Move the following files from /trunk to /trunk/epan:

asn1.[ch]
follow.[ch]
ptvcursor.[ch]
reassemble.[ch]
xmlstub.[ch]

fix #include statements accordingly.

svn path=/trunk/; revision=13366

1 files changed, 1833 insertions, 0 deletions

diff --git a/epan/reassemble.c b/epan/reassemble.c
new file mode 100644
index 0000000000..9622d390e2
--- /dev/null
+++ b/epan/reassemble.c
@@ -0,0 +1,1833 @@
+/* reassemble.c
+ * Routines for {fragment,segment} reassembly
+ *
+ * $Id$
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@ethereal.com>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <string.h>
+
+#include <epan/packet.h>
+
+#include <epan/reassemble.h>
+
+#include <epan/dissectors/packet-dcerpc.h>
+
+typedef struct _fragment_key {
+	address src;
+	address dst;
+	guint32	id;
+} fragment_key;
+
+typedef struct _dcerpc_fragment_key {
+       address src;
+       address dst;
+       guint32 id;
+    e_uuid_t act_id;
+} dcerpc_fragment_key;
+
+static GMemChunk *fragment_key_chunk = NULL;
+static GMemChunk *dcerpc_fragment_key_chunk = NULL;
+static GMemChunk *fragment_data_chunk = NULL;
+static int fragment_init_count = 200;
+
+#define LINK_FRAG(fd_head,fd)					\
+	{ 	fragment_data *fd_i;				\
+		/* add fragment to list, keep list sorted */		\
+		for(fd_i=(fd_head);fd_i->next;fd_i=fd_i->next){	\
+			if( ((fd)->offset) < (fd_i->next->offset) )	\
+				break;					\
+		}							\
+		(fd)->next=fd_i->next;				\
+		fd_i->next=(fd);					\
+	}
+
+static gint
+fragment_equal(gconstpointer k1, gconstpointer k2)
+{
+	const fragment_key* key1 = (const fragment_key*) k1;
+	const fragment_key* key2 = (const fragment_key*) k2;
+
+	/*key.id is the first item to compare since item is most
+	  likely to differ between sessions, thus shortcircuiting
+	  the comparasion of addresses.
+	*/
+	return ( ( (key1->id    == key2->id) &&
+		   (ADDRESSES_EQUAL(&key1->src, &key2->src)) &&
+		   (ADDRESSES_EQUAL(&key1->dst, &key2->dst))
+		 ) ?
+		 TRUE : FALSE);
+}
+
+static guint
+fragment_hash(gconstpointer k)
+{
+	const fragment_key* key = (const fragment_key*) k;
+	guint hash_val;
+/*
+	int i;
+*/
+
+	hash_val = 0;
+
+/* 	More than likely: in most captures src and dst addresses are the
+	same, and would hash the same.
+	We only use id as the hash as an optimization.
+
+	for (i = 0; i < key->src.len; i++)
+		hash_val += key->src.data[i];
+	for (i = 0; i < key->dst.len; i++)
+		hash_val += key->dst.data[i];
+*/
+
+	hash_val += key->id;
+
+	return hash_val;
+}
+
+static gint
+dcerpc_fragment_equal(gconstpointer k1, gconstpointer k2)
+{
+       const dcerpc_fragment_key* key1 = (const dcerpc_fragment_key*) k1;
+       const dcerpc_fragment_key* key2 = (const dcerpc_fragment_key*) k2;
+
+       /*key.id is the first item to compare since item is most
+         likely to differ between sessions, thus shortcircuiting
+         the comparasion of addresses.
+       */
+       return (((key1->id == key2->id)
+             && (ADDRESSES_EQUAL(&key1->src, &key2->src))
+             && (ADDRESSES_EQUAL(&key1->dst, &key2->dst))
+             && (memcmp (&key1->act_id, &key2->act_id, sizeof (e_uuid_t)) == 0))
+            ? TRUE : FALSE);
+}
+
+static guint
+dcerpc_fragment_hash(gconstpointer k)
+{
+       const dcerpc_fragment_key* key = (const dcerpc_fragment_key*) k;
+       guint hash_val;
+
+       hash_val = 0;
+
+       hash_val += key->id;
+       hash_val += key->act_id.Data1;
+       hash_val += key->act_id.Data2 << 16;
+       hash_val += key->act_id.Data3;
+
+       return hash_val;
+}
+
+typedef struct _reassembled_key {
+	guint32	id;
+	guint32 frame;
+} reassembled_key;
+
+static GMemChunk *reassembled_key_chunk = NULL;
+
+static gint
+reassembled_equal(gconstpointer k1, gconstpointer k2)
+{
+	const reassembled_key* key1 = (const reassembled_key*) k1;
+	const reassembled_key* key2 = (const reassembled_key*) k2;
+
+	/*
+	 * We assume that the frame numbers are unlikely to be equal,
+	 * so we check them first.
