![Martin Kaiser](/assets/img/avatar_default.png)
tvb_get_ephemeral_unicode_string(), throw an exception for invalid lengths (including -1, but length==-1 does not work for other tvb string functions either) I believe this is the proper fix for https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=8112 svn path=/trunk/; revision=46705
3647 lines
92 KiB
C
3647 lines
92 KiB
C
/* tvbuff.c
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*
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* Testy, Virtual(-izable) Buffer of guint8*'s
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*
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* "Testy" -- the buffer gets mad when an attempt to access data
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* beyond the bounds of the buffer. An exception is thrown.
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*
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* "Virtual" -- the buffer can have its own data, can use a subset of
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* the data of a backing tvbuff, or can be a composite of
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* other tvbuffs.
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*
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* $Id$
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*
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* Copyright (c) 2000 by Gilbert Ramirez <gram@alumni.rice.edu>
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*
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* Code to convert IEEE floating point formats to native floating point
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* derived from code Copyright (c) Ashok Narayanan, 2000
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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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*/
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#include "config.h"
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#include <string.h>
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#ifdef HAVE_LIBZ
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#include <zlib.h>
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#endif
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#include "pint.h"
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#include "tvbuff.h"
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#include "tvbuff-int.h"
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#include "strutil.h"
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#include "emem.h"
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#include "charsets.h"
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#include "proto.h" /* XXX - only used for DISSECTOR_ASSERT, probably a new header file? */
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static const guint8*
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ensure_contiguous_no_exception(tvbuff_t *tvb, const gint offset, const gint length,
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int *exception);
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static const guint8*
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ensure_contiguous(tvbuff_t *tvb, const gint offset, const gint length);
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static guint64
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_tvb_get_bits64(tvbuff_t *tvb, guint bit_offset, const gint total_no_of_bits);
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static void
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tvb_init(tvbuff_t *tvb, const tvbuff_type type)
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{
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tvb_backing_t *backing;
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tvb_comp_t *composite;
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tvb->previous = NULL;
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tvb->next = NULL;
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tvb->type = type;
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tvb->initialized = FALSE;
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tvb->length = 0;
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tvb->reported_length = 0;
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tvb->free_cb = NULL;
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tvb->real_data = NULL;
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tvb->raw_offset = -1;
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tvb->ds_tvb = NULL;
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switch(type) {
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case TVBUFF_REAL_DATA:
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/* Nothing */
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break;
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case TVBUFF_SUBSET:
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backing = &tvb->tvbuffs.subset;
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backing->tvb = NULL;
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backing->offset = 0;
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backing->length = 0;
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break;
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case TVBUFF_COMPOSITE:
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composite = &tvb->tvbuffs.composite;
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composite->tvbs = NULL;
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composite->start_offsets = NULL;
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composite->end_offsets = NULL;
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break;
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default:
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DISSECTOR_ASSERT_NOT_REACHED();
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break;
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}
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}
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tvbuff_t *
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tvb_new(const tvbuff_type type)
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{
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tvbuff_t *tvb;
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tvb = g_slice_new(tvbuff_t);
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tvb_init(tvb, type);
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return tvb;
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}
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static tvbuff_t *
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tvb_new_with_subset(const guint subset_tvb_offset, const guint subset_tvb_length)
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{
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tvbuff_t *tvb = tvb_new(TVBUFF_SUBSET);
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tvb->tvbuffs.subset.offset = subset_tvb_offset;
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tvb->tvbuffs.subset.length = subset_tvb_length;
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return tvb;
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}
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static void
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tvb_free_internal(tvbuff_t *tvb)
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{
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tvb_comp_t *composite;
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DISSECTOR_ASSERT(tvb);
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switch (tvb->type) {
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case TVBUFF_REAL_DATA:
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if (tvb->free_cb) {
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/*
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* XXX - do this with a union?
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*/
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tvb->free_cb((gpointer)tvb->real_data);
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}
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break;
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case TVBUFF_SUBSET:
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/* Nothing */
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break;
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case TVBUFF_COMPOSITE:
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composite = &tvb->tvbuffs.composite;
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g_slist_free(composite->tvbs);
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g_free(composite->start_offsets);
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g_free(composite->end_offsets);
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if (tvb->real_data) {
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/*
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* XXX - do this with a union?
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*/
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g_free((gpointer)tvb->real_data);
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}
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break;
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default:
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DISSECTOR_ASSERT_NOT_REACHED();
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}
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g_slice_free(tvbuff_t, tvb);
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}
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/* XXX: just call tvb_free_chain();
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* Not removed so that existing dissectors using tvb_free() need not be changed.
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* I'd argue that existing calls to tvb_free() should have actually beeen
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* calls to tvb_free_chain() although the calls were OK as long as no
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* subsets, etc had been created on the tvb. */
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void
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tvb_free(tvbuff_t *tvb)
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{
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tvb_free_chain(tvb);
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}
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void
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tvb_free_chain(tvbuff_t *tvb)
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{
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tvbuff_t *next_tvb;
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DISSECTOR_ASSERT(tvb);
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DISSECTOR_ASSERT_HINT(tvb->previous==NULL, "tvb_free_chain(): tvb must be initial tvb in chain");
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while (tvb) {
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next_tvb=tvb->next;
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DISSECTOR_ASSERT_HINT((next_tvb==NULL) || (tvb==next_tvb->previous), "tvb_free_chain(): corrupt tvb chain ?");
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tvb_free_internal(tvb);
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tvb = next_tvb;
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}
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}
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void
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tvb_set_free_cb(tvbuff_t *tvb, const tvbuff_free_cb_t func)
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{
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DISSECTOR_ASSERT(tvb);
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DISSECTOR_ASSERT(tvb->type == TVBUFF_REAL_DATA);
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tvb->free_cb = func;
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}
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static void
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add_to_chain(tvbuff_t *parent, tvbuff_t *child)
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{
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DISSECTOR_ASSERT(parent && child);
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DISSECTOR_ASSERT(!child->next && !child->previous);
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child->next = parent->next;
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child->previous = parent;
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if (parent->next)
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parent->next->previous = child;
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parent->next = child;
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}
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void
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tvb_set_child_real_data_tvbuff(tvbuff_t *parent, tvbuff_t *child)
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{
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DISSECTOR_ASSERT(parent && child);
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DISSECTOR_ASSERT(parent->initialized);
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DISSECTOR_ASSERT(child->initialized);
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DISSECTOR_ASSERT(child->type == TVBUFF_REAL_DATA);
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add_to_chain(parent, child);
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}
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static void
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tvb_set_real_data_no_exceptions(tvbuff_t *tvb, const guint8* data, const guint length, const gint reported_length)
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{
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tvb->real_data = data;
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tvb->length = length;
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tvb->reported_length = reported_length;
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tvb->initialized = TRUE;
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}
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void
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tvb_set_real_data(tvbuff_t *tvb, const guint8* data, const guint length, const gint reported_length)
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{
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DISSECTOR_ASSERT(tvb);
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DISSECTOR_ASSERT(tvb->type == TVBUFF_REAL_DATA);
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DISSECTOR_ASSERT(!tvb->initialized);
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THROW_ON(reported_length < -1, ReportedBoundsError);
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tvb_set_real_data_no_exceptions(tvb, data, length, reported_length);
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}
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tvbuff_t *
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tvb_new_real_data(const guint8* data, const guint length, const gint reported_length)
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{
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tvbuff_t *tvb;
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THROW_ON(reported_length < -1, ReportedBoundsError);
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tvb = tvb_new(TVBUFF_REAL_DATA);
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tvb_set_real_data_no_exceptions(tvb, data, length, reported_length);
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/*
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* This is the top-level real tvbuff for this data source,
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* so its data source tvbuff is itself.
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*/
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tvb->ds_tvb = tvb;
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return tvb;
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}
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tvbuff_t *
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tvb_new_child_real_data(tvbuff_t *parent, const guint8* data, const guint length, const gint reported_length)
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{
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tvbuff_t *tvb = tvb_new_real_data(data, length, reported_length);
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if (tvb) {
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tvb_set_child_real_data_tvbuff (parent, tvb);
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}
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return tvb;
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}
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static const unsigned char left_aligned_bitmask[] = {
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0xff,
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0x80,
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0xc0,
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0xe0,
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0xf0,
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0xf8,
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0xfc,
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0xfe
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};
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tvbuff_t *
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tvb_new_octet_aligned(tvbuff_t *tvb, guint32 bit_offset, gint32 no_of_bits)
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{
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tvbuff_t *sub_tvb = NULL;
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guint32 byte_offset;
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gint32 datalen, i;
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guint8 left, right, remaining_bits, *buf;
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const guint8 *data;
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byte_offset = bit_offset >> 3;
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left = bit_offset % 8; /* for left-shifting */
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right = 8 - left; /* for right-shifting */
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if (no_of_bits == -1) {
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datalen = tvb_length_remaining(tvb, byte_offset);
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remaining_bits = 0;
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} else {
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datalen = no_of_bits >> 3;
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remaining_bits = no_of_bits % 8;
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if (remaining_bits) {
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datalen++;
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}
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}
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/* already aligned -> shortcut */
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if ((left == 0) && (remaining_bits == 0)) {
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return tvb_new_subset(tvb, byte_offset, datalen, -1);
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}
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DISSECTOR_ASSERT(datalen>0);
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buf = ep_alloc0(datalen);
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/* if at least one trailing byte is available, we must use the content
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* of that byte for the last shift (i.e. tvb_get_ptr() must use datalen + 1
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* if non extra byte is available, the last shifted byte requires
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* special treatment
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*/
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if (tvb_length_remaining(tvb, byte_offset) > datalen) {
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data = tvb_get_ptr(tvb, byte_offset, datalen + 1);
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/* shift tvb data bit_offset bits to the left */
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for (i = 0; i < datalen; i++)
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buf[i] = (data[i] << left) | (data[i+1] >> right);
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} else {
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data = tvb_get_ptr(tvb, byte_offset, datalen);
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/* shift tvb data bit_offset bits to the left */
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for (i = 0; i < (datalen-1); i++)
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buf[i] = (data[i] << left) | (data[i+1] >> right);
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buf[datalen-1] = data[datalen-1] << left; /* set last octet */
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}
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buf[datalen-1] &= left_aligned_bitmask[remaining_bits];
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sub_tvb = tvb_new_child_real_data(tvb, buf, datalen, datalen);
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return sub_tvb;
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}
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/* Computes the absolute offset and length based on a possibly-negative offset
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* and a length that is possible -1 (which means "to the end of the data").
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* Returns TRUE/FALSE indicating whether the offset is in bounds or
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* not. The integer ptrs are modified with the new offset and length.
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* No exception is thrown.
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*
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* XXX - we return TRUE, not FALSE, if the offset is positive and right
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* after the end of the tvbuff (i.e., equal to the length). We do this
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* so that a dissector constructing a subset tvbuff for the next protocol
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* will get a zero-length tvbuff, not an exception, if there's no data
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* left for the next protocol - we want the next protocol to be the one
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* that gets an exception, so the error is reported as an error in that
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* protocol rather than the containing protocol. */
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static gboolean
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compute_offset_length(const guint tvb_length_val, const guint tvb_reported_length_val,
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const gint offset, const gint length_val,
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guint *offset_ptr, guint *length_ptr, int *exception)
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{
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DISSECTOR_ASSERT(offset_ptr);
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DISSECTOR_ASSERT(length_ptr);
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/* Compute the offset */
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if (offset >= 0) {
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/* Positive offset - relative to the beginning of the packet. */
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if ((guint) offset > tvb_reported_length_val) {
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if (exception) {
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*exception = ReportedBoundsError;
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}
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return FALSE;
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}
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else if ((guint) offset > tvb_length_val) {
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if (exception) {
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*exception = BoundsError;
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}
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return FALSE;
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}
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else {
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*offset_ptr = offset;
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}
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}
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else {
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/* Negative offset - relative to the end of the packet. */
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if ((guint) -offset > tvb_reported_length_val) {
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if (exception) {
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*exception = ReportedBoundsError;
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}
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return FALSE;
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}
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else if ((guint) -offset > tvb_length_val) {
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if (exception) {
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*exception = BoundsError;
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}
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return FALSE;
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}
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else {
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*offset_ptr = tvb_length_val + offset;
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}
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}
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/* Compute the length */
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if (length_val < -1) {
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if (exception) {
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/* XXX - ReportedBoundsError? */
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*exception = BoundsError;
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}
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return FALSE;
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}
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else if (length_val == -1) {
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*length_ptr = tvb_length_val - *offset_ptr;
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}
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else {
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*length_ptr = length_val;
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}
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return TRUE;
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}
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static gboolean
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check_offset_length_no_exception(const guint tvb_length_val, const guint tvb_reported_length_val,
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const gint offset, gint const length_val,
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guint *offset_ptr, guint *length_ptr, int *exception)
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{
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guint end_offset;
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if (!compute_offset_length(tvb_length_val, tvb_reported_length_val,
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offset, length_val, offset_ptr, length_ptr, exception)) {
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return FALSE;
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}
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/*
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* Compute the offset of the first byte past the length.
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*/
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end_offset = *offset_ptr + *length_ptr;
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/*
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* Check for an overflow, and clamp "end_offset" at the maximum
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* if we got an overflow - that should force us to indicate that
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* we're past the end of the tvbuff.
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*/
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if (end_offset < *offset_ptr)
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end_offset = UINT_MAX;
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/*
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* Check whether that offset goes more than one byte past the
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* end of the buffer.
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*
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* If not, return TRUE; otherwise, return FALSE and, if "exception"
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* is non-null, return the appropriate exception through it.
