xref: /linux/tools/bpf/bpftool/common.c (revision fa593d0f969dcfa41d390822fdf1a0ab48cd882c)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2017-2018 Netronome Systems, Inc. */
3 
4 #ifndef _GNU_SOURCE
5 #define _GNU_SOURCE
6 #endif
7 #include <ctype.h>
8 #include <errno.h>
9 #include <fcntl.h>
10 #include <ftw.h>
11 #include <libgen.h>
12 #include <mntent.h>
13 #include <stdbool.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include <unistd.h>
18 #include <net/if.h>
19 #include <sys/mount.h>
20 #include <sys/resource.h>
21 #include <sys/stat.h>
22 #include <sys/vfs.h>
23 
24 #include <linux/filter.h>
25 #include <linux/limits.h>
26 #include <linux/magic.h>
27 #include <linux/unistd.h>
28 
29 #include <bpf/bpf.h>
30 #include <bpf/hashmap.h>
31 #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
32 #include <bpf/btf.h>
33 
34 #include "main.h"
35 
36 #ifndef BPF_FS_MAGIC
37 #define BPF_FS_MAGIC		0xcafe4a11
38 #endif
39 
40 void p_err(const char *fmt, ...)
41 {
42 	va_list ap;
43 
44 	va_start(ap, fmt);
45 	if (json_output) {
46 		jsonw_start_object(json_wtr);
47 		jsonw_name(json_wtr, "error");
48 		jsonw_vprintf_enquote(json_wtr, fmt, ap);
49 		jsonw_end_object(json_wtr);
50 	} else {
51 		fprintf(stderr, "Error: ");
52 		vfprintf(stderr, fmt, ap);
53 		fprintf(stderr, "\n");
54 	}
55 	va_end(ap);
56 }
57 
58 void p_info(const char *fmt, ...)
59 {
60 	va_list ap;
61 
62 	if (json_output)
63 		return;
64 
65 	va_start(ap, fmt);
66 	vfprintf(stderr, fmt, ap);
67 	fprintf(stderr, "\n");
68 	va_end(ap);
69 }
70 
71 static bool is_bpffs(const char *path)
72 {
73 	struct statfs st_fs;
74 
75 	if (statfs(path, &st_fs) < 0)
76 		return false;
77 
78 	return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
79 }
80 
81 /* Probe whether kernel switched from memlock-based (RLIMIT_MEMLOCK) to
82  * memcg-based memory accounting for BPF maps and programs. This was done in
83  * commit 97306be45fbe ("Merge branch 'switch to memcg-based memory
84  * accounting'"), in Linux 5.11.
85  *
86  * Libbpf also offers to probe for memcg-based accounting vs rlimit, but does
87  * so by checking for the availability of a given BPF helper and this has
88  * failed on some kernels with backports in the past, see commit 6b4384ff1088
89  * ("Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"").
90  * Instead, we can probe by lowering the process-based rlimit to 0, trying to
91  * load a BPF object, and resetting the rlimit. If the load succeeds then
92  * memcg-based accounting is supported.
93  *
94  * This would be too dangerous to do in the library, because multithreaded
95  * applications might attempt to load items while the rlimit is at 0. Given
96  * that bpftool is single-threaded, this is fine to do here.
97  */
98 static bool known_to_need_rlimit(void)
99 {
100 	struct rlimit rlim_init, rlim_cur_zero = {};
101 	struct bpf_insn insns[] = {
102 		BPF_MOV64_IMM(BPF_REG_0, 0),
103 		BPF_EXIT_INSN(),
104 	};
105 	size_t insn_cnt = ARRAY_SIZE(insns);
106 	union bpf_attr attr;
107 	int prog_fd, err;
108 
109 	memset(&attr, 0, sizeof(attr));
110 	attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
111 	attr.insns = ptr_to_u64(insns);
112 	attr.insn_cnt = insn_cnt;
113 	attr.license = ptr_to_u64("GPL");
114 
115 	if (getrlimit(RLIMIT_MEMLOCK, &rlim_init))
116 		return false;
117 
118 	/* Drop the soft limit to zero. We maintain the hard limit to its
119 	 * current value, because lowering it would be a permanent operation
120 	 * for unprivileged users.
121 	 */
122 	rlim_cur_zero.rlim_max = rlim_init.rlim_max;
123 	if (setrlimit(RLIMIT_MEMLOCK, &rlim_cur_zero))
124 		return false;
125 
126 	/* Do not use bpf_prog_load() from libbpf here, because it calls
127 	 * bump_rlimit_memlock(), interfering with the current probe.