+	 */
+	return key1->frame == key2->frame && key1->id == key2->id;
+}
+
+static guint
+reassembled_hash(gconstpointer k)
+{
+	const reassembled_key* key = (const reassembled_key*) k;
+
+	return key->frame;
+}
+
+/*
+ * For a fragment hash table entry, free the address data to which the key
+ * refers and the fragment data to which the value refers.
+ * (The actual key and value structures get freed by "reassemble_init()".)
+ */
+static gboolean
+free_all_fragments(gpointer key_arg, gpointer value, gpointer user_data _U_)
+{
+	fragment_key *key = key_arg;
+	fragment_data *fd_head;
+
+	/*
+	 * Grr.  I guess the theory here is that freeing
+	 * something sure as heck modifies it, so you
+	 * want to ban attempts to free it, but, alas,
+	 * if we make the "data" field of an "address"
+	 * structure not a "const", the compiler whines if
+	 * we try to make it point into the data for a packet,
+	 * as that's a "const" array (and should be, as dissectors
+	 * shouldn't trash it).
+	 *
+	 * So we cast the complaint into oblivion, and rely on
+	 * the fact that these addresses are known to have had
+	 * their data mallocated, i.e. they don't point into,
+	 * say, the middle of the data for a packet.
+	 */
+	g_free((gpointer)key->src.data);
+	g_free((gpointer)key->dst.data);
+
+	for (fd_head = value; fd_head != NULL; fd_head = fd_head->next) {
+		if(fd_head->data && !(fd_head->flags&FD_NOT_MALLOCED))
+			g_free(fd_head->data);
+	}
+
+	return TRUE;
+}
+
+/*
+ * For a reassembled-packet hash table entry, free the fragment data
+ * to which the value refers.
+ * (The actual value structures get freed by "reassemble_init()".)
+ */
+static gboolean
+free_all_reassembled_fragments(gpointer key_arg _U_, gpointer value,
+			       gpointer user_data _U_)
+{
+	fragment_data *fd_head;
+
+	for (fd_head = value; fd_head != NULL; fd_head = fd_head->next) {
+		if(fd_head->data && !(fd_head->flags&FD_NOT_MALLOCED)) {
+			g_free(fd_head->data);
+
+			/*
+			 * A reassembled packet is inserted into the
+			 * hash table once for every frame that made
+			 * up the reassembled packet; clear the data
+			 * pointer so that we only free the data the
+			 * first time we see it.
+			 */
+			fd_head->data = NULL;
+		}
+	}
+
+	return TRUE;
+}
+
+/*
+ * Initialize a fragment table.
+ */
+void
+fragment_table_init(GHashTable **fragment_table)
+{
+	if (*fragment_table != NULL) {
+		/*
+		 * The fragment hash table exists.
+		 *
+		 * Remove all entries and free fragment data for
+		 * each entry.  (The key and value data is freed
+		 * by "reassemble_init()".)
+		 */
+		g_hash_table_foreach_remove(*fragment_table,
+				free_all_fragments, NULL);
+	} else {
+		/* The fragment table does not exist. Create it */
+		*fragment_table = g_hash_table_new(fragment_hash,
+				fragment_equal);
+	}
+}
+
+void
+dcerpc_fragment_table_init(GHashTable **fragment_table)
+{
+       if (*fragment_table != NULL) {
+               /*
+                * The fragment hash table exists.
+                *
+                * Remove all entries and free fragment data for
+                * each entry.  (The key and value data is freed
+                * by "reassemble_init()".)
+                */
+               g_hash_table_foreach_remove(*fragment_table,
+                               free_all_fragments, NULL);
+       } else {
+               /* The fragment table does not exist. Create it */
+               *fragment_table = g_hash_table_new(dcerpc_fragment_hash,
+                               dcerpc_fragment_equal);
+       }
+}
+
+/*
+ * Initialize a reassembled-packet table.
