3214 lines
109 KiB
C
3214 lines
109 KiB
C
/* sigcomp-udvm.c
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* Routines making up the Universal Decompressor Virtual Machine (UDVM) used for
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* Signaling Compression (SigComp) dissection.
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* Copyright 2004, Anders Broman <anders.broman@ericsson.com>
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*
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* $Id$
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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* References:
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* http://www.ietf.org/rfc/rfc3320.txt?number=3320
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* http://www.ietf.org/rfc/rfc3321.txt?number=3321
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* Useful links :
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* http://www.ietf.org/internet-drafts/draft-ietf-rohc-sigcomp-impl-guide-05.txt
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* http://www.ietf.org/internet-drafts/draft-ietf-rohc-sigcomp-sip-01.txt
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*/
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#include "config.h"
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <glib.h>
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#include "packet.h"
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#include "strutil.h"
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#include "sigcomp-udvm.h"
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#include "sigcomp_state_hdlr.h"
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#include "crypt/sha1.h"
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#include "wsutil/crc16.h"
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#include "except.h"
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#define SIGCOMP_INSTR_DECOMPRESSION_FAILURE 0
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#define SIGCOMP_INSTR_AND 1
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#define SIGCOMP_INSTR_OR 2
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#define SIGCOMP_INSTR_NOT 3
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#define SIGCOMP_INSTR_LSHIFT 4
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#define SIGCOMP_INSTR_RSHIFT 5
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#define SIGCOMP_INSTR_ADD 6
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#define SIGCOMP_INSTR_SUBTRACT 7
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#define SIGCOMP_INSTR_MULTIPLY 8
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#define SIGCOMP_INSTR_DIVIDE 9
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#define SIGCOMP_INSTR_REMAINDER 10
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#define SIGCOMP_INSTR_SORT_ASCENDING 11
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#define SIGCOMP_INSTR_SORT_DESCENDING 12
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#define SIGCOMP_INSTR_SHA_1 13
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#define SIGCOMP_INSTR_LOAD 14
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#define SIGCOMP_INSTR_MULTILOAD 15
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#define SIGCOMP_INSTR_PUSH 16
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#define SIGCOMP_INSTR_POP 17
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#define SIGCOMP_INSTR_COPY 18
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#define SIGCOMP_INSTR_COPY_LITERAL 19
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#define SIGCOMP_INSTR_COPY_OFFSET 20
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#define SIGCOMP_INSTR_MEMSET 21
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#define SIGCOMP_INSTR_JUMP 22
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#define SIGCOMP_INSTR_COMPARE 23
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#define SIGCOMP_INSTR_CALL 24
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#define SIGCOMP_INSTR_RETURN 25
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#define SIGCOMP_INSTR_SWITCH 26
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#define SIGCOMP_INSTR_CRC 27
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#define SIGCOMP_INSTR_INPUT_BYTES 28
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#define SIGCOMP_INSTR_INPUT_BITS 29
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#define SIGCOMP_INSTR_INPUT_HUFFMAN 30
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#define SIGCOMP_INSTR_STATE_ACCESS 31
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#define SIGCOMP_INSTR_STATE_CREATE 32
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#define SIGCOMP_INSTR_STATE_FREE 33
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#define SIGCOMP_INSTR_OUTPUT 34
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#define SIGCOMP_INSTR_END_MESSAGE 35
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static gboolean print_level_1;
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static gboolean print_level_2;
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static gboolean print_level_3;
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static gint show_instr_detail_level;
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/* Internal result code values of decompression failures */
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const value_string result_code_vals[] = {
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{ 0, "No decompression failure" },
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{ 1, "Partial state length less than 6 or greater than 20 bytes long" },
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{ 2, "No state match" },
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{ 3, "state_begin + state_length > size of state" },
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{ 4, "Operand_2 is Zero" },
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{ 5, "Switch statement failed j >= n" },
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{ 6, "Attempt to jump outside of UDVM memory" },
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{ 7, "L in input-bits > 16" },
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{ 8, "input_bit_order > 7" },
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{ 9, "Instruction Decompression failure encountered" },
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{10, "Input huffman failed j > n" },
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{11, "Input bits requested beyond end of message" },
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{12, "more than four state creation requests are made before the END-MESSAGE instruction" },
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{13, "state_retention_priority is 65535" },
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{14, "Input bytes requested beyond end of message" },
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{15, "Maximum number of UDVM cycles reached" },
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{16, "UDVM stack underflow" },
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{ 255, "This branch isn't coded yet" },
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{ 0, NULL }
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};
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static int decode_udvm_literal_operand(guint8 *buff,guint operand_address, guint16 *value);
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static int dissect_udvm_reference_operand(guint8 *buff,guint operand_address, guint16 *value, guint *result_dest);
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static int decode_udvm_multitype_operand(guint8 *buff,guint operand_address,guint16 *value);
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static int decode_udvm_address_operand(guint8 *buff,guint operand_address, guint16 *value,guint current_address);
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static int decomp_dispatch_get_bits(tvbuff_t *message_tvb,proto_tree *udvm_tree,guint8 bit_order,
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guint8 *buff,guint16 *old_input_bit_order, guint16 *remaining_bits,
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guint16 *input_bits, guint *input_address, guint16 length, guint16 *result_code,guint msg_end);
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tvbuff_t*
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decompress_sigcomp_message(tvbuff_t *bytecode_tvb, tvbuff_t *message_tvb, packet_info *pinfo,
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proto_tree *udvm_tree, gint udvm_mem_dest,
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gint print_flags, gint hf_id,
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gint header_len,
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gint byte_code_state_len, gint byte_code_id_len,
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gint udvm_start_ip)
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{
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tvbuff_t *decomp_tvb;
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/* UDVM memory must be initialised to zero */
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guint8 *buff = ep_alloc0(UDVM_MEMORY_SIZE);
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char string[2];
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guint8 *out_buff; /* Largest allowed size for a message is UDVM_MEMORY_SIZE = 65536 */
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guint32 i = 0;
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guint16 n = 0;
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guint16 m = 0;
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guint16 x;
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guint k = 0;
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guint16 H;
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guint16 oldH;
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guint offset = 0;
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guint result_dest;
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guint code_length =0;
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guint8 current_instruction;
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guint current_address;
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guint operand_address;
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guint input_address;
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guint16 output_address = 0;
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guint next_operand_address;
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guint8 octet;
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guint8 msb;
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guint8 lsb;
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guint16 byte_copy_right;
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guint16 byte_copy_left;
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guint16 input_bit_order;
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guint16 stack_location;
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guint16 stack_fill;
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guint16 result;
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guint msg_end = tvb_reported_length_remaining(message_tvb, 0);
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guint16 result_code = 0;
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guint16 old_input_bit_order = 0;
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guint16 remaining_bits = 0;
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guint16 input_bits = 0;
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guint8 bit_order = 0;
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gboolean outside_huffman_boundaries = TRUE;
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gboolean print_in_loop = FALSE;
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guint16 instruction_address;
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guint8 no_of_state_create = 0;
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guint16 state_length_buff[5];
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guint16 state_address_buff[5];
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guint16 state_instruction_buff[5];
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guint16 state_minimum_access_length_buff[5];
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/* guint16 state_state_retention_priority_buff[5]; */
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guint32 used_udvm_cycles = 0;
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guint cycles_per_bit;
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guint maximum_UDVM_cycles;
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guint8 *sha1buff;
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unsigned char sha1_digest_buf[STATE_BUFFER_SIZE];
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sha1_context ctx;
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/* UDVM operand variables */
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guint16 length;
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guint16 at_address;
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guint16 destination;
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guint16 addr;
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guint16 value;
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guint16 p_id_start;
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guint16 p_id_length;
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guint16 state_begin;
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guint16 state_length;
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guint16 state_address;
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guint16 state_instruction;
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guint16 operand_1;
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guint16 operand_2;
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guint16 value_1;
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guint16 value_2;
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guint16 at_address_1;
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guint16 at_address_2;
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guint16 at_address_3;
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guint16 j;
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guint16 bits_n;
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guint16 lower_bound_n;
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guint16 upper_bound_n;
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guint16 uncompressed_n;
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guint16 position;
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guint16 ref_destination; /* could I have used $destination ? */
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guint16 multy_offset;
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guint16 output_start;
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guint16 output_length;
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guint16 minimum_access_length;
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guint16 state_retention_priority;
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guint16 requested_feedback_location;
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guint16 returned_parameters_location;
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guint16 start_value;
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/* Set print parameters */
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print_level_1 = FALSE;
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print_level_2 = FALSE;
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print_level_3 = FALSE;
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show_instr_detail_level = 0;
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switch( print_flags ) {
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case 0:
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break;
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case 1:
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print_level_1 = TRUE;
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show_instr_detail_level = 1;
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break;
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case 2:
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print_level_1 = TRUE;
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print_level_2 = TRUE;
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show_instr_detail_level = 1;
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break;
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case 3:
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print_level_1 = TRUE;
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print_level_2 = TRUE;
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print_level_3 = TRUE;
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show_instr_detail_level = 2;
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break;
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default:
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print_level_1 = TRUE;
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show_instr_detail_level = 1;
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break;
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}
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/* Set initial UDVM data
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* The first 32 bytes of UDVM memory are then initialized to special
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* values as illustrated in Figure 5.
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*
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* 0 7 8 15
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | UDVM_memory_size | 0 - 1
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | cycles_per_bit | 2 - 3
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | SigComp_version | 4 - 5
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | partial_state_ID_length | 6 - 7
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | state_length | 8 - 9
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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* | |
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* : reserved : 10 - 31
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* | |
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* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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*
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* Figure 5: Initializing Useful Values in UDVM memory
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*/
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/* UDVM_memory_size */
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buff[0] = (UDVM_MEMORY_SIZE >> 8) & 0x00FF;
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buff[1] = UDVM_MEMORY_SIZE & 0x00FF;
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/* cycles_per_bit */
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buff[2] = 0;
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buff[3] = 16;
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/* SigComp_version */
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buff[4] = 0;
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buff[5] = 1;
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/* partial_state_ID_length */
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buff[6] = (byte_code_id_len >> 8) & 0x00FF;
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buff[7] = byte_code_id_len & 0x00FF;
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/* state_length */
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buff[8] = (byte_code_state_len >> 8) & 0x00FF;
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buff[9] = byte_code_state_len & 0x00FF;
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code_length = tvb_reported_length_remaining(bytecode_tvb, 0);
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cycles_per_bit = buff[2] << 8;
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cycles_per_bit = cycles_per_bit | buff[3];
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/*
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* maximum_UDVM_cycles = (8 * n + 1000) * cycles_per_bit
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*/
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maximum_UDVM_cycles = (( 8 * (header_len + msg_end) ) + 1000) * cycles_per_bit;
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proto_tree_add_text(udvm_tree, bytecode_tvb, offset, 1,"maximum_UDVM_cycles(%u) = (( 8 * msg_end(%u) ) + 1000) * cycles_per_bit(%u)",maximum_UDVM_cycles,msg_end,cycles_per_bit);
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proto_tree_add_text(udvm_tree, bytecode_tvb, offset, 1,"Message Length: %u,Byte code length: %u, Maximum UDVM cycles: %u",msg_end,code_length,maximum_UDVM_cycles);
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/* Load bytecode into UDVM starting at "udvm_mem_dest" */
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i = udvm_mem_dest;
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if ( print_level_3 )
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proto_tree_add_text(udvm_tree, bytecode_tvb, offset, 1,"Load bytecode into UDVM starting at %u",i);
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while ( code_length > offset && i < UDVM_MEMORY_SIZE ) {
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buff[i] = tvb_get_guint8(bytecode_tvb, offset);
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if ( print_level_3 )
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proto_tree_add_text(udvm_tree, bytecode_tvb, offset, 1,
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" Addr: %u Instruction code(0x%0x) ", i, buff[i]);
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i++;
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offset++;
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}
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/* Largest allowed size for a message is UDVM_MEMORY_SIZE = 65536 */
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out_buff = g_malloc(UDVM_MEMORY_SIZE);
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/* Start executing code */
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current_address = udvm_start_ip;
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input_address = 0;
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operand_address = 0;
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proto_tree_add_text(udvm_tree, bytecode_tvb, offset, 1,"UDVM EXECUTION STARTED at Address: %u Message size %u",
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current_address, msg_end);
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execute_next_instruction:
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if ( used_udvm_cycles > maximum_UDVM_cycles ){
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result_code = 15;
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goto decompression_failure;
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}
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used_udvm_cycles++;
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current_instruction = buff[current_address & 0xffff];
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switch ( current_instruction ) {
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case SIGCOMP_INSTR_DECOMPRESSION_FAILURE:
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if ( result_code == 0 )
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result_code = 9;
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
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"Addr: %u ## DECOMPRESSION-FAILURE(0)",
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current_address);
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Wireshark UDVM diagnostic: %s.",
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val_to_str(result_code, result_code_vals,"Unknown (%u)"));
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if ( output_address > 0 ){
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/* At least something got decompressed, show it */
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decomp_tvb = tvb_new_child_real_data(message_tvb, out_buff,output_address,output_address);
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/* Arrange that the allocated packet data copy be freed when the
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* tvbuff is freed.
