#include "lwip/opt.h"
#include "lwip/netif.h"
#include "lwip/udp.h"

Data Structures
struct	dhcp

struct	dhcp_msg
	minimum set of fields of any DHCP message More...

Macros
#define	DHCP_ACK 5

#define	DHCP_AUTOIP_COOP_STATE_OFF 0
	AUTOIP cooperatation flags. More...

#define	DHCP_AUTOIP_COOP_STATE_ON 1

#define	DHCP_BACKING_OFF 12
	not yet implemented #define DHCP_RELEASING 11 More...

#define	DHCP_BOOTREPLY 2

#define	DHCP_BOOTREQUEST 1

#define	DHCP_BOUND 10

#define	DHCP_CHADDR_LEN 16U

#define	DHCP_CHADDR_OFS 28

#define	DHCP_CHECKING 8

#define	DHCP_CIADDR_OFS 12

#define	DHCP_CLIENT_PORT 68

#define	DHCP_COARSE_TIMER_MSECS (DHCP_COARSE_TIMER_SECS * 1000UL)
	period (in milliseconds) of the application calling dhcp_coarse_tmr() More...

#define	DHCP_COARSE_TIMER_SECS 60
	period (in seconds) of the application calling dhcp_coarse_tmr() More...

#define	DHCP_COOKIE_OFS DHCP_MSG_LEN

#define	DHCP_DECLINE 4

#define	DHCP_DISCOVER 1
	DHCP message types. More...

#define	DHCP_FILE_LEN 128U

#define	DHCP_FILE_OFS 108

#define	DHCP_FINE_TIMER_MSECS 500
	period (in milliseconds) of the application calling dhcp_fine_tmr() More...

#define	DHCP_FLAGS_OFS 10

#define	DHCP_GIADDR_OFS 24

#define	DHCP_HLEN_OFS 2

#define	DHCP_HOPS_OFS 3

#define	DHCP_HTYPE_ETH 1
	DHCP hardware type, currently only ethernet is supported. More...

#define	DHCP_HTYPE_OFS 1

#define	DHCP_INFORM 8

#define	DHCP_INFORMING 7

#define	DHCP_INIT 2

#define	DHCP_MAGIC_COOKIE 0x63825363UL

#define	DHCP_MIN_OPTIONS_LEN 68U

#define	DHCP_MSG_LEN 236

#define	DHCP_NAK 6

#define	DHCP_OFF 0
	DHCP client states. More...

#define	DHCP_OFFER 2

#define	DHCP_OP_OFS 0
	DHCP message item offsets and length. More...

#define	DHCP_OPTION_BOOTFILE 67

#define	DHCP_OPTION_BROADCAST 28

#define	DHCP_OPTION_CLIENT_ID 61

#define	DHCP_OPTION_DNS_SERVER 6

#define	DHCP_OPTION_END 255

#define	DHCP_OPTION_HOSTNAME 12

#define	DHCP_OPTION_IP_TTL 23

#define	DHCP_OPTION_LEASE_TIME 51 /* RFC 2132 9.2, time in seconds, in 4 bytes */

#define	DHCP_OPTION_MAX_MSG_SIZE 57 /* RFC 2132 9.10, message size accepted >= 576 */

#define	DHCP_OPTION_MAX_MSG_SIZE_LEN 2

#define	DHCP_OPTION_MESSAGE_TYPE 53 /* RFC 2132 9.6, important for DHCP */

#define	DHCP_OPTION_MESSAGE_TYPE_LEN 1

#define	DHCP_OPTION_MTU 26

#define	DHCP_OPTION_OVERLOAD 52 /* RFC2132 9.3, use file and/or sname field for options */

#define	DHCP_OPTION_PAD 0
	BootP options. More...

#define	DHCP_OPTION_PARAMETER_REQUEST_LIST 55 /* RFC 2132 9.8, requested option types */

#define	DHCP_OPTION_REQUESTED_IP 50 /* RFC 2132 9.1, requested IP address */
	DHCP options. More...

