xref: /openbmc/linux/tools/bpf/bpftool/common.c (revision da1d9caf)
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/stat.h>
21 #include <sys/vfs.h>
22 
23 #include <bpf/bpf.h>
24 #include <bpf/hashmap.h>
25 #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
26 #include <bpf/btf.h>
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 	[BPF_SK_SKB_STREAM_PARSER]	= "sk_skb_stream_parser",
59 	[BPF_SK_SKB_STREAM_VERDICT]	= "sk_skb_stream_verdict",
60 	[BPF_SK_SKB_VERDICT]		= "sk_skb_verdict",
61 	[BPF_SK_MSG_VERDICT]		= "sk_msg_verdict",
62 	[BPF_LIRC_MODE2]		= "lirc_mode2",
63 	[BPF_FLOW_DISSECTOR]		= "flow_dissector",
64 	[BPF_TRACE_RAW_TP]		= "raw_tp",
65 	[BPF_TRACE_FENTRY]		= "fentry",
66 	[BPF_TRACE_FEXIT]		= "fexit",
67 	[BPF_MODIFY_RETURN]		= "mod_ret",
68 	[BPF_LSM_MAC]			= "lsm_mac",
69 	[BPF_SK_LOOKUP]			= "sk_lookup",
70 	[BPF_TRACE_ITER]		= "trace_iter",
71 	[BPF_XDP_DEVMAP]		= "xdp_devmap",
72 	[BPF_XDP_CPUMAP]		= "xdp_cpumap",
73 	[BPF_XDP]			= "xdp",
74 	[BPF_SK_REUSEPORT_SELECT]	= "sk_skb_reuseport_select",
75 	[BPF_SK_REUSEPORT_SELECT_OR_MIGRATE]	= "sk_skb_reuseport_select_or_migrate",
76 	[BPF_PERF_EVENT]		= "perf_event",
77 	[BPF_TRACE_KPROBE_MULTI]	= "trace_kprobe_multi",
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 static int
122 mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
123 {
124 	bool bind_done = false;
125 
126 	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
127 		if (errno != EINVAL || bind_done) {
128 			snprintf(buff, bufflen,
129 				 "mount --make-private %s failed: %s",
130 				 target, strerror(errno));
131 			return -1;
132 		}
133 
134 		if (mount(target, target, "none", MS_BIND, NULL)) {
135 			snprintf(buff, bufflen,
136 				 "mount --bind %s %s failed: %s",
137 				 target, target, strerror(errno));
138 			return -1;
139 		}
140 
141 		bind_done = true;
142 	}
143 
144 	if (mount(type, target, type, 0, "mode=0700")) {
145 		snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
146 			 type, type, target, strerror(errno));
147 		return -1;
148 	}
149 
150 	return 0;
151 }
152 
153 int mount_tracefs(const char *target)
154 {
155 	char err_str[ERR_MAX_LEN];
156 	int err;
157 
158 	err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
159 	if (err) {
160 		err_str[ERR_MAX_LEN - 1] = '\0';
161 		p_err("can't mount tracefs: %s", err_str);
162 	}
163 
164 	return err;
165 }
166 
167 int open_obj_pinned(const char *path, bool quiet)
168 {
169 	char *pname;
170 	int fd = -1;
171 
172 	pname = strdup(path);
173 	if (!pname) {
174 		if (!quiet)
175 			p_err("mem alloc failed");
176 		goto out_ret;
177 	}
178 
179 	fd = bpf_obj_get(pname);
180 	if (fd < 0) {
181 		if (!quiet)
182 			p_err("bpf obj get (%s): %s", pname,
183 			      errno == EACCES && !is_bpffs(dirname(pname)) ?
