![Jeff Morriss](/assets/img/avatar_default.png)
make Save-As/Displayed/All-Packets save not only the displayed packets but also any other packets needed (e.g., for reassembly) to fully dissect the displayed packets. This works only for the "All packets" case; choosing only the Selected packet, the Marked packets, or a range of packets would require actually storing which packets depend on which (too much memory) or going through the packet list many times (too slow). Also, this behavior is always the case: you can't save the displayed packets without their dependencies (I don't see why this would be desirable). So far this is done for SCTP and things using the reassembly routines (TCP has been tested). The Win32 dialog was modified but hasn't been tested yet. One confusing aspect of the UI is that the Displayed count in the Save-As dialog does not match the number of displayed packets. (I tried renaming the button "Displayed + Dependencies" but it looked too big.) The tooltip tries to explain this and the fact that this works only in the All-Packets case; suggestions for improvement are welcome. Implementation details: Dissectors (or the reassembly code) can list frames which were needed to build the current frame's tree. If the current frame passes the display filter then each listed frame is marked as "depended upon" (this takes up the last free frame_data flag). When performing a Save-As/Displayed/All-Packets then choose packets which passed the dfilter _or_ are depended upon. svn path=/trunk/; revision=41216
2108 lines
59 KiB
C
2108 lines
59 KiB
C
/* reassemble.c
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* Routines for {fragment,segment} reassembly
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*
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* $Id$
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#ifdef HAVE_CONFIG_H
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# include "config.h"
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#endif
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#include <string.h>
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#include <epan/packet.h>
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#include <epan/reassemble.h>
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#include <epan/emem.h>
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#include <epan/dissectors/packet-dcerpc.h>
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typedef struct _fragment_key {
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address src;
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address dst;
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guint32 id;
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} fragment_key;
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typedef struct _dcerpc_fragment_key {
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address src;
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address dst;
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guint32 id;
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e_uuid_t act_id;
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} dcerpc_fragment_key;
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static void LINK_FRAG(fragment_data *fd_head,fragment_data *fd)
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{
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fragment_data *fd_i;
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/* add fragment to list, keep list sorted */
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for(fd_i= fd_head; fd_i->next;fd_i=fd_i->next) {
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if (fd->offset < fd_i->next->offset )
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break;
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}
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fd->next=fd_i->next;
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fd_i->next=fd;
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}
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/* copy a fragment key to heap store to insert in the hash */
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static void *fragment_key_copy(const void *k)
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{
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const fragment_key* key = (const fragment_key*) k;
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fragment_key *new_key = g_slice_new(fragment_key);
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COPY_ADDRESS(&new_key->src, &key->src);
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COPY_ADDRESS(&new_key->dst, &key->dst);
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new_key->id = key->id;
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return new_key;
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}
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/* copy a dcerpc fragment key to heap store to insert in the hash */
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static void *dcerpc_fragment_key_copy(const void *k)
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{
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const dcerpc_fragment_key* key = (const dcerpc_fragment_key*) k;
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dcerpc_fragment_key *new_key = g_slice_new(dcerpc_fragment_key);
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COPY_ADDRESS(&new_key->src, &key->src);
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COPY_ADDRESS(&new_key->dst, &key->dst);
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new_key->id = key->id;
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new_key->act_id = key->act_id;
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return new_key;
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}
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static gint
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fragment_equal(gconstpointer k1, gconstpointer k2)
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{
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const fragment_key* key1 = (const fragment_key*) k1;
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const fragment_key* key2 = (const fragment_key*) k2;
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/*key.id is the first item to compare since item is most
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likely to differ between sessions, thus shortcircuiting
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the comparasion of addresses.
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*/
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return ( ( (key1->id == key2->id) &&
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(ADDRESSES_EQUAL(&key1->src, &key2->src)) &&
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(ADDRESSES_EQUAL(&key1->dst, &key2->dst))
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) ?
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TRUE : FALSE);
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}
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static guint
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fragment_hash(gconstpointer k)
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{
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const fragment_key* key = (const fragment_key*) k;
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guint hash_val;
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/*
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int i;
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*/
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hash_val = 0;
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/* More than likely: in most captures src and dst addresses are the
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same, and would hash the same.
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We only use id as the hash as an optimization.
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for (i = 0; i < key->src.len; i++)
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hash_val += key->src.data[i];
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for (i = 0; i < key->dst.len; i++)
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hash_val += key->dst.data[i];
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*/
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hash_val += key->id;
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return hash_val;
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}
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static gint
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dcerpc_fragment_equal(gconstpointer k1, gconstpointer k2)
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{
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const dcerpc_fragment_key* key1 = (const dcerpc_fragment_key*) k1;
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const dcerpc_fragment_key* key2 = (const dcerpc_fragment_key*) k2;
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/*key.id is the first item to compare since item is most
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likely to differ between sessions, thus shortcircuiting
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the comparison of addresses.
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*/
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return (((key1->id == key2->id)
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&& (ADDRESSES_EQUAL(&key1->src, &key2->src))
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&& (ADDRESSES_EQUAL(&key1->dst, &key2->dst))
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&& (memcmp (&key1->act_id, &key2->act_id, sizeof (e_uuid_t)) == 0))
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? TRUE : FALSE);
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}
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static guint
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dcerpc_fragment_hash(gconstpointer k)
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{
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const dcerpc_fragment_key* key = (const dcerpc_fragment_key*) k;
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guint hash_val;
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hash_val = 0;
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hash_val += key->id;
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hash_val += key->act_id.Data1;
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hash_val += key->act_id.Data2 << 16;
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hash_val += key->act_id.Data3;
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return hash_val;
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}
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typedef struct _reassembled_key {
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guint32 id;
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guint32 frame;
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} reassembled_key;
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static gint
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reassembled_equal(gconstpointer k1, gconstpointer k2)
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{
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const reassembled_key* key1 = (const reassembled_key*) k1;
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const reassembled_key* key2 = (const reassembled_key*) k2;
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/*
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* We assume that the frame numbers are unlikely to be equal,
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* so we check them first.
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*/
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return key1->frame == key2->frame && key1->id == key2->id;
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}
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static guint
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reassembled_hash(gconstpointer k)
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{
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const reassembled_key* key = (const reassembled_key*) k;
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return key->frame;
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}
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/*
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* For a fragment hash table entry, free the associated fragments.
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* The entry value (fd_chain) is freed herein and the entry is freed
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* when fragment_free_key() [or dcerpc_fragment_free_key()] is called
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* (as a consequence of returning TRUE from this function).
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*/
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static gboolean
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free_all_fragments(gpointer key_arg _U_, gpointer value, gpointer user_data _U_)
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{
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fragment_data *fd_head, *tmp_fd;
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/* g_hash_table_new_full() was used to supply a function
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* to free the key and the addresses.
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*/
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for (fd_head = value; fd_head != NULL; fd_head = tmp_fd) {
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tmp_fd=fd_head->next;
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if(fd_head->data && !(fd_head->flags&FD_NOT_MALLOCED))
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g_free(fd_head->data);
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g_slice_free(fragment_data, fd_head);
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}
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return TRUE;
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}
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/* ------------------------- */
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static fragment_data *new_head(const guint32 flags)
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{
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fragment_data *fd_head;
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/* If head/first structure in list only holds no other data than
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* 'datalen' then we don't have to change the head of the list
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* even if we want to keep it sorted
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*/
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fd_head=g_slice_new0(fragment_data);
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fd_head->flags=flags;
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return fd_head;
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}
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/*
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* For a reassembled-packet hash table entry, free the fragment data
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* to which the value refers.
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*/
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static gboolean
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free_all_reassembled_fragments(gpointer key_arg _U_, gpointer value,
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gpointer user_data _U_)
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{
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fragment_data *fd_head;
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for (fd_head = value; fd_head != NULL; fd_head = fd_head->next) {
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if(fd_head->data && !(fd_head->flags&FD_NOT_MALLOCED)) {
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g_free(fd_head->data);
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/*
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* A reassembled packet is inserted into the
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* hash table once for every frame that made
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* up the reassembled packet; clear the data
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* pointer so that we only free the data the
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* first time we see it.
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*/
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fd_head->data = NULL;
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}
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}
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return TRUE;
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}
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static void
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fragment_free_key(void *ptr)
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{
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fragment_key *key = (fragment_key *)ptr;
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if(key){
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/*
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* Free up the copies of the addresses from the old key.
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*/
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g_free((gpointer)key->src.data);
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g_free((gpointer)key->dst.data);
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g_slice_free(fragment_key, key);
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}
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}
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static void
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dcerpc_fragment_free_key(void *ptr)
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{
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dcerpc_fragment_key *key = (dcerpc_fragment_key *)ptr;
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if(key){
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/*
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* Free up the copies of the addresses from the old key.
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*/
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g_free((gpointer)key->src.data);
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g_free((gpointer)key->dst.data);
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g_slice_free(dcerpc_fragment_key, key);
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}
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}
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/*
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* Initialize a fragment table.
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*/
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void
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fragment_table_init(GHashTable **fragment_table)
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{
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if (*fragment_table != NULL) {
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/*
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* The fragment hash table exists.
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*
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* Remove all entries and free fragment data for each entry.
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*
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* If slices are used (GLIB >= 2.10)
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* the keys are freed by calling fragment_free_key()
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* and the values are freed in free_all_fragments().
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*
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* free_all_fragments()
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* will free the address data associated with the key
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*/
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g_hash_table_foreach_remove(*fragment_table,
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free_all_fragments, NULL);
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} else {
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/* The fragment table does not exist. Create it */
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*fragment_table = g_hash_table_new_full(fragment_hash,
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fragment_equal, fragment_free_key, NULL);
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}
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}
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void
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dcerpc_fragment_table_init(GHashTable **fragment_table)
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{
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if (*fragment_table != NULL) {
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/*
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* The fragment hash table exists.
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*
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* Remove all entries and free fragment data for each entry.