#define	DHCP_OPTION_ROUTER 3

#define	DHCP_OPTION_SERVER_ID 54 /* RFC 2132 9.7, server IP address */

#define	DHCP_OPTION_SUBNET_MASK 1 /* RFC 2132 3.3 */

#define	DHCP_OPTION_T1 58 /* T1 renewal time */

#define	DHCP_OPTION_T2 59 /* T2 rebinding time */

#define	DHCP_OPTION_TCP_TTL 37

#define	DHCP_OPTION_TFTP_SERVERNAME 66

#define	DHCP_OPTION_US 60

#define	DHCP_OPTIONS_LEN DHCP_MIN_OPTIONS_LEN
	make sure user does not configure this too small More...

#define	DHCP_OPTIONS_OFS (DHCP_MSG_LEN + 4)

#define	DHCP_OVERLOAD_FILE 1

#define	DHCP_OVERLOAD_NONE 0
	possible combinations of overloading the file and sname fields with options More...

#define	DHCP_OVERLOAD_SNAME 2

#define	DHCP_OVERLOAD_SNAME_FILE 3

#define	DHCP_PERMANENT 9

#define	DHCP_REBINDING 4

#define	DHCP_REBOOTING 3

#define	DHCP_RELEASE 7

#define	dhcp_remove_struct(netif) do { (netif)->dhcp = NULL; } while(0)
	Remove a struct dhcp previously set to the netif using dhcp_set_struct() More...

#define	DHCP_RENEWING 5

#define	DHCP_REQUEST 3

#define	DHCP_REQUESTING 1

#define	DHCP_SECS_OFS 8

#define	DHCP_SELECTING 6

#define	DHCP_SERVER_PORT 67

#define	DHCP_SIADDR_OFS 20

#define	DHCP_SNAME_LEN 64U

#define	DHCP_SNAME_OFS 44

#define	DHCP_XID_OFS 4

#define	DHCP_YIADDR_OFS 16

Functions
void	dhcp_arp_reply (struct netif netif, ip_addr_t addr)
	if enabled, check whether the offered IP address is not in use, using ARP More...

void	dhcp_cleanup (struct netif *netif)
	Removes a struct dhcp from a netif. More...

void	dhcp_coarse_tmr (void)
	to be called every minute More...

void	dhcp_fine_tmr (void)
	to be called every half second More...

void	dhcp_inform (struct netif *netif)
	inform server of our manual IP address More...

void	dhcp_network_changed (struct netif *netif)
	Handle a possible change in the network configuration. More...

err_t	dhcp_release (struct netif *netif)
	release the DHCP lease, usually called before dhcp_stop() More...

err_t	dhcp_renew (struct netif *netif)
	enforce early lease renewal (not needed normally) More...

PACK_STRUCT_END void	dhcp_set_struct (struct netif netif, struct dhcp dhcp)
	Set a statically allocated struct dhcp to work with. More...

err_t	dhcp_start (struct netif *netif)
	start DHCP configuration More...

void	dhcp_stop (struct netif *netif)
	stop DHCP configuration More...

Variables
PACK_STRUCT_BEGIN struct dhcp_msg	PACK_STRUCT_STRUCT

#define DHCP_ACK 5

Referenced by dhcp_parse_reply(), and dhcp_recv().

#define DHCP_AUTOIP_COOP_STATE_OFF 0

AUTOIP cooperatation flags.

Referenced by dhcp_bind(), dhcp_discover(), dhcp_network_changed(), and dhcp_stop().

#define DHCP_AUTOIP_COOP_STATE_ON 1

Referenced by dhcp_bind(), dhcp_discover(), dhcp_network_changed(), and dhcp_stop().

#define DHCP_BACKING_OFF 12

not yet implemented #define DHCP_RELEASING 11

Referenced by dhcp_decline(), dhcp_handle_nak(), and dhcp_timeout().

#define DHCP_BOOTREPLY 2

Referenced by dhcp_recv().

#define DHCP_BOOTREQUEST 1

Referenced by dhcp_create_msg().

#define DHCP_BOUND 10

Referenced by dhcp_bind(), dhcp_network_changed(), dhcp_t1_timeout(), and dhcp_t2_timeout().

