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/* |
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ROHC Project 2003 at Lulea University of Technology, Sweden. |
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Authors: Andreas Vernersson <andver-8@student.luth.se> |
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Daniel Pettersson <danpet-7@student.luth.se> |
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Erik Soderstrom <soderstrom@yahoo.com> |
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Fredrik Lindstrom <frelin-9@student.luth.se> |
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Johan Stenmark <johste-8@student.luth.se> |
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Martin Juhlin <juhlin@users.sourceforge.net> |
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Mikael Larsson <larmik-9@student.luth.se> |
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Robert Maxe <robmax-1@student.luth.se> |
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|
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Copyright (C) 2003 Andreas Vernersson, Daniel Pettersson, |
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Erik Soderström, Fredrik Lindström, Johan Stenmark, |
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Martin Juhlin, Mikael Larsson, Robert Maxe. |
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|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2 of the License, or |
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(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program; if not, write to the Free Software |
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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*/ |
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// IP-Only profile in decompressor |
31 |
|
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/* The decode functions decode the packet, control CRC |
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* and if crc-fails the try a new decompression with a |
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* other SN number. The decode functions returns some |
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* kind of ROHC_ERROR or if it is correct decoded the |
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* length of the decoded packet is returned. |
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*/ |
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|
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#include <asm/byteorder.h> |
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|
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#include "rohc.h" |
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#include "decomp.h" |
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|
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#include "d_ip.h" |
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#include "d_util.h" |
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#include "comp.h" |
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#include "c_util.h" |
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|
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//--------------------------------------------------------- Helpfunctions |
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|
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/* Decode a UO-0 package */ |
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static int decode_uo0( |
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struct sd_rohc * state, |
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struct sd_context * context, |
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unsigned char * head, |
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unsigned char * src, |
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unsigned char * dest, |
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int payload_size |
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); |
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|
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/* Decode a UO-1 package */ |
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static int decode_uo1( |
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struct sd_rohc * state, |
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struct sd_context * context, |
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unsigned char * head, |
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unsigned char * src2, |
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unsigned char * dest, |
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int payload_size |
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); |
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|
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/* Decode a UO-2 package */ |
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static int decode_uor2( |
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struct sd_rohc * state, |
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struct sd_context * context, |
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unsigned char * head, |
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unsigned char * src2, |
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unsigned char * dest, |
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int payload_size |
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); |
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|
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/* Decode a IR-Dyn package */ |
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static int decode_irdyn( |
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struct sd_rohc * state, |
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struct sd_context * context, |
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unsigned char * head, |
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unsigned char * src2, |
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unsigned char * dest, |
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int payload_size |
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); |
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|
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/* Decode extention 0 */ |
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static int decode_extention0(unsigned char * src, int * sn, int * ip_id); |
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|
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/* Decode extention 1 */ |
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static int decode_extention1(unsigned char * src, int * sn, int * ip_id); |
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|
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/* Decode extention 2 */ |
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static int decode_extention2(unsigned char * src, int * sn, int * ip_id, int * ip_id2); |
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|
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/* Decode extention 3 |
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* - Updates random fields in the s_iponly_change |
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* - May update the SN value with 8 lower bits. sn_size is then changed |
