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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_SOURCE
5#define _GNU_SOURCE
6#endif
7#include <assert.h>
8#include <ctype.h>
9#include <errno.h>
10#include <fcntl.h>
11#include <ftw.h>
12#include <libgen.h>
13#include <mntent.h>
14#include <stdbool.h>
15#include <stdio.h>
16#include <stdlib.h>
17#include <string.h>
18#include <unistd.h>
19#include <net/if.h>
20#include <sys/mount.h>
21#include <sys/resource.h>
22#include <sys/stat.h>
23#include <sys/vfs.h>
24#include <sys/utsname.h>
25
26#include <linux/filter.h>
27#include <linux/limits.h>
28#include <linux/magic.h>
29#include <linux/unistd.h>
30
31#include <bpf/bpf.h>
32#include <bpf/hashmap.h>
33#include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
34#include <bpf/btf.h>
35#include <zlib.h>
36
37#include "main.h"
38
39#ifndef BPF_FS_MAGIC
40#define BPF_FS_MAGIC 0xcafe4a11
41#endif
42
43void p_err(const char *fmt, ...)
44{
45 va_list ap;
46
47 va_start(ap, fmt);
48 if (json_output) {
49 jsonw_start_object(json_wtr);
50 jsonw_name(json_wtr, "error");
51 jsonw_vprintf_enquote(json_wtr, fmt, ap);
52 jsonw_end_object(json_wtr);
53 } else {
54 fprintf(stderr, "Error: ");
55 vfprintf(stderr, fmt, ap);
56 fprintf(stderr, "\n");
57 }
58 va_end(ap);
59}
60
61void p_info(const char *fmt, ...)
62{
63 va_list ap;
64
65 if (json_output)
66 return;
67
68 va_start(ap, fmt);
69 vfprintf(stderr, fmt, ap);
70 fprintf(stderr, "\n");
71 va_end(ap);
72}
73
74static bool is_bpffs(const char *path)
75{
76 struct statfs st_fs;
77
78 if (statfs(path, &st_fs) < 0)
79 return false;
80
81 return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
82}
83
84/* Probe whether kernel switched from memlock-based (RLIMIT_MEMLOCK) to
85 * memcg-based memory accounting for BPF maps and programs. This was done in
86 * commit 97306be45fbe ("Merge branch 'switch to memcg-based memory
87 * accounting'"), in Linux 5.11.
88 *
89 * Libbpf also offers to probe for memcg-based accounting vs rlimit, but does
90 * so by checking for the availability of a given BPF helper and this has
91 * failed on some kernels with backports in the past, see commit 6b4384ff1088
92 * ("Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"").
93 * Instead, we can probe by lowering the process-based rlimit to 0, trying to
94 * load a BPF object, and resetting the rlimit. If the load succeeds then
95 * memcg-based accounting is supported.
96 *
97 * This would be too dangerous to do in the library, because multithreaded
98 * applications might attempt to load items while the rlimit is at 0. Given
99 * that bpftool is single-threaded, this is fine to do here.
100 */
101static bool known_to_need_rlimit(void)
102{
103 struct rlimit rlim_init, rlim_cur_zero = {};
104 struct bpf_insn insns[] = {
105 BPF_MOV64_IMM(BPF_REG_0, 0),
106 BPF_EXIT_INSN(),
107 };
108 size_t insn_cnt = ARRAY_SIZE(insns);
109 union bpf_attr attr;
110 int prog_fd, err;
111
112 memset(&attr, 0, sizeof(attr));
113 attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
114 attr.insns = ptr_to_u64(insns);
115 attr.insn_cnt = insn_cnt;
116 attr.license = ptr_to_u64("GPL");
117
118 if (getrlimit(RLIMIT_MEMLOCK, &rlim_init))
119 return false;
120
121 /* Drop the soft limit to zero. We maintain the hard limit to its
122 * current value, because lowering it would be a permanent operation
123 * for unprivileged users.
124 */
125 rlim_cur_zero.rlim_max = rlim_init.rlim_max;
126 if (setrlimit(RLIMIT_MEMLOCK, &rlim_cur_zero))
127 return false;
128
129 /* Do not use bpf_prog_load() from libbpf here, because it calls
130 * bump_rlimit_memlock(), interfering with the current probe.
