xref: /linux/tools/bpf/bpftool/common.c (revision 64b14a184e83eb62ea0615e31a409956049d40e7)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2017-2018 Netronome Systems, Inc. */
3 
4 #define _GNU_SOURCE
5 #include <ctype.h>
6 #include <errno.h>
7 #include <fcntl.h>
8 #include <ftw.h>
9 #include <libgen.h>
10 #include <mntent.h>
11 #include <stdbool.h>
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <string.h>
15 #include <unistd.h>
16 #include <linux/limits.h>
17 #include <linux/magic.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 <bpf/bpf.h>
25 #include <bpf/hashmap.h>
26 #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
27 
28 #include "main.h"
29 
30 #ifndef BPF_FS_MAGIC
31 #define BPF_FS_MAGIC		0xcafe4a11
32 #endif
33 
34 const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = {
35 	[BPF_CGROUP_INET_INGRESS]	= "ingress",
36 	[BPF_CGROUP_INET_EGRESS]	= "egress",
37 	[BPF_CGROUP_INET_SOCK_CREATE]	= "sock_create",
38 	[BPF_CGROUP_INET_SOCK_RELEASE]	= "sock_release",
39 	[BPF_CGROUP_SOCK_OPS]		= "sock_ops",
40 	[BPF_CGROUP_DEVICE]		= "device",
41 	[BPF_CGROUP_INET4_BIND]		= "bind4",
42 	[BPF_CGROUP_INET6_BIND]		= "bind6",
43 	[BPF_CGROUP_INET4_CONNECT]	= "connect4",
44 	[BPF_CGROUP_INET6_CONNECT]	= "connect6",
45 	[BPF_CGROUP_INET4_POST_BIND]	= "post_bind4",
46 	[BPF_CGROUP_INET6_POST_BIND]	= "post_bind6",
47 	[BPF_CGROUP_INET4_GETPEERNAME]	= "getpeername4",
48 	[BPF_CGROUP_INET6_GETPEERNAME]	= "getpeername6",
49 	[BPF_CGROUP_INET4_GETSOCKNAME]	= "getsockname4",
50 	[BPF_CGROUP_INET6_GETSOCKNAME]	= "getsockname6",
51 	[BPF_CGROUP_UDP4_SENDMSG]	= "sendmsg4",
52 	[BPF_CGROUP_UDP6_SENDMSG]	= "sendmsg6",
53 	[BPF_CGROUP_SYSCTL]		= "sysctl",
54 	[BPF_CGROUP_UDP4_RECVMSG]	= "recvmsg4",
55 	[BPF_CGROUP_UDP6_RECVMSG]	= "recvmsg6",
56 	[BPF_CGROUP_GETSOCKOPT]		= "getsockopt",
57 	[BPF_CGROUP_SETSOCKOPT]		= "setsockopt",
58 
59 	[BPF_SK_SKB_STREAM_PARSER]	= "sk_skb_stream_parser",
60 	[BPF_SK_SKB_STREAM_VERDICT]	= "sk_skb_stream_verdict",
61 	[BPF_SK_SKB_VERDICT]		= "sk_skb_verdict",
62 	[BPF_SK_MSG_VERDICT]		= "sk_msg_verdict",
63 	[BPF_LIRC_MODE2]		= "lirc_mode2",
64 	[BPF_FLOW_DISSECTOR]		= "flow_dissector",
65 	[BPF_TRACE_RAW_TP]		= "raw_tp",
66 	[BPF_TRACE_FENTRY]		= "fentry",
67 	[BPF_TRACE_FEXIT]		= "fexit",
68 	[BPF_MODIFY_RETURN]		= "mod_ret",
69 	[BPF_LSM_MAC]			= "lsm_mac",
70 	[BPF_SK_LOOKUP]			= "sk_lookup",
71 	[BPF_TRACE_ITER]		= "trace_iter",
72 	[BPF_XDP_DEVMAP]		= "xdp_devmap",
73 	[BPF_XDP_CPUMAP]		= "xdp_cpumap",
74 	[BPF_XDP]			= "xdp",
75 	[BPF_SK_REUSEPORT_SELECT]	= "sk_skb_reuseport_select",
76 	[BPF_SK_REUSEPORT_SELECT_OR_MIGRATE]	= "sk_skb_reuseport_select_or_migrate",
77 	[BPF_PERF_EVENT]		= "perf_event",
78 };
79 
80 void p_err(const char *fmt, ...)
