| /* GPRS SNDCP protocol implementation as per 3GPP TS 04.65 */ |
| |
| /* (C) 2010 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. |
| * |
| */ |
| |
| #include <errno.h> |
| #include <stdint.h> |
| |
| #include <osmocore/msgb.h> |
| #include <osmocore/linuxlist.h> |
| #include <osmocore/timer.h> |
| #include <osmocore/talloc.h> |
| |
| #include <openbsc/gsm_data.h> |
| #include <openbsc/debug.h> |
| #include <openbsc/gprs_bssgp.h> |
| #include <openbsc/gprs_llc.h> |
| |
| /* Chapter 7.2: SN-PDU Formats */ |
| struct sndcp_common_hdr { |
| /* octet 1 */ |
| uint8_t nsapi:4; |
| uint8_t more:1; |
| uint8_t type:1; |
| uint8_t first:1; |
| uint8_t spare:1; |
| /* octet 2 */ |
| uint8_t pcomp; |
| uint8_t dcomp; |
| }; |
| |
| struct sndcp_udata_hdr { |
| /* octet 3 */ |
| uint8_t npdu_high:4; |
| uint8_t seg_nr:4; |
| /* octet 4 */ |
| uint8_t npdu_low; |
| }; |
| |
| /* Entry point for the LL-UNITDATA.indication */ |
| int sndcp_unitdata_ind(struct msgb *msg, uint8_t sapi, uint8_t *hdr, uint8_t len) |
| { |
| struct sndcp_udata_hdr *suh; |
| uint16_t npdu; |
| |
| if (suh->type == 0) { |
| LOGP(DGPRS, LOGL_ERROR, "SN-DATA PDU at unitdata_ind() function\n"); |
| return -EINVAL; |
| } |
| |
| npdu = (suh->npdu_high << 8) | suh->npdu_low; |
| } |
| |