src/proto_ipv6.h

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * By Daniel Borkmann <daniel@netsniff-ng.org>
   4  * Copyright 2009, 2010 Daniel Borkmann.
   5  * Copyright 2010 Emmanuel Roullit.
   6  * Subject to the GPL, version 2.
   7  */
   8
   9 #ifndef IPV6_H
  10 #define IPV6_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 #include <asm/byteorder.h>
  17
  18 #include "csum.h"
  19 #include "proto_struct.h"
  20 #include "dissector_eth.h"
  21
  22 /*
  23  * IPv6 fixed header
  24  *
  25  * BEWARE, it is incorrect. The first 4 bits of flow_lbl
  26  * are glued to priority now, forming "class".
  27  */
  28 struct ipv6hdr {
  29 #if defined(__LITTLE_ENDIAN_BITFIELD)
  30         __extension__ uint8_t priority:4,
  31                               version:4;
  32 #elif defined(__BIG_ENDIAN_BITFIELD)
  33         __extension__ uint8_t version:4,
  34                               priority:4;
  35 #else
  36 # error "Please fix <asm/byteorder.h>"
  37 #endif
  38         uint8_t flow_lbl[3];
  39         uint16_t payload_len;
  40         uint8_t nexthdr;
  41         uint8_t hop_limit;
  42         struct in6_addr saddr;
  43         struct in6_addr daddr;
  44 } __attribute__((packed));
  45
  46 static inline void ipv6(uint8_t *packet, size_t len)
  47 {
  48         uint8_t traffic_class;
  49         uint32_t flow_label;
  50         char src_ip[INET6_ADDRSTRLEN];
  51         char dst_ip[INET6_ADDRSTRLEN];
  52         struct ipv6hdr *ip = (struct ipv6hdr *) packet;
  53
  54         if (len < sizeof(struct ipv6hdr))
  55                 return;
  56
  57         traffic_class = (ip->priority << 4) |
  58                         ((ip->flow_lbl[0] & 0xF0) >> 4);
  59         flow_label = ((ip->flow_lbl[0] & 0x0F) << 8) |
  60                      (ip->flow_lbl[1] << 4) | ip->flow_lbl[2];
  61
  62         inet_ntop(AF_INET6, &ip->saddr, src_ip, sizeof(src_ip));
  63         inet_ntop(AF_INET6, &ip->daddr, dst_ip, sizeof(dst_ip));
  64
  65         tprintf(" [ IPv6 ");
  66         tprintf("Addr (%s => %s), ", src_ip, dst_ip);
  67         tprintf("Version (%u), ", ip->version);
  68         tprintf("TrafficClass (%u), ", traffic_class);
  69         tprintf("FlowLabel (%u), ", flow_label);
  70         tprintf("Len (%u), ", ntohs(ip->payload_len));
  71         tprintf("NextHdr (%u), ", ip->nexthdr);
  72         tprintf("HopLimit (%u)", ip->hop_limit);
  73         tprintf(" ]\n");
  74 }
  75
  76 static inline void ipv6_less(uint8_t *packet, size_t len)
  77 {
  78         char src_ip[INET6_ADDRSTRLEN];
  79         char dst_ip[INET6_ADDRSTRLEN];
  80         struct ipv6hdr *ip = (struct ipv6hdr *) packet;
  81
  82         if (len < sizeof(struct ipv6hdr))
  83                 return;
  84
  85         inet_ntop(AF_INET6, &ip->saddr, src_ip, sizeof(src_ip));
  86         inet_ntop(AF_INET6, &ip->daddr, dst_ip, sizeof(dst_ip));
  87
  88         tprintf(" %s/%s Len %u", src_ip, dst_ip,
  89                 ntohs(ip->payload_len));
  90 }
  91
  92 static inline void ipv6_next(uint8_t *packet, size_t len,
  93                              struct hash_table **table,
  94                              unsigned int *key, size_t *off)
  95 {
  96         struct ipv6hdr *ip = (struct ipv6hdr *) packet;
  97
  98         if (len < sizeof(struct ipv6hdr))
  99                 goto invalid;
 100
 101         (*off) = sizeof(struct ipv6hdr);
 102         (*key) = ip->nexthdr;
 103         (*table) = &eth_lay3;
 104
 105         return;
 106 invalid:
 107         (*off) = 0;
 108         (*key) = 0;
 109         (*table) = NULL;
 110 }
 111
 112 struct protocol ipv6_ops = {
 113         .key = 0x86DD,
 114         .offset = sizeof(struct ipv6hdr),
 115         .print_full = ipv6,
 116         .print_less = ipv6_less,
 117         .print_pay_ascii = empty,
 118         .print_pay_hex = empty,
 119         .print_pay_none = ipv6,
 120         .print_all_cstyle = __hex2,
 121         .print_all_hex = __hex,
 122         .proto_next = ipv6_next,
 123 };
 124
 125 #endif /* IPV6_H */