/*
find the interface to use for sending a outgoing request
*/
struct nbtd_interface *nbtd_find_request_iface(struct nbtd_server *nbtd_server,
const char *address, bool allow_bcast_iface)
{
struct nbtd_interface *cur;
/* try to find a exact match */
for (cur=nbtd_server->interfaces;cur;cur=cur->next) {
if (iface_list_same_net(address, cur->ip_address, cur->netmask)) {
DEBUG(10,("find interface for dst[%s] ip: %s/%s (iface[%p])\n",
address, cur->ip_address, cur->netmask, cur));
return cur;
}
}
/* no exact match, if we have the broadcast interface, use that */
if (allow_bcast_iface && nbtd_server->bcast_interface) {
cur = nbtd_server->bcast_interface;
DEBUG(10,("find interface for dst[%s] ip: %s/%s (bcast iface[%p])\n",
address, cur->ip_address, cur->netmask, cur));
return cur;
}
/* fallback to first interface */
cur = nbtd_server->interfaces;
DEBUG(10,("find interface for dst[%s] ip: %s/%s (default iface[%p])\n",
address, cur->ip_address, cur->netmask, cur));
return cur;
}
static void nbtd_wins_randomize1Clist(struct loadparm_context *lp_ctx,
const char **addresses, struct socket_address *src)
{
const char *mask;
const char *tmp;
uint32_t num_addrs;
uint32_t idx, sidx;
int r;
for (num_addrs=0; addresses[num_addrs]; num_addrs++) { /* noop */ }
if (num_addrs <= 1) return; /* nothing to do */
/* first sort the addresses depending on the matching to the client */
LDB_TYPESAFE_QSORT(addresses, num_addrs, src, nbtd_wins_randomize1Clist_sort);
mask = lpcfg_parm_string(lp_ctx, NULL, "nbtd", "wins_randomize1Clist_mask");
if (!mask) {
mask = "255.255.255.0";
}
/*
* choose a random address to be the first in the response to the client,
* prefer the addresses inside the nbtd:wins_randomize1Clist_mask netmask
*/
r = random();
idx = sidx = r % num_addrs;
while (1) {
bool same;
/* if the current one is in the same subnet, use it */
same = iface_list_same_net(addresses[idx], src->addr, mask);
if (same) {
sidx = idx;
break;
}
/* we need to check for idx == 0, after checking for the same net */
if (idx == 0) break;
/*
* if we haven't found an address in the same subnet, search in ones
* which match the client more
*
* some notes:
*
* it's not "idx = idx % r" but "idx = r % idx"
* because in "a % b" b is the allowed range
* and b-1 is the maximum possible result, so it must be decreasing
* and the above idx == 0 check breaks the while(1) loop.
*/
idx = r % idx;
}
/* note sidx == 0 is also valid here ... */
tmp = addresses[0];
addresses[0] = addresses[sidx];
addresses[sidx] = tmp;
}
/*
return the list of interface IPs we have configured
takes an loadparm context, returns a list of IPs in string form
Does not return addresses on 127.0.0.0/8
*/
static PyObject *py_interface_ips(PyObject *self, PyObject *args)
{
PyObject *pylist;
int count;
TALLOC_CTX *tmp_ctx;
PyObject *py_lp_ctx;
struct loadparm_context *lp_ctx;
struct interface *ifaces;
int i, ifcount;
int all_interfaces = 1;
if (!PyArg_ParseTuple(args, "O|i", &py_lp_ctx, &all_interfaces))
return NULL;
tmp_ctx = talloc_new(NULL);
if (tmp_ctx == NULL) {
PyErr_NoMemory();
return NULL;
}
lp_ctx = lpcfg_from_py_object(tmp_ctx, py_lp_ctx);
if (lp_ctx == NULL) {
talloc_free(tmp_ctx);
return NULL;
}
load_interface_list(tmp_ctx, lp_ctx, &ifaces);
count = iface_list_count(ifaces);
/* first count how many are not loopback addresses */
for (ifcount = i = 0; i<count; i++) {
const char *ip = iface_list_n_ip(ifaces, i);
if (all_interfaces) {
ifcount++;
continue;
}
if (iface_list_same_net(ip, "127.0.0.1", "255.0.0.0")) {
continue;
}
if (iface_list_same_net(ip, "169.254.0.0", "255.255.0.0")) {
continue;
}
if (iface_list_same_net(ip, "::1", "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")) {
continue;
}
if (iface_list_same_net(ip, "fe80::", "ffff:ffff:ffff:ffff::")) {
continue;
}
ifcount++;
}
pylist = PyList_New(ifcount);
for (ifcount = i = 0; i<count; i++) {
const char *ip = iface_list_n_ip(ifaces, i);
if (all_interfaces) {
PyList_SetItem(pylist, ifcount, PyString_FromString(ip));
ifcount++;
continue;
}
if (iface_list_same_net(ip, "127.0.0.1", "255.0.0.0")) {
continue;
}
if (iface_list_same_net(ip, "169.254.0.0", "255.255.0.0")) {
continue;
}
if (iface_list_same_net(ip, "::1", "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")) {
continue;
}
if (iface_list_same_net(ip, "fe80::", "ffff:ffff:ffff:ffff::")) {
continue;
}
PyList_SetItem(pylist, ifcount, PyString_FromString(ip));
ifcount++;
}
talloc_free(tmp_ctx);
return pylist;
}
