cellular-infrastructure
/
osmo-msc
mirror of https://gerrit.osmocom.org/osmo-msc
9
0
Fork 0
Code Issues Releases Wiki Activity
osmo-msc/src/libmsc/gsm_04_08.c

1899 lines
54 KiB
C
Raw Blame History

/* 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) 2008-2016 by Harald Welte <laforge@gnumonks.org>
* (C) 2008-2012 by Holger Hans Peter Freyther <zecke@selfish.org>
*
* 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 <stdbool.h>
#include <errno.h>
#include <time.h>
#include <netinet/in.h>
#include <regex.h>
#include <sys/types.h>
#include "bscconfig.h"
#include <osmocom/msc/db.h>
#include <osmocom/msc/debug.h>
#include <osmocom/msc/gsm_data.h>
#include <osmocom/msc/gsm_subscriber.h>
#include <osmocom/msc/gsm_04_11.h>
#include <osmocom/msc/gsm_04_08.h>
#include <osmocom/msc/gsm_04_80.h>
#include <osmocom/msc/gsm_04_14.h>
#include <osmocom/msc/gsm_09_11.h>
#include <osmocom/msc/signal.h>
#include <osmocom/msc/transaction.h>
#include <osmocom/msc/silent_call.h>
#include <osmocom/msc/mncc_int.h>
#include <osmocom/abis/e1_input.h>
#include <osmocom/core/bitvec.h>
#include <osmocom/msc/vlr.h>
#include <osmocom/msc/msc_ifaces.h>
#include <osmocom/gsm/gsm48.h>
#include <osmocom/gsm/gsm0480.h>
#include <osmocom/gsm/gsm_utils.h>
#include <osmocom/gsm/protocol/gsm_04_08.h>
#include <osmocom/core/msgb.h>
#include <osmocom/core/talloc.h>
#include <osmocom/core/utils.h>
#include <osmocom/core/byteswap.h>
#include <osmocom/gsm/tlv.h>
#include <osmocom/crypt/auth.h>
#ifdef BUILD_IU
#include <osmocom/ranap/iu_client.h>
#endif
#include <osmocom/msc/msc_ifaces.h>
#include <osmocom/msc/a_iface.h>
#include <osmocom/msc/msc_mgcp.h>
#include <assert.h>
void *tall_locop_ctx;
void *tall_authciphop_ctx;
static int gsm0408_loc_upd_acc(struct ran_conn *conn,
uint32_t send_tmsi);
/*! Send a simple GSM 04.08 message without any payload
* \param conn Active RAN connection
* \param[in] pdisc Protocol discriminator
* \param[in] msg_type Message type
* \return result of \ref gsm48_conn_sendmsg
*/
int gsm48_tx_simple(struct ran_conn *conn,
uint8_t pdisc, uint8_t msg_type)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 TX SIMPLE");
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = pdisc;
gh->msg_type = msg_type;
return gsm48_conn_sendmsg(msg, conn, NULL);
}
static bool classmark1_is_r99(const struct gsm48_classmark1 *cm1)
{
return cm1->rev_lev >= 2;
}
static bool classmark2_is_r99(const uint8_t *cm2, uint8_t cm2_len)
{
uint8_t rev_lev;
if (!cm2_len)
return false;
rev_lev = (cm2[0] >> 5) & 0x3;
return rev_lev >= 2;
}
static bool classmark_is_r99(struct gsm_classmark *cm)
{
if (cm->classmark1_set)
return classmark1_is_r99(&cm->classmark1);
return classmark2_is_r99(cm->classmark2, cm->classmark2_len);
}
/* Determine if the given CLASSMARK (1/2/3) value permits a given A5/n cipher.
* Return 1 when the given A5/n is permitted, 0 when not, and negative if the respective MS CLASSMARK is
* not known, where the negative number indicates the classmark type: -2 means Classmark 2 is not
* available. */
static int classmark_supports_a5(const struct gsm_classmark *cm, uint8_t a5)
{
switch (a5) {
case 0:
/* all phones must implement A5/0, see 3GPP TS 43.020 4.9 */
return 1;
case 1:
/* 3GPP TS 43.020 4.9 requires A5/1 to be suppored by all phones and actually states:
* "The network shall not provide service to an MS which indicates that it does not
* support the ciphering algorithm A5/1.". However, let's be more tolerant based
* on policy here */
/* See 3GPP TS 24.008 10.5.1.7 */
if (!cm->classmark1_set) {
DEBUGP(DMSC, "CLASSMARK 1 unknown, assuming MS supports A5/1\n");
return -1;
} else {
if (cm->classmark1.a5_1)
return 0; /* Inverted logic for this bit! */
else
return 1;
}
break;
case 2:
case 3:
/* See 3GPP TS 24.008 10.5.1.6 */
if (cm->classmark2_len < 3) {
return -2;
} else {
if (cm->classmark2[2] & (1 << (a5-2)))
return 1;
else
return 0;
}
break;
case 4:
case 5:
case 6:
case 7:
/* See 3GPP TS 24.008 10.5.1.7 */
if (cm->classmark3_len < 1) {
return -3;
} else {
if (cm->classmark3[0] & (1 << (a5-4)))
return 1;
else
return 0;
}
break;
default:
return false;
}
}
int gsm48_conn_sendmsg(struct msgb *msg, struct ran_conn *conn, struct gsm_trans *trans)
{
struct gsm48_hdr *gh = (struct gsm48_hdr *) msg->data;
/* if we get passed a transaction reference, do some common
* work that the caller no longer has to do */
if (trans) {
gh->proto_discr = trans->protocol | (trans->transaction_id << 4);
OMSC_LINKID_CB(msg) = trans->dlci;
}
return msc_tx_dtap(conn, msg);
}
/* clear all transactions globally; used in case of MNCC socket disconnect */
void gsm0408_clear_all_trans(struct gsm_network *net, int protocol)
{
struct gsm_trans *trans, *temp;
LOGP(DCC, LOGL_NOTICE, "Clearing all currently active transactions!!!\n");
llist_for_each_entry_safe(trans, temp, &net->trans_list, entry) {
if (trans->protocol == protocol) {
trans->callref = 0;
trans_free(trans);
}
}
}
/* Chapter 9.2.14 : Send LOCATION UPDATING REJECT */
static int gsm0408_loc_upd_rej(struct ran_conn *conn, uint8_t cause)
{
struct msgb *msg;
msg = gsm48_create_loc_upd_rej(cause);
if (!msg) {
LOGP(DMM, LOGL_ERROR, "Failed to create msg for LOCATION UPDATING REJECT.\n");
return -1;
}
LOGP(DMM, LOGL_INFO, "Subscriber %s: LOCATION UPDATING REJECT\n",
vlr_subscr_name(conn->vsub));
return gsm48_conn_sendmsg(msg, conn, NULL);
}
/* Chapter 9.2.13 : Send LOCATION UPDATE ACCEPT */
static int gsm0408_loc_upd_acc(struct ran_conn *conn,
uint32_t send_tmsi)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 LOC UPD ACC");
struct gsm48_hdr *gh;
struct gsm48_loc_area_id *lai;
uint8_t *mid;
struct osmo_location_area_id laid = {
.plmn = conn->network->plmn,
.lac = conn->lac,
};
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_MM;
gh->msg_type = GSM48_MT_MM_LOC_UPD_ACCEPT;
lai = (struct gsm48_loc_area_id *) msgb_put(msg, sizeof(*lai));
gsm48_generate_lai2(lai, &laid);
if (send_tmsi == GSM_RESERVED_TMSI) {
/* we did not allocate a TMSI to the MS, so we need to
* include the IMSI in order for the MS to delete any
* old TMSI that might still be allocated */
uint8_t mi[10];
int len;
len = gsm48_generate_mid_from_imsi(mi, conn->vsub->imsi);
mid = msgb_put(msg, len);
memcpy(mid, mi, len);
DEBUGP(DMM, "-> %s LOCATION UPDATE ACCEPT\n",
vlr_subscr_name(conn->vsub));
} else {
/* Include the TMSI, which means that the MS will send a
* TMSI REALLOCATION COMPLETE, and we should wait for
* that until T3250 expiration */
mid = msgb_put(msg, GSM48_MID_TMSI_LEN);
gsm48_generate_mid_from_tmsi(mid, send_tmsi);
DEBUGP(DMM, "-> %s LOCATION UPDATE ACCEPT (TMSI = 0x%08x)\n",
vlr_subscr_name(conn->vsub),
send_tmsi);
}
/* TODO: Follow-on proceed */
/* TODO: CTS permission */
/* TODO: Equivalent PLMNs */
/* TODO: Emergency Number List */
/* TODO: Per-MS T3312 */
return gsm48_conn_sendmsg(msg, conn, NULL);
}
/* Transmit Chapter 9.2.10 Identity Request */
static int mm_tx_identity_req(struct ran_conn *conn, uint8_t id_type)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 ID REQ");
struct gsm48_hdr *gh;
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
gh->proto_discr = GSM48_PDISC_MM;
gh->msg_type = GSM48_MT_MM_ID_REQ;
gh->data[0] = id_type;
return gsm48_conn_sendmsg(msg, conn, NULL);
}
/* Parse Chapter 9.2.11 Identity Response */
static int mm_rx_id_resp(struct ran_conn *conn, struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
uint8_t mi_type = gh->data[1] & GSM_MI_TYPE_MASK;
char mi_string[GSM48_MI_SIZE];
if (!conn->vsub) {
LOGP(DMM, LOGL_ERROR,
"Rx MM Identity Response: invalid: no subscriber\n");
return -EINVAL;
}
gsm48_mi_to_string(mi_string, sizeof(mi_string), &gh->data[1], gh->data[0]);
DEBUGP(DMM, "IDENTITY RESPONSE: MI(%s)=%s\n",
gsm48_mi_type_name(mi_type), mi_string);
osmo_signal_dispatch(SS_SUBSCR, S_SUBSCR_IDENTITY, gh->data);
return vlr_subscr_rx_id_resp(conn->vsub, gh->data+1, gh->data[0]);
}
/* Chapter 9.2.15: Receive Location Updating Request.
