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Create new 'gprs-sgsn' branch on top of 'gprs-conf' 

This branch contains the partial SGSN/GGSN implementation that
was originally developed as part of the gprs branch.
This commit is contained in:
Harald Welte 2010-03-14 15:45:01 +08:00
parent 20488d4881
commit 9ba500559a
4 changed files with 944 additions and 0 deletions
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138
openbsc/include/openbsc/gprs_bssgp.h Normal file
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#ifndef _GPRS_BSSGP_H
#define _GPRS_BSSGP_H
/* Section 11.3.26 / Table 11.27 */
enum bssgp_pdu_type {
/* PDUs between RL and BSSGP SAPs */
BSSGP_PDUT_DL_UNITDATA = 0x00,
BSSGP_PDUT_UL_UNITDATA = 0x01,
BSSGP_PDUT_RA_CAPABILITY = 0x02,
BSSGP_PDUT_PTM_UNITDATA = 0x03,
/* PDUs between GMM SAPs */
BSSGP_PDUT_PAGING_PS = 0x06,
BSSGP_PDUT_PAGING_CS = 0x07,
BSSGP_PDUT_RA_CAPA_UDPATE = 0x08,
BSSGP_PDUT_RA_CAPA_UPDATE_ACK = 0x09,
BSSGP_PDUT_RADIO_STATUS = 0x0a,
BSSGP_PDUT_SUSPEND = 0x0b,
BSSGP_PDUT_SUSPEND_ACK = 0x0c,
BSSGP_PDUT_SUSPEND_NACK = 0x0d,
BSSGP_PDUT_RESUME = 0x0e,
BSSGP_PDUT_RESUME_ACK = 0x0f,
BSSGP_PDUT_RESUME_NACK = 0x10,
/* PDus between NM SAPs */
BSSGP_PDUT_BVC_BLOCK = 0x20,
BSSGP_PDUT_BVC_BLOCK_ACK = 0x21,
BSSGP_PDUT_BVC_RESET = 0x22,
BSSGP_PDUT_BVC_RESET_ACK = 0x23,
BSSGP_PDUT_BVC_UNBLOCK = 0x24,
BSSGP_PDUT_BVC_UNBLOCK_ACK = 0x25,
BSSGP_PDUT_FLOW_CONTROL_BVC = 0x26,
BSSGP_PDUT_FLOW_CONTROL_BVC_ACK = 0x27,
BSSGP_PDUT_FLOW_CONTROL_MS = 0x28,
BSSGP_PDUT_FLOW_CONTROL_MS_ACK = 0x29,
BSSGP_PDUT_FLUSH_LL = 0x2a,
BSSGP_PDUT_FLUSH_LL_ACK = 0x2b,
BSSGP_PDUT_LLC_DISCARD = 0x2c,
BSSGP_PDUT_SGSN_INVOKE_TRACE = 0x40,
BSSGP_PDUT_STATUS = 0x41,
/* PDUs between PFM SAP's */
BSSGP_PDUT_DOWNLOAD_BSS_PFC = 0x50,
BSSGP_PDUT_CREATE_BSS_PFC = 0x51,
BSSGP_PDUT_CREATE_BSS_PFC_ACK = 0x52,
BSSGP_PDUT_CREATE_BSS_PFC_NACK = 0x53,
BSSGP_PDUT_MODIFY_BSS_PFC = 0x54,
BSSGP_PDUT_MODIFY_BSS_PFC_ACK = 0x55,
BSSGP_PDUT_DELETE_BSS_PFC = 0x56,
BSSGP_PDUT_DELETE_BSS_PFC_ACK = 0x57,
};
/* Section 10.2.1 and 10.2.2 */
struct bssgp_ud_hdr {
u_int8_t pdu_type;
u_int32_t tlli;
u_int8_t qos_profile[3];
u_int8_t data[0]; /* TLV's */
} __attribute__((packed));
struct bssgp_normal_hdr {
u_int8_t pdu_type;
u_int8_t data[0]; /* TLV's */
};
enum bssgp_iei_type {
BSSGP_IE_ALIGNMENT = 0x00,
BSSGP_IE_BMAX_DEFAULT_MS = 0x01,
BSSGP_IE_BSS_AREA_ID = 0x02,
BSSGP_IE_BUCKET_LEAK_RATE = 0x03,
BSSGP_IE_BVCI = 0x04,
BSSGP_IE_BVC_BUCKET_SIZE = 0x05,
BSSGP_IE_BVC_MEASUREMENT = 0x06,
BSSGP_IE_CAUSE = 0x07,
BSSGP_IE_CELL_ID = 0x08,
BSSGP_IE_CHAN_NEEDED = 0x09,
BSSGP_IE_DRX_PARAMS = 0x0a,
BSSGP_IE_EMLPP_PRIO = 0x0b,
BSSGP_IE_FLUSH_ACTION = 0x0c,
BSSGP_IE_IMSI = 0x0d,
BSSGP_IE_LLC_PDU = 0x0e,
BSSGP_IE_LLC_FRAMES_DISCARDED = 0x0f,
BSSGP_IE_LOCATION_AREA = 0x10,
BSSGP_IE_MOBILE_ID = 0x11,
BSSGP_IE_MS_BUCKET_SIZE = 0x12,
BSSGP_IE_MS_RADIO_ACCESS_CAP = 0x13,
BSSGP_IE_OMC_ID = 0x14,
BSSGP_IE_PDU_IN_ERROR = 0x15,
BSSGP_IE_PDU_LIFETIME = 0x16,
BSSGP_IE_PRIORITY = 0x17,
BSSGP_IE_QOS_PROFILE = 0x18,
BSSGP_IE_RADIO_CAUSE = 0x19,
