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/* $OpenBSD: dhcpd.h,v 1.124 2013/11/19 15:12:23 mikeb Exp $ */
/*
* Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
* Copyright (c) 1995, 1996, 1997, 1998, 1999
* The Internet Software Consortium. 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.
* 3. Neither the name of The Internet Software Consortium nor the names
* of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM 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 INTERNET SOFTWARE CONSORTIUM 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.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <sys/queue.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <netdb.h>
#include <paths.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
#include "dhcp.h"
#define LOCAL_PORT 68
#define REMOTE_PORT 67
#define INTERNALSIG INT_MAX
#define DB_TIMEFMT "%w %Y/%m/%d %T UTC"
#define BAD_DB_TIMEFMT "%u %Y/%m/%d %T"
#define OLD_DB_TIMEFMT "%w %Y/%m/%d %T"
struct option {
char *name;
char *format;
};
struct option_data {
unsigned int len;
u_int8_t *data;
};
struct reject_elem {
struct reject_elem *next;
struct in_addr addr;
};
struct hardware {
u_int8_t htype;
u_int8_t hlen;
u_int8_t haddr[16];
};
struct client_lease {
TAILQ_ENTRY(client_lease) next;
time_t expiry, renewal, rebind;
struct in_addr address;
struct in_addr next_server;
char *server_name;
char *filename;
char *resolv_conf;
unsigned int is_static : 1;
unsigned int is_bootp : 1;
struct option_data options[256];
};
/* Possible states in which the client can be. */
enum dhcp_state {
S_REBOOTING,
S_INIT,
S_SELECTING,
S_REQUESTING,
S_BOUND,
S_RENEWING,
S_REBINDING
};
struct client_config {
struct option_data defaults[256];
enum {
ACTION_DEFAULT,
ACTION_SUPERSEDE,
ACTION_PREPEND,
ACTION_APPEND
} default_actions[256];
struct option_data send_options[256];
u_int8_t required_options[256];
u_int8_t requested_options[256];
u_int8_t ignored_options[256];
int requested_option_count;
int required_option_count;
int ignored_option_count;
time_t timeout;
time_t initial_interval;
time_t link_timeout;
time_t retry_interval;
time_t select_interval;
time_t reboot_timeout;
time_t backoff_cutoff;
enum { IGNORE, ACCEPT, PREFER }
bootp_policy;
struct reject_elem *reject_list;
char *resolv_tail;
};
struct client_state {
struct client_lease *active;
struct client_lease *new;
TAILQ_HEAD(, client_lease) offered_leases;
TAILQ_HEAD(, client_lease) leases;
enum dhcp_state state;
struct in_addr destination;
int flags;
#define IS_RESPONSIBLE 0x1
u_int32_t xid;
u_int16_t secs;
time_t first_sending;
time_t interval;
struct dhcp_packet packet;
struct dhcp_packet bootrequest_packet;
int bootrequest_packet_length;
struct in_addr requested_address;
};
struct interface_info {
struct hardware hw_address;
struct in_addr primary_address;
char name[IFNAMSIZ];
int rfdesc;
int wfdesc;
int ufdesc; /* unicast */
unsigned char *rbuf;
size_t rbuf_max;
size_t rbuf_offset;
size_t rbuf_len;
struct ifreq *ifp;
int noifmedia;
int errors;
u_int16_t index;
int linkstat;
int rdomain;
int flags;
#define IFI_NEW_LLADDR 0x00000001
#define IFI_HUP 0x00000002
};
struct dhcp_timeout {
time_t when;
void (*func)(void);
};
#define _PATH_DHCLIENT_CONF "/etc/dhclient.conf"
#define _PATH_DHCLIENT_DB "/var/db/dhclient.leases"
#define DHCPD_LOG_FACILITY LOG_DAEMON
/* External definitions. */
extern struct interface_info *ifi;
extern struct client_state *client;
extern struct client_config *config;
extern struct imsgbuf *unpriv_ibuf;
extern struct in_addr deleting;
extern struct in_addr adding;
extern struct in_addr active_addr;
extern volatile sig_atomic_t quit;
/* options.c */
int cons_options(struct option_data *);
char *pretty_print_option(unsigned int, struct option_data *, int);
void do_packet(unsigned int, struct in_addr, struct hardware *);
/* errwarn.c */
extern int warnings_occurred;
void error(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
int warning(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
int note(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
#ifdef DEBUG
int debug(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
#endif
int parse_warn(char *);
/* conflex.c */
extern int lexline, lexchar;
extern char *token_line, *tlname;
void new_parse(char *);
int next_token(char **, FILE *);
int peek_token(char **, FILE *);
/* parse.c */
void skip_to_semi(FILE *);
int parse_semi(FILE *);
char *parse_string(FILE *);
int parse_ip_addr(FILE *, struct in_addr *);
void parse_hardware_param(FILE *, struct hardware *);
void parse_lease_time(FILE *, time_t *);
void convert_num(unsigned char *, char *, int, int);
time_t parse_date(FILE *);
/* bpf.c */
void if_register_send(void);
void if_register_receive(void);
ssize_t send_packet(struct in_addr, struct sockaddr_in *, struct hardware *);
ssize_t receive_packet(struct sockaddr_in *, struct hardware *);
/* dispatch.c */
void discover_interface(void);
void dispatch(void);
void set_timeout(time_t, void (*)(void));
void set_timeout_interval(time_t, void (*)(void));
void cancel_timeout(void);
void interface_link_forceup(char *);
int interface_status(char *);
int get_rdomain(char *);
int subnet_exists(struct client_lease *);
/* tables.c */
extern const struct option dhcp_options[256];
/* convert.c */
u_int32_t getULong(unsigned char *);
int32_t getLong(unsigned char *);
u_int16_t getUShort(unsigned char *);
int16_t getShort(unsigned char *);
void putULong(unsigned char *, u_int32_t);
void putLong(unsigned char *, int32_t);
void putUShort(unsigned char *, unsigned int);
void putShort(unsigned char *, int);
/* dhclient.c */
extern char *path_dhclient_conf;
extern char *path_dhclient_db;
extern int log_perror;
extern int routefd;
void dhcpoffer(struct in_addr, struct option_data *, char *);
void dhcpack(struct in_addr, struct option_data *, char *);
void dhcpnak(struct in_addr, struct option_data *, char *);
void free_client_lease(struct client_lease *);
void routehandler(void);
/* packet.c */
void assemble_hw_header(unsigned char *, int *, struct hardware *);
void assemble_udp_ip_header(unsigned char *, int *, u_int32_t, u_int32_t,
unsigned int, unsigned char *, int);
ssize_t decode_hw_header(unsigned char *, int, struct hardware *);
ssize_t decode_udp_ip_header(unsigned char *, int, struct sockaddr_in *,
int);
/* clparse.c */
int read_client_conf(void);
void read_client_leases(void);
/* kroute.c */
void delete_addresses(char *, int);
void delete_address(char *, int, struct in_addr);
void add_address(char *, int, struct in_addr, struct in_addr);
void flush_routes(char *, int);
void add_route(int, struct in_addr, struct in_addr, struct in_addr, int, int);
void sendhup(struct client_lease *);
int resolv_conf_priority(int);
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