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*/ |
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static int decode_extention3(unsigned char * src, struct sd_context * context, struct sd_rohc *state, |
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int * sn, int * sn_size, int * ip_id_changed, int * id2_updated); |
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|
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// Make a copy of the "active"-struct to the "last"-struct. |
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static void syncronize(struct s_iponly_profile_data *); |
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|
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// Decode package type |
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static int package_type(const unsigned char * p); |
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|
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/* Deceide the extention type */ |
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static int extention_type(const unsigned char * p); |
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|
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/* Write a uncompressed IP v4 header */ |
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static void write_uncompressed_ip4( |
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struct s_iponly_change * active1, |
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int ip_id, |
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unsigned char * dest, |
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int payload_size |
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); |
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|
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|
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/* Copy the last-struct to active-struct. */ |
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static void sync_on_failure(struct s_iponly_profile_data * pro); |
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|
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/* Decode inner IP flags and fields. Storage the values |
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* in a IP-head struct. |
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*/ |
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static int decode_inner_header_flags( |
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unsigned char * flags, |
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unsigned char * fields, |
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struct iphdr * ip, |
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int * rnd, int * nbo); |
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|
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/* Decode outer IP flags and fields. Storage the values |
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* in a IP-head struct. |
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*/ |
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static int decode_outer_header_flags( |
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unsigned char * flags, |
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unsigned char * fields, |
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struct iphdr * ip, |
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int * rnd, int * nbo, |
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int * ip_changed); |
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|
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/* A functions that decode uo0 and uo1 packets |
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* |
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*/ |
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static int help_to_decode_uo0_and_uo1( |
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struct sd_context * context, |
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unsigned char * src, |
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unsigned char * dest, |
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int * payload_size, |
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int sn_bits, |
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int number_of_sn_bits, |
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int * id, |
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int number_of_id_bits, |
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int * id2, |
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int * sn, |
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int * calc_crc |
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); |
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|
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/* A functions that decode uor2 packets |
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* |
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*/ |
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static int help_to_decode_uor2( |
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struct sd_rohc * state, |
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struct sd_context * context, |
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unsigned char * src2, |
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unsigned char * dest, |
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int * payload_size, |
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int * id, |
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int * id2, |
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int * sn, |
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int * sn_size, |
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int sn_bits, |
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int ext, |
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int * calc_crc |
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); |
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|
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/* The function that try to correct a packet after |
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* a crc-failure. |
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* It try with an other SN value. |
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*/ |
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static int act_on_crc_failure( |
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struct sd_rohc * state, |
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struct sd_context * context, |
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unsigned char * src, |
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unsigned char * dest, |
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int sn_size, |
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int * sn_curr1, |
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int sn_bits, |
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int * payload_size, |
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int * id, |
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int id_size, |
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int * id2, |
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int * calc_crc, |
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int * real_crc, |
