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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#ifndef _GNU_SOURCE5#define _GNU_SOURCE6#endif7#include <ctype.h>8#include <errno.h>9#include <fcntl.h>10#include <ftw.h>11#include <libgen.h>12#include <mntent.h>13#include <stdbool.h>14#include <stdio.h>15#include <stdlib.h>16#include <string.h>17#include <unistd.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 <linux/filter.h>25#include <linux/limits.h>26#include <linux/magic.h>27#include <linux/unistd.h>28 29#include <bpf/bpf.h>30#include <bpf/hashmap.h>31#include <bpf/libbpf.h> /* libbpf_num_possible_cpus */32#include <bpf/btf.h>33 34#include "main.h"35 36#ifndef BPF_FS_MAGIC37#define BPF_FS_MAGIC		0xcafe4a1138#endif39 40void p_err(const char *fmt, ...)41{42	va_list ap;43 44	va_start(ap, fmt);45	if (json_output) {46		jsonw_start_object(json_wtr);47		jsonw_name(json_wtr, "error");48		jsonw_vprintf_enquote(json_wtr, fmt, ap);49		jsonw_end_object(json_wtr);50	} else {51		fprintf(stderr, "Error: ");52		vfprintf(stderr, fmt, ap);53		fprintf(stderr, "\n");54	}55	va_end(ap);56}57 58void p_info(const char *fmt, ...)59{60	va_list ap;61 62	if (json_output)63		return;64 65	va_start(ap, fmt);66	vfprintf(stderr, fmt, ap);67	fprintf(stderr, "\n");68	va_end(ap);69}70 71static bool is_bpffs(const char *path)72{73	struct statfs st_fs;74 75	if (statfs(path, &st_fs) < 0)76		return false;77 78	return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;79}80 81/* Probe whether kernel switched from memlock-based (RLIMIT_MEMLOCK) to82 * memcg-based memory accounting for BPF maps and programs. This was done in83 * commit 97306be45fbe ("Merge branch 'switch to memcg-based memory84 * accounting'"), in Linux 5.11.85 *86 * Libbpf also offers to probe for memcg-based accounting vs rlimit, but does87 * so by checking for the availability of a given BPF helper and this has88 * failed on some kernels with backports in the past, see commit 6b4384ff108889 * ("Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"").90 * Instead, we can probe by lowering the process-based rlimit to 0, trying to91 * load a BPF object, and resetting the rlimit. If the load succeeds then92 * memcg-based accounting is supported.93 *94 * This would be too dangerous to do in the library, because multithreaded95 * applications might attempt to load items while the rlimit is at 0. Given96 * that bpftool is single-threaded, this is fine to do here.97 */98static bool known_to_need_rlimit(void)99{100	struct rlimit rlim_init, rlim_cur_zero = {};101	struct bpf_insn insns[] = {102		BPF_MOV64_IMM(BPF_REG_0, 0),103		BPF_EXIT_INSN(),104	};105	size_t insn_cnt = ARRAY_SIZE(insns);106	union bpf_attr attr;107	int prog_fd, err;108 109	memset(&attr, 0, sizeof(attr));110	attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;111	attr.insns = ptr_to_u64(insns);112	attr.insn_cnt = insn_cnt;113	attr.license = ptr_to_u64("GPL");114 115	if (getrlimit(RLIMIT_MEMLOCK, &rlim_init))116		return false;117 118	/* Drop the soft limit to zero. We maintain the hard limit to its119	 * current value, because lowering it would be a permanent operation120	 * for unprivileged users.121	 */122	rlim_cur_zero.rlim_max = rlim_init.rlim_max;123	if (setrlimit(RLIMIT_MEMLOCK, &rlim_cur_zero))124		return false;125 126	/* Do not use bpf_prog_load() from libbpf here, because it calls127	 * bump_rlimit_memlock(), interfering