freebsd-dev/sys/net/route.c
Bruce Evans fce002fdef Don't include <sys/ioctl.h> in the kernel. Stage 1: don't include
it when it is not used.  In most cases, the reasons for including it
went away when the special ioctl headers became self-sufficient.
1997-03-24 11:25:10 +00:00

1066 lines
27 KiB
C

/*
* Copyright (c) 1980, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)route.c 8.2 (Berkeley) 11/15/93
* $Id: route.c,v 1.41 1997/03/05 08:01:28 julian Exp $
*/
#include "opt_mrouting.h"
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <net/if.h>
#include <net/route.h>
#include <net/raw_cb.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/ip_mroute.h>
#define SA(p) ((struct sockaddr *)(p))
struct route_cb route_cb;
static struct rtstat rtstat;
struct radix_node_head *rt_tables[AF_MAX+1];
static int rttrash; /* routes not in table but not freed */
static void rt_maskedcopy __P((struct sockaddr *,
struct sockaddr *, struct sockaddr *));
static void rtable_init __P((void **));
static void
rtable_init(table)
void **table;
{
struct domain *dom;
for (dom = domains; dom; dom = dom->dom_next)
if (dom->dom_rtattach)
dom->dom_rtattach(&table[dom->dom_family],
dom->dom_rtoffset);
}
void
route_init()
{
rn_init(); /* initialize all zeroes, all ones, mask table */
rtable_init((void **)rt_tables);
}
/*
* Packet routing routines.
*/
void
rtalloc(ro)
register struct route *ro;
{
if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
return; /* XXX */
ro->ro_rt = rtalloc1(&ro->ro_dst, 1, 0UL);
}
void
rtalloc_ign(ro, ignore)
register struct route *ro;
u_long ignore;
{
if (ro->ro_rt && ro->ro_rt->rt_ifp && (ro->ro_rt->rt_flags & RTF_UP))
return; /* XXX */
ro->ro_rt = rtalloc1(&ro->ro_dst, 1, ignore);
}
/*
* Look up the route that matches the address given
* Or, at least try.. Create a cloned route if needed.
*/
struct rtentry *
rtalloc1(dst, report, ignflags)
register struct sockaddr *dst;
int report;
u_long ignflags;
{
register struct radix_node_head *rnh = rt_tables[dst->sa_family];
register struct rtentry *rt;
register struct radix_node *rn;
struct rtentry *newrt = 0;
struct rt_addrinfo info;
u_long nflags;
int s = splnet(), err = 0, msgtype = RTM_MISS;
/*
* Look up the address in the table for that Address Family
*/
if (rnh && (rn = rnh->rnh_matchaddr((caddr_t)dst, rnh)) &&
((rn->rn_flags & RNF_ROOT) == 0)) {
/*
* If we find it and it's not the root node, then
* get a refernce on the rtentry associated.
*/
newrt = rt = (struct rtentry *)rn;
nflags = rt->rt_flags & ~ignflags;
if (report && (nflags & (RTF_CLONING | RTF_PRCLONING))) {
/*
* We are apparently adding (report = 0 in delete).
* If it requires that it be cloned, do so.
* (This implies it wasn't a HOST route.)
*/
err = rtrequest(RTM_RESOLVE, dst, SA(0),
SA(0), 0, &newrt);
if (err) {
/*
* If the cloning didn't succeed, maybe
* what we have will do. Return that.
*/
newrt = rt;
rt->rt_refcnt++;
goto miss;
}
if ((rt = newrt) && (rt->rt_flags & RTF_XRESOLVE)) {
/*
* If the new route specifies it be
* externally resolved, then go do that.
*/
msgtype = RTM_RESOLVE;
goto miss;
}
} else
rt->rt_refcnt++;
} else {
/*
* Either we hit the root or couldn't find any match,
* Which basically means
* "caint get there frm here"
*/
rtstat.rts_unreach++;
miss: if (report) {
/*
* If required, report the failure to the supervising
* Authorities.
* For a delete, this is not an error. (report == 0)
*/
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
rt_missmsg(msgtype, &info, 0, err);
}
}
splx(s);
return (newrt);
}
/*
* Remove a reference count from an rtentry.
