GPRS: Introduce a GPRS Gb Proxy

The ida of the Gb proxy is to aggregate Gb links with a number of BSS
and then present all the BSSGP-VC's together inside one NS-VC to the
actual SGSN.

The code is not yet expected to be complete.

2 files changed, 48 insertions, 1 deletions

diff --git a/openbsc/include/openbsc/gprs_bssgp.h b/openbsc/include/openbsc/gprs_bssgp.h
index f85ac48e..3040e6a0 100644
--- a/openbsc/include/openbsc/gprs_bssgp.h
+++ b/openbsc/include/openbsc/gprs_bssgp.h
@@ -133,6 +133,16 @@ enum gprs_bssgp_cause {
 	BSSGP_CAUSE_PDU_INCOMP_FEAT	= 0x28,
 };
 
+/* Our implementation */
+
+#include <osmocore/tlv.h>
+
 extern int gprs_bssgp_rcvmsg(struct msgb *msg, u_int16_t bvci);
 
+/* Wrapper around TLV parser to parse BSSGP IEs */
+static inline int bssgp_tlv_parse(struct tlv_parsed *tp, u_int8_t *buf, int len)
+{
+	return tlv_parse(tp, &tvlv_att_def, buf, len, 0, 0);
+}
+
 #endif /* _GPRS_BSSGP_H */
diff --git a/openbsc/include/openbsc/gprs_ns.h b/openbsc/include/openbsc/gprs_ns.h
index 34a3e581..dd10d333 100644
--- a/openbsc/include/openbsc/gprs_ns.h
+++ b/openbsc/include/openbsc/gprs_ns.h
@@ -73,7 +73,37 @@ enum ns_cause {
 	NS_CAUSE_UNKN_IP_TEST_FAILED	= 0x14,
 };
 
-struct gprs_nsvc;
+
+/* Our Implementation */
+#include <netinet/in.h>
+
+#define NSE_S_BLOCKED	0x0001
+#define NSE_S_ALIVE	0x0002
+
+struct gprs_nsvc {
+	struct llist_head list;
+	struct gprs_ns_inst *nsi;
+
+	u_int16_t nsei;		/* end-to-end significance */
+	u_int16_t nsvci;	/* uniquely identifies NS-VC at SGSN */
+
+	u_int32_t state;
+	u_int32_t remote_state;
+
+	struct timer_list alive_timer;
+	int timer_is_tns_alive;
+	int alive_retries;
+
+	int remote_end_is_sgsn;
+
+	union {
+		struct {
+			struct sockaddr_in bts_addr;
+		} ip;
+	};
+};
+
+
 struct gprs_ns_inst;
 
 enum gprs_ns_evt {
@@ -101,4 +131,11 @@ int gprs_ns_rcvmsg(struct gprs_ns_inst *nsi, struct msgb *msg,
 /* main function for higher layers (BSSGP) to send NS messages */
 int gprs_ns_sendmsg(struct gprs_ns_inst *nsi, struct msgb *msg);
 
+
+/* Listen for incoming GPRS packets */
+int nsip_listen(struct gprs_ns_inst *nsi, uint16_t udp_port);
+
+/* Establish a connection (from the BSS) to the SGSN */
+struct gprs_nsvc *nsip_connect(struct gprs_ns_inst *nsi,
+				struct sockaddr_in *dest, uint16_t nsvci);
 #endif