xnu-1228.tar.gz

[apple/xnu.git] / bsd / netinet / in_arp.c

diff --git a/bsd/netinet/in_arp.c b/bsd/netinet/in_arp.c
index 44c5263955581792eee7e0ab447bc44b8fbe69fc..d764b37182ab27444d8d926dc0c3c640126eda07 100644 (file)
--- a/bsd/netinet/in_arp.c
+++ b/bsd/netinet/in_arp.c
@@ -1,23 +1,29 @@
 /*
 /*

- * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2004-2007 Apple Inc. All rights reserved.

  *
  *

- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

  * 
  * 

- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.

  * 
  * 

- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER

  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,

- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.

  * 
  * 

- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@

  */
 /*
  * Copyright (c) 1982, 1989, 1993
  */
 /*
  * Copyright (c) 1982, 1989, 1993


@@ -79,7 +85,7 @@
 static const size_t MAX_HW_LEN = 10;
 
 SYSCTL_DECL(_net_link_ether);
 static const size_t MAX_HW_LEN = 10;
 
 SYSCTL_DECL(_net_link_ether);

-SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW, 0, "");
+SYSCTL_NODE(_net_link_ether, PF_INET, inet, CTLFLAG_RW|CTLFLAG_LOCKED, 0, "");

 
 /* timer values */
 static int arpt_prune = (5*60*1); /* walk list every 5 minutes */
 
 /* timer values */
 static int arpt_prune = (5*60*1); /* walk list every 5 minutes */


@@ -115,6 +121,7 @@ static int  arp_inuse, arp_allocated;
 static int     arp_maxtries = 5;
 static int     useloopback = 1; /* use loopback interface for local traffic */
 static int     arp_proxyall = 0;
 static int     arp_maxtries = 5;
 static int     useloopback = 1; /* use loopback interface for local traffic */
 static int     arp_proxyall = 0;

+static int     arp_sendllconflict = 0;

 
 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
           &arp_maxtries, 0, "");
 
 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, maxtries, CTLFLAG_RW,
           &arp_maxtries, 0, "");


@@ -122,6 +129,8 @@ SYSCTL_INT(_net_link_ether_inet, OID_AUTO, useloopback, CTLFLAG_RW,
           &useloopback, 0, "");
 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
           &arp_proxyall, 0, "");
           &useloopback, 0, "");
 SYSCTL_INT(_net_link_ether_inet, OID_AUTO, proxyall, CTLFLAG_RW,
           &arp_proxyall, 0, "");

+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, sendllconflict, CTLFLAG_RW,
+          &arp_sendllconflict, 0, "");

 
 static int log_arp_warnings = 0;
 
 
 static int log_arp_warnings = 0;
 


@@ -129,6 +138,16 @@ SYSCTL_INT(_net_link_ether_inet, OID_AUTO, log_arp_warnings, CTLFLAG_RW,
        &log_arp_warnings, 0,
        "log arp warning messages");
 
        &log_arp_warnings, 0,
        "log arp warning messages");
 

+static int keep_announcements = 1;
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, keep_announcements, CTLFLAG_RW,
+       &keep_announcements, 0,
+       "keep arp announcements");
+
+static int send_conflicting_probes = 1;
+SYSCTL_INT(_net_link_ether_inet, OID_AUTO, send_conflicting_probes, CTLFLAG_RW,
+       &send_conflicting_probes, 0,
+       "send conflicting link-local arp probes");
+

 extern u_int32_t       ipv4_ll_arp_aware;
 
 /*
 extern u_int32_t       ipv4_ll_arp_aware;
 
 /*


@@ -159,14 +178,14 @@ arptfree(
  */
 /* ARGSUSED */
 static void
  */
 /* ARGSUSED */
 static void

-arptimer(
-       __unused void *ignored_arg)
+arptimer(void *ignored_arg)

 {
 {

-       struct llinfo_arp *la = llinfo_arp.lh_first;
-       struct llinfo_arp *ola;
+#pragma unused (ignored_arg)
+       struct llinfo_arp *la, *ola;

        struct timeval timenow;
 
        lck_mtx_lock(rt_mtx);
        struct timeval timenow;
 
        lck_mtx_lock(rt_mtx);

+       la = llinfo_arp.lh_first;

        getmicrotime(&timenow);
        while ((ola = la) != 0) {
                struct rtentry *rt = la->la_rt;
        getmicrotime(&timenow);
        while ((ola = la) != 0) {
                struct rtentry *rt = la->la_rt;


@@ -296,7 +315,7 @@ arp_rtrequest(
                        rt->rt_expire = 0;
                        ifnet_lladdr_copy_bytes(rt->rt_ifp, LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6);
                        if (useloopback)
                        rt->rt_expire = 0;
                        ifnet_lladdr_copy_bytes(rt->rt_ifp, LLADDR(SDL(gate)), SDL(gate)->sdl_alen = 6);
                        if (useloopback)

