GPRS: Modularize the NS implementation

* move UDP listener code for NSIP from input/ipaccess.c and into gprs_ns.c
* add PDU type, IE and CAUSE values for later IP based 3GPP TS 48.016
* support multiple NS-VCs and their lookup based on NSVC and sockaddr_in
* maintain the remote_state (blocked/alive) for each NSVC
* introduce the concept of GPRS_NS instances, move all global vars to instance
* remove hardcoded calls to gprs_bssgp_rcvmsg() and replace it by callback

WARNING: This is not finished code.  While it will compile, it will not work
yet, as BSSGP needs to be converted to properly indicate the NSVC to which it
needs to send data.

1 files changed, 53 insertions, 9 deletions

diff --git a/openbsc/include/openbsc/gprs_ns.h b/openbsc/include/openbsc/gprs_ns.h
index 9ea4d675..98b31f8d 100644
--- a/openbsc/include/openbsc/gprs_ns.h
+++ b/openbsc/include/openbsc/gprs_ns.h
@@ -1,6 +1,10 @@
 #ifndef _GPRS_NS_H
 #define _GPRS_NS_H
 
+/* GPRS Networks Service (NS) messages on the Gb interface
+ * 3GPP TS 08.16 version 8.0.1 Release 1999 / ETSI TS 101 299 V8.0.1 (2002-05)
+ * 3GPP TS 48.016 version 6.5.0 Release 6 / ETSI TS 148 016 V6.5.0 (2005-11) */
+
 struct gprs_ns_hdr {
 	u_int8_t pdu_type;
 	u_int8_t data[0];
@@ -18,6 +22,15 @@ enum ns_pdu_type {
 	NS_PDUT_STATUS		= 0x08,
 	NS_PDUT_ALIVE		= 0x0a,
 	NS_PDUT_ALIVE_ACK	= 0x0b,
+	/* TS 48.016 Section 10.3.7, Table 10.3.7.1 */
+	SNS_PDUT_ACK		= 0x0c,
+	SNS_PDUT_ADD		= 0x0d,
+	SNS_PDUT_CHANGE_WEIGHT	= 0x0e,
+	SNS_PDUT_CONFIG		= 0x0f,
+	SNS_PDUT_CONFIG_ACK	= 0x10,
+	SNS_PDUT_DELETE		= 0x11,
+	SNS_PDUT_SIZE		= 0x12,
+	SNS_PDUT_SIZE_ACK	= 0x13,
 };
 
 /* TS 08.16, Section 10.3, Table 12 */
@@ -27,6 +40,14 @@ enum ns_ctrl_ie {
 	NS_IE_PDU		= 0x02,
 	NS_IE_BVCI		= 0x03,
 	NS_IE_NSEI		= 0x04,
+	/* TS 48.016 Section 10.3, Table 10.3.1 */
+	NS_IE_IPv4_LIST		= 0x05,
+	NS_IE_IPv6_LIST		= 0x06,
+	NS_IE_MAX_NR_NSVC	= 0x07,
+	NS_IE_IPv4_EP_NR	= 0x08,
+	NS_IE_IPv6_EP_NR	= 0x09,
+	NS_IE_RESET_FLAG	= 0x0a,
+	NS_IE_IP_ADDR		= 0x0b,
 };
 
 /* TS 08.16, Section 10.3.2, Table 13 */
@@ -42,20 +63,43 @@ enum ns_cause {
 	NS_CAUSE_PROTO_ERR_UNSPEC	= 0x0b,
 	NS_CAUSE_INVAL_ESSENT_IE	= 0x0c,
 	NS_CAUSE_MISSING_ESSENT_IE	= 0x0d,
+	/* TS 48.016 Section 10.3.2, Table 10.3.2.1 */
+	NS_CAUSE_INVAL_NR_IPv4_EP	= 0x0e,
+	NS_CAUSE_INVAL_NR_IPv6_EP	= 0x0f,
+	NS_CAUSE_INVAL_NR_NS_VC		= 0x10,
+	NS_CAUSE_INVAL_WEIGH		= 0x11,
+	NS_CAUSE_UNKN_IP_EP		= 0x12,
+	NS_CAUSE_UNKN_IP_ADDR		= 0x13,
+	NS_CAUSE_UNKN_IP_TEST_FAILED	= 0x14,
 };
 
-/* a layer 1 entity transporting NS frames */
-struct gprs_ns_link {
-	union {
-		struct {
-			int fd;
-		} ip;
-	};
+struct gprs_nsvc;
+struct gprs_ns_inst;
+
+enum gprs_ns_evt {
+	GPRS_NS_EVT_UNIT_DATA,
 };
 
+typedef int gprs_ns_cb_t(enum gprs_ns_evt event, struct gprs_nsvc *nsvc,
+			 struct msgb *msg, u_int16_t bvci);
+
+/* Create a new NS protocol instance */
+struct gprs_ns_inst *gprs_ns_instantiate(gprs_ns_cb_t *cb);
+
+/* Destroy a NS protocol instance */
+void gprs_ns_destroy(struct gprs_ns_inst *nsi);
 
-int gprs_ns_rcvmsg(struct msgb *msg, struct sockaddr_in *saddr);
+/* Listen for incoming GPRS packets */
+int nsip_listen(struct gprs_ns_inst *nsi, uint16_t udp_port);
 
-int gprs_ns_sendmsg(struct gprs_ns_link *link, u_int16_t bvci,
+struct sockaddr_in;
+
+/* main entry point, here incoming NS frames enter */
+int gprs_ns_rcvmsg(struct gprs_ns_inst *nsi, struct msgb *msg,
+		   struct sockaddr_in *saddr);
+
+/* main function for higher layers (BSSGP) to send NS messages */
+int gprs_ns_sendmsg(struct gprs_nsvc *nsvc, u_int16_t bvci,
 		    struct msgb *msg);
+
 #endif