uIP packet forwarding [The uIP TCP/IP stack]

Collaboration diagram for uIP packet forwarding:

Data Structures
struct	tcpip_hdr
struct	icmpip_hdr
struct	fwcache_entry
struct	uip_fw_netif
Files
file	uip-fw.c
file	uip-fw.h
Defines
#define	ICMP_ECHO   8
#define	ICMP_TE   11
#define	BUF   ((struct tcpip_hdr *)&uip_buf[UIP_LLH_LEN])
#define	ICMPBUF   ((struct icmpip_hdr *)&uip_buf[UIP_LLH_LEN])
#define	FWCACHE_SIZE   2
#define	FW_TIME   20
#define	UIP_FW_NETIF(ip1, ip2, ip3, ip4, nm1, nm2, nm3, nm4, outputfunc)
#define	uip_fw_setipaddr(netif, addr)
#define	uip_fw_setnetmask(netif, addr)
#define	UIP_FW_LOCAL
#define	UIP_FW_OK
#define	UIP_FW_FORWARDED
#define	UIP_FW_ZEROLEN
#define	UIP_FW_TOOLARGE
#define	UIP_FW_NOROUTE
#define	UIP_FW_DROPPED
Functions
void	uip_fw_init (void)
u8_t	uip_fw_output (void)
u8_t	uip_fw_forward (void)
void	uip_fw_register (struct uip_fw_netif *netif)
void	uip_fw_default (struct uip_fw_netif *netif)
void	uip_fw_periodic (void)
Variables
u16_t	tcpip_hdr::len
u16_t	tcpip_hdr::ipid
u16_t	tcpip_hdr::ipoffset
u8_t	tcpip_hdr::ttl
u8_t	tcpip_hdr::proto
u16_t	tcpip_hdr::ipchksum
u16_t	tcpip_hdr::srcipaddr [2]
u16_t	tcpip_hdr::destipaddr [2]
u16_t	tcpip_hdr::srcport
u16_t	tcpip_hdr::destport
u8_t	tcpip_hdr::seqno [4]
u8_t	tcpip_hdr::ackno [4]
u8_t	tcpip_hdr::tcpoffset
u8_t	tcpip_hdr::flags
u8_t	tcpip_hdr::wnd [2]
u16_t	tcpip_hdr::tcpchksum
u8_t	tcpip_hdr::urgp [2]
u8_t	tcpip_hdr::optdata [4]
u16_t	icmpip_hdr::ipchksum
u16_t	icmpip_hdr::srcipaddr [2]
u16_t	icmpip_hdr::destipaddr [2]
u8_t	icmpip_hdr::type
u8_t	icmpip_hdr::icode
u16_t	icmpip_hdr::icmpchksum
u16_t	icmpip_hdr::id
u16_t	icmpip_hdr::seqno
u8_t	icmpip_hdr::payload [1]
u16_t	fwcache_entry::srcipaddr [2]
u16_t	fwcache_entry::destipaddr [2]
u16_t	fwcache_entry::ipid
u8_t	fwcache_entry::proto
u8_t	fwcache_entry::unused

---

Define Documentation

#define UIP_FW_DROPPED

An error message that indicates that a packet that should be forwarded or output was dropped.

Definition at line 171 of file uip-fw.h.

#define UIP_FW_FORWARDED

A non-error message that indicates that a packet was forwarded.

Definition at line 139 of file uip-fw.h.

#define UIP_FW_LOCAL

A non-error message that indicates that a packet should be processed locally.

Definition at line 125 of file uip-fw.h.

#define UIP_FW_NETIF	(		ip1,
			ip2,
			ip3,
			ip4,
			nm1,
			nm2,
			nm3,
			nm4,
			outputfunc
	)

Intantiating macro for a uIP network interface.

Example:

 struct uip_fw_netif slipnetif =
   {UIP_FW_NETIF(192,168,76,1, 255,255,255,0, slip_output)};

Parameters:

	ip1,ip2,ip3,ip4	The IP address of the network interface.
	nm1,nm2,nm3,nm4	The netmask of the network interface.
	outputfunc	A pointer to the output function of the network interface.

Definition at line 80 of file uip-fw.h.

#define UIP_FW_NOROUTE

An error message that indicates that no suitable interface could be found for an outbound packet.

Definition at line 163 of file uip-fw.h.

#define UIP_FW_OK

A non-error message that indicates that something went OK.

Definition at line 132 of file uip-fw.h.

#define uip_fw_setipaddr	(		netif,
			addr
	)

Set the IP address of a network interface.

Parameters:

	netif	A pointer to the uip_fw_netif structure for the network interface.
	addr	A pointer to an IP address.

Definition at line 95 of file uip-fw.h.

#define uip_fw_setnetmask	(		netif,
			addr
	)

Set the netmask of a network interface.

Parameters:

	netif	A pointer to the uip_fw_netif structure for the network interface.
	addr	A pointer to an IP address representing the netmask.

Definition at line 107 of file uip-fw.h.

#define UIP_FW_TOOLARGE

An error message that indicates that a packet that was too large for the outbound network interface was detected.

Definition at line 155 of file uip-fw.h.

#define UIP_FW_ZEROLEN

A non-error message that indicates that a zero-length packet transmission was attempted, and that no packet was sent.

Definition at line 147 of file uip-fw.h.

---

Function Documentation

void uip_fw_default

(

struct uip_fw_netif *

netif

)

Register a default network interface.

All packets that don't go out on any of the other interfaces will be routed to the default interface.

Parameters:

netif

A pointer to the network interface that is to be registered.

u8_t uip_fw_forward

(

void

)

Forward an IP packet in the uip_buf buffer.

Returns:

UIP_FW_FORWARDED if the packet was forwarded, UIP_FW_LOCAL if the packet should be processed locally.

void uip_fw_init

(

void

)

Initialize the uIP packet forwarding module.

u8_t uip_fw_output

(

void

)

Output an IP packet on the correct network interface.

The IP packet should be present in the uip_buf buffer and its length in the global uip_len variable.

Return values:

	UIP_FW_ZEROLEN	Indicates that a zero-length packet transmission was attempted and that no packet was sent.
	UIP_FW_NOROUTE	No suitable network interface could be found for the outbound packet, and the packet was not sent.

Returns:

The return value from the actual network interface output function is passed unmodified as a return value.

void uip_fw_periodic

(

void

)

Perform periodic processing.

void uip_fw_register

(

struct uip_fw_netif *

netif

)

Register a network interface with the forwarding module.

Parameters:

netif

A pointer to the network interface that is to be registered.