BSSGP_IE_RA_CAP_UPD_CAUSE = 0x1a,
BSSGP_IE_ROUTEING_AREA = 0x1b,
BSSGP_IE_R_DEFAULT_MS = 0x1c,
BSSGP_IE_SUSPEND_REF_NR = 0x1d,
BSSGP_IE_TAG = 0x1e,
BSSGP_IE_TLLI = 0x1f,
BSSGP_IE_TMSI = 0x20,
BSSGP_IE_TRACE_REFERENC = 0x21,
BSSGP_IE_TRACE_TYPE = 0x22,
BSSGP_IE_TRANSACTION_ID = 0x23,
BSSGP_IE_TRIGGER_ID = 0x24,
BSSGP_IE_NUM_OCT_AFF = 0x25,
BSSGP_IE_LSA_ID_LIST = 0x26,
BSSGP_IE_LSA_INFORMATION = 0x27,
BSSGP_IE_PACKET_FLOW_ID = 0x28,
BSSGP_IE_PACKET_FLOW_TIMER = 0x29,
BSSGP_IE_AGG_BSS_QOS_PROFILE = 0x3a,
BSSGP_IE_FEATURE_BITMAP = 0x3b,
BSSGP_IE_BUCKET_FULL_RATIO = 0x3c,
BSSGP_IE_SERVICE_UTRAN_CCO = 0x3d,
};
/* Section 11.3.8 / Table 11.10: Cause coding */
enum gprs_bssgp_cause {
BSSGP_CAUSE_PROC_OVERLOAD = 0x00,
BSSGP_CAUSE_EQUIP_FAIL = 0x01,
BSSGP_CAUSE_TRASIT_NET_FAIL = 0x02,
BSSGP_CAUSE_CAPA_GREATER_0KPBS = 0x03,
BSSGP_CAUSE_UNKNOWN_MS = 0x04,
BSSGP_CAUSE_UNKNOWN_BVCI = 0x05,
BSSGP_CAUSE_CELL_TRAF_CONG = 0x06,
BSSGP_CAUSE_SGSN_CONG = 0x07,
BSSGP_CAUSE_OML_INTERV = 0x08,
BSSGP_CAUSE_BVCI_BLOCKED = 0x09,
BSSGP_CAUSE_PFC_CREATE_FAIL = 0x0a,
BSSGP_CAUSE_SEM_INCORR_PDU = 0x20,
BSSGP_CAUSE_INV_MAND_INF = 0x21,
BSSGP_CAUSE_MISSING_MAND_IE = 0x22,
BSSGP_CAUSE_MISSING_COND_IE = 0x23,
BSSGP_CAUSE_UNEXP_COND_IE = 0x24,
BSSGP_CAUSE_COND_IE_ERR = 0x25,
BSSGP_CAUSE_PDU_INCOMP_STATE = 0x26,
BSSGP_CAUSE_PROTO_ERR_UNSPEC = 0x27,
BSSGP_CAUSE_PDU_INCOMP_FEAT = 0x28,
};
extern int gprs_bssgp_rcvmsg(struct msgb *msg, u_int16_t bvci);
#endif /* _GPRS_BSSGP_H */

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openbsc/include/openbsc/gprs_ns.h Normal file
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#ifndef _GPRS_NS_H
#define _GPRS_NS_H
struct gprs_ns_hdr {
u_int8_t pdu_type;
u_int8_t data[0];
} __attribute__((packed));
/* TS 08.16, Section 10.3.7, Table 14 */
enum ns_pdu_type {
NS_PDUT_UNITDATA = 0x00,
NS_PDUT_RESET = 0x02,
NS_PDUT_RESET_ACK = 0x03,
NS_PDUT_BLOCK = 0x04,
NS_PDUT_BLOCK_ACK = 0x05,
NS_PDUT_UNBLOCK = 0x06,
NS_PDUT_UNBLOCK_ACK = 0x07,
NS_PDUT_STATUS = 0x08,
NS_PDUT_ALIVE = 0x0a,
NS_PDUT_ALIVE_ACK = 0x0b,
};
/* TS 08.16, Section 10.3, Table 12 */
enum ns_ctrl_ie {
NS_IE_CAUSE = 0x00,
NS_IE_VCI = 0x01,
NS_IE_PDU = 0x02,
NS_IE_BVCI = 0x03,
NS_IE_NSEI = 0x04,
};
/* TS 08.16, Section 10.3.2, Table 13 */
enum ns_cause {
NS_CAUSE_TRANSIT_FAIL = 0x00,
NS_CAUSE_OM_INTERVENTION = 0x01,
NS_CAUSE_EQUIP_FAIL = 0x02,
NS_CAUSE_NSVC_BLOCKED = 0x03,
NS_CAUSE_NSVC_UNKNOWN = 0x04,
NS_CAUSE_BVCI_UNKNOWN = 0x05,
NS_CAUSE_SEM_INCORR_PDU = 0x08,
NS_CAUSE_PDU_INCOMP_PSTATE = 0x0a,
NS_CAUSE_PROTO_ERR_UNSPEC = 0x0b,
NS_CAUSE_INVAL_ESSENT_IE = 0x0c,
NS_CAUSE_MISSING_ESSENT_IE = 0x0d,
};
/* a layer 1 entity transporting NS frames */
struct gprs_ns_link {
union {
struct {
int fd;
} ip;
};
};
int gprs_ns_rcvmsg(struct msgb *msg);
int gprs_ns_sendmsg(struct gprs_ns_link *link, u_int16_t bvci,
struct msgb *msg);
#endif

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/* GPRS BSSGP protocol implementation as per 3GPP TS 08.18 */
/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
*
