlock(rnh_lock);
                break;
 
        case SIOCSIFBRDADDR:
@@ -615,12 +706,13 @@ in_control(
                        error = EINVAL;
                        break;
                }
+               IFA_LOCK(&ia->ia_ifa);
                ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
 
                ev_msg.vendor_code    = KEV_VENDOR_APPLE;
                ev_msg.kev_class      = KEV_NETWORK_CLASS;
                ev_msg.kev_subclass   = KEV_INET_SUBCLASS;
-       
+
                ev_msg.event_code = KEV_INET_SIFBRDADDR;
 
                if (ia->ia_ifa.ifa_dstaddr)
@@ -635,6 +727,7 @@ in_control(
                in_event_data.ia_subnet       = ia->ia_subnet;
                in_event_data.ia_subnetmask   = ia->ia_subnetmask;
                in_event_data.ia_netbroadcast = ia->ia_netbroadcast;
+               IFA_UNLOCK(&ia->ia_ifa);
                strncpy(&in_event_data.link_data.if_name[0], ifp->if_name, IFNAMSIZ);
                in_event_data.link_data.if_family = ifp->if_family;
                in_event_data.link_data.if_unit  = (u_int32_t) ifp->if_unit;
@@ -661,34 +754,41 @@ in_control(
                break;
 
        case SIOCPROTOATTACH:
-               error = proto_plumb(PF_INET, ifp);
+               error = in_domifattach(ifp);
                break;
-                
+
        case SIOCPROTODETACH:
-                // if an ip address is still present, refuse to detach
+                /*
+                * If an IPv4 address is still present, refuse to detach.
+                */
                ifnet_lock_shared(ifp);
-               TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 
-                       if (ifa->ifa_addr->sa_family == AF_INET)
+               TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+                       IFA_LOCK(ifa);
+                       if (ifa->ifa_addr->sa_family == AF_INET) {
+                               IFA_UNLOCK(ifa);
                                break;
+                       }
+                       IFA_UNLOCK(ifa);
+               }
                ifnet_lock_done(ifp);
-               if (ifa != 0) {
+               if (ifa != NULL) {
                        error =  EBUSY;
                        break;
                }
 
                error = proto_unplumb(PF_INET, ifp);
                break;
-               
 
        case SIOCSIFNETMASK: {
                u_long i;
-               
+
                i = ifra->ifra_addr.sin_addr.s_addr;
+               IFA_LOCK(&ia->ia_ifa);
                ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr = i);
                ev_msg.vendor_code    = KEV_VENDOR_APPLE;
                ev_msg.kev_class      = KEV_NETWORK_CLASS;
                ev_msg.kev_subclass   = KEV_INET_SUBCLASS;
-       
+
                ev_msg.event_code = KEV_INET_SIFNETMASK;
 
                if (ia->ia_ifa.ifa_dstaddr)
@@ -703,6 +803,7 @@ in_control(
                in_event_data.ia_subnet       = ia->ia_subnet;
                in_event_data.ia_subnetmask   = ia->ia_subnetmask;
                in_event_data.ia_netbroadcast = ia->ia_netbroadcast;
+               IFA_UNLOCK(&ia->ia_ifa);
                strncpy(&in_event_data.link_data.if_name[0], ifp->if_name, IFNAMSIZ);
                in_event_data.link_data.if_family = ifp->if_family;
                in_event_data.link_data.if_unit  = (u_int32_t) ifp->if_unit;
@@ -720,6 +821,7 @@ in_control(
                hostIsNew = 1;
                error = 0;
 
+               IFA_LOCK(&ia->ia_ifa);
                if (ia->ia_addr.sin_family == AF_INET) {
                        if (ifra->ifra_addr.sin_len == 0) {
                                ifra->ifra_addr = ia->ia_addr;
@@ -729,7 +831,9 @@ in_control(
                                hostIsNew = 0;
                }
                if (ifra->ifra_mask.sin_len) {
+                       IFA_UNLOCK(&ia->ia_ifa);
                        in_ifscrub(ifp, ia, 0);
+                       IFA_LOCK(&ia->ia_ifa);
                        ia->ia_sockmask = ifra->ifra_mask;
                        ia->ia_subnetmask =
                             ntohl(ia->ia_sockmask.sin_addr.s_addr);
@@ -737,19 +841,25 @@ in_control(
                }
                if ((ifp->if_flags & IFF_POINTOPOINT) &&
                    (ifra->ifra_dstaddr.sin_family == AF_INET)) {
+                       IFA_UNLOCK(&ia->ia_ifa);
                        in_ifscrub(ifp, ia, 0);
+                       IFA_LOCK(&ia->ia_ifa);
                        ia->ia_dstaddr = ifra->ifra_dstaddr;
                        ia->ia_dstaddr.sin_len = sizeof (struct sockaddr_in);
                        maskIsNew  = 1; /* We lie; but the effect's the same */
                }
                if (ifra->ifra_addr.sin_family == AF_INET &&
                    (hostIsNew || maskIsNew)) {
+                       IFA_UNLOCK(&ia->ia_ifa);
                        error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
+               } else {
+                       IFA_UNLOCK(&ia->ia_ifa);
                }
 #if PF
                if (!error)
                        (void) pf_ifaddr_hook(ifp, cmd);
 #endif /* PF */
+               IFA_LOCK(&ia->ia_ifa);
                if ((ifp->if_flags & IFF_BROADCAST) &&
                    (ifra->ifra_broadaddr.sin_family == AF_INET))
                        ia->ia_broadaddr = ifra->ifra_broadaddr;
@@ -780,6 +890,7 @@ in_control(
                     in_event_data.ia_subnet       = ia->ia_subnet;
                     in_event_data.ia_subnetmask   = ia->ia_subnetmask;
                     in_event_data.ia_netbroadcast = ia->ia_netbroadcast;
+                    IFA_UNLOCK(&ia->ia_ifa);
                     strncpy(&in_event_data.link_data.if_name[0], ifp->if_name, IFNAMSIZ);
                     in_event_data.link_data.if_family = ifp->if_family;
                     in_event_data.link_data.if_unit  = (u_int32_t) ifp->if_unit;
@@ -789,6 +900,8 @@ in_control(
                     ev_msg.dv[1].data_length = 0;
 