184 			    "directory not in bpf file system (bpffs)" :
185 			    strerror(errno));
186 		goto out_free;
187 	}
188 
189 out_free:
190 	free(pname);
191 out_ret:
192 	return fd;
193 }
194 
195 int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)
196 {
197 	enum bpf_obj_type type;
198 	int fd;
199 
200 	fd = open_obj_pinned(path, false);
201 	if (fd < 0)
202 		return -1;
203 
204 	type = get_fd_type(fd);
205 	if (type < 0) {
206 		close(fd);
207 		return type;
208 	}
209 	if (type != exp_type) {
210 		p_err("incorrect object type: %s", get_fd_type_name(type));
211 		close(fd);
212 		return -1;
213 	}
214 
215 	return fd;
216 }
217 
218 int mount_bpffs_for_pin(const char *name)
219 {
220 	char err_str[ERR_MAX_LEN];
221 	char *file;
222 	char *dir;
223 	int err = 0;
224 
225 	file = malloc(strlen(name) + 1);
226 	if (!file) {
227 		p_err("mem alloc failed");
228 		return -1;
229 	}
230 
231 	strcpy(file, name);
232 	dir = dirname(file);
233 
234 	if (is_bpffs(dir))
235 		/* nothing to do if already mounted */
236 		goto out_free;
237 
238 	if (block_mount) {
239 		p_err("no BPF file system found, not mounting it due to --nomount option");
240 		err = -1;
241 		goto out_free;
242 	}
243 
244 	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
245 	if (err) {
246 		err_str[ERR_MAX_LEN - 1] = '\0';
247 		p_err("can't mount BPF file system to pin the object (%s): %s",
248 		      name, err_str);
249 	}
250 
251 out_free:
252 	free(file);
253 	return err;
254 }
255 
256 int do_pin_fd(int fd, const char *name)
257 {
258 	int err;
259 
260 	err = mount_bpffs_for_pin(name);
261 	if (err)
262 		return err;
263 
264 	err = bpf_obj_pin(fd, name);
265 	if (err)
266 		p_err("can't pin the object (%s): %s", name, strerror(errno));
267 
268 	return err;
269 }
270 
271 int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
272 {
273 	int err;
274 	int fd;
275 
276 	fd = get_fd(&argc, &argv);
277 	if (fd < 0)
278 		return fd;
279 
280 	err = do_pin_fd(fd, *argv);
281 
282 	close(fd);
283 	return err;
284 }
285 
286 const char *get_fd_type_name(enum bpf_obj_type type)
287 {
288 	static const char * const names[] = {
289 		[BPF_OBJ_UNKNOWN]	= "unknown",
290 		[BPF_OBJ_PROG]		= "prog",
291 		[BPF_OBJ_MAP]		= "map",
292 	};
293 
294 	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
295 		return names[BPF_OBJ_UNKNOWN];
296 
297 	return names[type];
298 }
299 
300 void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd,
301 			char *name_buff, size_t buff_len)
302 {
303 	const char *prog_name = prog_info->name;
304 	const struct btf_type *func_type;
305 	const struct bpf_func_info finfo = {};
306 	struct bpf_prog_info info = {};
307 	__u32 info_len = sizeof(info);
308 	struct btf *prog_btf = NULL;
309 
310 	if (buff_len <= BPF_OBJ_NAME_LEN ||
311 	    strlen(prog_info->name) < BPF_OBJ_NAME_LEN - 1)
312 		goto copy_name;
313 
314 	if (!prog_info->btf_id || prog_info->nr_func_info == 0)
315 		goto copy_name;
316 
317 	info.nr_func_info = 1;
318 	info.func_info_rec_size = prog_info->func_info_rec_size;
319 	if (info.func_info_rec_size > sizeof(finfo))
320 		info.func_info_rec_size = sizeof(finfo);
321 	info.func_info = ptr_to_u64(&finfo);
322 
323 	if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len))
324 		goto copy_name;
325 
326 	prog_btf = btf__load_from_kernel_by_id(info.btf_id);
327 	if (!prog_btf)
328 		goto copy_name;
329 
330 	func_type = btf__type_by_id(prog_btf, finfo.type_id);
331 	if (!func_type || !btf_is_func(func_type))
332 		goto copy_name;
333 
334 	prog_name = btf__name_by_offset(prog_btf, func_type->name_off);
335 
336 copy_name:
337 	snprintf(name_buff, buff_len, "%s", prog_name);
338 
339 	if (prog_btf)
340 		btf__free(prog_btf);
341 }
342 
343 int get_fd_type(int fd)
344 {
345 	char path[PATH_MAX];
346 	char buf[512];
