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