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*/
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if (end_offset <= tvb_length_val) {
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return TRUE;
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}
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else if (end_offset <= tvb_reported_length_val) {
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if (exception) {
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*exception = BoundsError;
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}
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}
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else {
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if (exception) {
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*exception = ReportedBoundsError;
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}
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}
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|
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return FALSE;
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}
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|
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/* Checks (+/-) offset and length and throws an exception if
|
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* either is out of bounds. Sets integer ptrs to the new offset
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* and length. */
|
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static void
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check_offset_length(const guint tvb_length_val, const guint tvb_reported_length_val,
|
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const gint offset, gint const length_val,
|
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guint *offset_ptr, guint *length_ptr)
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{
|
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int exception = 0;
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|
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if (!check_offset_length_no_exception(tvb_length_val, tvb_reported_length_val,
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offset, length_val, offset_ptr, length_ptr, &exception)) {
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DISSECTOR_ASSERT(exception > 0);
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THROW(exception);
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}
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}
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|
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static void
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tvb_set_subset_no_exceptions(tvbuff_t *tvb, tvbuff_t *backing, const gint reported_length)
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{
|
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tvb->tvbuffs.subset.tvb = backing;
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tvb->length = tvb->tvbuffs.subset.length;
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|
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if (reported_length == -1) {
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tvb->reported_length = backing->reported_length - tvb->tvbuffs.subset.offset;
|
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}
|
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else {
|
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tvb->reported_length = reported_length;
|
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}
|
|
tvb->initialized = TRUE;
|
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add_to_chain(backing, tvb);
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|
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/* Optimization. If the backing buffer has a pointer to contiguous, real data,
|
|
* then we can point directly to our starting offset in that buffer */
|
|
if (backing->real_data != NULL) {
|
|
tvb->real_data = backing->real_data + tvb->tvbuffs.subset.offset;
|
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}
|
|
}
|
|
|
|
void
|
|
tvb_set_subset(tvbuff_t *tvb, tvbuff_t *backing,
|
|
const gint backing_offset, const gint backing_length, const gint reported_length)
|
|
{
|
|
DISSECTOR_ASSERT(tvb);
|
|
DISSECTOR_ASSERT(tvb->type == TVBUFF_SUBSET);
|
|
DISSECTOR_ASSERT(!tvb->initialized);
|
|
|
|
THROW_ON(reported_length < -1, ReportedBoundsError);
|
|
|
|
check_offset_length(backing->length, backing->reported_length, backing_offset, backing_length,
|
|
&tvb->tvbuffs.subset.offset,
|
|
&tvb->tvbuffs.subset.length);
|
|
|
|
tvb_set_subset_no_exceptions(tvb, backing, reported_length);
|
|
}
|
|
|
|
tvbuff_t *
|
|
tvb_new_subset(tvbuff_t *backing, const gint backing_offset, const gint backing_length, const gint reported_length)
|
|
{
|
|
tvbuff_t *tvb;
|
|
guint subset_tvb_offset;
|
|
guint subset_tvb_length;
|
|
|
|
DISSECTOR_ASSERT(backing && backing->initialized);
|
|
|
|
THROW_ON(reported_length < -1, ReportedBoundsError);
|
|
|
|
check_offset_length(backing->length, backing->reported_length, backing_offset, backing_length,
|
|
&subset_tvb_offset,
|
|
&subset_tvb_length);
|
|
|
|
tvb = tvb_new_with_subset(subset_tvb_offset, subset_tvb_length);
|
|
|
|
tvb_set_subset_no_exceptions(tvb, backing, reported_length);
|
|
|
|
/*
|
|
* The top-level data source of this tvbuff is the top-level
|
|
* data source of its parent.
|
|
*/
|
|
tvb->ds_tvb = backing->ds_tvb;
|
|
|
|
return tvb;
|
|
}
|
|
|
|
tvbuff_t *
|
|
tvb_new_subset_remaining(tvbuff_t *backing, const gint backing_offset)
|
|
{
|
|
tvbuff_t *tvb;
|
|
guint subset_tvb_offset;
|
|
guint subset_tvb_length;
|
|
|
|
check_offset_length(backing->length, backing->reported_length, backing_offset, -1 /* backing_length */,
|
|
&subset_tvb_offset,
|
|
&subset_tvb_length);
|
|
|
|
tvb = tvb_new_with_subset(subset_tvb_offset, subset_tvb_length);
|
|
|
|
tvb_set_subset_no_exceptions(tvb, backing, -1 /* reported_length */);
|
|
|
|
/*
|
|
* The top-level data source of this tvbuff is the top-level
|
|
* data source of its parent.
|
|
*/
|
|
tvb->ds_tvb = backing->ds_tvb;
|
|
|
|
return tvb;
|
|
}
|
|
|
|
/*
|
|
* Composite tvb
|
|
*
|
|
* 1. A composite tvb is automatically chained to its first member when the
|
|
* tvb is finalized.
|
|
* This means that composite tvb members must all be in the same chain.
|
|
* ToDo: enforce this: By searching the chain?
|
|
*/
|
|
tvbuff_t *
|
|
tvb_new_composite(void)
|
|
{
|
|
return tvb_new(TVBUFF_COMPOSITE);
|
|
}
|
|
|
|
void
|
|
tvb_composite_append(tvbuff_t *tvb, tvbuff_t *member)
|
|
{
|
|
tvb_comp_t *composite;
|
|
|
|
DISSECTOR_ASSERT(tvb && !tvb->initialized);
|
|
DISSECTOR_ASSERT(tvb->type == TVBUFF_COMPOSITE);
|
|
|
|
/* Don't allow zero-length TVBs: composite_memcpy() can't handle them
|
|
* and anyway it makes no sense.
|
|
*/
|
|
DISSECTOR_ASSERT(member->length);
|
|
|
|
composite = &tvb->tvbuffs.composite;
|
|
composite->tvbs = g_slist_append(composite->tvbs, member);
|
|
}
|
|
|
|
void
|
|
tvb_composite_prepend(tvbuff_t *tvb, tvbuff_t *member)
|
|
{
|
|
tvb_comp_t *composite;
|
|
|
|
DISSECTOR_ASSERT(tvb && !tvb->initialized);
|
|
DISSECTOR_ASSERT(tvb->type == TVBUFF_COMPOSITE);
|
|
|
|
/* Don't allow zero-length TVBs: composite_memcpy() can't handle them
|
|
* and anyway it makes no sense.
|
|
*/
|
|
DISSECTOR_ASSERT(member->length);
|
|
|
|
composite = &tvb->tvbuffs.composite;
|
|
composite->tvbs = g_slist_prepend(composite->tvbs, member);
|
|
}
|
|
|
|
|
|
void
|
|
tvb_composite_finalize(tvbuff_t *tvb)
|
|
{
|
|
GSList *slist;
|
|
guint num_members;
|
|
tvbuff_t *member_tvb;
|
|
tvb_comp_t *composite;
|
|
int i = 0;
|
|
|
|
DISSECTOR_ASSERT(tvb && !tvb->initialized);
|
|
DISSECTOR_ASSERT(tvb->type == TVBUFF_COMPOSITE);
|
|
DISSECTOR_ASSERT(tvb->length == 0);
|
|
DISSECTOR_ASSERT(tvb->reported_length == 0);
|
|
|
|
composite = &tvb->tvbuffs.composite;
|
|
num_members = g_slist_length(composite->tvbs);
|
|
|
|
/* Dissectors should not create composite TVBs if they're not going to
|
|
* put at least one TVB in them.
|
|
* (Without this check--or something similar--we'll seg-fault below.)
|
|
*/
|
|
DISSECTOR_ASSERT(num_members);
|
|
|
|
composite->start_offsets = g_new(guint, num_members);
|
|
composite->end_offsets = g_new(guint, num_members);
|
|
|
|
for (slist = composite->tvbs; slist != NULL; slist = slist->next) {
|
|
DISSECTOR_ASSERT((guint) i < num_members);
|
|
member_tvb = slist->data;
|
|
composite->start_offsets[i] = tvb->length;
|
|
tvb->length += member_tvb->length;
|
|
tvb->reported_length += member_tvb->reported_length;
|
|
composite->end_offsets[i] = tvb->length - 1;
|
|
i++;
|
|
}
|
|
add_to_chain((tvbuff_t *)composite->tvbs->data, tvb); /* chain composite tvb to first member */
|
|
tvb->initialized = TRUE;
|
|
}
|
|
|
|
|
|
|
|
guint
|
|
tvb_length(const tvbuff_t *tvb)
|
|
{
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
return tvb->length;
|
|
}
|
|
|
|
gint
|
|
tvb_length_remaining(const tvbuff_t *tvb, const gint offset)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
if (compute_offset_length(tvb->length, tvb->reported_length, offset, -1, &abs_offset, &abs_length, NULL)) {
|
|
return abs_length;
|
|
}
|
|
else {
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
guint
|
|
tvb_ensure_length_remaining(const tvbuff_t *tvb, const gint offset)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
int exception;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
if (!compute_offset_length(tvb->length, tvb->reported_length, offset, -1, &abs_offset, &abs_length, &exception)) {
|
|
THROW(exception);
|
|
}
|
|
if (abs_length == 0) {
|
|
/*
|
|
* This routine ensures there's at least one byte available.
|
|
* There aren't any bytes available, so throw the appropriate
|
|
* exception.
|
|
*/
|
|
if (abs_offset >= tvb->reported_length)
|
|
THROW(ReportedBoundsError);
|
|
else
|
|
THROW(BoundsError);
|
|
}
|
|
return abs_length;
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Validates that 'length' bytes are available starting from
|
|
* offset (pos/neg). Does not throw an exception. */
|
|
gboolean
|
|
tvb_bytes_exist(const tvbuff_t *tvb, const gint offset, const gint length)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
if (!compute_offset_length(tvb->length, tvb->reported_length, offset, length, &abs_offset, &abs_length, NULL))
|
|
return FALSE;
|
|
|
|
if (abs_offset + abs_length <= tvb->length) {
|
|
return TRUE;
|
|
}
|
|
else {
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
/* Validates that 'length' bytes are available starting from
|
|
* offset (pos/neg). Throws an exception if they aren't. */
|
|
void
|
|
tvb_ensure_bytes_exist(const tvbuff_t *tvb, const gint offset, const gint length)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
/*
|
|
* -1 doesn't mean "until end of buffer", as that's pointless
|
|
* for this routine. We must treat it as a Really Large Positive
|
|
* Number, so that we throw an exception; we throw
|
|
* ReportedBoundsError, as if it were past even the end of a
|
|
* reassembled packet, and past the end of even the data we
|
|
* didn't capture.
|
|
*
|
|
* We do the same with other negative lengths.
|
|
*/
|
|
if (length < 0) {
|
|
THROW(ReportedBoundsError);
|
|
}
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, length, &abs_offset, &abs_length);
|
|
}
|
|
|
|
gboolean
|
|
tvb_offset_exists(const tvbuff_t *tvb, const gint offset)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
if (!compute_offset_length(tvb->length, tvb->reported_length, offset, -1, &abs_offset, &abs_length, NULL))
|
|
return FALSE;
|
|
|
|
if (abs_offset < tvb->length) {
|
|
return TRUE;
|
|
}
|
|
else {
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
guint
|
|
tvb_reported_length(const tvbuff_t *tvb)
|
|
{
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
return tvb->reported_length;
|
|
}
|
|
|
|
gint
|
|
tvb_reported_length_remaining(const tvbuff_t *tvb, const gint offset)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
if (compute_offset_length(tvb->length, tvb->reported_length, offset, -1, &abs_offset, &abs_length, NULL)) {
|
|
if (tvb->reported_length >= abs_offset)
|
|
return tvb->reported_length - abs_offset;
|
|
else
|
|
return -1;
|
|
}
|
|
else {
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* Set the reported length of a tvbuff to a given value; used for protocols
|
|
* whose headers contain an explicit length and where the calling
|
|
* dissector's payload may include padding as well as the packet for
|
|
* this protocol.
|
|
* Also adjusts the data length. */
|
|
void
|
|
tvb_set_reported_length(tvbuff_t *tvb, const guint reported_length)
|
|
{
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
if (reported_length > tvb->reported_length)
|
|
THROW(ReportedBoundsError);
|
|
|
|
tvb->reported_length = reported_length;
|
|
if (reported_length < tvb->length)
|
|
tvb->length = reported_length;
|
|
}
|
|
|
|
|
|
#if 0
|
|
static const guint8*
|
|
first_real_data_ptr(tvbuff_t *tvb)
|
|
{
|
|
tvbuff_t *member;
|
|
|
|
switch(tvb->type) {
|
|
case TVBUFF_REAL_DATA:
|
|
return tvb->real_data;
|
|
case TVBUFF_SUBSET:
|
|
member = tvb->tvbuffs.subset.tvb;
|
|
return first_real_data_ptr(member);
|
|
case TVBUFF_COMPOSITE:
|
|
member = tvb->tvbuffs.composite.tvbs->data;
|
|
return first_real_data_ptr(member);
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
static guint
|
|
offset_from_real_beginning(const tvbuff_t *tvb, const guint counter)
|
|
{
|
|
tvbuff_t *member;
|
|
|
|
switch(tvb->type) {
|
|
case TVBUFF_REAL_DATA:
|
|
return counter;
|
|
case TVBUFF_SUBSET:
|
|
member = tvb->tvbuffs.subset.tvb;
|
|
return offset_from_real_beginning(member, counter + tvb->tvbuffs.subset.offset);
|
|
case TVBUFF_COMPOSITE:
|
|
member = tvb->tvbuffs.composite.tvbs->data;
|
|
return offset_from_real_beginning(member, counter);
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
return 0;
|
|
}
|
|
|
|
guint
|
|
tvb_offset_from_real_beginning(const tvbuff_t *tvb)
|
|
{
|
|
return offset_from_real_beginning(tvb, 0);
|
|
}
|
|
|
|
static const guint8*
|
|
composite_ensure_contiguous_no_exception(tvbuff_t *tvb, const guint abs_offset, const guint abs_length)
|
|
{
|
|
guint i, num_members;
|
|
tvb_comp_t *composite;
|
|
tvbuff_t *member_tvb = NULL;
|
|
guint member_offset, member_length;
|
|
GSList *slist;
|
|
|
|
DISSECTOR_ASSERT(tvb->type == TVBUFF_COMPOSITE);
|
|
|
|
/* Maybe the range specified by offset/length
|
|
* is contiguous inside one of the member tvbuffs */
|
|
composite = &tvb->tvbuffs.composite;
|
|
num_members = g_slist_length(composite->tvbs);
|
|
|
|
for (i = 0; i < num_members; i++) {
|
|
if (abs_offset <= composite->end_offsets[i]) {
|
|
slist = g_slist_nth(composite->tvbs, i);
|
|
member_tvb = slist->data;
|
|
break;
|
|
}
|
|
}
|
|
DISSECTOR_ASSERT(member_tvb);
|
|
|
|
if (check_offset_length_no_exception(member_tvb->length, member_tvb->reported_length,
|
|
abs_offset - composite->start_offsets[i],
|
|
abs_length, &member_offset, &member_length, NULL)) {
|
|
|
|
/*
|
|
* The range is, in fact, contiguous within member_tvb.
|
|
*/
|
|
DISSECTOR_ASSERT(!tvb->real_data);
|
|
return ensure_contiguous_no_exception(member_tvb, member_offset, member_length, NULL);
|
|
}
|
|
else {
|
|
tvb->real_data = tvb_memdup(tvb, 0, -1);
|
|
return tvb->real_data + abs_offset;
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
static const guint8*
|
|
ensure_contiguous_no_exception(tvbuff_t *tvb, const gint offset, const gint length, int *exception)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
|
|
if (!check_offset_length_no_exception(tvb->length, tvb->reported_length, offset, length,
|
|
&abs_offset, &abs_length, exception)) {
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* We know that all the data is present in the tvbuff, so
|
|
* no exceptions should be thrown.