128 	 */
129 	prog_fd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
130 	err = errno;
131 
132 	/* reset soft rlimit to its initial value */
133 	setrlimit(RLIMIT_MEMLOCK, &rlim_init);
134 
135 	if (prog_fd < 0)
136 		return err == EPERM;
137 
138 	close(prog_fd);
139 	return false;
140 }
141 
142 void set_max_rlimit(void)
143 {
144 	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
145 
146 	if (known_to_need_rlimit())
147 		setrlimit(RLIMIT_MEMLOCK, &rinf);
148 }
149 
150 static int
151 mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
152 {
153 	bool bind_done = false;
154 
155 	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
156 		if (errno != EINVAL || bind_done) {
157 			snprintf(buff, bufflen,
158 				 "mount --make-private %s failed: %s",
159 				 target, strerror(errno));
160 			return -1;
161 		}
162 
163 		if (mount(target, target, "none", MS_BIND, NULL)) {
164 			snprintf(buff, bufflen,
165 				 "mount --bind %s %s failed: %s",
166 				 target, target, strerror(errno));
167 			return -1;
168 		}
169 
170 		bind_done = true;
171 	}
172 
173 	if (mount(type, target, type, 0, "mode=0700")) {
174 		snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
175 			 type, type, target, strerror(errno));
176 		return -1;
177 	}
178 
179 	return 0;
180 }
181 
182 int mount_tracefs(const char *target)
183 {
184 	char err_str[ERR_MAX_LEN];
185 	int err;
186 
187 	err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
188 	if (err) {
189 		err_str[ERR_MAX_LEN - 1] = '\0';
190 		p_err("can't mount tracefs: %s", err_str);
191 	}
192 
193 	return err;
194 }
195 
196 int open_obj_pinned(const char *path, bool quiet)
197 {
198 	char *pname;
199 	int fd = -1;
200 
201 	pname = strdup(path);
202 	if (!pname) {
203 		if (!quiet)
204 			p_err("mem alloc failed");
205 		goto out_ret;
206 	}
207 
208 	fd = bpf_obj_get(pname);
209 	if (fd < 0) {
210 		if (!quiet)
211 			p_err("bpf obj get (%s): %s", pname,
212 			      errno == EACCES && !is_bpffs(dirname(pname)) ?
213 			    "directory not in bpf file system (bpffs)" :
214 			    strerror(errno));
215 		goto out_free;
216 	}
217 
218 out_free:
219 	free(pname);
220 out_ret:
221 	return fd;
222 }
223 
224 int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)
225 {
226 	enum bpf_obj_type type;
227 	int fd;
228 
229 	fd = open_obj_pinned(path, false);
230 	if (fd < 0)
231 		return -1;
232 
233 	type = get_fd_type(fd);
234 	if (type < 0) {
235 		close(fd);
236 		return type;
237 	}
238 	if (type != exp_type) {
239 		p_err("incorrect object type: %s", get_fd_type_name(type));
240 		close(fd);
241 		return -1;
242 	}
243 
244 	return fd;
245 }
246 
247 int create_and_mount_bpffs_dir(const char *dir_name)
248 {
249 	char err_str[ERR_MAX_LEN];
250 	bool dir_exists;
251 	int err = 0;
252 
253 	if (is_bpffs(dir_name))
254 		return err;
255 
256 	dir_exists = access(dir_name, F_OK) == 0;
257 
258 	if (!dir_exists) {
259 		char *temp_name;
260 		char *parent_name;
261 
262 		temp_name = strdup(dir_name);
263 		if (!temp_name) {
264 			p_err("mem alloc failed");
265 			return -1;
266 		}
267 
268 		parent_name = dirname(temp_name);
269 
270 		if (is_bpffs(parent_name)) {
271 			/* nothing to do if already mounted */
272 			free(temp_name);
273 			return err;
274 		}
275 
276 		if (access(parent_name, F_OK) == -1) {
277 			p_err("can't create dir '%s' to pin BPF object: parent dir '%s' doesn't exist",
278 			      dir_name, parent_name);
279 			free(temp_name);
280 			return -1;
281 		}
282 
283 		free(temp_name);
284 	}
285 
286 	if (block_mount) {
287 		p_err("no BPF file system found, not mounting it due to --nomount option");
