bpf: test BPF_MAP_TYPE_REUSEPORT_SOCKARRAY

This patch adds tests for the new BPF_MAP_TYPE_REUSEPORT_SOCKARRAY.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/lib/bpf/libbpf.c

@@ -1501,6 +1501,7 @@ static bool bpf_prog_type__needs_kver(enum bpf_prog_type type)
 	case BPF_PROG_TYPE_SK_MSG:
 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
 	case BPF_PROG_TYPE_LIRC_MODE2:
+	case BPF_PROG_TYPE_SK_REUSEPORT:
 		return false;
 	case BPF_PROG_TYPE_UNSPEC:
 	case BPF_PROG_TYPE_KPROBE:

tools/testing/selftests/bpf/test_maps.c

@@ -17,7 +17,8 @@
 #include <stdlib.h>
 
 #include <sys/wait.h>
-
+#include <sys/socket.h>
+#include <netinet/in.h>
 #include <linux/bpf.h>
 
 #include <bpf/bpf.h>
@@ -26,8 +27,21 @@
 #include "bpf_util.h"
 #include "bpf_rlimit.h"
 
+#ifndef ENOTSUPP
+#define ENOTSUPP 524
+#endif
+
 static int map_flags;
 
+#define CHECK(condition, tag, format...) ({				\
+	int __ret = !!(condition);					\
+	if (__ret) {							\
+		printf("%s(%d):FAIL:%s ", __func__, __LINE__, tag);	\
+		printf(format);						\
+		exit(-1);						\
+	}								\
+})
+
 static void test_hashmap(int task, void *data)
 {
 	long long key, next_key, first_key, value;
@@ -1150,6 +1164,250 @@ static void test_map_wronly(void)
 	assert(bpf_map_get_next_key(fd, &key, &value) == -1 && errno == EPERM);
 }
 
