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osmo-bsc/src/gprs/gprs_gmm.c

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/* GSM Mobile Radio Interface Layer 3 messages on the A-bis interface
* 3GPP TS 04.08 version 7.21.0 Release 1998 / ETSI TS 100 940 V7.21.0 */
/* (C) 2009-2015 by Harald Welte <laforge@gnumonks.org>
* (C) 2010 by On-Waves
*
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation; either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <errno.h>
#include <stdbool.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <openssl/rand.h>
#include "bscconfig.h"
#include <openbsc/db.h>
#include <osmocom/core/msgb.h>
#include <osmocom/gsm/tlv.h>
#include <osmocom/gsm/gsm_utils.h>
#include <osmocom/core/signal.h>
#include <osmocom/core/talloc.h>
#include <osmocom/core/rate_ctr.h>
#include <osmocom/core/utils.h>
#include <osmocom/crypt/auth.h>
#include <osmocom/gsm/apn.h>
#include <osmocom/gsm/protocol/gsm_04_08_gprs.h>
#include <osmocom/gprs/gprs_bssgp.h>
#ifdef BUILD_IU
#include <osmocom/ranap/ranap_ies_defs.h>
#include <osmocom/ranap/ranap_msg_factory.h>
#endif
#include <openbsc/debug.h>
#include <openbsc/gsm_data.h>
#include <openbsc/gsm_subscriber.h>
#include <openbsc/gsm_04_08.h>
#include <openbsc/paging.h>
#include <openbsc/transaction.h>
#include <openbsc/gprs_llc.h>
#include <openbsc/gprs_sgsn.h>
#include <openbsc/gprs_gmm.h>
#include <openbsc/gprs_utils.h>
#include <openbsc/gprs_subscriber.h>
#include <openbsc/sgsn.h>
#include <openbsc/signal.h>
#include <openbsc/iu.h>
#include <openbsc/gprs_sndcp.h>
#include <pdp.h>
#define PTMSI_ALLOC
extern struct sgsn_instance *sgsn;
static const struct tlv_definition gsm48_gmm_att_tlvdef = {
.def = {
[GSM48_IE_GMM_CIPH_CKSN] = { TLV_TYPE_FIXED, 1 },
[GSM48_IE_GMM_TIMER_READY] = { TLV_TYPE_TV, 1 },
[GSM48_IE_GMM_ALLOC_PTMSI] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GMM_PTMSI_SIG] = { TLV_TYPE_FIXED, 3 },
[GSM48_IE_GMM_AUTH_RAND] = { TLV_TYPE_FIXED, 16 },
[GSM48_IE_GMM_AUTH_SRES] = { TLV_TYPE_FIXED, 4 },
[GSM48_IE_GMM_AUTH_RES_EXT] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GMM_AUTH_FAIL_PAR] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GMM_IMEISV] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GMM_DRX_PARAM] = { TLV_TYPE_FIXED, 2 },
[GSM48_IE_GMM_MS_NET_CAPA] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GMM_PDP_CTX_STATUS] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GMM_PS_LCS_CAPA] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GMM_GMM_MBMS_CTX_ST] = { TLV_TYPE_TLV, 0 },
},
};
static const struct tlv_definition gsm48_sm_att_tlvdef = {
.def = {
[GSM48_IE_GSM_APN] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GSM_PROTO_CONF_OPT] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GSM_PDP_ADDR] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GSM_AA_TMR] = { TLV_TYPE_TV, 1 },
[GSM48_IE_GSM_NAME_FULL] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GSM_NAME_SHORT] = { TLV_TYPE_TLV, 0 },
[GSM48_IE_GSM_TIMEZONE] = { TLV_TYPE_FIXED, 1 },
[GSM48_IE_GSM_UTC_AND_TZ] = { TLV_TYPE_FIXED, 7 },
[GSM48_IE_GSM_LSA_ID] = { TLV_TYPE_TLV, 0 },
},
};
static const struct value_string gprs_pmm_state_names[] = {
{ PMM_DETACHED, "PMM DETACH" },
{ PMM_CONNECTED, "PMM CONNECTED" },
{ PMM_IDLE, "PMM IDLE" },
{ MM_IDLE, "MM IDLE" },
{ MM_READY, "MM READY" },
{ MM_STANDBY, "MM STANDBY" },
{ 0, NULL }
};
static int gsm48_gmm_authorize(struct sgsn_mm_ctx *ctx);
static void mmctx_change_gtpu_endpoints_to_sgsn(struct sgsn_mm_ctx *mm_ctx)
{
struct sgsn_pdp_ctx *pdp;
llist_for_each_entry(pdp, &mm_ctx->pdp_list, list) {
sgsn_pdp_upd_gtp_u(pdp,
&sgsn->cfg.gtp_listenaddr.sin_addr,
sizeof(sgsn->cfg.gtp_listenaddr.sin_addr));
}
}
void mmctx_set_pmm_state(struct sgsn_mm_ctx *ctx, enum gprs_pmm_state state)
{
if (ctx->ran_type != MM_CTX_T_UTRAN_Iu)
return;
if (ctx->pmm_state == state)
return;
LOGMMCTXP(LOGL_INFO, ctx, "Changing PMM state from %s to %s\n",
get_value_string(gprs_pmm_state_names, ctx->pmm_state),
get_value_string(gprs_pmm_state_names, state));
switch (state) {
case PMM_IDLE:
/* TODO: start RA Upd timer */
mmctx_change_gtpu_endpoints_to_sgsn(ctx);
break;
case PMM_CONNECTED:
break;
default:
break;
}
ctx->pmm_state = state;
}
void mmctx_set_mm_state(struct sgsn_mm_ctx *ctx, enum gprs_pmm_state state)
{
if (ctx->ran_type != MM_CTX_T_GERAN_Gb)
return;
if (ctx->pmm_state == state)
return;
LOGMMCTXP(LOGL_INFO, ctx, "Changing MM state from %s to %s\n",
get_value_string(gprs_pmm_state_names, ctx->pmm_state),
get_value_string(gprs_pmm_state_names, state));
ctx->pmm_state = state;
}
#ifdef BUILD_IU
int sgsn_ranap_rab_ass_resp(struct sgsn_mm_ctx *ctx, RANAP_RAB_SetupOrModifiedItemIEs_t *setup_ies);
int sgsn_ranap_iu_event(struct ue_conn_ctx *ctx, enum iu_event_type type, void *data)
{
struct sgsn_mm_ctx *mm;
int rc = -1;
mm = sgsn_mm_ctx_by_ue_ctx(ctx);
if (!mm) {
LOGP(DRANAP, LOGL_NOTICE, "Cannot find mm ctx for IU event %i!\n", type);
return rc;
}
switch (type) {
case IU_EVENT_RAB_ASSIGN:
rc = sgsn_ranap_rab_ass_resp(mm, (RANAP_RAB_SetupOrModifiedItemIEs_t *)data);
break;
case IU_EVENT_IU_RELEASE:
/* fall thru */
case IU_EVENT_LINK_INVALIDATED:
/* Clean up ue_conn_ctx here */
LOGMMCTXP(LOGL_INFO, mm, "IU release for imsi %s\n", mm->imsi);
if (mm->pmm_state == PMM_CONNECTED)
mmctx_set_pmm_state(mm, PMM_IDLE);
rc = 0;
break;
case IU_EVENT_SECURITY_MODE_COMPLETE:
/* Continue authentication here */
mm->iu.ue_ctx->integrity_active = 1;
rc = gsm48_gmm_authorize(mm);
break;
default:
LOGP(DRANAP, LOGL_NOTICE, "Unknown event received: %i\n", type);
rc = -1;
break;
}
return rc;
}
#endif
/* Our implementation, should be kept in SGSN */
static void mmctx_timer_cb(void *_mm);
static void mmctx_timer_start(struct sgsn_mm_ctx *mm, unsigned int T,
unsigned int seconds)
{
if (osmo_timer_pending(&mm->timer))
LOGMMCTXP(LOGL_ERROR, mm, "Starting MM timer %u while old "
"timer %u pending\n", T, mm->T);
mm->T = T;
mm->num_T_exp = 0;
/* FIXME: we should do this only once ? */
osmo_timer_setup(&mm->timer, mmctx_timer_cb, mm);
osmo_timer_schedule(&mm->timer, seconds, 0);
}
static void mmctx_timer_stop(struct sgsn_mm_ctx *mm, unsigned int T)
{
if (mm->T != T)
LOGMMCTXP(LOGL_ERROR, mm, "Stopping MM timer %u but "
"%u is running\n", T, mm->T);
osmo_timer_del(&mm->timer);
}
time_t gprs_max_time_to_idle(void)
{
return sgsn->cfg.timers.T3314 + (sgsn->cfg.timers.T3312 + 4 * 60);
}
/* Send a message through the underlying layer.
* For param encryptable, see 3GPP TS 24.008 § 4.7.1.2 and
* gsm48_hdr_gmm_cipherable(). Pass false for not cipherable messages. */
static int gsm48_gmm_sendmsg(struct msgb *msg, int command,
struct sgsn_mm_ctx *mm, bool encryptable)
{
if (mm) {
rate_ctr_inc(&mm->ctrg->ctr[GMM_CTR_PKTS_SIG_OUT]);
#ifdef BUILD_IU
if (mm->ran_type == MM_CTX_T_UTRAN_Iu)
return iu_tx(msg, GPRS_SAPI_GMM);
#endif
}
#ifdef BUILD_IU
/* In Iu mode, msg->dst contains the ue_conn_ctx pointer, in Gb mode
* dst is empty. */
/* FIXME: have a more explicit indicator for Iu messages */
if (msg->dst)
return iu_tx(msg, GPRS_SAPI_GMM);
#endif
/* caller needs to provide TLLI, BVCI and NSEI */
return gprs_llc_tx_ui(msg, GPRS_SAPI_GMM, command, mm, encryptable);
}
/* copy identifiers from old message to new message, this
* is required so lower layers can route it correctly */
static void gmm_copy_id(struct msgb *msg, const struct msgb *old)
{
msgb_tlli(msg) = msgb_tlli(old);
msgb_bvci(msg) = msgb_bvci(old);
msgb_nsei(msg) = msgb_nsei(old);
msg->dst = old->dst;
}
/* Store BVCI/NSEI in MM context */
static void msgid2mmctx(struct sgsn_mm_ctx *mm, const struct msgb *msg)
{
mm->gb.bvci = msgb_bvci(msg);
mm->gb.nsei = msgb_nsei(msg);
/* In case a Iu connection is reconnected we need to update the ue ctx */
mm->iu.ue_ctx = msg->dst;
}
/* Store BVCI/NSEI in MM context */
static void mmctx2msgid(struct msgb *msg, const struct sgsn_mm_ctx *mm)
{
msgb_tlli(msg) = mm->gb.tlli;
msgb_bvci(msg) = mm->gb.bvci;
msgb_nsei(msg) = mm->gb.nsei;
msg->dst = mm->iu.ue_ctx;
}
static void mm_ctx_cleanup_free(struct sgsn_mm_ctx *ctx, const char *log_text)
{
LOGMMCTXP(LOGL_INFO, ctx, "Cleaning MM context due to %s\n", log_text);
/* Mark MM state as deregistered */
ctx->gmm_state = GMM_DEREGISTERED;
mmctx_set_pmm_state(ctx, PMM_DETACHED);
mmctx_set_pmm_state(ctx, MM_IDLE);
sgsn_mm_ctx_cleanup_free(ctx);
}
/* Chapter 9.4.18 */
static int _tx_status(struct msgb *msg, uint8_t cause,
struct sgsn_mm_ctx *mmctx, int sm)
{
struct gsm48_hdr *gh;
/* MMCTX might be NULL! */
DEBUGP(DMM, "<- GPRS MM STATUS (cause: %s)\n",
get_value_string(gsm48_gmm_cause_names, cause));
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
if (sm) {
gh->proto_discr = GSM48_PDISC_SM_GPRS;
gh->msg_type = GSM48_MT_GSM_STATUS;
} else {
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_STATUS;
}
gh->data[0] = cause;
return gsm48_gmm_sendmsg(msg, 0, mmctx, true);
}
static int gsm48_tx_gmm_status(struct sgsn_mm_ctx *mmctx, uint8_t cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 GMM STATUS");
mmctx2msgid(msg, mmctx);
return _tx_status(msg, cause, mmctx, 0);
}
static int gsm48_tx_sm_status(struct sgsn_mm_ctx *mmctx, uint8_t cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 SM STATUS");
mmctx2msgid(msg, mmctx);
return _tx_status(msg, cause, mmctx, 1);
}
static int _tx_detach_req(struct msgb *msg, uint8_t detach_type, uint8_t cause,
struct sgsn_mm_ctx *mmctx)
{
struct gsm48_hdr *gh;
/* MMCTX might be NULL! */
DEBUGP(DMM, "<- GPRS MM DETACH REQ (type: %s, cause: %s)\n",
get_value_string(gprs_det_t_mt_strs, detach_type),
get_value_string(gsm48_gmm_cause_names, cause));
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_DETACH_REQ;
gh->data[0] = detach_type & 0x07;
msgb_tv_put(msg, GSM48_IE_GMM_CAUSE, cause);
return gsm48_gmm_sendmsg(msg, 0, mmctx, true);
}
static int gsm48_tx_gmm_detach_req(struct sgsn_mm_ctx *mmctx,
uint8_t detach_type, uint8_t cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 DET REQ");
mmctx2msgid(msg, mmctx);
return _tx_detach_req(msg, detach_type, cause, mmctx);
}
static int gsm48_tx_gmm_detach_req_oldmsg(struct msgb *oldmsg,
uint8_t detach_type, uint8_t cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 DET OLD");
gmm_copy_id(msg, oldmsg);
return _tx_detach_req(msg, detach_type, cause, NULL);
}
static struct gsm48_qos default_qos = {
.delay_class = 4, /* best effort */
.reliab_class = GSM48_QOS_RC_LLC_UN_RLC_ACK_DATA_PROT,
.peak_tput = GSM48_QOS_PEAK_TPUT_32000bps,
.preced_class = GSM48_QOS_PC_NORMAL,
.mean_tput = GSM48_QOS_MEAN_TPUT_BEST_EFFORT,
.traf_class = GSM48_QOS_TC_INTERACTIVE,
.deliv_order = GSM48_QOS_DO_UNORDERED,
.deliv_err_sdu = GSM48_QOS_ERRSDU_YES,
.max_sdu_size = GSM48_QOS_MAXSDU_1520,
.max_bitrate_up = GSM48_QOS_MBRATE_63k,
.max_bitrate_down = GSM48_QOS_MBRATE_63k,
.resid_ber = GSM48_QOS_RBER_5e_2,
.sdu_err_ratio = GSM48_QOS_SERR_1e_2,
.handling_prio = 3,
.xfer_delay = 0x10, /* 200ms */
.guar_bitrate_up = GSM48_QOS_MBRATE_0k,
.guar_bitrate_down = GSM48_QOS_MBRATE_0k,
.sig_ind = 0, /* not optimised for signalling */
.max_bitrate_down_ext = 0, /* use octet 9 */
.guar_bitrate_down_ext = 0, /* use octet 13 */
};
/* Chapter 9.4.2: Attach accept */
static int gsm48_tx_gmm_att_ack(struct sgsn_mm_ctx *mm)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 ATT ACK");
struct gsm48_hdr *gh;
struct gsm48_attach_ack *aa;
uint8_t *mid;
#if 0
uint8_t *ptsig;
#endif
LOGMMCTXP(LOGL_INFO, mm, "<- GPRS ATTACH ACCEPT (new P-TMSI=0x%08x)\n", mm->p_tmsi);
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_ATTACH_ACKED]);
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_ATTACH_ACK;
aa = (struct gsm48_attach_ack *) msgb_put(msg, sizeof(*aa));
aa->force_stby = 0; /* not indicated */
aa->att_result = 1; /* GPRS only */
aa->ra_upd_timer = gprs_secs_to_tmr_floor(sgsn->cfg.timers.T3312);
aa->radio_prio = 4; /* lowest */
gsm48_construct_ra(aa->ra_id.digits, &mm->ra);
#if 0
/* Optional: P-TMSI signature */
msgb_v_put(msg, GSM48_IE_GMM_PTMSI_SIG);
ptsig = msgb_put(msg, 3);
ptsig[0] = mm->p_tmsi_sig >> 16;
ptsig[1] = mm->p_tmsi_sig >> 8;
ptsig[2] = mm->p_tmsi_sig & 0xff;
#endif
/* Optional: Negotiated Ready timer value
* (fixed 44s, default value, GSM 04.08, table 11.4a) to safely limit
* the inactivity time READY->STANDBY.
