]>
Commit | Line | Data |
---|---|---|
5ecd8c22 AI |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // Copyright (c) 2018 Facebook | |
3 | ||
4 | #include <stdlib.h> | |
5 | #include <string.h> | |
6 | #include <unistd.h> | |
7 | ||
8 | #include <arpa/inet.h> | |
9 | #include <net/if.h> | |
10 | #include <netinet/in.h> | |
11 | #include <sys/socket.h> | |
12 | #include <sys/types.h> | |
13 | ||
14 | ||
15 | #include <bpf/bpf.h> | |
16 | #include <bpf/libbpf.h> | |
17 | ||
18 | #include "bpf_rlimit.h" | |
19 | #include "cgroup_helpers.h" | |
20 | ||
21 | #define CGROUP_PATH "/skb_cgroup_test" | |
22 | #define NUM_CGROUP_LEVELS 4 | |
23 | ||
24 | /* RFC 4291, Section 2.7.1 */ | |
25 | #define LINKLOCAL_MULTICAST "ff02::1" | |
26 | ||
27 | static int mk_dst_addr(const char *ip, const char *iface, | |
28 | struct sockaddr_in6 *dst) | |
29 | { | |
30 | memset(dst, 0, sizeof(*dst)); | |
31 | ||
32 | dst->sin6_family = AF_INET6; | |
33 | dst->sin6_port = htons(1025); | |
34 | ||
35 | if (inet_pton(AF_INET6, ip, &dst->sin6_addr) != 1) { | |
36 | log_err("Invalid IPv6: %s", ip); | |
37 | return -1; | |
38 | } | |
39 | ||
40 | dst->sin6_scope_id = if_nametoindex(iface); | |
41 | if (!dst->sin6_scope_id) { | |
42 | log_err("Failed to get index of iface: %s", iface); | |
43 | return -1; | |
44 | } | |
45 | ||
46 | return 0; | |
47 | } | |
48 | ||
49 | static int send_packet(const char *iface) | |
50 | { | |
51 | struct sockaddr_in6 dst; | |
52 | char msg[] = "msg"; | |
53 | int err = 0; | |
54 | int fd = -1; | |
55 | ||
56 | if (mk_dst_addr(LINKLOCAL_MULTICAST, iface, &dst)) | |
57 | goto err; | |
58 | ||
59 | fd = socket(AF_INET6, SOCK_DGRAM, 0); | |
60 | if (fd == -1) { | |
61 | log_err("Failed to create UDP socket"); | |
62 | goto err; | |
63 | } | |
64 | ||
65 | if (sendto(fd, &msg, sizeof(msg), 0, (const struct sockaddr *)&dst, | |
66 | sizeof(dst)) == -1) { | |
67 | log_err("Failed to send datagram"); | |
68 | goto err; | |
69 | } | |
70 | ||
71 | goto out; | |
72 | err: | |
73 | err = -1; | |
74 | out: | |
75 | if (fd >= 0) | |
76 | close(fd); | |
77 | return err; | |
78 | } | |
79 | ||
80 | int get_map_fd_by_prog_id(int prog_id) | |
81 | { | |
82 | struct bpf_prog_info info = {}; | |
83 | __u32 info_len = sizeof(info); | |
84 | __u32 map_ids[1]; | |
85 | int prog_fd = -1; | |
86 | int map_fd = -1; | |
87 | ||
88 | prog_fd = bpf_prog_get_fd_by_id(prog_id); | |
89 | if (prog_fd < 0) { | |
90 | log_err("Failed to get fd by prog id %d", prog_id); | |
91 | goto err; | |
92 | } | |
93 | ||
94 | info.nr_map_ids = 1; | |
95 | info.map_ids = (__u64) (unsigned long) map_ids; | |
96 | ||
97 | if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len)) { | |
98 | log_err("Failed to get info by prog fd %d", prog_fd); | |
99 | goto err; | |
100 | } | |
101 | ||
102 | if (!info.nr_map_ids) { | |
103 | log_err("No maps found for prog fd %d", prog_fd); | |
104 | goto err; | |
105 | } | |
106 | ||
107 | map_fd = bpf_map_get_fd_by_id(map_ids[0]); | |
108 | if (map_fd < 0) | |
109 | log_err("Failed to get fd by map id %d", map_ids[0]); | |
110 | err: | |
111 | if (prog_fd >= 0) | |
112 | close(prog_fd); | |
113 | return map_fd; | |
114 | } | |
115 | ||
116 | int check_ancestor_cgroup_ids(int prog_id) | |
117 | { | |
118 | __u64 actual_ids[NUM_CGROUP_LEVELS], expected_ids[NUM_CGROUP_LEVELS]; | |
119 | __u32 level; | |
120 | int err = 0; | |
121 | int map_fd; | |
122 | ||
123 | expected_ids[0] = 0x100000001; /* root cgroup */ | |
124 | expected_ids[1] = get_cgroup_id(""); | |
125 | expected_ids[2] = get_cgroup_id(CGROUP_PATH); | |
126 | expected_ids[3] = 0; /* non-existent cgroup */ | |
127 | ||
128 | map_fd = get_map_fd_by_prog_id(prog_id); | |
129 | if (map_fd < 0) | |
130 | goto err; | |
131 | ||
132 | for (level = 0; level < NUM_CGROUP_LEVELS; ++level) { | |
133 | if (bpf_map_lookup_elem(map_fd, &level, &actual_ids[level])) { | |
134 | log_err("Failed to lookup key %d", level); | |
135 | goto err; | |
136 | } | |
137 | if (actual_ids[level] != expected_ids[level]) { | |
138 | log_err("%llx (actual) != %llx (expected), level: %u\n", | |
139 | actual_ids[level], expected_ids[level], level); | |
140 | goto err; | |
141 | } | |
142 | } | |
143 | ||
144 | goto out; | |
145 | err: | |
146 | err = -1; | |
147 | out: | |
148 | if (map_fd >= 0) | |
149 | close(map_fd); | |
150 | return err; | |
151 | } | |
152 | ||
153 | int main(int argc, char **argv) | |
154 | { | |
155 | int cgfd = -1; | |
156 | int err = 0; | |
157 | ||
158 | if (argc < 3) { | |
159 | fprintf(stderr, "Usage: %s iface prog_id\n", argv[0]); | |
160 | exit(EXIT_FAILURE); | |
161 | } | |
162 | ||
163 | if (setup_cgroup_environment()) | |
164 | goto err; | |
165 | ||
166 | cgfd = create_and_get_cgroup(CGROUP_PATH); | |
a8911d6d | 167 | if (cgfd < 0) |
5ecd8c22 AI |
168 | goto err; |
169 | ||
170 | if (join_cgroup(CGROUP_PATH)) | |
171 | goto err; | |
172 | ||
173 | if (send_packet(argv[1])) | |
174 | goto err; | |
175 | ||
176 | if (check_ancestor_cgroup_ids(atoi(argv[2]))) | |
177 | goto err; | |
178 | ||
179 | goto out; | |
180 | err: | |
181 | err = -1; | |
182 | out: | |
183 | close(cgfd); | |
184 | cleanup_cgroup_environment(); | |
185 | printf("[%s]\n", err ? "FAIL" : "PASS"); | |
186 | return err; | |
187 | } |