1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
|
#include <stdint.h>
#include <errno.h>
#include <stdio.h>
#include <osmocore/msgb.h>
#include <osmocore/rsl.h>
#include <osmocore/tlv.h>
#include <osmocore/gsm48_ie.h>
#include <osmocore/protocol/gsm_04_08.h>
#include <osmocom/bb/common/logging.h>
#include <osmocom/bb/common/lapdm.h>
#include <osmocom/bb/misc/rslms.h>
#include <osmocom/bb/misc/layer3.h>
#include <osmocom/bb/common/osmocom_data.h>
#include <osmocom/bb/common/l1ctl.h>
static struct {
int has_si1;
int ccch_mode;
int ccch_enabled;
int rach_count;
struct gsm_sysinfo_freq cell_arfcns[1024];
} app_state;
static void dump_bcch(struct osmocom_ms *ms, uint8_t tc, const uint8_t *data)
{
struct gsm48_system_information_type_header *si_hdr;
si_hdr = (struct gsm48_system_information_type_header *) data;
/* GSM 05.02 §6.3.1.3 Mapping of BCCH data */
switch (si_hdr->system_information) {
case GSM48_MT_RR_SYSINFO_1:
fprintf(stderr, "\tSI1");
#ifdef BCCH_TC_CHECK
if (tc != 0)
fprintf(stderr, " on wrong TC");
#endif
if (!app_state.has_si1) {
struct gsm48_system_information_type_1 *si1 =
(struct gsm48_system_information_type_1 *)data;
gsm48_decode_freq_list(&app_state.cell_arfcns,
si1->cell_channel_description,
sizeof(si1->cell_channel_description),
0xff, 0x01);
app_state.has_si1 = 1;
}
break;
case GSM48_MT_RR_SYSINFO_2:
fprintf(stderr, "\tSI2");
#ifdef BCCH_TC_CHECK
if (tc != 1)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_3:
fprintf(stderr, "\tSI3");
#ifdef BCCH_TC_CHECK
if (tc != 2 && tc != 6)
fprintf(stderr, " on wrong TC");
#endif
if (app_state.ccch_mode == CCCH_MODE_NONE) {
struct gsm48_system_information_type_3 *si3 =
(struct gsm48_system_information_type_3 *)data;
if (si3->control_channel_desc.ccch_conf == RSL_BCCH_CCCH_CONF_1_C)
app_state.ccch_mode = CCCH_MODE_COMBINED;
else
app_state.ccch_mode = CCCH_MODE_NON_COMBINED;
l1ctl_tx_ccch_mode_req(ms, app_state.ccch_mode);
}
break;
case GSM48_MT_RR_SYSINFO_4:
fprintf(stderr, "\tSI4");
#ifdef BCCH_TC_CHECK
if (tc != 3 && tc != 7)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_5:
fprintf(stderr, "\tSI5");
break;
case GSM48_MT_RR_SYSINFO_6:
fprintf(stderr, "\tSI6");
break;
case GSM48_MT_RR_SYSINFO_7:
fprintf(stderr, "\tSI7");
#ifdef BCCH_TC_CHECK
if (tc != 7)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_8:
fprintf(stderr, "\tSI8");
#ifdef BCCH_TC_CHECK
if (tc != 3)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_9:
fprintf(stderr, "\tSI9");
#ifdef BCCH_TC_CHECK
if (tc != 4)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_13:
fprintf(stderr, "\tSI13");
#ifdef BCCH_TC_CHECK
if (tc != 4 && tc != 0)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_16:
fprintf(stderr, "\tSI16");
#ifdef BCCH_TC_CHECK
if (tc != 6)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_17:
fprintf(stderr, "\tSI17");
#ifdef BCCH_TC_CHECK
if (tc != 2)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_2bis:
fprintf(stderr, "\tSI2bis");
#ifdef BCCH_TC_CHECK
if (tc != 5)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_2ter:
fprintf(stderr, "\tSI2ter");
#ifdef BCCH_TC_CHECK
if (tc != 5 && tc != 4)
fprintf(stderr, " on wrong TC");
#endif
break;
case GSM48_MT_RR_SYSINFO_5bis:
fprintf(stderr, "\tSI5bis");
break;
case GSM48_MT_RR_SYSINFO_5ter:
fprintf(stderr, "\tSI5ter");
break;
default:
fprintf(stderr, "\tUnknown SI");
break;
};
fprintf(stderr, "\n");
}
/* send location updating request * (as part of RSLms EST IND /
LAPDm SABME) */
static int gsm48_tx_loc_upd_req(struct osmocom_ms *ms, uint8_t chan_nr)
{