*/
msgb_tv_put(msg, GSM48_IE_GMM_TIMER_READY,
gprs_secs_to_tmr_floor(sgsn->cfg.timers.T3314));
#ifdef PTMSI_ALLOC
/* Optional: Allocated P-TMSI */
mid = msgb_put(msg, GSM48_MID_TMSI_LEN);
gsm48_generate_mid_from_tmsi(mid, mm->p_tmsi);
mid[0] = GSM48_IE_GMM_ALLOC_PTMSI;
#endif
/* Optional: MS-identity (combined attach) */
/* Optional: GMM cause (partial attach result for combined attach) */
return gsm48_gmm_sendmsg(msg, 0, mm, true);
}
/* Chapter 9.4.5: Attach reject */
static int _tx_gmm_att_rej(struct msgb *msg, uint8_t gmm_cause,
const struct sgsn_mm_ctx *mm)
{
struct gsm48_hdr *gh;
LOGMMCTXP(LOGL_NOTICE, mm, "<- GPRS ATTACH REJECT: %s\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause));
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_ATTACH_REJECTED]);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_ATTACH_REJ;
gh->data[0] = gmm_cause;
return gsm48_gmm_sendmsg(msg, 0, NULL, false);
}
static int gsm48_tx_gmm_att_rej_oldmsg(const struct msgb *old_msg,
uint8_t gmm_cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 ATT REJ OLD");
gmm_copy_id(msg, old_msg);
return _tx_gmm_att_rej(msg, gmm_cause, NULL);
}
static int gsm48_tx_gmm_att_rej(struct sgsn_mm_ctx *mm,
uint8_t gmm_cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 ATT REJ");
mmctx2msgid(msg, mm);
return _tx_gmm_att_rej(msg, gmm_cause, mm);
}
/* Chapter 9.4.6.2 Detach accept */
static int _tx_detach_ack(struct msgb *msg, uint8_t force_stby,
struct sgsn_mm_ctx *mm)
{
struct gsm48_hdr *gh;
/* MMCTX might be NULL! */
DEBUGP(DMM, "<- GPRS MM DETACH ACC (force-standby: %d)\n", force_stby);
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_DETACH_ACKED]);
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, mm, true);
}
static int gsm48_tx_gmm_det_ack(struct sgsn_mm_ctx *mm, uint8_t force_stby)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 DET ACK");
mmctx2msgid(msg, mm);
return _tx_detach_ack(msg, force_stby, mm);
}
static int gsm48_tx_gmm_det_ack_oldmsg(struct msgb *oldmsg, uint8_t force_stby)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 DET ACK OLD");
gmm_copy_id(msg, oldmsg);
return _tx_detach_ack(msg, force_stby, NULL);
}
/* Transmit Chapter 9.4.12 Identity Request */
static int gsm48_tx_gmm_id_req(struct sgsn_mm_ctx *mm, uint8_t id_type)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 ID REQ");
struct gsm48_hdr *gh;
LOGMMCTXP(LOGL_DEBUG, mm, "<- GPRS IDENTITY REQUEST: mi_type=%s\n",
gsm48_mi_type_name(id_type));
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_ID_REQ;
/* 10.5.5.9 ID type 2 + identity type and 10.5.5.7 'force to standby' IE */
gh->data[0] = id_type & 0xf;
return gsm48_gmm_sendmsg(msg, 1, mm, false);
}
/* determine if the MS/UE supports R99 or later */
static bool mmctx_is_r99(const struct sgsn_mm_ctx *mm)
{
if (mm->ms_network_capa.len < 1)
return false;
if (mm->ms_network_capa.buf[0] & 0x01)
return true;
return false;
}
/* 3GPP TS 24.008 Section 9.4.9: Authentication and Ciphering Request */
static int gsm48_tx_gmm_auth_ciph_req(struct sgsn_mm_ctx *mm,
const struct osmo_auth_vector *vec,
uint8_t key_seq, bool force_standby)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 AUTH CIPH REQ");
struct gsm48_hdr *gh;
struct gsm48_auth_ciph_req *acreq;
uint8_t *m_rand, *m_cksn, rbyte;
LOGMMCTXP(LOGL_INFO, mm, "<- GPRS AUTH AND CIPHERING REQ (rand = %s",
osmo_hexdump(vec->rand, sizeof(vec->rand)));
if (mmctx_is_r99(mm) && vec
&& (vec->auth_types & OSMO_AUTH_TYPE_UMTS)) {
LOGPC(DMM, LOGL_INFO, ", autn = %s)\n",
osmo_hexdump(vec->autn, sizeof(vec->autn)));
} else
LOGPC(DMM, LOGL_INFO, ")\n");
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_AUTH_CIPH_REQ;
acreq = (struct gsm48_auth_ciph_req *) msgb_put(msg, sizeof(*acreq));
acreq->ciph_alg = mm->ciph_algo & 0xf;
/* § 10.5.5.10: */
acreq->imeisv_req = 0x1;
/* § 10.5.5.7: */
acreq->force_stby = force_standby;
/* 3GPP TS 24.008 § 10.5.5.19: */
if (RAND_bytes(&rbyte, 1) != 1) {
LOGP(DMM, LOGL_NOTICE, "RAND_bytes failed for A&C ref, falling "
"back to rand()\n");
acreq->ac_ref_nr = rand();
} else
acreq->ac_ref_nr = rbyte;
mm->ac_ref_nr_used = acreq->ac_ref_nr;
/* Only if authentication is requested we need to set RAND + CKSN */
if (vec) {
m_rand = msgb_put(msg, sizeof(vec->rand) + 1);
m_rand[0] = GSM48_IE_GMM_AUTH_RAND;
memcpy(m_rand + 1, vec->rand, sizeof(vec->rand));
/* § 10.5.1.2: */
m_cksn = msgb_put(msg, 1);
m_cksn[0] = (GSM48_IE_GMM_CIPH_CKSN << 4) | (key_seq & 0x07);
/* A Release99 or higher MS/UE must be able to handle
* the optional AUTN IE. If a classic GSM SIM is
* inserted, it will simply ignore AUTN and just use
* RAND */
if (mmctx_is_r99(mm) &&
(vec->auth_types & OSMO_AUTH_TYPE_UMTS)) {
msgb_tlv_put(msg, GSM48_IE_GMM_AUTN,
sizeof(vec->autn), vec->autn);
}
}
return gsm48_gmm_sendmsg(msg, 1, mm, false);
}
/* Section 9.4.11: Authentication and Ciphering Reject */
static int gsm48_tx_gmm_auth_ciph_rej(struct sgsn_mm_ctx *mm)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 AUTH CIPH REJ");
struct gsm48_hdr *gh;
LOGMMCTXP(LOGL_NOTICE, mm, "<- GPRS AUTH AND CIPH REJECT\n");
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_AUTH_CIPH_REJ;
return gsm48_gmm_sendmsg(msg, 0, mm, false);
}
/* check if the received authentication response matches */
static bool check_auth_resp(struct sgsn_mm_ctx *ctx,
bool is_utran,
const struct osmo_auth_vector *vec,
const uint8_t *res, uint8_t res_len)
{
const uint8_t *expect_res;
uint8_t expect_res_len;
enum osmo_sub_auth_type expect_type;
const char *expect_str;
if (!vec)
return true; /* really!? */
/* On UTRAN (3G) we always expect UMTS AKA. On GERAN (2G) we sent AUTN
* and expect UMTS AKA if there is R99 capability and our vector
* supports UMTS AKA, otherwise we expect GSM AKA. */
if (is_utran
|| (mmctx_is_r99(ctx) && (vec->auth_types & OSMO_AUTH_TYPE_UMTS))) {
expect_type = OSMO_AUTH_TYPE_UMTS;
expect_str = "UMTS RES";
expect_res = vec->res;
expect_res_len = vec->res_len;
} else {
expect_type = OSMO_AUTH_TYPE_GSM;
expect_str = "GSM SRES";
expect_res = vec->sres;
expect_res_len = sizeof(vec->sres);
}
if (!(vec->auth_types & expect_type)) {
LOGMMCTXP(LOGL_ERROR, ctx, "Auth error: auth vector does"
" not provide the expected auth type:"
" expected %s = 0x%x, auth_types are 0x%x\n",
expect_str, expect_type, vec->auth_types);
return false;
}
if (!res)
goto auth_mismatch;
if (res_len != expect_res_len)
goto auth_mismatch;
if (memcmp(res, expect_res, res_len) != 0)
goto auth_mismatch;
/* Authorized! */
return true;
auth_mismatch:
LOGMMCTXP(LOGL_ERROR, ctx, "Auth mismatch: expected %s = %s\n",
expect_str, osmo_hexdump_nospc(expect_res, expect_res_len));
return false;
}
/* Section 9.4.10: Authentication and Ciphering Response */
static int gsm48_rx_gmm_auth_ciph_resp(struct sgsn_mm_ctx *ctx,
struct msgb *msg)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
struct gsm48_auth_ciph_resp *acr = (struct gsm48_auth_ciph_resp *)gh->data;
struct tlv_parsed tp;
struct gsm_auth_tuple *at;
const char *res_name = "(no response)";
uint8_t res[16];
uint8_t res_len;
int rc;
LOGMMCTXP(LOGL_INFO, ctx, "-> GPRS AUTH AND CIPH RESPONSE\n");
if (ctx->auth_triplet.key_seq == GSM_KEY_SEQ_INVAL) {
LOGMMCTXP(LOGL_NOTICE, ctx,
"Unexpected Auth & Ciph Response (ignored)\n");
return 0;
}
if (acr->ac_ref_nr != ctx->ac_ref_nr_used) {
LOGMMCTXP(LOGL_NOTICE, ctx, "Reference mismatch for Auth & Ciph"
" Response: %u received, %u expected\n",
acr->ac_ref_nr, ctx->ac_ref_nr_used);
return 0;
}
/* Stop T3360 */
mmctx_timer_stop(ctx, 3360);
tlv_parse(&tp, &gsm48_gmm_att_tlvdef, acr->data,
(msg->data + msg->len) - acr->data, 0, 0);
if (!TLVP_PRESENT(&tp, GSM48_IE_GMM_AUTH_SRES) ||
!TLVP_PRESENT(&tp, GSM48_IE_GMM_IMEISV) ||
TLVP_LEN(&tp,GSM48_IE_GMM_AUTH_SRES) != 4) {
/* TODO: missing mandatory IE, return STATUS or REJ? */
LOGMMCTXP(LOGL_ERROR, ctx, "Missing mandantory IE\n");
return -EINVAL;
}
/* Start with the good old 4-byte SRES */
memcpy(res, TLVP_VAL(&tp, GSM48_IE_GMM_AUTH_SRES), 4);
res_len = 4;
res_name = "GSM SRES";
/* Append extended RES as part of UMTS AKA, if any */
if (TLVP_PRESENT(&tp, GSM48_IE_GMM_AUTH_RES_EXT)) {
unsigned int l = TLVP_LEN(&tp, GSM48_IE_GMM_AUTH_RES_EXT);
if (l > sizeof(res)-4)
l = sizeof(res)-4;
memcpy(res+4, TLVP_VAL(&tp, GSM48_IE_GMM_AUTH_RES_EXT), l);
res_len += l;
res_name = "UMTS RES";
}
at = &ctx->auth_triplet;
LOGMMCTXP(LOGL_DEBUG, ctx, "checking auth: received %s = %s\n",
res_name, osmo_hexdump(res, res_len));
rc = check_auth_resp(ctx, false, &at->vec, res, res_len);
if (!rc) {
rc = gsm48_tx_gmm_auth_ciph_rej(ctx);
mm_ctx_cleanup_free(ctx, "GPRS AUTH AND CIPH REJECT");
return rc;
}
ctx->is_authenticated = 1;
if (ctx->ran_type == MM_CTX_T_UTRAN_Iu)
ctx->iu.new_key = 1;
/* FIXME: enable LLC cipheirng */
/* Check if we can let the mobile station enter */
return gsm48_gmm_authorize(ctx);
}
/* Section 9.4.10: Authentication and Ciphering Failure */
static int gsm48_rx_gmm_auth_ciph_fail(struct sgsn_mm_ctx *ctx,
struct msgb *msg)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
struct tlv_parsed tp;
const uint8_t gmm_cause = gh->data[0];
const uint8_t *auts;
int rc;
LOGMMCTXP(LOGL_INFO, ctx, "-> GPRS AUTH AND CIPH FAILURE (cause = %s)\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause));