81 {
82 	va_list ap;
83 
84 	va_start(ap, fmt);
85 	if (json_output) {
86 		jsonw_start_object(json_wtr);
87 		jsonw_name(json_wtr, "error");
88 		jsonw_vprintf_enquote(json_wtr, fmt, ap);
89 		jsonw_end_object(json_wtr);
90 	} else {
91 		fprintf(stderr, "Error: ");
92 		vfprintf(stderr, fmt, ap);
93 		fprintf(stderr, "\n");
94 	}
95 	va_end(ap);
96 }
97 
98 void p_info(const char *fmt, ...)
99 {
100 	va_list ap;
101 
102 	if (json_output)
103 		return;
104 
105 	va_start(ap, fmt);
106 	vfprintf(stderr, fmt, ap);
107 	fprintf(stderr, "\n");
108 	va_end(ap);
109 }
110 
111 static bool is_bpffs(char *path)
112 {
113 	struct statfs st_fs;
114 
115 	if (statfs(path, &st_fs) < 0)
116 		return false;
117 
118 	return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
119 }
120 
121 void set_max_rlimit(void)
122 {
123 	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
124 
125 	setrlimit(RLIMIT_MEMLOCK, &rinf);
126 }
127 
128 static int
129 mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
130 {
131 	bool bind_done = false;
132 
133 	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
134 		if (errno != EINVAL || bind_done) {
135 			snprintf(buff, bufflen,
136 				 "mount --make-private %s failed: %s",
137 				 target, strerror(errno));
138 			return -1;
139 		}
140 
141 		if (mount(target, target, "none", MS_BIND, NULL)) {
142 			snprintf(buff, bufflen,
143 				 "mount --bind %s %s failed: %s",
144 				 target, target, strerror(errno));
145 			return -1;
146 		}
147 
148 		bind_done = true;
149 	}
150 
151 	if (mount(type, target, type, 0, "mode=0700")) {
152 		snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
153 			 type, type, target, strerror(errno));
154 		return -1;
155 	}
156 
157 	return 0;
158 }
159 
160 int mount_tracefs(const char *target)
161 {
162 	char err_str[ERR_MAX_LEN];
163 	int err;
164 
165 	err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
166 	if (err) {
167 		err_str[ERR_MAX_LEN - 1] = '\0';
168 		p_err("can't mount tracefs: %s", err_str);
169 	}
170 
171 	return err;
172 }
173 
174 int open_obj_pinned(const char *path, bool quiet)
175 {
176 	char *pname;
177 	int fd = -1;
178 
179 	pname = strdup(path);
180 	if (!pname) {
181 		if (!quiet)
182 			p_err("mem alloc failed");
183 		goto out_ret;
184 	}
185 
186 	fd = bpf_obj_get(pname);
187 	if (fd < 0) {
188 		if (!quiet)
189 			p_err("bpf obj get (%s): %s", pname,
190 			      errno == EACCES && !is_bpffs(dirname(pname)) ?