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int ext |
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); |
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|
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static void update_inter_packet(struct s_iponly_profile_data * pro); |
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//---------------------------------------------------------- Code |
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|
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// To allocate profile data |
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void * iponly_allocate_decode_data(void) |
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{ |
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struct s_iponly_profile_data * data; |
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struct s_iponly_change * ch; |
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void * p = kmalloc(sizeof(struct s_iponly_profile_data) + 4 * sizeof(struct s_iponly_change), |
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GFP_ATOMIC); |
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|
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if (p==NULL) { |
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rohc_debugf(0, "iponly_allocate_decode_data(): no mem for ip profile data\n"); |
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return NULL; |
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} |
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|
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data = (struct s_iponly_profile_data *)p; |
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ch = (struct s_iponly_change *)(data + 1); |
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|
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memset(p, 0, sizeof(struct s_iponly_profile_data) + |
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4 * sizeof(struct s_iponly_change) ); |
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|
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data->last1 = ch; ch++; |
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data->active1 = ch; ch++; |
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data->last2 = ch; ch++; |
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data->active2 = ch; |
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|
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return p; |
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} |
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|
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// To deallocate profile data |
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void iponly_free_decode_data(void * p) |
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{ |
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kfree(p); |
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} |
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|
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// Decode an IR-package and initalize context |
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int iponly_decode_ir( |
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struct sd_rohc * state, |
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struct sd_context * context, |
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unsigned char * src, |
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int copy_size, |
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int dynamic_present, |
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unsigned char * dest |
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) |
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{ |
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struct s_iponly_profile_data * pro = context->data; |
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struct s_iponly_change * active1 = pro->active1; |
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struct s_iponly_change * active2 = pro->active2; |
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|
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unsigned char * s = src; |
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unsigned char * d = dest; |
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|
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int size, sn; |
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|
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pro->current_packet_time = get_microseconds(); |
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|
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// Ip4 static |
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size = d_decode_static_ip4(s, &active1->ip); |
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|
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if (active1->ip.protocol == PROTOCOL_IP_IN_IP){ |
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pro->multiple_ip = 1; |
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rohc_debugf(1, "Multiple IP header\n"); |
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}else{ |
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pro->multiple_ip = 0; |
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} |
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|
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if (size == -1) { |
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return ROHC_ERROR; |
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} |
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s += size; copy_size -= size; |
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|
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// If multiple-ip-header |
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if(pro->multiple_ip){ |
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size = d_decode_static_ip4(s, &active2->ip); |
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s += size; copy_size -= size; |
279 |
if (size == -1) { |
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return ROHC_ERROR; |
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} |
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} |
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|
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// Dynamic field |
285 |
if (dynamic_present) { |
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size = d_decode_dynamic_ip4(s, &active1->ip, &active1->rnd, &active1->nbo); |
287 |
s += size; copy_size -= (size + 2); |
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|
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// If multiple-ip-header |
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if(pro->multiple_ip){ |
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size = d_decode_dynamic_ip4(s, &active2->ip, &active2->rnd, &active2->nbo); |
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s += size; copy_size -= size; |
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} |
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// Reset the correction-counter |
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pro->counter = 0; |
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|
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// Get and set SN |
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sn = ntohs(* ((__u16 *)s)); |
