src/dhcpv4.h

   1 /**
   2  *   Copyright (C) 2012 Steven Barth <steven@midlink.org>
   3  *   Copyright (C) 2016 Hans Dedecker <dedeckeh@gmail.com>
   4  *
   5  *   This program is free software; you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License version 2
   7  *   as published by the Free Software Foundation.
   8  *
   9  *   This program is distributed in the hope that it will be useful,
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *   GNU General Public License version 2 for more details.
  13  *
  14  */
  15 #pragma once
  16
  17 #define DHCPV4_CLIENT_PORT 68
  18 #define DHCPV4_SERVER_PORT 67
  19
  20 #define DHCPV4_FLAG_BROADCAST  0x8000
  21
  22 #define DHCPV4_MIN_PACKET_SIZE 300
  23
  24 enum dhcpv4_op {
  25         DHCPV4_BOOTREQUEST = 1,
  26         DHCPV4_BOOTREPLY = 2
  27 };
  28
  29 enum dhcpv4_msg {
  30         DHCPV4_MSG_DISCOVER = 1,
  31         DHCPV4_MSG_OFFER = 2,
  32         DHCPV4_MSG_REQUEST = 3,
  33         DHCPV4_MSG_DECLINE = 4,
  34         DHCPV4_MSG_ACK = 5,
  35         DHCPV4_MSG_NAK = 6,
  36         DHCPV4_MSG_RELEASE = 7,
  37         DHCPV4_MSG_INFORM = 8,
  38         DHCPV4_MSG_FORCERENEW = 9,
  39 };
  40
  41 enum dhcpv4_opt {
  42         DHCPV4_OPT_PAD = 0,
  43         DHCPV4_OPT_NETMASK = 1,
  44         DHCPV4_OPT_ROUTER = 3,
  45         DHCPV4_OPT_DNSSERVER = 6,
  46         DHCPV4_OPT_DOMAIN = 15,
  47         DHCPV4_OPT_MTU = 26,
  48         DHCPV4_OPT_BROADCAST = 28,
  49         DHCPV4_OPT_NTPSERVER = 42,
  50         DHCPV4_OPT_LEASETIME = 51,
  51         DHCPV4_OPT_MESSAGE = 53,
  52         DHCPV4_OPT_SERVERID = 54,
  53         DHCPV4_OPT_RENEW = 58,
  54         DHCPV4_OPT_REBIND = 59,
  55         DHCPV4_OPT_IPADDRESS = 50,
  56         DHCPV4_OPT_HOSTNAME = 12,
  57         DHCPV4_OPT_REQUEST = 17,
  58         DHCPV4_OPT_USER_CLASS = 77,
  59         DHCPV4_OPT_AUTHENTICATION = 90,
  60         DHCPV4_OPT_SEARCH_DOMAIN = 119,
  61         DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE = 145,
  62         DHCPV4_OPT_END = 255,
  63 };
  64
  65 struct dhcpv4_message {
  66         uint8_t op;
  67         uint8_t htype;
  68         uint8_t hlen;
  69         uint8_t hops;
  70         uint32_t xid;
  71         uint16_t secs;
  72         uint16_t flags;
  73         struct in_addr ciaddr;
  74         struct in_addr yiaddr;
  75         struct in_addr siaddr;
  76         struct in_addr giaddr;
  77         uint8_t chaddr[16];
  78         char sname[64];
  79         char file[128];
  80         uint8_t options[312];
  81 };
  82
  83 struct dhcpv4_auth_forcerenew {
  84         uint8_t protocol;
  85         uint8_t algorithm;
  86         uint8_t rdm;
  87         uint32_t replay[2];
  88         uint8_t type;
  89         uint8_t key[16];
  90 } _packed;
  91
  92 struct dhcpv4_option {
  93         uint8_t type;
  94         uint8_t len;
  95         uint8_t data[];
  96 };
  97
  98
  99 #define dhcpv4_for_each_option(start, end, opt)\
 100         for (opt = (struct dhcpv4_option*)(start); \
 101                 &opt[1] <= (struct dhcpv4_option*)(end) && \
 102                         &opt->data[opt->len] <= (end); \
 103                 opt = (struct dhcpv4_option*)&opt->data[opt->len])