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 #include "dissector_netlink.h"
  19 #include "linktype.h"
  20
  21 int dissector_set_print_type(void *ptr, int type)
  22 {
  23         struct protocol *proto;
  24
  25         for (proto = ptr; proto; proto = proto->next) {
  26                 switch (type) {
  27                 case PRINT_NORM:
  28                         proto->process = proto->print_full;
  29                         break;
  30                 case PRINT_LESS:
  31                         proto->process = proto->print_less;
  32                         break;
  33                 default:
  34                         proto->process = NULL;
  35                         break;
  36                 }
  37         }
  38
  39         return 0;
  40 }
  41
  42 static void dissector_main(struct pkt_buff *pkt, struct protocol *start,
  43                            struct protocol *end)
  44 {
  45         struct protocol *proto;
  46
  47         if (!start)
  48                 return;
  49
  50         for (pkt->proto = start; pkt->proto; ) {
  51                 if (unlikely(!pkt->proto->process))
  52                         break;
  53
  54                 proto = pkt->proto;
  55                 pkt->proto = NULL;
  56                 proto->process(pkt);
  57         }
  58
  59         if (end && likely(end->process))
  60                 end->process(pkt);
  61 }
  62
  63 void dissector_entry_point(uint8_t *packet, size_t len, int linktype, int mode)
  64 {
  65         struct protocol *proto_start, *proto_end;
  66         struct pkt_buff *pkt;
  67
  68         if (mode == PRINT_NONE)
  69                 return;
  70
  71         pkt = pkt_alloc(packet, len);
  72
  73         switch (linktype) {
  74         case LINKTYPE_EN10MB:
  75         case ___constant_swab32(LINKTYPE_EN10MB):
  76                 proto_start = dissector_get_ethernet_entry_point();
  77                 proto_end = dissector_get_ethernet_exit_point();
  78                 break;
  79         case LINKTYPE_IEEE802_11:
  80         case ___constant_swab32(LINKTYPE_IEEE802_11):
  81                 proto_start = dissector_get_ieee80211_entry_point();
  82                 proto_end = dissector_get_ieee80211_exit_point();
  83                 break;
  84         case LINKTYPE_NETLINK:
  85         case ___constant_swab32(LINKTYPE_NETLINK):
  86                 proto_start = dissector_get_netlink_entry_point();
  87                 proto_end = dissector_get_netlink_exit_point();
  88                 break;
  89         default:
  90                 proto_start = &none_ops;
  91                 proto_end = NULL;
  92                 break;
  93         };
  94
  95         dissector_main(pkt, proto_start, proto_end);
  96
  97         switch (mode) {
  98         case PRINT_HEX:
  99                 hex(pkt);
 100                 break;
 101         case PRINT_ASCII:
 102                 ascii(pkt);
 103                 break;
 104         case PRINT_HEX_ASCII:
 105                 hex_ascii(pkt);
 106                 break;
 107         }
 108
 109         tprintf_flush();
 110         pkt_free(pkt);
 111 }
 112
 113 void dissector_init_all(int fnttype)
 114 {
 115         dissector_init_ethernet(fnttype);
 116         dissector_init_ieee80211(fnttype);
 117         dissector_init_netlink(fnttype);
 118 }
 119
 120 void dissector_cleanup_all(void)
 121 {
 122         dissector_cleanup_ethernet();
 123         dissector_cleanup_ieee80211();
 124         dissector_cleanup_netlink();
 125 }