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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_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
 72void 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
 90void 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
103static 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
113void set_max_rlimit(void)
114{
115	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
116
117	setrlimit(RLIMIT_MEMLOCK, &rinf);
118}
119
120static int
121mnt_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
152int 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
166int 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
188out_free:
189	free(pname);
190out_ret:
191	return fd;
192}
193
194int 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
217int 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	if (!file) {
226		p_err("mem alloc failed");
227		return -1;
228	}
229
230	strcpy(file, name);
231	dir = dirname(file);
232
233	if (is_bpffs(dir))
234		/* nothing to do if already mounted */
235		goto out_free;
236
237	if (block_mount) {
238		p_err("no BPF file system found, not mounting it due to --nomount option");
239		err = -1;
240		goto out_free;
241	}
242
243	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
244	if (err) {
245		err_str[ERR_MAX_LEN - 1] = '\0';
246		p_err("can't mount BPF file system to pin the object (%s): %s",
247		      name, err_str);
248	}
249
250out_free:
251	free(file);
252	return err;
253}
254
255int do_pin_fd(int fd, const char *name)
256{
257	int err;
258
259	err = mount_bpffs_for_pin(name);
260	if (err)
261		return err;
262
263	err = bpf_obj_pin(fd, name);
264	if (err)
265		p_err("can't pin the object (%s): %s", name, strerror(errno));
266
267	return err;
268}
269
270int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
271{
272	int err;
273	int fd;
274
275	fd = get_fd(&argc, &argv);
276	if (fd < 0)
277		return fd;
278
279	err = do_pin_fd(fd, *argv);
280
281	close(fd);
282	return err;
283}
284
285const char *get_fd_type_name(enum bpf_obj_type type)
286{
287	static const char * const names[] = {
288		[BPF_OBJ_UNKNOWN]	= "unknown",
289		[BPF_OBJ_PROG]		= "prog",
290		[BPF_OBJ_MAP]		= "map",
291	};
292
293	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
294		return names[BPF_OBJ_UNKNOWN];
295
296	return names[type];
297}
298
299int get_fd_type(int fd)
300{
301	char path[PATH_MAX];
302	char buf[512];
303	ssize_t n;
304
305	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
306
307	n = readlink(path, buf, sizeof(buf));
308	if (n < 0) {
309		p_err("can't read link type: %s", strerror(errno));
310		return -1;
311	}
312	if (n == sizeof(path)) {
313		p_err("can't read link type: path too long!");
314		return -1;
315	}
316
317	if (strstr(buf, "bpf-map"))
318		return BPF_OBJ_MAP;
319	else if (strstr(buf, "bpf-prog"))
320		return BPF_OBJ_PROG;
321	else if (strstr(buf, "bpf-link"))
322		return BPF_OBJ_LINK;
323
324	return BPF_OBJ_UNKNOWN;
325}
326
327char *get_fdinfo(int fd, const char *key)
328{
329	char path[PATH_MAX];
330	char *line = NULL;
331	size_t line_n = 0;
332	ssize_t n;
333	FILE *fdi;
334
335	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
336
337	fdi = fopen(path, "r");
338	if (!fdi)
339		return NULL;
340
341	while ((n = getline(&line, &line_n, fdi)) > 0) {
342		char *value;
343		int len;
344
345		if (!strstr(line, key))
346			continue;
347
348		fclose(fdi);
349
350		value = strchr(line, '\t');
351		if (!value || !value[1]) {
352			free(line);
353			return NULL;
354		}
355		value++;
356
357		len = strlen(value);
358		memmove(line, value, len);
359		line[len - 1] = '\0';
360
361		return line;
362	}
363
364	free(line);
365	fclose(fdi);
366	return NULL;
367}
368
369void print_data_json(uint8_t *data, size_t len)
370{
371	unsigned int i;
372
373	jsonw_start_array(json_wtr);
374	for (i = 0; i < len; i++)
375		jsonw_printf(json_wtr, "%d", data[i]);
376	jsonw_end_array(json_wtr);
377}
378
379void print_hex_data_json(uint8_t *data, size_t len)
380{
381	unsigned int i;
382
383	jsonw_start_array(json_wtr);
384	for (i = 0; i < len; i++)
385		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
386	jsonw_end_array(json_wtr);
387}
388
