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.

1 files changed, 52 insertions, 277 deletions

diff --git a/openbsc/src/bsc_init.c b/openbsc/src/bsc_init.c
index 153e024e4..d21f71a0c 100644
--- a/openbsc/src/bsc_init.c
+++ b/openbsc/src/bsc_init.c
@@ -28,6 +28,7 @@
 #include <openbsc/debug.h>
 #include <openbsc/misdn.h>
 #include <openbsc/telnet_interface.h>
+#include <openbsc/system_information.h>
 #include <openbsc/paging.h>
 #include <openbsc/signal.h>
 #include <openbsc/talloc.h>
@@ -37,7 +38,6 @@ extern struct gsm_network *bsc_gsmnet;
 extern int ipacc_rtp_direct;
 
 static void patch_nm_tables(struct gsm_bts *bts);
-static void patch_si_tables(struct gsm_bts *bts);
 
 /* The following definitions are for OM and NM packets that we cannot yet
  * generate by code but we just pass on */
@@ -667,219 +667,42 @@ int bsc_shutdown_net(struct gsm_network *net)
 	return 0;
 }
 
-struct bcch_info {
-	u_int8_t type;
-	u_int8_t len;
-	const u_int8_t *data;
-};
-
-/*
-SYSTEM INFORMATION TYPE 1
-  Cell channel description
-    Format-ID bit map 0
-    CA-ARFCN Bit 124...001 (Hex): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01
-  RACH Control Parameters
-    maximum 7 retransmissions
-    8 slots used to spread transmission
-    cell not barred for access
-    call reestablishment not allowed
-    Access Control Class = 0000
-*/
-static u_int8_t si1[] = {
-	/* header */0x55, 0x06, 0x19,
-	/* ccdesc */0x04 /*0x00*/, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 /*0x01*/,
-	/* rach */0xD5, 0x04, 0x00,
-	/* s1 reset*/0x2B
-};
-
-/*
- SYSTEM INFORMATION TYPE 2
-  Neighbour Cells Description
-    EXT-IND: Carries the complete BA
-    BA-IND = 0
-    Format-ID bit map 0
-    CA-ARFCN Bit 124...001 (Hex): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
-  NCC permitted (NCC) = FF
-  RACH Control Parameters
-    maximum 7 retransmissions
-    8 slots used to spread transmission
-    cell not barred for access
-    call reestablishment not allowed
-    Access Control Class = 0000
-*/
-static u_int8_t si2[] = {
-	/* header */0x59, 0x06, 0x1A,
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-	/* ncc */0xFF,
-	/* rach*/0xD5, 0x04, 0x00
-};
-
-/*
-SYSTEM INFORMATION TYPE 3
-  Cell identity = 00001 (1h)
-  Location area identification
-    Mobile Country Code (MCC): 001
-    Mobile Network Code (MNC): 01
-    Location Area Code  (LAC): 00001 (1h)
-  Control Channel Description
-    Attach-detach: MSs in the cell are not allowed to apply IMSI attach /detach
-    0 blocks reserved for access grant
-    1 channel used for CCCH, with SDCCH
-    5 multiframes period for PAGING REQUEST
-    Time-out T3212 = 0
-  Cell Options BCCH
-    Power control indicator: not set
-    MSs shall not use uplink DTX
-    Radio link timeout = 36
-  Cell Selection Parameters
-    Cell reselect hysteresis = 6 dB RXLEV hysteresis for LA re-selection
-    max.TX power level MS may use for CCH = 2 <- according to GSM05.05 39dBm (max)
-    Additional Reselect Parameter Indication (ACS) = only SYSTEM INFO 4: The SI rest octets, if present, shall be used to derive the value of PI and possibly C2 parameters
-    Half rate support (NECI): New establishment causes are not supported
-    min.RX signal level for MS = 0
-  RACH Control Parameters
-    maximum 7 retransmissions
-    8 slots used to spread transmission
-    cell not barred for access
-    call reestablishment not allowed
-    Access Control Class = 0000
-  SI 3 Rest Octets (not present)
-*/
-static u_int8_t si3[] = {
-	/* header */0x49, 0x06, 0x1B,