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*/
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tvb_set_free_cb( decomp_tvb, g_free );
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/* Add the tvbuff to the list of tvbuffs to which the tvbuff we
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* were handed refers, so it'll get cleaned up when that tvbuff
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* is cleaned up.
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*/
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add_new_data_source(pinfo, decomp_tvb, "Decompressed SigComp message(Incomplete)");
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proto_tree_add_text(udvm_tree, decomp_tvb, 0, -1,"SigComp message Decompression failure");
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return decomp_tvb;
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}
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g_free(out_buff);
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return NULL;
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break;
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case SIGCOMP_INSTR_AND: /* 1 AND ($operand_1, %operand_2) */
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if (show_instr_detail_level == 2 ){
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
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"Addr: %u ## AND(1) (operand_1, operand_2)",
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current_address);
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}
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/* $operand_1*/
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operand_address = current_address + 1;
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next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
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if (show_instr_detail_level == 2 ){
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
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operand_address, operand_1);
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}
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operand_address = next_operand_address;
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/* %operand_2*/
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next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
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if (show_instr_detail_level == 2 ){
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
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operand_address, operand_2);
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}
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if (show_instr_detail_level == 1)
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{
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
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"Addr: %u ## AND (operand_1=%u, operand_2=%u)",
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current_address, operand_1, operand_2);
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}
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/* execute the instruction */
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result = operand_1 & operand_2;
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lsb = result & 0xff;
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msb = result >> 8;
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buff[result_dest] = msb;
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buff[(result_dest+1) & 0xffff] = lsb;
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if (print_level_1 ){
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
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result, result_dest);
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}
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current_address = next_operand_address;
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goto execute_next_instruction;
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break;
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case SIGCOMP_INSTR_OR: /* 2 OR ($operand_1, %operand_2) */
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if (show_instr_detail_level == 2 ){
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
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"Addr: %u ## OR(2) (operand_1, operand_2)",
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current_address);
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}
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/* $operand_1*/
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operand_address = current_address + 1;
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next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
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if (show_instr_detail_level == 2 ){
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
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operand_address, operand_1);
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}
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operand_address = next_operand_address;
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/* %operand_2*/
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next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
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if (show_instr_detail_level == 2 ){
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
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operand_address, operand_2);
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}
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if (show_instr_detail_level == 1)
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{
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proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
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"Addr: %u ## OR (operand_1=%u, operand_2=%u)",
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current_address, operand_1, operand_2);
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}
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/* execute the instruction */
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result = operand_1 | operand_2;
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lsb = result & 0xff;
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msb = result >> 8;
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buff[result_dest] = msb;
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buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_NOT: /* 3 NOT ($operand_1) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## NOT(3) ($operand_1)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## NOT (operand_1=%u)",
|
|
current_address, operand_1);
|
|
}
|
|
/* execute the instruction */
|
|
result = operand_1 ^ 0xffff;
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_LSHIFT: /* 4 LSHIFT ($operand_1, %operand_2) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## LSHIFT(4) ($operand_1, operand_2)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %operand_2*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
|
|
operand_address, operand_2);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## LSHIFT (operand_1=%u, operand_2=%u)",
|
|
current_address, operand_1, operand_2);
|
|
}
|
|
/* execute the instruction */
|
|
result = operand_1 << operand_2;
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
case SIGCOMP_INSTR_RSHIFT: /* 5 RSHIFT ($operand_1, %operand_2) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## RSHIFT(5) (operand_1, operand_2)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %operand_2*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
|
|
operand_address, operand_2);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## RSHIFT (operand_1=%u, operand_2=%u)",
|
|
current_address, operand_1, operand_2);
|
|
}
|
|
/* execute the instruction */
|
|
result = operand_1 >> operand_2;
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_ADD: /* 6 ADD ($operand_1, %operand_2) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## ADD(6) (operand_1, operand_2)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %operand_2*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
|
|
operand_address, operand_2);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## ADD (operand_1=%u, operand_2=%u)",
|
|
current_address, operand_1, operand_2);
|
|
}
|
|
/* execute the instruction */
|
|
result = operand_1 + operand_2;
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
|
|
case SIGCOMP_INSTR_SUBTRACT: /* 7 SUBTRACT ($operand_1, %operand_2) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## SUBTRACT(7) (operand_1, operand_2)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %operand_2*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
|
|
operand_address, operand_2);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## SUBTRACT (operand_1=%u, operand_2=%u)",
|
|
current_address, operand_1, operand_2);
|
|
}
|
|
/* execute the instruction */
|
|
result = operand_1 - operand_2;
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_MULTIPLY: /* 8 MULTIPLY ($operand_1, %operand_2) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ##MULTIPLY(8) (operand_1, operand_2)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %operand_2*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
|
|
operand_address, operand_2);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## MULTIPLY (operand_1=%u, operand_2=%u)",
|
|
current_address, operand_1, operand_2);
|
|
}
|
|
/*
|
|
* execute the instruction
|
|
* MULTIPLY (m, n) := m * n (modulo 2^16)
|
|
*/
|
|
if ( operand_2 == 0){
|
|
result_code = 4;
|
|
goto decompression_failure;
|
|
}
|
|
result = operand_1 * operand_2;
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_DIVIDE: /* 9 DIVIDE ($operand_1, %operand_2) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## DIVIDE(9) (operand_1, operand_2)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %operand_2*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
|
|
operand_address, operand_2);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## DIVIDE (operand_1=%u, operand_2=%u)",
|
|
current_address, operand_1, operand_2);
|
|
}
|
|
/*
|
|
* execute the instruction
|
|
* DIVIDE (m, n) := floor(m / n)
|
|
* Decompression failure occurs if a DIVIDE or REMAINDER instruction
|
|
* encounters an operand_2 that is zero.
|
|
*/
|
|
if ( operand_2 == 0){
|
|
result_code = 4;
|
|
goto decompression_failure;
|
|
}
|
|
result = operand_1 / operand_2;
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_REMAINDER: /* 10 REMAINDER ($operand_1, %operand_2) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## REMAINDER(10) (operand_1, operand_2)",
|
|
current_address);
|
|
}
|
|
/* $operand_1*/
|
|
operand_address = current_address + 1;
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &operand_1, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_1 %u",
|
|
operand_address, operand_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %operand_2*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &operand_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u operand_2 %u",
|
|
operand_address, operand_2);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## REMAINDER (operand_1=%u, operand_2=%u)",
|
|
current_address, operand_1, operand_2);
|
|
}
|
|
/*
|
|
* execute the instruction
|
|
* REMAINDER (m, n) := m - n * floor(m / n)
|
|
* Decompression failure occurs if a DIVIDE or REMAINDER instruction
|
|
* encounters an operand_2 that is zero.
|
|
*/
|
|
if ( operand_2 == 0){
|
|
result_code = 4;
|
|
goto decompression_failure;
|
|
}
|
|
result = operand_1 - operand_2 * (operand_1 / operand_2);
|
|
lsb = result & 0xff;
|
|
msb = result >> 8;
|
|
buff[result_dest] = msb;
|
|
buff[(result_dest+1) & 0xffff] = lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading result %u at %u",
|
|
result, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_SORT_ASCENDING: /* 11 SORT-ASCENDING (%start, %n, %k) */
|
|
/*
|
|
* used_udvm_cycles = 1 + k * (ceiling(log2(k)) + n)
|
|
*/
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## SORT-ASCENDING(11) (start, n, k))",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Execution of this instruction is NOT implemented");
|
|
/*
|
|
* used_udvm_cycles = 1 + k * (ceiling(log2(k)) + n)
|
|
*/
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_SORT_DESCENDING: /* 12 SORT-DESCENDING (%start, %n, %k) */
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## SORT-DESCENDING(12) (start, n, k))",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Execution of this instruction is NOT implemented");
|
|
/*
|
|
* used_udvm_cycles = 1 + k * (ceiling(log2(k)) + n)
|
|
*/
|
|
break;
|
|
case SIGCOMP_INSTR_SHA_1: /* 13 SHA-1 (%position, %length, %destination) */
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## SHA-1(13) (position, length, destination)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %position */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &position);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u position %u",
|
|
operand_address, position);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %length */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* $destination */
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &ref_destination, &result_dest);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u $destination %u",
|
|
operand_address, ref_destination);
|
|
}
|
|
current_address = next_operand_address;
|
|
used_udvm_cycles = used_udvm_cycles + length;
|
|
|
|
n = 0;
|
|
k = position;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, 0, -1,
|
|
"byte_copy_right = %u", byte_copy_right);
|
|
}
|
|
|
|
sha1_starts( &ctx );
|
|
|
|
while (n<length) {
|
|
guint16 handle_now = length;
|
|
|
|
if ( k < byte_copy_right && byte_copy_right <= k + (length-n) ){
|
|
handle_now = byte_copy_right - position;
|
|
}
|
|
|
|
if (k + handle_now >= UDVM_MEMORY_SIZE)
|
|
goto decompression_failure;
|
|
sha1_update( &ctx, &buff[k], handle_now );
|
|
|
|
k = ( k + handle_now ) & 0xffff;
|
|
n = ( n + handle_now ) & 0xffff;
|
|
|
|
if ( k >= byte_copy_right ) {
|
|
k = byte_copy_left;
|
|
}
|
|
}
|
|
|
|
sha1_finish( &ctx, sha1_digest_buf );
|
|
|
|
k = ref_destination;
|
|
|
|
for ( n=0; n< STATE_BUFFER_SIZE; n++ ) {
|
|
|
|
buff[k] = sha1_digest_buf[n];
|
|
|
|
k = ( k + 1 ) & 0xffff;
|
|
n++;
|
|
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
}
|
|
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, 0, -1,
|
|
"Calculated SHA-1: %s",
|
|
bytes_to_str(sha1_digest_buf, STATE_BUFFER_SIZE));
|
|
}
|
|
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_LOAD: /* 14 LOAD (%address, %value) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## LOAD(14) (%%address, %%value)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %address */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &addr);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Address %u",
|
|
operand_address, addr);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %value */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &value);
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## LOAD (%%address=%u, %%value=%u)",
|
|
current_address, addr, value);
|
|
}
|
|
lsb = value & 0xff;
|
|
msb = value >> 8;
|
|
|
|
buff[addr] = msb;
|
|
buff[(addr + 1) & 0xffff] = lsb;
|
|
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Value %u",
|
|
operand_address, value);
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Loading bytes at %u Value %u 0x%x",
|
|
addr, value, value);
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_MULTILOAD: /* 15 MULTILOAD (%address, #n, %value_0, ..., %value_n-1) */
|
|
/* RFC 3320:
|
|
* The MULTILOAD instruction sets a contiguous block of 2-byte words in
|
|
* the UDVM memory to specified values.