|
|
*/
|
|
if (tvb->real_data) {
|
|
return tvb->real_data + abs_offset;
|
|
}
|
|
else {
|
|
switch(tvb->type) {
|
|
case TVBUFF_REAL_DATA:
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
case TVBUFF_SUBSET:
|
|
return ensure_contiguous_no_exception(tvb->tvbuffs.subset.tvb,
|
|
abs_offset - tvb->tvbuffs.subset.offset,
|
|
abs_length, NULL);
|
|
case TVBUFF_COMPOSITE:
|
|
return composite_ensure_contiguous_no_exception(tvb, abs_offset, abs_length);
|
|
}
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
return NULL;
|
|
}
|
|
|
|
static const guint8*
|
|
ensure_contiguous(tvbuff_t *tvb, const gint offset, const gint length)
|
|
{
|
|
int exception = 0;
|
|
const guint8 *p;
|
|
|
|
p = ensure_contiguous_no_exception(tvb, offset, length, &exception);
|
|
if (p == NULL) {
|
|
DISSECTOR_ASSERT(exception > 0);
|
|
THROW(exception);
|
|
}
|
|
return p;
|
|
}
|
|
|
|
static const guint8*
|
|
fast_ensure_contiguous(tvbuff_t *tvb, const gint offset, const guint length)
|
|
{
|
|
guint end_offset;
|
|
guint u_offset;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
/* We don't check for overflow in this fast path so we only handle simple types */
|
|
DISSECTOR_ASSERT(length <= 8);
|
|
|
|
if (offset < 0 || !tvb->real_data) {
|
|
return ensure_contiguous(tvb, offset, length);
|
|
}
|
|
|
|
u_offset = offset;
|
|
end_offset = u_offset + length;
|
|
|
|
if (end_offset <= tvb->length) {
|
|
return tvb->real_data + u_offset;
|
|
}
|
|
|
|
if (end_offset > tvb->reported_length) {
|
|
THROW(ReportedBoundsError);
|
|
}
|
|
THROW(BoundsError);
|
|
/* not reached */
|
|
return NULL;
|
|
}
|
|
|
|
static const guint8*
|
|
guint8_pbrk(const guint8* haystack, size_t haystacklen, const guint8 *needles, guchar *found_needle)
|
|
{
|
|
gchar tmp[256] = { 0 };
|
|
const guint8 *haystack_end;
|
|
|
|
while (*needles)
|
|
tmp[*needles++] = 1;
|
|
|
|
haystack_end = haystack + haystacklen;
|
|
while (haystack < haystack_end) {
|
|
if (tmp[*haystack]) {
|
|
if (found_needle)
|
|
*found_needle = *haystack;
|
|
return haystack;
|
|
}
|
|
haystack++;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
|
|
|
|
/************** ACCESSORS **************/
|
|
|
|
static void *
|
|
composite_memcpy(tvbuff_t *tvb, guint8* target, guint abs_offset, size_t abs_length)
|
|
{
|
|
guint i, num_members;
|
|
tvb_comp_t *composite;
|
|
tvbuff_t *member_tvb = NULL;
|
|
guint member_offset, member_length;
|
|
gboolean retval;
|
|
GSList *slist;
|
|
|
|
DISSECTOR_ASSERT(tvb->type == TVBUFF_COMPOSITE);
|
|
|
|
/* Maybe the range specified by offset/length
|
|
* is contiguous inside one of the member tvbuffs */
|
|
composite = &tvb->tvbuffs.composite;
|
|
num_members = g_slist_length(composite->tvbs);
|
|
|
|
for (i = 0; i < num_members; i++) {
|
|
if (abs_offset <= composite->end_offsets[i]) {
|
|
slist = g_slist_nth(composite->tvbs, i);
|
|
member_tvb = slist->data;
|
|
break;
|
|
}
|
|
}
|
|
DISSECTOR_ASSERT(member_tvb);
|
|
|
|
if (check_offset_length_no_exception(member_tvb->length, member_tvb->reported_length, abs_offset - composite->start_offsets[i],
|
|
(gint) abs_length, &member_offset, &member_length, NULL)) {
|
|
|
|
DISSECTOR_ASSERT(!tvb->real_data);
|
|
return tvb_memcpy(member_tvb, target, member_offset, member_length);
|
|
}
|
|
else {
|
|
/* The requested data is non-contiguous inside
|
|
* the member tvb. We have to memcpy() the part that's in the member tvb,
|
|
* then iterate across the other member tvb's, copying their portions
|
|
* until we have copied all data.
|
|
*/
|
|
retval = compute_offset_length(member_tvb->length, member_tvb->reported_length, abs_offset - composite->start_offsets[i], -1,
|
|
&member_offset, &member_length, NULL);
|
|
DISSECTOR_ASSERT(retval);
|
|
|
|
/* composite_memcpy() can't handle a member_length of zero. */
|
|
DISSECTOR_ASSERT(member_length);
|
|
|
|
tvb_memcpy(member_tvb, target, member_offset, member_length);
|
|
abs_offset += member_length;
|
|
abs_length -= member_length;
|
|
|
|
/* Recurse */
|
|
if (abs_length > 0) {
|
|
composite_memcpy(tvb, target + member_length, abs_offset, abs_length);
|
|
}
|
|
|
|
return target;
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
void *
|
|
tvb_memcpy(tvbuff_t *tvb, void *target, const gint offset, size_t length)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
/*
|
|
* XXX - we should eliminate the "length = -1 means 'to the end
|
|
* of the tvbuff'" convention, and use other means to achieve
|
|
* that; this would let us eliminate a bunch of checks for
|
|
* negative lengths in cases where the protocol has a 32-bit
|
|
* length field.
|
|
*
|
|
* Allowing -1 but throwing an assertion on other negative
|
|
* lengths is a bit more work with the length being a size_t;
|
|
* instead, we check for a length <= 2^31-1.
|
|
*/
|
|
DISSECTOR_ASSERT(length <= 0x7FFFFFFF);
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, (gint) length, &abs_offset, &abs_length);
|
|
|
|
if (tvb->real_data) {
|
|
return memcpy(target, tvb->real_data + abs_offset, abs_length);
|
|
}
|
|
|
|
switch(tvb->type) {
|
|
case TVBUFF_REAL_DATA:
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
|
|
case TVBUFF_SUBSET:
|
|
return tvb_memcpy(tvb->tvbuffs.subset.tvb, target,
|
|
abs_offset - tvb->tvbuffs.subset.offset,
|
|
abs_length);
|
|
|
|
case TVBUFF_COMPOSITE:
|
|
return composite_memcpy(tvb, target, offset, length);
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/*
|
|
* XXX - this doesn't treat a length of -1 as an error.
|
|
* If it did, this could replace some code that calls
|
|
* "tvb_ensure_bytes_exist()" and then allocates a buffer and copies
|
|
* data to it.
|
|
*
|
|
* "composite_ensure_contiguous_no_exception()" depends on -1 not being
|
|
* an error; does anything else depend on this routine treating -1 as
|
|
* meaning "to the end of the buffer"?
|
|
*/
|
|
void *
|
|
tvb_memdup(tvbuff_t *tvb, const gint offset, size_t length)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
void *duped;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, (gint) length, &abs_offset, &abs_length);
|
|
|
|
duped = g_malloc(abs_length);
|
|
return tvb_memcpy(tvb, duped, abs_offset, abs_length);
|
|
}
|
|
|
|
/*
|
|
* XXX - this doesn't treat a length of -1 as an error.
|
|
* If it did, this could replace some code that calls
|
|
* "tvb_ensure_bytes_exist()" and then allocates a buffer and copies
|
|
* data to it.
|
|
*
|
|
* "composite_ensure_contiguous_no_exception()" depends on -1 not being
|
|
* an error; does anything else depend on this routine treating -1 as
|
|
* meaning "to the end of the buffer"?
|
|
*
|
|
* This function allocates memory from a buffer with packet lifetime.
|
|
* You do not have to free this buffer, it will be automatically freed
|
|
* when wireshark starts decoding the next packet.
|
|
* Do not use this function if you want the allocated memory to be persistent
|
|
* after the current packet has been dissected.
|
|
*/
|
|
void *
|
|
ep_tvb_memdup(tvbuff_t *tvb, const gint offset, size_t length)
|
|
{
|
|
guint abs_offset, abs_length;
|
|
void *duped;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, (gint) length, &abs_offset, &abs_length);
|
|
|
|
duped = ep_alloc(abs_length);
|
|
return tvb_memcpy(tvb, duped, abs_offset, abs_length);
|
|
}
|
|
|
|
|
|
|
|
const guint8*
|
|
tvb_get_ptr(tvbuff_t *tvb, const gint offset, const gint length)
|
|
{
|
|
return ensure_contiguous(tvb, offset, length);
|
|
}
|
|
|
|
/* ---------------- */
|
|
guint8
|
|
tvb_get_guint8(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint8));
|
|
return *ptr;
|
|
}
|
|
|
|
guint16
|
|
tvb_get_ntohs(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint16));
|
|
return pntohs(ptr);
|
|
}
|
|
|
|
guint32
|
|
tvb_get_ntoh24(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 3);
|
|
return pntoh24(ptr);
|
|
}
|
|
|
|
guint32
|
|
tvb_get_ntohl(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint32));
|
|
return pntohl(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_ntoh40(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 5);
|
|
return pntoh40(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_ntoh48(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 6);
|
|
return pntoh48(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_ntoh56(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 7);
|
|
return pntoh56(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_ntoh64(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint64));
|
|
return pntoh64(ptr);
|
|
}
|
|
|
|
/*
|
|
* Stuff for IEEE float handling on platforms that don't have IEEE
|
|
* format as the native floating-point format.
|
|
*
|
|
* For now, we treat only the VAX as such a platform.
|
|
*
|
|
* XXX - other non-IEEE boxes that can run UNIX include some Crays,
|
|
* and possibly other machines.
|
|
*
|
|
* It appears that the official Linux port to System/390 and
|
|
* zArchitecture uses IEEE format floating point (not a
|
|
* huge surprise).
|
|
*
|
|
* I don't know whether there are any other machines that
|
|
* could run Wireshark and that don't use IEEE format.
|
|
* As far as I know, all of the main commercial microprocessor
|
|
* families on which OSes that support Wireshark can run
|
|
* use IEEE format (x86, 68k, SPARC, MIPS, PA-RISC, Alpha,
|
|
* IA-64, and so on).
|
|
*/
|
|
|
|
#if defined(vax)
|
|
|
|
#include <math.h>
|
|
|
|
/*
|
|
* Single-precision.
|
|
*/
|
|
#define IEEE_SP_NUMBER_WIDTH 32 /* bits in number */
|
|
#define IEEE_SP_EXP_WIDTH 8 /* bits in exponent */
|
|
#define IEEE_SP_MANTISSA_WIDTH 23 /* IEEE_SP_NUMBER_WIDTH - 1 - IEEE_SP_EXP_WIDTH */
|
|
|
|
#define IEEE_SP_SIGN_MASK 0x80000000
|
|
#define IEEE_SP_EXPONENT_MASK 0x7F800000
|
|
#define IEEE_SP_MANTISSA_MASK 0x007FFFFF
|
|
#define IEEE_SP_INFINITY IEEE_SP_EXPONENT_MASK
|
|
|
|
#define IEEE_SP_IMPLIED_BIT (1 << IEEE_SP_MANTISSA_WIDTH)
|
|
#define IEEE_SP_INFINITE ((1 << IEEE_SP_EXP_WIDTH) - 1)
|
|
#define IEEE_SP_BIAS ((1 << (IEEE_SP_EXP_WIDTH - 1)) - 1)
|
|
|
|
static int
|
|
ieee_float_is_zero(const guint32 w)
|
|
{
|
|
return ((w & ~IEEE_SP_SIGN_MASK) == 0);
|
|
}
|
|
|
|
static gfloat
|
|
get_ieee_float(const guint32 w)
|
|
{
|
|
long sign;
|
|
long exponent;
|
|
long mantissa;
|
|
|
|
sign = w & IEEE_SP_SIGN_MASK;
|
|
exponent = w & IEEE_SP_EXPONENT_MASK;
|
|
mantissa = w & IEEE_SP_MANTISSA_MASK;
|
|
|
|
if (ieee_float_is_zero(w)) {
|
|
/* number is zero, unnormalized, or not-a-number */
|
|
return 0.0;
|
|
}
|
|
#if 0
|
|
/*
|
|
* XXX - how to handle this?
|
|
*/
|
|
if (IEEE_SP_INFINITY == exponent) {
|
|
/*
|
|
* number is positive or negative infinity, or a special value
|
|
*/
|
|
return (sign? MINUS_INFINITY: PLUS_INFINITY);
|
|
}
|
|
#endif
|
|
|
|
exponent = ((exponent >> IEEE_SP_MANTISSA_WIDTH) - IEEE_SP_BIAS) -
|
|
IEEE_SP_MANTISSA_WIDTH;
|
|
mantissa |= IEEE_SP_IMPLIED_BIT;
|
|
|
|
if (sign)
|
|
return -mantissa * pow(2, exponent);
|
|
else
|
|
return mantissa * pow(2, exponent);
|
|
}
|
|
|
|
/*
|
|
* Double-precision.
|
|
* We assume that if you don't have IEEE floating-point, you have a
|
|
* compiler that understands 64-bit integral quantities.
|
|
*/
|
|
#define IEEE_DP_NUMBER_WIDTH 64 /* bits in number */
|
|
#define IEEE_DP_EXP_WIDTH 11 /* bits in exponent */
|
|
#define IEEE_DP_MANTISSA_WIDTH 52 /* IEEE_DP_NUMBER_WIDTH - 1 - IEEE_DP_EXP_WIDTH */
|
|
|
|
#define IEEE_DP_SIGN_MASK 0x8000000000000000LL
|
|
#define IEEE_DP_EXPONENT_MASK 0x7FF0000000000000LL
|
|
#define IEEE_DP_MANTISSA_MASK 0x000FFFFFFFFFFFFFLL
|
|
#define IEEE_DP_INFINITY IEEE_DP_EXPONENT_MASK
|
|
|
|
#define IEEE_DP_IMPLIED_BIT (1LL << IEEE_DP_MANTISSA_WIDTH)
|
|
#define IEEE_DP_INFINITE ((1 << IEEE_DP_EXP_WIDTH) - 1)
|
|
#define IEEE_DP_BIAS ((1 << (IEEE_DP_EXP_WIDTH - 1)) - 1)
|
|
|
|
static int
|
|
ieee_double_is_zero(const guint64 w)
|
|
{
|
|
return ((w & ~IEEE_SP_SIGN_MASK) == 0);
|
|
}
|
|
|
|
static gdouble
|
|
get_ieee_double(const guint64 w)
|
|
{
|
|
gint64 sign;
|
|
gint64 exponent;
|
|
gint64 mantissa;
|
|
|
|
sign = w & IEEE_DP_SIGN_MASK;
|
|
exponent = w & IEEE_DP_EXPONENT_MASK;
|
|
mantissa = w & IEEE_DP_MANTISSA_MASK;
|
|
|
|
if (ieee_double_is_zero(w)) {
|
|
/* number is zero, unnormalized, or not-a-number */
|
|
return 0.0;
|
|
}
|
|
#if 0
|
|
/*
|
|
* XXX - how to handle this?
|
|
*/
|
|
if (IEEE_DP_INFINITY == exponent) {
|
|
/*
|
|
* number is positive or negative infinity, or a special value
|
|
*/
|
|
return (sign? MINUS_INFINITY: PLUS_INFINITY);
|
|
}
|
|
#endif
|
|
|
|
exponent = ((exponent >> IEEE_DP_MANTISSA_WIDTH) - IEEE_DP_BIAS) -
|
|
IEEE_DP_MANTISSA_WIDTH;
|
|
mantissa |= IEEE_DP_IMPLIED_BIT;
|
|
|
|
if (sign)
|
|
return -mantissa * pow(2, exponent);
|
|
else
|
|
return mantissa * pow(2, exponent);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Fetches an IEEE single-precision floating-point number, in
|
|
* big-endian form, and returns a "float".
|
|
*
|
|
* XXX - should this be "double", in case there are IEEE single-
|
|
* precision numbers that won't fit in some platform's native
|
|
* "float" format?
|
|
*/
|
|
gfloat
|
|
tvb_get_ntohieee_float(tvbuff_t *tvb, const int offset)
|
|
{
|
|
#if defined(vax)
|
|
return get_ieee_float(tvb_get_ntohl(tvb, offset));
|
|
#else
|
|
union {
|
|
gfloat f;
|
|
guint32 w;
|
|
} ieee_fp_union;
|
|
|
|
ieee_fp_union.w = tvb_get_ntohl(tvb, offset);
|
|
return ieee_fp_union.f;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Fetches an IEEE double-precision floating-point number, in
|
|
* big-endian form, and returns a "double".
|
|
*/
|
|
gdouble
|
|
tvb_get_ntohieee_double(tvbuff_t *tvb, const int offset)
|
|
{
|
|
#if defined(vax)
|
|
union {
|
|
guint32 w[2];
|
|
guint64 dw;
|
|
} ieee_fp_union;
|
|
#else
|
|
union {
|
|
gdouble d;
|
|
guint32 w[2];
|
|
} ieee_fp_union;
|
|
#endif
|
|
|
|
#ifdef WORDS_BIGENDIAN
|
|
ieee_fp_union.w[0] = tvb_get_ntohl(tvb, offset);
|
|
ieee_fp_union.w[1] = tvb_get_ntohl(tvb, offset+4);
|
|
#else
|
|
ieee_fp_union.w[0] = tvb_get_ntohl(tvb, offset+4);
|
|
ieee_fp_union.w[1] = tvb_get_ntohl(tvb, offset);
|
|
#endif
|
|
#if defined(vax)
|
|
return get_ieee_double(ieee_fp_union.dw);
|
|
#else
|
|
return ieee_fp_union.d;
|
|
#endif
|
|
}
|
|
|
|
guint16
|
|
tvb_get_letohs(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint16));
|
|
return pletohs(ptr);
|
|
}
|
|
|
|
guint32
|
|
tvb_get_letoh24(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 3);
|
|
return pletoh24(ptr);
|
|
}
|
|
|
|
guint32
|
|
tvb_get_letohl(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint32));
|
|
return pletohl(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_letoh40(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 5);
|
|
return pletoh40(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_letoh48(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 6);
|
|
return pletoh48(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_letoh56(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, 7);
|
|
return pletoh56(ptr);
|
|
}
|
|
|
|
guint64
|
|
tvb_get_letoh64(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint64));
|
|
return pletoh64(ptr);
|
|
}
|
|
|
|
/*
|
|
* Fetches an IEEE single-precision floating-point number, in
|
|
* little-endian form, and returns a "float".
