path: root/sbin/dhclient/dhcpd.h

/*	$OpenBSD: dhcpd.h,v 1.5 2004/02/10 13:12:48 henning Exp $	*/

/* Definitions for dhcpd... */

/*
 * 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 <netinet/in.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <ctype.h>
#include <time.h>

#include "osdep.h"
#include "dhcp.h"
#include "tree.h"
#include "hash.h"
#include "inet.h"

struct option_data {
	int len;
	u_int8_t *data;
};

struct string_list {
	struct string_list *next;
	char *string;
};

/* A name server, from /etc/resolv.conf. */
struct name_server {
	struct name_server *next;
	struct sockaddr_in addr;
	TIME rcdate;
};

/* A domain search list element. */
struct domain_search_list {
	struct domain_search_list *next;
	char *domain;
	TIME rcdate;
};

/* A dhcp packet and the pointers to its option values. */
struct packet {
	struct dhcp_packet *raw;
	int packet_length;
	int packet_type;
	int options_valid;
	int client_port;
	struct iaddr client_addr;
	struct interface_info *interface;	/* Interface on which packet
						   was received. */
	struct hardware *haddr;		/* Physical link address
					   of local sender (maybe gateway). */
	struct shared_network *shared_network;
	struct option_data options[256];
	int got_requested_address;	/* True if client sent the
					   dhcp-requested-address option. */
};

struct hardware {
	u_int8_t htype;
	u_int8_t hlen;
	u_int8_t haddr[16];
};

/* A dhcp lease declaration structure. */
struct lease {
	struct lease *next;
	struct lease *prev;
	struct lease *n_uid, *n_hw;
	struct lease *waitq_next;

	struct iaddr ip_addr;
	TIME starts, ends, timestamp;
	unsigned char *uid;
	int uid_len;
	int uid_max;
	unsigned char uid_buf[32];
	char *hostname;
	char *client_hostname;
	struct host_decl *host;
	struct subnet *subnet;
	struct shared_network *shared_network;
	struct hardware hardware_addr;

	int flags;
#       define STATIC_LEASE		1
#       define BOOTP_LEASE		2
#	define DYNAMIC_BOOTP_OK		4
#	define PERSISTENT_FLAGS		(DYNAMIC_BOOTP_OK)
#	define EPHEMERAL_FLAGS		(BOOTP_LEASE)
#	define MS_NULL_TERMINATION	8
#	define ABANDONED_LEASE		16

	struct lease_state *state;
	u_int8_t releasing;
};

struct lease_state {
	struct lease_state *next;

	struct interface_info *ip;

	TIME offered_expiry;

	struct tree_cache *options[256];
	u_int32_t expiry, renewal, rebind;
	char filename[DHCP_FILE_LEN];
	char *server_name;

	struct iaddr from;

	int max_message_size;
	u_int8_t *prl;
	int prl_len;
	int got_requested_address;	/* True if client sent the
					   dhcp-requested-address option. */
	int got_server_identifier;	/* True if client sent the
					   dhcp-server-identifier option. */
	struct shared_network *shared_network;	/* Shared network of interface
						   on which request arrived. */

	u_int32_t xid;
	u_int16_t secs;
	u_int16_t bootp_flags;
	struct in_addr ciaddr;
	struct in_addr giaddr;
	u_int8_t hops;
	u_int8_t offer;
};

#define ROOT_GROUP	0
#define HOST_DECL	1
#define SHARED_NET_DECL	2
#define SUBNET_DECL	3
#define CLASS_DECL	4
#define GROUP_DECL	5

/* Possible modes in which discover_interfaces can run. */

#define DISCOVER_RUNNING	0
#define DISCOVER_SERVER		1
#define DISCOVER_UNCONFIGURED	2
#define DISCOVER_RELAY		3
#define DISCOVER_REQUESTED	4

/* Group of declarations that share common parameters. */
struct group {
	struct group *next;

	struct subnet *subnet;
	struct shared_network *shared_network;

	TIME default_lease_time;
	TIME max_lease_time;
	TIME bootp_lease_cutoff;
	TIME bootp_lease_length;

	char *filename;
	char *server_name;
	struct iaddr next_server;

	int boot_unknown_clients;
	int dynamic_bootp;
	int allow_bootp;
	int allow_booting;
	int one_lease_per_client;
	int get_lease_hostnames;
	int use_host_decl_names;
	int use_lease_addr_for_default_route;
	int authoritative;
	int always_reply_rfc1048;

	struct tree_cache *options[256];
};

