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osmo-sgsn/src/sgsn/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 "config.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/core/tdef.h>
#include <osmocom/crypt/auth.h>
#include <osmocom/crypt/utran_cipher.h>
#include <osmocom/gsm/protocol/gsm_04_08_gprs.h>
#include <osmocom/gprs/gprs_bssgp.h>
#include <osmocom/sgsn/debug.h>
#include <osmocom/sgsn/gprs_llc.h>
#include <osmocom/sgsn/gprs_sgsn.h>
#include <osmocom/sgsn/gprs_gmm.h>
#include <osmocom/sgsn/gprs_utils.h>
#include <osmocom/sgsn/gprs_subscriber.h>
#include <osmocom/sgsn/sgsn.h>
#include <osmocom/sgsn/gprs_gmm_attach.h>
#include <osmocom/sgsn/gprs_mm_state_gb_fsm.h>
#include <osmocom/sgsn/gprs_mm_state_iu_fsm.h>
#include <osmocom/sgsn/gprs_gmm_fsm.h>
#include <osmocom/sgsn/signal.h>
#include <osmocom/sgsn/gprs_sndcp.h>
#include <osmocom/sgsn/gprs_ranap.h>
#include <osmocom/sgsn/gprs_sm.h>
#include <osmocom/sgsn/gtp.h>
#include <osmocom/sgsn/pdpctx.h>
#include <pdp.h>
#define PTMSI_ALLOC
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 },
},
};
/* 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 long seconds;
if (osmo_timer_pending(&mm->timer))
LOGMMCTXP(LOGL_ERROR, mm, "Starting MM timer %u while old "
"timer %u pending\n", T, mm->T);
seconds = osmo_tdef_get(sgsn->cfg.T_defs, T, OSMO_TDEF_S, -1);
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)
{
unsigned long T3314, T3312;
T3314 = osmo_tdef_get(sgsn->cfg.T_defs, 3314, OSMO_TDEF_S, -1);
T3312 = osmo_tdef_get(sgsn->cfg.T_defs, 3312, OSMO_TDEF_S, -1);
return T3314 + (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. */
int gsm48_gmm_sendmsg(struct msgb *msg, int command,
struct sgsn_mm_ctx *mm, bool encryptable)
{
if (mm) {
rate_ctr_inc(rate_ctr_group_get_ctr(mm->ctrg, GMM_CTR_PKTS_SIG_OUT));
#ifdef BUILD_IU
if (mm->ran_type == MM_CTX_T_UTRAN_Iu)
return ranap_iu_tx(msg, GPRS_SAPI_GMM);
#endif
}
#ifdef BUILD_IU
if (MSG_IU_UE_CTX(msg))
return ranap_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_IU_UE_CTX_SET(msg, MSG_IU_UE_CTX(old));
}
/* Store BVCI/NSEI in MM context */
void msgid2mmctx(struct sgsn_mm_ctx *mm, const struct msgb *msg)
{
/* check for Iu or Gb */
if (!MSG_IU_UE_CTX(msg)) {
mm->gb.bvci = msgb_bvci(msg);
mm->gb.nsei = msgb_nsei(msg);
}
#ifdef BUILD_IU
else {
/* In case a Iu connection is reconnected we need to update the ue ctx */
/* FIXME: the old ue_ctx have to be freed/disconnected */
mm->iu.ue_ctx = MSG_IU_UE_CTX(msg);
if (mm->ran_type == MM_CTX_T_UTRAN_Iu
&& mm->iu.ue_ctx) {
mm->iu.ue_ctx->rab_assign_addr_enc =
sgsn->cfg.iu.rab_assign_addr_enc;
}
}
#endif
}
/* Store BVCI/NSEI in MM context */
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_IU_UE_CTX_SET(msg, 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 */
osmo_fsm_inst_dispatch(ctx->gmm_fsm, E_GMM_CLEANUP, NULL);
switch(ctx->ran_type) {
case MM_CTX_T_UTRAN_Iu:
osmo_fsm_inst_dispatch(ctx->iu.mm_state_fsm, E_PMM_PS_DETACH, NULL);
break;
case MM_CTX_T_GERAN_Gb:
osmo_fsm_inst_dispatch(ctx->gb.mm_state_fsm, E_MM_GPRS_DETACH, NULL);
break;
}
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)
{
struct gsm48_hdr *gh;
/* MMCTX might be NULL! */
DEBUGP(DMM, "<- GMM STATUS (cause: %s)\n",
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_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);
}
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, "<- GMM 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);
}
/* Chapter 9.4.2: Attach accept */
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;
unsigned long t;
#ifdef PTMSI_ALLOC
struct osmo_mobile_identity mi;
uint8_t *l;
int rc;
#endif
#if 0
uint8_t *ptsig;
#endif
LOGMMCTXP(LOGL_INFO, mm, "<- GMM ATTACH ACCEPT (new P-TMSI=0x%08x)\n", mm->p_tmsi);
rate_ctr_inc(rate_ctr_group_get_ctr(sgsn->rate_ctrs, 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 */
t = osmo_tdef_get(sgsn->cfg.T_defs, 3312, OSMO_TDEF_S, -1);
aa->ra_upd_timer = gprs_secs_to_tmr_floor(t);
aa->radio_prio = 0x44; /* lowest */
gsm48_encode_ra(&aa->ra_id, &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.