191 			    "directory not in bpf file system (bpffs)" :
192 			    strerror(errno));
193 		goto out_free;
194 	}
195 
196 out_free:
197 	free(pname);
198 out_ret:
199 	return fd;
200 }
201 
202 int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)
203 {
204 	enum bpf_obj_type type;
205 	int fd;
206 
207 	fd = open_obj_pinned(path, false);
208 	if (fd < 0)
209 		return -1;
210 
211 	type = get_fd_type(fd);
212 	if (type < 0) {
213 		close(fd);
214 		return type;
215 	}
216 	if (type != exp_type) {
217 		p_err("incorrect object type: %s", get_fd_type_name(type));
218 		close(fd);
219 		return -1;
220 	}
221 
222 	return fd;
223 }
224 
225 int mount_bpffs_for_pin(const char *name)
226 {
227 	char err_str[ERR_MAX_LEN];
228 	char *file;
229 	char *dir;
230 	int err = 0;
231 
232 	file = malloc(strlen(name) + 1);
233 	if (!file) {
234 		p_err("mem alloc failed");
235 		return -1;
236 	}
237 
238 	strcpy(file, name);
239 	dir = dirname(file);
240 
241 	if (is_bpffs(dir))
242 		/* nothing to do if already mounted */
243 		goto out_free;
244 
245 	if (block_mount) {
246 		p_err("no BPF file system found, not mounting it due to --nomount option");
247 		err = -1;
248 		goto out_free;
249 	}
250 
251 	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
252 	if (err) {
253 		err_str[ERR_MAX_LEN - 1] = '\0';
254 		p_err("can't mount BPF file system to pin the object (%s): %s",
255 		      name, err_str);
256 	}
257 
258 out_free:
259 	free(file);
260 	return err;
261 }
262 
263 int do_pin_fd(int fd, const char *name)
264 {
265 	int err;
266 
267 	err = mount_bpffs_for_pin(name);
268 	if (err)
269 		return err;
270 
271 	err = bpf_obj_pin(fd, name);
272 	if (err)
273 		p_err("can't pin the object (%s): %s", name, strerror(errno));
274 
275 	return err;
276 }
277 
278 int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
279 {
280 	int err;
281 	int fd;
282 
283 	fd = get_fd(&argc, &argv);
284 	if (fd < 0)
285 		return fd;
286 
287 	err = do_pin_fd(fd, *argv);
288 
289 	close(fd);
290 	return err;
291 }
292 
293 const char *get_fd_type_name(enum bpf_obj_type type)
294 {
295 	static const char * const names[] = {
296 		[BPF_OBJ_UNKNOWN]	= "unknown",
297 		[BPF_OBJ_PROG]		= "prog",
298 		[BPF_OBJ_MAP]		= "map",
299 	};
300 
301 	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
302 		return names[BPF_OBJ_UNKNOWN];
303 
304 	return names[type];
305 }
306 
307 int get_fd_type(int fd)
308 {
309 	char path[PATH_MAX];
310 	char buf[512];
311 	ssize_t n;
312 
313 	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
314 
315 	n = readlink(path, buf, sizeof(buf));
316 	if (n < 0) {
317 		p_err("can't read link type: %s", strerror(errno));
318 		return -1;
319 	}
320 	if (n == sizeof(path)) {
321 		p_err("can't read link type: path too long!");
322 		return -1;
323 	}
324 
325 	if (strstr(buf, "bpf-map"))
326 		return BPF_OBJ_MAP;
327 	else if (strstr(buf, "bpf-prog"))
328 		return BPF_OBJ_PROG;
329 	else if (strstr(buf, "bpf-link"))
330 		return BPF_OBJ_LINK;
331 
332 	return BPF_OBJ_UNKNOWN;
333 }
334 
335 char *get_fdinfo(int fd, const char *key)
336 {
337 	char path[PATH_MAX];
338 	char *line = NULL;
339 	size_t line_n = 0;
340 	ssize_t n;
341 	FILE *fdi;
342 
343 	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
344 
345 	fdi = fopen(path, "r");
346 	if (!fdi)
347 		return NULL;
348 
349 	while ((n = getline(&line, &line_n, fdi)) > 0) {
350 		char *value;
351 		int len;
352 
353 		if (!strstr(line, key))
354 			continue;
355 
356 		fclose(fdi);
357 
358 		value = strchr(line, '\t');