tlv_parse(&tp, &gsm48_gmm_att_tlvdef, gh->data+1, msg->len - 1, 0, 0);
/* Only if GMM cause is present and the AUTS is provided, we can
* start re-sync procedure */
if (gmm_cause == GMM_CAUSE_SYNC_FAIL &&
TLVP_PRESENT(&tp, GSM48_IE_GMM_AUTH_FAIL_PAR)) {
if (TLVP_LEN(&tp, GSM48_IE_GMM_AUTH_FAIL_PAR) != 14) {
LOGMMCTXP(LOGL_ERROR, ctx, "AUTS IE has wrong size:"
" expected %d, got %u\n", 14,
TLVP_LEN(&tp, GSM48_IE_GMM_AUTH_FAIL_PAR));
return -EINVAL;
}
auts = TLVP_VAL(&tp, GSM48_IE_GMM_AUTH_FAIL_PAR);
LOGMMCTXP(LOGL_INFO, ctx,
"R99 AUTHENTICATION SYNCH (AUTS = %s)\n",
osmo_hexdump_nospc(auts, 14));
/* make sure we'll refresh the auth_triplet in
* sgsn_auth_update() */
ctx->auth_triplet.key_seq = GSM_KEY_SEQ_INVAL;
/* make sure we'll retry authentication after the resync */
ctx->auth_state = SGSN_AUTH_UMTS_RESYNC;
/* Send AUTS to HLR and wait for new Auth Info Result */
rc = gprs_subscr_request_auth_info(ctx, auts,
ctx->auth_triplet.vec.rand);
if (!rc)
return 0;
/* on error, fall through to send a reject */
LOGMMCTXP(LOGL_ERROR, ctx,
"Sending AUTS to HLR failed (rc = %d)\n", rc);
}
LOGMMCTXP(LOGL_NOTICE, ctx, "Authentication failed\n");
rc = gsm48_tx_gmm_auth_ciph_rej(ctx);
mm_ctx_cleanup_free(ctx, "GPRS AUTH FAILURE");
return rc;
}
static void extract_subscr_msisdn(struct sgsn_mm_ctx *ctx)
{
struct gsm_mncc_number called;
uint8_t msisdn[sizeof(ctx->subscr->sgsn_data->msisdn) + 1];
/* Convert MSISDN from encoded to string.. */
if (!ctx->subscr)
return;
if (ctx->subscr->sgsn_data->msisdn_len < 1)
return;
/* prepare the data for the decoder */
memset(&called, 0, sizeof(called));
msisdn[0] = ctx->subscr->sgsn_data->msisdn_len;
memcpy(&msisdn[1], ctx->subscr->sgsn_data->msisdn,
ctx->subscr->sgsn_data->msisdn_len);
/* decode the string now */
gsm48_decode_called(&called, msisdn);
/* Prepend a '+' for international numbers */
if (called.plan == 1 && called.type == 1) {
ctx->msisdn[0] = '+';
osmo_strlcpy(&ctx->msisdn[1], called.number,
sizeof(ctx->msisdn));
} else {
osmo_strlcpy(ctx->msisdn, called.number, sizeof(ctx->msisdn));
}
}
static void extract_subscr_hlr(struct sgsn_mm_ctx *ctx)
{
struct gsm_mncc_number called;
uint8_t hlr_number[sizeof(ctx->subscr->sgsn_data->hlr) + 1];
if (!ctx->subscr)
return;
if (ctx->subscr->sgsn_data->hlr_len < 1)
return;
/* prepare the data for the decoder */
memset(&called, 0, sizeof(called));
hlr_number[0] = ctx->subscr->sgsn_data->hlr_len;
memcpy(&hlr_number[1], ctx->subscr->sgsn_data->hlr,
ctx->subscr->sgsn_data->hlr_len);
/* decode the string now */
gsm48_decode_called(&called, hlr_number);
if (called.plan != 1) {
LOGMMCTXP(LOGL_ERROR, ctx,
"Numbering plan(%d) not allowed\n",
called.plan);
return;
}
if (called.type != 1) {
LOGMMCTXP(LOGL_ERROR, ctx,
"Numbering type(%d) not allowed\n",
called.type);
return;
}
osmo_strlcpy(ctx->hlr, called.number, sizeof(ctx->hlr));
}
#ifdef BUILD_IU
/* Chapter 9.4.21: Service accept */
static int gsm48_tx_gmm_service_ack(struct sgsn_mm_ctx *mm)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 SERVICE ACK");
struct gsm48_hdr *gh;
LOGMMCTXP(LOGL_INFO, mm, "<- GPRS SERVICE ACCEPT (P-TMSI=0x%08x)\n", mm->p_tmsi);
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_SERVICE_ACK;
/* Optional: PDP context status */
/* Optional: MBMS context status */
return gsm48_gmm_sendmsg(msg, 0, mm, false);
}
#endif
/* Chapter 9.4.22: Service reject */
static int _tx_gmm_service_rej(struct msgb *msg, uint8_t gmm_cause,
const struct sgsn_mm_ctx *mm)
{
struct gsm48_hdr *gh;
LOGMMCTXP(LOGL_NOTICE, mm, "<- GPRS SERVICE REJECT: %s\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause));
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_SERVICE_REJ;
gh->data[0] = gmm_cause;
return gsm48_gmm_sendmsg(msg, 0, NULL, true);
}
static int gsm48_tx_gmm_service_rej_oldmsg(const struct msgb *old_msg,
uint8_t gmm_cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 SERVICE REJ OLD");
gmm_copy_id(msg, old_msg);
return _tx_gmm_service_rej(msg, gmm_cause, NULL);
}
#if 0
-- currently unused --
static int gsm48_tx_gmm_service_rej(struct sgsn_mm_ctx *mm,
uint8_t gmm_cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 SERVICE REJ");
mmctx2msgid(msg, mm);
return _tx_gmm_service_rej(msg, gmm_cause, mm);
}
#endif
static int gsm48_tx_gmm_ra_upd_ack(struct sgsn_mm_ctx *mm);
#ifdef BUILD_IU
void activate_pdp_rabs(struct sgsn_mm_ctx *ctx)
{
/* Send RAB activation requests for all PDP contexts */
struct sgsn_pdp_ctx *pdp;
llist_for_each_entry(pdp, &ctx->pdp_list, list) {
iu_rab_act_ps(pdp->nsapi, pdp, 1);
}
}
#endif
/* Check if we can already authorize a subscriber */
static int gsm48_gmm_authorize(struct sgsn_mm_ctx *ctx)
{
#ifdef BUILD_IU
int rc;
#endif
#ifndef PTMSI_ALLOC
struct sgsn_signal_data sig_data;
#endif
/* Request IMSI and IMEI from the MS if they are unknown */
if (!strlen(ctx->imei)) {
ctx->t3370_id_type = GSM_MI_TYPE_IMEI;
mmctx_timer_start(ctx, 3370, sgsn->cfg.timers.T3370);
return gsm48_tx_gmm_id_req(ctx, GSM_MI_TYPE_IMEI);
}
if (!strlen(ctx->imsi)) {
ctx->t3370_id_type = GSM_MI_TYPE_IMSI;
mmctx_timer_start(ctx, 3370, sgsn->cfg.timers.T3370);
return gsm48_tx_gmm_id_req(ctx, GSM_MI_TYPE_IMSI);
}
/* All information required for authentication is available */
ctx->t3370_id_type = GSM_MI_TYPE_NONE;
if (ctx->auth_state == SGSN_AUTH_UNKNOWN) {
/* Request authorization, this leads to a call to
* sgsn_auth_update which in turn calls
* gsm0408_gprs_access_granted or gsm0408_gprs_access_denied */
sgsn_auth_request(ctx);
/* Note that gsm48_gmm_authorize can be called recursively via
* sgsn_auth_request iff ctx->auth_info changes to AUTH_ACCEPTED
*/
return 0;
}
if (ctx->auth_state == SGSN_AUTH_AUTHENTICATE && !ctx->is_authenticated) {
struct gsm_auth_tuple *at = &ctx->auth_triplet;
mmctx_timer_start(ctx, 3360, sgsn->cfg.timers.T3360);
return gsm48_tx_gmm_auth_ciph_req(ctx, &at->vec, at->key_seq,
false);
}
if (ctx->auth_state == SGSN_AUTH_AUTHENTICATE && ctx->is_authenticated &&
ctx->auth_triplet.key_seq != GSM_KEY_SEQ_INVAL) {
/* Check again for authorization */
sgsn_auth_request(ctx);
return 0;
}
if (ctx->auth_state != SGSN_AUTH_ACCEPTED) {
LOGMMCTXP(LOGL_NOTICE, ctx,
"authorization is denied, aborting procedure\n");
return -EACCES;
}
/* The MS is authorized */
#ifdef BUILD_IU
if (ctx->ran_type == MM_CTX_T_UTRAN_Iu && !ctx->iu.ue_ctx->integrity_active) {
rc = iu_tx_sec_mode_cmd(ctx->iu.ue_ctx, &ctx->auth_triplet, 0, ctx->iu.new_key);
ctx->iu.new_key = 0;
return rc;
}
#endif
switch (ctx->pending_req) {
case 0:
LOGMMCTXP(LOGL_INFO, ctx,
"no pending request, authorization completed\n");
break;
case GSM48_MT_GMM_ATTACH_REQ:
ctx->pending_req = 0;
extract_subscr_msisdn(ctx);
extract_subscr_hlr(ctx);
#ifdef PTMSI_ALLOC
/* Start T3350 and re-transmit up to 5 times until ATTACH COMPLETE */
mmctx_timer_start(ctx, 3350, sgsn->cfg.timers.T3350);
ctx->t3350_mode = GMM_T3350_MODE_ATT;
#else
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = mmctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_ATTACH, &sig_data);
ctx->gmm_state = GMM_REGISTERED_NORMAL;
#endif
return gsm48_tx_gmm_att_ack(ctx);
#ifdef BUILD_IU
case GSM48_MT_GMM_SERVICE_REQ:
ctx->pending_req = 0;
mmctx_set_pmm_state(ctx, PMM_CONNECTED);
rc = gsm48_tx_gmm_service_ack(ctx);
if (ctx->iu.service.type != GPRS_SERVICE_T_SIGNALLING)
activate_pdp_rabs(ctx);
return rc;
#endif
case GSM48_MT_GMM_RA_UPD_REQ:
ctx->pending_req = 0;
/* Send RA UPDATE ACCEPT */
return gsm48_tx_gmm_ra_upd_ack(ctx);
default:
LOGMMCTXP(LOGL_ERROR, ctx,
"only Attach Request is supported yet, "
"got request type %u\n", ctx->pending_req);
break;
}
return 0;
}
void gsm0408_gprs_authenticate(struct sgsn_mm_ctx *ctx)
{
ctx->is_authenticated = 0;
gsm48_gmm_authorize(ctx);
}
void gsm0408_gprs_access_granted(struct sgsn_mm_ctx *ctx)
{
switch (ctx->gmm_state) {
case GMM_COMMON_PROC_INIT:
LOGMMCTXP(LOGL_NOTICE, ctx,
"Authorized, continuing procedure, IMSI=%s\n",
ctx->imsi);
/* Continue with the authorization */
gsm48_gmm_authorize(ctx);
break;
default:
LOGMMCTXP(LOGL_INFO, ctx,
"Authorized, ignored, IMSI=%s\n",
ctx->imsi);
}
}
void gsm0408_gprs_access_denied(struct sgsn_mm_ctx *ctx, int gmm_cause)
{
if (gmm_cause == SGSN_ERROR_CAUSE_NONE)
gmm_cause = GMM_CAUSE_GPRS_NOTALLOWED;
switch (ctx->gmm_state) {
case GMM_COMMON_PROC_INIT:
LOGMMCTXP(LOGL_NOTICE, ctx,
"Not authorized, rejecting ATTACH REQUEST "
"with cause '%s' (%d)\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause),
gmm_cause);
gsm48_tx_gmm_att_rej(ctx, gmm_cause);
mm_ctx_cleanup_free(ctx, "GPRS ATTACH REJECT");
break;
case GMM_REGISTERED_NORMAL:
case GMM_REGISTERED_SUSPENDED:
LOGMMCTXP(LOGL_NOTICE, ctx,
"Authorization lost, detaching "
"with cause '%s' (%d)\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause),
gmm_cause);
gsm48_tx_gmm_detach_req(
ctx, GPRS_DET_T_MT_REATT_NOTREQ, gmm_cause);
mm_ctx_cleanup_free(ctx, "auth lost");
break;
default:
LOGMMCTXP(LOGL_INFO, ctx,
"Authorization lost, cause is '%s' (%d)\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause),
gmm_cause);
mm_ctx_cleanup_free(ctx, "auth lost");
}
}
void gsm0408_gprs_access_cancelled(struct sgsn_mm_ctx *ctx, int gmm_cause)