131 */
132 prog_fd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
133 err = errno;
134
135 /* reset soft rlimit to its initial value */
136 setrlimit(RLIMIT_MEMLOCK, &rlim_init);
137
138 if (prog_fd < 0)
139 return err == EPERM;
140
141 close(prog_fd);
142 return false;
143}
144
145void set_max_rlimit(void)
146{
147 struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
148
149 if (known_to_need_rlimit())
150 setrlimit(RLIMIT_MEMLOCK, &rinf);
151}
152
153static int
154mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
155{
156 bool bind_done = false;
157
158 while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
159 if (errno != EINVAL || bind_done) {
160 snprintf(buff, bufflen,
161 "mount --make-private %s failed: %s",
162 target, strerror(errno));
163 return -1;
164 }
165
166 if (mount(target, target, "none", MS_BIND, NULL)) {
167 snprintf(buff, bufflen,
168 "mount --bind %s %s failed: %s",
169 target, target, strerror(errno));
170 return -1;
171 }
172
173 bind_done = true;
174 }
175
176 if (mount(type, target, type, 0, "mode=0700")) {
177 snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
178 type, type, target, strerror(errno));
179 return -1;
180 }
181
182 return 0;
183}
184
185int mount_tracefs(const char *target)
186{
187 char err_str[ERR_MAX_LEN];
188 int err;
189
190 err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
191 if (err) {
192 err_str[ERR_MAX_LEN - 1] = '\0';
193 p_err("can't mount tracefs: %s", err_str);
194 }
195
196 return err;
197}
198
199int open_obj_pinned(const char *path, bool quiet,
200 const struct bpf_obj_get_opts *opts)
201{
202 char *pname;
203 int fd = -1;
204
205 pname = strdup(path);
206 if (!pname) {
207 if (!quiet)
208 p_err("mem alloc failed");
209 goto out_ret;
210 }
211
212 fd = bpf_obj_get_opts(pname, opts);
213 if (fd < 0) {
214 if (!quiet)
215 p_err("bpf obj get (%s): %s", pname,
216 errno == EACCES && !is_bpffs(dirname(pname)) ?
217 "directory not in bpf file system (bpffs)" :
218 strerror(errno));
219 goto out_free;
220 }
221
222out_free:
223 free(pname);
224out_ret:
225 return fd;
226}
227
228int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type,
229 const struct bpf_obj_get_opts *opts)
230{
231 enum bpf_obj_type type;
232 int fd;
233
234 fd = open_obj_pinned(path, false, opts);
235 if (fd < 0)
236 return -1;
237
238 type = get_fd_type(fd);
239 if (type < 0) {
240 close(fd);
241 return type;
242 }
243 if (type != exp_type) {
244 p_err("incorrect object type: %s", get_fd_type_name(type));
245 close(fd);
246 return -1;
247 }
248
249 return fd;
250}
251
252int create_and_mount_bpffs_dir(const char *dir_name)
253{
254 char err_str[ERR_MAX_LEN];
255 bool dir_exists;
256 int err = 0;
257
258 if (is_bpffs(dir_name))
259 return err;
260
261 dir_exists = access(dir_name, F_OK) == 0;
262
263 if (!dir_exists) {
264 char *temp_name;
265 char *parent_name;
266
267 temp_name = strdup(dir_name);
268 if (!temp_name) {
269 p_err("mem alloc failed");
270 return -1;
271 }
272
273 parent_name = dirname(temp_name);
274
275 if (is_bpffs(parent_name)) {
276 /* nothing to do if already mounted */
277 free(temp_name);
278 return err;
279 }
280
281 if (access(parent_name, F_OK) == -1) {
282 p_err("can't create dir '%s' to pin BPF object: parent dir '%s' doesn't exist",
283 dir_name, parent_name);
284 free(temp_name);
285 return -1;
286 }
287
288 free(temp_name);
289 }
290
291 if (block_mount) {
292 p_err("no BPF file system found, not mounting it due to --nomount option");
293 return -1;
294 }
295
296 if (!dir_exists) {
297 err = mkdir(dir_name, S_IRWXU);
298 if (err) {
299 p_err("failed to create dir '%s': %s", dir_name, strerror(errno));
300 return err;
301 }
302 }
303
304 err = mnt_fs(dir_name, "bpf", err_str, ERR_MAX_LEN);
305 if (err) {
306 err_str[ERR_MAX_LEN - 1] = '\0';
307 p_err("can't mount BPF file system on given dir '%s': %s",
308 dir_name, err_str);
309
310 if (!dir_exists)
311 rmdir(dir_name);
312 }
313
314 return err;