/* A dhcp host declaration structure. */
struct host_decl {
	struct host_decl *n_ipaddr;
	char *name;
	struct hardware interface;
	struct tree_cache *fixed_addr;
	struct group *group;
};

struct shared_network {
	struct shared_network *next;
	char *name;
	struct subnet *subnets;
	struct interface_info *interface;
	struct lease *leases;
	struct lease *insertion_point;
	struct lease *last_lease;

	struct group *group;
};

struct subnet {
	struct subnet *next_subnet;
	struct subnet *next_sibling;
	struct shared_network *shared_network;
	struct interface_info *interface;
	struct iaddr interface_address;
	struct iaddr net;
	struct iaddr netmask;

	struct group *group;
};

struct class {
	char *name;

	struct group *group;
};

/* DHCP client lease structure... */
struct client_lease {
	struct client_lease *next;		      /* Next lease in list. */
	TIME expiry, renewal, rebind;			  /* Lease timeouts. */
	struct iaddr address;			    /* Address being leased. */
	char *server_name;			     /* Name of boot server. */
	char *filename;		     /* Name of file we're supposed to boot. */
	struct string_list *medium;			  /* Network medium. */

	unsigned int is_static : 1;    /* If set, lease is from config file. */
	unsigned int is_bootp : 1;  /* If set, lease was aquired with BOOTP. */

	struct option_data options[256];     /* Options supplied with lease. */
};

/* 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
};

/* Configuration information from the config file... */
struct client_config {
	struct option_data defaults[256]; /* Default values for options. */
	enum {
		ACTION_DEFAULT,		/* Use server value if present,
					   otherwise default. */
		ACTION_SUPERSEDE,	/* Always use default. */
		ACTION_PREPEND,		/* Prepend default to server. */
		ACTION_APPEND		/* Append default to server. */
	} default_actions[256];

	struct option_data send_options[256]; /* Send these to server. */
	u_int8_t required_options[256]; /* Options server must supply. */
	u_int8_t requested_options[256]; /* Options to request from server. */
	int requested_option_count;	/* Number of requested options. */
	TIME timeout;			/* Start to panic if we don't get a
					   lease in this time period when
					   SELECTING. */
	TIME initial_interval;		/* All exponential backoff intervals
					   start here. */
	TIME retry_interval;		/* If the protocol failed to produce
					   an address before the timeout,
					   try the protocol again after this
					   many seconds. */
	TIME select_interval;		/* Wait this many seconds from the
					   first DHCPDISCOVER before
					   picking an offered lease. */
	TIME reboot_timeout;		/* When in INIT-REBOOT, wait this
					   long before giving up and going
					   to INIT. */
	TIME backoff_cutoff;		/* When doing exponential backoff,
					   never back off to an interval
					   longer than this amount. */
	struct string_list *media;	/* Possible network media values. */
	char *script_name;		/* Name of config script. */
	enum { IGNORE, ACCEPT, PREFER } bootp_policy;
					/* Ignore, accept or prefer BOOTP
					   responses. */
	struct string_list *medium;	/* Current network medium. */

	struct iaddrlist *reject_list;	/* Servers to reject. */
};

/* Per-interface state used in the dhcp client... */
struct client_state {
	struct client_lease *active;		  /* Currently active lease. */
	struct client_lease *new;			       /* New lease. */
	struct client_lease *offered_leases;	    /* Leases offered to us. */
	struct client_lease *leases;		/* Leases we currently hold. */
	struct client_lease *alias;			     /* Alias lease. */

	enum dhcp_state state;		/* Current state for this interface. */
	struct iaddr destination;		    /* Where to send packet. */
	u_int32_t xid;					  /* Transaction ID. */
	u_int16_t secs;			    /* secs value from DHCPDISCOVER. */
	TIME first_sending;			/* When was first copy sent? */
	TIME interval;		      /* What's the current resend interval? */
	struct string_list *medium;		   /* Last media type tried. */

	struct dhcp_packet packet;		    /* Outgoing DHCP packet. */
	int packet_length;	       /* Actual length of generated packet. */

	struct iaddr requested_address;	    /* Address we would like to get. */

	struct client_config *config;	    /* Information from config file. */

	char **scriptEnv;  /* Client script env */
	int scriptEnvsize; /* size of the env table */

	struct string_list *env;	       /* Client script environment. */
	int envc;			/* Number of entries in environment. */
};