|
|
*
|
|
* XXX - should this be "double", in case there are IEEE single-
|
|
* precision numbers that won't fit in some platform's native
|
|
* "float" format?
|
|
*/
|
|
gfloat
|
|
tvb_get_letohieee_float(tvbuff_t *tvb, const int offset)
|
|
{
|
|
#if defined(vax)
|
|
return get_ieee_float(tvb_get_letohl(tvb, offset));
|
|
#else
|
|
union {
|
|
gfloat f;
|
|
guint32 w;
|
|
} ieee_fp_union;
|
|
|
|
ieee_fp_union.w = tvb_get_letohl(tvb, offset);
|
|
return ieee_fp_union.f;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Fetches an IEEE double-precision floating-point number, in
|
|
* little-endian form, and returns a "double".
|
|
*/
|
|
gdouble
|
|
tvb_get_letohieee_double(tvbuff_t *tvb, const int offset)
|
|
{
|
|
#if defined(vax)
|
|
union {
|
|
guint32 w[2];
|
|
guint64 dw;
|
|
} ieee_fp_union;
|
|
#else
|
|
union {
|
|
gdouble d;
|
|
guint32 w[2];
|
|
} ieee_fp_union;
|
|
#endif
|
|
|
|
#ifdef WORDS_BIGENDIAN
|
|
ieee_fp_union.w[0] = tvb_get_letohl(tvb, offset+4);
|
|
ieee_fp_union.w[1] = tvb_get_letohl(tvb, offset);
|
|
#else
|
|
ieee_fp_union.w[0] = tvb_get_letohl(tvb, offset);
|
|
ieee_fp_union.w[1] = tvb_get_letohl(tvb, offset+4);
|
|
#endif
|
|
#if defined(vax)
|
|
return get_ieee_double(ieee_fp_union.dw);
|
|
#else
|
|
return ieee_fp_union.d;
|
|
#endif
|
|
}
|
|
|
|
/* Fetch an IPv4 address, in network byte order.
|
|
* We do *not* convert them to host byte order; we leave them in
|
|
* network byte order. */
|
|
guint32
|
|
tvb_get_ipv4(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
const guint8 *ptr;
|
|
guint32 addr;
|
|
|
|
ptr = fast_ensure_contiguous(tvb, offset, sizeof(guint32));
|
|
memcpy(&addr, ptr, sizeof addr);
|
|
return addr;
|
|
}
|
|
|
|
/* Fetch an IPv6 address. */
|
|
void
|
|
tvb_get_ipv6(tvbuff_t *tvb, const gint offset, struct e_in6_addr *addr)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = ensure_contiguous(tvb, offset, sizeof(*addr));
|
|
memcpy(addr, ptr, sizeof *addr);
|
|
}
|
|
|
|
/* Fetch a GUID. */
|
|
void
|
|
tvb_get_ntohguid(tvbuff_t *tvb, const gint offset, e_guid_t *guid)
|
|
{
|
|
ensure_contiguous(tvb, offset, sizeof(*guid));
|
|
guid->data1 = tvb_get_ntohl(tvb, offset);
|
|
guid->data2 = tvb_get_ntohs(tvb, offset + 4);
|
|
guid->data3 = tvb_get_ntohs(tvb, offset + 6);
|
|
tvb_memcpy(tvb, guid->data4, offset + 8, sizeof guid->data4);
|
|
}
|
|
|
|
void
|
|
tvb_get_letohguid(tvbuff_t *tvb, const gint offset, e_guid_t *guid)
|
|
{
|
|
ensure_contiguous(tvb, offset, sizeof(*guid));
|
|
guid->data1 = tvb_get_letohl(tvb, offset);
|
|
guid->data2 = tvb_get_letohs(tvb, offset + 4);
|
|
guid->data3 = tvb_get_letohs(tvb, offset + 6);
|
|
tvb_memcpy(tvb, guid->data4, offset + 8, sizeof guid->data4);
|
|
}
|
|
|
|
/*
|
|
* NOTE: to support code written when proto_tree_add_item() took a
|
|
* gboolean as its last argument, with FALSE meaning "big-endian"
|
|
* and TRUE meaning "little-endian", we treat any non-zero value of
|
|
* "representation" as meaning "little-endian".
|
|
*/
|
|
void
|
|
tvb_get_guid(tvbuff_t *tvb, const gint offset, e_guid_t *guid, const guint representation)
|
|
{
|
|
if (representation) {
|
|
tvb_get_letohguid(tvb, offset, guid);
|
|
} else {
|
|
tvb_get_ntohguid(tvb, offset, guid);
|
|
}
|
|
}
|
|
|
|
static const guint8 inverse_bit_mask8[] = {
|
|
0xff,
|
|
0x7f,
|
|
0x3f,
|
|
0x1f,
|
|
0x0f,
|
|
0x07,
|
|
0x03,
|
|
0x01
|
|
};
|
|
|
|
static const guint8 bit_mask8[] = {
|
|
0x00,
|
|
0x01,
|
|
0x03,
|
|
0x07,
|
|
0x0f,
|
|
0x1f,
|
|
0x3f,
|
|
0x7f,
|
|
0xff
|
|
};
|
|
|
|
/* Get 1 - 8 bits */
|
|
guint8
|
|
tvb_get_bits8(tvbuff_t *tvb, guint bit_offset, const gint no_of_bits)
|
|
{
|
|
return (guint8)_tvb_get_bits64(tvb, bit_offset, no_of_bits);
|
|
}
|
|
|
|
/* Get 1 - 16 bits */
|
|
void
|
|
tvb_get_bits_buf(tvbuff_t *tvb, guint bit_offset, gint no_of_bits, guint8 *buf, gboolean lsb0)
|
|
{
|
|
guint8 bit_mask, bit_shift;
|
|
/* Byte align offset */
|
|
gint offset = bit_offset >> 3;
|
|
|
|
bit_offset = bit_offset & 0x7;
|
|
|
|
bit_mask = (lsb0) ? 0xff : inverse_bit_mask8[bit_offset];
|
|
bit_shift = (lsb0) ? bit_offset : (8 - bit_offset);
|
|
|
|
if (G_LIKELY(bit_offset != 0)) {
|
|
guint16 value = (guint16) tvb_get_guint8(tvb, offset);
|
|
|
|
while (no_of_bits >= 8) {
|
|
offset++;
|
|
value = ((value & bit_mask) << 8) | tvb_get_guint8(tvb, offset);
|
|
|
|
if (lsb0)
|
|
*buf++ = (guint8) (GUINT16_SWAP_LE_BE(value) >> bit_shift);
|
|
else
|
|
*buf++ = (guint8) (value >> bit_shift);
|
|
no_of_bits -= 8;
|
|
}
|
|
|
|
/* something left? */
|
|
if (no_of_bits > 0) {
|
|
guint8 tot_no_bits = bit_offset+no_of_bits;
|
|
|
|
/* Overlaps with next byte? Get next byte */
|
|
if (tot_no_bits > 8) {
|
|
offset++;
|
|
value = ((value & bit_mask) << 8) | tvb_get_guint8(tvb, offset);
|
|
}
|
|
|
|
if (lsb0) {
|
|
if (tot_no_bits > 8)
|
|
value = (GUINT16_SWAP_LE_BE(value) >> bit_offset) & (bit_mask8[no_of_bits]);
|
|
else
|
|
value = (value >> bit_offset) & (bit_mask8[no_of_bits]);
|
|
|
|
/* value = (value & ((1 << tot_no_bits)-1)) >> bit_offset; */
|
|
|
|
} else {
|
|
if (tot_no_bits > 8)
|
|
value = value >> (16 - tot_no_bits);
|
|
else
|
|
value = (value & bit_mask) >> (8-tot_no_bits);
|
|
}
|
|
*buf = (guint8) value;
|
|
}
|
|
|
|
} else {
|
|
/* fast code path for bit_offset == 0 */
|
|
while (no_of_bits >= 8) {
|
|
*buf++ = tvb_get_guint8(tvb, offset);
|
|
offset++;
|
|
no_of_bits -= 8;
|
|
}
|
|
|
|
/* something left? */
|
|
if (no_of_bits > 0) {
|
|
if (lsb0)
|
|
*buf = tvb_get_guint8(tvb, offset) & bit_mask8[no_of_bits]; /* read: ((1 << no_of_bits)-1) */
|
|
else
|
|
*buf = tvb_get_guint8(tvb, offset) >> (8-no_of_bits);
|
|
}
|
|
}
|
|
}
|
|
|
|
guint8 *
|
|
ep_tvb_get_bits(tvbuff_t *tvb, guint bit_offset, gint no_of_bits, gboolean lsb0)
|
|
{
|
|
gint no_of_bytes;
|
|
guint8 *buf;
|
|
|
|
/* XXX, no_of_bits == -1 -> to end of tvb? */
|
|
|
|
if (no_of_bits < 0) {
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
}
|
|
|
|
no_of_bytes = (no_of_bits >> 3) + ((no_of_bits & 0x7) != 0); /* ceil(no_of_bits / 8.0) */
|
|
buf = ep_alloc(no_of_bytes);
|
|
tvb_get_bits_buf(tvb, bit_offset, no_of_bits, buf, lsb0);
|
|
return buf;
|
|
}
|
|
|
|
/* Get 9 - 16 bits */
|
|
guint16
|
|
tvb_get_bits16(tvbuff_t *tvb, guint bit_offset, const gint no_of_bits,const guint encoding _U_)
|
|
{
|
|
/* note that encoding has no meaning here, as the tvb is considered to contain an octet array */
|
|
return (guint16)_tvb_get_bits64(tvb, bit_offset, no_of_bits);
|
|
}
|
|
|
|
/* Get 1 - 32 bits */
|
|
guint32
|
|
tvb_get_bits32(tvbuff_t *tvb, guint bit_offset, const gint no_of_bits, const guint encoding _U_)
|
|
{
|
|
/* note that encoding has no meaning here, as the tvb is considered to contain an octet array */
|
|
return (guint32)_tvb_get_bits64(tvb, bit_offset, no_of_bits);
|
|
}
|
|
|
|
/* Get 1 - 64 bits */
|
|
guint64
|
|
tvb_get_bits64(tvbuff_t *tvb, guint bit_offset, const gint no_of_bits, const guint encoding _U_)
|
|
{
|
|
/* note that encoding has no meaning here, as the tvb is considered to contain an octet array */
|
|
return _tvb_get_bits64(tvb, bit_offset, no_of_bits);
|
|
}
|
|
/*
|
|
* This function will dissect a sequence of bits that does not need to be byte aligned; the bits
|
|
* set will be shown in the tree as ..10 10.. and the integer value returned if return_value is set.
|
|
* Offset should be given in bits from the start of the tvb.
|
|
* The function tolerates requests for more than 64 bits, but will only return the least significant 64 bits.
|
|
*/
|
|
static guint64
|
|
_tvb_get_bits64(tvbuff_t *tvb, guint bit_offset, const gint total_no_of_bits)
|
|
{
|
|
guint64 value;
|
|
guint octet_offset = bit_offset >> 3;
|
|
guint8 required_bits_in_first_octet = 8 - (bit_offset % 8);
|
|
|
|
if(required_bits_in_first_octet > total_no_of_bits)
|
|
{
|
|
/* the required bits don't extend to the end of the first octet */
|
|
guint8 right_shift = required_bits_in_first_octet - total_no_of_bits;
|
|
value = (tvb_get_guint8(tvb, octet_offset) >> right_shift) & bit_mask8[total_no_of_bits % 8];
|
|
}
|
|
else
|
|
{
|
|
guint8 remaining_bit_length = total_no_of_bits;
|
|
|
|
/* get the bits up to the first octet boundary */
|
|
value = 0;
|
|
required_bits_in_first_octet %= 8;
|
|
if(required_bits_in_first_octet != 0)
|
|
{
|
|
value = tvb_get_guint8(tvb, octet_offset) & bit_mask8[required_bits_in_first_octet];
|
|
remaining_bit_length -= required_bits_in_first_octet;
|
|
octet_offset ++;
|
|
}
|
|
/* take the biggest words, shorts or octets that we can */
|
|
while (remaining_bit_length > 7)
|
|
{
|
|
switch (remaining_bit_length >> 4)
|
|
{
|
|
case 0:
|
|
/* 8 - 15 bits. (note that 0 - 7 would have dropped out of the while() loop) */
|
|
value <<= 8;
|
|
value += tvb_get_guint8(tvb, octet_offset);
|
|
remaining_bit_length -= 8;
|
|
octet_offset ++;
|
|
break;
|
|
|
|
case 1:
|
|
/* 16 - 31 bits */
|
|
value <<= 16;
|
|
value += tvb_get_ntohs(tvb, octet_offset);
|
|
remaining_bit_length -= 16;
|
|
octet_offset += 2;
|
|
break;
|
|
|
|
case 2:
|
|
case 3:
|
|
/* 32 - 63 bits */
|
|
value <<= 32;
|
|
value += tvb_get_ntohl(tvb, octet_offset);
|
|
remaining_bit_length -= 32;
|
|
octet_offset += 4;
|
|
break;
|
|
|
|
default:
|
|
/* 64 bits (or more???) */
|
|
value = tvb_get_ntoh64(tvb, octet_offset);
|
|
remaining_bit_length -= 64;
|
|
octet_offset += 8;
|
|
break;
|
|
}
|
|
}
|
|
/* get bits from any partial octet at the tail */
|
|
if(remaining_bit_length)
|
|
{
|
|
value <<= remaining_bit_length;
|
|
value += (tvb_get_guint8(tvb, octet_offset) >> (8 - remaining_bit_length));
|
|
}
|
|
}
|
|
return value;
|
|
}
|
|
/* Get 1 - 32 bits (should be deprecated as same as tvb_get_bits32??) */
|
|
guint32
|
|
tvb_get_bits(tvbuff_t *tvb, const guint bit_offset, const gint no_of_bits, const guint encoding _U_)
|
|
{
|
|
/* note that encoding has no meaning here, as the tvb is considered to contain an octet array */
|
|
return (guint32)_tvb_get_bits64(tvb, bit_offset, no_of_bits);
|
|
}
|
|
|
|
/* Find first occurence of needle in tvbuff, starting at offset. Searches
|
|
* at most maxlength number of bytes; if maxlength is -1, searches to
|
|
* end of tvbuff.
|
|
* Returns the offset of the found needle, or -1 if not found.