|
|
* Hmm what if the value to load only takes one byte ? Chose to always load two bytes.
|
|
*/
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## MULTILOAD(15) (%%address, #n, value_0, ..., value_n-1)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %address */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &addr);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Address %u",
|
|
operand_address, addr);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* #n */
|
|
next_operand_address = decode_udvm_literal_operand(buff,operand_address, &n);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u n %u",
|
|
operand_address, n);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## MULTILOAD (%%address=%u, #n=%u, value_0, ..., value_%d)",
|
|
current_address, addr, n, n-1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
used_udvm_cycles = used_udvm_cycles + n;
|
|
while ( n > 0) {
|
|
n = n - 1;
|
|
/* %value */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &value);
|
|
lsb = value & 0xff;
|
|
msb = value >> 8;
|
|
|
|
if (addr >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
|
|
buff[addr] = msb;
|
|
buff[(addr + 1) & 0xffff] = lsb;
|
|
/* debug
|
|
*/
|
|
length = next_operand_address - operand_address;
|
|
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1, "Addr: %u Value %5u - Loading bytes at %5u Value %5u 0x%x",
|
|
operand_address, value, addr, value, value);
|
|
}
|
|
addr = addr + 2;
|
|
operand_address = next_operand_address;
|
|
}
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_PUSH: /* 16 PUSH (%value) */
|
|
if (show_instr_detail_level == 2){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## PUSH(16) (value)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %value */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &value);
|
|
if (show_instr_detail_level == 2){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Value %u",
|
|
operand_address, value);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## PUSH (value=%u)",
|
|
current_address, value);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
/* Push the value address onto the stack */
|
|
stack_location = (buff[70] << 8) | buff[71];
|
|
stack_fill = (buff[stack_location] << 8)
|
|
| buff[(stack_location+1) & 0xFFFF];
|
|
addr = (stack_location + stack_fill * 2 + 2) & 0xFFFF;
|
|
|
|
if (addr >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
|
|
buff[addr] = (value >> 8) & 0x00FF;
|
|
buff[(addr+1) & 0xFFFF] = value & 0x00FF;
|
|
|
|
if (stack_location >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
|
|
stack_fill = (stack_fill + 1) & 0xFFFF;
|
|
buff[stack_location] = (stack_fill >> 8) & 0x00FF;
|
|
buff[(stack_location+1) & 0xFFFF] = stack_fill & 0x00FF;
|
|
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_POP: /* 17 POP (%address) */
|
|
if (show_instr_detail_level == 2){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## POP(16) (value)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %value */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &destination);
|
|
if (show_instr_detail_level == 2){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Value %u",
|
|
operand_address, destination);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## POP (address=%u)",
|
|
current_address, destination);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
/* Pop value from the top of the stack */
|
|
stack_location = (buff[70] << 8) | buff[71];
|
|
stack_fill = (buff[stack_location] << 8)
|
|
| buff[(stack_location+1) & 0xFFFF];
|
|
if (stack_fill == 0)
|
|
{
|
|
result_code = 16;
|
|
goto decompression_failure;
|
|
}
|
|
|
|
if (stack_location >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
|
|
stack_fill = (stack_fill - 1) & 0xFFFF;
|
|
buff[stack_location] = (stack_fill >> 8) & 0x00FF;
|
|
buff[(stack_location+1) & 0xFFFF] = stack_fill & 0x00FF;
|
|
|
|
addr = (stack_location + stack_fill * 2 + 2) & 0xFFFF;
|
|
|
|
if (addr >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
|
|
value = (buff[addr] << 8)
|
|
| buff[(addr+1) & 0xFFFF];
|
|
|
|
/* ... and store the popped value. */
|
|
if (destination >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
buff[destination] = (value >> 8) & 0x00FF;
|
|
buff[(destination+1) & 0xFFFF] = value & 0x00FF;
|
|
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_COPY: /* 18 COPY (%position, %length, %destination) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COPY(18) (position, length, destination)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %position */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &position);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u position %u",
|
|
operand_address, position);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %length */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %destination */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &destination);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Destination %u",
|
|
operand_address, destination);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COPY (position=%u, length=%u, destination=%u)",
|
|
current_address, position, length, destination);
|
|
}
|
|
current_address = next_operand_address;
|
|
/*
|
|
* 8.4. Byte copying
|
|
* :
|
|
* The string of bytes is copied in ascending order of memory address,
|
|
* respecting the bounds set by byte_copy_left and byte_copy_right.
|
|
* More precisely, if a byte is copied from/to Address m then the next
|
|
* byte is copied from/to Address n where n is calculated as follows:
|
|
*
|
|
* Set k := m + 1 (modulo 2^16)
|
|
* If k = byte_copy_right then set n := byte_copy_left, else set n := k
|
|
*
|
|
*/
|
|
|
|
n = 0;
|
|
k = destination;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" byte_copy_right = %u", byte_copy_right);
|
|
}
|
|
|
|
while ( n < length ){
|
|
buff[k] = buff[position];
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" Copying value: %u (0x%x) to Addr: %u",
|
|
buff[position], buff[position], k);
|
|
}
|
|
position = ( position + 1 ) & 0xffff;
|
|
k = ( k + 1 ) & 0xffff;
|
|
n++;
|
|
|
|
/*
|
|
* Check for circular buffer wrapping after the positions are
|
|
* incremented. If either started at BCR then they should continue
|
|
* to increment beyond BCR.
|
|
*/
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
if ( position == byte_copy_right ){
|
|
position = byte_copy_left;
|
|
}
|
|
}
|
|
used_udvm_cycles = used_udvm_cycles + length;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_COPY_LITERAL: /* 19 COPY-LITERAL (%position, %length, $destination) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COPY-LITERAL(19) (position, length, $destination)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %position */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &position);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u position %u",
|
|
operand_address, position);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %length */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
|
|
/* $destination */
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &ref_destination, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u destination %u",
|
|
operand_address, ref_destination);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COPY-LITERAL (position=%u, length=%u, $destination=%u)",
|
|
current_address, position, length, ref_destination);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
|
|
/*
|
|
* 8.4. Byte copying
|
|
* :
|
|
* The string of bytes is copied in ascending order of memory address,
|
|
* respecting the bounds set by byte_copy_left and byte_copy_right.
|
|
* More precisely, if a byte is copied from/to Address m then the next
|
|
* byte is copied from/to Address n where n is calculated as follows:
|
|
*
|
|
* Set k := m + 1 (modulo 2^16)
|
|
* If k = byte_copy_right then set n := byte_copy_left, else set n := k
|
|
*
|
|
*/
|
|
|
|
n = 0;
|
|
k = ref_destination;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" byte_copy_right = %u", byte_copy_right);
|
|
}
|
|
while ( n < length ){
|
|
|
|
buff[k] = buff[position];
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" Copying value: %u (0x%x) to Addr: %u",
|
|
buff[position], buff[position], k);
|
|
}
|
|
position = ( position + 1 ) & 0xffff;
|
|
k = ( k + 1 ) & 0xffff;
|
|
n++;
|
|
|
|
/*
|
|
* Check for circular buffer wrapping after the positions are
|
|
* incremented. It is important that k cannot be left set
|
|
* to BCR. Also, if either started at BCR then they should continue
|
|
* to increment beyond BCR.
|
|
*/
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
if ( position == byte_copy_right ){
|
|
position = byte_copy_left;
|
|
}
|
|
}
|
|
buff[result_dest] = k >> 8;
|
|
buff[(result_dest + 1) & 0xffff] = k & 0x00ff;
|
|
|
|
used_udvm_cycles = used_udvm_cycles + length;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_COPY_OFFSET: /* 20 COPY-OFFSET (%offset, %length, $destination) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COPY-OFFSET(20) (offset, length, $destination)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %offset */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &multy_offset);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u offset %u",
|
|
operand_address, multy_offset);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %length */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
|
|
/* $destination */
|
|
next_operand_address = dissect_udvm_reference_operand(buff, operand_address, &ref_destination, &result_dest);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u $destination %u",
|
|
operand_address, ref_destination);
|
|
}
|
|
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COPY-OFFSET (offset=%u, length=%u, $destination=%u)",
|
|
current_address, multy_offset, length, result_dest);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
/* Execute the instruction:
|
|
* To derive the value of the position operand, starting at the memory
|
|
* address specified by destination, the UDVM counts backwards a total
|
|
* of offset memory addresses.
|
|
*
|
|
* If the memory address specified in byte_copy_left is reached, the
|
|
* next memory address is taken to be (byte_copy_right - 1) modulo 2^16.
|
|
*/
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
|
|
/*
|
|
* In order to work out the position, simple arithmetic is tricky
|
|
* to apply because there some nasty corner cases. A simple loop
|
|
* is inefficient but the logic is simple.
|
|
*
|
|
* FUTURE: This could be optimised.
|
|
*/
|
|
for (position = ref_destination, i = 0; i < multy_offset; i++)
|
|
{
|
|
if ( position == byte_copy_left )
|
|
{
|
|
position = (byte_copy_right - 1) & 0xffff;
|
|
}
|
|
else
|
|
{
|
|
position = (position - 1) & 0xffff;
|
|
}
|
|
}
|
|
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" byte_copy_left = %u byte_copy_right = %u position= %u",
|
|
byte_copy_left, byte_copy_right, position);
|
|
}
|
|
/* The COPY-OFFSET instruction then behaves as a COPY-LITERAL
|
|
* instruction, taking the value of the position operand to be the last
|
|
* memory address reached in the above step.
|
|
*/
|
|
|
|
/*
|
|
* 8.4. Byte copying
|
|
* :
|
|
* The string of bytes is copied in ascending order of memory address,
|
|
* respecting the bounds set by byte_copy_left and byte_copy_right.