{
if (gmm_cause != SGSN_ERROR_CAUSE_NONE) {
LOGMMCTXP(LOGL_INFO, ctx,
"Cancelled with cause '%s' (%d), deleting context\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause),
gmm_cause);
gsm0408_gprs_access_denied(ctx, gmm_cause);
return;
}
LOGMMCTXP(LOGL_INFO, ctx, "Cancelled, deleting context silently\n");
mm_ctx_cleanup_free(ctx, "access cancelled");
}
/* Parse Chapter 9.4.13 Identity Response */
static int gsm48_rx_gmm_id_resp(struct sgsn_mm_ctx *ctx, struct msgb *msg)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t mi_type = gh->data[1] & GSM_MI_TYPE_MASK;
char mi_string[GSM48_MI_SIZE];
gsm48_mi_to_string(mi_string, sizeof(mi_string), &gh->data[1], gh->data[0]);
if (!ctx) {
DEBUGP(DMM, "from unknown TLLI 0x%08x?!? This should not happen\n", msgb_tlli(msg));
return -EINVAL;
}
LOGMMCTXP(LOGL_DEBUG, ctx, "-> GMM IDENTITY RESPONSE: MI(%s)=%s\n",
gsm48_mi_type_name(mi_type), mi_string);
if (ctx->t3370_id_type == GSM_MI_TYPE_NONE) {
LOGMMCTXP(LOGL_NOTICE, ctx,
"Got unexpected IDENTITY RESPONSE: MI(%s)=%s, "
"ignoring message\n",
gsm48_mi_type_name(mi_type), mi_string);
return -EINVAL;
}
if (mi_type == ctx->t3370_id_type)
mmctx_timer_stop(ctx, 3370);
switch (mi_type) {
case GSM_MI_TYPE_IMSI:
/* we already have a mm context with current TLLI, but no
* P-TMSI / IMSI yet. What we now need to do is to fill
* this initial context with data from the HLR */
if (strlen(ctx->imsi) == 0) {
/* Check if we already have a MM context for this IMSI */
struct sgsn_mm_ctx *ictx;
ictx = sgsn_mm_ctx_by_imsi(mi_string);
if (ictx) {
/* Handle it like in gsm48_rx_gmm_det_req,
* except that no messages are sent to the BSS */
LOGMMCTXP(LOGL_NOTICE, ctx, "Deleting old MM Context for same IMSI "
"p_tmsi_old=0x%08x\n",
ictx->p_tmsi);
mm_ctx_cleanup_free(ictx, "GPRS IMSI re-use");
}
}
osmo_strlcpy(ctx->imsi, mi_string, sizeof(ctx->imsi));
break;
case GSM_MI_TYPE_IMEI:
osmo_strlcpy(ctx->imei, mi_string, sizeof(ctx->imei));
break;
case GSM_MI_TYPE_IMEISV:
break;
}
/* Check if we can let the mobile station enter */
return gsm48_gmm_authorize(ctx);
}
/* Section 9.4.1 Attach request */
static int gsm48_rx_gmm_att_req(struct sgsn_mm_ctx *ctx, struct msgb *msg,
struct gprs_llc_llme *llme)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t *cur = gh->data, *msnc, *mi, *ms_ra_acc_cap;
uint8_t msnc_len, att_type, mi_len, mi_type, ms_ra_acc_cap_len;
uint16_t drx_par;
uint32_t tmsi;
char mi_string[GSM48_MI_SIZE];
struct gprs_ra_id ra_id;
uint16_t cid = 0;
enum gsm48_gmm_cause reject_cause;
int rc;
LOGMMCTXP(LOGL_INFO, ctx, "-> GMM ATTACH REQUEST ");
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_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),
* or with random TLLI. */
/* In Iu mode, msg->dst contains the ue_conn_ctx pointer, in Gb mode
* dst is empty. */
/* FIXME: have a more explicit indicator for Iu messages */
if (!msg->dst) {
/* Gb mode */
cid = bssgp_parse_cell_id(&ra_id, msgb_bcid(msg));
} else
ra_id = ((struct ue_conn_ctx*)msg->dst)->ra_id;
/* MS network capability 10.5.5.12 */
msnc_len = *cur++;
msnc = cur;
if (msnc_len > sizeof(ctx->ms_network_capa.buf))
goto err_inval;
cur += msnc_len;
/* TODO: In iu mode - handle follow-on request */
/* aTTACH Type 10.5.5.2 */
att_type = *cur++ & 0x07;
/* DRX parameter 10.5.5.6 */
drx_par = *cur++ << 8;
drx_par |= *cur++;
/* Mobile Identity (P-TMSI or IMSI) 10.5.1.4 */
mi_len = *cur++;
mi = cur;
if (mi_len > 8)
goto err_inval;
mi_type = *mi & GSM_MI_TYPE_MASK;
cur += mi_len;
gsm48_mi_to_string(mi_string, sizeof(mi_string), mi, mi_len);
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. Skip it */
cur += 6;
/* MS Radio Access Capability 10.5.5.12a */
ms_ra_acc_cap_len = *cur++;
ms_ra_acc_cap = cur;
if (ms_ra_acc_cap_len > sizeof(ctx->ms_radio_access_capa.buf))
goto err_inval;
cur += ms_ra_acc_cap_len;
LOGPC(DMM, LOGL_INFO, "\n");
/* Optional: Old P-TMSI Signature, Requested READY timer, TMSI Status */
switch (mi_type) {
case GSM_MI_TYPE_IMSI:
/* Try to find MM context based on IMSI */
if (!ctx)
ctx = sgsn_mm_ctx_by_imsi(mi_string);
if (!ctx) {
#if 0
return gsm48_tx_gmm_att_rej(msg, GMM_CAUSE_IMSI_UNKNOWN);
#else
if (msg->dst)
ctx = sgsn_mm_ctx_alloc_iu(msg->dst);
else
ctx = sgsn_mm_ctx_alloc_gb(0, &ra_id);
if (!ctx) {
reject_cause = GMM_CAUSE_NET_FAIL;
goto rejected;
}
osmo_strlcpy(ctx->imsi, mi_string, sizeof(ctx->imsi));
#endif
}
if (ctx->ran_type == MM_CTX_T_GERAN_Gb) {
ctx->gb.tlli = msgb_tlli(msg);
ctx->gb.llme = llme;
}
msgid2mmctx(ctx, msg);
break;
case GSM_MI_TYPE_TMSI:
memcpy(&tmsi, mi+1, 4);
tmsi = ntohl(tmsi);
/* Try to find MM context based on P-TMSI */
if (!ctx)
ctx = sgsn_mm_ctx_by_ptmsi(tmsi);
if (!ctx) {
/* Allocate a context as most of our code expects one.
* Context will not have an IMSI ultil ID RESP is received */
if (msg->dst)
ctx = sgsn_mm_ctx_alloc_iu(msg->dst);
else
ctx = sgsn_mm_ctx_alloc_gb(msgb_tlli(msg), &ra_id);
ctx->p_tmsi = tmsi;
}
if (ctx->ran_type == MM_CTX_T_GERAN_Gb) {
ctx->gb.tlli = msgb_tlli(msg);
ctx->gb.llme = llme;
}
msgid2mmctx(ctx, msg);
break;
default:
LOGMMCTXP(LOGL_NOTICE, ctx, "Rejecting ATTACH REQUEST with "
"MI type %s\n", gsm48_mi_type_name(mi_type));
reject_cause = GMM_CAUSE_MS_ID_NOT_DERIVED;
goto rejected;
}
/* Update MM Context with currient RA and Cell ID */
ctx->ra = ra_id;
if (ctx->ran_type == MM_CTX_T_GERAN_Gb)
ctx->gb.cell_id = cid;
else if (ctx->ran_type == MM_CTX_T_UTRAN_Iu) {
/* DEVELOPMENT HACK: Our current HLR does not support 3G
* authentication tokens. A new HLR/VLR implementation is being
* developed. Until it is ready and actual milenage
* authentication is properly supported, we are hardcoding a
* fixed Ki and use 2G auth. */
unsigned char tmp_rand[16];
/* Ki 000102030405060708090a0b0c0d0e0f */
struct osmo_sub_auth_data auth = {
.type = OSMO_AUTH_TYPE_GSM,
.algo = OSMO_AUTH_ALG_COMP128v1,
.u.gsm.ki = {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d,
0x0e, 0x0f
},
};
/* XXX: Hack to make 3G auth work with special SIM card */
ctx->auth_state = SGSN_AUTH_AUTHENTICATE;
RAND_bytes(tmp_rand, 16);
memset(&ctx->auth_triplet.vec, 0, sizeof(ctx->auth_triplet.vec));
osmo_auth_gen_vec(&ctx->auth_triplet.vec, &auth, tmp_rand);
ctx->auth_triplet.key_seq = 0;
}
/* Update MM Context with other data */
ctx->drx_parms = drx_par;
ctx->ms_radio_access_capa.len = ms_ra_acc_cap_len;
memcpy(ctx->ms_radio_access_capa.buf, ms_ra_acc_cap,
ctx->ms_radio_access_capa.len);
ctx->ms_network_capa.len = msnc_len;
memcpy(ctx->ms_network_capa.buf, msnc, msnc_len);
if (!gprs_ms_net_cap_gea_supported(ctx->ms_network_capa.buf, msnc_len,
ctx->ciph_algo)) {
reject_cause = GMM_CAUSE_PROTO_ERR_UNSPEC;
LOGMMCTXP(LOGL_NOTICE, ctx, "Rejecting ATTACH REQUEST with MI "
"type %s because MS do not support required %s "
"encryption\n", gsm48_mi_type_name(mi_type),
get_value_string(gprs_cipher_names,ctx->ciph_algo));
goto rejected;
}
#ifdef PTMSI_ALLOC
/* Allocate a new P-TMSI (+ P-TMSI signature) and update TLLI */
/* Don't change the P-TMSI if a P-TMSI re-assignment is under way */
if (ctx->gmm_state != GMM_COMMON_PROC_INIT) {
ctx->p_tmsi_old = ctx->p_tmsi;
ctx->p_tmsi = sgsn_alloc_ptmsi();
}
ctx->gmm_state = GMM_COMMON_PROC_INIT;
#endif
if (ctx->ran_type == MM_CTX_T_GERAN_Gb) {
/* Even if there is no P-TMSI allocated, the MS will
* switch from foreign TLLI to local TLLI */
ctx->gb.tlli_new = gprs_tmsi2tlli(ctx->p_tmsi, TLLI_LOCAL);
/* Inform LLC layer about new TLLI but keep old active */
if (ctx->is_authenticated)
gprs_llme_copy_key(ctx, ctx->gb.llme);
gprs_llgmm_assign(ctx->gb.llme, ctx->gb.tlli, ctx->gb.tlli_new);
}
ctx->pending_req = GSM48_MT_GMM_ATTACH_REQ;
return gsm48_gmm_authorize(ctx);
err_inval:
LOGPC(DMM, LOGL_INFO, "\n");
reject_cause = GMM_CAUSE_SEM_INCORR_MSG;
rejected:
/* Send ATTACH REJECT */
LOGMMCTXP(LOGL_NOTICE, ctx,
"Rejecting Attach Request with cause '%s' (%d)\n",
get_value_string(gsm48_gmm_cause_names, reject_cause), reject_cause);
rc = gsm48_tx_gmm_att_rej_oldmsg(msg, reject_cause);
if (ctx)
mm_ctx_cleanup_free(ctx, "GPRS ATTACH REJ");
else
gprs_llgmm_unassign(llme);
return rc;
}
/* Section 4.7.4.1 / 9.4.5.2 MO Detach request */
static int gsm48_rx_gmm_det_req(struct sgsn_mm_ctx *ctx, struct msgb *msg)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t detach_type, power_off;
int rc = 0;
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 */
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_DETACH_REQUEST]);
LOGMMCTXP(LOGL_INFO, ctx, "-> 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" : "");
/* Only send the Detach Accept (MO) if power off isn't indicated,
* see 04.08, 4.7.4.1.2/3 for details */
if (!power_off) {
/* force_stby = 0 */
if (ctx)
rc = gsm48_tx_gmm_det_ack(ctx, 0);
else
rc = gsm48_tx_gmm_det_ack_oldmsg(msg, 0);
}
if (ctx) {
struct sgsn_signal_data sig_data;
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = ctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_DETACH, &sig_data);
mm_ctx_cleanup_free(ctx, "GPRS DETACH REQUEST");
}
return rc;
}
/* Chapter 9.4.15: Routing area update accept */
static int gsm48_tx_gmm_ra_upd_ack(struct sgsn_mm_ctx *mm)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 UPD ACK");