* If the count gets low enough, take it out of the routing table
*/
void
rtfree(rt)
register struct rtentry *rt;
{
/*
* find the tree for that address family
*/
register struct radix_node_head *rnh =
rt_tables[rt_key(rt)->sa_family];
register struct ifaddr *ifa;
if (rt == 0 || rnh == 0)
panic("rtfree");
/*
* decrement the reference count by one and if it reaches 0,
* and there is a close function defined, call the close function
*/
rt->rt_refcnt--;
if(rnh->rnh_close && rt->rt_refcnt == 0) {
rnh->rnh_close((struct radix_node *)rt, rnh);
}
/*
* If we are no longer "up" (and ref == 0)
* then we can free the resources associated
* with the route.
*/
if (rt->rt_refcnt <= 0 && (rt->rt_flags & RTF_UP) == 0) {
if (rt->rt_nodes->rn_flags & (RNF_ACTIVE | RNF_ROOT))
panic ("rtfree 2");
/*
* the rtentry must have been removed from the routing table
* so it is represented in rttrash.. remove that now.
*/
rttrash--;
#ifdef DIAGNOSTIC
if (rt->rt_refcnt < 0) {
printf("rtfree: %p not freed (neg refs)\n", rt);
return;
}
#endif
/*
* release references on items we hold them on..
* e.g other routes and ifaddrs.
*/
if((ifa = rt->rt_ifa))
IFAFREE(ifa);
if (rt->rt_parent) {
RTFREE(rt->rt_parent);
}
/*
* The key is separatly alloc'd so free it (see rt_setgate()).
* This also frees the gateway, as they are always malloc'd
* together.
*/
Free(rt_key(rt));
/*
* and the rtentry itself of course
*/
Free(rt);
}
}
void
ifafree(ifa)
register struct ifaddr *ifa;
{
if (ifa == NULL)
panic("ifafree");
if (ifa->ifa_refcnt == 0)
free(ifa, M_IFADDR);
else
ifa->ifa_refcnt--;
}
/*
* Force a routing table entry to the specified
* destination to go through the given gateway.
* Normally called as a result of a routing redirect
* message from the network layer.
*
* N.B.: must be called at splnet
*
*/
void
rtredirect(dst, gateway, netmask, flags, src, rtp)
struct sockaddr *dst, *gateway, *netmask, *src;
int flags;
struct rtentry **rtp;
{
register struct rtentry *rt;
int error = 0;
short *stat = 0;
struct rt_addrinfo info;
struct ifaddr *ifa;
/* verify the gateway is directly reachable */
if ((ifa = ifa_ifwithnet(gateway)) == 0) {
error = ENETUNREACH;
goto out;
}
rt = rtalloc1(dst, 0, 0UL);
/*
* If the redirect isn't from our current router for this dst,
* it's either old or wrong. If it redirects us to ourselves,
* we have a routing loop, perhaps as a result of an interface
* going down recently.
*/
#define equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0)
if (!(flags & RTF_DONE) && rt &&
(!equal(src, rt->rt_gateway) || rt->rt_ifa != ifa))
error = EINVAL;
else if (ifa_ifwithaddr(gateway))
error = EHOSTUNREACH;
if (error)
goto done;
/*
* Create a new entry if we just got back a wildcard entry
* or the the lookup failed. This is necessary for hosts
* which use routing redirects generated by smart gateways
* to dynamically build the routing tables.
*/
if ((rt == 0) || (rt_mask(rt) && rt_mask(rt)->sa_len < 2))
goto create;
/*
* Don't listen to the redirect if it's
* for a route to an interface.
*/
if (rt->rt_flags & RTF_GATEWAY) {
if (((rt->rt_flags & RTF_HOST) == 0) && (flags & RTF_HOST)) {
/*
* Changing from route to net => route to host.
* Create new route, rather than smashing route to net.
*/
create:
flags |= RTF_GATEWAY | RTF_DYNAMIC;
error = rtrequest((int)RTM_ADD, dst, gateway,
netmask, flags,
(struct rtentry **)0);
stat = &rtstat.rts_dynamic;
} else {
/*
* Smash the current notion of the gateway to
* this destination. Should check about netmask!!!
*/
rt->rt_flags |= RTF_MODIFIED;
flags |= RTF_MODIFIED;
stat = &rtstat.rts_newgateway;
/*
* add the key and gateway (in one malloc'd chunk).