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d_lsb_init(&pro->sn, sn, -1); |
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d_ip_id_init(&pro->ip_id1, ntohs(active1->ip.id), sn); |
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s += 2; |
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context->state = ROHC_FULL_CONTEXT; |
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|
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// If multiple-ip-header |
305 |
if(pro->multiple_ip){ |
306 |
d_ip_id_init(&pro->ip_id2, ntohs(active2->ip.id), sn); |
307 |
} |
308 |
|
309 |
|
310 |
} else if (context->state != ROHC_FULL_CONTEXT) { |
311 |
// in static/no context and not get dynamic part |
312 |
return ROHC_ERROR; |
313 |
} |
314 |
|
315 |
|
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// Header write |
317 |
if (pro->multiple_ip){ |
318 |
write_uncompressed_ip4(active1, ntohs(active1->ip.id), d, copy_size+sizeof(struct iphdr)); |
319 |
d += sizeof(struct iphdr); |
320 |
write_uncompressed_ip4(active2, ntohs(active2->ip.id), d, copy_size); |
321 |
|
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}else{ |
323 |
write_uncompressed_ip4(active1, ntohs(active1->ip.id), d, copy_size); |
324 |
} |
325 |
d += sizeof(struct iphdr); |
326 |
|
327 |
// Syncronizerar strukterna |
328 |
syncronize(pro); |
329 |
|
330 |
// Update the inter-packet variable |
331 |
update_inter_packet(pro); |
332 |
|
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// Copy payload |
334 |
if (copy_size == 0) return ROHC_OK_NO_DATA; |
335 |
|
336 |
memcpy(d, s, copy_size); |
337 |
|
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// Statistics: |
339 |
context->header_compressed_size += s - src; |
340 |
c_add_wlsb(context->header_16_compressed, 0,0, s - src); |
341 |
context->header_uncompressed_size += (pro->multiple_ip+1)*sizeof(struct iphdr); |
342 |
c_add_wlsb(context->header_16_uncompressed, 0, 0, (pro->multiple_ip+1)*sizeof(struct iphdr)); |
343 |
|
344 |
return copy_size + (pro->multiple_ip + 1) * sizeof(struct iphdr); |
345 |
} |
346 |
|
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// Calculate the size of data in an IR-package. |
348 |
// return : size or zero. |
349 |
int iponly_detect_ir_size(unsigned char * first_byte, int second_byte_add) |
350 |
{ |
351 |
int ret = 10; |
352 |
int d = GET_BIT_0(first_byte); |
353 |
if (d) ret += 5 + 2; |
354 |
if (first_byte[second_byte_add + 2] != 0x40) return 0; |
355 |
if (first_byte[second_byte_add + 3] == PROTOCOL_IP_IN_IP){ |
356 |
ret += 10; |
357 |
if (d) ret += 5; |
358 |
if (first_byte[second_byte_add + 12] != 0x40) return 0; |
359 |
} |
360 |
return ret; |
361 |
} |
362 |
|
363 |
// Calculate the size of data in an IR-package. |
364 |
// return : size or zero. |
365 |
int iponly_detect_ir_dyn_size(unsigned char * first_byte, struct sd_context *c) |
366 |
{ |
367 |
struct s_iponly_profile_data * pro = c->data; |
368 |
if (pro->active1->ip.protocol == PROTOCOL_IP_IN_IP) return 12; |
369 |
return 7; |
370 |
} |
371 |
|
372 |
// Decode all package except IR-package. |
373 |
int iponly_decode( |
374 |
struct sd_rohc * state, |
375 |
struct sd_context * context, |
376 |
unsigned char * src, |
377 |
int size, |
378 |
int second_byte, |
379 |
unsigned char * dest |
380 |
) |
381 |
{ |
382 |
struct s_iponly_profile_data * pro = context->data; |
383 |
// ---- DEBUG ---- |
384 |
int i; unsigned char * p; |
385 |
|
386 |
struct s_iponly_change * active1 = pro->active1; |
387 |
struct s_iponly_change * active2 = pro->active2; |
388 |
struct s_iponly_change * last1 = pro->last1; |
389 |
struct s_iponly_change * last2 = pro->last2; |
390 |
|
391 |
pro->current_packet_time = get_microseconds(); |
392 |
|
393 |
rohc_debugf(2,"(iponly_decode) nbo = %d rnd = %d\n", last1->nbo, last1->rnd); |
394 |
if (pro->multiple_ip){ |
395 |
rohc_debugf(2,"Multiple ip-header\n"); |
396 |
rohc_debugf(2,"(iponly_decode) nbo2 = %d rnd2 = %d\n", last2->nbo, last2->rnd); |
397 |
} |
398 |
if (memcmp(active1, last1, sizeof(struct s_iponly_change)) != 0) { |
399 |
rohc_debugf(0,"(iponly_decode) last1 and active1 struct is not synchronized\n"); |
400 |
p = (unsigned char *)last1; |
401 |
for (i = 0; i < sizeof(struct s_iponly_change); i++) { |
402 |
rohc_debugf(1, "%2x ", p[i]); |
403 |
} |
404 |
rohc_debugf(1, "\nvs\n"); |
405 |
p = (unsigned char *)active1; |
406 |
for (i = 0; i < sizeof(struct s_iponly_change); i++) { |
407 |
rohc_debugf(1, "%2x ", p[i]); |
408 |
} |
409 |
rohc_debugf(1,"\n"); |
410 |
} |
411 |
if (memcmp(active2, last2, sizeof(struct s_iponly_change)) != 0) { |
412 |
rohc_debugf(0,"(iponly_decode) last2 and active2 struct is not synchronized\n"); |
413 |
p = (unsigned char *)last2; |
414 |
for (i = 0; i < sizeof(struct s_iponly_change); i++) { |
415 |
rohc_debugf(1,"%2x ", p[i]); |
416 |
} |
417 |
rohc_debugf(1,"\nvs\n"); |
418 |
p = (unsigned char *)active2; |
419 |
for (i = 0; i < sizeof(struct s_iponly_change); i++) { |
420 |
rohc_debugf(1,"%2x ", p[i]); |
421 |
} |
422 |
rohc_debugf(1,"\n"); |
423 |
} |
424 |
// ---- DEBUG ---- |
425 |
|
426 |
if (context->state == ROHC_NO_CONTEXT) return ROHC_ERROR; |
427 |
|
428 |
switch(package_type(src)) { |
429 |
case PACKAGE_UO_0: |
430 |
pro->package_type = PACKAGE_UO_0; |
431 |
if (context->state == ROHC_STATIC_CONTEXT) return ROHC_ERROR; |
432 |
return decode_uo0(state, context, src, src + second_byte, |
433 |
dest, size - second_byte); |
434 |
case PACKAGE_UO_1: |
435 |
pro->package_type = PACKAGE_UO_1; |
436 |
if (context->state == ROHC_STATIC_CONTEXT) return ROHC_ERROR; |
437 |
return decode_uo1(state, context, src, src + second_byte, |
438 |
dest, size - second_byte); |
439 |
case PACKAGE_UOR_2: |
440 |
pro->package_type = PACKAGE_UOR_2; |
441 |
return decode_uor2(state, context, src, src + second_byte, |
442 |
dest, size - second_byte); |
443 |
case PACKAGE_IR_DYN: |
444 |
return decode_irdyn(state, context, src, src + second_byte, |
445 |
dest, size - second_byte); |
446 |
default: |
447 |
rohc_debugf(0,"(Ip-only) Unknown package.\n"); |
448 |
return ROHC_ERROR; |
449 |
} |
450 |
} |
451 |
|
452 |
static int iponly_get_sn(struct sd_context * context) |
453 |
{ |
454 |
struct s_iponly_profile_data * pro = context->data; |
455 |
return d_get_lsb_ref(&pro->sn); |
456 |
} |
457 |
|
458 |
static struct s_profile d_ip_profile = {4, "1.0", "IP / Decompressor", |
459 |
iponly_decode, |
460 |
iponly_decode_ir, |
461 |
iponly_allocate_decode_data, |
462 |
iponly_free_decode_data, |
463 |
iponly_detect_ir_size, |
464 |
iponly_detect_ir_dyn_size, |
465 |
iponly_get_sn |
466 |
}; |
467 |
|
468 |
struct s_profile * iponly_profile_create() |
469 |
{ |
470 |
return &d_ip_profile; |
471 |
} |
472 |
|
473 |
// --------------------------------------------------------- Package type decoder |
474 |
|
475 |
/* Decode a UO-0 package */ |
476 |
static int decode_uo0( |
477 |
struct sd_rohc * state, |
478 |
struct sd_context * context, |
479 |
unsigned char * head, |
480 |
unsigned char * src, |
481 |
unsigned char * dest, |
482 |
int payload_size |
483 |
) |
484 |
{ |
485 |
unsigned char *saved_src = src; |
486 |
struct s_iponly_profile_data * pro = context->data; |
487 |
int multiple_ip = pro->multiple_ip; |
488 |
int id, id2=-1, sn, sn_bits = GET_BIT_3_6(head), sn_size = 4; |
489 |
int calc_crc, real_crc = GET_BIT_0_2(head); |
490 |
int extra_fields = 0, org_payload_size = payload_size; |
491 |