with the current probe.128	 */129	prog_fd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));130	err = errno;131 132	/* reset soft rlimit to its initial value */133	setrlimit(RLIMIT_MEMLOCK, &rlim_init);134 135	if (prog_fd < 0)136		return err == EPERM;137 138	close(prog_fd);139	return false;140}141 142void set_max_rlimit(void)143{144	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };145 146	if (known_to_need_rlimit())147		setrlimit(RLIMIT_MEMLOCK, &rinf);148}149 150static int151mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)152{153	bool bind_done = false;154 155	while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {156		if (errno != EINVAL || bind_done) {157			snprintf(buff, bufflen,158				 "mount --make-private %s failed: %s",159				 target, strerror(errno));160			return -1;161		}162 163		if (mount(target, target, "none", MS_BIND, NULL)) {164			snprintf(buff, bufflen,165				 "mount --bind %s %s failed: %s",166				 target, target, strerror(errno));167			return -1;168		}169 170		bind_done = true;171	}172 173	if (mount(type, target, type, 0, "mode=0700")) {174		snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",175			 type, type, target, strerror(errno));176		return -1;177	}178 179	return 0;180}181 182int mount_tracefs(const char *target)183{184	char err_str[ERR_MAX_LEN];185	int err;186 187	err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);188	if (err) {189		err_str[ERR_MAX_LEN - 1] = '\0';190		p_err("can't mount tracefs: %s", err_str);191	}192 193	return err;194}195 196int open_obj_pinned(const char *path, bool quiet)197{198	char *pname;199	int fd = -1;200 201	pname = strdup(path);202	if (!pname) {203		if (!quiet)204			p_err("mem alloc failed");205		goto out_ret;206	}207 208	fd = bpf_obj_get(pname);209	if (fd < 0) {210		if (!quiet)211			p_err("bpf obj get (%s): %s", pname,212			      errno == EACCES && !is_bpffs(dirname(pname)) ?213			    "directory not in bpf file system (bpffs)" :214			    strerror(errno));215		goto out_free;216	}217 218out_free:219	free(pname);220out_ret:221	return fd;222}223 224int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)225{226	enum bpf_obj_type type;227	int fd;228 229	fd = open_obj_pinned(path, false);230	if (fd < 0)231		return -1;232 233	type = get_fd_type(fd);234	if (type < 0) {235		close(fd);236		return type;237	}238	if (type != exp_type) {239		p_err("incorrect object type: %s", get_fd_type_name(type));240		close(fd);241		return -1;242	}243 244	return fd;245}246 247int create_and_mount_bpffs_dir(const char *dir_name)248{249	char err_str[ERR_MAX_LEN];250	bool dir_exists;251	int err = 0;252 253	if (is_bpffs(dir_name))254		return err;255 256	dir_exists = access(dir_name, F_OK) == 0;257 258	if (!dir_exists) {259		char *temp_name;260		char *parent_name;261 262		temp_name = strdup(dir_name);263		if (!temp_name) {264			p_err("mem alloc failed");265			return -1;266		}267 268		parent_name = dirname(temp_name);269 270		if (is_bpffs(parent_name)) {271			/* nothing to do if already mounted */272			free(temp_name);273			return err;274		}275 276		if (access(parent_name, F_OK) == -1) {277			p_err("can't create dir '%s' to pin BPF object: parent dir '%s' doesn't exist",278			      dir_name, parent_name);279			free(temp_name);280			return -1;281		}282 283		free(temp_name);284	}285 286	if (block_mount) {287		p_err("no BPF file system found, not mounting it due to --nomount