[NETFILTER]: Add ctnetlink subsystem
Add ctnetlink subsystem for userspace-access to ip_conntrack table.
This allows reading and updating of existing entries, as well as
creating new ones (and new expect's) via nfnetlink.
Please note the 'strange' byte order: nfattr (tag+length) are in host
byte order, while the payload is always guaranteed to be in network
byte order. This allows a simple userspace process to encapsulate netlink
messages into arch-independent udp packets by just processing/swapping the
headers and not knowing anything about the actual payload.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index 710acd7..b0ed579 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -121,6 +121,7 @@
nfa->nfa_type = attrtype;
nfa->nfa_len = size;
memcpy(NFA_DATA(nfa), data, attrlen);
+ memset(NFA_DATA(nfa) + attrlen, 0, NFA_ALIGN(size) - size);
}
int nfattr_parse(struct nfattr *tb[], int maxattr, struct nfattr *nfa, int len)