|
|
* Will not throw an exception, even if maxlength exceeds boundary of tvbuff;
|
|
* in that case, -1 will be returned if the boundary is reached before
|
|
* finding needle. */
|
|
gint
|
|
tvb_find_guint8(tvbuff_t *tvb, const gint offset, const gint maxlength, const guint8 needle)
|
|
{
|
|
const guint8 *result;
|
|
guint abs_offset, junk_length;
|
|
guint tvbufflen;
|
|
guint limit;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, 0, &abs_offset, &junk_length);
|
|
|
|
/* Only search to end of tvbuff, w/o throwing exception. */
|
|
tvbufflen = tvb_length_remaining(tvb, abs_offset);
|
|
if (maxlength == -1) {
|
|
/* No maximum length specified; search to end of tvbuff. */
|
|
limit = tvbufflen;
|
|
}
|
|
else if (tvbufflen < (guint) maxlength) {
|
|
/* Maximum length goes past end of tvbuff; search to end
|
|
of tvbuff. */
|
|
limit = tvbufflen;
|
|
}
|
|
else {
|
|
/* Maximum length doesn't go past end of tvbuff; search
|
|
to that value. */
|
|
limit = maxlength;
|
|
}
|
|
|
|
/* If we have real data, perform our search now. */
|
|
if (tvb->real_data) {
|
|
result = memchr(tvb->real_data + abs_offset, needle, limit);
|
|
if (result == NULL) {
|
|
return -1;
|
|
}
|
|
else {
|
|
return (gint) (result - tvb->real_data);
|
|
}
|
|
}
|
|
|
|
switch(tvb->type) {
|
|
case TVBUFF_REAL_DATA:
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
|
|
case TVBUFF_SUBSET:
|
|
return tvb_find_guint8(tvb->tvbuffs.subset.tvb,
|
|
abs_offset - tvb->tvbuffs.subset.offset,
|
|
limit, needle);
|
|
|
|
case TVBUFF_COMPOSITE:
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
/* XXX - return composite_find_guint8(tvb, offset, limit, needle); */
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
return -1;
|
|
}
|
|
|
|
/* Find first occurence of any of the needles in tvbuff, starting at offset.
|
|
* Searches at most maxlength number of bytes; if maxlength is -1, searches
|
|
* to end of tvbuff.
|
|
* Returns the offset of the found needle, or -1 if not found.
|
|
* Will not throw an exception, even if maxlength exceeds boundary of tvbuff;
|
|
* in that case, -1 will be returned if the boundary is reached before
|
|
* finding needle. */
|
|
gint
|
|
tvb_pbrk_guint8(tvbuff_t *tvb, const gint offset, const gint maxlength, const guint8 *needles, guchar *found_needle)
|
|
{
|
|
const guint8 *result;
|
|
guint abs_offset, junk_length;
|
|
guint tvbufflen;
|
|
guint limit;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, 0, &abs_offset, &junk_length);
|
|
|
|
/* Only search to end of tvbuff, w/o throwing exception. */
|
|
tvbufflen = tvb_length_remaining(tvb, abs_offset);
|
|
if (maxlength == -1) {
|
|
/* No maximum length specified; search to end of tvbuff. */
|
|
limit = tvbufflen;
|
|
}
|
|
else if (tvbufflen < (guint) maxlength) {
|
|
/* Maximum length goes past end of tvbuff; search to end
|
|
of tvbuff. */
|
|
limit = tvbufflen;
|
|
}
|
|
else {
|
|
/* Maximum length doesn't go past end of tvbuff; search
|
|
to that value. */
|
|
limit = maxlength;
|
|
}
|
|
|
|
/* If we have real data, perform our search now. */
|
|
if (tvb->real_data) {
|
|
result = guint8_pbrk(tvb->real_data + abs_offset, limit, needles, found_needle);
|
|
if (result == NULL) {
|
|
return -1;
|
|
}
|
|
else {
|
|
return (gint) (result - tvb->real_data);
|
|
}
|
|
}
|
|
|
|
switch(tvb->type) {
|
|
case TVBUFF_REAL_DATA:
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
|
|
case TVBUFF_SUBSET:
|
|
return tvb_pbrk_guint8(tvb->tvbuffs.subset.tvb,
|
|
abs_offset - tvb->tvbuffs.subset.offset,
|
|
limit, needles, found_needle);
|
|
|
|
case TVBUFF_COMPOSITE:
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
/* XXX - return composite_pbrk_guint8(tvb, offset, limit, needle); */
|
|
}
|
|
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
return -1;
|
|
}
|
|
|
|
/* Find size of stringz (NUL-terminated string) by looking for terminating
|
|
* NUL. The size of the string includes the terminating NUL.
|
|
*
|
|
* If the NUL isn't found, it throws the appropriate exception.
|
|
*/
|
|
guint
|
|
tvb_strsize(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
guint abs_offset, junk_length;
|
|
gint nul_offset;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, 0, &abs_offset, &junk_length);
|
|
nul_offset = tvb_find_guint8(tvb, abs_offset, -1, 0);
|
|
if (nul_offset == -1) {
|
|
/*
|
|
* OK, we hit the end of the tvbuff, so we should throw
|
|
* an exception.
|
|
*
|
|
* Did we hit the end of the captured data, or the end
|
|
* of the actual data? If there's less captured data
|
|
* than actual data, we presumably hit the end of the
|
|
* captured data, otherwise we hit the end of the actual
|
|
* data.
|
|
*/
|
|
if (tvb_length(tvb) < tvb_reported_length(tvb)) {
|
|
THROW(BoundsError);
|
|
} else {
|
|
THROW(ReportedBoundsError);
|
|
}
|
|
}
|
|
return (nul_offset - abs_offset) + 1;
|
|
}
|
|
|
|
/* UTF-16/UCS-2 version of tvb_strsize */
|
|
/* Returns number of bytes including the (two-bytes) null terminator */
|
|
guint
|
|
tvb_unicode_strsize(tvbuff_t *tvb, const gint offset)
|
|
{
|
|
guint i = 0;
|
|
gunichar2 uchar;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
do {
|
|
/* Endianness doesn't matter when looking for null */
|
|
uchar = tvb_get_ntohs(tvb, offset + i);
|
|
i += 2;
|
|
} while(uchar != 0);
|
|
|
|
return i;
|
|
}
|
|
|
|
/* Find length of string by looking for end of string ('\0'), up to
|
|
* 'maxlength' characters'; if 'maxlength' is -1, searches to end
|
|
* of tvbuff.
|
|
* Returns -1 if 'maxlength' reached before finding EOS. */
|
|
gint
|
|
tvb_strnlen(tvbuff_t *tvb, const gint offset, const guint maxlength)
|
|
{
|
|
gint result_offset;
|
|
guint abs_offset, junk_length;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, 0, &abs_offset, &junk_length);
|
|
|
|
result_offset = tvb_find_guint8(tvb, abs_offset, maxlength, 0);
|
|
|
|
if (result_offset == -1) {
|
|
return -1;
|
|
}
|
|
else {
|
|
return result_offset - abs_offset;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Implement strneql etc
|
|
*/
|
|
|
|
/*
|
|
* Call strncmp after checking if enough chars left, returning 0 if
|
|
* it returns 0 (meaning "equal") and -1 otherwise, otherwise return -1.
|
|
*/
|
|
gint
|
|
tvb_strneql(tvbuff_t *tvb, const gint offset, const gchar *str, const size_t size)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = ensure_contiguous_no_exception(tvb, offset, (gint)size, NULL);
|
|
|
|
if (ptr) {
|
|
int cmp = strncmp((const char *)ptr, str, size);
|
|
|
|
/*
|
|
* Return 0 if equal, -1 otherwise.
|
|
*/
|
|
return (cmp == 0 ? 0 : -1);
|
|
} else {
|
|
/*
|
|
* Not enough characters in the tvbuff to match the
|
|
* string.
|
|
*/
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Call g_ascii_strncasecmp after checking if enough chars left, returning
|
|
* 0 if it returns 0 (meaning "equal") and -1 otherwise, otherwise return -1.
|
|
*/
|
|
gint
|
|
tvb_strncaseeql(tvbuff_t *tvb, const gint offset, const gchar *str, const size_t size)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = ensure_contiguous_no_exception(tvb, offset, (gint)size, NULL);
|
|
|
|
if (ptr) {
|
|
int cmp = g_ascii_strncasecmp((const char *)ptr, str, size);
|
|
|
|
/*
|
|
* Return 0 if equal, -1 otherwise.
|
|
*/
|
|
return (cmp == 0 ? 0 : -1);
|
|
} else {
|
|
/*
|
|
* Not enough characters in the tvbuff to match the
|
|
* string.
|
|
*/
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Call memcmp after checking if enough chars left, returning 0 if
|
|
* it returns 0 (meaning "equal") and -1 otherwise, otherwise return -1.
|
|
*/
|
|
gint
|
|
tvb_memeql(tvbuff_t *tvb, const gint offset, const guint8 *str, size_t size)
|
|
{
|
|
const guint8 *ptr;
|
|
|
|
ptr = ensure_contiguous_no_exception(tvb, offset, (gint) size, NULL);
|
|
|
|
if (ptr) {
|
|
int cmp = memcmp(ptr, str, size);
|
|
|
|
/*
|
|
* Return 0 if equal, -1 otherwise.
|
|
*/
|
|
return (cmp == 0 ? 0 : -1);
|
|
} else {
|
|
/*
|
|
* Not enough characters in the tvbuff to match the
|
|
* string.
|
|
*/
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* Convert a string from Unicode to ASCII. At the moment we fake it by
|
|
* replacing all non-ASCII characters with a '.' )-: The caller must
|
|
* free the result returned. The len parameter is the number of guint16's
|
|
* to convert from Unicode. */
|
|
/* XXX - this function has been superceded by tvb_get_unicode_string() */
|
|
char *
|
|
tvb_fake_unicode(tvbuff_t *tvb, int offset, const int len, const gboolean little_endian)
|
|
{
|
|
char *buffer;
|
|
int i;
|
|
guint16 character;
|
|
|
|
/* Make sure we have enough data before allocating the buffer,
|
|
so we don't blow up if the length is huge. */
|
|
tvb_ensure_bytes_exist(tvb, offset, 2*len);
|
|
|
|
/* We know we won't throw an exception, so we don't have to worry
|
|
about leaking this buffer. */
|
|
buffer = g_malloc(len + 1);
|
|
|
|
for (i = 0; i < len; i++) {
|
|
character = little_endian ? tvb_get_letohs(tvb, offset)
|
|
: tvb_get_ntohs(tvb, offset);
|
|
buffer[i] = character < 256 ? character : '.';
|
|
offset += 2;
|
|
}
|
|
|
|
buffer[len] = 0;
|
|
|
|
return buffer;
|
|
}
|
|
|
|
/* Convert a string from Unicode to ASCII. At the moment we fake it by
|
|
* replacing all non-ASCII characters with a '.' )-: The len parameter is
|
|
* the number of guint16's to convert from Unicode.
|
|
*
|
|
* This function allocates memory from a buffer with packet lifetime.
|
|
* You do not have to free this buffer, it will be automatically freed
|
|
* when wireshark starts decoding the next packet.
|
|
*/
|
|
/* XXX: This has been replaced by tvb_get_ephemeral_unicode_string() */
|
|
char *
|
|
tvb_get_ephemeral_faked_unicode(tvbuff_t *tvb, int offset, const int len, const gboolean little_endian)
|
|
{
|
|
char *buffer;
|
|
int i;
|
|
guint16 character;
|
|
|
|
/* Make sure we have enough data before allocating the buffer,
|
|
so we don't blow up if the length is huge. */
|
|
tvb_ensure_bytes_exist(tvb, offset, 2*len);
|
|
|
|
/* We know we won't throw an exception, so we don't have to worry
|
|
about leaking this buffer. */
|
|
buffer = ep_alloc(len + 1);
|
|
|
|
for (i = 0; i < len; i++) {
|
|
character = little_endian ? tvb_get_letohs(tvb, offset)
|
|
: tvb_get_ntohs(tvb, offset);
|
|
buffer[i] = character < 256 ? character : '.';
|
|
offset += 2;
|
|
}
|
|
|
|
buffer[len] = 0;
|
|
|
|
return buffer;
|
|
}
|
|
|
|
/*
|
|
* Format the data in the tvb from offset for length ...
|
|
*/
|
|
|
|
gchar *
|
|
tvb_format_text(tvbuff_t *tvb, const gint offset, const gint size)
|
|
{
|
|
const guint8 *ptr;
|
|
gint len = size;
|
|
|
|
if ((ptr = ensure_contiguous(tvb, offset, size)) == NULL) {
|
|
len = tvb_length_remaining(tvb, offset);
|
|
ptr = ensure_contiguous(tvb, offset, len);
|
|
}
|
|
|
|
return format_text(ptr, len);
|
|
}
|
|
|
|
/*
|
|
* Format the data in the tvb from offset for length ...
|
|
*/
|
|
|
|
gchar *
|
|
tvb_format_text_wsp(tvbuff_t *tvb, const gint offset, const gint size)
|
|
{
|
|
const guint8 *ptr;
|
|
gint len = size;
|
|
|
|
if ((ptr = ensure_contiguous(tvb, offset, size)) == NULL) {
|
|
|
|
len = tvb_length_remaining(tvb, offset);
|
|
ptr = ensure_contiguous(tvb, offset, len);
|
|
|
|
}
|
|
|
|
return format_text_wsp(ptr, len);
|
|
|
|
}
|
|
|
|
/*
|
|
* Like "tvb_format_text()", but for null-padded strings; don't show
|
|
* the null padding characters as "\000".
|
|
*/
|
|
gchar *
|
|
tvb_format_stringzpad(tvbuff_t *tvb, const gint offset, const gint size)
|
|
{
|
|
const guint8 *ptr, *p;
|
|
gint len = size;
|
|
gint stringlen;
|
|
|
|
if ((ptr = ensure_contiguous(tvb, offset, size)) == NULL) {
|
|
|
|
len = tvb_length_remaining(tvb, offset);
|
|
ptr = ensure_contiguous(tvb, offset, len);
|
|
|
|
}
|
|
|
|
for (p = ptr, stringlen = 0; stringlen < len && *p != '\0'; p++, stringlen++)
|
|
;
|
|
return format_text(ptr, stringlen);
|
|
|
|
}
|
|
|
|
/*
|
|
* Like "tvb_format_text_wsp()", but for null-padded strings; don't show
|
|
* the null padding characters as "\000".
|
|
*/
|
|
gchar *
|
|
tvb_format_stringzpad_wsp(tvbuff_t *tvb, const gint offset, const gint size)
|
|
{
|
|
const guint8 *ptr, *p;
|
|
gint len = size;
|
|
gint stringlen;
|
|
|
|
if ((ptr = ensure_contiguous(tvb, offset, size)) == NULL) {
|
|
|
|
len = tvb_length_remaining(tvb, offset);
|
|
ptr = ensure_contiguous(tvb, offset, len);
|
|
|
|
}
|
|
|
|
for (p = ptr, stringlen = 0; stringlen < len && *p != '\0'; p++, stringlen++)
|
|
;
|
|
return format_text_wsp(ptr, stringlen);
|
|
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff, an offset, and a length, allocate a buffer big enough
|
|
* to hold a non-null-terminated string of that length at that offset,
|
|
* plus a trailing '\0', copy the string into it, and return a pointer
|
|
* to the string.
|
|
*
|
|
* Throws an exception if the tvbuff ends before the string does.
|
|
*/
|
|
guint8 *
|
|
tvb_get_string(tvbuff_t *tvb, const gint offset, const gint length)
|
|
{
|
|
const guint8 *ptr;
|
|
guint8 *strbuf = NULL;
|
|
|
|
tvb_ensure_bytes_exist(tvb, offset, length);
|
|
|
|
ptr = ensure_contiguous(tvb, offset, length);
|
|
strbuf = g_malloc(length + 1);
|
|
if (length != 0) {
|
|
memcpy(strbuf, ptr, length);
|
|
}
|
|
strbuf[length] = '\0';
|
|
return strbuf;
|
|
}
|
|
|
|
/*
|
|
* Unicode (UTF-16) version of tvb_get_string()
|
|
* XXX - this is UCS-2, not UTF-16, as it doesn't handle surrogate pairs
|
|
*
|
|
* Encoding paramter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN
|
|
*
|
|
* Specify length in bytes
|
|
*
|
|
* Returns an UTF-8 string that must be freed by the caller
|
|
*/
|
|
gchar *
|
|
tvb_get_unicode_string(tvbuff_t *tvb, const gint offset, gint length, const guint encoding)
|
|
{
|
|
gunichar2 uchar;
|
|
gint i; /* Byte counter for tvbuff */
|
|
GString *strbuf = NULL;
|
|
|
|
tvb_ensure_bytes_exist(tvb, offset, length);
|
|
|
|
strbuf = g_string_new(NULL);
|
|
|
|
for(i = 0; i < length; i += 2) {
|
|
|
|
if (encoding == ENC_BIG_ENDIAN)
|
|
uchar = tvb_get_ntohs(tvb, offset + i);
|
|
else
|
|
uchar = tvb_get_letohs(tvb, offset + i);
|
|
|
|
g_string_append_unichar(strbuf, uchar);
|
|
}
|
|
|
|
return g_string_free(strbuf, FALSE);
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff, an offset, a length, and an encoding, allocate a
|
|
* buffer big enough to hold a non-null-terminated string of that length
|
|
* at that offset, plus a trailing '\0', copy into the buffer the
|
|
* string as converted from the appropriate encoding to UTF-8, and
|
|
* return a pointer to the string.
