store classmark in vlr_subscr, not conn

Store all Classmark information in the VLR.

So, we now always know the Classmark 1 (mandatory IE for LU). This is visible
in the msc_vlr_tests -- they no longer indicate "assuming A5/1 is supported"
because classmark 1 is missing, because we now know the Classmark 1.

Rationale:

During Location Updating, we receive Classmark 1; during CM Service Request and
Paging Response, we receive Classmark 2. So far we stored these only for the
duration of the conn, so as soon as a LU is complete, we would forget CM1.

In other words, for anything else than a LU Request, we had no Classmark 1
available at all.

During Ciphering Mode Command, we rely on Classmark 1 to determine whether A5/1
is supported. That is moot if we don't even have a Classmark 1 for any CM
Service Request or Paging Response initiated connections.

The only reason that A5/1 worked is that we assume A5/1 to work if Classmark 1
is missing. To add to the confusion, if a phone indicated that it did *not*
support A5/1 in the Classmark 1, according to spec we're supposed to not
service it at all. A code comment however says that we instead want to heed the
flag -- which so far was only present in a Location Updating initiated
connection. Now we can make this decision without assuming things.

This got my attention while hacking on sending a BSSMAP Classmark Request from
the MSC if it finds missing Classmark information, and was surprised to see it
it lacking CM1 to decide about A5/1.

Change-Id: I27081bf6e9e017923b2d02607f7ea06beddad82a
changes/85/10985/1
Neels Hofmeyr 4 years ago
parent 5e91debe4e
commit 986fe7ed18
  1. 2
      include/osmocom/msc/gsm_data.h
  2. 2
      include/osmocom/msc/vlr.h
  3. 109
      src/libmsc/gsm_04_08.c
  4. 22
      src/libmsc/osmo_msc.c
  5. 6
      tests/msc_vlr/msc_vlr_test_gsm_ciph.err
  6. 3
      tests/msc_vlr/msc_vlr_test_rest.err

@ -127,8 +127,6 @@ struct gsm_subscriber_connection {
/* connected via 2G or 3G? */
enum ran_type via_ran;
struct gsm_classmark classmark;
uint16_t lac;
struct gsm_encr encr;

@ -174,6 +174,8 @@ struct vlr_subscr {
uint8_t lac;
enum ran_type attached_via_ran;
} cs;
struct gsm_classmark classmark;
};
enum vlr_ciph {

