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/* vi: set sw=4 ts=4: */
/* dhcpd.h */
#ifndef UDHCP_DHCPD_H
#define UDHCP_DHCPD_H 1
PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
/************************************/
/* 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 CONFIG_DHCPD_LEASES_FILE
/* where to find the DHCP server configuration file */
#define DHCPD_CONF_FILE "/etc/udhcpd.conf"
struct option_set {
uint8_t *data;
struct option_set *next;
};
struct static_lease {
struct static_lease *next;
uint32_t nip;
uint8_t mac[6];
};
struct server_config_t {
char *interface; /* interface to use */
//TODO: ifindex, server_nip, server_mac
// are obtained from interface name.
// Instead of querying them *once*, create update_server_network_data_cache()
// and call it before any usage of these fields.
// update_server_network_data_cache() must re-query data
// if more than N seconds have passed after last use.
int ifindex;
uint32_t server_nip;
#if ENABLE_FEATURE_UDHCP_PORT
uint16_t port;
#endif
uint8_t server_mac[6]; /* our MAC address (used only for ARP probing) */
struct option_set *options; /* list of DHCP options loaded from the config file */
int verbose;
/* start,end are in host order: we need to compare start <= ip <= end */
uint32_t start_ip; /* start address of leases, in host order */
uint32_t end_ip; /* end of leases, in host order */
uint32_t max_lease_sec; /* maximum lease time (host order) */
uint32_t min_lease_sec; /* minimum lease time a client can request */
uint32_t max_leases; /* maximum number of leases (including reserved addresses) */
uint32_t auto_time; /* how long should udhcpd wait before writing a config file.
* if this is zero, it will only write one on SIGUSR1 */
uint32_t decline_time; /* how long an address is reserved if a client returns a
* decline message */
uint32_t conflict_time; /* how long an arp conflict offender is leased for */
uint32_t offer_time; /* how long an offered address is reserved */
uint32_t siaddr_nip; /* "next server" bootp option */
char *lease_file;
char *pidfile;
char *notify_file; /* what to run whenever leases are written */
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 */
};
#define server_config (*(struct server_config_t*)&bb_common_bufsiz1)
/* client_config sits in 2nd half of bb_common_bufsiz1 */
#if ENABLE_FEATURE_UDHCP_PORT
#define SERVER_PORT (server_config.port)
#else
#define SERVER_PORT 67
#endif
/*** leases.h ***/
typedef uint32_t leasetime_t;
typedef int32_t signed_leasetime_t;
struct dyn_lease {
/* "nip": IP in network order */
/* Unix time when lease expires. Kept in memory in host order.
* When written to file, converted to network order
* and adjusted (current time subtracted) */
leasetime_t expires;
uint32_t lease_nip;
/* We use lease_mac[6], since e.g. ARP probing uses
* only 6 first bytes anyway. We check received dhcp packets
* that their hlen == 6 and thus chaddr has only 6 significant bytes
* (dhcp packet has chaddr[16], not [6])
*/
uint8_t lease_mac[6];
uint8_t hostname[20];
uint8_t pad[2];
/* total size is a multiply of 4 */
} PACKED;
extern struct dyn_lease *g_leases;
struct dyn_lease *add_lease(
const uint8_t *chaddr, uint32_t yiaddr,
leasetime_t leasetime, uint8_t *hostname
) FAST_FUNC;
int is_expired_lease(struct dyn_lease *lease) FAST_FUNC;
struct dyn_lease *find_lease_by_mac(const uint8_t *mac) FAST_FUNC;
struct dyn_lease *find_lease_by_nip(uint32_t nip) FAST_FUNC;
uint32_t find_free_or_expired_nip(const uint8_t *safe_mac) FAST_FUNC;
/*** static_leases.h ***/
/* Config file parser will pass static lease info to this function
* which will add it to a data structure that can be searched later */
void add_static_lease(struct static_lease **st_lease_pp, uint8_t *mac, uint32_t nip) FAST_FUNC;
/* Find static lease IP by mac */
uint32_t get_static_nip_by_mac(struct static_lease *st_lease, void *arg) FAST_FUNC;
/* Check to see if an IP is reserved as a static IP */
int is_nip_reserved(struct static_lease *st_lease, uint32_t nip) FAST_FUNC;
/* Print out static leases just to check what's going on (debug code) */
void print_static_leases(struct static_lease **st_lease_pp) FAST_FUNC;
/*** serverpacket.h ***/
int send_offer(struct dhcp_packet *oldpacket) FAST_FUNC;
int send_NAK(struct dhcp_packet *oldpacket) FAST_FUNC;
int send_ACK(struct dhcp_packet *oldpacket, uint32_t yiaddr) FAST_FUNC;
int send_inform(struct dhcp_packet *oldpacket) FAST_FUNC;
/*** files.h ***/
void read_config(const char *file) FAST_FUNC;
void write_leases(void) FAST_FUNC;
void read_leases(const char *file) FAST_FUNC;
struct option_set *find_option(struct option_set *opt_list, uint8_t code) FAST_FUNC;
POP_SAVED_FUNCTION_VISIBILITY
#endif
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