1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2017 Facebook
4  */
5 #include <sys/socket.h>
6 #include <arpa/inet.h>
7 #include <stdint.h>
8 #include <assert.h>
9 #include <errno.h>
10 #include <stdlib.h>
11 #include <stdio.h>
12 #include <bpf/bpf.h>
13 #include <bpf/libbpf.h>
14 
15 #include "bpf_util.h"
16 
17 static int map_fd[7];
18 
19 #define PORT_A		(map_fd[0])
20 #define PORT_H		(map_fd[1])
21 #define REG_RESULT_H	(map_fd[2])
22 #define INLINE_RESULT_H	(map_fd[3])
23 #define A_OF_PORT_A	(map_fd[4]) /* Test case #0 */
24 #define H_OF_PORT_A	(map_fd[5]) /* Test case #1 */
25 #define H_OF_PORT_H	(map_fd[6]) /* Test case #2 */
26 
27 static const char * const test_names[] = {
28 	"Array of Array",
29 	"Hash of Array",
30 	"Hash of Hash",
31 };
32 
33 #define NR_TESTS ARRAY_SIZE(test_names)
34 
35 static void check_map_id(int inner_map_fd, int map_in_map_fd, uint32_t key)
36 {
37 	struct bpf_map_info info = {};
38 	uint32_t info_len = sizeof(info);
39 	int ret, id;
40 
41 	ret = bpf_obj_get_info_by_fd(inner_map_fd, &info, &info_len);
42 	assert(!ret);
43 
44 	ret = bpf_map_lookup_elem(map_in_map_fd, &key, &id);
45 	assert(!ret);
46 	assert(id == info.id);
47 }
48 
49 static void populate_map(uint32_t port_key, int magic_result)
50 {
51 	int ret;
52 
53 	ret = bpf_map_update_elem(PORT_A, &port_key, &magic_result, BPF_ANY);
54 	assert(!ret);
55 
56 	ret = bpf_map_update_elem(PORT_H, &port_key, &magic_result,
57 				  BPF_NOEXIST);
58 	assert(!ret);
59 
60 	ret = bpf_map_update_elem(A_OF_PORT_A, &port_key, &PORT_A, BPF_ANY);
61 	assert(!ret);
62 	check_map_id(PORT_A, A_OF_PORT_A, port_key);
63 
64 	ret = bpf_map_update_elem(H_OF_PORT_A, &port_key, &PORT_A, BPF_NOEXIST);
65 	assert(!ret);
66 	check_map_id(PORT_A, H_OF_PORT_A, port_key);
67 
68 	ret = bpf_map_update_elem(H_OF_PORT_H, &port_key, &PORT_H, BPF_NOEXIST);
69 	assert(!ret);
70 	check_map_id(PORT_H, H_OF_PORT_H, port_key);
71 }
72 
73 static void test_map_in_map(void)
74 {
75 	struct sockaddr_in6 in6 = { .sin6_family = AF_INET6 };
76 	uint32_t result_key = 0, port_key;
77 	int result, inline_result;
78 	int magic_result = 0xfaceb00c;
79 	int ret;
80 	int i;
81 
82 	port_key = rand() & 0x00FF;
83 	populate_map(port_key, magic_result);
84 
85 	in6.sin6_addr.s6_addr16[0] = 0xdead;
86 	in6.sin6_addr.s6_addr16[1] = 0xbeef;
87 	in6.sin6_port = port_key;
88 
89 	for (i = 0; i < NR_TESTS; i++) {
90 		printf("%s: ", test_names[i]);
91 
92 		in6.sin6_addr.s6_addr16[7] = i;
93 		ret = connect(-1, (struct sockaddr *)&in6, sizeof(in6));
94 		assert(ret == -1 && errno == EBADF);
95 
96 		ret = bpf_map_lookup_elem(REG_RESULT_H, &result_key, &result);
97 		assert(!ret);
98 
99 		ret = bpf_map_lookup_elem(INLINE_RESULT_H, &result_key,
100 					  &inline_result);
101 		assert(!ret);
102 
103 		if (result != magic_result || inline_result != magic_result) {
104 			printf("Error. result:%d inline_result:%d\n",
105 			       result, inline_result);
106 			exit(1);
107 		}
108 
109 		bpf_map_delete_elem(REG_RESULT_H, &result_key);
110 		bpf_map_delete_elem(INLINE_RESULT_H, &result_key);
111 
112 		printf("Pass\n");
113 	}
114 }
115 
116 int main(int argc, char **argv)
117 {
118 	struct bpf_link *link = NULL;
119 	struct bpf_program *prog;
120 	struct bpf_object *obj;
121 	char filename[256];
122 
123 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
124 	obj = bpf_object__open_file(filename, NULL);
125 	if (libbpf_get_error(obj)) {
126 		fprintf(stderr, "ERROR: opening BPF object file failed\n");
127 		return 0;
128 	}
129 
130 	prog = bpf_object__find_program_by_name(obj, "trace_sys_connect");
131 	if (!prog) {
132 		printf("finding a prog in obj file failed\n");
133 		goto cleanup;
134 	}
135 
136 	/* load BPF program */
137 	if (bpf_object__load(obj)) {
138 		fprintf(stderr, "ERROR: loading BPF object file failed\n");
139 		goto cleanup;
140 	}
141 
142 	map_fd[0] = bpf_object__find_map_fd_by_name(obj, "port_a");
143 	map_fd[1] = bpf_object__find_map_fd_by_name(obj, "port_h");
144 	map_fd[2] = bpf_object__find_map_fd_by_name(obj, "reg_result_h");
145 	map_fd[3] = bpf_object__find_map_fd_by_name(obj, "inline_result_h");
146 	map_fd[4] = bpf_object__find_map_fd_by_name(obj, "a_of_port_a");
147 	map_fd[5] = bpf_object__find_map_fd_by_name(obj, "h_of_port_a");
148 	map_fd[6] = bpf_object__find_map_fd_by_name(obj, "h_of_port_h");
149 	if (map_fd[0] < 0 || map_fd[1] < 0 || map_fd[2] < 0 ||
150 	    map_fd[3] < 0 || map_fd[4] < 0 || map_fd[5] < 0 || map_fd[6] < 0) {
151 		fprintf(stderr, "ERROR: finding a map in obj file failed\n");
152 		goto cleanup;
153 	}
154 
155 	link = bpf_program__attach(prog);
156 	if (libbpf_get_error(link)) {
157 		fprintf(stderr, "ERROR: bpf_program__attach failed\n");
158 		link = NULL;
159 		goto cleanup;
160 	}
161 
162 	test_map_in_map();
163 
164 cleanup:
165 	bpf_link__destroy(link);
166 	bpf_object__close(obj);
167 	return 0;
168 }
169