gprs: Refactor gbprox_register_tlli()
Currently gbprox_register_tlli() is a rather complex function.
This patch splits it into several smaller functions to ease reviewing
and maintaining it.
Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gb_proxy.c b/openbsc/src/gprs/gb_proxy.c
index c6d028f..500968b 100644
--- a/openbsc/src/gprs/gb_proxy.c
+++ b/openbsc/src/gprs/gb_proxy.c
@@ -495,6 +495,16 @@
return 1;
}
+static void gbprox_attach_tlli_info(struct gbproxy_peer *peer, time_t now,
+ struct gbproxy_tlli_info *tlli_info)
+{
+ struct gbproxy_patch_state *state = &peer->patch_state;
+
+ tlli_info->timestamp = now;
+ llist_add(&tlli_info->list, &state->enabled_tllis);
+ state->enabled_tllis_count += 1;
+}
+
int gbprox_remove_stale_tllis(struct gbproxy_peer *peer, time_t now)
{
struct gbproxy_patch_state *state = &peer->patch_state;
@@ -530,6 +540,35 @@
return deleted_count;
}
+static struct gbproxy_tlli_info *gbprox_get_detached_tlli_info(
+ struct gbproxy_peer *peer,
+ struct gbproxy_tlli_info *tlli_info,
+ uint32_t tlli)
+{
+ struct gbproxy_patch_state *state = &peer->patch_state;
+
+ if (!tlli_info) {
+ tlli_info = talloc_zero(peer, struct gbproxy_tlli_info);
+ tlli_info->tlli = tlli;
+ } else {
+ llist_del(&tlli_info->list);
+ OSMO_ASSERT(state->enabled_tllis_count > 0);
+ state->enabled_tllis_count -= 1;
+ }
+
+ return tlli_info;
+}
+
+static void gbprox_update_tlli_info(struct gbproxy_tlli_info *tlli_info,
+ const uint8_t *imsi, size_t imsi_len)
+{
+ tlli_info->mi_data_len = imsi_len;
+ tlli_info->mi_data =
+ talloc_realloc_size(tlli_info, tlli_info->mi_data, imsi_len);
+ OSMO_ASSERT(tlli_info->mi_data != NULL);
+ memcpy(tlli_info->mi_data, imsi, imsi_len);
+}
+
void gbprox_register_tlli(struct gbproxy_peer *peer, uint32_t tlli,
const uint8_t *imsi, size_t imsi_len)
{
@@ -537,6 +576,7 @@
struct gbproxy_tlli_info *tlli_info;
int enable_patching;
time_t now = 0;
+ int tlli_already_known;
if (gprs_tlli_type(tlli) != TLLI_LOCAL)
return;
@@ -547,14 +587,14 @@
if (!peer->cfg->check_imsi)
return;
- tlli_info = gbprox_find_tlli(peer, tlli);
-
/* Check, whether the IMSI matches */
enable_patching = gbprox_check_imsi(peer, imsi, imsi_len);
if (enable_patching < 0)
return;
+ tlli_info = gbprox_find_tlli(peer, tlli);
+
if (!tlli_info) {
tlli_info = gbprox_find_tlli_by_mi(peer, imsi, imsi_len);
@@ -567,37 +607,27 @@
}
}
- if (!tlli_info) {
- if (!enable_patching)
- return;
+ tlli_already_known = tlli_info != NULL;
- LOGP(DGPRS, LOGL_INFO, "Adding TLLI %08x to list\n", tlli);
- tlli_info = talloc_zero(peer, struct gbproxy_tlli_info);
- tlli_info->tlli = tlli;
- } else {
- llist_del(&tlli_info->list);
- OSMO_ASSERT(state->enabled_tllis_count > 0);
- state->enabled_tllis_count -= 1;
- }
+ if (!tlli_already_known && !enable_patching)
+ return;
+ tlli_info = gbprox_get_detached_tlli_info(peer, tlli_info, tlli);
OSMO_ASSERT(tlli_info != NULL);
if (enable_patching) {
+ if (!tlli_already_known)
+ LOGP(DGPRS, LOGL_INFO, "Adding TLLI %08x to list\n", tlli);
+
now = time(NULL);
- tlli_info->timestamp = now;
- llist_add(&tlli_info->list, &state->enabled_tllis);
- state->enabled_tllis_count += 1;
+ gbprox_attach_tlli_info(peer, now, tlli_info);
+ gbprox_update_tlli_info(tlli_info, imsi, imsi_len);
gbprox_remove_stale_tllis(peer, now);
-
- if (tlli_info != llist_entry(state->enabled_tllis.next,
- struct gbproxy_tlli_info, list)) {
- LOGP(DGPRS, LOGL_ERROR,
- "Unexpectedly removed new TLLI entry as stale, "
- "TLLI %08x\n", tlli);
- tlli_info = NULL;
- }
+ /* Be on the safe side, currently the new tlli_info won't be
+ * removed, but this not enforced explicitely */
+ tlli_info = NULL;
} else {
LOGP(DGPRS, LOGL_INFO,
"Removing TLLI %08x from list (patching no longer enabled)\n",
@@ -606,14 +636,6 @@
tlli_info = NULL;
}
- if (tlli_info) {
- tlli_info->mi_data_len = imsi_len;
- tlli_info->mi_data =
- talloc_realloc_size(tlli_info, tlli_info->mi_data, imsi_len);
- OSMO_ASSERT(tlli_info->mi_data != NULL);
- memcpy(tlli_info->mi_data, imsi, imsi_len);
- }
-
peer->ctrg->ctr[GBPROX_PEER_CTR_TLLI_CACHE_SIZE].current =
state->enabled_tllis_count;
}