315}
316
317int mount_bpffs_for_file(const char *file_name)
318{
319 char err_str[ERR_MAX_LEN];
320 char *temp_name;
321 char *dir;
322 int err = 0;
323
324 if (access(file_name, F_OK) != -1) {
325 p_err("can't pin BPF object: path '%s' already exists", file_name);
326 return -1;
327 }
328
329 temp_name = strdup(file_name);
330 if (!temp_name) {
331 p_err("mem alloc failed");
332 return -1;
333 }
334
335 dir = dirname(temp_name);
336
337 if (is_bpffs(dir))
338 /* nothing to do if already mounted */
339 goto out_free;
340
341 if (access(dir, F_OK) == -1) {
342 p_err("can't pin BPF object: dir '%s' doesn't exist", dir);
343 err = -1;
344 goto out_free;
345 }
346
347 if (block_mount) {
348 p_err("no BPF file system found, not mounting it due to --nomount option");
349 err = -1;
350 goto out_free;
351 }
352
353 err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
354 if (err) {
355 err_str[ERR_MAX_LEN - 1] = '\0';
356 p_err("can't mount BPF file system to pin the object '%s': %s",
357 file_name, err_str);
358 }
359
360out_free:
361 free(temp_name);
362 return err;
363}
364
365int do_pin_fd(int fd, const char *name)
366{
367 int err;
368
369 err = mount_bpffs_for_file(name);
370 if (err)
371 return err;
372
373 err = bpf_obj_pin(fd, name);
374 if (err)
375 p_err("can't pin the object (%s): %s", name, strerror(errno));
376
377 return err;
378}
379
380int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
381{
382 int err;
383 int fd;
384
385 if (!REQ_ARGS(3))
386 return -EINVAL;
387
388 fd = get_fd(&argc, &argv);
389 if (fd < 0)
390 return fd;
391
392 err = do_pin_fd(fd, *argv);
393
394 close(fd);
395 return err;
396}
397
398const char *get_fd_type_name(enum bpf_obj_type type)
399{
400 static const char * const names[] = {
401 [BPF_OBJ_UNKNOWN] = "unknown",
402 [BPF_OBJ_PROG] = "prog",
403 [BPF_OBJ_MAP] = "map",
404 [BPF_OBJ_LINK] = "link",
405 };
406
407 if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
408 return names[BPF_OBJ_UNKNOWN];
409
410 return names[type];
411}
412
413void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd,
414 char *name_buff, size_t buff_len)
415{
416 const char *prog_name = prog_info->name;
417 const struct btf_type *func_type;
418 struct bpf_func_info finfo = {};
419 struct bpf_prog_info info = {};
420 __u32 info_len = sizeof(info);
421 struct btf *prog_btf = NULL;
422
423 if (buff_len <= BPF_OBJ_NAME_LEN ||
424 strlen(prog_info->name) < BPF_OBJ_NAME_LEN - 1)
425 goto copy_name;
426
427 if (!prog_info->btf_id || prog_info->nr_func_info == 0)
428 goto copy_name;
429
430 info.nr_func_info = 1;
431 info.func_info_rec_size = prog_info->func_info_rec_size;
432 if (info.func_info_rec_size > sizeof(finfo))
433 info.func_info_rec_size = sizeof(finfo);
434 info.func_info = ptr_to_u64(&finfo);
435
436 if (bpf_prog_get_info_by_fd(prog_fd, &info, &info_len))
437 goto copy_name;
438
439 prog_btf = btf__load_from_kernel_by_id(info.btf_id);
440 if (!prog_btf)
441 goto copy_name;
442
443 func_type = btf__type_by_id(prog_btf, finfo.type_id);
444 if (!func_type || !btf_is_func(func_type))
445 goto copy_name;
446
447 prog_name = btf__name_by_offset(prog_btf, func_type->name_off);
448
449copy_name:
450 snprintf(name_buff, buff_len, "%s", prog_name);
451
452 if (prog_btf)
453 btf__free(prog_btf);
454}
455
456int get_fd_type(int fd)
457{
458 char path[PATH_MAX];
459 char buf[512];
460 ssize_t n;
461
462 snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
463
464 n = readlink(path, buf, sizeof(buf));
465 if (n < 0) {
466 p_err("can't read link type: %s", strerror(errno));
467 return -1;
468 }
469 if (n == sizeof(buf)) {
470 p_err("can't read link type: path too long!");
471 return -1;
472 }
473 buf[n] = '\0';
474
475 if (strstr(buf, "bpf-map"))
476 return BPF_OBJ_MAP;
477 else if (strstr(buf, "bpf-prog"))
478 return BPF_OBJ_PROG;
479 else if (strstr(buf, "bpf-link"))
480 return BPF_OBJ_LINK;
481
482 return BPF_OBJ_UNKNOWN;
483}
484
485char *get_fdinfo(int fd, const char *key)