389/* extra params for nftw cb */
390static struct pinned_obj_table *build_fn_table;
391static enum bpf_obj_type build_fn_type;
392
393static int do_build_table_cb(const char *fpath, const struct stat *sb,
394			     int typeflag, struct FTW *ftwbuf)
395{
396	struct bpf_prog_info pinned_info;
397	__u32 len = sizeof(pinned_info);
398	struct pinned_obj *obj_node;
399	enum bpf_obj_type objtype;
400	int fd, err = 0;
401
402	if (typeflag != FTW_F)
403		goto out_ret;
404
405	fd = open_obj_pinned(fpath, true);
406	if (fd < 0)
407		goto out_ret;
408
409	objtype = get_fd_type(fd);
410	if (objtype != build_fn_type)
411		goto out_close;
412
413	memset(&pinned_info, 0, sizeof(pinned_info));
414	if (bpf_obj_get_info_by_fd(fd, &pinned_info, &len))
415		goto out_close;
416
417	obj_node = calloc(1, sizeof(*obj_node));
418	if (!obj_node) {
419		err = -1;
420		goto out_close;
421	}
422
423	obj_node->id = pinned_info.id;
424	obj_node->path = strdup(fpath);
425	if (!obj_node->path) {
426		err = -1;
427		free(obj_node);
428		goto out_close;
429	}
430
431	hash_add(build_fn_table->table, &obj_node->hash, obj_node->id);
432out_close:
433	close(fd);
434out_ret:
435	return err;
436}
437
438int build_pinned_obj_table(struct pinned_obj_table *tab,
439			   enum bpf_obj_type type)
440{
441	struct mntent *mntent = NULL;
442	FILE *mntfile = NULL;
443	int flags = FTW_PHYS;
444	int nopenfd = 16;
445	int err = 0;
446
447	mntfile = setmntent("/proc/mounts", "r");
448	if (!mntfile)
449		return -1;
450
451	build_fn_table = tab;
452	build_fn_type = type;
453
454	while ((mntent = getmntent(mntfile))) {
455		char *path = mntent->mnt_dir;
456
457		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
458			continue;
459		err = nftw(path, do_build_table_cb, nopenfd, flags);
460		if (err)
461			break;
462	}
463	fclose(mntfile);
464	return err;
465}
466
467void delete_pinned_obj_table(struct pinned_obj_table *tab)
468{
469	struct pinned_obj *obj;
470	struct hlist_node *tmp;
471	unsigned int bkt;
472
473	hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
474		hash_del(&obj->hash);
475		free(obj->path);
476		free(obj);
477	}
478}
479
480unsigned int get_page_size(void)
481{
482	static int result;
483
484	if (!result)
485		result = getpagesize();
486	return result;
487}
488
489unsigned int get_possible_cpus(void)
490{
491	int cpus = libbpf_num_possible_cpus();
492
493	if (cpus < 0) {
494		p_err("Can't get # of possible cpus: %s", strerror(-cpus));
495		exit(-1);
496	}
497	return cpus;
498}
499
500static char *
501ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
502{
503	struct stat st;
504	int err;
505
506	err = stat("/proc/self/ns/net", &st);
507	if (err) {
508		p_err("Can't stat /proc/self: %s", strerror(errno));
509		return NULL;
510	}
511
512	if (st.st_dev != ns_dev || st.st_ino != ns_ino)
513		return NULL;
514
515	return if_indextoname(ifindex, buf);
516}
517
518static int read_sysfs_hex_int(char *path)
519{
520	char vendor_id_buf[8];
521	int len;
522	int fd;
523
524	fd = open(path, O_RDONLY);
525	if (fd < 0) {
526		p_err("Can't open %s: %s", path, strerror(errno));
527		return -1;
528	}
529
530	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
531	close(fd);
532	if (len < 0) {
533		p_err("Can't read %s: %s", path, strerror(errno));
534		return -1;
535	}
536	if (len >= (int)sizeof(vendor_id_buf)) {
537		p_err("Value in %s too long", path);
538		return -1;
539	}
540
541	vendor_id_buf[len] = 0;
542
543	return strtol(vendor_id_buf, NULL, 0);
544}
545
546static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
547{
548	char full_path[64];
549
550	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
551		 devname, entry_name);
552
553	return read_sysfs_hex_int(full_path);
554}
555
556const char *
557ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
558		      const char **opt)
559{
560	char devname[IF_NAMESIZE];
561	int vendor_id;
562	int device_id;
563
564	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
565		p_err("Can't get net device name for ifindex %d: %s", ifindex,
566		      strerror(errno));
567		return NULL;
568	}
569
570	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
571	if (vendor_id < 0) {
572		p_err("Can't get device vendor id for %s", devname);
