1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright (C) 2017 Facebook
3 // Author: Roman Gushchin <guro@fb.com>
5 #define _XOPEN_SOURCE 500
14 #include <sys/types.h>
21 #define HELP_SPEC_ATTACH_FLAGS \
22 "ATTACH_FLAGS := { multi | override }"
24 #define HELP_SPEC_ATTACH_TYPES \
25 " ATTACH_TYPE := { ingress | egress | sock_create |\n" \
26 " sock_ops | device | bind4 | bind6 |\n" \
27 " post_bind4 | post_bind6 | connect4 |\n" \
28 " connect6 | sendmsg4 | sendmsg6 }"
30 static const char * const attach_type_strings[] = {
31 [BPF_CGROUP_INET_INGRESS] = "ingress",
32 [BPF_CGROUP_INET_EGRESS] = "egress",
33 [BPF_CGROUP_INET_SOCK_CREATE] = "sock_create",
34 [BPF_CGROUP_SOCK_OPS] = "sock_ops",
35 [BPF_CGROUP_DEVICE] = "device",
36 [BPF_CGROUP_INET4_BIND] = "bind4",
37 [BPF_CGROUP_INET6_BIND] = "bind6",
38 [BPF_CGROUP_INET4_CONNECT] = "connect4",
39 [BPF_CGROUP_INET6_CONNECT] = "connect6",
40 [BPF_CGROUP_INET4_POST_BIND] = "post_bind4",
41 [BPF_CGROUP_INET6_POST_BIND] = "post_bind6",
42 [BPF_CGROUP_UDP4_SENDMSG] = "sendmsg4",
43 [BPF_CGROUP_UDP6_SENDMSG] = "sendmsg6",
44 [__MAX_BPF_ATTACH_TYPE] = NULL,
47 static enum bpf_attach_type parse_attach_type(const char *str)
49 enum bpf_attach_type type;
51 for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) {
52 if (attach_type_strings[type] &&
53 is_prefix(str, attach_type_strings[type]))
57 return __MAX_BPF_ATTACH_TYPE;
60 static int show_bpf_prog(int id, const char *attach_type_str,
61 const char *attach_flags_str,
64 struct bpf_prog_info info = {};
65 __u32 info_len = sizeof(info);
68 prog_fd = bpf_prog_get_fd_by_id(id);
72 if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len)) {
78 jsonw_start_object(json_wtr);
79 jsonw_uint_field(json_wtr, "id", info.id);
80 jsonw_string_field(json_wtr, "attach_type",
82 jsonw_string_field(json_wtr, "attach_flags",
84 jsonw_string_field(json_wtr, "name", info.name);
85 jsonw_end_object(json_wtr);
87 printf("%s%-8u %-15s %-15s %-15s\n", level ? " " : "",
98 static int count_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type)
103 ret = bpf_prog_query(cgroup_fd, type, 0, NULL, NULL, &prog_cnt);
110 static int show_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type,
113 __u32 prog_ids[1024] = {0};
114 char *attach_flags_str;
115 __u32 prog_cnt, iter;
120 prog_cnt = ARRAY_SIZE(prog_ids);
121 ret = bpf_prog_query(cgroup_fd, type, 0, &attach_flags, prog_ids,
129 switch (attach_flags) {
130 case BPF_F_ALLOW_MULTI:
131 attach_flags_str = "multi";
133 case BPF_F_ALLOW_OVERRIDE:
134 attach_flags_str = "override";
137 attach_flags_str = "";
140 snprintf(buf, sizeof(buf), "unknown(%x)", attach_flags);
141 attach_flags_str = buf;
144 for (iter = 0; iter < prog_cnt; iter++)
145 show_bpf_prog(prog_ids[iter], attach_type_strings[type],
146 attach_flags_str, level);
151 static int do_show(int argc, char **argv)
153 enum bpf_attach_type type;
158 p_err("too few parameters for cgroup show");
160 } else if (argc > 1) {
161 p_err("too many parameters for cgroup show");
165 cgroup_fd = open(argv[0], O_RDONLY);
167 p_err("can't open cgroup %s", argv[0]);
172 jsonw_start_array(json_wtr);
174 printf("%-8s %-15s %-15s %-15s\n", "ID", "AttachType",
175 "AttachFlags", "Name");
177 for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) {
179 * Not all attach types may be supported, so it's expected,
180 * that some requests will fail.
181 * If we were able to get the show for at least one
182 * attach type, let's return 0.
184 if (show_attached_bpf_progs(cgroup_fd, type, 0) == 0)
189 jsonw_end_array(json_wtr);
197 * To distinguish nftw() errors and do_show_tree_fn() errors
198 * and avoid duplicating error messages, let's return -2
199 * from do_show_tree_fn() in case of error.