* Keep this function non-static for direct invocation by unit tests. */
int mm_rx_loc_upd_req(struct ran_conn *conn, struct msgb *msg)
{
struct gsm_network *net = conn->network;
struct gsm48_hdr *gh = msgb_l3(msg);
struct gsm48_loc_upd_req *lu;
uint8_t mi_type;
char mi_string[GSM48_MI_SIZE];
enum vlr_lu_type vlr_lu_type = VLR_LU_TYPE_REGULAR;
uint32_t tmsi;
char *imsi;
struct osmo_location_area_id old_lai, new_lai;
struct osmo_fsm_inst *lu_fsm;
bool is_utran;
lu = (struct gsm48_loc_upd_req *) gh->data;
if (ran_conn_is_establishing_auth_ciph(conn)) {
LOG_RAN_CONN_CAT(conn, DMM, LOGL_ERROR,
"Cannot accept another LU, conn already busy establishing authenticity;"
" extraneous LOCATION UPDATING REQUEST: MI=%s LU-type=%s\n",
osmo_mi_name(lu->mi, lu->mi_len), osmo_lu_type_name(lu->type));
return -EINVAL;
}
if (ran_conn_is_accepted(conn)) {
LOG_RAN_CONN_CAT(conn, DMM, LOGL_ERROR,
"Cannot accept another LU, conn already established;"
" extraneous LOCATION UPDATING REQUEST: MI=%s LU-type=%s\n",
osmo_mi_name(lu->mi, lu->mi_len), osmo_lu_type_name(lu->type));
return -EINVAL;
}
conn->complete_layer3_type = COMPLETE_LAYER3_LU;
ran_conn_update_id_from_mi(conn, lu->mi, lu->mi_len);
LOG_RAN_CONN_CAT(conn, DMM, LOGL_DEBUG, "LOCATION UPDATING REQUEST: MI=%s LU-type=%s\n",
osmo_mi_name(lu->mi, lu->mi_len), osmo_lu_type_name(lu->type));
osmo_signal_dispatch(SS_SUBSCR, S_SUBSCR_IDENTITY, &lu->mi_len);
switch (lu->type) {
case GSM48_LUPD_NORMAL:
rate_ctr_inc(&conn->network->msc_ctrs->ctr[MSC_CTR_LOC_UPDATE_TYPE_NORMAL]);
vlr_lu_type = VLR_LU_TYPE_REGULAR;
break;
case GSM48_LUPD_IMSI_ATT:
rate_ctr_inc(&conn->network->msc_ctrs->ctr[MSC_CTR_LOC_UPDATE_TYPE_ATTACH]);
vlr_lu_type = VLR_LU_TYPE_IMSI_ATTACH;
break;
case GSM48_LUPD_PERIODIC:
rate_ctr_inc(&conn->network->msc_ctrs->ctr[MSC_CTR_LOC_UPDATE_TYPE_PERIODIC]);
vlr_lu_type = VLR_LU_TYPE_PERIODIC;
break;
}
/* TODO: 10.5.1.6 MS Classmark for UMTS / Classmark 2 */
/* TODO: 10.5.3.14 Aditional update parameters (CS fallback calls) */
/* TODO: 10.5.7.8 Device properties */
/* TODO: 10.5.1.15 MS network feature support */
mi_type = lu->mi[0] & GSM_MI_TYPE_MASK;
gsm48_mi_to_string(mi_string, sizeof(mi_string), lu->mi, lu->mi_len);
switch (mi_type) {
case GSM_MI_TYPE_IMSI:
tmsi = GSM_RESERVED_TMSI;
imsi = mi_string;
break;
case GSM_MI_TYPE_TMSI:
tmsi = tmsi_from_string(mi_string);
imsi = NULL;
break;
default:
LOG_RAN_CONN_CAT(conn, DMM, LOGL_ERROR, "unknown mobile identity type\n");
tmsi = GSM_RESERVED_TMSI;
imsi = NULL;
break;
}
gsm48_decode_lai2(&lu->lai, &old_lai);
new_lai.plmn = conn->network->plmn;
new_lai.lac = conn->lac;
LOG_RAN_CONN_CAT(conn, DMM, LOGL_DEBUG, "LU/new-LAC: %u/%u\n", old_lai.lac, new_lai.lac);
is_utran = (conn->via_ran == OSMO_RAT_UTRAN_IU);
lu_fsm = vlr_loc_update(conn->fi,
RAN_CONN_E_ACCEPTED, RAN_CONN_E_CN_CLOSE, NULL,
net->vlr, conn, vlr_lu_type, tmsi, imsi,
&old_lai, &new_lai,
is_utran || conn->network->authentication_required,
is_utran || conn->network->a5_encryption_mask > 0x01,
classmark1_is_r99(&lu->classmark1),
is_utran,
net->vlr->cfg.assign_tmsi);
if (!lu_fsm) {
LOG_RAN_CONN(conn, LOGL_ERROR, "Can't start LU FSM\n");
return 0;
}
/* From vlr_loc_update() we expect an implicit dispatch of
* VLR_ULA_E_UPDATE_LA, and thus we expect msc_vlr_subscr_assoc() to
* already have been called and completed. Has an error occured? */
if (!conn->vsub || conn->vsub->lu_fsm != lu_fsm) {
LOG_RAN_CONN(conn, LOGL_ERROR, "internal error during Location Updating attempt\n");
return -EIO;
}
conn->vsub->classmark.classmark1 = lu->classmark1;
conn->vsub->classmark.classmark1_set = true;
ran_conn_complete_layer_3(conn);
return 0;
}
/* Turn int into semi-octet representation: 98 => 0x89 */
/* FIXME: libosmocore/libosmogsm */
static uint8_t bcdify(uint8_t value)
{
uint8_t ret;
ret = value / 10;
ret |= (value % 10) << 4;
return ret;
}
/* Section 9.2.15a */
int gsm48_tx_mm_info(struct ran_conn *conn)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 MM INF");
struct gsm48_hdr *gh;
struct gsm_network *net = conn->network;
uint8_t *ptr8;
int name_len, name_pad;
time_t cur_t;
struct tm* gmt_time;
struct tm* local_time;
int tzunits;
int dst = 0;
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
gh->proto_discr = GSM48_PDISC_MM;
gh->msg_type = GSM48_MT_MM_INFO;
if (net->name_long) {
#if 0
name_len = strlen(net->name_long);
/* 10.5.3.5a */
ptr8 = msgb_put(msg, 3);
ptr8[0] = GSM48_IE_NAME_LONG;
ptr8[1] = name_len*2 +1;
ptr8[2] = 0x90; /* UCS2, no spare bits, no CI */
ptr16 = (uint16_t *) msgb_put(msg, name_len*2);
for (i = 0; i < name_len; i++)
ptr16[i] = htons(net->name_long[i]);
/* FIXME: Use Cell Broadcast, not UCS-2, since
* UCS-2 is only supported by later revisions of the spec */
#endif
name_len = (strlen(net->name_long)*7)/8;
name_pad = (8 - strlen(net->name_long)*7)%8;
if (name_pad > 0)
name_len++;
/* 10.5.3.5a */
ptr8 = msgb_put(msg, 3);
ptr8[0] = GSM48_IE_NAME_LONG;
ptr8[1] = name_len +1;
ptr8[2] = 0x80 | name_pad; /* Cell Broadcast DCS, no CI */
ptr8 = msgb_put(msg, name_len);
gsm_7bit_encode_n(ptr8, name_len, net->name_long, NULL);
}
if (net->name_short) {
#if 0
name_len = strlen(net->name_short);
/* 10.5.3.5a */
ptr8 = (uint8_t *) msgb_put(msg, 3);
ptr8[0] = GSM48_IE_NAME_SHORT;
ptr8[1] = name_len*2 + 1;
ptr8[2] = 0x90; /* UCS2, no spare bits, no CI */
