nat: Move paging by lac handling code into the utils file
Moving it here means we can more easily test this code, there is one
behaviour change with the code that we only support paging messages
with one LAC and will silently ignore the others.
diff --git a/openbsc/src/nat/bsc_nat.c b/openbsc/src/nat/bsc_nat.c
index cafca83..52b3f01 100644
--- a/openbsc/src/nat/bsc_nat.c
+++ b/openbsc/src/nat/bsc_nat.c
@@ -227,34 +227,11 @@
* message and then send it to the authenticated messages...
*/
if (parsed->ipa_proto == IPAC_PROTO_SCCP && parsed->gsm_type == BSS_MAP_MSG_PAGING) {
- int data_length;
- const u_int8_t *data;
- struct tlv_parsed tp;
- int i = 0;
-
- tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 3, msgb_l3len(msg) - 3, 0, 0);
- if (!TLVP_PRESENT(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST)) {
- LOGP(DNAT, LOGL_ERROR, "No CellIdentifier List inside paging msg.\n");
- goto exit;
- }
-
- data_length = TLVP_LEN(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST);
- data = TLVP_VAL(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST);
- if (data[0] != CELL_IDENT_LAC) {
- LOGP(DNAT, LOGL_ERROR, "Unhandled cell ident discrminator: %c\n", data[0]);
- goto exit;
- }
-
- /* go through each LAC and forward the message */
- for (i = 1; i < data_length - 1; i += 2) {
- unsigned int _lac = ntohs(*(unsigned int *) &data[i]);
- llist_for_each_entry(bsc, &nat->bsc_connections, list_entry) {
- if (!bsc->authenticated || _lac != bsc->lac)
- continue;
-
- bsc_write(bsc, msg->data, msg->len);
- }
- }
+ bsc = bsc_nat_find_bsc(nat, msg);
+ if (bsc)
+ bsc_write(bsc, msg->data, msg->len);
+ else
+ LOGP(DNAT, LOGL_ERROR, "Could not determine BSC for paging.\n");
goto exit;
}