-	/* cell */0x00, 0x01,
-	/* lai  */0x00, 0xF1, 0x10, 0x00, 0x01,
-	/* desc */0x01, 0x03, 0x00,
-	/* option*/0x28,
-	/* selection*/0x62, 0x00,
-	/* rach */0xD5, 0x04, 0x00,
-	/* rest */ 0x2B, 0x2B, 0x2B, 0x2B
-};
-
-/*
-SYSTEM INFORMATION TYPE 4
-  Location area identification
-    Mobile Country Code (MCC): 001
-    Mobile Network Code (MNC): 01
-    Location Area Code  (LAC): 00001 (1h)
-  Cell Selection Parameters
-    Cell reselect hysteresis = 6 dB RXLEV hysteresis for LA re-selection
-    max.TX power level MS may use for CCH = 2
-    Additional Reselect Parameter Indication (ACS) = only SYSTEM INFO 4: The SI rest octets, if present, shall be used to derive the value of PI and possibly C2 parameters
-    Half rate support (NECI): New establishment causes are not supported
-    min.RX signal level for MS = 0
-  RACH Control Parameters
-    maximum 7 retransmissions
-    8 slots used to spread transmission
-    cell not barred for access
-    call reestablishment not allowed
-    Access Control Class = 0000
-  CBCH Channel Description
-    Type = SDCCH/4[2]
-    Timeslot Number: 0
-    Training Sequence Code: 7h
-    ARFCN: 1
-  SI Rest Octets (not present)
-*/
-static u_int8_t si4[] = {
-	/* header */0x41, 0x06, 0x1C,
-	/* lai */0x00, 0xF1, 0x10, 0x00, 0x01,
-	/* sel */0x62, 0x00,
-	/* rach*/0xD5, 0x04, 0x00,
-	/* cbch chan desc */ 0x64, 0x30, 0xE0, HARDCODED_ARFCN/*0x01*/,
-	/* rest octets */ 0x2B, 0x2B, 0x2B, 0x2B, 0x2B, 0x2B
-};
-
-/*
- SYSTEM INFORMATION TYPE 5
-  Neighbour Cells Description
-    EXT-IND: Carries the complete BA
-    BA-IND = 0
-    Format-ID bit map 0
-    CA-ARFCN Bit 124...001 (Hex): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
-*/
-
-static u_int8_t si5[] = {
-	/* header without l2 len*/0x06, 0x1D,
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-};
-
-// SYSTEM INFORMATION TYPE 6
-
-/*
-SACCH FILLING
-  System Info Type: SYSTEM INFORMATION 6
-  L3 Information (Hex): 06 1E 00 01 xx xx 10 00 01 28 FF
-
-SYSTEM INFORMATION TYPE 6
-  Cell identity = 00001 (1h)
-  Location area identification
-    Mobile Country Code (MCC): 001
-    Mobile Network Code (MNC): 01
-    Location Area Code  (LAC): 00001 (1h)
-  Cell Options SACCH
-    Power control indicator: not set
-    MSs shall not use uplink DTX on a TCH-F. MS shall not use uplink DTX on TCH-H.
-    Radio link timeout = 36
-  NCC permitted (NCC) = FF
-*/
-
-static u_int8_t si6[] = {
-	/* header */0x06, 0x1E,
-	/* cell id*/ 0x00, 0x01,
-	/* lai */ 0x00, 0xF1, 0x10, 0x00, 0x01,
-	/* options */ 0x28,
-	/* ncc */ 0xFF,
-};
-
-
-
-static const struct bcch_info bcch_infos[] = {
-	{
-		.type = RSL_SYSTEM_INFO_1,
-		.len = sizeof(si1),
-		.data = si1,
-	}, {
-		.type = RSL_SYSTEM_INFO_2,
-		.len = sizeof(si2),
-		.data = si2,
-	}, {
-		.type = RSL_SYSTEM_INFO_3,
-		.len = sizeof(si3),
-		.data = si3,
-	}, {
-		.type = RSL_SYSTEM_INFO_4,
-		.len = sizeof(si4),
-		.data = si4,
-	},
-};
-
-static_assert(sizeof(si1) == sizeof(struct gsm48_system_information_type_1), type1)
-static_assert(sizeof(si2) == sizeof(struct gsm48_system_information_type_2), type2)
-static_assert(sizeof(si3) == sizeof(struct gsm48_system_information_type_3), type3)
-static_assert(sizeof(si4) >= sizeof(struct gsm48_system_information_type_4), type4)
-static_assert(sizeof(si5) == sizeof(struct gsm48_system_information_type_5), type5)
-static_assert(sizeof(si6) >= sizeof(struct gsm48_system_information_type_6), type6)
-
 /* set all system information types */
 static int set_system_infos(struct gsm_bts_trx *trx)
 {
-	int i;
+	int i, rc;
+	u_int8_t si_tmp[23];
 
