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/*
* dhcpcd - DHCP client daemon
* Copyright 2006-2008 Roy Marples <roy@marples.name>
* All rights reserved
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef DHCP_H
#define DHCP_H
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/udp.h>
#include <stdint.h>
#include "dhcpcd.h"
#include "interface.h"
/* Max MTU - defines dhcp option length */
#define MTU_MAX 1500
#define MTU_MIN 576
/* UDP port numbers for DHCP */
#define DHCP_SERVER_PORT 67
#define DHCP_CLIENT_PORT 68
#define MAGIC_COOKIE 0x63825363
#define BROADCAST_FLAG 0x8000
/* DHCP message OP code */
#define DHCP_BOOTREQUEST 1
#define DHCP_BOOTREPLY 2
/* DHCP message type */
#define DHCP_DISCOVER 1
#define DHCP_OFFER 2
#define DHCP_REQUEST 3
#define DHCP_DECLINE 4
#define DHCP_ACK 5
#define DHCP_NAK 6
#define DHCP_RELEASE 7
#define DHCP_INFORM 8
/* DHCP options */
enum DHCP_OPTIONS
{
DHCP_PAD = 0,
DHCP_NETMASK = 1,
DHCP_TIMEROFFSET = 2,
DHCP_ROUTERS = 3,
DHCP_TIMESERVER = 4,
DHCP_NAMESERVER = 5,
DHCP_DNSSERVER = 6,
DHCP_LOGSERVER = 7,
DHCP_COOKIESERVER = 8,
DHCP_HOSTNAME = 12,
DHCP_DNSDOMAIN = 15,
DHCP_ROOTPATH = 17,
DHCP_DEFAULTIPTTL = 23,
DHCP_MTU = 26,
DHCP_BROADCAST = 28,
DHCP_MASKDISCOVERY = 29,
DHCP_ROUTERDISCOVERY = 31,
DHCP_STATICROUTE = 33,
DHCP_NISDOMAIN = 40,
DHCP_NISSERVER = 41,
DHCP_NTPSERVER = 42,
DHCP_ADDRESS = 50,
DHCP_LEASETIME = 51,
DHCP_OPTIONSOVERLOADED = 52,
DHCP_MESSAGETYPE = 53,
DHCP_SERVERIDENTIFIER = 54,
DHCP_PARAMETERREQUESTLIST = 55,
DHCP_MESSAGE = 56,
DHCP_MAXMESSAGESIZE = 57,
DHCP_RENEWALTIME = 58,
DHCP_REBINDTIME = 59,
DHCP_CLASSID = 60,
DHCP_CLIENTID = 61,
DHCP_USERCLASS = 77, /* RFC 3004 */
DHCP_FQDN = 81,
DHCP_DNSSEARCH = 119, /* RFC 3397 */
DHCP_SIPSERVER = 120, /* RFC 3361 */
DHCP_CSR = 121, /* RFC 3442 */
DHCP_MSCSR = 249, /* MS code for RFC 3442 */
DHCP_END = 255
};
/* SetFQDNHostName values - lsnybble used in flags
* byte (see buildmsg.c), hsnybble to create order
* and to allow 0x00 to mean disable
*/
enum FQQN {
FQDN_DISABLE = 0x00,
FQDN_NONE = 0x18,
FQDN_PTR = 0x20,
FQDN_BOTH = 0x31
};
typedef struct fqdn_t
{
uint8_t flags;
uint8_t r1;
uint8_t r2;
char *name;
} fqdn_t;
typedef struct dhcp_t
{
char version[11];
struct in_addr serveraddress;
char serverhw[IF_NAMESIZE];
char servername[64];
struct in_addr address;
struct in_addr netmask;
struct in_addr broadcast;
unsigned short mtu;
uint32_t leasedfrom;
uint32_t leasetime;
uint32_t renewaltime;
uint32_t rebindtime;
struct route_head *routes;
char *hostname;
fqdn_t *fqdn;
struct address_head *dnsservers;
char *dnsdomain;
char *dnssearch;
struct address_head *ntpservers;
struct address_head *nisservers;
char *nisdomain;
char *sipservers;
char *message;
char *rootpath;
bool frominfo;
} dhcp_t;
/* Sizes for DHCP options */
#define DHCP_CHADDR_LEN 16
#define SERVERNAME_LEN 64
#define BOOTFILE_LEN 128
#define DHCP_UDP_LEN (20 + 8)
#define DHCP_BASE_LEN (4 + 4 + 2 + 2 + 4 + 4 + 4 + 4 + 4)
#define DHCP_RESERVE_LEN (4 + 4 + 4 + 4 + 2)
#define DHCP_FIXED_LEN (DHCP_BASE_LEN + DHCP_CHADDR_LEN + \
+ SERVERNAME_LEN + BOOTFILE_LEN)
#define DHCP_OPTION_LEN (MTU_MAX - DHCP_FIXED_LEN - DHCP_UDP_LEN \
- DHCP_RESERVE_LEN)
/* Some crappy DHCP servers require the BOOTP minimum length */
#define BOOTP_MESSAGE_LENTH_MIN 300
typedef struct dhcpmessage_t
{
unsigned char op; /* message type */
unsigned char hwtype; /* hardware address type */
unsigned char hwlen; /* hardware address length */
unsigned char hwopcount; /* should be zero in client message */
uint32_t xid; /* transaction id */
uint16_t secs; /* elapsed time in sec. from boot */
uint16_t flags;
uint32_t ciaddr; /* (previously allocated) client IP */
uint32_t yiaddr; /* 'your' client IP address */
uint32_t siaddr; /* should be zero in client's messages */
uint32_t giaddr; /* should be zero in client's messages */
unsigned char chaddr[DHCP_CHADDR_LEN]; /* client's hardware address */
unsigned char servername[SERVERNAME_LEN]; /* server host name */
unsigned char bootfile[BOOTFILE_LEN]; /* boot file name */
uint32_t cookie;
unsigned char options[DHCP_OPTION_LEN]; /* message options - cookie */
} dhcpmessage_t;
struct udp_dhcp_packet
{
struct ip ip;
struct udphdr udp;
dhcpmessage_t dhcp;
};
ssize_t send_message (const interface_t *iface, const dhcp_t *dhcp,
uint32_t xid, char type, const options_t *options);
void free_dhcp (dhcp_t *dhcp);
int parse_dhcpmessage (dhcp_t *dhcp, const dhcpmessage_t *message);
#endif
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