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <errno.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <osmocore/msgb.h>
#include <osmocore/tlv.h>
#include <openbsc/debug.h>
#include <openbsc/gsm_data.h>
#include <openbsc/gsm_04_08_gprs.h>
#include <openbsc/gprs_bssgp.h>
#include <openbsc/gprs_llc.h>
#include <openbsc/gprs_ns.h>
/* global pointer to the gsm network data structure */
/* FIXME: this must go! */
extern struct gsm_network *bsc_gsmnet;
/* Chapter 11.3.9 / Table 11.10: Cause coding */
static const char *bssgp_cause_strings[] = {
[BSSGP_CAUSE_PROC_OVERLOAD] = "Processor overload",
[BSSGP_CAUSE_EQUIP_FAIL] = "Equipment Failure",
[BSSGP_CAUSE_TRASIT_NET_FAIL] = "Transit netowkr service failure",
[BSSGP_CAUSE_CAPA_GREATER_0KPBS]= "Transmission capacity modified",
[BSSGP_CAUSE_UNKNOWN_MS] = "Unknown MS",
[BSSGP_CAUSE_UNKNOWN_BVCI] = "Unknown BVCI",
[BSSGP_CAUSE_CELL_TRAF_CONG] = "Cell traffic congestion",
[BSSGP_CAUSE_SGSN_CONG] = "SGSN congestion",
[BSSGP_CAUSE_OML_INTERV] = "O&M intervention",
[BSSGP_CAUSE_BVCI_BLOCKED] = "BVCI blocked",
[BSSGP_CAUSE_PFC_CREATE_FAIL] = "PFC create failure",
[BSSGP_CAUSE_SEM_INCORR_PDU] = "Semantically incorrect PDU",
[BSSGP_CAUSE_INV_MAND_INF] = "Invalid mandatory information",
[BSSGP_CAUSE_MISSING_MAND_IE] = "Missing mandatory IE",
[BSSGP_CAUSE_MISSING_COND_IE] = "Missing conditional IE",
[BSSGP_CAUSE_UNEXP_COND_IE] = "Unexpected conditional IE",
[BSSGP_CAUSE_COND_IE_ERR] = "Conditional IE error",
[BSSGP_CAUSE_PDU_INCOMP_STATE] = "PDU incompatible with protocol state",
[BSSGP_CAUSE_PROTO_ERR_UNSPEC] = "Protocol error - unspecified",
[BSSGP_CAUSE_PDU_INCOMP_FEAT] = "PDU not compatible with feature set",
};
static const char *bssgp_cause_str(enum gprs_bssgp_cause cause)
{
if (cause >= ARRAY_SIZE(bssgp_cause_strings))
return "undefined";
if (bssgp_cause_strings[cause])
return bssgp_cause_strings[cause];
return "undefined";
}
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);
}
static inline struct msgb *bssgp_msgb_alloc(void)
{
return msgb_alloc_headroom(4096, 128, "BSSGP");
}
/* Transmit a simple response such as BLOCK/UNBLOCK/RESET ACK/NACK */
static int bssgp_tx_simple_bvci(u_int8_t pdu_type, u_int16_t bvci, u_int16_t ns_bvci)
{
struct msgb *msg = bssgp_msgb_alloc();
struct bssgp_normal_hdr *bgph =
(struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
u_int16_t _bvci;
bgph->pdu_type = pdu_type;
_bvci = htons(bvci);
msgb_tvlv_put(msg, BSSGP_IE_BVCI, 2, (u_int8_t *) &_bvci);
return gprs_ns_sendmsg(NULL, ns_bvci, msg);
}
/* Chapter 10.4.5: Flow Control BVC ACK */
static int bssgp_tx_fc_bvc_ack(u_int8_t tag, u_int16_t ns_bvci)
{
struct msgb *msg = bssgp_msgb_alloc();
struct bssgp_normal_hdr *bgph =
(struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
bgph->pdu_type = BSSGP_PDUT_FLOW_CONTROL_BVC_ACK;
msgb_tvlv_put(msg, BSSGP_IE_TAG, 1, &tag);
return gprs_ns_sendmsg(NULL, ns_bvci, msg);
}
/* Chapter 10.4.14: Status */
static int bssgp_tx_status(u_int8_t cause, u_int16_t *bvci, struct msgb *orig_msg)
{
struct msgb *msg = bssgp_msgb_alloc();
struct bssgp_normal_hdr *bgph =
