packet reassembly not succesful

Hi

Any one can help me on this?

Hi Afrim

you mean this? in reassemble.c ?

  tvbuff_t *
process_reassembled_data(tvbuff_t *tvb, const int offset,   packet_info *pinfo,
const char *name, fragment_head *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, and set
* 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.
*/
next_tvb = tvb_new_chain(tvb, fd_head->tvb_data);

    /* 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;

}

Disclaimer: I have not checked your code… Take a look at packet-sccp.c I think it has a pretty straight forward implementation of reassembly.

Hi Anders i have followed thew same steps and i have a condition like

    mte_frag_msg = fragment_add_seq_next(&mte_reassembly_table,next_tvb, offset_payload, pinfo, mte_seqid, NULL, rem_length, more_frags);

                                    save_fragmented = pinfo->fragmented;
                                    pinfo->fragmented = TRUE;
mte_tvb = process_reassembled_data(next_tvb, offset_payload, pinfo, "mte Reassembled PDU", mte_frag_msg, &mte_frag_items, NULL, FT_BCnPDU_tree );

if (mte_frag_msg) { /* Reassembled */
            try_tvb=mte_tvb;
            col_append_str(pinfo->cinfo, COL_INFO,"(Message reassembled) ");
                } else { /* Not last packet of reassembled message */
                        col_append_str(pinfo->cinfo, COL_INFO,"(Message fragment) ");

}
if (try_tvb){
 ALSIGPDU(try_tvb, pinfo, tree);

} else {
ALSIGPDU(next_tvb, pinfo, tree);
}

Iam getting always Message Fragmented in col info. looks like Some thing wrong and a majot step i have missed. mte_frag_msg itself not succesful. is ther any steps for diplaying in seperate tab as Reassembled data ?? Please Help!

Are you stepping the sequence number for each packet and setting more_fragments to false for the last packet?

HI

My Sequence number set to 0 Zero. Because my packets messages always comes in order. More frags i have set to TRUE and in the last packet i made it FALSE.

one more doubt! my pdu length bit is 12 bit and when i stor in 32 bit gint. How one byte by byte the data stord in table? How does it copy the data into the table?

Hi anyone help me on this please.

Hi

Anders , ANyone Help Me please!

I Have tried setting up seq number 1,2,3 and tried . still same.

     mte_frag_msg = fragment_add_seq_next(&mte_reassembly_table,next_tvb, offset_payload, pinfo, mte_seqid, NULL, rem_length, more_frags);

mte_tvb = process_reassembled_data(next_tvb, offset_payload, pinfo, &quot;mte Reassembled PDU&quot;, mte_frag_msg, &amp;mte_frag_items, NULL, FT_BCnPDU_tree );</code></pre><p>do i need to create GHASh Table ?</p><p>My table decleration is</p><pre><code>   static reassembly_table mte_reassembly_table;</code></pre><p>table init is</p><pre><code>    static void mte_init_protocol(void)
                             {

         reassembly_table_init(&amp;mte_reassembly_table, &amp;addresses_reassembly_table_functions);
                    }</code></pre><p>please help.</p></div><div id="comment-38271-info" class="comment-info"><span class="comment-age">(01 Dec '14, 18:20)</span> <span class="comment-user userinfo">umar</span></div></div><span id="38279"></span><div id="comment-38279" class="comment not_top_scorer"><div id="post-38279-score" class="comment-score"></div><div class="comment-text"><p>In my opinion you don't even need sequence number. i've done my own reassemble without sequence number. Btw if your col_info shows "Message reassembled" it mean that the reassemble was successfull so "mte_frag_msg" is not NULL.</p></div><div id="comment-38279-info" class="comment-info"><span class="comment-age">(02 Dec '14, 05:52)</span> <span class="comment-user userinfo">Afrim</span></div></div><span id="38286"></span><div id="comment-38286" class="comment not_top_scorer"><div id="post-38286-score" class="comment-score"></div><div class="comment-text"><p>Hi I got the "message Fragmengted" in beginning of message and continuation of message. In end of message iam geting error "not reassembled" . I have the issue of counting the remaining length. In beginning of message iam haing the length of the PDU . the length iam passing to fragment_add_seq is guint 32</p><pre><code>                mte_frag_msg = fragment_add_seq_next(&amp;mte_reassembly_table,next_tvb, offset_payload, pinfo, mte_seqid, NULL, rem_length, more_frags);</code></pre><p>Is there any method to count in this value ? Iam not getting it.</p></div><div id="comment-38286-info" class="comment-info"><span class="comment-age">(02 Dec '14, 18:36)</span> <span class="comment-user userinfo">umar</span></div></div><span id="38294"></span><div id="comment-38294" class="comment not_top_scorer"><div id="post-38294-score" class="comment-score"></div><div class="comment-text"><p>Hi Afrim,</p><p>iam not creating a tvb in beginning of message and continuation of message. Only in End of message (last message)i have created a tvb and proceess_reassemble. iam not getting message reassembled in colinfo.</p><p>Here i got problem. tvb itself not created because</p><p>my code like this</p><pre><code>         if (mte_tvb) { /* Reassembled */

col_append_str(pinfo->cinfo, COL_INFO,"(Message reassembled) ");          

} else { /* Not successful reassembled message */
col_append_str(pinfo->cinfo, COL_INFO,"(Message fragment ) ");
}

so tvb itself not created. please suggest.