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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 "cgroup_helpers.h"
19
20#define CGROUP_PATH "/skb_cgroup_test"
21#define NUM_CGROUP_LEVELS 4
22
23/* RFC 4291, Section 2.7.1 */
24#define LINKLOCAL_MULTICAST "ff02::1"
25
26static int mk_dst_addr(const char *ip, const char *iface,
27 struct sockaddr_in6 *dst)
28{
29 memset(dst, 0, sizeof(*dst));
30
31 dst->sin6_family = AF_INET6;
32 dst->sin6_port = htons(1025);
33
34 if (inet_pton(AF_INET6, ip, &dst->sin6_addr) != 1) {
35 log_err("Invalid IPv6: %s", ip);
36 return -1;
37 }
38
39 dst->sin6_scope_id = if_nametoindex(iface);
40 if (!dst->sin6_scope_id) {
41 log_err("Failed to get index of iface: %s", iface);
42 return -1;
43 }
44
45 return 0;
46}
47
48static int send_packet(const char *iface)
49{
50 struct sockaddr_in6 dst;
51 char msg[] = "msg";
52 int err = 0;
53 int fd = -1;
54
55 if (mk_dst_addr(LINKLOCAL_MULTICAST, iface, &dst))
56 goto err;
57
58 fd = socket(AF_INET6, SOCK_DGRAM, 0);
59 if (fd == -1) {
60 log_err("Failed to create UDP socket");
61 goto err;
62 }
63
64 if (sendto(fd, &msg, sizeof(msg), 0, (const struct sockaddr *)&dst,
65 sizeof(dst)) == -1) {
66 log_err("Failed to send datagram");
67 goto err;
68 }
69
70 goto out;
71err:
72 err = -1;
73out:
74 if (fd >= 0)
75 close(fd);
76 return err;
77}
78
79int get_map_fd_by_prog_id(int prog_id)
80{
81 struct bpf_prog_info info = {};
82 __u32 info_len = sizeof(info);
83 __u32 map_ids[1];
84 int prog_fd = -1;
85 int map_fd = -1;
86
87 prog_fd = bpf_prog_get_fd_by_id(prog_id);
88 if (prog_fd < 0) {
89 log_err("Failed to get fd by prog id %d", prog_id);
90 goto err;
91 }
92
93 info.nr_map_ids = 1;
94 info.map_ids = (__u64) (unsigned long) map_ids;
95
96 if (bpf_prog_get_info_by_fd(prog_fd, &info, &info_len)) {
97 log_err("Failed to get info by prog fd %d", prog_fd);
98 goto err;
99 }
100
101 if (!info.nr_map_ids) {
102 log_err("No maps found for prog fd %d", prog_fd);
103 goto err;
104 }
105
106 map_fd = bpf_map_get_fd_by_id(map_ids[0]);
107 if (map_fd < 0)
108 log_err("Failed to get fd by map id %d", map_ids[0]);
109err:
110 if (prog_fd >= 0)
111 close(prog_fd);
112 return map_fd;
113}
114
115int check_ancestor_cgroup_ids(int prog_id)
116{
117 __u64 actual_ids[NUM_CGROUP_LEVELS], expected_ids[NUM_CGROUP_LEVELS];
118 __u32 level;
119 int err = 0;
120 int map_fd;
121
122 expected_ids[0] = get_cgroup_id("/.."); /* root cgroup */
123 expected_ids[1] = get_cgroup_id("");
124 expected_ids[2] = get_cgroup_id(CGROUP_PATH);
125 expected_ids[3] = 0; /* non-existent cgroup */
126
127 map_fd = get_map_fd_by_prog_id(prog_id);
128 if (map_fd < 0)
129 goto err;
130
131 for (level = 0; level < NUM_CGROUP_LEVELS; ++level) {
132 if (bpf_map_lookup_elem(map_fd, &level, &actual_ids[level])) {
133 log_err("Failed to lookup key %d", level);
134 goto err;
135 }
136 if (actual_ids[level] != expected_ids[level]) {
137 log_err("%llx (actual) != %llx (expected), level: %u\n",
138 actual_ids[level], expected_ids[level], level);
139 goto err;
140 }
141 }
142
143 goto out;
144err:
145 err = -1;
146out:
147 if (map_fd >= 0)
148 close(map_fd);
149 return err;
150}
151
152int main(int argc, char **argv)
153{
154 int cgfd = -1;
155 int err = 0;
156
157 if (argc < 3) {
158 fprintf(stderr, "Usage: %s iface prog_id\n", argv[0]);
159 exit(EXIT_FAILURE);
160 }
161
162 /* Use libbpf 1.0 API mode */
163 libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
164
165 cgfd = cgroup_setup_and_join(CGROUP_PATH);
166 if (cgfd < 0)
167 goto err;
168
169 if (send_packet(argv[1]))
170 goto err;
171
172 if (check_ancestor_cgroup_ids(atoi(argv[2])))
173 goto err;
174
175 goto out;
176err:
177 err = -1;
178out:
179 close(cgfd);
180 cleanup_cgroup_environment();
181 printf("[%s]\n", err ? "FAIL" : "PASS");
182 return err;
183}
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
27static 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
49static 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;
72err:
73 err = -1;
74out:
75 if (fd >= 0)
76 close(fd);
77 return err;
78}
79
80int 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]);
110err:
111 if (prog_fd >= 0)
112 close(prog_fd);
113 return map_fd;
114}
115
116int 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;
145err:
146 err = -1;
147out:
148 if (map_fd >= 0)
149 close(map_fd);
150 return err;
151}
152
153int 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);
167 if (cgfd < 0)
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;
180err:
181 err = -1;
182out:
183 close(cgfd);
184 cleanup_cgroup_environment();
185 printf("[%s]\n", err ? "FAIL" : "PASS");
186 return err;
187}