(struct bssgp_normal_hdr *) msgb_put(msg, sizeof(*bgph));
DEBUGPC(DGPRS, "BSSGP: TX STATUS, cause=%s\n", bssgp_cause_str(cause));
bgph->pdu_type = BSSGP_PDUT_STATUS;
msgb_tvlv_put(msg, BSSGP_IE_CAUSE, 1, &cause);
if (bvci) {
u_int16_t _bvci = htons(*bvci);
msgb_tvlv_put(msg, BSSGP_IE_BVCI, 2, (u_int8_t *) &_bvci);
}
if (orig_msg)
msgb_tvlv_put(msg, BSSGP_IE_PDU_IN_ERROR,
msgb_l3len(orig_msg), orig_msg->l3h);
return gprs_ns_sendmsg(NULL, 0, msg);
}
/* Uplink unit-data */
static int bssgp_rx_ul_ud(struct msgb *msg, u_int16_t bvci)
{
struct bssgp_ud_hdr *budh = (struct bssgp_ud_hdr *) msg->l3h;
struct gsm_bts *bts;
int data_len = msgb_l3len(msg) - sizeof(*budh);
struct tlv_parsed tp;
int rc;
DEBUGP(DGPRS, "BSSGP UL-UD\n");
msg->tlli = ntohl(budh->tlli);
rc = bssgp_tlv_parse(&tp, budh->data, data_len);
/* Cell ID and LLC_PDU are the only mandatory IE */
if (!TLVP_PRESENT(&tp, BSSGP_IE_CELL_ID) ||
!TLVP_PRESENT(&tp, BSSGP_IE_LLC_PDU))
return -EIO;
/* Determine the BTS based on the Cell ID */
bts = gsm48_bts_by_ra_id(bsc_gsmnet,
TLVP_VAL(&tp, BSSGP_IE_CELL_ID),
TLVP_LEN(&tp, BSSGP_IE_CELL_ID));
if (bts)
msg->trx = bts->c0;
msg->llch = TLVP_VAL(&tp, BSSGP_IE_LLC_PDU);
return gprs_llc_rcvmsg(msg, &tp);
}
static int bssgp_rx_suspend(struct msgb *msg, u_int16_t bvci)
{
struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msg->l3h;
int data_len = msgb_l3len(msg) - sizeof(*bgph);
struct tlv_parsed tp;
int rc;
DEBUGP(DGPRS, "BSSGP SUSPEND\n");
rc = bssgp_tlv_parse(&tp, bgph->data, data_len);
if (rc < 0)
return rc;
if (!TLVP_PRESENT(&tp, BSSGP_IE_TLLI) ||
!TLVP_PRESENT(&tp, BSSGP_IE_ROUTEING_AREA))
return -EIO;
/* SEND SUSPEND_ACK or SUSPEND_NACK */
/* FIXME */
}
static int bssgp_rx_resume(struct msgb *msg, u_int16_t bvci)
{
struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msg->l3h;
int data_len = msgb_l3len(msg) - sizeof(*bgph);
struct tlv_parsed tp;
int rc;
DEBUGP(DGPRS, "BSSGP RESUME\n");
rc = bssgp_tlv_parse(&tp, bgph->data, data_len);
if (rc < 0)
return rc;
if (!TLVP_PRESENT(&tp, BSSGP_IE_TLLI) ||
!TLVP_PRESENT(&tp, BSSGP_IE_ROUTEING_AREA) ||
!TLVP_PRESENT(&tp, BSSGP_IE_SUSPEND_REF_NR))
return -EIO;
/* SEND RESUME_ACK or RESUME_NACK */
/* FIXME */
}
static int bssgp_rx_fc_bvc(struct msgb *msg, struct tlv_parsed *tp,
u_int16_t ns_bvci)
{
DEBUGP(DGPRS, "BSSGP FC BVC\n");
if (!TLVP_PRESENT(tp, BSSGP_IE_TAG) ||
!TLVP_PRESENT(tp, BSSGP_IE_BVC_BUCKET_SIZE) ||
!TLVP_PRESENT(tp, BSSGP_IE_BUCKET_LEAK_RATE) ||
!TLVP_PRESENT(tp, BSSGP_IE_BMAX_DEFAULT_MS) ||
!TLVP_PRESENT(tp, BSSGP_IE_R_DEFAULT_MS))
return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
/* Send FLOW_CONTROL_BVC_ACK */
return bssgp_tx_fc_bvc_ack(*TLVP_VAL(tp, BSSGP_IE_TAG), ns_bvci);
}
/* We expect msg->l3h to point to the BSSGP header */
int gprs_bssgp_rcvmsg(struct msgb *msg, u_int16_t ns_bvci)
{
struct bssgp_normal_hdr *bgph = (struct bssgp_normal_hdr *) msg->l3h;
struct tlv_parsed tp;
u_int8_t pdu_type = bgph->pdu_type;
int data_len = msgb_l3len(msg) - sizeof(*bgph);
u_int16_t bvci;
int rc = 0;
if (pdu_type != BSSGP_PDUT_UL_UNITDATA &&
