networking/udhcp/common.h

/* vi: set sw=4 ts=4: */
/* common.h
 *
 * Russ Dill <Russ.Dill@asu.edu> September 2001
 * Rewritten by Vladimir Oleynik <dzo@simtreas.ru> (C) 2003
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#ifndef _COMMON_H
#define _COMMON_H

#include "libbb.h"

#define DEFAULT_SCRIPT  "/usr/share/udhcpc/default.script"

#define SERVER_PORT  67
#define CLIENT_PORT  68

extern const uint8_t MAC_BCAST_ADDR[6]; /* six all-ones */

/*** packet.h ***/

#include <netinet/udp.h>
#include <netinet/ip.h>

#define DHCP_OPTIONS_BUFSIZE  308

struct dhcpMessage {
	uint8_t op;
	uint8_t htype;
	uint8_t hlen;
	uint8_t hops;
	uint32_t xid;
	uint16_t secs;
	uint16_t flags;
	uint32_t ciaddr;
	uint32_t yiaddr;
	uint32_t siaddr;
	uint32_t giaddr;
	uint8_t chaddr[16];
	uint8_t sname[64];
	uint8_t file[128];
	uint32_t cookie;
	uint8_t options[DHCP_OPTIONS_BUFSIZE + CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS];
} ATTRIBUTE_PACKED;

struct udp_dhcp_packet {
	struct iphdr ip;
	struct udphdr udp;
	struct dhcpMessage data;
} ATTRIBUTE_PACKED;

/* Let's see whether compiler understood us right */
struct BUG_bad_sizeof_struct_udp_dhcp_packet {
	char BUG_bad_sizeof_struct_udp_dhcp_packet
		[(sizeof(struct udp_dhcp_packet) != 576 + CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS) ? -1 : 1];
};

uint16_t udhcp_checksum(void *addr, int count);

void udhcp_init_header(struct dhcpMessage *packet, char type);

int udhcp_recv_packet(struct dhcpMessage *packet, int fd);
int udhcp_send_raw_packet(struct dhcpMessage *payload,
		uint32_t source_ip, int source_port,
		uint32_t dest_ip, int dest_port,
		const uint8_t *dest_arp, int ifindex);
int udhcp_send_kernel_packet(struct dhcpMessage *payload,
		uint32_t source_ip, int source_port,
		uint32_t dest_ip, int dest_port);


/**/

void udhcp_run_script(struct dhcpMessage *packet, const char *name);

// Still need to clean these up...

/* from options.h */
#define get_option		udhcp_get_option
#define end_option		udhcp_end_option
#define add_option_string	udhcp_add_option_string
#define add_simple_option	udhcp_add_simple_option
/* from socket.h */
#define listen_socket		udhcp_listen_socket
#define read_interface		udhcp_read_interface

void udhcp_sp_setup(void);
int udhcp_sp_fd_set(fd_set *rfds, int extra_fd);
int udhcp_sp_read(const fd_set *rfds);
int raw_socket(int ifindex);
int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t *arp);
int listen_socket(/*uint32_t ip,*/ int port, const char *inf);
/* Returns 1 if no reply received */
int arpping(uint32_t test_ip, uint32_t from_ip, uint8_t *from_mac, const char *interface);

#if ENABLE_FEATURE_UDHCP_DEBUG
# define DEBUG(str, args...) bb_info_msg("### " str, ## args)
#else
# define DEBUG(str, args...) do {;} while (0)
#endif

#endif