-                               rt->rt_ifp = loif;
+                               rt->rt_ifp = lo_ifp;

 
                }
                break;
 
                }
                break;


@@ -306,7 +325,7 @@ arp_rtrequest(
                        break;
                arp_inuse--;
                LIST_REMOVE(la, la_le);
                        break;
                arp_inuse--;
                LIST_REMOVE(la, la_le);

-               rt->rt_llinfo = 0;
+               rt->rt_llinfo = NULL;

                rt->rt_flags &= ~RTF_LLINFO;
                if (la->la_hold) {
                        m_freem(la->la_hold);
                rt->rt_flags &= ~RTF_LLINFO;
                if (la->la_hold) {
                        m_freem(la->la_hold);


@@ -324,7 +343,7 @@ sdl_addr_to_hex(const struct sockaddr_dl *sdl, char * orig_buf, int buflen)
 {
        char *          buf = orig_buf;
        int             i;
 {
        char *          buf = orig_buf;
        int             i;

-       const u_char *  lladdr = sdl->sdl_data;
+       const u_char *  lladdr = (u_char *)sdl->sdl_data;

        int                     maxbytes = buflen / 3;
        
        if (maxbytes > sdl->sdl_alen) {
        int                     maxbytes = buflen / 3;
        
        if (maxbytes > sdl->sdl_alen) {


@@ -354,7 +373,7 @@ arp_lookup_route(
        route_t *route)
 {
        struct sockaddr_inarp sin = {sizeof(sin), AF_INET, 0, {0}, {0}, 0, 0};
        route_t *route)
 {
        struct sockaddr_inarp sin = {sizeof(sin), AF_INET, 0, {0}, {0}, 0, 0};

-       const char *why = 0;
+       const char *why = NULL;

        errno_t error = 0;
        
        // Caller is responsible for taking the routing lock
        errno_t error = 0;
        
        // Caller is responsible for taking the routing lock


@@ -363,7 +382,7 @@ arp_lookup_route(
        sin.sin_addr.s_addr = addr->s_addr;
        sin.sin_other = proxy ? SIN_PROXY : 0;
        
        sin.sin_addr.s_addr = addr->s_addr;
        sin.sin_other = proxy ? SIN_PROXY : 0;
        

-       *route = rtalloc1_locked((const struct sockaddr*)&sin, create, 0);
+       *route = rtalloc1_locked((struct sockaddr*)&sin, create, 0);

        if (*route == NULL)
                return ENETUNREACH;
        
        if (*route == NULL)
                return ENETUNREACH;
        


@@ -422,9 +441,9 @@ arp_route_to_gateway_route(
        route_t hint,
        route_t *out_route)
 {
        route_t hint,
        route_t *out_route)
 {

+       struct timeval timenow;

        route_t route = hint;
        *out_route = NULL;
        route_t route = hint;
        *out_route = NULL;

-       struct timeval timenow;

        
        /* If we got a hint from the higher layers, check it out */
        if (route) {
        
        /* If we got a hint from the higher layers, check it out */
        if (route) {


@@ -592,7 +611,7 @@ arp_lookup_ip(
                                route->rt_flags |= RTF_REJECT;
                                route->rt_rmx.rmx_expire += arpt_down;
                                llinfo->la_asked = 0;
                                route->rt_flags |= RTF_REJECT;
                                route->rt_rmx.rmx_expire += arpt_down;
                                llinfo->la_asked = 0;

-                               llinfo->la_hold = 0;
+                               llinfo->la_hold = NULL;

                                lck_mtx_unlock(rt_mtx);
                                return EHOSTUNREACH;
                        }
                                lck_mtx_unlock(rt_mtx);
                                return EHOSTUNREACH;
                        }


@@ -618,8 +637,8 @@ arp_ip_handle_input(
        route_t route = NULL;
        char buf[3 * MAX_HW_LEN]; // enough for MAX_HW_LEN byte hw address
        struct llinfo_arp *llinfo;
        route_t route = NULL;
        char buf[3 * MAX_HW_LEN]; // enough for MAX_HW_LEN byte hw address
        struct llinfo_arp *llinfo;

-       struct timeval timenow;

        errno_t error;
        errno_t error;

+       int created_announcement = 0;

        
        /* Do not respond to requests for 0.0.0.0 */
        if (target_ip->sin_addr.s_addr == 0 && arpop == ARPOP_REQUEST) {
        
        /* Do not respond to requests for 0.0.0.0 */
        if (target_ip->sin_addr.s_addr == 0 && arpop == ARPOP_REQUEST) {


