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/*
* OpenVPN -- An application to securely tunnel IP networks
* over a single TCP/UDP port, with support for SSL/TLS-based
* session authentication and key exchange,
* packet encryption, packet authentication, and
* packet compression.
*
* Copyright (C) 2002-2021 OpenVPN Inc <sales@openvpn.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef DHCP_H
#define DHCP_H
#include "common.h"
#include "buffer.h"
#include "proto.h"
#pragma pack(1)
/* DHCP Option types */
#define DHCP_PAD 0
#define DHCP_ROUTER 3
#define DHCP_MSG_TYPE 53 /* message type (u8) */
#define DHCP_END 255
/* DHCP Messages types */
#define DHCPDISCOVER 1
#define DHCPOFFER 2
#define DHCPREQUEST 3
#define DHCPDECLINE 4
#define DHCPACK 5
#define DHCPNAK 6
#define DHCPRELEASE 7
#define DHCPINFORM 8
/* DHCP UDP port numbers */
#define BOOTPS_PORT 67
#define BOOTPC_PORT 68
struct dhcp {
#define BOOTREQUEST 1
#define BOOTREPLY 2
uint8_t op; /* message op */
uint8_t htype; /* hardware address type (e.g. '1' = 10Mb Ethernet) */
uint8_t hlen; /* hardware address length (e.g. '6' for 10Mb Ethernet) */
uint8_t hops; /* client sets to 0, may be used by relay agents */
uint32_t xid; /* transaction ID, chosen by client */
uint16_t secs; /* seconds since request process began, set by client */
uint16_t flags;
uint32_t ciaddr; /* client IP address, client sets if known */
uint32_t yiaddr; /* 'your' IP address -- server's response to client */
uint32_t siaddr; /* server IP address */
uint32_t giaddr; /* relay agent IP address */
uint8_t chaddr[16]; /* client hardware address */
uint8_t sname[64]; /* optional server host name */
uint8_t file[128]; /* boot file name */
uint32_t magic; /* must be 0x63825363 (network order) */
};
struct dhcp_full {
struct openvpn_iphdr ip;
struct openvpn_udphdr udp;
struct dhcp dhcp;
#define DHCP_OPTIONS_BUFFER_SIZE 256
uint8_t options[DHCP_OPTIONS_BUFFER_SIZE];
};
#pragma pack()
in_addr_t dhcp_extract_router_msg(struct buffer *ipbuf);
#endif /* ifndef DHCP_H */
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