+ */
+void
+reassembled_table_init(GHashTable **reassembled_table)
+{
+	if (*reassembled_table != NULL) {
+		/*
+		 * The reassembled-packet hash table exists.
+		 *
+		 * Remove all entries and free reassembled packet
+		 * data for each entry.  (The key data is freed
+		 * by "reassemble_init()".)
+		 */
+		g_hash_table_foreach_remove(*reassembled_table,
+				free_all_reassembled_fragments, NULL);
+	} else {
+		/* The fragment table does not exist. Create it */
+		*reassembled_table = g_hash_table_new(reassembled_hash,
+				reassembled_equal);
+	}
+}
+
+/*
+ * Free up all space allocated for fragment keys and data and
+ * reassembled keys.
+ */
+void
+reassemble_init(void)
+{
+	if (fragment_key_chunk != NULL)
+		g_mem_chunk_destroy(fragment_key_chunk);
+	if (dcerpc_fragment_key_chunk != NULL)
+		g_mem_chunk_destroy(dcerpc_fragment_key_chunk);
+	if (fragment_data_chunk != NULL)
+		g_mem_chunk_destroy(fragment_data_chunk);
+	if (reassembled_key_chunk != NULL)
+		g_mem_chunk_destroy(reassembled_key_chunk);
+	fragment_key_chunk = g_mem_chunk_new("fragment_key_chunk",
+	    sizeof(fragment_key),
+	    fragment_init_count * sizeof(fragment_key),
+	    G_ALLOC_AND_FREE);
+	dcerpc_fragment_key_chunk = g_mem_chunk_new("dcerpc_fragment_key_chunk",
+	    sizeof(dcerpc_fragment_key),
+	    fragment_init_count * sizeof(dcerpc_fragment_key),
+	    G_ALLOC_AND_FREE);
+	fragment_data_chunk = g_mem_chunk_new("fragment_data_chunk",
+	    sizeof(fragment_data),
+	    fragment_init_count * sizeof(fragment_data),
+	    G_ALLOC_ONLY);
+	reassembled_key_chunk = g_mem_chunk_new("reassembled_key_chunk",
+	    sizeof(reassembled_key),
+	    fragment_init_count * sizeof(reassembled_key),
+	    G_ALLOC_AND_FREE);
+}
+
+/* This function cleans up the stored state and removes the reassembly data and
+ * (with one exception) all allocated memory for matching reassembly.
+ *
+ * The exception is :
+ * If the PDU was already completely reassembled, then the buffer containing the
+ * reassembled data WILL NOT be free()d, and the pointer to that buffer will be
+ * returned.
+ * Othervise the function will return NULL.
+ *
+ * So, if you call fragment_delete and it returns non-NULL, YOU are responsible to
+ * g_free() that buffer.
+ */
+unsigned char *
+fragment_delete(packet_info *pinfo, guint32 id, GHashTable *fragment_table)
+{
+	fragment_data *fd_head, *fd;
+	fragment_key key;
+	unsigned char *data=NULL;
+
+	/* 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==NULL){
+		/* We do not recognize this as a PDU we have seen before. return*/
+		return NULL;
+	}
+
+	data=fd_head->data;
+	/* loop over all partial fragments and free any buffers */
+	for(fd=fd_head->next;fd;){
+		fragment_data *tmp_fd;
+		tmp_fd=fd->next;
+
+		if( !(fd->flags&FD_NOT_MALLOCED) )
+			g_free(fd->data);
+		g_mem_chunk_free(fragment_data_chunk, fd);
+		fd=tmp_fd;
+	}
+	g_mem_chunk_free(fragment_data_chunk, fd_head);
+	g_hash_table_remove(fragment_table, &key);
+
+	return data;
+}
+
+/* This function is used to check if there is partial or completed reassembly state
+ * matching this packet. I.e. Are there reassembly going on or not for this packet?
+ */
+fragment_data *
+fragment_get(packet_info *pinfo, 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);
+
+	return fd_head;
+}
+
+/* This function can be used to explicitely set the total length (if known)
+ * for reassembly of a PDU.
+ * This is useful for reassembly of PDUs where one may have the total length specified
+ * in the first fragment instead of as for, say, IPv4 where a flag indicates which
+ * is the last fragment.