*/
rt_setgate(rt, rt_key(rt), gateway);
}
} else
error = EHOSTUNREACH;
done:
if (rt) {
if (rtp && !error)
*rtp = rt;
else
rtfree(rt);
}
out:
if (error)
rtstat.rts_badredirect++;
else if (stat != NULL)
(*stat)++;
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = dst;
info.rti_info[RTAX_GATEWAY] = gateway;
info.rti_info[RTAX_NETMASK] = netmask;
info.rti_info[RTAX_AUTHOR] = src;
rt_missmsg(RTM_REDIRECT, &info, flags, error);
}
/*
* Routing table ioctl interface.
*/
int
rtioctl(req, data, p)
int req;
caddr_t data;
struct proc *p;
{
#ifdef INET
/* Multicast goop, grrr... */
#ifdef MROUTING
return mrt_ioctl(req, data);
#else
return mrt_ioctl(req, data, p);
#endif
#else /* INET */
return ENXIO;
#endif /* INET */
}
struct ifaddr *
ifa_ifwithroute(flags, dst, gateway)
int flags;
struct sockaddr *dst, *gateway;
{
register struct ifaddr *ifa;
if ((flags & RTF_GATEWAY) == 0) {
/*
* If we are adding a route to an interface,
* and the interface is a pt to pt link
* we should search for the destination
* as our clue to the interface. Otherwise
* we can use the local address.
*/
ifa = 0;
if (flags & RTF_HOST) {
ifa = ifa_ifwithdstaddr(dst);
}
if (ifa == 0)
ifa = ifa_ifwithaddr(gateway);
} else {
/*
* If we are adding a route to a remote net
* or host, the gateway may still be on the
* other end of a pt to pt link.
*/
ifa = ifa_ifwithdstaddr(gateway);
}
if (ifa == 0)
ifa = ifa_ifwithnet(gateway);
if (ifa == 0) {
struct rtentry *rt = rtalloc1(dst, 0, 0UL);
if (rt == 0)
return (0);
rt->rt_refcnt--;
if ((ifa = rt->rt_ifa) == 0)
return (0);
}
if (ifa->ifa_addr->sa_family != dst->sa_family) {
struct ifaddr *oifa = ifa;
ifa = ifaof_ifpforaddr(dst, ifa->ifa_ifp);
if (ifa == 0)
ifa = oifa;
}
return (ifa);
}
#define ROUNDUP(a) (a>0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
static int rt_fixdelete(struct radix_node *, void *);
static int rt_fixchange(struct radix_node *, void *);
struct rtfc_arg {
struct rtentry *rt0;
struct radix_node_head *rnh;
};
/*
* Do appropriate manipulations of a routing tree given
* all the bits of info needed
*/
int
rtrequest(req, dst, gateway, netmask, flags, ret_nrt)
int req, flags;
struct sockaddr *dst, *gateway, *netmask;
struct rtentry **ret_nrt;
{
int s = splnet(); int error = 0;
register struct rtentry *rt;
register struct radix_node *rn;
register struct radix_node_head *rnh;
struct ifaddr *ifa;
struct sockaddr *ndst;
#define senderr(x) { error = x ; goto bad; }
/*
* Find the correct routing tree to use for this Address Family
*/
if ((rnh = rt_tables[dst->sa_family]) == 0)
senderr(ESRCH);
/*
* If we are adding a host route then we don't want to put
* a netmask in the tree
*/
if (flags & RTF_HOST)
netmask = 0;
switch (req) {
case RTM_DELETE:
/*
* Remove the item from the tree and return it.
* Complain if it is not there and do no more processing.
*/
if ((rn = rnh->rnh_deladdr(dst, netmask, rnh)) == 0)
senderr(ESRCH);
if (rn->rn_flags & (RNF_ACTIVE | RNF_ROOT))
panic ("rtrequest delete");
rt = (struct rtentry *)rn;
/*
* Now search what's left of the subtree for any cloned
* routes which might have been formed from this node.
*/
if ((rt->rt_flags & RTF_PRCLONING) && netmask) {
rnh->rnh_walktree_from(rnh, dst, netmask,
rt_fixdelete, rt);
}
/*
* Remove any external references we may have.
* This might result in another rtentry being freed if
* we held it's last reference.