*/
t = osmo_tdef_get(sgsn->cfg.T_defs, 3314, OSMO_TDEF_S, -1);
msgb_tv_put(msg, GSM48_IE_GMM_TIMER_READY, gprs_secs_to_tmr_floor(t));
#ifdef PTMSI_ALLOC
/* Optional: Allocated P-TMSI */
mi = (struct osmo_mobile_identity){
.type = GSM_MI_TYPE_TMSI,
.tmsi = mm->p_tmsi,
};
l = msgb_tl_put(msg, GSM48_IE_GMM_ALLOC_PTMSI);
rc = osmo_mobile_identity_encode_msgb(msg, &mi, false);
if (rc < 0) {
LOGMMCTXP(LOGL_ERROR, mm, "Cannot encode Mobile Identity\n");
msgb_free(msg);
return -EINVAL;
}
*l = rc;
#endif
/* Optional: MS-identity (combined attach) */
/* Optional: GMM cause (partial attach result for combined attach) */
/* Optional: Network feature support 10.5.5.23 */
/* msgb_v_put(msg, GSM48_IE_GMM_NET_FEAT_SUPPORT | 0x00);*/
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, "<- GMM ATTACH REJECT: %s\n",
get_value_string(gsm48_gmm_cause_names, gmm_cause));
rate_ctr_inc(rate_ctr_group_get_ctr(sgsn->rate_ctrs, 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);
}
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, "<- GMM DETACH ACC (force-standby: %d)\n", force_stby);
rate_ctr_inc(rate_ctr_group_get_ctr(sgsn->rate_ctrs, 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 */
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, "<- GMM 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;
}
static enum gprs_ciph_algo gprs_ms_net_select_best_gea(uint8_t net_mask, uint8_t ms_mask) {
uint8_t common_mask = net_mask & ms_mask;
uint8_t r = 0;
while (common_mask >>= 1) {
r++;
}
return r;
}
/* 3GPP TS 24.008 § 9.4.9: Authentication and Ciphering Request */
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;
int rc;
LOGMMCTXP(LOGL_INFO, mm, "<- GMM AUTH AND CIPHERING REQ (rand = %s,"
" mmctx_is_r99=%d, vec->auth_types=0x%x",
osmo_hexdump(vec->rand, sizeof(vec->rand)),
mmctx_is_r99(mm), vec->auth_types);
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: */
rc = osmo_get_rand_id(&rbyte, 1);
if (rc < 0) {
LOGMMCTXP(LOGL_ERROR, mm, "osmo_get_rand_id() failed for A&C ref: %s\n", strerror(-rc));
return rc;
}
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);
}
/* 3GPP TS 24.008 § 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, "<- GMM 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 enum osmo_sub_auth_type 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;
/* 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.
* However, on GERAN, even if we sent a UMTS AKA Authentication Request, the MS may decide to
* instead reply with a GSM AKA SRES response. */
if (is_utran
|| (mmctx_is_r99(ctx) && (vec->auth_types & OSMO_AUTH_TYPE_UMTS)
&& (res_len > sizeof(vec->sres)))) {
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 OSMO_AUTH_TYPE_NONE;
}
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 expect_type;
auth_mismatch:
LOGMMCTXP(LOGL_ERROR, ctx, "Auth mismatch: expected %s = %s\n",
expect_str, osmo_hexdump_nospc(expect_res, expect_res_len));
return OSMO_AUTH_TYPE_NONE;
}
/* 3GPP TS 24.008 § 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, "-> GMM 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));
ctx->sec_ctx = check_auth_resp(ctx, false, &at->vec, res, res_len);
if (!sgsn_mm_ctx_is_authenticated(ctx)) {
rc = gsm48_tx_gmm_auth_ciph_rej(ctx);
mm_ctx_cleanup_free(ctx, "GMM AUTH AND CIPH REJECT");
return rc;
}
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 osmo_fsm_inst_dispatch(ctx->gmm_att_req.fsm, E_AUTH_RESP_RECV_SUCCESS, NULL);
}
/* 3GPP TS 24.008 § 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, "-> GMM 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 osmo_fsm_inst_dispatch(ctx->gmm_att_req.fsm, E_AUTH_RESP_RECV_RESYNC, NULL);
/* 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, "GMM AUTH FAILURE");
return rc;
}
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));
}
}
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, "<- GMM 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, "<- GMM 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);
/* Check if we can already authorize a subscriber */
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);
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);
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
&& !sgsn_mm_ctx_is_authenticated(ctx)) {