+ *
+ * Such protocols might fragment_add with a more_frags==TRUE for every fragment
+ * and just tell the reassembly engine the expected total length of the reassembled data
+ * using fragment_set_tot_len immediately after doing fragment_add for the first packet.
+ *
+ * note that for FD_BLOCKSEQUENCE tot_len is the index for the tail fragment.
+ * i.e. since the block numbers start at 0, if we specify tot_len==2, that
+ * actually means we want to defragment 3 blocks, block 0, 1 and 2.
+ */
+void
+fragment_set_tot_len(packet_info *pinfo, guint32 id, GHashTable *fragment_table,
+		     guint32 tot_len)
+{
+	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);
+
+	if(fd_head){
+		fd_head->datalen = tot_len;
+	}
+
+	return;
+}
+
+guint32
+fragment_get_tot_len(packet_info *pinfo, 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);
+
+	if(fd_head){
+		return fd_head->datalen;
+	}
+
+	return 0;
+}
+
+
+/* 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(packet_info *pinfo, 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);
+
+	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.
+ */
+static void
+fragment_unhash(GHashTable *fragment_table, fragment_key *key)
+{
+	/*
+	 * Free up the copies of the addresses from the old key.
+	 */
+	g_free((gpointer)key->src.data);
+	g_free((gpointer)key->dst.data);
+
+	/*
+	 * Remove the entry from the fragment table.
+	 */
+	g_hash_table_remove(fragment_table, key);
+
+	/*
+	 * Free the key itself.
+	 */
+	g_mem_chunk_free(fragment_key_chunk, key);
+}
+
+/*
+ * 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, packet_info *pinfo,
+	     GHashTable *reassembled_table, 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 = g_mem_chunk_alloc(reassembled_key_chunk);
+		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 = g_mem_chunk_alloc(reassembled_key_chunk);
+			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, int offset,
+	     packet_info *pinfo, guint32 frag_offset,
+	     guint32 frag_data_len, 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_mem_chunk_alloc(fragment_data_chunk);
+	fd->next = NULL;
+	fd->flags = 0;
+	fd->frame = pinfo->fd->num;
+	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_head->flags &= (~FD_TOOLONGFRAGMENT) & (~FD_MULTIPLETAILS);
+		fd_head->datalen=0;
+	}
+
+	if (!more_frags) {
+		/*
+		 * This is the tail fragment in the sequence.
+		 */
+		if (fd_head->datalen) {
+			/* 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. Somethings 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;
+		}
+	}
+
+
+
+
+	/* 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 its not too long */
+		if (fd->offset + fd->len > fd_head->datalen) {
+			fd->flags      |= FD_TOOLONGFRAGMENT;
+			fd_head->flags |= FD_TOOLONGFRAGMENT;
+			LINK_FRAG(fd_head,fd);
+			return TRUE;
+		}
+		/* make sure it doesnt conflict with previous data */
+		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;
+			LINK_FRAG(fd_head,fd);
+			return TRUE;
+		}
+		/* 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->datalen) ){
+		/* 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.
+	 */
+	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)) {
+		/* we have not 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) {
+			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;
+				}
+			}
+			/* dfpos is always >= than fd_i->offset */
+			/* No gaps can exist here, max_loop(above) does this */
+			if( fd_i->offset+fd_i->len > dfpos )
+				memcpy(fd_head->data+dfpos, fd_i->data+(dfpos-fd_i->offset),
+					fd_i->len-(dfpos-fd_i->offset));
+			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));
+		}
+	}
+
+	if( old_data )
+		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;
+}
+
+fragment_data *
+fragment_add_common(tvbuff_t *tvb, int offset, packet_info *pinfo, guint32 id,
+	     GHashTable *fragment_table, guint32 frag_offset,
+	     guint32 frag_data_len, gboolean more_frags,
+	     gboolean check_already_added)
+{
+	fragment_key key, *new_key;
+	fragment_data *fd_head;
+	fragment_data *fd_item;
+	gboolean already_added=pinfo->fd->flags.visited;
+
+	/* 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);
+
+	/*
+	 * "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.