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*
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* If slices are used (GLIB >= 2.10)
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* the keys are freed by calling dcerpc_fragment_free_key()
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* and the values are freed in free_all_fragments().
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*
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* free_all_fragments()
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* will free the adrress data associated with the key
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*/
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g_hash_table_foreach_remove(*fragment_table,
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free_all_fragments, NULL);
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} else {
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/* The fragment table does not exist. Create it */
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*fragment_table = g_hash_table_new_full(dcerpc_fragment_hash,
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dcerpc_fragment_equal, dcerpc_fragment_free_key, NULL);
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}
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}
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/*
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* Initialize a reassembled-packet table.
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*/
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void
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reassembled_table_init(GHashTable **reassembled_table)
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{
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if (*reassembled_table != NULL) {
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/*
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* The reassembled-packet hash table exists.
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*
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* Remove all entries and free reassembled packet
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* data for each entry.
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*/
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g_hash_table_foreach_remove(*reassembled_table,
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free_all_reassembled_fragments, NULL);
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} else {
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/* The fragment table does not exist. Create it */
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*reassembled_table = g_hash_table_new(reassembled_hash,
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reassembled_equal);
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}
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}
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/* This function cleans up the stored state and removes the reassembly data and
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* (with one exception) all allocated memory for matching reassembly.
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*
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* The exception is :
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* If the PDU was already completely reassembled, then the buffer containing the
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* reassembled data WILL NOT be free()d, and the pointer to that buffer will be
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* returned.
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* Othervise the function will return NULL.
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*
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* So, if you call fragment_delete and it returns non-NULL, YOU are responsible to
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* g_free() that buffer.
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*/
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unsigned char *
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fragment_delete(const packet_info *pinfo, const guint32 id, GHashTable *fragment_table)
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{
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fragment_data *fd_head, *fd;
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fragment_key key;
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unsigned char *data=NULL;
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/* create key to search hash with */
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key.src = pinfo->src;
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key.dst = pinfo->dst;
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key.id = id;
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fd_head = g_hash_table_lookup(fragment_table, &key);
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if(fd_head==NULL){
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/* We do not recognize this as a PDU we have seen before. return */
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return NULL;
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}
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data=fd_head->data;
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/* loop over all partial fragments and free any buffers */
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for(fd=fd_head->next;fd;){
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fragment_data *tmp_fd;
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tmp_fd=fd->next;
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if( !(fd->flags&FD_NOT_MALLOCED) )
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g_free(fd->data);
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g_slice_free(fragment_data, fd);
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fd=tmp_fd;
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}
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g_slice_free(fragment_data, fd_head);
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g_hash_table_remove(fragment_table, &key);
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return data;
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}
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/* This function is used to check if there is partial or completed reassembly state
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* matching this packet. I.e. Is there reassembly going on or not for this packet?
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*/
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fragment_data *
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fragment_get(const packet_info *pinfo, const guint32 id, GHashTable *fragment_table)
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{
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fragment_data *fd_head;
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fragment_key key;
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/* create key to search hash with */
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key.src = pinfo->src;
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key.dst = pinfo->dst;
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key.id = id;
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fd_head = g_hash_table_lookup(fragment_table, &key);
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return fd_head;
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}
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/* id *must* be the frame number for this to work! */
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fragment_data *
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fragment_get_reassembled(const guint32 id, GHashTable *reassembled_table)
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{
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fragment_data *fd_head;
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reassembled_key key;
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/* create key to search hash with */
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key.frame = id;
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key.id = id;
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fd_head = g_hash_table_lookup(reassembled_table, &key);
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return fd_head;
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}
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fragment_data *
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fragment_get_reassembled_id(const packet_info *pinfo, const guint32 id, GHashTable *reassembled_table)
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{
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fragment_data *fd_head;
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reassembled_key key;
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/* create key to search hash with */
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key.frame = pinfo->fd->num;
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key.id = id;
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fd_head = g_hash_table_lookup(reassembled_table, &key);
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return fd_head;
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}
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/* This function can be used to explicitly set the total length (if known)
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* for reassembly of a PDU.
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* This is useful for reassembly of PDUs where one may have the total length specified
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* in the first fragment instead of as for, say, IPv4 where a flag indicates which
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* is the last fragment.
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*
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* Such protocols might fragment_add with a more_frags==TRUE for every fragment
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* and just tell the reassembly engine the expected total length of the reassembled data
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* using fragment_set_tot_len immediately after doing fragment_add for the first packet.
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*
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* Note that for FD_BLOCKSEQUENCE tot_len is the index for the tail fragment.
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* i.e. since the block numbers start at 0, if we specify tot_len==2, that
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* actually means we want to defragment 3 blocks, block 0, 1 and 2.
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*/
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void
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fragment_set_tot_len(const packet_info *pinfo, const guint32 id, GHashTable *fragment_table,
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const guint32 tot_len)
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{
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fragment_data *fd_head;
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fragment_key key;
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/* create key to search hash with */
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key.src = pinfo->src;
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key.dst = pinfo->dst;
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key.id = id;
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fd_head = g_hash_table_lookup(fragment_table, &key);
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if(fd_head){
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fd_head->datalen = tot_len;
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fd_head->flags |= FD_DATALEN_SET;
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}
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return;
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}
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guint32
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fragment_get_tot_len(const packet_info *pinfo, const guint32 id, GHashTable *fragment_table)
|
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{
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fragment_data *fd_head;
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fragment_key key;
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/* create key to search hash with */
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key.src = pinfo->src;
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key.dst = pinfo->dst;
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key.id = id;
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fd_head = g_hash_table_lookup(fragment_table, &key);
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if(fd_head){
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return fd_head->datalen;
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}
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return 0;
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|
}
|
|
|
|
|
|
/* This function will set the partial reassembly flag for a fh.
|
|
When this function is called, the fh MUST already exist, i.e.
|
|
the fh MUST be created by the initial call to fragment_add() before
|
|
this function is called.
|
|
Also note that this function MUST be called to indicate a fh will be
|
|
extended (increase the already stored data)
|
|
*/
|
|
|
|
void
|
|
fragment_set_partial_reassembly(const packet_info *pinfo, const guint32 id, GHashTable *fragment_table)
|
|
{
|
|
fragment_data *fd_head;
|
|
fragment_key key;
|
|
|
|
/* create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
|
|
fd_head = g_hash_table_lookup(fragment_table, &key);
|
|
|
|
/*
|
|
* XXX - why not do all the stuff done early in "fragment_add_work()",
|
|
* turning off FD_DEFRAGMENTED and pointing the fragments' data
|
|
* pointers to the appropriate part of the already-reassembled
|
|
* data, and clearing the data length and "reassembled in" frame
|
|
* number, here? We currently have a hack in the TCP dissector
|
|
* not to set the "reassembled in" value if the "partial reassembly"
|
|
* flag is set, so that in the first pass through the packets
|
|
* we don't falsely set a packet as reassembled in that packet
|
|
* if the dissector decided that even more reassembly was needed.
|
|
*/
|
|
if(fd_head){
|
|
fd_head->flags |= FD_PARTIAL_REASSEMBLY;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This function gets rid of an entry from a fragment table, given
|
|
* a pointer to the key for that entry; it also frees up the key
|
|
* and the addresses in it.
|
|
* Note: If we use slices keys are freed by fragment_free_key()
|
|
[or dcerpc_fragment_free_key()] being called
|
|
* during g_hash_table_remove().
|
|
*/
|
|
static void
|
|
fragment_unhash(GHashTable *fragment_table, fragment_key *key)
|
|
{
|
|
/*
|
|
* Remove the entry from the fragment table.
|
|
*/
|
|
g_hash_table_remove(fragment_table, key);
|
|
|
|
/*
|
|
* Free the key itself.
|
|
*/
|
|
}
|
|
|
|
/*
|
|
* This function adds fragment_data structure to a reassembled-packet
|
|
* hash table, using the frame numbers of each of the frames from
|
|
* which it was reassembled as keys, and sets the "reassembled_in"
|
|
* frame number.
|
|
*/
|
|
static void
|
|
fragment_reassembled(fragment_data *fd_head, const packet_info *pinfo,
|
|
GHashTable *reassembled_table, const guint32 id)
|
|
{
|
|
reassembled_key *new_key;
|
|
fragment_data *fd;
|
|
|
|
if (fd_head->next == NULL) {
|
|
/*
|
|
* This was not fragmented, so there's no fragment
|
|
* table; just hash it using the current frame number.
|
|
*/
|
|
new_key = se_alloc(sizeof(reassembled_key));
|
|
new_key->frame = pinfo->fd->num;
|
|
new_key->id = id;
|
|
g_hash_table_insert(reassembled_table, new_key, fd_head);
|
|
} else {
|
|
/*
|
|
* Hash it with the frame numbers for all the frames.
|
|
*/
|
|
for (fd = fd_head->next; fd != NULL; fd = fd->next){
|
|
new_key = se_alloc(sizeof(reassembled_key));
|
|
new_key->frame = fd->frame;
|
|
new_key->id = id;
|
|
g_hash_table_insert(reassembled_table, new_key,
|
|
fd_head);
|
|
}
|
|
}
|
|
fd_head->flags |= FD_DEFRAGMENTED;
|
|
fd_head->reassembled_in = pinfo->fd->num;
|
|
}
|
|
|
|
/*
|
|
* This function adds a new fragment to the fragment hash table.
|
|
* If this is the first fragment seen for this datagram, a new entry
|
|
* is created in the hash table, otherwise this fragment is just added
|
|
* to the linked list of fragments for this packet.
|
|
* The list of fragments for a specific datagram is kept sorted for
|
|
* easier handling.
|
|
*
|
|
* Returns a pointer to the head of the fragment data list if we have all the
|
|
* fragments, NULL otherwise.
|
|
*
|
|
* This function assumes frag_offset being a byte offset into the defragment
|
|
* packet.
