mctp: Add packet rx tests

Add a few tests for the initial packet ingress through
mctp_pkttype_receive function; mainly packet header sanity checks. Full
input routing checks will be added as a separate change.
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mctp/test/route-test.c

@@ -2,6 +2,8 @@
 
 #include <kunit/test.h>
 
+#include "utils.h"
+
 struct mctp_test_route {
 	struct mctp_route	rt;
 	struct sk_buff_head	pkts;
@@ -35,6 +37,7 @@ static struct mctp_test_route *mctp_route_test_alloc(void)
 }
 
 static struct mctp_test_route *mctp_test_create_route(struct net *net,
+						      struct mctp_dev *dev,
 						      mctp_eid_t eid,
 						      unsigned int mtu)
 {
@@ -48,7 +51,9 @@ static struct mctp_test_route *mctp_test_create_route(struct net *net,
 	rt->rt.max = eid;
 	rt->rt.mtu = mtu;
 	rt->rt.type = RTN_UNSPEC;
-	rt->rt.dev = NULL; /* somewhat illegal, but fine for current tests */
+	if (dev)
+		mctp_dev_hold(dev);
+	rt->rt.dev = dev;
 
 	list_add_rcu(&rt->rt.list, &net->mctp.routes);
 
@@ -65,6 +70,8 @@ static void mctp_test_route_destroy(struct kunit *test,
 	rtnl_unlock();
 
 	skb_queue_purge(&rt->pkts);
+	if (rt->rt.dev)
+		mctp_dev_put(rt->rt.dev);
 
 	refs = refcount_read(&rt->rt.refs);
 	KUNIT_ASSERT_EQ_MSG(test, refs, 1, "route ref imbalance");
@@ -72,7 +79,7 @@ static void mctp_test_route_destroy(struct kunit *test,
 	kfree_rcu(&rt->rt, rcu);
 }
 
-static struct sk_buff *mctp_test_create_skb(struct mctp_hdr *hdr,
+static struct sk_buff *mctp_test_create_skb(const struct mctp_hdr *hdr,
 					    unsigned int data_len)
 {
 	size_t hdr_len = sizeof(*hdr);
@@ -120,7 +127,7 @@ static void mctp_test_fragment(struct kunit *test)
 	skb = mctp_test_create_skb(&hdr, msgsize);
 	KUNIT_ASSERT_TRUE(test, skb);
 
-	rt = mctp_test_create_route(&init_net, 10, mtu);
+	rt = mctp_test_create_route(&init_net, NULL, 10, mtu);
 	KUNIT_ASSERT_TRUE(test, rt);
 
 	/* The refcount would usually be incremented as part of a route lookup,
@@ -204,8 +211,62 @@ static void mctp_frag_test_to_desc(const struct mctp_frag_test *t, char *desc)
 
 KUNIT_ARRAY_PARAM(mctp_frag, mctp_frag_tests, mctp_frag_test_to_desc);
 
+struct mctp_rx_input_test {
+	struct mctp_hdr hdr;
+	bool input;
+};
+
+static void mctp_test_rx_input(struct kunit *test)
+{
+	const struct mctp_rx_input_test *params;
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct sk_buff *skb;
+
+	params = test->param_value;
+
+	dev = mctp_test_create_dev();
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev);
+
+	rt = mctp_test_create_route(&init_net, dev->mdev, 8, 68);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, rt);
+
+	skb = mctp_test_create_skb(&params->hdr, 1);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, skb);
+
+	__mctp_cb(skb);
+
+	mctp_pkttype_receive(skb, dev->ndev, &mctp_packet_type, NULL);
+
+	KUNIT_EXPECT_EQ(test, !!rt->pkts.qlen, params->input);
+
+	mctp_test_route_destroy(test, rt);
+	mctp_test_destroy_dev(dev);
+}
+
+#define RX_HDR(_ver, _src, _dest, _fst) \
+	{ .ver = _ver, .src = _src, .dest = _dest, .flags_seq_tag = _fst }
+
+/* we have a route for EID 8 only */
+static const struct mctp_rx_input_test mctp_rx_input_tests[] = {
+	{ .hdr = RX_HDR(1, 10, 8, 0), .input = true },
+	{ .hdr = RX_HDR(1, 10, 9, 0), .input = false }, /* no input route */
+	{ .hdr = RX_HDR(2, 10, 8, 0), .input = false }, /* invalid version */
+};
+
+static void mctp_rx_input_test_to_desc(const struct mctp_rx_input_test *t,
+				       char *desc)
+{
+	sprintf(desc, "{%x,%x,%x,%x}", t->hdr.ver, t->hdr.src, t->hdr.dest,
+		t->hdr.flags_seq_tag);
+}
+
+KUNIT_ARRAY_PARAM(mctp_rx_input, mctp_rx_input_tests,
+		  mctp_rx_input_test_to_desc);
+
 static struct kunit_case mctp_test_cases[] = {
 	KUNIT_CASE_PARAM(mctp_test_fragment, mctp_frag_gen_params),
+	KUNIT_CASE_PARAM(mctp_test_rx_input, mctp_rx_input_gen_params),
 	{}
 };