pdu_type != BSSGP_PDUT_DL_UNITDATA)
rc = bssgp_tlv_parse(&tp, bgph->data, data_len);
switch (pdu_type) {
case BSSGP_PDUT_UL_UNITDATA:
/* some LLC data from the MS */
rc = bssgp_rx_ul_ud(msg, ns_bvci);
break;
case BSSGP_PDUT_RA_CAPABILITY:
/* BSS requests RA capability or IMSI */
DEBUGP(DGPRS, "BSSGP RA CAPABILITY UPDATE\n");
/* FIXME: send RA_CAPA_UPDATE_ACK */
break;
case BSSGP_PDUT_RADIO_STATUS:
DEBUGP(DGPRS, "BSSGP RADIO STATUS\n");
/* BSS informs us of some exception */
break;
case BSSGP_PDUT_SUSPEND:
/* MS wants to suspend */
rc = bssgp_rx_suspend(msg, ns_bvci);
break;
case BSSGP_PDUT_RESUME:
/* MS wants to resume */
rc = bssgp_rx_resume(msg, ns_bvci);
break;
case BSSGP_PDUT_FLUSH_LL:
/* BSS informs MS has moved to one cell to other cell */
DEBUGP(DGPRS, "BSSGP FLUSH LL\n");
/* Send FLUSH_LL_ACK */
break;
case BSSGP_PDUT_LLC_DISCARD:
/* BSS informs that some LLC PDU's have been discarded */
DEBUGP(DGPRS, "BSSGP LLC DISCARDED\n");
break;
case BSSGP_PDUT_FLOW_CONTROL_BVC:
/* BSS informs us of available bandwidth in Gb interface */
rc = bssgp_rx_fc_bvc(msg, &tp, ns_bvci);
break;
case BSSGP_PDUT_FLOW_CONTROL_MS:
/* BSS informs us of available bandwidth to one MS */
DEBUGP(DGPRS, "BSSGP FC MS\n");
/* Send FLOW_CONTROL_MS_ACK */
break;
case BSSGP_PDUT_BVC_BLOCK:
/* BSS tells us that BVC shall be blocked */
DEBUGP(DGPRS, "BSSGP BVC BLOCK ");
if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI) ||
!TLVP_PRESENT(&tp, BSSGP_IE_CAUSE))
goto err_mand_ie;
bvci = ntohs(*(u_int16_t *)TLVP_VAL(&tp, BSSGP_IE_BVCI));
DEBUGPC(DGPRS, "BVCI=%u, cause=%s\n", bvci,
bssgp_cause_str(*TLVP_VAL(&tp, BSSGP_IE_CAUSE)));
rc = bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_BLOCK_ACK,
bvci, ns_bvci);
break;
case BSSGP_PDUT_BVC_UNBLOCK:
/* BSS tells us that BVC shall be unblocked */
DEBUGP(DGPRS, "BSSGP BVC UNBLOCK ");
if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI))
goto err_mand_ie;
bvci = ntohs(*(u_int16_t *)TLVP_VAL(&tp, BSSGP_IE_BVCI));
DEBUGPC(DGPRS, "BVCI=%u\n", bvci);
rc = bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_UNBLOCK_ACK,
bvci, ns_bvci);
break;
case BSSGP_PDUT_BVC_RESET:
/* BSS tells us that BVC init is required */
DEBUGP(DGPRS, "BSSGP BVC RESET ");
if (!TLVP_PRESENT(&tp, BSSGP_IE_BVCI) ||
!TLVP_PRESENT(&tp, BSSGP_IE_CAUSE))
goto err_mand_ie;
bvci = ntohs(*(u_int16_t *)TLVP_VAL(&tp, BSSGP_IE_BVCI));
DEBUGPC(DGPRS, "BVCI=%u, cause=%s\n", bvci,
bssgp_cause_str(*TLVP_VAL(&tp, BSSGP_IE_CAUSE)));
rc = bssgp_tx_simple_bvci(BSSGP_PDUT_BVC_RESET_ACK,
bvci, ns_bvci);
break;
case BSSGP_PDUT_STATUS:
/* Some exception has occurred */
case BSSGP_PDUT_DOWNLOAD_BSS_PFC:
case BSSGP_PDUT_CREATE_BSS_PFC_ACK:
case BSSGP_PDUT_CREATE_BSS_PFC_NACK:
case BSSGP_PDUT_MODIFY_BSS_PFC:
case BSSGP_PDUT_DELETE_BSS_PFC_ACK:
DEBUGP(DGPRS, "BSSGP PDU type 0x%02x not [yet] implemented\n",
pdu_type);
break;
/* those only exist in the SGSN -> BSS direction */
case BSSGP_PDUT_DL_UNITDATA:
case BSSGP_PDUT_PAGING_PS:
case BSSGP_PDUT_PAGING_CS:
case BSSGP_PDUT_RA_CAPA_UPDATE_ACK:
case BSSGP_PDUT_SUSPEND_ACK:
