Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2018 Facebook
3
4#include <string.h>
5#include <unistd.h>
6
7#include <arpa/inet.h>
8#include <netinet/in.h>
9#include <sys/types.h>
10#include <sys/socket.h>
11
12#include <bpf/bpf.h>
13#include <bpf/libbpf.h>
14
15#include "bpf_rlimit.h"
16#include "cgroup_helpers.h"
17
18#define CG_PATH "/foo"
19#define SOCKET_COOKIE_PROG "./socket_cookie_prog.o"
20
21static int start_server(void)
22{
23 struct sockaddr_in6 addr;
24 int fd;
25
26 fd = socket(AF_INET6, SOCK_STREAM, 0);
27 if (fd == -1) {
28 log_err("Failed to create server socket");
29 goto out;
30 }
31
32 memset(&addr, 0, sizeof(addr));
33 addr.sin6_family = AF_INET6;
34 addr.sin6_addr = in6addr_loopback;
35 addr.sin6_port = 0;
36
37 if (bind(fd, (const struct sockaddr *)&addr, sizeof(addr)) == -1) {
38 log_err("Failed to bind server socket");
39 goto close_out;
40 }
41
42 if (listen(fd, 128) == -1) {
43 log_err("Failed to listen on server socket");
44 goto close_out;
45 }
46
47 goto out;
48
49close_out:
50 close(fd);
51 fd = -1;
52out:
53 return fd;
54}
55
56static int connect_to_server(int server_fd)
57{
58 struct sockaddr_storage addr;
59 socklen_t len = sizeof(addr);
60 int fd;
61
62 fd = socket(AF_INET6, SOCK_STREAM, 0);
63 if (fd == -1) {
64 log_err("Failed to create client socket");
65 goto out;
66 }
67
68 if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
69 log_err("Failed to get server addr");
70 goto close_out;
71 }
72
73 if (connect(fd, (const struct sockaddr *)&addr, len) == -1) {
74 log_err("Fail to connect to server");
75 goto close_out;
76 }
77
78 goto out;
79
80close_out:
81 close(fd);
82 fd = -1;
83out:
84 return fd;
85}
86
87static int validate_map(struct bpf_map *map, int client_fd)
88{
89 __u32 cookie_expected_value;
90 struct sockaddr_in6 addr;
91 socklen_t len = sizeof(addr);
92 __u32 cookie_value;
93 __u64 cookie_key;
94 int err = 0;
95 int map_fd;
96
97 if (!map) {
98 log_err("Map not found in BPF object");
99 goto err;
100 }
101
102 map_fd = bpf_map__fd(map);
103
104 err = bpf_map_get_next_key(map_fd, NULL, &cookie_key);
105 if (err) {
106 log_err("Can't get cookie key from map");
107 goto out;
108 }
109
110 err = bpf_map_lookup_elem(map_fd, &cookie_key, &cookie_value);
111 if (err) {
112 log_err("Can't get cookie value from map");
113 goto out;
114 }
115
116 err = getsockname(client_fd, (struct sockaddr *)&addr, &len);
117 if (err) {
118 log_err("Can't get client local addr");
119 goto out;
120 }
121
122 cookie_expected_value = (ntohs(addr.sin6_port) << 8) | 0xFF;
123 if (cookie_value != cookie_expected_value) {
124 log_err("Unexpected value in map: %x != %x", cookie_value,
125 cookie_expected_value);
126 goto err;
127 }
128
129 goto out;
130err:
131 err = -1;
132out:
133 return err;
134}
135
136static int run_test(int cgfd)
137{
138 enum bpf_attach_type attach_type;
139 struct bpf_prog_load_attr attr;
140 struct bpf_program *prog;
141 struct bpf_object *pobj;
142 const char *prog_name;
143 int server_fd = -1;
144 int client_fd = -1;
145 int prog_fd = -1;
146 int err = 0;
147
148 memset(&attr, 0, sizeof(attr));
149 attr.file = SOCKET_COOKIE_PROG;
150 attr.prog_type = BPF_PROG_TYPE_UNSPEC;
151
152 err = bpf_prog_load_xattr(&attr, &pobj, &prog_fd);
153 if (err) {
154 log_err("Failed to load %s", attr.file);
155 goto out;
156 }
157
158 bpf_object__for_each_program(prog, pobj) {
159 prog_name = bpf_program__title(prog, /*needs_copy*/ false);
160
161 if (libbpf_attach_type_by_name(prog_name, &attach_type)) {
162 log_err("Unexpected prog: %s", prog_name);
163 goto err;
164 }
165
166 err = bpf_prog_attach(bpf_program__fd(prog), cgfd, attach_type,
167 BPF_F_ALLOW_OVERRIDE);
168 if (err) {
169 log_err("Failed to attach prog %s", prog_name);
170 goto out;
171 }
172 }
173
174 server_fd = start_server();
175 if (server_fd == -1)
176 goto err;
177
178 client_fd = connect_to_server(server_fd);
179 if (client_fd == -1)
180 goto err;
181
182 if (validate_map(bpf_map__next(NULL, pobj), client_fd))
183 goto err;
184
185 goto out;
186err:
187 err = -1;
188out:
189 close(client_fd);
190 close(server_fd);
191 bpf_object__close(pobj);
192 printf("%s\n", err ? "FAILED" : "PASSED");
193 return err;
194}
195
196int main(int argc, char **argv)
197{
198 int cgfd = -1;
199 int err = 0;
200
201 if (setup_cgroup_environment())
202 goto err;
203
204 cgfd = create_and_get_cgroup(CG_PATH);
205 if (cgfd < 0)
206 goto err;
207
208 if (join_cgroup(CG_PATH))
209 goto err;
210
211 if (run_test(cgfd))
212 goto err;
213
214 goto out;
215err:
216 err = -1;
217out:
218 close(cgfd);
219 cleanup_cgroup_environment();
220 return err;
221}