486{
487 char path[PATH_MAX];
488 char *line = NULL;
489 size_t line_n = 0;
490 ssize_t n;
491 FILE *fdi;
492
493 snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
494
495 fdi = fopen(path, "r");
496 if (!fdi)
497 return NULL;
498
499 while ((n = getline(&line, &line_n, fdi)) > 0) {
500 char *value;
501 int len;
502
503 if (!strstr(line, key))
504 continue;
505
506 fclose(fdi);
507
508 value = strchr(line, '\t');
509 if (!value || !value[1]) {
510 free(line);
511 return NULL;
512 }
513 value++;
514
515 len = strlen(value);
516 memmove(line, value, len);
517 line[len - 1] = '\0';
518
519 return line;
520 }
521
522 free(line);
523 fclose(fdi);
524 return NULL;
525}
526
527void print_data_json(uint8_t *data, size_t len)
528{
529 unsigned int i;
530
531 jsonw_start_array(json_wtr);
532 for (i = 0; i < len; i++)
533 jsonw_printf(json_wtr, "%d", data[i]);
534 jsonw_end_array(json_wtr);
535}
536
537void print_hex_data_json(uint8_t *data, size_t len)
538{
539 unsigned int i;
540
541 jsonw_start_array(json_wtr);
542 for (i = 0; i < len; i++)
543 jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
544 jsonw_end_array(json_wtr);
545}
546
547/* extra params for nftw cb */
548static struct hashmap *build_fn_table;
549static enum bpf_obj_type build_fn_type;
550
551static int do_build_table_cb(const char *fpath, const struct stat *sb,
552 int typeflag, struct FTW *ftwbuf)
553{
554 struct bpf_prog_info pinned_info;
555 __u32 len = sizeof(pinned_info);
556 enum bpf_obj_type objtype;
557 int fd, err = 0;
558 char *path;
559
560 if (typeflag != FTW_F)
561 goto out_ret;
562
563 fd = open_obj_pinned(fpath, true, NULL);
564 if (fd < 0)
565 goto out_ret;
566
567 objtype = get_fd_type(fd);
568 if (objtype != build_fn_type)
569 goto out_close;
570
571 memset(&pinned_info, 0, sizeof(pinned_info));
572 if (bpf_prog_get_info_by_fd(fd, &pinned_info, &len))
573 goto out_close;
574
575 path = strdup(fpath);
576 if (!path) {
577 err = -1;
578 goto out_close;
579 }
580
581 err = hashmap__append(build_fn_table, pinned_info.id, path);
582 if (err) {
583 p_err("failed to append entry to hashmap for ID %u, path '%s': %s",
584 pinned_info.id, path, strerror(errno));
585 free(path);
586 goto out_close;
587 }
588
589out_close:
590 close(fd);
591out_ret:
592 return err;
593}
594
595int build_pinned_obj_table(struct hashmap *tab,
596 enum bpf_obj_type type)
597{
598 struct mntent *mntent = NULL;
599 FILE *mntfile = NULL;
600 int flags = FTW_PHYS;
601 int nopenfd = 16;
602 int err = 0;
603
604 mntfile = setmntent("/proc/mounts", "r");
605 if (!mntfile)
606 return -1;
607
608 build_fn_table = tab;
609 build_fn_type = type;
610
611 while ((mntent = getmntent(mntfile))) {
612 char *path = mntent->mnt_dir;
613
614 if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
615 continue;
616 err = nftw(path, do_build_table_cb, nopenfd, flags);
617 if (err)
618 break;
619 }
620 fclose(mntfile);
621 return err;
622}
623
624void delete_pinned_obj_table(struct hashmap *map)
625{
626 struct hashmap_entry *entry;
627 size_t bkt;
628
629 if (!map)
630 return;
631
632 hashmap__for_each_entry(map, entry, bkt)
633 free(entry->pvalue);
634
635 hashmap__free(map);
636}
637
638unsigned int get_page_size(void)
639{
640 static int result;
641
642 if (!result)
643 result = getpagesize();
644 return result;
645}
646
647unsigned int get_possible_cpus(void)
648{
649 int cpus = libbpf_num_possible_cpus();
650
651 if (cpus < 0) {
652 p_err("Can't get # of possible cpus: %s", strerror(-cpus));
653 exit(-1);
654 }
655 return cpus;
656}
657
658static char *
659ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
660{
661 struct stat st;
662 int err;
663
664 err = stat("/proc/self/ns/net", &st);
665 if (err) {
666 p_err("Can't stat /proc/self: %s", strerror(errno));
667 return NULL;
668 }
669
670 if (st.st_dev != ns_dev || st.st_ino != ns_ino)
671 return NULL;
672
673 return if_indextoname(ifindex, buf);
674}
675
676static int read_sysfs_hex_int(char *path)