359 		if (!value || !value[1]) {
360 			free(line);
361 			return NULL;
362 		}
363 		value++;
364 
365 		len = strlen(value);
366 		memmove(line, value, len);
367 		line[len - 1] = '\0';
368 
369 		return line;
370 	}
371 
372 	free(line);
373 	fclose(fdi);
374 	return NULL;
375 }
376 
377 void print_data_json(uint8_t *data, size_t len)
378 {
379 	unsigned int i;
380 
381 	jsonw_start_array(json_wtr);
382 	for (i = 0; i < len; i++)
383 		jsonw_printf(json_wtr, "%d", data[i]);
384 	jsonw_end_array(json_wtr);
385 }
386 
387 void print_hex_data_json(uint8_t *data, size_t len)
388 {
389 	unsigned int i;
390 
391 	jsonw_start_array(json_wtr);
392 	for (i = 0; i < len; i++)
393 		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
394 	jsonw_end_array(json_wtr);
395 }
396 
397 /* extra params for nftw cb */
398 static struct hashmap *build_fn_table;
399 static enum bpf_obj_type build_fn_type;
400 
401 static int do_build_table_cb(const char *fpath, const struct stat *sb,
402 			     int typeflag, struct FTW *ftwbuf)
403 {
404 	struct bpf_prog_info pinned_info;
405 	__u32 len = sizeof(pinned_info);
406 	enum bpf_obj_type objtype;
407 	int fd, err = 0;
408 	char *path;
409 
410 	if (typeflag != FTW_F)
411 		goto out_ret;
412 
413 	fd = open_obj_pinned(fpath, true);
414 	if (fd < 0)
415 		goto out_ret;
416 
417 	objtype = get_fd_type(fd);
418 	if (objtype != build_fn_type)
419 		goto out_close;
420 
421 	memset(&pinned_info, 0, sizeof(pinned_info));
422 	if (bpf_obj_get_info_by_fd(fd, &pinned_info, &len))
423 		goto out_close;
424 
425 	path = strdup(fpath);
426 	if (!path) {
427 		err = -1;
428 		goto out_close;
429 	}
430 
431 	err = hashmap__append(build_fn_table, u32_as_hash_field(pinned_info.id), path);
432 	if (err) {
433 		p_err("failed to append entry to hashmap for ID %u, path '%s': %s",
434 		      pinned_info.id, path, strerror(errno));
435 		goto out_close;
436 	}
437 
438 out_close:
439 	close(fd);
440 out_ret:
441 	return err;
442 }
443 
444 int build_pinned_obj_table(struct hashmap *tab,
445 			   enum bpf_obj_type type)
446 {
447 	struct mntent *mntent = NULL;
448 	FILE *mntfile = NULL;
449 	int flags = FTW_PHYS;
450 	int nopenfd = 16;
451 	int err = 0;
452 
453 	mntfile = setmntent("/proc/mounts", "r");
454 	if (!mntfile)
455 		return -1;
456 
457 	build_fn_table = tab;
458 	build_fn_type = type;
459 
460 	while ((mntent = getmntent(mntfile))) {
461 		char *path = mntent->mnt_dir;
462 
463 		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
464 			continue;
465 		err = nftw(path, do_build_table_cb, nopenfd, flags);
466 		if (err)
467 			break;
468 	}
469 	fclose(mntfile);
470 	return err;
471 }
472 
473 void delete_pinned_obj_table(struct hashmap *map)
474 {
475 	struct hashmap_entry *entry;
476 	size_t bkt;
477 
478 	if (!map)
479 		return;
480 
481 	hashmap__for_each_entry(map, entry, bkt)
482 		free(entry->value);
483 
484 	hashmap__free(map);
485 }
486 
487 unsigned int get_page_size(void)
488 {
489 	static int result;
490 
491 	if (!result)
492 		result = getpagesize();
493 	return result;
494 }
495 
496 unsigned int get_possible_cpus(void)
497 {
498 	int cpus = libbpf_num_possible_cpus();
499 
500 	if (cpus < 0) {
501 		p_err("Can't get # of possible cpus: %s", strerror(-cpus));
502 		exit(-1);
503 	}
504 	return cpus;
505 }
506 
507 static char *
508 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
509 {
510 	struct stat st;
511 	int err;
512 
513 	err = stat("/proc/self/ns/net", &st);
514 	if (err) {
515 		p_err("Can't stat /proc/self: %s", strerror(errno));
