xref: /openbmc/linux/tools/bpf/bpftool/common.c (revision 8dda2eac)
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/libbpf.h> /* libbpf_num_possible_cpus */
26 
27 #include "main.h"
28 
29 #ifndef BPF_FS_MAGIC
30 #define BPF_FS_MAGIC		0xcafe4a11
31 #endif
32 
33 const char * const attach_type_name[__MAX_BPF_ATTACH_TYPE] = {
34 	[BPF_CGROUP_INET_INGRESS]	= "ingress",
35 	[BPF_CGROUP_INET_EGRESS]	= "egress",
36 	[BPF_CGROUP_INET_SOCK_CREATE]	= "sock_create",
37 	[BPF_CGROUP_INET_SOCK_RELEASE]	= "sock_release",
38 	[BPF_CGROUP_SOCK_OPS]		= "sock_ops",
39 	[BPF_CGROUP_DEVICE]		= "device",
40 	[BPF_CGROUP_INET4_BIND]		= "bind4",
41 	[BPF_CGROUP_INET6_BIND]		= "bind6",
42 	[BPF_CGROUP_INET4_CONNECT]	= "connect4",
43 	[BPF_CGROUP_INET6_CONNECT]	= "connect6",
44 	[BPF_CGROUP_INET4_POST_BIND]	= "post_bind4",
45 	[BPF_CGROUP_INET6_POST_BIND]	= "post_bind6",
46 	[BPF_CGROUP_INET4_GETPEERNAME]	= "getpeername4",
47 	[BPF_CGROUP_INET6_GETPEERNAME]	= "getpeername6",
48 	[BPF_CGROUP_INET4_GETSOCKNAME]	= "getsockname4",
49 	[BPF_CGROUP_INET6_GETSOCKNAME]	= "getsockname6",
50 	[BPF_CGROUP_UDP4_SENDMSG]	= "sendmsg4",
51 	[BPF_CGROUP_UDP6_SENDMSG]	= "sendmsg6",
52 	[BPF_CGROUP_SYSCTL]		= "sysctl",
53 	[BPF_CGROUP_UDP4_RECVMSG]	= "recvmsg4",
54 	[BPF_CGROUP_UDP6_RECVMSG]	= "recvmsg6",
55 	[BPF_CGROUP_GETSOCKOPT]		= "getsockopt",
56 	[BPF_CGROUP_SETSOCKOPT]		= "setsockopt",
57 
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 };
71 
72 void p_err(const char *fmt, ...)
73 {
74 	va_list ap;
75 
76 	va_start(ap, fmt);
77 	if (json_output) {
78 		jsonw_start_object(json_wtr);
79 		jsonw_name(json_wtr, "error");
80 		jsonw_vprintf_enquote(json_wtr, fmt, ap);
81 		jsonw_end_object(json_wtr);
82 	} else {
83 		fprintf(stderr, "Error: ");
84 		vfprintf(stderr, fmt, ap);
85 		fprintf(stderr, "\n");
86 	}
87 	va_end(ap);
88 }
89 
90 void p_info(const char *fmt, ...)
91 {
92 	va_list ap;
93 
94 	if (json_output)
95 		return;
96 
97 	va_start(ap, fmt);
98 	vfprintf(stderr, fmt, ap);
99 	fprintf(stderr, "\n");
100 	va_end(ap);
101 }
102 
103 static bool is_bpffs(char *path)
104 {
105 	struct statfs st_fs;
106 
107 	if (statfs(path, &st_fs) < 0)
108 		return false;
109 
110 	return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
111 }
112 
113 void set_max_rlimit(void)
114 {
115 	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
116 
117 	setrlimit(RLIMIT_MEMLOCK, &rinf);
118 }
119 
120 static int
121 mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
122 {
123 	bool bind_done = false;
124 
125 	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
126 		if (errno != EINVAL || bind_done) {
127 			snprintf(buff, bufflen,
128 				 "mount --make-private %s failed: %s",
129 				 target, strerror(errno));
130 			return -1;
131 		}
132 
133 		if (mount(target, target, "none", MS_BIND, NULL)) {
134 			snprintf(buff, bufflen,
135 				 "mount --bind %s %s failed: %s",
136 				 target, target, strerror(errno));
137 			return -1;
138 		}
139 
140 		bind_done = true;
141 	}
142 
143 	if (mount(type, target, type, 0, "mode=0700")) {
144 		snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
145 			 type, type, target, strerror(errno));
146 		return -1;
147 	}
148 
149 	return 0;
150 }
151 
152 int mount_tracefs(const char *target)
153 {
154 	char err_str[ERR_MAX_LEN];
155 	int err;
156 
157 	err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
158 	if (err) {
159 		err_str[ERR_MAX_LEN - 1] = '\0';
160 		p_err("can't mount tracefs: %s", err_str);
161 	}
162 
163 	return err;
164 }
165 
166 int open_obj_pinned(const char *path, bool quiet)
167 {
168 	char *pname;
169 	int fd = -1;
170 
171 	pname = strdup(path);
172 	if (!pname) {
173 		if (!quiet)
174 			p_err("mem alloc failed");
175 		goto out_ret;
176 	}
177 
178 	fd = bpf_obj_get(pname);
179 	if (fd < 0) {
180 		if (!quiet)
181 			p_err("bpf obj get (%s): %s", pname,
182 			      errno == EACCES && !is_bpffs(dirname(pname)) ?