struct msgb *msg = msgb_alloc_headroom(256, 16, "loc_upd_req");
struct gsm48_hdr *gh;
struct gsm48_loc_upd_req *lu_r;
DEBUGP(DMM, "chan_nr=%u\n", chan_nr);
msg->l3h = msgb_put(msg, sizeof(*gh));
gh = (struct gsm48_hdr *) msg->l3h;
gh->proto_discr = GSM48_PDISC_MM;
gh->msg_type = GSM48_MT_MM_LOC_UPD_REQUEST;
lu_r = (struct gsm48_loc_upd_req *) msgb_put(msg, sizeof(*lu_r));
lu_r->type = GSM48_LUPD_IMSI_ATT;
lu_r->key_seq = 0;
/* FIXME: set LAI and CM1 */
/* FIXME: set MI */
lu_r->mi_len = 0;
return rslms_tx_rll_req_l3(ms, RSL_MT_EST_REQ, chan_nr, 0, msg);
}
static int gsm48_rx_imm_ass(struct msgb *msg, struct osmocom_ms *ms)
{
struct gsm48_imm_ass *ia = msgb_l3(msg);
uint8_t ch_type, ch_subch, ch_ts;
int rv;
/* Discard packet TBF assignement */
if (ia->page_mode & 0xf0)
return 0;
/* FIXME: compare RA and GSM time with when we sent RACH req */
rsl_dec_chan_nr(ia->chan_desc.chan_nr, &ch_type, &ch_subch, &ch_ts);
if (!ia->chan_desc.h0.h) {
/* Non-hopping */
uint16_t arfcn;
arfcn = ia->chan_desc.h0.arfcn_low | (ia->chan_desc.h0.arfcn_high << 8);
DEBUGP(DRR, "GSM48 IMM ASS (ra=0x%02x, chan_nr=0x%02x, "
"ARFCN=%u, TS=%u, SS=%u, TSC=%u) ", ia->req_ref.ra,
ia->chan_desc.chan_nr, arfcn, ch_ts, ch_subch,
ia->chan_desc.h0.tsc);
/* request L1 to go to dedicated mode on assigned channel */
rv = l1ctl_tx_dm_est_req_h0(ms,
arfcn, ia->chan_desc.chan_nr, ia->chan_desc.h0.tsc,
GSM48_CMODE_SIGN);
} else {
/* Hopping */
uint8_t maio, hsn, ma_len;
uint16_t ma[64], arfcn;
int i, j, k;
hsn = ia->chan_desc.h1.hsn;
maio = ia->chan_desc.h1.maio_low | (ia->chan_desc.h1.maio_high << 2);
DEBUGP(DRR, "GSM48 IMM ASS (ra=0x%02x, chan_nr=0x%02x, "
"HSN=%u, MAIO=%u, TS=%u, SS=%u, TSC=%u) ", ia->req_ref.ra,
ia->chan_desc.chan_nr, hsn, maio, ch_ts, ch_subch,
ia->chan_desc.h1.tsc);
/* decode mobile allocation */
ma_len = 0;
for (i=1, j=0; i<=1024; i++) {
arfcn = i & 1023;
if (app_state.cell_arfcns[arfcn].mask & 0x01) {
k = ia->mob_alloc_len - (j>>3) - 1;
if (ia->mob_alloc[k] & (1 << (j&7))) {
ma[ma_len++] = arfcn;
}
j++;
}
}
/* request L1 to go to dedicated mode on assigned channel */
rv = l1ctl_tx_dm_est_req_h1(ms,
maio, hsn, ma, ma_len,
ia->chan_desc.chan_nr, ia->chan_desc.h1.tsc,
GSM48_CMODE_SIGN);
}
DEBUGPC(DRR, "\n");
rv = gsm48_tx_loc_upd_req(ms, ia->chan_desc.chan_nr);
return rv;
}
int gsm48_rx_ccch(struct msgb *msg, struct osmocom_ms *ms)
{
struct gsm48_system_information_type_header *sih = msgb_l3(msg);
int rc = 0;
if (sih->rr_protocol_discriminator != GSM48_PDISC_RR)
LOGP(DRR, LOGL_ERROR, "PCH pdisc != RR\n");
switch (sih->system_information) {
case GSM48_MT_RR_PAG_REQ_1:
case GSM48_MT_RR_PAG_REQ_2:
case GSM48_MT_RR_PAG_REQ_3:
/* FIXME: implement decoding of paging request */
break;
case GSM48_MT_RR_IMM_ASS:
rc = gsm48_rx_imm_ass(msg, ms);
break;
default:
LOGP(DRR, LOGL_NOTICE, "unknown PCH/AGCH type 0x%02x\n",
sih->system_information);
rc = -EINVAL;
}
return rc;
}
int gsm48_rx_bcch(struct msgb *msg, struct osmocom_ms *ms)
{
/* FIXME: we have lost the gsm frame time until here, need to store it
* in some msgb context */
//dump_bcch(dl->time.tc, ccch->data);
dump_bcch(ms, 0, msg->l3h);
/* Req channel logic */
if (app_state.ccch_enabled && (app_state.rach_count < 2)) {
l1ctl_tx_rach_req(ms, app_state.rach_count, 0,
app_state.ccch_mode == CCCH_MODE_COMBINED);
app_state.rach_count++;
}
return 0;
}
void layer3_app_reset(void)
{
/* Reset state */
app_state.has_si1 = 0;
app_state.ccch_mode = CCCH_MODE_NONE;
app_state.ccch_enabled = 0;
app_state.rach_count = 0;
memset(&app_state.cell_arfcns, 0x00, sizeof(app_state.cell_arfcns));
}
|
