[GPRS] Initial untested support for libgtp
libgtp of the OpenGGSN project will allow us to speak the GTPv0/v1
protocol of the interface between SGSN and GGSN.
This commit includes code for the main libgtp integration (file
descriptor, select loop, timer) as well as code to encode/send
a CREATE PDP CONTEXT request.
diff --git a/openbsc/src/gprs/gprs_gmm.c b/openbsc/src/gprs/gprs_gmm.c
index 4a42113..fc9d007 100644
--- a/openbsc/src/gprs/gprs_gmm.c
+++ b/openbsc/src/gprs/gprs_gmm.c
@@ -48,8 +48,10 @@
#include <openbsc/gprs_llc.h>
#include <openbsc/gprs_sgsn.h>
+/* Protocol related stuff, should go into libosmocore */
+
/* 10.5.5.14 GPRS MM Cause / Table 10.5.147 */
-struct value_string gmm_cause_names[] = {
+const struct value_string gmm_cause_names[] = {
/* FIXME */
{ GMM_CAUSE_SEM_INCORR_MSG, "Semantically incorrect message" },
{ GMM_CAUSE_INV_MAND_INFO, "Invalid mandatory information" },
@@ -67,7 +69,7 @@
};
/* 10.5.6.6 SM Cause / Table 10.5.157 */
-struct value_string gsm_cause_names[] = {
+const struct value_string gsm_cause_names[] = {
{ GSM_CAUSE_INSUFF_RSRC, "Insufficient resources" },
{ GSM_CAUSE_MISSING_APN, "Missing or unknown APN" },
{ GSM_CAUSE_UNKNOWN_PDP, "Unknown PDP address or PDP type" },
@@ -101,34 +103,31 @@
{ 0, NULL }
};
-static const char *att_name(uint8_t type)
-{
- switch (type) {
- case GPRS_ATT_T_ATTACH:
- return "GPRS attach";
- case GPRS_ATT_T_ATT_WHILE_IMSI:
- return "GPRS attach while IMSI attached";
- case GPRS_ATT_T_COMBINED:
- return "Combined GPRS/IMSI attach";
- default:
- return "unknown";
- }
-}
+/* 10.5.5.2 */
+const struct value_string gprs_att_t_strs[] = {
+ { GPRS_ATT_T_ATTACH, "GPRS attach" },
+ { GPRS_ATT_T_ATT_WHILE_IMSI, "GPRS attach while IMSI attached" },
+ { GPRS_ATT_T_COMBINED, "Combined GPRS/IMSI attach" },
+ { 0, NULL }
+};
-static const char *upd_name(uint8_t type)
-{
- switch (type) {
- case GPRS_UPD_T_RA:
- return "RA updating";
- case GPRS_UPD_T_RA_LA:
- return "combined RA/LA updating";
- case GPRS_UPD_T_RA_LA_IMSI_ATT:
- return "combined RA/LA updating + IMSI attach";
- case GPRS_UPD_T_PERIODIC:
- return "periodic updating";
- }
- return "unknown";
-}
+const struct value_string gprs_upd_t_strs[] = {
+ { GPRS_UPD_T_RA, "RA updating" },
+ { GPRS_UPD_T_RA_LA, "combined RA/LA updating" },
+ { GPRS_UPD_T_RA_LA_IMSI_ATT, "combined RA/LA updating + IMSI attach" },
+ { GPRS_UPD_T_PERIODIC, "periodic updating" },
+ { 0, NULL }
+};
+
+/* 10.5.5.5 */
+const struct value_string gprs_det_t_mo_strs[] = {
+ { GPRS_DET_T_MO_GPRS, "GPRS detach" },
+ { GPRS_DET_T_MO_IMSI, "IMSI detach" },
+ { GPRS_DET_T_MO_COMBINED, "Combined GPRS/IMSI detach" },
+ { 0, NULL }
+};
+
+/* Our implementation, should be kept in SGSN */
