src/proto_ipv6_routing.h

   1 /*
   2  * IPv6 Routing Header described in RFC2460
   3  * programmed by Markus Amend 2012 as a contribution to
   4  * netsniff-ng - the packet sniffing beast
   5  * Copyright 2012 Markus Amend.
   6  * Subject to the GPL, version 2.
   7  */
   8
   9 #ifndef ROUTING_H
  10 #define ROUTING_H
  11
  12 #include <stdio.h>
  13 #include <stdint.h>
  14 #include <netinet/in.h>    /* for ntohs() */
  15 #include <arpa/inet.h>     /* for inet_ntop() */
  16
  17 #include "proto_struct.h"
  18 #include "dissector_eth.h"
  19
  20 struct routinghdr {
  21         uint8_t h_next_header;
  22         uint8_t h_hdr_ext_len;
  23         uint8_t h_routing_type;
  24         uint8_t h_segments_left;
  25 } __attribute__((packed));
  26
  27 static inline void routing(uint8_t *packet, size_t len)
  28 {
  29         uint8_t hdr_ext_len;
  30         struct routinghdr *routing = (struct routinghdr *) packet;
  31
  32         hdr_ext_len = (routing->h_hdr_ext_len + 1) * 8;
  33         if (len < hdr_ext_len || len < sizeof(struct routinghdr))
  34                 return;
  35
  36         tprintf("\t [ Routing ");
  37         tprintf("NextHdr (%u), ", routing->h_next_header);
  38         tprintf("HdrExtLen (%u), ", hdr_ext_len);
  39         tprintf("Type (%u), ", routing->h_routing_type);
  40         tprintf("Left (%u), ", routing->h_segments_left);
  41         if(routing->h_routing_type == 0) {
  42                 char address[INET6_ADDRSTRLEN];
  43                 for (int i = sizeof(struct routinghdr) + 4;
  44                      i < hdr_ext_len; i += 16) {
  45                         tprintf("\n\t   Address: ");
  46                         tprintf("%s", inet_ntop(AF_INET6, &packet[i],
  47                                 address, sizeof(address)));
  48                 }
  49         } else {
  50                 tprintf("Appendix 0x");
  51                 for (uint8_t i = sizeof(struct routinghdr);
  52                      i < hdr_ext_len; i++)
  53                         tprintf("%02x",(uint8_t) packet[i]);
  54         }
  55         tprintf(" ]\n");
  56 }
  57
  58 static inline void routing_less(uint8_t *packet, size_t len)
  59 {
  60         uint8_t hdr_ext_len;
  61         struct routinghdr *routing = (struct routinghdr *) packet;
  62
  63         hdr_ext_len = (routing->h_hdr_ext_len + 1) * 8;
  64         if (len < hdr_ext_len || len < sizeof(struct routinghdr))
  65                 return;
  66
  67         tprintf(" Routing Type %u", routing->h_routing_type);
  68 }
  69
  70 static inline void routing_next(uint8_t *packet, size_t len,
  71                              struct hash_table **table,
  72                              unsigned int *key, size_t *off)
  73 {
  74         uint8_t hdr_ext_len;
  75         struct routinghdr *routing = (struct routinghdr *) packet;
  76
  77         hdr_ext_len = (routing->h_hdr_ext_len + 1) * 8;
  78         if (len < hdr_ext_len || len < sizeof(struct routinghdr))
  79                 return;
  80
  81         (*off) = hdr_ext_len;
  82         (*key) = routing->h_next_header;
  83         (*table) = &eth_lay3;
  84 }
  85
  86 struct protocol ipv6_routing_ops = {
  87         .key = 0x2B,
  88         .print_full = routing,
  89         .print_less = routing_less,
  90         .print_pay_ascii = empty,
  91         .print_pay_hex = empty,
  92         .print_pay_none = routing,
  93         .print_all_hex = hex,
  94         .proto_next = routing_next,
  95 };
  96
  97 #endif /* ROUTING_H */