288 		return -1;
289 	}
290 
291 	if (!dir_exists) {
292 		err = mkdir(dir_name, S_IRWXU);
293 		if (err) {
294 			p_err("failed to create dir '%s': %s", dir_name, strerror(errno));
295 			return err;
296 		}
297 	}
298 
299 	err = mnt_fs(dir_name, "bpf", err_str, ERR_MAX_LEN);
300 	if (err) {
301 		err_str[ERR_MAX_LEN - 1] = '\0';
302 		p_err("can't mount BPF file system on given dir '%s': %s",
303 		      dir_name, err_str);
304 
305 		if (!dir_exists)
306 			rmdir(dir_name);
307 	}
308 
309 	return err;
310 }
311 
312 int mount_bpffs_for_file(const char *file_name)
313 {
314 	char err_str[ERR_MAX_LEN];
315 	char *temp_name;
316 	char *dir;
317 	int err = 0;
318 
319 	if (access(file_name, F_OK) != -1) {
320 		p_err("can't pin BPF object: path '%s' already exists", file_name);
321 		return -1;
322 	}
323 
324 	temp_name = strdup(file_name);
325 	if (!temp_name) {
326 		p_err("mem alloc failed");
327 		return -1;
328 	}
329 
330 	dir = dirname(temp_name);
331 
332 	if (is_bpffs(dir))
333 		/* nothing to do if already mounted */
334 		goto out_free;
335 
336 	if (access(dir, F_OK) == -1) {
337 		p_err("can't pin BPF object: dir '%s' doesn't exist", dir);
338 		err = -1;
339 		goto out_free;
340 	}
341 
342 	if (block_mount) {
343 		p_err("no BPF file system found, not mounting it due to --nomount option");
344 		err = -1;
345 		goto out_free;
346 	}
347 
348 	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
349 	if (err) {
350 		err_str[ERR_MAX_LEN - 1] = '\0';
351 		p_err("can't mount BPF file system to pin the object '%s': %s",
352 		      file_name, err_str);
353 	}
354 
355 out_free:
356 	free(temp_name);
357 	return err;
358 }
359 
360 int do_pin_fd(int fd, const char *name)
361 {
362 	int err;
363 
364 	err = mount_bpffs_for_file(name);
365 	if (err)
366 		return err;
367 
368 	err = bpf_obj_pin(fd, name);
369 	if (err)
370 		p_err("can't pin the object (%s): %s", name, strerror(errno));
371 
372 	return err;
373 }
374 
375 int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
376 {
377 	int err;
378 	int fd;
379 
380 	if (!REQ_ARGS(3))
381 		return -EINVAL;
382 
383 	fd = get_fd(&argc, &argv);
384 	if (fd < 0)
385 		return fd;
386 
387 	err = do_pin_fd(fd, *argv);
388 
389 	close(fd);
390 	return err;
391 }
392 
393 const char *get_fd_type_name(enum bpf_obj_type type)
394 {
395 	static const char * const names[] = {
396 		[BPF_OBJ_UNKNOWN]	= "unknown",
397 		[BPF_OBJ_PROG]		= "prog",
398 		[BPF_OBJ_MAP]		= "map",
399 		[BPF_OBJ_LINK]		= "link",
400 	};
401 
402 	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
403 		return names[BPF_OBJ_UNKNOWN];
404 
405 	return names[type];
406 }
407 
408 void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd,
409 			char *name_buff, size_t buff_len)
410 {
411 	const char *prog_name = prog_info->name;
412 	const struct btf_type *func_type;
413 	struct bpf_func_info finfo = {};
414 	struct bpf_prog_info info = {};
415 	__u32 info_len = sizeof(info);
416 	struct btf *prog_btf = NULL;
417 
418 	if (buff_len <= BPF_OBJ_NAME_LEN ||
419 	    strlen(prog_info->name) < BPF_OBJ_NAME_LEN - 1)
420 		goto copy_name;
421 
422 	if (!prog_info->btf_id || prog_info->nr_func_info == 0)
423 		goto copy_name;
424 
425 	info.nr_func_info = 1;
426 	info.func_info_rec_size = prog_info->func_info_rec_size;
427 	if (info.func_info_rec_size > sizeof(finfo))
428 		info.func_info_rec_size = sizeof(finfo);
429 	info.func_info = ptr_to_u64(&finfo);
430 
431 	if (bpf_prog_get_info_by_fd(prog_fd, &info, &info_len))
432 		goto copy_name;
433 
434 	prog_btf = btf__load_from_kernel_by_id(info.btf_id);
435 	if (!prog_btf)
436 		goto copy_name;
437 
