/*
* find the local address 'closest' to the remote system, copy it to
* local and return the ifc for that address
*/
void
findlocalip(Fs *f, uint8_t *local, uint8_t *remote)
{
int version, atype = unspecifiedv6, atypel = unknownv6;
int atyper, deprecated;
uint8_t gate[IPaddrlen], gnet[IPaddrlen];
Ipifc *ifc;
Iplifc *lifc;
Route *r;
USED(atype);
USED(atypel);
qlock(f->ipifc);
r = v6lookup(f, remote, nil);
version = (memcmp(remote, v4prefix, IPv4off) == 0)? V4: V6;
if(r != nil){
ifc = r->ifc;
if(r->type & Rv4)
v4tov6(gate, r->v4.gate);
else {
ipmove(gate, r->v6.gate);
ipmove(local, v6Unspecified);
}
switch(version) {
case V4:
/* find ifc address closest to the gateway to use */
for(lifc = ifc->lifc; lifc; lifc = lifc->next){
maskip(gate, lifc->mask, gnet);
if(ipcmp(gnet, lifc->net) == 0){
ipmove(local, lifc->local);
goto out;
}
}
break;
case V6:
/* find ifc address with scope matching the destination */
atyper = v6addrtype(remote);
deprecated = 0;
for(lifc = ifc->lifc; lifc; lifc = lifc->next){
atypel = v6addrtype(lifc->local);
/* prefer appropriate scope */
if(atypel > atype && atype < atyper ||
atypel < atype && atype > atyper){
ipmove(local, lifc->local);
deprecated = !v6addrcurr(lifc);
atype = atypel;
} else if(atypel == atype){
/* avoid deprecated addresses */
if(deprecated && v6addrcurr(lifc)){
ipmove(local, lifc->local);
atype = atypel;
deprecated = 0;
}
}
if(atype == atyper && !deprecated)
goto out;
}
if(atype >= atyper)
goto out;
break;
default:
panic("findlocalip: version %d", version);
}
}
switch(version){
case V4:
findprimaryipv4(f, local);
break;
case V6:
findprimaryipv6(f, local);
break;
default:
panic("findlocalip2: version %d", version);
}
out:
qunlock(f->ipifc);
}
/*
* find the local address 'closest' to the remote system, copy it to
* local and return the ifc for that address
*/
void findlocalip(struct Fs *f, uint8_t * local, uint8_t * remote)
{
struct Ipifc *ifc;
struct Iplifc *lifc;
struct route *r;
uint8_t gate[IPaddrlen];
uint8_t gnet[IPaddrlen];
int version;
int atype = unspecifiedv6, atypel = unknownv6;
qlock(&f->ipifc->qlock);
r = v6lookup(f, remote, NULL);
version = isv4(remote) ? V4 : V6;
if (r != NULL) {
ifc = r->rt.ifc;
if (r->rt.type & Rv4)
v4tov6(gate, r->v4.gate);
else {
ipmove(gate, r->v6.gate);
ipmove(local, v6Unspecified);
}
/* find ifc address closest to the gateway to use */
switch (version) {
case V4:
for (lifc = ifc->lifc; lifc; lifc = lifc->next) {
maskip(gate, lifc->mask, gnet);
if (ipcmp(gnet, lifc->net) == 0) {
ipmove(local, lifc->local);
goto out;
}
}
break;
case V6:
for (lifc = ifc->lifc; lifc; lifc = lifc->next) {
atypel = v6addrtype(lifc->local);
maskip(gate, lifc->mask, gnet);
if (ipcmp(gnet, lifc->net) == 0)
if (atypel > atype)
if (v6addrcurr(lifc)) {
ipmove(local, lifc->local);
atype = atypel;
if (atype == globalv6)
break;
}
}
if (atype > unspecifiedv6)
goto out;
break;
default:
panic("findlocalip: version %d", version);
}
}
switch (version) {
case V4:
findprimaryipv4(f, local);
break;
case V6:
findprimaryipv6(f, local);
break;
default:
panic("findlocalip2: version %d", version);
}
out:
qunlock(&f->ipifc->qlock);
}