option");288		return -1;289	}290 291	if (!dir_exists) {292		err = mkdir(dir_name, S_IRWXU);293		if (err) {294			p_err("failed to create dir '%s': %s", dir_name, strerror(errno));295			return err;296		}297	}298 299	err = mnt_fs(dir_name, "bpf", err_str, ERR_MAX_LEN);300	if (err) {301		err_str[ERR_MAX_LEN - 1] = '\0';302		p_err("can't mount BPF file system on given dir '%s': %s",303		      dir_name, err_str);304 305		if (!dir_exists)306			rmdir(dir_name);307	}308 309	return err;310}311 312int mount_bpffs_for_file(const char *file_name)313{314	char err_str[ERR_MAX_LEN];315	char *temp_name;316	char *dir;317	int err = 0;318 319	if (access(file_name, F_OK) != -1) {320		p_err("can't pin BPF object: path '%s' already exists", file_name);321		return -1;322	}323 324	temp_name = strdup(file_name);325	if (!temp_name) {326		p_err("mem alloc failed");327		return -1;328	}329 330	dir = dirname(temp_name);331 332	if (is_bpffs(dir))333		/* nothing to do if already mounted */334		goto out_free;335 336	if (access(dir, F_OK) == -1) {337		p_err("can't pin BPF object: dir '%s' doesn't exist", dir);338		err = -1;339		goto out_free;340	}341 342	if (block_mount) {343		p_err("no BPF file system found, not mounting it due to --nomount option");344		err = -1;345		goto out_free;346	}347 348	err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);349	if (err) {350		err_str[ERR_MAX_LEN - 1] = '\0';351		p_err("can't mount BPF file system to pin the object '%s': %s",352		      file_name, err_str);353	}354 355out_free:356	free(temp_name);357	return err;358}359 360int do_pin_fd(int fd, const char *name)361{362	int err;363 364	err = mount_bpffs_for_file(name);365	if (err)366		return err;367 368	err = bpf_obj_pin(fd, name);369	if (err)370		p_err("can't pin the object (%s): %s", name, strerror(errno));371 372	return err;373}374 375int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))376{377	int err;378	int fd;379 380	if (!REQ_ARGS(3))381		return -EINVAL;382 383	fd = get_fd(&argc, &argv);384	if (fd < 0)385		return fd;386 387	err = do_pin_fd(fd, *argv);388 389	close(fd);390	return err;391}392 393const char *get_fd_type_name(enum bpf_obj_type type)394{395	static const char * const names[] = {396		[BPF_OBJ_UNKNOWN]	= "unknown",397		[BPF_OBJ_PROG]		= "prog",398		[BPF_OBJ_MAP]		= "map",399		[BPF_OBJ_LINK]		= "link",400	};401 402	if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])403		return names[BPF_OBJ_UNKNOWN];404 405	return names[type];406}407 408void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd,409			char *name_buff, size_t buff_len)410{411	const char *prog_name = prog_info->name;412	const struct btf_type *func_type;413	struct bpf_func_info finfo = {};414	struct bpf_prog_info info = {};415	__u32 info_len = sizeof(info);416	struct btf *prog_btf = NULL;417 418	if (buff_len <= BPF_OBJ_NAME_LEN ||419	    strlen(prog_info->name) < BPF_OBJ_NAME_LEN - 1)420		goto copy_name;421 422	if (!prog_info->btf_id || prog_info->nr_func_info == 0)423		goto copy_name;424 425	info.nr_func_info = 1;426	info.func_info_rec_size = prog_info->func_info_rec_size;427	if (info.func_info_rec_size > sizeof(finfo))428		info.func_info_rec_size = sizeof(finfo);429	info.func_info = ptr_to_u64(&finfo);430 431	if (bpf_prog_get_info_by_fd(prog_fd, &info, &info_len))432		goto copy_name;433 434	prog_btf = btf__load_from_kernel_by_id(info.btf_id);435	if (!prog_btf)436		goto copy_name;437 