/* Send a message through the underlying layer */
static int gsm48_gmm_sendmsg(struct msgb *msg, int command)
@@ -215,6 +214,22 @@
return gsm48_gmm_sendmsg(msg, 0);
}
+/* Chapter 9.4.6.2 Detach accept */
+static gsm48_tx_gmm_det_ack(struct msgb *old_msg, uint8_t force_stby)
+{
+ struct msgb *msg = gsm48_msgb_alloc();
+ struct gsm48_hdr *gh;
+
+ DEBUGP(DMM, "<- GPRS DETACH ACCEPT\n");
+
+ gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
+ gh->proto_discr = GSM48_PDISC_MM_GPRS;
+ gh->msg_type = GSM48_MT_GMM_DETACH_ACK;
+ gh->data[0] = force_stby;
+
+ return gsm48_gmm_sendmsg(msg, 0);
+}
+
/* Transmit Chapter 9.4.12 Identity Request */
static int gsm48_tx_gmm_id_req(struct msgb *old_msg, uint8_t id_type)
{
@@ -260,7 +275,7 @@
struct sgsn_mm_ctx *ctx;
gsm48_mi_to_string(mi_string, sizeof(mi_string), &gh->data[1], gh->data[0]);
- DEBUGP(DMM, "GMM IDENTITY RESPONSE: mi_type=0x%02x MI(%s) ",
+ DEBUGP(DMM, "-> GMM IDENTITY RESPONSE: mi_type=0x%02x MI(%s) ",
mi_type, mi_string);
bssgp_parse_cell_id(&ra_id, msgb_bcid(msg));
@@ -320,7 +335,7 @@
uint16_t cid;
struct sgsn_mm_ctx *ctx;
- DEBUGP(DMM, "GMM ATTACH REQUEST ");
+ DEBUGP(DMM, "-> GMM ATTACH REQUEST ");
/* As per TS 04.08 Chapter 4.7.1.4, the attach request arrives either
* with a foreign TLLI (P-TMSI that was allocated to the MS before),
@@ -352,7 +367,8 @@
gsm48_mi_to_string(mi_string, sizeof(mi_string), mi, mi_len);
- DEBUGPC(DMM, "MI(%s) type=\"%s\" ", mi_string, att_name(att_type));
+ DEBUGPC(DMM, "MI(%s) type=\"%s\" ", mi_string,
+ get_value_string(gprs_att_t_strs, att_type));
/* Old routing area identification 10.5.5.15 */
old_ra_info = cur;
@@ -411,6 +427,38 @@
return gsm48_tx_gmm_att_rej(msg, GMM_CAUSE_SEM_INCORR_MSG);
}
+/* Section 4.7.4.1 / 9.4.5.2 MO Detach request */
+static int gsm48_rx_gmm_det_req(struct msgb *msg)
+{
+ struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
+ struct sgsn_mm_ctx *ctx;
+ uint8_t detach_type, power_off;
+ struct gprs_ra_id ra_id;
+
+ bssgp_parse_cell_id(&ra_id, msgb_bcid(msg));
+ ctx = sgsn_mm_ctx_by_tlli(msgb_tlli(msg), &ra_id);
+ if (!ctx) {
+ LOGP(DMM, LOGL_NOTICE, "-> GMM DETACH REQUEST for unknown "
+ "TLLI=0x%08x\n", msgb_tlli(msg));
+ /* FIXME: send detach reject */
+ }
+
+ detach_type = gh->data[0] & 0x7;
+ power_off = gh->data[0] & 0x8;
+
+ /* FIXME: In 24.008 there is an optional P-TMSI and P-TMSI signature IE */
+
+ DEBUGP(DMM, "-> GMM DETACH REQUEST TLLI=0x%08x type=%s %s\n",
+ msgb_tlli(msg), get_value_string(gprs_det_t_mo_strs, detach_type),
+ power_off ? "Power-off" : "");
+
+ /* Mark MM state as deregistered */
+ ctx->mm_state = GMM_DEREGISTERED;
+
+ /* force_stby = 0 */
+ return gsm48_tx_gmm_det_ack(msg, 0);
+}
+
/* Chapter 9.4.15: Routing area update accept */