|
|
*
|
|
* Throws an exception if the tvbuff ends before the string does.
|
|
*
|
|
* This function allocates memory from a buffer with packet lifetime.
|
|
* You do not have to free this buffer, it will be automatically freed
|
|
* when wireshark starts decoding the next packet.
|
|
* Do not use this function if you want the allocated memory to be persistent
|
|
* after the current packet has been dissected.
|
|
*/
|
|
guint8 *
|
|
tvb_get_ephemeral_string_enc(tvbuff_t *tvb, const gint offset,
|
|
const gint length, const guint encoding)
|
|
{
|
|
const guint8 *ptr;
|
|
guint8 *strbuf;
|
|
|
|
switch (encoding & ENC_CHARENCODING_MASK) {
|
|
|
|
case ENC_ASCII:
|
|
default:
|
|
/*
|
|
* For now, we treat bogus values as meaning
|
|
* "ASCII" rather than reporting an error,
|
|
* for the benefit of old dissectors written
|
|
* when the last argument to proto_tree_add_item()
|
|
* was a gboolean for the byte order, not an
|
|
* encoding value, and passed non-zero values
|
|
* other than TRUE to mean "little-endian".
|
|
*
|
|
* XXX - should map all octets with the 8th bit
|
|
* not set to a "substitute" UTF-8 character.
|
|
*/
|
|
strbuf = tvb_get_ephemeral_string(tvb, offset, length);
|
|
break;
|
|
|
|
case ENC_UTF_8:
|
|
/*
|
|
* XXX - should map all invalid UTF-8 sequences
|
|
* to a "substitute" UTF-8 character.
|
|
*/
|
|
strbuf = tvb_get_ephemeral_string(tvb, offset, length);
|
|
break;
|
|
|
|
case ENC_UTF_16:
|
|
/*
|
|
* XXX - needs to handle surrogate pairs and to map
|
|
* invalid characters and sequences to a "substitute"
|
|
* UTF-8 character.
|
|
*/
|
|
strbuf = tvb_get_ephemeral_unicode_string(tvb, offset, length,
|
|
encoding & ENC_LITTLE_ENDIAN);
|
|
break;
|
|
|
|
case ENC_UCS_2:
|
|
/*
|
|
* XXX - needs to map values that are not valid UCS-2
|
|
* characters (such as, I think, values used as the
|
|
* components of a UTF-16 surrogate pair) to a
|
|
* "substitute" UTF-8 character.
|
|
*/
|
|
strbuf = tvb_get_ephemeral_unicode_string(tvb, offset, length,
|
|
encoding & ENC_LITTLE_ENDIAN);
|
|
break;
|
|
|
|
case ENC_EBCDIC:
|
|
/*
|
|
* XXX - do the copy and conversion in one pass.
|
|
*
|
|
* XXX - multiple "dialects" of EBCDIC?
|
|
*/
|
|
tvb_ensure_bytes_exist(tvb, offset, length); /* make sure length = -1 fails */
|
|
strbuf = ep_alloc(length + 1);
|
|
if (length != 0) {
|
|
ptr = ensure_contiguous(tvb, offset, length);
|
|
memcpy(strbuf, ptr, length);
|
|
EBCDIC_to_ASCII(strbuf, length);
|
|
}
|
|
strbuf[length] = '\0';
|
|
break;
|
|
}
|
|
return strbuf;
|
|
}
|
|
|
|
guint8 *
|
|
tvb_get_ephemeral_string(tvbuff_t *tvb, const gint offset, const gint length)
|
|
{
|
|
guint8 *strbuf;
|
|
|
|
tvb_ensure_bytes_exist(tvb, offset, length); /* make sure length = -1 fails */
|
|
strbuf = ep_alloc(length + 1);
|
|
tvb_memcpy(tvb, strbuf, offset, length);
|
|
strbuf[length] = '\0';
|
|
return strbuf;
|
|
}
|
|
|
|
/*
|
|
* Unicode (UTF-16) version of tvb_get_ephemeral_string()
|
|
* XXX - this is UCS-2, not UTF-16, as it doesn't handle surrogate pairs
|
|
*
|
|
* Encoding parameter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN
|
|
*
|
|
* Specify length in bytes
|
|
*
|
|
* Returns an ep_ allocated UTF-8 string
|
|
*/
|
|
gchar *
|
|
tvb_get_ephemeral_unicode_string(tvbuff_t *tvb, const gint offset, gint length, const guint encoding)
|
|
{
|
|
/* Longest UTF-8 character takes 6 bytes + 1 byte for NUL, round it to 8B */
|
|
gchar tmpbuf[8];
|
|
gunichar2 uchar;
|
|
gint i; /* Byte counter for tvbuff */
|
|
gint tmpbuf_len;
|
|
emem_strbuf_t *strbuf = NULL;
|
|
|
|
tvb_ensure_bytes_exist(tvb, offset, length);
|
|
|
|
strbuf = ep_strbuf_new(NULL);
|
|
|
|
for(i = 0; i < length; i += 2) {
|
|
|
|
if (encoding == ENC_BIG_ENDIAN)
|
|
uchar = tvb_get_ntohs(tvb, offset + i);
|
|
else
|
|
uchar = tvb_get_letohs(tvb, offset + i);
|
|
|
|
tmpbuf_len = g_unichar_to_utf8(uchar, tmpbuf);
|
|
|
|
/* NULL terminate the tmpbuf so ep_strbuf_append knows where
|
|
* to stop */
|
|
tmpbuf[tmpbuf_len] = '\0';
|
|
|
|
ep_strbuf_append(strbuf, tmpbuf);
|
|
}
|
|
|
|
return strbuf->str;
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff, an offset, and a length, allocate a buffer big enough
|
|
* to hold a non-null-terminated string of that length at that offset,
|
|
* plus a trailing '\0', copy the string into it, and return a pointer
|
|
* to the string.
|
|
*
|
|
* Throws an exception if the tvbuff ends before the string does.
|
|
*
|
|
* This function allocates memory from a buffer with capture session lifetime.
|
|
* You do not have to free this buffer, it will be automatically freed
|
|
* when wireshark starts or opens a new capture.
|
|
*/
|
|
guint8 *
|
|
tvb_get_seasonal_string(tvbuff_t *tvb, const gint offset, const gint length)
|
|
{
|
|
const guint8 *ptr;
|
|
guint8 *strbuf = NULL;
|
|
|
|
tvb_ensure_bytes_exist(tvb, offset, length);
|
|
|
|
ptr = ensure_contiguous(tvb, offset, length);
|
|
strbuf = se_alloc(length + 1);
|
|
if (length != 0) {
|
|
memcpy(strbuf, ptr, length);
|
|
}
|
|
strbuf[length] = '\0';
|
|
return strbuf;
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff, an offset, and an encoding, with the offset assumed
|
|
* to refer to a null-terminated string, find the length of that string
|
|
* (and throw an exception if the tvbuff ends before we find the null),
|
|
* allocate a buffer big enough to hold the string, copy the string into
|
|
* it, and return a pointer to the string; if the encoding is EBCDIC, map
|
|
* the string from EBCDIC to ASCII. Also return the length of the
|
|
* string (including the terminating null) through a pointer.
|
|
*/
|
|
guint8 *
|
|
tvb_get_stringz_enc(tvbuff_t *tvb, const gint offset, gint *lengthp, const guint encoding)
|
|
{
|
|
guint size;
|
|
guint8 *strptr;
|
|
|
|
size = tvb_strsize(tvb, offset);
|
|
strptr = g_malloc(size);
|
|
tvb_memcpy(tvb, strptr, offset, size);
|
|
if ((encoding & ENC_CHARENCODING_MASK) == ENC_EBCDIC)
|
|
EBCDIC_to_ASCII(strptr, size);
|
|
if (lengthp)
|
|
*lengthp = size;
|
|
return strptr;
|
|
}
|
|
|
|
guint8 *
|
|
tvb_get_stringz(tvbuff_t *tvb, const gint offset, gint *lengthp)
|
|
{
|
|
return tvb_get_stringz_enc(tvb, offset, lengthp, ENC_UTF_8|ENC_NA);
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff and an offset, with the offset assumed to refer to
|
|
* a null-terminated string, find the length of that string (and throw
|
|
* an exception if the tvbuff ends before we find the null), ensure that
|
|
* the TVB is flat, and return a pointer to the string (in the TVB).
|
|
* Also return the length of the string (including the terminating null)
|
|
* through a pointer.
|
|
*
|
|
* As long as we aren't using composite TVBs, this saves the cycles used
|
|
* (often unnecessariliy) in allocating a buffer and copying the string into
|
|
* it. (If we do start using composite TVBs, we may want to replace this
|
|
* function with the _ephemeral versoin.)
|
|
*/
|
|
const guint8 *
|
|
tvb_get_const_stringz(tvbuff_t *tvb, const gint offset, gint *lengthp)
|
|
{
|
|
guint size;
|
|
const guint8 *strptr;
|
|
|
|
size = tvb_strsize(tvb, offset);
|
|
strptr = ensure_contiguous(tvb, offset, size);
|
|
if (lengthp)
|
|
*lengthp = size;
|
|
return strptr;
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff and an offset, with the offset assumed to refer to
|
|
* a null-terminated string, find the length of that string (and throw
|
|
* an exception if the tvbuff ends before we find the null), allocate
|
|
* a buffer big enough to hold the string, copy the string into it,
|
|
* and return a pointer to the string. Also return the length of the
|
|
* string (including the terminating null) through a pointer.
|
|
*
|
|
* This function allocates memory from a buffer with packet lifetime.
|
|
* You do not have to free this buffer, it will be automatically freed
|
|
* when wireshark starts decoding the next packet.
|
|
* Do not use this function if you want the allocated memory to be persistent
|
|
* after the current packet has been dissected.
|
|
*/
|
|
guint8 *
|
|
tvb_get_ephemeral_stringz_enc(tvbuff_t *tvb, const gint offset, gint *lengthp, const guint encoding)
|
|
{
|
|
guint size;
|
|
guint8 *strptr;
|
|
|
|
switch (encoding & ENC_CHARENCODING_MASK) {
|
|
|
|
case ENC_ASCII:
|
|
default:
|
|
/*
|
|
* For now, we treat bogus values as meaning
|
|
* "ASCII" rather than reporting an error,
|
|
* for the benefit of old dissectors written
|
|
* when the last argument to proto_tree_add_item()
|
|
* was a gboolean for the byte order, not an
|
|
* encoding value, and passed non-zero values
|
|
* other than TRUE to mean "little-endian".
|
|
*
|
|
* XXX - should map all octets with the 8th bit
|
|
* not set to a "substitute" UTF-8 character.
|
|
*/
|
|
strptr = tvb_get_ephemeral_stringz(tvb, offset, lengthp);
|
|
break;
|
|
|
|
case ENC_UTF_8:
|
|
/*
|
|
* XXX - should map all invalid UTF-8 sequences
|
|
* to a "substitute" UTF-8 character.
|
|
*/
|
|
strptr = tvb_get_ephemeral_stringz(tvb, offset, lengthp);
|
|
break;
|
|
|
|
case ENC_UTF_16:
|
|
/*
|
|
* XXX - needs to handle surrogate pairs and to map
|
|
* invalid characters and sequences to a "substitute"
|
|
* UTF-8 character.
|
|
*/
|
|
strptr = tvb_get_ephemeral_unicode_stringz(tvb, offset, lengthp,
|
|
encoding & ENC_LITTLE_ENDIAN);
|
|
break;
|
|
|
|
case ENC_UCS_2:
|
|
/*
|
|
* XXX - needs to map values that are not valid UCS-2
|
|
* characters (such as, I think, values used as the
|
|
* components of a UTF-16 surrogate pair) to a
|
|
* "substitute" UTF-8 character.
|
|
*/
|
|
strptr = tvb_get_ephemeral_unicode_stringz(tvb, offset, lengthp,
|
|
encoding & ENC_LITTLE_ENDIAN);
|
|
break;
|
|
|
|
case ENC_EBCDIC:
|
|
/*
|
|
* XXX - do the copy and conversion in one pass.
|
|
*
|
|
* XXX - multiple "dialects" of EBCDIC?
|
|
*/
|
|
size = tvb_strsize(tvb, offset);
|
|
strptr = ep_alloc(size);
|
|
tvb_memcpy(tvb, strptr, offset, size);
|
|
EBCDIC_to_ASCII(strptr, size);
|
|
if (lengthp)
|
|
*lengthp = size;
|
|
break;
|
|
}
|
|
|
|
return strptr;
|
|
}
|
|
|
|
guint8 *
|
|
tvb_get_ephemeral_stringz(tvbuff_t *tvb, const gint offset, gint *lengthp)
|
|
{
|
|
guint size;
|
|
guint8 *strptr;
|
|
|
|
size = tvb_strsize(tvb, offset);
|
|
strptr = ep_alloc(size);
|
|
tvb_memcpy(tvb, strptr, offset, size);
|
|
if (lengthp)
|
|
*lengthp = size;
|
|
return strptr;
|
|
}
|
|
|
|
/*
|
|
* Unicode (UTF-16) version of tvb_get_ephemeral_stringz()
|
|
*
|
|
* Encoding paramter should be ENC_BIG_ENDIAN or ENC_LITTLE_ENDIAN
|
|
*
|
|
* Returns an ep_ allocated UTF-8 string and updates lengthp pointer with length of string (in bytes)
|
|
*/
|
|
gchar *
|
|
tvb_get_ephemeral_unicode_stringz(tvbuff_t *tvb, const gint offset, gint *lengthp, const guint encoding)
|
|
{
|
|
/* Longest UTF-8 character takes 6 bytes + 1 byte for NUL, round it to 8B */
|
|
gchar tmpbuf[8];
|
|
gunichar2 uchar;
|
|
gint size; /* Number of UTF-16 characters */
|
|
gint i; /* Byte counter for tvbuff */
|
|
gint tmpbuf_len;
|
|
emem_strbuf_t *strbuf = NULL;
|
|
|
|
strbuf = ep_strbuf_new(NULL);
|
|
|
|
size = tvb_unicode_strsize(tvb, offset);
|
|
|
|
for(i = 0; i < size; i += 2) {
|
|
|
|
if (encoding == ENC_BIG_ENDIAN)
|
|
uchar = tvb_get_ntohs(tvb, offset + i);
|
|
else
|
|
uchar = tvb_get_letohs(tvb, offset + i);
|
|
|
|
tmpbuf_len = g_unichar_to_utf8(uchar, tmpbuf);
|
|
|
|
/* NULL terminate the tmpbuf so ep_strbuf_append knows where
|
|
* to stop */
|
|
tmpbuf[tmpbuf_len] = '\0';
|
|
|
|
ep_strbuf_append(strbuf, tmpbuf);
|
|
}
|
|
|
|
if (lengthp)
|
|
*lengthp = i; /* Number of *bytes* processed */
|
|
|
|
return strbuf->str;
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff and an offset, with the offset assumed to refer to
|
|
* a null-terminated string, find the length of that string (and throw
|
|
* an exception if the tvbuff ends before we find the null), allocate
|
|
* a buffer big enough to hold the string, copy the string into it,
|
|
* and return a pointer to the string. Also return the length of the
|
|
* string (including the terminating null) through a pointer.
