Added interpretation of neighbour cells from SI2bis and SI2ter messages.
Removed code borrowed from Wireshark replacing it with libosmocore's function.
diff --git a/lib/misc_utils/extract_system_info_impl.cc b/lib/misc_utils/extract_system_info_impl.cc
index 0dc43a6..846c87a 100644
--- a/lib/misc_utils/extract_system_info_impl.cc
+++ b/lib/misc_utils/extract_system_info_impl.cc
@@ -33,6 +33,10 @@
#include <iostream>
#include <endian.h>
#include <boost/foreach.hpp>
+extern "C" {
+ #include <osmocom/gsm/gsm48_ie.h>
+}
+
#include "extract_system_info_impl.h"
@@ -62,6 +66,7 @@
uint8_t * message_plus_header = (uint8_t *)pmt::blob_data(message_plus_header_blob);
gsmtap_hdr * header = (gsmtap_hdr *)message_plus_header;
uint8_t * msg_elements = (uint8_t *)(message_plus_header+sizeof(gsmtap_hdr));
+ struct gsm_sysinfo_freq freq[1024];
if(msg_elements[2]==0x1b){
chan_info info;
@@ -90,25 +95,60 @@
} else {
d_c0_channels[info.id] = info;
}
- } else if(msg_elements[2]==0x1a){ //System Information Type 2
+ }
+ else if(msg_elements[2]==0x1a){ //System Information Type 2
+ memset(freq, 0, sizeof(freq));
chan_info info;
info.id = be16toh(header->arfcn); //take arfcn
info.pwr_db = header->signal_dbm;
boost::mutex::scoped_lock lock(extract_mutex);
//read neighbour cells
- decode_neighbour_cells(msg_elements, 3, info.id);
-// unsigned int byte_nr, arfcn, bit;
-// arfcn=124;
-// bit=4;
-// for (byte_nr = 0; byte_nr <= 15; byte_nr++) {
-// while (bit-- != 0) {
-// if (((msg_elements[byte_nr+3] >> bit) & 1) == 1){
-// d_c0_channels[info.id].neighbour_cells.insert(arfcn);
-// }
-// arfcn--;
-// }
-// bit=8;
-// }
+ gsm48_decode_freq_list(freq, &msg_elements[3], 16, 0xce, 0x01);
+ for(int arfcn=0; arfcn<sizeof(freq); arfcn++){
+ if(freq[arfcn].mask==0x01){
+ d_c0_channels[info.id].neighbour_cells.insert(arfcn);
+ }
+ }
+
+ if(d_c0_channels.find(info.id) != d_c0_channels.end()){
+ d_c0_channels[info.id].copy_nonzero_elements(info);
+ } else {
+ d_c0_channels[info.id] = info;
+ }
+ }
+ else if(msg_elements[2]==0x02){ //System Information Type 2bis
+ memset(freq, 0, sizeof(freq));
+ chan_info info;
+ info.id = be16toh(header->arfcn); //take arfcn
+ info.pwr_db = header->signal_dbm;
+ boost::mutex::scoped_lock lock(extract_mutex);
+ //read neighbour cells
+ gsm48_decode_freq_list(freq, &msg_elements[3], 16, 0xce, 0x01);
+ for(int arfcn=0; arfcn<sizeof(freq); arfcn++){
+ if(freq[arfcn].mask==0x01){
+ d_c0_channels[info.id].neighbour_cells.insert(arfcn);
+ }
+ }
+
+ if(d_c0_channels.find(info.id) != d_c0_channels.end()){
+ d_c0_channels[info.id].copy_nonzero_elements(info);
+ } else {
+ d_c0_channels[info.id] = info;
+ }
+ }
+ else if(msg_elements[2]==0x03){ //System Information Type 2ter
+ memset(freq, 0, sizeof(freq));
+ chan_info info;
+ info.id = be16toh(header->arfcn); //take arfcn
+ info.pwr_db = header->signal_dbm;
+ boost::mutex::scoped_lock lock(extract_mutex);
+ //read neighbour cells
+ gsm48_decode_freq_list(freq, &msg_elements[3], 16, 0x8e, 0x01);
+ for(int arfcn=0; arfcn<sizeof(freq); arfcn++){
+ if(freq[arfcn].mask==0x01){
+ d_c0_channels[info.id].neighbour_cells.insert(arfcn);
+ }
+ }
if(d_c0_channels.find(info.id) != d_c0_channels.end()){
d_c0_channels[info.id].copy_nonzero_elements(info);
@@ -118,158 +158,6 @@
}
}
- void extract_system_info_impl::decode_neighbour_cells(uint8_t * data, unsigned int offset, unsigned int chan_id)
- {
- unsigned int curr_offset, byte, bit, arfcn, format;
- uint8_t oct;
- curr_offset = offset;
- format = data[curr_offset];
-
- if ((format & 0xc0) == 0x00)
- {
- /* bit map 0 */
- bit = 4;
- arfcn = 125;
