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/* vi: set sw=4 ts=4: */
/* dhcpd.h */
#ifndef _DHCPD_H
#define _DHCPD_H
/************************************/
/* Defaults _you_ may want to tweak */
/************************************/
/* the period of time the client is allowed to use that address */
#define LEASE_TIME (60*60*24*10) /* 10 days of seconds */
#define LEASES_FILE "/var/lib/misc/udhcpd.leases"
/* where to find the DHCP server configuration file */
#define DHCPD_CONF_FILE "/etc/udhcpd.conf"
/*****************************************************************/
/* Do not modify below here unless you know what you are doing!! */
/*****************************************************************/
/* DHCP protocol -- see RFC 2131 */
#define SERVER_PORT 67
#define CLIENT_PORT 68
#define DHCP_MAGIC 0x63825363
/* DHCP option codes (partial list) */
#define DHCP_PADDING 0x00
#define DHCP_SUBNET 0x01
#define DHCP_TIME_OFFSET 0x02
#define DHCP_ROUTER 0x03
#define DHCP_TIME_SERVER 0x04
#define DHCP_NAME_SERVER 0x05
#define DHCP_DNS_SERVER 0x06
#define DHCP_LOG_SERVER 0x07
#define DHCP_COOKIE_SERVER 0x08
#define DHCP_LPR_SERVER 0x09
#define DHCP_HOST_NAME 0x0c
#define DHCP_BOOT_SIZE 0x0d
#define DHCP_DOMAIN_NAME 0x0f
#define DHCP_SWAP_SERVER 0x10
#define DHCP_ROOT_PATH 0x11
#define DHCP_IP_TTL 0x17
#define DHCP_MTU 0x1a
#define DHCP_BROADCAST 0x1c
#define DHCP_NTP_SERVER 0x2a
#define DHCP_WINS_SERVER 0x2c
#define DHCP_REQUESTED_IP 0x32
#define DHCP_LEASE_TIME 0x33
#define DHCP_OPTION_OVER 0x34
#define DHCP_MESSAGE_TYPE 0x35
#define DHCP_SERVER_ID 0x36
#define DHCP_PARAM_REQ 0x37
#define DHCP_MESSAGE 0x38
#define DHCP_MAX_SIZE 0x39
#define DHCP_T1 0x3a
#define DHCP_T2 0x3b
#define DHCP_VENDOR 0x3c
#define DHCP_CLIENT_ID 0x3d
#define DHCP_FQDN 0x51
#define DHCP_END 0xFF
#define BOOTREQUEST 1
#define BOOTREPLY 2
#define ETH_10MB 1
#define ETH_10MB_LEN 6
#define DHCPDISCOVER 1
#define DHCPOFFER 2
#define DHCPREQUEST 3
#define DHCPDECLINE 4
#define DHCPACK 5
#define DHCPNAK 6
#define DHCPRELEASE 7
#define DHCPINFORM 8
#define BROADCAST_FLAG 0x8000
#define OPTION_FIELD 0
#define FILE_FIELD 1
#define SNAME_FIELD 2
/* miscellaneous defines */
#define MAC_BCAST_ADDR (uint8_t *) "\xff\xff\xff\xff\xff\xff"
#define OPT_CODE 0
#define OPT_LEN 1
#define OPT_DATA 2
struct option_set {
uint8_t *data;
struct option_set *next;
};
struct static_lease {
uint8_t *mac;
uint32_t *ip;
struct static_lease *next;
};
struct server_config_t {
uint32_t server; /* Our IP, in network order */
uint32_t start; /* Start address of leases, network order */
uint32_t end; /* End of leases, network order */
struct option_set *options; /* List of DHCP options loaded from the config file */
char *interface; /* The name of the interface to use */
int ifindex; /* Index number of the interface to use */
uint8_t arp[6]; /* Our arp address */
unsigned long lease; /* lease time in seconds (host order) */
unsigned long max_leases; /* maximum number of leases (including reserved address) */
char remaining; /* should the lease file be interpreted as lease time remaining, or
* as the time the lease expires */
unsigned long auto_time; /* how long should udhcpd wait before writing a config file.
* if this is zero, it will only write one on SIGUSR1 */
unsigned long decline_time; /* how long an address is reserved if a client returns a
* decline message */
unsigned long conflict_time; /* how long an arp conflict offender is leased for */
unsigned long offer_time; /* how long an offered address is reserved */
unsigned long min_lease; /* minimum lease a client can request*/
char *lease_file;
char *pidfile;
char *notify_file; /* What to run whenever leases are written */
uint32_t siaddr; /* next server bootp option */
char *sname; /* bootp server name */
char *boot_file; /* bootp boot file option */
struct static_lease *static_leases; /* List of ip/mac pairs to assign static leases */
};
extern struct server_config_t server_config;
extern struct dhcpOfferedAddr *leases;
/*** leases.h ***/
struct dhcpOfferedAddr {
uint8_t chaddr[16];
uint32_t yiaddr; /* network order */
uint32_t expires; /* host order */
};
extern uint8_t blank_chaddr[];
void clear_lease(uint8_t *chaddr, uint32_t yiaddr);
struct dhcpOfferedAddr *add_lease(uint8_t *chaddr, uint32_t yiaddr, unsigned long lease);
int lease_expired(struct dhcpOfferedAddr *lease);
struct dhcpOfferedAddr *oldest_expired_lease(void);
struct dhcpOfferedAddr *find_lease_by_chaddr(uint8_t *chaddr);
struct dhcpOfferedAddr *find_lease_by_yiaddr(uint32_t yiaddr);
uint32_t find_address(int check_expired);
/*** static_leases.h ***/
/* Config file will pass static lease info to this function which will add it
* to a data structure that can be searched later */
int addStaticLease(struct static_lease **lease_struct, uint8_t *mac, uint32_t *ip);
/* Check to see if a mac has an associated static lease */
uint32_t getIpByMac(struct static_lease *lease_struct, void *arg);
/* Check to see if an ip is reserved as a static ip */
uint32_t reservedIp(struct static_lease *lease_struct, uint32_t ip);
/* Print out static leases just to check what's going on (debug code) */
void printStaticLeases(struct static_lease **lease_struct);
/*** serverpacket.h ***/
int sendOffer(struct dhcpMessage *oldpacket);
int sendNAK(struct dhcpMessage *oldpacket);
int sendACK(struct dhcpMessage *oldpacket, uint32_t yiaddr);
int send_inform(struct dhcpMessage *oldpacket);
/*** files.h ***/
struct config_keyword {
const char *keyword;
int (* const handler)(const char *line, void *var);
void *var;
const char *def;
};
int read_config(const char *file);
void write_leases(void);
void read_leases(const char *file);
struct option_set *find_option(struct option_set *opt_list, char code);
#endif
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