438 	func_type = btf__type_by_id(prog_btf, finfo.type_id);
439 	if (!func_type || !btf_is_func(func_type))
440 		goto copy_name;
441 
442 	prog_name = btf__name_by_offset(prog_btf, func_type->name_off);
443 
444 copy_name:
445 	snprintf(name_buff, buff_len, "%s", prog_name);
446 
447 	if (prog_btf)
448 		btf__free(prog_btf);
449 }
450 
451 int get_fd_type(int fd)
452 {
453 	char path[PATH_MAX];
454 	char buf[512];
455 	ssize_t n;
456 
457 	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
458 
459 	n = readlink(path, buf, sizeof(buf));
460 	if (n < 0) {
461 		p_err("can't read link type: %s", strerror(errno));
462 		return -1;
463 	}
464 	if (n == sizeof(buf)) {
465 		p_err("can't read link type: path too long!");
466 		return -1;
467 	}
468 	buf[n] = '\0';
469 
470 	if (strstr(buf, "bpf-map"))
471 		return BPF_OBJ_MAP;
472 	else if (strstr(buf, "bpf-prog"))
473 		return BPF_OBJ_PROG;
474 	else if (strstr(buf, "bpf-link"))
475 		return BPF_OBJ_LINK;
476 
477 	return BPF_OBJ_UNKNOWN;
478 }
479 
480 char *get_fdinfo(int fd, const char *key)
481 {
482 	char path[PATH_MAX];
483 	char *line = NULL;
484 	size_t line_n = 0;
485 	ssize_t n;
486 	FILE *fdi;
487 
488 	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
489 
490 	fdi = fopen(path, "r");
491 	if (!fdi)
492 		return NULL;
493 
494 	while ((n = getline(&line, &line_n, fdi)) > 0) {
495 		char *value;
496 		int len;
497 
498 		if (!strstr(line, key))
499 			continue;
500 
501 		fclose(fdi);
502 
503 		value = strchr(line, '\t');
504 		if (!value || !value[1]) {
505 			free(line);
506 			return NULL;
507 		}
508 		value++;
509 
510 		len = strlen(value);
511 		memmove(line, value, len);
512 		line[len - 1] = '\0';
513 
514 		return line;
515 	}
516 
517 	free(line);
518 	fclose(fdi);
519 	return NULL;
520 }
521 
522 void print_data_json(uint8_t *data, size_t len)
523 {
524 	unsigned int i;
525 
526 	jsonw_start_array(json_wtr);
527 	for (i = 0; i < len; i++)
528 		jsonw_printf(json_wtr, "%d", data[i]);
529 	jsonw_end_array(json_wtr);
530 }
531 
532 void print_hex_data_json(uint8_t *data, size_t len)
533 {
534 	unsigned int i;
535 
536 	jsonw_start_array(json_wtr);
537 	for (i = 0; i < len; i++)
538 		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
539 	jsonw_end_array(json_wtr);
540 }
541 
542 /* extra params for nftw cb */
543 static struct hashmap *build_fn_table;
544 static enum bpf_obj_type build_fn_type;
545 
546 static int do_build_table_cb(const char *fpath, const struct stat *sb,
547 			     int typeflag, struct FTW *ftwbuf)
548 {
549 	struct bpf_prog_info pinned_info;
550 	__u32 len = sizeof(pinned_info);
551 	enum bpf_obj_type objtype;
552 	int fd, err = 0;
553 	char *path;
554 
555 	if (typeflag != FTW_F)
556 		goto out_ret;
557 
558 	fd = open_obj_pinned(fpath, true);
559 	if (fd < 0)
560 		goto out_ret;
561 
562 	objtype = get_fd_type(fd);
563 	if (objtype != build_fn_type)
564 		goto out_close;
565 
566 	memset(&pinned_info, 0, sizeof(pinned_info));
567 	if (bpf_prog_get_info_by_fd(fd, &pinned_info, &len))
568 		goto out_close;
569 
570 	path = strdup(fpath);
571 	if (!path) {
572 		err = -1;
573 		goto out_close;
574 	}
575 
576 	err = hashmap__append(build_fn_table, pinned_info.id, path);
577 	if (err) {
578 		p_err("failed to append entry to hashmap for ID %u, path '%s': %s",
579 		      pinned_info.id, path, strerror(errno));
580 		free(path);
581 		goto out_close;
582 	}
583 
584 out_close:
585 	close(fd);
586 out_ret:
587 	return err;
588 }
589 
590 int build_pinned_obj_table(struct hashmap *tab,
591 			   enum bpf_obj_type type)
592 {
593 	struct mntent *mntent = NULL;
594 	FILE *mntfile = NULL;
595 	int flags = FTW_PHYS;