573		return NULL;
574	}
575
576	switch (vendor_id) {
577	case 0x19ee:
578		device_id = read_sysfs_netdev_hex_int(devname, "device");
579		if (device_id != 0x4000 &&
580		    device_id != 0x6000 &&
581		    device_id != 0x6003)
582			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
583		*opt = "ctx4";
584		return "NFP-6xxx";
585	default:
586		p_err("Can't get bfd arch name for device vendor id 0x%04x",
587		      vendor_id);
588		return NULL;
589	}
590}
591
592void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
593{
594	char name[IF_NAMESIZE];
595
596	if (!ifindex)
597		return;
598
599	printf("  offloaded_to ");
600	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
601		printf("%s", name);
602	else
603		printf("ifindex %u ns_dev %llu ns_ino %llu",
604		       ifindex, ns_dev, ns_inode);
605}
606
607void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
608{
609	char name[IF_NAMESIZE];
610
611	if (!ifindex)
612		return;
613
614	jsonw_name(json_wtr, "dev");
615	jsonw_start_object(json_wtr);
616	jsonw_uint_field(json_wtr, "ifindex", ifindex);
617	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
618	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
619	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
620		jsonw_string_field(json_wtr, "ifname", name);
621	jsonw_end_object(json_wtr);
622}
623
624int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
625{
626	char *endptr;
627
628	NEXT_ARGP();
629
630	if (*val) {
631		p_err("%s already specified", what);
632		return -1;
633	}
634
635	*val = strtoul(**argv, &endptr, 0);
636	if (*endptr) {
637		p_err("can't parse %s as %s", **argv, what);
638		return -1;
639	}
640	NEXT_ARGP();
641
642	return 0;
643}
644
645int __printf(2, 0)
646print_all_levels(__maybe_unused enum libbpf_print_level level,
647		 const char *format, va_list args)
648{
649	return vfprintf(stderr, format, args);
650}
651
652static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
653{
654	unsigned int id = 0;
655	int fd, nb_fds = 0;
656	void *tmp;
657	int err;
658
659	while (true) {
660		struct bpf_prog_info info = {};
661		__u32 len = sizeof(info);
662
663		err = bpf_prog_get_next_id(id, &id);
664		if (err) {
665			if (errno != ENOENT) {
666				p_err("%s", strerror(errno));
667				goto err_close_fds;
668			}
669			return nb_fds;
670		}
671
672		fd = bpf_prog_get_fd_by_id(id);
673		if (fd < 0) {
674			p_err("can't get prog by id (%u): %s",
675			      id, strerror(errno));
676			goto err_close_fds;
677		}
678
679		err = bpf_obj_get_info_by_fd(fd, &info, &len);
680		if (err) {
681			p_err("can't get prog info (%u): %s",
682			      id, strerror(errno));
683			goto err_close_fd;
684		}
685
686		if ((tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) ||
687		    (!tag && strncmp(nametag, info.name, BPF_OBJ_NAME_LEN))) {
688			close(fd);
689			continue;
690		}
691
692		if (nb_fds > 0) {
693			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
694			if (!tmp) {
695				p_err("failed to realloc");
696				goto err_close_fd;
697			}
698			*fds = tmp;
699		}
700		(*fds)[nb_fds++] = fd;
701	}
702
703err_close_fd:
704	close(fd);
705err_close_fds:
706	while (--nb_fds >= 0)
707		close((*fds)[nb_fds]);
708	return -1;
709}
710
711int prog_parse_fds(int *argc, char ***argv, int **fds)
712{
713	if (is_prefix(**argv, "id")) {
714		unsigned int id;
715		char *endptr;
716
717		NEXT_ARGP();
718
719		id = strtoul(**argv, &endptr, 0);
720		if (*endptr) {
721			p_err("can't parse %s as ID", **argv);
722			return -1;
723		}
724		NEXT_ARGP();
725
726		(*fds)[0] = bpf_prog_get_fd_by_id(id);
727		if ((*fds)[0] < 0) {
728			p_err("get by id (%u): %s", id, strerror(errno));
729			return -1;
730		}
731		return 1;
732	} else if (is_prefix(**argv, "tag")) {
733		unsigned char tag[BPF_TAG_SIZE];
734
735		NEXT_ARGP();
736
737		if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
738			   tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
739		    != BPF_TAG_SIZE) {
740			p_err("can't parse tag");
741			return -1;
742		}
743		NEXT_ARGP();
744
745		return prog_fd_by_nametag(tag, fds, true);
746	} else if (is_prefix(**argv, "name")) {
747		char *name;
748
749		NEXT_ARGP();
750
751		name = **argv;