@ -98,14 +98,25 @@ int gsm48_tx_simple(struct gsm_subscriber_connection *conn,
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)
{
int rev_lev = 0;
if (cm->classmark1_set)
rev_lev = cm->classmark1.rev_lev;
else if (cm->classmark2_len > 0)
rev_lev = (cm->classmark2[0] >> 5) & 0x3;
return rev_lev >= 2;
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 */
@ -345,9 +356,6 @@ int mm_rx_loc_upd_req(struct gsm_subscriber_connection *conn, struct msgb *msg)
msc_subscr_conn_update_id(conn, COMPLETE_LAYER3_LU, mi_string);
conn->classmark.classmark1 = lu->classmark1;
conn->classmark.classmark1_set = true;
DEBUGP(DMM, "LOCATION UPDATING REQUEST: MI(%s)=%s type=%s\n",
gsm48_mi_type_name(mi_type), mi_string,
get_value_string(lupd_names, lu->type));
@ -402,7 +410,7 @@ int mm_rx_loc_upd_req(struct gsm_subscriber_connection *conn, struct msgb *msg)
&old_lai, &new_lai,
is_utran || conn->network->authentication_required,
is_utran || conn->network->a5_encryption_mask > 0x01,
classmark_is_r99(&conn->classmark),
classmark1_is_r99(&lu->classmark1),
is_utran,
net->vlr->cfg.assign_tmsi);
if (!lu_fsm) {
@ -421,6 +429,9 @@ int mm_rx_loc_upd_req(struct gsm_subscriber_connection *conn, struct msgb *msg)
return -EIO;
}
conn->vsub->classmark.classmark1 = lu->classmark1;
conn->vsub->classmark.classmark1_set = true;
msc_subscr_conn_complete_layer_3(conn);
return 0;
}
@ -773,8 +784,6 @@ int gsm48_rx_mm_serv_req(struct gsm_subscriber_connection *conn, struct msgb *ms
msc_subscr_conn_update_id(conn, COMPLETE_LAYER3_CM_SERVICE_REQ, mi_string);
osmo_signal_dispatch(SS_SUBSCR, S_SUBSCR_IDENTITY, mi_p);
memcpy(conn->classmark.classmark2, classmark2, classmark2_len);
conn->classmark.classmark2_len = classmark2_len;
is_utran = (conn->via_ran == RAN_UTRAN_IU);
vlr_proc_acc_req(conn->fi,
@ -783,9 +792,20 @@ int gsm48_rx_mm_serv_req(struct gsm_subscriber_connection *conn, struct msgb *ms
VLR_PR_ARQ_T_CM_SERV_REQ, mi-1, &lai,
is_utran || conn->network->authentication_required,
is_utran || conn->network->a5_encryption_mask > 0x01,
classmark_is_r99(&conn->classmark),
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) {
LOGP(DRR, LOGL_ERROR, "%s: subscriber not allowed to do a CM Service Request\n",
mi_string);
return -EIO;
}
memcpy(conn->vsub->classmark.classmark2, classmark2, classmark2_len);
conn->vsub->classmark.classmark2_len = classmark2_len;
msc_subscr_conn_complete_layer_3(conn);
return 0;
}
@ -846,11 +866,6 @@ static int gsm48_rx_mm_imsi_detach_ind(struct gsm_subscriber_connection *conn, s
break;
}
/* TODO? We used to remember the subscriber's classmark1 here and
* stored it in the old sqlite db, but now we store it in a conn that
* will be discarded anyway: */
conn->classmark.classmark1 = idi->classmark1;
if (!vsub) {
LOGP(DMM, LOGL_ERROR, "IMSI DETACH for unknown subscriber MI(%s)=%s\n",
gsm48_mi_type_name(mi_type), mi_string);
@ -860,6 +875,9 @@ static int gsm48_rx_mm_imsi_detach_ind(struct gsm_subscriber_connection *conn, s
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);
@ -986,7 +1004,7 @@ static int gsm48_rx_mm_auth_resp(struct gsm_subscriber_connection *conn, struct
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->classmark),
return vlr_subscr_rx_auth_resp(conn->vsub, classmark_is_r99(&conn->vsub->classmark),
conn->via_ran == RAN_UTRAN_IU,
res, res_len);
}
@ -1128,27 +1146,15 @@ static int gsm0408_rcv_mm(struct gsm_subscriber_connection *conn, struct msgb *m
return rc;
}
static uint8_t *gsm48_cm2_get_mi(uint8_t *classmark2_lv, unsigned int tot_len)
{
/* Check the size for the classmark */
if (tot_len < 1 + *classmark2_lv)
return NULL;
uint8_t *mi_lv = classmark2_lv + *classmark2_lv + 1;
if (tot_len < 2 + *classmark2_lv + mi_lv[0])
return NULL;
return mi_lv;
}
/* Receive a PAGING RESPONSE message from the MS */
static int gsm48_rx_rr_pag_resp(struct gsm_subscriber_connection *conn, struct msgb *msg)
{
struct gsm_network *net = conn->network;
struct gsm48_hdr *gh = msgb_l3(msg);
struct gsm48_pag_resp *resp;
uint8_t *classmark2_lv = gh->data + 1;
uint8_t *mi_lv;
uint8_t classmark2_len = gh->data[1];
uint8_t *classmark2 = gh->data+2;
uint8_t *mi_lv = classmark2 + classmark2_len;
uint8_t mi_type;
char mi_string[GSM48_MI_SIZE];
struct osmo_location_area_id lai;
@ -1158,8 +1164,11 @@ static int gsm48_rx_rr_pag_resp(struct gsm_subscriber_connection *conn, struct m
lai.lac = conn->lac;
resp = (struct gsm48_pag_resp *) &gh->data[0];
gsm48_paging_extract_mi(resp, msgb_l3len(msg) - sizeof(*gh),
mi_string, &mi_type);
if (gsm48_paging_extract_mi(resp, msgb_l3len(msg) - sizeof(*gh), mi_string, &mi_type) <= 0) {
LOGP(DRR, LOGL_ERROR, "PAGING RESPONSE: invalid Mobile Identity\n");
return -EINVAL;
}
if (msc_subscr_conn_is_establishing_auth_ciph(conn)) {
LOGP(DMM, LOGL_ERROR,
@ -1174,17 +1183,8 @@ static int gsm48_rx_rr_pag_resp(struct gsm_subscriber_connection *conn, struct m
DEBUGP(DRR, "PAGING RESPONSE: MI(%s)=%s\n", gsm48_mi_type_name(mi_type), mi_string);
mi_lv = gsm48_cm2_get_mi(classmark2_lv, msgb_l3len(msg) - sizeof(*gh));
if (!mi_lv) {
LOGP(DRR, LOGL_ERROR, "PAGING RESPONSE: invalid Mobile Identity\n");
return -1;
}
msc_subscr_conn_update_id(conn, COMPLETE_LAYER3_PAGING_RESP, mi_string);
memcpy(conn->classmark.classmark2, classmark2_lv+1, *classmark2_lv);
conn->classmark.classmark2_len = *classmark2_lv;
is_utran = (conn->via_ran == RAN_UTRAN_IU);
vlr_proc_acc_req(conn->fi,
SUBSCR_CONN_E_ACCEPTED, SUBSCR_CONN_E_CN_CLOSE, NULL,
@ -1192,9 +1192,20 @@ static int gsm48_rx_rr_pag_resp(struct gsm_subscriber_connection *conn, struct m
VLR_PR_ARQ_T_PAGING_RESP, mi_lv, &lai,
is_utran || conn->network->authentication_required,
is_utran || conn->network->a5_encryption_mask > 0x01,
classmark_is_r99(&conn->classmark),
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) {
LOGP(DRR, LOGL_ERROR, "%s: subscriber not allowed to do a Paging Response\n",
mi_string);
return -EIO;
}
memcpy(conn->vsub->classmark.classmark2, classmark2, classmark2_len);
conn->vsub->classmark.classmark2_len = classmark2_len;
msc_subscr_conn_complete_layer_3(conn);
return 0;
}
@ -1390,10 +1401,10 @@ static bool gsm0407_is_duplicate(struct gsm_subscriber_connection *conn, struct
gh = msgb_l3(msg);
pdisc = gsm48_hdr_pdisc(gh);
if (conn->classmark.classmark1_set && conn->classmark.classmark1.rev_lev < 2) {
modulo = gsm0407_determine_nsd_ret_modulo_r98(pdisc, gh->msg_type, &n_sd);
} else { /* R99 */
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;
@ -1618,7 +1629,7 @@ int msc_vlr_set_ciph_mode(void *msc_conn_ref,
for (i = 0; i < 8; i++) {
if (net->a5_encryption_mask & (1 << i) &&
classmark_supports_a5(&conn->classmark, i))
classmark_supports_a5(&conn->vsub->classmark, i))
ei.perm_algo[j++] = vlr_ciph_to_gsm0808_alg_id(i);
}
ei.perm_algo_len = j;