 	if (trx == trx->bts->c0) {
-		for (i = 0; i < ARRAY_SIZE(bcch_infos); i++) {
-			rsl_bcch_info(trx, bcch_infos[i].type,
-				      bcch_infos[i].data,
-				      bcch_infos[i].len);
+		for (i = 1; i <= 4; i++) {
+			rc = gsm_generate_si(si_tmp, trx->bts, i);
+			if (rc < 0)
+				goto err_out;
+			rsl_bcch_info(trx, i, si_tmp, sizeof(si_tmp));
 		}
 	}
-	rsl_sacch_filling(trx, RSL_SYSTEM_INFO_5, si5, sizeof(si5));
-	rsl_sacch_filling(trx, RSL_SYSTEM_INFO_6, si6, sizeof(si6));
+#ifdef GPRS
+	rc = gsm_generate_si(si_tmp, trx->bts, RSL_SYSTEM_INFO_13);
+	if (rc < 0)
+		goto err_out;
+	rsl_bcch_info(trx, RSL_SYSTEM_INFO_13, si_tmp, rc);
+#endif
+	rc = gsm_generate_si(si_tmp, trx->bts, 5);
+	if (rc < 0)
+		goto err_out;
+	rsl_sacch_filling(trx, RSL_SYSTEM_INFO_5, si_tmp, rc);
+
+	rc = gsm_generate_si(si_tmp, trx->bts, 6);
+	if (rc < 0)
+		goto err_out;
+	rsl_sacch_filling(trx, RSL_SYSTEM_INFO_6, si_tmp, rc);
 
 	return 0;
+err_out:
+	fprintf(stderr, "Cannot generate SI for BTS %u, most likely "
+		"a problem with neighbor cell list generation\n",
+		trx->bts->nr);
+	return rc;
 }
 
 /*
@@ -913,81 +736,12 @@ static void patch_nm_tables(struct gsm_bts *bts)
 	nanobts_attr_radio[1] = bts->c0->max_power_red / 2;
 }
 
