proto_ip_esp.c

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * Copyright 2012 Markus Amend <markus@netsniff-ng.org>, Deutsche Flugsicherung GmbH
   4  * Subject to the GPL, version 2.
   5  *
   6  * Encapsulating Security Payload described in RFC4303
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdint.h>
  11 #include <netinet/in.h>    /* for ntohs() */
  12
  13 #include "proto.h"
  14 #include "built_in.h"
  15 #include "pkt_buff.h"
  16
  17 struct esp_hdr {
  18         uint32_t h_spi;
  19         uint32_t h_sn;
  20 } __packed;
  21
  22 static void esp(struct pkt_buff *pkt)
  23 {
  24         struct esp_hdr *esp_ops;
  25
  26         esp_ops = (struct esp_hdr *) pkt_pull(pkt, sizeof(*esp_ops));
  27         if (esp_ops == NULL)
  28                 return;
  29
  30         tprintf(" [ ESP ");
  31         tprintf("SPI (0x%x), ", ntohl(esp_ops->h_spi));
  32         tprintf("SN (0x%x)", ntohl(esp_ops->h_sn));
  33         tprintf(" ]\n");
  34 }
  35
  36 static void esp_less(struct pkt_buff *pkt)
  37 {
  38         struct esp_hdr *esp_ops;
  39
  40         esp_ops = (struct esp_hdr *) pkt_pull(pkt, sizeof(*esp_ops));
  41         if (esp_ops == NULL)
  42                 return;
  43
  44         tprintf(" ESP");
  45 }
  46
  47 struct protocol ip_esp_ops = {
  48         .key = 0x32,
  49         .print_full = esp,
  50         .print_less = esp_less,
  51 };