struct gsm_auth_tuple *at = &ctx->auth_triplet;
mmctx_timer_start(ctx, 3360);
return gsm48_tx_gmm_auth_ciph_req(ctx, &at->vec, at->key_seq,
false);
}
if (ctx->auth_state == SGSN_AUTH_AUTHENTICATE && sgsn_mm_ctx_is_authenticated(ctx) &&
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) {
/* Is any encryption above UEA0 enabled? */
bool send_ck = sgsn->cfg.uea_encryption_mask > (1 << OSMO_UTRAN_UEA0);
LOGMMCTXP(LOGL_DEBUG, ctx, "Iu Security Mode Command: %s encryption key (UEA encryption mask = 0x%x)\n",
send_ck ? "sending" : "not sending", sgsn->cfg.uea_encryption_mask);
/* FIXME: we should send the set of allowed UEA, as in ranap_new_msg_sec_mod_cmd2(). However, this
* is not possible in the iu_client API. See OS#5487. */
rc = ranap_iu_tx_sec_mode_cmd(ctx->iu.ue_ctx, &ctx->auth_triplet.vec, send_ck, 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);
ctx->t3350_mode = GMM_T3350_MODE_ATT;
#else
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = ctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_ATTACH, &sig_data);
osmo_fsm_inst_dispatch(ctx->gmm_fsm, E_GMM_ATTACH_SUCCESS, NULL);
#endif
return gsm48_tx_gmm_att_ack(ctx);
#ifdef BUILD_IU
case GSM48_MT_GMM_SERVICE_REQ:
ctx->pending_req = 0;
osmo_fsm_inst_dispatch(ctx->iu.mm_state_fsm, E_PMM_PS_CONN_ESTABLISH, NULL);
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->sec_ctx = OSMO_AUTH_TYPE_NONE;
if (ctx->gmm_att_req.fsm->state != ST_INIT)
osmo_fsm_inst_dispatch(ctx->gmm_att_req.fsm, E_VLR_ANSWERED, (void *) 0);
else
gsm48_gmm_authorize(ctx);
}
void gsm0408_gprs_access_granted(struct sgsn_mm_ctx *ctx)
{
switch (ctx->gmm_fsm->state) {
case ST_GMM_COMMON_PROC_INIT:
LOGMMCTXP(LOGL_NOTICE, ctx,
"Authorized, continuing procedure, IMSI=%s\n",
ctx->imsi);
/* Continue with the authorization */
if (ctx->gmm_att_req.fsm->state != ST_INIT)
osmo_fsm_inst_dispatch(ctx->gmm_att_req.fsm, E_VLR_ANSWERED, (void *) 0);
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_fsm->state) {
case ST_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);
if (ctx->gmm_att_req.fsm->state != ST_INIT)
osmo_fsm_inst_dispatch(ctx->gmm_att_req.fsm, E_REJECT, (void *) (long) gmm_cause);
break;
case ST_GMM_REGISTERED_NORMAL:
case ST_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_IMSI, 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);
long mi_typel;
char mi_log_string[32];
struct osmo_mobile_identity mi;
if (!ctx) {
DEBUGP(DMM, "from unknown TLLI 0x%08x?!? This should not happen\n", msgb_tlli(msg));
return -EINVAL;
}
if (osmo_mobile_identity_decode(&mi, &gh->data[1], gh->data[0], false)) {
LOGMMCTXP(LOGL_ERROR, ctx, "-> GMM IDENTITY RESPONSE: cannot decode Mobile Identity\n");
return -EINVAL;
}
osmo_mobile_identity_to_str_buf(mi_log_string, sizeof(mi_log_string), &mi);
LOGMMCTXP(LOGL_DEBUG, ctx, "-> GMM IDENTITY RESPONSE: MI=%s\n", mi_log_string);
if (ctx->t3370_id_type == GSM_MI_TYPE_NONE) {
LOGMMCTXP(LOGL_NOTICE, ctx,
"Got unexpected IDENTITY RESPONSE: MI=%s, "
"ignoring message\n",
mi_log_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.imsi);
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, "GMM IMSI re-use");
}
}
OSMO_STRLCPY_ARRAY(ctx->imsi, mi.imsi);
break;
case GSM_MI_TYPE_IMEI:
OSMO_STRLCPY_ARRAY(ctx->imei, mi.imei);
break;
case GSM_MI_TYPE_IMEISV:
break;
}
/* Check if we can let the mobile station enter */
mi_typel = mi.type;
return osmo_fsm_inst_dispatch(ctx->gmm_att_req.fsm, E_IDEN_RESP_RECV, (void *)mi_typel);
}
/* Allocate a new P-TMSI and change context state */
static inline void ptmsi_update(struct sgsn_mm_ctx *ctx)
{
uint32_t ptmsi;
/* Don't change the P-TMSI if a P-TMSI re-assignment is under way */
if (ctx->gmm_fsm->state != ST_GMM_COMMON_PROC_INIT) {
ptmsi = sgsn_alloc_ptmsi();
if (ptmsi != GSM_RESERVED_TMSI) {
ctx->p_tmsi_old = ctx->p_tmsi;
ctx->p_tmsi = ptmsi;
} else
LOGMMCTXP(LOGL_ERROR, ctx, "P-TMSI allocation failure: using old one.\n");
}
osmo_fsm_inst_dispatch(ctx->gmm_fsm, E_GMM_COMMON_PROC_INIT_REQ, NULL);
}
/* Detect if RAT has changed */
static bool mmctx_did_rat_change(struct sgsn_mm_ctx *mmctx, struct msgb *msg)
{
if (MSG_IU_UE_CTX(msg) && mmctx->ran_type != MM_CTX_T_UTRAN_Iu)
return true;
if (!MSG_IU_UE_CTX(msg) && mmctx->ran_type != MM_CTX_T_GERAN_Gb)
return true;
return false;
}