-/*
- * Patch the various SYSTEM INFORMATION tables to update
- * the LAI
- */
-static void patch_si_tables(struct gsm_bts *bts)
-{
-	u_int8_t arfcn_low = bts->c0->arfcn & 0xff;
-	u_int8_t arfcn_high = (bts->c0->arfcn >> 8) & 0x0f;
-
-	/* covert the raw packet to the struct */
-	struct gsm48_system_information_type_1 *type_1 =
-		(struct gsm48_system_information_type_1*)&si1;
-	struct gsm48_system_information_type_2 *type_2 =
-		(struct gsm48_system_information_type_2*)&si2;
-	struct gsm48_system_information_type_3 *type_3 =
-		(struct gsm48_system_information_type_3*)&si3;
-	struct gsm48_system_information_type_4 *type_4 =
-		(struct gsm48_system_information_type_4*)&si4;
-	struct gsm48_system_information_type_6 *type_6 =
-		(struct gsm48_system_information_type_6*)&si6;
-	struct gsm48_loc_area_id lai;
-
-	gsm0408_generate_lai(&lai, bts->network->country_code,
-			     bts->network->network_code,
-			     bts->location_area_code);
-
-	/* assign the MCC and MNC */
-	type_3->lai = lai;
-	type_4->lai = lai;
-	type_6->lai = lai;
-
-	/* set the CI */
-	type_3->cell_identity = htons(bts->cell_identity);
-	type_6->cell_identity = htons(bts->cell_identity);
-
-	type_4->data[2] &= 0xf0;
-	type_4->data[2] |= arfcn_high;
-	type_4->data[3] = arfcn_low;
-
-	/* patch Control Channel Description 10.5.2.11 */
-	type_3->control_channel_desc = bts->chan_desc;
-
-	/* patch TSC */
-	si4[15] &= ~0xe0;
-	si4[15] |= (bts->tsc & 7) << 5;
-
-	/* patch MS max power for CCH */
-	type_4->cell_sel_par.ms_txpwr_max_ccch =
-			ms_pwr_ctl_lvl(bts->band, bts->ms_max_power);
-
-	/* Set NECI to influence channel request */
-	type_3->cell_sel_par.neci = bts->network->neci;
-	type_4->cell_sel_par.neci = bts->network->neci;
-
-	if (bts->cell_barred) {
-		type_1->rach_control.cell_bar = 1;
-		type_2->rach_control.cell_bar = 1;
-		type_3->rach_control.cell_bar = 1;
-		type_4->rach_control.cell_bar = 1;
-	} else {
-		type_1->rach_control.cell_bar = 0;
-		type_2->rach_control.cell_bar = 0;
-		type_3->rach_control.cell_bar = 0;
-		type_4->rach_control.cell_bar = 0;
-	}
-}
-
-
 static void bootstrap_rsl(struct gsm_bts_trx *trx)
 {
 	fprintf(stdout, "bootstrapping RSL for BTS/TRX (%u/%u) "
 		"using MCC=%u MNC=%u BSIC=%u TSC=%u\n",
 		trx->bts->nr, trx->nr, bsc_gsmnet->country_code,
 		bsc_gsmnet->network_code, trx->bts->bsic, trx->bts->tsc);
-	patch_si_tables(trx->bts);
 	set_system_infos(trx);
 }
 
@@ -1042,11 +796,32 @@ static int bootstrap_bts(struct gsm_bts *bts)
 	}
 
 	/* Control Channel Description */
-	bts->chan_desc.att = 1;
-	bts->chan_desc.ccch_conf = RSL_BCCH_CCCH_CONF_1_C;
-	bts->chan_desc.bs_pa_mfrms = RSL_BS_PA_MFRMS_5;
+	bts->si_common.chan_desc.att = 1;
+	bts->si_common.chan_desc.ccch_conf = RSL_BCCH_CCCH_CONF_1_C;
+	bts->si_common.chan_desc.bs_pa_mfrms = RSL_BS_PA_MFRMS_5;
+	if (bts->cell_barred)
+		bts->si_common.rach_control.cell_bar = 1;
 	/* T3212 is set from vty/config */
 
+	/* some defaults for our system information */
+	bts->si_common.rach_control.re = 1; /* no re-establishment */
+	bts->si_common.rach_control.tx_integer = 5; /* 8 slots spread */
+	bts->si_common.rach_control.max_trans = 3; /* 7 retransmissions */
+	bts->si_common.rach_control.t2 = 4; /* no emergency calls */
+
+	bts->si_common.cell_options.radio_link_timeout = 2; /* 12 */
+	bts->si_common.cell_options.dtx = 2; /* MS shall not use upplink DTX */
+	bts->si_common.cell_options.pwrc = 0; /* PWRC not set */
+
+	bts->si_common.cell_sel_par.ms_txpwr_max_ccch =
+			ms_pwr_ctl_lvl(bts->band, bts->ms_max_power);
+	bts->si_common.cell_sel_par.cell_resel_hyst = 2; /* 4 dB */
+	bts->si_common.cell_sel_par.rxlev_acc_min = 0;
+	bts->si_common.cell_sel_par.acs = 0;
+	bts->si_common.cell_sel_par.neci = bts->network->neci;
+
+	bts->si_common.ncc_permitted = 0xff;
+
 	paging_init(bts);
 
 	return 0;