                     kev_post_msg(&ev_msg);
+               } else {
+                    IFA_UNLOCK(&ia->ia_ifa);
                }
                break;
 
@@ -804,9 +917,10 @@ in_control(
                ev_msg.vendor_code    = KEV_VENDOR_APPLE;
                ev_msg.kev_class      = KEV_NETWORK_CLASS;
                ev_msg.kev_subclass   = KEV_INET_SUBCLASS;
-               
+
                ev_msg.event_code = KEV_INET_ADDR_DELETED;
 
+               IFA_LOCK(&ia->ia_ifa);
                if (ia->ia_ifa.ifa_dstaddr)
                     in_event_data.ia_dstaddr = 
                          ((struct sockaddr_in *)ia->ia_ifa.ifa_dstaddr)->sin_addr;
@@ -819,6 +933,7 @@ in_control(
                in_event_data.ia_subnet       = ia->ia_subnet;
                in_event_data.ia_subnetmask   = ia->ia_subnetmask;
                in_event_data.ia_netbroadcast = ia->ia_netbroadcast;
+               IFA_UNLOCK(&ia->ia_ifa);
                strncpy(&in_event_data.link_data.if_name[0], ifp->if_name, IFNAMSIZ);
                in_event_data.link_data.if_family = ifp->if_family;
                in_event_data.link_data.if_unit  = (u_int32_t) ifp->if_unit;
@@ -830,10 +945,12 @@ in_control(
                ifa = &ia->ia_ifa;
                lck_rw_lock_exclusive(in_ifaddr_rwlock);
                /* Release ia_link reference */
-               ifafree(ifa);
+               IFA_REMREF(ifa);
                TAILQ_REMOVE(&in_ifaddrhead, ia, ia_link);
+               IFA_LOCK(ifa);
                if (IA_IS_HASHED(ia))
                        in_iahash_remove(ia);
+               IFA_UNLOCK(ifa);
                lck_rw_done(in_ifaddr_rwlock);
 
                /*
@@ -841,31 +958,42 @@ in_control(
                 */
                in_ifscrub(ifp, ia, 0);
                ifnet_lock_exclusive(ifp);
+               IFA_LOCK(ifa);
                /* if_detach_ifa() releases ifa_link reference */
                if_detach_ifa(ifp, ifa);
-#ifdef __APPLE__
+               /* Our reference to this address is dropped at the bottom */
+               IFA_UNLOCK(ifa);
+
               /*
                * If the interface supports multicast, and no address is left,
                * remove the "all hosts" multicast group from that interface.
                */
-               if (ifp->if_flags & IFF_MULTICAST) {
-                       struct in_addr addr;
-                       struct in_multi *inm = NULL;
+               if ((ifp->if_flags & IFF_MULTICAST) != 0 ||
+                       ifp->if_allhostsinm != NULL ) {
 
-                       TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 
-                               if (ifa->ifa_addr->sa_family == AF_INET)
+                       TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+                               IFA_LOCK(ifa);
+                               if (ifa->ifa_addr->sa_family == AF_INET) {
+                                       IFA_UNLOCK(ifa);
                                        break;
-
-                       if (ifa == 0) {
-                               addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
-                               IN_LOOKUP_MULTI(addr, ifp, inm);
+                               }
+                               IFA_UNLOCK(ifa);
                        }
                        ifnet_lock_done(ifp);
-                       if (inm)
-                               in_delmulti(&inm);
-               } else 
+
+                       lck_mtx_lock(&ifp->if_addrconfig_lock);
+                       if (ifa == NULL && ifp->if_allhostsinm != NULL) {
+                               struct in_multi *inm = ifp->if_allhostsinm;
+                               ifp->if_allhostsinm = NULL;
+
+                               in_delmulti(inm);
+                               /* release the reference for allhostsinm pointer */
+                               INM_REMREF(inm); 
+                       }
+                       lck_mtx_unlock(&ifp->if_addrconfig_lock);
+               } else {
                        ifnet_lock_done(ifp);
-#endif
+               }
 
                /* Post the kernel event */
                kev_post_msg(&ev_msg);
@@ -881,7 +1009,7 @@ in_control(
                                error = 0;
 
                        /* Release reference from ifa_ifpgetprimary() */
-                       ifafree(ifa);
+                       IFA_REMREF(ifa);
                }
 #if PF
                (void) pf_ifaddr_hook(ifp, cmd);
@@ -933,7 +1061,6 @@ in_control(
 