347 	ssize_t n;
348 
349 	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
350 
351 	n = readlink(path, buf, sizeof(buf));
352 	if (n < 0) {
353 		p_err("can't read link type: %s", strerror(errno));
354 		return -1;
355 	}
356 	if (n == sizeof(path)) {
357 		p_err("can't read link type: path too long!");
358 		return -1;
359 	}
360 
361 	if (strstr(buf, "bpf-map"))
362 		return BPF_OBJ_MAP;
363 	else if (strstr(buf, "bpf-prog"))
364 		return BPF_OBJ_PROG;
365 	else if (strstr(buf, "bpf-link"))
366 		return BPF_OBJ_LINK;
367 
368 	return BPF_OBJ_UNKNOWN;
369 }
370 
371 char *get_fdinfo(int fd, const char *key)
372 {
373 	char path[PATH_MAX];
374 	char *line = NULL;
375 	size_t line_n = 0;
376 	ssize_t n;
377 	FILE *fdi;
378 
379 	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
380 
381 	fdi = fopen(path, "r");
382 	if (!fdi)
383 		return NULL;
384 
385 	while ((n = getline(&line, &line_n, fdi)) > 0) {
386 		char *value;
387 		int len;
388 
389 		if (!strstr(line, key))
390 			continue;
391 
392 		fclose(fdi);
393 
394 		value = strchr(line, '\t');
395 		if (!value || !value[1]) {
396 			free(line);
397 			return NULL;
398 		}
399 		value++;
400 
401 		len = strlen(value);
402 		memmove(line, value, len);
403 		line[len - 1] = '\0';
404 
405 		return line;
406 	}
407 
408 	free(line);
409 	fclose(fdi);
410 	return NULL;
411 }
412 
413 void print_data_json(uint8_t *data, size_t len)
414 {
415 	unsigned int i;
416 
417 	jsonw_start_array(json_wtr);
418 	for (i = 0; i < len; i++)
419 		jsonw_printf(json_wtr, "%d", data[i]);
420 	jsonw_end_array(json_wtr);
421 }
422 
423 void print_hex_data_json(uint8_t *data, size_t len)
424 {
425 	unsigned int i;
426 
427 	jsonw_start_array(json_wtr);
428 	for (i = 0; i < len; i++)
429 		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
430 	jsonw_end_array(json_wtr);
431 }
432 
433 /* extra params for nftw cb */
434 static struct hashmap *build_fn_table;
435 static enum bpf_obj_type build_fn_type;
436 
437 static int do_build_table_cb(const char *fpath, const struct stat *sb,
438 			     int typeflag, struct FTW *ftwbuf)
439 {
440 	struct bpf_prog_info pinned_info;
441 	__u32 len = sizeof(pinned_info);
442 	enum bpf_obj_type objtype;
443 	int fd, err = 0;
444 	char *path;
445 
446 	if (typeflag != FTW_F)
447 		goto out_ret;
448 
449 	fd = open_obj_pinned(fpath, true);
450 	if (fd < 0)
451 		goto out_ret;
452 
453 	objtype = get_fd_type(fd);
454 	if (objtype != build_fn_type)
455 		goto out_close;
456 
457 	memset(&pinned_info, 0, sizeof(pinned_info));
458 	if (bpf_obj_get_info_by_fd(fd, &pinned_info, &len))
459 		goto out_close;
460 
461 	path = strdup(fpath);
462 	if (!path) {
463 		err = -1;
464 		goto out_close;
465 	}
466 
467 	err = hashmap__append(build_fn_table, u32_as_hash_field(pinned_info.id), path);
468 	if (err) {
469 		p_err("failed to append entry to hashmap for ID %u, path '%s': %s",
470 		      pinned_info.id, path, strerror(errno));
471 		goto out_close;
472 	}
473 
474 out_close:
475 	close(fd);
476 out_ret:
477 	return err;
478 }
479 
480 int build_pinned_obj_table(struct hashmap *tab,
481 			   enum bpf_obj_type type)
482 {
483 	struct mntent *mntent = NULL;
484 	FILE *mntfile = NULL;
485 	int flags = FTW_PHYS;
486 	int nopenfd = 16;
487 	int err = 0;
488 
489 	mntfile = setmntent("/proc/mounts", "r");
490 	if (!mntfile)
491 		return -1;
492 
493 	build_fn_table = tab;
494 	build_fn_type = type;
495 
496 	while ((mntent = getmntent(mntfile))) {
497 		char *path = mntent->mnt_dir;
498 
499 		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
500 			continue;
501 		err = nftw(path, do_build_table_cb, nopenfd, flags);
502 		if (err)
503 			break;
504 	}
505 	fclose(mntfile);
506 	return err;
507 }
508 
509 void delete_pinned_obj_table(struct hashmap *map)
510 {