@@ -689,10 +708,15 @@ arp_ip_handle_input(
         */
        error = arp_lookup_route(&sender_ip->sin_addr, (target_ip->sin_addr.s_addr ==
                                best_ia->ia_addr.sin_addr.s_addr), 0, &route);
         */
        error = arp_lookup_route(&sender_ip->sin_addr, (target_ip->sin_addr.s_addr ==
                                best_ia->ia_addr.sin_addr.s_addr), 0, &route);

-       

        if (error || route == 0 || route->rt_gateway == 0) {
        if (error || route == 0 || route->rt_gateway == 0) {

-               if (ipv4_ll_arp_aware != 0 && IN_LINKLOCAL(target_ip->sin_addr.s_addr)
-                       && arpop == ARPOP_REQUEST && sender_ip->sin_addr.s_addr == 0) {
+               if (arpop != ARPOP_REQUEST) {
+                       goto respond;
+               }
+               if (arp_sendllconflict
+                   && send_conflicting_probes != 0
+                   && (ifp->if_eflags & IFEF_ARPLL) != 0 
+                   && IN_LINKLOCAL(ntohl(target_ip->sin_addr.s_addr))
+                   && sender_ip->sin_addr.s_addr == 0) {

                        /*
                         * Verify this ARP probe doesn't conflict with an IPv4LL we know of
                         * on another interface.
                        /*
                         * Verify this ARP probe doesn't conflict with an IPv4LL we know of
                         * on another interface.


@@ -700,28 +724,29 @@ arp_ip_handle_input(
                        error = arp_lookup_route(&target_ip->sin_addr, 0, 0, &route);
                        if (error == 0 && route && route->rt_gateway) {
                                gateway = SDL(route->rt_gateway);
                        error = arp_lookup_route(&target_ip->sin_addr, 0, 0, &route);
                        if (error == 0 && route && route->rt_gateway) {
                                gateway = SDL(route->rt_gateway);

-                               if (route->rt_ifp != ifp &&
-                                       (gateway->sdl_alen != sender_hw->sdl_alen ||
-                                        bcmp(CONST_LLADDR(gateway), CONST_LLADDR(sender_hw),
-                                        gateway->sdl_alen) != 0)) {
+                               if (route->rt_ifp != ifp && gateway->sdl_alen != 0 
+                                   && (gateway->sdl_alen != sender_hw->sdl_alen 
+                                       || bcmp(CONST_LLADDR(gateway), CONST_LLADDR(sender_hw),
+                                               gateway->sdl_alen) != 0)) {

                                        /*
                                         * A node is probing for an IPv4LL we know exists on a
                                         * different interface. We respond with a conflicting probe
                                         * to force the new device to pick a different IPv4LL
                                         * address.
                                         */
                                        /*
                                         * A node is probing for an IPv4LL we know exists on a
                                         * different interface. We respond with a conflicting probe
                                         * to force the new device to pick a different IPv4LL
                                         * address.
                                         */

-                                       log(LOG_INFO,
+                                       if (log_arp_warnings) {
+                                           log(LOG_INFO,

                                                "arp: %s on %s%d sent probe for %s, already on %s%d\n",
                                                sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
                                                ifp->if_name, ifp->if_unit,
                                                inet_ntop(AF_INET, &target_ip->sin_addr, ipv4str,
                                                                  sizeof(ipv4str)),
                                                route->rt_ifp->if_name, route->rt_ifp->if_unit);
                                                "arp: %s on %s%d sent probe for %s, already on %s%d\n",
                                                sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
                                                ifp->if_name, ifp->if_unit,
                                                inet_ntop(AF_INET, &target_ip->sin_addr, ipv4str,
                                                                  sizeof(ipv4str)),
                                                route->rt_ifp->if_name, route->rt_ifp->if_unit);

-                                       log(LOG_INFO,
+                                           log(LOG_INFO,

                                                "arp: sending conflicting probe to %s on %s%d\n",
                                                sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
                                                ifp->if_name, ifp->if_unit);
                                                "arp: sending conflicting probe to %s on %s%d\n",
                                                sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
                                                ifp->if_name, ifp->if_unit);

-                                       
+                                       }

                                        /*
                                         * Send a conservative unicast "ARP probe".
                                         * This should force the other device to pick a new number.
                                        /*
                                         * Send a conservative unicast "ARP probe".
                                         * This should force the other device to pick a new number.