|
|
*
|
|
* This function allocates memory from a buffer with capture session lifetime.
|
|
* You do not have to free this buffer, it will be automatically freed
|
|
* when wireshark starts or opens a new capture.
|
|
*/
|
|
guint8 *
|
|
tvb_get_seasonal_stringz(tvbuff_t *tvb, const gint offset, gint *lengthp)
|
|
{
|
|
guint size;
|
|
guint8 *strptr;
|
|
|
|
size = tvb_strsize(tvb, offset);
|
|
strptr = se_alloc(size);
|
|
tvb_memcpy(tvb, strptr, offset, size);
|
|
if (lengthp)
|
|
*lengthp = size;
|
|
return strptr;
|
|
}
|
|
|
|
/* Looks for a stringz (NUL-terminated string) in tvbuff and copies
|
|
* no more than bufsize number of bytes, including terminating NUL, to buffer.
|
|
* Returns length of string (not including terminating NUL), or -1 if the string was
|
|
* truncated in the buffer due to not having reached the terminating NUL.
|
|
* In this way, it acts like g_snprintf().
|
|
*
|
|
* bufsize MUST be greater than 0.
|
|
*
|
|
* When processing a packet where the remaining number of bytes is less
|
|
* than bufsize, an exception is not thrown if the end of the packet
|
|
* is reached before the NUL is found. If no NUL is found before reaching
|
|
* the end of the short packet, -1 is still returned, and the string
|
|
* is truncated with a NUL, albeit not at buffer[bufsize - 1], but
|
|
* at the correct spot, terminating the string.
|
|
*
|
|
* *bytes_copied will contain the number of bytes actually copied,
|
|
* including the terminating-NUL.
|
|
*/
|
|
static gint
|
|
_tvb_get_nstringz(tvbuff_t *tvb, const gint offset, const guint bufsize, guint8* buffer, gint *bytes_copied)
|
|
{
|
|
gint stringlen;
|
|
guint abs_offset, junk_length;
|
|
gint limit, len;
|
|
gboolean decreased_max = FALSE;
|
|
|
|
check_offset_length(tvb->length, tvb->reported_length, offset, 0, &abs_offset, &junk_length);
|
|
|
|
/* There must at least be room for the terminating NUL. */
|
|
DISSECTOR_ASSERT(bufsize != 0);
|
|
|
|
/* If there's no room for anything else, just return the NUL. */
|
|
if (bufsize == 1) {
|
|
buffer[0] = 0;
|
|
*bytes_copied = 1;
|
|
return 0;
|
|
}
|
|
|
|
/* Only read to end of tvbuff, w/o throwing exception. */
|
|
len = tvb_length_remaining(tvb, abs_offset);
|
|
|
|
/* check_offset_length() won't throw an exception if we're
|
|
* looking at the byte immediately after the end of the tvbuff. */
|
|
if (len == 0) {
|
|
THROW(ReportedBoundsError);
|
|
}
|
|
|
|
/* This should not happen because check_offset_length() would
|
|
* have already thrown an exception if 'offset' were out-of-bounds.
|
|
*/
|
|
DISSECTOR_ASSERT(len != -1);
|
|
|
|
/*
|
|
* If we've been passed a negative number, bufsize will
|
|
* be huge.
|
|
*/
|
|
DISSECTOR_ASSERT(bufsize <= G_MAXINT);
|
|
|
|
if ((guint)len < bufsize) {
|
|
limit = len;
|
|
decreased_max = TRUE;
|
|
}
|
|
else {
|
|
limit = bufsize;
|
|
}
|
|
|
|
stringlen = tvb_strnlen(tvb, abs_offset, limit - 1);
|
|
/* If NUL wasn't found, copy the data and return -1 */
|
|
if (stringlen == -1) {
|
|
tvb_memcpy(tvb, buffer, abs_offset, limit);
|
|
if (decreased_max) {
|
|
buffer[limit] = 0;
|
|
/* Add 1 for the extra NUL that we set at buffer[limit],
|
|
* pretending that it was copied as part of the string. */
|
|
*bytes_copied = limit + 1;
|
|
}
|
|
else {
|
|
*bytes_copied = limit;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
/* Copy the string to buffer */
|
|
tvb_memcpy(tvb, buffer, abs_offset, stringlen + 1);
|
|
*bytes_copied = stringlen + 1;
|
|
return stringlen;
|
|
}
|
|
|
|
/* Looks for a stringz (NUL-terminated string) in tvbuff and copies
|
|
* no more than bufsize number of bytes, including terminating NUL, to buffer.
|
|
* Returns length of string (not including terminating NUL), or -1 if the string was
|
|
* truncated in the buffer due to not having reached the terminating NUL.
|
|
* In this way, it acts like g_snprintf().
|
|
*
|
|
* When processing a packet where the remaining number of bytes is less
|
|
* than bufsize, an exception is not thrown if the end of the packet
|
|
* is reached before the NUL is found. If no NUL is found before reaching
|
|
* the end of the short packet, -1 is still returned, and the string
|
|
* is truncated with a NUL, albeit not at buffer[bufsize - 1], but
|
|
* at the correct spot, terminating the string.
|
|
*/
|
|
gint
|
|
tvb_get_nstringz(tvbuff_t *tvb, const gint offset, const guint bufsize, guint8* buffer)
|
|
{
|
|
gint bytes_copied;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
return _tvb_get_nstringz(tvb, offset, bufsize, buffer, &bytes_copied);
|
|
}
|
|
|
|
/* Like tvb_get_nstringz(), but never returns -1. The string is guaranteed to
|
|
* have a terminating NUL. If the string was truncated when copied into buffer,
|
|
* a NUL is placed at the end of buffer to terminate it.
|
|
*/
|
|
gint
|
|
tvb_get_nstringz0(tvbuff_t *tvb, const gint offset, const guint bufsize, guint8* buffer)
|
|
{
|
|
gint len, bytes_copied;
|
|
|
|
DISSECTOR_ASSERT(tvb && tvb->initialized);
|
|
|
|
len = _tvb_get_nstringz(tvb, offset, bufsize, buffer, &bytes_copied);
|
|
|
|
if (len == -1) {
|
|
buffer[bufsize - 1] = 0;
|
|
return bytes_copied - 1;
|
|
}
|
|
else {
|
|
return len;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff, an offset into the tvbuff, and a length that starts
|
|
* at that offset (which may be -1 for "all the way to the end of the
|
|
* tvbuff"), find the end of the (putative) line that starts at the
|
|
* specified offset in the tvbuff, going no further than the specified
|
|
* length.
|
|
*
|
|
* Return the length of the line (not counting the line terminator at
|
|
* the end), or, if we don't find a line terminator:
|
|
*
|
|
* if "deseg" is true, return -1;
|
|
*
|
|
* if "deseg" is false, return the amount of data remaining in
|
|
* the buffer.
|
|
*
|
|
* Set "*next_offset" to the offset of the character past the line
|
|
* terminator, or past the end of the buffer if we don't find a line
|
|
* terminator. (It's not set if we return -1.)
|
|
*/
|
|
gint
|
|
tvb_find_line_end(tvbuff_t *tvb, const gint offset, int len, gint *next_offset, const gboolean desegment)
|
|
{
|
|
gint eob_offset;
|
|
gint eol_offset;
|
|
int linelen;
|
|
guchar found_needle = 0;
|
|
|
|
if (len == -1)
|
|
len = tvb_length_remaining(tvb, offset);
|
|
/*
|
|
* XXX - what if "len" is still -1, meaning "offset is past the
|
|
* end of the tvbuff"?
|
|
*/
|
|
eob_offset = offset + len;
|
|
|
|
/*
|
|
* Look either for a CR or an LF.
|
|
*/
|
|
eol_offset = tvb_pbrk_guint8(tvb, offset, len, "\r\n", &found_needle);
|
|
if (eol_offset == -1) {
|
|
/*
|
|
* No CR or LF - line is presumably continued in next packet.
|
|
*/
|
|
if (desegment) {
|
|
/*
|
|
* Tell our caller we saw no EOL, so they can
|
|
* try to desegment and get the entire line
|
|
* into one tvbuff.
|
|
*/
|
|
return -1;
|
|
} else {
|
|
/*
|
|
* Pretend the line runs to the end of the tvbuff.
|
|
*/
|
|
linelen = eob_offset - offset;
|
|
if (next_offset)
|
|
*next_offset = eob_offset;
|
|
}
|
|
} else {
|
|
/*
|
|
* Find the number of bytes between the starting offset
|
|
* and the CR or LF.
|
|
*/
|
|
linelen = eol_offset - offset;
|
|
|
|
/*
|
|
* Is it a CR?
|
|
*/
|
|
if (found_needle == '\r') {
|
|
/*
|
|
* Yes - is it followed by an LF?
|
|
*/
|
|
if (eol_offset + 1 >= eob_offset) {
|
|
/*
|
|
* Dunno - the next byte isn't in this
|
|
* tvbuff.
|
|
*/
|
|
if (desegment) {
|
|
/*
|
|
* We'll return -1, although that
|
|
* runs the risk that if the line
|
|
* really *is* terminated with a CR,
|
|
* we won't properly dissect this
|
|
* tvbuff.
|
|
*
|
|
* It's probably more likely that
|
|
* the line ends with CR-LF than
|
|
* that it ends with CR by itself.
|
|
*/
|
|
return -1;
|
|
}
|
|
} else {
|
|
/*
|
|
* Well, we can at least look at the next
|
|
* byte.
|
|
*/
|
|
if (tvb_get_guint8(tvb, eol_offset + 1) == '\n') {
|
|
/*
|
|
* It's an LF; skip over the CR.
|
|
*/
|
|
eol_offset++;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Return the offset of the character after the last
|
|
* character in the line, skipping over the last character
|
|
* in the line terminator.
|
|
*/
|
|
if (next_offset)
|
|
*next_offset = eol_offset + 1;
|
|
}
|
|
return linelen;
|
|
}
|
|
|
|
/*
|
|
* Given a tvbuff, an offset into the tvbuff, and a length that starts
|
|
* at that offset (which may be -1 for "all the way to the end of the
|
|
* tvbuff"), find the end of the (putative) line that starts at the
|
|
* specified offset in the tvbuff, going no further than the specified
|
|
* length.
|
|
*
|
|
* However, treat quoted strings inside the buffer specially - don't
|
|
* treat newlines in quoted strings as line terminators.
|
|
*
|
|
* Return the length of the line (not counting the line terminator at
|
|
* the end), or the amount of data remaining in the buffer if we don't
|
|
* find a line terminator.
|
|
*
|
|
* Set "*next_offset" to the offset of the character past the line
|
|
* terminator, or past the end of the buffer if we don't find a line
|
|
* terminator.
|
|
*/
|
|
gint
|
|
tvb_find_line_end_unquoted(tvbuff_t *tvb, const gint offset, int len, gint *next_offset)
|
|
{
|
|
gint cur_offset, char_offset;
|
|
gboolean is_quoted;
|
|
guchar c = 0;
|
|
gint eob_offset;
|
|
int linelen;
|
|
|
|
if (len == -1)
|
|
len = tvb_length_remaining(tvb, offset);
|
|
/*
|
|
* XXX - what if "len" is still -1, meaning "offset is past the
|
|
* end of the tvbuff"?
|
|
*/
|
|
eob_offset = offset + len;
|
|
|
|
cur_offset = offset;
|
|
is_quoted = FALSE;
|
|
for (;;) {
|
|
/*
|
|
* Is this part of the string quoted?
|
|
*/
|
|
if (is_quoted) {
|
|
/*
|
|
* Yes - look only for the terminating quote.
|
|
*/
|
|
char_offset = tvb_find_guint8(tvb, cur_offset, len,
|
|
'"');
|
|
} else {
|
|
/*
|
|
* Look either for a CR, an LF, or a '"'.
|
|
*/
|
|
char_offset = tvb_pbrk_guint8(tvb, cur_offset, len, "\r\n\"", &c);
|
|
}
|
|
if (char_offset == -1) {
|
|
/*
|
|
* Not found - line is presumably continued in
|
|
* next packet.
|
|
* We pretend the line runs to the end of the tvbuff.
|
|
*/
|
|
linelen = eob_offset - offset;
|
|
if (next_offset)
|
|
*next_offset = eob_offset;
|
|
break;
|
|
}
|
|
|
|
if (is_quoted) {
|
|
/*
|
|
* We're processing a quoted string.
|
|
* We only looked for ", so we know it's a ";
|
|
* as we're processing a quoted string, it's a
|
|
* closing quote.
|
|
*/
|
|
is_quoted = FALSE;
|
|
} else {
|
|
/*
|
|
* OK, what is it?
|
|
*/
|
|
if (c == '"') {
|
|
/*
|
|
* Un-quoted "; it begins a quoted
|
|
* string.
|
|
*/
|
|
is_quoted = TRUE;
|
|
} else {
|
|
/*
|
|
* It's a CR or LF; we've found a line
|
|
* terminator.
|
|
*
|
|
* Find the number of bytes between the
|
|
* starting offset and the CR or LF.
|
|
*/
|
|
linelen = char_offset - offset;
|
|
|
|
/*
|
|
* Is it a CR?
|
|
*/
|
|
if (c == '\r') {
|
|
/*
|
|
* Yes; is it followed by an LF?
|
|
*/
|
|
if (char_offset + 1 < eob_offset &&
|
|
tvb_get_guint8(tvb, char_offset + 1)
|
|
== '\n') {
|
|
/*
|
|
* Yes; skip over the CR.
|
|
*/
|
|
char_offset++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Return the offset of the character after
|
|
* the last character in the line, skipping
|
|
* over the last character in the line
|
|
* terminator, and quit.
|
|
*/
|
|
if (next_offset)
|
|
*next_offset = char_offset + 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Step past the character we found.
|
|
*/
|
|
cur_offset = char_offset + 1;
|
|
if (cur_offset >= eob_offset) {
|
|
/*
|
|
* The character we found was the last character
|
|
* in the tvbuff - line is presumably continued in
|
|
* next packet.
|
|
* We pretend the line runs to the end of the tvbuff.
|
|
*/
|
|
linelen = eob_offset - offset;
|
|
if (next_offset)
|
|
*next_offset = eob_offset;
|
|
break;
|
|
}
|
|
}
|
|
return linelen;
|
|
}
|
|
|
|
/*
|
|
* Copied from the mgcp dissector. (This function should be moved to /epan )
|
|
* tvb_skip_wsp - Returns the position in tvb of the first non-whitespace
|
|
* character following offset or offset + maxlength -1 whichever
|
|
* is smaller.
|
|
*
|
|
* Parameters:
|
|
* tvb - The tvbuff in which we are skipping whitespace.
|
|
* offset - The offset in tvb from which we begin trying to skip whitespace.
|
|
* maxlength - The maximum distance from offset that we may try to skip
|
|
* whitespace.
|
|
*
|
|
* Returns: The position in tvb of the first non-whitespace
|
|
* character following offset or offset + maxlength -1 whichever
|
|
* is smaller.