#define DHCP_CHADDR_LEN 16U

Referenced by dhcp_create_msg().

#define DHCP_CHADDR_OFS 28

#define DHCP_CHECKING 8

Referenced by dhcp_arp_reply(), dhcp_check(), and dhcp_timeout().

#define DHCP_CIADDR_OFS 12

#define DHCP_CLIENT_PORT 68

Referenced by dhcp_inform(), dhcp_start(), and udp_input().

#define DHCP_COARSE_TIMER_MSECS (DHCP_COARSE_TIMER_SECS * 1000UL)

period (in milliseconds) of the application calling dhcp_coarse_tmr()

Referenced by dhcp_timer_coarse(), and sys_timeouts_init().

#define DHCP_COARSE_TIMER_SECS 60

period (in seconds) of the application calling dhcp_coarse_tmr()

Referenced by dhcp_bind().

#define DHCP_COOKIE_OFS DHCP_MSG_LEN

#define DHCP_DECLINE 4

Referenced by dhcp_create_msg(), and dhcp_decline().

#define DHCP_DISCOVER 1

DHCP message types.

Referenced by dhcp_discover().

#define DHCP_FILE_LEN 128U

Referenced by dhcp_create_msg(), and dhcp_parse_reply().

#define DHCP_FILE_OFS 108

Referenced by dhcp_parse_reply().

#define DHCP_FINE_TIMER_MSECS 500

period (in milliseconds) of the application calling dhcp_fine_tmr()

Referenced by dhcp_check(), dhcp_decline(), dhcp_discover(), dhcp_rebind(), dhcp_reboot(), dhcp_release(), dhcp_renew(), dhcp_select(), dhcp_timer_fine(), and sys_timeouts_init().

#define DHCP_FLAGS_OFS 10

#define DHCP_GIADDR_OFS 24

#define DHCP_HLEN_OFS 2

#define DHCP_HOPS_OFS 3

#define DHCP_HTYPE_ETH 1

DHCP hardware type, currently only ethernet is supported.

Referenced by dhcp_create_msg().

#define DHCP_HTYPE_OFS 1

#define DHCP_INFORM 8

Referenced by dhcp_create_msg(), and dhcp_inform().

#define DHCP_INFORMING 7

#define DHCP_INIT 2

#define DHCP_MAGIC_COOKIE 0x63825363UL

Referenced by dhcp_create_msg().

#define DHCP_MIN_OPTIONS_LEN 68U

Referenced by dhcp_option_trailer().

#define DHCP_MSG_LEN 236

#define DHCP_NAK 6

Referenced by dhcp_recv().

#define DHCP_OFF 0

DHCP client states.

Referenced by dhcp_network_changed(), dhcp_release(), and dhcp_stop().

#define DHCP_OFFER 2

Referenced by dhcp_recv().

#define DHCP_OP_OFS 0

DHCP message item offsets and length.

#define DHCP_OPTION_BOOTFILE 67

#define DHCP_OPTION_BROADCAST 28

Referenced by dhcp_discover(), and dhcp_select().

#define DHCP_OPTION_CLIENT_ID 61

#define DHCP_OPTION_DNS_SERVER 6

Referenced by dhcp_discover(), dhcp_parse_reply(), and dhcp_select().

#define DHCP_OPTION_END 255

Referenced by dhcp_option_trailer(), and dhcp_parse_reply().

#define DHCP_OPTION_HOSTNAME 12

Referenced by dhcp_rebind(), dhcp_renew(), and dhcp_select().

#define DHCP_OPTION_IP_TTL 23

#define DHCP_OPTION_LEASE_TIME 51 /* RFC 2132 9.2, time in seconds, in 4 bytes */

Referenced by dhcp_parse_reply().

#define DHCP_OPTION_MAX_MSG_SIZE 57 /* RFC 2132 9.10, message size accepted >= 576 */

Referenced by dhcp_discover(), dhcp_inform(), dhcp_rebind(), dhcp_reboot(), dhcp_renew(), and dhcp_select().

