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/*
* dhcpcd - DHCP client daemon
* Copyright (c) 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 <arpa/inet.h>
#include <netinet/in.h>
#include <stdint.h>
#include "common.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
/* Constants taken from RFC 2131. */
#define T1 0.5
#define T2 0.875
#define DHCP_BASE 4
#define DHCP_MAX 64
#define DHCP_RAND_MIN -1
#define DHCP_RAND_MAX 1
#define DHCP_ARP_FAIL 10
/* number of usecs in a second. */
#define USECS_SECOND 1000000
/* As we use timevals, we should use the usec part for
* greater randomisation. */
#define DHCP_RAND_MIN_U DHCP_RAND_MIN * USECS_SECOND
#define DHCP_RAND_MAX_U DHCP_RAND_MAX * USECS_SECOND
#define PROBE_MIN_U PROBE_MIN * USECS_SECOND
#define PROBE_MAX_U PROBE_MAX * USECS_SECOND
/* DHCP options */
enum DHO {
DHO_PAD = 0,
DHO_SUBNETMASK = 1,
DHO_ROUTER = 3,
DHO_DNSSERVER = 6,
DHO_HOSTNAME = 12,
DHO_DNSDOMAIN = 15,
DHO_MTU = 26,
DHO_BROADCAST = 28,
DHO_STATICROUTE = 33,
DHO_NISDOMAIN = 40,
DHO_NISSERVER = 41,
DHO_NTPSERVER = 42,
DHO_VENDOR = 43,
DHO_IPADDRESS = 50,
DHO_LEASETIME = 51,
DHO_OPTIONSOVERLOADED = 52,
DHO_MESSAGETYPE = 53,
DHO_SERVERID = 54,
DHO_PARAMETERREQUESTLIST = 55,
DHO_MESSAGE = 56,
DHO_MAXMESSAGESIZE = 57,
DHO_RENEWALTIME = 58,
DHO_REBINDTIME = 59,
DHO_VENDORCLASSID = 60,
DHO_CLIENTID = 61,
DHO_USERCLASS = 77, /* RFC 3004 */
DHO_FQDN = 81,
DHO_DNSSEARCH = 119, /* RFC 3397 */
DHO_CSR = 121, /* RFC 3442 */
DHO_MSCSR = 249, /* MS code for RFC 3442 */
DHO_END = 255
};
/* FQDN values - lsnybble used in flags
* hsnybble to create order
* and to allow 0x00 to mean disable
*/
enum FQDN {
FQDN_DISABLE = 0x00,
FQDN_NONE = 0x18,
FQDN_PTR = 0x20,
FQDN_BOTH = 0x31
};
/* Sizes for DHCP options */
#define DHCP_CHADDR_LEN 16
#define SERVERNAME_LEN 64
#define BOOTFILE_LEN 128
#define DHCP_UDP_LEN (14 + 20 + 8)
#define DHCP_FIXED_LEN (DHCP_UDP_LEN + 226)
#define DHCP_OPTION_LEN (MTU_MAX - DHCP_FIXED_LEN)
/* Some crappy DHCP servers require the BOOTP minimum length */
#define BOOTP_MESSAGE_LENTH_MIN 300
struct dhcp_message {
uint8_t op; /* message type */
uint8_t hwtype; /* hardware address type */
uint8_t hwlen; /* hardware address length */
uint8_t 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 */
uint8_t chaddr[DHCP_CHADDR_LEN]; /* client's hardware address */
uint8_t servername[SERVERNAME_LEN]; /* server host name */
uint8_t bootfile[BOOTFILE_LEN]; /* boot file name */
uint32_t cookie;
uint8_t options[DHCP_OPTION_LEN]; /* message options - cookie */
} _packed;
struct dhcp_lease {
struct in_addr addr;
struct in_addr net;
struct in_addr brd;
uint32_t leasetime;
uint32_t renewaltime;
uint32_t rebindtime;
struct in_addr server;
time_t leasedfrom;
struct timeval boundtime;
uint8_t frominfo;
uint32_t cookie;
};
#include "dhcpcd.h"
#include "if-options.h"
#include "net.h"
#define add_option_mask(var, val) (var[val >> 3] |= 1 << (val & 7))
#define del_option_mask(var, val) (var[val >> 3] &= ~(1 << (val & 7)))
#define has_option_mask(var, val) (var[val >> 3] & (1 << (val & 7)))
int make_option_mask(uint8_t *, const char *, int);
void print_options(void);
char *get_option_string(const struct dhcp_message *, uint8_t);
int get_option_addr(struct in_addr *, const struct dhcp_message *, uint8_t);
int get_option_uint32(uint32_t *, const struct dhcp_message *, uint8_t);
int get_option_uint16(uint16_t *, const struct dhcp_message *, uint8_t);
int get_option_uint8(uint8_t *, const struct dhcp_message *, uint8_t);
#define is_bootp(m) (m && \
!IN_LINKLOCAL(htonl((m)->yiaddr)) && \
get_option_uint8(NULL, m, DHO_MESSAGETYPE) == -1)
struct rt *get_option_routes(const struct dhcp_message *, const char *, int *);
ssize_t configure_env(char **, const char *, const struct dhcp_message *,
const struct if_options *);
int dhcp_message_add_addr(struct dhcp_message *, uint8_t, struct in_addr);
ssize_t make_message(struct dhcp_message **, const struct interface *,
uint8_t);
int valid_dhcp_packet(unsigned char *);
ssize_t write_lease(const struct interface *, const struct dhcp_message *);
struct dhcp_message *read_lease(const struct interface *);
void get_lease(struct dhcp_lease *, const struct dhcp_message *);
#endif
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