516 		return NULL;
517 	}
518 
519 	if (st.st_dev != ns_dev || st.st_ino != ns_ino)
520 		return NULL;
521 
522 	return if_indextoname(ifindex, buf);
523 }
524 
525 static int read_sysfs_hex_int(char *path)
526 {
527 	char vendor_id_buf[8];
528 	int len;
529 	int fd;
530 
531 	fd = open(path, O_RDONLY);
532 	if (fd < 0) {
533 		p_err("Can't open %s: %s", path, strerror(errno));
534 		return -1;
535 	}
536 
537 	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
538 	close(fd);
539 	if (len < 0) {
540 		p_err("Can't read %s: %s", path, strerror(errno));
541 		return -1;
542 	}
543 	if (len >= (int)sizeof(vendor_id_buf)) {
544 		p_err("Value in %s too long", path);
545 		return -1;
546 	}
547 
548 	vendor_id_buf[len] = 0;
549 
550 	return strtol(vendor_id_buf, NULL, 0);
551 }
552 
553 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
554 {
555 	char full_path[64];
556 
557 	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
558 		 devname, entry_name);
559 
560 	return read_sysfs_hex_int(full_path);
561 }
562 
563 const char *
564 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
565 		      const char **opt)
566 {
567 	char devname[IF_NAMESIZE];
568 	int vendor_id;
569 	int device_id;
570 
571 	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
572 		p_err("Can't get net device name for ifindex %d: %s", ifindex,
573 		      strerror(errno));
574 		return NULL;
575 	}
576 
577 	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
578 	if (vendor_id < 0) {
579 		p_err("Can't get device vendor id for %s", devname);
580 		return NULL;
581 	}
582 
583 	switch (vendor_id) {
584 	case 0x19ee:
585 		device_id = read_sysfs_netdev_hex_int(devname, "device");
586 		if (device_id != 0x4000 &&
587 		    device_id != 0x6000 &&
588 		    device_id != 0x6003)
589 			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
590 		*opt = "ctx4";
591 		return "NFP-6xxx";
592 	default:
593 		p_err("Can't get bfd arch name for device vendor id 0x%04x",
594 		      vendor_id);
595 		return NULL;
596 	}
597 }
598 
599 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
600 {
601 	char name[IF_NAMESIZE];
602 
603 	if (!ifindex)
604 		return;
605 
606 	printf("  offloaded_to ");
607 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
608 		printf("%s", name);
609 	else
610 		printf("ifindex %u ns_dev %llu ns_ino %llu",
611 		       ifindex, ns_dev, ns_inode);
612 }
613 
614 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
615 {
616 	char name[IF_NAMESIZE];
617 
618 	if (!ifindex)
619 		return;
620 
621 	jsonw_name(json_wtr, "dev");
622 	jsonw_start_object(json_wtr);
623 	jsonw_uint_field(json_wtr, "ifindex", ifindex);
624 	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
625 	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
626 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
627 		jsonw_string_field(json_wtr, "ifname", name);
628 	jsonw_end_object(json_wtr);
629 }
630 
631 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
632 {
633 	char *endptr;
634 
635 	NEXT_ARGP();
636 
637 	if (*val) {
638 		p_err("%s already specified", what);
639 		return -1;
640 	}
641 
642 	*val = strtoul(**argv, &endptr, 0);
643 	if (*endptr) {
644 		p_err("can't parse %s as %s", **argv, what);
645 		return -1;
646 	}
647 	NEXT_ARGP();
648 
649 	return 0;
650 }
651 
652 int __printf(2, 0)
653 print_all_levels(__maybe_unused enum libbpf_print_level level,
654 		 const char *format, va_list args)
655 {
656 	return vfprintf(stderr, format, args);
657 }