438	func_type = btf__type_by_id(prog_btf, finfo.type_id);439	if (!func_type || !btf_is_func(func_type))440		goto copy_name;441 442	prog_name = btf__name_by_offset(prog_btf, func_type->name_off);443 444copy_name:445	snprintf(name_buff, buff_len, "%s", prog_name);446 447	if (prog_btf)448		btf__free(prog_btf);449}450 451int get_fd_type(int fd)452{453	char path[PATH_MAX];454	char buf[512];455	ssize_t n;456 457	snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);458 459	n = readlink(path, buf, sizeof(buf));460	if (n < 0) {461		p_err("can't read link type: %s", strerror(errno));462		return -1;463	}464	if (n == sizeof(path)) {465		p_err("can't read link type: path too long!");466		return -1;467	}468 469	if (strstr(buf, "bpf-map"))470		return BPF_OBJ_MAP;471	else if (strstr(buf, "bpf-prog"))472		return BPF_OBJ_PROG;473	else if (strstr(buf, "bpf-link"))474		return BPF_OBJ_LINK;475 476	return BPF_OBJ_UNKNOWN;477}478 479char *get_fdinfo(int fd, const char *key)480{481	char path[PATH_MAX];482	char *line = NULL;483	size_t line_n = 0;484	ssize_t n;485	FILE *fdi;486 487	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);488 489	fdi = fopen(path, "r");490	if (!fdi)491		return NULL;492 493	while ((n = getline(&line, &line_n, fdi)) > 0) {494		char *value;495		int len;496 497		if (!strstr(line, key))498			continue;499 500		fclose(fdi);501 502		value = strchr(line, '\t');503		if (!value || !value[1]) {504			free(line);505			return NULL;506		}507		value++;508 509		len = strlen(value);510		memmove(line, value, len);511		line[len - 1] = '\0';512 513		return line;514	}515 516	free(line);517	fclose(fdi);518	return NULL;519}520 521void print_data_json(uint8_t *data, size_t len)522{523	unsigned int i;524 525	jsonw_start_array(json_wtr);526	for (i = 0; i < len; i++)527		jsonw_printf(json_wtr, "%d", data[i]);528	jsonw_end_array(json_wtr);529}530 531void print_hex_data_json(uint8_t *data, size_t len)532{533	unsigned int i;534 535	jsonw_start_array(json_wtr);536	for (i = 0; i < len; i++)537		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);538	jsonw_end_array(json_wtr);539}540 541/* extra params for nftw cb */542static struct hashmap *build_fn_table;543static enum bpf_obj_type build_fn_type;544 545static int do_build_table_cb(const char *fpath, const struct stat *sb,546			     int typeflag, struct FTW *ftwbuf)547{548	struct bpf_prog_info pinned_info;549	__u32 len = sizeof(pinned_info);550	enum bpf_obj_type objtype;551	int fd, err = 0;552	char *path;553 554	if (typeflag != FTW_F)555		goto out_ret;556 557	fd = open_obj_pinned(fpath, true);558	if (fd < 0)559		goto out_ret;560 561	objtype = get_fd_type(fd);562	if (objtype != build_fn_type)563		goto out_close;564 565	memset(&pinned_info, 0, sizeof(pinned_info));566	if (bpf_prog_get_info_by_fd(fd, &pinned_info, &len))567		goto out_close;568 569	path = strdup(fpath);570	if (!path) {571		err = -1;572		goto out_close;573	}574 575	err = hashmap__append(build_fn_table, pinned_info.id, path);576	if (err) {577		p_err("failed to append entry to hashmap for ID %u, path '%s': %s",578		      pinned_info.id, path, strerror(errno));579		free(path);580		goto out_close;581	}582 583out_close:584	close(fd);585out_ret:586	return err;587}588 589int build_pinned_obj_table(struct hashmap *tab,590			   enum bpf_obj_type type)591{592	struct mntent *mntent = NULL;593	FILE *mntfile = NULL;594	int flags = FTW_PHYS;595	int nopenfd = 16;596	int err = 0;597 598	mntfile = setmntent("/proc/mounts", "r");599	if (!mntfile)600		return -1;601 602	build_fn_table = tab;603	build_fn_type = type;604 605	while ((mntent = getmntent(mntfile))) {606		char *path = mntent->mnt_dir;607 608		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)609			continue;610		err = nftw(path, do_build_table_cb, nopenfd, flags);611		if (err)612			break;613	}614	fclose(mntfile);615	return err;616}617 618void delete_pinned_obj_table(struct hashmap *map)619{620	struct hashmap_entry *entry;621	size_t bkt;622 623	if (!map)624		return;625 626	hashmap__for_each_entry(map, entry, bkt)627		free(entry->pvalue);628 629	hashmap__free(map);630}631 632unsigned int get_page_size(void)633{634	static int result;635 636	if (!result)637		result = getpagesize();638	return result;639}640 641unsigned int get_possible_cpus(void)642{643	int cpus = libbpf_num_possible_cpus();644 645	if (cpus < 0) {646		p_err("Can't get # of possible cpus: %s", strerror(-cpus));647		exit(-1);648	}649	return cpus;650}651 652static char *653ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)654{655	struct stat st;656	int err;657 658	err = stat("/proc/self/ns/net", &st);659	if (err) {660		p_err("Can't stat /proc/self: %s", strerror(errno));661		return NULL;662	}663 664	if (st.st_dev != ns_dev || st.st_ino != ns_ino)665		return NULL;666 667	return if_indextoname(ifindex, buf);668}669 670static int read_sysfs_hex_int(char *path)671{672	char vendor_id_buf[8];673	int len;674	int fd;675 676	fd = open(path, O_RDONLY);677	if (fd < 0) {678		p_err("Can't open %s: %s", path, strerror(errno));679		return -1;680	}681 682	len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));683	close(fd);684	if (len < 0) {685		p_err("Can't read %s: %s", path, strerror(errno));686		return -1;687	}688	if (len >= (int)sizeof(vendor_id_buf)) {689		p_err("Value in %s too long", path);690		return -1;691	}692 693	vendor_id_buf[len] = 0;694 695	return strtol(vendor_id_buf, NULL, 0);696}697 698static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)699{700	char full_path[64];701 702	snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",703		 devname, entry_name);704 705	return read_sysfs_hex_int(full_path);706}707 708const char *709ifindex_to_arch(__u32 ifindex, __u64 ns_dev, __u64 ns_ino, const char **opt)710{711	__maybe_unused int device_id;712	char devname[IF_NAMESIZE];713	int vendor_id;714 715	if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {716		p_err("Can't get net device name for ifindex %d: %s", ifindex,717		      strerror(errno));718		return NULL;719	}720 721	vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");722	if (vendor_id < 0) {723		p_err("Can't get device vendor id for %s", devname);724		return NULL;725	}726 727	switch (vendor_id) {728#ifdef HAVE_LIBBFD_SUPPORT729	case 0x19ee:730		device_id = read_sysfs_netdev_hex_int(devname, "device");731		if (device_id != 0x4000 &&732		    device_id != 0x6000 &&733		    device_id != 0x6003)734			p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");735		*opt = "ctx4";736		return "NFP-6xxx";737#endif /* HAVE_LIBBFD_SUPPORT */738	/* No NFP support in LLVM, we have no valid triple to return. */739	default:740		p_err("Can't get arch name for device vendor id 0x%04x",741		      vendor_id);742		return NULL;743	}744}745 746void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)747{748	char