// Do the decoding / find ip-id |
492 |
extra_fields = help_to_decode_uo0_and_uo1(context, src, dest, &payload_size, sn_bits, sn_size , &id, 0 , &id2, &sn, &calc_crc); |
493 |
|
494 |
if (calc_crc != real_crc) { |
495 |
rohc_debugf(0,"UO-0: CRC failure (calc) %x vs %x (real)\n", |
496 |
calc_crc, real_crc); |
497 |
|
498 |
payload_size = org_payload_size; |
499 |
act_on_crc_failure(0,context, src, dest, sn_size, &sn, sn_bits, &payload_size, &id, 0, &id2, &calc_crc, &real_crc, 0); |
500 |
return ROHC_ERROR_CRC; |
501 |
} |
502 |
|
503 |
// if any crc-correction then three correct packet need to pass crc |
504 |
if(pro->counter){ |
505 |
if(pro->counter==1){ |
506 |
|
507 |
rohc_debugf(2,"Throw away packet, just 2 packages right so far\n"); |
508 |
|
509 |
pro->counter++; |
510 |
|
511 |
// Update the inter-packet variable |
512 |
update_inter_packet(pro); |
513 |
syncronize(pro); |
514 |
|
515 |
d_lsb_sync_ref(&pro->sn); |
516 |
d_lsb_update(&pro->sn, sn); |
517 |
d_ip_id_update(&pro->ip_id1, id, sn); |
518 |
if (pro->multiple_ip) |
519 |
d_ip_id_update(&pro->ip_id2, id2, sn); |
520 |
|
521 |
return ROHC_ERROR_CRC; |
522 |
|
523 |
}else if(pro->counter==2){ |
524 |
pro->counter = 0; |
525 |
rohc_debugf(2,"The rapair is deemed successful\n"); |
526 |
}else{ |
527 |
rohc_debugf(2,"XX Should not happen XX\n"); |
528 |
} |
529 |
} |
530 |
|
531 |
src += extra_fields; |
532 |
|
533 |
// Update the inter-packet variable |
534 |
update_inter_packet(pro); |
535 |
syncronize(pro); |
536 |
|
537 |
// Update lsb and id structs on CRC-success |
538 |
d_lsb_sync_ref(&pro->sn); |
539 |
d_lsb_update(&pro->sn, sn); |
540 |
d_ip_id_update(&pro->ip_id1, id, sn); |
541 |
if (pro->multiple_ip){ |
542 |
d_ip_id_update(&pro->ip_id2, id2, sn); |
543 |
dest += sizeof(struct iphdr); |
544 |
} |
545 |
|
546 |
// Payload |
547 |
dest += sizeof(struct iphdr); |
548 |
memcpy(dest, src, payload_size); |
549 |
|
550 |
// Statistics: |
551 |
context->header_compressed_size += src - saved_src; |
552 |
c_add_wlsb(context->header_16_compressed, 0,0, src - saved_src); |
553 |
context->header_uncompressed_size += (multiple_ip+1)*sizeof(struct iphdr); |
554 |
c_add_wlsb(context->header_16_uncompressed, 0, 0, (multiple_ip+1)*sizeof(struct iphdr)); |
555 |
|
556 |
return payload_size + (multiple_ip + 1) * sizeof(struct iphdr); |
557 |
} |
558 |
|
559 |
|
560 |
|
561 |
/* Decode a UO-1 package */ |
562 |
static int decode_uo1( |
563 |
struct sd_rohc * state, |
564 |
struct sd_context * context, |
565 |
unsigned char * head, |
566 |
unsigned char * src, |
567 |
unsigned char * dest, |
568 |
int payload_size |
569 |
) |
570 |
{ |
571 |
unsigned char *saved_src = src; |
572 |
struct s_iponly_profile_data * pro = context->data; |
573 |
|
574 |
int id = GET_BIT_0_5(head), id2=-1; |
575 |
int sn, sn_bits = GET_BIT_3_7(src), sn_size = 5; |
576 |
int org_payload_size, extra_fields=0; |
577 |
int calc_crc, real_crc = GET_BIT_0_2(src); |
578 |
src++; payload_size--; |
579 |
org_payload_size = payload_size; |
580 |
|
581 |
// Decode the id and sn |
582 |
extra_fields = help_to_decode_uo0_and_uo1(context, src, dest, &payload_size, sn_bits, sn_size , &id, 6 , &id2, &sn, &calc_crc); |
583 |
|
584 |
if (calc_crc != real_crc) { |
585 |
rohc_debugf(0,"UO-1: CRC failure (calc) %x vs %x (real)\n", |
586 |
calc_crc, real_crc); |
587 |
payload_size = org_payload_size; |
588 |
act_on_crc_failure(0,context, src, dest, sn_size, &sn, sn_bits, &payload_size, &id, 6, &id2, &calc_crc, &real_crc, 0); |
589 |
return ROHC_ERROR_CRC; |
590 |
} |
591 |
|
592 |
if(pro->counter){ |
593 |
if(pro->counter==1){ |
594 |
|
595 |
rohc_debugf(2,"Throw away packet, just 2 packages right so far\n"); |
596 |
|
597 |
pro->counter++; |
598 |
// Update the inter-packet variable |
599 |
|
600 |
update_inter_packet(pro); |
601 |
syncronize(pro); |
602 |
|
603 |
d_lsb_sync_ref(&pro->sn); |
604 |
d_lsb_update(&pro->sn, sn); |
605 |
d_ip_id_update(&pro->ip_id1, id, sn); |
606 |
if (pro->multiple_ip) |
607 |
d_ip_id_update(&pro->ip_id2, id2, sn); |
608 |
|
609 |
return ROHC_ERROR_CRC; |
610 |
|
611 |
}else if(pro->counter==2){ |
612 |
pro->counter = 0; |
613 |
rohc_debugf(2,"The rapair is deemed successful\n"); |
614 |
}else{ |
615 |
rohc_debugf(2,"XX Should not happen XX\n"); |
616 |
} |
617 |
} |
618 |
|
619 |
src += extra_fields; |
620 |
|
621 |
// Update the inter-packet variable |
622 |
update_inter_packet(pro); |
623 |
|
624 |
syncronize(pro); |
625 |
|
626 |
d_lsb_sync_ref(&pro->sn); |
627 |
d_lsb_update(&pro->sn, sn); |
628 |
d_ip_id_update(&pro->ip_id1, id, sn); |
629 |
if (pro->multiple_ip){ |
630 |
d_ip_id_update(&pro->ip_id2, id2, sn); |
631 |
dest += sizeof(struct iphdr); |
632 |
} |
633 |
|
634 |
// Payload |
635 |
dest += sizeof(struct iphdr); |
636 |
memcpy(dest, src, payload_size); |
637 |
|
638 |
// Statistics: |
639 |
context->header_compressed_size += src - saved_src; |
640 |
c_add_wlsb(context->header_16_compressed, 0,0, src - saved_src); |
641 |
context->header_uncompressed_size += (pro->multiple_ip+1)*sizeof(struct iphdr); |
642 |
c_add_wlsb(context->header_16_uncompressed, 0, 0, (pro->multiple_ip+1)*sizeof(struct iphdr)); |
643 |
|
644 |
return payload_size + (pro->multiple_ip + 1) * sizeof(struct iphdr); |
645 |
} |
646 |
|
647 |
|
648 |
/* Decode a UO-2 package */ |
649 |
static int decode_uor2( |
650 |
struct sd_rohc * state, |
651 |
struct sd_context * context, |
652 |
unsigned char * head, |
653 |
unsigned char * src, |
654 |
unsigned char * dest, |
655 |
int payload_size |
656 |
) |
657 |
{ |
658 |
unsigned char *saved_src = src; |
659 |
struct s_iponly_profile_data * pro = context->data; |
660 |
|
661 |
int org_payload_size = payload_size, extra_fields = 0; |
662 |
int sn_size = 0; |
663 |
int id = 0, id2 = 0, multiple_id = pro->multiple_ip; |
664 |
int calc_crc = 0; |
665 |
int sn_bits = GET_BIT_0_4(head) , sn = 0; |
666 |
int real_crc = GET_BIT_0_6(src); |
667 |
int ext = GET_BIT_7(src); |
668 |
src++; |
669 |
|
670 |
// Decode |
671 |
extra_fields = help_to_decode_uor2(state, context, src, dest, &payload_size, &id, &id2, &sn, &sn_size, sn_bits, ext, &calc_crc); |
672 |
|
673 |
if (calc_crc != real_crc) { |
674 |
rohc_debugf(0,"UOR-2: CRC failure (calc) %x vs %x (real)\n", |
675 |
calc_crc, real_crc); |
676 |
payload_size = org_payload_size; |
677 |
id =0 ; id2 = 0; calc_crc = 0; |
678 |
act_on_crc_failure(state, context, src, dest, sn_size, &sn, sn_bits, &payload_size, &id, 0, &id2, &calc_crc, &real_crc, ext); |
679 |
return ROHC_ERROR_CRC; |
680 |
} |
681 |
|
682 |
if(pro->counter){ |
683 |
if(pro->counter==1){ |
684 |
|
685 |
rohc_debugf(2,"Throw away packet, just 2 packages right so far\n"); |
686 |
|
687 |
pro->counter++; |
688 |
// Update the inter-packet variable |
689 |
|
690 |
update_inter_packet(pro); |
691 |
syncronize(pro); |
692 |
|
693 |
d_lsb_sync_ref(&pro->sn); |
694 |
d_lsb_update(&pro->sn, sn); |
695 |
d_ip_id_update(&pro->ip_id1, id, sn); |
696 |
if (pro->multiple_ip) |
697 |
d_ip_id_update(&pro->ip_id2, id2, sn); |
698 |
|
699 |
return ROHC_ERROR_CRC; |
700 |
|
701 |
}else if(pro->counter==2){ |
702 |
pro->counter = 0; |
703 |
rohc_debugf(2,"The rapair is deemed successful\n"); |
704 |
}else{ |
705 |
rohc_debugf(2,"XX Should not happen XX\n"); |
706 |
} |
707 |
} |
708 |
|
709 |
context->state = ROHC_FULL_CONTEXT; |
710 |
|
711 |
src += extra_fields; |
712 |
|
713 |
// if crc success |
714 |
syncronize(pro); |
715 |
|
716 |