static int gsm48_tx_gmm_ra_upd_ack(struct msgb *old_msg)
{
@@ -471,7 +519,8 @@
/* Update Type 10.5.5.18 */
upd_type = *cur++ & 0x0f;
- DEBUGP(DMM, "GMM RA UPDATE REQUEST type=\"%s\" ", upd_name(upd_type));
+ DEBUGP(DMM, "-> GMM RA UPDATE REQUEST type=\"%s\" ",
+ get_value_string(gprs_upd_t_strs, upd_type));
/* Old routing area identification 10.5.5.15 */
gsm48_parse_ra(&old_ra_id, cur);
@@ -516,7 +565,7 @@
{
struct gsm48_hdr *gh = msgb_l3(msg);
- DEBUGP(DMM, "GPRS MM STATUS (cause: %s)\n",
+ DEBUGP(DMM, "-> GPRS MM STATUS (cause: %s)\n",
get_value_string(gmm_cause_names, gh->data[0]));
return 0;
@@ -541,19 +590,23 @@
case GSM48_MT_GMM_STATUS:
rc = gsm48_rx_gmm_status(msg);
break;
+ case GSM48_MT_GMM_DETACH_REQ:
+ rc = gsm48_rx_gmm_det_req(msg);
+ break;
case GSM48_MT_GMM_RA_UPD_COMPL:
/* only in case SGSN offered new P-TMSI */
case GSM48_MT_GMM_ATTACH_COMPL:
/* only in case SGSN offered new P-TMSI */
- case GSM48_MT_GMM_DETACH_REQ:
case GSM48_MT_GMM_PTMSI_REALL_COMPL:
case GSM48_MT_GMM_AUTH_CIPH_RESP:
DEBUGP(DMM, "Unimplemented GSM 04.08 GMM msg type 0x%02x\n",
gh->msg_type);
+ /* FIXME: Send GMM_CAUSE_MSGT_NOTEXIST_NOTIMPL */
break;
default:
DEBUGP(DMM, "Unknown GSM 04.08 GMM msg type 0x%02x\n",
gh->msg_type);
+ /* FIXME: Send GMM_CAUSE_MSGT_NOTEXIST_NOTIMPL */
break;
}
@@ -641,7 +694,7 @@
uint8_t *req_qos, *req_pdpa;
struct tlv_parsed tp;
- DEBUGP(DMM, "ACTIVATE PDP CONTEXT REQ: ");
+ DEBUGP(DMM, "-> ACTIVATE PDP CONTEXT REQ: ");
req_qos_len = act_req->data[0];
req_qos = act_req->data + 1; /* 10.5.6.5 */
req_pdpa_len = act_req->data[1 + req_qos_len];
@@ -679,11 +732,22 @@
break;
}
+ /* put the non-TLV elements in the TLV parser structure to
+ * pass them on to the SGSN / GTP code */
+ tp.lv[OSMO_IE_GSM_REQ_QOS].len = req_qos_len;
+ tp.lv[OSMO_IE_GSM_REQ_QOS].val = req_qos;
+ tp.lv[OSMO_IE_GSM_REQ_PDP_ADDR].len = req_pdpa_len;
+ tp.lv[OSMO_IE_GSM_REQ_PDP_ADDR].val = req_pdpa;
+
/* FIXME: parse TLV for AP name and protocol config options */
if (TLVP_PRESENT(&tp, GSM48_IE_GSM_APN)) {}
if (TLVP_PRESENT(&tp, GSM48_IE_GSM_PROTO_CONF_OPT)) {}
+#if 0
+ return sgsn_create_pdp_ctx(ggsn, &tp);
+#else
return gsm48_tx_gsm_act_pdp_acc(msg, act_req);
+#endif
}
/* Section 9.5.8: Deactivate PDP Context Request */
@@ -691,7 +755,7 @@
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
- DEBUGP(DMM, "DEACTIVATE PDP CONTEXT REQ (cause: %s)\n",
+ DEBUGP(DMM, "-> DEACTIVATE PDP CONTEXT REQ (cause: %s)\n",
get_value_string(gsm_cause_names, gh->data[0]));
return gsm48_tx_gsm_deact_pdp_acc(msg);
@@ -701,7 +765,7 @@
{
struct gsm48_hdr *gh = msgb_l3(msg);
- DEBUGP(DMM, "GPRS SM STATUS (cause: %s)\n",
+ DEBUGP(DMM, "-> GPRS SM STATUS (cause: %s)\n",
get_value_string(gsm_cause_names, gh->data[0]));
return 0;