struct gsm48_hdr *gh;
struct gsm48_ra_upd_ack *rua;
uint8_t *mid;
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_ROUTING_AREA_ACKED]);
LOGMMCTXP(LOGL_INFO, mm, "<- ROUTING AREA UPDATE ACCEPT\n");
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_RA_UPD_ACK;
rua = (struct gsm48_ra_upd_ack *) msgb_put(msg, sizeof(*rua));
rua->force_stby = 0; /* not indicated */
rua->upd_result = 0; /* RA updated */
rua->ra_upd_timer = gprs_secs_to_tmr_floor(sgsn->cfg.timers.T3312);
gsm48_construct_ra(rua->ra_id.digits, &mm->ra);
#if 0
/* Optional: P-TMSI signature */
msgb_v_put(msg, GSM48_IE_GMM_PTMSI_SIG);
ptsig = msgb_put(msg, 3);
ptsig[0] = mm->p_tmsi_sig >> 16;
ptsig[1] = mm->p_tmsi_sig >> 8;
ptsig[2] = mm->p_tmsi_sig & 0xff;
#endif
#ifdef PTMSI_ALLOC
/* Optional: Allocated P-TMSI */
mid = msgb_put(msg, GSM48_MID_TMSI_LEN);
gsm48_generate_mid_from_tmsi(mid, mm->p_tmsi);
mid[0] = GSM48_IE_GMM_ALLOC_PTMSI;
#endif
/* Optional: Negotiated READY timer value */
msgb_tv_put(msg, GSM48_IE_GMM_TIMER_READY,
gprs_secs_to_tmr_floor(sgsn->cfg.timers.T3314));
/* Option: MS ID, ... */
return gsm48_gmm_sendmsg(msg, 0, mm, true);
}
/* Chapter 9.4.17: Routing area update reject */
static int gsm48_tx_gmm_ra_upd_rej(struct msgb *old_msg, uint8_t cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 RA UPD REJ");
struct gsm48_hdr *gh;
LOGP(DMM, LOGL_NOTICE, "<- ROUTING AREA UPDATE REJECT\n");
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_ROUTING_AREA_REJECT]);
gmm_copy_id(msg, old_msg);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 2);
gh->proto_discr = GSM48_PDISC_MM_GPRS;
gh->msg_type = GSM48_MT_GMM_RA_UPD_REJ;
gh->data[0] = cause;
gh->data[1] = 0; /* ? */
/* Option: P-TMSI signature, allocated P-TMSI, MS ID, ... */
return gsm48_gmm_sendmsg(msg, 0, NULL, false);
}
static void process_ms_ctx_status(struct sgsn_mm_ctx *mmctx,
const uint8_t *pdp_status)
{
struct sgsn_pdp_ctx *pdp, *pdp2;
/* 24.008 4.7.5.1.3: If the PDP context status information element is
* included in ROUTING AREA UPDATE REQUEST message, then the network
* shall deactivate all those PDP contexts locally (without peer to
* peer signalling between the MS and the network), which are not in SM
* state PDP-INACTIVE on network side but are indicated by the MS as
* being in state PDP-INACTIVE. */
llist_for_each_entry_safe(pdp, pdp2, &mmctx->pdp_list, list) {
if (pdp->nsapi < 8) {
if (!(pdp_status[0] & (1 << pdp->nsapi))) {
LOGMMCTXP(LOGL_NOTICE, mmctx, "Dropping PDP context for NSAPI=%u "
"due to PDP CTX STATUS IE= 0x%02x%02x\n",
pdp->nsapi, pdp_status[1], pdp_status[0]);
sgsn_delete_pdp_ctx(pdp);
}
} else {
if (!(pdp_status[1] & (1 << (pdp->nsapi - 8)))) {
LOGMMCTXP(LOGL_NOTICE, mmctx, "Dropping PDP context for NSAPI=%u "
"due to PDP CTX STATUS IE= 0x%02x%02x\n",
pdp->nsapi, pdp_status[1], pdp_status[0]);
sgsn_delete_pdp_ctx(pdp);
}
}
}
}
/* Chapter 9.4.14: Routing area update request */
static int gsm48_rx_gmm_ra_upd_req(struct sgsn_mm_ctx *mmctx, struct msgb *msg,
struct gprs_llc_llme *llme)
{
#ifndef PTMSI_ALLOC
struct sgsn_signal_data sig_data;
#endif
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t *cur = gh->data;
uint8_t ms_ra_acc_cap_len;
struct gprs_ra_id old_ra_id;
struct tlv_parsed tp;
uint8_t upd_type;
enum gsm48_gmm_cause reject_cause = GMM_CAUSE_PROTO_ERR_UNSPEC;
int rc;
/* TODO: In iu mode - handle follow-on request */
/* Update Type 10.5.5.18 */
upd_type = *cur++ & 0x07;
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_GPRS_ROUTING_AREA_REQUEST]);
LOGP(DMM, LOGL_INFO, "-> GMM RA UPDATE REQUEST type=\"%s\"\n",
get_value_string(gprs_upd_t_strs, upd_type));
/* Old routing area identification 10.5.5.15 */
gsm48_parse_ra(&old_ra_id, cur);
cur += 6;
/* MS Radio Access Capability 10.5.5.12a */
ms_ra_acc_cap_len = *cur++;
if (ms_ra_acc_cap_len > 52) {
reject_cause = GMM_CAUSE_PROTO_ERR_UNSPEC;
goto rejected;
}
cur += ms_ra_acc_cap_len;
/* Optional: Old P-TMSI Signature, Requested READY timer, TMSI Status,
* DRX parameter, MS network capability */
tlv_parse(&tp, &gsm48_gmm_att_tlvdef, cur,
(msg->data + msg->len) - cur, 0, 0);
switch (upd_type) {
case GPRS_UPD_T_RA_LA:
case GPRS_UPD_T_RA_LA_IMSI_ATT:
LOGP(DMM, LOGL_NOTICE, "Update type %i unsupported in Mode III, is your SI13 corrupt?\n", upd_type);
reject_cause = GMM_CAUSE_PROTO_ERR_UNSPEC;
goto rejected;
case GPRS_UPD_T_RA:
case GPRS_UPD_T_PERIODIC:
break;
}
if (!mmctx) {
/* BSSGP doesn't give us an mmctx */
/* TODO: Check if there is an MM CTX with old_ra_id and
* the P-TMSI (if given, reguired for UMTS) or as last resort
* if the TLLI matches foreign_tlli (P-TMSI). Note that this
* is an optimization to avoid the RA reject (impl detached)
* below, which will cause a new attach cycle. */
/* Look-up the MM context based on old RA-ID and TLLI */
/* In Iu mode, msg->dst contains the ue_conn_ctx pointer, in Gb
* mode dst is empty. */
/* FIXME: have a more explicit indicator for Iu messages */
if (!msg->dst) {
mmctx = sgsn_mm_ctx_by_tlli_and_ptmsi(msgb_tlli(msg), &old_ra_id);
} else if (TLVP_PRESENT(&tp, GSM48_IE_GMM_ALLOC_PTMSI)) {
#ifdef BUILD_IU
/* In Iu mode search only for ptmsi */
char mi_string[GSM48_MI_SIZE];
uint8_t mi_len = TLVP_LEN(&tp, GSM48_IE_GMM_ALLOC_PTMSI);
uint8_t *mi = TLVP_VAL(&tp, GSM48_IE_GMM_ALLOC_PTMSI);
uint8_t mi_type = *mi & GSM_MI_TYPE_MASK;
uint32_t tmsi;
gsm48_mi_to_string(mi_string, sizeof(mi_string), mi, mi_len);
if (mi_type == GSM_MI_TYPE_TMSI) {
memcpy(&tmsi, mi+1, 4);
tmsi = ntohl(tmsi);
mmctx = sgsn_mm_ctx_by_ptmsi(tmsi);
}
#else
goto rejected;
#endif
}
if (mmctx) {
LOGMMCTXP(LOGL_INFO, mmctx,
"Looked up by matching TLLI and P_TMSI. "
"BSSGP TLLI: %08x, P-TMSI: %08x (%08x), "
"TLLI: %08x (%08x), RA: %d-%d-%d-%d\n",
msgb_tlli(msg),
mmctx->p_tmsi, mmctx->p_tmsi_old,
mmctx->gb.tlli, mmctx->gb.tlli_new,
mmctx->ra.mcc, mmctx->ra.mnc,
mmctx->ra.lac, mmctx->ra.rac);
mmctx->gmm_state = GMM_COMMON_PROC_INIT;
}
} else if (!gprs_ra_id_equals(&mmctx->ra, &old_ra_id) ||
mmctx->gmm_state == GMM_DEREGISTERED)
{
/* We cannot use the mmctx */
LOGMMCTXP(LOGL_INFO, mmctx,
"The MM context cannot be used, RA: %d-%d-%d-%d\n",
mmctx->ra.mcc, mmctx->ra.mnc,
mmctx->ra.lac, mmctx->ra.rac);
mmctx = NULL;
}
if (!mmctx) {
if (llme) {
/* send a XID reset to re-set all LLC sequence numbers
* in the MS */
LOGMMCTXP(LOGL_NOTICE, mmctx, "LLC XID RESET\n");
gprs_llgmm_reset(llme);
}
/* The MS has to perform GPRS attach */
/* Device is still IMSI attached for CS but initiate GPRS ATTACH,
* see GSM 04.08, 4.7.5.1.4 and G.6 */
reject_cause = GMM_CAUSE_IMPL_DETACHED;
goto rejected;
}
/* Store new BVCI/NSEI in MM context (FIXME: delay until we ack?) */
msgid2mmctx(mmctx, msg);
/* Bump the statistics of received signalling msgs for this MM context */
rate_ctr_inc(&mmctx->ctrg->ctr[GMM_CTR_PKTS_SIG_IN]);
/* Update the MM context with the new RA-ID */
if (mmctx->ran_type == MM_CTX_T_GERAN_Gb) {
bssgp_parse_cell_id(&mmctx->ra, msgb_bcid(msg));
/* Update the MM context with the new (i.e. foreign) TLLI */
mmctx->gb.tlli = msgb_tlli(msg);
}
/* FIXME: Update the MM context with the MS radio acc capabilities */
/* FIXME: Update the MM context with the MS network capabilities */
rate_ctr_inc(&mmctx->ctrg->ctr[GMM_CTR_RA_UPDATE]);
#ifdef PTMSI_ALLOC
/* Don't change the P-TMSI if a P-TMSI re-assignment is under way */
if (mmctx->gmm_state != GMM_COMMON_PROC_INIT) {
mmctx->p_tmsi_old = mmctx->p_tmsi;
mmctx->p_tmsi = sgsn_alloc_ptmsi();
}
/* Start T3350 and re-transmit up to 5 times until ATTACH COMPLETE */
mmctx->t3350_mode = GMM_T3350_MODE_RAU;
mmctx_timer_start(mmctx, 3350, sgsn->cfg.timers.T3350);
mmctx->gmm_state = GMM_COMMON_PROC_INIT;
#else
/* Make sure we are NORMAL (i.e. not SUSPENDED anymore) */
mmctx->gmm_state = GMM_REGISTERED_NORMAL;
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = mmctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_UPDATE, &sig_data);
#endif
if (mmctx->ran_type == MM_CTX_T_GERAN_Gb) {
/* Even if there is no P-TMSI allocated, the MS will switch from
* foreign TLLI to local TLLI */
mmctx->gb.tlli_new = gprs_tmsi2tlli(mmctx->p_tmsi, TLLI_LOCAL);
/* Inform LLC layer about new TLLI but keep old active */
gprs_llgmm_assign(mmctx->gb.llme, mmctx->gb.tlli,
mmctx->gb.tlli_new);
}
/* Look at PDP Context Status IE and see if MS's view of
* activated/deactivated NSAPIs agrees with our view */
if (TLVP_PRESENT(&tp, GSM48_IE_GMM_PDP_CTX_STATUS)) {
const uint8_t *pdp_status = TLVP_VAL(&tp, GSM48_IE_GMM_PDP_CTX_STATUS);
process_ms_ctx_status(mmctx, pdp_status);
}
/* Send RA UPDATE ACCEPT. In Iu, the RA upd request can be called from
* a new Iu connection, so we might need to re-authenticate the
* connection as well as turn on integrity protection. */
mmctx->pending_req = GSM48_MT_GMM_RA_UPD_REQ;
return gsm48_gmm_authorize(mmctx);
rejected:
/* Send RA UPDATE REJECT */
LOGMMCTXP(LOGL_NOTICE, mmctx,
"Rejecting RA Update Request with cause '%s' (%d)\n",
get_value_string(gsm48_gmm_cause_names, reject_cause), reject_cause);
rc = gsm48_tx_gmm_ra_upd_rej(msg, reject_cause);
if (mmctx)
mm_ctx_cleanup_free(mmctx, "GPRS RA UPDATE REJ");
else {
if (llme)
gprs_llgmm_unassign(llme);
}
return rc;
}
/* 3GPP TS 24.008 Section 9.4.20 Service request.