// Update the inter-packet variable |
717 |
update_inter_packet(pro); |
718 |
|
719 |
// Update |
720 |
d_lsb_sync_ref(&pro->sn); |
721 |
d_lsb_update(&pro->sn, sn); |
722 |
d_ip_id_update(&pro->ip_id1, id, sn); |
723 |
if (pro->multiple_ip){ |
724 |
d_ip_id_update(&pro->ip_id2, id2, sn); |
725 |
dest += sizeof(struct iphdr); |
726 |
rohc_debugf(2,"Decomps reference ID2 = %d SN = %d\n",pro->ip_id2.id_ref,pro->ip_id2.sn_ref ); |
727 |
} |
728 |
// Payload |
729 |
dest += sizeof(struct iphdr); |
730 |
memcpy(dest, src, payload_size); |
731 |
rohc_debugf(2,"Decomps reference ID1 = %d SN = %d\n",pro->ip_id1.id_ref,pro->ip_id1.sn_ref ); |
732 |
rohc_debugf(2,"Decomps reference SN = %d\n",d_get_lsb_ref(&pro->sn)); |
733 |
|
734 |
// Statistics: |
735 |
context->header_compressed_size += src - saved_src; |
736 |
c_add_wlsb(context->header_16_compressed, 0,0, src - saved_src); |
737 |
context->header_uncompressed_size += (multiple_id+1)*sizeof(struct iphdr); |
738 |
c_add_wlsb(context->header_16_uncompressed, 0, 0, (multiple_id+1)*sizeof(struct iphdr)); |
739 |
|
740 |
return payload_size + (multiple_id +1) *sizeof(struct iphdr); |
741 |
|
742 |
} |
743 |
|
744 |
|
745 |
/* Decode a IR-Dyn package */ |
746 |
static int decode_irdyn( |
747 |
struct sd_rohc * state, |
748 |
struct sd_context * context, |
749 |
unsigned char * head, |
750 |
unsigned char * src2, |
751 |
unsigned char * dest, |
752 |
int payload_size |
753 |
) |
754 |
{ |
755 |
unsigned char *saved_src = src2; |
756 |
struct s_iponly_profile_data * pro = context->data; |
757 |
//struct s_iponly_change * last1 = pro->last1; |
758 |
struct s_iponly_change * active1 = pro->active1; |
759 |
struct s_iponly_change * active2 = pro->active2; |
760 |
int sn = 0, size = d_decode_dynamic_ip4(src2, &active1->ip, &active1->rnd, &active1->nbo); |
761 |
src2 += size; payload_size -= size + 2; |
762 |
|
763 |
if( pro->multiple_ip ){ |
764 |
size = d_decode_dynamic_ip4(src2, &active2->ip, &active2->rnd, &active2->nbo); |
765 |
src2 += size; payload_size -= size; |
766 |
} |
767 |
sn = ntohs(* ((__u16 *)src2)); |
768 |
d_lsb_init(&pro->sn, sn, -1); |
769 |
d_ip_id_init(&pro->ip_id1,ntohs(active1->ip.id), sn); |
770 |
syncronize(pro); |
771 |
// reset the correction-counter |
772 |
pro->counter = 0; |
773 |
src2 += 2; |
774 |
|
775 |
if (pro->multiple_ip){ |
776 |
d_ip_id_init(&pro->ip_id2,ntohs(active2->ip.id), sn); |
777 |
rohc_debugf(2,"Decomps reference ID2 = %d SN = %d\n",pro->ip_id2.id_ref,pro->ip_id2.sn_ref ); |
778 |
write_uncompressed_ip4(active1, ntohs(active1->ip.id), dest, payload_size+sizeof(struct iphdr)); |
779 |
dest += sizeof(struct iphdr); |
780 |
write_uncompressed_ip4(active2, ntohs(active2->ip.id), dest, payload_size); |
781 |
}else{ |
782 |
write_uncompressed_ip4(active1, ntohs(active1->ip.id), dest, payload_size); |
783 |
} |
784 |
context->state = ROHC_FULL_CONTEXT; |
785 |
// Update the inter-packet variable |
786 |
update_inter_packet(pro); |
787 |
|
788 |
dest += sizeof(struct iphdr); |
789 |
memcpy(dest, src2, payload_size); |
790 |
rohc_debugf(2,"Decomps reference ID = %d SN = %d\n",pro->ip_id1.id_ref,pro->ip_id1.sn_ref ); |
791 |
rohc_debugf(2,"Decomps reference SN = %d\n",d_get_lsb_ref(&pro->sn)); |
792 |
|
793 |
// Statistics: |
794 |
context->header_compressed_size += src2 - saved_src; |
795 |
c_add_wlsb(context->header_16_compressed, 0,0, src2 - saved_src); |
796 |
context->header_uncompressed_size += (pro->multiple_ip+1)*sizeof(struct iphdr); |
797 |
c_add_wlsb(context->header_16_uncompressed, 0, 0, (pro->multiple_ip+1)*sizeof(struct iphdr)); |
798 |
|
799 |
return payload_size + ((pro->multiple_ip)+1) * sizeof(struct iphdr); |
800 |
} |
801 |
|
802 |
/* a help function that does the decoding of uo0 and uo1 packets */ |
803 |
static int help_to_decode_uo0_and_uo1( |
804 |
struct sd_context * context, |
805 |
unsigned char * src, |
806 |
unsigned char * dest, |
807 |
int * payload_size, |
808 |
int sn_bits, |
809 |
int number_of_sn_bits, |
810 |
int * id, |
811 |
int number_of_id_bits, |
812 |
int * id2, |
813 |
int * sn, |
814 |
int * calc_crc |
815 |
) |
816 |
{ |
817 |
struct s_iponly_profile_data * pro = context->data; |
818 |
struct s_iponly_change * active1 = pro->active1; |
819 |
struct s_iponly_change * active2 = pro->active2; |
820 |
int field_counter = 0; |
821 |
|
822 |
*sn = d_lsb_decode(&pro->sn, sn_bits, number_of_sn_bits); |
823 |
|
824 |
if (active1->rnd) { |
825 |
*id = ntohs(*((__u16 *)src)); |
826 |
src += 2; field_counter +=2; *payload_size -= 2; |
827 |
|
828 |
} else { |
829 |
if(number_of_id_bits) |
830 |
*id = d_ip_id_decode(&pro->ip_id1, *id, number_of_id_bits, *sn); |
831 |
else |
832 |
*id = d_ip_id_decode(&pro->ip_id1, 0, 0, *sn); |
833 |
} |
834 |
|
835 |
// If multiple ip header |
836 |
if (pro->multiple_ip){ |
837 |
|
838 |
if (active2->rnd) { |
839 |
*id2 = ntohs(*((__u16 *)src)); |
840 |
|
841 |
src +=2; field_counter +=2; *payload_size -= 2; |
842 |
} else { |
843 |
*id2 = d_ip_id_decode(&pro->ip_id2, 0, 0, *sn); |
844 |
} |
845 |
} |
846 |
|
847 |
// Header write |
848 |
if (pro->multiple_ip){ |
849 |
write_uncompressed_ip4(active1, *id, dest, *payload_size+sizeof(struct iphdr)); |
850 |
write_uncompressed_ip4(active2, *id2, dest+sizeof(struct iphdr),*payload_size); |
851 |
|
852 |
}else{ |
853 |
write_uncompressed_ip4(active1, *id, dest, *payload_size); |
854 |
} |
855 |
|
856 |
// Check CRC |
857 |
*calc_crc = crc_calculate(CRC_TYPE_3, dest, (pro->multiple_ip + 1) * sizeof(struct iphdr)); |
858 |
|
859 |
return field_counter; |
860 |
} |
861 |
|
862 |
/* a function that does the decoding of uor2 packets */ |
863 |
static int help_to_decode_uor2( |
864 |
struct sd_rohc * state, |
865 |
struct sd_context * context, |
866 |
unsigned char * src2, |
867 |
unsigned char * dest, |
868 |
int * payload_size, |
869 |
int * id, |
870 |
int * id2, |
871 |
int * sn, |
872 |
int * sn_size, |
873 |
int sn_bits, |
874 |
int ext, |
875 |
int * calc_crc |
876 |
) |
877 |
{ |
878 |
struct s_iponly_profile_data * pro = context->data; |
879 |
struct s_iponly_change * active1 = pro->active1; |
880 |
struct s_iponly_change * active2 = pro->active2; |
881 |
int id2_updated = 0, size = 0; |
882 |
int no_ip_id_update = 0; |
883 |
int field_counter = 0; |
884 |
|
885 |
*sn = sn_bits; |
886 |
|
887 |
if (ext) { |
888 |
// decode extention |
889 |
switch(extention_type(src2)) { |
890 |
case PACKAGE_EXT_0: |
891 |
size = decode_extention0(src2, sn, id); |
892 |
// ip_id_bits == 3 |
893 |
*sn_size = 8; |
894 |
*sn = d_lsb_decode(&pro->sn, *sn, *sn_size ); |
895 |
*id = d_ip_id_decode(&pro->ip_id1, *id, 3, *sn); |
896 |
*id2 = d_ip_id_decode(&pro->ip_id2, 0, 0, *sn); |
897 |
break; |
898 |
|
899 |
case PACKAGE_EXT_1: |
900 |
size = decode_extention1(src2, sn, id); |
901 |
// ip_id bits == 11 |
902 |
*sn_size = 8; |
903 |
*sn = d_lsb_decode(&pro->sn, *sn, *sn_size ); |
904 |
*id = d_ip_id_decode(&pro->ip_id1, *id, 11, *sn); |
905 |
*id2 = d_ip_id_decode(&pro->ip_id2, 0, 0, *sn); |
906 |
break; |
907 |
|
908 |
case PACKAGE_EXT_2: |
909 |
size = decode_extention2(src2, sn, id, id2); |
910 |
// ip_id bits == 8 |
911 |
*sn_size = 8; |
912 |
*sn = d_lsb_decode(&pro->sn, *sn, *sn_size ); |
913 |
*id2 = d_ip_id_decode(&pro->ip_id1, *id, 8, *sn);//inner |
914 |
*id = d_ip_id_decode(&pro->ip_id2, *id2, 11, *sn);//outer |
915 |
break; |
916 |
|
917 |
case PACKAGE_EXT_3: |
918 |
*sn_size = 5; |
919 |
size = decode_extention3(src2, context, state, sn, |