#define DHCP_OPTION_MAX_MSG_SIZE_LEN 2

Referenced by dhcp_discover(), dhcp_inform(), dhcp_rebind(), dhcp_reboot(), dhcp_renew(), and dhcp_select().

#define DHCP_OPTION_MESSAGE_TYPE 53 /* RFC 2132 9.6, important for DHCP */

Referenced by dhcp_create_msg(), and dhcp_parse_reply().

#define DHCP_OPTION_MESSAGE_TYPE_LEN 1

Referenced by dhcp_create_msg().

#define DHCP_OPTION_MTU 26

#define DHCP_OPTION_OVERLOAD 52 /* RFC2132 9.3, use file and/or sname field for options */

Referenced by dhcp_parse_reply().

#define DHCP_OPTION_PAD 0

BootP options.

Referenced by dhcp_parse_reply().

#define DHCP_OPTION_PARAMETER_REQUEST_LIST 55 /* RFC 2132 9.8, requested option types */

Referenced by dhcp_discover(), and dhcp_select().

#define DHCP_OPTION_REQUESTED_IP 50 /* RFC 2132 9.1, requested IP address */

DHCP options.

Referenced by dhcp_decline(), dhcp_rebind(), dhcp_reboot(), dhcp_renew(), and dhcp_select().

#define DHCP_OPTION_ROUTER 3

Referenced by dhcp_discover(), dhcp_parse_reply(), and dhcp_select().

#define DHCP_OPTION_SERVER_ID 54 /* RFC 2132 9.7, server IP address */

Referenced by dhcp_parse_reply(), dhcp_rebind(), dhcp_renew(), and dhcp_select().

#define DHCP_OPTION_SUBNET_MASK 1 /* RFC 2132 3.3 */

Referenced by dhcp_discover(), dhcp_parse_reply(), and dhcp_select().

#define DHCP_OPTION_T1 58 /* T1 renewal time */

Referenced by dhcp_parse_reply().

#define DHCP_OPTION_T2 59 /* T2 rebinding time */

Referenced by dhcp_parse_reply().

#define DHCP_OPTION_TCP_TTL 37

#define DHCP_OPTION_TFTP_SERVERNAME 66

#define DHCP_OPTION_US 60

#define DHCP_OPTIONS_LEN DHCP_MIN_OPTIONS_LEN

make sure user does not configure this too small

allow this to be configured in lwipopts.h, but not too small set this to be sufficient for your options in outgoing DHCP msgs

Referenced by dhcp_create_msg(), dhcp_decline(), dhcp_discover(), dhcp_inform(), dhcp_option(), dhcp_option_byte(), dhcp_option_long(), dhcp_option_short(), dhcp_option_trailer(), dhcp_rebind(), dhcp_reboot(), dhcp_release(), dhcp_renew(), and dhcp_select().

#define DHCP_OPTIONS_OFS (DHCP_MSG_LEN + 4)

Referenced by dhcp_parse_reply().

#define DHCP_OVERLOAD_FILE 1

Referenced by dhcp_parse_reply().

#define DHCP_OVERLOAD_NONE 0

possible combinations of overloading the file and sname fields with options

#define DHCP_OVERLOAD_SNAME 2

Referenced by dhcp_parse_reply().

#define DHCP_OVERLOAD_SNAME_FILE 3

Referenced by dhcp_parse_reply().

#define DHCP_PERMANENT 9

#define DHCP_REBINDING 4

Referenced by dhcp_create_msg(), dhcp_network_changed(), dhcp_rebind(), dhcp_recv(), and dhcp_timeout().

#define DHCP_REBOOTING 3

Referenced by dhcp_network_changed(), dhcp_reboot(), dhcp_recv(), and dhcp_timeout().

#define DHCP_RELEASE 7

Referenced by dhcp_release().

#define dhcp_remove_struct ( netif ) do { (netif)->dhcp = NULL; } while(0)

Remove a struct dhcp previously set to the netif using dhcp_set_struct()

#define DHCP_RENEWING 5

Referenced by dhcp_create_msg(), dhcp_network_changed(), dhcp_recv(), dhcp_renew(), dhcp_t1_timeout(), dhcp_t2_timeout(), and dhcp_timeout().