+static void prepare_reuseport_grp(int type, int map_fd,
+				  __s64 *fds64, __u64 *sk_cookies,
+				  unsigned int n)
+{
+	socklen_t optlen, addrlen;
+	struct sockaddr_in6 s6;
+	const __u32 index0 = 0;
+	const int optval = 1;
+	unsigned int i;
+	u64 sk_cookie;
+	__s64 fd64;
+	int err;
+
+	s6.sin6_family = AF_INET6;
+	s6.sin6_addr = in6addr_any;
+	s6.sin6_port = 0;
+	addrlen = sizeof(s6);
+	optlen = sizeof(sk_cookie);
+
+	for (i = 0; i < n; i++) {
+		fd64 = socket(AF_INET6, type, 0);
+		CHECK(fd64 == -1, "socket()",
+		      "sock_type:%d fd64:%lld errno:%d\n",
+		      type, fd64, errno);
+
+		err = setsockopt(fd64, SOL_SOCKET, SO_REUSEPORT,
+				 &optval, sizeof(optval));
+		CHECK(err == -1, "setsockopt(SO_REUSEEPORT)",
+		      "err:%d errno:%d\n", err, errno);
+
+		/* reuseport_array does not allow unbound sk */
+		err = bpf_map_update_elem(map_fd, &index0, &fd64,
+					  BPF_ANY);
+		CHECK(err != -1 || errno != EINVAL,
+		      "reuseport array update unbound sk",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		err = bind(fd64, (struct sockaddr *)&s6, sizeof(s6));
+		CHECK(err == -1, "bind()",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		if (i == 0) {
+			err = getsockname(fd64, (struct sockaddr *)&s6,
+					  &addrlen);
+			CHECK(err == -1, "getsockname()",
+			      "sock_type:%d err:%d errno:%d\n",
+			      type, err, errno);
+		}
+
+		err = getsockopt(fd64, SOL_SOCKET, SO_COOKIE, &sk_cookie,
+				 &optlen);
+		CHECK(err == -1, "getsockopt(SO_COOKIE)",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		if (type == SOCK_STREAM) {
+			/*
+			 * reuseport_array does not allow
+			 * non-listening tcp sk.
+			 */
+			err = bpf_map_update_elem(map_fd, &index0, &fd64,
+						  BPF_ANY);
+			CHECK(err != -1 || errno != EINVAL,
+			      "reuseport array update non-listening sk",
+			      "sock_type:%d err:%d errno:%d\n",
+			      type, err, errno);
+			err = listen(fd64, 0);
+			CHECK(err == -1, "listen()",
+			      "sock_type:%d, err:%d errno:%d\n",
+			      type, err, errno);
+		}
+
+		fds64[i] = fd64;
+		sk_cookies[i] = sk_cookie;
+	}
+}
+
+static void test_reuseport_array(void)
+{
+#define REUSEPORT_FD_IDX(err, last) ({ (err) ? last : !last; })
+
+	const __u32 array_size = 4, index0 = 0, index3 = 3;
+	int types[2] = { SOCK_STREAM, SOCK_DGRAM }, type;
+	__u64 grpa_cookies[2], sk_cookie, map_cookie;
+	__s64 grpa_fds64[2] = { -1, -1 }, fd64 = -1;
+	const __u32 bad_index = array_size;
+	int map_fd, err, t, f;
+	__u32 fds_idx = 0;
+	int fd;
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
+				sizeof(__u32), sizeof(__u64), array_size, 0);
+	CHECK(map_fd == -1, "reuseport array create",
+	      "map_fd:%d, errno:%d\n", map_fd, errno);
+
+	/* Test lookup/update/delete with invalid index */
+	err = bpf_map_delete_elem(map_fd, &bad_index);
+	CHECK(err != -1 || errno != E2BIG, "reuseport array del >=max_entries",
+	      "err:%d errno:%d\n", err, errno);
+
+	err = bpf_map_update_elem(map_fd, &bad_index, &fd64, BPF_ANY);
+	CHECK(err != -1 || errno != E2BIG,
+	      "reuseport array update >=max_entries",
+	      "err:%d errno:%d\n", err, errno);
+
+	err = bpf_map_lookup_elem(map_fd, &bad_index, &map_cookie);
+	CHECK(err != -1 || errno != ENOENT,
+	      "reuseport array update >=max_entries",
+	      "err:%d errno:%d\n", err, errno);
+
+	/* Test lookup/delete non existence elem */
+	err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+	CHECK(err != -1 || errno != ENOENT,
+	      "reuseport array lookup not-exist elem",
+	      "err:%d errno:%d\n", err, errno);
+	err = bpf_map_delete_elem(map_fd, &index3);
+	CHECK(err != -1 || errno != ENOENT,
+	      "reuseport array del not-exist elem",
+	      "err:%d errno:%d\n", err, errno);
+
+	for (t = 0; t < ARRAY_SIZE(types); t++) {
+		type = types[t];
+
+		prepare_reuseport_grp(type, map_fd, grpa_fds64,
+				      grpa_cookies, ARRAY_SIZE(grpa_fds64));
+
+		/* Test BPF_* update flags */
+		/* BPF_EXIST failure case */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_EXIST);
+		CHECK(err != -1 || errno != ENOENT,
+		      "reuseport array update empty elem BPF_EXIST",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_NOEXIST success case */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_NOEXIST);
+		CHECK(err == -1,
+		      "reuseport array update empty elem BPF_NOEXIST",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_EXIST success case. */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_EXIST);
+		CHECK(err == -1,
+		      "reuseport array update same elem BPF_EXIST",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_NOEXIST failure case */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_NOEXIST);
+		CHECK(err != -1 || errno != EEXIST,
+		      "reuseport array update non-empty elem BPF_NOEXIST",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_ANY case (always succeed) */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_ANY);
+		CHECK(err == -1,
+		      "reuseport array update same sk with BPF_ANY",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		fd64 = grpa_fds64[fds_idx];
+		sk_cookie = grpa_cookies[fds_idx];
+
+		/* The same sk cannot be added to reuseport_array twice */
+		err = bpf_map_update_elem(map_fd, &index3, &fd64, BPF_ANY);
+		CHECK(err != -1 || errno != EBUSY,
+		      "reuseport array update same sk with same index",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		err = bpf_map_update_elem(map_fd, &index0, &fd64, BPF_ANY);
+		CHECK(err != -1 || errno != EBUSY,
+		      "reuseport array update same sk with different index",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		/* Test delete elem */
+		err = bpf_map_delete_elem(map_fd, &index3);
+		CHECK(err == -1, "reuseport array delete sk",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		/* Add it back with BPF_NOEXIST */
+		err = bpf_map_update_elem(map_fd, &index3, &fd64, BPF_NOEXIST);
+		CHECK(err == -1,
+		      "reuseport array re-add with BPF_NOEXIST after del",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		/* Test cookie */
+		err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+		CHECK(err == -1 || sk_cookie != map_cookie,
+		      "reuseport array lookup re-added sk",
+		      "sock_type:%d err:%d errno:%d sk_cookie:0x%llx map_cookie:0x%llxn",
+		      type, err, errno, sk_cookie, map_cookie);
+
+		/* Test elem removed by close() */
+		for (f = 0; f < ARRAY_SIZE(grpa_fds64); f++)
+			close(grpa_fds64[f]);
+		err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+		CHECK(err != -1 || errno != ENOENT,
+		      "reuseport array lookup after close()",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+	}
+
+	/* Test SOCK_RAW */
+	fd64 = socket(AF_INET6, SOCK_RAW, IPPROTO_UDP);
+	CHECK(fd64 == -1, "socket(SOCK_RAW)", "err:%d errno:%d\n",
+	      err, errno);
+	err = bpf_map_update_elem(map_fd, &index3, &fd64, BPF_NOEXIST);
+	CHECK(err != -1 || errno != ENOTSUPP, "reuseport array update SOCK_RAW",
+	      "err:%d errno:%d\n", err, errno);
+	close(fd64);
+
+	/* Close the 64 bit value map */
+	close(map_fd);
+
+	/* Test 32 bit fd */
+	map_fd = bpf_create_map(BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
+				sizeof(__u32), sizeof(__u32), array_size, 0);
+	CHECK(map_fd == -1, "reuseport array create",
+	      "map_fd:%d, errno:%d\n", map_fd, errno);
+	prepare_reuseport_grp(SOCK_STREAM, map_fd, &fd64, &sk_cookie, 1);
+	fd = fd64;
+	err = bpf_map_update_elem(map_fd, &index3, &fd, BPF_NOEXIST);
+	CHECK(err == -1, "reuseport array update 32 bit fd",
+	      "err:%d errno:%d\n", err, errno);
+	err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+	CHECK(err != -1 || errno != ENOSPC,
+	      "reuseport array lookup 32 bit fd",
+	      "err:%d errno:%d\n", err, errno);
+	close(fd);
+	close(map_fd);
+}
+
 static void run_all_tests(void)
 {
 	test_hashmap(0, NULL);
@@ -1170,6 +1428,8 @@ static void run_all_tests(void)
 
 	test_map_rdonly();
 	test_map_wronly();
+
+	test_reuseport_array();
 }
 
 int main(void)