596 	int nopenfd = 16;
597 	int err = 0;
598 
599 	mntfile = setmntent("/proc/mounts", "r");
600 	if (!mntfile)
601 		return -1;
602 
603 	build_fn_table = tab;
604 	build_fn_type = type;
605 
606 	while ((mntent = getmntent(mntfile))) {
607 		char *path = mntent->mnt_dir;
608 
609 		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
610 			continue;
611 		err = nftw(path, do_build_table_cb, nopenfd, flags);
612 		if (err)
613 			break;
614 	}
615 	fclose(mntfile);
616 	return err;
617 }
618 
619 void delete_pinned_obj_table(struct hashmap *map)
620 {
621 	struct hashmap_entry *entry;
622 	size_t bkt;
623 
624 	if (!map)
625 		return;
626 
627 	hashmap__for_each_entry(map, entry, bkt)
628 		free(entry->pvalue);
629 
630 	hashmap__free(map);
631 }
632 
633 unsigned int get_page_size(void)
634 {
635 	static int result;
636 
637 	if (!result)
638 		result = getpagesize();
639 	return result;
640 }
641 
642 unsigned int get_possible_cpus(void)
643 {
644 	int cpus = libbpf_num_possible_cpus();
645 
646 	if (cpus < 0) {
647 		p_err("Can't get # of possible cpus: %s", strerror(-cpus));
648 		exit(-1);
649 	}
650 	return cpus;
651 }
652 
653 static char *
654 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
655 {
656 	struct stat st;
657 	int err;
658 
659 	err = stat("/proc/self/ns/net", &st);
660 	if (err) {
661 		p_err("Can't stat /proc/self: %s", strerror(errno));
662 		return NULL;
663 	}
664 
665 	if (st.st_dev != ns_dev || st.st_ino != ns_ino)
666 		return NULL;
667 
668 	return if_indextoname(ifindex, buf);
669 }
670 
671 static int read_sysfs_hex_int(char *path)
672 {
673 	char vendor_id_buf[8];
674 	int len;
675 	int fd;
676 
677 	fd = open(path, O_RDONLY);
678 	if (fd < 0) {
679 		p_err("Can't open %s: %s", path, strerror(errno));
680 		return -1;
681 	}
682 
683 	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
684 	close(fd);
685 	if (len < 0) {
686 		p_err("Can't read %s: %s", path, strerror(errno));
687 		return -1;
688 	}
689 	if (len >= (int)sizeof(vendor_id_buf)) {
690 		p_err("Value in %s too long", path);
691 		return -1;
692 	}
693 
694 	vendor_id_buf[len] = 0;
695 
696 	return strtol(vendor_id_buf, NULL, 0);
697 }
698 
699 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
700 {
701 	char full_path[64];
702 
703 	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
704 		 devname, entry_name);
705 
706 	return read_sysfs_hex_int(full_path);
707 }
708 
709 const char *
710 ifindex_to_arch(__u32 ifindex, __u64 ns_dev, __u64 ns_ino, const char **opt)
711 {
712 	__maybe_unused int device_id;
713 	char devname[IF_NAMESIZE];
714 	int vendor_id;
715 
716 	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
717 		p_err("Can't get net device name for ifindex %u: %s", ifindex,
718 		      strerror(errno));
719 		return NULL;
720 	}
721 
722 	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
723 	if (vendor_id < 0) {
724 		p_err("Can't get device vendor id for %s", devname);
725 		return NULL;
726 	}
727 
728 	switch (vendor_id) {
729 #ifdef HAVE_LIBBFD_SUPPORT
730 	case 0x19ee:
731 		device_id = read_sysfs_netdev_hex_int(devname, "device");
732 		if (device_id != 0x4000 &&
733 		    device_id != 0x6000 &&
734 		    device_id != 0x6003)
735 			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
736 		*opt = "ctx4";
737 		return "NFP-6xxx";
738 #endif /* HAVE_LIBBFD_SUPPORT */
739 	/* No NFP support in LLVM, we have no valid triple to return. */
740 	default:
741 		p_err("Can't get arch name for device vendor id 0x%04x",
742 		      (unsigned int)vendor_id);
743 		return NULL;
744 	}
745 }
746 
747 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
748 {