name[IF_NAMESIZE];749 750	if (!ifindex)751		return;752 753	printf("  offloaded_to ");754	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))755		printf("%s", name);756	else757		printf("ifindex %u ns_dev %llu ns_ino %llu",758		       ifindex, ns_dev, ns_inode);759}760 761void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)762{763	char name[IF_NAMESIZE];764 765	if (!ifindex)766		return;767 768	jsonw_name(json_wtr, "dev");769	jsonw_start_object(json_wtr);770	jsonw_uint_field(json_wtr, "ifindex", ifindex);771	jsonw_uint_field(json_wtr, "ns_dev", ns_dev);772	jsonw_uint_field(json_wtr, "ns_inode", ns_inode);773	if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))774		jsonw_string_field(json_wtr, "ifname", name);775	jsonw_end_object(json_wtr);776}777 778int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)779{780	char *endptr;781 782	NEXT_ARGP();783 784	if (*val) {785		p_err("%s already specified", what);786		return -1;787	}788 789	*val = strtoul(**argv, &endptr, 0);790	if (*endptr) {791		p_err("can't parse %s as %s", **argv, what);792		return -1;793	}794	NEXT_ARGP();795 796	return 0;797}798 799int __printf(2, 0)800print_all_levels(__maybe_unused enum libbpf_print_level level,801		 const char *format, va_list args)802{803	return vfprintf(stderr, format, args);804}805 806static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)807{808	char prog_name[MAX_PROG_FULL_NAME];809	unsigned int id = 0;810	int fd, nb_fds = 0;811	void *tmp;812	int err;813 814	while (true) {815		struct bpf_prog_info info = {};816		__u32 len = sizeof(info);817 818		err = bpf_prog_get_next_id(id, &id);819		if (err) {820			if (errno != ENOENT) {821				p_err("%s", strerror(errno));822				goto err_close_fds;823			}824			return nb_fds;825		}826 827		fd = bpf_prog_get_fd_by_id(id);828		if (fd < 0) {829			p_err("can't get prog by id (%u): %s",830			      id, strerror(errno));831			goto err_close_fds;832		}833 834		err = bpf_prog_get_info_by_fd(fd, &info, &len);835		if (err) {836			p_err("can't get prog info (%u): %s",837			      id, strerror(errno));838			goto err_close_fd;839		}840 841		if (tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) {842			close(fd);843			continue;844		}845 846		if (!tag) {847			get_prog_full_name(&info, fd, prog_name,848					   sizeof(prog_name));849			if (strncmp(nametag, prog_name, sizeof(prog_name))) {850				close(fd);851				continue;852			}853		}854 855		if (nb_fds > 0) {856			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));857			if (!tmp) {858				p_err("failed to realloc");859				goto err_close_fd;860			}861			*fds = tmp;862		}863		(*fds)[nb_fds++] = fd;864	}865 866err_close_fd:867	close(fd);868err_close_fds:869	while (--nb_fds >= 0)870		close((*fds)[nb_fds]);871	return -1;872}873 874int prog_parse_fds(int *argc, char ***argv, int **fds)875{876	if (is_prefix(**argv, "id")) {877		unsigned int id;878		char *endptr;879 880		NEXT_ARGP();881 882		id = strtoul(**argv, &endptr, 0);883		if (*endptr) {884			p_err("can't parse %s as ID", **argv);885			return -1;886		}887		NEXT_ARGP();888 889		(*fds)[0] = bpf_prog_get_fd_by_id(id);890		if ((*fds)[0] < 0) {891			p_err("get by id (%u): %s", id, strerror(errno));892			return -1;893		}894		return 1;895	} else if (is_prefix(**argv, "tag")) {896		unsigned char tag[BPF_TAG_SIZE];897 898		NEXT_ARGP();899 900		if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,901			   tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)902		    != BPF_TAG_SIZE) {903			p_err("can't parse tag");904			return -1;905		}906		NEXT_ARGP();907 908		return prog_fd_by_nametag(tag, fds, true);909	} else if (is_prefix(**argv, "name")) {910		char *name;911 912		NEXT_ARGP();913 914		name = **argv;915		if (strlen(name) > MAX_PROG_FULL_NAME - 1) {916			p_err("can't parse name");917			return -1;918		}919		NEXT_ARGP();920 921		return prog_fd_by_nametag(name, fds, false);922	} else if (is_prefix(**argv, "pinned")) {923		char *path;924 925		NEXT_ARGP();926 927		path = **argv;928		NEXT_ARGP();929 930		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);931		if ((*fds)[0] < 0)932			return -1;933		return 1;934	}935 936	p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);937	return -1;938}939 940int prog_parse_fd(int *argc, char ***argv)941{942	int *fds = NULL;943	int nb_fds, fd;944 945	fds = malloc(sizeof(int));946	if (!fds) {947		p_err("mem alloc failed");948		return -1;949	}950	nb_fds = prog_parse_fds(argc, argv, &fds);951	if (nb_fds != 1) {952		if (nb_fds > 1) {953			p_err("several programs match this handle");954			while (nb_fds--)955				close(fds[nb_fds]);956		}957		fd = -1;958		goto exit_free;959	}960 961	fd = fds[0];962exit_free:963	free(fds);964	return fd;965}966 967static int map_fd_by_name(char *name, int **fds)968{969	unsigned int id = 0;970	int fd, nb_fds = 0;971	void *tmp;972	int err;973 974	while (true) {975		struct bpf_map_info info = {};976		__u32 len = sizeof(info);977 978		err = bpf_map_get_next_id(id, &id);979		if (err) {980			if (errno != ENOENT) {981				p_err("%s", strerror(errno));982				goto err_close_fds;983			}984			return nb_fds;985		}986 987		fd = bpf_map_get_fd_by_id(id);988		if (fd < 0) {989			p_err("can't get map by id (%u): %s",990			      id, strerror(errno));991			goto err_close_fds;992		}993 994		err = bpf_map_get_info_by_fd(fd, &info, &len);995		if (err) {996			p_err("can't get map info (%u): %s",997			      id, strerror(errno));998			goto err_close_fd;999		}1000 1001		if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {1002			close(fd);1003			continue;1004		}1005 1006		if (nb_fds > 0) {1007			tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));1008			if (!tmp) {1009				p_err("failed to realloc");1010				goto err_close_fd;1011			}1012			*fds = tmp;1013		}1014		(*fds)[nb_fds++] = fd;1015	}1016 1017err_close_fd:1018	close(fd);1019err_close_fds:1020	while (--nb_fds >= 0)1021		close((*fds)[nb_fds]);1022	return -1;1023}1024 1025int map_parse_fds(int *argc, char ***argv, int **fds)1026{1027	if (is_prefix(**argv, "id")) {1028		unsigned int id;1029		char *endptr;1030 1031		NEXT_ARGP();1032 1033		id = strtoul(**argv, &endptr, 0);1034		if (*endptr) {1035			p_err("can't parse %s as ID", **argv);1036			return -1;1037		}1038		NEXT_ARGP();1039 1040		(*fds)[0] = bpf_map_get_fd_by_id(id);1041		if ((*fds)[0] < 0) {1042			p_err("get map by id (%u): %s", id, strerror(errno));1043			return -1;1044		}1045		return 1;1046	} else if (is_prefix(**argv, "name")) {1047		char *name;1048 1049		NEXT_ARGP();1050 1051		name = **argv;1052		if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {1053			p_err("can't parse name");1054			return -1;1055		}1056		NEXT_ARGP();1057 1058		return map_fd_by_name(name, fds);1059	} else if (is_prefix(**argv, "pinned")) {1060		char *path;1061 1062		NEXT_ARGP();1063 1064		path = **argv;1065		