|
|
*
|
|
* 01-2002
|
|
* Once the fh is defragmented (= FD_DEFRAGMENTED set), it can be
|
|
* extended using the FD_PARTIAL_REASSEMBLY flag. This flag should be set
|
|
* using fragment_set_partial_reassembly() before calling fragment_add
|
|
* with the new fragment. FD_TOOLONGFRAGMENT and FD_MULTIPLETAILS flags
|
|
* are lowered when a new extension process is started.
|
|
*/
|
|
static gboolean
|
|
fragment_add_work(fragment_data *fd_head, tvbuff_t *tvb, const int offset,
|
|
const packet_info *pinfo, const guint32 frag_offset,
|
|
const guint32 frag_data_len, const gboolean more_frags)
|
|
{
|
|
fragment_data *fd;
|
|
fragment_data *fd_i;
|
|
guint32 max, dfpos;
|
|
unsigned char *old_data;
|
|
|
|
/* create new fd describing this fragment */
|
|
fd = g_slice_new(fragment_data);
|
|
fd->next = NULL;
|
|
fd->flags = 0;
|
|
fd->frame = pinfo->fd->num;
|
|
if (fd->frame > fd_head->frame)
|
|
fd_head->frame = fd->frame;
|
|
fd->offset = frag_offset;
|
|
fd->len = frag_data_len;
|
|
fd->data = NULL;
|
|
|
|
/*
|
|
* If it was already defragmented and this new fragment goes beyond
|
|
* data limits, set flag in already empty fds & point old fds to malloc'ed data.
|
|
*/
|
|
if(fd_head->flags & FD_DEFRAGMENTED && (frag_offset+frag_data_len) >= fd_head->datalen &&
|
|
fd_head->flags & FD_PARTIAL_REASSEMBLY){
|
|
for(fd_i=fd_head->next; fd_i; fd_i=fd_i->next){
|
|
if( !fd_i->data ) {
|
|
fd_i->data = fd_head->data + fd_i->offset;
|
|
fd_i->flags |= FD_NOT_MALLOCED;
|
|
}
|
|
fd_i->flags &= (~FD_TOOLONGFRAGMENT) & (~FD_MULTIPLETAILS);
|
|
}
|
|
fd_head->flags &= ~(FD_DEFRAGMENTED|FD_PARTIAL_REASSEMBLY|FD_DATALEN_SET);
|
|
fd_head->flags &= (~FD_TOOLONGFRAGMENT) & (~FD_MULTIPLETAILS);
|
|
fd_head->datalen=0;
|
|
fd_head->reassembled_in=0;
|
|
}
|
|
|
|
if (!more_frags) {
|
|
/*
|
|
* This is the tail fragment in the sequence.
|
|
*/
|
|
if (fd_head->flags & FD_DATALEN_SET) {
|
|
/* ok we have already seen other tails for this packet
|
|
* it might be a duplicate.
|
|
*/
|
|
if (fd_head->datalen != (fd->offset + fd->len) ){
|
|
/* Oops, this tail indicates a different packet
|
|
* len than the previous ones. Something's wrong.
|
|
*/
|
|
fd->flags |= FD_MULTIPLETAILS;
|
|
fd_head->flags |= FD_MULTIPLETAILS;
|
|
}
|
|
} else {
|
|
/* this was the first tail fragment, now we know the
|
|
* length of the packet
|
|
*/
|
|
fd_head->datalen = fd->offset + fd->len;
|
|
fd_head->flags |= FD_DATALEN_SET;
|
|
}
|
|
}
|
|
|
|
|
|
|
|
|
|
/* If the packet is already defragmented, this MUST be an overlap.
|
|
* The entire defragmented packet is in fd_head->data.
|
|
* Even if we have previously defragmented this packet, we still
|
|
* check it. Someone might play overlap and TTL games.
|
|
*/
|
|
if (fd_head->flags & FD_DEFRAGMENTED) {
|
|
guint32 end_offset = fd->offset + fd->len;
|
|
fd->flags |= FD_OVERLAP;
|
|
fd_head->flags |= FD_OVERLAP;
|
|
/* make sure it's not too long */
|
|
if (end_offset > fd_head->datalen || end_offset < fd->offset || end_offset < fd->len) {
|
|
fd->flags |= FD_TOOLONGFRAGMENT;
|
|
fd_head->flags |= FD_TOOLONGFRAGMENT;
|
|
}
|
|
/* make sure it doesn't conflict with previous data */
|
|
else if ( memcmp(fd_head->data+fd->offset,
|
|
tvb_get_ptr(tvb,offset,fd->len),fd->len) ){
|
|
fd->flags |= FD_OVERLAPCONFLICT;
|
|
fd_head->flags |= FD_OVERLAPCONFLICT;
|
|
}
|
|
/* it was just an overlap, link it and return */
|
|
LINK_FRAG(fd_head,fd);
|
|
return TRUE;
|
|
}
|
|
|
|
|
|
|
|
/* If we have reached this point, the packet is not defragmented yet.
|
|
* Save all payload in a buffer until we can defragment.
|
|
* XXX - what if we didn't capture the entire fragment due
|
|
* to a too-short snapshot length?
|
|
*/
|
|
fd->data = g_malloc(fd->len);
|
|
tvb_memcpy(tvb, fd->data, offset, fd->len);
|
|
LINK_FRAG(fd_head,fd);
|
|
|
|
|
|
if( !(fd_head->flags & FD_DATALEN_SET) ){
|
|
/* if we dont know the datalen, there are still missing
|
|
* packets. Cheaper than the check below.
|
|
*/
|
|
return FALSE;
|
|
}
|
|
|
|
|
|
/*
|
|
* Check if we have received the entire fragment.
|
|
* This is easy since the list is sorted and the head is faked.
|
|
*
|
|
* First, we compute the amount of contiguous data that's
|
|
* available. (The check for fd_i->offset <= max rules out
|
|
* fragments that don't start before or at the end of the
|
|
* previous fragment, i.e. fragments that have a gap between
|
|
* them and the previous fragment.)
|
|
*/
|
|
max = 0;
|
|
for (fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
|
|
if ( ((fd_i->offset)<=max) &&
|
|
((fd_i->offset+fd_i->len)>max) ){
|
|
max = fd_i->offset+fd_i->len;
|
|
}
|
|
}
|
|
|
|
if (max < (fd_head->datalen)) {
|
|
/*
|
|
* The amount of contiguous data we have is less than the
|
|
* amount of data we're trying to reassemble, so we haven't
|
|
* received all packets yet.
|
|
*/
|
|
return FALSE;
|
|
}
|
|
|
|
|
|
if (max > (fd_head->datalen)) {
|
|
/*XXX not sure if current fd was the TOOLONG*/
|
|
/*XXX is it fair to flag current fd*/
|
|
/* oops, too long fragment detected */
|
|
fd->flags |= FD_TOOLONGFRAGMENT;
|
|
fd_head->flags |= FD_TOOLONGFRAGMENT;
|
|
}
|
|
|
|
/* we have received an entire packet, defragment it and
|
|
* free all fragments
|
|
*/
|
|
/* store old data just in case */
|
|
old_data=fd_head->data;
|
|
fd_head->data = g_malloc(max);
|
|
|
|
/* add all data fragments */
|
|
for (dfpos=0,fd_i=fd_head;fd_i;fd_i=fd_i->next) {
|
|
if (fd_i->len) {
|
|
/* dfpos is always >= than fd_i->offset */
|
|
/* No gaps can exist here, max_loop(above) does this */
|
|
/* XXX - true? Can we get fd_i->offset+fd-i->len */
|
|
/* overflowing, for example? */
|
|
/* Actually: there is at least one pathological case wherein there can be fragments
|
|
* on the list which are for offsets greater than max (i.e.: following a gap after max).
|
|
* (Apparently a "DESEGMENT_UNTIL_FIN" was involved wherein the FIN packet had an offset
|
|
* less than the highest fragment offset seen. [Seen from a fuzz-test: bug #2470]).
|
|
* Note that the "overlap" compare must only be done for fragments with (offset+len) <= max
|
|
* and thus within the newly g_malloc'd buffer.
|
|
*/
|
|
|
|
if ( fd_i->offset+fd_i->len > dfpos ) {
|
|
if (fd_i->offset+fd_i->len > max)
|
|
g_warning("Reassemble error in frame %u: offset %u + len %u > max %u",
|
|
pinfo->fd->num, fd_i->offset,
|
|
fd_i->len, max);
|
|
else if (dfpos < fd_i->offset)
|
|
g_warning("Reassemble error in frame %u: dfpos %u < offset %u",
|
|
pinfo->fd->num, dfpos, fd_i->offset);
|
|
else if (dfpos-fd_i->offset > fd_i->len)
|
|
g_warning("Reassemble error in frame %u: dfpos %u - offset %u > len %u",
|
|
pinfo->fd->num, dfpos, fd_i->offset,
|
|
fd_i->len);
|
|
else if (!fd_head->data)
|
|
g_warning("Reassemble error in frame %u: no data",
|
|
pinfo->fd->num);
|
|
else {
|
|
if (fd_i->offset < dfpos) {
|
|
fd_i->flags |= FD_OVERLAP;
|
|
fd_head->flags |= FD_OVERLAP;
|
|
if ( memcmp(fd_head->data+fd_i->offset,
|
|
fd_i->data,
|
|
MIN(fd_i->len,(dfpos-fd_i->offset))
|
|
) ) {
|
|
fd_i->flags |= FD_OVERLAPCONFLICT;
|
|
fd_head->flags |= FD_OVERLAPCONFLICT;
|
|
}
|
|
}
|
|
memcpy(fd_head->data+dfpos,
|
|
fd_i->data+(dfpos-fd_i->offset),
|
|
fd_i->len-(dfpos-fd_i->offset));
|
|
}
|
|
} else {
|
|
if (fd_i->offset + fd_i->len < fd_i->offset) /* Integer overflow? */
|
|
g_warning("Reassemble error in frame %u: offset %u + len %u < offset",
|
|
pinfo->fd->num, fd_i->offset,
|
|
fd_i->len);
|
|
}
|
|
if( fd_i->flags & FD_NOT_MALLOCED )
|
|
fd_i->flags &= ~FD_NOT_MALLOCED;
|
|
else
|
|
g_free(fd_i->data);
|
|
fd_i->data=NULL;
|
|
|
|
dfpos=MAX(dfpos,(fd_i->offset+fd_i->len));
|
|
}
|
|
}
|
|
|
|
g_free(old_data);
|
|
/* mark this packet as defragmented.
