bpf: sockmap, more BPF_SK_SKB_STREAM_VERDICT tests

Add BPF_SK_SKB_STREAM_VERDICT tests for ingress hook. While
we do this also bring stream tests in-line with MSG based
testing.

A map for skb options is added for userland to push options
at BPF programs.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

samples/sockmap/sockmap_kern.c

@@ -85,6 +85,12 @@ struct bpf_map_def SEC("maps") sock_redir_flags = {
 	.max_entries = 1
 };
 
+struct bpf_map_def SEC("maps") sock_skb_opts = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(int),
+	.value_size = sizeof(int),
+	.max_entries = 1
+};
 
 SEC("sk_skb1")
 int bpf_prog1(struct __sk_buff *skb)
@@ -97,15 +103,24 @@ int bpf_prog2(struct __sk_buff *skb)
 {
 	__u32 lport = skb->local_port;
 	__u32 rport = skb->remote_port;
-	int ret = 0;
+	int len, *f, ret, zero = 0;
+	__u64 flags = 0;
 
 	if (lport == 10000)
 		ret = 10;
 	else
 		ret = 1;
 
-	bpf_printk("sockmap: %d -> %d @ %d\n", lport, bpf_ntohl(rport), ret);
-	return bpf_sk_redirect_map(skb, &sock_map, ret, 0);
+	len = (__u32)skb->data_end - (__u32)skb->data;
+	f = bpf_map_lookup_elem(&sock_skb_opts, &zero);
+	if (f && *f) {
+		ret = 3;
+		flags = *f;
+	}
+
+	bpf_printk("sk_skb2: redirect(%iB) flags=%i\n",
+		   len, flags);
+	return bpf_sk_redirect_map(skb, &sock_map, ret, flags);
 }
 
 SEC("sockops")

samples/sockmap/sockmap_test.sh

 #Test a bunch of positive cases to verify basic functionality
-for prog in "--txmsg_redir --txmsg_ingress" "--txmsg" "--txmsg_redir" "--txmsg_redir --txmsg_ingress" "--txmsg_drop"; do
+for prog in  "--txmsg_redir --txmsg_skb" "--txmsg_redir --txmsg_ingress" "--txmsg" "--txmsg_redir" "--txmsg_redir --txmsg_ingress" "--txmsg_drop"; do
 for t in "sendmsg" "sendpage"; do
 for r in 1 10 100; do
 	for i in 1 10 100; do
@@ -109,6 +109,15 @@ for t in "sendmsg" "sendpage"; do
 	sleep 2
 done
 
+prog="--txmsg_redir --txmsg_apply 1 --txmsg_skb"
+
+for t in "sendmsg" "sendpage"; do
+	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
+	echo $TEST
+	$TEST
+	sleep 2
+done
+
 
 # Test apply and redirect with larger value than send
 r=1
@@ -132,6 +141,15 @@ for t in "sendmsg" "sendpage"; do
 	sleep 2
 done
 
+prog="--txmsg_redir --txmsg_apply 2048 --txmsg_skb"
+
+for t in "sendmsg" "sendpage"; do
+	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
+	echo $TEST
+	$TEST
+	sleep 2
+done
+
 
 # Test apply and redirect with apply that never reaches limit
 r=1024

samples/sockmap/sockmap_user.c

@@ -65,6 +65,7 @@ int txmsg_cork;
 int txmsg_start;
 int txmsg_end;
 int txmsg_ingress;
+int txmsg_skb;
 
 static const struct option long_options[] = {
 	{"help",	no_argument,		NULL, 'h' },
@@ -85,6 +86,7 @@ static const struct option long_options[] = {
 	{"txmsg_start", required_argument,	NULL, 's'},
 	{"txmsg_end",	required_argument,	NULL, 'e'},
 	{"txmsg_ingress", no_argument,		&txmsg_ingress, 1 },
+	{"txmsg_skb", no_argument,		&txmsg_skb, 1 },
 	{0, 0, NULL, 0 }
 };
 
@@ -828,6 +830,27 @@ int main(int argc, char **argv)
 					err, strerror(errno));
 			}
 		}
+
+		if (txmsg_skb) {
+			int skb_fd = (test == SENDMSG || test == SENDPAGE) ? p2 : p1;
+			int ingress = BPF_F_INGRESS;
+
+			i = 0;
+			err = bpf_map_update_elem(map_fd[7], &i, &ingress, BPF_ANY);
+			if (err) {
+				fprintf(stderr,
+					"ERROR: bpf_map_update_elem (txmsg_ingress): %d (%s)\n",
+					err, strerror(errno));
+			}
+
+			i = 3;
+			err = bpf_map_update_elem(map_fd[0], &i, &skb_fd, BPF_ANY);
+			if (err) {
+				fprintf(stderr,
+					"ERROR: bpf_map_update_elem (c1 sockmap): %d (%s)\n",
+					err, strerror(errno));
+			}
+		}
 	}
 
 	if (txmsg_drop)