658 
659 static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
660 {
661 	unsigned int id = 0;
662 	int fd, nb_fds = 0;
663 	void *tmp;
664 	int err;
665 
666 	while (true) {
667 		struct bpf_prog_info info = {};
668 		__u32 len = sizeof(info);
669 
670 		err = bpf_prog_get_next_id(id, &id);
671 		if (err) {
672 			if (errno != ENOENT) {
673 				p_err("%s", strerror(errno));
674 				goto err_close_fds;
675 			}
676 			return nb_fds;
677 		}
678 
679 		fd = bpf_prog_get_fd_by_id(id);
680 		if (fd < 0) {
681 			p_err("can't get prog by id (%u): %s",
682 			      id, strerror(errno));
683 			goto err_close_fds;
684 		}
685 
686 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
687 		if (err) {
688 			p_err("can't get prog info (%u): %s",
689 			      id, strerror(errno));
690 			goto err_close_fd;
691 		}
692 
693 		if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) ||
694 		    (!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) {
695 			close(fd);
696 			continue;
697 		}
698 
699 		if (nb_fds > 0) {
700 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
701 			if (!tmp) {
702 				p_err("failed to realloc");
703 				goto err_close_fd;
704 			}
705 			*fds = tmp;
706 		}
707 		(*fds)[nb_fds++] = fd;
708 	}
709 
710 err_close_fd:
711 	close(fd);
712 err_close_fds:
713 	while (--nb_fds >= 0)
714 		close((*fds)[nb_fds]);
715 	return -1;
716 }
717 
718 int prog_parse_fds(int *argc, char ***argv, int **fds)
719 {
720 	if (is_prefix(**argv, "id")) {
721 		unsigned int id;
722 		char *endptr;
723 
724 		NEXT_ARGP();
725 
726 		id = strtoul(**argv, &endptr, 0);
727 		if (*endptr) {
728 			p_err("can't parse %s as ID", **argv);
729 			return -1;
730 		}
731 		NEXT_ARGP();
732 
733 		(*fds)[0] = bpf_prog_get_fd_by_id(id);
734 		if ((*fds)[0] < 0) {
735 			p_err("get by id (%u): %s", id, strerror(errno));
736 			return -1;
737 		}
738 		return 1;
739 	} else if (is_prefix(**argv, "tag")) {
740 		unsigned char tag[BPF_TAG_SIZE];
741 
742 		NEXT_ARGP();
743 
744 		if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
745 			   tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
746 		    != BPF_TAG_SIZE) {
747 			p_err("can't parse tag");
748 			return -1;
749 		}
750 		NEXT_ARGP();
751 
752 		return prog_fd_by_nametag(tag, fds, true);
753 	} else if (is_prefix(**argv, "name")) {
754 		char *name;
755 
756 		NEXT_ARGP();
757 
758 		name = **argv;
759 		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
760 			p_err("can't parse name");
761 			return -1;
762 		}
763 		NEXT_ARGP();
764 
765 		return prog_fd_by_nametag(name, fds, false);
766 	} else if (is_prefix(**argv, "pinned")) {
767 		char *path;
768 
769 		NEXT_ARGP();
770 
771 		path = **argv;
772 		NEXT_ARGP();
773 
774 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
775 		if ((*fds)[0] < 0)
776 			return -1;
777 		return 1;
778 	}
779 
780 	p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
781 	return -1;
782 }
783 
784 int prog_parse_fd(int *argc, char ***argv)
785 {
786 	int *fds = NULL;
787 	int nb_fds, fd;
788 
789 	fds = malloc(sizeof(int));
790 	if (!fds) {
791 		p_err("mem alloc failed");
792 		return -1;
793 	}
794 	nb_fds = prog_parse_fds(argc, argv, &fds);
795 	if (nb_fds != 1) {
796 		if (nb_fds > 1) {
797 			p_err("several programs match this handle");
798 			while (nb_fds--)
799 				close(fds[nb_fds]);
800 		}
801 		fd = -1;
802 		goto exit_free;
803 	}
804 
805 	fd = fds[0];
806 exit_free:
807 	free(fds);
808 	return fd;
809 }
810 
811 static int map_fd_by_name(char *name, int **fds)
