cosmetic prep: publish vlr_use_umts_aka() decision
During Set Ciphering Mode on GERAN, it is required to know whether UMTS AKA is
used to decide which Kc to pick. Change static function is_umts_auth() into
public vlr_use_umts_aka(), so future patches can re-use it.
Prepares: If04e405426c55a81341747a9b450a69188525d5c
Change-Id: I85d784c62ecbabdb6186a3dae4dcd554e7921041
diff --git a/src/libvlr/vlr.c b/src/libvlr/vlr.c
index 16f365e..55b8de0 100644
--- a/src/libvlr/vlr.c
+++ b/src/libvlr/vlr.c
@@ -1122,6 +1122,23 @@
}
}
+/* Decide whether UMTS AKA should be used.
+ * UTRAN networks are by definition R99 capable, and the auth vector is required to contain UMTS AKA
+ * tokens. This is expected to be verified by the caller. On GERAN, UMTS AKA must be used iff MS and
+ * GERAN are R99 capable and UMTS AKA tokens are available.
+ * \param[in] vec Auth tokens (received from the HLR).
+ * \param[in] is_r99 True when BTS and GERAN are R99 capable.
+ * \returns true to use UMTS AKA, false to use pre-R99 GSM AKA.
+ */
+bool vlr_use_umts_aka(struct osmo_auth_vector *vec, bool is_r99)
+{
+ if (!is_r99)
+ return false;
+ if (!(vec->auth_types & OSMO_AUTH_TYPE_UMTS))
+ return false;
+ return true;
+}
+
void log_set_filter_vlr_subscr(struct log_target *target,
struct vlr_subscr *vlr_subscr)
{