@@ -735,14 +760,28 @@ arp_ip_handle_input(
                                                (const struct sockaddr*)target_ip);
                                }
                        }
                                                (const struct sockaddr*)target_ip);
                                }
                        }

+                       goto respond;
+               } else if (keep_announcements != 0
+                          && target_ip->sin_addr.s_addr == sender_ip->sin_addr.s_addr) {
+                       /* don't create entry if link-local address and link-local is disabled */
+                       if (!IN_LINKLOCAL(ntohl(sender_ip->sin_addr.s_addr)) 
+                           || (ifp->if_eflags & IFEF_ARPLL) != 0) {
+                               error = arp_lookup_route(&sender_ip->sin_addr, 1, 0, &route);
+                               if (error == 0 && route != NULL && route->rt_gateway != NULL) {
+                                       created_announcement = 1;
+                               }
+                       }
+                       if (created_announcement == 0) {
+                               goto respond;
+                       }
+               } else {
+                       goto respond;

                }
                }

-               
-               goto respond;

        }
        
        gateway = SDL(route->rt_gateway);
        if (route->rt_ifp != ifp) {
        }
        
        gateway = SDL(route->rt_gateway);
        if (route->rt_ifp != ifp) {

-               if (!IN_LINKLOCAL(sender_ip->sin_addr.s_addr) || (ifp->if_eflags & IFEF_ARPLL) == 0) {
+               if (!IN_LINKLOCAL(ntohl(sender_ip->sin_addr.s_addr)) || (ifp->if_eflags & IFEF_ARPLL) == 0) {

                        if (log_arp_warnings)
                                log(LOG_ERR, "arp: %s is on %s%d but got reply from %s on %s%d\n",
                                        inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
                        if (log_arp_warnings)
                                log(LOG_ERR, "arp: %s is on %s%d but got reply from %s on %s%d\n",
                                        inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,


@@ -776,22 +815,25 @@ arp_ip_handle_input(
        }
        
        if (gateway->sdl_alen && bcmp(LLADDR(gateway), CONST_LLADDR(sender_hw), gateway->sdl_alen)) {
        }
        
        if (gateway->sdl_alen && bcmp(LLADDR(gateway), CONST_LLADDR(sender_hw), gateway->sdl_alen)) {

-               if (route->rt_rmx.rmx_expire) {
+               if (route->rt_rmx.rmx_expire && log_arp_warnings) {

                        char buf2[3 * MAX_HW_LEN];
                        log(LOG_INFO, "arp: %s moved from %s to %s on %s%d\n",
                        char buf2[3 * MAX_HW_LEN];
                        log(LOG_INFO, "arp: %s moved from %s to %s on %s%d\n",

-                               inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
-                                                 sizeof(ipv4str)),
-                               sdl_addr_to_hex(gateway, buf, sizeof(buf)),
-                               sdl_addr_to_hex(sender_hw, buf2, sizeof(buf2)), ifp->if_name,
-                               ifp->if_unit);
+                           inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
+                           sizeof(ipv4str)),
+                           sdl_addr_to_hex(gateway, buf, sizeof(buf)),
+                           sdl_addr_to_hex(sender_hw, buf2, sizeof(buf2)),
+                           ifp->if_name, ifp->if_unit);

                }
                }

-               else {
-                       log(LOG_ERR,
-                               "arp: %s attempts to modify permanent entry for %s on %s%d\n",
-                               sdl_addr_to_hex(sender_hw, buf, sizeof(buf)),
-                               inet_ntop(AF_INET, &sender_ip->sin_addr, ipv4str,
-                                                 sizeof(ipv4str)),
-                               ifp->if_name, ifp->if_unit);
+               else if (route->rt_rmx.rmx_expire == 0) {
+                       if (log_arp_warnings) {
+                               log(LOG_ERR, "arp: %s attempts to modify "
+                                   "permanent entry for %s on %s%d\n",
+                                   sdl_addr_to_hex(sender_hw, buf,
+                                   sizeof(buf)),
+                                   inet_ntop(AF_INET, &sender_ip->sin_addr,
+                                   ipv4str, sizeof(ipv4str)),
+                                   ifp->if_name, ifp->if_unit);
+                       }

                        goto respond;
                }
        }
                        goto respond;
                }
        }


@@ -801,9 +843,12 @@ arp_ip_handle_input(
        bcopy(CONST_LLADDR(sender_hw), LLADDR(gateway), gateway->sdl_alen);
        
        /* Update the expire time for the route and clear the reject flag */
        bcopy(CONST_LLADDR(sender_hw), LLADDR(gateway), gateway->sdl_alen);
        
        /* Update the expire time for the route and clear the reject flag */

-       getmicrotime(&timenow);
-       if (route->rt_rmx.rmx_expire)
+       if (route->rt_rmx.rmx_expire) {
+               struct timeval timenow;
+
+               getmicrotime(&timenow);

                route->rt_rmx.rmx_expire = timenow.tv_sec + arpt_keep;
                route->rt_rmx.rmx_expire = timenow.tv_sec + arpt_keep;

+       }

        route->rt_flags &= ~RTF_REJECT;
        
        /* update the llinfo, send a queued packet if there is one */
        route->rt_flags &= ~RTF_REJECT;
        
        /* update the llinfo, send a queued packet if there is one */