/* Information about each network interface. */

struct interface_info {
	struct interface_info *next;	/* Next interface in list... */
	struct shared_network *shared_network;
				/* Networks connected to this interface. */
	struct hardware hw_address;	/* Its physical address. */
	struct in_addr primary_address;	/* Primary interface address. */
	char name[IFNAMSIZ];		/* Its name... */
	int rfdesc;			/* Its read file descriptor. */
	int wfdesc;			/* Its write file descriptor, if
					   different. */
	unsigned char *rbuf;		/* Read buffer, if required. */
	size_t rbuf_max;		/* Size of read buffer. */
	size_t rbuf_offset;		/* Current offset into buffer. */
	size_t rbuf_len;		/* Length of data in buffer. */

	struct ifreq *ifp;		/* Pointer to ifreq struct. */
	u_int32_t flags;		/* Control flags... */
#define INTERFACE_REQUESTED 1
#define INTERFACE_AUTOMATIC 2

	/* Only used by DHCP client code. */
	struct client_state *client;
	int noifmedia;
	int errors;
	int dead;
	u_int16_t index;
};

struct hardware_link {
	struct hardware_link *next;
	char name[IFNAMSIZ];
	struct hardware address;
};

struct timeout {
	struct timeout *next;
	TIME when;
	void (*func)(void *);
	void *what;
};

struct protocol {
	struct protocol *next;
	int fd;
	void (*handler)(struct protocol *);
	void *local;
};

/* Bitmask of dhcp option codes. */
typedef unsigned char option_mask[16];

/* DHCP Option mask manipulation macros... */
#define OPTION_ZERO(mask)	(memset(mask, 0, 16))
#define OPTION_SET(mask, bit)	(mask[bit >> 8] |= (1 << (bit & 7)))
#define OPTION_CLR(mask, bit)	(mask[bit >> 8] &= ~(1 << (bit & 7)))
#define OPTION_ISSET(mask, bit)	(mask[bit >> 8] & (1 << (bit & 7)))
#define OPTION_ISCLR(mask, bit)	(!OPTION_ISSET(mask, bit))

/* An option occupies its length plus two header bytes (code and
    length) for every 255 bytes that must be stored. */
#define OPTION_SPACE(x)		((x) + 2 * ((x) / 255 + 1))

/* Default path to dhcpd config file. */
#define _PATH_DHCLIENT_CONF	"/etc/dhclient.conf"
#define _PATH_DHCLIENT_PID	"/var/run/dhclient.pid"
#define _PATH_DHCLIENT_DB	"/var/db/dhclient.leases"
#define _PATH_RESOLV_CONF	"/etc/resolv.conf"
#define _PATH_DHCRELAY_PID	"/var/run/dhcrelay.pid"
#define _PATH_DHCLIENT_PID	"/var/run/dhclient.pid"
#define _PATH_DHCLIENT_DB	"/var/db/dhclient.leases"
#define DHCPD_LOG_FACILITY	LOG_DAEMON

#define MAX_TIME 0x7fffffff
#define MIN_TIME 0

/* External definitions... */

/* options.c */

void parse_options(struct packet *);
void parse_option_buffer(struct packet *, unsigned char *, int);
int cons_options(struct packet *, struct dhcp_packet *, int,
    struct tree_cache **, int, int, int, u_int8_t *, int);
int store_options(unsigned char *, int, struct tree_cache **,
    unsigned char *, int, int, int, int);
char *pretty_print_option(unsigned int,
    unsigned char *, int, int, int);
void do_packet(struct interface_info *, struct dhcp_packet *,
    int, unsigned int, struct iaddr, struct hardware *);

/* errwarn.c */
extern int warnings_occurred;
void error(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
int warn(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
int note(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
int debug(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
int parse_warn(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));

/* dhcpd.c */
extern TIME cur_time;
extern struct group root_group;

extern u_int16_t local_port;
extern u_int16_t remote_port;
extern int log_priority;
extern int log_perror;

int main(int, char **);
void cleanup(void);