749 	char name[IF_NAMESIZE];
750 
751 	if (!ifindex)
752 		return;
753 
754 	printf("  offloaded_to ");
755 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
756 		printf("%s", name);
757 	else
758 		printf("ifindex %u ns_dev %llu ns_ino %llu",
759 		       ifindex, ns_dev, ns_inode);
760 }
761 
762 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
763 {
764 	char name[IF_NAMESIZE];
765 
766 	if (!ifindex)
767 		return;
768 
769 	jsonw_name(json_wtr, "dev");
770 	jsonw_start_object(json_wtr);
771 	jsonw_uint_field(json_wtr, "ifindex", ifindex);
772 	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
773 	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
774 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
775 		jsonw_string_field(json_wtr, "ifname", name);
776 	jsonw_end_object(json_wtr);
777 }
778 
779 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
780 {
781 	char *endptr;
782 
783 	NEXT_ARGP();
784 
785 	if (*val) {
786 		p_err("%s already specified", what);
787 		return -1;
788 	}
789 
790 	*val = strtoul(**argv, &endptr, 0);
791 	if (*endptr) {
792 		p_err("can't parse %s as %s", **argv, what);
793 		return -1;
794 	}
795 	NEXT_ARGP();
796 
797 	return 0;
798 }
799 
800 int __printf(2, 0)
801 print_all_levels(__maybe_unused enum libbpf_print_level level,
802 		 const char *format, va_list args)
803 {
804 	return vfprintf(stderr, format, args);
805 }
806 
807 static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
808 {
809 	char prog_name[MAX_PROG_FULL_NAME];
810 	unsigned int id = 0;
811 	int fd, nb_fds = 0;
812 	void *tmp;
813 	int err;
814 
815 	while (true) {
816 		struct bpf_prog_info info = {};
817 		__u32 len = sizeof(info);
818 
819 		err = bpf_prog_get_next_id(id, &id);
820 		if (err) {
821 			if (errno != ENOENT) {
822 				p_err("%s", strerror(errno));
823 				goto err_close_fds;
824 			}
825 			return nb_fds;
826 		}
827 
828 		fd = bpf_prog_get_fd_by_id(id);
829 		if (fd < 0) {
830 			p_err("can't get prog by id (%u): %s",
831 			      id, strerror(errno));
832 			goto err_close_fds;
833 		}
834 
835 		err = bpf_prog_get_info_by_fd(fd, &info, &len);
836 		if (err) {
837 			p_err("can't get prog info (%u): %s",
838 			      id, strerror(errno));
839 			goto err_close_fd;
840 		}
841 
842 		if (tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) {
843 			close(fd);
844 			continue;
845 		}
846 
847 		if (!tag) {
848 			get_prog_full_name(&info, fd, prog_name,
849 					   sizeof(prog_name));
850 			if (strncmp(nametag, prog_name, sizeof(prog_name))) {
851 				close(fd);
852 				continue;
853 			}
854 		}
855 
856 		if (nb_fds > 0) {
857 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
858 			if (!tmp) {
859 				p_err("failed to realloc");
860 				goto err_close_fd;
861 			}
862 			*fds = tmp;
863 		}
864 		(*fds)[nb_fds++] = fd;
865 	}
866 
867 err_close_fd:
868 	close(fd);
869 err_close_fds:
870 	while (--nb_fds >= 0)
871 		close((*fds)[nb_fds]);
872 	return -1;
873 }
874 
875 int prog_parse_fds(int *argc, char ***argv, int **fds)
876 {
877 	if (is_prefix(**argv, "id")) {
878 		unsigned int id;
879 		char *endptr;
880 
881 		NEXT_ARGP();
882 
883 		id = strtoul(**argv, &endptr, 0);
884 		if (*endptr) {
885 			p_err("can't parse %s as ID", **argv);
886 			return -1;
887 		}
888 		NEXT_ARGP();
889 
890 		(*fds)[0] = bpf_prog_get_fd_by_id(id);
891 		if ((*fds)[0] < 0) {
892 			p_err("get by id (%u): %s", id, strerror(errno));
893 			return -1;
894 		}
895 		return 1;
896 	} else if (is_prefix(**argv, "tag")) {
897 		unsigned char tag[BPF_TAG_SIZE];
898 
899 		NEXT_ARGP();
900 
901 		if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
