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 <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_MAGIC
37 #define BPF_FS_MAGIC 0xcafe4a11
38 #endif
39
p_err(const char * fmt,...)40 void 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
p_info(const char * fmt,...)58 void 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
is_bpffs(const char * path)71 static 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) to
82 * memcg-based memory accounting for BPF maps and programs. This was done in
83 * commit 97306be45fbe ("Merge branch 'switch to memcg-based memory
84 * accounting'"), in Linux 5.11.
85 *
86 * Libbpf also offers to probe for memcg-based accounting vs rlimit, but does
87 * so by checking for the availability of a given BPF helper and this has
88 * failed on some kernels with backports in the past, see commit 6b4384ff1088
89 * ("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 to
91 * load a BPF object, and resetting the rlimit. If the load succeeds then
92 * memcg-based accounting is supported.
93 *
94 * This would be too dangerous to do in the library, because multithreaded
95 * applications might attempt to load items while the rlimit is at 0. Given
96 * that bpftool is single-threaded, this is fine to do here.
97 */
known_to_need_rlimit(void)98 static 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 its
119 * current value, because lowering it would be a permanent operation
120 * 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 calls
127 * 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
set_max_rlimit(void)142 void 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
150 static int
mnt_fs(const char * target,const char * type,char * buff,size_t bufflen)151 mnt_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
mount_tracefs(const char * target)182 int 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
open_obj_pinned(const char * path,bool quiet)196 int 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
218 out_free:
219 free(pname);
220 out_ret:
221 return fd;
222 }
223
open_obj_pinned_any(const char * path,enum bpf_obj_type exp_type)224 int 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
create_and_mount_bpffs_dir(const char * dir_name)247 int 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
mount_bpffs_for_file(const char * file_name)312 int 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
355 out_free:
356 free(temp_name);
357 return err;
358 }
359
do_pin_fd(int fd,const char * name)360 int 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
do_pin_any(int argc,char ** argv,int (* get_fd)(int *,char ***))375 int 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
get_fd_type_name(enum bpf_obj_type type)393 const 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
get_prog_full_name(const struct bpf_prog_info * prog_info,int prog_fd,char * name_buff,size_t buff_len)408 void 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
444 copy_name:
445 snprintf(name_buff, buff_len, "%s", prog_name);
446
447 if (prog_btf)
448 btf__free(prog_btf);
449 }
450
get_fd_type(int fd)451 int 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
get_fdinfo(int fd,const char * key)479 char *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
print_data_json(uint8_t * data,size_t len)521 void 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
print_hex_data_json(uint8_t * data,size_t len)531 void 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 */
542 static struct hashmap *build_fn_table;
543 static enum bpf_obj_type build_fn_type;
544
do_build_table_cb(const char * fpath,const struct stat * sb,int typeflag,struct FTW * ftwbuf)545 static 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
583 out_close:
584 close(fd);
585 out_ret:
586 return err;
587 }
588
build_pinned_obj_table(struct hashmap * tab,enum bpf_obj_type type)589 int 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
delete_pinned_obj_table(struct hashmap * map)618 void 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
get_page_size(void)632 unsigned int get_page_size(void)
633 {
634 static int result;
635
636 if (!result)
637 result = getpagesize();
638 return result;
639 }
640
get_possible_cpus(void)641 unsigned 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
652 static char *
ifindex_to_name_ns(__u32 ifindex,__u32 ns_dev,__u32 ns_ino,char * buf)653 ifindex_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
read_sysfs_hex_int(char * path)670 static 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
read_sysfs_netdev_hex_int(char * devname,const char * entry_name)698 static 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
708 const char *
ifindex_to_arch(__u32 ifindex,__u64 ns_dev,__u64 ns_ino,const char ** opt)709 ifindex_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_SUPPORT
729 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
print_dev_plain(__u32 ifindex,__u64 ns_dev,__u64 ns_inode)746 void 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 else
757 printf("ifindex %u ns_dev %llu ns_ino %llu",
758 ifindex, ns_dev, ns_inode);
759 }
760
print_dev_json(__u32 ifindex,__u64 ns_dev,__u64 ns_inode)761 void 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
parse_u32_arg(int * argc,char *** argv,__u32 * val,const char * what)778 int 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
799 int __printf(2, 0)
print_all_levels(__maybe_unused enum libbpf_print_level level,const char * format,va_list args)800 print_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
prog_fd_by_nametag(void * nametag,int ** fds,bool tag)806 static 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
866 err_close_fd:
867 close(fd);
868 err_close_fds:
869 while (--nb_fds >= 0)
870 close((*fds)[nb_fds]);
871 return -1;
872 }
873
prog_parse_fds(int * argc,char *** argv,int ** fds)874 int 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
prog_parse_fd(int * argc,char *** argv)940 int 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];
962 exit_free:
963 free(fds);
964 return fd;
965 }
966
map_fd_by_name(char * name,int ** fds)967 static 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
1017 err_close_fd:
1018 close(fd);
1019 err_close_fds:
1020 while (--nb_fds >= 0)
1021 close((*fds)[nb_fds]);
1022 return -1;
1023 }
1024
map_parse_fds(int * argc,char *** argv,int ** fds)1025 int 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
map_parse_fd(int * argc,char *** argv)1077 int 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];
1099 exit_free:
1100 free(fds);
1101 return fd;
1102 }
1103
map_parse_fd_and_info(int * argc,char *** argv,struct bpf_map_info * info,__u32 * info_len)1104 int 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
hash_fn_for_key_as_id(long key,void * ctx)1124 size_t hash_fn_for_key_as_id(long key, void *ctx)
1125 {
1126 return key;
1127 }
1128
equal_fn_for_key_as_id(long k1,long k2,void * ctx)1129 bool equal_fn_for_key_as_id(long k1, long k2, void *ctx)
1130 {
1131 return k1 == k2;
1132 }
1133
bpf_attach_type_input_str(enum bpf_attach_type t)1134 const 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
pathname_concat(char * buf,int buf_sz,const char * path,const char * name)1170 int 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