|
|
allows us to skip any trailing fragments */
|
|
fd_head->flags |= FD_DEFRAGMENTED;
|
|
fd_head->reassembled_in=pinfo->fd->num;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
static fragment_data *
|
|
fragment_add_common(tvbuff_t *tvb, const int offset, const packet_info *pinfo, const guint32 id,
|
|
GHashTable *fragment_table, const guint32 frag_offset,
|
|
const guint32 frag_data_len, const gboolean more_frags,
|
|
const gboolean check_already_added)
|
|
{
|
|
fragment_key key, *new_key;
|
|
fragment_data *fd_head;
|
|
fragment_data *fd_item;
|
|
gboolean already_added=pinfo->fd->flags.visited;
|
|
|
|
|
|
/* dissector shouldn't give us garbage tvb info */
|
|
DISSECTOR_ASSERT(tvb_bytes_exist(tvb, offset, frag_data_len));
|
|
|
|
/* create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
|
|
fd_head = g_hash_table_lookup(fragment_table, &key);
|
|
|
|
#if 0
|
|
/* debug output of associated fragments. */
|
|
/* leave it here for future debugging sessions */
|
|
if(strcmp(pinfo->current_proto, "DCERPC") == 0) {
|
|
printf("proto:%s num:%u id:%u offset:%u len:%u more:%u visited:%u\n",
|
|
pinfo->current_proto, pinfo->fd->num, id, frag_offset, frag_data_len, more_frags, pinfo->fd->flags.visited);
|
|
if(fd_head != NULL) {
|
|
for(fd_item=fd_head->next;fd_item;fd_item=fd_item->next){
|
|
printf("fd_frame:%u fd_offset:%u len:%u datalen:%u\n",
|
|
fd_item->frame, fd_item->offset, fd_item->len, fd_item->datalen);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* "already_added" is true if "pinfo->fd->flags.visited" is true;
|
|
* if "pinfo->fd->flags.visited", this isn't the first pass, so
|
|
* we've already done all the reassembly and added all the
|
|
* fragments.
|
|
*
|
|
* If it's not true, but "check_already_added" is true, just check
|
|
* if we have seen this fragment before, i.e., if we have already
|
|
* added it to reassembly.
|
|
* That can be true even if "pinfo->fd->flags.visited" is false
|
|
* since we sometimes might call a subdissector multiple times.
|
|
* As an additional check, just make sure we have not already added
|
|
* this frame to the reassembly list, if there is a reassembly list;
|
|
* note that the first item in the reassembly list is not a
|
|
* fragment, it's a data structure for the reassembled packet.
|
|
* We don't check it because its "frame" member isn't initialized
|
|
* to anything, and because it doesn't count in any case.
|
|
*
|
|
* And as another additional check, make sure the fragment offsets are
|
|
* the same, as otherwise we get into trouble if multiple fragments
|
|
* are in one PDU.
|
|
*/
|
|
if (!already_added && check_already_added && fd_head != NULL) {
|
|
if (pinfo->fd->num <= fd_head->frame) {
|
|
for(fd_item=fd_head->next;fd_item;fd_item=fd_item->next){
|
|
if(pinfo->fd->num==fd_item->frame && frag_offset==fd_item->offset){
|
|
already_added=TRUE;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
/* have we already added this frame ?*/
|
|
if (already_added) {
|
|
if (fd_head != NULL && fd_head->flags & FD_DEFRAGMENTED) {
|
|
return fd_head;
|
|
} else {
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
if (fd_head==NULL){
|
|
/* not found, this must be the first snooped fragment for this
|
|
* packet. Create list-head.
|
|
*/
|
|
fd_head = new_head(0);
|
|
|
|
/*
|
|
* We're going to use the key to insert the fragment,
|
|
* so allocate a structure for it, and copy the
|
|
* addresses, allocating new buffers for the address
|
|
* data.
|
|
*/
|
|
new_key = g_slice_new(fragment_key);
|
|
COPY_ADDRESS(&new_key->src, &key.src);
|
|
COPY_ADDRESS(&new_key->dst, &key.dst);
|
|
new_key->id = key.id;
|
|
g_hash_table_insert(fragment_table, new_key, fd_head);
|
|
}
|
|
|
|
if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
|
|
frag_data_len, more_frags)) {
|
|
/*
|
|
* Reassembly is complete.
|
|
*/
|
|
return fd_head;
|
|
} else {
|
|
/*
|
|
* Reassembly isn't complete.
|
|
*/
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
fragment_data *
|
|
fragment_add(tvbuff_t *tvb, const int offset, const packet_info *pinfo, const guint32 id,
|
|
GHashTable *fragment_table, const guint32 frag_offset,
|
|
const guint32 frag_data_len, const gboolean more_frags)
|
|
{
|
|
return fragment_add_common(tvb, offset, pinfo, id, fragment_table,
|
|
frag_offset, frag_data_len, more_frags, TRUE);
|
|
}
|
|
|
|
/*
|
|
* For use when you can have multiple fragments in the same frame added
|
|
* to the same reassembled PDU, e.g. with ONC RPC-over-TCP.
|
|
*/
|
|
fragment_data *
|
|
fragment_add_multiple_ok(tvbuff_t *tvb, const int offset, const packet_info *pinfo,
|
|
const guint32 id, GHashTable *fragment_table,
|
|
const guint32 frag_offset, const guint32 frag_data_len,
|
|
const gboolean more_frags)
|
|
{
|
|
return fragment_add_common(tvb, offset, pinfo, id, fragment_table,
|
|
frag_offset, frag_data_len, more_frags, FALSE);
|
|
}
|
|
|
|
fragment_data *
|
|
fragment_add_check(tvbuff_t *tvb, const int offset, const packet_info *pinfo,
|
|
const guint32 id, GHashTable *fragment_table,
|
|
GHashTable *reassembled_table, const guint32 frag_offset,
|
|
const guint32 frag_data_len, const gboolean more_frags)
|
|
{
|
|
reassembled_key reass_key;
|
|
fragment_key key, *new_key, *old_key;
|
|
gpointer orig_key, value;
|
|
fragment_data *fd_head;
|
|
|
|
/*
|
|
* If this isn't the first pass, look for this frame in the table
|
|
* of reassembled packets.
|
|
*/
|
|
if (pinfo->fd->flags.visited) {
|
|
reass_key.frame = pinfo->fd->num;
|
|
reass_key.id = id;
|
|
return g_hash_table_lookup(reassembled_table, &reass_key);
|
|
}
|
|
|
|
/* create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
|
|
/* Looks up a key in the GHashTable, returning the original key and the associated value
|
|
* and a gboolean which is TRUE if the key was found. This is useful if you need to free
|
|
* the memory allocated for the original key, for example before calling g_hash_table_remove()
|
|
*/
|
|
if (!g_hash_table_lookup_extended(fragment_table, &key,
|
|
&orig_key, &value)) {
|
|
/* not found, this must be the first snooped fragment for this
|
|
* packet. Create list-head.
|
|
*/
|
|
fd_head = new_head(0);
|
|
|
|
/*
|
|
* We're going to use the key to insert the fragment,
|
|
* so allocate a structure for it, and copy the
|
|
* addresses, allocating new buffers for the address
|
|
* data.
|
|
*/
|
|
new_key = g_slice_new(fragment_key);
|
|
COPY_ADDRESS(&new_key->src, &key.src);
|
|
COPY_ADDRESS(&new_key->dst, &key.dst);
|
|
new_key->id = key.id;
|
|
g_hash_table_insert(fragment_table, new_key, fd_head);
|
|
|
|
orig_key = new_key; /* for unhashing it later */
|
|
} else {
|
|
/*
|
|
* We found it.
|
|
*/
|
|
fd_head = value;
|
|
}
|
|
|
|
/*
|
|
* If this is a short frame, then we can't, and don't, do
|
|
* reassembly on it. We just give up.
|
|
*/
|
|
if (tvb_reported_length(tvb) > tvb_length(tvb))
|
|
return NULL;
|
|
|
|
if (fragment_add_work(fd_head, tvb, offset, pinfo, frag_offset,
|
|
frag_data_len, more_frags)) {
|
|
/*
|
|
* Reassembly is complete.
|
|
* Remove this from the table of in-progress
|
|
* reassemblies, add it to the table of
|
|
* reassembled packets, and return it.
|
|
*/
|
|
|
|
/*
|
|
* Remove this from the table of in-progress reassemblies,
|
|
* and free up any memory used for it in that table.
|
|
*/
|
|
old_key = orig_key;
|
|
fragment_unhash(fragment_table, old_key);
|
|
|
|
/*
|
|
* Add this item to the table of reassembled packets.
|
|
*/
|
|
fragment_reassembled(fd_head, pinfo, reassembled_table, id);
|
|
return fd_head;
|
|
} else {
|
|
/*
|
|
* Reassembly isn't complete.