*/
if (rt->rt_gwroute) {
rt = rt->rt_gwroute;
RTFREE(rt);
(rt = (struct rtentry *)rn)->rt_gwroute = 0;
}
/*
* NB: RTF_UP must be set during the search above,
* because we might delete the last ref, causing
* rt to get freed prematurely.
* eh? then why not just add a reference?
* I'm not sure how RTF_UP helps matters. (JRE)
*/
rt->rt_flags &= ~RTF_UP;
/*
* give the protocol a chance to keep things in sync.
*/
if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
/*
* one more rtentry floating around that is not
* linked to the routing table.
*/
rttrash++;
/*
* If the caller wants it, then it can have it,
* but it's up to it to free the rtentry as we won't be
* doing it.
*/
if (ret_nrt)
*ret_nrt = rt;
else if (rt->rt_refcnt <= 0) {
rt->rt_refcnt++; /* make a 1->0 transition */
rtfree(rt);
}
break;
case RTM_RESOLVE:
if (ret_nrt == 0 || (rt = *ret_nrt) == 0)
senderr(EINVAL);
ifa = rt->rt_ifa;
flags = rt->rt_flags &
~(RTF_CLONING | RTF_PRCLONING | RTF_STATIC);
flags |= RTF_WASCLONED;
gateway = rt->rt_gateway;
if ((netmask = rt->rt_genmask) == 0)
flags |= RTF_HOST;
goto makeroute;
case RTM_ADD:
if ((flags & RTF_GATEWAY) && !gateway)
panic("rtrequest: GATEWAY but no gateway");
if ((ifa = ifa_ifwithroute(flags, dst, gateway)) == 0)
senderr(ENETUNREACH);
makeroute:
R_Malloc(rt, struct rtentry *, sizeof(*rt));
if (rt == 0)
senderr(ENOBUFS);
Bzero(rt, sizeof(*rt));
rt->rt_flags = RTF_UP | flags;
/*
* Add the gateway. Possibly re-malloc-ing the storage for it
* also add the rt_gwroute if possible.
*/
if (error = rt_setgate(rt, dst, gateway)) {
Free(rt);
senderr(error);
}
/*
* point to the (possibly newly malloc'd) dest address.
*/
ndst = rt_key(rt);
/*
* make sure it contains the value we want (masked if needed).
*/
if (netmask) {
rt_maskedcopy(dst, ndst, netmask);
} else
Bcopy(dst, ndst, dst->sa_len);
/*
* Note that we now have a reference to the ifa.
* This moved from below so that rnh->rnh_addaddr() can
* examine the ifa and ifa->ifa_ifp if it so desires.
*/
ifa->ifa_refcnt++;
rt->rt_ifa = ifa;
rt->rt_ifp = ifa->ifa_ifp;
rn = rnh->rnh_addaddr((caddr_t)ndst, (caddr_t)netmask,
rnh, rt->rt_nodes);
if (rn == 0) {
struct rtentry *rt2;
/*
* Uh-oh, we already have one of these in the tree.
* We do a special hack: if the route that's already
* there was generated by the protocol-cloning
* mechanism, then we just blow it away and retry
* the insertion of the new one.
*/
rt2 = rtalloc1(dst, 0, RTF_PRCLONING);
if (rt2 && rt2->rt_parent) {
rtrequest(RTM_DELETE,
(struct sockaddr *)rt_key(rt2),
rt2->rt_gateway,
rt_mask(rt2), rt2->rt_flags, 0);
RTFREE(rt2);
rn = rnh->rnh_addaddr((caddr_t)ndst,
(caddr_t)netmask,
rnh, rt->rt_nodes);
} else if (rt2) {
/* undo the extra ref we got */
RTFREE(rt2);
}
}
/*
* If it still failed to go into the tree,
* then un-make it (this should be a function)
*/
if (rn == 0) {
if (rt->rt_gwroute)
rtfree(rt->rt_gwroute);
if (rt->rt_ifa) {
IFAFREE(rt->rt_ifa);
}
Free(rt_key(rt));
Free(rt);
senderr(EEXIST);
}
rt->rt_parent = 0;
/*
* If we got here from RESOLVE, then we are cloning
* so clone the rest, and note that we
* are a clone (and increment the parent's references)
*/
if (req == RTM_RESOLVE) {
rt->rt_rmx = (*ret_nrt)->rt_rmx; /* copy metrics */
if ((*ret_nrt)->rt_flags & RTF_PRCLONING) {
rt->rt_parent = (*ret_nrt);
(*ret_nrt)->rt_refcnt++;
}
}
/*
* if this protocol has something to add to this then
* allow it to do that as well.