             /* Multicast options */
             if (cloned_inp->inp_moptions != NULL) {
-                int                    i;
                 struct ip_moptions     *cloned_imo = cloned_inp->inp_moptions;
                 struct ip_moptions     *imo = inp->inp_moptions;
 
@@ -942,35 +1069,15 @@ in_control(
                      * No multicast option buffer attached to the pcb;
                      * allocate one.
                      */
-                    imo = (struct ip_moptions*)
-                        _MALLOC(sizeof(*imo), M_IPMOPTS, M_WAITOK);
+                    imo = ip_allocmoptions(M_WAITOK);
                     if (imo == NULL) {
                         error2 = ENOBUFS;
                         break;
                     }
                     inp->inp_moptions = imo;
                 }
-                imo->imo_multicast_ifp = cloned_imo->imo_multicast_ifp;
-                imo->imo_multicast_vif = cloned_imo->imo_multicast_vif;
-                imo->imo_multicast_ttl = cloned_imo->imo_multicast_ttl;
-                imo->imo_multicast_loop = cloned_imo->imo_multicast_loop;
-                imo->imo_num_memberships = cloned_imo->imo_num_memberships;
-                for (i = 0; i < cloned_imo->imo_num_memberships; i++) {
-                    imo->imo_membership[i] =
-                    in_addmulti(&cloned_imo->imo_membership[i]->inm_addr,
-                                cloned_imo->imo_membership[i]->inm_ifp);
-                                       if (imo->imo_membership[i] == NULL) {
-                                               error2 = ENOBUFS;
-                                               break;
-                                       }
-                }
-                if (i < cloned_imo->imo_num_memberships) {
-                       /* Failed, perform cleanup */
-                       for (i--; i >= 0; i--)
-                               in_delmulti(&imo->imo_membership[i]);
-                       imo->imo_num_memberships = 0;
-                       break;
-                }
+
+               error2 = imo_clone(cloned_imo, imo);
             }
         }
         break;
@@ -982,7 +1089,7 @@ in_control(
        }
  done:
        if (ia != NULL) {
-               ifafree(&ia->ia_ifa);
+               IFA_REMREF(&ia->ia_ifa);
        }
        return (error);
 }
@@ -1017,7 +1124,7 @@ in_lifaddr_ioctl(
        /* sanity checks */
        if (!data || !ifp) {
                panic("invalid argument to in_lifaddr_ioctl");
-               /*NOTRECHED*/
+               /*NOTREACHED*/
        }
 
        switch (cmd) {
@@ -1112,21 +1219,30 @@ in_lifaddr_ioctl(
 
                ifnet_lock_shared(ifp);
                TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
-                       if (ifa->ifa_addr->sa_family != AF_INET6)
+                       IFA_LOCK(ifa);
+                       if (ifa->ifa_addr->sa_family != AF_INET6) {
+                               IFA_UNLOCK(ifa);
                                continue;
-                       if (!cmp)
+                       }
+                       if (!cmp) {
+                               IFA_UNLOCK(ifa);
                                break;
+                       }
                        candidate.s_addr = ((struct sockaddr_in *)&ifa->ifa_addr)->sin_addr.s_addr;
                        candidate.s_addr &= mask.s_addr;
+                       IFA_UNLOCK(ifa);
                        if (candidate.s_addr == match.s_addr)
                                break;
                }
+               if (ifa != NULL)
+                       IFA_ADDREF(ifa);
                ifnet_lock_done(ifp);
                if (!ifa)
                        return EADDRNOTAVAIL;
                ia = (struct in_ifaddr *)ifa;
 
                if (cmd == SIOCGLIFADDR) {
+                       IFA_LOCK(ifa);
                        /* fill in the if_laddrreq structure */
                        bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin_len);
 
@@ -1141,6 +1257,8 @@ in_lifaddr_ioctl(
 
                        iflr->flags = 0;        /*XXX*/
 
+                       IFA_UNLOCK(ifa);
+                       IFA_REMREF(ifa);
                        return 0;
                } else {
                        struct in_aliasreq ifra;
@@ -1150,6 +1268,7 @@ in_lifaddr_ioctl(
                        bcopy(iflr->iflr_name, ifra.ifra_name,
                                sizeof(ifra.ifra_name));
 