|
|
*/
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static void
|
|
fragment_defragment_and_free (fragment_data *fd_head, const packet_info *pinfo)
|
|
{
|
|
fragment_data *fd_i = NULL;
|
|
fragment_data *last_fd = NULL;
|
|
guint32 dfpos = 0, size = 0;
|
|
void *old_data = NULL;
|
|
|
|
for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
|
|
if(!last_fd || last_fd->offset!=fd_i->offset){
|
|
size+=fd_i->len;
|
|
}
|
|
last_fd=fd_i;
|
|
}
|
|
|
|
/* store old data in case the fd_i->data pointers refer to it */
|
|
old_data=fd_head->data;
|
|
fd_head->data = g_malloc(size);
|
|
fd_head->len = size; /* record size for caller */
|
|
|
|
/* add all data fragments */
|
|
last_fd=NULL;
|
|
for (fd_i=fd_head->next; fd_i; fd_i=fd_i->next) {
|
|
if (fd_i->len) {
|
|
if(!last_fd || last_fd->offset != fd_i->offset) {
|
|
/* First fragment or in-sequence fragment */
|
|
memcpy(fd_head->data+dfpos, fd_i->data, fd_i->len);
|
|
dfpos += fd_i->len;
|
|
} else {
|
|
/* duplicate/retransmission/overlap */
|
|
fd_i->flags |= FD_OVERLAP;
|
|
fd_head->flags |= FD_OVERLAP;
|
|
if(last_fd->len != fd_i->len
|
|
|| memcmp(last_fd->data, fd_i->data, last_fd->len) ) {
|
|
fd_i->flags |= FD_OVERLAPCONFLICT;
|
|
fd_head->flags |= FD_OVERLAPCONFLICT;
|
|
}
|
|
}
|
|
}
|
|
last_fd=fd_i;
|
|
}
|
|
|
|
/* we have defragmented the pdu, now free all fragments*/
|
|
for (fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
|
|
if( fd_i->flags & FD_NOT_MALLOCED )
|
|
fd_i->flags &= ~FD_NOT_MALLOCED;
|
|
else
|
|
g_free(fd_i->data);
|
|
fd_i->data=NULL;
|
|
}
|
|
g_free(old_data);
|
|
|
|
/* mark this packet as defragmented.
|
|
* allows us to skip any trailing fragments.
|
|
*/
|
|
fd_head->flags |= FD_DEFRAGMENTED;
|
|
fd_head->reassembled_in=pinfo->fd->num;
|
|
}
|
|
|
|
/*
|
|
* This function adds a new fragment to the entry for a reassembly
|
|
* operation.
|
|
*
|
|
* The list of fragments for a specific datagram is kept sorted for
|
|
* easier handling.
|
|
*
|
|
* Returns TRUE if we have all the fragments, FALSE otherwise.
|
|
*
|
|
* This function assumes frag_number being a block sequence number.
|
|
* The bsn for the first block is 0.
|
|
*/
|
|
static gboolean
|
|
fragment_add_seq_work(fragment_data *fd_head, tvbuff_t *tvb, const int offset,
|
|
const packet_info *pinfo, const guint32 frag_number,
|
|
const guint32 frag_data_len, const gboolean more_frags,
|
|
const guint32 flags _U_)
|
|
{
|
|
fragment_data *fd;
|
|
fragment_data *fd_i;
|
|
fragment_data *last_fd;
|
|
guint32 max, dfpos;
|
|
|
|
/* if the partial reassembly flag has been set, and we are extending
|
|
* the pdu, un-reassemble the pdu. This means pointing old fds to malloc'ed data.
|
|
*/
|
|
if(fd_head->flags & FD_DEFRAGMENTED && frag_number >= fd_head->datalen &&
|
|
fd_head->flags & FD_PARTIAL_REASSEMBLY){
|
|
guint32 lastdfpos = 0;
|
|
dfpos = 0;
|
|
for(fd_i=fd_head->next; fd_i; fd_i=fd_i->next){
|
|
if( !fd_i->data ) {
|
|
if( fd_i->flags & FD_OVERLAP ) {
|
|
/* this is a duplicate of the previous
|
|
* fragment. */
|
|
fd_i->data = fd_head->data + lastdfpos;
|
|
} else {
|
|
fd_i->data = fd_head->data + dfpos;
|
|
lastdfpos = dfpos;
|
|
dfpos += fd_i->len;
|
|
}
|
|
fd_i->flags |= FD_NOT_MALLOCED;
|
|
}
|
|
fd_i->flags &= (~FD_TOOLONGFRAGMENT) & (~FD_MULTIPLETAILS);
|
|
}
|
|
fd_head->flags &= ~(FD_DEFRAGMENTED|FD_PARTIAL_REASSEMBLY|FD_DATALEN_SET);
|
|
fd_head->flags &= (~FD_TOOLONGFRAGMENT) & (~FD_MULTIPLETAILS);
|
|
fd_head->datalen=0;
|
|
fd_head->reassembled_in=0;
|
|
}
|
|
|
|
|
|
/* create new fd describing this fragment */
|
|
fd = g_slice_new(fragment_data);
|
|
fd->next = NULL;
|
|
fd->flags = 0;
|
|
fd->frame = pinfo->fd->num;
|
|
fd->offset = frag_number;
|
|
fd->len = frag_data_len;
|
|
fd->data = NULL;
|
|
|
|
if (!more_frags) {
|
|
/*
|
|
* This is the tail fragment in the sequence.
|
|
*/
|
|
if (fd_head->flags&FD_DATALEN_SET) {
|
|
/* ok we have already seen other tails for this packet
|
|
* it might be a duplicate.
|
|
*/
|
|
if (fd_head->datalen != fd->offset ){
|
|
/* Oops, this tail indicates a different packet
|
|
* len than the previous ones. Something's wrong.
|
|
*/
|
|
fd->flags |= FD_MULTIPLETAILS;
|
|
fd_head->flags |= FD_MULTIPLETAILS;
|
|
}
|
|
} else {
|
|
/* this was the first tail fragment, now we know the
|
|
* sequence number of that fragment (which is NOT
|
|
* the length of the packet!)
|
|
*/
|
|
fd_head->datalen = fd->offset;
|
|
fd_head->flags |= FD_DATALEN_SET;
|
|
}
|
|
}
|
|
|
|
/* If the packet is already defragmented, this MUST be an overlap.
|
|
* The entire defragmented packet is in fd_head->data
|
|
* Even if we have previously defragmented this packet, we still check
|
|
* check it. Someone might play overlap and TTL games.
|
|
*/
|
|
if (fd_head->flags & FD_DEFRAGMENTED) {
|
|
fd->flags |= FD_OVERLAP;
|
|
fd_head->flags |= FD_OVERLAP;
|
|
|
|
/* make sure it's not past the end */
|
|
if (fd->offset > fd_head->datalen) {
|
|
/* new fragment comes after the end */
|
|
fd->flags |= FD_TOOLONGFRAGMENT;
|
|
fd_head->flags |= FD_TOOLONGFRAGMENT;
|
|
LINK_FRAG(fd_head,fd);
|
|
return TRUE;
|
|
}
|
|
/* make sure it doesn't conflict with previous data */
|
|
dfpos=0;
|
|
last_fd=NULL;
|
|
for (fd_i=fd_head->next;fd_i && (fd_i->offset!=fd->offset);fd_i=fd_i->next) {
|
|
if (!last_fd || last_fd->offset!=fd_i->offset){
|
|
dfpos += fd_i->len;
|
|
}
|
|
last_fd=fd_i;
|
|
}
|
|
if(fd_i){
|
|
/* new fragment overlaps existing fragment */
|
|
if(fd_i->len!=fd->len){
|
|
/*
|
|
* They have different lengths; this
|
|
* is definitely a conflict.
|
|
*/
|
|
fd->flags |= FD_OVERLAPCONFLICT;
|
|
fd_head->flags |= FD_OVERLAPCONFLICT;
|
|
LINK_FRAG(fd_head,fd);
|
|
return TRUE;
|
|
}
|
|
DISSECTOR_ASSERT(fd_head->len >= dfpos + fd->len);
|
|
if ( memcmp(fd_head->data+dfpos,
|
|
tvb_get_ptr(tvb,offset,fd->len),fd->len) ){
|
|
/*
|
|
* They have the same length, but the
|
|
* data isn't the same.
|
|
*/
|
|
fd->flags |= FD_OVERLAPCONFLICT;
|
|
fd_head->flags |= FD_OVERLAPCONFLICT;
|
|
LINK_FRAG(fd_head,fd);
|
|
return TRUE;
|
|
}
|
|
/* it was just an overlap, link it and return */
|
|
LINK_FRAG(fd_head,fd);
|
|
return TRUE;
|
|
} else {
|
|
/*
|
|
* New fragment doesn't overlap an existing
|
|
* fragment - there was presumably a gap in
|
|
* the sequence number space.
|
|
*
|
|
* XXX - what should we do here? Is it always
|
|
* the case that there are no gaps, or are there
|
|
* protcols using sequence numbers where there
|
|
* can be gaps?
|
|
*
|
|
* If the former, the check below for having
|
|
* received all the fragments should check for
|
|
* holes in the sequence number space and for the
|
|
* first sequence number being 0. If we do that,
|
|
* the only way we can get here is if this fragment
|
|
* is past the end of the sequence number space -
|
|
* but the check for "fd->offset > fd_head->datalen"
|
|
* would have caught that above, so it can't happen.
|
|
*
|
|
* If the latter, we don't have a good way of
|
|
* knowing whether reassembly is complete if we
|
|
* get packet out of order such that the "last"
|
|
* fragment doesn't show up last - but, unless
|
|
* in-order reliable delivery of fragments is
|
|
* guaranteed, an implementation of the protocol
|
|
* has no way of knowing whether reassembly is
|
|
* complete, either.
|
|
*
|
|
* For now, we just link the fragment in and
|
|
* return.
|
|
*/
|
|
LINK_FRAG(fd_head,fd);
|
|
return TRUE;
|
|
}
|
|
}
|
|
|
|
/* If we have reached this point, the packet is not defragmented yet.
|
|
* Save all payload in a buffer until we can defragment.
|
|
* XXX - what if we didn't capture the entire fragment due
|
|
* to a too-short snapshot length?
|
|
*/
|
|
/* check len, there may be a fragment with 0 len, that is actually the tail */
|
|
if (fd->len) {
|
|
fd->data = g_malloc(fd->len);
|
|
tvb_memcpy(tvb, fd->data, offset, fd->len);
|
|
}
|
|
LINK_FRAG(fd_head,fd);
|
|
|
|
|
|
if( !(fd_head->flags & FD_DATALEN_SET) ){
|
|
/* if we dont know the sequence number of the last fragment,
|
|
* there are definitely still missing packets. Cheaper than
|
|
* the check below.