677{
678 char vendor_id_buf[8];
679 int len;
680 int fd;
681
682 fd = open(path, O_RDONLY);
683 if (fd < 0) {
684 p_err("Can't open %s: %s", path, strerror(errno));
685 return -1;
686 }
687
688 len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
689 close(fd);
690 if (len < 0) {
691 p_err("Can't read %s: %s", path, strerror(errno));
692 return -1;
693 }
694 if (len >= (int)sizeof(vendor_id_buf)) {
695 p_err("Value in %s too long", path);
696 return -1;
697 }
698
699 vendor_id_buf[len] = 0;
700
701 return strtol(vendor_id_buf, NULL, 0);
702}
703
704static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
705{
706 char full_path[64];
707
708 snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
709 devname, entry_name);
710
711 return read_sysfs_hex_int(full_path);
712}
713
714const char *
715ifindex_to_arch(__u32 ifindex, __u64 ns_dev, __u64 ns_ino, const char **opt)
716{
717 __maybe_unused int device_id;
718 char devname[IF_NAMESIZE];
719 int vendor_id;
720
721 if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
722 p_err("Can't get net device name for ifindex %u: %s", ifindex,
723 strerror(errno));
724 return NULL;
725 }
726
727 vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
728 if (vendor_id < 0) {
729 p_err("Can't get device vendor id for %s", devname);
730 return NULL;
731 }
732
733 switch (vendor_id) {
734#ifdef HAVE_LIBBFD_SUPPORT
735 case 0x19ee:
736 device_id = read_sysfs_netdev_hex_int(devname, "device");
737 if (device_id != 0x4000 &&
738 device_id != 0x6000 &&
739 device_id != 0x6003)
740 p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
741 *opt = "ctx4";
742 return "NFP-6xxx";
743#endif /* HAVE_LIBBFD_SUPPORT */
744 /* No NFP support in LLVM, we have no valid triple to return. */
745 default:
746 p_err("Can't get arch name for device vendor id 0x%04x",
747 (unsigned int)vendor_id);
748 return NULL;
749 }
750}
751
752void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
753{
754 char name[IF_NAMESIZE];
755
756 if (!ifindex)
757 return;
758
759 printf(" offloaded_to ");
760 if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
761 printf("%s", name);
762 else
763 printf("ifindex %u ns_dev %llu ns_ino %llu",
764 ifindex, ns_dev, ns_inode);
765}
766
767void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
768{
769 char name[IF_NAMESIZE];
770
771 if (!ifindex)
772 return;
773
774 jsonw_name(json_wtr, "dev");
775 jsonw_start_object(json_wtr);
776 jsonw_uint_field(json_wtr, "ifindex", ifindex);
777 jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
778 jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
779 if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
780 jsonw_string_field(json_wtr, "ifname", name);
781 jsonw_end_object(json_wtr);
782}
783
784int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
785{
786 char *endptr;
787
788 NEXT_ARGP();
789
790 if (*val) {
791 p_err("%s already specified", what);
792 return -1;
793 }
794
795 *val = strtoul(**argv, &endptr, 0);
796 if (*endptr) {
797 p_err("can't parse %s as %s", **argv, what);
798 return -1;
799 }
800 NEXT_ARGP();
801
802 return 0;
803}
804
805int __printf(2, 0)
806print_all_levels(__maybe_unused enum libbpf_print_level level,
807 const char *format, va_list args)
808{
809 return vfprintf(stderr, format, args);
810}
811
812static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
813{
814 char prog_name[MAX_PROG_FULL_NAME];
815 unsigned int id = 0;
816 int fd, nb_fds = 0;
817 void *tmp;
818 int err;
819
820 while (true) {
821 struct bpf_prog_info info = {};
822 __u32 len = sizeof(info);
823
824 err = bpf_prog_get_next_id(id, &id);
825 if (err) {
826 if (errno != ENOENT) {
827 p_err("%s", strerror(errno));
828 goto err_close_fds;
829 }
830 return nb_fds;
831 }
832
833 fd = bpf_prog_get_fd_by_id(id);
834 if (fd < 0) {
835 if (errno == ENOENT)
836 continue;
837 p_err("can't get prog by id (%u): %s",
838 id, strerror(errno));
839 goto err_close_fds;
840 }