+	 */
+	if (!already_added && check_already_added && fd_head != NULL) {
+		for(fd_item=fd_head->next;fd_item;fd_item=fd_item->next){
+			if(pinfo->fd->num==fd_item->frame){
+				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=g_mem_chunk_alloc(fragment_data_chunk);
+
+		/* head/first structure in list only holds no other data than
+                 * 'datalen' then we don't have to change the head of the list
+                 * even if we want to keep it sorted
+                 */
+		fd_head->next=NULL;
+		fd_head->datalen=0;
+		fd_head->offset=0;
+		fd_head->len=0;
+		fd_head->flags=0;
+		fd_head->data=NULL;
+		fd_head->reassembled_in=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_mem_chunk_alloc(fragment_key_chunk);
+		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, int offset, packet_info *pinfo, guint32 id,
+	     GHashTable *fragment_table, guint32 frag_offset,
+	     guint32 frag_data_len, 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, int offset, packet_info *pinfo,
+			 guint32 id, GHashTable *fragment_table,
+			 guint32 frag_offset, guint32 frag_data_len,
+			 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, int offset, packet_info *pinfo,
+	     guint32 id, GHashTable *fragment_table,
+	     GHashTable *reassembled_table, guint32 frag_offset,
+	     guint32 frag_data_len, 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;
+
+	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=g_mem_chunk_alloc(fragment_data_chunk);
+
+		/* head/first structure in list only holds no other data than
+                 * 'datalen' then we don't have to change the head of the list
+                 * even if we want to keep it sorted
+                 */
+		fd_head->next=NULL;
+		fd_head->datalen=0;
+		fd_head->offset=0;
+		fd_head->len=0;
+		fd_head->flags=0;
+		fd_head->data=NULL;
+		fd_head->reassembled_in=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_mem_chunk_alloc(fragment_key_chunk);
+		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;
+	}
+}
+
+/*
+ * 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, int offset,
+	     packet_info *pinfo, guint32 frag_number,
+	     guint32 frag_data_len, gboolean more_frags)
+{
+	fragment_data *fd;
+	fragment_data *fd_i;
+	fragment_data *last_fd;
+	guint32 max, dfpos, size;
+
+	/* create new fd describing this fragment */
+	fd = g_mem_chunk_alloc(fragment_data_chunk);
+	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->datalen) {
+			/* 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. Somethings 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;
+		}
+	}
+
+	/* 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 doesnt conflict with previous data */
+		dfpos=0;
+		last_fd=NULL;
+		for (fd_i=fd_head->next;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;
+			}
+			g_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?
+	 */
+	fd->data = g_malloc(fd->len);
+	tvb_memcpy(tvb, fd->data, offset, fd->len);
+	LINK_FRAG(fd_head,fd);
+
+
+	if( !(fd_head->datalen) ){
+		/* 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.
+	 */
+	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
+         */
+	size=0;
+	last_fd=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;
+	}
+	fd_head->data = g_malloc(size);
+	fd_head->len = size;		/* record size for caller	*/
+
+	/* add all data fragments */
+	last_fd=NULL;
+	for (dfpos=0,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){
+	      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->datalen)
+		  || memcmp(last_fd->data, fd_i->data, last_fd->len) ){
+			fd->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->data){
+	    g_free(fd_i->data);
+	    fd_i->data=NULL;
+	  }
+	}
+
+	/* 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;
+}
+
+/*
+ * 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, int offset, packet_info *pinfo, guint32 id,
+	     GHashTable *fragment_table, guint32 frag_number,
+	     guint32 frag_data_len, gboolean more_frags)
+{
+	fragment_key key, *new_key;
+	fragment_data *fd_head;
+
+	/* 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);
+
+	/* 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=g_mem_chunk_alloc(fragment_data_chunk);
+
+		/* head/first structure in list only holds no other data than
+                 * 'datalen' then we don't have to change the head of the list
+                 * even if we want to keep it sorted
+                 */
+		fd_head->next=NULL;
+		fd_head->datalen=0;
+		fd_head->offset=0;
+		fd_head->len=0;
+		fd_head->flags=FD_BLOCKSEQUENCE;
+		fd_head->data=NULL;
+		fd_head->reassembled_in=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_mem_chunk_alloc(fragment_key_chunk);
+		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_seq_work(fd_head, tvb, offset, pinfo,
+				  frag_number, frag_data_len, more_frags)) {
+		/*
+		 * Reassembly is complete.
+		 */
+		return fd_head;
+	} else {
+		/*
+		 * Reassembly isn't complete.