* In Iu, a UE in PMM-IDLE mode can use GSM48_MT_GMM_SERVICE_REQ to switch back
* to PMM-CONNECTED mode. */
static int gsm48_rx_gmm_service_req(struct sgsn_mm_ctx *ctx, struct msgb *msg)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t *cur = gh->data, *mi;
uint8_t ciph_seq_nr, service_type, mi_len, mi_type;
uint32_t tmsi;
struct tlv_parsed tp;
char mi_string[GSM48_MI_SIZE];
enum gsm48_gmm_cause reject_cause;
int rc;
LOGMMCTXP(LOGL_INFO, ctx, "-> GMM SERVICE REQUEST ");
/* This message is only valid in Iu mode */
if (!msg->dst) {
LOGPC(DMM, LOGL_INFO, "Invalid if not in Iu mode\n");
return -1;
}
/* Skip Ciphering key sequence number 10.5.1.2 */
ciph_seq_nr = *cur & 0x07;
/* Service type 10.5.5.20 */
service_type = (*cur++ >> 4) & 0x07;
/* Mobile Identity (P-TMSI or IMSI) 10.5.1.4 */
mi_len = *cur++;
mi = cur;
if (mi_len > 8)
goto err_inval;
mi_type = *mi & GSM_MI_TYPE_MASK;
cur += mi_len;
gsm48_mi_to_string(mi_string, sizeof(mi_string), mi, mi_len);
DEBUGPC(DMM, "MI(%s) type=\"%s\" ", mi_string,
get_value_string(gprs_service_t_strs, service_type));
LOGPC(DMM, LOGL_INFO, "\n");
/* Optional: PDP context status, MBMS context status, Uplink data status, Device properties */
tlv_parse(&tp, &gsm48_gmm_att_tlvdef, cur, (msg->data + msg->len) - cur, 0, 0);
switch (mi_type) {
case GSM_MI_TYPE_IMSI:
/* Try to find MM context based on IMSI */
if (!ctx)
ctx = sgsn_mm_ctx_by_imsi(mi_string);
if (!ctx) {
/* FIXME: We need to have a context for service request? */
reject_cause = GMM_CAUSE_NET_FAIL;
goto rejected;
}
msgid2mmctx(ctx, msg);
break;
case GSM_MI_TYPE_TMSI:
memcpy(&tmsi, mi+1, 4);
tmsi = ntohl(tmsi);
/* Try to find MM context based on P-TMSI */
if (!ctx)
ctx = sgsn_mm_ctx_by_ptmsi(tmsi);
if (!ctx) {
/* FIXME: We need to have a context for service request? */
reject_cause = GMM_CAUSE_NET_FAIL;
goto rejected;
}
msgid2mmctx(ctx, msg);
break;
default:
LOGMMCTXP(LOGL_NOTICE, ctx, "Rejecting SERVICE REQUEST with "
"MI type %s\n", gsm48_mi_type_name(mi_type));
reject_cause = GMM_CAUSE_MS_ID_NOT_DERIVED;
goto rejected;
}
ctx->gmm_state = GMM_COMMON_PROC_INIT;
ctx->iu.service.type = service_type;
/* TODO: Handle those only in case of accept? */
/* Look at PDP Context Status IE and see if MS's view of
* activated/deactivated NSAPIs agrees with our view */
if (TLVP_PRESENT(&tp, GSM48_IE_GMM_PDP_CTX_STATUS)) {
const uint8_t *pdp_status = TLVP_VAL(&tp, GSM48_IE_GMM_PDP_CTX_STATUS);
process_ms_ctx_status(ctx, pdp_status);
}
ctx->pending_req = GSM48_MT_GMM_SERVICE_REQ;
return gsm48_gmm_authorize(ctx);
err_inval:
LOGPC(DMM, LOGL_INFO, "\n");
reject_cause = GMM_CAUSE_SEM_INCORR_MSG;
rejected:
/* Send SERVICE REJECT */
LOGMMCTXP(LOGL_NOTICE, ctx,
"Rejecting Service Request with cause '%s' (%d)\n",
get_value_string(gsm48_gmm_cause_names, reject_cause), reject_cause);
rc = gsm48_tx_gmm_service_rej_oldmsg(msg, reject_cause);
return rc;
}
static int gsm48_rx_gmm_status(struct sgsn_mm_ctx *mmctx, struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
LOGMMCTXP(LOGL_INFO, mmctx, "-> GPRS MM STATUS (cause: %s)\n",
get_value_string(gsm48_gmm_cause_names, gh->data[0]));
return 0;
}
/* GPRS Mobility Management */
static int gsm0408_rcv_gmm(struct sgsn_mm_ctx *mmctx, struct msgb *msg,
struct gprs_llc_llme *llme, bool drop_cipherable)
{
struct sgsn_signal_data sig_data;
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
int rc;
/* MMCTX can be NULL when called */
if (drop_cipherable && gsm48_hdr_gmm_cipherable(gh)) {
LOGMMCTXP(LOGL_NOTICE, mmctx, "Dropping cleartext GMM %s which "
"is expected to be encrypted for TLLI 0x%08x\n",
get_value_string(gprs_msgt_gmm_names, gh->msg_type),
llme->tlli);
return -EBADMSG;
}
if (llme && !mmctx &&
gh->msg_type != GSM48_MT_GMM_ATTACH_REQ &&
gh->msg_type != GSM48_MT_GMM_RA_UPD_REQ) {
LOGP(DMM, LOGL_NOTICE, "Cannot handle GMM for unknown MM CTX\n");
/* 4.7.10 */
if (gh->msg_type == GSM48_MT_GMM_STATUS) {
/* TLLI unassignment */
gprs_llgmm_unassign(llme);
return 0;
}
/* Don't reply or establish a LLME on DETACH_ACK */
if (gh->msg_type == GSM48_MT_GMM_DETACH_ACK)
return gprs_llgmm_unassign(llme);
gprs_llgmm_reset(llme);
/* Don't force it into re-attachment */
if (gh->msg_type == GSM48_MT_GMM_DETACH_REQ) {
/* Handle Detach Request */
rc = gsm48_rx_gmm_det_req(NULL, msg);
/* TLLI unassignment */
gprs_llgmm_unassign(llme);
return rc;
}
/* Force the MS to re-attach */
rc = gsm0408_gprs_force_reattach_oldmsg(msg, llme);
/* TLLI unassignment */
gprs_llgmm_unassign(llme);
return rc;
}
/*
* For a few messages, mmctx may be NULL. For most, we want to ensure a
* non-NULL mmctx. At the same time, we want to keep the message
* validity check intact, so that all message types appear in the
* switch statement and the default case thus means "unknown message".
* If we split the switch in two parts to check non-NULL halfway, the
* unknown-message check breaks, or we'd need to duplicate the switch
* cases in both parts. Just keep one large switch and add some gotos.
*/
switch (gh->msg_type) {
case GSM48_MT_GMM_RA_UPD_REQ:
rc = gsm48_rx_gmm_ra_upd_req(mmctx, msg, llme);
break;
case GSM48_MT_GMM_ATTACH_REQ:
rc = gsm48_rx_gmm_att_req(mmctx, msg, llme);
break;
case GSM48_MT_GMM_SERVICE_REQ:
rc = gsm48_rx_gmm_service_req(mmctx, msg);
break;
/* For all the following types mmctx can not be NULL */
case GSM48_MT_GMM_ID_RESP:
if (!mmctx)
goto null_mmctx;
rc = gsm48_rx_gmm_id_resp(mmctx, msg);
break;
case GSM48_MT_GMM_STATUS:
if (!mmctx)
goto null_mmctx;
rc = gsm48_rx_gmm_status(mmctx, msg);
break;
case GSM48_MT_GMM_DETACH_REQ:
if (!mmctx)
goto null_mmctx;
rc = gsm48_rx_gmm_det_req(mmctx, msg);
break;
case GSM48_MT_GMM_DETACH_ACK:
if (!mmctx)
goto null_mmctx;
LOGMMCTXP(LOGL_INFO, mmctx, "-> DETACH ACK\n");
mm_ctx_cleanup_free(mmctx, "GPRS DETACH ACK");
rc = 0;
break;
case GSM48_MT_GMM_ATTACH_COMPL:
if (!mmctx)
goto null_mmctx;
/* only in case SGSN offered new P-TMSI */
LOGMMCTXP(LOGL_INFO, mmctx, "-> ATTACH COMPLETE\n");
mmctx_timer_stop(mmctx, 3350);
mmctx->t3350_mode = GMM_T3350_MODE_NONE;
mmctx->p_tmsi_old = 0;
mmctx->pending_req = 0;
if (mmctx->ran_type == MM_CTX_T_GERAN_Gb) {
/* Unassign the old TLLI */
mmctx->gb.tlli = mmctx->gb.tlli_new;
gprs_llme_copy_key(mmctx, mmctx->gb.llme);
gprs_llgmm_assign(mmctx->gb.llme, 0xffffffff,
mmctx->gb.tlli_new);
}
mmctx->gmm_state = GMM_REGISTERED_NORMAL;
mmctx_set_pmm_state(mmctx, PMM_CONNECTED);
mmctx_set_mm_state(mmctx, MM_READY);
rc = 0;
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = mmctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_ATTACH, &sig_data);
break;
case GSM48_MT_GMM_RA_UPD_COMPL:
if (!mmctx)
goto null_mmctx;
/* only in case SGSN offered new P-TMSI */
LOGMMCTXP(LOGL_INFO, mmctx, "-> ROUTING AREA UPDATE COMPLETE\n");
mmctx_timer_stop(mmctx, 3350);
mmctx->t3350_mode = GMM_T3350_MODE_NONE;
mmctx->p_tmsi_old = 0;
mmctx->pending_req = 0;
if (mmctx->ran_type == MM_CTX_T_GERAN_Gb) {
/* Unassign the old TLLI */
mmctx->gb.tlli = mmctx->gb.tlli_new;
gprs_llgmm_assign(mmctx->gb.llme, 0xffffffff,
mmctx->gb.tlli_new);
}
mmctx->gmm_state = GMM_REGISTERED_NORMAL;
mmctx_set_pmm_state(mmctx, PMM_CONNECTED);
mmctx_set_mm_state(mmctx, MM_READY);
rc = 0;
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = mmctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_UPDATE, &sig_data);
break;
case GSM48_MT_GMM_PTMSI_REALL_COMPL:
if (!mmctx)
goto null_mmctx;
LOGMMCTXP(LOGL_INFO, mmctx, "-> PTMSI REALLLICATION COMPLETE\n");
mmctx_timer_stop(mmctx, 3350);
mmctx->t3350_mode = GMM_T3350_MODE_NONE;
mmctx->p_tmsi_old = 0;
mmctx->pending_req = 0;
if (mmctx->ran_type == MM_CTX_T_GERAN_Gb) {
/* Unassign the old TLLI */
mmctx->gb.tlli = mmctx->gb.tlli_new;
//gprs_llgmm_assign(mmctx->gb.llme, 0xffffffff, mmctx->gb.tlli_new, GPRS_ALGO_GEA0, NULL);
}
rc = 0;
break;
case GSM48_MT_GMM_AUTH_CIPH_RESP:
if (!mmctx)
goto null_mmctx;
rc = gsm48_rx_gmm_auth_ciph_resp(mmctx, msg);
break;
case GSM48_MT_GMM_AUTH_CIPH_FAIL:
rc = gsm48_rx_gmm_auth_ciph_fail(mmctx, msg);
break;
default:
LOGMMCTXP(LOGL_NOTICE, mmctx, "Unknown GSM 04.08 GMM msg type 0x%02x\n",
gh->msg_type);
if (mmctx)
rc = gsm48_tx_gmm_status(mmctx, GMM_CAUSE_MSGT_NOTEXIST_NOTIMPL);
else
rc = -EINVAL;
break;
}
return rc;
null_mmctx:
LOGP(DMM, LOGL_ERROR,
"Received GSM 04.08 message type 0x%02x,"
" but no MM context available\n",
gh->msg_type);
return -EINVAL;
}
static void mmctx_timer_cb(void *_mm)
{
struct sgsn_mm_ctx *mm = _mm;
struct gsm_auth_tuple *at;
mm->num_T_exp++;
switch (mm->T) {
case 3350: /* waiting for ATTACH COMPLETE */
if (mm->num_T_exp >= 5) {
LOGMMCTXP(LOGL_NOTICE, mm, "T3350 expired >= 5 times\n");
mm_ctx_cleanup_free(mm, "T3350");
/* FIXME: should we return some error? */
break;
}
/* re-transmit the respective msg and re-start timer */
switch (mm->t3350_mode) {
case GMM_T3350_MODE_ATT:
gsm48_tx_gmm_att_ack(mm);
break;
case GMM_T3350_MODE_RAU:
gsm48_tx_gmm_ra_upd_ack(mm);
break;
case GMM_T3350_MODE_PTMSI_REALL:
/* FIXME */
break;
case GMM_T3350_MODE_NONE:
LOGMMCTXP(LOGL_NOTICE, mm,
"T3350 mode wasn't set, ignoring timeout\n");
break;
}
osmo_timer_schedule(&mm->timer, sgsn->cfg.timers.T3350, 0);
break;
case 3360: /* waiting for AUTH AND CIPH RESP */
if (mm->num_T_exp >= 5) {
LOGMMCTXP(LOGL_NOTICE, mm, "T3360 expired >= 5 times\n");
mm_ctx_cleanup_free(mm, "T3360");
break;
}
/* Re-transmit the respective msg and re-start timer */
if (mm->auth_triplet.key_seq == GSM_KEY_SEQ_INVAL) {
LOGMMCTXP(LOGL_ERROR, mm,
"timeout: invalid auth triplet reference\n");
mm_ctx_cleanup_free(mm, "T3360");
break;
}
at = &mm->auth_triplet;
gsm48_tx_gmm_auth_ciph_req(mm, &at->vec, at->key_seq, false);
osmo_timer_schedule(&mm->timer, sgsn->cfg.timers.T3360, 0);
break;
case 3370: /* waiting for IDENTITY RESPONSE */
if (mm->num_T_exp >= 5) {
LOGMMCTXP(LOGL_NOTICE, mm, "T3370 expired >= 5 times\n");
gsm48_tx_gmm_att_rej(mm, GMM_CAUSE_MS_ID_NOT_DERIVED);
mm_ctx_cleanup_free(mm, "GPRS ATTACH REJECT (T3370)");
break;
}
/* re-tranmit IDENTITY REQUEST and re-start timer */
gsm48_tx_gmm_id_req(mm, mm->t3370_id_type);
osmo_timer_schedule(&mm->timer, sgsn->cfg.timers.T3370, 0);
break;
default:
LOGMMCTXP(LOGL_ERROR, mm, "timer expired in unknown mode %u\n",
mm->T);
}
}
/* GPRS SESSION MANAGEMENT */
static void pdpctx_timer_cb(void *_mm);
static void pdpctx_timer_start(struct sgsn_pdp_ctx *pdp, unsigned int T,
unsigned int seconds)
{
if (osmo_timer_pending(&pdp->timer))
LOGPDPCTXP(LOGL_ERROR, pdp, "Starting PDP timer %u while old "
"timer %u pending\n", T, pdp->T);
pdp->T = T;
pdp->num_T_exp = 0;
/* FIXME: we should do this only once ? */
osmo_timer_setup(&pdp->timer, pdpctx_timer_cb, pdp);
osmo_timer_schedule(&pdp->timer, seconds, 0);
}
static void pdpctx_timer_stop(struct sgsn_pdp_ctx *pdp, unsigned int T)
{
if (pdp->T != T)
LOGPDPCTXP(LOGL_ERROR, pdp, "Stopping PDP timer %u but "
"%u is running\n", T, pdp->T);
osmo_timer_del(&pdp->timer);
}
#if 0
static void msgb_put_pdp_addr_ipv4(struct msgb *msg, uint32_t ipaddr)
{
uint8_t v[6];
v[0] = PDP_TYPE_ORG_IETF;
v[1] = PDP_TYPE_N_IETF_IPv4;
*(uint32_t *)(v+2) = htonl(ipaddr);
msgb_tlv_put(msg, GSM48_IE_GSM_PDP_ADDR, sizeof(v), v);
}
static void msgb_put_pdp_addr_ppp(struct msgb *msg)
{
uint8_t v[2];
v[0] = PDP_TYPE_ORG_ETSI;
v[1] = PDP_TYPE_N_ETSI_PPP;