+                       IFA_LOCK(ifa);
                        bcopy(&ia->ia_addr, &ifra.ifra_addr,
                                ia->ia_addr.sin_len);
                        if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
@@ -1158,7 +1277,8 @@ in_lifaddr_ioctl(
                        }
                        bcopy(&ia->ia_sockmask, &ifra.ifra_dstaddr,
                                ia->ia_sockmask.sin_len);
-
+                       IFA_UNLOCK(ifa);
+                       IFA_REMREF(ifa);
                        return in_control(so, SIOCDIFADDR, (caddr_t)&ifra,
                                          ifp, p);
                }
@@ -1172,21 +1292,23 @@ in_lifaddr_ioctl(
  * Delete any existing route for an interface.
  */
 void
-in_ifscrub(
-       struct ifnet *ifp,
-       struct in_ifaddr *ia,
-       int locked)
+in_ifscrub(struct ifnet *ifp, struct in_ifaddr *ia, int locked)
 {
-
-       if ((ia->ia_flags & IFA_ROUTE) == 0)
+       IFA_LOCK(&ia->ia_ifa);
+       if ((ia->ia_flags & IFA_ROUTE) == 0) {
+               IFA_UNLOCK(&ia->ia_ifa);
                return;
+       }
+       IFA_UNLOCK(&ia->ia_ifa);
        if (!locked)
                lck_mtx_lock(rnh_lock);
        if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
                rtinit_locked(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
        else
                rtinit_locked(&(ia->ia_ifa), (int)RTM_DELETE, 0);
+       IFA_LOCK(&ia->ia_ifa);
        ia->ia_flags &= ~IFA_ROUTE;
+       IFA_UNLOCK(&ia->ia_ifa);
        if (!locked)
                lck_mtx_unlock(rnh_lock);
 }
@@ -1197,12 +1319,20 @@ in_ifscrub(
 static void
 in_iahash_remove(struct in_ifaddr *ia)
 {
-       if (!IA_IS_HASHED(ia))
-               panic("attempt to remove wrong ia %p from hash table\n", ia);
+        lck_rw_assert(in_ifaddr_rwlock, LCK_RW_ASSERT_EXCLUSIVE);
+       IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);
 
+       if (!IA_IS_HASHED(ia)) {
+               panic("attempt to remove wrong ia %p from hash table\n", ia);
+               /* NOTREACHED */
+       }
        TAILQ_REMOVE(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
        IA_HASH_INIT(ia);
-       ifafree(&ia->ia_ifa);
+       if (IFA_REMREF_LOCKED(&ia->ia_ifa) == NULL) {
+               panic("%s: unexpected (missing) refcnt ifa=%p", __func__,
+                   &ia->ia_ifa);
+               /* NOTREACHED */
+       }
 }
 
 /*
@@ -1211,13 +1341,18 @@ in_iahash_remove(struct in_ifaddr *ia)
 static void
 in_iahash_insert(struct in_ifaddr *ia)
 {
-       if (ia->ia_addr.sin_family != AF_INET)
+        lck_rw_assert(in_ifaddr_rwlock, LCK_RW_ASSERT_EXCLUSIVE);
+       IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);
+
+       if (ia->ia_addr.sin_family != AF_INET) {
                panic("attempt to insert wrong ia %p into hash table\n", ia);
-       else if (IA_IS_HASHED(ia))
+               /* NOTREACHED */
+       } else if (IA_IS_HASHED(ia)) {
                panic("attempt to double-insert ia %p into hash table\n", ia);
-
+               /* NOTREACHED */
+       }
        TAILQ_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
-       ifaref(&ia->ia_ifa);
+       IFA_ADDREF_LOCKED(&ia->ia_ifa);
 }
 
 /*
@@ -1236,22 +1371,39 @@ in_iahash_insert_ptp(struct in_ifaddr *ia)
        struct in_ifaddr *tmp_ifa;
        struct ifnet *tmp_ifp;
 
-       if (ia->ia_addr.sin_family != AF_INET)
+        lck_rw_assert(in_ifaddr_rwlock, LCK_RW_ASSERT_EXCLUSIVE);
+       IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);
+
+       if (ia->ia_addr.sin_family != AF_INET) {
                panic("attempt to insert wrong ia %p into hash table\n", ia);
-       else if (IA_IS_HASHED(ia))
+               /* NOTREACHED */
+       } else if (IA_IS_HASHED(ia)) {
                panic("attempt to double-insert ia %p into hash table\n", ia);
-        
-       TAILQ_FOREACH(tmp_ifa, INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia_hash)
-               if (IA_SIN(tmp_ifa)->sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr)
+               /* NOTREACHED */
+       }
+       IFA_UNLOCK(&ia->ia_ifa);
+       TAILQ_FOREACH(tmp_ifa, INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
+           ia_hash) {
+               IFA_LOCK(&tmp_ifa->ia_ifa);
+               /* ia->ia_addr won't change, so check without lock */
+               if (IA_SIN(tmp_ifa)->sin_addr.s_addr ==
+                   ia->ia_addr.sin_addr.s_addr) {
+                       IFA_UNLOCK(&tmp_ifa->ia_ifa);
                        break;
+               }
+               IFA_UNLOCK(&tmp_ifa->ia_ifa);
+       }
        tmp_ifp = (tmp_ifa == NULL) ? NULL : tmp_ifa->ia_ifp;
 
-       if (tmp_ifp == NULL)
-               TAILQ_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
-       else
-               TAILQ_INSERT_TAIL(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, ia_hash);
-       
-       ifaref(&ia->ia_ifa);
+       IFA_LOCK(&ia->ia_ifa);
+       if (tmp_ifp == NULL) {
+               TAILQ_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
+                   ia, ia_hash);
+       } else {
+               TAILQ_INSERT_TAIL(INADDR_HASH(ia->ia_addr.sin_addr.s_addr),
+                   ia, ia_hash);
+       }
+       IFA_ADDREF_LOCKED(&ia->ia_ifa);
 }
 
 /*
@@ -1273,9 +1425,10 @@ in_ifinit(
        int oldremoved = 0;
 