/* conflex.c */
extern int lexline, lexchar;
extern char *token_line, *tlname;
extern char comments[4096];
extern int comment_index;
extern int eol_token;
void new_parse(char *);
int next_token(char **, FILE *);
int peek_token(char **, FILE *);

/* confpars.c */
int readconf(void);
void read_leases(void);
int parse_statement(FILE *, struct group *, int, struct host_decl *, int);
void parse_allow_deny(FILE *, struct group *, int);
void skip_to_semi(FILE *);
int parse_boolean(FILE *);
int parse_semi(FILE *);
int parse_lbrace(FILE *);
void parse_host_declaration(FILE *, struct group *);
char *parse_host_name(FILE *);
void parse_class_declaration(FILE *, struct group *, int);
void parse_lease_time(FILE *, TIME *);
void parse_shared_net_declaration(FILE *, struct group *);
void parse_subnet_declaration(FILE *, struct shared_network *);
void parse_group_declaration(FILE *, struct group *);
void parse_hardware_param(FILE *, struct hardware *);
char *parse_string(FILE *);
struct tree *parse_ip_addr_or_hostname(FILE *, int);
struct tree_cache *parse_fixed_addr_param(FILE *);
void parse_option_param(FILE *, struct group *);
TIME parse_timestamp(FILE *);
struct lease *parse_lease_declaration(FILE *);
void parse_address_range(FILE *, struct subnet *);
TIME parse_date(FILE *);
unsigned char *parse_numeric_aggregate(FILE *, unsigned char *, int *,
    int, int, int);
void convert_num(unsigned char *, char *, int, int);

/* tree.c */
pair cons(caddr_t, pair);
struct tree_cache *tree_cache(struct tree *);
struct tree *tree_host_lookup(char *);
struct dns_host_entry *enter_dns_host(char *);
struct tree *tree_const(unsigned char *, int);
struct tree *tree_concat(struct tree *, struct tree *);
struct tree *tree_limit(struct tree *, int);
int tree_evaluate(struct tree_cache *);

/* dhcp.c */
extern int outstanding_pings;

void dhcp(struct packet *);
void dhcpdiscover(struct packet *);
void dhcprequest(struct packet *);
void dhcprelease(struct packet *);
void dhcpdecline(struct packet *);
void dhcpinform(struct packet *);
void nak_lease(struct packet *, struct iaddr *cip);
void ack_lease(struct packet *, struct lease *, unsigned int, TIME);
void dhcp_reply(struct lease *);
struct lease *find_lease(struct packet *, struct shared_network *, int *);
struct lease *mockup_lease(struct packet *, struct shared_network *,
    struct host_decl *);

/* bootp.c */
void bootp(struct packet *);

/* memory.c */
void enter_host(struct host_decl *);
struct host_decl *find_hosts_by_haddr(int, unsigned char *, int);
struct host_decl *find_hosts_by_uid(unsigned char *, int);
struct subnet *find_host_for_network(struct host_decl **, struct iaddr *,
    struct shared_network *);
void new_address_range(struct iaddr, struct iaddr, struct subnet *, int);
extern struct subnet *find_grouped_subnet(struct shared_network *,
    struct iaddr);
extern struct subnet *find_subnet(struct iaddr);
void enter_shared_network(struct shared_network *);
int subnet_inner_than(struct subnet *, struct subnet *, int);
void enter_subnet(struct subnet *);
void enter_lease(struct lease *);
int supersede_lease(struct lease *, struct lease *, int);
void release_lease(struct lease *);
void abandon_lease(struct lease *, char *);
struct lease *find_lease_by_uid(unsigned char *, int);
struct lease *find_lease_by_hw_addr(unsigned char *, int);
struct lease *find_lease_by_ip_addr(struct iaddr);
void uid_hash_add(struct lease *);
void uid_hash_delete(struct lease *);
void hw_hash_add(struct lease *);
void hw_hash_delete(struct lease *);
struct class *add_class(int, char *);
struct class *find_class(int, unsigned char *, int);
struct group *clone_group(struct group *, char *);
void write_leases(void);
void dump_subnets(void);

