[NETFILTER]: nf_conntrack: add helper function for expectation initialization

Expectation address masks need to be differently initialized depending
on the address family, create helper function to avoid cluttering up
the code too much.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 68 insertions, 0 deletions

diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
index aa5903e4da1..68623ae778c 100644
--- a/net/netfilter/nf_conntrack_expect.c
+++ b/net/netfilter/nf_conntrack_expect.c
@@ -196,6 +196,74 @@ struct nf_conntrack_expect *nf_conntrack_expect_alloc(struct nf_conn *me)
 	return new;
 }
 
+void nf_conntrack_expect_init(struct nf_conntrack_expect *exp, int family,
+			      union nf_conntrack_address *saddr,
+			      union nf_conntrack_address *daddr,
+			      u_int8_t proto, __be16 *src, __be16 *dst)
+{
+	int len;
+
+	if (family == AF_INET)
+		len = 4;
+	else
+		len = 16;
+
+	exp->flags = 0;
+	exp->expectfn = NULL;
+	exp->helper = NULL;
+	exp->tuple.src.l3num = family;
+	exp->tuple.dst.protonum = proto;
+	exp->mask.src.l3num = 0xFFFF;
+	exp->mask.dst.protonum = 0xFF;
+
+	if (saddr) {
+		memcpy(&exp->tuple.src.u3, saddr, len);
+		if (sizeof(exp->tuple.src.u3) > len)
+			/* address needs to be cleared for nf_ct_tuple_equal */
+			memset((void *)&exp->tuple.src.u3 + len, 0x00,
+			       sizeof(exp->tuple.src.u3) - len);
+		memset(&exp->mask.src.u3, 0xFF, len);
+		if (sizeof(exp->mask.src.u3) > len)
+			memset((void *)&exp->mask.src.u3 + len, 0x00,
+			       sizeof(exp->mask.src.u3) - len);
+	} else {
+		memset(&exp->tuple.src.u3, 0x00, sizeof(exp->tuple.src.u3));
+		memset(&exp->mask.src.u3, 0x00, sizeof(exp->mask.src.u3));
+	}
+
+	if (daddr) {
+		memcpy(&exp->tuple.dst.u3, daddr, len);
+		if (sizeof(exp->tuple.dst.u3) > len)
+			/* address needs to be cleared for nf_ct_tuple_equal */
+			memset((void *)&exp->tuple.dst.u3 + len, 0x00,
+			       sizeof(exp->tuple.dst.u3) - len);
+		memset(&exp->mask.dst.u3, 0xFF, len);
+		if (sizeof(exp->mask.dst.u3) > len)
+			memset((void *)&exp->mask.dst.u3 + len, 0x00,
+			       sizeof(exp->mask.dst.u3) - len);
+	} else {
+		memset(&exp->tuple.dst.u3, 0x00, sizeof(exp->tuple.dst.u3));
+		memset(&exp->mask.dst.u3, 0x00, sizeof(exp->mask.dst.u3));
+	}
+
+	if (src) {
+		exp->tuple.src.u.all = (__force u16)*src;
+		exp->mask.src.u.all = 0xFFFF;
+	} else {
+		exp->tuple.src.u.all = 0;
+		exp->mask.src.u.all = 0;
+	}
+
+	if (dst) {
+		exp->tuple.dst.u.all = (__force u16)*dst;
+		exp->mask.dst.u.all = 0xFFFF;
+	} else {
+		exp->tuple.dst.u.all = 0;
+		exp->mask.dst.u.all = 0;
+	}
+}
+EXPORT_SYMBOL_GPL(nf_conntrack_expect_init);
+
 void nf_conntrack_expect_put(struct nf_conntrack_expect *exp)
 {
 	if (atomic_dec_and_test(&exp->use))