        /* Take an extra reference for this routine */
-       ifaref(&ia->ia_ifa);
+       IFA_ADDREF(&ia->ia_ifa);
 
        lck_rw_lock_exclusive(in_ifaddr_rwlock);
+       IFA_LOCK(&ia->ia_ifa);
        oldaddr = ia->ia_addr;
        if (IA_IS_HASHED(ia)) {
                oldremoved = 1;
@@ -1285,8 +1438,9 @@ in_ifinit(
        ia->ia_addr.sin_len = sizeof (*sin);
        if ((ifp->if_flags & IFF_POINTOPOINT))
                in_iahash_insert_ptp(ia);
-       else    
+       else
                in_iahash_insert(ia);
+       IFA_UNLOCK(&ia->ia_ifa);
        lck_rw_done(in_ifaddr_rwlock);
 
        /*
@@ -1315,10 +1469,11 @@ in_ifinit(
        }
 
        /* Release reference from ifa_ifpgetprimary() */
-       ifafree(ifa0);
+       IFA_REMREF(ifa0);
 
        if (error) {
                lck_rw_lock_exclusive(in_ifaddr_rwlock);
+               IFA_LOCK(&ia->ia_ifa);
                if (IA_IS_HASHED(ia))
                        in_iahash_remove(ia);
                ia->ia_addr = oldaddr;
@@ -1328,17 +1483,27 @@ in_ifinit(
                        else
                                in_iahash_insert(ia);
                }
+               IFA_UNLOCK(&ia->ia_ifa);
                lck_rw_done(in_ifaddr_rwlock);
                /* Release extra reference taken above */
-               ifafree(&ia->ia_ifa);
+               IFA_REMREF(&ia->ia_ifa);
                return (error);
        }
        lck_mtx_lock(rnh_lock);
+       IFA_LOCK(&ia->ia_ifa);
+       /*
+        * Address has been initialized by the link resolver (ARP)
+        * via ifnet_ioctl() above; it may now generate route(s).
+        */
+       ia->ia_ifa.ifa_debug &= ~IFD_NOTREADY;
        if (scrub) {
                ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
+               IFA_UNLOCK(&ia->ia_ifa);
                in_ifscrub(ifp, ia, 1);
+               IFA_LOCK(&ia->ia_ifa);
                ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
        }
+       IFA_LOCK_ASSERT_HELD(&ia->ia_ifa);
        if (IN_CLASSA(i))
                ia->ia_netmask = IN_CLASSA_NET;
        else if (IN_CLASSB(i))
@@ -1372,16 +1537,21 @@ in_ifinit(
                flags |= RTF_HOST;
        } else if (ifp->if_flags & IFF_POINTOPOINT) {
                if (ia->ia_dstaddr.sin_family != AF_INET) {
+                       IFA_UNLOCK(&ia->ia_ifa);
                        lck_mtx_unlock(rnh_lock);
                        /* Release extra reference taken above */
-                       ifafree(&ia->ia_ifa);
+                       IFA_REMREF(&ia->ia_ifa);
                        return (0);
                }
                ia->ia_dstaddr.sin_len = sizeof (*sin);
                flags |= RTF_HOST;
        }
-       if ((error = rtinit_locked(&(ia->ia_ifa), (int)RTM_ADD, flags)) == 0)
+       IFA_UNLOCK(&ia->ia_ifa);
+       if ((error = rtinit_locked(&(ia->ia_ifa), (int)RTM_ADD, flags)) == 0) {
+               IFA_LOCK(&ia->ia_ifa);
                ia->ia_flags |= IFA_ROUTE;
+               IFA_UNLOCK(&ia->ia_ifa);
+       }
        lck_mtx_unlock(rnh_lock);
 
        /* XXX check if the subnet route points to the same interface */
@@ -1393,19 +1563,29 @@ in_ifinit(
         * multicast group on that interface.
         */
        if (ifp->if_flags & IFF_MULTICAST) {
-               struct in_multi *inm;
                struct in_addr addr;
 
+               lck_mtx_lock(&ifp->if_addrconfig_lock);
                addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
-               ifnet_lock_shared(ifp);
-               IN_LOOKUP_MULTI(addr, ifp, inm);
-               ifnet_lock_done(ifp);
-               if (inm == 0)
-                       in_addmulti(&addr, ifp);
+               if (ifp->if_allhostsinm == NULL) {
+                       struct in_multi *inm;
+                       inm = in_addmulti(&addr, ifp);
+
+                       if (inm != NULL) {
+                               /* keep the reference on inm added by 
+                                * in_addmulti above for storing the 
+                                * pointer in allhostsinm 
+                                */
+                               ifp->if_allhostsinm = inm;
+                       } else {
+                               printf("Failed to add membership to all-hosts multicast address on interface %s%d\n", ifp->if_name, ifp->if_unit);
+                       }
+               }
+               lck_mtx_unlock(&ifp->if_addrconfig_lock);
        }
 
        /* Release extra reference taken above */
-       ifafree(&ia->ia_ifa);
+       IFA_REMREF(&ia->ia_ifa);
        return (error);
 }
 
@@ -1414,18 +1594,15 @@ in_ifinit(
  * Return 1 if the address might be a local broadcast address.
  */
 int
-in_broadcast(
-       struct in_addr in,
-       struct ifnet *ifp)
+in_broadcast(struct in_addr in, struct ifnet *ifp)
 {
        struct ifaddr *ifa;
        u_int32_t t;
 