ptr16 = (uint16_t *) msgb_put(msg, name_len*2);
for (i = 0; i < name_len; i++)
ptr16[i] = htons(net->name_short[i]);
#endif
name_len = (strlen(net->name_short)*7)/8;
name_pad = (8 - strlen(net->name_short)*7)%8;
if (name_pad > 0)
name_len++;
/* 10.5.3.5a */
ptr8 = (uint8_t *) msgb_put(msg, 3);
ptr8[0] = GSM48_IE_NAME_SHORT;
ptr8[1] = name_len +1;
ptr8[2] = 0x80 | name_pad; /* Cell Broadcast DCS, no CI */
ptr8 = msgb_put(msg, name_len);
gsm_7bit_encode_n(ptr8, name_len, net->name_short, NULL);
}
/* Section 10.5.3.9 */
cur_t = time(NULL);
gmt_time = gmtime(&cur_t);
ptr8 = msgb_put(msg, 8);
ptr8[0] = GSM48_IE_NET_TIME_TZ;
ptr8[1] = bcdify(gmt_time->tm_year % 100);
ptr8[2] = bcdify(gmt_time->tm_mon + 1);
ptr8[3] = bcdify(gmt_time->tm_mday);
ptr8[4] = bcdify(gmt_time->tm_hour);
ptr8[5] = bcdify(gmt_time->tm_min);
ptr8[6] = bcdify(gmt_time->tm_sec);
if (net->tz.override) {
/* Convert tz.hr and tz.mn to units */
if (net->tz.hr < 0) {
tzunits = ((net->tz.hr/-1)*4);
tzunits = tzunits + (net->tz.mn/15);
ptr8[7] = bcdify(tzunits);
/* Set negative time */
ptr8[7] |= 0x08;
}
else {
tzunits = net->tz.hr*4;
tzunits = tzunits + (net->tz.mn/15);
ptr8[7] = bcdify(tzunits);
}
/* Convert DST value */
if (net->tz.dst >= 0 && net->tz.dst <= 2)
dst = net->tz.dst;
}
else {
/* Need to get GSM offset and convert into 15 min units */
/* This probably breaks if gmtoff returns a value not evenly divisible by 15? */
#ifdef HAVE_TM_GMTOFF_IN_TM
local_time = localtime(&cur_t);
tzunits = (local_time->tm_gmtoff/60)/15;
#else
/* find timezone offset */
time_t utc;
double offsetFromUTC;
utc = mktime(gmt_time);
local_time = localtime(&cur_t);
offsetFromUTC = difftime(cur_t, utc);
if (local_time->tm_isdst)
offsetFromUTC += 3600.0;
tzunits = ((int)offsetFromUTC) / 60 / 15;
#endif
if (tzunits < 0) {
tzunits = tzunits/-1;
ptr8[7] = bcdify(tzunits);
/* Flip it to negative */
ptr8[7] |= 0x08;
}
else
ptr8[7] = bcdify(tzunits);
/* Does not support DST +2 */
if (local_time->tm_isdst)
dst = 1;
}
if (dst) {
ptr8 = msgb_put(msg, 3);
ptr8[0] = GSM48_IE_NET_DST;
ptr8[1] = 1;
ptr8[2] = dst;
}
LOG_RAN_CONN(conn, LOGL_DEBUG, "Tx MM INFO\n");
return gsm48_conn_sendmsg(msg, conn, NULL);
}
/*! Send an Authentication Request to MS on the given RAN connection
* according to 3GPP/ETSI TS 24.008, Section 9.2.2.
* \param[in] conn Subscriber connection to send on.
* \param[in] rand Random challenge token to send, must be 16 bytes long.
* \param[in] autn r99: In case of UMTS mutual authentication, AUTN token to
* send; must be 16 bytes long, or pass NULL for plain GSM auth.
* \param[in] key_seq auth tuple's sequence number.
*/
int gsm48_tx_mm_auth_req(struct ran_conn *conn, uint8_t *rand,
uint8_t *autn, int key_seq)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 AUTH REQ");
struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
struct gsm48_auth_req *ar = (struct gsm48_auth_req *) msgb_put(msg, sizeof(*ar));
DEBUGP(DMM, "Tx AUTH REQ (rand = %s)\n", osmo_hexdump_nospc(rand, 16));
if (autn)
DEBUGP(DMM, " AUTH REQ (autn = %s)\n", osmo_hexdump_nospc(autn, 16));
gh->proto_discr = GSM48_PDISC_MM;
gh->msg_type = GSM48_MT_MM_AUTH_REQ;
ar->key_seq = key_seq;
/* 16 bytes RAND parameters */
osmo_static_assert(sizeof(ar->rand) == 16, sizeof_auth_req_r99_rand);
if (rand)
memcpy(ar->rand, rand, 16);
/* 16 bytes AUTN */
if (autn)
msgb_tlv_put(msg, GSM48_IE_AUTN, 16, autn);
return gsm48_conn_sendmsg(msg, conn, NULL);
}
/* Section 9.2.1 */
int gsm48_tx_mm_auth_rej(struct ran_conn *conn)
{
DEBUGP(DMM, "-> AUTH REJECT\n");
return gsm48_tx_simple(conn, GSM48_PDISC_MM, GSM48_MT_MM_AUTH_REJ);
}
static int msc_vlr_tx_cm_serv_acc(void *msc_conn_ref);
static int msc_vlr_tx_cm_serv_rej(void *msc_conn_ref, enum gsm48_reject_value result);
static int cm_serv_reuse_conn(struct ran_conn *conn, const uint8_t *mi_lv)
{
uint8_t mi_type;
char mi_string[GSM48_MI_SIZE];
uint32_t tmsi;
gsm48_mi_to_string(mi_string, sizeof(mi_string), mi_lv+1, mi_lv[0]);
mi_type = mi_lv[1] & GSM_MI_TYPE_MASK;
switch (mi_type) {
case GSM_MI_TYPE_IMSI:
if (vlr_subscr_matches_imsi(conn->vsub, mi_string))
goto accept_reuse;
break;
case GSM_MI_TYPE_TMSI:
tmsi = osmo_load32be(mi_lv+2);
if (vlr_subscr_matches_tmsi(conn->vsub, tmsi))
goto accept_reuse;
break;
case GSM_MI_TYPE_IMEI:
if (vlr_subscr_matches_imei(conn->vsub, mi_string))
goto accept_reuse;
break;
default:
break;
}
LOGP(DMM, LOGL_ERROR, "%s: CM Service Request with mismatching mobile identity: %s %s\n",
vlr_subscr_name(conn->vsub), gsm48_mi_type_name(mi_type), mi_string);
msc_vlr_tx_cm_serv_rej(conn, GSM48_REJECT_ILLEGAL_MS);
return -EINVAL;
accept_reuse:
DEBUGP(DMM, "%s: re-using already accepted connection\n",
vlr_subscr_name(conn->vsub));
if (!conn->received_cm_service_request) {
conn->received_cm_service_request = true;
ran_conn_get(conn, RAN_CONN_USE_CM_SERVICE);
}
ran_conn_update_id(conn);
return conn->network->vlr->ops.tx_cm_serv_acc(conn);
}
/*
* Handle CM Service Requests
* a) Verify that the packet is long enough to contain the information
* we require otherwsie reject with INCORRECT_MESSAGE
* b) Try to parse the TMSI. If we do not have one reject
* c) Check that we know the subscriber with the TMSI otherwise reject
* with a HLR cause
* d) Set the subscriber on the conn and accept
*
* Keep this function non-static for direct invocation by unit tests.