+		 */
+		return NULL;
+	}
+}
+
+fragment_data *
+fragment_add_dcerpc(tvbuff_t *tvb, int offset, packet_info *pinfo, guint32 id,
+                    void *v_act_id,
+                    GHashTable *fragment_table, guint32 frag_number,
+                    guint32 frag_data_len, gboolean more_frags)
+{
+       dcerpc_fragment_key key, *new_key;
+       fragment_data *fd_head;
+       e_uuid_t *act_id = (e_uuid_t *)v_act_id;
+
+       /* create key to search hash with */
+       key.src = pinfo->src;
+       key.dst = pinfo->dst;
+       key.id  = id;
+       key.act_id  = *act_id;
+
+       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=g_mem_chunk_alloc(fragment_data_chunk);
+
+               /* head/first structure in list only holds no other data than
+                 * 'datalen' then we don't have to change the head of the list
+                 * even if we want to keep it sorted
+                 */
+               fd_head->next=NULL;
+               fd_head->datalen=0;
+               fd_head->offset=0;
+               fd_head->len=0;
+               fd_head->flags=FD_BLOCKSEQUENCE;
+               fd_head->data=NULL;
+               fd_head->reassembled_in=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_mem_chunk_alloc(dcerpc_fragment_key_chunk);
+               COPY_ADDRESS(&new_key->src, &key.src);
+               COPY_ADDRESS(&new_key->dst, &key.dst);
+               new_key->id = key.id;
+               new_key->act_id = key.act_id;
+               g_hash_table_insert(fragment_table, new_key, fd_head);
+       }
+
+       if (fragment_add_seq_work(fd_head, tvb, offset, pinfo,
+                                 frag_number, frag_data_len, more_frags)) {
+               /*
+                * 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, and:
+ *
+ *	if "more_frags" is false and "frag_802_11_hack" is true, the
+ *	structure is not added to the hash table, and not given any
+ *	fragments to refer to, but is just returned - this is a special
+ *	hack for the 802.11 dissector (see packet-80211.c);
+ *
+ *	otherwise, this fragment is added to the linked list of fragments
+ *	for this packet, and the "fragment_data" structure is put into
+ *	the hash table.
+ *
+ * Otherwise, this fragment is just added to the linked list of fragments
+ * for this packet.
+ *
+ * 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.
+ *
+ * If this is the first fragment we've seen, and "more_frags" is false
+ * and "frag_802_11_hack" is true, "fragment_add_seq_check_work()" does
+ * nothing to the fragment data list, and returns a pointer to the head
+ * of that (empty) list.
+ *
+ * Otherwise, it returns NULL.
+ */
+static fragment_data *
+fragment_add_seq_check_work(tvbuff_t *tvb, int offset, packet_info *pinfo,
+	     guint32 id, GHashTable *fragment_table,
+	     GHashTable *reassembled_table, guint32 frag_number,
+	     guint32 frag_data_len, gboolean more_frags,
+	     gboolean no_frag_number, gboolean frag_802_11_hack)
+{
+	reassembled_key reass_key;
+	fragment_key key, *new_key, *old_key;
+	gpointer orig_key, value;
+	fragment_data *fd_head, *fd;
+
+	/*
+	 * 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;
+
+	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=g_mem_chunk_alloc(fragment_data_chunk);
+
+		/* head/first structure in list only holds no other data than
+                 * 'datalen' then we don't have to change the head of the list
+                 * even if we want to keep it sorted
+                 */
+		fd_head->next=NULL;
+		fd_head->datalen=0;
+		fd_head->offset=0;
+		fd_head->len=0;
+		fd_head->flags=FD_BLOCKSEQUENCE;
+		fd_head->data=NULL;
+		fd_head->reassembled_in=0;
+
+		if ((no_frag_number || frag_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
+			 * add the fragment to the table of reassembled
+			 * packets, and return a pointer to the head of
+			 * the list.
+			 */
+			fragment_reassembled(fd_head, pinfo,
+			       reassembled_table, id);
+			return fd_head;
+		}
+
+		/*
+		 * 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_mem_chunk_alloc(fragment_key_chunk);
+		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 */
+
+		/*
+		 * If we weren't given an initial fragment number,
+		 * make it 0.
+		 */
+		if (no_frag_number)
+			frag_number = 0;
+	} else {
+		/*
+		 * We found it.
+		 */
+		fd_head = value;
+
+		/*
+		 * If we weren't given an initial fragment number,
+		 * use the next expected fragment number as the fragment
+		 * number for this fragment.