/* alloc.c */
VOIDPTR dmalloc(int, char *);
void dfree(VOIDPTR, char *);
struct packet *new_packet(char *);
struct dhcp_packet *new_dhcp_packet(char *);
struct tree *new_tree(char *);
struct tree_cache *new_tree_cache(char *);
struct hash_table *new_hash_table(int, char *);
struct hash_bucket *new_hash_bucket(char *);
struct lease *new_lease(char *);
struct lease *new_leases(int, char *);
struct subnet *new_subnet(char *);
struct class *new_class(char *);
struct shared_network *new_shared_network(char *);
struct group *new_group(char *);
struct protocol *new_protocol(char *);
struct lease_state *new_lease_state(char *);
struct domain_search_list *new_domain_search_list(char *);
struct name_server *new_name_server(char *);
struct string_list *new_string_list(size_t size, char * name);
void free_name_server(struct name_server *, char *);
void free_domain_search_list(struct domain_search_list *, char *);
void free_lease_state(struct lease_state *, char *);
void free_protocol(struct protocol *, char *);
void free_group(struct group *, char *);
void free_shared_network(struct shared_network *, char *);
void free_class(struct class *, char *);
void free_subnet(struct subnet *, char *);
void free_lease(struct lease *, char *);
void free_hash_bucket(struct hash_bucket *, char *);
void free_hash_table(struct hash_table *, char *);
void free_tree_cache(struct tree_cache *, char *);
void free_packet(struct packet *, char *);
void free_dhcp_packet(struct dhcp_packet *, char *);
void free_tree(struct tree *, char *);
void free_string_list(struct string_list *, char *);

/* print.c */
char *print_hw_addr(int, int, unsigned char *);
void print_lease(struct lease *);
void dump_raw(unsigned char *, int);
void dump_packet(struct packet *);
void hash_dump(struct hash_table *);

/* socket.c */
#if defined(USE_SOCKET_SEND) || defined(USE_SOCKET_RECEIVE) \
	|| defined(USE_SOCKET_FALLBACK)
int if_register_socket(struct interface_info *);
#endif

#if defined(USE_SOCKET_FALLBACK) && !defined(USE_SOCKET_SEND)
void if_reinitialize_fallback(struct interface_info *);
void if_register_fallback(struct interface_info *);
ssize_t send_fallback(struct interface_info *,
    struct packet *, struct dhcp_packet *, size_t, struct in_addr,
    struct sockaddr_in *, struct hardware *);
#endif

#ifdef USE_SOCKET_SEND
void if_reinitialize_send(struct interface_info *);
void if_register_send(struct interface_info *);
ssize_t send_packet(struct interface_info *,
    struct packet *, struct dhcp_packet *, size_t, struct in_addr,
    struct sockaddr_in *, struct hardware *);
#endif
#ifdef USE_SOCKET_FALLBACK
void fallback_discard(struct protocol *);
#endif
#ifdef USE_SOCKET_RECEIVE
void if_reinitialize_receive(struct interface_info *);
void if_register_receive(struct interface_info *);
ssize_t receive_packet(struct interface_info *, unsigned char *, size_t,
    struct sockaddr_in *, struct hardware *);
#endif
#ifdef USE_SOCKET_SEND
int can_unicast_without_arp(void);
int can_receive_unicast_unconfigured(struct interface_info *);
void maybe_setup_fallback(void);
#endif

/* bpf.c */
#if defined(USE_BPF_SEND) || defined(USE_BPF_RECEIVE)
int if_register_bpf(struct interface_info *);
#endif
#ifdef USE_BPF_SEND
void if_reinitialize_send(struct interface_info *);
void if_register_send(struct interface_info *);
ssize_t send_packet(struct interface_info *,
    struct packet *, struct dhcp_packet *, size_t, struct in_addr,
    struct sockaddr_in *, struct hardware *);
#endif
#ifdef USE_BPF_RECEIVE
void if_reinitialize_receive(struct interface_info *);
void if_register_receive(struct interface_info *);
ssize_t receive_packet(struct interface_info *, unsigned char *, size_t,
    struct sockaddr_in *, struct hardware *);
#endif
#ifdef USE_BPF_SEND
int can_unicast_without_arp(void);
int can_receive_unicast_unconfigured(struct interface_info *);
void maybe_setup_fallback(void);
#endif

