Replace template-based SYSTEM INFORMATION with real implementation

Before this commit, OpenBSC used templates for the SYSTEM INFO
1, 2, 3, 4, 5 and 6 messages.  Those templates were patched in
various places to reflect the network config like ARFCN.

Now, we actually generate those SI messages ourselves, using
values from the configuration file, and even calculating neighbor
cell lists.

All bts'es that you have configured in OpenBSC will end up in
the neighbor cell list - which should be more than sufficient for
the current small-single-site networks.

5 files changed, 214 insertions, 7 deletions

diff --git a/openbsc/include/openbsc/bitvec.h b/openbsc/include/openbsc/bitvec.h
new file mode 100644
index 000000000..80ed4ad0a
--- /dev/null
+++ b/openbsc/include/openbsc/bitvec.h
@@ -0,0 +1,59 @@
+#ifndef _BITVEC_H
+#define _BITVEC_H
+
+/* bit vector utility routines */
+
+/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+
+/* In GSM mac blocks, every bit can be 0 or 1, or L or H.  L/H are
+ * defined relative to the 0x2b padding pattern */
+enum bit_value {
+	ZERO	= 0,
+	ONE	= 1,
+	L	= 2,
+	H	= 3,
+};
+
+struct bitvec {
+	unsigned int cur_bit;	/* curser to the next unused bit */
+	unsigned int data_len;	/* length of data array in bytes */
+	u_int8_t *data;		/* pointer to data array */
+};
+
+/* Set a bit at given position */
+int bitvec_set_bit_pos(struct bitvec *bv, unsigned int bitnum,
+			enum bit_value bit);
+
+/* Set the next bit in the vector */
+int bitvec_set_bit(struct bitvec *bv, enum bit_value bit);
+
+/* Set multiple bits at the current position */
+int bitvec_set_bits(struct bitvec *bv, enum bit_value *bits, int count);
+
+/* Add an unsigned integer (of length count bits) to current position */
+int bitvec_set_uint(struct bitvec *bv, unsigned int in, int count);
+
+
+/* Pad the bit vector up to a certain bit position */
+int bitvec_spare_padding(struct bitvec *bv, unsigned int up_to_bit);
+
+#endif /* _BITVEC_H */
diff --git a/openbsc/include/openbsc/gsm_04_08.h b/openbsc/include/openbsc/gsm_04_08.h
index 4a5cebf46..a3b77a8ab 100644
--- a/openbsc/include/openbsc/gsm_04_08.h
+++ b/openbsc/include/openbsc/gsm_04_08.h
@@ -187,6 +187,13 @@ struct gsm48_control_channel_descr {
 	u_int8_t t3212;
 } __attribute__ ((packed));
 
+struct gsm48_cell_options {
+	u_int8_t radio_link_timeout:4,
+		 dtx:2,
+		 pwrc:1,
+		 spare:1;
+} __attribute__ ((packed));
+
 /* Section 9.2.9 CM service request */
 struct gsm48_service_request {
 	u_int8_t cm_service_type : 4,
@@ -203,7 +210,7 @@ struct gsm48_system_information_type_1 {
 	struct gsm48_system_information_type_header header;
 	u_int8_t cell_channel_description[16];
 	struct gsm48_rach_control rach_control;
-	u_int8_t s1_reset;
+	u_int8_t rest_octets[0]; /* NCH position on the CCCH */
 } __attribute__ ((packed));
 
 /* Section 9.1.32 System information Type 2 */
@@ -220,10 +227,10 @@ struct gsm48_system_information_type_3 {
 	u_int16_t cell_identity;
 	struct gsm48_loc_area_id lai;
 	struct gsm48_control_channel_descr control_channel_desc;
-	u_int8_t cell_options;
+	struct gsm48_cell_options cell_options;
 	struct gsm48_cell_sel_par cell_sel_par;
 	struct gsm48_rach_control rach_control;
-	u_int8_t s3_reset_octets[4];
+	u_int8_t rest_octets[0];
 } __attribute__ ((packed));
 
 /* Section 9.1.36 System information Type 4 */
@@ -253,9 +260,15 @@ struct gsm48_system_information_type_6 {
 	u_int8_t system_information;
 	u_int16_t cell_identity;
 	struct gsm48_loc_area_id lai;
-	u_int8_t cell_options;
+	struct gsm48_cell_options cell_options;
 	u_int8_t ncc_permitted;
-	u_int8_t si_6_reset[0];
+	u_int8_t rest_octets[0];
+} __attribute__ ((packed));
+
+/* Section 9.1.43a System Information type 13 */
+struct gsm48_system_information_type_13 {
+	struct gsm48_system_information_type_header header;
+	u_int8_t rest_octets[0];
 } __attribute__ ((packed));
 
 /* Section 9.2.12 IMSI Detach Indication */
diff --git a/openbsc/include/openbsc/gsm_data.h b/openbsc/include/openbsc/gsm_data.h
index b4a8ef550..fcd623fe6 100644
--- a/openbsc/include/openbsc/gsm_data.h
+++ b/openbsc/include/openbsc/gsm_data.h
@@ -356,8 +356,6 @@ struct gsm_bts {
 	/* number of this BTS on given E1 link */
 	u_int8_t bts_nr;
 
-	struct gsm48_control_channel_descr chan_desc;
-
 	/* paging state and control */
 	struct gsm_bts_paging_state paging;
 
@@ -368,6 +366,15 @@ struct gsm_bts {
 		struct gsm_nm_state nm_state;
 	} site_mgr;
 
