Tiny DHCP Server.

#include "conf_tinyservices.h"
#include "tinyservices.h"
#include "wifi_private.h"
#include "lwip/dhcp.h"
#include "lwip/tcpip.h"
#include <string.h>

Macros
#define	LWIP_DHCP_MAX_CLIENT 8

Functions
static uint16_t	lwip_dhcp_find_option (struct pbuf pbuf_in, uint8_t option, uint8_t opt_val, uint8_t *opt_size)
	Find an option in a DHCP packet. More...

static ip_addr_t	lwip_dhcp_get_ip_address (uint8_t *mac)
	Find a IP address for MAC. More...

void	lwip_dhcp_register_mac (uint8_t *mac)

static void	lwip_dhcp_server_fn (void arg, struct udp_pcb dhcp_pcb_recv, struct pbuf pbuf_in, struct ip_addr client_addr, uint16_t port)
	Receive DHCP discover, request and inform packets and respond to them by supplying one IP Address for the client and setting the DNS server address. More...

void	lwip_dhcp_unregister_mac (uint8_t *mac)

static void	lwip_dhcpserver_start_threadsafe (void *arg)
	Start the Tiny DNS Server. More...

void	lwip_tiny_dhcpserver_start (void)
	Start the Tiny DHCP Server. More...

void	lwip_tiny_dhcpserver_stop (void)
	Stop a Tiny DHCP Server. More...

static void	lwip_tiny_dhcpserver_stop_threadsafe (void *arg)
	Stop a Tiny DHCP Server. More...

Variables
static struct udp_pcb *	dhcp_pcb = 0

static ip_addr_t	ip_addr_c_broadcast = { 0xff05a8c0 }

static uint8_t	lwip_dhcp_known_mac [LWIP_DHCP_MAX_CLIENT][6]

#define LWIP_DHCP_MAX_CLIENT 8

Referenced by lwip_dhcp_get_ip_address(), lwip_dhcp_register_mac(), lwip_dhcp_unregister_mac(), and lwip_dhcpserver_start_threadsafe().

static uint16_t lwip_dhcp_find_option	(	struct pbuf *	pbuf_in,
		uint8_t	option,
		uint8_t *	opt_val,
		uint8_t *	opt_size
	)

static

Find an option in a DHCP packet.

Parameters

pbuf_in	the pbuf containing the a DHCP packet.
option	an unsigned char representing the option to search for.
opt_val	a pointer to place the value of the option located.
opt_size	a pointer to the size of the option located.

Returns: 1 if option found, 0 if option not found.

References DHCP_OPTIONS_OFS, pbuf_copy_partial(), and pbuf_get_at().

Referenced by lwip_dhcp_server_fn().

static ip_addr_t lwip_dhcp_get_ip_address ( uint8_t * mac )

static

Find a IP address for MAC.

Returns: IP address if available, NULL if not.

References lwip_dhcp_known_mac, and LWIP_DHCP_MAX_CLIENT.

Referenced by lwip_dhcp_server_fn().

void lwip_dhcp_register_mac ( uint8_t * mac )

References lwip_dhcp_known_mac, LWIP_DHCP_MAX_CLIENT, and lwip_dhcp_unregister_mac().

Referenced by lwip_dhcp_server_fn().

static void lwip_dhcp_server_fn	(	void *	arg,
		struct udp_pcb *	dhcp_pcb_recv,
		struct pbuf *	pbuf_in,
		struct ip_addr *	client_addr,
		uint16_t	port
	)

static

Receive DHCP discover, request and inform packets and respond to them by supplying one IP Address for the client and setting the DNS server address.

Parameters

arg	unused.
dhcp_pcb	a pointer to the pcb that DHCP packets are received on.
pbuf_in	a pointer to the pbuf containing the DHCP packet.
client_addr	the IP Address (if any) that originated the DHCP traffic.
port	unused.