*/
int gsm48_rx_mm_serv_req(struct ran_conn *conn, struct msgb *msg)
{
struct gsm_network *net = conn->network;
uint8_t mi_type;
struct gsm48_hdr *gh = msgb_l3(msg);
struct gsm48_service_request *req =
(struct gsm48_service_request *)gh->data;
/* unfortunately in Phase1 the classmark2 length is variable */
uint8_t classmark2_len = gh->data[1];
uint8_t *classmark2 = gh->data+2;
uint8_t *mi_p = classmark2 + classmark2_len;
uint8_t mi_len = *mi_p;
uint8_t *mi = mi_p + 1;
struct osmo_location_area_id lai;
bool is_utran;
lai.plmn = conn->network->plmn;
lai.lac = conn->lac;
if (msg->data_len < sizeof(struct gsm48_service_request*)) {
LOG_RAN_CONN(conn, LOGL_ERROR, "Rx CM SERVICE REQUEST: wrong message size (%u < %zu)\n",
msg->data_len, sizeof(struct gsm48_service_request*));
return msc_gsm48_tx_mm_serv_rej(conn,
GSM48_REJECT_INCORRECT_MESSAGE);
}
if (msg->data_len < req->mi_len + 6) {
LOG_RAN_CONN(conn, LOGL_ERROR, "Rx CM SERVICE REQUEST: message does not fit in packet\n");
return msc_gsm48_tx_mm_serv_rej(conn,
GSM48_REJECT_INCORRECT_MESSAGE);
}
if (ran_conn_is_establishing_auth_ciph(conn)) {
LOG_RAN_CONN(conn, LOGL_ERROR,
"Cannot accept CM Service Request, conn already busy establishing authenticity\n");
msc_vlr_tx_cm_serv_rej(conn, GSM48_REJECT_CONGESTION);
return -EINVAL;
/* or should we accept and note down the service request anyway? */
}
conn->complete_layer3_type = COMPLETE_LAYER3_CM_SERVICE_REQ;
ran_conn_update_id_from_mi(conn, mi, mi_len);
LOG_RAN_CONN_CAT(conn, DMM, LOGL_DEBUG, "Rx CM SERVICE REQUEST cm_service_type=0x%02x\n",
req->cm_service_type);
mi_type = (mi && mi_len) ? (mi[0] & GSM_MI_TYPE_MASK) : GSM_MI_TYPE_NONE;
switch (mi_type) {
case GSM_MI_TYPE_IMSI:
case GSM_MI_TYPE_TMSI:
/* continue below */
break;
case GSM_MI_TYPE_IMEI:
if (req->cm_service_type == GSM48_CMSERV_EMERGENCY) {
/* We don't do emergency calls by IMEI */
LOG_RAN_CONN(conn, LOGL_NOTICE, "Tx CM SERVICE REQUEST REJECT\n");
return msc_gsm48_tx_mm_serv_rej(conn, GSM48_REJECT_IMEI_NOT_ACCEPTED);
}
/* fall-through for non-emergency setup */
default:
LOG_RAN_CONN(conn, LOGL_ERROR, "MI type is not expected: %s\n", gsm48_mi_type_name(mi_type));
return msc_gsm48_tx_mm_serv_rej(conn,
GSM48_REJECT_INCORRECT_MESSAGE);
}
switch (req->cm_service_type) {
case GSM48_CMSERV_MO_CALL_PACKET:
case GSM48_CMSERV_EMERGENCY:
case GSM48_CMSERV_SMS:
case GSM48_CMSERV_SUP_SERV:
/* continue below */
break;
default:
return msc_gsm48_tx_mm_serv_rej(conn, GSM48_REJECT_SRV_OPT_NOT_SUPPORTED);
}
if (ran_conn_is_accepted(conn))
return cm_serv_reuse_conn(conn, mi_p);
osmo_signal_dispatch(SS_SUBSCR, S_SUBSCR_IDENTITY, mi_p);
is_utran = (conn->via_ran == OSMO_RAT_UTRAN_IU);
vlr_proc_acc_req(conn->fi,
RAN_CONN_E_ACCEPTED, RAN_CONN_E_CN_CLOSE, NULL,
net->vlr, conn,
VLR_PR_ARQ_T_CM_SERV_REQ, mi-1, &lai,
is_utran || conn->network->authentication_required,
is_utran || conn->network->a5_encryption_mask > 0x01,
classmark2_is_r99(classmark2, classmark2_len),
is_utran);
/* From vlr_proc_acc_req() we expect an implicit dispatch of PR_ARQ_E_START we expect
* msc_vlr_subscr_assoc() to already have been called and completed. Has an error occured? */
if (!conn->vsub) {
LOG_RAN_CONN(conn, LOGL_ERROR, "subscriber not allowed to do a CM Service Request\n");
return -EIO;
}
memcpy(conn->vsub->classmark.classmark2, classmark2, classmark2_len);
conn->vsub->classmark.classmark2_len = classmark2_len;
ran_conn_complete_layer_3(conn);
return 0;
}
/* Receive a CM Re-establish Request */
static int gsm48_rx_cm_reest_req(struct ran_conn *conn, struct msgb *msg)
{
uint8_t mi_type;
char mi_string[GSM48_MI_SIZE];
struct gsm48_hdr *gh = msgb_l3(msg);
uint8_t classmark2_len = gh->data[1];
uint8_t *classmark2 = gh->data+2;
uint8_t mi_len = *(classmark2 + classmark2_len);
uint8_t *mi = (classmark2 + classmark2_len + 1);
gsm48_mi_to_string(mi_string, sizeof(mi_string), mi, mi_len);
mi_type = mi[0] & GSM_MI_TYPE_MASK;
DEBUGP(DMM, "<- CM RE-ESTABLISH REQUEST MI(%s)=%s\n", gsm48_mi_type_name(mi_type), mi_string);
/* we don't support CM call re-establishment */
return msc_gsm48_tx_mm_serv_rej(conn, GSM48_REJECT_SRV_OPT_NOT_SUPPORTED);
}
static int gsm48_rx_mm_imsi_detach_ind(struct ran_conn *conn, struct msgb *msg)
{
struct gsm_network *network = conn->network;
struct gsm48_hdr *gh = msgb_l3(msg);
struct gsm48_imsi_detach_ind *idi =
(struct gsm48_imsi_detach_ind *) gh->data;
uint8_t mi_type = idi->mi[0] & GSM_MI_TYPE_MASK;
char mi_string[GSM48_MI_SIZE];
struct vlr_subscr *vsub = NULL;
gsm48_mi_to_string(mi_string, sizeof(mi_string), idi->mi, idi->mi_len);
DEBUGP(DMM, "IMSI DETACH INDICATION: MI(%s)=%s\n",
gsm48_mi_type_name(mi_type), mi_string);
rate_ctr_inc(&network->msc_ctrs->ctr[MSC_CTR_LOC_UPDATE_TYPE_DETACH]);
switch (mi_type) {
case GSM_MI_TYPE_TMSI:
vsub = vlr_subscr_find_by_tmsi(network->vlr,
tmsi_from_string(mi_string));
break;
case GSM_MI_TYPE_IMSI:
vsub = vlr_subscr_find_by_imsi(network->vlr, mi_string);
break;
case GSM_MI_TYPE_IMEI:
case GSM_MI_TYPE_IMEISV:
/* no sim card... FIXME: what to do ? */
LOGP(DMM, LOGL_ERROR, "MI(%s)=%s: unimplemented mobile identity type\n",
gsm48_mi_type_name(mi_type), mi_string);
break;
default:
LOGP(DMM, LOGL_ERROR, "MI(%s)=%s: unknown mobile identity type\n",
gsm48_mi_type_name(mi_type), mi_string);
break;
}
if (!vsub) {
LOGP(DMM, LOGL_ERROR, "IMSI DETACH for unknown subscriber MI(%s)=%s\n",
gsm48_mi_type_name(mi_type), mi_string);
} else {
LOGP(DMM, LOGL_INFO, "IMSI DETACH for %s\n", vlr_subscr_name(vsub));
if (vsub->cs.is_paging)
subscr_paging_cancel(vsub, GSM_PAGING_EXPIRED);
/* We already got Classmark 1 during Location Updating ... but well, ok */
vsub->classmark.classmark1 = idi->classmark1;
vlr_subscr_rx_imsi_detach(vsub);
osmo_signal_dispatch(SS_SUBSCR, S_SUBSCR_DETACHED, vsub);
vlr_subscr_put(vsub);
}
ran_conn_close(conn, 0);
return 0;
}
static int gsm48_rx_mm_status(struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
DEBUGP(DMM, "MM STATUS (reject cause 0x%02x)\n", gh->data[0]);
return 0;
}
static int parse_gsm_auth_resp(uint8_t *res, uint8_t *res_len,
struct ran_conn *conn,
struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
struct gsm48_auth_resp *ar = (struct gsm48_auth_resp*) gh->data;
if (msgb_l3len(msg) < sizeof(*gh) + sizeof(*ar)) {
LOGP(DMM, LOGL_ERROR,
"%s: MM AUTHENTICATION RESPONSE:"
" l3 length invalid: %u\n",
vlr_subscr_name(conn->vsub), msgb_l3len(msg));
return -EINVAL;
}
*res_len = sizeof(ar->sres);
memcpy(res, ar->sres, sizeof(ar->sres));
return 0;
}
static int parse_umts_auth_resp(uint8_t *res, uint8_t *res_len,
struct ran_conn *conn,