|
|
*/
|
|
gint
|
|
tvb_skip_wsp(tvbuff_t *tvb, const gint offset, const gint maxlength)
|
|
{
|
|
gint counter = offset;
|
|
gint end, tvb_len;
|
|
guint8 tempchar;
|
|
|
|
/* Get the length remaining */
|
|
tvb_len = tvb_length(tvb);
|
|
end = offset + maxlength;
|
|
if (end >= tvb_len)
|
|
{
|
|
end = tvb_len;
|
|
}
|
|
|
|
/* Skip past spaces, tabs, CRs and LFs until run out or meet something else */
|
|
for (counter = offset;
|
|
counter < end &&
|
|
((tempchar = tvb_get_guint8(tvb,counter)) == ' ' ||
|
|
tempchar == '\t' || tempchar == '\r' || tempchar == '\n');
|
|
counter++);
|
|
|
|
return (counter);
|
|
}
|
|
|
|
gint
|
|
tvb_skip_wsp_return(tvbuff_t *tvb, const gint offset) {
|
|
gint counter = offset;
|
|
gint end;
|
|
guint8 tempchar;
|
|
end = 0;
|
|
|
|
for(counter = offset; counter > end &&
|
|
((tempchar = tvb_get_guint8(tvb,counter)) == ' ' ||
|
|
tempchar == '\t' || tempchar == '\n' || tempchar == '\r'); counter--);
|
|
counter++;
|
|
return (counter);
|
|
}
|
|
|
|
|
|
/*
|
|
* Format a bunch of data from a tvbuff as bytes, returning a pointer
|
|
* to the string with the formatted data, with "punct" as a byte
|
|
* separator.
|
|
*/
|
|
gchar *
|
|
tvb_bytes_to_str_punct(tvbuff_t *tvb, const gint offset, const gint len, const gchar punct)
|
|
{
|
|
return bytes_to_str_punct(ensure_contiguous(tvb, offset, len), len, punct);
|
|
}
|
|
|
|
|
|
/*
|
|
* Given a tvbuff, an offset into the tvbuff, and a length that starts
|
|
* at that offset (which may be -1 for "all the way to the end of the
|
|
* tvbuff"), fetch BCD encoded digits from a tvbuff starting from either
|
|
* the low or high half byte, formating the digits according to an input digit set,
|
|
* if NUll a default digit set of 0-9 returning "?" for overdecadic digits will be used.
|
|
* A pointer to the EP allocated string will be returned.
|
|
* Note a tvbuff content of 0xf is considered a 'filler' and will end the conversion.
|
|
*/
|
|
static dgt_set_t Dgt1_9_bcd = {
|
|
{
|
|
/* 0 1 2 3 4 5 6 7 8 9 a b c d e */
|
|
'0','1','2','3','4','5','6','7','8','9','?','?','?','?','?'
|
|
}
|
|
};
|
|
const gchar *
|
|
tvb_bcd_dig_to_ep_str(tvbuff_t *tvb, const gint offset, const gint len, dgt_set_t *dgt, gboolean skip_first)
|
|
{
|
|
int length;
|
|
guint8 octet;
|
|
int i = 0;
|
|
char *digit_str;
|
|
gint t_offset = offset;
|
|
|
|
if (!dgt)
|
|
dgt = &Dgt1_9_bcd;
|
|
|
|
if (len == -1) {
|
|
length = tvb_length(tvb);
|
|
if (length < offset) {
|
|
return "";
|
|
}
|
|
} else {
|
|
length = offset + len;
|
|
}
|
|
digit_str = ep_alloc((length - offset)*2+1);
|
|
|
|
while (t_offset < length) {
|
|
|
|
octet = tvb_get_guint8(tvb,t_offset);
|
|
if (!skip_first) {
|
|
digit_str[i] = dgt->out[octet & 0x0f];
|
|
i++;
|
|
}
|
|
skip_first = FALSE;
|
|
|
|
/*
|
|
* unpack second value in byte
|
|
*/
|
|
octet = octet >> 4;
|
|
|
|
if (octet == 0x0f) /* odd number bytes - hit filler */
|
|
break;
|
|
|
|
digit_str[i] = dgt->out[octet & 0x0f];
|
|
i++;
|
|
t_offset++;
|
|
|
|
}
|
|
digit_str[i]= '\0';
|
|
return digit_str;
|
|
|
|
}
|
|
|
|
/*
|
|
* Format a bunch of data from a tvbuff as bytes, returning a pointer
|
|
* to the string with the formatted data.
|
|
*/
|
|
gchar *
|
|
tvb_bytes_to_str(tvbuff_t *tvb, const gint offset, const gint len)
|
|
{
|
|
return bytes_to_str(ensure_contiguous(tvb, offset, len), len);
|
|
}
|
|
|
|
/* Find a needle tvbuff within a haystack tvbuff. */
|
|
gint
|
|
tvb_find_tvb(tvbuff_t *haystack_tvb, tvbuff_t *needle_tvb, const gint haystack_offset)
|
|
{
|
|
guint haystack_abs_offset, haystack_abs_length;
|
|
const guint8 *haystack_data;
|
|
const guint8 *needle_data;
|
|
const guint needle_len = needle_tvb->length;
|
|
const guint8 *location;
|
|
|
|
DISSECTOR_ASSERT(haystack_tvb && haystack_tvb->initialized);
|
|
|
|
if (haystack_tvb->length < 1 || needle_tvb->length < 1) {
|
|
return -1;
|
|
}
|
|
|
|
/* Get pointers to the tvbuffs' data. */
|
|
haystack_data = ensure_contiguous(haystack_tvb, 0, -1);
|
|
needle_data = ensure_contiguous(needle_tvb, 0, -1);
|
|
|
|
check_offset_length(haystack_tvb->length, haystack_tvb->reported_length, haystack_offset, -1,
|
|
&haystack_abs_offset, &haystack_abs_length);
|
|
|
|
location = epan_memmem(haystack_data + haystack_abs_offset, haystack_abs_length,
|
|
needle_data, needle_len);
|
|
|
|
if (location) {
|
|
return (gint) (location - haystack_data);
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
#ifdef HAVE_LIBZ
|
|
/*
|
|
* Uncompresses a zlib compressed packet inside a message of tvb at offset with
|
|
* length comprlen. Returns an uncompressed tvbuffer if uncompression
|
|
* succeeded or NULL if uncompression failed.
|
|
*/
|
|
#define TVB_Z_MIN_BUFSIZ 32768
|
|
#define TVB_Z_MAX_BUFSIZ 1048576 * 10
|
|
/* #define TVB_Z_DEBUG 1 */
|
|
#undef TVB_Z_DEBUG
|
|
|
|
tvbuff_t *
|
|
tvb_uncompress(tvbuff_t *tvb, const int offset, int comprlen)
|
|
{
|
|
gint err = Z_OK;
|
|
guint bytes_out = 0;
|
|
guint8 *compr = NULL;
|
|
guint8 *uncompr = NULL;
|
|
tvbuff_t *uncompr_tvb = NULL;
|
|
z_streamp strm = NULL;
|
|
Bytef *strmbuf = NULL;
|
|
guint inits_done = 0;
|
|
gint wbits = MAX_WBITS;
|
|
guint8 *next = NULL;
|
|
guint bufsiz = TVB_Z_MIN_BUFSIZ;
|
|
#ifdef TVB_Z_DEBUG
|
|
guint inflate_passes = 0;
|
|
guint bytes_in = tvb_length_remaining(tvb, offset);
|
|
#endif
|
|
|
|
if (tvb == NULL) {
|
|
return NULL;
|
|
}
|
|
|
|
compr = tvb_memdup(tvb, offset, comprlen);
|
|
|
|
if (!compr)
|
|
return NULL;
|
|
|
|
/*
|
|
* Assume that the uncompressed data is at least twice as big as
|
|
* the compressed size.
|
|
*/
|
|
bufsiz = tvb_length_remaining(tvb, offset) * 2;
|
|
bufsiz = CLAMP(bufsiz, TVB_Z_MIN_BUFSIZ, TVB_Z_MAX_BUFSIZ);
|
|
|
|
#ifdef TVB_Z_DEBUG
|
|
printf("bufsiz: %u bytes\n", bufsiz);
|
|
#endif
|
|
|
|
next = compr;
|
|
|
|
strm = g_new0(z_stream, 1);
|
|
strm->next_in = next;
|
|
strm->avail_in = comprlen;
|
|
|
|
strmbuf = g_malloc0(bufsiz);
|
|
strm->next_out = strmbuf;
|
|
strm->avail_out = bufsiz;
|
|
|
|
err = inflateInit2(strm, wbits);
|
|
inits_done = 1;
|
|
if (err != Z_OK) {
|
|
inflateEnd(strm);
|
|
g_free(strm);
|
|
g_free(compr);
|
|
g_free(strmbuf);
|
|
return NULL;
|
|
}
|
|
|
|
while (1) {
|
|
memset(strmbuf, '\0', bufsiz);
|
|
strm->next_out = strmbuf;
|
|
strm->avail_out = bufsiz;
|
|
|
|
err = inflate(strm, Z_SYNC_FLUSH);
|
|
|
|
if (err == Z_OK || err == Z_STREAM_END) {
|
|
guint bytes_pass = bufsiz - strm->avail_out;
|
|
|
|
#ifdef TVB_Z_DEBUG
|
|
++inflate_passes;
|
|
#endif
|
|
|
|
if (uncompr == NULL) {
|
|
/*
|
|
* This is ugly workaround for bug #6480
|
|
* (https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=6480)
|
|
*
|
|
* g_memdup(..., 0) returns NULL (g_malloc(0) also)
|
|
* when uncompr is NULL logic below doesn't create tvb
|
|
* which is later interpreted as decompression failed.
|
|
*/
|
|
uncompr = (bytes_pass || err != Z_STREAM_END) ?
|
|
g_memdup(strmbuf, bytes_pass) :
|
|
g_strdup("");
|
|
} else {
|
|
guint8 *new_data = g_malloc0(bytes_out + bytes_pass);
|
|
|
|
memcpy(new_data, uncompr, bytes_out);
|
|
memcpy(new_data + bytes_out, strmbuf, bytes_pass);
|
|
|
|
g_free(uncompr);
|
|
uncompr = new_data;
|
|
}
|
|
|
|
bytes_out += bytes_pass;
|
|
|
|
if (err == Z_STREAM_END) {
|
|
inflateEnd(strm);
|
|
g_free(strm);
|
|
g_free(strmbuf);
|
|
break;
|
|
}
|
|
} else if (err == Z_BUF_ERROR) {
|
|
/*
|
|
* It's possible that not enough frames were captured
|
|
* to decompress this fully, so return what we've done
|
|
* so far, if any.
|
|
*/
|
|
inflateEnd(strm);
|
|
g_free(strm);
|
|
g_free(strmbuf);
|
|
|
|
if (uncompr != NULL) {
|
|
break;
|
|
} else {
|
|
g_free(compr);
|
|
return NULL;
|
|
}
|
|
|
|
} else if (err == Z_DATA_ERROR && inits_done == 1
|
|
&& uncompr == NULL && (*compr == 0x1f) &&
|
|
(*(compr + 1) == 0x8b)) {
|
|
/*
|
|
* inflate() is supposed to handle both gzip and deflate
|
|
* streams automatically, but in reality it doesn't
|
|
* seem to handle either (at least not within the
|
|
* context of an HTTP response.) We have to try
|
|
* several tweaks, depending on the type of data and
|
|
* version of the library installed.
|
|
*/
|
|
|
|
/*
|
|
* Gzip file format. Skip past the header, since the
|
|
* fix to make it work (setting windowBits to 31)
|
|
* doesn't work with all versions of the library.
|
|
*/
|
|
Bytef *c = compr + 2;
|
|
Bytef flags = 0;
|
|
|
|
if (*c == Z_DEFLATED) {
|
|
c++;
|
|
} else {
|
|
inflateEnd(strm);
|
|
g_free(strm);
|
|
g_free(compr);
|
|
g_free(strmbuf);
|
|
return NULL;
|
|
}
|
|
|
|
flags = *c;
|
|
|
|
/* Skip past the MTIME, XFL, and OS fields. */
|
|
c += 7;
|
|
|
|
if (flags & (1 << 2)) {
|
|
/* An Extra field is present. */
|
|
gint xsize = (gint)(*c |
|
|
(*(c + 1) << 8));
|
|
|
|
c += xsize;
|
|
}
|
|
|
|
if (flags & (1 << 3)) {
|
|
/* A null terminated filename */
|
|
|
|
while ((c - compr) < comprlen && *c != '\0') {
|
|
c++;
|
|
}
|
|
|
|
c++;
|
|
}
|
|
|
|
if (flags & (1 << 4)) {
|
|
/* A null terminated comment */
|
|
|
|
while ((c - compr) < comprlen && *c != '\0') {
|
|
c++;
|
|
}
|
|
|
|
c++;
|
|
}
|
|
|
|
|
|
inflateReset(strm);
|
|
next = c;
|
|
strm->next_in = next;
|
|
if (c - compr > comprlen) {
|
|
inflateEnd(strm);
|
|
g_free(strm);
|
|
g_free(compr);
|
|
g_free(strmbuf);
|
|
return NULL;
|
|
}
|
|
comprlen -= (int) (c - compr);
|
|
|
|
inflateEnd(strm);
|
|
inflateInit2(strm, wbits);
|
|
inits_done++;
|
|
} else if (err == Z_DATA_ERROR && uncompr == NULL &&
|
|
inits_done <= 3) {
|
|
|
|
/*
|
|
* Re-init the stream with a negative
|
|
* MAX_WBITS. This is necessary due to
|
|
* some servers (Apache) not sending
|
|
* the deflate header with the
|
|
* content-encoded response.
|
|
*/
|
|
wbits = -MAX_WBITS;
|
|
|
|
inflateReset(strm);
|
|
|
|
strm->next_in = next;
|
|
strm->avail_in = comprlen;
|
|
|
|
inflateEnd(strm);
|
|
memset(strmbuf, '\0', bufsiz);
|
|
strm->next_out = strmbuf;
|
|
strm->avail_out = bufsiz;
|
|
|
|
err = inflateInit2(strm, wbits);
|
|
|
|
inits_done++;
|
|
|
|
if (err != Z_OK) {
|
|
g_free(strm);
|
|
g_free(strmbuf);
|
|
g_free(compr);
|
|
g_free(uncompr);
|
|
|
|
return NULL;
|
|
}
|
|
} else {
|
|
inflateEnd(strm);
|
|
g_free(strm);
|
|
g_free(strmbuf);
|
|
|
|
if (uncompr == NULL) {
|
|
g_free(compr);
|
|
return NULL;
|
|
}
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
#ifdef TVB_Z_DEBUG
|
|
printf("inflate() total passes: %u\n", inflate_passes);
|
|
printf("bytes in: %u\nbytes out: %u\n\n", bytes_in, bytes_out);
|
|
#endif
|
|
|
|
if (uncompr != NULL) {
|
|
uncompr_tvb = tvb_new_real_data((guint8*) uncompr, bytes_out, bytes_out);
|
|
tvb_set_free_cb(uncompr_tvb, g_free);
|
|
}
|
|
g_free(compr);
|
|
return uncompr_tvb;
|
|
}
|
|
#else
|
|
tvbuff_t *
|
|
tvb_uncompress(tvbuff_t *tvb _U_, const int offset _U_, int comprlen _U_)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
tvbuff_t *
|
|
tvb_child_uncompress(tvbuff_t *parent, tvbuff_t *tvb, const int offset, int comprlen)
|
|
{
|
|
tvbuff_t *new_tvb = tvb_uncompress(tvb, offset, comprlen);
|
|
if (new_tvb)
|
|
tvb_set_child_real_data_tvbuff (parent, new_tvb);
|
|
return new_tvb;
|
|
}
|
|
|
|
gint
|
|
tvb_raw_offset(tvbuff_t *tvb)
|
|
{
|
|
return ((tvb->raw_offset==-1)?(tvb->raw_offset = tvb_offset_from_real_beginning(tvb)):tvb->raw_offset);
|
|
}
|
|
|
|
struct tvbuff *
|
|
tvb_get_ds_tvb(tvbuff_t *tvb)
|
|
{
|
|
return(tvb->ds_tvb);
|
|
}
|