From 0c5c2d3089068d4aa378f7a40d2b5ad9d4f52ce8 Mon Sep 17 00:00:00 2001 From: Eric Biederman Date: Wed, 4 Mar 2009 00:03:08 -0800 Subject: [PATCH] neigh: Allow for user space users of the neighbour table Currently it is possible to do just about everything with the arp table from user space except treat an entry like you are using it. To that end implement and a flag NTF_USE that when set in a netwlink update request treats the neighbour table entry like the kernel does on the output path. This allows user space applications to share the kernel's arp cache. Signed-off-by: Eric Biederman Signed-off-by: David S. Miller --- include/linux/neighbour.h | 1 + net/core/neighbour.c | 6 +++++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/include/linux/neighbour.h b/include/linux/neighbour.h index 8730d5dae1bc..12c9de138451 100644 --- a/include/linux/neighbour.h +++ b/include/linux/neighbour.h @@ -31,6 +31,7 @@ enum * Neighbor Cache Entry Flags */ +#define NTF_USE 0x01 #define NTF_PROXY 0x08 /* == ATF_PUBL */ #define NTF_ROUTER 0x80 diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 417b6d739fb7..a1cbce7fdae5 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -1654,7 +1654,11 @@ static int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) flags &= ~NEIGH_UPDATE_F_OVERRIDE; } - err = neigh_update(neigh, lladdr, ndm->ndm_state, flags); + if (ndm->ndm_flags & NTF_USE) { + neigh_event_send(neigh, NULL); + err = 0; + } else + err = neigh_update(neigh, lladdr, ndm->ndm_state, flags); neigh_release(neigh); goto out_dev_put; } -- 2.39.5