libnl  1.1
Addresses
Routing Netlink

Allocation/Freeing

struct rtnl_addr * rtnl_addr_alloc (void)
void rtnl_addr_put (struct rtnl_addr *addr)

Cache Management

struct nl_cache * rtnl_addr_alloc_cache (struct nl_handle *handle)

Addition

struct nl_msg * rtnl_addr_build_add_request (struct rtnl_addr *addr, int flags)
 Build netlink request message to request addition of new address.
int rtnl_addr_add (struct nl_handle *handle, struct rtnl_addr *addr, int flags)
 Request addition of new address.

Deletion

struct nl_msg * rtnl_addr_build_delete_request (struct rtnl_addr *addr, int flags)
 Build a netlink request message to request deletion of an address.
int rtnl_addr_delete (struct nl_handle *handle, struct rtnl_addr *addr, int flags)
 Request deletion of an address.

Attributes

void rtnl_addr_set_label (struct rtnl_addr *addr, const char *label)
char * rtnl_addr_get_label (struct rtnl_addr *addr)
void rtnl_addr_set_ifindex (struct rtnl_addr *addr, int ifindex)
int rtnl_addr_get_ifindex (struct rtnl_addr *addr)
void rtnl_addr_set_family (struct rtnl_addr *addr, int family)
int rtnl_addr_get_family (struct rtnl_addr *addr)
void rtnl_addr_set_prefixlen (struct rtnl_addr *addr, int prefix)
int rtnl_addr_get_prefixlen (struct rtnl_addr *addr)
void rtnl_addr_set_scope (struct rtnl_addr *addr, int scope)
int rtnl_addr_get_scope (struct rtnl_addr *addr)
void rtnl_addr_set_flags (struct rtnl_addr *addr, unsigned int flags)
void rtnl_addr_unset_flags (struct rtnl_addr *addr, unsigned int flags)
unsigned int rtnl_addr_get_flags (struct rtnl_addr *addr)
int rtnl_addr_set_local (struct rtnl_addr *addr, struct nl_addr *local)
struct nl_addr * rtnl_addr_get_local (struct rtnl_addr *addr)
int rtnl_addr_set_peer (struct rtnl_addr *addr, struct nl_addr *peer)
struct nl_addr * rtnl_addr_get_peer (struct rtnl_addr *addr)
int rtnl_addr_set_broadcast (struct rtnl_addr *addr, struct nl_addr *bcast)
struct nl_addr * rtnl_addr_get_broadcast (struct rtnl_addr *addr)
int rtnl_addr_set_anycast (struct rtnl_addr *addr, struct nl_addr *anycast)
struct nl_addr * rtnl_addr_get_anycast (struct rtnl_addr *addr)
int rtnl_addr_set_multicast (struct rtnl_addr *addr, struct nl_addr *multicast)
struct nl_addr * rtnl_addr_get_multicast (struct rtnl_addr *addr)

Flags Translations

char * rtnl_addr_flags2str (int flags, char *buf, size_t size)
int rtnl_addr_str2flags (const char *name)

Detailed Description

Note
The maximum size of an address label is IFNAMSIZ.
The address may not contain a prefix length if the peer address has been specified already.
1) Address Addition
// Allocate an empty address object to be filled out with the attributes
// of the new address.
struct rtnl_addr *addr = rtnl_addr_alloc();
// Fill out the mandatory attributes of the new address. Setting the
// local address will automatically set the address family and the
// prefix length to the correct values.
rtnl_addr_set_ifindex(addr, ifindex);
rtnl_addr_set_local(addr, local_addr);
// The label of the address can be specified, currently only supported
// by IPv4 and DECnet.
rtnl_addr_set_label(addr, "mylabel");
// The peer address can be specified if necessary, in either case a peer
// address will be sent to the kernel in order to fullfil the interface
// requirements. If none is set, it will equal the local address.
// Note: Real peer addresses are only supported by IPv4 for now.
rtnl_addr_set_peer(addr, peer_addr);
// In case you want to have the address have a scope other than global
// it may be overwritten using rtnl_addr_set_scope(). The scope currently
// cannot be set for IPv6 addresses.
rtnl_addr_set_scope(addr, rtnl_str2scope("site"));
// Broadcast and anycast address may be specified using the relevant
// functions, the address family will be verified if one of the other
// addresses has been set already. Currently only works for IPv4.
rtnl_addr_set_broadcast(addr, broadcast_addr);
rtnl_addr_set_anycast(addr, anycast_addr);
// Build the netlink message and send it to the kernel, the operation will
// block until the operation has been completed. Alternatively the required
// netlink message can be built using rtnl_addr_build_add_request() to be
// sent out using nl_send_auto_complete().
rtnl_addr_add(handle, addr, 0);
// Free the memory
rtnl_addr_put(addr);
2) Address Deletion
// Allocate an empty address object to be filled out with the attributes
// matching the address to be deleted. Alternatively a fully equipped
// address object out of a cache can be used instead.
struct rtnl_addr *addr = rtnl_addr_alloc();
// The only mandatory parameter besides the address family is the interface
// index the address is on, i.e. leaving out all other parameters will
// result in all addresses of the specified address family interface tuple
// to be deleted.
rtnl_addr_set_ifindex(addr, ifindex);
// Specyfing the address family manually is only required if neither the
// local nor peer address have been specified.
rtnl_addr_set_family(addr, AF_INET);
// Specyfing the local address is optional but the best choice to delete
// specific addresses.
rtnl_addr_set_local(addr, local_addr);
// The label of the address can be specified, currently only supported
// by IPv4 and DECnet.
rtnl_addr_set_label(addr, "mylabel");
// The peer address can be specified if necessary, in either case a peer
// address will be sent to the kernel in order to fullfil the interface
// requirements. If none is set, it will equal the local address.
// Note: Real peer addresses are only supported by IPv4 for now.
rtnl_addr_set_peer(addr, peer_addr);
// Build the netlink message and send it to the kernel, the operation will
// block until the operation has been completed. Alternatively the required
// netlink message can be built using rtnl_addr_build_delete_request()
// to be sent out using nl_send_auto_complete().
rtnl_addr_delete(handle, addr, 0);
// Free the memory
rtnl_addr_put(addr);