|
|
*/
|
|
return FALSE;
|
|
}
|
|
|
|
|
|
/* check if we have received the entire fragment
|
|
* this is easy since the list is sorted and the head is faked.
|
|
* common case the whole list is scanned.
|
|
*/
|
|
max = 0;
|
|
for(fd_i=fd_head->next;fd_i;fd_i=fd_i->next) {
|
|
if ( fd_i->offset==max ){
|
|
max++;
|
|
}
|
|
}
|
|
/* max will now be datalen+1 if all fragments have been seen */
|
|
|
|
if (max <= fd_head->datalen) {
|
|
/* we have not received all packets yet */
|
|
return FALSE;
|
|
}
|
|
|
|
|
|
if (max > (fd_head->datalen+1)) {
|
|
/* oops, too long fragment detected */
|
|
fd->flags |= FD_TOOLONGFRAGMENT;
|
|
fd_head->flags |= FD_TOOLONGFRAGMENT;
|
|
}
|
|
|
|
|
|
/* we have received an entire packet, defragment it and
|
|
* free all fragments
|
|
*/
|
|
fragment_defragment_and_free(fd_head, pinfo);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
* This function adds a new fragment to the fragment hash table.
|
|
* If this is the first fragment seen for this datagram, a new entry
|
|
* is created in the hash table, otherwise this fragment is just added
|
|
* to the linked list of fragments for this packet.
|
|
*
|
|
* Returns a pointer to the head of the fragment data list if we have all the
|
|
* fragments, NULL otherwise.
|
|
*
|
|
* This function assumes frag_number being a block sequence number.
|
|
* The bsn for the first block is 0.
|
|
*/
|
|
fragment_data *
|
|
fragment_add_seq(tvbuff_t *tvb, const int offset, const packet_info *pinfo, const guint32 id,
|
|
GHashTable *fragment_table, const guint32 frag_number,
|
|
const guint32 frag_data_len, const gboolean more_frags)
|
|
{
|
|
fragment_key key;
|
|
|
|
/* create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
|
|
return fragment_add_seq_key(tvb, offset, pinfo,
|
|
&key, fragment_key_copy,
|
|
fragment_table, frag_number,
|
|
frag_data_len, more_frags, 0);
|
|
}
|
|
|
|
|
|
fragment_data *
|
|
fragment_add_dcerpc_dg(tvbuff_t *tvb, const int offset, const packet_info *pinfo, const guint32 id,
|
|
void *v_act_id,
|
|
GHashTable *fragment_table, const guint32 frag_number,
|
|
const guint32 frag_data_len, const gboolean more_frags)
|
|
{
|
|
e_uuid_t *act_id = (e_uuid_t *)v_act_id;
|
|
dcerpc_fragment_key key;
|
|
|
|
/* create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
key.act_id = *act_id;
|
|
|
|
return fragment_add_seq_key(tvb, offset, pinfo,
|
|
&key, dcerpc_fragment_key_copy,
|
|
fragment_table, frag_number,
|
|
frag_data_len, more_frags, 0);
|
|
}
|
|
|
|
fragment_data *
|
|
fragment_add_seq_key(tvbuff_t *tvb, const int offset, const packet_info *pinfo,
|
|
void *key, fragment_key_copier key_copier,
|
|
GHashTable *fragment_table, guint32 frag_number,
|
|
const guint32 frag_data_len, const gboolean more_frags,
|
|
const guint32 flags)
|
|
{
|
|
fragment_data *fd_head;
|
|
fd_head = g_hash_table_lookup(fragment_table, key);
|
|
|
|
/* have we already seen this frame ?*/
|
|
if (pinfo->fd->flags.visited) {
|
|
if (fd_head != NULL && fd_head->flags & FD_DEFRAGMENTED) {
|
|
return fd_head;
|
|
} else {
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
if (fd_head==NULL){
|
|
/* not found, this must be the first snooped fragment for this
|
|
* packet. Create list-head.
|
|
*/
|
|
fd_head= new_head(FD_BLOCKSEQUENCE);
|
|
|
|
if((flags & (REASSEMBLE_FLAGS_NO_FRAG_NUMBER|REASSEMBLE_FLAGS_802_11_HACK))
|
|
&& !more_frags) {
|
|
/*
|
|
* This is the last fragment for this packet, and
|
|
* is the only one we've seen.
|
|
*
|
|
* Either we don't have sequence numbers, in which
|
|
* case we assume this is the first fragment for
|
|
* this packet, or we're doing special 802.11
|
|
* processing, in which case we assume it's one
|
|
* of those reassembled packets with a non-zero
|
|
* fragment number (see packet-80211.c); just
|
|
* return a pointer to the head of the list;
|
|
* fragment_add_seq_check will then add it to the table
|
|
* of reassembled packets.
|
|
*/
|
|
fd_head->reassembled_in=pinfo->fd->num;
|
|
return fd_head;
|
|
}
|
|
|
|
/*
|
|
* We're going to use the key to insert the fragment,
|
|
* so copy it to a long-term store.
|
|
*/
|
|
if(key_copier != NULL)
|
|
key = key_copier(key);
|
|
g_hash_table_insert(fragment_table, key, fd_head);
|
|
|
|
/*
|
|
* If we weren't given an initial fragment number,
|
|
* make it 0.
|
|
*/
|
|
if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER)
|
|
frag_number = 0;
|
|
} else {
|
|
if (flags & REASSEMBLE_FLAGS_NO_FRAG_NUMBER) {
|
|
fragment_data *fd;
|
|
/*
|
|
* If we weren't given an initial fragment number,
|
|
* use the next expected fragment number as the fragment
|
|
* number for this fragment.
|
|
*/
|
|
for (fd = fd_head; fd != NULL; fd = fd->next) {
|
|
if (fd->next == NULL)
|
|
frag_number = fd->offset + 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* XXX I've copied this over from the old separate
|
|
* fragment_add_seq_check_work, but I'm not convinced it's doing the
|
|
* right thing -- rav
|
|
*
|
|
* If we don't have all the data that is in this fragment,
|
|
* then we can't, and don't, do reassembly on it.
|
|
*
|
|
* If it's the first frame, handle it as an unfragmented packet.
|
|
* Otherwise, just handle it as a fragment.
|
|
*
|
|
* If "more_frags" isn't set, we get rid of the entry in the
|
|
* hash table for this reassembly, as we don't need it any more.
|
|
*/
|
|
if ((flags & REASSEMBLE_FLAGS_CHECK_DATA_PRESENT) &&
|
|
!tvb_bytes_exist(tvb, offset, frag_data_len)) {
|
|
if (!more_frags) {
|
|
gpointer orig_key;
|
|
/*
|
|
* Remove this from the table of in-progress
|
|
* reassemblies, and free up any memory used for
|
|
* it in that table.
|
|
*/
|
|
if (g_hash_table_lookup_extended(fragment_table, key,
|
|
&orig_key, NULL)) {
|
|
fragment_unhash(fragment_table, (fragment_key *)orig_key);
|
|
}
|
|
}
|
|
fd_head -> flags |= FD_DATA_NOT_PRESENT;
|
|
return frag_number == 0 ? fd_head : NULL;
|
|
}
|
|
|
|
if (fragment_add_seq_work(fd_head, tvb, offset, pinfo,
|
|
frag_number, frag_data_len, more_frags, flags)) {
|
|
/*
|
|
* Reassembly is complete.
|
|
*/
|
|
return fd_head;
|
|
} else {
|
|
/*
|
|
* Reassembly isn't complete.
|
|
*/
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This does the work for "fragment_add_seq_check()" and
|
|
* "fragment_add_seq_next()".
|
|
*
|
|
* This function assumes frag_number being a block sequence number.
|
|
* The bsn for the first block is 0.
|
|
*
|
|
* If "no_frag_number" is TRUE, it uses the next expected fragment number
|
|
* as the fragment number if there is a reassembly in progress, otherwise
|
|
* it uses 0.
|
|
*
|
|
* If "no_frag_number" is FALSE, it uses the "frag_number" argument as
|
|
* the fragment number.
|
|
*
|
|
* If this is the first fragment seen for this datagram, a new
|
|
* "fragment_data" structure is allocated to refer to the reassembled
|
|
* packet.
|
|
*
|
|
* This fragment is added to the linked list of fragments for this packet.
|
|
*
|
|
* If "more_frags" is false and REASSEMBLE_FLAGS_802_11_HACK (as the name
|
|
* implies, a special hack for 802.11) or REASSEMBLE_FLAGS_NO_FRAG_NUMBER
|
|
* (implying messages must be in order since there's no sequence number) are
|
|
* set in "flags", then this (one element) list is returned.
|
|
*
|
|
* If, after processing this fragment, we have all the fragments,
|
|
* "fragment_add_seq_check_work()" removes that from the fragment hash
|
|
* table if necessary and adds it to the table of reassembled fragments,
|
|
* and returns a pointer to the head of the fragment list.
|
|
*
|
|
* Otherwise, it returns NULL.
|
|
*
|
|
* XXX - Should we simply return NULL for zero-length fragments?
|
|
*/
|
|
static fragment_data *
|
|
fragment_add_seq_check_work(tvbuff_t *tvb, const int offset,
|
|
const packet_info *pinfo, const guint32 id,
|
|
GHashTable *fragment_table,
|
|
GHashTable *reassembled_table,
|
|
const guint32 frag_number,
|
|
const guint32 frag_data_len,
|
|
const gboolean more_frags, const guint32 flags)
|
|
{
|
|
reassembled_key reass_key;
|
|
fragment_key key;
|
|
fragment_data *fd_head;
|
|
|
|
/*
|
|
* Have we already seen this frame?
|
|
* If so, look for it in the table of reassembled packets.