msgb_tlv_put(msg, GSM48_IE_GSM_PDP_ADDR, sizeof(v), v);
}
#endif
/* Section 9.5.2: Activate PDP Context Accept */
int gsm48_tx_gsm_act_pdp_acc(struct sgsn_pdp_ctx *pdp)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 PDP ACC");
struct gsm48_hdr *gh;
uint8_t transaction_id = pdp->ti ^ 0x8; /* flip */
LOGPDPCTXP(LOGL_INFO, pdp, "<- ACTIVATE PDP CONTEXT ACK\n");
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_PDP_ACTIVATE_ACCEPT]);
mmctx2msgid(msg, pdp->mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_SM_GPRS | (transaction_id << 4);
gh->msg_type = GSM48_MT_GSM_ACT_PDP_ACK;
/* Negotiated LLC SAPI */
msgb_v_put(msg, pdp->sapi);
/* FIXME: copy QoS parameters from original request */
//msgb_lv_put(msg, pdp->lib->qos_neg.l, pdp->lib->qos_neg.v);
msgb_lv_put(msg, sizeof(default_qos), (uint8_t *)&default_qos);
/* Radio priority 10.5.7.2 */
msgb_v_put(msg, pdp->lib->radio_pri);
/* PDP address */
/* Highest 4 bits of first byte need to be set to 1, otherwise
* the IE is identical with the 04.08 PDP Address IE */
pdp->lib->eua.v[0] &= ~0xf0;
msgb_tlv_put(msg, GSM48_IE_GSM_PDP_ADDR,
pdp->lib->eua.l, pdp->lib->eua.v);
pdp->lib->eua.v[0] |= 0xf0;
/* Optional: Protocol configuration options (FIXME: why 'req') */
if (pdp->lib->pco_req.l)
msgb_tlv_put(msg, GSM48_IE_GSM_PROTO_CONF_OPT,
pdp->lib->pco_req.l, pdp->lib->pco_req.v);
/* Optional: Packet Flow Identifier */
return gsm48_gmm_sendmsg(msg, 0, pdp->mm, true);
}
/* Section 9.5.3: Activate PDP Context reject */
int gsm48_tx_gsm_act_pdp_rej(struct sgsn_mm_ctx *mm, uint8_t tid,
uint8_t cause, uint8_t pco_len, uint8_t *pco_v)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 PDP REJ");
struct gsm48_hdr *gh;
uint8_t transaction_id = tid ^ 0x8; /* flip */
LOGMMCTXP(LOGL_NOTICE, mm, "<- ACTIVATE PDP CONTEXT REJ(cause=%u)\n", cause);
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_PDP_ACTIVATE_REJECT]);
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_SM_GPRS | (transaction_id << 4);
gh->msg_type = GSM48_MT_GSM_ACT_PDP_REJ;
msgb_v_put(msg, cause);
if (pco_len && pco_v)
msgb_tlv_put(msg, GSM48_IE_GSM_PROTO_CONF_OPT, pco_len, pco_v);
return gsm48_gmm_sendmsg(msg, 0, mm, true);
}
/* Section 9.5.8: Deactivate PDP Context Request */
static int _gsm48_tx_gsm_deact_pdp_req(struct sgsn_mm_ctx *mm, uint8_t tid,
uint8_t sm_cause)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 PDP DET REQ");
struct gsm48_hdr *gh;
uint8_t transaction_id = tid ^ 0x8; /* flip */
LOGMMCTXP(LOGL_INFO, mm, "<- DEACTIVATE PDP CONTEXT REQ\n");
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_PDP_DL_DEACTIVATE_REQUEST]);
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_SM_GPRS | (transaction_id << 4);
gh->msg_type = GSM48_MT_GSM_DEACT_PDP_REQ;
msgb_v_put(msg, sm_cause);
return gsm48_gmm_sendmsg(msg, 0, mm, true);
}
int gsm48_tx_gsm_deact_pdp_req(struct sgsn_pdp_ctx *pdp, uint8_t sm_cause)
{
pdpctx_timer_start(pdp, 3395, sgsn->cfg.timers.T3395);
return _gsm48_tx_gsm_deact_pdp_req(pdp->mm, pdp->ti, sm_cause);
}
/* Section 9.5.9: Deactivate PDP Context Accept */
static int _gsm48_tx_gsm_deact_pdp_acc(struct sgsn_mm_ctx *mm, uint8_t tid)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 PDP DET ACC");
struct gsm48_hdr *gh;
uint8_t transaction_id = tid ^ 0x8; /* flip */
LOGMMCTXP(LOGL_INFO, mm, "<- DEACTIVATE PDP CONTEXT ACK\n");
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_PDP_DL_DEACTIVATE_ACCEPT]);
mmctx2msgid(msg, mm);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_SM_GPRS | (transaction_id << 4);
gh->msg_type = GSM48_MT_GSM_DEACT_PDP_ACK;
return gsm48_gmm_sendmsg(msg, 0, mm, true);
}
int gsm48_tx_gsm_deact_pdp_acc(struct sgsn_pdp_ctx *pdp)
{
return _gsm48_tx_gsm_deact_pdp_acc(pdp->mm, pdp->ti);
}
static int activate_ggsn(struct sgsn_mm_ctx *mmctx,
struct sgsn_ggsn_ctx *ggsn, const uint8_t transaction_id,
const uint8_t req_nsapi, const uint8_t req_llc_sapi,
struct tlv_parsed *tp, int destroy_ggsn)
{
struct sgsn_pdp_ctx *pdp;
LOGMMCTXP(LOGL_DEBUG, mmctx, "Using GGSN %u\n", ggsn->id);
ggsn->gsn = sgsn->gsn;
pdp = sgsn_create_pdp_ctx(ggsn, mmctx, req_nsapi, tp);
if (!pdp)
return -1;
/* Store SAPI and Transaction Identifier */
pdp->sapi = req_llc_sapi;
pdp->ti = transaction_id;
pdp->destroy_ggsn = destroy_ggsn;
return 0;
}
static void ggsn_lookup_cb(void *arg, int status, int timeouts, struct hostent *hostent)
{
struct sgsn_ggsn_ctx *ggsn;
struct sgsn_ggsn_lookup *lookup = arg;
struct in_addr *addr = NULL;
/* The context is gone while we made a request */
if (!lookup->mmctx) {
talloc_free(lookup->orig_msg);
talloc_free(lookup);
return;
}
if (status != ARES_SUCCESS) {
struct sgsn_mm_ctx *mmctx = lookup->mmctx;
LOGMMCTXP(LOGL_ERROR, mmctx, "DNS query failed.\n");
/* Need to try with three digits now */
if (lookup->state == SGSN_GGSN_2DIGIT) {
char *hostname;
int rc;
lookup->state = SGSN_GGSN_3DIGIT;
hostname = osmo_apn_qualify_from_imsi(mmctx->imsi,
lookup->apn_str, 1);
LOGMMCTXP(LOGL_DEBUG, mmctx,
"Going to query %s\n", hostname);
rc = sgsn_ares_query(sgsn, hostname,
ggsn_lookup_cb, lookup);
if (rc != 0) {
LOGMMCTXP(LOGL_ERROR, mmctx, "Couldn't start GGSN\n");
goto reject_due_failure;
}
return;
}
LOGMMCTXP(LOGL_ERROR, mmctx, "Couldn't resolve GGSN\n");
goto reject_due_failure;
}
if (hostent->h_length != sizeof(struct in_addr)) {
LOGMMCTXP(LOGL_ERROR, lookup->mmctx,
"Wrong addr size(%zu)\n", sizeof(struct in_addr));
goto reject_due_failure;
}
/* Get the first addr from the list */
addr = (struct in_addr *) hostent->h_addr_list[0];
if (!addr) {
LOGMMCTXP(LOGL_ERROR, lookup->mmctx, "No host address.\n");
goto reject_due_failure;
}
ggsn = sgsn_ggsn_ctx_alloc(UINT32_MAX);
if (!ggsn) {
LOGMMCTXP(LOGL_ERROR, lookup->mmctx, "Failed to create ggsn.\n");
goto reject_due_failure;
}
ggsn->remote_addr = *addr;
LOGMMCTXP(LOGL_NOTICE, lookup->mmctx,
"Selected %s as GGSN.\n", inet_ntoa(*addr));
/* forget about the ggsn look-up */
lookup->mmctx->ggsn_lookup = NULL;
activate_ggsn(lookup->mmctx, ggsn, lookup->ti, lookup->nsapi,
lookup->sapi, &lookup->tp, 1);
/* Now free it */
talloc_free(lookup->orig_msg);
talloc_free(lookup);
return;
reject_due_failure:
gsm48_tx_gsm_act_pdp_rej(lookup->mmctx, lookup->ti,
GMM_CAUSE_NET_FAIL, 0, NULL);
lookup->mmctx->ggsn_lookup = NULL;
talloc_free(lookup->orig_msg);
talloc_free(lookup);
}
static int do_act_pdp_req(struct sgsn_mm_ctx *mmctx, struct msgb *msg, bool *delete)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
struct gsm48_act_pdp_ctx_req *act_req = (struct gsm48_act_pdp_ctx_req *) gh->data;
uint8_t req_qos_len, req_pdpa_len;
uint8_t *req_qos, *req_pdpa;
struct tlv_parsed tp;
uint8_t transaction_id = gsm48_hdr_trans_id(gh);
struct sgsn_ggsn_ctx *ggsn;
struct sgsn_pdp_ctx *pdp;
enum gsm48_gsm_cause gsm_cause;
char apn_str[GSM_APN_LENGTH] = { 0, };
char *hostname;
int rc;
struct gprs_llc_lle *lle;
LOGMMCTXP(LOGL_INFO, mmctx, "-> ACTIVATE PDP CONTEXT REQ: SAPI=%u NSAPI=%u ",
act_req->req_llc_sapi, act_req->req_nsapi);
/* FIXME: length checks! */
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];
req_pdpa = act_req->data + 1 + req_qos_len + 1; /* 10.5.6.4 */
switch (req_pdpa[0] & 0xf) {
case 0x0:
DEBUGPC(DMM, "ETSI ");
break;
case 0x1:
DEBUGPC(DMM, "IETF ");
break;
case 0xf:
DEBUGPC(DMM, "Empty ");
break;
}
switch (req_pdpa[1]) {
case 0x21:
DEBUGPC(DMM, "IPv4 ");
if (req_pdpa_len >= 6) {
struct in_addr ia;
ia.s_addr = ntohl(*((uint32_t *) (req_pdpa+2)));
DEBUGPC(DMM, "%s ", inet_ntoa(ia));
}
break;
case 0x57:
DEBUGPC(DMM, "IPv6 ");
if (req_pdpa_len >= 18) {
/* FIXME: print IPv6 address */
}
break;
default:
DEBUGPC(DMM, "0x%02x ", req_pdpa[1]);
break;
}
LOGPC(DMM, LOGL_INFO, "\n");
/* Check if NSAPI is out of range (TS 04.65 / 7.2) */
if (act_req->req_nsapi < 5 || act_req->req_nsapi > 15) {
/* Send reject with GSM_CAUSE_INV_MAND_INFO */
return gsm48_tx_gsm_act_pdp_rej(mmctx, transaction_id,
GSM_CAUSE_INV_MAND_INFO,
0, NULL);
}
/* Optional: Access Point Name, Protocol Config Options */
if (req_pdpa + req_pdpa_len < msg->data + msg->len)
tlv_parse(&tp, &gsm48_sm_att_tlvdef, req_pdpa + req_pdpa_len,
(msg->data + msg->len) - (req_pdpa + req_pdpa_len), 0, 0);
else
memset(&tp, 0, sizeof(tp));
/* 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;
/* Check if NSAPI is already in use */
pdp = sgsn_pdp_ctx_by_nsapi(mmctx, act_req->req_nsapi);
if (pdp) {
/* We already have a PDP context for this TLLI + NSAPI tuple */
if (pdp->sapi == act_req->req_llc_sapi &&
pdp->ti == transaction_id) {
/* This apparently is a re-transmission of a PDP CTX
* ACT REQ (our ACT ACK must have got dropped) */
rc = gsm48_tx_gsm_act_pdp_acc(pdp);
if (rc < 0)
return rc;
if (pdp->mm->ran_type == MM_CTX_T_GERAN_Gb) {
/* Also re-transmit the SNDCP XID message */
lle = &pdp->mm->gb.llme->lle[pdp->sapi];
rc = sndcp_sn_xid_req(lle,pdp->nsapi);
if (rc < 0)
return rc;
}
return 0;
}
/* Send reject with GSM_CAUSE_NSAPI_IN_USE */
return gsm48_tx_gsm_act_pdp_rej(mmctx, transaction_id,
GSM_CAUSE_NSAPI_IN_USE,
0, NULL);
}
if (mmctx->ggsn_lookup) {
if (mmctx->ggsn_lookup->sapi == act_req->req_llc_sapi &&
mmctx->ggsn_lookup->ti == transaction_id) {
LOGMMCTXP(LOGL_NOTICE, mmctx,
"Re-transmission while doing look-up. Ignoring.\n");
return 0;
}
}
/* Only increment counter for a real activation, after we checked
* for re-transmissions */
rate_ctr_inc(&mmctx->ctrg->ctr[GMM_CTR_PDP_CTX_ACT]);
/* Determine GGSN based on APN and subscription options */
ggsn = sgsn_mm_ctx_find_ggsn_ctx(mmctx, &tp, &gsm_cause, apn_str);
if (ggsn)
return activate_ggsn(mmctx, ggsn, transaction_id,
act_req->req_nsapi, act_req->req_llc_sapi,
&tp, 0);
if (strlen(apn_str) == 0)
goto no_context;
if (!sgsn->cfg.dynamic_lookup)
goto no_context;
/* schedule a dynamic look-up */
mmctx->ggsn_lookup = talloc_zero(tall_bsc_ctx, struct sgsn_ggsn_lookup);
if (!mmctx->ggsn_lookup)
goto no_context;
mmctx->ggsn_lookup->state = SGSN_GGSN_2DIGIT;
mmctx->ggsn_lookup->mmctx = mmctx;
strcpy(mmctx->ggsn_lookup->apn_str, apn_str);
mmctx->ggsn_lookup->orig_msg = msg;
mmctx->ggsn_lookup->tp = tp;
mmctx->ggsn_lookup->ti = transaction_id;
mmctx->ggsn_lookup->nsapi = act_req->req_nsapi;
mmctx->ggsn_lookup->sapi = act_req->req_llc_sapi;
hostname = osmo_apn_qualify_from_imsi(mmctx->imsi,
mmctx->ggsn_lookup->apn_str, 0);
LOGMMCTXP(LOGL_DEBUG, mmctx, "Going to query %s\n", hostname);
rc = sgsn_ares_query(sgsn, hostname,
ggsn_lookup_cb, mmctx->ggsn_lookup);
if (rc != 0) {
LOGMMCTXP(LOGL_ERROR, mmctx, "Failed to start ares query.\n");
goto no_context;
}
*delete = 0;
return 0;
no_context:
LOGMMCTXP(LOGL_ERROR, mmctx, "No GGSN context found!\n");
return gsm48_tx_gsm_act_pdp_rej(mmctx, transaction_id,
gsm_cause, 0, NULL);
}
/* Section 9.5.1: Activate PDP Context Request */
static int gsm48_rx_gsm_act_pdp_req(struct sgsn_mm_ctx *mmctx,
struct msgb *_msg)
{
bool delete = 1;
struct msgb *msg;
int rc;
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_PDP_ACTIVATE_REQUEST]);
/*
* This is painful. We might not have a static GGSN
* configuration and then would need to copy the msg
* and re-do most of this routine (or call it again
* and make sure it only goes through the dynamic
* resolving. The question is what to optimize for
* and the dynamic resolution will be the right thing
* in the long run.