*/
if (ifa->ifa_rtrequest)
ifa->ifa_rtrequest(req, rt, SA(ret_nrt ? *ret_nrt : 0));
/*
* We repeat the same procedure from rt_setgate() here because
* it doesn't fire when we call it there because the node
* hasn't been added to the tree yet.
*/
if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != 0) {
struct rtfc_arg arg;
arg.rnh = rnh;
arg.rt0 = rt;
rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
rt_fixchange, &arg);
}
/*
* actually return a resultant rtentry and
* give the caller a single reference.
*/
if (ret_nrt) {
*ret_nrt = rt;
rt->rt_refcnt++;
}
break;
}
bad:
splx(s);
return (error);
}
/*
* Called from rtrequest(RTM_DELETE, ...) to fix up the route's ``family''
* (i.e., the routes related to it by the operation of cloning). This
* routine is iterated over all potential former-child-routes by way of
* rnh->rnh_walktree_from() above, and those that actually are children of
* the late parent (passed in as VP here) are themselves deleted.
*/
static int
rt_fixdelete(struct radix_node *rn, void *vp)
{
struct rtentry *rt = (struct rtentry *)rn;
struct rtentry *rt0 = vp;
if (rt->rt_parent == rt0 && !(rt->rt_flags & RTF_PINNED)) {
return rtrequest(RTM_DELETE, rt_key(rt),
(struct sockaddr *)0, rt_mask(rt),
rt->rt_flags, (struct rtentry **)0);
}
return 0;
}
/*
* This routine is called from rt_setgate() to do the analogous thing for
* adds and changes. There is the added complication in this case of a
* middle insert; i.e., insertion of a new network route between an older
* network route and (cloned) host routes. For this reason, a simple check
* of rt->rt_parent is insufficient; each candidate route must be tested
* against the (mask, value) of the new route (passed as before in vp)
* to see if the new route matches it. Unfortunately, this has the obnoxious
* property of also triggering for insertion /above/ a pre-existing network
* route and clones. Sigh. This may be fixed some day.
*
* XXX - it may be possible to do fixdelete() for changes and reserve this
* routine just for adds. I'm not sure why I thought it was necessary to do
* changes this way.
*/
#ifdef DEBUG
int rtfcdebug = 0;
#endif
static int
rt_fixchange(struct radix_node *rn, void *vp)
{
struct rtentry *rt = (struct rtentry *)rn;
struct rtfc_arg *ap = vp;
struct rtentry *rt0 = ap->rt0;
struct radix_node_head *rnh = ap->rnh;
u_char *xk1, *xm1, *xk2;
int i, len;
#ifdef DEBUG
if (rtfcdebug)
printf("rt_fixchange: rt %p, rt0 %p\n", rt, rt0);
#endif
if (!rt->rt_parent || (rt->rt_flags & RTF_PINNED)) {
#ifdef DEBUG
if(rtfcdebug) printf("no parent or pinned\n");
#endif
return 0;
}
if (rt->rt_parent == rt0) {
#ifdef DEBUG
if(rtfcdebug) printf("parent match\n");
#endif
return rtrequest(RTM_DELETE, rt_key(rt),
(struct sockaddr *)0, rt_mask(rt),
rt->rt_flags, (struct rtentry **)0);
}
/*
* There probably is a function somewhere which does this...
* if not, there should be.
*/
len = imin(((struct sockaddr *)rt_key(rt0))->sa_len,
((struct sockaddr *)rt_key(rt))->sa_len);
xk1 = (u_char *)rt_key(rt0);
xm1 = (u_char *)rt_mask(rt0);
xk2 = (u_char *)rt_key(rt);
for (i = rnh->rnh_treetop->rn_off; i < len; i++) {
if ((xk2[i] & xm1[i]) != xk1[i]) {
#ifdef DEBUG
if(rtfcdebug) printf("no match\n");
#endif
return 0;
}
}
/*
* OK, this node is a clone, and matches the node currently being
* changed/added under the node's mask. So, get rid of it.