511 	struct hashmap_entry *entry;
512 	size_t bkt;
513 
514 	if (!map)
515 		return;
516 
517 	hashmap__for_each_entry(map, entry, bkt)
518 		free(entry->value);
519 
520 	hashmap__free(map);
521 }
522 
523 unsigned int get_page_size(void)
524 {
525 	static int result;
526 
527 	if (!result)
528 		result = getpagesize();
529 	return result;
530 }
531 
532 unsigned int get_possible_cpus(void)
533 {
534 	int cpus = libbpf_num_possible_cpus();
535 
536 	if (cpus < 0) {
537 		p_err("Can't get # of possible cpus: %s", strerror(-cpus));
538 		exit(-1);
539 	}
540 	return cpus;
541 }
542 
543 static char *
544 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
545 {
546 	struct stat st;
547 	int err;
548 
549 	err = stat("/proc/self/ns/net", &st);
550 	if (err) {
551 		p_err("Can't stat /proc/self: %s", strerror(errno));
552 		return NULL;
553 	}
554 
555 	if (st.st_dev != ns_dev || st.st_ino != ns_ino)
556 		return NULL;
557 
558 	return if_indextoname(ifindex, buf);
559 }
560 
561 static int read_sysfs_hex_int(char *path)
562 {
563 	char vendor_id_buf[8];
564 	int len;
565 	int fd;
566 
567 	fd = open(path, O_RDONLY);
568 	if (fd < 0) {
569 		p_err("Can't open %s: %s", path, strerror(errno));
570 		return -1;
571 	}
572 
573 	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
574 	close(fd);
575 	if (len < 0) {
576 		p_err("Can't read %s: %s", path, strerror(errno));
577 		return -1;
578 	}
579 	if (len >= (int)sizeof(vendor_id_buf)) {
580 		p_err("Value in %s too long", path);
581 		return -1;
582 	}
583 
584 	vendor_id_buf[len] = 0;
585 
586 	return strtol(vendor_id_buf, NULL, 0);
587 }
588 
589 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
590 {
591 	char full_path[64];
592 
593 	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
594 		 devname, entry_name);
595 
596 	return read_sysfs_hex_int(full_path);
597 }
598 
599 const char *
600 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
601 		      const char **opt)
602 {
603 	char devname[IF_NAMESIZE];
604 	int vendor_id;
605 	int device_id;
606 
607 	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
608 		p_err("Can't get net device name for ifindex %d: %s", ifindex,
609 		      strerror(errno));
610 		return NULL;
611 	}
612 
613 	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
614 	if (vendor_id < 0) {
615 		p_err("Can't get device vendor id for %s", devname);
616 		return NULL;
617 	}
618 
619 	switch (vendor_id) {
620 	case 0x19ee:
621 		device_id = read_sysfs_netdev_hex_int(devname, "device");
622 		if (device_id != 0x4000 &&
623 		    device_id != 0x6000 &&
624 		    device_id != 0x6003)
625 			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
626 		*opt = "ctx4";
627 		return "NFP-6xxx";
628 	default:
629 		p_err("Can't get bfd arch name for device vendor id 0x%04x",
630 		      vendor_id);
631 		return NULL;
632 	}
633 }
634 
635 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
636 {
637 	char name[IF_NAMESIZE];
638 
639 	if (!ifindex)
640 		return;
641 
642 	printf("  offloaded_to ");
643 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
644 		printf("%s", name);
645 	else
646 		printf("ifindex %u ns_dev %llu ns_ino %llu",
647 		       ifindex, ns_dev, ns_inode);
648 }
649 
650 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
651 {
652 	char name[IF_NAMESIZE];
653 
654 	if (!ifindex)
655 		return;
656 
657 	jsonw_name(json_wtr, "dev");
658 	jsonw_start_object(json_wtr);
659 	jsonw_uint_field(json_wtr, "ifindex", ifindex);
660 	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
661 	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
662 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
663 		jsonw_string_field(json_wtr, "ifname", name);
664 	jsonw_end_object(json_wtr);
665 }
666 
667 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