/* raw.c */
#ifdef USE_RAW_SEND
void if_reinitialize_send(struct interface_info *);
void if_register_send(struct interface_info *);
ssize_t send_packet(struct interface_info *,
    struct packet *, struct dhcp_packet *, size_t, struct in_addr,
    struct sockaddr_in *, struct hardware *);
int can_unicast_without_arp(void);
int can_receive_unicast_unconfigured(struct interface_info *);
void maybe_setup_fallback(void);
#endif

/* dispatch.c */
extern struct interface_info *interfaces,
    *dummy_interfaces, *fallback_interface;
extern struct protocol *protocols;
extern int quiet_interface_discovery;
extern void (*bootp_packet_handler)(struct interface_info *,
    struct dhcp_packet *, int, unsigned int, struct iaddr, struct hardware *);
extern struct timeout *timeouts;
void discover_interfaces(int);
struct interface_info *setup_fallback(void);
void reinitialize_interfaces(void);
void dispatch(void);
int locate_network(struct packet *);
void got_one(struct protocol *);
void add_timeout(TIME, void (*)(void *), void *);
void cancel_timeout(void (*)(void *), void *);
void add_protocol(char *, int, void (*)(struct protocol *), void *);
void remove_protocol(struct protocol *);
int interface_link_status(char *);

/* hash.c */
struct hash_table *new_hash(void);
void add_hash(struct hash_table *, unsigned char *, int, unsigned char *);
void delete_hash_entry(struct hash_table *, unsigned char *, int);
unsigned char *hash_lookup(struct hash_table *, unsigned char *, int);

/* tables.c */
extern struct option dhcp_options[256];
extern unsigned char dhcp_option_default_priority_list[];
extern int sizeof_dhcp_option_default_priority_list;
extern char *hardware_types[256];
extern struct hash_table universe_hash;
extern struct universe dhcp_universe;
void initialize_universes(void);

/* 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);

/* inet.c */
struct iaddr subnet_number(struct iaddr, struct iaddr);
struct iaddr ip_addr(struct iaddr, struct iaddr, u_int32_t);
struct iaddr broadcast_addr(struct iaddr, struct iaddr);
u_int32_t host_addr(struct iaddr, struct iaddr);
int addr_eq(struct iaddr, struct iaddr);
char *piaddr(struct iaddr);

/* dhclient.c */
extern char *path_dhclient_conf;
extern char *path_dhclient_db;
extern char *path_dhclient_pid;
extern int interfaces_requested;

extern struct client_config top_level_config;

void dhcpoffer(struct packet *);
void dhcpack(struct packet *);
void dhcpnak(struct packet *);

void send_discover(void *);
void send_request(void *);
void send_release(void *);
void send_decline(void *);

void state_reboot(void *);
void state_init(void *);
void state_selecting(void *);
void state_requesting(void *);
void state_bound(void *);
void state_panic(void *);

void bind_lease(struct interface_info *);

void make_discover(struct interface_info *, struct client_lease *);
void make_request(struct interface_info *, struct client_lease *);
void make_decline(struct interface_info *, struct client_lease *);
void make_release(struct interface_info *, struct client_lease *);

void free_client_lease(struct client_lease *);
void rewrite_client_leases(void);
void write_client_lease(struct interface_info *, struct client_lease *, int);

void script_init(struct interface_info *, char *, struct string_list *);
void script_write_params(struct interface_info *,
    char *, struct client_lease *);
int script_go(struct interface_info *);
void client_envadd(struct client_state *,
    const char *, const char *, const char *, ...);
void script_set_env(struct client_state *, const char *, const char *,
    const char *);
void script_flush_env(struct client_state *);
int dhcp_option_ev_name(char *, size_t, struct option *);

struct client_lease *packet_to_lease(struct packet *);
void go_daemon(void);
void write_client_pid_file(void);
void client_location_changed(void);

/* db.c */
int write_lease(struct lease *);
int commit_leases(void);
void db_startup(void);
void new_lease_file(void);