183 			    "directory not in bpf file system (bpffs)" :
184 			    strerror(errno));
185 		goto out_free;
186 	}
187 
188 out_free:
189 	free(pname);
190 out_ret:
191 	return fd;
192 }
193 
194 int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)
195 {
196 	enum bpf_obj_type type;
197 	int fd;
198 
199 	fd = open_obj_pinned(path, false);
200 	if (fd < 0)
201 		return -1;
202 
203 	type = get_fd_type(fd);
204 	if (type < 0) {
205 		close(fd);
206 		return type;
207 	}
208 	if (type != exp_type) {
209 		p_err("incorrect object type: %s", get_fd_type_name(type));
210 		close(fd);
211 		return -1;
212 	}
213 
214 	return fd;
215 }
216 
217 int mount_bpffs_for_pin(const char *name)
218 {
219 	char err_str[ERR_MAX_LEN];
220 	char *file;
221 	char *dir;
222 	int err = 0;
223 
224 	file = malloc(strlen(name) + 1);
225 	strcpy(file, name);
226 	dir = dirname(file);
227 
228 	if (is_bpffs(dir))
229 		/* nothing to do if already mounted */
230 		goto out_free;
231 
232 	if (block_mount) {
233 		p_err("no BPF file system found, not mounting it due to --nomount option");
234 		err = -1;
235 		goto out_free;
236 	}
237 
238 	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
239 	if (err) {
240 		err_str[ERR_MAX_LEN - 1] = '\0';
241 		p_err("can't mount BPF file system to pin the object (%s): %s",
242 		      name, err_str);
243 	}
244 
245 out_free:
246 	free(file);
247 	return err;
248 }
249 
250 int do_pin_fd(int fd, const char *name)
251 {
252 	int err;
253 
254 	err = mount_bpffs_for_pin(name);
255 	if (err)
256 		return err;
257 
258 	err = bpf_obj_pin(fd, name);
259 	if (err)
260 		p_err("can't pin the object (%s): %s", name, strerror(errno));
261 
262 	return err;
263 }
264 
265 int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
266 {
267 	int err;
268 	int fd;
269 
270 	fd = get_fd(&argc, &argv);
271 	if (fd < 0)
272 		return fd;
273 
274 	err = do_pin_fd(fd, *argv);
275 
276 	close(fd);
277 	return err;
278 }
279 
280 const char *get_fd_type_name(enum bpf_obj_type type)
281 {
282 	static const char * const names[] = {
283 		[BPF_OBJ_UNKNOWN]	= "unknown",
284 		[BPF_OBJ_PROG]		= "prog",
285 		[BPF_OBJ_MAP]		= "map",
286 	};
287 
288 	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
289 		return names[BPF_OBJ_UNKNOWN];
290 
291 	return names[type];
292 }
293 
294 int get_fd_type(int fd)
295 {
296 	char path[PATH_MAX];
297 	char buf[512];
298 	ssize_t n;
299 
300 	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
301 
302 	n = readlink(path, buf, sizeof(buf));
303 	if (n < 0) {
304 		p_err("can't read link type: %s", strerror(errno));
305 		return -1;
306 	}
307 	if (n == sizeof(path)) {
308 		p_err("can't read link type: path too long!");
309 		return -1;
310 	}
311 
312 	if (strstr(buf, "bpf-map"))
313 		return BPF_OBJ_MAP;
314 	else if (strstr(buf, "bpf-prog"))
315 		return BPF_OBJ_PROG;
316 	else if (strstr(buf, "bpf-link"))
317 		return BPF_OBJ_LINK;
318 
319 	return BPF_OBJ_UNKNOWN;
320 }
321 
322 char *get_fdinfo(int fd, const char *key)
323 {
324 	char path[PATH_MAX];
325 	char *line = NULL;
326 	size_t line_n = 0;
327 	ssize_t n;
328 	FILE *fdi;
329 
330 	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
331 
332 	fdi = fopen(path, "r");
333 	if (!fdi)
334 		return NULL;
335 
336 	while ((n = getline(&line, &line_n, fdi)) > 0) {
337 		char *value;
338 		int len;
339 
340 		if (!strstr(line, key))
341 			continue;
342 
343 		fclose(fdi);
344 
345 		value = strchr(line, '\t');
346 		if (!value || !value[1]) {
