Forwarding table

Detailed Description

Files
file	ft.h
	Forwarding table definitions.

Data Structures
struct	gnrc_ipv6_nib_ft_t
	Forwarding table entry view on NIB. More...

Functions
int	gnrc_ipv6_nib_ft_get (const ipv6_addr_t *dst, gnrc_pktsnip_t *pkt, gnrc_ipv6_nib_ft_t *fte)
	Gets the best matching forwarding table entry to a destination.
int	gnrc_ipv6_nib_ft_add (const ipv6_addr_t *dst, unsigned dst_len, const ipv6_addr_t *next_hop, unsigned iface, uint32_t lifetime)
	Adds a new route to the forwarding table.
void	gnrc_ipv6_nib_ft_del (const ipv6_addr_t *dst, unsigned dst_len)
	Deletes a route from forwarding table.
bool	gnrc_ipv6_nib_ft_iter (const ipv6_addr_t *next_hop, unsigned iface, void **state, gnrc_ipv6_nib_ft_t *fte)
	Iterates over all forwarding table entries in the NIB.
void	gnrc_ipv6_nib_ft_print (const gnrc_ipv6_nib_ft_t *fte)
	Prints a forwarding table entry.

Function Documentation

gnrc_ipv6_nib_ft_add()

int gnrc_ipv6_nib_ft_add	(	const ipv6_addr_t *	dst,
		unsigned	dst_len,
		const ipv6_addr_t *	next_hop,
		unsigned	iface,
		uint32_t	lifetime
	)

Adds a new route to the forwarding table.

If dst is the default route, the route will be configured to be the default route.

Parameters

[in]	dst	The destination to the route. May be NULL or :: for default route.
[in]	dst_len	The prefix length of dst in bits. May be 0 for default route.
[in]	next_hop	The next hop to dst/dst_len. May be NULL, if dst/dst_len is no the default route.
[in]	iface	The interface to next_hop. May not be 0.
[in]	lifetime	Lifetime of the route in seconds. 0 for infinite lifetime.

Returns

0, on success.

-EINVAL, if a parameter was of invalid value.

-ENOMEM, if there was no space left in forwarding table.

gnrc_ipv6_nib_ft_del()

void gnrc_ipv6_nib_ft_del	(	const ipv6_addr_t *	dst,
		unsigned	dst_len
	)

Deletes a route from forwarding table.

If dst is the default route, the function assures, that the current primary default route is removed first.

Parameters

[in]	dst	The destination of the route. May be NULL or :: for default route.
[in]	dst_len	The prefix length of dst in bits. May be 0 for default route.

gnrc_ipv6_nib_ft_get()

int gnrc_ipv6_nib_ft_get	(	const ipv6_addr_t *	dst,
		gnrc_pktsnip_t *	pkt,
		gnrc_ipv6_nib_ft_t *	fte
	)

Gets the best matching forwarding table entry to a destination.

Precondition

(dst != NULL) && (fte != NULL)

Parameters

[in]	dst	The destination.
[in]	pkt	Packet that is supposed to go to that destination (is handed over to a reactive routing protocol if one exists on the interface found and no route is found)
[out]	fte	The resulting forwarding table entry.

Returns

0, on success.

-ENETUNREACH, if no route was found.

gnrc_ipv6_nib_ft_iter()

bool gnrc_ipv6_nib_ft_iter	(	const ipv6_addr_t *	next_hop,
		unsigned	iface,
		void **	state,
		gnrc_ipv6_nib_ft_t *	fte
	)

Iterates over all forwarding table entries in the NIB.

Precondition

(state != NULL) && (fte != NULL)

Parameters

[in]	next_hop	Restrict iteration to entries to this next hop. NULL for any next hop. Can be used to build a source routing tree.
[in]	iface	Restrict iteration to entries on this interface. 0 for any interface.
[in,out]	state	Iteration state of the forwarding table. Must point to a NULL pointer to start iteration.
[out]	fte	The next forwarding table entry.

The iteration over all forwarding table entries in the NIB includes all entries added via gnrc_ipv6_nib_ft_add() and entries that are currently in the Destination Cache, in the Prefix List (only if they're on-link), and in the Default Router List.

Usage example:

#include "net/gnrc/ipv6/nib/ft.h"
 
int main(void) {
    void *state = NULL;
    gnrc_ipv6_nib_ft_t fte;
 
    puts("My neighbors:");
    while (gnrc_ipv6_nib_ft_iter(NULL, 0, &state, &fte)) {
        gnrc_ipv6_nib_ft_print(&fte);
    }
    return 0;
}

Note

The list may change during iteration.

Returns

true, if iteration can be continued.

false, if fte is the last neighbor cache entry in the NIB.

gnrc_ipv6_nib_ft_print()

void gnrc_ipv6_nib_ft_print

(

const gnrc_ipv6_nib_ft_t *

fte

)

Prints a forwarding table entry.

Precondition

fce != NULL

Parameters

[in]

fte

A forwarding table entry.