|
|
* More precisely, if a byte is copied from/to Address m then the next
|
|
* byte is copied from/to Address n where n is calculated as follows:
|
|
*
|
|
* Set k := m + 1 (modulo 2^16)
|
|
* If k = byte_copy_right then set n := byte_copy_left, else set n := k
|
|
*
|
|
*/
|
|
|
|
n = 0;
|
|
k = ref_destination;
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" byte_copy_left = %u byte_copy_right = %u", byte_copy_left, byte_copy_right);
|
|
}
|
|
while ( n < length ){
|
|
buff[k] = buff[position];
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" Copying value: %5u (0x%x) from Addr: %u to Addr: %u",
|
|
buff[position], buff[position],(position), k);
|
|
}
|
|
n++;
|
|
k = ( k + 1 ) & 0xffff;
|
|
position = ( position + 1 ) & 0xffff;
|
|
|
|
/*
|
|
* Check for circular buffer wrapping after the positions are
|
|
* incremented. It is important that k cannot be left set
|
|
* to BCR. Also, if either started at BCR then they should continue
|
|
* to increment beyond BCR.
|
|
*/
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
if ( position == byte_copy_right ){
|
|
position = byte_copy_left;
|
|
}
|
|
}
|
|
buff[result_dest] = k >> 8;
|
|
buff[result_dest + 1] = k & 0x00ff;
|
|
used_udvm_cycles = used_udvm_cycles + length;
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
case SIGCOMP_INSTR_MEMSET: /* 21 MEMSET (%address, %length, %start_value, %offset) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## MEMSET(21) (address, length, start_value, offset)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
|
|
/* %address */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &addr);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Address %u",
|
|
operand_address, addr);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %length, */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %start_value */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &start_value);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u start_value %u",
|
|
operand_address, start_value);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %offset */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &multy_offset);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u offset %u",
|
|
operand_address, multy_offset);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## MEMSET (address=%u, length=%u, start_value=%u, offset=%u)",
|
|
current_address, addr, length, start_value, multy_offset);
|
|
}
|
|
current_address = next_operand_address;
|
|
/* exetute the instruction
|
|
* The sequence of values used by the MEMSET instruction is specified by
|
|
* the following formula:
|
|
*
|
|
* Seq[n] := (start_value + n * offset) modulo 256
|
|
*/
|
|
n = 0;
|
|
k = addr;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" byte_copy_left = %u byte_copy_right = %u", byte_copy_left, byte_copy_right);
|
|
}
|
|
while ( n < length ){
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
buff[k] = (start_value + ( n * multy_offset)) & 0xff;
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" Storing value: %u (0x%x) at Addr: %u",
|
|
buff[k], buff[k], k);
|
|
}
|
|
k = ( k + 1 ) & 0xffff;
|
|
n++;
|
|
}/* end while */
|
|
used_udvm_cycles = used_udvm_cycles + length;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
|
|
case SIGCOMP_INSTR_JUMP: /* 22 JUMP (@address) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## JUMP(22) (@address)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* @address */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_address_operand(buff,operand_address, &at_address, current_address);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## JUMP (@address=%u)",
|
|
current_address, at_address);
|
|
}
|
|
current_address = at_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_COMPARE: /* 23 */
|
|
/* COMPARE (%value_1, %value_2, @address_1, @address_2, @address_3)
|
|
*/
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COMPARE(23) (value_1, value_2, @address_1, @address_2, @address_3)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
|
|
/* %value_1 */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &value_1);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Value %u",
|
|
operand_address, value_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %value_2 */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &value_2);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Value %u",
|
|
operand_address, value_2);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* @address_1 */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &at_address_1);
|
|
at_address_1 = ( current_address + at_address_1) & 0xffff;
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address_1);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
|
|
/* @address_2 */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &at_address_2);
|
|
at_address_2 = ( current_address + at_address_2) & 0xffff;
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address_2);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* @address_3 */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &at_address_3);
|
|
at_address_3 = ( current_address + at_address_3) & 0xffff;
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address_3);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## COMPARE (value_1=%u, value_2=%u, @address_1=%u, @address_2=%u, @address_3=%u)",
|
|
current_address, value_1, value_2, at_address_1, at_address_2, at_address_3);
|
|
}
|
|
/* execute the instruction
|
|
* If value_1 < value_2 then the UDVM continues instruction execution at
|
|
* the memory address specified by address 1. If value_1 = value_2 then
|
|
* it jumps to the address specified by address_2. If value_1 > value_2
|
|
* then it jumps to the address specified by address_3.
|
|
*/
|
|
if ( value_1 < value_2 )
|
|
current_address = at_address_1;
|
|
if ( value_1 == value_2 )
|
|
current_address = at_address_2;
|
|
if ( value_1 > value_2 )
|
|
current_address = at_address_3;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_CALL: /* 24 CALL (@address) (PUSH addr )*/
|
|
if (show_instr_detail_level == 2){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## CALL(24) (@address) (PUSH addr )",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* @address */
|
|
next_operand_address = decode_udvm_address_operand(buff,operand_address, &at_address, current_address);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## CALL (@address=%u)",
|
|
current_address, at_address);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
/* Push the current address onto the stack */
|
|
stack_location = (buff[70] << 8) | buff[71];
|
|
stack_fill = (buff[stack_location] << 8)
|
|
| buff[(stack_location+1) & 0xFFFF];
|
|
addr = (stack_location + stack_fill * 2 + 2) & 0xFFFF;
|
|
if (addr >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
buff[addr] = (current_address >> 8) & 0x00FF;
|
|
buff[(addr+1) & 0xFFFF] = current_address & 0x00FF;
|
|
|
|
stack_fill = (stack_fill + 1) & 0xFFFF;
|
|
if (stack_location >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
buff[stack_location] = (stack_fill >> 8) & 0x00FF;
|
|
buff[(stack_location+1) & 0xFFFF] = stack_fill & 0x00FF;
|
|
|
|
/* ... and jump to the destination address */
|
|
current_address = at_address;
|
|
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_RETURN: /* 25 POP and return */
|
|
if (print_level_1 || show_instr_detail_level == 1){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## POP(25) and return",
|
|
current_address);
|
|
}
|
|
|
|
/* Pop value from the top of the stack */
|
|
stack_location = (buff[70] << 8) | buff[71];
|
|
stack_fill = (buff[stack_location] << 8)
|
|
| buff[(stack_location+1) & 0xFFFF];
|
|
if (stack_fill == 0)
|
|
{
|
|
result_code = 16;
|
|
goto decompression_failure;
|
|
}
|
|
|
|
stack_fill = (stack_fill - 1) & 0xFFFF;
|
|
if (stack_location >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
buff[stack_location] = (stack_fill >> 8) & 0x00FF;
|
|
buff[(stack_location+1) & 0xFFFF] = stack_fill & 0x00FF;
|
|
|
|
addr = (stack_location + stack_fill * 2 + 2) & 0xFFFF;
|
|
at_address = (buff[addr] << 8)
|
|
| buff[(addr+1) & 0xFFFF];
|
|
|
|
/* ... and set the PC to the popped value */
|
|
current_address = at_address;
|
|
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_SWITCH: /* 26 SWITCH (#n, %j, @address_0, @address_1, ... , @address_n-1) */
|
|
/*
|
|
* When a SWITCH instruction is encountered the UDVM reads the value of
|
|
* j. It then continues instruction execution at the address specified
|
|
* by address j.
|
|
*
|
|
* Decompression failure occurs if j specifies a value of n or more, or
|
|
* if the address lies beyond the overall UDVM memory size.
|
|
*/
|
|
instruction_address = current_address;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## SWITCH (#n, j, @address_0, @address_1, ... , @address_n-1))",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* #n
|
|
* Number of addresses in the instruction
|
|
*/
|
|
next_operand_address = decode_udvm_literal_operand(buff,operand_address, &n);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u n %u",
|
|
operand_address, n);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %j */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &j);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u j %u",
|
|
operand_address, j);
|
|
}
|
|
operand_address = next_operand_address;
|
|
m = 0;
|
|
while ( m < n ){
|
|
/* @address_n-1 */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &at_address_1);
|
|
at_address_1 = ( instruction_address + at_address_1) & 0xffff;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address_1);
|
|
}
|
|
if ( j == m ){
|
|
current_address = at_address_1;
|
|
}
|
|
operand_address = next_operand_address;
|
|
m++;
|
|
}
|
|
/* Check decompression failure */
|
|
if ( ( j == n ) || ( j > n )){
|
|
result_code = 5;
|
|
goto decompression_failure;
|
|
}
|
|
if ( current_address > UDVM_MEMORY_SIZE ){
|
|
result_code = 6;
|
|
goto decompression_failure;
|
|
}
|
|
used_udvm_cycles = used_udvm_cycles + n;
|
|
|
|
goto execute_next_instruction;
|
|
|
|
break;
|
|
case SIGCOMP_INSTR_CRC: /* 27 CRC (%value, %position, %length, @address) */
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## CRC (value, position, length, @address)",
|
|
current_address);
|
|
}
|
|
|
|
operand_address = current_address + 1;
|
|
|
|
/* %value */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &value);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Value %u",
|
|
operand_address, value);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %position */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &position);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u position %u",
|
|
operand_address, position);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %length */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* @address */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &at_address);
|
|
at_address = ( current_address + at_address) & 0xffff;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address);
|
|
}
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
used_udvm_cycles = used_udvm_cycles + length;
|
|
|
|
n = 0;
|
|
k = position;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
result = 0;
|
|
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, 0, -1,
|
|
"byte_copy_right = %u", byte_copy_right);
|
|
}
|
|
|
|
while (n<length) {
|
|
|
|
guint16 handle_now = length - n;
|
|
|
|
if ( k < byte_copy_right && byte_copy_right <= k + (length-n) ){
|
|
handle_now = byte_copy_right - k;
|
|
}
|
|
|
|
if (k + handle_now >= UDVM_MEMORY_SIZE)
|
|
goto decompression_failure;
|
|
result = crc16_ccitt_seed(&buff[k], handle_now, (guint16) (result ^ 0xffff));
|
|
|
|
k = ( k + handle_now ) & 0xffff;
|
|
n = ( n + handle_now ) & 0xffff;
|
|
|
|
if ( k >= byte_copy_right ) {
|
|
k = byte_copy_left;
|
|
}
|
|
}
|
|
|
|
result = result ^ 0xffff;
|
|
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1, "Calculated CRC %u", result);
|
|
}
|
|
if (result != value){
|
|
current_address = at_address;
|
|
}
|
|
else {
|
|
current_address = next_operand_address;
|
|
}
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
|
|
case SIGCOMP_INSTR_INPUT_BYTES: /* 28 INPUT-BYTES (%length, %destination, @address) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## INPUT-BYTES(28) length, destination, @address)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/* %length */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %destination */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &destination);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Destination %u",
|
|
operand_address, destination);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* @address */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &at_address);
|
|
at_address = ( current_address + at_address) & 0xffff;
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## INPUT-BYTES length=%u, destination=%u, @address=%u)",
|
|
current_address, length, destination, at_address);
|
|
}
|
|
/* execute the instruction TODO insert checks
|
|
* RFC 3320 :
|
|
*
|
|
* 0 7 8 15
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | byte_copy_left | 64 - 65
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | byte_copy_right | 66 - 67
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | input_bit_order | 68 - 69
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | stack_location | 70 - 71
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
*
|
|
* Figure 7: Memory addresses of the UDVM registers
|
|
* :
|
|
* 8.4. Byte copying
|
|
* :
|
|
* The string of bytes is copied in ascending order of memory address,
|
|
* respecting the bounds set by byte_copy_left and byte_copy_right.