902 			   tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
903 		    != BPF_TAG_SIZE) {
904 			p_err("can't parse tag");
905 			return -1;
906 		}
907 		NEXT_ARGP();
908 
909 		return prog_fd_by_nametag(tag, fds, true);
910 	} else if (is_prefix(**argv, "name")) {
911 		char *name;
912 
913 		NEXT_ARGP();
914 
915 		name = **argv;
916 		if (strlen(name) > MAX_PROG_FULL_NAME - 1) {
917 			p_err("can't parse name");
918 			return -1;
919 		}
920 		NEXT_ARGP();
921 
922 		return prog_fd_by_nametag(name, fds, false);
923 	} else if (is_prefix(**argv, "pinned")) {
924 		char *path;
925 
926 		NEXT_ARGP();
927 
928 		path = **argv;
929 		NEXT_ARGP();
930 
931 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
932 		if ((*fds)[0] < 0)
933 			return -1;
934 		return 1;
935 	}
936 
937 	p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
938 	return -1;
939 }
940 
941 int prog_parse_fd(int *argc, char ***argv)
942 {
943 	int *fds = NULL;
944 	int nb_fds, fd;
945 
946 	fds = malloc(sizeof(int));
947 	if (!fds) {
948 		p_err("mem alloc failed");
949 		return -1;
950 	}
951 	nb_fds = prog_parse_fds(argc, argv, &fds);
952 	if (nb_fds != 1) {
953 		if (nb_fds > 1) {
954 			p_err("several programs match this handle");
955 			while (nb_fds--)
956 				close(fds[nb_fds]);
957 		}
958 		fd = -1;
959 		goto exit_free;
960 	}
961 
962 	fd = fds[0];
963 exit_free:
964 	free(fds);
965 	return fd;
966 }
967 
968 static int map_fd_by_name(char *name, int **fds)
969 {
970 	unsigned int id = 0;
971 	int fd, nb_fds = 0;
972 	void *tmp;
973 	int err;
974 
975 	while (true) {
976 		struct bpf_map_info info = {};
977 		__u32 len = sizeof(info);
978 
979 		err = bpf_map_get_next_id(id, &id);
980 		if (err) {
981 			if (errno != ENOENT) {
982 				p_err("%s", strerror(errno));
983 				goto err_close_fds;
984 			}
985 			return nb_fds;
986 		}
987 
988 		fd = bpf_map_get_fd_by_id(id);
989 		if (fd < 0) {
990 			p_err("can't get map by id (%u): %s",
991 			      id, strerror(errno));
992 			goto err_close_fds;
993 		}
994 
995 		err = bpf_map_get_info_by_fd(fd, &info, &len);
996 		if (err) {
997 			p_err("can't get map info (%u): %s",
998 			      id, strerror(errno));
999 			goto err_close_fd;
1000 		}
1001 
1002 		if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
1003 			close(fd);
1004 			continue;
1005 		}
1006 
1007 		if (nb_fds > 0) {
1008 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
1009 			if (!tmp) {
1010 				p_err("failed to realloc");
1011 				goto err_close_fd;
1012 			}
1013 			*fds = tmp;
1014 		}
1015 		(*fds)[nb_fds++] = fd;
1016 	}
1017 
1018 err_close_fd:
1019 	close(fd);
1020 err_close_fds:
1021 	while (--nb_fds >= 0)
1022 		close((*fds)[nb_fds]);
1023 	return -1;
1024 }
1025 
1026 int map_parse_fds(int *argc, char ***argv, int **fds)
1027 {
1028 	if (is_prefix(**argv, "id")) {
1029 		unsigned int id;
1030 		char *endptr;
1031 
1032 		NEXT_ARGP();
1033 
1034 		id = strtoul(**argv, &endptr, 0);
1035 		if (*endptr) {
1036 			p_err("can't parse %s as ID", **argv);
1037 			return -1;
1038 		}
1039 		NEXT_ARGP();
1040 
1041 		(*fds)[0] = bpf_map_get_fd_by_id(id);
1042 		if ((*fds)[0] < 0) {
1043 			p_err("get map by id (%u): %s", id, strerror(errno));
1044 			return -1;
1045 		}
1046 		return 1;
1047 	} else if (is_prefix(**argv, "name")) {
1048 		char *name;
1049 
1050 		NEXT_ARGP();
1051 
1052 		name = **argv;
1053 		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
1054 			p_err("can't parse name");
1055 			return -1;
1056 		}
1057 		NEXT_ARGP();
1058 
1059 		return map_fd_by_name(name, fds);
1060 	} else if (is_prefix(**argv, "pinned")) {
1061 		char *path;
1062 