347 			free(line);
348 			return NULL;
349 		}
350 		value++;
351 
352 		len = strlen(value);
353 		memmove(line, value, len);
354 		line[len - 1] = '\0';
355 
356 		return line;
357 	}
358 
359 	free(line);
360 	fclose(fdi);
361 	return NULL;
362 }
363 
364 void print_data_json(uint8_t *data, size_t len)
365 {
366 	unsigned int i;
367 
368 	jsonw_start_array(json_wtr);
369 	for (i = 0; i < len; i++)
370 		jsonw_printf(json_wtr, "%d", data[i]);
371 	jsonw_end_array(json_wtr);
372 }
373 
374 void print_hex_data_json(uint8_t *data, size_t len)
375 {
376 	unsigned int i;
377 
378 	jsonw_start_array(json_wtr);
379 	for (i = 0; i < len; i++)
380 		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
381 	jsonw_end_array(json_wtr);
382 }
383 
384 /* extra params for nftw cb */
385 static struct pinned_obj_table *build_fn_table;
386 static enum bpf_obj_type build_fn_type;
387 
388 static int do_build_table_cb(const char *fpath, const struct stat *sb,
389 			     int typeflag, struct FTW *ftwbuf)
390 {
391 	struct bpf_prog_info pinned_info;
392 	__u32 len = sizeof(pinned_info);
393 	struct pinned_obj *obj_node;
394 	enum bpf_obj_type objtype;
395 	int fd, err = 0;
396 
397 	if (typeflag != FTW_F)
398 		goto out_ret;
399 
400 	fd = open_obj_pinned(fpath, true);
401 	if (fd < 0)
402 		goto out_ret;
403 
404 	objtype = get_fd_type(fd);
405 	if (objtype != build_fn_type)
406 		goto out_close;
407 
408 	memset(&pinned_info, 0, sizeof(pinned_info));
409 	if (bpf_obj_get_info_by_fd(fd, &pinned_info, &len))
410 		goto out_close;
411 
412 	obj_node = calloc(1, sizeof(*obj_node));
413 	if (!obj_node) {
414 		err = -1;
415 		goto out_close;
416 	}
417 
418 	obj_node->id = pinned_info.id;
419 	obj_node->path = strdup(fpath);
420 	if (!obj_node->path) {
421 		err = -1;
422 		free(obj_node);
423 		goto out_close;
424 	}
425 
426 	hash_add(build_fn_table->table, &obj_node->hash, obj_node->id);
427 out_close:
428 	close(fd);
429 out_ret:
430 	return err;
431 }
432 
433 int build_pinned_obj_table(struct pinned_obj_table *tab,
434 			   enum bpf_obj_type type)
435 {
436 	struct mntent *mntent = NULL;
437 	FILE *mntfile = NULL;
438 	int flags = FTW_PHYS;
439 	int nopenfd = 16;
440 	int err = 0;
441 
442 	mntfile = setmntent("/proc/mounts", "r");
443 	if (!mntfile)
444 		return -1;
445 
446 	build_fn_table = tab;
447 	build_fn_type = type;
448 
449 	while ((mntent = getmntent(mntfile))) {
450 		char *path = mntent->mnt_dir;
451 
452 		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
453 			continue;
454 		err = nftw(path, do_build_table_cb, nopenfd, flags);
455 		if (err)
456 			break;
457 	}
458 	fclose(mntfile);
459 	return err;
460 }
461 
462 void delete_pinned_obj_table(struct pinned_obj_table *tab)
463 {
464 	struct pinned_obj *obj;
465 	struct hlist_node *tmp;
466 	unsigned int bkt;
467 
468 	hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
469 		hash_del(&obj->hash);
470 		free(obj->path);
471 		free(obj);
472 	}
473 }
474 
475 unsigned int get_page_size(void)
476 {
477 	static int result;
478 
479 	if (!result)
480 		result = getpagesize();
481 	return result;
482 }
483 
484 unsigned int get_possible_cpus(void)
485 {
486 	int cpus = libbpf_num_possible_cpus();
487 
488 	if (cpus < 0) {
489 		p_err("Can't get # of possible cpus: %s", strerror(-cpus));
490 		exit(-1);
491 	}
492 	return cpus;
493 }
494 
495 static char *
496 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
497 {
498 	struct stat st;
499 	int err;
500 