struct msgb *msg)
{
struct gsm48_hdr *gh;
uint8_t *data;
uint8_t iei;
uint8_t ie_len;
unsigned int data_len;
/* First parse the GSM part */
if (parse_gsm_auth_resp(res, res_len, conn, msg))
return -EINVAL;
OSMO_ASSERT(*res_len == 4);
/* Then add the extended res part */
gh = msgb_l3(msg);
data = gh->data + sizeof(struct gsm48_auth_resp);
data_len = msgb_l3len(msg) - (data - (uint8_t*)msgb_l3(msg));
if (data_len < 3) {
LOGP(DMM, LOGL_ERROR,
"%s: MM AUTHENTICATION RESPONSE:"
" l3 length invalid: %u\n",
vlr_subscr_name(conn->vsub), msgb_l3len(msg));
return -EINVAL;
}
iei = data[0];
ie_len = data[1];
if (iei != GSM48_IE_AUTH_RES_EXT) {
LOGP(DMM, LOGL_ERROR,
"%s: MM R99 AUTHENTICATION RESPONSE:"
" expected IEI 0x%02x, got 0x%02x\n",
vlr_subscr_name(conn->vsub),
GSM48_IE_AUTH_RES_EXT, iei);
return -EINVAL;
}
if (ie_len > 12) {
LOGP(DMM, LOGL_ERROR,
"%s: MM R99 AUTHENTICATION RESPONSE:"
" extended Auth Resp IE 0x%02x is too large: %u bytes\n",
vlr_subscr_name(conn->vsub), GSM48_IE_AUTH_RES_EXT, ie_len);
return -EINVAL;
}
*res_len += ie_len;
memcpy(res + 4, &data[2], ie_len);
return 0;
}
/* Chapter 9.2.3: Authentication Response */
static int gsm48_rx_mm_auth_resp(struct ran_conn *conn, struct msgb *msg)
{
uint8_t res[16];
uint8_t res_len;
int rc;
bool is_umts;
if (!conn->vsub) {
LOGP(DMM, LOGL_ERROR,
"MM AUTHENTICATION RESPONSE: invalid: no subscriber\n");
ran_conn_close(conn, GSM_CAUSE_AUTH_FAILED);
return -EINVAL;
}
is_umts = (msgb_l3len(msg) > sizeof(struct gsm48_hdr) + sizeof(struct gsm48_auth_resp));
if (is_umts)
rc = parse_umts_auth_resp(res, &res_len, conn, msg);
else
rc = parse_gsm_auth_resp(res, &res_len, conn, msg);
if (rc) {
LOGP(DMM, LOGL_ERROR,
"%s: MM AUTHENTICATION RESPONSE: invalid: parsing %s AKA Auth Response"
" failed with rc=%d; dispatching zero length SRES/RES to trigger failure\n",
vlr_subscr_name(conn->vsub), is_umts ? "UMTS" : "GSM", rc);
memset(res, 0, sizeof(res));
res_len = 0;
}
DEBUGP(DMM, "%s: MM %s AUTHENTICATION RESPONSE (%s = %s)\n",
vlr_subscr_name(conn->vsub),
is_umts ? "UMTS" : "GSM", is_umts ? "res" : "sres",
osmo_hexdump_nospc(res, res_len));
return vlr_subscr_rx_auth_resp(conn->vsub, classmark_is_r99(&conn->vsub->classmark),
conn->via_ran == OSMO_RAT_UTRAN_IU,
res, res_len);
}
static int gsm48_rx_mm_auth_fail(struct ran_conn *conn, struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
uint8_t cause;
uint8_t auts_tag;
uint8_t auts_len;
uint8_t *auts;
if (!conn->vsub) {
LOGP(DMM, LOGL_ERROR,
"MM R99 AUTHENTICATION FAILURE: invalid: no subscriber\n");
ran_conn_close(conn, GSM_CAUSE_AUTH_FAILED);
return -EINVAL;
}
if (msgb_l3len(msg) < sizeof(*gh) + 1) {
LOGP(DMM, LOGL_ERROR,
"%s: MM R99 AUTHENTICATION FAILURE:"
" l3 length invalid: %u\n",
vlr_subscr_name(conn->vsub), msgb_l3len(msg));
ran_conn_close(conn, GSM_CAUSE_AUTH_FAILED);
return -EINVAL;
}
cause = gh->data[0];
if (cause != GSM48_REJECT_SYNCH_FAILURE) {
LOGP(DMM, LOGL_INFO,
"%s: MM R99 AUTHENTICATION FAILURE: cause 0x%0x\n",
vlr_subscr_name(conn->vsub), cause);
vlr_subscr_rx_auth_fail(conn->vsub, NULL);
return 0;
}
/* This is a Synch Failure procedure, which should pass an AUTS to
* resynchronize the sequence nr with the HLR. Expecting exactly one
* TLV with 14 bytes of AUTS. */
if (msgb_l3len(msg) < sizeof(*gh) + 1 + 2) {
LOGP(DMM, LOGL_INFO,
"%s: MM R99 AUTHENTICATION FAILURE:"
" invalid Synch Failure: missing AUTS IE\n",
vlr_subscr_name(conn->vsub));
ran_conn_close(conn, GSM_CAUSE_AUTH_FAILED);
return -EINVAL;
}
auts_tag = gh->data[1];
auts_len = gh->data[2];
auts = &gh->data[3];
if (auts_tag != GSM48_IE_AUTS
|| auts_len != 14) {
LOGP(DMM, LOGL_INFO,
"%s: MM R99 AUTHENTICATION FAILURE:"
" invalid Synch Failure:"
" expected AUTS IE 0x%02x of 14 bytes,"
" got IE 0x%02x of %u bytes\n",
vlr_subscr_name(conn->vsub),
GSM48_IE_AUTS, auts_tag, auts_len);
ran_conn_close(conn, GSM_CAUSE_AUTH_FAILED);
return -EINVAL;
}
if (msgb_l3len(msg) < sizeof(*gh) + 1 + 2 + auts_len) {
LOGP(DMM, LOGL_INFO,
"%s: MM R99 AUTHENTICATION FAILURE:"
" invalid Synch Failure msg: message truncated (%u)\n",
vlr_subscr_name(conn->vsub), msgb_l3len(msg));
ran_conn_close(conn, GSM_CAUSE_AUTH_FAILED);
return -EINVAL;
}
/* We have an AUTS IE with exactly 14 bytes of AUTS and the msgb is
* large enough. */
DEBUGP(DMM, "%s: MM R99 AUTHENTICATION SYNCH (AUTS = %s)\n",
vlr_subscr_name(conn->vsub), osmo_hexdump_nospc(auts, 14));
return vlr_subscr_rx_auth_fail(conn->vsub, auts);
}
static int gsm48_rx_mm_tmsi_reall_compl(struct ran_conn *conn)
{
DEBUGP(DMM, "TMSI Reallocation Completed. Subscriber: %s\n",
vlr_subscr_name(conn->vsub));
if (!conn->vsub) {
LOGP(DMM, LOGL_ERROR,
"Rx MM TMSI Reallocation Complete: invalid: no subscriber\n");
return -EINVAL;
}
return vlr_subscr_rx_tmsi_reall_compl(conn->vsub);
}
/* Receive a GSM 04.08 Mobility Management (MM) message */
static int gsm0408_rcv_mm(struct ran_conn *conn, struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
int rc = 0;
switch (gsm48_hdr_msg_type(gh)) {
case GSM48_MT_MM_LOC_UPD_REQUEST:
rc = mm_rx_loc_upd_req(conn, msg);
break;
case GSM48_MT_MM_ID_RESP:
rc = mm_rx_id_resp(conn, msg);
break;
case GSM48_MT_MM_CM_SERV_REQ:
rc = gsm48_rx_mm_serv_req(conn, msg);
break;
case GSM48_MT_MM_STATUS:
rc = gsm48_rx_mm_status(msg);
break;
case GSM48_MT_MM_TMSI_REALL_COMPL:
rc = gsm48_rx_mm_tmsi_reall_compl(conn);
break;
case GSM48_MT_MM_IMSI_DETACH_IND:
rc = gsm48_rx_mm_imsi_detach_ind(conn, msg);
break;
case GSM48_MT_MM_CM_REEST_REQ:
rc = gsm48_rx_cm_reest_req(conn, msg);
break;
case GSM48_MT_MM_AUTH_RESP:
rc = gsm48_rx_mm_auth_resp(conn, msg);
break;
case GSM48_MT_MM_AUTH_FAIL:
rc = gsm48_rx_mm_auth_fail(conn, msg);
break;
default:
LOGP(DMM, LOGL_NOTICE, "Unknown GSM 04.08 MM msg type 0x%02x\n",
gh->msg_type);
break;
}
return rc;
}
/* Receive a PAGING RESPONSE message from the MS */
static int gsm48_rx_rr_pag_resp(struct ran_conn *conn, struct msgb *msg)
{
struct gsm_network *net = conn->network;
struct gsm48_hdr *gh = msgb_l3(msg);
uint8_t classmark2_len = gh->data[1];
uint8_t *classmark2 = gh->data+2;
uint8_t *mi_lv = classmark2 + classmark2_len;
struct osmo_location_area_id lai;
bool is_utran;
lai.plmn = conn->network->plmn;
lai.lac = conn->lac;
if (ran_conn_is_establishing_auth_ciph(conn)) {
LOGP(DMM, LOGL_ERROR,
"Ignoring Paging Response, conn already busy establishing authenticity\n");
return 0;
}
if (ran_conn_is_accepted(conn)) {
LOGP(DMM, LOGL_ERROR, "Ignoring Paging Response, conn already established\n");
return 0;
}
conn->complete_layer3_type = COMPLETE_LAYER3_PAGING_RESP;
ran_conn_update_id_from_mi(conn, mi_lv + 1, *mi_lv);