case BSSGP_PDUT_SUSPEND_NACK:
case BSSGP_PDUT_RESUME_ACK:
case BSSGP_PDUT_RESUME_NACK:
case BSSGP_PDUT_FLUSH_LL_ACK:
case BSSGP_PDUT_FLOW_CONTROL_BVC_ACK:
case BSSGP_PDUT_FLOW_CONTROL_MS_ACK:
case BSSGP_PDUT_BVC_BLOCK_ACK:
case BSSGP_PDUT_BVC_UNBLOCK_ACK:
case BSSGP_PDUT_SGSN_INVOKE_TRACE:
DEBUGP(DGPRS, "BSSGP PDU type 0x%02x only exists in DL\n",
pdu_type);
rc = -EINVAL;
break;
default:
DEBUGP(DGPRS, "BSSGP PDU type 0x%02x unknown\n", pdu_type);
break;
}
return rc;
err_mand_ie:
return bssgp_tx_status(BSSGP_CAUSE_MISSING_MAND_IE, NULL, msg);
}
int gprs_bssgp_tx_dl_ud(struct msgb *msg)
{
struct gsm_bts *bts;
struct bssgp_ud_hdr *budh;
u_int8_t llc_pdu_tlv_hdr_len = 2;
u_int8_t *llc_pdu_tlv, *qos_profile;
u_int16_t pdu_lifetime = 1000; /* centi-seconds */
u_int8_t qos_profile_default[3] = { 0x00, 0x00, 0x21 };
u_int16_t msg_len = msg->len;
if (!msg->trx) {
DEBUGP(DGPRS, "Cannot transmit DL-UD without TRX assigned\n");
return -EINVAL;
}
bts = msg->trx->bts;
if (msg->len > TVLV_MAX_ONEBYTE)
llc_pdu_tlv_hdr_len += 1;
/* prepend the tag and length of the LLC-PDU TLV */
llc_pdu_tlv = msgb_push(msg, llc_pdu_tlv_hdr_len);
llc_pdu_tlv[0] = BSSGP_IE_LLC_PDU;
if (llc_pdu_tlv_hdr_len > 2) {
llc_pdu_tlv[1] = msg_len >> 8;
llc_pdu_tlv[2] = msg_len & 0xff;
} else {
llc_pdu_tlv[1] = msg_len & 0x3f;
llc_pdu_tlv[1] |= 0x80;
}
/* FIXME: optional elements */
/* prepend the pdu lifetime */
pdu_lifetime = htons(pdu_lifetime);
msgb_tvlv_push(msg, BSSGP_IE_PDU_LIFETIME, 2, (u_int8_t *)&pdu_lifetime);
/* prepend the QoS profile, TLLI and pdu type */
budh = (struct bssgp_ud_hdr *) msgb_push(msg, sizeof(*budh));
memcpy(budh->qos_profile, qos_profile_default, sizeof(qos_profile_default));
budh->tlli = htonl(msg->tlli);
budh->pdu_type = BSSGP_PDUT_DL_UNITDATA;
return gprs_ns_sendmsg(NULL, bts->gprs.cell.bvci, msg);
}

348
openbsc/src/gprs_ns.c Normal file
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/* 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) */
/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
*
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
/* Some introduction into NS: NS is used typically on top of frame relay,
* but in the ip.access world it is encapsulated in UDP packets. It serves
* as an intermediate shim betwen BSSGP and the underlying medium. It doesn't
* do much, apart from providing congestion notification and status indication.
*
* Terms:
* NS Network Service
* NSVC NS Virtual Connection
* NSEI NS Entity Identifier
* NSVL NS Virtual Link
* NSVLI NS Virtual Link Identifier
* BVC BSSGP Virtual Connection
* BVCI BSSGP Virtual Connection Identifier
* NSVCG NS Virtual Connection Goup
* Blocked NS-VC cannot be used for user traffic
* Alive Ability of a NS-VC to provide communication
*
* There can be multiple BSSGP virtual connections over one (group of) NSVC's. BSSGP will
* therefore identify the BSSGP virtual connection by a BVCI passed down to NS.
* NS then has to firgure out which NSVC's are responsible for this BVCI.
* Those mappings are administratively configured.