812 {
813 	unsigned int id = 0;
814 	int fd, nb_fds = 0;
815 	void *tmp;
816 	int err;
817 
818 	while (true) {
819 		struct bpf_map_info info = {};
820 		__u32 len = sizeof(info);
821 
822 		err = bpf_map_get_next_id(id, &id);
823 		if (err) {
824 			if (errno != ENOENT) {
825 				p_err("%s", strerror(errno));
826 				goto err_close_fds;
827 			}
828 			return nb_fds;
829 		}
830 
831 		fd = bpf_map_get_fd_by_id(id);
832 		if (fd < 0) {
833 			p_err("can't get map by id (%u): %s",
834 			      id, strerror(errno));
835 			goto err_close_fds;
836 		}
837 
838 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
839 		if (err) {
840 			p_err("can't get map info (%u): %s",
841 			      id, strerror(errno));
842 			goto err_close_fd;
843 		}
844 
845 		if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
846 			close(fd);
847 			continue;
848 		}
849 
850 		if (nb_fds > 0) {
851 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
852 			if (!tmp) {
853 				p_err("failed to realloc");
854 				goto err_close_fd;
855 			}
856 			*fds = tmp;
857 		}
858 		(*fds)[nb_fds++] = fd;
859 	}
860 
861 err_close_fd:
862 	close(fd);
863 err_close_fds:
864 	while (--nb_fds >= 0)
865 		close((*fds)[nb_fds]);
866 	return -1;
867 }
868 
869 int map_parse_fds(int *argc, char ***argv, int **fds)
870 {
871 	if (is_prefix(**argv, "id")) {
872 		unsigned int id;
873 		char *endptr;
874 
875 		NEXT_ARGP();
876 
877 		id = strtoul(**argv, &endptr, 0);
878 		if (*endptr) {
879 			p_err("can't parse %s as ID", **argv);
880 			return -1;
881 		}
882 		NEXT_ARGP();
883 
884 		(*fds)[0] = bpf_map_get_fd_by_id(id);
885 		if ((*fds)[0] < 0) {
886 			p_err("get map by id (%u): %s", id, strerror(errno));
887 			return -1;
888 		}
889 		return 1;
890 	} else if (is_prefix(**argv, "name")) {
891 		char *name;
892 
893 		NEXT_ARGP();
894 
895 		name = **argv;
896 		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
897 			p_err("can't parse name");
898 			return -1;
899 		}
900 		NEXT_ARGP();
901 
902 		return map_fd_by_name(name, fds);
903 	} else if (is_prefix(**argv, "pinned")) {
904 		char *path;
905 
906 		NEXT_ARGP();
907 
908 		path = **argv;
909 		NEXT_ARGP();
910 
911 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
912 		if ((*fds)[0] < 0)
913 			return -1;
914 		return 1;
915 	}
916 
917 	p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
918 	return -1;
919 }
920 
921 int map_parse_fd(int *argc, char ***argv)
922 {
923 	int *fds = NULL;
924 	int nb_fds, fd;
925 
926 	fds = malloc(sizeof(int));
927 	if (!fds) {
928 		p_err("mem alloc failed");
929 		return -1;
930 	}
931 	nb_fds = map_parse_fds(argc, argv, &fds);
932 	if (nb_fds != 1) {
933 		if (nb_fds > 1) {
934 			p_err("several maps match this handle");
935 			while (nb_fds--)
936 				close(fds[nb_fds]);
937 		}
938 		fd = -1;
939 		goto exit_free;
940 	}
941 
942 	fd = fds[0];
943 exit_free:
944 	free(fds);
945 	return fd;
946 }
947 
948 int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
949 {
950 	int err;
951 	int fd;
952 
953 	fd = map_parse_fd(argc, argv);
954 	if (fd < 0)
955 		return -1;
956 
957 	err = bpf_obj_get_info_by_fd(fd, info, info_len);
958 	if (err) {
959 		p_err("can't get map info: %s", strerror(errno));
960 		close(fd);
961 		return err;
962 	}
963 
964 	return fd;
965 }
966 
967 size_t hash_fn_for_key_as_id(const void *key, void *ctx)
968 {
969 	return (size_t)key;
970 }
971 
972 bool equal_fn_for_key_as_id(const void *k1, const void *k2, void *ctx)
973 {
974 	return k1 == k2;
975 }
976