Function Documentation

struct nl_msg* rtnl_addr_build_add_request ( struct rtnl_addr *  addr,
int  flags 
)
read
Parameters
addrAddress object representing the new address.
flagsAdditional netlink message flags.

Builds a new netlink message requesting the addition of a new address. The netlink message header isn't fully equipped with all relevant fields and must thus be sent out via nl_send_auto_complete() or supplemented as needed.

Minimal required attributes:

  • interface index (rtnl_addr_set_ifindex())
  • local address (rtnl_addr_set_local())

The scope will default to universe except for loopback addresses in which case a host scope is used if not specified otherwise.

Note
Free the memory after usage using nlmsg_free().
Returns
Newly allocated netlink message or NULL if an error occured.

Definition at line 737 of file addr.c.

References NLM_F_CREATE.

Referenced by rtnl_addr_add().

int rtnl_addr_add ( struct nl_handle *  handle,
struct rtnl_addr *  addr,
int  flags 
)
Parameters
handleNetlink handle.
addrAddress object representing the new address.
flagsAdditional netlink message flags.

Builds a netlink message by calling rtnl_addr_build_add_request(), sends the request to the kernel and waits for the next ACK to be received and thus blocks until the request has been fullfilled.

See Also
rtnl_addr_build_add_request()
Returns
0 on sucess or a negative error if an error occured.

Definition at line 765 of file addr.c.

References nl_send_auto_complete(), nl_wait_for_ack(), nlmsg_free(), and rtnl_addr_build_add_request().

struct nl_msg* rtnl_addr_build_delete_request ( struct rtnl_addr *  addr,
int  flags 
)
read
Parameters
addrAddress object to be deleteted.
flagsAdditional netlink message flags.

Builds a new netlink message requesting a deletion of an address. The netlink message header isn't fully equipped with all relevant fields and must thus be sent out via nl_send_auto_complete() or supplemented as needed.

Minimal required attributes:

  • interface index (rtnl_addr_set_ifindex())
  • address family (rtnl_addr_set_family())

Optional attributes:

  • local address (rtnl_addr_set_local())
  • label (rtnl_addr_set_label(), IPv4/DECnet only)
  • peer address (rtnl_addr_set_peer(), IPv4 only)
Note
Free the memory after usage using nlmsg_free().
Returns
Newly allocated netlink message or NULL if an error occured.

Definition at line 811 of file addr.c.

Referenced by rtnl_addr_delete().

int rtnl_addr_delete ( struct nl_handle *  handle,
struct rtnl_addr *  addr,
int  flags 
)
Parameters
handleNetlink handle.
addrAddress object to be deleted.
flagsAdditional netlink message flags.

Builds a netlink message by calling rtnl_addr_build_delete_request(), sends the request to the kernel and waits for the next ACK to be received and thus blocks until the request has been fullfilled.

See Also
rtnl_addr_build_delete_request();
Returns
0 on sucess or a negative error if an error occured.

Definition at line 838 of file addr.c.

References nl_send_auto_complete(), nl_wait_for_ack(), nlmsg_free(), and rtnl_addr_build_delete_request().