*/
#ifdef DEBUG
if(rtfcdebug) printf("deleting\n");
#endif
return rtrequest(RTM_DELETE, rt_key(rt), (struct sockaddr *)0,
rt_mask(rt), rt->rt_flags, (struct rtentry **)0);
}
int
rt_setgate(rt0, dst, gate)
struct rtentry *rt0;
struct sockaddr *dst, *gate;
{
caddr_t new, old;
int dlen = ROUNDUP(dst->sa_len), glen = ROUNDUP(gate->sa_len);
register struct rtentry *rt = rt0;
struct radix_node_head *rnh = rt_tables[dst->sa_family];
/*
* A host route with the destination equal to the gateway
* will interfere with keeping LLINFO in the routing
* table, so disallow it.
*/
if (((rt0->rt_flags & (RTF_HOST|RTF_GATEWAY|RTF_LLINFO)) ==
(RTF_HOST|RTF_GATEWAY)) &&
(dst->sa_len == gate->sa_len) &&
(bcmp(dst, gate, dst->sa_len) == 0)) {
/*
* The route might already exist if this is an RTM_CHANGE
* or a routing redirect, so try to delete it.
*/
if (rt_key(rt0))
rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt0),
rt0->rt_gateway, rt_mask(rt0), rt0->rt_flags, 0);
return EADDRNOTAVAIL;
}
/*
* Both dst and gateway are stored in the same malloc'd chunk
* (If I ever get my hands on....)
* if we need to malloc a new chunk, then keep the old one around
* till we don't need it any more.
*/
if (rt->rt_gateway == 0 || glen > ROUNDUP(rt->rt_gateway->sa_len)) {
old = (caddr_t)rt_key(rt);
R_Malloc(new, caddr_t, dlen + glen);
if (new == 0)
return ENOBUFS;
rt->rt_nodes->rn_key = new;
} else {
/*
* otherwise just overwrite the old one
*/
new = rt->rt_nodes->rn_key;
old = 0;
}
/*
* copy the new gateway value into the memory chunk
*/
Bcopy(gate, (rt->rt_gateway = (struct sockaddr *)(new + dlen)), glen);
/*
* if we are replacing the chunk (or it's new) we need to
* replace the dst as well
*/
if (old) {
Bcopy(dst, new, dlen);
Free(old);
}
/*
* If there is already a gwroute, it's now almost definitly wrong
* so drop it.
*/
if (rt->rt_gwroute) {
rt = rt->rt_gwroute; RTFREE(rt);
rt = rt0; rt->rt_gwroute = 0;
}
/*
* Cloning loop avoidance:
* In the presence of protocol-cloning and bad configuration,
* it is possible to get stuck in bottomless mutual recursion
* (rtrequest rt_setgate rtalloc1). We avoid this by not allowing
* protocol-cloning to operate for gateways (which is probably the
* correct choice anyway), and avoid the resulting reference loops
* by disallowing any route to run through itself as a gateway.
* This is obviously mandatory when we get rt->rt_output().
*/
if (rt->rt_flags & RTF_GATEWAY) {
rt->rt_gwroute = rtalloc1(gate, 1, RTF_PRCLONING);
if (rt->rt_gwroute == rt) {
RTFREE(rt->rt_gwroute);
rt->rt_gwroute = 0;
return EDQUOT; /* failure */
}
}
/*
* This isn't going to do anything useful for host routes, so
* don't bother. Also make sure we have a reasonable mask
* (we don't yet have one during adds).
*/
if (!(rt->rt_flags & RTF_HOST) && rt_mask(rt) != 0) {
struct rtfc_arg arg;
arg.rnh = rnh;
arg.rt0 = rt;
rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
rt_fixchange, &arg);
}
return 0;
}
static void
rt_maskedcopy(src, dst, netmask)
struct sockaddr *src, *dst, *netmask;
{
register u_char *cp1 = (u_char *)src;
register u_char *cp2 = (u_char *)dst;
register u_char *cp3 = (u_char *)netmask;
u_char *cplim = cp2 + *cp3;
u_char *cplim2 = cp2 + *cp1;
*cp2++ = *cp1++; *cp2++ = *cp1++; /* copies sa_len & sa_family */
cp3 += 2;
if (cplim > cplim2)
cplim = cplim2;
while (cp2 < cplim)
*cp2++ = *cp1++ & *cp3++;
if (cp2 < cplim2)
bzero((caddr_t)cp2, (unsigned)(cplim2 - cp2));
}
/*
* Set up a routing table entry, normally
* for an interface.
