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 = (struct protocol *) ptr;
  22
  23         while (proto != NULL) {
  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                 default:
  32                 case FNTTYPE_PRINT_NONE:
  33                         proto->process = NULL;
  34                         break;
  35                 }
  36
  37                 proto = proto->next;
  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 != NULL;) {
  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 != NULL)
  58                 if (likely(end->process))
  59                         end->process(pkt);
  60
  61         tprintf_flush();
  62 }
  63
  64 void dissector_entry_point(uint8_t *packet, size_t len, int linktype, int mode)
  65 {
  66         struct protocol *proto_start = NULL;
  67         struct protocol *proto_end = NULL;
  68         struct pkt_buff *pkt = NULL;
  69
  70         if (mode == FNTTYPE_PRINT_NONE)
  71                 return;
  72
  73         pkt = pkt_alloc(packet, len);
  74
  75         switch (linktype) {
  76         case LINKTYPE_EN10MB:
  77                 proto_start = dissector_get_ethernet_entry_point();
  78                 proto_end = dissector_get_ethernet_exit_point();
  79                 break;
  80         default:
  81                 panic("Linktype not supported!\n");
  82         };
  83
  84         dissector_main(pkt, proto_start, proto_end);
  85
  86         pkt_free(pkt);
  87 }
  88
  89 void dissector_init_all(int fnttype)
  90 {
  91         dissector_init_ethernet(fnttype);
  92 }
  93
  94 void dissector_cleanup_all(void)
  95 {
  96         dissector_cleanup_ethernet();
  97 }