[NETLINK]: fib_lookup() via netlink

Below is a more generic patch to do fib_lookup via netlink. For others 
we should say that we discussed this as a way to verify route selection.
It's also possible there are others uses for this.

In short the fist half of struct fib_result_nl is filled in by caller 
and netlink call fills in the other half and returns it.

In case anyone is interested there is a corresponding user app to compare 
the full routing table this was used to test implementation of the LC-trie. 

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Robert Olsson 2005-06-20 13:36:39 -07:00 committed by David S. Miller
parent f6e276ee67
commit 246955fe4c
3 changed files with 70 additions and 0 deletions

View File

@ -14,6 +14,7 @@
#define NETLINK_SELINUX 7 /* SELinux event notifications */
#define NETLINK_ARPD 8
#define NETLINK_AUDIT 9 /* auditing */
#define NETLINK_FIB_LOOKUP 10
#define NETLINK_ROUTE6 11 /* af_inet6 route comm channel */
#define NETLINK_IP6_FW 13
#define NETLINK_DNRTMSG 14 /* DECnet routing messages */

View File

@ -109,6 +109,20 @@ struct fib_result {
#endif
};
struct fib_result_nl {
u32 fl_addr; /* To be looked up*/
u32 fl_fwmark;
unsigned char fl_tos;
unsigned char fl_scope;
unsigned char tb_id_in;
unsigned char tb_id; /* Results */
unsigned char prefixlen;
unsigned char nh_sel;
unsigned char type;
unsigned char scope;
int err;
};
#ifdef CONFIG_IP_ROUTE_MULTIPATH

View File

@ -516,6 +516,60 @@ static void fib_del_ifaddr(struct in_ifaddr *ifa)
#undef BRD1_OK
}
static void nl_fib_lookup(struct fib_result_nl *frn, struct fib_table *tb )
{
struct fib_result res;
struct flowi fl = { .nl_u = { .ip4_u = { .daddr = frn->fl_addr,
.fwmark = frn->fl_fwmark,
.tos = frn->fl_tos,
.scope = frn->fl_scope } } };
if (tb) {
local_bh_disable();
frn->tb_id = tb->tb_id;
frn->err = tb->tb_lookup(tb, &fl, &res);
if (!frn->err) {
frn->prefixlen = res.prefixlen;
frn->nh_sel = res.nh_sel;
frn->type = res.type;
frn->scope = res.scope;
}
local_bh_enable();
}
}
static void nl_fib_input(struct sock *sk, int len)
{
struct sk_buff *skb = NULL;
struct nlmsghdr *nlh = NULL;
struct fib_result_nl *frn;
int err;
u32 pid;
struct fib_table *tb;
skb = skb_recv_datagram(sk, 0, 0, &err);
nlh = (struct nlmsghdr *)skb->data;
frn = (struct fib_result_nl *) NLMSG_DATA(nlh);
tb = fib_get_table(frn->tb_id_in);
nl_fib_lookup(frn, tb);
pid = nlh->nlmsg_pid; /*pid of sending process */
NETLINK_CB(skb).groups = 0; /* not in mcast group */
NETLINK_CB(skb).pid = 0; /* from kernel */
NETLINK_CB(skb).dst_pid = pid;
NETLINK_CB(skb).dst_groups = 0; /* unicast */
netlink_unicast(sk, skb, pid, MSG_DONTWAIT);
}
static void nl_fib_lookup_init(void)
{
netlink_kernel_create(NETLINK_FIB_LOOKUP, nl_fib_input);
}
static void fib_disable_ip(struct net_device *dev, int force)
{
if (fib_sync_down(0, dev, force))
@ -604,6 +658,7 @@ void __init ip_fib_init(void)
register_netdevice_notifier(&fib_netdev_notifier);
register_inetaddr_notifier(&fib_inetaddr_notifier);
nl_fib_lookup_init();
}
EXPORT_SYMBOL(inet_addr_type);