src/dissector.c

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * By Daniel Borkmann <daniel@netsniff-ng.org>
   4  * Copyright 2009, 2010, 2011, 2012 Daniel Borkmann.
   5  * Subject to the GPL, version 2.
   6  */
   7
   8 #include <stdint.h>
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11
  12 #include "built_in.h"
  13 #include "tprintf.h"
  14 #include "dissector.h"
  15 #include "dissector_eth.h"
  16 #include "pkt_buff.h"
  17 #include "proto_struct.h"
  18
  19 int dissector_set_print_type(void *ptr, int type)
  20 {
  21         struct protocol *proto;
  22
  23         for (proto = (struct protocol *) ptr; proto; proto = proto->next) {
  24                 switch (type) {
  25                 case FNTTYPE_PRINT_NORM:
  26                         proto->process = proto->print_full;
  27                         break;
  28                 case FNTTYPE_PRINT_LESS:
  29                         proto->process = proto->print_less;
  30                         break;
  31                 case FNTTYPE_PRINT_HEX:
  32                 case FNTTYPE_PRINT_ASCII:
  33                 case FNTTYPE_PRINT_NONE:
  34                 default:
  35                         proto->process = NULL;
  36                         break;
  37                 }
  38         }
  39
  40         return 0;
  41 }
  42
  43 static void dissector_main(struct pkt_buff *pkt, struct protocol *start,
  44                            struct protocol *end)
  45 {
  46         struct protocol *proto;
  47
  48         for (pkt->proto = start; pkt->proto; ) {
  49                 if (unlikely(!pkt->proto->process))
  50                         break;
  51
  52                 proto = pkt->proto;
  53                 pkt->proto = NULL;
  54                 proto->process(pkt);
  55         }
  56
  57         if (end && likely(end->process))
  58                 end->process(pkt);
  59 }
  60
  61 void dissector_entry_point(uint8_t *packet, size_t len, int linktype, int mode)
  62 {
  63         struct protocol *proto_start = NULL;
  64         struct protocol *proto_end = NULL;
  65         struct pkt_buff *pkt = NULL;
  66
  67         if (mode == FNTTYPE_PRINT_NONE)
  68                 return;
  69
  70         pkt = pkt_alloc(packet, len);
  71
  72         switch (linktype) {
  73         case LINKTYPE_EN10MB:
  74                 proto_start = dissector_get_ethernet_entry_point();
  75                 proto_end = dissector_get_ethernet_exit_point();
  76                 break;
  77         default:
  78                 panic("Linktype not supported!\n");
  79         };
  80
  81         dissector_main(pkt, proto_start, proto_end);
  82
  83         switch (mode) {
  84         case FNTTYPE_PRINT_HEX:
  85                 hex(pkt);
  86                 break;
  87         case FNTTYPE_PRINT_ASCII:
  88                 ascii(pkt);
  89                 break;
  90         }
  91
  92         tprintf_flush();
  93         pkt_free(pkt);
  94 }
  95
  96 void dissector_init_all(int fnttype)
  97 {
  98         dissector_init_ethernet(fnttype);
  99 }
 100
 101 void dissector_cleanup_all(void)
 102 {
 103         dissector_cleanup_ethernet();
 104 }