References AP_ADDR_IP, Assert, DHCP_ACK, DHCP_BOOTREPLY, DHCP_CHADDR_OFS, DHCP_CLIENT_PORT, DHCP_COOKIE_OFS, DHCP_DISCOVER, DHCP_FLAGS_OFS, DHCP_INFORM, DHCP_MAGIC_COOKIE, DHCP_NAK, DHCP_OFFER, DHCP_OP_OFS, DHCP_OPTION_DNS_SERVER, DHCP_OPTION_DOMAIN_NAME, DHCP_OPTION_END, DHCP_OPTION_LEASE_TIME, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_REQUESTED_IP, DHCP_OPTION_ROUTER, DHCP_OPTION_SERVER_ID, DHCP_OPTION_SUBNET_MASK, DHCP_OPTION_T1, DHCP_OPTION_T2, DHCP_OPTION_VENDOR_SPECIFIC_INFO, DHCP_OPTIONS_OFS, DHCP_REQUEST, DHCP_RESPONSE_DEFAULT_SIZE, DHCP_SECS_OFS, DHCP_SIADDR_OFS, DHCP_YIADDR_OFS, DOMAIN_NAME, DOMAIN_NAME_LEN, ERR_OK, flags, ip_addr_c_broadcast, lwip_dhcp_find_option(), lwip_dhcp_get_ip_address(), lwip_dhcp_register_mac(), NULL, pbuf_alloc(), pbuf_copy(), pbuf_free(), PBUF_POOL, pbuf_read8(), pbuf_realloc(), pbuf_take_partial(), PBUF_TRANSPORT, pbuf_write32be(), pbuf_write8(), pbuf_write_ip(), SANE_LEASE_TIME, SANE_REBINDING_TIME, SANE_RENEWAL_TIME, SN_MASK_IP, pbuf::tot_len, udp_sendto(), and UNUSED.

Referenced by lwip_dhcpserver_start_threadsafe().

void lwip_dhcp_unregister_mac ( uint8_t * mac )

References lwip_dhcp_known_mac, and LWIP_DHCP_MAX_CLIENT.

Referenced by lwip_dhcp_register_mac().

static void lwip_dhcpserver_start_threadsafe ( void * arg )

static

Start the Tiny DNS Server.

Create a new UDP PCB, bind that PCB to the DHCP_SERVER_PORT and set up a receiver for that PCB.

This variant of the start function must only be called from within LWIP's main thread.

This function must be invoked via lwip_tiny_dhcpserver_start

References Assert, DHCP_SERVER_PORT, IP_ADDR_ANY, lwip_dhcp_known_mac, LWIP_DHCP_MAX_CLIENT, lwip_dhcp_server_fn(), udp_bind(), udp_new(), udp_recv(), and UNUSED.

Referenced by lwip_tiny_dhcpserver_start().

void lwip_tiny_dhcpserver_start ( void )

Start the Tiny DHCP Server.

Start Tiny DHCP server.

Create a new UDP PCB, bind that PCB to the DHCP_SERVER_PORT and set up a receiver for that PCB.

Thread-safe variant of this function. This function posts the LWIP-thread-only variant of this function (with dummy argument) to the LWIP thread's mailbox and returns.

NOTE: This function cannot wait. It may be called from within the LWIP main thread of execution.

References lwip_dhcpserver_start_threadsafe(), and tcpip_callback.

Referenced by net_interface_up_imp().

void lwip_tiny_dhcpserver_stop ( void )

Stop a Tiny DHCP Server.

Stop Tiny DHCP server.

Disconnect and remove the UDP PCB.

Thread-safe variant of this function. This function posts the lwip-main-thread only function and a dummy argument to the main lwip thread.

NOTE: This function cannot wait. It may be called from within the LWIP main thread of execution.

References lwip_tiny_dhcpserver_stop_threadsafe(), and tcpip_callback.

Referenced by net_interface_down_imp().

static void lwip_tiny_dhcpserver_stop_threadsafe ( void * arg )