|
|
* More precisely, if a byte is copied from/to Address m then the next
|
|
* byte is copied from/to Address n where n is calculated as follows:
|
|
*
|
|
* Set k := m + 1 (modulo 2^16)
|
|
* If k = byte_copy_right then set n := byte_copy_left, else set n := k
|
|
*
|
|
*/
|
|
|
|
n = 0;
|
|
k = destination;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" byte_copy_right = %u", byte_copy_right);
|
|
}
|
|
/* clear out remaining bits if any */
|
|
remaining_bits = 0;
|
|
input_bits=0;
|
|
/* operand_address used as dummy */
|
|
while ( n < length ){
|
|
if (input_address > ( msg_end - 1)){
|
|
current_address = at_address;
|
|
result_code = 14;
|
|
goto execute_next_instruction;
|
|
}
|
|
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
octet = tvb_get_guint8(message_tvb, input_address);
|
|
buff[k] = octet;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" Loading value: %u (0x%x) at Addr: %u", octet, octet, k);
|
|
}
|
|
input_address++;
|
|
/*
|
|
* If the instruction requests data that lies beyond the end of the
|
|
* SigComp message, no data is returned. Instead the UDVM moves program
|
|
* execution to the address specified by the address operand.
|
|
*/
|
|
|
|
|
|
k = ( k + 1 ) & 0xffff;
|
|
n++;
|
|
}
|
|
used_udvm_cycles = used_udvm_cycles + length;
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_INPUT_BITS:/* 29 INPUT-BITS (%length, %destination, @address) */
|
|
/*
|
|
* The length operand indicates the requested number of bits.
|
|
* Decompression failure occurs if this operand does not lie between 0
|
|
* and 16 inclusive.
|
|
*
|
|
* The destination operand specifies the memory address to which the
|
|
* compressed data should be copied. Note that the requested bits are
|
|
* interpreted as a 2-byte integer ranging from 0 to 2^length - 1, as
|
|
* explained in Section 8.2.
|
|
*
|
|
* If the instruction requests data that lies beyond the end of the
|
|
* SigComp message, no data is returned. Instead the UDVM moves program
|
|
* execution to the address specified by the address operand.
|
|
*/
|
|
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## INPUT-BITS(29) (length, destination, @address)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
|
|
/* %length */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u length %u",
|
|
operand_address, length);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %destination */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &destination);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Destination %u",
|
|
operand_address, destination);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* @address */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_address_operand(buff,operand_address, &at_address, current_address);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## INPUT-BITS length=%u, destination=%u, @address=%u)",
|
|
current_address, length, destination, at_address);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
/*
|
|
* Execute actual instr.
|
|
* The input_bit_order register contains the following three flags:
|
|
*
|
|
* 0 7 8 15
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | reserved |F|H|P| 68 - 69
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
*/
|
|
input_bit_order = buff[68] << 8;
|
|
input_bit_order = input_bit_order | buff[69];
|
|
/*
|
|
* If the instruction requests data that lies beyond the end of the
|
|
* SigComp message, no data is returned. Instead the UDVM moves program
|
|
* execution to the address specified by the address operand.
|
|
*/
|
|
|
|
if ( length > 16 ){
|
|
result_code = 7;
|
|
goto decompression_failure;
|
|
}
|
|
if ( input_bit_order > 7 ){
|
|
result_code = 8;
|
|
goto decompression_failure;
|
|
}
|
|
|
|
/*
|
|
* Transfer F bit to bit_order to tell decomp dispatcher which bit order to use
|
|
*/
|
|
bit_order = ( input_bit_order & 0x0004 ) >> 2;
|
|
value = decomp_dispatch_get_bits( message_tvb, udvm_tree, bit_order,
|
|
buff, &old_input_bit_order, &remaining_bits,
|
|
&input_bits, &input_address, length, &result_code, msg_end);
|
|
if ( result_code == 11 ){
|
|
current_address = at_address;
|
|
goto execute_next_instruction;
|
|
}
|
|
msb = value >> 8;
|
|
lsb = value & 0x00ff;
|
|
if (destination >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
buff[destination] = msb;
|
|
buff[(destination + 1) & 0xffff]=lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" Loading value: %u (0x%x) at Addr: %u, remaining_bits: %u", value, value, destination, remaining_bits);
|
|
}
|
|
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_INPUT_HUFFMAN: /* 30 */
|
|
/*
|
|
* INPUT-HUFFMAN (%destination, @address, #n, %bits_1, %lower_bound_1,
|
|
* %upper_bound_1, %uncompressed_1, ... , %bits_n, %lower_bound_n,
|
|
* %upper_bound_n, %uncompressed_n)
|
|
*/
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## INPUT-HUFFMAN (destination, @address, #n, bits_1, lower_bound_1,upper_bound_1, uncompressed_1, ... , bits_n, lower_bound_n,upper_bound_n, uncompressed_n)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
|
|
/* %destination */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &destination);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u Destination %u",
|
|
operand_address, destination);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* @address */
|
|
/* operand_value = (memory_address_of_instruction + D) modulo 2^16 */
|
|
next_operand_address = decode_udvm_address_operand(buff,operand_address, &at_address, current_address);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u @Address %u",
|
|
operand_address, at_address);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* #n */
|
|
next_operand_address = decode_udvm_literal_operand(buff,operand_address, &n);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u n %u",
|
|
operand_address, n);
|
|
}
|
|
operand_address = next_operand_address;
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## INPUT-HUFFMAN (destination=%u, @address=%u, #n=%u, bits_1, lower_1,upper_1, unc_1, ... , bits_%d, lower_%d,upper_%d, unc_%d)",
|
|
current_address, destination, at_address, n, n, n, n, n);
|
|
}
|
|
|
|
used_udvm_cycles = used_udvm_cycles + n;
|
|
|
|
/*
|
|
* Note that if n = 0 then the INPUT-HUFFMAN instruction is ignored and
|
|
* program execution resumes at the following instruction.
|
|
* Decompression failure occurs if (bits_1 + ... + bits_n) > 16.
|
|
*
|
|
* In all other cases, the behavior of the INPUT-HUFFMAN instruction is
|
|
* defined below:
|
|
*
|
|
* 1. Set j := 1 and set H := 0.
|
|
*
|
|
* 2. Request bits_j compressed bits. Interpret the returned bits as an
|
|
* integer k from 0 to 2^bits_j - 1, as explained in Section 8.2.
|
|
*
|
|
* 3. Set H := H * 2^bits_j + k.
|
|
*
|
|
* 4. If data is requested that lies beyond the end of the SigComp
|
|
* message, terminate the INPUT-HUFFMAN instruction and move program
|
|
* execution to the memory address specified by the address operand.
|
|
*
|
|
* 5. If (H < lower_bound_j) or (H > upper_bound_j) then set j := j + 1.
|
|
* Then go back to Step 2, unless j > n in which case decompression
|
|
* failure occurs.
|
|
*
|
|
* 6. Copy (H + uncompressed_j - lower_bound_j) modulo 2^16 to the
|
|
* memory address specified by the destination operand.
|
|
*
|
|
*/
|
|
/*
|
|
* The input_bit_order register contains the following three flags:
|
|
*
|
|
* 0 7 8 15
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
* | reserved |F|H|P| 68 - 69
|
|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
*
|
|
* Transfer H bit to bit_order to tell decomp dispatcher which bit order to use
|
|
*/
|
|
input_bit_order = buff[68] << 8;
|
|
input_bit_order = input_bit_order | buff[69];
|
|
bit_order = ( input_bit_order & 0x0002 ) >> 1;
|
|
|
|
j = 1;
|
|
H = 0;
|
|
m = n;
|
|
outside_huffman_boundaries = TRUE;
|
|
print_in_loop = print_level_3;
|
|
while ( m > 0 ){
|
|
/* %bits_n */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &bits_n);
|
|
if (print_in_loop ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u bits_n %u",
|
|
operand_address, bits_n);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/* %lower_bound_n */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &lower_bound_n);
|
|
if (print_in_loop ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u lower_bound_n %u",
|
|
operand_address, lower_bound_n);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %upper_bound_n */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &upper_bound_n);
|
|
if (print_in_loop ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u upper_bound_n %u",
|
|
operand_address, upper_bound_n);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* %uncompressed_n */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &uncompressed_n);
|
|
if (print_in_loop ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u uncompressed_n %u",
|
|
operand_address, uncompressed_n);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* execute instruction */
|
|
if ( outside_huffman_boundaries ) {
|
|
/*
|
|
* 2. Request bits_j compressed bits. Interpret the returned bits as an
|
|
* integer k from 0 to 2^bits_j - 1, as explained in Section 8.2.
|
|
*/
|
|
k = decomp_dispatch_get_bits( message_tvb, udvm_tree, bit_order,
|
|
buff, &old_input_bit_order, &remaining_bits,
|
|
&input_bits, &input_address, bits_n, &result_code, msg_end);
|
|
if ( result_code == 11 ){
|
|
/*
|
|
* 4. If data is requested that lies beyond the end of the SigComp
|
|
* message, terminate the INPUT-HUFFMAN instruction and move program
|
|
* execution to the memory address specified by the address operand.
|
|
*/
|
|
current_address = at_address;
|
|
goto execute_next_instruction;
|
|
}
|
|
|
|
/*
|
|
* 3. Set H := H * 2^bits_j + k.
|
|
* [In practice is a shift+OR operation.]
|
|
*/
|
|
oldH = H;
|
|
H = (H << bits_n) | k;
|
|
if (print_level_3 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," Set H(%u) := H(%u) * 2^bits_j(%u) + k(%u)",
|
|
H ,oldH, 1<<bits_n,k);
|
|
}
|
|
|
|
/*
|
|
* 5. If (H < lower_bound_j) or (H > upper_bound_j) then set j := j + 1.
|
|
* Then go back to Step 2, unless j > n in which case decompression
|
|
* failure occurs.
|
|
*/
|
|
if ((H < lower_bound_n) || (H > upper_bound_n)){
|
|
outside_huffman_boundaries = TRUE;
|
|
}else{
|
|
outside_huffman_boundaries = FALSE;
|
|
print_in_loop = FALSE;
|
|
/*
|
|
* 6. Copy (H + uncompressed_j - lower_bound_j) modulo 2^16 to the
|
|
* memory address specified by the destination operand.