LOG_RAN_CONN_CAT(conn, DRR, LOGL_DEBUG, "PAGING RESPONSE\n");
is_utran = (conn->via_ran == OSMO_RAT_UTRAN_IU);
vlr_proc_acc_req(conn->fi,
RAN_CONN_E_ACCEPTED, RAN_CONN_E_CN_CLOSE, NULL,
net->vlr, conn,
VLR_PR_ARQ_T_PAGING_RESP, mi_lv, &lai,
is_utran || conn->network->authentication_required,
is_utran || conn->network->a5_encryption_mask > 0x01,
classmark2_is_r99(classmark2, classmark2_len),
is_utran);
/* From vlr_proc_acc_req() we expect an implicit dispatch of PR_ARQ_E_START we expect
* msc_vlr_subscr_assoc() to already have been called and completed. Has an error occured? */
if (!conn->vsub) {
LOG_RAN_CONN(conn, LOGL_ERROR, "subscriber not allowed to do a Paging Response\n");
return -EIO;
}
memcpy(conn->vsub->classmark.classmark2, classmark2, classmark2_len);
conn->vsub->classmark.classmark2_len = classmark2_len;
ran_conn_complete_layer_3(conn);
return 0;
}
static int gsm48_rx_rr_app_info(struct ran_conn *conn, struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
uint8_t apdu_id_flags;
uint8_t apdu_len;
uint8_t *apdu_data;
apdu_id_flags = gh->data[0];
apdu_len = gh->data[1];
apdu_data = gh->data+2;
DEBUGP(DRR, "RX APPLICATION INFO id/flags=0x%02x apdu_len=%u apdu=%s\n",
apdu_id_flags, apdu_len, osmo_hexdump(apdu_data, apdu_len));
/* we're not using the app info blob anywhere, so ignore. */
#if 0
return db_apdu_blob_store(conn->subscr, apdu_id_flags, apdu_len, apdu_data);
#else
return 0;
#endif
}
/* Receive a GSM 04.08 Radio Resource (RR) message */
static int gsm0408_rcv_rr(struct ran_conn *conn, struct msgb *msg)
{
struct gsm48_hdr *gh = msgb_l3(msg);
int rc = 0;
switch (gh->msg_type) {
case GSM48_MT_RR_PAG_RESP:
rc = gsm48_rx_rr_pag_resp(conn, msg);
break;
case GSM48_MT_RR_APP_INFO:
rc = gsm48_rx_rr_app_info(conn, msg);
break;
default:
LOGP(DRR, LOGL_NOTICE, "MSC: Unimplemented %s GSM 04.08 RR "
"message\n", gsm48_rr_msg_name(gh->msg_type));
break;
}
return rc;
}
int gsm48_send_rr_app_info(struct ran_conn *conn, uint8_t apdu_id,
uint8_t apdu_len, const uint8_t *apdu)
{
struct msgb *msg = gsm48_msgb_alloc_name("GSM 04.08 APP INF");
struct gsm48_hdr *gh;
DEBUGP(DRR, "TX APPLICATION INFO id=0x%02x, len=%u\n",
apdu_id, apdu_len);
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 2 + apdu_len);
gh->proto_discr = GSM48_PDISC_RR;
gh->msg_type = GSM48_MT_RR_APP_INFO;
gh->data[0] = apdu_id;
gh->data[1] = apdu_len;
memcpy(gh->data+2, apdu, apdu_len);
return gsm48_conn_sendmsg(msg, conn, NULL);
}
static bool msg_is_initially_permitted(const struct gsm48_hdr *hdr)
{
uint8_t pdisc = gsm48_hdr_pdisc(hdr);
uint8_t msg_type = gsm48_hdr_msg_type(hdr);
switch (pdisc) {
case GSM48_PDISC_MM:
switch (msg_type) {
case GSM48_MT_MM_LOC_UPD_REQUEST:
case GSM48_MT_MM_CM_SERV_REQ:
case GSM48_MT_MM_CM_REEST_REQ:
case GSM48_MT_MM_AUTH_RESP:
case GSM48_MT_MM_AUTH_FAIL:
case GSM48_MT_MM_ID_RESP:
case GSM48_MT_MM_TMSI_REALL_COMPL:
case GSM48_MT_MM_IMSI_DETACH_IND:
return true;
default:
break;
}
break;
case GSM48_PDISC_RR:
switch (msg_type) {
/* GSM48_MT_RR_CIPH_M_COMPL is actually handled in bssmap_rx_ciph_compl() and gets redirected in the
* BSSAP layer to ran_conn_cipher_mode_compl() (before this here is reached) */
case GSM48_MT_RR_PAG_RESP:
return true;
default:
break;
}
break;
default:
break;
}
return false;
}
void cm_service_request_concludes(struct ran_conn *conn,
struct msgb *msg)
{
/* If a CM Service Request was received before, this is the request the
* conn was opened for. No need to wait for further messages. */
if (!conn->received_cm_service_request)
return;
if (log_check_level(DMM, LOGL_DEBUG)) {
struct gsm48_hdr *gh = msgb_l3(msg);
uint8_t pdisc = gsm48_hdr_pdisc(gh);
uint8_t msg_type = gsm48_hdr_msg_type(gh);
DEBUGP(DMM, "%s: rx msg %s:"
" received_cm_service_request changes to false\n",
vlr_subscr_name(conn->vsub),
gsm48_pdisc_msgtype_name(pdisc, msg_type));
}
conn->received_cm_service_request = false;
ran_conn_put(conn, RAN_CONN_USE_CM_SERVICE);
}
/* TS 24.007 11.2.3.2.3 Message Type Octet / Duplicate Detection */
int gsm0407_pdisc_ctr_bin(uint8_t pdisc)
{
switch (pdisc) {
case GSM48_PDISC_MM:
case GSM48_PDISC_CC:
case GSM48_PDISC_NC_SS:
return 0;
case GSM48_PDISC_GROUP_CC:
return 1;
case GSM48_PDISC_BCAST_CC:
return 2;
case GSM48_PDISC_LOC:
return 3;
default:
return -1;
}
}
/* extract the N(SD) and return the modulo value for a R98 message */
static uint8_t gsm0407_determine_nsd_ret_modulo_r99(uint8_t pdisc, uint8_t msg_type, uint8_t *n_sd)
{
switch (pdisc) {
case GSM48_PDISC_MM:
case GSM48_PDISC_CC:
case GSM48_PDISC_NC_SS:
*n_sd = (msg_type >> 6) & 0x3;
return 4;
case GSM48_PDISC_GROUP_CC:
case GSM48_PDISC_BCAST_CC:
case GSM48_PDISC_LOC:
*n_sd = (msg_type >> 6) & 0x1;
return 2;
default:
/* no sequence number, we cannot detect dups */
return 0;
}
}
/* extract the N(SD) and return the modulo value for a R99 message */
static uint8_t gsm0407_determine_nsd_ret_modulo_r98(uint8_t pdisc, uint8_t msg_type, uint8_t *n_sd)
{
switch (pdisc) {
case GSM48_PDISC_MM:
case GSM48_PDISC_CC:
case GSM48_PDISC_NC_SS:
case GSM48_PDISC_GROUP_CC:
case GSM48_PDISC_BCAST_CC:
case GSM48_PDISC_LOC:
*n_sd = (msg_type >> 6) & 0x1;
return 2;
default:
/* no sequence number, we cannot detect dups */
return 0;
}
}
/* TS 24.007 11.2.3.2 Message Type Octet / Duplicate Detection */
static bool gsm0407_is_duplicate(struct ran_conn *conn, struct msgb *msg)
{
struct gsm48_hdr *gh;
uint8_t pdisc;
uint8_t n_sd, modulo;
int bin;
gh = msgb_l3(msg);
pdisc = gsm48_hdr_pdisc(gh);
if (conn->vsub && classmark_is_r99(&conn->vsub->classmark)) {
modulo = gsm0407_determine_nsd_ret_modulo_r99(pdisc, gh->msg_type, &n_sd);
} else { /* pre R99 */
modulo = gsm0407_determine_nsd_ret_modulo_r98(pdisc, gh->msg_type, &n_sd);
}
if (modulo == 0)
return false;
bin = gsm0407_pdisc_ctr_bin(pdisc);
if (bin < 0)
return false;
OSMO_ASSERT(bin < ARRAY_SIZE(conn->n_sd_next));
if (n_sd != conn->n_sd_next[bin]) {
/* not what we expected: duplicate */
return true;
} else {
/* as expected: no dup; update expected counter for next message */
conn->n_sd_next[bin] = (n_sd + 1) % modulo;
return false;
}
}
extern int gsm0408_rcv_cc(struct ran_conn *conn, struct msgb *msg);
/* Main entry point for GSM 04.08/44.008 Layer 3 data (e.g. from the BSC). */
int gsm0408_dispatch(struct ran_conn *conn, struct msgb *msg)
{
struct gsm48_hdr *gh;
uint8_t pdisc;
int rc = 0;
OSMO_ASSERT(msg->l3h);
OSMO_ASSERT(conn);
OSMO_ASSERT(msg);
gh = msgb_l3(msg);
pdisc = gsm48_hdr_pdisc(gh);
if (gsm0407_is_duplicate(conn, msg)) {
LOGP(DRLL, LOGL_NOTICE, "%s: Discarding duplicate L3 message\n",