501 	err = stat("/proc/self/ns/net", &st);
502 	if (err) {
503 		p_err("Can't stat /proc/self: %s", strerror(errno));
504 		return NULL;
505 	}
506 
507 	if (st.st_dev != ns_dev || st.st_ino != ns_ino)
508 		return NULL;
509 
510 	return if_indextoname(ifindex, buf);
511 }
512 
513 static int read_sysfs_hex_int(char *path)
514 {
515 	char vendor_id_buf[8];
516 	int len;
517 	int fd;
518 
519 	fd = open(path, O_RDONLY);
520 	if (fd < 0) {
521 		p_err("Can't open %s: %s", path, strerror(errno));
522 		return -1;
523 	}
524 
525 	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
526 	close(fd);
527 	if (len < 0) {
528 		p_err("Can't read %s: %s", path, strerror(errno));
529 		return -1;
530 	}
531 	if (len >= (int)sizeof(vendor_id_buf)) {
532 		p_err("Value in %s too long", path);
533 		return -1;
534 	}
535 
536 	vendor_id_buf[len] = 0;
537 
538 	return strtol(vendor_id_buf, NULL, 0);
539 }
540 
541 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
542 {
543 	char full_path[64];
544 
545 	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
546 		 devname, entry_name);
547 
548 	return read_sysfs_hex_int(full_path);
549 }
550 
551 const char *
552 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
553 		      const char **opt)
554 {
555 	char devname[IF_NAMESIZE];
556 	int vendor_id;
557 	int device_id;
558 
559 	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
560 		p_err("Can't get net device name for ifindex %d: %s", ifindex,
561 		      strerror(errno));
562 		return NULL;
563 	}
564 
565 	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
566 	if (vendor_id < 0) {
567 		p_err("Can't get device vendor id for %s", devname);
568 		return NULL;
569 	}
570 
571 	switch (vendor_id) {
572 	case 0x19ee:
573 		device_id = read_sysfs_netdev_hex_int(devname, "device");
574 		if (device_id != 0x4000 &&
575 		    device_id != 0x6000 &&
576 		    device_id != 0x6003)
577 			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
578 		*opt = "ctx4";
579 		return "NFP-6xxx";
580 	default:
581 		p_err("Can't get bfd arch name for device vendor id 0x%04x",
582 		      vendor_id);
583 		return NULL;
584 	}
585 }
586 
587 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
588 {
589 	char name[IF_NAMESIZE];
590 
591 	if (!ifindex)
592 		return;
593 
594 	printf("  offloaded_to ");
595 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
596 		printf("%s", name);
597 	else
598 		printf("ifindex %u ns_dev %llu ns_ino %llu",
599 		       ifindex, ns_dev, ns_inode);
600 }
601 
602 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
603 {
604 	char name[IF_NAMESIZE];
605 
606 	if (!ifindex)
607 		return;
608 
609 	jsonw_name(json_wtr, "dev");
610 	jsonw_start_object(json_wtr);
611 	jsonw_uint_field(json_wtr, "ifindex", ifindex);
612 	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
613 	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
614 	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
615 		jsonw_string_field(json_wtr, "ifname", name);
616 	jsonw_end_object(json_wtr);
617 }
618 
619 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
620 {
621 	char *endptr;
622 
623 	NEXT_ARGP();
624 
625 	if (*val) {
626 		p_err("%s already specified", what);
627 		return -1;
628 	}
629 
630 	*val = strtoul(**argv, &endptr, 0);
631 	if (*endptr) {
632 		p_err("can't parse %s as %s", **argv, what);
633 		return -1;
634 	}
635 	NEXT_ARGP();
636 
637 	return 0;
638 }
639 
640 int __printf(2, 0)
641 print_all_levels(__maybe_unused enum libbpf_print_level level,
