From 246955fe4c38bd706ae30e37c64892c94213775d Mon Sep 17 00:00:00 2001 From: Robert Olsson Date: Mon, 20 Jun 2005 13:36:39 -0700 Subject: [PATCH] [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 --- include/linux/netlink.h | 1 + include/net/ip_fib.h | 14 +++++++++++ net/ipv4/fib_frontend.c | 55 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 70 insertions(+) diff --git a/include/linux/netlink.h b/include/linux/netlink.h index e38407a23d..561d4dc758 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -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 */ diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index e5a5f6b62f..a4208a336a 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -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 diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 563e7d6127..cd8e45ab95 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -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); -- 2.39.5