*/
msg = gprs_msgb_copy(_msg, __func__);
if (!msg) {
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(_msg);
uint8_t transaction_id = gsm48_hdr_trans_id(gh);
LOGMMCTXP(LOGL_ERROR, mmctx, "-> ACTIVATE PDP CONTEXT REQ failed copy.\n");
/* Send reject with GSM_CAUSE_INV_MAND_INFO */
return gsm48_tx_gsm_act_pdp_rej(mmctx, transaction_id,
GSM_CAUSE_NET_FAIL,
0, NULL);
}
rc = do_act_pdp_req(mmctx, msg, &delete);
if (delete)
msgb_free(msg);
return rc;
}
/* Section 9.5.8: Deactivate PDP Context Request */
static int gsm48_rx_gsm_deact_pdp_req(struct sgsn_mm_ctx *mm, struct msgb *msg)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t transaction_id = gsm48_hdr_trans_id(gh);
struct sgsn_pdp_ctx *pdp;
LOGMMCTXP(LOGL_INFO, mm, "-> DEACTIVATE PDP CONTEXT REQ (cause: %s)\n",
get_value_string(gsm48_gsm_cause_names, gh->data[0]));
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_PDP_UL_DEACTIVATE_REQUEST]);
pdp = sgsn_pdp_ctx_by_tid(mm, transaction_id);
if (!pdp) {
LOGMMCTXP(LOGL_NOTICE, mm, "Deactivate PDP Context Request for "
"non-existing PDP Context (IMSI=%s, TI=%u)\n",
mm->imsi, transaction_id);
return _gsm48_tx_gsm_deact_pdp_acc(mm, transaction_id);
}
return sgsn_delete_pdp_ctx(pdp);
}
/* Section 9.5.9: Deactivate PDP Context Accept */
static int gsm48_rx_gsm_deact_pdp_ack(struct sgsn_mm_ctx *mm, struct msgb *msg)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t transaction_id = gsm48_hdr_trans_id(gh);
struct sgsn_pdp_ctx *pdp;
LOGMMCTXP(LOGL_INFO, mm, "-> DEACTIVATE PDP CONTEXT ACK\n");
rate_ctr_inc(&sgsn->rate_ctrs->ctr[CTR_PDP_UL_DEACTIVATE_ACCEPT]);
pdp = sgsn_pdp_ctx_by_tid(mm, transaction_id);
if (!pdp) {
LOGMMCTXP(LOGL_NOTICE, mm, "Deactivate PDP Context Accept for "
"non-existing PDP Context (IMSI=%s, TI=%u)\n",
mm->imsi, transaction_id);
return 0;
}
/* stop timer 3395 */
pdpctx_timer_stop(pdp, 3395);
return sgsn_delete_pdp_ctx(pdp);
}
static int gsm48_rx_gsm_status(struct sgsn_mm_ctx *ctx, struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
LOGMMCTXP(LOGL_INFO, ctx, "-> GPRS SM STATUS (cause: %s)\n",
get_value_string(gsm48_gsm_cause_names, gh->data[0]));
return 0;
}
static void pdpctx_timer_cb(void *_pdp)
{
struct sgsn_pdp_ctx *pdp = _pdp;
pdp->num_T_exp++;
switch (pdp->T) {
case 3395: /* waiting for PDP CTX DEACT ACK */
if (pdp->num_T_exp >= 4) {
LOGPDPCTXP(LOGL_NOTICE, pdp, "T3395 expired >= 5 times\n");
pdp->state = PDP_STATE_INACTIVE;
sgsn_delete_pdp_ctx(pdp);
break;
}
gsm48_tx_gsm_deact_pdp_req(pdp, GSM_CAUSE_NET_FAIL);
break;
default:
LOGPDPCTXP(LOGL_ERROR, pdp, "timer expired in unknown mode %u\n",
pdp->T);
}
}
/* GPRS Session Management */
static int gsm0408_rcv_gsm(struct sgsn_mm_ctx *mmctx, struct msgb *msg,
struct gprs_llc_llme *llme)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
int rc;
/* MMCTX can be NULL when called */
if (!mmctx) {
LOGP(DMM, LOGL_NOTICE, "Cannot handle SM for unknown MM CTX\n");
/* 6.1.3.6 */
if (gh->msg_type == GSM48_MT_GSM_STATUS)
return 0;
return gsm0408_gprs_force_reattach_oldmsg(msg, llme);
}
switch (gh->msg_type) {
case GSM48_MT_GSM_ACT_PDP_REQ:
rc = gsm48_rx_gsm_act_pdp_req(mmctx, msg);
break;
case GSM48_MT_GSM_DEACT_PDP_REQ:
rc = gsm48_rx_gsm_deact_pdp_req(mmctx, msg);
break;
case GSM48_MT_GSM_DEACT_PDP_ACK:
rc = gsm48_rx_gsm_deact_pdp_ack(mmctx, msg);
break;
case GSM48_MT_GSM_STATUS:
rc = gsm48_rx_gsm_status(mmctx, msg);
break;
case GSM48_MT_GSM_REQ_PDP_ACT_REJ:
case GSM48_MT_GSM_ACT_AA_PDP_REQ:
case GSM48_MT_GSM_DEACT_AA_PDP_REQ:
LOGMMCTXP(LOGL_NOTICE, mmctx, "Unimplemented GSM 04.08 GSM msg type 0x%02x: %s\n",
gh->msg_type, osmo_hexdump((uint8_t *)gh, msgb_l3len(msg)));
rc = gsm48_tx_sm_status(mmctx, GSM_CAUSE_MSGT_NOTEXIST_NOTIMPL);
break;
default:
LOGMMCTXP(LOGL_NOTICE, mmctx, "Unknown GSM 04.08 GSM msg type 0x%02x: %s\n",
gh->msg_type, osmo_hexdump((uint8_t *)gh, msgb_l3len(msg)));
rc = gsm48_tx_sm_status(mmctx, GSM_CAUSE_MSGT_NOTEXIST_NOTIMPL);
break;
}
return rc;
}
int gsm0408_gprs_force_reattach_oldmsg(struct msgb *msg,
struct gprs_llc_llme *llme)
{
int rc;
if (llme)
gprs_llgmm_reset_oldmsg(msg, GPRS_SAPI_GMM, llme);
rc = gsm48_tx_gmm_detach_req_oldmsg(
msg, GPRS_DET_T_MT_REATT_REQ, GMM_CAUSE_IMPL_DETACHED);
return rc;
}
int gsm0408_gprs_force_reattach(struct sgsn_mm_ctx *mmctx)
{
int rc;
if (mmctx->ran_type == MM_CTX_T_GERAN_Gb)
gprs_llgmm_reset(mmctx->gb.llme);
rc = gsm48_tx_gmm_detach_req(
mmctx, GPRS_DET_T_MT_REATT_REQ, GMM_CAUSE_IMPL_DETACHED);
mm_ctx_cleanup_free(mmctx, "forced reattach");
return rc;
}
/* Main entry point for incoming 04.08 GPRS messages from Iu */
int gsm0408_gprs_rcvmsg_iu(struct msgb *msg, struct gprs_ra_id *ra_id,
uint16_t *sai)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t pdisc = gsm48_hdr_pdisc(gh);
struct sgsn_mm_ctx *mmctx;
int rc = -EINVAL;
mmctx = sgsn_mm_ctx_by_ue_ctx(msg->dst);
if (mmctx) {
rate_ctr_inc(&mmctx->ctrg->ctr[GMM_CTR_PKTS_SIG_IN]);
if (ra_id)
memcpy(&mmctx->ra, ra_id, sizeof(mmctx->ra));
}
/* MMCTX can be NULL */
switch (pdisc) {
case GSM48_PDISC_MM_GPRS:
rc = gsm0408_rcv_gmm(mmctx, msg, NULL, false);
#warning "set drop_cipherable arg for gsm0408_rcv_gmm() from IuPS?"
break;
case GSM48_PDISC_SM_GPRS:
rc = gsm0408_rcv_gsm(mmctx, msg, NULL);
break;
default:
LOGMMCTXP(LOGL_NOTICE, mmctx,
"Unknown GSM 04.08 discriminator 0x%02x: %s\n",
pdisc, osmo_hexdump((uint8_t *)gh, msgb_l3len(msg)));
/* FIXME: return status message */
break;
}
/* MMCTX can be invalid */
return rc;
}
/* Main entry point for incoming 04.08 GPRS messages from Gb */
int gsm0408_gprs_rcvmsg_gb(struct msgb *msg, struct gprs_llc_llme *llme,
bool drop_cipherable)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
uint8_t pdisc = gsm48_hdr_pdisc(gh);
struct sgsn_mm_ctx *mmctx;
struct gprs_ra_id ra_id;
int rc = -EINVAL;
bssgp_parse_cell_id(&ra_id, msgb_bcid(msg));
mmctx = sgsn_mm_ctx_by_tlli(msgb_tlli(msg), &ra_id);
if (mmctx) {
msgid2mmctx(mmctx, msg);
rate_ctr_inc(&mmctx->ctrg->ctr[GMM_CTR_PKTS_SIG_IN]);
mmctx->gb.llme = llme;
}
/* MMCTX can be NULL */
switch (pdisc) {
case GSM48_PDISC_MM_GPRS:
rc = gsm0408_rcv_gmm(mmctx, msg, llme, drop_cipherable);
break;
case GSM48_PDISC_SM_GPRS:
rc = gsm0408_rcv_gsm(mmctx, msg, llme);
break;
default:
LOGMMCTXP(LOGL_NOTICE, mmctx,
"Unknown GSM 04.08 discriminator 0x%02x: %s\n",
pdisc, osmo_hexdump((uint8_t *)gh, msgb_l3len(msg)));
/* FIXME: return status message */
break;
}
/* MMCTX can be invalid */
return rc;
}
int gprs_gmm_rx_suspend(struct gprs_ra_id *raid, uint32_t tlli)
{
struct sgsn_mm_ctx *mmctx;
mmctx = sgsn_mm_ctx_by_tlli(tlli, raid);
if (!mmctx) {
LOGP(DMM, LOGL_NOTICE, "SUSPEND request for unknown "
"TLLI=%08x\n", tlli);
return -EINVAL;
}
if (mmctx->gmm_state != GMM_REGISTERED_NORMAL &&
mmctx->gmm_state != GMM_REGISTERED_SUSPENDED) {
LOGMMCTXP(LOGL_NOTICE, mmctx, "SUSPEND request while state "
"!= REGISTERED (TLLI=%08x)\n", tlli);
return -EINVAL;
}
/* Transition from REGISTERED_NORMAL to REGISTERED_SUSPENDED */
mmctx->gmm_state = GMM_REGISTERED_SUSPENDED;
return 0;
}
int gprs_gmm_rx_resume(struct gprs_ra_id *raid, uint32_t tlli,
uint8_t suspend_ref)
{
struct sgsn_mm_ctx *mmctx;
/* FIXME: make use of suspend reference? */
mmctx = sgsn_mm_ctx_by_tlli(tlli, raid);
if (!mmctx) {
LOGP(DMM, LOGL_NOTICE, "RESUME request for unknown "
"TLLI=%08x\n", tlli);
return -EINVAL;
}
if (mmctx->gmm_state != GMM_REGISTERED_NORMAL &&
mmctx->gmm_state != GMM_REGISTERED_SUSPENDED) {
LOGMMCTXP(LOGL_NOTICE, mmctx, "RESUME request while state "
"!= SUSPENDED (TLLI=%08x)\n", tlli);
/* FIXME: should we not simply ignore it? */
return -EINVAL;
}
/* Transition from SUSPENDED to NORMAL */
mmctx->gmm_state = GMM_REGISTERED_NORMAL;
return 0;
}
#ifdef BUILD_IU
int iu_rab_act_ps(uint8_t rab_id, struct sgsn_pdp_ctx *pdp, bool use_x213_nsap)
{
struct msgb *msg;
struct sgsn_mm_ctx *mm = pdp->mm;
struct ue_conn_ctx *uectx;
uint32_t ggsn_ip;
uectx = mm->iu.ue_ctx;
/* Get the IP address for ggsn user plane */
memcpy(&ggsn_ip, pdp->lib->gsnru.v, pdp->lib->gsnru.l);
ggsn_ip = htonl(ggsn_ip);
LOGP(DRANAP, LOGL_DEBUG, "Assigning RAB: rab_id=%d, ggsn_ip=%x,"
" teid_gn=%x, use_x213_nsap=%d\n",
rab_id, ggsn_ip, pdp->lib->teid_gn, use_x213_nsap);
msg = ranap_new_msg_rab_assign_data(rab_id, ggsn_ip,
pdp->lib->teid_gn, use_x213_nsap);
msg->l2h = msg->data;
return iu_rab_act(uectx, msg);
}
#endif
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