752		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
753			p_err("can't parse name");
754			return -1;
755		}
756		NEXT_ARGP();
757
758		return prog_fd_by_nametag(name, fds, false);
759	} else if (is_prefix(**argv, "pinned")) {
760		char *path;
761
762		NEXT_ARGP();
763
764		path = **argv;
765		NEXT_ARGP();
766
767		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
768		if ((*fds)[0] < 0)
769			return -1;
770		return 1;
771	}
772
773	p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
774	return -1;
775}
776
777int prog_parse_fd(int *argc, char ***argv)
778{
779	int *fds = NULL;
780	int nb_fds, fd;
781
782	fds = malloc(sizeof(int));
783	if (!fds) {
784		p_err("mem alloc failed");
785		return -1;
786	}
787	nb_fds = prog_parse_fds(argc, argv, &fds);
788	if (nb_fds != 1) {
789		if (nb_fds > 1) {
790			p_err("several programs match this handle");
791			while (nb_fds--)
792				close(fds[nb_fds]);
793		}
794		fd = -1;
795		goto exit_free;
796	}
797
798	fd = fds[0];
799exit_free:
800	free(fds);
801	return fd;
802}
803
804static int map_fd_by_name(char *name, int **fds)
805{
806	unsigned int id = 0;
807	int fd, nb_fds = 0;
808	void *tmp;
809	int err;
810
811	while (true) {
812		struct bpf_map_info info = {};
813		__u32 len = sizeof(info);
814
815		err = bpf_map_get_next_id(id, &id);
816		if (err) {
817			if (errno != ENOENT) {
818				p_err("%s", strerror(errno));
819				goto err_close_fds;
820			}
821			return nb_fds;
822		}
823
824		fd = bpf_map_get_fd_by_id(id);
825		if (fd < 0) {
826			p_err("can't get map by id (%u): %s",
827			      id, strerror(errno));
828			goto err_close_fds;
829		}
830
831		err = bpf_obj_get_info_by_fd(fd, &info, &len);
832		if (err) {
833			p_err("can't get map info (%u): %s",
834			      id, strerror(errno));
835			goto err_close_fd;
836		}
837
838		if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
839			close(fd);
840			continue;
841		}
842
843		if (nb_fds > 0) {
844			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
845			if (!tmp) {
846				p_err("failed to realloc");
847				goto err_close_fd;
848			}
849			*fds = tmp;
850		}
851		(*fds)[nb_fds++] = fd;
852	}
853
854err_close_fd:
855	close(fd);
856err_close_fds:
857	while (--nb_fds >= 0)
858		close((*fds)[nb_fds]);
859	return -1;
860}
861
862int map_parse_fds(int *argc, char ***argv, int **fds)
863{
864	if (is_prefix(**argv, "id")) {
865		unsigned int id;
866		char *endptr;
867
868		NEXT_ARGP();
869
870		id = strtoul(**argv, &endptr, 0);
871		if (*endptr) {
872			p_err("can't parse %s as ID", **argv);
873			return -1;
874		}
875		NEXT_ARGP();
876
877		(*fds)[0] = bpf_map_get_fd_by_id(id);
878		if ((*fds)[0] < 0) {
879			p_err("get map by id (%u): %s", id, strerror(errno));
880			return -1;
881		}
882		return 1;
883	} else if (is_prefix(**argv, "name")) {
884		char *name;
885
886		NEXT_ARGP();
887
888		name = **argv;
889		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
890			p_err("can't parse name");
891			return -1;
892		}
893		NEXT_ARGP();
894
895		return map_fd_by_name(name, fds);
896	} else if (is_prefix(**argv, "pinned")) {
897		char *path;
898
899		NEXT_ARGP();
900
901		path = **argv;
902		NEXT_ARGP();
903
904		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
905		if ((*fds)[0] < 0)
906			return -1;
907		return 1;
908	}
909
910	p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
911	return -1;
912}
913
914int map_parse_fd(int *argc, char ***argv)
915{
916	int *fds = NULL;
917	int nb_fds, fd;
918
919	fds = malloc(sizeof(int));
920	if (!fds) {
921		p_err("mem alloc failed");
922		return -1;
923	}
924	nb_fds = map_parse_fds(argc, argv, &fds);
925	if (nb_fds != 1) {
926		if (nb_fds > 1) {
927			p_err("several maps match this handle");
928			while (nb_fds--)
929				close(fds[nb_fds]);
930		}
931		fd = -1;
932		goto exit_free;
933	}
934
935	fd = fds[0];
936exit_free:
937	free(fds);
938	return fd;
939}
940
941int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
942{
943	int err;
944	int fd;
945
946	fd = map_parse_fd(argc, argv);
947	if (fd < 0)
948		return -1;
949
950	err = bpf_obj_get_info_by_fd(fd, info, info_len);
951	if (err) {
952		p_err("can't get map info: %s", strerror(errno));
953		close(fd);
954		return err;
955	}
956
957	return fd;
958}