202 #define SHOW_TREE_FN_ERR -2
203 static int do_show_tree_fn(const char *fpath, const struct stat *sb,
204 int typeflag, struct FTW *ftw)
206 enum bpf_attach_type type;
210 if (typeflag != FTW_D)
213 cgroup_fd = open(fpath, O_RDONLY);
215 p_err("can't open cgroup %s: %s", fpath, strerror(errno));
216 return SHOW_TREE_FN_ERR;
219 for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) {
220 int count = count_attached_bpf_progs(cgroup_fd, type);
222 if (count < 0 && errno != EINVAL) {
223 p_err("can't query bpf programs attached to %s: %s",
224 fpath, strerror(errno));
226 return SHOW_TREE_FN_ERR;
240 jsonw_start_object(json_wtr);
241 jsonw_string_field(json_wtr, "cgroup", fpath);
242 jsonw_name(json_wtr, "programs");
243 jsonw_start_array(json_wtr);
245 printf("%s\n", fpath);
248 for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++)
249 show_attached_bpf_progs(cgroup_fd, type, ftw->level);
252 jsonw_end_array(json_wtr);
253 jsonw_end_object(json_wtr);
261 static char *find_cgroup_root(void)
266 f = fopen("/proc/mounts", "r");
270 while ((mnt = getmntent(f))) {
271 if (strcmp(mnt->mnt_type, "cgroup2") == 0) {
273 return strdup(mnt->mnt_dir);
281 static int do_show_tree(int argc, char **argv)
288 cgroup_root = find_cgroup_root();
290 p_err("cgroup v2 isn't mounted");
295 cgroup_root = argv[0];
298 p_err("too many parameters for cgroup tree");
304 jsonw_start_array(json_wtr);
307 "%-8s %-15s %-15s %-15s\n",
309 "ID", "AttachType", "AttachFlags", "Name");
311 switch (nftw(cgroup_root, do_show_tree_fn, 1024, FTW_MOUNT)) {
313 p_err("can't iterate over %s: %s", cgroup_root,
317 case SHOW_TREE_FN_ERR:
325 jsonw_end_array(json_wtr);
333 static int do_attach(int argc, char **argv)
335 enum bpf_attach_type attach_type;
336 int cgroup_fd, prog_fd;
337 int attach_flags = 0;
342 p_err("too few parameters for cgroup attach");
346 cgroup_fd = open(argv[0], O_RDONLY);
348 p_err("can't open cgroup %s", argv[0]);
352 attach_type = parse_attach_type(argv[1]);
353 if (attach_type == __MAX_BPF_ATTACH_TYPE) {
354 p_err("invalid attach type");
360 prog_fd = prog_parse_fd(&argc, &argv);
364 for (i = 0; i < argc; i++) {
365 if (is_prefix(argv[i], "multi")) {
366 attach_flags |= BPF_F_ALLOW_MULTI;
367 } else if (is_prefix(argv[i], "override")) {
368 attach_flags |= BPF_F_ALLOW_OVERRIDE;
370 p_err("unknown option: %s", argv[i]);
375 if (bpf_prog_attach(prog_fd, cgroup_fd, attach_type, attach_flags)) {
376 p_err("failed to attach program");
381 jsonw_null(json_wtr);
393 static int do_detach(int argc, char **argv)
395 enum bpf_attach_type attach_type;
396 int prog_fd, cgroup_fd;
400 p_err("too few parameters for cgroup detach");
404 cgroup_fd = open(argv[0], O_RDONLY);
406 p_err("can't open cgroup %s", argv[0]);
410 attach_type = parse_attach_type(argv[1]);
411 if (attach_type == __MAX_BPF_ATTACH_TYPE) {
412 p_err("invalid attach type");
418 prog_fd = prog_parse_fd(&argc, &argv);
422 if (bpf_prog_detach2(prog_fd, cgroup_fd, attach_type)) {
423 p_err("failed to detach program");
428 jsonw_null(json_wtr);
440 static int do_help(int argc, char **argv)
443 jsonw_null(json_wtr);
448 "Usage: %s %s { show | list } CGROUP\n"
449 " %s %s tree [CGROUP_ROOT]\n"
450 " %s %s attach CGROUP ATTACH_TYPE PROG [ATTACH_FLAGS]\n"
451 " %s %s detach CGROUP ATTACH_TYPE PROG\n"
454 HELP_SPEC_ATTACH_TYPES "\n"
455 " " HELP_SPEC_ATTACH_FLAGS "\n"
456 " " HELP_SPEC_PROGRAM "\n"
457 " " HELP_SPEC_OPTIONS "\n"
460 bin_name, argv[-2], bin_name, argv[-2],
461 bin_name, argv[-2], bin_name, argv[-2]);
466 static const struct cmd cmds[] = {
469 { "tree", do_show_tree },
470 { "attach", do_attach },
471 { "detach", do_detach },
476 int do_cgroup(int argc, char **argv)
478 return cmd_select(cmds, argc, argv, do_help);