📄 route.c
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* 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);
}
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.
*/
rt->rt_flags &= ~RTF_UP;
if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
rttrash++;
if (ret_nrt)
*ret_nrt = rt;
else if (rt->rt_refcnt <= 0) {
rt->rt_refcnt++;
rtfree(rt);
}
break;
#endif
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;
#ifndef __REACTOS__
case RTM_ADD:
if ((flags & RTF_GATEWAY) && !gateway)
panic("rtrequest: GATEWAY but no gateway");
if ((ifa = ifa_ifwithroute(flags, dst, gateway)) == 0)
senderr(ENETUNREACH);
#endif
makeroute:
R_Malloc(rt, struct rtentry *, sizeof(*rt));
if (rt == 0)
senderr(ENOBUFS);
Bzero(rt, sizeof(*rt));
rt->rt_flags = RTF_UP | flags;
if (rt_setgate(rt, dst, gateway)) {
Free(rt);
senderr(ENOBUFS);
}
ndst = rt_key(rt);
if (netmask) {
rt_maskedcopy(dst, ndst, netmask);
} else
Bcopy(dst, ndst, dst->sa_len);
/*
* This moved from below so that rnh->rnh_addaddr() can
* examine the ifa and ifp if it so desires.
*/
ifa->ifa_refcnt++;
rt->rt_ifa = ifa;
#ifndef __REACTOS__
rt->rt_ifp = ifa->ifa_ifp;
#endif
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) {
RTFREE(rt2);
}
}
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 (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++;
}
}
#ifndef __REACTOS__
if (ifa->ifa_rtrequest)
ifa->ifa_rtrequest(req, rt, SA(ret_nrt ? *ret_nrt : 0));
#endif
/*
* 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)) {
struct rtfc_arg arg;
arg.rnh = rnh;
arg.rt0 = rt;
rnh->rnh_walktree_from(rnh, rt_key(rt), rt_mask(rt),
rt_fixchange, &arg);
}
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.
*/
#ifndef __REACTOS__
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;
}
#endif
/*
* 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];
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 1;
rt->rt_nodes->rn_key = new;
} else {
new = rt->rt_nodes->rn_key;
old = 0;
}
Bcopy(gate, (rt->rt_gateway = (struct sockaddr *)(new + dlen)), glen);
if (old) {
Bcopy(dst, new, dlen);
Free(old);
}
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 obviuosly 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 1; /* 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;
}
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;
{
int error = EADDRNOTAVAIL;
#ifndef __REACTOS__
register struct rtentry *rt;
register struct sockaddr *dst;
register struct sockaddr *deldst;
struct mbuf *m = 0;
struct rtentry *nrt = 0;
dst = flags & RTF_HOST ? ifa->ifa_dstaddr : ifa->ifa_addr;
if (cmd == RTM_DELETE) {
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;
}
rt = rtalloc1(dst, 0, 0UL);
if (rt) {
rt->rt_refcnt--;
if (rt->rt_ifa != ifa) {
if (m)
(void) m_free(m);
return (flags & RTF_HOST ? EHOSTUNREACH
: ENETUNREACH);
}
}
}
error = rtrequest(cmd, dst, ifa->ifa_addr, ifa->ifa_netmask,
flags | ifa->ifa_flags, &nrt);
if (m)
(void) m_free(m);
if (cmd == RTM_DELETE && error == 0 && (rt = nrt)) {
rt_newaddrmsg(cmd, ifa, error, nrt);
if (rt->rt_refcnt <= 0) {
rt->rt_refcnt++;
rtfree(rt);
}
}
if (cmd == RTM_ADD && error == 0 && (rt = nrt)) {
rt->rt_refcnt--;
if (rt->rt_ifa != ifa) {
printf("rtinit: wrong ifa (%p) was (%p)\n", ifa,
rt->rt_ifa);
if (rt->rt_ifa->ifa_rtrequest)
rt->rt_ifa->ifa_rtrequest(RTM_DELETE, rt, SA(0));
IFAFREE(rt->rt_ifa);
rt->rt_ifa = ifa;
rt->rt_ifp = ifa->ifa_ifp;
ifa->ifa_refcnt++;
if (ifa->ifa_rtrequest)
ifa->ifa_rtrequest(RTM_ADD, rt, SA(0));
}
rt_newaddrmsg(cmd, ifa, error, nrt);
}
#endif
return (error);
}
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