#define DHCP_REQUEST 3

Referenced by dhcp_create_msg(), dhcp_rebind(), dhcp_reboot(), dhcp_renew(), and dhcp_select().

#define DHCP_REQUESTING 1

Referenced by dhcp_recv(), dhcp_select(), dhcp_t1_timeout(), dhcp_t2_timeout(), and dhcp_timeout().

#define DHCP_SECS_OFS 8

#define DHCP_SELECTING 6

Referenced by dhcp_discover(), dhcp_recv(), and dhcp_timeout().

#define DHCP_SERVER_PORT 67

Referenced by dhcp_decline(), dhcp_discover(), dhcp_inform(), dhcp_rebind(), dhcp_reboot(), dhcp_release(), dhcp_renew(), dhcp_select(), dhcp_start(), and udp_input().

#define DHCP_SIADDR_OFS 20

#define DHCP_SNAME_LEN 64U

Referenced by dhcp_create_msg(), and dhcp_parse_reply().

#define DHCP_SNAME_OFS 44

Referenced by dhcp_parse_reply().

#define DHCP_XID_OFS 4

#define DHCP_YIADDR_OFS 16

void dhcp_arp_reply	(	struct netif *	netif,
		ip_addr_t *	addr
	)

if enabled, check whether the offered IP address is not in use, using ARP

Parameters

netif	the network interface on which the reply was received
addr	The IP address we received a reply from

References netif::dhcp, DHCP_CHECKING, DHCP_DEBUG, dhcp_decline(), ip4_addr_get_u32, ip_addr_cmp, LWIP_DBG_LEVEL_WARNING, LWIP_DBG_STATE, LWIP_DBG_TRACE, LWIP_DEBUGF, LWIP_ERROR(), NULL, dhcp::offered_ip_addr, dhcp::state, and X32_F.

Referenced by etharp_arp_input().

void dhcp_cleanup ( struct netif * netif )

Removes a struct dhcp from a netif.

ATTENTION: Only use this when not using dhcp_set_struct() to allocate the struct dhcp since the memory is passed back to the heap.

Parameters

netif the netif from which to remove the struct dhcp

References netif::dhcp, LWIP_ASSERT, mem_free(), and NULL.

void dhcp_coarse_tmr ( void )

to be called every minute

References netif::dhcp, DHCP_DEBUG, dhcp_t1_timeout(), dhcp_t2_timeout(), LWIP_DBG_STATE, LWIP_DBG_TRACE, LWIP_DEBUGF, netif_list, netif::next, NULL, dhcp::t1_timeout, and dhcp::t2_timeout.

Referenced by dhcp_timer_coarse().

void dhcp_fine_tmr ( void )

to be called every half second

A DHCP server is expected to respond within a short period of time. This timer checks whether an outstanding DHCP request is timed out.

References netif::dhcp, DHCP_DEBUG, dhcp_timeout(), LWIP_DBG_STATE, LWIP_DBG_TRACE, LWIP_DEBUGF, netif_list, netif::next, NULL, and dhcp::request_timeout.

Referenced by dhcp_timer_fine().

void dhcp_inform ( struct netif * netif )

inform server of our manual IP address

This informs DHCP servers of our fixed IP address configuration by sending an INFORM message. It does not involve DHCP address configuration, it is just here to be nice to the network.

Parameters

netif The lwIP network interface

References netif::dhcp, DHCP_CLIENT_PORT, dhcp_create_msg(), DHCP_DEBUG, dhcp_delete_msg(), DHCP_INFORM, DHCP_MAX_MSG_LEN, dhcp_option(), DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN, dhcp_option_short(), dhcp_option_trailer(), DHCP_OPTIONS_LEN, DHCP_SERVER_PORT, dhcp_set_state(), ERR_OK, IP_ADDR_ANY, IP_ADDR_BROADCAST, LWIP_DBG_LEVEL_SERIOUS, LWIP_DBG_STATE, LWIP_DBG_TRACE, LWIP_DEBUGF, LWIP_ERROR(), NULL, dhcp::options_out_len, dhcp::p_out, pbuf_realloc(), dhcp::pcb, SOF_BROADCAST, udp_bind(), udp_new(), udp_remove(), and udp_sendto_if().

void dhcp_network_changed ( struct netif * netif )

Handle a possible change in the network configuration.