*/
int
rtinit(ifa, cmd, flags)
register struct ifaddr *ifa;
int cmd, flags;
{
register struct rtentry *rt;
register struct sockaddr *dst;
register struct sockaddr *deldst;
struct mbuf *m = 0;
struct rtentry *nrt = 0;
int error;
dst = flags & RTF_HOST ? ifa->ifa_dstaddr : ifa->ifa_addr;
/*
* If it's a delete, check that if it exists, it's on the correct
* interface or we might scrub a route to another ifa which would
* be confusing at best and possibly worse.
*/
if (cmd == RTM_DELETE) {
/*
* It's a delete, so it should already exist..
* If it's a net, mask off the host bits
* (Assuming we have a mask)
*/
if ((flags & RTF_HOST) == 0 && ifa->ifa_netmask) {
m = m_get(M_WAIT, MT_SONAME);
deldst = mtod(m, struct sockaddr *);
rt_maskedcopy(dst, deldst, ifa->ifa_netmask);
dst = deldst;
}
/*
* Get an rtentry that is in the routing tree and
* contains the correct info. (if this fails, can't get there).
* We set "report" to FALSE so that if it doesn't exist,
* it doesn't report an error or clone a route, etc. etc.
*/
rt = rtalloc1(dst, 0, 0UL);
if (rt) {
/*
* Ok so we found the rtentry. it has an extra reference
* for us at this stage. we won't need that so
* lop that off now.
*/
rt->rt_refcnt--;
if (rt->rt_ifa != ifa) {
/*
* If the interface in the rtentry doesn't match
* the interface we are using, then we don't
* want to delete it, so return an error.
* This seems to be the only point of
* this whole RTM_DELETE clause.
*/
if (m)
(void) m_free(m);
return (flags & RTF_HOST ? EHOSTUNREACH
: ENETUNREACH);
}
}
/* XXX */
#if 0
else {
/*
* One would think that as we are deleting, and we know
* it doesn't exist, we could just return at this point
* with an "ELSE" clause, but apparently not..
*/
return (flags & RTF_HOST ? EHOSTUNREACH
: ENETUNREACH);
}
#endif
}
/*
* Do the actual request
*/
error = rtrequest(cmd, dst, ifa->ifa_addr, ifa->ifa_netmask,
flags | ifa->ifa_flags, &nrt);
if (m)
(void) m_free(m);
/*
* If we are deleting, and we found an entry, then
* it's been removed from the tree.. now throw it away.
*/
if (cmd == RTM_DELETE && error == 0 && (rt = nrt)) {
/*
* notify any listenning routing agents of the change
*/
rt_newaddrmsg(cmd, ifa, error, nrt);
if (rt->rt_refcnt <= 0) {
rt->rt_refcnt++; /* need a 1->0 transition to free */
rtfree(rt);
}
}
/*
* We are adding, and we have a returned routing entry.
* We need to sanity check the result.
*/
if (cmd == RTM_ADD && error == 0 && (rt = nrt)) {
/*
* We just wanted to add it.. we don't actually need a reference
*/
rt->rt_refcnt--;
/*
* If it came back with an unexpected interface, then it must
* have already existed or something. (XXX)
*/
if (rt->rt_ifa != ifa) {
printf("rtinit: wrong ifa (%p) was (%p)\n", ifa,
rt->rt_ifa);
/*
* Ask that the protocol in question
* remove anything it has associated with
* this route and ifaddr.
*/
if (rt->rt_ifa->ifa_rtrequest)
rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
/*
* Remove the referenve to the it's ifaddr.
*/
IFAFREE(rt->rt_ifa);
/*
* And substitute in references to the ifaddr
* we are adding.
*/
rt->rt_ifa = ifa;
rt->rt_ifp = ifa->ifa_ifp;
ifa->ifa_refcnt++;
/*
* Now ask the protocol to check if it needs
* any special processing in it's new form.
*/
if (ifa->ifa_rtrequest)
ifa->ifa_rtrequest(RTM_ADD, rt, SA(0));
}
/*
* notify any listenning routing agents of the change
*/
rt_newaddrmsg(cmd, ifa, error, nrt);
}
return (error);
}