642 		 const char *format, va_list args)
643 {
644 	return vfprintf(stderr, format, args);
645 }
646 
647 static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
648 {
649 	unsigned int id = 0;
650 	int fd, nb_fds = 0;
651 	void *tmp;
652 	int err;
653 
654 	while (true) {
655 		struct bpf_prog_info info = {};
656 		__u32 len = sizeof(info);
657 
658 		err = bpf_prog_get_next_id(id, &id);
659 		if (err) {
660 			if (errno != ENOENT) {
661 				p_err("%s", strerror(errno));
662 				goto err_close_fds;
663 			}
664 			return nb_fds;
665 		}
666 
667 		fd = bpf_prog_get_fd_by_id(id);
668 		if (fd < 0) {
669 			p_err("can't get prog by id (%u): %s",
670 			      id, strerror(errno));
671 			goto err_close_fds;
672 		}
673 
674 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
675 		if (err) {
676 			p_err("can't get prog info (%u): %s",
677 			      id, strerror(errno));
678 			goto err_close_fd;
679 		}
680 
681 		if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) ||
682 		    (!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) {
683 			close(fd);
684 			continue;
685 		}
686 
687 		if (nb_fds > 0) {
688 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
689 			if (!tmp) {
690 				p_err("failed to realloc");
691 				goto err_close_fd;
692 			}
693 			*fds = tmp;
694 		}
695 		(*fds)[nb_fds++] = fd;
696 	}
697 
698 err_close_fd:
699 	close(fd);
700 err_close_fds:
701 	while (--nb_fds >= 0)
702 		close((*fds)[nb_fds]);
703 	return -1;
704 }
705 
706 int prog_parse_fds(int *argc, char ***argv, int **fds)
707 {
708 	if (is_prefix(**argv, "id")) {
709 		unsigned int id;
710 		char *endptr;
711 
712 		NEXT_ARGP();
713 
714 		id = strtoul(**argv, &endptr, 0);
715 		if (*endptr) {
716 			p_err("can't parse %s as ID", **argv);
717 			return -1;
718 		}
719 		NEXT_ARGP();
720 
721 		(*fds)[0] = bpf_prog_get_fd_by_id(id);
722 		if ((*fds)[0] < 0) {
723 			p_err("get by id (%u): %s", id, strerror(errno));
724 			return -1;
725 		}
726 		return 1;
727 	} else if (is_prefix(**argv, "tag")) {
728 		unsigned char tag[BPF_TAG_SIZE];
729 
730 		NEXT_ARGP();
731 
732 		if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
733 			   tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
734 		    != BPF_TAG_SIZE) {
735 			p_err("can't parse tag");
736 			return -1;
737 		}
738 		NEXT_ARGP();
739 
740 		return prog_fd_by_nametag(tag, fds, true);
741 	} else if (is_prefix(**argv, "name")) {
742 		char *name;
743 
744 		NEXT_ARGP();
745 
746 		name = **argv;
747 		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
748 			p_err("can't parse name");
749 			return -1;
750 		}
751 		NEXT_ARGP();
752 
753 		return prog_fd_by_nametag(name, fds, false);
754 	} else if (is_prefix(**argv, "pinned")) {
755 		char *path;
756 
757 		NEXT_ARGP();
758 
759 		path = **argv;
760 		NEXT_ARGP();
761 
762 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
763 		if ((*fds)[0] < 0)
764 			return -1;
765 		return 1;
766 	}
767 
768 	p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
769 	return -1;
770 }
771 
772 int prog_parse_fd(int *argc, char ***argv)
773 {
774 	int *fds = NULL;
775 	int nb_fds, fd;
776 
777 	fds = malloc(sizeof(int));
778 	if (!fds) {
779 		p_err("mem alloc failed");
780 		return -1;
781 	}
782 	nb_fds = prog_parse_fds(argc, argv, &fds);
783 	if (nb_fds != 1) {
784 		if (nb_fds > 1) {
785 			p_err("several programs match this handle");
786 			while (nb_fds--)
787 				close(fds[nb_fds]);