920 |
sn_size, &no_ip_id_update, &id2_updated); |
921 |
|
922 |
rohc_debugf(2,"(iponly_decode) after ext 3 : nbo = %d rnd = %d\n", active1->nbo, active1->rnd); |
923 |
|
924 |
*sn = d_lsb_decode(&pro->sn, *sn, *sn_size ); |
925 |
|
926 |
if (no_ip_id_update) { |
927 |
*id = ntohs(active1->ip.id); |
928 |
} else { |
929 |
*id = d_ip_id_decode(&pro->ip_id1, 0, 0, *sn); |
930 |
} |
931 |
if( pro->multiple_ip ){ |
932 |
rohc_debugf(2,"(iponly_decode) after ext 3 : nbo2 = %d rnd2 = %d\n", active2->nbo, active2->rnd); |
933 |
|
934 |
if (id2_updated){ |
935 |
*id2 = ntohs(active2->ip.id); |
936 |
}else |
937 |
*id2 = d_ip_id_decode(&pro->ip_id2, 0, 0, *sn); |
938 |
|
939 |
} |
940 |
break; |
941 |
} |
942 |
|
943 |
|
944 |
src2 += size; |
945 |
field_counter +=size; |
946 |
*payload_size -= size + 1; |
947 |
} else { |
948 |
// No extention |
949 |
*sn_size = 5; |
950 |
*sn = d_lsb_decode(&pro->sn, *sn , *sn_size); |
951 |
|
952 |
*id = d_ip_id_decode(&pro->ip_id1, 0, 0, *sn); |
953 |
if( pro->multiple_ip) |
954 |
*id2 = d_ip_id_decode(&pro->ip_id1, 0, 0, *sn); |
955 |
*payload_size -= 1; |
956 |
} |
957 |
|
958 |
|
959 |
// Random IP ID ? |
960 |
if (active1->rnd) { |
961 |
*id = ntohs(*((__u16 *)src2)); |
962 |
src2 +=2; field_counter +=2; *payload_size -= 2; |
963 |
} |
964 |
|
965 |
// Multiple ip-header |
966 |
|
967 |
if (( pro->multiple_ip )&&( active2->rnd )){ |
968 |
*id2 = ntohs(*((__u16 *)src2)); |
969 |
src2 +=2; field_counter +=2; *payload_size -= 2; |
970 |
} |
971 |
|
972 |
|
973 |
// Header write |
974 |
if (pro->multiple_ip){ |
975 |
write_uncompressed_ip4(active1, *id, dest, *payload_size+sizeof(struct iphdr)); |
976 |
write_uncompressed_ip4(active2, *id2, dest+sizeof(struct iphdr),*payload_size); |
977 |
}else{ |
978 |
write_uncompressed_ip4(active1, *id, dest, *payload_size); |
979 |
} |
980 |
|
981 |
// CRC-check |
982 |
*calc_crc = crc_calculate(CRC_TYPE_7, dest, (pro->multiple_ip + 1) * sizeof(struct iphdr)); |
983 |
|
984 |
return field_counter; |
985 |
} |
986 |
|
987 |
|
988 |
|
989 |
|
990 |
|
991 |
// --------------------------------------------------------- |
992 |
|
993 |
/* Decode extention 0. |
994 |
* - SN value is expanded with 3 lower bits |
995 |
* - IP-ID is replaced with 3 bits |
996 |
*/ |
997 |
static int decode_extention0(unsigned char * src, int * sn, int * ip_id) |
998 |
{ |
999 |
*sn = *sn << 3 | GET_BIT_3_5(src); |
1000 |
*ip_id = GET_BIT_0_2(src); |
1001 |
return 1; |
1002 |
} |
1003 |
|
1004 |
/* Decode extention 1 |
1005 |
* - SN value is expanded with 3 lower bits |
1006 |
* - IP-ID is replaced with 11 bits |
1007 |
*/ |
1008 |
static int decode_extention1(unsigned char * src, int * sn, int * ip_id) |
1009 |
{ |
1010 |
*sn = *sn << 3 | GET_BIT_3_5(src); |
1011 |
*ip_id = GET_BIT_0_2(src); |
1012 |
|
1013 |
src++; |
1014 |
*ip_id = *ip_id << 8 | *src; |
1015 |
|
1016 |
return 2; |
1017 |
} |
1018 |
|
1019 |
/* Decode extention 2 |
1020 |
* - SN value is expanded with 3 lower bits |
1021 |
* - IP-ID is replaced with 8 bits |
1022 |
*/ |
1023 |
static int decode_extention2(unsigned char * src, int * sn, int * ip_id, int * ip_id2) |
1024 |
{ |
1025 |
|
1026 |
*sn = *sn << 3 | GET_BIT_3_5(src); |
1027 |
*ip_id2 = GET_BIT_0_2(src); |
1028 |
src++; |
1029 |
|
1030 |
*ip_id2 = *ip_id2 << 8 | *src; |
1031 |
src++; |
1032 |
|
1033 |
*ip_id = *src; |
1034 |
return 3; |
1035 |
} |
1036 |
|
1037 |
/* Decode extention 3 |
1038 |
* - Updates random fields in the s_iponly_change |
1039 |
* - May update the SN value with 8 lower bits. sn_size is then changed |
1040 |
*/ |
1041 |
static int decode_extention3( |
1042 |
unsigned char * src, |
1043 |
struct sd_context * context, |
1044 |
struct sd_rohc * state, |
1045 |
int * sn, |
1046 |
int * sn_size, |
1047 |
int * ip_id_changed, |
1048 |
int * update_id2 |
1049 |
) |
1050 |
{ |
1051 |
struct s_iponly_profile_data * pro = context->data; |
1052 |
struct s_iponly_change * active1 = pro->active1; |
1053 |
struct s_iponly_change * active2 = pro->active2; |
1054 |
unsigned char * org = src; |
1055 |
unsigned char * fields = src + 1; |
1056 |
int S = GET_BIT_5(src); |
1057 |
int mode = GET_BIT_3_4(src); |
1058 |
int I = GET_BIT_2(src); |
1059 |
int ip = GET_BIT_1(src); |
1060 |
int ip2 = GET_BIT_0(src); |
1061 |
int size; |
1062 |
|
1063 |
src++; |
1064 |
|
1065 |
if (ip) fields++; |
1066 |
if (ip2) fields++; |
1067 |
|
1068 |
if (S) { |
1069 |
*sn = (*sn << 8) + *fields; |
1070 |
*sn_size += 8; |
1071 |
fields++; |
1072 |
} |
1073 |
|
1074 |
if (ip) { |
1075 |
if(pro->multiple_ip){ |
1076 |
size = decode_inner_header_flags(src, fields, &active2->ip, |
1077 |
&active2->rnd, &active2->nbo); |
1078 |
}else |
1079 |
size = decode_inner_header_flags(src, fields, &active1->ip, |
1080 |
&active1->rnd, &active1->nbo); |
1081 |
fields += size; |
1082 |
} |
1083 |
if (I) { |
1084 |
if(pro->multiple_ip){ |
1085 |
active2->ip.id = *((__u16 *)fields); |
1086 |
fields += 2; |
1087 |
*update_id2 = 1; |
1088 |
}else{ |
1089 |
active1->ip.id = *((__u16 *)fields); |
1090 |
fields += 2; |
1091 |
*ip_id_changed = 1; |
1092 |
} |
1093 |
} |
1094 |
if (ip2) { |
1095 |
size = decode_outer_header_flags(src, fields, &active1->ip, |
1096 |
&active1->rnd, &active1->nbo, ip_id_changed); |
1097 |
fields += size; |
1098 |
} |
1099 |
|
1100 |
if(mode != context->mode){ |
1101 |
rohc_debugf(2,"mode is not equal on decomp and comp.\n"); |
1102 |
d_change_mode_feedback(state, context); |
1103 |
} |
1104 |
return fields - org; |
1105 |
} |
1106 |
|
1107 |
// --------------------------------------------------------- Local utils functions |
1108 |
|
1109 |
// Deceide what package type |
1110 |
static int package_type(const unsigned char * p) |
1111 |
{ |
1112 |
if (!GET_BIT_7(p)) { |
1113 |
return PACKAGE_UO_0; |
1114 |
} else if (!GET_BIT_6(p)) { |
1115 |
return PACKAGE_UO_1; |
1116 |
} else if (GET_BIT_5_7(p) == 6) { |
1117 |
return PACKAGE_UOR_2; |
1118 |
} else if (*p == 0xf8) { |
1119 |
return PACKAGE_IR_DYN; |
1120 |
} else if ( (*p & 0xfe) == 0xfc) { |
1121 |
return PACKAGE_IR; |
1122 |
} else { |
1123 |
return PACKAGE_UNKNOWN; |
1124 |
} |
1125 |
} |
1126 |
|
1127 |
// Copy the active-structs to last-structs. |
1128 |
static void syncronize(struct s_iponly_profile_data * pro) |
1129 |
{ |
1130 |
memcpy(pro->last1, pro->active1, sizeof(struct s_iponly_change)); |
1131 |
memcpy(pro->last2, pro->active2, sizeof(struct s_iponly_change)); |
1132 |
} |
1133 |
|
1134 |
// Copy the last-structs to the active-structs. |
1135 |
static void sync_on_failure(struct s_iponly_profile_data * pro) |
1136 |
{ |
1137 |
memcpy(pro->active1, pro->last1, sizeof(struct s_iponly_change)); |
1138 |
memcpy(pro->active2, pro->last2, sizeof(struct s_iponly_change)); |
1139 |
} |
1140 |
|
1141 |
// Deceide the extention type |
1142 |
static int extention_type(const unsigned char * p) |
1143 |
{ |
1144 |
return GET_BIT_6_7(p); |
1145 |
} |
1146 |
|
1147 |
/* Decode inner IP flags and fields. Storage the values |
1148 |
* in a IP-head struct. |
1149 |
*/ |
1150 |
static int decode_inner_header_flags( |
1151 |
unsigned char * flags, |
1152 |
unsigned char * fields, |
1153 |
struct iphdr * ip, |
1154 |
int * rnd, int * nbo) |
1155 |
{ |
1156 |
int size = 0; |
1157 |
if (GET_BIT_7(flags)) { |
1158 |
ip->tos = *fields; |
1159 |
fields++; size++; |
1160 |
} |
1161 |
if (GET_BIT_6(flags)) { |
1162 |
ip->ttl = *fields; |
1163 |
fields++; size++; |
1164 |
} |
1165 |
if (GET_BIT_5(flags)) { |
