FIB Lookup

Modules
	Request
Allocation/Freeing
struct flnl_result *	flnl_result_alloc (void)
void	flnl_result_put (struct flnl_result *res)
Cache Management
struct nl_cache *	flnl_result_alloc_cache (void)
	Allocate lookup result cache.
Lookup
struct nl_msg *	flnl_lookup_build_request (struct flnl_request *req, int flags)
	Builds a netlink request message to do a lookup.
int	flnl_lookup (struct nl_handle *handle, struct flnl_request *req, struct nl_cache *cache)
	Perform FIB Lookup.
Attribute Access
int	flnl_result_get_table_id (struct flnl_result *res)
int	flnl_result_get_prefixlen (struct flnl_result *res)
int	flnl_result_get_nexthop_sel (struct flnl_result *res)
int	flnl_result_get_type (struct flnl_result *res)
int	flnl_result_get_scope (struct flnl_result *res)
int	flnl_result_get_error (struct flnl_result *res)

---

Function Documentation

struct nl_cache* flnl_result_alloc_cache

(

void

)

[read]

Allocates a new lookup result cache and initializes it properly.

Note:

Free the memory after usage using nl_cache_destroy_and_free().

Returns:

Newly allocated cache or NULL if an error occured.

Definition at line 183 of file lookup.c.

References nl_cache_alloc().

{
        return nl_cache_alloc(&fib_lookup_ops);
}

struct nl_msg* flnl_lookup_build_request	(	struct flnl_request *	req,
		int	flags
	)		[read]

Parameters:

req	Requested match.
flags	additional netlink message flags

Builds a new netlink message requesting a change of link attributes. The netlink message header isn't fully equipped with all relevant fields and must be sent out via nl_send_auto_complete() or supplemented as needed. old must point to a link currently configured in the kernel and tmpl must contain the attributes to be changed set via rtnl_link_set_* functions.

Returns:

New netlink message

Note:

Not all attributes can be changed, see Changeable Attributes for more details.

Definition at line 212 of file lookup.c.

References nl_addr_get_binary_addr(), nlmsg_alloc_simple(), nlmsg_append(), and nlmsg_free().

Referenced by flnl_lookup().

{
        struct nl_msg *msg;
        struct nl_addr *addr;
        uint64_t fwmark;
        int tos, scope, table;
        struct fib_result_nl fr = {0};

        fwmark = flnl_request_get_fwmark(req);
        tos = flnl_request_get_tos(req);
        scope = flnl_request_get_scope(req);
        table = flnl_request_get_table(req);

        fr.fl_fwmark = fwmark != UINT_LEAST64_MAX ? fwmark : 0;
        fr.fl_tos = tos >= 0 ? tos : 0;
        fr.fl_scope = scope >= 0 ? scope : RT_SCOPE_UNIVERSE;
        fr.tb_id_in = table >= 0 ? table : RT_TABLE_UNSPEC;

        addr = flnl_request_get_addr(req);
        if (!addr) {
                nl_error(EINVAL, "Request must specify the address");
                return NULL;
        }

        fr.fl_addr = *(uint32_t *) nl_addr_get_binary_addr(addr);

        msg = nlmsg_alloc_simple(0, flags);
        if (!msg)
                goto errout;

        if (nlmsg_append(msg, &fr, sizeof(fr), NLMSG_ALIGNTO) < 0)
                goto errout;

        return msg;

errout:
        nlmsg_free(msg);
        return NULL;
}

int flnl_lookup	(	struct nl_handle *	handle,
		struct flnl_request *	req,
		struct nl_cache *	cache
	)

Parameters:

handle	Netlink handle.
req	Lookup request object.
cache	Cache for result.

Builds a netlink message to request a FIB lookup, waits for the reply and adds the result to the specified cache.

Returns:

0 on success or a negative error code.

Definition at line 263 of file lookup.c.

References flnl_lookup_build_request(), nl_cache_pickup(), nl_send_auto_complete(), and nlmsg_free().

{
        struct nl_msg *msg;
        int err;

        msg = flnl_lookup_build_request(req, 0);
        if (!msg)
                return nl_errno(ENOMEM);

        err = nl_send_auto_complete(handle, msg);
        nlmsg_free(msg);
        if (err < 0)
                return err;

        return nl_cache_pickup(handle, cache);
}