668 {
669 	char *endptr;
670 
671 	NEXT_ARGP();
672 
673 	if (*val) {
674 		p_err("%s already specified", what);
675 		return -1;
676 	}
677 
678 	*val = strtoul(**argv, &endptr, 0);
679 	if (*endptr) {
680 		p_err("can't parse %s as %s", **argv, what);
681 		return -1;
682 	}
683 	NEXT_ARGP();
684 
685 	return 0;
686 }
687 
688 int __printf(2, 0)
689 print_all_levels(__maybe_unused enum libbpf_print_level level,
690 		 const char *format, va_list args)
691 {
692 	return vfprintf(stderr, format, args);
693 }
694 
695 static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
696 {
697 	unsigned int id = 0;
698 	int fd, nb_fds = 0;
699 	void *tmp;
700 	int err;
701 
702 	while (true) {
703 		struct bpf_prog_info info = {};
704 		__u32 len = sizeof(info);
705 
706 		err = bpf_prog_get_next_id(id, &id);
707 		if (err) {
708 			if (errno != ENOENT) {
709 				p_err("%s", strerror(errno));
710 				goto err_close_fds;
711 			}
712 			return nb_fds;
713 		}
714 
715 		fd = bpf_prog_get_fd_by_id(id);
716 		if (fd < 0) {
717 			p_err("can't get prog by id (%u): %s",
718 			      id, strerror(errno));
719 			goto err_close_fds;
720 		}
721 
722 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
723 		if (err) {
724 			p_err("can't get prog info (%u): %s",
725 			      id, strerror(errno));
726 			goto err_close_fd;
727 		}
728 
729 		if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) ||
730 		    (!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) {
731 			close(fd);
732 			continue;
733 		}
734 
735 		if (nb_fds > 0) {
736 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
737 			if (!tmp) {
738 				p_err("failed to realloc");
739 				goto err_close_fd;
740 			}
741 			*fds = tmp;
742 		}
743 		(*fds)[nb_fds++] = fd;
744 	}
745 
746 err_close_fd:
747 	close(fd);
748 err_close_fds:
749 	while (--nb_fds >= 0)
750 		close((*fds)[nb_fds]);
751 	return -1;
752 }
753 
754 int prog_parse_fds(int *argc, char ***argv, int **fds)
755 {
756 	if (is_prefix(**argv, "id")) {
757 		unsigned int id;
758 		char *endptr;
759 
760 		NEXT_ARGP();
761 
762 		id = strtoul(**argv, &endptr, 0);
763 		if (*endptr) {
764 			p_err("can't parse %s as ID", **argv);
765 			return -1;
766 		}
767 		NEXT_ARGP();
768 
769 		(*fds)[0] = bpf_prog_get_fd_by_id(id);
770 		if ((*fds)[0] < 0) {
771 			p_err("get by id (%u): %s", id, strerror(errno));
772 			return -1;
773 		}
774 		return 1;
775 	} else if (is_prefix(**argv, "tag")) {
776 		unsigned char tag[BPF_TAG_SIZE];
777 
778 		NEXT_ARGP();
779 
780 		if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
781 			   tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
782 		    != BPF_TAG_SIZE) {
783 			p_err("can't parse tag");
784 			return -1;
785 		}
786 		NEXT_ARGP();
787 
788 		return prog_fd_by_nametag(tag, fds, true);
789 	} else if (is_prefix(**argv, "name")) {
790 		char *name;
791 
792 		NEXT_ARGP();
793 
794 		name = **argv;
795 		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
796 			p_err("can't parse name");
797 			return -1;
798 		}
799 		NEXT_ARGP();
800 
801 		return prog_fd_by_nametag(name, fds, false);
802 	} else if (is_prefix(**argv, "pinned")) {
803 		char *path;
804 
805 		NEXT_ARGP();
806 
807 		path = **argv;
808 		NEXT_ARGP();
809 
810 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
811 		if ((*fds)[0] < 0)
812 			return -1;
813 		return 1;
814 	}
815 
816 	p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
817 	return -1;
818 }
819 
820 int prog_parse_fd(int *argc, char ***argv)
821 {
822 	int *fds = NULL;
823 	int nb_fds, fd;
824 
825 	fds = malloc(sizeof(int));
826 	if (!fds) {
827 		p_err("mem alloc failed");
828 		return -1;
829 	}
830 	nb_fds = prog_parse_fds(argc, argv, &fds);
831 	if (nb_fds != 1) {
832 		if (nb_fds > 1) {