*/
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <openbsc/gsm_data.h>
#include <osmocore/msgb.h>
#include <osmocore/tlv.h>
#include <osmocore/talloc.h>
#include <openbsc/debug.h>
#include <openbsc/gprs_ns.h>
#include <openbsc/gprs_bssgp.h>
#define NS_ALLOC_SIZE 1024
static const struct tlv_definition ns_att_tlvdef = {
.def = {
[NS_IE_CAUSE] = { TLV_TYPE_TvLV, 0 },
[NS_IE_VCI] = { TLV_TYPE_TvLV, 0 },
[NS_IE_PDU] = { TLV_TYPE_TvLV, 0 },
[NS_IE_BVCI] = { TLV_TYPE_TvLV, 0 },
[NS_IE_NSEI] = { TLV_TYPE_TvLV, 0 },
},
};
#define NSE_S_BLOCKED 0x0001
#define NSE_S_ALIVE 0x0002
struct gprs_nsvc {
struct llist_head list;
u_int16_t nsei; /* end-to-end significance */
u_int16_t nsvci; /* uniquely identifies NS-VC at SGSN */
u_int32_t state;
struct timer_list alive_timer;
int timer_is_tns_alive;
int alive_retries;
};
/* FIXME: dynamically search for the matching NSVC */
static struct gprs_nsvc dummy_nsvc = { .state = NSE_S_BLOCKED | NSE_S_ALIVE };
/* Section 10.3.2, Table 13 */
static const char *ns_cause_str[] = {
[NS_CAUSE_TRANSIT_FAIL] = "Transit network failure",
[NS_CAUSE_OM_INTERVENTION] = "O&M intervention",
[NS_CAUSE_EQUIP_FAIL] = "Equipment failure",
[NS_CAUSE_NSVC_BLOCKED] = "NS-VC blocked",
[NS_CAUSE_NSVC_UNKNOWN] = "NS-VC unknown",
[NS_CAUSE_BVCI_UNKNOWN] = "BVCI unknown",
[NS_CAUSE_SEM_INCORR_PDU] = "Semantically incorrect PDU",
[NS_CAUSE_PDU_INCOMP_PSTATE] = "PDU not compatible with protocol state",
[NS_CAUSE_PROTO_ERR_UNSPEC] = "Protocol error, unspecified",
[NS_CAUSE_INVAL_ESSENT_IE] = "Invalid essential IE",
[NS_CAUSE_MISSING_ESSENT_IE] = "Missing essential IE",
};
static const char *gprs_ns_cause_str(enum ns_cause cause)
{
if (cause >= ARRAY_SIZE(ns_cause_str))
return "undefined";
if (ns_cause_str[cause])
return ns_cause_str[cause];
return "undefined";
}
static int gprs_ns_tx(struct msgb *msg)
{
return ipac_gprs_send(msg);
}
static int gprs_ns_tx_simple(struct gprs_ns_link *link, u_int8_t pdu_type)
{
struct msgb *msg = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
struct gprs_ns_hdr *nsh;
if (!msg)
return -ENOMEM;
nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
nsh->pdu_type = pdu_type;
return gprs_ns_tx(msg);
}
#define NS_TIMER_ALIVE 3, 0 /* after 3 seconds without response, we retry */
#define NS_TIMER_TEST 30, 0 /* every 10 seconds we check if the BTS is still alive */
#define NS_ALIVE_RETRIES 10 /* after 3 failed retransmit we declare BTS as dead */
static void gprs_ns_alive_cb(void *data)
{
struct gprs_nsvc *nsvc = data;
if (nsvc->timer_is_tns_alive) {
/* Tns-alive case: we expired without response ! */
nsvc->alive_retries++;
if (nsvc->alive_retries > NS_ALIVE_RETRIES) {
/* mark as dead and blocked */
nsvc->state = NSE_S_BLOCKED;
DEBUGP(DGPRS, "Tns-alive more then %u retries, "
" blocking NS-VC\n", NS_ALIVE_RETRIES);
/* FIXME: inform higher layers */
return;
}
} else {
/* Tns-test case: send NS-ALIVE PDU */
gprs_ns_tx_simple(NULL, NS_PDUT_ALIVE);
/* start Tns-alive timer */
nsvc->timer_is_tns_alive = 1;
}
bsc_schedule_timer(&nsvc->alive_timer, NS_TIMER_ALIVE);
}
/* Section 9.2.6 */
static int gprs_ns_tx_reset_ack(u_int16_t nsvci, u_int16_t nsei)
{
struct msgb *msg = msgb_alloc(NS_ALLOC_SIZE, "GPRS/NS");
struct gprs_ns_hdr *nsh;
if (!msg)
return -ENOMEM;
nsvci = htons(nsvci);
nsei = htons(nsei);
nsh = (struct gprs_ns_hdr *) msgb_put(msg, sizeof(*nsh));
nsh->pdu_type = NS_PDUT_RESET_ACK;
msgb_tvlv_put(msg, NS_IE_VCI, 2, (u_int8_t *)&nsvci);
msgb_tvlv_put(msg, NS_IE_NSEI, 2, (u_int8_t *)&nsei);
return gprs_ns_tx(msg);
}
/* Section 9.2.10: transmit side */
int gprs_ns_sendmsg(struct gprs_ns_link *link, u_int16_t bvci,
struct msgb *msg)
{
struct gprs_ns_hdr *nsh;