NEXT_ARGP();1066 1067		(*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);1068		if ((*fds)[0] < 0)1069			return -1;1070		return 1;1071	}1072 1073	p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);1074	return -1;1075}1076 1077int map_parse_fd(int *argc, char ***argv)1078{1079	int *fds = NULL;1080	int nb_fds, fd;1081 1082	fds = malloc(sizeof(int));1083	if (!fds) {1084		p_err("mem alloc failed");1085		return -1;1086	}1087	nb_fds = map_parse_fds(argc, argv, &fds);1088	if (nb_fds != 1) {1089		if (nb_fds > 1) {1090			p_err("several maps match this handle");1091			while (nb_fds--)1092				close(fds[nb_fds]);1093		}1094		fd = -1;1095		goto exit_free;1096	}1097 1098	fd = fds[0];1099exit_free:1100	free(fds);1101	return fd;1102}1103 1104int map_parse_fd_and_info(int *argc, char ***argv, struct bpf_map_info *info,1105			  __u32 *info_len)1106{1107	int err;1108	int fd;1109 1110	fd = map_parse_fd(argc, argv);1111	if (fd < 0)1112		return -1;1113 1114	err = bpf_map_get_info_by_fd(fd, info, info_len);1115	if (err) {1116		p_err("can't get map info: %s", strerror(errno));1117		close(fd);1118		return err;1119	}1120 1121	return fd;1122}1123 1124size_t hash_fn_for_key_as_id(long key, void *ctx)1125{1126	return key;1127}1128 1129bool equal_fn_for_key_as_id(long k1, long k2, void *ctx)1130{1131	return k1 == k2;1132}1133 1134const char *bpf_attach_type_input_str(enum bpf_attach_type t)1135{1136	switch (t) {1137	case BPF_CGROUP_INET_INGRESS:		return "ingress";1138	case BPF_CGROUP_INET_EGRESS:		return "egress";1139	case BPF_CGROUP_INET_SOCK_CREATE:	return "sock_create";1140	case BPF_CGROUP_INET_SOCK_RELEASE:	return "sock_release";1141	case BPF_CGROUP_SOCK_OPS:		return "sock_ops";1142	case BPF_CGROUP_DEVICE:			return "device";1143	case BPF_CGROUP_INET4_BIND:		return "bind4";1144	case BPF_CGROUP_INET6_BIND:		return "bind6";1145	case BPF_CGROUP_INET4_CONNECT:		return "connect4";1146	case BPF_CGROUP_INET6_CONNECT:		return "connect6";1147	case BPF_CGROUP_INET4_POST_BIND:	return "post_bind4";1148	case BPF_CGROUP_INET6_POST_BIND:	return "post_bind6";1149	case BPF_CGROUP_INET4_GETPEERNAME:	return "getpeername4";1150	case BPF_CGROUP_INET6_GETPEERNAME:	return "getpeername6";1151	case BPF_CGROUP_INET4_GETSOCKNAME:	return "getsockname4";1152	case BPF_CGROUP_INET6_GETSOCKNAME:	return "getsockname6";1153	case BPF_CGROUP_UDP4_SENDMSG:		return "sendmsg4";1154	case BPF_CGROUP_UDP6_SENDMSG:		return "sendmsg6";1155	case BPF_CGROUP_SYSCTL:			return "sysctl";1156	case BPF_CGROUP_UDP4_RECVMSG:		return "recvmsg4";1157	case BPF_CGROUP_UDP6_RECVMSG:		return "recvmsg6";1158	case BPF_CGROUP_GETSOCKOPT:		return "getsockopt";1159	case BPF_CGROUP_SETSOCKOPT:		return "setsockopt";1160	case BPF_TRACE_RAW_TP:			return "raw_tp";1161	case BPF_TRACE_FENTRY:			return "fentry";1162	case BPF_TRACE_FEXIT:			return "fexit";1163	case BPF_MODIFY_RETURN:			return "mod_ret";1164	case BPF_SK_REUSEPORT_SELECT:		return "sk_skb_reuseport_select";1165	case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:	return "sk_skb_reuseport_select_or_migrate";1166	default:	return libbpf_bpf_attach_type_str(t);1167	}1168}1169 1170int pathname_concat(char *buf, int buf_sz, const char *path,1171		    const char *name)1172{1173	int len;1174 1175	len = snprintf(buf, buf_sz, "%s/%s", path, name);1176	if (len < 0)1177		return -EINVAL;1178	if (len >= buf_sz)1179		return -ENAMETOOLONG;1180 1181	return 0;1182}1183