- for (byte = 0; byte <= 15; byte++)
- {
- oct = data[curr_offset];
- while (bit-- != 0)
- {
- arfcn--;
- if (((oct >> bit) & 1) == 1)
- {
- d_c0_channels[chan_id].neighbour_cells.insert(arfcn);
- }
- }
- bit = 8;
- curr_offset++;
- }
- }
- else if ((format & 0xc8) == 0x80)
- {
- /* 1024 range */
-// dissect_channel_list_n_range(tvb, tree, pinfo, curr_offset, len, 1024);
- }
- else if ((format & 0xce) == 0x88)
- {
- /* 512 range */
-// dissect_channel_list_n_range(tvb, tree, pinfo, curr_offset, len, 512);
- }
- else if ((format & 0xce) == 0x8a)
- {
- /* 256 range */
-// dissect_channel_list_n_range(tvb, tree, pinfo, curr_offset, len, 256);
- }
- else if ((format & 0xce) == 0x8c)
- {
- /* 128 range */
-// dissect_channel_list_n_range(tvb, tree, pinfo, curr_offset, len, 128);
- }
- else if ((format & 0xce) == 0x8e)
- {
- /* variable bit map */
- arfcn = ((format & 0x01) << 9) | (data[curr_offset+1] << 1) | ((data[curr_offset+2] & 0x80) >> 7);
- curr_offset = curr_offset + 2;
- bit = 7;
- for(byte = 0; byte <= (15-2); byte++){
- oct = data[curr_offset];
- while (bit-- != 0){
- arfcn++;
- if (((oct >> bit) & 1) == 1){
- d_c0_channels[chan_id].neighbour_cells.insert(arfcn);
- }
- }
- bit = 8;
- curr_offset++;
- }
- }
-
- return;
- }
-
-// void extract_system_info_impl::dissect_channel_list_n_range(guint32 offset, guint len, gint range)
-// {
-// int curr_offset = offset, bit_offset, f0, arfcn_orig, w[64], wsize, i;
-// int octet, nwi = 1, jwi=0, imax, iused, arfcn;
-// uint8_t list[1024];
-
-// memset((void*)list,0,sizeof(list));
-
-//// subtree = proto_tree_add_subtree_format(tree,tvb, curr_offset, len,
-//// ett_gsm_rr_elem[DE_RR_NEIGH_CELL_DESC], NULL, "Range %d format", range);
-
-// octet = data[curr_offset];
-// if (range == 1024) {
-// f0 = (octet>>2)&1;
-// if (f0)
-// list[0] = 1;
-// arfcn_orig = 0;
-// wsize = 10;
-// imax = 16;
-// bit_offset = curr_offset*8 + 6;
-// }
-// else {
-// bit_offset = curr_offset*8 + 7;
-// arfcn_orig = (gint) tvb_get_bits(tvb, bit_offset, 10, FALSE);
-//// proto_tree_add_bits_item(subtree, hf_n_range_orig_arfcn, tvb, bit_offset, 10, ENC_BIG_ENDIAN);
-// bit_offset+=10;
-
-// list[arfcn_orig] = 1;
-
-// switch (range) {
-// case 512:
-// wsize=9;
-// imax = 17;
-// break;
-// case 256:
-// wsize=8;
-// imax = 21;
-// break;
-// case 128:
-// wsize=7;
-// imax = 28;
-// break;
-// default:
-//// DISSECTOR_ASSERT_NOT_REACHED();
-// }
-// }
-// iused = imax; /* in case the list is actually full */
-
-// /* extract the variable size w[] elements */
-// for (i=1; i<=imax; i++) {
-// w[i] = (gint) tvb_get_bits(tvb, bit_offset, wsize, FALSE);
-//// proto_tree_add_text(subtree, tvb, bit_offset>>3, ((bit_offset+wsize-1)>>3) - (bit_offset>>3) + 1 , "%s %s(%d): %d",
-//// decode_bits_in_field(bit_offset, wsize, w[i]),
-//// "W",
-//// i,
-//// w[i]);
-// bit_offset += wsize;
-// curr_offset = bit_offset>>3;
-
-// if ((iused == imax) && (w[i] == 0) ) {
-// iused = i - 1;
-// }
-// if ((curr_offset-offset)>len) {
-// iused = i - 1;
-// break;
-// }
-// if (++jwi == nwi) { /* check if the number of wi at this wsize has been extracted */
-// jwi = 0; /* reset the count of wi at this size */
-// nwi <<= 1; /* get twice as many of the next size */
-// wsize--; /* make the next size 1 bit smaller */
-// }
-// }
-
-// for (i=1; i<=iused; i++) {
-// arfcn = (f_k(i, w, range) + arfcn_orig)%1024;
-// list[arfcn] = 1;
-// }
-
-//// display_channel_list(list, tvb, tree, offset, curr_offset-offset);
-
-// return;
-// }
-
std::vector<int> extract_system_info_impl::get_chans()
{
std::vector<int> chans_ids;