/* Notify the FSM of a RAT change */
static void mmctx_handle_rat_change(struct sgsn_mm_ctx *mmctx, struct msgb *msg, struct gprs_llc_llme *llme)
{
struct gmm_rat_change_data rat_chg = {
.llme = llme
};
rat_chg.new_ran_type = MSG_IU_UE_CTX(msg) ? MM_CTX_T_UTRAN_Iu : MM_CTX_T_GERAN_Gb;
if (rat_chg.new_ran_type != mmctx->ran_type)
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_RAT_CHANGE, (void *) &rat_chg);
else
LOGMMCTXP(LOGL_ERROR, mmctx, "RAT didn't change or not implemented (ran_type=%u, "
"msg_iu_ue_ctx=%p\n", mmctx->ran_type, MSG_IU_UE_CTX(msg));
}
static uint8_t gprs_ms_net_cap_gea_mask(const uint8_t *ms_net_cap, uint8_t cap_len)
{
uint8_t mask = (1 << GPRS_ALGO_GEA0);
mask |= (0x80 & ms_net_cap[0]) ? (1 << GPRS_ALGO_GEA1) : 0;
if (cap_len < 2)
return mask;
/* extended GEA bits start from 2nd bit of the next byte */
mask |= (0x40 & ms_net_cap[1]) ? (1 << GPRS_ALGO_GEA2) : 0;
mask |= (0x20 & ms_net_cap[1]) ? (1 << GPRS_ALGO_GEA3) : 0;
mask |= (0x10 & ms_net_cap[1]) ? (1 << GPRS_ALGO_GEA4) : 0;
return mask;
}
/* 3GPP TS 24.008 § 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_data, *ms_ra_acc_cap;
uint8_t msnc_len, att_type, mi_len, ms_ra_acc_cap_len;
uint16_t drx_par;
char mi_log_string[32];
struct gprs_ra_id ra_id;
uint16_t cid = 0;
enum gsm48_gmm_cause reject_cause;
struct osmo_mobile_identity mi;
int rc;
LOGMMCTXP(LOGL_INFO, ctx, "-> GMM ATTACH REQUEST ");
rate_ctr_inc(rate_ctr_group_get_ctr(sgsn->rate_ctrs, 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. */
if (!MSG_IU_UE_CTX(msg)) {
/* Gb mode */
cid = bssgp_parse_cell_id(&ra_id, msgb_bcid(msg));
} else {
#ifdef BUILD_IU
ra_id = MSG_IU_UE_CTX(msg)->ra_id;
#else
LOGMMCTXP(LOGL_ERROR, ctx, "Cannot handle Iu Attach Request, built without Iu support\n");
return -ENOTSUP;
#endif
}
/* 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.
* The follow-on request can be signaled in an Attach Request on IuPS.
* This means the MS/UE asks to keep the PS connection open for further requests
* after the Attach Request succeed.
* The SGSN can decide if it close the connection or not. Both are spec conform. */
/* 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_data = cur;
cur += mi_len;
rc = osmo_mobile_identity_decode(&mi, mi_data, mi_len, false);
if (rc)
goto err_inval;
osmo_mobile_identity_to_str_buf(mi_log_string, sizeof(mi_log_string), &mi);
DEBUGPC(DMM, "MI(%s) type=\"%s\" ", mi_log_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.imsi);
if (!ctx) {
if (MSG_IU_UE_CTX(msg))
ctx = sgsn_mm_ctx_alloc_iu(MSG_IU_UE_CTX(msg));
else
ctx = sgsn_mm_ctx_alloc_gb(0, &ra_id);
if (!ctx) {
reject_cause = GMM_CAUSE_NET_FAIL;
goto rejected;
}
OSMO_STRLCPY_ARRAY(ctx->imsi, mi.imsi);
}
break;
case GSM_MI_TYPE_TMSI:
/* Try to find MM context based on P-TMSI */
if (!ctx)
ctx = sgsn_mm_ctx_by_ptmsi(mi.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_IU_UE_CTX(msg))
ctx = sgsn_mm_ctx_alloc_iu(MSG_IU_UE_CTX(msg));
else
ctx = sgsn_mm_ctx_alloc_gb(msgb_tlli(msg), &ra_id);
if (!ctx) {
reject_cause = GMM_CAUSE_NET_FAIL;
goto rejected;
}
ctx->p_tmsi = mi.tmsi;
}
break;
default:
LOGMMCTXP(LOGL_NOTICE, ctx, "Rejecting ATTACH REQUEST with "
"MI %s\n", mi_log_string);
reject_cause = GMM_CAUSE_MS_ID_NOT_DERIVED;
goto rejected;
}
if (mmctx_did_rat_change(ctx, msg))
mmctx_handle_rat_change(ctx, msg, llme);
if (ctx->ran_type == MM_CTX_T_GERAN_Gb) {
ctx->gb.tlli = msgb_tlli(msg);
ctx->gb.llme = llme;
}
msgid2mmctx(ctx, msg);
/* 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;
/* 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);
ctx->ue_cipher_mask = gprs_ms_net_cap_gea_mask(ctx->ms_network_capa.buf, msnc_len);
if (!(ctx->ue_cipher_mask & sgsn->cfg.gea_encryption_mask)) {
reject_cause = GMM_CAUSE_PROTO_ERR_UNSPEC;
LOGMMCTXP(LOGL_NOTICE, ctx, "Rejecting ATTACH REQUEST with MI "
"%s because MS do not support required encryption, mask UE:0x%02x NW:0x%02x \n",
mi_log_string, ctx->ue_cipher_mask, sgsn->cfg.gea_encryption_mask);
goto rejected;
}
/* just assume that everythig is fine if the phone offers a5/4:
* it requires a valid umts security context which we can only have after
* 1) IDENTITY REQUEST to know what to ask the HLR for
* 2) and AUTHENTICATION AND CIPHERING REQUEST
* ... but 2) already requires selecting a cipher mode.
