Link layer address filter

Module for filtering (black- or white-listing) link layer addresses.

This module is used as a base for filtering link layer addresses. It allows to be (globally) configured in either blacklist or in whitelist mode. This configuration is done via RIOTs module system, for whitelist mode simply include the module L2FILTER_WHITELIST, for blacklist mode include L2FILTER_BLACKLIST.

The actual memory for the filter lists should be allocated for every network device. This is done centrally in netdev_t type.

int l2filter_add(l2filter_t * list, const void * addr, msp430_types.h::size_t addr_len)

Add an entry to a devices filter list.

Parameters

list:pointer to the filter list
addr:address to be added to list
addr_len:size of addr [in byte]

Return values

  • 0 on success
  • -ENOMEM if no empty slot left in list
int l2filter_rm(l2filter_t * list, const void * addr, msp430_types.h::size_t addr_len)

Remove an entry from the given filter list.

Parameters

list:pointer to the filter list
addr:address to remove from the list
addr_len:length of addr [in byte]

Return values

  • 0 on success
  • -ENOENT if addr was not found in list
bool l2filter_pass(const l2filter_t * list, const void * addr, msp430_types.h::size_t addr_len)

Check if the given address passes the set filters.

Independent if the l2filter module is used in blacklist or in whitelist mode, this function returns whether the given address passes the filter. In whitelist mode, this means that the given address has to be in the list, in blacklist mode this means that the given address is not in the list.

Parameters

list:list with black-/whitelisted addresses
addr:address to check against the entries in list
addr_len:length of addr [in byte]

Return values

  • in whitelist mode: true if addr is in list
  • in whitelist mode: false if addr is not in list
  • in blacklist mode: true if addr is not in list
  • in blacklist mode: false if addr is in list
L2FILTER_ADDR_MAXLEN

Maximal length of addresses that can be stored in the filter list. 

1
(8U)
L2FILTER_LISTSIZE

Number of slots in each filter list (filter entries per device) 

1
(8U)
struct l2filter_t

Filter list entries.

The filter list supports address entries with differing length. This is useful e.g. for IEEE802.15.4, where the list can store short and long addresses at the same time.

uint8_t addr()

link layer address

msp430_types.h::size_t addr_len

address length in byte