|
|
*/
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
" H(%u) = H(%u) + uncompressed_n(%u) - lower_bound_n(%u)",
|
|
(H + uncompressed_n - lower_bound_n ),H, uncompressed_n, lower_bound_n);
|
|
}
|
|
H = H + uncompressed_n - lower_bound_n;
|
|
msb = H >> 8;
|
|
lsb = H & 0x00ff;
|
|
if (destination >= UDVM_MEMORY_SIZE - 1)
|
|
goto decompression_failure;
|
|
buff[destination] = msb;
|
|
buff[(destination + 1) & 0xffff]=lsb;
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" Loading H: %u (0x%x) at Addr: %u,j = %u remaining_bits: %u",
|
|
H, H, destination,( n - m + 1 ), remaining_bits);
|
|
}
|
|
|
|
}
|
|
|
|
|
|
}
|
|
m = m - 1;
|
|
}
|
|
if ( outside_huffman_boundaries ) {
|
|
result_code = 10;
|
|
goto decompression_failure;
|
|
}
|
|
|
|
current_address = next_operand_address;
|
|
goto execute_next_instruction;
|
|
break;
|
|
|
|
case SIGCOMP_INSTR_STATE_ACCESS: /* 31 */
|
|
/* STATE-ACCESS (%partial_identifier_start, %partial_identifier_length,
|
|
* %state_begin, %state_length, %state_address, %state_instruction)
|
|
*/
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## STATE-ACCESS(31) (partial_identifier_start, partial_identifier_length,state_begin, state_length, state_address, state_instruction)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
|
|
/*
|
|
* %partial_identifier_start
|
|
*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &p_id_start);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u partial_identifier_start %u",
|
|
operand_address, p_id_start);
|
|
}
|
|
|
|
/*
|
|
* %partial_identifier_length
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &p_id_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u partial_identifier_length %u",
|
|
operand_address, p_id_length);
|
|
}
|
|
/*
|
|
* %state_begin
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_begin);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_begin %u",
|
|
operand_address, state_begin);
|
|
}
|
|
/*
|
|
* %state_length
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_length %u",
|
|
operand_address, state_length);
|
|
}
|
|
/*
|
|
* %state_address
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_address);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_address %u",
|
|
operand_address, state_address);
|
|
}
|
|
/*
|
|
* %state_instruction
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_instruction);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_instruction %u",
|
|
operand_address, state_instruction);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## STATE-ACCESS(31) (partial_identifier_start=%u, partial_identifier_length=%u,state_begin=%u, state_length=%u, state_address=%u, state_instruction=%u)",
|
|
current_address, p_id_start, p_id_length, state_begin, state_length, state_address, state_instruction);
|
|
}
|
|
current_address = next_operand_address;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
if (print_level_2 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, input_address, 1,
|
|
" byte_copy_right = %u, byte_copy_left = %u", byte_copy_right,byte_copy_left);
|
|
}
|
|
|
|
result_code = udvm_state_access(message_tvb, udvm_tree, buff, p_id_start, p_id_length, state_begin, &state_length,
|
|
&state_address, &state_instruction, hf_id);
|
|
if ( result_code != 0 ){
|
|
goto decompression_failure;
|
|
}
|
|
used_udvm_cycles = used_udvm_cycles + state_length;
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_STATE_CREATE: /* 32 */
|
|
/*
|
|
* STATE-CREATE (%state_length, %state_address, %state_instruction,
|
|
* %minimum_access_length, %state_retention_priority)
|
|
*/
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## STATE-CREATE(32) (state_length, state_address, state_instruction,minimum_access_length, state_retention_priority)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
|
|
/*
|
|
* %state_length
|
|
*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_length %u",
|
|
operand_address, state_length);
|
|
}
|
|
/*
|
|
* %state_address
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_address);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_address %u",
|
|
operand_address, state_address);
|
|
}
|
|
/*
|
|
* %state_instruction
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_instruction);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_instruction %u",
|
|
operand_address, state_instruction);
|
|
}
|
|
/*
|
|
* %minimum_access_length
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &minimum_access_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u minimum_access_length %u",
|
|
operand_address, minimum_access_length);
|
|
}
|
|
/*
|
|
* %state_retention_priority
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_retention_priority);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_retention_priority %u",
|
|
operand_address, state_retention_priority);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## STATE-CREATE(32) (state_length=%u, state_address=%u, state_instruction=%u,minimum_access_length=%u, state_retention_priority=%u)",
|
|
current_address, state_length, state_address, state_instruction,minimum_access_length, state_retention_priority);
|
|
}
|
|
current_address = next_operand_address;
|
|
/* Execute the instruction
|
|
* TODO Implement the instruction
|
|
* RFC3320:
|
|
* Note that the new state item cannot be created until a valid
|
|
* compartment identifier has been returned by the application.
|
|
* Consequently, when a STATE-CREATE instruction is encountered the UDVM
|
|
* simply buffers the five supplied operands until the END-MESSAGE
|
|
* instruction is reached. The steps taken at this point are described
|
|
* in Section 9.4.9.
|
|
*
|
|
* Decompression failure MUST occur if more than four state creation
|
|
* requests are made before the END-MESSAGE instruction is encountered.
|
|
* Decompression failure also occurs if the minimum_access_length does
|
|
* not lie between 6 and 20 inclusive, or if the
|
|
* state_retention_priority is 65535.
|
|
*/
|
|
no_of_state_create++;
|
|
if ( no_of_state_create > 4 ){
|
|
result_code = 12;
|
|
goto decompression_failure;
|
|
}
|
|
if (( minimum_access_length < 6 ) || ( minimum_access_length > STATE_BUFFER_SIZE )){
|
|
result_code = 1;
|
|
goto decompression_failure;
|
|
}
|
|
if ( state_retention_priority == 65535 ){
|
|
result_code = 13;
|
|
goto decompression_failure;
|
|
}
|
|
state_length_buff[no_of_state_create] = state_length;
|
|
state_address_buff[no_of_state_create] = state_address;
|
|
state_instruction_buff[no_of_state_create] = state_instruction;
|
|
state_minimum_access_length_buff[no_of_state_create] = minimum_access_length;
|
|
/* state_state_retention_priority_buff[no_of_state_create] = state_retention_priority; */
|
|
used_udvm_cycles = used_udvm_cycles + state_length;
|
|
/* Debug */
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
n = 0;
|
|
k = state_address;
|
|
while ( n < state_length ){
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
string[0]= buff[k];
|
|
string[1]= '\0';
|
|
if (print_level_3 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
" Addr: %5u State value: %u (0x%x) ASCII(%s)",
|
|
k,buff[k],buff[k],format_text(string, 1));
|
|
}
|
|
k = ( k + 1 ) & 0xffff;
|
|
n++;
|
|
}
|
|
/* End debug */
|
|
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_STATE_FREE: /* 33 */
|
|
/*
|
|
* STATE-FREE (%partial_identifier_start, %partial_identifier_length)
|
|
*/
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## STATE-FREE (partial_identifier_start, partial_identifier_length)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/*
|
|
* %partial_identifier_start
|
|
*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &p_id_start);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u partial_identifier_start %u",
|
|
operand_address, p_id_start);
|
|
}
|
|
operand_address = next_operand_address;
|
|
|
|
/*
|
|
* %partial_identifier_length
|
|
*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &p_id_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u partial_identifier_length %u",
|
|
operand_address, p_id_length);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## STATE-FREE (partial_identifier_start=%u, partial_identifier_length=%u)",
|
|
current_address, p_id_start, p_id_length);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
/* Execute the instruction:
|
|
* TODO implement it
|
|
*/
|
|
udvm_state_free(buff,p_id_start,p_id_length);
|
|
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_OUTPUT: /* 34 OUTPUT (%output_start, %output_length) */
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## OUTPUT(34) (output_start, output_length)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
/*
|
|
* %output_start
|
|
*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &output_start);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u output_start %u",
|
|
operand_address, output_start);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/*
|
|
* %output_length
|
|
*/
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &output_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u output_length %u",
|
|
operand_address, output_length);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## OUTPUT (output_start=%u, output_length=%u)",
|
|
current_address, output_start, output_length);
|
|
}
|
|
current_address = next_operand_address;
|
|
|
|
/*
|
|
* Execute instruction
|
|
* 8.4. Byte copying
|
|
* :
|
|
* The string of bytes is copied in ascending order of memory address,
|
|
* respecting the bounds set by byte_copy_left and byte_copy_right.
|
|
* More precisely, if a byte is copied from/to Address m then the next
|
|
* byte is copied from/to Address n where n is calculated as follows:
|
|
*
|
|
* Set k := m + 1 (modulo 2^16)
|
|
* If k = byte_copy_right then set n := byte_copy_left, else set n := k
|
|
*
|
|
*/
|
|
|
|
n = 0;
|
|
k = output_start;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
if (print_level_3 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
" byte_copy_right = %u", byte_copy_right);
|
|
}
|
|
while ( n < output_length ){
|
|
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
out_buff[output_address] = buff[k];
|
|
string[0]= buff[k];
|
|
string[1]= '\0';
|
|
if (print_level_3 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
" Output value: %u (0x%x) ASCII(%s) from Addr: %u ,output to dispatcher position %u",
|
|
buff[k],buff[k],format_text(string,1), k,output_address);
