/*
* dhcpcd - DHCP client daemon
* Copyright (c) 2006-2015 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 <limits.h>
#include <stdint.h>
#include "arp.h"
#include "auth.h"
#include "dhcp-common.h"
/* 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
#define DHCP_FORCERENEW 9
/* 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
#ifdef RFC2131_STRICT
/* Be strictly conformant for section 4.1.1 */
# define DHCP_MIN_DELAY 1
# define DHCP_MAX_DELAY 10
#else
/* or mirror the more modern IPv6RS and DHCPv6 delays */
# define DHCP_MIN_DELAY 0
# define DHCP_MAX_DELAY 1
#endif
/* 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_RAPIDCOMMIT = 80, /* RFC 4039 */
DHO_FQDN = 81,
DHO_AUTHENTICATION = 90, /* RFC 3118 */
DHO_AUTOCONFIGURE = 116, /* RFC 2563 */
DHO_DNSSEARCH = 119, /* RFC 3397 */
DHO_CSR = 121, /* RFC 3442 */
DHO_VIVCO = 124, /* RFC 3925 */
DHO_VIVSO = 125, /* RFC 3925 */
DHO_FORCERENEW_NONCE = 145, /* RFC 6704 */
DHO_SIXRD = 212, /* RFC 5969 */
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
/* Flags for the OPTIONSOVERLOADED field. */
#define OPTION_OVERLOADED_BOOT_FILE 1
#define OPTION_OVERLOADED_SERVER_NAME 2
/* Don't import common.h as that defines __unused which causes problems
* on some Linux systems which define it as part of a structure */
#if __GNUC__ > 2 || defined(__INTEL_COMPILER)
# ifndef __packed
# define __packed __attribute__((__packed__))
# endif
#else
# ifndef __packed
# define __packed
# endif
#endif
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_option_iterator {
const struct dhcp_message *message;
const uint8_t *ptr;
const uint8_t *end;
uint8_t extra_option_locations;
uint8_t extra_option_locations_set;
};
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;
uint8_t frominfo;
uint32_t cookie;
};
/* Extra data about servers stored in the lease file after the dhcp_message */
struct dhcp_server_info {
uint8_t gw_hwlen;
unsigned char gw_hwaddr[HWADDR_LEN];
};
enum DHS {
DHS_INIT,
DHS_DISCOVER,
DHS_REQUEST,
DHS_BOUND,
DHS_RENEW,
DHS_REBIND,
DHS_REBOOT,
DHS_INFORM,
DHS_RENEW_REQUESTED,
DHS_IPV4LL_BOUND,
DHS_PROBE
};
struct dhcp_state {
enum DHS state;
struct dhcp_message *sent;
struct dhcp_message *offer;
struct dhcp_message *new;
struct dhcp_message *old;
struct dhcp_lease lease;
const char *reason;
time_t interval;
time_t nakoff;
uint32_t xid;
int socket;
int raw_fd;
int arp_fd;
size_t buffer_size, buffer_len, buffer_pos;
unsigned char *buffer;
struct in_addr addr;
struct in_addr net;
struct in_addr dst;
uint8_t added;
char leasefile[PATH_MAX];
time_t start_uptime;
unsigned char *clientid;
struct authstate auth;
struct arp_statehead arp_states;
size_t arping_index;
struct arp_state *arp_ipv4ll;
unsigned int conflicts;
int nak_receive_count;
int failed_address_offer_count;
struct in_addr failed;
time_t defend;
char randomstate[128];
struct dhcp_server_info server_info;
};
#define D_STATE(ifp) \
((struct dhcp_state *)(ifp)->if_data[IF_DATA_DHCP])
#define D_CSTATE(ifp) \
((const struct dhcp_state *)(ifp)->if_data[IF_DATA_DHCP])
#define D_STATE_RUNNING(ifp) \
(D_CSTATE((ifp)) && D_CSTATE((ifp))->new && D_CSTATE((ifp))->reason)
#include "dhcpcd.h"
#include "if-options.h"
#ifdef INET
char *decode_rfc3361(const uint8_t *, size_t);
ssize_t decode_rfc3442(char *, size_t, const uint8_t *p, size_t);
ssize_t decode_rfc5969(char *, size_t, const uint8_t *p, size_t);
void dhcp_printoptions(const struct dhcpcd_ctx *,
const struct dhcp_opt *, size_t);
int get_option_addr(struct dhcpcd_ctx *,struct in_addr *,
const struct dhcp_message *, uint8_t);
#define IS_BOOTP(i, m) ((m) && \
!IN_LINKLOCAL(htonl((m)->yiaddr)) && \
get_option_uint8((i)->ctx, NULL, (m), DHO_MESSAGETYPE) == -1)
struct rt_head *get_option_routes(struct interface *,
const struct dhcp_message *);
ssize_t dhcp_env(char **, const char *, const struct dhcp_message *,
const struct interface *);
uint32_t dhcp_xid(const struct interface *);
struct dhcp_message *dhcp_message_new(const struct in_addr *addr,
const struct in_addr *mask);
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 *);
void dhcp_handleifa(int, struct interface *,
const struct in_addr *, const struct in_addr *, const struct in_addr *,
int);
void dhcp_drop(struct interface *, const char *);
void dhcp_start(struct interface *);
void dhcp_stop(struct interface *);
void dhcp_discover(void *);
void dhcp_inform(struct interface *);
void dhcp_bind(struct interface *, struct arp_state *);
void dhcp_reboot_newopts(struct interface *, unsigned long long);
void dhcp_close(struct interface *);
void dhcp_free(struct interface *);
int dhcp_dump(struct interface *);
#else
#define dhcp_drop(a, b) {}
#define dhcp_start(a) {}
#define dhcp_reboot(a, b) (b = b)
#define dhcp_reboot_newopts(a, b) (b = b)
#define dhcp_close(a) {}
#define dhcp_free(a) {}
#define dhcp_dump(a) (-1)
#endif
#endif