@ -147,23 +147,25 @@ void msc_classmark_chg(struct gsm_subscriber_connection *conn,
const uint8_t *cm2, uint8_t cm2_len,
const uint8_t *cm3, uint8_t cm3_len)
{
struct gsm_classmark *cm = &conn->vsub->classmark;
if (cm2 && cm2_len) {
if (cm2_len > sizeof(conn->classmark.classmark2)) {
if (cm2_len > sizeof(cm->classmark2)) {
LOGP(DRR, LOGL_NOTICE, "%s: classmark2 is %u bytes, truncating at %zu bytes\n",
vlr_subscr_name(conn->vsub), cm2_len, sizeof(conn->classmark.classmark2));
cm2_len = sizeof(conn->classmark.classmark2);
vlr_subscr_name(conn->vsub), cm2_len, sizeof(cm->classmark2));
cm2_len = sizeof(cm->classmark2);
}
conn->classmark.classmark2_len = cm2_len;
memcpy(conn->classmark.classmark2, cm2, cm2_len);
cm->classmark2_len = cm2_len;
memcpy(cm->classmark2, cm2, cm2_len);
}
if (cm3 && cm3_len) {
if (cm3_len > sizeof(conn->classmark.classmark3)) {
if (cm3_len > sizeof(cm->classmark3)) {
LOGP(DRR, LOGL_NOTICE, "%s: classmark3 is %u bytes, truncating at %zu bytes\n",
vlr_subscr_name(conn->vsub), cm3_len, sizeof(conn->classmark.classmark3));
cm3_len = sizeof(conn->classmark.classmark3);
vlr_subscr_name(conn->vsub), cm3_len, sizeof(cm->classmark3));
cm3_len = sizeof(cm->classmark3);
}
conn->classmark.classmark3_len = cm3_len;
memcpy(conn->classmark.classmark3, cm3, cm3_len);
cm->classmark3_len = cm3_len;
memcpy(cm->classmark3, cm3, cm3_len);
}
}