* So let's just assume we will have the auth data required to make it work.
*/
ctx->ciph_algo = gprs_ms_net_select_best_gea(ctx->ue_cipher_mask, sgsn->cfg.gea_encryption_mask);
#ifdef PTMSI_ALLOC
/* Allocate a new P-TMSI (+ P-TMSI signature) and update TLLI */
ptmsi_update(ctx);
#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 (sgsn_mm_ctx_is_authenticated(ctx))
gprs_llme_copy_key(ctx, ctx->gb.llme);
gprs_llgmm_assign(ctx->gb.llme, ctx->gb.tlli, ctx->gb.tlli_new);
}
osmo_fsm_inst_dispatch(ctx->gmm_att_req.fsm, E_ATTACH_REQ_RECV, msg);
return 0;
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, "GMM ATTACH REJ");
else if (llme)
gprs_llgmm_unassign(llme);
return rc;
}
/* 3GPP TS 24.008 § 9.4.3 Attach complete */
static int gsm48_rx_gmm_att_compl(struct sgsn_mm_ctx *mmctx)
{
struct sgsn_signal_data sig_data;
/* only in case SGSN offered new P-TMSI */
LOGMMCTXP(LOGL_INFO, mmctx, "-> GMM ATTACH COMPLETE\n");
#ifdef BUILD_IU
if (mmctx->iu.ue_ctx) {
ranap_iu_tx_release(mmctx->iu.ue_ctx, NULL);
}
#endif
mmctx_timer_stop(mmctx, 3350);
mmctx->t3350_mode = GMM_T3350_MODE_NONE;
mmctx->p_tmsi_old = 0;
mmctx->pending_req = 0;
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_ATTACH_SUCCESS, NULL);
switch(mmctx->ran_type) {
case MM_CTX_T_UTRAN_Iu:
osmo_fsm_inst_dispatch(mmctx->iu.mm_state_fsm, E_PMM_PS_ATTACH, NULL);
break;
case 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, TLLI_UNASSIGNED,
mmctx->gb.tlli_new);
osmo_fsm_inst_dispatch(mmctx->gb.mm_state_fsm, E_MM_GPRS_ATTACH, NULL);
break;
}
osmo_fsm_inst_dispatch(mmctx->gmm_att_req.fsm, E_ATTACH_COMPLETE_RECV, 0);
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = mmctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_ATTACH, &sig_data);
return 0;
}
/* Checks if two attach request contain the IEs and IE values
* return 0 if equal
* return -1 if error
* return 1 if unequal
*
* Only do a simple memcmp for now.
*/
int gprs_gmm_attach_req_ies(struct msgb *a, struct msgb *b)
{
struct gsm48_hdr *gh_a = (struct gsm48_hdr *) msgb_gmmh(a);
struct gsm48_hdr *gh_b = (struct gsm48_hdr *) msgb_gmmh(b);
#define GMM_ATTACH_REQ_LEN 26
/* there is the LLC FCS behind */
if (msgb_l3len(a) < GMM_ATTACH_REQ_LEN || msgb_l3len(b) < GMM_ATTACH_REQ_LEN)
return -1;
return !!memcmp(gh_a, gh_b, GMM_ATTACH_REQ_LEN);
}
/* 3GPP TS 24.008 § 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(rate_ctr_group_get_ctr(sgsn->rate_ctrs, 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, "GMM 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;
unsigned long t;
#ifdef PTMSI_ALLOC
uint8_t *l;
int rc;
struct osmo_mobile_identity mi;
#endif
rate_ctr_inc(rate_ctr_group_get_ctr(sgsn->rate_ctrs, CTR_GPRS_ROUTING_AREA_ACKED));
LOGMMCTXP(LOGL_INFO, mm, "<- GMM 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 */
t = osmo_tdef_get(sgsn->cfg.T_defs, 3312, OSMO_TDEF_S, -1);
rua->ra_upd_timer = gprs_secs_to_tmr_floor(t);
gsm48_encode_ra(&rua->ra_id, &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 */
mi = (struct osmo_mobile_identity){
.type = GSM_MI_TYPE_TMSI,
.tmsi = mm->p_tmsi,
};
l = msgb_tl_put(msg, GSM48_IE_GMM_ALLOC_PTMSI);
rc = osmo_mobile_identity_encode_msgb(msg, &mi, false);
if (rc < 0) {
msgb_free(msg);
return -EINVAL;
}
*l = rc;
#endif
/* Optional: Negotiated READY timer value */
t = osmo_tdef_get(sgsn->cfg.T_defs, 3314, OSMO_TDEF_S, -1);
msgb_tv_put(msg, GSM48_IE_GMM_TIMER_READY, gprs_secs_to_tmr_floor(t));
/* Option: MS ID, ... */
return gsm48_gmm_sendmsg(msg, 0, mm, true);
}
/* Chapter 9.4.17: Routing area update reject */
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(rate_ctr_group_get_ctr(sgsn->rate_ctrs, 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) {
bool inactive = (pdp->nsapi < 8) ?