-       if (in.s_addr == INADDR_BROADCAST ||
-           in.s_addr == INADDR_ANY)
-               return 1;
+       if (in.s_addr == INADDR_BROADCAST || in.s_addr == INADDR_ANY)
+               return (1);
        if ((ifp->if_flags & IFF_BROADCAST) == 0)
-               return 0;
+               return (0);
        t = ntohl(in.s_addr);
        /*
         * Look through the list of addresses for a match
@@ -1434,10 +1611,7 @@ in_broadcast(
 #define ia ((struct in_ifaddr *)ifa)
        ifnet_lock_shared(ifp);
        TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
-               if (ifa->ifa_addr == NULL) {
-                       ifnet_lock_done(ifp);
-                       return (0);
-               }
+               IFA_LOCK(ifa);
                if (ifa->ifa_addr->sa_family == AF_INET &&
                    (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
                     in.s_addr == ia->ia_netbroadcast.s_addr ||
@@ -1451,140 +1625,76 @@ in_broadcast(
                      * address.
                      */
                     ia->ia_subnetmask != (u_int32_t)0xffffffff) {
+                       IFA_UNLOCK(ifa);
                        ifnet_lock_done(ifp);
-                       return 1;
+                       return (1);
                }
+               IFA_UNLOCK(ifa);
        }
        ifnet_lock_done(ifp);
        return (0);
 #undef ia
 }
 
-static void
-in_free_inm(
-       void*   ifma_protospec)
-{
-       struct in_multi *inm = ifma_protospec;
-       
-       /*
-        * No remaining claims to this record; let IGMP know that
-        * we are leaving the multicast group.
-        */
-       igmp_leavegroup(inm);
-       lck_mtx_lock(rnh_lock);
-       LIST_REMOVE(inm, inm_link);
-       lck_mtx_unlock(rnh_lock);
-       FREE(inm, M_IPMADDR);
-}
-
-/*
- * Add an address to the list of IP multicast addresses for a given interface.
- */
-struct in_multi *
-in_addmulti(
-       struct in_addr *ap,
-       struct ifnet *ifp)
+void
+in_purgeaddrs(struct ifnet *ifp)
 {
-       struct in_multi *inm;
-       int error;
-       struct sockaddr_in sin;
-       struct ifmultiaddr *ifma;
+       struct ifaddr **ifap;
+       int err, i;
 
        /*
-        * Call generic routine to add membership or increment
-        * refcount.  It wants addresses in the form of a sockaddr,
-        * so we build one here (being careful to zero the unused bytes).
+        * Be nice, and try the civilized way first.  If we can't get
+        * rid of them this way, then do it the rough way.  We must
+        * only get here during detach time, after the ifnet has been
+        * removed from the global list and arrays.
         */
-       bzero(&sin, sizeof sin);
-       sin.sin_family = AF_INET;
-       sin.sin_len = sizeof sin;
-       sin.sin_addr = *ap;
-       error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma);
-       if (error) {
-               return 0;
-       }
-
-       /*
-        * If ifma->ifma_protospec is null, then if_addmulti() created
-        * a new record.  Otherwise, we are done.
-        */
-       if (ifma->ifma_protospec != 0) {
-               return ifma->ifma_protospec;
-       }
-
-       inm = (struct in_multi *) _MALLOC(sizeof(*inm), M_IPMADDR, M_WAITOK);
-       if (inm == NULL) {
-               return (NULL);
-       }
-
-       bzero(inm, sizeof *inm);
-       inm->inm_addr = *ap;
-       inm->inm_ifp = ifp;
-       inm->inm_ifma = ifma;
-       lck_mtx_lock(rnh_lock);
-       if (ifma->ifma_protospec == NULL) {
-               ifma->ifma_protospec = inm;
-               ifma->ifma_free = in_free_inm;
-               LIST_INSERT_HEAD(&in_multihead, inm, inm_link);
-       }
-       lck_mtx_unlock(rnh_lock);
-       
-       if (ifma->ifma_protospec != inm) {
-               _FREE(inm, M_IPMADDR);
-               return ifma->ifma_protospec;
-       }
-
-       /*
-        * Let IGMP know that we have joined a new IP multicast group.
-        */
-       error = igmp_joingroup(inm);
-       if (error) {
-               char addrbuf[16];
-               
-               /*
-                * We can't free the inm because someone else may already be
-                * using it. Once we put it in to ifma->ifma_protospec, it
-                * must exist as long as the ifma does. Might be nice to flag
-                * the error so we can try igmp_joingroup the next time through.
-                */
-               log(LOG_ERR, "igmp_joingroup error %d joining multicast %s on %s%d\n",
-                       error, inet_ntop(AF_INET, &sin.sin_addr, addrbuf, sizeof(addrbuf)),
-                       ifp->if_name, ifp->if_unit);
-       }
-       
-       return (inm);
-}
-
-/*
- * Delete a multicast address record.
- */
-void
-in_delmulti(
-       struct in_multi **inm)
-{
-       struct in_multi *inm2;
-       
-       lck_mtx_lock(rnh_lock);
-       LIST_FOREACH(inm2, &in_multihead, inm_link) {
-               if (inm2 == *inm)
-                       break;
-       }
-       if (inm2 != *inm) {
-               lck_mtx_unlock(rnh_lock);
-               printf("in_delmulti - ignoring invalid inm (%p)\n", *inm);
-               return;
-       }
-       lck_mtx_unlock(rnh_lock);
-       
-       /* We intentionally do this a bit differently than BSD */
-       if ((*inm)->inm_ifma) {
-               if_delmultiaddr((*inm)->inm_ifma, 0);
-               ifma_release((*inm)->inm_ifma);
+       err = ifnet_get_address_list_family_internal(ifp, &ifap, AF_INET, 1,
+           M_WAITOK);
+       if (err == 0 && ifap != NULL) {
+               for (i = 0; ifap[i] != NULL; i++) {
+                       struct ifaliasreq ifr;
+                       struct ifaddr *ifa;
+
+                       ifa = ifap[i];
+                       bzero(&ifr, sizeof (ifr));
+                       IFA_LOCK(ifa);
+                       ifr.ifra_addr = *ifa->ifa_addr;
+                       if (ifa->ifa_dstaddr != NULL)
+                               ifr.ifra_broadaddr = *ifa->ifa_dstaddr;
+                       IFA_UNLOCK(ifa);
+                       err = in_control(NULL, SIOCDIFADDR, (caddr_t)&ifr, ifp,
+                           kernproc);
+                       /* if we lost the race, ignore it */
+                       if (err == EADDRNOTAVAIL)
+                               err = 0;
+                       if (err != 0) {
+                               char s_addr[MAX_IPv4_STR_LEN];
+                               char s_dstaddr[MAX_IPv4_STR_LEN];
+                               struct in_addr *s, *d;
+
+                               IFA_LOCK(ifa);
+                               s = &((struct sockaddr_in *)
+                                   ifa->ifa_addr)->sin_addr;
+                               d = &((struct sockaddr_in *)
+                                   ifa->ifa_dstaddr)->sin_addr;
+                               (void) inet_ntop(AF_INET, &s->s_addr, s_addr,
+                                   sizeof (s_addr));
+                               (void) inet_ntop(AF_INET, &d->s_addr, s_dstaddr,
+                                   sizeof (s_dstaddr));
+                               IFA_UNLOCK(ifa);
+
+                               printf("%s: SIOCDIFADDR ifp=%p ifa_addr=%s "
+                                   "ifa_dstaddr=%s (err=%d)\n", __func__, ifp,
+                                   s_addr, s_dstaddr, err);
+                       }
+               }
+               ifnet_free_address_list(ifap);
+       } else if (err != 0 && err != ENXIO) {
+               printf("%s: error retrieving list of AF_INET addresses for "
+                   "ifp=%p (err=%d)\n", __func__, ifp, err);
        }
-       *inm = NULL;
 }
 