1166 |
ip->frag_off = htons(IP_DF); |
1167 |
} else { |
1168 |
ip->frag_off = 0; |
1169 |
} |
1170 |
if (GET_BIT_4(flags)) { |
1171 |
ip->protocol = *fields; |
1172 |
fields++; size++; |
1173 |
} |
1174 |
if (GET_BIT_3(flags)) { |
1175 |
// TODO, list compression |
1176 |
rohc_debugf(0,"Listcompression is not supported\n"); |
1177 |
} |
1178 |
*nbo = GET_BIT_2(flags); |
1179 |
*rnd = GET_BIT_1(flags); |
1180 |
return size; |
1181 |
} |
1182 |
|
1183 |
/* Decode outer IP flags and fields. Storage the values |
1184 |
* in a IP-head struct. |
1185 |
*/ |
1186 |
static int decode_outer_header_flags( |
1187 |
unsigned char * flags, |
1188 |
unsigned char * fields, |
1189 |
struct iphdr * ip, |
1190 |
int * rnd, int * nbo, |
1191 |
int * updated_id) |
1192 |
{ |
1193 |
int size = 0; |
1194 |
if (GET_BIT_7(flags)) { |
1195 |
ip->tos = *fields; |
1196 |
fields++; size++; |
1197 |
} |
1198 |
if (GET_BIT_6(flags)) { |
1199 |
ip->ttl = *fields; |
1200 |
fields++; size++; |
1201 |
} |
1202 |
if (GET_BIT_5(flags)) { |
1203 |
ip->frag_off = htons(IP_DF); |
1204 |
} else { |
1205 |
ip->frag_off = 0; |
1206 |
} |
1207 |
if (GET_BIT_4(flags)) { |
1208 |
ip->protocol = *fields; |
1209 |
fields++; size++; |
1210 |
} |
1211 |
if (GET_BIT_3(flags)) { |
1212 |
// TODO, list compression |
1213 |
rohc_debugf(0,"Listcompression is not supported\n"); |
1214 |
} |
1215 |
*nbo = GET_BIT_2(flags); |
1216 |
*rnd = GET_BIT_1(flags); |
1217 |
|
1218 |
if (GET_BIT_0(flags)) { |
1219 |
ip->id = *((__u16 *)fields); |
1220 |
fields += 2; size += 2; |
1221 |
*updated_id = 1; |
1222 |
} |
1223 |
return size; |
1224 |
} |
1225 |
|
1226 |
/* Write a uncompressed IP v4 header */ |
1227 |
static void write_uncompressed_ip4( |
1228 |
struct s_iponly_change * active, |
1229 |
int ip_id, |
1230 |
unsigned char * dest, |
1231 |
int payload_size |
1232 |
) |
1233 |
{ |
1234 |
struct iphdr * ip = (struct iphdr *)dest; |
1235 |
|
1236 |
// --- static & some changing |
1237 |
memcpy(dest, &active->ip, sizeof(struct iphdr)); |
1238 |
|
1239 |
// --- ip-id |
1240 |
ip->id = htons(ip_id); |
1241 |
if (!active->nbo) ip->id = __swab16(ip->id); |
1242 |
|
1243 |
//--- Static-known fields |
1244 |
ip->ihl = 5; |
1245 |
|
1246 |
//--- Interfered fields |
1247 |
ip->tot_len = htons(payload_size + (ip->ihl * 4)); |
1248 |
ip->check = 0; |
1249 |
ip->check = ip_fast_csum(dest, ip->ihl); |
1250 |
} |
1251 |
|
1252 |
|
1253 |
|
1254 |
/* This function try to repair the SN in one of two different ways |
1255 |
* |
1256 |
*/ |
1257 |
static int act_on_crc_failure( |
1258 |
struct sd_rohc * state, |
1259 |
struct sd_context * context, |
1260 |
unsigned char * src, |
1261 |
unsigned char * dest, |
1262 |
int sn_size, |
1263 |
int * sn, |
1264 |
int sn_bits, |
1265 |
int * payload_size, |
1266 |
int * id, |
1267 |
int id_size, |
1268 |
int * id2, |
1269 |
int * calc_crc, |
1270 |
int * real_crc, |
1271 |
int ext |
1272 |
) |
1273 |
{ |
1274 |
struct s_iponly_profile_data * pro = context->data; |
1275 |
|
1276 |
int sn_ref = 0, intervall = 0; |
1277 |
int sn_curr2 = 0, sn_curr1 = 0; |
1278 |
int sn_update = 0; |
1279 |
|
1280 |
sync_on_failure(pro); |
1281 |
|
1282 |
if(CRC_ACTION){ |
1283 |
rohc_debugf(0,"Try to repair the CRC\n"); |
1284 |
|
1285 |
if(pro->last_packet_time) //if last packettime == 0 then IR was just sent and ... |
1286 |
intervall = pro->current_packet_time - pro->last_packet_time; |
1287 |
|
1288 |
if(intervall > ((1 << sn_size)*(pro->inter_arrival_time))){ |
1289 |
rohc_debugf(0,"ROHC: repair with the assumption: SN LSB wraparound\n"); |
1290 |
rohc_debugf(2,"inter_arrival_time = %d and current intervall is = %d\n", pro->inter_arrival_time, intervall); |
1291 |
rohc_debugf(2,"add %d to SN\n", 1 << sn_size); |
1292 |
|
1293 |
// Try and update the SN |
1294 |
sn_ref = d_get_lsb_ref(&pro->sn); |
1295 |
sn_ref += (1 << sn_size); |
1296 |
d_lsb_sync_ref(&pro->sn); |
1297 |
d_lsb_update(&pro->sn, sn_ref); |
1298 |
*sn = d_lsb_decode(&pro->sn, sn_bits, sn_size ); |
1299 |
|
1300 |
pro->counter = 0; |
1301 |
|
1302 |
}else{ |
1303 |
// try with the old sn_ref value |
1304 |
|
1305 |
rohc_debugf(0,"ROHC: repair with the assumption: incorrect SN-updates\n"); |
1306 |
rohc_debugf(2,"inter_arrival_time = %d and current intervall is = %d\n", pro->inter_arrival_time, intervall); |
1307 |
|
1308 |
// save current referece value |
1309 |
sn_curr1 = d_get_lsb_ref(&pro->sn); |
1310 |
// test with old reference value |
1311 |
d_lsb_update(&pro->sn, d_get_lsb_old_ref(&pro->sn)); |
1312 |
|
1313 |
sn_curr2 = d_lsb_decode(&pro->sn, sn_bits, sn_size ); |
1314 |
|
1315 |
if( sn_curr2 == *sn){ |
1316 |
rohc_debugf(2,"with old ref value we get the same sn\n"); |
1317 |
return ROHC_ERROR_CRC; |
1318 |
} |
1319 |
*sn = sn_curr2; |
1320 |
d_lsb_update(&pro->sn, sn_curr2); |
1321 |
sn_update = 1; |
1322 |
pro->counter = 0; |
1323 |
} |
1324 |
rohc_debugf(2,"Try a new decompression with another sn \n"); |
1325 |
// Try a new decompression with another SN |
1326 |
switch (pro->package_type){ |
1327 |
case PACKAGE_UO_0: |
1328 |
//fall through |
1329 |
case PACKAGE_UO_1: |
1330 |
help_to_decode_uo0_and_uo1(context, src, dest, payload_size, sn_bits, sn_size , id, id_size, id2, sn, calc_crc); |
1331 |
break; |
1332 |
case PACKAGE_UOR_2: |
1333 |
*sn = sn_bits; |
1334 |
help_to_decode_uor2(state, context, src, dest, payload_size, id, id2, sn, &sn_size, sn_bits, ext, calc_crc); |
1335 |
break; |
1336 |
default: |
1337 |
rohc_debugf(0,"(Ip-only) A existing packet?\n"); |
1338 |
d_lsb_update(&pro->sn, sn_curr1); |
1339 |
return ROHC_ERROR_CRC; |
1340 |
} |
1341 |
|
1342 |
if (*calc_crc != *real_crc){ |
1343 |
rohc_debugf(0,"ROHC: CRC failure also on the second attempt (calc) %x vs %x (real)\n",*calc_crc, *real_crc); |
1344 |
pro->counter = 0; |
1345 |
if(sn_update) |
1346 |
d_lsb_update(&pro->sn, sn_curr1); //reference curr1 should be used |
1347 |
sync_on_failure(pro); |
1348 |
return ROHC_ERROR_CRC; |
1349 |
} |
1350 |
//CRC-pass |
1351 |
rohc_debugf(2,"Update and sync with the new SN then throw away the packet\n"); |
1352 |
pro->counter++; |
1353 |
update_inter_packet(pro); |
1354 |
|
1355 |
syncronize(pro); |
1356 |
|
1357 |
if(!sn_update){ |
1358 |
d_lsb_sync_ref(&pro->sn); |
1359 |
d_lsb_update(&pro->sn, *sn); |
1360 |
}else |
1361 |
d_lsb_update(&pro->sn, sn_curr2); |
1362 |
|
1363 |
d_ip_id_update(&pro->ip_id1, *id, *sn); |
1364 |
if (pro->multiple_ip) |
1365 |
d_ip_id_update(&pro->ip_id2, *id2, *sn); |
1366 |
|
1367 |
return ROHC_ERROR_CRC; |
1368 |
|
1369 |
}else{ |
1370 |
return ROHC_ERROR_CRC; |
1371 |
} |
1372 |
} |
1373 |
|
1374 |
/* Update the inter-packet time, a sort of averange over the last inter-packet times */ |
1375 |
static void update_inter_packet(struct s_iponly_profile_data * pro) |
1376 |
{ |
1377 |
int last_time = pro->last_packet_time; |
1378 |
int delta = 0; |
1379 |
rohc_debugf(2,"current time = %d and last time = %d\n", pro->current_packet_time, last_time); |
1380 |
|
1381 |
if (last_time) |
1382 |
delta = pro->current_packet_time - last_time; |
1383 |
pro->last_packet_time = pro->current_packet_time; |
1384 |
if (pro->inter_arrival_time){ |
1385 |
pro->inter_arrival_time = (pro->inter_arrival_time >> WEIGHT_OLD) + (delta >> WEIGHT_NEW); |
1386 |
|
1387 |
} else |
1388 |
pro->inter_arrival_time = delta; |
1389 |
|
1390 |
rohc_debugf(2,"inter_arrival_time = %d and current arrival delta is = %d\n", pro->inter_arrival_time, delta); |
1391 |
} |