!(pdp_status[0] & (1 << pdp->nsapi)) :
!(pdp_status[1] & (1 << (pdp->nsapi - 8)));
if (!inactive)
continue;
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]);
if (pdp->ggsn)
sgsn_delete_pdp_ctx(pdp);
else /* GTP side already detached, freeing */
sgsn_pdp_ctx_free(pdp);
}
}
/* 3GPP TS 24.008 § 4.7.13.4 Service request procedure not accepted by the
* network. Returns true if MS has active PDP contexts in pdp_status */
bool pdp_status_has_active_nsapis(const uint8_t *pdp_status, const size_t pdp_status_len)
{
size_t i;
for (i = 0; i < pdp_status_len; i++)
if (pdp_status[i] != 0)
return true;
return false;
}
/* 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.
* The follow-on request can be signaled in an Attach Request on IuPS.
* This means the MS/UE asks to keep the PS connection open for further requests
* after the Attach Request succeed.
* The SGSN can decide if it close the connection or not. Both are spec conform. */
/* Update Type 10.5.5.18 */
upd_type = *cur++ & 0x07;
rate_ctr_inc(rate_ctr_group_get_ctr(sgsn->rate_ctrs, CTR_GPRS_ROUTING_AREA_REQUEST));
LOGMMCTXP(LOGL_INFO, mmctx, "-> 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) {
LOGMMCTXP(LOGL_ERROR, mmctx,
"Rejecting GMM RA Update Request: MS Radio Access Capability too long"
" (ms_ra_acc_cap_len = %u > 52)\n", ms_ra_acc_cap_len);
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:
LOGMMCTXP(LOGL_NOTICE, mmctx, "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 */
if (!MSG_IU_UE_CTX(msg)) {
/* Gb */
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 */
struct osmo_mobile_identity mi;
if (osmo_mobile_identity_decode(&mi, TLVP_VAL(&tp, GSM48_IE_GMM_ALLOC_PTMSI),
TLVP_LEN(&tp, GSM48_IE_GMM_ALLOC_PTMSI), false)
|| mi.type != GSM_MI_TYPE_TMSI) {
LOGIUP(MSG_IU_UE_CTX(msg), LOGL_ERROR, "Cannot decode P-TMSI\n");
goto rejected;
}
mmctx = sgsn_mm_ctx_by_ptmsi(mi.tmsi);
#else
LOGIUP(MSG_IU_UE_CTX(msg), LOGL_ERROR,
"Rejecting GMM RA Update Request: No Iu support\n");
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: %s\n",
msgb_tlli(msg),
mmctx->p_tmsi, mmctx->p_tmsi_old,
mmctx->gb.tlli, mmctx->gb.tlli_new,
osmo_rai_name(&mmctx->ra));
/* A RAT change will trigger the common procedure
* below after handling the RAT change. Protect it
* here from being called twice */
if (!mmctx_did_rat_change(mmctx, msg))
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_COMMON_PROC_INIT_REQ, NULL);
}
} else if (!gprs_ra_id_equals(&mmctx->ra, &old_ra_id) ||
mmctx->gmm_fsm->state == ST_GMM_DEREGISTERED)
{
/* We've received either a RAU for a MS which isn't registered
* or a RAU with an unknown RA ID. As long the SGSN doesn't support
* PS handover we treat this as invalid RAU */
struct gprs_ra_id new_ra_id;
char new_ra[32];
bssgp_parse_cell_id(&new_ra_id, msgb_bcid(msg));
osmo_rai_name_buf(new_ra, sizeof(new_ra), &new_ra_id);
if (mmctx->gmm_fsm->state == ST_GMM_DEREGISTERED)
LOGMMCTXP(LOGL_INFO, mmctx,
"Rejecting RAU - GMM state is deregistered. Old RA: %s New RA: %s\n",
osmo_rai_name(&old_ra_id), new_ra);
else
LOGMMCTXP(LOGL_INFO, mmctx,
"Rejecting RAU - Old RA doesn't match MM. Old RA: %s New RA: %s\n",
osmo_rai_name(&old_ra_id), new_ra);
reject_cause = GMM_CAUSE_IMPL_DETACHED;
goto rejected;
}
if (!mmctx) {
if (llme) {
/* send a XID reset to re-set all LLC sequence numbers
* in the MS */
LOGGBP(llme, DMM, LOGL_NOTICE, "LLC XID RESET\n");
gprs_llgmm_reset_oldmsg(msg, GPRS_SAPI_GMM, 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 */
LOGGBIUP(llme, msg, LOGL_ERROR, "Rejecting GMM RA Update Request: MS should GMM Attach first\n");
reject_cause = GMM_CAUSE_IMPL_DETACHED;
goto rejected;
}
if (mmctx_did_rat_change(mmctx, msg)) {
mmctx_handle_rat_change(mmctx, msg, llme);
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_COMMON_PROC_INIT_REQ, NULL);
}
/* 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(rate_ctr_group_get_ctr(mmctx->ctrg, GMM_CTR_PKTS_SIG_IN));
/* Update the MM context with the new RA-ID */
if (mmctx->ran_type == MM_CTX_T_GERAN_Gb && msgb_bcid(msg)) {