(conn && conn->vsub) ? vlr_subscr_name(conn->vsub) : "UNKNOWN");
return 0;
}
LOGP(DRLL, LOGL_DEBUG, "Dispatching 04.08 message %s (0x%x:0x%x)\n",
gsm48_pdisc_msgtype_name(pdisc, gsm48_hdr_msg_type(gh)),
pdisc, gsm48_hdr_msg_type(gh));
if (!ran_conn_is_accepted(conn)
&& !msg_is_initially_permitted(gh)) {
LOGP(DRLL, LOGL_ERROR,
"subscr %s: Message not permitted for initial conn: %s\n",
vlr_subscr_name(conn->vsub),
gsm48_pdisc_msgtype_name(pdisc, gsm48_hdr_msg_type(gh)));
return -EACCES;
}
if (conn->vsub && conn->vsub->cs.attached_via_ran != conn->via_ran) {
LOGP(DMM, LOGL_ERROR,
"%s: Illegal situation: RAN type mismatch:"
" attached via %s, received message via %s\n",
vlr_subscr_name(conn->vsub),
osmo_rat_type_name(conn->vsub->cs.attached_via_ran),
osmo_rat_type_name(conn->via_ran));
return -EACCES;
}
#if 0
if (silent_call_reroute(conn, msg))
return silent_call_rx(conn, msg);
#endif
switch (pdisc) {
case GSM48_PDISC_CC:
rc = gsm0408_rcv_cc(conn, msg);
break;
case GSM48_PDISC_MM:
rc = gsm0408_rcv_mm(conn, msg);
break;
case GSM48_PDISC_RR:
rc = gsm0408_rcv_rr(conn, msg);
break;
case GSM48_PDISC_SMS:
rc = gsm0411_rcv_sms(conn, msg);
break;
case GSM48_PDISC_MM_GPRS:
case GSM48_PDISC_SM_GPRS:
LOGP(DRLL, LOGL_NOTICE, "Unimplemented "
"GSM 04.08 discriminator 0x%02x\n", pdisc);
rc = -ENOTSUP;
break;
case GSM48_PDISC_NC_SS:
rc = gsm0911_rcv_nc_ss(conn, msg);
break;
case GSM48_PDISC_TEST:
rc = gsm0414_rcv_test(conn, msg);
break;
default:
LOGP(DRLL, LOGL_NOTICE, "Unknown "
"GSM 04.08 discriminator 0x%02x\n", pdisc);
rc = -EINVAL;
break;
}
return rc;
}
/***********************************************************************
* VLR integration
***********************************************************************/
/* VLR asks us to send an authentication request */
static int msc_vlr_tx_auth_req(void *msc_conn_ref, struct vlr_auth_tuple *at,
bool send_autn)
{
struct ran_conn *conn = msc_conn_ref;
return gsm48_tx_mm_auth_req(conn, at->vec.rand,
send_autn? at->vec.autn : NULL,
at->key_seq);
}
/* VLR asks us to send an authentication reject */
static int msc_vlr_tx_auth_rej(void *msc_conn_ref)
{
struct ran_conn *conn = msc_conn_ref;
return gsm48_tx_mm_auth_rej(conn);
}
/* VLR asks us to transmit an Identity Request of given type */
static int msc_vlr_tx_id_req(void *msc_conn_ref, uint8_t mi_type)
{
struct ran_conn *conn = msc_conn_ref;
return mm_tx_identity_req(conn, mi_type);
}
/* VLR asks us to transmit a Location Update Accept */
static int msc_vlr_tx_lu_acc(void *msc_conn_ref, uint32_t send_tmsi)
{
struct ran_conn *conn = msc_conn_ref;
return gsm0408_loc_upd_acc(conn, send_tmsi);
}
/* VLR asks us to transmit a Location Update Reject */
static int msc_vlr_tx_lu_rej(void *msc_conn_ref, enum gsm48_reject_value cause)
{
struct ran_conn *conn = msc_conn_ref;
return gsm0408_loc_upd_rej(conn, cause);
}
/* VLR asks us to transmit a CM Service Accept */
static int msc_vlr_tx_cm_serv_acc(void *msc_conn_ref)
{
struct ran_conn *conn = msc_conn_ref;
return msc_gsm48_tx_mm_serv_ack(conn);
}
static int msc_vlr_tx_common_id(void *msc_conn_ref)
{
struct ran_conn *conn = msc_conn_ref;
return msc_tx_common_id(conn);
}
/* VLR asks us to transmit MM info. */
static int msc_vlr_tx_mm_info(void *msc_conn_ref)
{
struct ran_conn *conn = msc_conn_ref;
if (!conn->network->send_mm_info)
return 0;
return gsm48_tx_mm_info(conn);
}
/* VLR asks us to transmit a CM Service Reject */
static int msc_vlr_tx_cm_serv_rej(void *msc_conn_ref, enum gsm48_reject_value cause)
{
struct ran_conn *conn = msc_conn_ref;
int rc;
rc = msc_gsm48_tx_mm_serv_rej(conn, cause);
if (conn->received_cm_service_request) {
conn->received_cm_service_request = false;
ran_conn_put(conn, RAN_CONN_USE_CM_SERVICE);
}
return rc;
}
/* For msc_vlr_set_ciph_mode() */
osmo_static_assert(sizeof(((struct gsm0808_encrypt_info*)0)->key) >= sizeof(((struct osmo_auth_vector*)0)->kc),
gsm0808_encrypt_info_key_fits_osmo_auth_vec_kc);
int ran_conn_geran_set_cipher_mode(struct ran_conn *conn, bool umts_aka, bool retrieve_imeisv)
{
struct gsm_network *net = conn->network;
struct gsm0808_encrypt_info ei;
int i, j = 0;
int request_classmark = 0;
int request_classmark_for_a5_n = 0;
struct vlr_auth_tuple *tuple = conn->vsub->last_tuple;
if (!conn || !conn->vsub || !conn->vsub->last_tuple) {
/* This should really never happen, because we checked this in msc_vlr_set_ciph_mode()
* already. */
LOGP(DMM, LOGL_ERROR, "Internal error: missing state during Ciphering Mode Command\n");
return -EINVAL;
}
for (i = 0; i < 8; i++) {
int supported;
/* A5/n permitted by osmo-msc.cfg? */
if (!(net->a5_encryption_mask & (1 << i)))
continue;
/* A5/n supported by MS? */
supported = classmark_supports_a5(&conn->vsub->classmark, i);
if (supported == 1) {
ei.perm_algo[j++] = vlr_ciph_to_gsm0808_alg_id(i);
/* A higher A5/n is supported, so no need to request a Classmark
* for support of a lesser A5/n. */
request_classmark = 0;
} else if (supported < 0) {
request_classmark = -supported;
request_classmark_for_a5_n = i;
}
}
ei.perm_algo_len = j;
if (request_classmark) {
/* The highest A5/n as from osmo-msc.cfg might be available, but we are
* still missing the Classmark information for that from the MS. First
* ask for that. */
LOGP(DMM, LOGL_DEBUG, "%s: to determine whether A5/%d is supported,"
" first ask for a Classmark Update to obtain Classmark %d\n",
vlr_subscr_name(conn->vsub), request_classmark_for_a5_n,
request_classmark);
return ran_conn_classmark_request_then_cipher_mode_cmd(conn, umts_aka, retrieve_imeisv);
}
if (ei.perm_algo_len == 0) {
LOGP(DMM, LOGL_ERROR, "%s: cannot start ciphering, no intersection "
"between MSC-configured and MS-supported A5 algorithms\n",
vlr_subscr_name(conn->vsub));
return -ENOTSUP;
}
DEBUGP(DMM, "-> CIPHER MODE COMMAND %s\n", vlr_subscr_name(conn->vsub));
tuple = conn->vsub->last_tuple;
/* In case of UMTS AKA, the Kc for ciphering must be derived from the 3G auth
* tokens. tuple->vec.kc was calculated from the GSM algorithm and is not
* necessarily a match for the UMTS AKA tokens. */
if (umts_aka)
osmo_auth_c3(ei.key, tuple->vec.ck, tuple->vec.ik);
else
memcpy(ei.key, tuple->vec.kc, sizeof(tuple->vec.kc));
ei.key_len = sizeof(tuple->vec.kc);
conn->geran_encr = (struct geran_encr){};
if (ei.key_len <= sizeof(conn->geran_encr.key)) {
memcpy(conn->geran_encr.key, ei.key, ei.key_len);
conn->geran_encr.key_len = ei.key_len;
}
/* conn->geran_encr.alg_id remains unknown until we receive a Cipher Mode Complete from the BSC */
return a_iface_tx_cipher_mode(conn, &ei, retrieve_imeisv);
}
/* VLR asks us to start using ciphering.