This enters the REBOOTING state to verify that the currently bound address is still valid.

References netif::dhcp, DHCP_AUTOIP_COOP_STATE_OFF, DHCP_AUTOIP_COOP_STATE_ON, DHCP_BOUND, dhcp_discover(), DHCP_OFF, DHCP_REBINDING, dhcp_reboot(), DHCP_REBOOTING, DHCP_RENEWING, netif_set_down(), dhcp::state, and dhcp::tries.

Referenced by netif_set_link_up().

err_t dhcp_release ( struct netif * netif )

release the DHCP lease, usually called before dhcp_stop()

Parameters

netif network interface which must release its lease

References netif::dhcp, dhcp_create_msg(), DHCP_DEBUG, dhcp_delete_msg(), DHCP_FINE_TIMER_MSECS, DHCP_OFF, dhcp_option_trailer(), DHCP_OPTIONS_LEN, DHCP_RELEASE, DHCP_SERVER_PORT, dhcp_set_state(), ERR_OK, IP_ADDR_ANY, ip_addr_set_zero, LWIP_DBG_LEVEL_SERIOUS, LWIP_DBG_STATE, LWIP_DBG_TRACE, LWIP_DEBUGF, netif_set_down(), netif_set_gw(), netif_set_ipaddr(), netif_set_netmask(), dhcp::offered_gw_addr, dhcp::offered_ip_addr, dhcp::offered_sn_mask, dhcp::offered_t0_lease, dhcp::offered_t1_renew, dhcp::offered_t2_rebind, dhcp::options_out_len, dhcp::p_out, pbuf_realloc(), dhcp::pcb, dhcp::request_timeout, dhcp::server_ip_addr, dhcp::tries, U16_F, and udp_sendto_if().

Referenced by dhcp_timeout().

err_t dhcp_renew ( struct netif * netif )

enforce early lease renewal (not needed normally)

Parameters

netif network interface which must renew its lease

References netif::dhcp, dhcp_create_msg(), DHCP_DEBUG, dhcp_delete_msg(), DHCP_FINE_TIMER_MSECS, DHCP_MAX_MSG_LEN, dhcp_option(), dhcp_option_byte(), DHCP_OPTION_HOSTNAME, dhcp_option_long(), DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN, DHCP_OPTION_REQUESTED_IP, DHCP_OPTION_SERVER_ID, dhcp_option_short(), dhcp_option_trailer(), DHCP_OPTIONS_LEN, DHCP_RENEWING, DHCP_REQUEST, DHCP_SERVER_PORT, dhcp_set_state(), ERR_OK, LWIP_ASSERT, LWIP_DBG_LEVEL_SERIOUS, LWIP_DBG_STATE, LWIP_DBG_TRACE, LWIP_DEBUGF, ntohl, NULL, dhcp::offered_ip_addr, dhcp::options_out_len, dhcp::p_out, pbuf_realloc(), dhcp::pcb, dhcp::request_timeout, dhcp::server_ip_addr, dhcp::tries, U16_F, and udp_sendto_if().

Referenced by dhcp_t1_timeout(), and dhcp_timeout().

PACK_STRUCT_END void dhcp_set_struct	(	struct netif *	netif,
		struct dhcp *	dhcp
	)

Set a statically allocated struct dhcp to work with.

Using this prevents dhcp_start to allocate it using mem_malloc.

Parameters

netif	the netif for which to set the struct dhcp
dhcp	(uninitialised) dhcp struct allocated by the application

References netif::dhcp, LWIP_ASSERT, and NULL.

err_t dhcp_start ( struct netif * netif )

start DHCP configuration

If no DHCP client instance was attached to this interface, a new client is created first. If a DHCP client instance was already present, it restarts negotiation.

Parameters

netif The lwIP network interface

Returns

lwIP error code