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(rate_ctr_group_get_ctr(mmctx->ctrg, GMM_CTR_RA_UPDATE));
#ifdef PTMSI_ALLOC
ptmsi_update(mmctx);
/* Start T3350 and re-transmit up to 5 times until ATTACH COMPLETE */
mmctx->t3350_mode = GMM_T3350_MODE_RAU;
mmctx_timer_start(mmctx, 3350);
#else
/* Make sure we are NORMAL (i.e. not SUSPENDED anymore) */
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_ATTACH_SUCCESS, NULL);
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 accepting the old one during Rx */
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, "GMM RA UPDATE REJ");
else if (llme)
gprs_llgmm_unassign(llme);
#ifdef BUILD_IU
else if (MSG_IU_UE_CTX(msg)) {
unsigned long X1001 = osmo_tdef_get(sgsn->cfg.T_defs, -1001, OSMO_TDEF_S, -1);
ranap_iu_tx_release_free(MSG_IU_UE_CTX(msg), NULL, (int) X1001);
}
#endif
return rc;
}
/* 3GPP TS 24.008 § 9.4.16: Routing area update complete */
static int gsm48_rx_gmm_ra_upd_compl(struct sgsn_mm_ctx *mmctx)
{
struct sgsn_signal_data sig_data;
/* 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;
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_COMMON_PROC_SUCCESS, NULL);
switch(mmctx->ran_type) {
case MM_CTX_T_UTRAN_Iu:
osmo_fsm_inst_dispatch(mmctx->iu.mm_state_fsm, E_PMM_RA_UPDATE, NULL);
break;
case MM_CTX_T_GERAN_Gb:
/* Unassign the old TLLI */
mmctx->gb.tlli = mmctx->gb.tlli_new;
gprs_llgmm_assign(mmctx->gb.llme, TLLI_UNASSIGNED,
mmctx->gb.tlli_new);
osmo_fsm_inst_dispatch(mmctx->gb.mm_state_fsm, E_MM_RA_UPDATE, NULL);
break;
}
memset(&sig_data, 0, sizeof(sig_data));
sig_data.mm = mmctx;
osmo_signal_dispatch(SS_SGSN, S_SGSN_UPDATE, &sig_data);
return 0;
}
/* 3GPP TS 24.008 § 9.4.8: P-TMSI reallocation complete */
static int gsm48_rx_gmm_ptmsi_reall_compl(struct sgsn_mm_ctx *mmctx)
{
LOGMMCTXP(LOGL_INFO, mmctx, "-> PTMSI REALLOCATION 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, TLLI_UNASSIGNED, mmctx->gb.tlli_new, GPRS_ALGO_GEA0, NULL);
}
return 0;
}
/* 3GPP TS 24.008 § 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_data;
uint8_t service_type, mi_len;
struct tlv_parsed tp;
struct osmo_mobile_identity mi;
char mi_log_string[32];
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_IU_UE_CTX(msg)) {
LOGPC(DMM, LOGL_INFO, "Invalid if not in Iu mode\n");
return -1;
}
/* Skip Ciphering key sequence number 10.5.1.2 */
/* uint8_t 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_data = cur;
cur += mi_len;
rc = osmo_mobile_identity_decode(&mi, mi_data, mi_len, false);
if (rc)
goto err_inval;
osmo_mobile_identity_to_str_buf(mi_log_string, sizeof(mi_log_string), &mi);
DEBUGPC(DMM, "MI(%s) type=\"%s\" ", mi_log_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.imsi);
if (!ctx) {
/* FIXME: We need to have a context for service request? */
reject_cause = GMM_CAUSE_IMPL_DETACHED;
goto rejected;
}
msgid2mmctx(ctx, msg);
break;
case GSM_MI_TYPE_TMSI:
/* Try to find MM context based on P-TMSI */
if (!ctx)
ctx = sgsn_mm_ctx_by_ptmsi(mi.tmsi);
if (!ctx) {
/* FIXME: We need to have a context for service request? */
reject_cause = GMM_CAUSE_IMPL_DETACHED;
goto rejected;
}
msgid2mmctx(ctx, msg);
break;
default:
LOGMMCTXP(LOGL_NOTICE, ctx, "Rejecting SERVICE REQUEST with "
"MI %s\n", mi_log_string);
reject_cause = GMM_CAUSE_MS_ID_NOT_DERIVED;
goto rejected;
}
osmo_fsm_inst_dispatch(ctx->gmm_fsm, E_GMM_COMMON_PROC_INIT_REQ, NULL);
ctx->iu.service.type = service_type;
/* 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);
const size_t pdp_status_len = TLVP_LEN(&tp, GSM48_IE_GMM_PDP_CTX_STATUS);
process_ms_ctx_status(ctx, pdp_status);
/* 3GPP TS 24.008 § 4.7.13.4 Service request procedure not
* accepted by the network. Cause #40. If MS has PDP Contexts in
* Active state in pdp_status but there is no PDP contexts on
* SGSN side then Reject with the cause will force the mobile to
* reset PDP contexts */
if (llist_empty(&ctx->pdp_list) && pdp_status_has_active_nsapis(pdp_status, pdp_status_len)) {
reject_cause = GMM_CAUSE_NO_PDP_ACTIVATED;
goto rejected;
}
}
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, "-> GMM STATUS (cause: %s)\n",