|
|
*/
|
|
if (pinfo->fd->flags.visited) {
|
|
reass_key.frame = pinfo->fd->num;
|
|
reass_key.id = id;
|
|
return g_hash_table_lookup(reassembled_table, &reass_key);
|
|
}
|
|
|
|
/* create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
|
|
fd_head = fragment_add_seq_key(tvb, offset, pinfo,
|
|
&key, fragment_key_copy,
|
|
fragment_table, frag_number,
|
|
frag_data_len, more_frags, flags|REASSEMBLE_FLAGS_CHECK_DATA_PRESENT);
|
|
if (fd_head) {
|
|
gpointer orig_key;
|
|
|
|
if(fd_head->flags & FD_DATA_NOT_PRESENT) {
|
|
/* this is the first fragment of a datagram with
|
|
* truncated fragments. Don't move it to the
|
|
* reassembled table. */
|
|
return fd_head;
|
|
}
|
|
|
|
/*
|
|
* Reassembly is complete.
|
|
* Remove this from the table of in-progress
|
|
* reassemblies, add it to the table of
|
|
* reassembled packets, and return it.
|
|
*/
|
|
if (g_hash_table_lookup_extended(fragment_table, &key,
|
|
&orig_key, NULL)) {
|
|
/*
|
|
* Remove this from the table of in-progress reassemblies,
|
|
* and free up any memory used for it in that table.
|
|
*/
|
|
fragment_unhash(fragment_table, (fragment_key *)orig_key);
|
|
}
|
|
|
|
/*
|
|
* Add this item to the table of reassembled packets.
|
|
*/
|
|
fragment_reassembled(fd_head, pinfo, reassembled_table, id);
|
|
return fd_head;
|
|
} else {
|
|
/*
|
|
* Reassembly isn't complete.
|
|
*/
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
fragment_data *
|
|
fragment_add_seq_check(tvbuff_t *tvb, const int offset,
|
|
const packet_info *pinfo, const guint32 id,
|
|
GHashTable *fragment_table,
|
|
GHashTable *reassembled_table, const guint32 frag_number,
|
|
const guint32 frag_data_len, const gboolean more_frags)
|
|
{
|
|
return fragment_add_seq_check_work(tvb, offset, pinfo, id,
|
|
fragment_table, reassembled_table,
|
|
frag_number, frag_data_len,
|
|
more_frags, 0);
|
|
}
|
|
|
|
fragment_data *
|
|
fragment_add_seq_802_11(tvbuff_t *tvb, const int offset,
|
|
const packet_info *pinfo, const guint32 id,
|
|
GHashTable *fragment_table,
|
|
GHashTable *reassembled_table,
|
|
const guint32 frag_number, const guint32 frag_data_len,
|
|
const gboolean more_frags)
|
|
{
|
|
return fragment_add_seq_check_work(tvb, offset, pinfo, id,
|
|
fragment_table, reassembled_table,
|
|
frag_number, frag_data_len,
|
|
more_frags,
|
|
REASSEMBLE_FLAGS_802_11_HACK);
|
|
}
|
|
|
|
fragment_data *
|
|
fragment_add_seq_next(tvbuff_t *tvb, const int offset, const packet_info *pinfo,
|
|
const guint32 id, GHashTable *fragment_table,
|
|
GHashTable *reassembled_table, const guint32 frag_data_len,
|
|
const gboolean more_frags)
|
|
{
|
|
return fragment_add_seq_check_work(tvb, offset, pinfo, id,
|
|
fragment_table, reassembled_table, 0,
|
|
frag_data_len, more_frags,
|
|
REASSEMBLE_FLAGS_NO_FRAG_NUMBER);
|
|
}
|
|
|
|
void
|
|
fragment_start_seq_check(const packet_info *pinfo, const guint32 id, GHashTable *fragment_table,
|
|
const guint32 tot_len)
|
|
{
|
|
fragment_key key, *new_key;
|
|
fragment_data *fd_head;
|
|
|
|
/* Have we already seen this frame ?*/
|
|
if (pinfo->fd->flags.visited) {
|
|
return;
|
|
}
|
|
|
|
/* Create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
|
|
/* Check if fragment data exist for this key */
|
|
fd_head = g_hash_table_lookup(fragment_table, &key);
|
|
|
|
if (fd_head == NULL) {
|
|
/* Create list-head. */
|
|
fd_head = g_slice_new(fragment_data);
|
|
fd_head->next = NULL;
|
|
fd_head->datalen = tot_len;
|
|
fd_head->offset = 0;
|
|
fd_head->len = 0;
|
|
fd_head->flags = FD_BLOCKSEQUENCE|FD_DATALEN_SET;
|
|
fd_head->data = NULL;
|
|
fd_head->reassembled_in = 0;
|
|
/*
|
|
* We're going to use the key to insert the fragment,
|
|
* so copy it to a long-term store.
|
|
*/
|
|
new_key = fragment_key_copy(&key);
|
|
g_hash_table_insert(fragment_table, new_key, fd_head);
|
|
}
|
|
}
|
|
|
|
fragment_data *
|
|
fragment_end_seq_next(const packet_info *pinfo, const guint32 id, GHashTable *fragment_table,
|
|
GHashTable *reassembled_table)
|
|
{
|
|
reassembled_key reass_key;
|
|
reassembled_key *new_key;
|
|
fragment_key key;
|
|
fragment_data *fd_head;
|
|
|
|
/*
|
|
* Have we already seen this frame?
|
|
* If so, look for it in the table of reassembled packets.
|
|
*/
|
|
if (pinfo->fd->flags.visited) {
|
|
reass_key.frame = pinfo->fd->num;
|
|
reass_key.id = id;
|
|
return g_hash_table_lookup(reassembled_table, &reass_key);
|
|
}
|
|
|
|
/* create key to search hash with */
|
|
key.src = pinfo->src;
|
|
key.dst = pinfo->dst;
|
|
key.id = id;
|
|
|
|
fd_head = g_hash_table_lookup (fragment_table, &key);
|
|
|
|
if (fd_head) {
|
|
gpointer orig_key;
|
|
|
|
if (fd_head->flags & FD_DATA_NOT_PRESENT) {
|
|
/* No data added */
|
|
return NULL;
|
|
}
|
|
|
|
fd_head->datalen = fd_head->offset;
|
|
fd_head->flags |= FD_DATALEN_SET;
|
|
|
|
fragment_defragment_and_free (fd_head, pinfo);
|
|
|
|
/*
|
|
* Remove this from the table of in-progress
|
|
* reassemblies, add it to the table of
|
|
* reassembled packets, and return it.
|
|
*/
|
|
if (g_hash_table_lookup_extended(fragment_table, &key,
|
|
&orig_key, NULL)) {
|
|
/*
|
|
* Remove this from the table of in-progress reassemblies,
|
|
* and free up any memory used for it in that table.
|
|
*/
|
|
fragment_unhash(fragment_table, (fragment_key *)orig_key);
|
|
}
|
|
|
|
/*
|
|
* Add this item to the table of reassembled packets.
|
|
*/
|
|
fragment_reassembled(fd_head, pinfo, reassembled_table, id);
|
|
if (fd_head->next != NULL) {
|
|
new_key = se_alloc(sizeof(reassembled_key));
|
|
new_key->frame = pinfo->fd->num;
|
|
new_key->id = id;
|
|
g_hash_table_insert(reassembled_table, new_key, fd_head);
|
|
}
|
|
|
|
return fd_head;
|
|
} else {
|
|
/*
|
|
* Fragment data not found.
|
|
*/
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Process reassembled data; if we're on the frame in which the data
|
|
* was reassembled, put the fragment information into the protocol
|
|
* tree, and construct a tvbuff with the reassembled data, otherwise
|
|
* just put a "reassembled in" item into the protocol tree.
|
|
*/
|
|
tvbuff_t *
|
|
process_reassembled_data(tvbuff_t *tvb, const int offset, packet_info *pinfo,
|
|
const char *name, fragment_data *fd_head, const fragment_items *fit,
|
|
gboolean *update_col_infop, proto_tree *tree)
|
|
{
|
|
tvbuff_t *next_tvb;
|
|
gboolean update_col_info;
|
|
proto_item *frag_tree_item;
|
|
|
|
if (fd_head != NULL && pinfo->fd->num == fd_head->reassembled_in) {
|
|
/*
|
|
* OK, we've reassembled this.
|
|
* Is this something that's been reassembled from more
|
|
* than one fragment?
|
|
*/
|
|
if (fd_head->next != NULL) {
|
|
/*
|
|
* Yes.
|
|
* Allocate a new tvbuff, referring to the
|
|
* reassembled payload.
|
|
*/
|
|
if (fd_head->flags & FD_BLOCKSEQUENCE) {
|
|
next_tvb = tvb_new_real_data(fd_head->data,
|
|
fd_head->len, fd_head->len);
|
|
} else {
|
|
next_tvb = tvb_new_real_data(fd_head->data,
|
|
fd_head->datalen, fd_head->datalen);
|
|
}
|
|
|
|
/*
|
|
* Add the tvbuff to the list of tvbuffs to which
|
|
* the tvbuff we were handed refers, so it'll get
|
|
* cleaned up when that tvbuff is cleaned up.
|
|
*/
|
|
tvb_set_child_real_data_tvbuff(tvb, next_tvb);
|
|
|
|
/* Add the defragmented data to the data source list. */
|
|
add_new_data_source(pinfo, next_tvb, name);
|
|
|
|
/* show all fragments */
|
|
if (fd_head->flags & FD_BLOCKSEQUENCE) {
|
|
update_col_info = !show_fragment_seq_tree(
|
|
fd_head, fit, tree, pinfo, next_tvb, &frag_tree_item);
|
|
} else {
|
|
update_col_info = !show_fragment_tree(fd_head,
|
|
fit, tree, pinfo, next_tvb, &frag_tree_item);
|
|
}
|
|
} else {
|
|
/*
|
|
* No.
|
|
* Return a tvbuff with the payload.