|
|
}
|
|
k = ( k + 1 ) & 0xffff;
|
|
output_address ++;
|
|
n++;
|
|
}
|
|
used_udvm_cycles = used_udvm_cycles + output_length;
|
|
goto execute_next_instruction;
|
|
break;
|
|
case SIGCOMP_INSTR_END_MESSAGE: /* 35 */
|
|
/*
|
|
* END-MESSAGE (%requested_feedback_location,
|
|
* %returned_parameters_location, %state_length, %state_address,
|
|
* %state_instruction, %minimum_access_length,
|
|
* %state_retention_priority)
|
|
*/
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## END-MESSAGE (requested_feedback_location,state_instruction, minimum_access_length,state_retention_priority)",
|
|
current_address);
|
|
}
|
|
operand_address = current_address + 1;
|
|
|
|
/* %requested_feedback_location */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &requested_feedback_location);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u requested_feedback_location %u",
|
|
operand_address, requested_feedback_location);
|
|
}
|
|
operand_address = next_operand_address;
|
|
/* returned_parameters_location */
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &returned_parameters_location);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u returned_parameters_location %u",
|
|
operand_address, returned_parameters_location);
|
|
}
|
|
/*
|
|
* %state_length
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_length %u",
|
|
operand_address, state_length);
|
|
}
|
|
/*
|
|
* %state_address
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_address);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_address %u",
|
|
operand_address, state_address);
|
|
}
|
|
/*
|
|
* %state_instruction
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_instruction);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_instruction %u",
|
|
operand_address, state_instruction);
|
|
}
|
|
|
|
/*
|
|
* %minimum_access_length
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &minimum_access_length);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u minimum_access_length %u",
|
|
operand_address, minimum_access_length);
|
|
}
|
|
|
|
/*
|
|
* %state_retention_priority
|
|
*/
|
|
operand_address = next_operand_address;
|
|
next_operand_address = decode_udvm_multitype_operand(buff, operand_address, &state_retention_priority);
|
|
if (show_instr_detail_level == 2 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"Addr: %u state_retention_priority %u",
|
|
operand_address, state_retention_priority);
|
|
}
|
|
if (show_instr_detail_level == 1)
|
|
{
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,
|
|
"Addr: %u ## END-MESSAGE (requested_feedback_location=%u, returned_parameters_location=%u, state_length=%u, state_address=%u, state_instruction=%u, minimum_access_length=%u, state_retention_priority=%u)",
|
|
current_address, requested_feedback_location, returned_parameters_location, state_length, state_address, state_instruction, minimum_access_length,state_retention_priority);
|
|
}
|
|
current_address = next_operand_address;
|
|
/* TODO: This isn't currently totaly correct as END_INSTRUCTION might not create state */
|
|
no_of_state_create++;
|
|
if ( no_of_state_create > 4 ){
|
|
result_code = 12;
|
|
goto decompression_failure;
|
|
}
|
|
state_length_buff[no_of_state_create] = state_length;
|
|
state_address_buff[no_of_state_create] = state_address;
|
|
state_instruction_buff[no_of_state_create] = state_instruction;
|
|
/* Not used ? */
|
|
state_minimum_access_length_buff[no_of_state_create] = minimum_access_length;
|
|
/* state_state_retention_priority_buff[no_of_state_create] = state_retention_priority; */
|
|
|
|
/* Execute the instruction
|
|
*/
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"no_of_state_create %u",no_of_state_create);
|
|
if ( no_of_state_create != 0 ){
|
|
memset(sha1_digest_buf, 0, STATE_BUFFER_SIZE);
|
|
n = 1;
|
|
byte_copy_right = buff[66] << 8;
|
|
byte_copy_right = byte_copy_right | buff[67];
|
|
byte_copy_left = buff[64] << 8;
|
|
byte_copy_left = byte_copy_left | buff[65];
|
|
while ( n < no_of_state_create + 1 ){
|
|
sha1buff = g_malloc(state_length_buff[n]+8);
|
|
sha1buff[0] = state_length_buff[n] >> 8;
|
|
sha1buff[1] = state_length_buff[n] & 0xff;
|
|
sha1buff[2] = state_address_buff[n] >> 8;
|
|
sha1buff[3] = state_address_buff[n] & 0xff;
|
|
sha1buff[4] = state_instruction_buff[n] >> 8;
|
|
sha1buff[5] = state_instruction_buff[n] & 0xff;
|
|
sha1buff[6] = state_minimum_access_length_buff[n] >> 8;
|
|
sha1buff[7] = state_minimum_access_length_buff[n] & 0xff;
|
|
if (print_level_3 ){
|
|
for( x=0; x < 8; x++){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"sha1buff %u 0x%x",
|
|
x,sha1buff[x]);
|
|
}
|
|
}
|
|
k = state_address_buff[n];
|
|
for( x=0; x < state_length_buff[n]; x++)
|
|
{
|
|
if ( k == byte_copy_right ){
|
|
k = byte_copy_left;
|
|
}
|
|
sha1buff[8+x] = buff[k];
|
|
k = ( k + 1 ) & 0xffff;
|
|
}
|
|
|
|
sha1_starts( &ctx );
|
|
sha1_update( &ctx, (guint8 *) sha1buff, state_length_buff[n] + 8);
|
|
sha1_finish( &ctx, sha1_digest_buf );
|
|
if (print_level_3 ){
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"SHA1 digest %s",bytes_to_str(sha1_digest_buf, STATE_BUFFER_SIZE));
|
|
|
|
}
|
|
/* begin partial state-id change cco@iptel.org */
|
|
#if 0
|
|
udvm_state_create(sha1buff, sha1_digest_buf, state_minimum_access_length_buff[n]);
|
|
#endif
|
|
udvm_state_create(sha1buff, sha1_digest_buf, STATE_MIN_ACCESS_LEN);
|
|
/* end partial state-id change cco@iptel.org */
|
|
proto_tree_add_text(udvm_tree,bytecode_tvb, 0, -1,"### Creating state ###");
|
|
proto_tree_add_string(udvm_tree,hf_id, bytecode_tvb, 0, 0, bytes_to_str(sha1_digest_buf, state_minimum_access_length_buff[n]));
|
|
|
|
n++;
|
|
|
|
}
|
|
}
|
|
|
|
|
|
|
|
/* At least something got decompressed, show it */
|
|
decomp_tvb = tvb_new_child_real_data(message_tvb, out_buff,output_address,output_address);
|
|
/* Arrange that the allocated packet data copy be freed when the
|
|
* tvbuff is freed.
|
|
*/
|
|
tvb_set_free_cb( decomp_tvb, g_free );
|
|
|
|
add_new_data_source(pinfo, decomp_tvb, "Decompressed SigComp message");
|
|
/*
|
|
proto_tree_add_text(udvm_tree, decomp_tvb, 0, -1,"SigComp message Decompressed");
|
|
*/
|
|
used_udvm_cycles = used_udvm_cycles + state_length;
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"maximum_UDVM_cycles %u used_udvm_cycles %u",
|
|
maximum_UDVM_cycles, used_udvm_cycles);
|
|
return decomp_tvb;
|
|
break;
|
|
|
|
default:
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1," ### Addr %u Invalid instruction: %u (0x%x)",
|
|
current_address,current_instruction,current_instruction);
|
|
break;
|
|
}
|
|
g_free(out_buff);
|
|
return NULL;
|
|
decompression_failure:
|
|
|
|
proto_tree_add_text(udvm_tree, bytecode_tvb, 0, -1,"DECOMPRESSION FAILURE: %s",
|
|
val_to_str(result_code, result_code_vals,"Unknown (%u)"));
|
|
THROW(ReportedBoundsError);
|
|
g_free(out_buff);
|
|
return NULL;
|
|
|
|
}
|
|
|
|
/* The simplest operand type is the literal (#), which encodes a
|
|
* constant integer from 0 to 65535 inclusive. A literal operand may
|
|
* require between 1 and 3 bytes depending on its value.
|
|
* Bytecode: Operand value: Range:
|
|
* 0nnnnnnn N 0 - 127
|
|
* 10nnnnnn nnnnnnnn N 0 - 16383
|
|
* 11000000 nnnnnnnn nnnnnnnn N 0 - 65535
|
|
*
|
|
* Figure 8: Bytecode for a literal (#) operand
|
|
*
|
|
*/
|
|
static int
|
|
decode_udvm_literal_operand(guint8 *buff,guint operand_address, guint16 *value)
|
|
{
|
|
guint bytecode;
|
|
guint16 operand;
|
|
guint test_bits;
|
|
guint offset = operand_address;
|
|
guint8 temp_data;
|
|
|
|
bytecode = buff[operand_address];
|
|
test_bits = bytecode >> 7;
|
|
if (test_bits == 1){
|
|
test_bits = bytecode >> 6;
|
|
if (test_bits == 2){
|
|
/*
|
|
* 10nnnnnn nnnnnnnn N 0 - 16383
|
|
*/
|
|
temp_data = buff[operand_address] & 0x1f;
|
|
operand = temp_data << 8;
|
|
temp_data = buff[(operand_address + 1) & 0xffff];
|
|
operand = operand | temp_data;
|
|
*value = operand;
|
|
offset = offset + 2;
|
|
|
|
}else{
|
|
/*
|
|
* 111000000 nnnnnnnn nnnnnnnn N 0 - 65535
|
|
*/
|
|
offset ++;
|
|
temp_data = buff[operand_address] & 0x1f;
|
|
operand = temp_data << 8;
|
|
temp_data = buff[(operand_address + 1) & 0xffff];
|
|
operand = operand | temp_data;
|
|
*value = operand;
|
|
offset = offset + 2;
|
|
|
|
}
|
|
}else{
|
|
/*
|
|
* 0nnnnnnn N 0 - 127
|
|
*/
|
|
operand = ( bytecode & 0x7f);
|
|
*value = operand;
|
|
offset ++;
|
|
}
|
|
|
|
return offset;
|
|
|
|
}
|
|
|
|
/*
|
|
* The second operand type is the reference ($), which is always used to
|
|
* access a 2-byte value located elsewhere in the UDVM memory. The
|
|
* bytecode for a reference operand is decoded to be a constant integer
|
|
* from 0 to 65535 inclusive, which is interpreted as the memory address
|
|
* containing the actual value of the operand.
|
|
* Bytecode: Operand value: Range:
|
|
*
|
|
* 0nnnnnnn memory[2 * N] 0 - 65535
|
|
* 10nnnnnn nnnnnnnn memory[2 * N] 0 - 65535
|
|
* 11000000 nnnnnnnn nnnnnnnn memory[N] 0 - 65535
|
|
*
|
|
* Figure 9: Bytecode for a reference ($) operand
|
|
*/
|
|
static int
|
|
dissect_udvm_reference_operand(guint8 *buff,guint operand_address, guint16 *value,guint *result_dest)
|
|
{
|
|
guint bytecode;
|
|
guint16 operand;
|
|
guint offset = operand_address;
|
|
guint test_bits;
|
|
guint8 temp_data;
|
|
guint16 temp_data16;
|
|
|
|
bytecode = buff[operand_address];
|
|
test_bits = bytecode >> 7;
|
|
if (test_bits == 1){
|
|
test_bits = bytecode >> 6;
|
|
if (test_bits == 2){
|
|
/*
|
|
* 10nnnnnn nnnnnnnn memory[2 * N] 0 - 65535
|
|
*/
|
|
temp_data = buff[operand_address] & 0x3f;
|
|
operand = temp_data << 8;
|
|
temp_data = buff[(operand_address + 1) & 0xffff];
|
|
operand = operand | temp_data;
|
|
operand = (operand * 2);
|
|
*result_dest = operand;
|
|
temp_data16 = buff[operand] << 8;
|
|
temp_data16 = temp_data16 | buff[(operand+1) & 0xffff];
|
|
*value = temp_data16;
|
|
offset = offset + 2;
|
|
|
|
}else{
|
|
/*
|
|
* 11000000 nnnnnnnn nnnnnnnn memory[N] 0 - 65535
|
|
*/
|
|
operand_address++;
|
|
operand = buff[operand_address] << 8;
|
|
operand = operand | buff[(operand_address + 1) & 0xffff];
|
|
*result_dest = operand;
|
|
temp_data16 = buff[operand] << 8;
|
|
temp_data16 = temp_data16 | buff[(operand+1) & 0xffff];
|
|
*value = temp_data16;
|
|
offset = offset + 3;
|
|
|
|
}
|
|
}else{
|
|
/*
|
|
* 0nnnnnnn memory[2 * N] 0 - 65535
|
|
*/
|
|
operand = ( bytecode & 0x7f);
|
|
operand = (operand * 2);
|
|
*result_dest = operand;
|
|
temp_data16 = buff[operand] << 8;