get_value_string(gsm48_gmm_cause_names, gh->data[0]));
return 0;
}
/* Rx GPRS Mobility Management. MMCTX can be NULL when called. On !Gb (Iu), llme is NULL */
int gsm0408_rcv_gmm(struct sgsn_mm_ctx *mmctx, struct msgb *msg,
struct gprs_llc_llme *llme, bool drop_cipherable)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_gmmh(msg);
int rc;
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) {
LOGGBP(llme, 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);
/* Don't reply to deatch requests, reason power off */
if (gh->msg_type == GSM48_MT_GMM_DETACH_REQ &&
gh->data[0] & 0x8) {
return 0;
}
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;
}
/* A RAT change is only expected/allowed for RAU/Attach Req */
if (mmctx && mmctx_did_rat_change(mmctx, msg)) {
switch (gh->msg_type) {
case GSM48_MT_GMM_RA_UPD_REQ:
case GSM48_MT_GMM_ATTACH_REQ:
break;
default:
/* This shouldn't happen with other message types and
* we need to error out to prevent a crash */
LOGMMCTXP(LOGL_NOTICE, mmctx, "Dropping GMM %s which was received on different "
"RAT (mmctx ran_type=%u, msg_iu_ue_ctx=%p\n",
get_value_string(gprs_msgt_gmm_names, gh->msg_type),
mmctx->ran_type, MSG_IU_UE_CTX(msg));
return -EINVAL;
}
}
/*
* 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, "GMM DETACH ACK");
rc = 0;
break;
case GSM48_MT_GMM_ATTACH_COMPL:
if (!mmctx)
goto null_mmctx;
rc = gsm48_rx_gmm_att_compl(mmctx);
break;
case GSM48_MT_GMM_RA_UPD_COMPL:
if (!mmctx)
goto null_mmctx;
rc = gsm48_rx_gmm_ra_upd_compl(mmctx);
break;
case GSM48_MT_GMM_PTMSI_REALL_COMPL:
if (!mmctx)
goto null_mmctx;
rc = gsm48_rx_gmm_ptmsi_reall_compl(mmctx);
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:
LOGGBIUP(llme, msg, LOGL_ERROR,
"Received GSM 04.08 message type %s,"
" but no MM context available\n",
get_value_string(gprs_msgt_gmm_names, gh->msg_type));
return -EINVAL;
}
static void mmctx_timer_cb(void *_mm)
{
struct sgsn_mm_ctx *mm = _mm;
struct gsm_auth_tuple *at;
int rc;
unsigned long seconds;
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;
}
seconds = osmo_tdef_get(sgsn->cfg.T_defs, 3350, OSMO_TDEF_S, -1);
osmo_timer_schedule(&mm->timer, seconds, 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;
rc = gsm48_tx_gmm_auth_ciph_req(mm, &at->vec, at->key_seq, false);
if (rc < 0) {
LOGMMCTXP(LOGL_ERROR, mm, "failed sending Auth. & Ciph. Request: %s \n", strerror(-rc));
} else {
seconds = osmo_tdef_get(sgsn->cfg.T_defs, 3360, OSMO_TDEF_S, -1);
osmo_timer_schedule(&mm->timer, seconds, 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, "GMM ATTACH REJECT (T3370)");
break;
}
/* re-tranmit IDENTITY REQUEST and re-start timer */
gsm48_tx_gmm_id_req(mm, mm->t3370_id_type);
seconds = osmo_tdef_get(sgsn->cfg.T_defs, 3370, OSMO_TDEF_S, -1);
osmo_timer_schedule(&mm->timer, seconds, 0);
break;
default:
LOGMMCTXP(LOGL_ERROR, mm, "timer expired in unknown mode %u\n",
mm->T);
}
}
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;
}
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 (!gmm_fsm_is_registered(mmctx->gmm_fsm)) {
LOGMMCTXP(LOGL_NOTICE, mmctx, "SUSPEND request while state "
"!= REGISTERED (TLLI=%08x)\n", tlli);
return -EINVAL;
}
/* Transition from REGISTERED_NORMAL to REGISTERED_SUSPENDED */
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_SUSPEND, NULL);
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 (!gmm_fsm_is_registered(mmctx->gmm_fsm)) {
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 */
osmo_fsm_inst_dispatch(mmctx->gmm_fsm, E_GMM_RESUME, NULL);
return 0;
}
/* Has to be called whenever any PDU (signaling, data, ...) has been received */
void gprs_gb_recv_pdu(struct sgsn_mm_ctx *mmctx, const struct msgb *msg)
{
msgid2mmctx(mmctx, msg);
if (mmctx->gb.llme)
osmo_fsm_inst_dispatch(mmctx->gb.mm_state_fsm, E_MM_PDU_RECEPTION, NULL);
}
/* 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) {
rate_ctr_inc(rate_ctr_group_get_ctr(mmctx->ctrg, GMM_CTR_PKTS_SIG_IN));
mmctx->gb.llme = llme;
gprs_gb_recv_pdu(mmctx, msg);
}
/* 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;
}
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