841
842 err = bpf_prog_get_info_by_fd(fd, &info, &len);
843 if (err) {
844 p_err("can't get prog info (%u): %s",
845 id, strerror(errno));
846 goto err_close_fd;
847 }
848
849 if (tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) {
850 close(fd);
851 continue;
852 }
853
854 if (!tag) {
855 get_prog_full_name(&info, fd, prog_name,
856 sizeof(prog_name));
857 if (strncmp(nametag, prog_name, sizeof(prog_name))) {
858 close(fd);
859 continue;
860 }
861 }
862
863 if (nb_fds > 0) {
864 tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
865 if (!tmp) {
866 p_err("failed to realloc");
867 goto err_close_fd;
868 }
869 *fds = tmp;
870 }
871 (*fds)[nb_fds++] = fd;
872 }
873
874err_close_fd:
875 close(fd);
876err_close_fds:
877 while (--nb_fds >= 0)
878 close((*fds)[nb_fds]);
879 return -1;
880}
881
882int prog_parse_fds(int *argc, char ***argv, int **fds)
883{
884 if (is_prefix(**argv, "id")) {
885 unsigned int id;
886 char *endptr;
887
888 NEXT_ARGP();
889
890 id = strtoul(**argv, &endptr, 0);
891 if (*endptr) {
892 p_err("can't parse %s as ID", **argv);
893 return -1;
894 }
895 NEXT_ARGP();
896
897 (*fds)[0] = bpf_prog_get_fd_by_id(id);
898 if ((*fds)[0] < 0) {
899 p_err("get by id (%u): %s", id, strerror(errno));
900 return -1;
901 }
902 return 1;
903 } else if (is_prefix(**argv, "tag")) {
904 unsigned char tag[BPF_TAG_SIZE];
905
906 NEXT_ARGP();
907
908 if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
909 tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
910 != BPF_TAG_SIZE) {
911 p_err("can't parse tag");
912 return -1;
913 }
914 NEXT_ARGP();
915
916 return prog_fd_by_nametag(tag, fds, true);
917 } else if (is_prefix(**argv, "name")) {
918 char *name;
919
920 NEXT_ARGP();
921
922 name = **argv;
923 if (strlen(name) > MAX_PROG_FULL_NAME - 1) {
924 p_err("can't parse name");
925 return -1;
926 }
927 NEXT_ARGP();
928
929 return prog_fd_by_nametag(name, fds, false);
930 } else if (is_prefix(**argv, "pinned")) {
931 char *path;
932
933 NEXT_ARGP();
934
935 path = **argv;
936 NEXT_ARGP();
937
938 (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG, NULL);
939 if ((*fds)[0] < 0)
940 return -1;
941 return 1;
942 }
943
944 p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
945 return -1;
946}
947
948int prog_parse_fd(int *argc, char ***argv)
949{
950 int *fds = NULL;
951 int nb_fds, fd;
952
953 fds = malloc(sizeof(int));
954 if (!fds) {
955 p_err("mem alloc failed");
956 return -1;
957 }
958 nb_fds = prog_parse_fds(argc, argv, &fds);
959 if (nb_fds != 1) {
960 if (nb_fds > 1) {
961 p_err("several programs match this handle");
962 while (nb_fds--)
963 close(fds[nb_fds]);
964 }
965 fd = -1;
966 goto exit_free;
967 }
968
969 fd = fds[0];
970exit_free:
971 free(fds);
972 return fd;
973}
974
975static int map_fd_by_name(char *name, int **fds,
976 const struct bpf_get_fd_by_id_opts *opts)
977{
978 unsigned int id = 0;
979 int fd, nb_fds = 0;
980 void *tmp;
981 int err;
982
983 while (true) {
984 LIBBPF_OPTS(bpf_get_fd_by_id_opts, opts_ro);
985 struct bpf_map_info info = {};
986 __u32 len = sizeof(info);
987
988 err = bpf_map_get_next_id(id, &id);
989 if (err) {
990 if (errno != ENOENT) {
991 p_err("%s", strerror(errno));
992 goto err_close_fds;
993 }
994 return nb_fds;
995 }
996
997 /* Request a read-only fd to query the map info */
998 opts_ro.open_flags = BPF_F_RDONLY;
999 fd = bpf_map_get_fd_by_id_opts(id, &opts_ro);
1000 if (fd < 0) {
1001 if (errno == ENOENT)
1002 continue;
1003 p_err("can't get map by id (%u): %s",
1004 id, strerror(errno));
1005 goto err_close_fds;
1006 }
1007
1008 err = bpf_map_get_info_by_fd(fd, &info, &len);
1009 if (err) {
1010 p_err("can't get map info (%u): %s",
1011 id, strerror(errno));
1012 goto err_close_fd;
1013 }
1014
1015 if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
1016 close(fd);
1017 continue;
1018 }
1019
1020 /* Get an fd with the requested options, if they differ
1021 * from the read-only options used to get the fd above.
