gtphub: make sure mapped TEIs aren't occupied (incomplete).
This could be done way better, discussion is pending/ongoing. It is indeed
quite unlikely that any user will ever hit this situation, so there is no
strong drive to invest effort in a more comprehensive implementation.
Sponsored-by: On-Waves ehi
diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c
index 5807f5f..6037d3b 100644
--- a/openbsc/src/gprs/gtphub.c
+++ b/openbsc/src/gprs/gtphub.c
@@ -1210,43 +1210,99 @@
return NULL;
}
-static void gtphub_expire_reused_tei(struct gtphub *hub,
- int side_idx,
- int plane_idx,
- struct gtphub_peer_port *from,
- uint32_t tei_orig,
- struct gtphub_tunnel *except)
+static int gtphub_check_mapped_tei(struct gtphub_tunnel_endpoint *new_te,
+ struct gtphub_tunnel_endpoint *iterated_te,
+ uint32_t *tei_min,
+ uint32_t *tei_max)
{
- struct gtphub_tunnel *exists, *e2;
+ if (new_te->tei_repl != iterated_te->tei_repl)
+ return 1;
- llist_for_each_entry_safe(exists, e2, &hub->tunnels, entry) {
- if (exists == except)
+ /* new_te->tei_repl is already taken. Try to find one out of the known
+ * range. */
+
+ if ((*tei_max) < 0xffffffff) {
+ (*tei_max)++;
+ new_te->tei_repl = *tei_max;
+ return 1;
+ } else if ((*tei_min) > 1) {
+ (*tei_min)--;
+ new_te->tei_repl = *tei_min;
+ return 1;
+ }
+
+ /* None seems to be available. */
+ return 0;
+}
+
+static int gtphub_check_reused_teis(struct gtphub *hub,
+ struct gtphub_tunnel *new_tun)
+{
+ uint32_t tei_min = 0xffffffff;
+ uint32_t tei_max = 0;
+ int side_idx;
+ int plane_idx;
+ int side_idx2;
+ int plane_idx2;
+ struct gtphub_tunnel_endpoint *te;
+ struct gtphub_tunnel_endpoint *te2;
+
+ struct gtphub_tunnel *tun, *ntun;
+
+ llist_for_each_entry_safe(tun, ntun, &hub->tunnels, entry) {
+ if (tun == new_tun)
continue;
- struct gtphub_tunnel_endpoint *te =
- &exists->endpoint[side_idx][plane_idx];
- if ((te->tei_orig == tei_orig)
- && gsn_addr_same(&te->peer->peer_addr->addr,
- &from->peer_addr->addr)) {
+ /* Check whether the GSN sent a TEI that it is reusing from a
+ * previous tunnel. */
+ for_each_side_and_plane(side_idx, plane_idx) {
+ te = &tun->endpoint[side_idx][plane_idx];
+ te2 = &new_tun->endpoint[side_idx][plane_idx];
+ if ((te->tei_orig == te2->tei_orig)
+ && gsn_addr_same(&te->peer->peer_addr->addr,
+ &te2->peer->peer_addr->addr)) {
- /* The peer is reusing a TEI that I believe to
- * be part of another tunnel. The other tunnel
- * must be stale, then. */
- LOG(LOGL_NOTICE,
- "Expiring tunnel due to reused TEI:"
- " peer %s sent %s TEI %x,"
- " previously used by tunnel %s...\n",
- gtphub_port_str(from),
- gtphub_plane_idx_names[plane_idx],
- tei_orig,
- gtphub_tunnel_str(exists));
- LOG(LOGL_NOTICE, "...while establishing tunnel %s\n",
- gtphub_tunnel_str(except));
- expiring_item_del(&exists->expiry_entry);
- /* continue to find more matches. There shouldn't be
- * any, but let's make sure. */
+ /* The peer is reusing a TEI that I believe to
+ * be part of another tunnel. The other tunnel
+ * must be stale, then. */
+ LOG(LOGL_NOTICE,
+ "Expiring tunnel due to reused TEI:"
+ " peer %s sent %s TEI %x,"
+ " previously used by tunnel %s...\n",
+ gtphub_port_str(te->peer),
+ gtphub_plane_idx_names[plane_idx],
+ te->tei_orig,
+ gtphub_tunnel_str(tun));
+ LOG(LOGL_NOTICE, "...while establishing tunnel %s\n",
+ gtphub_tunnel_str(new_tun));
+ expiring_item_del(&tun->expiry_entry);
+ /* continue to find more matches. There shouldn't be
+ * any, but let's make sure. */
+ }
}
+
+ /* Check whether the mapped TEIs assigned to the endpoints are
+ * used anywhere else. */
+ for_each_side_and_plane(side_idx, plane_idx) {
+ te = &tun->endpoint[side_idx][plane_idx];
+ tei_min = (tei_min < te->tei_repl)? tei_min : te->tei_repl;
+ tei_max = (tei_max > te->tei_repl)? tei_max : te->tei_repl;
+
+ for_each_side_and_plane(side_idx2, plane_idx2) {
+ te2 = &new_tun->endpoint[side_idx2][plane_idx2];
+ if (!gtphub_check_mapped_tei(te2, te, &tei_min, &tei_max)) {
+ LOG(LOGL_ERROR,
+ "No mapped TEI is readily available."
+ " Searching for holes between occupied"
+ " TEIs not implemented.");
+ return 0;
+ }
+ }
+ }
+
}
+
+ return 1;
}
static void gtphub_tunnel_refresh(struct gtphub *hub,
@@ -1455,9 +1511,8 @@
tun->endpoint[side_idx][plane_idx].tei_repl = mapped_tei;
p->ie[ie_idx]->tv4.v = hton32(mapped_tei);
- gtphub_expire_reused_tei(hub, side_idx, plane_idx,
- peer_from_ie, tei_from_ie,
- tun);
+ if (!gtphub_check_reused_teis(hub, tun))
+ return -1;
}
/* Replace the GSN address to reflect gtphub. */