|
|
*/
|
|
next_tvb = tvb_new_subset_remaining(tvb, offset);
|
|
pinfo->fragmented = FALSE; /* one-fragment packet */
|
|
update_col_info = TRUE;
|
|
}
|
|
if (update_col_infop != NULL)
|
|
*update_col_infop = update_col_info;
|
|
} else {
|
|
/*
|
|
* We don't have the complete reassembled payload, or this
|
|
* isn't the final frame of that payload.
|
|
*/
|
|
next_tvb = NULL;
|
|
|
|
/*
|
|
* If we know what frame this was reassembled in,
|
|
* and if there's a field to use for the number of
|
|
* the frame in which the packet was reassembled,
|
|
* add it to the protocol tree.
|
|
*/
|
|
if (fd_head != NULL && fit->hf_reassembled_in != NULL) {
|
|
proto_tree_add_uint(tree,
|
|
*(fit->hf_reassembled_in), tvb,
|
|
0, 0, fd_head->reassembled_in);
|
|
}
|
|
}
|
|
return next_tvb;
|
|
}
|
|
|
|
/*
|
|
* Show a single fragment in a fragment subtree, and put information about
|
|
* it in the top-level item for that subtree.
|
|
*/
|
|
static void
|
|
show_fragment(fragment_data *fd, const int offset, const fragment_items *fit,
|
|
proto_tree *ft, proto_item *fi, const gboolean first_frag,
|
|
const guint32 count, tvbuff_t *tvb, packet_info *pinfo)
|
|
{
|
|
proto_item *fei=NULL;
|
|
int hf;
|
|
|
|
if (first_frag) {
|
|
gchar *name;
|
|
if (count == 1) {
|
|
name = g_strdup(proto_registrar_get_name(*(fit->hf_fragment)));
|
|
} else {
|
|
name = g_strdup(proto_registrar_get_name(*(fit->hf_fragments)));
|
|
}
|
|
proto_item_set_text(fi, "%u %s (%u byte%s): ", count, name, tvb_length(tvb),
|
|
plurality(tvb_length(tvb), "", "s"));
|
|
g_free(name);
|
|
} else {
|
|
proto_item_append_text(fi, ", ");
|
|
}
|
|
proto_item_append_text(fi, "#%u(%u)", fd->frame, fd->len);
|
|
|
|
if (fd->flags & (FD_OVERLAPCONFLICT
|
|
|FD_MULTIPLETAILS|FD_TOOLONGFRAGMENT) ) {
|
|
hf = *(fit->hf_fragment_error);
|
|
} else {
|
|
hf = *(fit->hf_fragment);
|
|
}
|
|
if (fd->len == 0) {
|
|
fei = proto_tree_add_uint_format(ft, hf,
|
|
tvb, offset, fd->len,
|
|
fd->frame,
|
|
"Frame: %u (no data)",
|
|
fd->frame);
|
|
} else {
|
|
fei = proto_tree_add_uint_format(ft, hf,
|
|
tvb, offset, fd->len,
|
|
fd->frame,
|
|
"Frame: %u, payload: %u-%u (%u byte%s)",
|
|
fd->frame,
|
|
offset,
|
|
offset+fd->len-1,
|
|
fd->len,
|
|
plurality(fd->len, "", "s"));
|
|
}
|
|
PROTO_ITEM_SET_GENERATED(fei);
|
|
mark_frame_as_depended_upon(pinfo, fd->frame);
|
|
if (fd->flags & (FD_OVERLAP|FD_OVERLAPCONFLICT
|
|
|FD_MULTIPLETAILS|FD_TOOLONGFRAGMENT) ) {
|
|
/* this fragment has some flags set, create a subtree
|
|
* for it and display the flags.
|
|
*/
|
|
proto_tree *fet=NULL;
|
|
|
|
fet = proto_item_add_subtree(fei, *(fit->ett_fragment));
|
|
if (fd->flags&FD_OVERLAP) {
|
|
fei=proto_tree_add_boolean(fet,
|
|
*(fit->hf_fragment_overlap),
|
|
tvb, 0, 0,
|
|
TRUE);
|
|
PROTO_ITEM_SET_GENERATED(fei);
|
|
}
|
|
if (fd->flags&FD_OVERLAPCONFLICT) {
|
|
fei=proto_tree_add_boolean(fet,
|
|
*(fit->hf_fragment_overlap_conflict),
|
|
tvb, 0, 0,
|
|
TRUE);
|
|
PROTO_ITEM_SET_GENERATED(fei);
|
|
}
|
|
if (fd->flags&FD_MULTIPLETAILS) {
|
|
fei=proto_tree_add_boolean(fet,
|
|
*(fit->hf_fragment_multiple_tails),
|
|
tvb, 0, 0,
|
|
TRUE);
|
|
PROTO_ITEM_SET_GENERATED(fei);
|
|
}
|
|
if (fd->flags&FD_TOOLONGFRAGMENT) {
|
|
fei=proto_tree_add_boolean(fet,
|
|
*(fit->hf_fragment_too_long_fragment),
|
|
tvb, 0, 0,
|
|
TRUE);
|
|
PROTO_ITEM_SET_GENERATED(fei);
|
|
}
|
|
}
|
|
}
|
|
|
|
static gboolean
|
|
show_fragment_errs_in_col(fragment_data *fd_head, const fragment_items *fit,
|
|
packet_info *pinfo)
|
|
{
|
|
if (fd_head->flags & (FD_OVERLAPCONFLICT
|
|
|FD_MULTIPLETAILS|FD_TOOLONGFRAGMENT) ) {
|
|
if (check_col(pinfo->cinfo, COL_INFO)) {
|
|
col_add_fstr(pinfo->cinfo, COL_INFO,
|
|
"[Illegal %s]", fit->tag);
|
|
return TRUE;
|
|
}
|
|
}
|
|
|
|
return FALSE;
|
|
}
|
|
|
|
/* This function will build the fragment subtree; it's for fragments
|
|
reassembled with "fragment_add()".
|
|
|
|
It will return TRUE if there were fragmentation errors
|
|
or FALSE if fragmentation was ok.
|
|
*/
|
|
gboolean
|
|
show_fragment_tree(fragment_data *fd_head, const fragment_items *fit,
|
|
proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
|
|
{
|
|
fragment_data *fd;
|
|
proto_tree *ft;
|
|
gboolean first_frag;
|
|
guint32 count = 0;
|
|
/* It's not fragmented. */
|
|
pinfo->fragmented = FALSE;
|
|
|
|
*fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA);
|
|
PROTO_ITEM_SET_GENERATED(*fi);
|
|
|
|
ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
|
|
first_frag = TRUE;
|
|
for (fd = fd_head->next; fd != NULL; fd = fd->next) {
|
|
count++;
|
|
}
|
|
for (fd = fd_head->next; fd != NULL; fd = fd->next) {
|
|
show_fragment(fd, fd->offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
|
|
first_frag = FALSE;
|
|
}
|
|
|
|
if (fit->hf_fragment_count) {
|
|
proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
|
|
tvb, 0, 0, count);
|
|
PROTO_ITEM_SET_GENERATED(fli);
|
|
}
|
|
|
|
if (fit->hf_reassembled_length) {
|
|
proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
|
|
tvb, 0, 0, tvb_length (tvb));
|
|
PROTO_ITEM_SET_GENERATED(fli);
|
|
}
|
|
|
|
return show_fragment_errs_in_col(fd_head, fit, pinfo);
|
|
}
|
|
|
|
/* This function will build the fragment subtree; it's for fragments
|
|
reassembled with "fragment_add_seq()" or "fragment_add_seq_check()".
|
|
|
|
It will return TRUE if there were fragmentation errors
|
|
or FALSE if fragmentation was ok.
|
|
*/
|
|
gboolean
|
|
show_fragment_seq_tree(fragment_data *fd_head, const fragment_items *fit,
|
|
proto_tree *tree, packet_info *pinfo, tvbuff_t *tvb, proto_item **fi)
|
|
{
|
|
guint32 offset, next_offset, count = 0;
|
|
fragment_data *fd, *last_fd;
|
|
proto_tree *ft;
|
|
gboolean first_frag;
|
|
|
|
/* It's not fragmented. */
|
|
pinfo->fragmented = FALSE;
|
|
|
|
*fi = proto_tree_add_item(tree, *(fit->hf_fragments), tvb, 0, -1, ENC_NA);
|
|
PROTO_ITEM_SET_GENERATED(*fi);
|
|
|
|
ft = proto_item_add_subtree(*fi, *(fit->ett_fragments));
|
|
offset = 0;
|
|
next_offset = 0;
|
|
last_fd = NULL;
|
|
first_frag = TRUE;
|
|
for (fd = fd_head->next; fd != NULL; fd = fd->next){
|
|
count++;
|
|
}
|
|
for (fd = fd_head->next; fd != NULL; fd = fd->next){
|
|
if (last_fd == NULL || last_fd->offset != fd->offset) {
|
|
offset = next_offset;
|
|
next_offset += fd->len;
|
|
}
|
|
last_fd = fd;
|
|
show_fragment(fd, offset, fit, ft, *fi, first_frag, count, tvb, pinfo);
|
|
first_frag = FALSE;
|
|
}
|
|
|
|
if (fit->hf_fragment_count) {
|
|
proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_fragment_count),
|
|
tvb, 0, 0, count);
|
|
PROTO_ITEM_SET_GENERATED(fli);
|
|
}
|
|
|
|
if (fit->hf_reassembled_length) {
|
|
proto_item *fli = proto_tree_add_uint(ft, *(fit->hf_reassembled_length),
|
|
tvb, 0, 0, tvb_length (tvb));
|
|
PROTO_ITEM_SET_GENERATED(fli);
|
|
}
|
|
|
|
return show_fragment_errs_in_col(fd_head, fit, pinfo);
|
|
}
|
|
|
|
/*
|
|
* Local Variables:
|
|
* c-basic-offset: 8
|
|
* indent-tabs-mode: t
|
|
* tab-width: 8
|
|
* End:
|
|
*/
|