@ -237,7 +237,6 @@ DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:901700000004620){PR_ARQ_S_WAIT_AU
DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:901700000004620){PR_ARQ_S_WAIT_AUTH}: _proc_arq_vlr_node2()
DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:901700000004620){PR_ARQ_S_WAIT_AUTH}: Set Ciphering Mode
DMM -> CIPHER MODE COMMAND MSISDN:46071
DMSC CLASSMARK 1 unknown, assuming MS supports A5/1
- sending Ciphering Mode Command for MSISDN:46071: include_imeisv=0
- ...perm algo: 2
- ...key: 07fa7502e07e1c00
@ -376,7 +375,6 @@ DVLR Process_Access_Request_VLR(PAGING_RESP:901700000004620){PR_ARQ_S_WAIT_AUTH}
DVLR Process_Access_Request_VLR(PAGING_RESP:901700000004620){PR_ARQ_S_WAIT_AUTH}: _proc_arq_vlr_node2()
DVLR Process_Access_Request_VLR(PAGING_RESP:901700000004620){PR_ARQ_S_WAIT_AUTH}: Set Ciphering Mode
DMM -> CIPHER MODE COMMAND MSISDN:46071
DMSC CLASSMARK 1 unknown, assuming MS supports A5/1
- sending Ciphering Mode Command for MSISDN:46071: include_imeisv=0
- ...perm algo: 2
- ...key: e2b234f807886400
@ -779,7 +777,6 @@ DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:50462976){PR_ARQ_S_WAIT_AUTH}: Re
DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:50462976){PR_ARQ_S_WAIT_AUTH}: _proc_arq_vlr_node2()
DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:50462976){PR_ARQ_S_WAIT_AUTH}: Set Ciphering Mode
DMM -> CIPHER MODE COMMAND MSISDN:46071
DMSC CLASSMARK 1 unknown, assuming MS supports A5/1
- sending Ciphering Mode Command for MSISDN:46071: include_imeisv=0
- ...perm algo: 2
- ...key: 07fa7502e07e1c00
@ -918,7 +915,6 @@ DVLR Process_Access_Request_VLR(PAGING_RESP:50462976){PR_ARQ_S_WAIT_AUTH}: Recei
DVLR Process_Access_Request_VLR(PAGING_RESP:50462976){PR_ARQ_S_WAIT_AUTH}: _proc_arq_vlr_node2()
DVLR Process_Access_Request_VLR(PAGING_RESP:50462976){PR_ARQ_S_WAIT_AUTH}: Set Ciphering Mode
DMM -> CIPHER MODE COMMAND MSISDN:46071
DMSC CLASSMARK 1 unknown, assuming MS supports A5/1
- sending Ciphering Mode Command for MSISDN:46071: include_imeisv=0
- ...perm algo: 2
- ...key: e2b234f807886400
@ -2018,7 +2014,6 @@ DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:901700000010650){PR_ARQ_S_WAIT_AU
DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:901700000010650){PR_ARQ_S_WAIT_AUTH}: _proc_arq_vlr_node2()
DVLR Process_Access_Request_VLR(CM_SERVICE_REQ:901700000010650){PR_ARQ_S_WAIT_AUTH}: Set Ciphering Mode
DMM -> CIPHER MODE COMMAND MSISDN:42342
DMSC CLASSMARK 1 unknown, assuming MS supports A5/1
- sending Ciphering Mode Command for MSISDN:42342: include_imeisv=0
- ...perm algo: 2
- ...key: da149b11d473f400
@ -2147,7 +2142,6 @@ DVLR Process_Access_Request_VLR(PAGING_RESP:901700000010650){PR_ARQ_S_WAIT_AUTH}
DVLR Process_Access_Request_VLR(PAGING_RESP:901700000010650){PR_ARQ_S_WAIT_AUTH}: _proc_arq_vlr_node2()
DVLR Process_Access_Request_VLR(PAGING_RESP:901700000010650){PR_ARQ_S_WAIT_AUTH}: Set Ciphering Mode
DMM -> CIPHER MODE COMMAND MSISDN:42342
DMSC CLASSMARK 1 unknown, assuming MS supports A5/1
- sending Ciphering Mode Command for MSISDN:42342: include_imeisv=0
- ...perm algo: 2
- ...key: 26ec67fad3073000

@ -71,8 +71,7 @@ DMM Subscr_Conn(CM_SERVICE_REQ:901700000004620){SUBSCR_CONN_S_NEW}: Received Eve
DMM Subscr_Conn(CM_SERVICE_REQ:901700000004620){SUBSCR_CONN_S_NEW}: state_chg to SUBSCR_CONN_S_RELEASING
DREF unknown: MSC conn use + release == 2 (0x101: compl_l3,release)
- BSSAP Clear --RAN_GERAN_A--> MS
DMM Subscr_Conn(CM_SERVICE_REQ:901700000004620){SUBSCR_CONN_S_RELEASING}: Received Event SUBSCR_CONN_E_COMPLETE_LAYER_3
DMM Subscr_Conn(CM_SERVICE_REQ:901700000004620){SUBSCR_CONN_S_RELEASING}: Event SUBSCR_CONN_E_COMPLETE_LAYER_3 not permitted
DRR 901700000004620: subscriber not allowed to do a CM Service Request
DREF unknown: MSC conn use - compl_l3 == 1 (0x100: release)
bssap_clear_sent == 1
- conn was released

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