+	/* parameters from which we build SYSTEM INFORMATION */
+	struct {
+		struct gsm48_rach_control rach_control;
+		u_int8_t ncc_permitted;
+		struct gsm48_cell_sel_par cell_sel_par;
+		struct gsm48_cell_options cell_options;
+		struct gsm48_control_channel_descr chan_desc;
+	} si_common;
+
 	/* ip.accesss Unit ID's have Site/BTS/TRX layout */
 	union {
 		struct {
diff --git a/openbsc/include/openbsc/rest_octets.h b/openbsc/include/openbsc/rest_octets.h
new file mode 100644
index 000000000..4e72c0f87
--- /dev/null
+++ b/openbsc/include/openbsc/rest_octets.h
@@ -0,0 +1,122 @@
+#ifndef _REST_OCTETS_H
+#define _REST_OCTETS_H
+
+#include <sys/types.h>
+#include <openbsc/gsm_04_08.h>
+
+/* generate SI1 rest octets */
+int rest_octets_si1(u_int8_t *data, u_int8_t *nch_pos);
+
+struct gsm48_si_selection_params {
+	u_int16_t penalty_time:5,
+		  temp_offs:3,
+		  cell_resel_off:6,
+		  cbq:1,
+		  present:1;
+};
+
+struct gsm48_si_power_offset {
+	u_int8_t power_offset:2,
+		 present:1;
+};
+
+struct gsm48_si3_gprs_ind {
+	u_int8_t si13_position:1,
+		 ra_colour:3,
+		 present:1;
+};
+
+struct gsm48_lsa_params {
+	u_int32_t prio_thr:3,
+		 lsa_offset:3,
+		 mcc:12,
+		 mnc:12;
+	unsigned int present;
+};
+
+struct gsm48_si_ro_info {
+	struct gsm48_si_selection_params selection_params;
+	struct gsm48_si_power_offset power_offset;
+	u_int8_t si2ter_indicator;
+	u_int8_t early_cm_ctrl;
+	struct {
+		u_int8_t where:3,
+			 present:1;
+	} scheduling;
+	struct gsm48_si3_gprs_ind gprs_ind;
+
+	/* SI 4 specific */
+	struct gsm48_lsa_params lsa_params;
+	u_int16_t cell_id;
+	u_int8_t break_ind;	/* do we have SI7 + SI8 ? */
+};
+
+
+/* Generate SI3 Rest Octests (Chapter 10.5.2.34 / Table 10.4.72) */
+int rest_octets_si3(u_int8_t *data, const struct gsm48_si_ro_info *si3);
+
+/* Generate SI4 Rest Octets (Chapter 10.5.2.35) */
+int rest_octets_si4(u_int8_t *data, const struct gsm48_si_ro_info *si4);
+
+enum pbcch_carrier_type {
+	PBCCH_BCCH,
+	PBCCH_ARFCN,
+	PBCCH_MAIO
+};
+
+/* TS 03.60 Chapter 6.3.3.1: Network Mode of Operation */
+enum gprs_nmo {
+	GPRS_NMO_I	= 0,	/* CS pagin on GPRS paging or traffic channel */
+	GPRS_NMO_II	= 1,	/* all paging on CCCH */
+	GPRS_NMO_III	= 2,	/* no paging coordination */
+};
+
+struct gprs_cell_options {
+	enum gprs_nmo nmo;
+	/* T3168: wait for packet uplink assignment message */
+	u_int32_t t3168;	/* in milliseconds */
+	/* T3192: wait for release of the TBF after reception of the final block */
+	u_int32_t t3192;	/* in milliseconds */
+	u_int32_t drx_timer_max;/* in seconds */
+	u_int32_t bs_cv_max;
+};
+
+/* TS 04.60 Table 12.9.2 */
+struct gprs_power_ctrl_pars {
+	u_int8_t alpha;
+	u_int8_t t_avg_w;
+	u_int8_t t_avg_t;
+	u_int8_t pc_meas_chan;
+	u_int8_t n_avg_i;
+};
+
+struct gsm48_si13_info {
+	struct gprs_cell_options cell_opts;
+	struct gprs_power_ctrl_pars pwr_ctrl_pars;
+	u_int8_t bcch_change_mark;
+	u_int8_t si_change_field;
+	u_int8_t pbcch_present;
+
+	union {
+		struct {
+			u_int8_t rac;
+			u_int8_t spgc_ccch_sup;
+			u_int8_t net_ctrl_ord;
+			u_int8_t prio_acc_thr;
+		} no_pbcch;
+		struct {
+			u_int8_t psi1_rep_per;
+			u_int8_t pb;
+			u_int8_t tsc;
+			u_int8_t tn;
+			enum pbcch_carrier_type carrier_type;
+			u_int16_t arfcn;
+			u_int8_t maio;
+		} pbcch;
+	};
+};
+
+/* Generate SI13 Rest Octests (Chapter 10.5.2.37b) */
+int rest_octets_si13(u_int8_t *data, const struct gsm48_si13_info *si13);
+
+#endif /* _REST_OCTETS_H */
diff --git a/openbsc/include/openbsc/system_information.h b/openbsc/include/openbsc/system_information.h
new file mode 100644
index 000000000..982a9ac63
--- /dev/null
+++ b/openbsc/include/openbsc/system_information.h
@@ -0,0 +1,6 @@
+#ifndef _SYSTEM_INFO_H
+#define _SYSTEM_INFO_H
+
+int gsm_generate_si(u_int8_t *output, struct gsm_bts *bts, int type);
+
+#endif