dissector.c

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * Copyright 2009, 2010, 2011, 2012 Daniel Borkmann.
   4  * Subject to the GPL, version 2.
   5  */
   6
   7 #include <stdint.h>
   8 #include <stdlib.h>
   9 #include <unistd.h>
  10
  11 #include "built_in.h"
  12 #include "tprintf.h"
  13 #include "pkt_buff.h"
  14 #include "proto.h"
  15 #include "dissector.h"
  16 #include "dissector_eth.h"
  17 #include "dissector_80211.h"
  18
  19 int dissector_set_print_type(void *ptr, int type)
  20 {
  21         struct protocol *proto;
  22
  23         for (proto = ptr; proto; proto = proto->next) {
  24                 switch (type) {
  25                 case PRINT_NORM:
  26                         proto->process = proto->print_full;
  27                         break;
  28                 case PRINT_LESS:
  29                         proto->process = proto->print_less;
  30                         break;
  31                 default:
  32                         proto->process = NULL;
  33                         break;
  34                 }
  35         }
  36
  37         return 0;
  38 }
  39
  40 static void dissector_main(struct pkt_buff *pkt, struct protocol *start,
  41                            struct protocol *end)
  42 {
  43         struct protocol *proto;
  44
  45         if (!start)
  46                 return;
  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, *proto_end;
  64         struct pkt_buff *pkt;
  65
  66         if (mode == PRINT_NONE)
  67                 return;
  68
  69         pkt = pkt_alloc(packet, len);
  70
  71         switch (linktype) {
  72         case LINKTYPE_EN10MB:
  73         case ___constant_swab32(LINKTYPE_EN10MB):
  74                 proto_start = dissector_get_ethernet_entry_point();
  75                 proto_end = dissector_get_ethernet_exit_point();
  76                 break;
  77         case LINKTYPE_IEEE802_11:
  78         case ___constant_swab32(LINKTYPE_IEEE802_11):
  79                 proto_start = dissector_get_ieee80211_entry_point();
  80                 proto_end = dissector_get_ieee80211_exit_point();
  81                 break;
  82         default:
  83                 proto_start = &none_ops;
  84                 proto_end = NULL;
  85                 break;
  86         };
  87
  88         dissector_main(pkt, proto_start, proto_end);
  89
  90         switch (mode) {
  91         case PRINT_HEX:
  92                 hex(pkt);
  93                 break;
  94         case PRINT_ASCII:
  95                 ascii(pkt);
  96                 break;
  97         case PRINT_HEX_ASCII:
  98                 hex_ascii(pkt);
  99                 break;
 100         }
 101
 102         tprintf_flush();
 103         pkt_free(pkt);
 104 }
 105
 106 void dissector_init_all(int fnttype)
 107 {
 108         dissector_init_ethernet(fnttype);
 109         dissector_init_ieee80211(fnttype);
 110 }
 111
 112 void dissector_cleanup_all(void)
 113 {
 114         dissector_cleanup_ethernet();
 115         dissector_cleanup_ieee80211();
 116 }