|
|
temp_data16 = temp_data16 | buff[(operand+1) & 0xffff];
|
|
*value = temp_data16;
|
|
offset ++;
|
|
}
|
|
|
|
if (offset >= UDVM_MEMORY_SIZE || *result_dest >= UDVM_MEMORY_SIZE - 1 )
|
|
THROW(ReportedBoundsError);
|
|
|
|
return offset;
|
|
}
|
|
|
|
/* RFC3320
|
|
* Figure 10: Bytecode for a multitype (%) operand
|
|
* Bytecode: Operand value: Range: HEX val
|
|
* 00nnnnnn N 0 - 63 0x00
|
|
* 01nnnnnn memory[2 * N] 0 - 65535 0x40
|
|
* 1000011n 2 ^ (N + 6) 64 , 128 0x86
|
|
* 10001nnn 2 ^ (N + 8) 256 , ... , 32768 0x88
|
|
* 111nnnnn N + 65504 65504 - 65535 0xe0
|
|
* 1001nnnn nnnnnnnn N + 61440 61440 - 65535 0x90
|
|
* 101nnnnn nnnnnnnn N 0 - 8191 0xa0
|
|
* 110nnnnn nnnnnnnn memory[N] 0 - 65535 0xc0
|
|
* 10000000 nnnnnnnn nnnnnnnn N 0 - 65535 0x80
|
|
* 10000001 nnnnnnnn nnnnnnnn memory[N] 0 - 65535 0x81
|
|
*/
|
|
static int
|
|
decode_udvm_multitype_operand(guint8 *buff,guint operand_address, guint16 *value)
|
|
{
|
|
guint test_bits;
|
|
guint bytecode;
|
|
guint offset = operand_address;
|
|
guint16 operand;
|
|
guint32 result;
|
|
guint8 temp_data;
|
|
guint16 temp_data16;
|
|
guint16 memmory_addr = 0;
|
|
|
|
*value = 0;
|
|
|
|
bytecode = buff[operand_address];
|
|
test_bits = ( bytecode & 0xc0 ) >> 6;
|
|
switch (test_bits ){
|
|
case 0:
|
|
/*
|
|
* 00nnnnnn N 0 - 63
|
|
*/
|
|
operand = buff[operand_address];
|
|
/* debug
|
|
*g_warning("Reading 0x%x From address %u",operand,offset);
|
|
*/
|
|
*value = operand;
|
|
offset ++;
|
|
break;
|
|
case 1:
|
|
/*
|
|
* 01nnnnnn memory[2 * N] 0 - 65535
|
|
*/
|
|
memmory_addr = ( bytecode & 0x3f) * 2;
|
|
temp_data16 = buff[memmory_addr] << 8;
|
|
temp_data16 = temp_data16 | buff[(memmory_addr+1) & 0xffff];
|
|
*value = temp_data16;
|
|
offset ++;
|
|
break;
|
|
case 2:
|
|
/* Check tree most significant bits */
|
|
test_bits = ( bytecode & 0xe0 ) >> 5;
|
|
if ( test_bits == 5 ){
|
|
/*
|
|
* 101nnnnn nnnnnnnn N 0 - 8191
|
|
*/
|
|
temp_data = buff[operand_address] & 0x1f;
|
|
operand = temp_data << 8;
|
|
temp_data = buff[(operand_address + 1) & 0xffff];
|
|
operand = operand | temp_data;
|
|
*value = operand;
|
|
offset = offset + 2;
|
|
}else{
|
|
test_bits = ( bytecode & 0xf0 ) >> 4;
|
|
if ( test_bits == 9 ){
|
|
/*
|
|
* 1001nnnn nnnnnnnn N + 61440 61440 - 65535
|
|
*/
|
|
temp_data = buff[operand_address] & 0x0f;
|
|
operand = temp_data << 8;
|
|
temp_data = buff[(operand_address + 1) & 0xffff];
|
|
operand = operand | temp_data;
|
|
operand = operand + 61440;
|
|
*value = operand;
|
|
offset = offset + 2;
|
|
}else{
|
|
test_bits = ( bytecode & 0x08 ) >> 3;
|
|
if ( test_bits == 1){
|
|
/*
|
|
* 10001nnn 2 ^ (N + 8) 256 , ... , 32768
|
|
*/
|
|
|
|
result = 1 << ((buff[operand_address] & 0x07) + 8);
|
|
operand = result & 0xffff;
|
|
*value = operand;
|
|
offset ++;
|
|
}else{
|
|
test_bits = ( bytecode & 0x0e ) >> 1;
|
|
if ( test_bits == 3 ){
|
|
/*
|
|
* 1000 011n 2 ^ (N + 6) 64 , 128
|
|
*/
|
|
result = 1 << ((buff[operand_address] & 0x01) + 6);
|
|
operand = result & 0xffff;
|
|
*value = operand;
|
|
offset ++;
|
|
}else{
|
|
/*
|
|
* 1000 0000 nnnnnnnn nnnnnnnn N 0 - 65535
|
|
* 1000 0001 nnnnnnnn nnnnnnnn memory[N] 0 - 65535
|
|
*/
|
|
offset ++;
|
|
temp_data16 = buff[(operand_address + 1) & 0xffff] << 8;
|
|
temp_data16 = temp_data16 | buff[(operand_address + 2) & 0xffff];
|
|
/* debug
|
|
* g_warning("Reading 0x%x From address %u",temp_data16,operand_address);
|
|
*/
|
|
if ( (bytecode & 0x01) == 1 ){
|
|
memmory_addr = temp_data16;
|
|
temp_data16 = buff[memmory_addr] << 8;
|
|
temp_data16 = temp_data16 | buff[(memmory_addr+1) & 0xffff];
|
|
}
|
|
*value = temp_data16;
|
|
offset = offset +2;
|
|
}
|
|
|
|
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
|
|
case 3:
|
|
test_bits = ( bytecode & 0x20 ) >> 5;
|
|
if ( test_bits == 1 ){
|
|
/*
|
|
* 111nnnnn N + 65504 65504 - 65535
|
|
*/
|
|
operand = ( buff[operand_address] & 0x1f) + 65504;
|
|
*value = operand;
|
|
offset ++;
|
|
}else{
|
|
/*
|
|
* 110nnnnn nnnnnnnn memory[N] 0 - 65535
|
|
*/
|
|
memmory_addr = buff[operand_address] & 0x1f;
|
|
memmory_addr = memmory_addr << 8;
|
|
memmory_addr = memmory_addr | buff[(operand_address + 1) & 0xffff];
|
|
temp_data16 = buff[memmory_addr] << 8;
|
|
temp_data16 = temp_data16 | buff[(memmory_addr+1) & 0xffff];
|
|
*value = temp_data16;
|
|
/* debug
|
|
* g_warning("Reading 0x%x From address %u",temp_data16,memmory_addr);
|
|
*/
|
|
offset = offset +2;
|
|
}
|
|
|
|
default :
|
|
break;
|
|
}
|
|
return offset;
|
|
}
|
|
/*
|
|
*
|
|
* The fourth operand type is the address (@). This operand is decoded
|
|
* as a multitype operand followed by a further step: the memory address
|
|
* of the UDVM instruction containing the address operand is added to
|
|
* obtain the correct operand value. So if the operand value from
|
|
* Figure 10 is D then the actual operand value of an address is
|
|
* calculated as follows:
|
|
*
|
|
* operand_value = (memory_address_of_instruction + D) modulo 2^16
|
|
*
|
|
* Address operands are always used in instructions that control program
|
|
* flow, because they ensure that the UDVM bytecode is position-
|
|
* independent code (i.e., it will run independently of where it is
|
|
* placed in the UDVM memory).
|
|
*/
|
|
static int
|
|
decode_udvm_address_operand(guint8 *buff,guint operand_address, guint16 *value,guint current_address)
|
|
{
|
|
guint32 result;
|
|
guint16 value1;
|
|
guint next_opreand_address;
|
|
|
|
next_opreand_address = decode_udvm_multitype_operand(buff, operand_address, &value1);
|
|
result = value1 & 0xffff;
|
|
result = result + current_address;
|
|
*value = result & 0xffff;
|
|
return next_opreand_address;
|
|
}
|
|
|
|
|
|
/*
|
|
* This is a lookup table used to reverse the bits in a byte.
|
|
*/
|
|
static guint8 reverse [] = {
|
|
0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
|
|
0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
|
|
0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
|
|
0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
|
|
0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4,
|
|
0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
|
|
0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC,
|
|
0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
|
|
0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
|
|
0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
|
|
0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA,
|
|
0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
|
|
0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
|
|
0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
|
|
0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
|
|
0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
|
|
0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1,
|
|
0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
|
|
0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9,
|
|
0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
|
|
0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
|
|
0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
|
|
0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED,
|
|
0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
|
|
0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
|
|
0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
|
|
0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
|
|
0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
|
|
0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7,
|
|
0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
|
|
0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF,
|
|
0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
|
|
};
|
|
|
|
|
|
static int
|
|
decomp_dispatch_get_bits(
|
|
tvbuff_t *message_tvb,
|
|
proto_tree *udvm_tree,
|
|
guint8 bit_order,
|
|
guint8 *buff,
|
|
guint16 *old_input_bit_order,
|
|
guint16 *remaining_bits,
|
|
guint16 *input_bits,
|
|
guint *input_address,
|
|
guint16 length,
|
|
guint16 *result_code,
|
|
guint msg_end)
|
|
{
|
|
guint16 input_bit_order;
|
|
guint16 bits_still_required = length;
|
|
guint16 value = 0;
|
|
guint8 octet;
|
|
gint extra_bytes_available = msg_end - *input_address;
|
|
gint p_bit;
|
|
gint prev_p_bit = *old_input_bit_order & 0x0001;
|
|
gint bits_to_use = 0;
|
|
|
|
|
|
input_bit_order = buff[68] << 8;
|
|
input_bit_order = input_bit_order | buff[69];
|
|
*result_code = 0;
|
|
p_bit = (input_bit_order & 0x0001) != 0;
|
|
|
|
/*
|
|
* Discard any spare bits.
|
|
* Note: We take care to avoid remaining_bits having the value of 8.
|
|
*/
|
|
if (prev_p_bit != p_bit)
|
|
{
|
|
*remaining_bits = 0;
|
|
*old_input_bit_order = input_bit_order;
|
|
}
|
|
|
|
/*
|
|
* Check we can suppy the required number of bits now, before we alter
|
|
* the input buffer's state.
|
|
*/
|
|
if (*remaining_bits + extra_bytes_available * 8 < length)
|
|
{
|
|
*result_code = 11;
|
|
return 0xfbad;
|
|
}
|
|
|
|
/* Note: This is never called with length > 16, so the following loop
|
|
* never loops more than three time. */
|
|
while (bits_still_required > 0)
|
|
{
|
|
/*
|
|
* We only put anything into input_bits if we know we will remove
|
|
* at least one bit. That ensures we can simply discard the spare
|
|
* bits if the P-bit changes.
|
|
*/
|
|
if (*remaining_bits == 0)
|
|
{
|
|
octet = tvb_get_guint8(message_tvb, *input_address);
|
|
if (print_level_1 ){
|
|
proto_tree_add_text(udvm_tree, message_tvb, *input_address , 1,
|
|
" Getting value: %u (0x%x) From Addr: %u", octet, octet, *input_address);
|
|
}
|
|
*input_address = *input_address + 1;
|
|
|
|
if (p_bit != 0)
|
|
{
|
|
octet = reverse[octet];
|
|
}
|
|
*input_bits = octet;
|
|
*remaining_bits = 8;
|
|
}
|
|
|
|
/* Add some more bits to the accumulated value. */
|
|
bits_to_use = bits_still_required < *remaining_bits ? bits_still_required : *remaining_bits;
|
|
bits_still_required -= bits_to_use;
|
|
|
|
*input_bits <<= bits_to_use; /* Shift bits into MSByte */
|
|
value = (value << bits_to_use) /* Then add to the accumulated value */
|
|
| ((*input_bits >> 8) & 0xFF);
|
|
*remaining_bits -= bits_to_use;
|
|
*input_bits &= 0x00FF; /* Leave just the remaining bits */
|
|
}
|
|
|
|
if (bit_order != 0)
|
|
{
|
|
/* Bit reverse the entire word. */
|
|
guint16 lsb = reverse[(value >> 8) & 0xFF];
|
|
guint16 msb = reverse[value & 0xFF];
|
|
|
|
value = ((msb << 8) | lsb) >> (16 - length);
|
|
}
|
|
|
|
return value;
|
|
}
|
|
|
|
|
|
/* end udvm */
|
|
|