Question

我在UDP上开发了一个自定义解剖器，它使用PDCP层PDU RFC 2507选择性重复ARQ机制进行分段和重组。我的留言包含消息的开头

      continuation of message and

      end of message

消息不按顺序发送，并且基于序列号和消息ID我需要重新组装。我不知道我是否应该使用对话或

      add_fragment_seq_next or

      add_fragment_seq_check

请建议。我长期困扰这个

为什么我的代码不起作用？碎片本身不成功，因此重组不起作用。请提出建议！

 switch (stype) {
          case 0x00: // Continuation of Message
           msg_seqid = 2;
          rem_length = bctsdu_length;
        proto_tree_add_text(FT_BCnPDU_tree, next_tvb, offset_payload, rem_length, "PDU data : %d", rem_length);
break;

   case 0x01: // Beginning of Message
msg_seqid = 1;
proto_tree_add_text(BCnPDU_bom_tree, next_tvb, offset_payload, 2, "PDU Length : 0x%02x (%d)", pdu_len, pdu_len);
rem_length = tvb_length_remaining(next_tvb, offset_payload);
rem_length -= 2;
proto_tree_add_text(BCnPDU_bom_tree, next_tvb, offset_payload, rem_length, "PDU data  : %d ", rem_length);

break;

 case 0x02: // End of Message
msg_seqid = 3;
bctsdu_length += 2;
more_frags = FALSE;
rem_length = bctsdu_length;
rem_length -= 2;
proto_tree_add_text(FT_BCnPDU_tree, next_tvb, offset_payload, rem_length, "PDU data : %d", rem_length);
disable_CRC = 1;
break;

case 0x04: // Single Segment Message
---- // doesn't need fragment/reassembly
  break;


     }



    if (msg_seqid == 1 || msg_seqid == 2 || msg_seqid == 3) {
save_fragmented = pinfo->fragmented;
pinfo->fragmented = TRUE;
frag_msg = fragment_add_seq_check(&mns_reassembly_table,
                                  next_tvb,
                                  offset_payload,
                                  pinfo,
                                  mns_seqnum,
                                  NULL,
                                  mns_seqid,
                                  rem_length,
                                  more_frags);
if (frag_msg) {
    col_append_fstr(pinfo->cinfo, COL_INFO, " mns segment of a FRAGMENT PDU");
} else {
    col_append_fstr(pinfo->cinfo, COL_INFO, " FRAGMENT NOT DONE ");
}

}

  if (more_frags == FALSE) {
save_fragmented = pinfo->fragmented;
pinfo->fragmented = FALSE;

rass_tvb = process_reassembled_data(next_tvb,
                                    offset_payload,
                                    pinfo,
                                    "Reassembled Message",
                                    frag_msg,
                                    &mns_frag_items,
                                    NULL,
                                    FT_BCnPDU_tree);
if (rass_tvb) {
    col_append_str(pinfo->cinfo, COL_INFO, "(Message reassembled ) ");
    ALSIGPDU(rass_tvb, pinfo, FT_BCnPDU_tree);
}

}


    I am always getting the FRAGMENT NOT DONE error. Please Help

Wireshark片段失败

0 个答案: