1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2018 Facebook
10 #include <netinet/in.h>
11 #include <sys/socket.h>
12 #include <sys/types.h>
16 #include <bpf/libbpf.h>
18 #include "bpf_rlimit.h"
19 #include "cgroup_helpers.h"
21 #define CGROUP_PATH "/skb_cgroup_test"
22 #define NUM_CGROUP_LEVELS 4
24 /* RFC 4291, Section 2.7.1 */
25 #define LINKLOCAL_MULTICAST "ff02::1"
27 static int mk_dst_addr(const char *ip, const char *iface,
28 struct sockaddr_in6 *dst)
30 memset(dst, 0, sizeof(*dst));
32 dst->sin6_family = AF_INET6;
33 dst->sin6_port = htons(1025);
35 if (inet_pton(AF_INET6, ip, &dst->sin6_addr) != 1) {
36 log_err("Invalid IPv6: %s", ip);
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);
49 static int send_packet(const char *iface)
51 struct sockaddr_in6 dst;
56 if (mk_dst_addr(LINKLOCAL_MULTICAST, iface, &dst))
59 fd = socket(AF_INET6, SOCK_DGRAM, 0);
61 log_err("Failed to create UDP socket");
65 if (sendto(fd, &msg, sizeof(msg), 0, (const struct sockaddr *)&dst,
67 log_err("Failed to send datagram");
80 int get_map_fd_by_prog_id(int prog_id)
82 struct bpf_prog_info info = {};
83 __u32 info_len = sizeof(info);
88 prog_fd = bpf_prog_get_fd_by_id(prog_id);
90 log_err("Failed to get fd by prog id %d", prog_id);
95 info.map_ids = (__u64) (unsigned long) map_ids;
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);
102 if (!info.nr_map_ids) {
103 log_err("No maps found for prog fd %d", prog_fd);
107 map_fd = bpf_map_get_fd_by_id(map_ids[0]);
109 log_err("Failed to get fd by map id %d", map_ids[0]);
116 int check_ancestor_cgroup_ids(int prog_id)
118 __u64 actual_ids[NUM_CGROUP_LEVELS], expected_ids[NUM_CGROUP_LEVELS];
123 expected_ids[0] = get_cgroup_id("/.."); /* 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 */
128 map_fd = get_map_fd_by_prog_id(prog_id);
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);
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);
153 int main(int argc, char **argv)
159 fprintf(stderr, "Usage: %s iface prog_id\n", argv[0]);
163 cgfd = cgroup_setup_and_join(CGROUP_PATH);
167 if (send_packet(argv[1]))
170 if (check_ancestor_cgroup_ids(atoi(argv[2])))
178 cleanup_cgroup_environment();
179 printf("[%s]\n", err ? "FAIL" : "PASS");