* (Keep non-static to allow regression testing on this function.) */
int msc_vlr_set_ciph_mode(void *msc_conn_ref,
bool umts_aka,
bool retrieve_imeisv)
{
struct ran_conn *conn = msc_conn_ref;
struct vlr_subscr *vsub;
struct vlr_auth_tuple *tuple;
if (!conn || !conn->vsub) {
LOGP(DMM, LOGL_ERROR, "Cannot send Ciphering Mode Command to"
" NULL conn/subscriber");
return -EINVAL;
}
vsub = conn->vsub;
tuple = vsub->last_tuple;
if (!tuple) {
LOGP(DMM, LOGL_ERROR, "subscr %s: Cannot send Ciphering Mode"
" Command: no auth tuple available\n",
vlr_subscr_name(vsub));
return -EINVAL;
}
switch (conn->via_ran) {
case OSMO_RAT_GERAN_A:
return ran_conn_geran_set_cipher_mode(conn, umts_aka, retrieve_imeisv);
case OSMO_RAT_UTRAN_IU:
#ifdef BUILD_IU
DEBUGP(DMM, "-> SECURITY MODE CONTROL %s\n",
vlr_subscr_name(conn->vsub));
return ranap_iu_tx_sec_mode_cmd(conn->iu.ue_ctx, &tuple->vec, 0, 1);
#else
LOGP(DMM, LOGL_ERROR, "Cannot send Security Mode Control over OSMO_RAT_UTRAN_IU,"
" built without Iu support\n");
return -ENOTSUP;
#endif
default:
break;
}
LOGP(DMM, LOGL_ERROR,
"%s: cannot start ciphering, unknown RAN type %d\n",
vlr_subscr_name(conn->vsub), conn->via_ran);
return -ENOTSUP;
}
void ran_conn_rx_sec_mode_compl(struct ran_conn *conn)
{
struct vlr_ciph_result vlr_res = {};
if (!conn || !conn->vsub) {
LOGP(DMM, LOGL_ERROR,
"Rx Security Mode Complete for invalid conn\n");
return;
}
DEBUGP(DMM, "<- SECURITY MODE COMPLETE %s\n",
vlr_subscr_name(conn->vsub));
vlr_res.cause = VLR_CIPH_COMPL;
vlr_subscr_rx_ciph_res(conn->vsub, &vlr_res);
}
/* VLR informs us that the subscriber data has somehow been modified */
static void msc_vlr_subscr_update(struct vlr_subscr *subscr)
{
LOGVSUBP(LOGL_NOTICE, subscr, "VLR: update for IMSI=%s (MSISDN=%s, used=%d)\n",
subscr->imsi, subscr->msisdn, subscr->use_count);
ran_conn_update_id_for_vsub(subscr);
}
static void update_classmark(const struct gsm_classmark *src, struct gsm_classmark *dst)
{
if (src->classmark1_set) {
dst->classmark1 = src->classmark1;
dst->classmark1_set = true;
}
if (src->classmark2_len) {
dst->classmark2_len = src->classmark2_len;
memcpy(dst->classmark2, src->classmark2, sizeof(dst->classmark2));
}
if (src->classmark3_len) {
dst->classmark3_len = src->classmark3_len;
memcpy(dst->classmark3, src->classmark3, sizeof(dst->classmark3));
}
}
/* VLR informs us that the subscriber has been associated with a conn */
static int msc_vlr_subscr_assoc(void *msc_conn_ref,
struct vlr_subscr *vsub)
{
struct ran_conn *conn = msc_conn_ref;
OSMO_ASSERT(vsub);
if (conn->vsub) {
if (conn->vsub == vsub)
LOG_RAN_CONN(conn, LOGL_NOTICE, "msc_vlr_subscr_assoc(): conn already associated with %s\n",
vlr_subscr_name(vsub));
else {
LOG_RAN_CONN(conn, LOGL_ERROR, "msc_vlr_subscr_assoc(): conn already associated with a subscriber,"
" cannot associate with %s\n", vlr_subscr_name(vsub));
return -EINVAL;
}
}
conn->vsub = vlr_subscr_get(vsub);
OSMO_ASSERT(conn->vsub);
conn->vsub->cs.attached_via_ran = conn->via_ran;
/* In case we have already received Classmark Information before the VLR Subscriber was
* associated with the conn: merge the new Classmark into vsub->classmark. Don't overwrite valid
* vsub->classmark with unset classmark, though. */
update_classmark(&conn->temporary_classmark, &conn->vsub->classmark);
ran_conn_update_id(conn);
return 0;
}
static int msc_vlr_route_gsup_msg(struct vlr_subscr *vsub,
struct osmo_gsup_message *gsup_msg)
{
switch (gsup_msg->message_type) {
/* GSM 09.11 code implementing SS/USSD */
case OSMO_GSUP_MSGT_PROC_SS_REQUEST:
case OSMO_GSUP_MSGT_PROC_SS_RESULT:
case OSMO_GSUP_MSGT_PROC_SS_ERROR:
DEBUGP(DMSC, "Routed to GSM 09.11 SS/USSD handler\n");
return gsm0911_gsup_handler(vsub, gsup_msg);
/* GSM 04.11 code implementing MO SMS */
case OSMO_GSUP_MSGT_MO_FORWARD_SM_ERROR:
case OSMO_GSUP_MSGT_MO_FORWARD_SM_RESULT:
case OSMO_GSUP_MSGT_READY_FOR_SM_ERROR:
case OSMO_GSUP_MSGT_READY_FOR_SM_RESULT:
DEBUGP(DMSC, "Routed to GSM 04.11 MO handler\n");
return gsm411_gsup_mo_handler(vsub, gsup_msg);
/* GSM 04.11 code implementing MT SMS */
case OSMO_GSUP_MSGT_MT_FORWARD_SM_REQUEST:
DEBUGP(DMSC, "Routed to GSM 04.11 MT handler\n");
return gsm411_gsup_mt_handler(vsub, gsup_msg);
default:
LOGP(DMM, LOGL_ERROR, "No handler found for %s, dropping message...\n",
osmo_gsup_message_type_name(gsup_msg->message_type));
return -GMM_CAUSE_MSGT_NOTEXIST_NOTIMPL;
}
}
/* operations that we need to implement for libvlr */
static const struct vlr_ops msc_vlr_ops = {
.tx_auth_req = msc_vlr_tx_auth_req,
.tx_auth_rej = msc_vlr_tx_auth_rej,
.tx_id_req = msc_vlr_tx_id_req,
.tx_lu_acc = msc_vlr_tx_lu_acc,
.tx_lu_rej = msc_vlr_tx_lu_rej,
.tx_cm_serv_acc = msc_vlr_tx_cm_serv_acc,
.tx_cm_serv_rej = msc_vlr_tx_cm_serv_rej,
.set_ciph_mode = msc_vlr_set_ciph_mode,
.tx_common_id = msc_vlr_tx_common_id,
.tx_mm_info = msc_vlr_tx_mm_info,
.subscr_update = msc_vlr_subscr_update,
.subscr_assoc = msc_vlr_subscr_assoc,
.forward_gsup_msg = msc_vlr_route_gsup_msg,
};
/* Allocate net->vlr so that the VTY may configure the VLR's data structures */
int msc_vlr_alloc(struct gsm_network *net)
{
net->vlr = vlr_alloc(net, &msc_vlr_ops);
if (!net->vlr)
return -ENOMEM;
net->vlr->user_ctx = net;
return 0;
}
/* Launch the VLR, i.e. its GSUP connection */
int msc_vlr_start(struct gsm_network *net)
{
struct ipaccess_unit *ipa_dev;
OSMO_ASSERT(net->vlr);
ipa_dev = talloc_zero(net->vlr, struct ipaccess_unit);
ipa_dev->unit_name = "MSC";
ipa_dev->serno = net->msc_ipa_name; /* NULL unless configured via VTY */
ipa_dev->swversion = PACKAGE_NAME "-" PACKAGE_VERSION;
return vlr_start(ipa_dev, net->vlr, net->gsup_server_addr_str, net->gsup_server_port);
}
struct msgb *gsm48_create_mm_serv_rej(enum gsm48_reject_value value)
{
struct msgb *msg;
struct gsm48_hdr *gh;
msg = gsm48_msgb_alloc_name("GSM 04.08 SERV REJ");
if (!msg)
return NULL;
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
gh->proto_discr = GSM48_PDISC_MM;
gh->msg_type = GSM48_MT_MM_CM_SERV_REJ;
gh->data[0] = value;
return msg;
}
struct msgb *gsm48_create_loc_upd_rej(uint8_t cause)
{
struct gsm48_hdr *gh;
struct msgb *msg;
msg = gsm48_msgb_alloc_name("GSM 04.08 LOC UPD REJ");
if (!msg)
return NULL;
gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
gh->proto_discr = GSM48_PDISC_MM;
gh->msg_type = GSM48_MT_MM_LOC_UPD_REJECT;
gh->data[0] = cause;
return msg;
}
int gsm48_extract_mi(uint8_t *classmark2_lv, int length, char *mi_string, uint8_t *mi_type)
{
/* Check the size for the classmark */
if (length < 1 + *classmark2_lv)
return -1;
uint8_t *mi_lv = classmark2_lv + *classmark2_lv + 1;
if (length < 2 + *classmark2_lv + mi_lv[0])
return -2;
*mi_type = mi_lv[1] & GSM_MI_TYPE_MASK;
return gsm48_mi_to_string(mi_string, GSM48_MI_SIZE, mi_lv+1, *mi_lv);
}
int gsm48_paging_extract_mi(struct gsm48_pag_resp *resp, int length,
char *mi_string, uint8_t *mi_type)
{
static const uint32_t classmark_offset =
offsetof(struct gsm48_pag_resp, classmark2);
uint8_t *classmark2_lv = (uint8_t *) &resp->classmark2;
return gsm48_extract_mi(classmark2_lv, length - classmark_offset,
mi_string, mi_type);
}
View Git Blame Copy Permalink