833 			p_err("several programs match this handle");
834 			while (nb_fds--)
835 				close(fds[nb_fds]);
836 		}
837 		fd = -1;
838 		goto exit_free;
839 	}
840 
841 	fd = fds[0];
842 exit_free:
843 	free(fds);
844 	return fd;
845 }
846 
847 static int map_fd_by_name(char *name, int **fds)
848 {
849 	unsigned int id = 0;
850 	int fd, nb_fds = 0;
851 	void *tmp;
852 	int err;
853 
854 	while (true) {
855 		struct bpf_map_info info = {};
856 		__u32 len = sizeof(info);
857 
858 		err = bpf_map_get_next_id(id, &id);
859 		if (err) {
860 			if (errno != ENOENT) {
861 				p_err("%s", strerror(errno));
862 				goto err_close_fds;
863 			}
864 			return nb_fds;
865 		}
866 
867 		fd = bpf_map_get_fd_by_id(id);
868 		if (fd < 0) {
869 			p_err("can't get map by id (%u): %s",
870 			      id, strerror(errno));
871 			goto err_close_fds;
872 		}
873 
874 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
875 		if (err) {
876 			p_err("can't get map info (%u): %s",
877 			      id, strerror(errno));
878 			goto err_close_fd;
879 		}
880 
881 		if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
882 			close(fd);
883 			continue;
884 		}
885 
886 		if (nb_fds > 0) {
887 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
888 			if (!tmp) {
889 				p_err("failed to realloc");
890 				goto err_close_fd;
891 			}
892 			*fds = tmp;
893 		}
894 		(*fds)[nb_fds++] = fd;
895 	}
896 
897 err_close_fd:
898 	close(fd);
899 err_close_fds:
900 	while (--nb_fds >= 0)
901 		close((*fds)[nb_fds]);
902 	return -1;
903 }
904 
905 int map_parse_fds(int *argc, char ***argv, int **fds)
906 {
907 	if (is_prefix(**argv, "id")) {
908 		unsigned int id;
909 		char *endptr;
910 
911 		NEXT_ARGP();
912 
913 		id = strtoul(**argv, &endptr, 0);
914 		if (*endptr) {
915 			p_err("can't parse %s as ID", **argv);
916 			return -1;
917 		}
918 		NEXT_ARGP();
919 
920 		(*fds)[0] = bpf_map_get_fd_by_id(id);
921 		if ((*fds)[0] < 0) {
922 			p_err("get map by id (%u): %s", id, strerror(errno));
923 			return -1;
924 		}
925 		return 1;
926 	} else if (is_prefix(**argv, "name")) {
927 		char *name;
928 
929 		NEXT_ARGP();
930 
931 		name = **argv;
932 		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
933 			p_err("can't parse name");
934 			return -1;
935 		}
936 		NEXT_ARGP();
937 
938 		return map_fd_by_name(name, fds);
939 	} else if (is_prefix(**argv, "pinned")) {
940 		char *path;
941 
942 		NEXT_ARGP();
943 
944 		path = **argv;
945 		NEXT_ARGP();
946 
947 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
948 		if ((*fds)[0] < 0)
949 			return -1;
950 		return 1;
951 	}
952 
953 	p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
954 	return -1;
955 }
956 
957 int map_parse_fd(int *argc, char ***argv)
958 {
959 	int *fds = NULL;
960 	int nb_fds, fd;
961 
962 	fds = malloc(sizeof(int));
963 	if (!fds) {
964 		p_err("mem alloc failed");
965 		return -1;
966 	}
967 	nb_fds = map_parse_fds(argc, argv, &fds);
968 	if (nb_fds != 1) {
969 		if (nb_fds > 1) {
970 			p_err("several maps match this handle");
971 			while (nb_fds--)
972 				close(fds[nb_fds]);
973 		}
974 		fd = -1;
975 		goto exit_free;
976 	}
977 
978 	fd = fds[0];
979 exit_free:
980 	free(fds);
981 	return fd;
982 }
983 
984 int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
985 {
986 	int err;
987 	int fd;
988 
989 	fd = map_parse_fd(argc, argv);
990 	if (fd < 0)
991 		return -1;
992 
993 	err = bpf_obj_get_info_by_fd(fd, info, info_len);
994 	if (err) {
995 		p_err("can't get map info: %s", strerror(errno));
996 		close(fd);
997 		return err;
998 	}
999 
1000 	return fd;
1001 }
1002 
1003 size_t hash_fn_for_key_as_id(const void *key, void *ctx)
1004 {
1005 	return (size_t)key;
1006 }
1007 
1008 bool equal_fn_for_key_as_id(const void *k1, const void *k2, void *ctx)
1009 {
1010 	return k1 == k2;
1011 }
1012