1022 */
1023 if (memcmp(opts, &opts_ro, sizeof(opts_ro))) {
1024 close(fd);
1025 fd = bpf_map_get_fd_by_id_opts(id, opts);
1026 if (fd < 0) {
1027 p_err("can't get map by id (%u): %s", id,
1028 strerror(errno));
1029 goto err_close_fds;
1030 }
1031 }
1032
1033 if (nb_fds > 0) {
1034 tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
1035 if (!tmp) {
1036 p_err("failed to realloc");
1037 goto err_close_fd;
1038 }
1039 *fds = tmp;
1040 }
1041 (*fds)[nb_fds++] = fd;
1042 }
1043
1044err_close_fd:
1045 close(fd);
1046err_close_fds:
1047 while (--nb_fds >= 0)
1048 close((*fds)[nb_fds]);
1049 return -1;
1050}
1051
1052int map_parse_fds(int *argc, char ***argv, int **fds, __u32 open_flags)
1053{
1054 LIBBPF_OPTS(bpf_get_fd_by_id_opts, opts);
1055
1056 assert((open_flags & ~BPF_F_RDONLY) == 0);
1057 opts.open_flags = open_flags;
1058
1059 if (is_prefix(**argv, "id")) {
1060 unsigned int id;
1061 char *endptr;
1062
1063 NEXT_ARGP();
1064
1065 id = strtoul(**argv, &endptr, 0);
1066 if (*endptr) {
1067 p_err("can't parse %s as ID", **argv);
1068 return -1;
1069 }
1070 NEXT_ARGP();
1071
1072 (*fds)[0] = bpf_map_get_fd_by_id_opts(id, &opts);
1073 if ((*fds)[0] < 0) {
1074 p_err("get map by id (%u): %s", id, strerror(errno));
1075 return -1;
1076 }
1077 return 1;
1078 } else if (is_prefix(**argv, "name")) {
1079 char *name;
1080
1081 NEXT_ARGP();
1082
1083 name = **argv;
1084 if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
1085 p_err("can't parse name");
1086 return -1;
1087 }
1088 NEXT_ARGP();
1089
1090 return map_fd_by_name(name, fds, &opts);
1091 } else if (is_prefix(**argv, "pinned")) {
1092 char *path;
1093 LIBBPF_OPTS(bpf_obj_get_opts, get_opts);
1094 get_opts.file_flags = open_flags;
1095
1096 NEXT_ARGP();
1097
1098 path = **argv;
1099 NEXT_ARGP();
1100
1101 (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP, &get_opts);
1102 if ((*fds)[0] < 0)
1103 return -1;
1104 return 1;
1105 }
1106
1107 p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
1108 return -1;
1109}
1110
1111int map_parse_fd(int *argc, char ***argv, __u32 open_flags)
1112{
1113 int *fds = NULL;
1114 int nb_fds, fd;
1115
1116 fds = malloc(sizeof(int));
1117 if (!fds) {
1118 p_err("mem alloc failed");
1119 return -1;
1120 }
1121 nb_fds = map_parse_fds(argc, argv, &fds, open_flags);
1122 if (nb_fds != 1) {
1123 if (nb_fds > 1) {
1124 p_err("several maps match this handle");
1125 while (nb_fds--)
1126 close(fds[nb_fds]);
1127 }
1128 fd = -1;
1129 goto exit_free;
1130 }
1131
1132 fd = fds[0];
1133exit_free:
1134 free(fds);
1135 return fd;
1136}
1137
1138int map_parse_fd_and_info(int *argc, char ***argv, struct bpf_map_info *info,
1139 __u32 *info_len, __u32 open_flags)
1140{
1141 int err;
1142 int fd;
1143
1144 fd = map_parse_fd(argc, argv, open_flags);
1145 if (fd < 0)
1146 return -1;
1147
1148 err = bpf_map_get_info_by_fd(fd, info, info_len);
1149 if (err) {
1150 p_err("can't get map info: %s", strerror(errno));
1151 close(fd);
1152 return err;
1153 }
1154
1155 return fd;
1156}
1157
1158size_t hash_fn_for_key_as_id(long key, void *ctx)
1159{
1160 return key;
1161}
1162
1163bool equal_fn_for_key_as_id(long k1, long k2, void *ctx)
1164{
1165 return k1 == k2;
1166}
1167
1168const char *bpf_attach_type_input_str(enum bpf_attach_type t)
1169{
1170 switch (t) {
1171 case BPF_CGROUP_INET_INGRESS: return "ingress";
1172 case BPF_CGROUP_INET_EGRESS: return "egress";
1173 case BPF_CGROUP_INET_SOCK_CREATE: return "sock_create";
1174 case BPF_CGROUP_INET_SOCK_RELEASE: return "sock_release";
1175 case BPF_CGROUP_SOCK_OPS: return "sock_ops";
1176 case BPF_CGROUP_DEVICE: return "device";
1177 case BPF_CGROUP_INET4_BIND: return "bind4";
1178 case BPF_CGROUP_INET6_BIND: return "bind6";
1179 case BPF_CGROUP_INET4_CONNECT: return "connect4";