788 		}
789 		fd = -1;
790 		goto exit_free;
791 	}
792 
793 	fd = fds[0];
794 exit_free:
795 	free(fds);
796 	return fd;
797 }
798 
799 static int map_fd_by_name(char *name, int **fds)
800 {
801 	unsigned int id = 0;
802 	int fd, nb_fds = 0;
803 	void *tmp;
804 	int err;
805 
806 	while (true) {
807 		struct bpf_map_info info = {};
808 		__u32 len = sizeof(info);
809 
810 		err = bpf_map_get_next_id(id, &id);
811 		if (err) {
812 			if (errno != ENOENT) {
813 				p_err("%s", strerror(errno));
814 				goto err_close_fds;
815 			}
816 			return nb_fds;
817 		}
818 
819 		fd = bpf_map_get_fd_by_id(id);
820 		if (fd < 0) {
821 			p_err("can't get map by id (%u): %s",
822 			      id, strerror(errno));
823 			goto err_close_fds;
824 		}
825 
826 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
827 		if (err) {
828 			p_err("can't get map info (%u): %s",
829 			      id, strerror(errno));
830 			goto err_close_fd;
831 		}
832 
833 		if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
834 			close(fd);
835 			continue;
836 		}
837 
838 		if (nb_fds > 0) {
839 			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
840 			if (!tmp) {
841 				p_err("failed to realloc");
842 				goto err_close_fd;
843 			}
844 			*fds = tmp;
845 		}
846 		(*fds)[nb_fds++] = fd;
847 	}
848 
849 err_close_fd:
850 	close(fd);
851 err_close_fds:
852 	while (--nb_fds >= 0)
853 		close((*fds)[nb_fds]);
854 	return -1;
855 }
856 
857 int map_parse_fds(int *argc, char ***argv, int **fds)
858 {
859 	if (is_prefix(**argv, "id")) {
860 		unsigned int id;
861 		char *endptr;
862 
863 		NEXT_ARGP();
864 
865 		id = strtoul(**argv, &endptr, 0);
866 		if (*endptr) {
867 			p_err("can't parse %s as ID", **argv);
868 			return -1;
869 		}
870 		NEXT_ARGP();
871 
872 		(*fds)[0] = bpf_map_get_fd_by_id(id);
873 		if ((*fds)[0] < 0) {
874 			p_err("get map by id (%u): %s", id, strerror(errno));
875 			return -1;
876 		}
877 		return 1;
878 	} else if (is_prefix(**argv, "name")) {
879 		char *name;
880 
881 		NEXT_ARGP();
882 
883 		name = **argv;
884 		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
885 			p_err("can't parse name");
886 			return -1;
887 		}
888 		NEXT_ARGP();
889 
890 		return map_fd_by_name(name, fds);
891 	} else if (is_prefix(**argv, "pinned")) {
892 		char *path;
893 
894 		NEXT_ARGP();
895 
896 		path = **argv;
897 		NEXT_ARGP();
898 
899 		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
900 		if ((*fds)[0] < 0)
901 			return -1;
902 		return 1;
903 	}
904 
905 	p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
906 	return -1;
907 }
908 
909 int map_parse_fd(int *argc, char ***argv)
910 {
911 	int *fds = NULL;
912 	int nb_fds, fd;
913 
914 	fds = malloc(sizeof(int));
915 	if (!fds) {
916 		p_err("mem alloc failed");
917 		return -1;
918 	}
919 	nb_fds = map_parse_fds(argc, argv, &fds);
920 	if (nb_fds != 1) {
921 		if (nb_fds > 1) {
922 			p_err("several maps match this handle");
923 			while (nb_fds--)
924 				close(fds[nb_fds]);
925 		}
926 		fd = -1;
927 		goto exit_free;
928 	}
929 
930 	fd = fds[0];
931 exit_free:
932 	free(fds);
933 	return fd;
934 }
935 
936 int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
937 {
938 	int err;
939 	int fd;
940 
941 	fd = map_parse_fd(argc, argv);
942 	if (fd < 0)
943 		return -1;
944 
945 	err = bpf_obj_get_info_by_fd(fd, info, info_len);
946 	if (err) {
947 		p_err("can't get map info: %s", strerror(errno));
948 		close(fd);
949 		return err;
950 	}
951 
952 	return fd;
953 }
954