tcpdump.c

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/*
 * Copyright (c) 2001, Swedish Institute of Computer Science.
 * All rights reserved. 
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions 
 * are met: 
 * 1. Redistributions of source code must retain the above copyright 
 *    notice, this list of conditions and the following disclaimer. 
 * 2. Redistributions in binary form must reproduce the above copyright 
 *    notice, this list of conditions and the following disclaimer in the 
 *    documentation and/or other materials provided with the distribution. 
 * 3. Neither the name of the Institute nor the names of its contributors 
 *    may be used to endorse or promote products derived from this software 
 *    without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
 * SUCH DAMAGE. 
 *
 * This file is part of the lwIP TCP/IP stack.
 * 
 * Author: Adam Dunkels <adam@sics.se>
 *
 * $Id: tcpdump.c 54 2016-01-11 01:29:55Z reddawg $
 */
 
#include <vfs/file.h>
#include <ubixos/kpanic.h>
  
#include "netif/tcpdump.h"
#include "net/ipv4/ip.h"
#include "net/tcp.h"
#include "net/udp.h"
#include "net/ipv4/inet.h"
 
fileDescriptor *file = NULL;
 
void tcpdump_init(void) {
  char *fname;
 
  fname = "tcpdump";
  file = fopen(fname, "wb");
  if(file == NULL) {
    kpanic("tcpdump_init: fopen\n");
    }
  }
 
void tcpdump(struct pbuf *p) {
/*
  struct ip_hdr *iphdr;
  struct tcp_hdr *tcphdr;
  struct udp_hdr *udphdr;
  char flags[5];
  int i;
  int len;
  int offset;
*/
  if (file == NULL) {
    return;
    }
  
  /*
  iphdr = p->payload;
  switch(IPH_PROTO(iphdr)) {
  case IP_PROTO_TCP:    
    tcphdr = (struct tcp_hdr *)((char *)iphdr + IP_HLEN);
    
    pbuf_header(p, -IP_HLEN);
    if(inet_chksum_pseudo(p, (struct ip_addr *)&(iphdr->src),
                          (struct ip_addr *)&(iphdr->dest),
                          IP_PROTO_TCP, p->tot_len) != 0) {
      DEBUGF(TCPDUMP_DEBUG, ("tcpdump: IP checksum failed!\n"));
      fprintf(file, "!chksum ");
    }
    
    i = 0;
    if(TCPH_FLAGS(tcphdr) & TCP_SYN) {
      flags[i++] = 'S';
    }
    if(TCPH_FLAGS(tcphdr) & TCP_PSH) {
      flags[i++] = 'P';
    }
    if(TCPH_FLAGS(tcphdr) & TCP_FIN) {
      flags[i++] = 'F';
    }
    if(TCPH_FLAGS(tcphdr) & TCP_RST) {
      flags[i++] = 'R';
    }
    if(i == 0) {
      flags[i++] = '.';
    }
    flags[i++] = 0;    
 
    
    
    fprintf(file, "%d.%d.%d.%d.%u > %d.%d.%d.%d.%u: ",
            (int)(ntohl(iphdr->src.addr) >> 24) & 0xff,
            (int)(ntohl(iphdr->src.addr) >> 16) & 0xff,
            (int)(ntohl(iphdr->src.addr) >> 8) & 0xff,
            (int)(ntohl(iphdr->src.addr) >> 0) & 0xff,
            ntohs(tcphdr->src),
          (int)(ntohl(iphdr->dest.addr) >> 24) & 0xff,
            (int)(ntohl(iphdr->dest.addr) >> 16) & 0xff,
            (int)(ntohl(iphdr->dest.addr) >> 8) & 0xff,
            (int)(ntohl(iphdr->dest.addr) >> 0) & 0xff,
            ntohs(tcphdr->dest));
    offset = TCPH_OFFSET(tcphdr) >> 4;
    
    len = ntohs(IPH_LEN(iphdr)) - offset * 4 - IP_HLEN;
    if(len != 0 || flags[0] != '.') {
      fprintf(file, "%s %lu:%lu(%u) ",
              flags,
              ntohl(tcphdr->seqno),
              ntohl(tcphdr->seqno) + len,
              len);
    }
    if(TCPH_FLAGS(tcphdr) & TCP_ACK) {
      fprintf(file, "ack %lu ",
              ntohl(tcphdr->ackno));
    }
    fprintf(file, "wnd %u\n",
            ntohs(tcphdr->wnd));
    
    fflush(file);
    
    pbuf_header(p, IP_HLEN);
    break;
    
  case IP_PROTO_UDP:    
    udphdr = (struct udp_hdr *)((char *)iphdr + IP_HLEN);
    
    pbuf_header(p, -IP_HLEN);
    if(inet_chksum_pseudo(p, (struct ip_addr *)&(iphdr->src),
                          (struct ip_addr *)&(iphdr->dest),
                          IP_PROTO_UDP, p->tot_len) != 0) {
      kprintf("tcpdump: IP checksum failed!\n");
      fprintf(file, "!chksum ");
    }
    
    fprintf(file, "%d.%d.%d.%d.%u > %d.%d.%d.%d.%u: ",
            (int)(ntohl(iphdr->src.addr) >> 24) & 0xff,
            (int)(ntohl(iphdr->src.addr) >> 16) & 0xff,
            (int)(ntohl(iphdr->src.addr) >> 8) & 0xff,
            (int)(ntohl(iphdr->src.addr) >> 0) & 0xff,
            ntohs(udphdr->src),
          (int)(ntohl(iphdr->dest.addr) >> 24) & 0xff,
            (int)(ntohl(iphdr->dest.addr) >> 16) & 0xff,
            (int)(ntohl(iphdr->dest.addr) >> 8) & 0xff,
            (int)(ntohl(iphdr->dest.addr) >> 0) & 0xff,
            ntohs(udphdr->dest));
    fprintf(file, "U ");
    len = ntohs(IPH_LEN(iphdr)) - sizeof(struct udp_hdr) - IP_HLEN;
    fprintf(file, " %d\n", len);
    
    fflush(file);
    
    pbuf_header(p, IP_HLEN);
    break;
 
  }
  */
  }
 
/***
 END
 ***/