+		 */
+		if (no_frag_number) {
+			for (fd = fd_head; fd != NULL; fd = fd->next) {
+				if (fd->next == NULL)
+					frag_number = fd->offset + 1;
+			}
+		}
+	}
+
+	/*
+	 * 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 (!tvb_bytes_exist(tvb, offset, frag_data_len)) {
+		if (!more_frags) {
+			/*
+			 * 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);
+		}
+		return frag_number == 0 ? fd_head : NULL;
+	}
+
+	if (fragment_add_seq_work(fd_head, tvb, offset, pinfo,
+				  frag_number, 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;
+	}
+}
+
+fragment_data *
+fragment_add_seq_check(tvbuff_t *tvb, int offset, packet_info *pinfo,
+	     guint32 id, GHashTable *fragment_table,
+	     GHashTable *reassembled_table, guint32 frag_number,
+	     guint32 frag_data_len, gboolean more_frags)
+{
+	return fragment_add_seq_check_work(tvb, offset, pinfo, id,
+	    fragment_table, reassembled_table, frag_number, frag_data_len,
+	    more_frags, FALSE, FALSE);
+}
+
+fragment_data *
+fragment_add_seq_802_11(tvbuff_t *tvb, int offset, packet_info *pinfo,
+	     guint32 id, GHashTable *fragment_table,
+	     GHashTable *reassembled_table, guint32 frag_number,
+	     guint32 frag_data_len, gboolean more_frags)
+{
+	return fragment_add_seq_check_work(tvb, offset, pinfo, id,
+	    fragment_table, reassembled_table, frag_number, frag_data_len,
+	    more_frags, FALSE, TRUE);
+}
+
+fragment_data *
+fragment_add_seq_next(tvbuff_t *tvb, int offset, packet_info *pinfo,
+	     guint32 id, GHashTable *fragment_table,
+	     GHashTable *reassembled_table, guint32 frag_data_len,
+	     gboolean more_frags)
+{
+	return fragment_add_seq_check_work(tvb, offset, pinfo, id,
+	    fragment_table, reassembled_table, 0, frag_data_len,
+	    more_frags, TRUE, FALSE);
+}
+
+/*
+ * 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, int offset, packet_info *pinfo,
+    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;
+
+	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);
+			} else {
+				update_col_info = !show_fragment_tree(fd_head,
+				    fit, tree, pinfo, next_tvb);
+			}
+		} else {
+			/*
+			 * No.
+			 * Return a tvbuff with the payload.
+			 */
+			next_tvb = tvb_new_subset(tvb, offset, -1, -1);
+			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.
+ */
+static void
+show_fragment(fragment_data *fd, int offset, const fragment_items *fit,
+    proto_tree *ft, tvbuff_t *tvb)
+{
+	proto_item *fei=NULL;
+	int hf;
+
+	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 bytes)",
+			fd->frame,
+			offset,
+			offset+fd->len-1,
+			fd->len);
+	}
+	PROTO_ITEM_SET_GENERATED(fei);
+	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)
+{
+	fragment_data *fd;
+	proto_tree *ft;
+	proto_item *fi;
+
+	/* It's not fragmented. */
+	pinfo->fragmented = FALSE;
+
+	fi = proto_tree_add_item(tree, *(fit->hf_fragments),
+	    tvb, 0, -1, FALSE);
+	PROTO_ITEM_SET_GENERATED(fi);
+
+	ft = proto_item_add_subtree(fi, *(fit->ett_fragments));
+	for (fd = fd_head->next; fd != NULL; fd = fd->next)
+		show_fragment(fd, fd->offset, fit, ft, tvb);
+
+	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)
+{
+	guint32 offset, next_offset;
+	fragment_data *fd, *last_fd;
+	proto_tree *ft;
+	proto_item *fi;
+
+	/* It's not fragmented. */
+	pinfo->fragmented = FALSE;
+
+	fi = proto_tree_add_item(tree, *(fit->hf_fragments),
+	    tvb, 0, -1, FALSE);
+	PROTO_ITEM_SET_GENERATED(fi);
+	ft = proto_item_add_subtree(fi, *(fit->ett_fragments));
+	offset = 0;
+	next_offset = 0;
+	last_fd = NULL;
+	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, tvb);
+	}
+
+	return show_fragment_errs_in_col(fd_head, fit, pinfo);
+}