1180 case BPF_CGROUP_INET6_CONNECT: return "connect6";
1181 case BPF_CGROUP_INET4_POST_BIND: return "post_bind4";
1182 case BPF_CGROUP_INET6_POST_BIND: return "post_bind6";
1183 case BPF_CGROUP_INET4_GETPEERNAME: return "getpeername4";
1184 case BPF_CGROUP_INET6_GETPEERNAME: return "getpeername6";
1185 case BPF_CGROUP_INET4_GETSOCKNAME: return "getsockname4";
1186 case BPF_CGROUP_INET6_GETSOCKNAME: return "getsockname6";
1187 case BPF_CGROUP_UDP4_SENDMSG: return "sendmsg4";
1188 case BPF_CGROUP_UDP6_SENDMSG: return "sendmsg6";
1189 case BPF_CGROUP_SYSCTL: return "sysctl";
1190 case BPF_CGROUP_UDP4_RECVMSG: return "recvmsg4";
1191 case BPF_CGROUP_UDP6_RECVMSG: return "recvmsg6";
1192 case BPF_CGROUP_GETSOCKOPT: return "getsockopt";
1193 case BPF_CGROUP_SETSOCKOPT: return "setsockopt";
1194 case BPF_TRACE_RAW_TP: return "raw_tp";
1195 case BPF_TRACE_FENTRY: return "fentry";
1196 case BPF_TRACE_FEXIT: return "fexit";
1197 case BPF_MODIFY_RETURN: return "mod_ret";
1198 case BPF_TRACE_FSESSION: return "fsession";
1199 case BPF_SK_REUSEPORT_SELECT: return "sk_skb_reuseport_select";
1200 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: return "sk_skb_reuseport_select_or_migrate";
1201 default: return libbpf_bpf_attach_type_str(t);
1202 }
1203}
1204
1205int pathname_concat(char *buf, int buf_sz, const char *path,
1206 const char *name)
1207{
1208 int len;
1209
1210 len = snprintf(buf, buf_sz, "%s/%s", path, name);
1211 if (len < 0)
1212 return -EINVAL;
1213 if (len >= buf_sz)
1214 return -ENAMETOOLONG;
1215
1216 return 0;
1217}
1218
1219static bool read_next_kernel_config_option(gzFile file, char *buf, size_t n,
1220 char **value)
1221{
1222 char *sep;
1223
1224 while (gzgets(file, buf, n)) {
1225 if (strncmp(buf, "CONFIG_", 7))
1226 continue;
1227
1228 sep = strchr(buf, '=');
1229 if (!sep)
1230 continue;
1231
1232 /* Trim ending '\n' */
1233 buf[strlen(buf) - 1] = '\0';
1234
1235 /* Split on '=' and ensure that a value is present. */
1236 *sep = '\0';
1237 if (!sep[1])
1238 continue;
1239
1240 *value = sep + 1;
1241 return true;
1242 }
1243
1244 return false;
1245}
1246
1247int read_kernel_config(const struct kernel_config_option *requested_options,
1248 size_t num_options, char **out_values,
1249 const char *define_prefix)
1250{
1251 struct utsname utsn;
1252 char path[PATH_MAX];
1253 gzFile file = NULL;
1254 char buf[4096];
1255 char *value;
1256 size_t i;
1257 int ret = 0;
1258
1259 if (!requested_options || !out_values || num_options == 0)
1260 return -1;
1261
1262 if (!uname(&utsn)) {
1263 snprintf(path, sizeof(path), "/boot/config-%s", utsn.release);
1264
1265 /* gzopen also accepts uncompressed files. */
1266 file = gzopen(path, "r");
1267 }
1268
1269 if (!file) {
1270 /* Some distributions build with CONFIG_IKCONFIG=y and put the
1271 * config file at /proc/config.gz.
1272 */
1273 file = gzopen("/proc/config.gz", "r");
1274 }
1275
1276 if (!file) {
1277 p_info("skipping kernel config, can't open file: %s",
1278 strerror(errno));
1279 return -1;
1280 }
1281
1282 if (!gzgets(file, buf, sizeof(buf)) || !gzgets(file, buf, sizeof(buf))) {
1283 p_info("skipping kernel config, can't read from file: %s",
1284 strerror(errno));
1285 ret = -1;
1286 goto end_parse;
1287 }
1288
1289 if (strcmp(buf, "# Automatically generated file; DO NOT EDIT.\n")) {
1290 p_info("skipping kernel config, can't find correct file");
1291 ret = -1;
1292 goto end_parse;
1293 }
1294
1295 while (read_next_kernel_config_option(file, buf, sizeof(buf), &value)) {
1296 for (i = 0; i < num_options; i++) {
1297 if ((define_prefix && !requested_options[i].macro_dump) ||
1298 out_values[i] || strcmp(buf, requested_options[i].name))
1299 continue;
1300
1301 out_values[i] = strdup(value);
1302 }
1303 }
1304
1305end_parse:
1306 gzclose(file);
1307 return ret;
1308}