-#if !NFSCLIENT
 int inet_aton(char *cp, struct in_addr *pin);
 int
 inet_aton(char * cp, struct in_addr * pin)
@@ -1605,7 +1715,19 @@ inet_aton(char * cp, struct in_addr * pin)
     }
     return (TRUE);
 }
-#endif
+
+int inet_ntoa2(struct in_addr * pin, char * cp, const int len);
+int inet_ntoa2(struct in_addr * pin, char * cp, const int len)
+{
+    int ret;
+
+    /* address is in network byte order */
+   ret = snprintf(cp, len, "%u.%u.%u.%u", pin->s_addr & 0xFF, 
+                  (pin->s_addr >> 8) & 0xFF, (pin->s_addr >> 16) & 0xFF,
+                  (pin->s_addr >> 24) & 0xFF);
+
+   return ret < len ? TRUE : FALSE;
+}
 
 /*
  * Called as part of ip_init
@@ -1613,6 +1735,8 @@ inet_aton(char * cp, struct in_addr * pin)
 void
 in_ifaddr_init(void)
 {
+       in_multi_init();
+
        PE_parse_boot_argn("ifa_debug", &inifa_debug, sizeof (inifa_debug));
 
        inifa_size = (inifa_debug == 0) ? sizeof (struct in_ifaddr) :
@@ -1620,10 +1744,15 @@ in_ifaddr_init(void)
 
        inifa_zone = zinit(inifa_size, INIFA_ZONE_MAX * inifa_size,
            0, INIFA_ZONE_NAME);
-       if (inifa_zone == NULL)
+       if (inifa_zone == NULL) {
                panic("%s: failed allocating %s", __func__, INIFA_ZONE_NAME);
-
+               /* NOTREACHED */
+       }
        zone_change(inifa_zone, Z_EXPAND, TRUE);
+       zone_change(inifa_zone, Z_CALLERACCT, FALSE);
+
+       lck_mtx_init(&inifa_trash_lock, ifa_mtx_grp, ifa_mtx_attr);
+       TAILQ_INIT(&inifa_trash_head);
 }
 