nsh = (struct gprs_ns_hdr *) msgb_push(msg, sizeof(*nsh) + 3);
if (!nsh) {
DEBUGP(DGPRS, "Not enough headroom for NS header\n");
return -EIO;
}
nsh->pdu_type = NS_PDUT_UNITDATA;
/* spare octet in data[0] */
nsh->data[1] = bvci >> 8;
nsh->data[2] = bvci & 0xff;
return gprs_ns_tx(msg);
}
/* Section 9.2.10: receive side */
static int gprs_ns_rx_unitdata(struct msgb *msg)
{
struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *)msg->l2h;
u_int16_t bvci;
/* spare octet in data[0] */
bvci = nsh->data[1] << 8 | nsh->data[2];
msg->l3h = &nsh->data[3];
/* call upper layer (BSSGP) */
return gprs_bssgp_rcvmsg(msg, bvci);
}
/* Section 9.2.7 */
static int gprs_ns_rx_status(struct msgb *msg)
{
struct gprs_ns_hdr *nsh = msg->l2h;
struct tlv_parsed tp;
u_int8_t cause;
int rc;
DEBUGP(DGPRS, "NS STATUS ");
rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, msgb_l2len(msg), 0, 0);
if (!TLVP_PRESENT(&tp, NS_IE_CAUSE)) {
DEBUGPC(DGPRS, "missing cause IE\n");
return -EINVAL;
}
cause = *TLVP_VAL(&tp, NS_IE_CAUSE);
DEBUGPC(DGPRS, "cause=%s\n", gprs_ns_cause_str(cause));
return 0;
}
/* Section 7.3 */
static int gprs_ns_rx_reset(struct msgb *msg)
{
struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h;
struct gprs_nsvc *nsvc = &dummy_nsvc;
struct tlv_parsed tp;
u_int8_t *cause;
u_int16_t *nsvci, *nsei;
int rc;
DEBUGP(DGPRS, "NS RESET ");
rc = tlv_parse(&tp, &ns_att_tlvdef, nsh->data, msgb_l2len(msg), 0, 0);
if (!TLVP_PRESENT(&tp, NS_IE_CAUSE) ||
!TLVP_PRESENT(&tp, NS_IE_VCI) ||
!TLVP_PRESENT(&tp, NS_IE_NSEI)) {
/* FIXME: respond with NS_CAUSE_MISSING_ESSENT_IE */
DEBUGPC(DGPRS, "Missing mandatory IE\n");
return -EINVAL;
}
cause = (u_int8_t *) TLVP_VAL(&tp, NS_IE_CAUSE);
nsvci = (u_int16_t *) TLVP_VAL(&tp, NS_IE_VCI);
nsei = (u_int16_t *) TLVP_VAL(&tp, NS_IE_NSEI);
*nsvci = ntohs(*nsvci);
*nsei = ntohs(*nsei);
DEBUGPC(DGPRS, "cause=%s, NSVCI=%u, NSEI=%u\n",
gprs_ns_cause_str(*cause), *nsvci, *nsei);
/* mark the NS-VC as blocked and alive */
nsvc->state = NSE_S_BLOCKED | NSE_S_ALIVE;
nsvc->nsei = *nsei;
nsvc->nsvci = *nsvci;
/* start the test procedure */
nsvc->alive_timer.cb = gprs_ns_alive_cb;
nsvc->alive_timer.data = nsvc;
bsc_schedule_timer(&nsvc->alive_timer, NS_TIMER_ALIVE);
return gprs_ns_tx_reset_ack(*nsvci, *nsei);
}
/* main entry point, here incoming NS frames enter */
int gprs_ns_rcvmsg(struct msgb *msg)
{
struct gprs_ns_hdr *nsh = (struct gprs_ns_hdr *) msg->l2h;
struct gprs_nsvc *nsvc = &dummy_nsvc;
int rc = 0;
switch (nsh->pdu_type) {
case NS_PDUT_ALIVE:
/* remote end inquires whether we're still alive,
* we need to respond with ALIVE_ACK */
rc = gprs_ns_tx_simple(NULL, NS_PDUT_ALIVE_ACK);
break;
case NS_PDUT_ALIVE_ACK:
/* stop Tns-alive */
bsc_del_timer(&nsvc->alive_timer);
/* start Tns-test */
nsvc->timer_is_tns_alive = 0;
bsc_schedule_timer(&nsvc->alive_timer, NS_TIMER_TEST);
break;
case NS_PDUT_UNITDATA:
/* actual user data */
rc = gprs_ns_rx_unitdata(msg);
break;
case NS_PDUT_STATUS:
rc = gprs_ns_rx_status(msg);
break;
case NS_PDUT_RESET:
rc = gprs_ns_rx_reset(msg);
break;
case NS_PDUT_RESET_ACK:
/* FIXME: mark remote NS-VC as blocked + active */
break;
case NS_PDUT_UNBLOCK:
/* Section 7.2: unblocking procedure */
DEBUGP(DGPRS, "NS UNBLOCK\n");
nsvc->state &= ~NSE_S_BLOCKED;
rc = gprs_ns_tx_simple(NULL, NS_PDUT_UNBLOCK_ACK);
break;
case NS_PDUT_UNBLOCK_ACK:
/* FIXME: mark remote NS-VC as unblocked + active */
break;
case NS_PDUT_BLOCK:
DEBUGP(DGPRS, "NS BLOCK\n");
nsvc->state |= NSE_S_BLOCKED;
rc = gprs_ns_tx_simple(NULL, NS_PDUT_UNBLOCK_ACK);
break;
case NS_PDUT_BLOCK_ACK:
/* FIXME: mark remote NS-VC as blocked + active */
break;
default:
DEBUGP(DGPRS, "Unknown NS PDU type 0x%02x\n", nsh->pdu_type);
rc = -EINVAL;
break;
}
return rc;
}