RAW

Functions
err_t	raw_bind (struct raw_pcb *pcb, const ip_addr_t *ipaddr)
err_t	raw_connect (struct raw_pcb *pcb, const ip_addr_t *ipaddr)
void	raw_recv (struct raw_pcb *pcb, raw_recv_fn recv, void *recv_arg)
err_t	raw_sendto (struct raw_pcb *pcb, struct pbuf *p, const ip_addr_t *ipaddr)
err_t	raw_send (struct raw_pcb *pcb, struct pbuf *p)
void	raw_remove (struct raw_pcb *pcb)
struct raw_pcb *	raw_new (u8_t proto)
struct raw_pcb *	raw_new_ip_type (u8_t type, u8_t proto)

Detailed Description

Implementation of raw protocol PCBs for low-level handling of different types of protocols besides (or overriding) those already available in lwIP.

See also

lwIP API

Function Documentation

raw_bind()

err_t raw_bind	(	struct raw_pcb *	pcb,
		const ip_addr_t *	ipaddr
	)

Bind a RAW PCB.

Parameters

pcb	RAW PCB to be bound with a local address ipaddr.
ipaddr	local IP address to bind with. Use IP4_ADDR_ANY to bind to all local interfaces.

Returns

lwIP error code.

• ERR_OK. Successful. No error occurred.
• ERR_USE. The specified IP address is already bound to by another RAW PCB.

See also

raw_disconnect()

raw_connect()

err_t raw_connect	(	struct raw_pcb *	pcb,
		const ip_addr_t *	ipaddr
	)

Connect an RAW PCB. This function is required by upper layers of lwip. Using the raw api you could use raw_sendto() instead

This will associate the RAW PCB with the remote address.

Parameters

pcb	RAW PCB to be connected with remote address ipaddr and port.
ipaddr	remote IP address to connect with.

Returns

lwIP error code

See also

raw_disconnect() and raw_sendto()

raw_new()

struct raw_pcb* raw_new

(

u8_t

proto

)

Create a RAW PCB.

Returns

The RAW PCB which was created. NULL if the PCB data structure could not be allocated.

Parameters

proto

the protocol number of the IPs payload (e.g. IP_PROTO_ICMP)

See also

raw_remove()

raw_new_ip_type()

struct raw_pcb* raw_new_ip_type	(	u8_t	type,
		u8_t	proto
	)

Create a RAW PCB for specific IP type.

Returns

The RAW PCB which was created. NULL if the PCB data structure could not be allocated.

Parameters

type	IP address type, see lwip_ip_addr_type definitions. If you want to listen to IPv4 and IPv6 (dual-stack) packets, supply IPADDR_TYPE_ANY as argument and bind to IP_ANY_TYPE.
proto	the protocol number (next header) of the IPv6 packet payload (e.g. IP6_NEXTH_ICMP6)

See also

raw_remove()

raw_recv()

void raw_recv	(	struct raw_pcb *	pcb,
		raw_recv_fn	recv,
		void *	recv_arg
	)

Set the callback function for received packets that match the raw PCB's protocol and binding.

The callback function MUST either

• eat the packet by calling pbuf_free() and returning non-zero. The packet will not be passed to other raw PCBs or other protocol layers.
• not free the packet, and return zero. The packet will be matched against further PCBs and/or forwarded to another protocol layers.

raw_remove()

void raw_remove

(

struct raw_pcb *

pcb

)

Remove an RAW PCB.

Parameters

pcb	RAW PCB to be removed. The PCB is removed from the list of RAW PCB's and the data structure is freed from memory.

See also

raw_new()

raw_send()

err_t raw_send	(	struct raw_pcb *	pcb,
		struct pbuf *	p
	)

Send the raw IP packet to the address given by raw_connect()

Parameters

pcb	the raw pcb which to send
p	the IP payload to send

raw_sendto()

err_t raw_sendto	(	struct raw_pcb *	pcb,
		struct pbuf *	p,
		const ip_addr_t *	ipaddr
	)

Send the raw IP packet to the given address. Note that actually you cannot modify the IP headers (this is inconsistent with the receive callback where you actually get the IP headers), you can only specify the IP payload here. It requires some more changes in lwIP. (there will be a raw_send() function then.)

Parameters

pcb	the raw pcb which to send
p	the IP payload to send
ipaddr	the destination address of the IP packet