 static struct in_ifaddr *
@@ -1637,11 +1766,14 @@ in_ifaddr_alloc(int how)
                bzero(inifa, inifa_size);
                inifa->ia_ifa.ifa_free = in_ifaddr_free;
                inifa->ia_ifa.ifa_debug |= IFD_ALLOC;
+               ifa_lock_init(&inifa->ia_ifa);
                if (inifa_debug != 0) {
                        struct in_ifaddr_dbg *inifa_dbg =
                            (struct in_ifaddr_dbg *)inifa;
                        inifa->ia_ifa.ifa_debug |= IFD_DEBUG;
                        inifa->ia_ifa.ifa_trace = in_ifaddr_trace;
+                       inifa->ia_ifa.ifa_attached = in_ifaddr_attached;
+                       inifa->ia_ifa.ifa_detached = in_ifaddr_detached;
                        ctrace_record(&inifa_dbg->inifa_alloc);
                }
        }
@@ -1651,21 +1783,79 @@ in_ifaddr_alloc(int how)
 static void
 in_ifaddr_free(struct ifaddr *ifa)
 {
-       if (ifa->ifa_refcnt != 0)
+       IFA_LOCK_ASSERT_HELD(ifa);
+
+       if (ifa->ifa_refcnt != 0) {
                panic("%s: ifa %p bad ref cnt", __func__, ifa);
-       if (!(ifa->ifa_debug & IFD_ALLOC))
+               /* NOTREACHED */
+       } if (!(ifa->ifa_debug & IFD_ALLOC)) {
                panic("%s: ifa %p cannot be freed", __func__, ifa);
-
+               /* NOTREACHED */
+       }
        if (ifa->ifa_debug & IFD_DEBUG) {
                struct in_ifaddr_dbg *inifa_dbg = (struct in_ifaddr_dbg *)ifa;
                ctrace_record(&inifa_dbg->inifa_free);
                bcopy(&inifa_dbg->inifa, &inifa_dbg->inifa_old,
                    sizeof (struct in_ifaddr));
+               if (ifa->ifa_debug & IFD_TRASHED) {
+                       /* Become a regular mutex, just in case */
+                       IFA_CONVERT_LOCK(ifa);
+                       lck_mtx_lock(&inifa_trash_lock);
+                       TAILQ_REMOVE(&inifa_trash_head, inifa_dbg,
+                           inifa_trash_link);
+                       lck_mtx_unlock(&inifa_trash_lock);
+                       ifa->ifa_debug &= ~IFD_TRASHED;
+               }
        }
+       IFA_UNLOCK(ifa);
+       ifa_lock_destroy(ifa);
        bzero(ifa, sizeof (struct in_ifaddr));
        zfree(inifa_zone, ifa);
 }
 
+static void
+in_ifaddr_attached(struct ifaddr *ifa)
+{
+       struct in_ifaddr_dbg *inifa_dbg = (struct in_ifaddr_dbg *)ifa;
+
+       IFA_LOCK_ASSERT_HELD(ifa);
+
+       if (!(ifa->ifa_debug & IFD_DEBUG)) {
+               panic("%s: ifa %p has no debug structure", __func__, ifa);
+               /* NOTREACHED */
+       }
+       if (ifa->ifa_debug & IFD_TRASHED) {
+               /* Become a regular mutex, just in case */
+               IFA_CONVERT_LOCK(ifa);
+               lck_mtx_lock(&inifa_trash_lock);
+               TAILQ_REMOVE(&inifa_trash_head, inifa_dbg, inifa_trash_link);
+               lck_mtx_unlock(&inifa_trash_lock);
+               ifa->ifa_debug &= ~IFD_TRASHED;
+       }
+}
+
+static void
+in_ifaddr_detached(struct ifaddr *ifa)
+{
+       struct in_ifaddr_dbg *inifa_dbg = (struct in_ifaddr_dbg *)ifa;
+
+       IFA_LOCK_ASSERT_HELD(ifa);
+
+       if (!(ifa->ifa_debug & IFD_DEBUG)) {
+               panic("%s: ifa %p has no debug structure", __func__, ifa);
+               /* NOTREACHED */
+       } else if (ifa->ifa_debug & IFD_TRASHED) {
+               panic("%s: ifa %p is already in trash list", __func__, ifa);
+               /* NOTREACHED */
+       }
+       ifa->ifa_debug |= IFD_TRASHED;
+       /* Become a regular mutex, just in case */
+       IFA_CONVERT_LOCK(ifa);
+       lck_mtx_lock(&inifa_trash_lock);
+       TAILQ_INSERT_TAIL(&inifa_trash_head, inifa_dbg, inifa_trash_link);
+       lck_mtx_unlock(&inifa_trash_lock);
+}
+
 static void
 in_ifaddr_trace(struct ifaddr *ifa, int refhold)
 {
@@ -1674,9 +1864,10 @@ in_ifaddr_trace(struct ifaddr *ifa, int refhold)
        u_int32_t idx;
        u_int16_t *cnt;
 
-       if (!(ifa->ifa_debug & IFD_DEBUG))
+       if (!(ifa->ifa_debug & IFD_DEBUG)) {
                panic("%s: ifa %p has no debug structure", __func__, ifa);
-
+               /* NOTREACHED */
+       }
        if (refhold) {
                cnt = &inifa_dbg->inifa_refhold_cnt;
                tr = inifa_dbg->inifa_refhold;
@@ -1685,6 +1876,6 @@ in_ifaddr_trace(struct ifaddr *ifa, int refhold)
                tr = inifa_dbg->inifa_refrele;
        }
 
-       idx = OSAddAtomic16(1, (volatile SInt16 *)cnt) % CTRACE_HIST_SIZE;
+       idx = atomic_add_16_ov(cnt, 1) % INIFA_TRACE_HIST_SIZE;
        ctrace_record(&tr[idx]);
 }