1063 		NEXT_ARGP();
1064 
1065 		path = **argv;
1066 		NEXT_ARGP();
1067 
1068 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
1069 		if ((*fds)[0] < 0)
1070 			return -1;
1071 		return 1;
1072 	}
1073 
1074 	p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
1075 	return -1;
1076 }
1077 
1078 int map_parse_fd(int *argc, char ***argv)
1079 {
1080 	int *fds = NULL;
1081 	int nb_fds, fd;
1082 
1083 	fds = malloc(sizeof(int));
1084 	if (!fds) {
1085 		p_err("mem alloc failed");
1086 		return -1;
1087 	}
1088 	nb_fds = map_parse_fds(argc, argv, &fds);
1089 	if (nb_fds != 1) {
1090 		if (nb_fds > 1) {
1091 			p_err("several maps match this handle");
1092 			while (nb_fds--)
1093 				close(fds[nb_fds]);
1094 		}
1095 		fd = -1;
1096 		goto exit_free;
1097 	}
1098 
1099 	fd = fds[0];
1100 exit_free:
1101 	free(fds);
1102 	return fd;
1103 }
1104 
1105 int map_parse_fd_and_info(int *argc, char ***argv, struct bpf_map_info *info,
1106 			  __u32 *info_len)
1107 {
1108 	int err;
1109 	int fd;
1110 
1111 	fd = map_parse_fd(argc, argv);
1112 	if (fd < 0)
1113 		return -1;
1114 
1115 	err = bpf_map_get_info_by_fd(fd, info, info_len);
1116 	if (err) {
1117 		p_err("can't get map info: %s", strerror(errno));
1118 		close(fd);
1119 		return err;
1120 	}
1121 
1122 	return fd;
1123 }
1124 
1125 size_t hash_fn_for_key_as_id(long key, void *ctx)
1126 {
1127 	return key;
1128 }
1129 
1130 bool equal_fn_for_key_as_id(long k1, long k2, void *ctx)
1131 {
1132 	return k1 == k2;
1133 }
1134 
1135 const char *bpf_attach_type_input_str(enum bpf_attach_type t)
1136 {
1137 	switch (t) {
1138 	case BPF_CGROUP_INET_INGRESS:		return "ingress";
1139 	case BPF_CGROUP_INET_EGRESS:		return "egress";
1140 	case BPF_CGROUP_INET_SOCK_CREATE:	return "sock_create";
1141 	case BPF_CGROUP_INET_SOCK_RELEASE:	return "sock_release";
1142 	case BPF_CGROUP_SOCK_OPS:		return "sock_ops";
1143 	case BPF_CGROUP_DEVICE:			return "device";
1144 	case BPF_CGROUP_INET4_BIND:		return "bind4";
1145 	case BPF_CGROUP_INET6_BIND:		return "bind6";
1146 	case BPF_CGROUP_INET4_CONNECT:		return "connect4";
1147 	case BPF_CGROUP_INET6_CONNECT:		return "connect6";
1148 	case BPF_CGROUP_INET4_POST_BIND:	return "post_bind4";
1149 	case BPF_CGROUP_INET6_POST_BIND:	return "post_bind6";
1150 	case BPF_CGROUP_INET4_GETPEERNAME:	return "getpeername4";
1151 	case BPF_CGROUP_INET6_GETPEERNAME:	return "getpeername6";
1152 	case BPF_CGROUP_INET4_GETSOCKNAME:	return "getsockname4";
1153 	case BPF_CGROUP_INET6_GETSOCKNAME:	return "getsockname6";
1154 	case BPF_CGROUP_UDP4_SENDMSG:		return "sendmsg4";
1155 	case BPF_CGROUP_UDP6_SENDMSG:		return "sendmsg6";
1156 	case BPF_CGROUP_SYSCTL:			return "sysctl";
1157 	case BPF_CGROUP_UDP4_RECVMSG:		return "recvmsg4";
1158 	case BPF_CGROUP_UDP6_RECVMSG:		return "recvmsg6";
1159 	case BPF_CGROUP_GETSOCKOPT:		return "getsockopt";
1160 	case BPF_CGROUP_SETSOCKOPT:		return "setsockopt";
1161 	case BPF_TRACE_RAW_TP:			return "raw_tp";
1162 	case BPF_TRACE_FENTRY:			return "fentry";
1163 	case BPF_TRACE_FEXIT:			return "fexit";
1164 	case BPF_MODIFY_RETURN:			return "mod_ret";
1165 	case BPF_SK_REUSEPORT_SELECT:		return "sk_skb_reuseport_select";
1166 	case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:	return "sk_skb_reuseport_select_or_migrate";
1167 	default:	return libbpf_bpf_attach_type_str(t);
1168 	}
1169 }
1170 
1171 int pathname_concat(char *buf, int buf_sz, const char *path,
1172 		    const char *name)
1173 {
1174 	int len;
1175 
1176 	len = snprintf(buf, buf_sz, "%s/%s", path, name);
1177 	if (len < 0)
1178 		return -EINVAL;
1179 	if (len >= buf_sz)
1180 		return -ENAMETOOLONG;
1181 
1182 	return 0;
1183 }
1184