bpf: sockmap, add BPF_F_INGRESS tests

Add a set of tests to verify ingress flag in redirect helpers
works correctly with various msg sizes.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

samples/sockmap/sockmap_kern.c

@@ -54,7 +54,7 @@ struct bpf_map_def SEC("maps") sock_map_redir = {
 	.type = BPF_MAP_TYPE_SOCKMAP,
 	.key_size = sizeof(int),
 	.value_size = sizeof(int),
-	.max_entries = 1,
+	.max_entries = 20,
 };
 
 struct bpf_map_def SEC("maps") sock_apply_bytes = {
@@ -78,6 +78,13 @@ struct bpf_map_def SEC("maps") sock_pull_bytes = {
 	.max_entries = 2
 };
 
+struct bpf_map_def SEC("maps") sock_redir_flags = {
+	.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)
@@ -197,8 +204,9 @@ int bpf_prog5(struct sk_msg_md *msg)
 SEC("sk_msg3")
 int bpf_prog6(struct sk_msg_md *msg)
 {
-	int *bytes, zero = 0, one = 1;
-	int *start, *end;
+	int *bytes, zero = 0, one = 1, key = 0;
+	int *start, *end, *f;
+	__u64 flags = 0;
 
 	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
 	if (bytes)
@@ -210,15 +218,22 @@ int bpf_prog6(struct sk_msg_md *msg)
 	end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
 	if (start && end)
 		bpf_msg_pull_data(msg, *start, *end, 0);
-	return bpf_msg_redirect_map(msg, &sock_map_redir, zero, 0);
+	f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
+	if (f && *f) {
+		key = 2;
+		flags = *f;
+	}
+	return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
 }
 
 SEC("sk_msg4")
 int bpf_prog7(struct sk_msg_md *msg)
 {
-	int err1 = 0, err2 = 0, zero = 0, one = 1;
-	int *bytes, *start, *end, len1, len2;
+	int err1 = 0, err2 = 0, zero = 0, one = 1, key = 0;
+	int *f, *bytes, *start, *end, len1, len2;
+	__u64 flags = 0;
 
+		int err;
 	bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
 	if (bytes)
 		err1 = bpf_msg_apply_bytes(msg, *bytes);
@@ -229,7 +244,6 @@ int bpf_prog7(struct sk_msg_md *msg)
 	start = bpf_map_lookup_elem(&sock_pull_bytes, &zero);
 	end = bpf_map_lookup_elem(&sock_pull_bytes, &one);
 	if (start && end) {
-		int err;
 
 		bpf_printk("sk_msg2: pull(%i:%i)\n",
 			   start ? *start : 0, end ? *end : 0);
@@ -241,9 +255,16 @@ int bpf_prog7(struct sk_msg_md *msg)
 		bpf_printk("sk_msg2: length update %i->%i\n",
 			   len1, len2);
 	}
-	bpf_printk("sk_msg3: redirect(%iB) err1=%i err2=%i\n",
-		   len1, err1, err2);
-	return bpf_msg_redirect_map(msg, &sock_map_redir, zero, 0);
+	f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
+	if (f && *f) {
+		key = 2;
+		flags = *f;
+	}
+	bpf_printk("sk_msg3: redirect(%iB) flags=%i err=%i\n",
+		   len1, flags, err1 ? err1 : err2);
+	err = bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
+	bpf_printk("sk_msg3: err %i\n", err);
+	return err;
 }
 
 SEC("sk_msg5")

samples/sockmap/sockmap_test.sh

 #Test a bunch of positive cases to verify basic functionality
-for prog in "--txmsg" "--txmsg_redir" "--txmsg_drop"; do
+for prog in "--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
@@ -100,6 +100,16 @@ for t in "sendmsg" "sendpage"; do
 	sleep 2
 done
 
+prog="--txmsg_redir --txmsg_apply 1 --txmsg_ingress"
+
+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
 i=8
@@ -113,6 +123,16 @@ for t in "sendmsg" "sendpage"; do
 	sleep 2
 done
 
+prog="--txmsg_redir --txmsg_apply 2048 --txmsg_ingress"
+
+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
 i=1

samples/sockmap/sockmap_user.c

@@ -64,6 +64,7 @@ int txmsg_apply;
 int txmsg_cork;
 int txmsg_start;
 int txmsg_end;
+int txmsg_ingress;
 
 static const struct option long_options[] = {
 	{"help",	no_argument,		NULL, 'h' },
@@ -83,6 +84,7 @@ static const struct option long_options[] = {
 	{"txmsg_cork",	required_argument,	NULL, 'k'},
 	{"txmsg_start", required_argument,	NULL, 's'},
 	{"txmsg_end",	required_argument,	NULL, 'e'},
+	{"txmsg_ingress", no_argument,		&txmsg_ingress, 1 },
 	{0, 0, NULL, 0 }
 };
 
@@ -793,6 +795,39 @@ int main(int argc, char **argv)
 				return err;
 			}
 		}
+
+		if (txmsg_ingress) {
+			int in = BPF_F_INGRESS;
+
+			i = 0;
+			err = bpf_map_update_elem(map_fd[6], &i, &in, BPF_ANY);
+			if (err) {
+				fprintf(stderr,
+					"ERROR: bpf_map_update_elem (txmsg_ingress): %d (%s)\n",
+					err, strerror(errno));
+			}
+			i = 1;
+			err = bpf_map_update_elem(map_fd[1], &i, &p1, BPF_ANY);
+			if (err) {
+				fprintf(stderr,
+					"ERROR: bpf_map_update_elem (p1 txmsg): %d (%s)\n",
+					err, strerror(errno));
+			}
+			err = bpf_map_update_elem(map_fd[2], &i, &p1, BPF_ANY);
+			if (err) {
+				fprintf(stderr,
+					"ERROR: bpf_map_update_elem (p1 redir): %d (%s)\n",
+					err, strerror(errno));
+			}
+
+			i = 2;
+			err = bpf_map_update_elem(map_fd[2], &i, &p2, BPF_ANY);
+			if (err) {
+				fprintf(stderr,
+					"ERROR: bpf_map_update_elem (p2 txmsg): %d (%s)\n",
+					err, strerror(errno));
+			}
+		}
 	}
 
 	if (txmsg_drop)