/* packet.c */
u_int32_t checksum(unsigned char *, unsigned, u_int32_t);
u_int32_t wrapsum(u_int32_t);
void assemble_hw_header(struct interface_info *, unsigned char *,
    int *, struct hardware *);
void assemble_udp_ip_header(struct interface_info *, unsigned char *,
    int *, u_int32_t, u_int32_t, unsigned int, unsigned char *, int);
ssize_t decode_hw_header(struct interface_info *, unsigned char *,
    int, struct hardware *);
ssize_t decode_udp_ip_header(struct interface_info *, unsigned char *,
    int, struct sockaddr_in *, unsigned char *, int);

/* ethernet.c */
void assemble_ethernet_header(struct interface_info *, unsigned char *,
    int *, struct hardware *);
ssize_t decode_ethernet_header(struct interface_info *, unsigned char *,
    int, struct hardware *);

/* tr.c */
void assemble_tr_header(struct interface_info *, unsigned char *,
    int *, struct hardware *);
ssize_t decode_tr_header(struct interface_info *,
    unsigned char *, int, struct hardware *);

/* dhxpxlt.c */
void convert_statement(FILE *);
void convert_host_statement(FILE *, jrefproto);
void convert_host_name(FILE *, jrefproto);
void convert_class_statement(FILE *, jrefproto, int);
void convert_class_decl(FILE *, jrefproto);
void convert_lease_time(FILE *, jrefproto, char *);
void convert_shared_net_statement(FILE *, jrefproto);
void convert_subnet_statement(FILE *, jrefproto);
void convert_subnet_decl(FILE *, jrefproto);
void convert_host_decl(FILE *, jrefproto);
void convert_hardware_decl(FILE *, jrefproto);
void convert_hardware_addr(FILE *, jrefproto);
void convert_filename_decl(FILE *, jrefproto);
void convert_servername_decl(FILE *, jrefproto);
void convert_ip_addr_or_hostname(FILE *, jrefproto, int);
void convert_fixed_addr_decl(FILE *, jrefproto);
void convert_option_decl(FILE *, jrefproto);
void convert_timestamp(FILE *, jrefproto);
void convert_lease_statement(FILE *, jrefproto);
void convert_address_range(FILE *, jrefproto);
void convert_date(FILE *, jrefproto, char *);
void convert_numeric_aggregate(FILE *, jrefproto, int, int, int, int);
void indent(int);

/* route.c */
void add_route_direct(struct interface_info *, struct in_addr);
void add_route_net(struct interface_info *, struct in_addr, struct in_addr);
void add_route_default_gateway(struct interface_info *, struct in_addr);
void remove_routes(struct in_addr);
void remove_if_route(struct interface_info *, struct in_addr);
void remove_all_if_routes(struct interface_info *);
void set_netmask(struct interface_info *, struct in_addr);
void set_broadcast_addr(struct interface_info *, struct in_addr);
void set_ip_address(struct interface_info *, struct in_addr);

/* clparse.c */
int read_client_conf(void);
void read_client_leases(void);
void parse_client_statement(FILE *, struct interface_info *,
    struct client_config *);
int parse_X(FILE *, u_int8_t *, int);
int parse_option_list(FILE *, u_int8_t *);
void parse_interface_declaration(FILE *, struct client_config *);
struct interface_info *interface_or_dummy(char *);
void make_client_state(struct interface_info *);
void make_client_config(struct interface_info *, struct client_config *);
void parse_client_lease_statement(FILE *, int);
void parse_client_lease_declaration(FILE *, struct client_lease *,
    struct interface_info **);
struct option *parse_option_decl(FILE *, struct option_data *);
void parse_string_list(FILE *, struct string_list **, int);
int parse_ip_addr(FILE *, struct iaddr *);
void parse_reject_statement(FILE *, struct client_config *);

/* dhcrelay.c */
void relay(struct interface_info *, struct dhcp_packet *, int,
    unsigned int, struct iaddr, struct hardware *);

/* icmp.c */
void icmp_startup(int, void (*)(struct iaddr, u_int8_t *, int));
int icmp_echorequest(struct iaddr *);
void icmp_echoreply(struct protocol *);

/* dns.c */
void dns_startup(void);
int ns_inaddr_lookup(u_int16_t, struct iaddr);
void dns_packet(struct protocol *);

/* resolv.c */
extern char path_resolv_conf[];
struct name_server *name_servers;
struct domain_search_list *domains;

void read_resolv_conf(TIME);
struct sockaddr_in *pick_name_server (void);